Gram negative aerobic bacteria such as Acetic Acid Bacteria, which include Acetobacter and Gluconobacter, have historically caused significant problems to brewers. Although incidences of spoilage have recently reduced...Gram negative aerobic bacteria such as Acetic Acid Bacteria, which include Acetobacter and Gluconobacter, have historically caused significant problems to brewers. Although incidences of spoilage have recently reduced as a result of improvements in beer packaging, these bacteria are still a concern in dispense systems in pub breweries, public houses and cask conditioned beers. Gram negative facultative bacteria of the genus Zymomonas can spoil primed cask conditioned beer and cider. There is a wide range of Enterobacteraeceace which are found within brewery environments and they serve as indicator microorganisms for hygiene and sanitation. Gram negative strictly anaerobic bacteria such as Pectinatus and Megasphaera have recently emerged as a significant threat due to the improvement in reduction of oxygen levels in beer and an increase in production of unpasteurised beer. Pectinatus and Megasphaera are sensitive to routine cleaning agents used in breweries, but they can survive and proliferate in biofilms eventually causing spoilage of beer. This review focuses on Gram negative aerobic, facultative anaerobic and strictly anaerobic brewery related spoilage bacteria.展开更多
<span style="font-family:;" "=""><span style="font-family:Verdana;">Antimicrobial resistance refers to the ability of microorganisms to grow in the presence of an antimic...<span style="font-family:;" "=""><span style="font-family:Verdana;">Antimicrobial resistance refers to the ability of microorganisms to grow in the presence of an antimicrobial agent at a concentration that will normally kill or inhibit their growth. Antimicrobial resistance has become a major global threat making treatment of infections tougher especially with high cost of treatment in humans and animals. This study was done to determine the Multiple Antibiotic Resistant Index (MARI) of Gram-negative bacteria from bird droppings in two commercial poultries in Enugu. Forty (40) samples were collected from each of the poultries. Isolates were identified by standard microbiological methods. The isolates identified were </span><i><span style="font-family:Verdana;">Escherichia</span></i> <i><span style="font-family:Verdana;">coli</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Klebsiella</span></i> <i><span style="font-family:Verdana;">pneumoniae</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Pseudomonas</span></i> <i><span style="font-family:Verdana;">aeruginosa</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Citrobacter</span></i><span style="font-family:Verdana;"> spp, </span><i><span style="font-family:Verdana;">Proteus</span></i><span style="font-family:Verdana;"> spp. and, </span><i><span style="font-family:Verdana;">Enterobacter</span></i><span style="font-family:Verdana;"> spp. Antibiotic susceptibility testing was carried out using disc diffusion technique. The organisms were tested against pefloxacin, augmentin (amoxicillin and clavulanic acid), ceftazidime, streptomycin, ciprofloxacin, gentamycin, cephalothin, neomycin and ofloxacin. The result of the susceptibility test showed that </span><i><span style="font-family:Verdana;">Proteus</span></i><span style="font-family:Verdana;"> spp had the highest resistance and MARI value of 0.5 and</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">1.0 respectively. The other MARI values were </span><i><span style="font-family:Verdana;">Escherichia</span></i> <i><span style="font-family:Verdana;">coli</span></i><span style="font-family:Verdana;"> (0.9), </span><i><span style="font-family:Verdana;">Klebsiella</span></i> <i><span style="font-family:Verdana;">pneumonia</span></i><span style="font-family:Verdana;"> (0.9), </span><i><span style="font-family:Verdana;">Pseudomonas</span></i> <i><span style="font-family:Verdana;">aeruginosa</span></i><span style="font-family:Verdana;"> (0.8), </span><i><span style="font-family:Verdana;">Citrobacter</span></i><span style="font-family:Verdana;"> spp (0.8) and </span><i><span style="font-family:Verdana;">Enterobacter</span></i><span style="font-family:Verdana;"> spp (0.7). These results suggest that bacterial organisms from poultry source can contribute significantly to the spread of multi-antibiotic resistant organisms. This could arise from the indiscriminate use of antibiotics in bird feeds in poultries.</span></span>展开更多
