This review focuses on major contemporary empirical studies that examine both the physical and regulatory sides of climate risk. These studies explore how climate risk affects firms’ operating performance and leverag...This review focuses on major contemporary empirical studies that examine both the physical and regulatory sides of climate risk. These studies explore how climate risk affects firms’ operating performance and leverage, stock and bond valuation, cost of capital, and managerial behavior. We also discuss how the effect of climate risk on real estate markets depends on individuals’ beliefs about climate change. Furthermore, we summarize papers on climate risk activism and how firms can employ financial devices and technology to mitigate their climate risk. Finally, we make some recommendations for further research areas.展开更多
We classify all positive solutions for the following integral system:{ui(x)=∫Rn1/│x-y│^n-α fi(u(y))dy,x∈R^n,i=1,…,m,0〈α〈n,and u(x)=(u1(x),u2(x)…,um(x)).Here fi(u), 1 ≤ i ≤m, monotone non...We classify all positive solutions for the following integral system:{ui(x)=∫Rn1/│x-y│^n-α fi(u(y))dy,x∈R^n,i=1,…,m,0〈α〈n,and u(x)=(u1(x),u2(x)…,um(x)).Here fi(u), 1 ≤ i ≤m, monotone nondecreasing are real-valued functions of homogeneous degree n+α/n-α and are monotone nondecreasing with respect to all the independent variables U1, u2, ..., urn.In the special case n ≥ 3 and α = 2. we show that the above system is equivalent to thefollowing elliptic PDE system:This system is closely related to the stationary SchrSdinger system with critical exponents for Bose-Einstein condensate展开更多
Degenerative disease of the lumbar spine is a common and increasingly prevalent condition that is often implicated as the primary reason for chronic low back pain and the leading cause of disability in the western wor...Degenerative disease of the lumbar spine is a common and increasingly prevalent condition that is often implicated as the primary reason for chronic low back pain and the leading cause of disability in the western world. Surgical management of lumbar degenerative disease has historically been approached by way of open surgical procedures aimed at decompressing and/or stabilizing the lumbar spine. Advances in technology andsurgical instrumentation have led to minimally invasive surgical techniques being developed and increasingly used in the treatment of lumbar degenerative disease. Compared to the traditional open spine surgery, minimally invasive techniques require smaller incisions and decrease approach-related morbidity by avoiding muscle crush injury by self-retaining retractors, preventing the disruption of tendon attachment sites of important muscles at the spinous processes, using known anatomic neurovascular and muscle planes, and minimizing collateral soft-tissue injury by limiting the width of the surgical corridor. The theoretical benefits of minimally invasive surgery over traditional open surgery include reduced blood loss, decreased postoperative pain and narcotics use, shorter hospital length of stay, faster recover and quicker return to work and normal activity. This paper describes the different minimally invasive techniques that are currently available for the treatment of degenerative disease of the lumbar spine.展开更多
Ejaculatory dysfunction is a highly prevalent clinical condition that may be classified along a continuum that ranges from premature ejaculation (PE), through retarded or delayed ejaculation (DE), to complete anej...Ejaculatory dysfunction is a highly prevalent clinical condition that may be classified along a continuum that ranges from premature ejaculation (PE), through retarded or delayed ejaculation (DE), to complete anejaculation (AE). Retrograde ejaculation (RE) represents a distinct entity in which ejaculate is expelled either partially or completely into the bladder. While DE and PE are significant sources of sexual dissatisfaction among men and their partners, patients with these disorders retain normal fertility in most cases. Conversely, men with AE and RE are unable to deliver sperm into the female genital tract and are therefore rendered subfertile. Therefore, in reviewing ejaculatory disorders as they relate to fertility, this paper will primarily focus on the diagnosis and management of AE and RE. Physiology, diagnostic strategies, pharmacological treatments, and procedural interventions relevant to AE and RE are discussed.展开更多
AIM:To evaluate if human immunodeficiency virus (HIV) population is getting adequate screening for colon cancer in the highly active anti-retroviral treatment (HAART) era with improved longevity, and the prevalence of...AIM:To evaluate if human immunodeficiency virus (HIV) population is getting adequate screening for colon cancer in the highly active anti-retroviral treatment (HAART) era with improved longevity, and the prevalence of polyps and adenomas in this population, when compared with the general population. METHODS:We conducted retrospective chart review of average-risk HIV population for colon cancer attending our infectious disease clinic. Individuals who underwent diagnostic colonoscopy were excluded. We extracted various demographic, HIV disease-specific and colonoscopy data including histo-pathological reports in the last 10 years. Total population was divided into a study group, who underwent screening colonoscopy and a control group who did not. We analyzed data using standard statistical methods and software. RESULTS:We found that 25% of average-risk HIVinfected population was screened for colon cancer using colonoscopy. There was no difference in gender and ethnic distribution between the groups. We foundwider distribution of age (50-84 years with mean 56 years) in the control group when compared to (50-73 years with mean 58 years) the study group. However, there were 89% of subjects with well-controlled HIV disease measured by HIV RNA copies of < 75 in the study group when compared with 70% in the control group (P < 0.0001). We noticed polyp detection rate of 55% and adenoma detection rate of 32% in HIV population. CONCLUSION:It is unclear whether HIV or HAART medications play a role in increased prevalence of adenomas. We suggest that when estimating the risk for colonic neoplasms, HIV population should be considered as a high-risk group and screened accordingly.展开更多
