Clinical efficacy and mechanism study of mid-frequency anti-snoring device in treating moderate obstructive sleep apnea-hypopnea syndrome

BACKGROUND Obstructive sleep apnea-hypopnea syndrome(OSAHS)is primarily caused by airway obstruction due to narrowing and blockage in the nasal and nasopha-ryngeal,oropharyngeal,soft palate,and tongue base areas.The mid-frequency anti-snoring device is a new technology based on sublingual nerve stimulation.Its principle is to improve the degree of oropharyngeal airway stenosis in OSAHS patients under mid-frequency wave stimulation.Nevertheless,there is a lack of clinical application and imaging evidence.METHODS We selected 50 patients diagnosed with moderate OSAHS in our hospital between July 2022 and August 2023.They underwent a 4-wk treatment regimen involving the mid-frequency anti-snoring device during nighttime sleep.Following the treatment,we monitored and assessed the sleep apnea quality of life index and Epworth Sleepiness Scale scores.Additionally,we performed computed tomo-graphy scans of the oropharynx in the awake state,during snoring,and while using the mid-frequency anti-snoring device.Cross-sectional area measurements in different states were taken at the narrowest airway point in the soft palate posterior and retrolingual areas.RESULTS Compared to pretreatment measurements,patients exhibited a significant reduction in the apnea-hypopnea index,the percentage of time with oxygen saturation below 90%,snoring frequency,and the duration of the most prolonged apnea event.The lowest oxygen saturation showed a notable increase,and both sleep apnea quality of life index and Epworth Sleepiness Scale scores improved.Oropharyngeal computed tomography scans revealed that in OSAHS patients cross-sectional areas of the oropharyngeal airway in the soft palate posterior area and retrolingual area decreased during snoring compared to the awake state.Conversely,during mid-frequency anti-snoring device treatment,these areas increased compared to snoring.CONCLUSION The mid-frequency anti-snoring device demonstrates the potential to enhance various sleep parameters in patients with moderate OSAHS,thereby improving their quality of life and reducing daytime sleepiness.These therapeutic effects are attributed to the device’s ability to ameliorate the narrowing of the oropharynx in OSAHS patients.

Correlation between type 2 diabetes mellitus remission and intrapancreatic fat deposition

BACKGROUND Intrapancreatic fat deposition(IPFD)exerts a significant negative impact on patients with type 2 diabetes mellitus(T2DM),accelerates disease deterioration,and may lead to impairedβ-cell quality and function.AIM To investigate the correlation between T2DM remission and IPFD.METHODS We enrolled 80 abdominally obese patients with T2DM admitted to our institution from January 2019 to October 2023,including 40 patients with weight lossinduced T2DM remission(research group)and 40 patients with short-term intensive insulin therapy-induced T2DM remission(control group).We comparatively analyzed improvements in IPFD[differential computed tomography(CT)values of the spleen and pancreas and average CT value of the pancreas];levels of fasting blood glucose(FBG),2-h postprandial blood glucose(2hPBG),and insulin;and homeostasis model assessment of insulin resistance(HOMA-IR)scores.Correlation analysis was performed to explore the association between T2DM remission and IPFD.RESULTS After treatment,the differential CT values of the spleen and pancreas,FBG,2hPBG,and HOMA-IR in the research group were significantly lower than those before treatment and in the control group,and the average CT value of the pancreas and insulin levels were significantly higher.Correlation analysis revealed that the greater the T2DM remission,the lower the amount of IPFD.

Research progresses of dual-layer spectral detector CT for preoperative evaluation on colorectal cancer

Dual-layer spectral detector CT is a new spectrum CT imaging technology based on detector being able to obtain both images similar to true plain and spectral images in one time scanning.The reconstructed multi-parameter spectral images can not only improve image quality,enhance tissue contrast,increase the visualization and detection ability of occult lesions,but also provide qualitative and quantitative analysis of the lesions,so as to provide more imaging information and multi-dimensional diagnostic basis.The research progresses of dual-layer spectral detector CT for preoperative evaluation on colorectal cancer were reviewed in this article.