BACKGROUND Pylephlebitis is an extremely rare form of septic thrombophlebitis involving the portal vein,carrying high rates of morbidity and mortality.CASE SUMMARY We present a case of a 42-year-old male with no past ...BACKGROUND Pylephlebitis is an extremely rare form of septic thrombophlebitis involving the portal vein,carrying high rates of morbidity and mortality.CASE SUMMARY We present a case of a 42-year-old male with no past medical history who presented with acute onset of abdominal pain and altered mental status with laboratory tests demonstrating new-onset acute liver failure.Pylephlebitis was determined to be the underlying etiology due to subsequent workup revealing polymicrobial gram-negative anaerobic bacteremia and complete thrombosis of the main and left portal veins.To our knowledge,this is the first documented case of acute liver failure as a potential life-threatening complication of pylephlebitis.CONCLUSION Our case highlights the importance of considering pylephlebitis in the broad differential for abdominal pain,especially if there are co-existing risk factors for hypercoagulability.We also demonstrate that fulminant hepatic failure in these patients can potentially be reversible with the immediate initiation of antibiotics and anticoagulation.展开更多
AIM: To analyze 67 cases of splenic abscess in a medica center of Taiwan during a period of 19 years. METHODS: From January 1986 to December 2004, a total of 67 patients with splenic abscess were enrolled for the re...AIM: To analyze 67 cases of splenic abscess in a medica center of Taiwan during a period of 19 years. METHODS: From January 1986 to December 2004, a total of 67 patients with splenic abscess were enrolled for the retrospective study. The clinical characteristics, underlying diseases, organism spectra, therapeutic methods, APACHE Ⅱ scores, and mortality rates were analyzed. RESULTS: There were 41 males and 26 females with the mean age of 54.14-14.1 years. Multiple splenic abscesses (MSA) account for 28.4% and solitary splenic abscess in 71.6% of the patients. Twenty-six of sixtyseven patients (35.8%) had extrasplenic abscesses, with leading site of liver (34.6%), Microbiological cultures were positive in 58 patients (86.6%), with 71.8% in blood culture and 93.5% in abscess culture. Gram negative bacillus (GNB) infection predominated (55.2%), with leading pathogen of Klebslella pneumoniae (22.4%), followed by gram positive coccus (GPC) infection (31%). Splenectomy was performed in 26 patients (38.8%), percutaneous drainage or aspiration in 21 (31.3%), and antibiotic therapy alone in 20 patients (29.9%). Eventually, 12 of 67 patients expired (17.9 %). By statistics, spleen infected with GNB was likely to develop multiple abscesses compared with infection with GPC (P=0.036). Patients with GNB infection (P=0.009) and multiple abscesses (P=0.011) experienced a higher mortality rate than patients with GPC infection and solitary abscess. The mean APACHE Ⅱ score of 12 ex- pired patients (16.3±3.2) was significantly higher than that of the 55 survivals (7.2 ± 3.8) (P〈 0.001). CONCLUSION: MSA, GNB infection, and high APACHE Ⅱ scores are poor prognostic factors. Early surgical intervention should be encouraged when these risk factors are present.展开更多
Photodynamic inactivation of microorganisms known as antibacterial photodynamic therapy(APDT)is one of the most promising and innovative approaches for the destruction of pathogenic microorganisms.Among the photosensi...Photodynamic inactivation of microorganisms known as antibacterial photodynamic therapy(APDT)is one of the most promising and innovative approaches for the destruction of pathogenic microorganisms.Among the photosensitizers(PSs),compounds based on cationic porphyrins/metalloporphyrins are most successfully used to inactivate microorganisms.Series of meso-substituted cationic pyridylporphyrins and metalloporphyrins with various peripheral groups in the third and fourth positions of the pyrrole ring have been synthesized in Armenia.The aim of this work was to determine and test the most e®ective cationic porphyrins and metalloporphyrins with high photoactivity against Gram negative and Gram positive microorganisms.It was shown that the synthesized cationic pyridylporphyrins/metalloporphyrins exhibit a high degree of phototoxicity towards both types of bacteria,including the methicillinresistant S.aureus strain.Zinc complexes of porphyrins are more phototoxic than metal-free porphyrin analogs.The e®ectiveness of these Zn–metalloporphyrins on bacteria is consistent with the level of singlet oxygen generation.It was found that the high antibacterial activity of the studied cationic porphyrins/metalloporphyrins depends on four factors:the presence in the porphyrin macrocycle of a positive charge(+4),a central metal atom(Zn2þÞand hydrophobic peripheral functional groups as well as high values of quantum yields of singlet oxygen.The results indicate that meso-substituted cationic pyridylporphyrins/metalloporphyrins cannd wider application in photoinactivation of bacteria than anionic or neutral PSs usually used in APDT.展开更多