In this paper, we consider the semilinear equation involving the fractional Laplacian in the Euclidian space R^n:(-△)^α/2u(x) : f(xn)u^p(x), x ∈R^n(0.1)in the subcritical case with 1〈 p〈n+a/n-a.Inste...In this paper, we consider the semilinear equation involving the fractional Laplacian in the Euclidian space R^n:(-△)^α/2u(x) : f(xn)u^p(x), x ∈R^n(0.1)in the subcritical case with 1〈 p〈n+a/n-a.Instead of carrying out direct investigations on pseudo-differential equation (0.1), we first seek its equivalent form in an integral equation as below:u(x)=∫R^nG∞(x, y) f(yn) u^p(y)dy,where G∞(x, y) is the Green's function associated with the fractional Laplacian in R^n. Employing the method of moving planes in integral forms, we are able to derive the nonexistence of positive solutions for (0.2) in the subcritical case. Thanks to the equivalence, same con- clusion is true for (0.1).展开更多
Strongyloides stercoralis,a soil transmitted helminth infection,affects millions with varying prevalence worldwide.A large number of affected hosts are asymptomatic.Symptoms pertaining to pulmonary and gastrointestina...Strongyloides stercoralis,a soil transmitted helminth infection,affects millions with varying prevalence worldwide.A large number of affected hosts are asymptomatic.Symptoms pertaining to pulmonary and gastrointestinal involvement may be present.Manifestations of involvement beyond lung and intestine can be seen with dissemination of infection and lethal hyperinfection.Immunosuppression secondary to use of steroids or other immunosuppressants and coexistence of human T-lymphotropic virus type-1 are the known risk factors for dissemination and hyperinfection.Diagnostic modalities comprise stool examination,serology and molecular testing.Stool tests are inexpensive but are limited by low sensitivity,whereas serologic and molecular tests are more precise but at the expense of higher cost.Treatment with Ivermectin or Albendazole as an alternative is safe and efficacious.We present a rare case of acute pancreatitis secondary to Strongyloides.High index of suspicion in patients specifically from endemic countries of origin and lack of other common etiologies of acute pancreatitis may help in early diagnosis and prompt treatment of this potentially fatal infection.展开更多
Epidermolysis bullosa is a group of genetic disorders with an autosomal dominant or an autosomal recessive mode of inheritance and more than 300 mutations. The disorder is characterized by blistering mucocutaneous les...Epidermolysis bullosa is a group of genetic disorders with an autosomal dominant or an autosomal recessive mode of inheritance and more than 300 mutations. The disorder is characterized by blistering mucocutaneous lesions and has several varying phenotypes due toanchoring defect between the epidermis and dermis. The variation in phenotypic expression depends on the involved structural protein that mediates cell adherence between different layers of the skin. Epidermolysis bullosa can also involve extra-cutaneous sites including eye, nose, ear, upper airway, genitourinary tract and gastrointestinal tract. The most prominent feature of the gastrointestinal tract involvement is development of esophageal stricture. The stricture results from recurrent esophageal mucosal blistering with consequent scarring and most commonly involves the upper esophagus. Here we present a case of a young boy with dominant subtype of dystrophic epidermolysis bullosa who presented with dysphagia, extensive skin blistering and missing nails. Management of an esophageal stricture eventually requires dilatation of the stricture or placement of a gastrostomy tube to keep up with the nutritional requirements. Gastrostomy tube also provides access for esophageal stricture dilatation in cases where antegrade approach through the mouth has failed.展开更多
Throughout the last decade, the use of energy drinks has been increasingly looked upon with caution as potentially dangerous due to their perceived strong concentration of caffeine aside from other substances such as ...Throughout the last decade, the use of energy drinks has been increasingly looked upon with caution as potentially dangerous due to their perceived strong concentration of caffeine aside from other substances such as taurine, guarana, and L-carnitine that are largely unknown to the general public. In addition, a large number of energy drink intoxications have been reported all over the world including cases of seizures and arrhythmias. In this paper, we focus on the effect of energy drinks on the cardiovascular system and whether the current ongoing call for the products' sales and regulation of their contents should continue.展开更多
