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1.
《Vaccine》2020,38(44):6941-6953
Addressing vaccine management bottlenecks, including high vaccine wastage rates, has traditionally been addressed through health worker training and other didactic methods of technical assistance or support as required. It has been shown, though, that the high level of technical skills, expertise, and responsibility required in vaccine handling and management cannot be achieved by mere didactic learning. While gains have been made in vaccine management and handling with these approaches, there remain challenges of high vaccine wastage rates and poor vaccine management practices across the board. Interestingly, approaching vaccine management through social behavior change has not been documented. Through Participatory Action Research (PAR), which is increasingly being used in health sciences, we explore an attempt at strengthening vaccine management and thus reducing high vaccine wastage rates by working together with health workers to identify plausible, realistic solutions to vaccine management through social behavior change. Select health workers directly involved with the immunization program in the four major provinces of the Solomon Islands were identified purposively to use action media and come up with concepts and materials for social behavior change communication that will have an impact on effective vaccine management and reducing wastages. This is the first documented use of such methodology in addressing vaccine management issues. 相似文献
2.
穴位注射卡介菌多糖核酸治疗支气管哮喘疗效观察 总被引:1,自引:0,他引:1
目的:观察卡介菌多糖核酸不同给药途径对支气管哮喘疗效的差异。方法:将60例支气管哮喘患者随机分为穴位注射组30例和肌肉注射组30例。穴位注射组将卡介菌多糖核酸注射液于双侧肺俞穴处行穴位注射,前15d每日1次,双侧肺俞穴各注射1mL,15d以后隔日注射1次,连续用药3个月;肌肉注射组将卡介菌多糖核酸注射液2mL注射于一侧臀部,给药时间同穴位注射组。比较治疗后两组肺功能及免疫球蛋白情况及停药3个月后两组症状、体征积分及哮喘控制测试(ACT)得分。结果:两组治疗后肺功能、IgE、IgG、症状体征积分、ACT得分均较治疗前改善(P0.01),但穴位注射组的改善作用优于肌肉注射组(P0.01,0.05),停药3个月后穴位注射组症状体征积分、ACT得分仍优于肌肉注射组(P0.01)。结论:穴位注射较肌肉注射卡介菌多糖核酸能更快速、持久控制患者症状、体征,能更显著改善肺功能、降低IgE,是治疗支气管哮喘的有效方案。 相似文献
3.
Meenakshi Bamnia 《Toxin reviews》2015,34(3):119-124
Emetic and diarrheal toxins produced by endospore-forming Bacillus cereus causes a huge loss to dairy industry. Milk is the suitable medium for the growth of B. cereus. The pathogen is of particular concern in the dairy industry because in spite of aggressive cleaning practices performed by the dairy industry, it is impossible to destroy these hydrophobic spores which adhere to the pipelines of the dairy-processing plant and further these spores may also form biofilms in the milk. The reporting rate of illness caused by B. cereus is vague, usually due to the short duration of (<24?h) the diarrheal and emetic syndromes. The study of toxins production by B. cereus isolates is essential to better determine the methods of controlling these toxins in dairy industry. 相似文献
4.
Carolin Lübker Stefan Dove Wei-Jen Tang Ramona J. Bieber Urbauer Jackob Moskovitz Jeffrey L. Urbauer Roland Seifert 《Toxins》2015,7(7):2598-2614
Bacillus anthracis adenylyl cyclase toxin edema factor (EF) is one component of the anthrax toxin and is essential for establishing anthrax disease. EF activation by the eukaryotic Ca2+-sensor calmodulin (CaM) leads to massive cAMP production resulting in edema. cAMP also inhibits the nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase, thus reducing production of reactive oxygen species (ROS) used for host defense in activated neutrophils and thereby facilitating bacterial growth. Methionine (Met) residues in CaM, important for interactions between CaM and its binding partners, can be oxidized by ROS. We investigated the impact of site-specific oxidation of Met in CaM on EF activation using thirteen CaM-mutants (CaM-mut) with Met to leucine (Leu) substitutions. EF activation shows high resistance to oxidative modifications in CaM. An intact structure in the C-terminal region of oxidized CaM is sufficient for major EF activation despite altered secondary structure in the N-terminal region associated with Met oxidation. The secondary structures of CaM-mut were determined and described in previous studies from our group. Thus, excess cAMP production and the associated impairment of host defence may be afforded even under oxidative conditions in activated neutrophils. 相似文献
5.