The prevalence of multi drug resistant gram-negative bacteria to commonly first line drugs in blood is a serious problem in Equatorial Guinea and other world. This is the first study describing antibiotic resistance a...The prevalence of multi drug resistant gram-negative bacteria to commonly first line drugs in blood is a serious problem in Equatorial Guinea and other world. This is the first study describing antibiotic resistance analysis of blood stream infection in Equatorial Guinea. Our study presents alarming rate of inefficiency of the most commonly prescribed drugs to treatment Klebsiella pneumoniae, Escherichia coli and Acinetobacter species isolates as the most frequency etiologic agents in blood stream infection. Out of 1849 blood culture the bacterial etiological agents were isolated from 196 (10.6%) samples. E. coli (n = 22), K. pneumonia (n = 39) and Acinetobacter (n = 17) represent 71.6% of all gram negative bacterial isolates. Almost all isolates of K. pneumonia and Acinetobacter sp. (92.1% and 100%, respectively) and about 50% of E. coli strains possessed extended-spectrum β-lactamase activity. Alarming level of multi drug resistant gram negative strains was observed. E. coli and K. pneumonia and Acinetobacter isolates demonstrated low sensitivity to all commonly prescribed drugs such as Ampicillin, Trimethoprim/Sulfamethoxazole, Doxycycline, Gentamycin Amoxicicline/Clavulanic Acid, Cefuroxime, Ciprofloxacine. It is especially worth noting the low efficiency of third generation cephalosporins (Cefrtiaxon) against Acinetobacter and Klebsiella with their resistance rate of 94.7% and 100% respectively. Moreover, the alarming level of low sensitivity to Piperacilin/Tazobactam of K. pneumonia (22%) and Acinetobacter (29.4%) was been found. The 17.6% of Acinetobacter isolated was carbomenem resistant. Just Imipenem and Amikacin were the most sensitive drug against these bacterial strains.展开更多
In this study atmospheric pressure dielectric barrier discharge (DBD) plasma has been employed for sterilizing dry turmeric powders. A 6 kV, 6 kHz frequency generator was used to generate plasma with Ar, Ar/Ou, He, ...In this study atmospheric pressure dielectric barrier discharge (DBD) plasma has been employed for sterilizing dry turmeric powders. A 6 kV, 6 kHz frequency generator was used to generate plasma with Ar, Ar/Ou, He, and He/O2 gases between the 5 mm gap of two quartz covered electrodes. The complete sterilization time of samples due to plasma treatment was measured. The most important contaminant of turmeric is bacillus subtilis. The results show that the shortest sterilization time of 15 rain is achieved by exposing the samples to Ar/O2 plasma. Survival curves of samples are exponential functions of time and the addition of oxygen to plasma leads to a significant increase of the absolute value of time constant of the curves. Magnitudes of protein and DNA in treated samples were increased to a similar value for all samples. Taste, color, and solubility of samples were not changed after the plasma treatment.展开更多
Introduction:Pakistan Biological Safety Association(PBSA)is a not for profit,nongovernmental,professional organization established in 2008 and is striving to promote and implement Bio risk management in Pakistan.PBSA ...Introduction:Pakistan Biological Safety Association(PBSA)is a not for profit,nongovernmental,professional organization established in 2008 and is striving to promote and implement Bio risk management in Pakistan.PBSA accelerated its program for strategic training of the national life scientists from 2013 and is still working on that mandate with the help of Fogarty International Center(FIC)&National Institute of Health USA and other international organizations working on this Global Health Security Initiative and subsequently Agenda(GHSA)Aims&Objectives:This biosafety training program was developed for capacity building of M.Phil.and PhD graduates the future laboratory users of Basic Medical Sciences Institute(BMSI),Jinnah Post Graduate Medical Center which is the largest tertiary care hospital in Karachi,Pakistan involved in Research&Development(R&D)in medical sciences.Materials&Methods:This Pre post study was carried at Basic Medical Sciences Institute(JPMC),during the period of October 2018 to January 2019.A total of 48(16 PhD.32 M.Phil.)Grads students participated in the following study.The training program is administered through,custom made 4-month course having 16 contact hours also 4 hours of practical training.Training was evaluated using written assessment.The pre and post-training test was conducted after each session.Each test comprised of 15 multiple choice questions(MCQs)pre and post session making it 30 MCQs in total for each session.A final assessment consisting 30 MCQs conducted at the end of course.Results:There was vast difference observed in the post assessment results as compared to the pre assessment results.At the end of the course final assessment was carried