The endogenous opioid system plays a significant role in the modulation of distress in many psychiatric, neurologic, and neurodevelopmental disorders. Many clinical distress symptoms show similarities to the excitator...The endogenous opioid system plays a significant role in the modulation of distress in many psychiatric, neurologic, and neurodevelopmental disorders. Many clinical distress symptoms show similarities to the excitatory autonomic withdrawal effects in chronic opioid-dependent animals and humans, as well as to the “quasi-morphine withdrawal syndrome” evoked in naive rodents shortly after acute systemic injection of cyclic AMP-phosphodiesterase (cAMP-PDE) inhibitors. These symptoms result from excessive excitatory opioid receptor signaling and increased endorphin release. Pharmacologic analyses of the remarkably plastic bimodal (excitatory/inhibitory) signaling functions of opioid receptors have utilized microelectrode recordings from opioid-sensitive neurons in tissue cultures of mouse sensory ganglia and hot-water tail-flick assays in mice. These studies led to development of specific chemical formulations that switch opioid receptor signaling from an excessively excitatory to a normal inhibitory mode. Critical combinations of cAMP-PDE inhibitors that release endorphins plus specific agents that switch opioid receptors from excitatory Gs-coupled to inhibitory Gi/Go-coupled signaling were shown to attenuate hyperalgesia and distress evoked by diverse chemical stressors in mouse tail-flick assays. Both the “quasi-morphine withdrawal syndrome” in naive rodents as well as the excitatory withdrawal effects in chronic, opioid-dependent animals and humans may be manifestations of a common Endorphinergic Distress Syndrome (EDS). We suggest that many distress symptoms are caused by EDS, a dysfunctional imbalance in the endogenous opioid system, consisting of abnormal endorphin levels, together with opioid receptors predominately in their excitatory mode. Therefore, concomitantly enhancing endogenous opioid release and switching excessive excitatory opioid receptor signaling to inhibitory signaling can attenuate these distress symptoms. Trials of a critically formulated oral preparation, containing both endorphin enhancers and opioid receptor switchers, have resulted in long-term anxiolytic efficacy and enhanced calm and mental clarity in large numbers of individuals with distress symptoms. These endorphinergic formulations may provide treatment for the emotional and physical distress associated with many psychiatric, neurologic, and neurodevelopmental disorders.展开更多
We consider the problem of measuring the electric charge of nanoparticles immersed in a fluid electrolyte. We develop a mathematical framework based on the solution of the nonlinear Poisson-Boltzmann equation to obtai...We consider the problem of measuring the electric charge of nanoparticles immersed in a fluid electrolyte. We develop a mathematical framework based on the solution of the nonlinear Poisson-Boltzmann equation to obtain interaction forces between nanoparticles immersed in a fluid electrolyte and an Atomic Force Microscopy micro spherical probe. This force-separation information is shown explicitly to depend on the charge of the nanoparticle.? This method overcomes the statistical nature of extant methods and renders a charge value for an individual single nanoparticle.展开更多
While the endogenous opioid system has generally been associated with regulation of pain, it also modulates the experience of distress and may play a central role in many psychiatric and neurodevelopmental disorders. ...While the endogenous opioid system has generally been associated with regulation of pain, it also modulates the experience of distress and may play a central role in many psychiatric and neurodevelopmental disorders. Decades of preclinical research on the analgesic effects of endogenous opioids, i.e., endorphins, suggests that opioid receptors have plastic bimodal (inhibitory/excitatory) properties that may explain conflicting findings in clinical research. An exploratory study with 60 healthy volunteer participants, using a cold pressor-induced pain paradigm, found evidence that a combination of a nutraceutical agent that enhances endorphin release (Endorphin Enhancer) with one that switches opioid receptors from an excitatory to inhibitory mode (Opioid Receptor Switcher) not only increases pain tolerance but also reduces emotional and physical distress. This discovery led to clinical application of a critically formulated endorphinergic treatment in 203 case studies over a two-year period. Findings revealed the remarkable clinical efficacy and safety of this treatment in the relief of chronic emotional and physical distress, including anxiety, anger, depression, cravings, and hyperalgesia, as well as enhancement of well-being, productivity, mental clarity, relationships, and an adaptive response to life’s stresses. These studies provide new insights into the role of endogenous opioid system imbalances in the development, treatment, and prevention of dysfunctional emotional and physical distress. We postulate that an Endorphinergic Distress Syndrome (EDS) consists of abnormal endorphin levels together with opioid receptors predominately in their excitatory mode. EDS may account for many core distress symptoms associated with chronic anxiety, addictions, pain, as well as affective personality, autism spectrum, attention-deficit, and distress-related medical problems. Our research has led to new endorphinergic formulations, combining Endorphin Enhancers, such as caffeine, with Opioid Receptor Switchers, such as n-acetylcysteine, for the relief of emotional and physical distress. Our studies also provide a novel method to reverse the anxiogenic effects of caffeine and related hyperexcitatory substances.展开更多