Chenfang Zhang Lai Chen Helong Si Wei Gao Peng Liu Jinlin Zhang 《Journal of basic microbiology》2020,60(7):649-658
Nicosulfuron is one of the main sulfonylurea herbicides that have been widely used to protect maize crops. A total of 10 nicosulfuron-degrading strains were isolated from the intestine tract of earthworm Eisenia foetida. Among them, Bacillus velezensis CF57 with the highest degradation efficiency was selected and studied in detail. The degradation characteristics of CF57 showed that it was able to effectively degrade nicosulfuron in a wide range of temperature, pH, and a low inoculation amount, and the response surface analysis revealed that the optimum degradation conditions were 30.8 °C, pH 6.31, and inoculation amount 3.04%. Meanwhile, CF57 could degrade high-concentration nicosulfuron efficiently and posed a broad degradation spectrum of other sulfonylurea herbicides. Furthermore, the localization of degradation enzyme indicated that the nicosulfuron-degrading enzyme was an extracellular fraction. By analyzing the metabolites of nicosulfuron, it could be further determined that the degradation of nicosulfuron by strain CF57 was mainly through the extracellular enzyme, and its possible degradation pathway was mainly derived from the cleavage of the C–N bond of the sulfonylurea bridge. These results may provide new insights into bioremediation of nicosulfuron-contaminated environments and enrich the resources of degrading bacteria of sulfonylurea herbicides. 相似文献
6.
《Vaccine》2022,40(11):1594-1605
In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes. 相似文献
7.
Pectinases are a group of enzymes, which catalyze the breakdown of pectin with numerous applications in various industries. Microbes are the predominant pectinase producers. In the present study, bacterial species were isolated from the soil of a vegetable and fruit dump yard area in a market. The species screened and isolated were identified as Bacillus tequilensis SALBT, and the media and culture conditions were optimized for enhanced production of total pectinases. Maximum pectinolytic activity was observed with 1.5% (w/v) pectin concentration with a combination of yeast extract as nitrogen source and MgSO4 as a metal ion source. Carbon/nitrogen in 2:1 ratio (w/v) yielded the maximum pectinase production with pH and temperature of the medium of 7.5°C and 40°C, respectively. Pectinase activity was determined by the dinitrosalicylic acid method. The pectinase production was relatively stable in the presence of various surfactants like Tween (20, 40, 60, and 80) and sodium dodecyl sulfate (SDS), whereas Triton X‐100 showed an inhibitory effect. Mass production of the enzyme in optimized media and partial purification was performed by ammonium sulfate precipitation followed by dialysis. The approximate molecular weight of the partially purified pectinase was found to be 35 kDa by SDS‐polyacrylamide gel electrophoresis. Application studies such as demucilaging coffee beans and juice clarification were also performed. The findings revealed that B. tequilensis SALBT with pectinase activity has the ability to remove the mucilage layer of pulped coffee seeds, and the partially purified pectinases found to be effective in clarifying juice. 相似文献
8.