out which gave an overall impression of vast change(83.3%)in awareness regarding bio risk management among the graduate students,which reflected the efficacy of this training.To ensure the validity of results and the intention to improvise the quality of course in future,feedback regarding the course and trainer was obtain through Likert scale.Reliability of Likert scale carried through Cronbach’s alpha,showed all variables with a maximum score of 0.9,indicating high reliability of the generated feedback evaluation.Conclusion:This study highlighted that through concerted efforts of professional organizations,proper awareness of public and concerned personals,regarding Biosafety&Biosecurity can certainly reduce the chances of errors and will ensure potential safety and security to the laboratory workers,community and environment,potentially exposed to these pathogens&toxins which are regarded as biohazards.展开更多
The objective of this study was to realize the degree of biosafety precautions and measures recorded among different Private Hospitals and Diagnostic labs personnel situated in different areas of Karachi,Pakistan.One ...The objective of this study was to realize the degree of biosafety precautions and measures recorded among different Private Hospitals and Diagnostic labs personnel situated in different areas of Karachi,Pakistan.One thirty two private hospital based laboratory technicians were selected from all 12 selected areas in Karachi.The laboratory technicians were interviewed then a survey form was completed by the interviewer.The survey was conducted in 3 months duration from May 2017 to July 2017.The total number of members in this study was 132,of which 85 were males and 47 were females.Results presented that 65%of the laboratory technicians did not use any type of PPE and 35%of the respondents recapped used syringes frequently while 25%recapped occasionally.For avoiding the reuse of syringes,Pakistani governments recommend that they be cut before discarding;however,only 65%of the respondents followed the given procedure.Even though mouth pipetting is considered outdated,45%of the technicians continue to do so for numerous purposes.Results of this survey established an absence of awareness about good and proper lab practices and lab biosafety measures among lab technicians in Karachi,Pakistan.展开更多
Silver nanoparticles in the range of 10-40 nm were synthesized chemically and by laser ablation, em- ployed for in vitro antibacterial action against human pathogenic bacterium. Their formation was evidenced by UV-vis...Silver nanoparticles in the range of 10-40 nm were synthesized chemically and by laser ablation, em- ployed for in vitro antibacterial action against human pathogenic bacterium. Their formation was evidenced by UV-visible spectrophotometer; particle size confirmed by atomic force microscopy, crystal structure determined by X-ray diffraction and chemical composition investigated by Fourier transform infrared spec- troscopy. The calculated MIC (minimum inhibitory concentration) of chemically synthesized nanoparticles with 30-40 nm in size are 2.8 μg/mL 4.37 μg/mL 13.5μg/mL and 2.81 p.g/mL for E. coil, S. aureus, B. subtillis and Salmonella, respectively. Whereas laser ablated nanoparticles exhibit MIC of 2.10 μg/mL 2.36 μg/ mL and 2.68 μg/mL for E. coli, S. aureus and Salmonella, respectively.展开更多
Over the past 20 years,and with greater urgency since the H5N1 papers controversy(2012),dual-use research of concern(DURC)has been extensively debated by the scientific community,regulators,and the public at large.Man...Over the past 20 years,and with greater urgency since the H5N1 papers controversy(2012),dual-use research of concern(DURC)has been extensively debated by the scientific community,regulators,and the public at large.Many have raised the need to regulate DURC;however,despite the urgency of this issue,to date,only two countries have implemented specific regulations,United States and Israel(notably,China is in the final stages of creating a set of DURC-related regulations).In this paper,I have compared these policies as case studies that may benefit other countries.Therefore,the present study aimed to critically compare the DURC policies of the US and Israel and determine whether their different approaches provide a rigorous framework for the regulation of DURC.I have shown that in some aspects,they have adopted similar approaches;for example,allowing local committees to play a role in assessing the research.However,they differ in certain important aspects;for instance,the US policies have laid out a mechanism through which academic institutions and the government decide jointly on how to address risky studies,while the Israeli law places the authority solely in government hands.My aim in comparing the policies is twofold;first,to reveal the weaknesses and strengths of each policy,thereby aiding their improvement,and second,to provide those that are considering developing policies in this field an overview of what the current approaches look like,thereby enabling them to articulate their own approach while taking into account the experience gained by the US and Israel.展开更多