In the Simulated Annealing algorithm applied to the Traveling Salesman Problem, the total tour length decreases with temperature. Empirical observation shows that the tours become more structured as the temperature de...In the Simulated Annealing algorithm applied to the Traveling Salesman Problem, the total tour length decreases with temperature. Empirical observation shows that the tours become more structured as the temperature decreases. We quantify this fact by proposing the use of the Shannon information content of the probability distribution function of inter–city step lengths. We find that information increases as the Simulated Annealing temperature decreases. We also propose a practical use of this insight to improve the standard algorithm by switching, at the end of the algorithm, the cost function from the total length to information content. In this way, the final tour should not only be shorter, but also smoother.展开更多
Objectives: To examine the cross-sectional associations of the separate subscales of the Perceived Stress Scale (PSS) and tests measuring cognitive domains in older adults. Methods: 897 adults over the age of 70 free ...Objectives: To examine the cross-sectional associations of the separate subscales of the Perceived Stress Scale (PSS) and tests measuring cognitive domains in older adults. Methods: 897 adults over the age of 70 free of amnestic mild cognitive impairment and dementia and enrolled in the Einstein Aging Study made up the study sample. The PSS-14 was used to measure stress. Three cognitive domains (language, episodic memory, and frontal-executive) had previously been found using principle component analysis. Linear regression analyses were used to determine the relationship between the PSS subscales and cognitive domain function. Results: The study sample had a mean age of 79.1 years and 62.8% were female. Bivariate correlations show that the PSS-14 positively worded subscale of the PSS (PSS-PW) was significantly associated with all three cognitive domains (language: r = -0.15, p < 0.001;episodic memory: r = -0.16, p < 0.001;frontal-executive: r = -0.21, p <0.001) while the negatively worded subscale of the PSS (PSS-NW) was not significantly associated with any cognitive domain. In linear regression analyses adjusted for age, white race, gender, years of education, and depressive symptoms, the PSS-PW remained significantly associated with each of the cognitive domains. The PSS-NW was not associated with any cognitive domains in any model. The PSS-14 was significantly associated with language and episodic memory, but not the frontal-executive domain. Conclusion: Worse PSS-PW scores are associated with reduced cognitive function in the executive, memory, and language domains in nondemented older adults. The PSS-PW subscale correlated better with cognitive function than the overall PSS-14. Future research should evaluate the temporality of the association and if stress reduction therapies improve cognitive performance.展开更多
The formation of nanoscale water capillary bridges(WCBs) between chemically heterogeneous(patchy) surfaces plays an important role in different scientific and engineering applications, including nanolithography, collo...The formation of nanoscale water capillary bridges(WCBs) between chemically heterogeneous(patchy) surfaces plays an important role in different scientific and engineering applications, including nanolithography, colloidal aggregation, and bioinspired adhesion. However, the properties of WCB of nanoscale dimensions remain unclear. Using molecular dynamics simulations, we investigate the geometrical and thermodynamic properties of WCB confined between chemically heterogeneous surfaces composed of circular hydrophilic patches on a hydrophobic background. We find that macroscopic capillary theory provides a good description of the WCB geometry and forces induced by the WCB on the confining surfaces even in the case of surface patches with diameters of only 4 nm. Upon stretching, the WCB contact angle changes from hydrophobic-like values(θ > 90°) to hydrophilic-like values(θ < 90°) until it finally breaks down into two droplets at wall separations of ~9–10 nm. We also show that the studied nanoscale WCB can be used to store relevant amounts of energy EPand explore how the walls patch geometry can be improved in order to maximize EP. Our findings show that nanoscale WCB can, in principle, be exploited for the design of clean energy storage devices as well as actuators that respond to changes in relative humidity. The present results can also be of crucial importance for the understanding of water transport in nanoporous media and nanoscale engineering systems.展开更多
In this paper, we propose a unified differential operator method to study mechanical vibrations, solving inhomogeneous linear ordinary differential equations with constant coefficients. The main advantage of this new ...In this paper, we propose a unified differential operator method to study mechanical vibrations, solving inhomogeneous linear ordinary differential equations with constant coefficients. The main advantage of this new method is that the differential operator D in the numerator of the fraction has no effect on input functions (i.e., the derivative operation is removed) because we take the fraction as a whole part in the partial fraction expansion. The method in various variants is widely implemented in related fields in mechanics and engineering. We also point out that the same mistakes in the differential operator method are found in the related references [1-4].展开更多