Evaluation of CdZnTe spectrometer performance in measuring energy spectra during interventional radiology procedure

Interventional radiology has been beneficial for patients for over 30 years of age with the combination of diagnostic and therapeutic methods. The radiation affecting occupationally exposed workers should be evaluated by means of the energy spectra and flux of X-rays in the treatment room. The present study aims to obtain the energy spectra of interventional procedures and study the capability of some detectors to evaluate the dose in interventional procedures. These measurements were taken by silicon-drift, CdTe, and CdZnTe detectors. The energy spectra were corrected by the energy-response curve of each detector. The energy-response curves of silicon-drift and CdTe detectors provided by the manufacturers specification were used. The energy response of the CdZnTe detector was measured by 133Ba and 152Eu γ sources. The experimental data were compared with the simulation results, and their perfect agreement provides a way to correct the energy or dose response, which can be used for the personal dosimeter developed by our group. Moreover, the measured energy spectra can be used in individual radiation protection. The present study shows that the CdZnTe detector is a good candidate detector in interventional procedures.

Application of a jigsaw puzzle flap based on free-style perforator to repair large scalp defects after tumor resection:A case series

Background:Reconstruction of large scalp defects after tumor resection is common and challenging.Free skin grafting or free flap transfer is always performed.However,these techniques can result in poor functional and cosmetic outcomes.Methods:In the Second Affiliated Hospital of Soochow University and the Second Affiliated Hospital of Chengdu Medical College,35 patients underwent jigsaw puzzle flap procedures based on a free-style perforator to repair large scalp defects after tumor resection from May 2013 to November 2022.The key to this procedure was to divide a large defect into several smaller parts that correspond to adjacent free-style perforators around the scalp defect.The free-style perforator flaps were designed in different ways,such as propeller flaps,rotation flaps,and V-Y advancement flaps,which were pedicled with free-style perforators.All of the small flaps were then mobilized to the defect and sutured to each other to create a new,large jigsaw puzzle-like flap to cover the large scalp defect.Finally,all the donor sites were closed directly.Results:Overall,35 patients were treated.The average defect size was 72 cm^(2)(range,25-91 cm^(2)).All flaps had a satisfactory appearance after follow-up periods of 6 months-10 years.Local tumor recurrence occurred in one case.Conclusion:The application of a jigsaw puzzle flap based on a free-style perforator is a suitable option for the reconstruction of large scalp defects after resection,yielding satisfactory functional and cosmetic results.

A novel traditional Chinese medicine combination for radiation

Objective:To formulate an efficacious radioprotective combination of Chinese medicines with minimal toxicity.Methods:Aqueous and alcoholic extracts from 38 traditional Chinese herbs were prepared.To produce drugcontaining sera,rats received six doses of each extract via oral gavage at 12-h intervals.Subsequently,human lung epithelial BEAS-2B cells were cultured in these drug-containing sera.The cell viability was assessed after different doses of irradiation to identify the radioprotective effects of Chinese herbal extracts.The efficacy of a selected Chinese herbal extract combination was further confirmed through cell viability analysis via in vitro colony formation and survival rate assessments in C57BL/6 mice post-irradiation.Results:Extracts from Angelicae Sinensis Radix(ASR;two extracts),Citri Reticulatae Pericarpium(CRP),Platycladi Cacumen(PC),Schisandrae chinensis Fructus(SF),Scutellariae Radix(SR),and Glycyrrhizae Radix et Rhizome(GRR)demonstrated radioprotective effects.The combination of the seven Chinese herbal extracts notably increased the survival and viability of the BEAS-2B cells exposed to varying doses of X-rays.Moreover,the group of mice receiving Chinese medicine combination and irradiation exhibited prolonged survival after exposure to 6.5 Gy Xrays with a median survival of(14=2)d compared to(11=2)d in the irradiated group without the herbal treatment.Additionally,the Chinese medicine combination group displayed a significantly higher 28 d survival rate(30%)compared to the irradiation-only group(16.6%,P<0.05).Conclusion:The novel combination of Chinese herbal extracts from ASR,CRP,PC,SF,SR,and GRR has the potential for radiation protection applications.