The United Nations Secretary-General’s Mechanism(UNSGM)for investigating the alleged use of biological weapons was proposed in early 2013,with support from the World Organization for Animal Health(OIE)and World Healt...The United Nations Secretary-General’s Mechanism(UNSGM)for investigating the alleged use of biological weapons was proposed in early 2013,with support from the World Organization for Animal Health(OIE)and World Health Organization(WHO).1 The UNSGM and related documents call for designated laboratories to support an investigation of the alleged use of biological weapons.Designed laboratories participating in the UNSGM investigations must not report false results,positive or negative.It is not affordable for whatever reason.展开更多
文摘Gram negative aerobic bacteria such as Acetic Acid Bacteria, which include Acetobacter and Gluconobacter, have historically caused significant problems to brewers. Although incidences of spoilage have recently reduced as a result of improvements in beer packaging, these bacteria are still a concern in dispense systems in pub breweries, public houses and cask conditioned beers. Gram negative facultative bacteria of the genus Zymomonas can spoil primed cask conditioned beer and cider. There is a wide range of Enterobacteraeceace which are found within brewery environments and they serve as indicator microorganisms for hygiene and sanitation. Gram negative strictly anaerobic bacteria such as Pectinatus and Megasphaera have recently emerged as a significant threat due to the improvement in reduction of oxygen levels in beer and an increase in production of unpasteurised beer. Pectinatus and Megasphaera are sensitive to routine cleaning agents used in breweries, but they can survive and proliferate in biofilms eventually causing spoilage of beer. This review focuses on Gram negative aerobic, facultative anaerobic and strictly anaerobic brewery related spoilage bacteria.
文摘<span style="font-family:;" "=""><span style="font-family:Verdana;">Antimicrobial resistance refers to the ability of microorganisms to grow in the presence of an antimicrobial agent at a concentration that will normally kill or inhibit their growth. Antimicrobial resistance has become a major global threat making treatment of infections tougher especially with high cost of treatment in humans and animals. This study was done to determine the Multiple Antibiotic Resistant Index (MARI) of Gram-negative bacteria from bird droppings in two commercial poultries in Enugu. Forty (40) samples were collected from each of the poultries. Isolates were identified by standard microbiological methods. The isolates identified were </span><i><span style="font-family:Verdana;">Escherichia</span></i> <i><span style="font-family:Verdana;">coli</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Klebsiella</span></i> <i><span style="font-family:Verdana;">pneumoniae</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Pseudomonas</span></i> <i><span style="font-family:Verdana;">aeruginosa</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Citrobacter</span></i><span style="font-family:Verdana;"> spp, </span><i><span style="font-family:Verdana;">Proteus</span></i><span style="font-family:Verdana;"> spp. and, </span><i><span style="font-family:Verdana;">Enterobacter</span></i><span style="font-family:Verdana;"> spp. Antibiotic susceptibility testing was carried out using disc diffusion technique. The organisms were tested against pefloxacin, augmentin (amoxicillin and clavulanic acid), ceftazidime, streptomycin, ciprofloxacin, gentamycin, cephalothin, neomycin and ofloxacin. The result of the susceptibility test showed that </span><i><span style="font-family:Verdana;">Proteus</span></i><span style="font-family:Verdana;"> spp had the highest resistance and MARI value of 0.5 and</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">1.0 respectively. The other MARI values were </span><i><span style="font-family:Verdana;">Escherichia</span></i> <i><span style="font-family:Verdana;">coli</span></i><span style="font-family:Verdana;"> (0.9), </span><i><span style="font-family:Verdana;">Klebsiella</span></i> <i><span style="font-family:Verdana;">pneumonia</span></i><span style="font-family:Verdana;"> (0.9), </span><i><span style="font-family:Verdana;">Pseudomonas</span></i> <i><span style="font-family:Verdana;">aeruginosa</span></i><span style="font-family:Verdana;"> (0.8), </span><i><span style="font-family:Verdana;">Citrobacter</span></i><span style="font-family:Verdana;"> spp (0.8) and </span><i><span style="font-family:Verdana;">Enterobacter</span></i><span style="font-family:Verdana;"> spp (0.7). These results suggest that bacterial organisms from poultry source can contribute significantly to the spread of multi-antibiotic resistant organisms. This could arise from the indiscriminate use of antibiotics in bird feeds in poultries.</span></span>