VEGF (Vascular endothelial growth factor) signaling is critical for endothelial cell survival and maintenance of the vasculature. Deregulation of VEGF signaling contributes to the physiopathology of many diseases. H...VEGF (Vascular endothelial growth factor) signaling is critical for endothelial cell survival and maintenance of the vasculature. Deregulation of VEGF signaling contributes to the physiopathology of many diseases. However, the ways in which infection with Paracoccidioides brasiliensis affects VEGF signaling and the influence of immunization with rPb27 (recombinant protein Pb27) on VEGF signaling have not yet been studied. Animals were immunized with rPb27 and subsequently infected with a virulent strain of P. brasiliensis. The fungal load was evaluated by measuring CFU (colony-forming unit) and histology was performed to evaluate the inflammatory reaction. At the two time points analyzed, the PC (positive control) and TREAT (treated) animals had decreased levels of pulmonary VEGF compared to basal levels. However, in the immunized (Pb27) and treated mice (Pb27 + TREAT), VEGF expression remained unchanged after infection. In the case of VEGFR-2, the Pb27 and Pb27 + TREAT groups showed increased levels of expression. Regarding the levels of the eNOS enzyme, only the Pb27 group did not reduce the expression levels relative to baseline. The immunization with rPb27 kept VEGF signaling, NO production and increased VEGFR-2 expression, after infection with P. brasiliensis. Thus, the authors infer that immunization with rPb27 protects mice from the disruption of VEGF signaling in Paracoccidioides brasiliensis infection.展开更多
文摘This review focuses on major contemporary empirical studies that examine both the physical and regulatory sides of climate risk. These studies explore how climate risk affects firms’ operating performance and leverage, stock and bond valuation, cost of capital, and managerial behavior. We also discuss how the effect of climate risk on real estate markets depends on individuals’ beliefs about climate change. Furthermore, we summarize papers on climate risk activism and how firms can employ financial devices and technology to mitigate their climate risk. Finally, we make some recommendations for further research areas.
基金supported by NSF Grant DMS-0604638Li partially supported by NSF Grant DMS-0401174
文摘We classify all positive solutions for the following integral system:{ui(x)=∫Rn1/│x-y│^n-α fi(u(y))dy,x∈R^n,i=1,…,m,0〈α〈n,and u(x)=(u1(x),u2(x)…,um(x)).Here fi(u), 1 ≤ i ≤m, monotone nondecreasing are real-valued functions of homogeneous degree n+α/n-α and are monotone nondecreasing with respect to all the independent variables U1, u2, ..., urn.In the special case n ≥ 3 and α = 2. we show that the above system is equivalent to thefollowing elliptic PDE system:This system is closely related to the stationary SchrSdinger system with critical exponents for Bose-Einstein condensate
文摘Degenerative disease of the lumbar spine is a common and increasingly prevalent condition that is often implicated as the primary reason for chronic low back pain and the leading cause of disability in the western world. Surgical management of lumbar degenerative disease has historically been approached by way of open surgical procedures aimed at decompressing and/or stabilizing the lumbar spine. Advances in technology andsurgical instrumentation have led to minimally invasive surgical techniques being developed and increasingly used in the treatment of lumbar degenerative disease. Compared to the traditional open spine surgery, minimally invasive techniques require smaller incisions and decrease approach-related morbidity by avoiding muscle crush injury by self-retaining retractors, preventing the disruption of tendon attachment sites of important muscles at the spinous processes, using known anatomic neurovascular and muscle planes, and minimizing collateral soft-tissue injury by limiting the width of the surgical corridor. The theoretical benefits of minimally invasive surgery over traditional open surgery include reduced blood loss, decreased postoperative pain and narcotics use, shorter hospital length of stay, faster recover and quicker return to work and normal activity. This paper describes the different minimally invasive techniques that are currently available for the treatment of degenerative disease of the lumbar spine.
文摘Ejaculatory dysfunction is a highly prevalent clinical condition that may be classified along a continuum that ranges from premature ejaculation (PE), through retarded or delayed ejaculation (DE), to complete anejaculation (AE). Retrograde ejaculation (RE) represents a distinct entity in which ejaculate is expelled either partially or completely into the bladder. While DE and PE are significant sources of sexual dissatisfaction among men and their partners, patients with these disorders retain normal fertility in most cases. Conversely, men with AE and RE are unable to deliver sperm into the female genital tract and are therefore rendered subfertile. Therefore, in reviewing ejaculatory disorders as they relate to fertility, this paper will primarily focus on the diagnosis and management of AE and RE. Physiology, diagnostic strategies, pharmacological treatments, and procedural interventions relevant to AE and RE are discussed.