Lightweight Classification Network for Pulmonary Tuberculosis Based on CT Images

With the continuous development of medical informatics and digital diagnosis,the classification of tuberculosis(TB)cases from computed tomography(CT)images of the lung based on deep learning is an important guiding aid in clinical diagnosis and treatment.Due to its potential application in medical image classification,this task has received extensive research attention.Existing related neural network techniques are still challenging in terms of feature extraction of global contextual information of images and network complexity in achieving image classification.To address these issues,this paper proposes a lightweight medical image classification network based on a combination of Transformer and convolutional neural network(CNN)for the classification of TB cases from lung CT.The method mainly consists of a fusion of the CNN module and the Transformer module,exploiting the advantages of both in order to accomplish a more accurate classification task.On the one hand,the CNN branch supplements the Transformer branch with basic local feature information in the low level;on the other hand,in the middle and high levels of the model,the CNN branch can also provide the Transformer architecture with different local and global feature information to the Transformer architecture to enhance the ability of the model to obtain feature information and improve the accuracy of image classification.A shortcut is used in each module of the network to solve the problem of poor model results due to gradient divergence and to optimize the effectiveness of TB classification.The proposed lightweight model can well solve the problem of long training time in the process of TB classification of lung CT and improve the speed of classification.The proposed method was validated on a CT image data set provided by the First Hospital of Lanzhou University.The experimental results show that the proposed lightweight classification network for TB based on CT medical images of lungs can fully extract the feature information of the input images and obtain high-accuracy classification results.

Biological effects of low-dose-rate irradiation of pancreatic carcinoma cells in vitro using ^(125)I seeds

AIM:To determine the mechanism of the radiationinduced biological effects of 125I seeds on pancreatic carcinoma cells in vitro.METHODS:SW1990 and PANC-1 pancreatic cancer cell lines were cultured in DMEM in a suitable environment.Gray’s model of iodine-125(125I)seed irradiation was used.In vitro,exponential phase SW1990,and PANC-1cells were exposed to 0,2,4,6,and 8 Gy using 125I radioactive seeds,with an initial dose rate of 12.13c Gy/h.A clonogenic survival experiment was performed to observe the ability of the cells to maintain their clonogenic capacity and to form colonies.Cell-cycle and apoptosis analyses were conducted to detect the apoptosis percentage in the SW1990 and PANC-1 cells.DNA synthesis was measured via a tritiated thymidine(3H-Td R)incorporation experiment.After continuous low-dose-rate irradiation with 125I radioactive seeds,the survival fractions at 2 Gy(SF2),percentage apoptosis,and cell cycle phases of the SW1990 and PANC-1 pancreatic cancer cell lines were calculated and compared.RESULTS:The survival fractions of the PANC-1 andSW1990 cells irradiated with 125I seeds decreased exponentially as the dose increased.No significant difference in SF2 was observed between SW1990 and PANC-1 cells(0.766±0.063 vs 0.729±0.045,P<0.05).The 125I seeds induced a higher percentage of apoptosis than that observed in the control in both the SW1990and PANC-1 cells.The rate of apoptosis increased with increasing radiation dosage.The percentage of apoptosis was slightly higher in the SW1990 cells than in the PANC-1 cells.Dose-dependent G2/M cellcycle arrest was observed after 125I seed irradiation,with a peak value at 6 Gy.As the dose increased,the percentage of G2/M cell cycle arrest increased in both cell lines,whereas the rate of DNA incorporation decreased.In the 3H-Td R incorporation experiment,the dosimetry results of both the SW1990 and PANC-1cells decreased as the radiation dose increased,with a minimum at 6 Gy.There were no significant differences in the dosimetry results of the two cell lines when they were exposed to the same dose of radiation.CONCLUSION:The pancreatic cancer cell-killing effects induced by 125I radioactive seeds mainly occurred via apoptosis and G2/M cell cycle arrest.