文摘BACKGROUND Pylephlebitis is an extremely rare form of septic thrombophlebitis involving the portal vein,carrying high rates of morbidity and mortality.CASE SUMMARY We present a case of a 42-year-old male with no past medical history who presented with acute onset of abdominal pain and altered mental status with laboratory tests demonstrating new-onset acute liver failure.Pylephlebitis was determined to be the underlying etiology due to subsequent workup revealing polymicrobial gram-negative anaerobic bacteremia and complete thrombosis of the main and left portal veins.To our knowledge,this is the first documented case of acute liver failure as a potential life-threatening complication of pylephlebitis.CONCLUSION Our case highlights the importance of considering pylephlebitis in the broad differential for abdominal pain,especially if there are co-existing risk factors for hypercoagulability.We also demonstrate that fulminant hepatic failure in these patients can potentially be reversible with the immediate initiation of antibiotics and anticoagulation.
文摘AIM: To analyze 67 cases of splenic abscess in a medica center of Taiwan during a period of 19 years. METHODS: From January 1986 to December 2004, a total of 67 patients with splenic abscess were enrolled for the retrospective study. The clinical characteristics, underlying diseases, organism spectra, therapeutic methods, APACHE Ⅱ scores, and mortality rates were analyzed. RESULTS: There were 41 males and 26 females with the mean age of 54.14-14.1 years. Multiple splenic abscesses (MSA) account for 28.4% and solitary splenic abscess in 71.6% of the patients. Twenty-six of sixtyseven patients (35.8%) had extrasplenic abscesses, with leading site of liver (34.6%), Microbiological cultures were positive in 58 patients (86.6%), with 71.8% in blood culture and 93.5% in abscess culture. Gram negative bacillus (GNB) infection predominated (55.2%), with leading pathogen of Klebslella pneumoniae (22.4%), followed by gram positive coccus (GPC) infection (31%). Splenectomy was performed in 26 patients (38.8%), percutaneous drainage or aspiration in 21 (31.3%), and antibiotic therapy alone in 20 patients (29.9%). Eventually, 12 of 67 patients expired (17.9 %). By statistics, spleen infected with GNB was likely to develop multiple abscesses compared with infection with GPC (P=0.036). Patients with GNB infection (P=0.009) and multiple abscesses (P=0.011) experienced a higher mortality rate than patients with GPC infection and solitary abscess. The mean APACHE Ⅱ score of 12 ex- pired patients (16.3±3.2) was significantly higher than that of the 55 survivals (7.2 ± 3.8) (P〈 0.001). CONCLUSION: MSA, GNB infection, and high APACHE Ⅱ scores are poor prognostic factors. Early surgical intervention should be encouraged when these risk factors are present.
基金the Decree of the Government of the Russian Federation No.220 of April 9,2010(Agreement No.075-15-2021-615 of June 4,2021).
文摘Photodynamic inactivation of microorganisms known as antibacterial photodynamic therapy(APDT)is one of the most promising and innovative approaches for the destruction of pathogenic microorganisms.Among the photosensitizers(PSs),compounds based on cationic porphyrins/metalloporphyrins are most successfully used to inactivate microorganisms.Series of meso-substituted cationic pyridylporphyrins and metalloporphyrins with various peripheral groups in the third and fourth positions of the pyrrole ring have been synthesized in Armenia.The aim of this work was to determine and test the most e®ective cationic porphyrins and metalloporphyrins with high photoactivity against Gram negative and Gram positive microorganisms.It was shown that the synthesized cationic pyridylporphyrins/metalloporphyrins exhibit a high degree of phototoxicity towards both types of bacteria,including the methicillinresistant S.aureus strain.Zinc complexes of porphyrins are more phototoxic than metal-free porphyrin analogs.The e®ectiveness of these Zn–metalloporphyrins on bacteria is consistent with the level of singlet oxygen generation.It was found that the high antibacterial activity of the studied cationic porphyrins/metalloporphyrins depends on four factors:the presence in the porphyrin macrocycle of a positive charge(+4),a central metal atom(Zn2þÞand hydrophobic peripheral functional groups as well as high values of quantum yields of singlet oxygen.The results indicate that meso-substituted cationic pyridylporphyrins/metalloporphyrins cannd wider application in photoinactivation of bacteria than anionic or neutral PSs usually used in APDT.