文摘AIM:To evaluate if human immunodeficiency virus (HIV) population is getting adequate screening for colon cancer in the highly active anti-retroviral treatment (HAART) era with improved longevity, and the prevalence of polyps and adenomas in this population, when compared with the general population. METHODS:We conducted retrospective chart review of average-risk HIV population for colon cancer attending our infectious disease clinic. Individuals who underwent diagnostic colonoscopy were excluded. We extracted various demographic, HIV disease-specific and colonoscopy data including histo-pathological reports in the last 10 years. Total population was divided into a study group, who underwent screening colonoscopy and a control group who did not. We analyzed data using standard statistical methods and software. RESULTS:We found that 25% of average-risk HIVinfected population was screened for colon cancer using colonoscopy. There was no difference in gender and ethnic distribution between the groups. We foundwider distribution of age (50-84 years with mean 56 years) in the control group when compared to (50-73 years with mean 58 years) the study group. However, there were 89% of subjects with well-controlled HIV disease measured by HIV RNA copies of < 75 in the study group when compared with 70% in the control group (P < 0.0001). We noticed polyp detection rate of 55% and adenoma detection rate of 32% in HIV population. CONCLUSION:It is unclear whether HIV or HAART medications play a role in increased prevalence of adenomas. We suggest that when estimating the risk for colonic neoplasms, HIV population should be considered as a high-risk group and screened accordingly.
文摘In this paper, we consider the semilinear equation involving the fractional Laplacian in the Euclidian space R^n:(-△)^α/2u(x) : f(xn)u^p(x), x ∈R^n(0.1)in the subcritical case with 1〈 p〈n+a/n-a.Instead of carrying out direct investigations on pseudo-differential equation (0.1), we first seek its equivalent form in an integral equation as below:u(x)=∫R^nG∞(x, y) f(yn) u^p(y)dy,where G∞(x, y) is the Green's function associated with the fractional Laplacian in R^n. Employing the method of moving planes in integral forms, we are able to derive the nonexistence of positive solutions for (0.2) in the subcritical case. Thanks to the equivalence, same con- clusion is true for (0.1).
文摘Strongyloides stercoralis,a soil transmitted helminth infection,affects millions with varying prevalence worldwide.A large number of affected hosts are asymptomatic.Symptoms pertaining to pulmonary and gastrointestinal involvement may be present.Manifestations of involvement beyond lung and intestine can be seen with dissemination of infection and lethal hyperinfection.Immunosuppression secondary to use of steroids or other immunosuppressants and coexistence of human T-lymphotropic virus type-1 are the known risk factors for dissemination and hyperinfection.Diagnostic modalities comprise stool examination,serology and molecular testing.Stool tests are inexpensive but are limited by low sensitivity,whereas serologic and molecular tests are more precise but at the expense of higher cost.Treatment with Ivermectin or Albendazole as an alternative is safe and efficacious.We present a rare case of acute pancreatitis secondary to Strongyloides.High index of suspicion in patients specifically from endemic countries of origin and lack of other common etiologies of acute pancreatitis may help in early diagnosis and prompt treatment of this potentially fatal infection.
文摘Epidermolysis bullosa is a group of genetic disorders with an autosomal dominant or an autosomal recessive mode of inheritance and more than 300 mutations. The disorder is characterized by blistering mucocutaneous lesions and has several varying phenotypes due toanchoring defect between the epidermis and dermis. The variation in phenotypic expression depends on the involved structural protein that mediates cell adherence between different layers of the skin. Epidermolysis bullosa can also involve extra-cutaneous sites including eye, nose, ear, upper airway, genitourinary tract and gastrointestinal tract. The most prominent feature of the gastrointestinal tract involvement is development of esophageal stricture. The stricture results from recurrent esophageal mucosal blistering with consequent scarring and most commonly involves the upper esophagus. Here we present a case of a young boy with dominant subtype of dystrophic epidermolysis bullosa who presented with dysphagia, extensive skin blistering and missing nails. Management of an esophageal stricture eventually requires dilatation of the stricture or placement of a gastrostomy tube to keep up with the nutritional requirements. Gastrostomy tube also provides access for esophageal stricture dilatation in cases where antegrade approach through the mouth has failed.
文摘Throughout the last decade, the use of energy drinks has been increasingly looked upon with caution as potentially dangerous due to their perceived strong concentration of caffeine aside from other substances such as taurine, guarana, and L-carnitine that are largely unknown to the general public. In addition, a large number of energy drink intoxications have been reported all over the world including cases of seizures and arrhythmias. In this paper, we focus on the effect of energy drinks on the cardiovascular system and whether the current ongoing call for the products' sales and regulation of their contents should continue.