Multiple Risk Factor Clustering and Risk of Hypertension in the Mongolian Ethnic Population of China

Objective To evaluate whether the clustering of risk factors, both environmental and genetic, increases the risk of essential hypertension （EH） and the accumulation of risk factors influences the blood pressure level in normotensives. Methods On the basis of a prevalence survey, 501 subjects of Mongolian ethnicity （243 hypertensives and 258 normotensives） who were not related to each other were selected to conduct a case-control study. All subjects were interviewed with questionnaires and their blood specimens were collected. Renin gene insertion/deletion （I/D） polymorphism, a new genetic marker, was genotyped with PCR and polyacrylamide gel electrophoresis. Results Overweight, alcohol consumption, and renin gene I/D polymorphism were significant risk factors of EH （P〈0.05）. The odds ratios （OR） for the number of risk factors were 2.39 （95%CI： 0.98-6.74） for one risk factor, 5.03 （95%CI： 2.06-14.18） for two, and 6.09 （95%CI： 1.85-22.38） for three respectively after adjusting for age and sex. In normotensives, age- and sex-adjusted mean blood pressures increased with more accumulation of risk factors. However, there were no significant differences among the different blood pressure levels according to the number of risk factors （P〉0.05）. Conclusion Overweight, alcohol consumption, and renin gene I/D polymorphism are risk factors of EH in the Mongolian ethnic population of China. The accumulation of the risk factors causes a sharp increase of the risk of EH.

Comparison of neutron energy spectrum unfolding methods and evaluation of rationality criteria

The neutron energy spectrum was measured using a Bonner sphere spectrometer at six locations inside the containment vessel of a nuclear reactor at the Qinshan nuclear power plant. The structures of the neutron spectra obtained by the maximum entropy, iteration, and genetic algorithm methods were consistent with one another and could be interpreted as the spectral superposition of different energy regions. The characteristic parameters of the neutron spectrum, including the fluence rate,average energy, and neutron ambient dose equivalent rate H^(*)(10), were in good agreement among the three methods. In addition, an LB6411 neutron ambient dose equivalent meter was employed to obtain the H^(*)(10) directly for comparison.These findings indicate that neutron spectrum unfolding methods can be used to overcome the problems associated with the response functions of dosimeters to provide more accurate H^(*)(10) values. In this study, the following three evaluation criteria were systematically addressed to ensure the accuracy of the unfolded spectra: count rates of the inverse solutions,neutron spectrum structures, and comparison of key parameters.

Performance of a plastic scintillation fiber dosimeter based on different photoelectric devices

The photoelectric device of a scintillation dosimeter converts photons produced by radiation into an electrical signal.Its features directly determine the overall performance of the dosimeter.For a plastic scintillation fiber dosimeter(PSFD)with a current readout mode,systematic studies of the stability and light-dose response were performed for the photomultiplier tube(PMT),silicon photomultiplier(SiPM),avalanche photodiode(APD),and photodiode(PD).The temperature stability,long-term stability,repeatability,signal-to-noise ratio(SNR),and current dose response of the PSFD with the abovementioned photoelectric devices were studied using a pulsed LED light source and the Small Animal Radiation Therapy platform.An exponential relationship between the dark/ne current and temperature was obtained for all the devices.I is shown that the APD is the most sensitive device to temperature,with a current dependence on temperature reaching 6.5%C^(-1)at room temperature,whereas for the other devices this dependence is always<0:6%C^(-1).In terms of long-term stability,the net current of PD can change by up to 4%when working continuously for 8 h and 2%when working intermittently for 32 h,whereas for the other devices,the changes are all<1%.For the dose response,the PMT and SiPM exhibit excellent linear responses and SNRs within the range of 0.1-60 Gy/min For the PSFD with a current readout mode,the performance of the PMT and SiPM is concluded to be better than that of the other devices in the study.In particular,the SiPM,which has a compact size,low bias voltage,and antimagnetic interference,has great advantages for further applications.