文摘The prevalence of multi drug resistant gram-negative bacteria to commonly first line drugs in blood is a serious problem in Equatorial Guinea and other world. This is the first study describing antibiotic resistance analysis of blood stream infection in Equatorial Guinea. Our study presents alarming rate of inefficiency of the most commonly prescribed drugs to treatment Klebsiella pneumoniae, Escherichia coli and Acinetobacter species isolates as the most frequency etiologic agents in blood stream infection. Out of 1849 blood culture the bacterial etiological agents were isolated from 196 (10.6%) samples. E. coli (n = 22), K. pneumonia (n = 39) and Acinetobacter (n = 17) represent 71.6% of all gram negative bacterial isolates. Almost all isolates of K. pneumonia and Acinetobacter sp. (92.1% and 100%, respectively) and about 50% of E. coli strains possessed extended-spectrum β-lactamase activity. Alarming level of multi drug resistant gram negative strains was observed. E. coli and K. pneumonia and Acinetobacter isolates demonstrated low sensitivity to all commonly prescribed drugs such as Ampicillin, Trimethoprim/Sulfamethoxazole, Doxycycline, Gentamycin Amoxicicline/Clavulanic Acid, Cefuroxime, Ciprofloxacine. It is especially worth noting the low efficiency of third generation cephalosporins (Cefrtiaxon) against Acinetobacter and Klebsiella with their resistance rate of 94.7% and 100% respectively. Moreover, the alarming level of low sensitivity to Piperacilin/Tazobactam of K. pneumonia (22%) and Acinetobacter (29.4%) was been found. The 17.6% of Acinetobacter isolated was carbomenem resistant. Just Imipenem and Amikacin were the most sensitive drug against these bacterial strains.
文摘In this study atmospheric pressure dielectric barrier discharge (DBD) plasma has been employed for sterilizing dry turmeric powders. A 6 kV, 6 kHz frequency generator was used to generate plasma with Ar, Ar/Ou, He, and He/O2 gases between the 5 mm gap of two quartz covered electrodes. The complete sterilization time of samples due to plasma treatment was measured. The most important contaminant of turmeric is bacillus subtilis. The results show that the shortest sterilization time of 15 rain is achieved by exposing the samples to Ar/O2 plasma. Survival curves of samples are exponential functions of time and the addition of oxygen to plasma leads to a significant increase of the absolute value of time constant of the curves. Magnitudes of protein and DNA in treated samples were increased to a similar value for all samples. Taste, color, and solubility of samples were not changed after the plasma treatment.
文摘Introduction:Pakistan Biological Safety Association(PBSA)is a not for profit,nongovernmental,professional organization established in 2008 and is striving to promote and implement Bio risk management in Pakistan.PBSA accelerated its program for strategic training of the national life scientists from 2013 and is still working on that mandate with the help of Fogarty International Center(FIC)&National Institute of Health USA and other international organizations working on this Global Health Security Initiative and subsequently Agenda(GHSA)Aims&Objectives:This biosafety training program was developed for capacity building of M.Phil.and PhD graduates the future laboratory users of Basic Medical Sciences Institute(BMSI),Jinnah Post Graduate Medical Center which is the largest tertiary care hospital in Karachi,Pakistan involved in Research&Development(R&D)in medical sciences.Materials&Methods:This Pre post study was carried at Basic Medical Sciences Institute(JPMC),during the period of October 2018 to January 2019.A total of 48(16 PhD.32 M.Phil.)Grads students participated in the following study.The training program is administered through,custom made 4-month course having 16 contact hours also 4 hours of practical training.Training was evaluated using written assessment.The pre and post-training test was conducted after each session.Each test comprised of 15 multiple choice questions(MCQs)pre and post session making it 30 MCQs in total for each session.A final assessment consisting 30 MCQs conducted at the end of course.Results:There was vast difference observed in the post assessment results as compared to the pre assessment results.At the end of the course final assessment was carried out which gave an overall impression of vast change(83.3%)in awareness regarding bio risk management among the graduate students,which reflected the efficacy of this training.To ensure the validity of results and the intention to improvise the quality of course in future,feedback regarding the course and trainer was obtain through Likert scale.Reliability of Likert scale carried through Cronbach’s alpha,showed all variables with a maximum score of 0.9,indicating high reliability of the generated feedback evaluation.Conclusion:This study highlighted that through concerted efforts of professional organizations,proper awareness of public and concerned personals,regarding Biosafety&Biosecurity can certainly reduce the chances of errors and will ensure potential safety and security to the laboratory workers,community and environment,potentially exposed to these pathogens&toxins which are regarded as biohazards.