文摘The endogenous opioid system plays a significant role in the modulation of distress in many psychiatric, neurologic, and neurodevelopmental disorders. Many clinical distress symptoms show similarities to the excitatory autonomic withdrawal effects in chronic opioid-dependent animals and humans, as well as to the “quasi-morphine withdrawal syndrome” evoked in naive rodents shortly after acute systemic injection of cyclic AMP-phosphodiesterase (cAMP-PDE) inhibitors. These symptoms result from excessive excitatory opioid receptor signaling and increased endorphin release. Pharmacologic analyses of the remarkably plastic bimodal (excitatory/inhibitory) signaling functions of opioid receptors have utilized microelectrode recordings from opioid-sensitive neurons in tissue cultures of mouse sensory ganglia and hot-water tail-flick assays in mice. These studies led to development of specific chemical formulations that switch opioid receptor signaling from an excessively excitatory to a normal inhibitory mode. Critical combinations of cAMP-PDE inhibitors that release endorphins plus specific agents that switch opioid receptors from excitatory Gs-coupled to inhibitory Gi/Go-coupled signaling were shown to attenuate hyperalgesia and distress evoked by diverse chemical stressors in mouse tail-flick assays. Both the “quasi-morphine withdrawal syndrome” in naive rodents as well as the excitatory withdrawal effects in chronic, opioid-dependent animals and humans may be manifestations of a common Endorphinergic Distress Syndrome (EDS). We suggest that many distress symptoms are caused by EDS, a dysfunctional imbalance in the endogenous opioid system, consisting of abnormal endorphin levels, together with opioid receptors predominately in their excitatory mode. Therefore, concomitantly enhancing endogenous opioid release and switching excessive excitatory opioid receptor signaling to inhibitory signaling can attenuate these distress symptoms. Trials of a critically formulated oral preparation, containing both endorphin enhancers and opioid receptor switchers, have resulted in long-term anxiolytic efficacy and enhanced calm and mental clarity in large numbers of individuals with distress symptoms. These endorphinergic formulations may provide treatment for the emotional and physical distress associated with many psychiatric, neurologic, and neurodevelopmental disorders.
文摘We consider the problem of measuring the electric charge of nanoparticles immersed in a fluid electrolyte. We develop a mathematical framework based on the solution of the nonlinear Poisson-Boltzmann equation to obtain interaction forces between nanoparticles immersed in a fluid electrolyte and an Atomic Force Microscopy micro spherical probe. This force-separation information is shown explicitly to depend on the charge of the nanoparticle.? This method overcomes the statistical nature of extant methods and renders a charge value for an individual single nanoparticle.
文摘While the endogenous opioid system has generally been associated with regulation of pain, it also modulates the experience of distress and may play a central role in many psychiatric and neurodevelopmental disorders. Decades of preclinical research on the analgesic effects of endogenous opioids, i.e., endorphins, suggests that opioid receptors have plastic bimodal (inhibitory/excitatory) properties that may explain conflicting findings in clinical research. An exploratory study with 60 healthy volunteer participants, using a cold pressor-induced pain paradigm, found evidence that a combination of a nutraceutical agent that enhances endorphin release (Endorphin Enhancer) with one that switches opioid receptors from an excitatory to inhibitory mode (Opioid Receptor Switcher) not only increases pain tolerance but also reduces emotional and physical distress. This discovery led to clinical application of a critically formulated endorphinergic treatment in 203 case studies over a two-year period. Findings revealed the remarkable clinical efficacy and safety of this treatment in the relief of chronic emotional and physical distress, including anxiety, anger, depression, cravings, and hyperalgesia, as well as enhancement of well-being, productivity, mental clarity, relationships, and an adaptive response to life’s stresses. These studies provide new insights into the role of endogenous opioid system imbalances in the development, treatment, and prevention of dysfunctional emotional and physical distress. We postulate that an Endorphinergic Distress Syndrome (EDS) consists of abnormal endorphin levels together with opioid receptors predominately in their excitatory mode. EDS may account for many core distress symptoms associated with chronic anxiety, addictions, pain, as well as affective personality, autism spectrum, attention-deficit, and distress-related medical problems. Our research has led to new endorphinergic formulations, combining Endorphin Enhancers, such as caffeine, with Opioid Receptor Switchers, such as n-acetylcysteine, for the relief of emotional and physical distress. Our studies also provide a novel method to reverse the anxiogenic effects of caffeine and related hyperexcitatory substances.
文摘In the Simulated Annealing algorithm applied to the Traveling Salesman Problem, the total tour length decreases with temperature. Empirical observation shows that the tours become more structured as the temperature decreases. We quantify this fact by proposing the use of the Shannon information content of the probability distribution function of inter–city step lengths. We find that information increases as the Simulated Annealing temperature decreases. We also propose a practical use of this insight to improve the standard algorithm by switching, at the end of the algorithm, the cost function from the total length to information content. In this way, the final tour should not only be shorter, but also smoother.