Comparison of Different Methods of Multislice Spiral Computed Tomography for the Preoperative Gastric Cancer Staging

Background: To evaluate the diagnostic possibilities of multislice spiral computed tomography (MSCT) in preoperative gastric cancer staging. Methods: A total of 108 patients who had radical gastric cancer surgery were evaluated with MSCT two weeks before surgery in two different stomach imaging methods (water or urographin aqueous solution). Tumor staging was evaluated using the Tumor-Node-Metastasis (TNM) staging. The results from the imaging modalities were compared with the postoperative histopathological outcomes. Results: CT scanning with stomach contrast agent is more accurate (p < 0.05) and specific (p = 0.001) in determining stage T2;however hydrodynamic method is more sensitive (p < 0.005) and has higher PPV (p < 0.005). For stage T3, there was no significant difference between accuracy, positive and negative prognostic values;scanning with stomach contrast was more sensitive (p = 0.016), and hydrodynamic method was more specific (p = 0.026). For stage T4, hydrodynamic method was more sensitive (p = 0.028), but there was no significant difference between accuracy, specificity, positive and negative prognostic values. Conclusions: According to our study results, CT scanning with contrast agent is more accurate and specific in preoperative determination of gastric cancer T2 stage;however hydrodynamic method is more sensitive in preoperative T3 stage determination. We find no significant difference between positive and negative prognostic values of these methods. Scanning with contrast agent was more sensitive, and hydrodynamic method was more specific. Hydrodynamic method is more sensitive in determining gastric cancer T4 stage. CT scan is informative in preoperative gastric cancer M staging;however it is not informative enough for preoperative N staging.

Production of high-energy neutron beam from deuteron breakup

The deuteron breakup on heavy targets has been investigated in the framework of an improved quantum molecular dynamics model,focusing on the production of neutrons near zero degrees.The experimental differential cross sections of neutron production in the 102 MeV d+C reactions were reproduced by simulations.Based on the consistency between the model prediction and experiment,the feasibility of producing a neutron beam through the breakup of deuteron on a carbon target was demonstrated.Because of the nucleon Fermi motion inside the deuteron,the energy spectrum of the inclusive neutron near 0°in the laboratory exhibits considerable energy broadening in the main peak,whereas the long tail on the low-energy side is suppressed.By coincidentally measuring the accompanying deuteron breakup proton,the energy of the neutron can be tagged with an intrinsic uncertainty of approximately 5%(1σ).The tagging efficiency of the accompanying proton on the forward-emitted neutron can reach 90%,which ensures that the differential cross section in the(d,np)channel remains two orders higher than that in(p,n)after considering the measurement of accompanying protons.This enables the application of a well-defined energy neutron beam in an event-by-event scheme.

Cardiac PET/CT and Prognosis

Positron emission tomography(PET)is a powerful noninvasive imaging tool for phenotyping patients at risk of or with known coronary artery disease(CAD).One of the key advantages over other imaging modalities is its unique ability to quantify physiologic processes,including myocardial blood fl ow(in milliliters per minute per gram of myocardium),metabolism,and cardiac receptors,and its high sensitivity for delineating and quantifying molecular targets in vivo using targeted imaging probes.Cardiac PET/CT offers opportunity for a comprehensive noninvasive evaluation of the consequences of atherosclerosis in the coronary arteries and the myocardium.