文摘The objective of this study was to realize the degree of biosafety precautions and measures recorded among different Private Hospitals and Diagnostic labs personnel situated in different areas of Karachi,Pakistan.One thirty two private hospital based laboratory technicians were selected from all 12 selected areas in Karachi.The laboratory technicians were interviewed then a survey form was completed by the interviewer.The survey was conducted in 3 months duration from May 2017 to July 2017.The total number of members in this study was 132,of which 85 were males and 47 were females.Results presented that 65%of the laboratory technicians did not use any type of PPE and 35%of the respondents recapped used syringes frequently while 25%recapped occasionally.For avoiding the reuse of syringes,Pakistani governments recommend that they be cut before discarding;however,only 65%of the respondents followed the given procedure.Even though mouth pipetting is considered outdated,45%of the technicians continue to do so for numerous purposes.Results of this survey established an absence of awareness about good and proper lab practices and lab biosafety measures among lab technicians in Karachi,Pakistan.
文摘Silver nanoparticles in the range of 10-40 nm were synthesized chemically and by laser ablation, em- ployed for in vitro antibacterial action against human pathogenic bacterium. Their formation was evidenced by UV-visible spectrophotometer; particle size confirmed by atomic force microscopy, crystal structure determined by X-ray diffraction and chemical composition investigated by Fourier transform infrared spec- troscopy. The calculated MIC (minimum inhibitory concentration) of chemically synthesized nanoparticles with 30-40 nm in size are 2.8 μg/mL 4.37 μg/mL 13.5μg/mL and 2.81 p.g/mL for E. coil, S. aureus, B. subtillis and Salmonella, respectively. Whereas laser ablated nanoparticles exhibit MIC of 2.10 μg/mL 2.36 μg/ mL and 2.68 μg/mL for E. coli, S. aureus and Salmonella, respectively.
基金Financial support for this research was provided by The Israeli Ministry of Science,Technology,and Space(Grant no.3-10739).
文摘Over the past 20 years,and with greater urgency since the H5N1 papers controversy(2012),dual-use research of concern(DURC)has been extensively debated by the scientific community,regulators,and the public at large.Many have raised the need to regulate DURC;however,despite the urgency of this issue,to date,only two countries have implemented specific regulations,United States and Israel(notably,China is in the final stages of creating a set of DURC-related regulations).In this paper,I have compared these policies as case studies that may benefit other countries.Therefore,the present study aimed to critically compare the DURC policies of the US and Israel and determine whether their different approaches provide a rigorous framework for the regulation of DURC.I have shown that in some aspects,they have adopted similar approaches;for example,allowing local committees to play a role in assessing the research.However,they differ in certain important aspects;for instance,the US policies have laid out a mechanism through which academic institutions and the government decide jointly on how to address risky studies,while the Israeli law places the authority solely in government hands.My aim in comparing the policies is twofold;first,to reveal the weaknesses and strengths of each policy,thereby aiding their improvement,and second,to provide those that are considering developing policies in this field an overview of what the current approaches look like,thereby enabling them to articulate their own approach while taking into account the experience gained by the US and Israel.
文摘The United Nations Secretary-General’s Mechanism(UNSGM)for investigating the alleged use of biological weapons was proposed in early 2013,with support from the World Organization for Animal Health(OIE)and World Health Organization(WHO).1 The UNSGM and related documents call for designated laboratories to support an investigation of the alleged use of biological weapons.Designed laboratories participating in the UNSGM investigations must not report false results,positive or negative.It is not affordable for whatever reason.