文摘Objectives: To examine the cross-sectional associations of the separate subscales of the Perceived Stress Scale (PSS) and tests measuring cognitive domains in older adults. Methods: 897 adults over the age of 70 free of amnestic mild cognitive impairment and dementia and enrolled in the Einstein Aging Study made up the study sample. The PSS-14 was used to measure stress. Three cognitive domains (language, episodic memory, and frontal-executive) had previously been found using principle component analysis. Linear regression analyses were used to determine the relationship between the PSS subscales and cognitive domain function. Results: The study sample had a mean age of 79.1 years and 62.8% were female. Bivariate correlations show that the PSS-14 positively worded subscale of the PSS (PSS-PW) was significantly associated with all three cognitive domains (language: r = -0.15, p < 0.001;episodic memory: r = -0.16, p < 0.001;frontal-executive: r = -0.21, p <0.001) while the negatively worded subscale of the PSS (PSS-NW) was not significantly associated with any cognitive domain. In linear regression analyses adjusted for age, white race, gender, years of education, and depressive symptoms, the PSS-PW remained significantly associated with each of the cognitive domains. The PSS-NW was not associated with any cognitive domains in any model. The PSS-14 was significantly associated with language and episodic memory, but not the frontal-executive domain. Conclusion: Worse PSS-PW scores are associated with reduced cognitive function in the executive, memory, and language domains in nondemented older adults. The PSS-PW subscale correlated better with cognitive function than the overall PSS-14. Future research should evaluate the temporality of the association and if stress reduction therapies improve cognitive performance.
基金Project support by the National Natural Science Foundation of China(Grant Nos.11525520 and 11935002)the National Key Research and Development Program of China(Grant No.2016YFA0300901).
文摘The formation of nanoscale water capillary bridges(WCBs) between chemically heterogeneous(patchy) surfaces plays an important role in different scientific and engineering applications, including nanolithography, colloidal aggregation, and bioinspired adhesion. However, the properties of WCB of nanoscale dimensions remain unclear. Using molecular dynamics simulations, we investigate the geometrical and thermodynamic properties of WCB confined between chemically heterogeneous surfaces composed of circular hydrophilic patches on a hydrophobic background. We find that macroscopic capillary theory provides a good description of the WCB geometry and forces induced by the WCB on the confining surfaces even in the case of surface patches with diameters of only 4 nm. Upon stretching, the WCB contact angle changes from hydrophobic-like values(θ > 90°) to hydrophilic-like values(θ < 90°) until it finally breaks down into two droplets at wall separations of ~9–10 nm. We also show that the studied nanoscale WCB can be used to store relevant amounts of energy EPand explore how the walls patch geometry can be improved in order to maximize EP. Our findings show that nanoscale WCB can, in principle, be exploited for the design of clean energy storage devices as well as actuators that respond to changes in relative humidity. The present results can also be of crucial importance for the understanding of water transport in nanoporous media and nanoscale engineering systems.
文摘In this paper, we propose a unified differential operator method to study mechanical vibrations, solving inhomogeneous linear ordinary differential equations with constant coefficients. The main advantage of this new method is that the differential operator D in the numerator of the fraction has no effect on input functions (i.e., the derivative operation is removed) because we take the fraction as a whole part in the partial fraction expansion. The method in various variants is widely implemented in related fields in mechanics and engineering. We also point out that the same mistakes in the differential operator method are found in the related references [1-4].
文摘VEGF (Vascular endothelial growth factor) signaling is critical for endothelial cell survival and maintenance of the vasculature. Deregulation of VEGF signaling contributes to the physiopathology of many diseases. However, the ways in which infection with Paracoccidioides brasiliensis affects VEGF signaling and the influence of immunization with rPb27 (recombinant protein Pb27) on VEGF signaling have not yet been studied. Animals were immunized with rPb27 and subsequently infected with a virulent strain of P. brasiliensis. The fungal load was evaluated by measuring CFU (colony-forming unit) and histology was performed to evaluate the inflammatory reaction. At the two time points analyzed, the PC (positive control) and TREAT (treated) animals had decreased levels of pulmonary VEGF compared to basal levels. However, in the immunized (Pb27) and treated mice (Pb27 + TREAT), VEGF expression remained unchanged after infection. In the case of VEGFR-2, the Pb27 and Pb27 + TREAT groups showed increased levels of expression. Regarding the levels of the eNOS enzyme, only the Pb27 group did not reduce the expression levels relative to baseline. The immunization with rPb27 kept VEGF signaling, NO production and increased VEGFR-2 expression, after infection with P. brasiliensis. Thus, the authors infer that immunization with rPb27 protects mice from the disruption of VEGF signaling in Paracoccidioides brasiliensis infection.