Oral microbiota and host innate immune response in bisphosphonate-related osteonecrosis of the jaw

Bacterial biofilms have emerged as potential critical triggers in the pathogenesis of bisphosphonate（BP）-related osteonecrosis of the jaw（ONJ） or BRONJ. BRONJ lesions have shown to be heavily colonized by oral bacteria, most of these difficult to cultivate and presents many clinical challenges. The purpose of this study was to characterize the bacterial diversity in BRONJ lesions and to determine host immune response. We examined tissue specimens from three cohorts（n530）; patients with periodontal disease without a history of BP therapy（Control, n510）, patients with periodontal disease having history of BP therapy but without ONJ（BP, n55） and patients with BRONJ（BRONJ, n515）. Denaturing gradient gel electrophoresis of polymerase chain reaction（PCR）-amplified 16 S r RNA gene fragments revealed less bacterial diversity in BRONJ than BP and Control cohorts. Sequence analysis detected six phyla with predominant affiliation to Firmicutes in BRONJ（71.6%）, BP（70.3%） and Control（59.1%）. Significant differences（P,0.05） in genera were observed, between Control/BP, Control/BRONJ and BP/BRONJ cohorts. Enzyme-linked immunosorbent assay（ELISA）results indicated that the levels of myeloperoxidase were significantly lower, whereas interleukin-6 and tumor necrosis factor-alpha levels were moderately elevated in BRONJ patients as compared to Controls. PCR array showed significant changes in BRONJ patients with downregulation of host genes, such as nucleotide-binding oligomerization domain containing protein 2, and cathepsin G, the key modulators for antibacterial response and upregulation of secretory leukocyte protease inhibitor, proteinase 3 and conserved helix–loop–helix ubiquitous kinase. The results suggest that colonization of unique bacterial communities coupled with deficient innate immune response is likely to impact the pathogenesis of ONJ.

RADIOACTIVITY LEVEL OF RESIDENTIAL AREAS AROUND XINJIANG NUCLEAR TESTING SITE AND ESTIMATED POPULATION DOSE

Results are reported on a research for the radioactive level in the investigation region and the control region around the Xinjiang Nuclear Testing Site from 1982 to 1987. There are no significant differences on the land γ radiation level, nor in the radioactive level in the soil, food and water between the two regions. The distribution and transfer of 90Sr, 137Cs and Pu in various kinds of soil are also discussed. It is estimated that the effective dose equivalent of radiation, undergone by the residents around the Testing Site is only 2.9% of that of natural radiation taken yearly by people in normal areas.

MEASUREMENT OF AMPLITUDE AND DELAY OF STIMULUS FREQUENCY OTOACOUSTIC EMISSIONS

Although stimulus frequency otoacoustic emissions (SFOAEs) have been used as a non-invasive measure of cochlear mechanics, clinical and experimental application of SFOAEs has been limited by difficulties in accurately deriving quantitative information from sound pressure measured in the ear canal. In this study, a novel signal processing method for multicomponent analysis (MCA) was used to measure the amplitude and delay of the SFOAE. This report shows the delay-frequency distribution of the SFOAE measured from the human ear. A low level acoustical suppressor near the probe tone significantly suppressed the SFOAE, strongly indicating that the SFOAE was generated at characteristic frequency locations. Information derived from this method may reveal more details of cochlear mechanics in the human ear.

Oral mucosal lipids are antibacterial against Porphyromonas gingivalis, induce ultrastructural damage, and alter bacterial lipid and protein compositions

Oral mucosal and salivary lipids exhibit potent antimicrobial activity for a variety of Gram-positive and Gram-negative bacteria;however,little is known about their spectrum of antimicrobial activity or mechanisms of action against oral bacteria.In this study,we examine the activity of two fatty acids and three sphingoid bases against Porphyromonas gingivalis,an important colonizer of the oral cavity implicated in periodontitis.Minimal inhibitory concentrations,minimal bactericidal concentrations,and kill kinetics revealed variable,but potent,activity of oral mucosal and salivary lipids against P.gingivalis,indicating that lipid structure may be an important determinant in lipid mechanisms of activity against bacteria,although specific components of bacterial membranes are also likely important.Electron micrographs showed ultrastructural damage induced by sapienic acid and phytosphingosine and confirmed disruption of the bacterial plasma membrane.This information,coupled with the association of treatment lipids with P.gingivalis lipids revealed via thin layer chromatography,suggests that the plasma membrane is a likely target of lipid antibacterial activity.Utilizing a combination of two-dimensional in-gel electrophoresis and Western blot followed by mass spectroscopy and N-terminus degradation sequencing we also show that treatment with sapienic acid induces upregulation of a set of proteins comprising a unique P.gingivalis stress response,including proteins important in fatty acid biosynthesis,metabolism and energy production,protein processing,cell adhesion and virulence.Prophylactic or therapeutic lipid treatments may be beneficial for intervention of infection by supplementing the natural immune function of endogenous lipids on mucosal surfaces.

COVID-19 or non-COVID viral pneumonia:How to differentiate based on the radiologic findings?

Influenza viruses were responsible for most adult viral pneumonia.Presently,coronavirus disease 2019(COVID-19)has evolved into serious global pandemic.COVID-19 outbreak is expected to persist in months to come that will be synchronous with the influenza season.The management,prognosis,and protection for these two viral pneumonias differ considerably and differentiating between them has a high impact on the patient outcome.Reverse transcriptase polymerase chain reaction is highly specific but has suboptimal sensitivity.Chest computed tomography(CT)has a high sensitivity for detection of pulmonary disease manifestations and can play a key-role in diagnosing COVID-19.We reviewed 47 studies and delineated CT findings of COVID-19 and influenza pneumonia.The differences observed in the chest CT scan can be helpful in differentiation.For instance,ground glass opacities(GGOs),as the most frequent imaging finding in both diseases,can differ in the pattern of distribution.Peripheral and posterior distribution,multilobular distribution,pure or clear margin GGOs were more commonly reported in COVID-19,whereas central or peri-bronchovascular GGOs and pure consolidations were more seen in influenza A(H1N1).In review of other imaging findings,further differences were noticed.Subpleural curvilinear lines,sugar melted sign,intra-lesional vascular enlargement,reverse halo sign,and fibrotic bands were more reported in COVID-19 than H1N1,while air space nodule,tree-in-bud,bronchiectasia,pleural effusion,and cavitation were more seen in H1N1.This delineation,when combined with clinical manifestations and laboratory results may help to differentiate these two viral infections.

Fluorescent Nile blue-functionalized poly(N-isopropylacrylamide)microgels responsive to temperature and polyamines

Fluorescent poly(N-isopropylacrylamide-co-Nile blue)(pNIPAm-co-NB)microgels were synthesized that exhibited fluorescence intensity changes in a water temperature-dependent fashion.NB is well known to exhibit fluorescence intensity that depends on the hydrophobicity of the environment,while pNIPAm-based microgels are well known to transition from swollen(hydrophilic)to collapsed(relatively hydrophobic)at temperatures greater than 32℃;hence,we attribute the above behavior to the hydrophobicity changes of the microgels with increasing temperature.This phenomenon is ultimately due to NB dimers(relatively quenched fluorescence)being broken in the hydrophobic environment of the microgels leading to relatively enhanced fluorescence.We went on to show that the introduction of cucurbit[7]uril(CB[7])into the pNIPAm-co-NB microgels enhanced their fluorescence allowing them to be used for polyamine(e.g.,spermine[SPM])detection.Specifically,CB[7]forms a host–guest interaction with NB in the microgels,which prevents NB dimerization and enhances their fluorescence.When SPM is present,it forms a host–guest complex that is favored over the CB[7]-NB host–guest interaction,which frees the NB for dimerization and leads to fluorescence quenching.As a result,we could generate an SPM sensor capable of SPM detection down to~0.5µmol/L in complicated matrixes such as serum and urine.