Bassem M. Salama Wafaa A. Helmy Tamer I. M. Ragab Mamdouh M. Ali Hanan A. A. Taie Mona A. Esawy 《Journal of basic microbiology》2019,59(10):1004-1015
Screening of 18 bacterial honey isolates revealed that all the isolates were levansucrase producers. The most potent isolate that achieved the highest activity (45.66 U/ml) was identified as Bacillus subtilis NRC based on morphological examination and 16S rRNA. The results recorded the necessity of starch (5 g/L), baker's yeast (12.5 g/L), and AlCl3 (5 mM) in improvement of the enzyme productivity. The Bacillus subtilis levansucrase was eluted as a single protein in one purification step. The enzyme molecular weight was (14 kDa). It showed its optimum activity at 45°C and could retain 60% of its activity after incubation at 50°C for 2 h. Its optimum activity was obtained at pH 8.2 and the enzyme showed great pH stability in both acidic and alkaline ranges. Unlike, most levansucrases all tested metals had an adverse effect in enzyme activity. The enzyme had antioxidant activities and were characterized as spherical micro‐ and nanoparticles by transmission electron microscopy. The effect of growth conditions and medium composition in levan structure and its fibrinolytic activity was evaluated. 相似文献
9.
Priya M. D'Costa Rukma S. S. Kunkolienkar Arti G. Naik Ravidas K. Naik Rajdeep Roy 《Journal of basic microbiology》2019,59(10):979-991
This study investigates the effect of metals (cadmium, lead, mercury, and tellurium) and organic pollutants (benzene, diesel, lindane, and xylene) on a dinoflagellate—Prorocentrum sigmoides Böhm—and its associated culturable bacteria. Two bacterial cultures (Bacillus subtilis strain PD005 and B. xiamensis strain PD006) were isolated from P. sigmoides and characterized by scanning electron microscopy, 16S ribosomal RNA sequencing, biochemical analyses, and growth curve studies. This study points to a mutualistic relationship between P. sigmoides and its associated Bacillus isolates. P. sigmoides enhanced the growth of its associated Bacillus spp., through the secretion of extracellular exudates. In return, both Bacillus isolates contributed to the resistance of P. sigmoides to metals and organic pollutants. P. sigmoides and both Bacillus isolates exhibited concentration‐dependent responses to metals and organic pollutants. An intriguing feature was the similar response of P. sigmoides and its associated Bacillus isolates to mercury and cadmium, indicating a co‐selection of mercury and cadmium resistance. This provides support to the “dinoflagellate host‐phycosphere bacteria” behaving as a single functional unit. However, the sensitivity profiles of P. sigmoides and its associated Bacillus isolates are different with respect to metals versus organic pollutants. These aspects need to be addressed in future studies to unravel the effect of metal and organic pollutants on dinoflagellates, an important component of the phytoplankton community, and to discern the influence of associated “phycosphere” bacteria on the response of dinoflagellates to pollutants. 相似文献
10.
《Vaccine》2022,40(44):6367-6373
IntroductionThe COVID-19 pandemic has affected the delivery of essential health services, such as routine immunization. We assessed the impact of the pandemic on the uptake of routine immunization in rural Gambia.MethodsWe collected real-time vaccine administration data in the Basse and Fuladu West Health & Demographic Surveillance Systems from September 01, 2019, to December 31, 2020. We assessed the monthly number of Expanded Program on Immunization (EPI) clinic attendances and vaccines administered, comparing data during the baseline period (September 01, 2019–March 31, 2020), COVID-19 interruption period (April 01–June 30, 2020), initial recovery period (Jul 01–September 30, 2020) and the late recovery period (October 01–December 31, 2020).ResultsCompared to the baseline period, there was an overall average monthly decline of 13.4% in EPI attendance and 38.3% reduction in average monthly immunizations during the interruption period. This decrease was particularly noticeable for Bacille Calmette-Guérin (BCG) (47.2%), birth dose hepatitis B (Hep B) (46.9%), 1st dose pentavalent (Penta1) (43.1%), 1st dose pneumococcal conjugate vaccine (PCV1) (42.4%), and measles vaccines (15.5%). Comparing the late recovery to baseline period, average monthly EPI attendance was 5.3% higher, with 1.9% increase in average monthly immunizations. Monthly immunizations for BCG were 3.0% greater, 2.5% greater for Hep B, 22.7% greater for oral polio vaccine (OPV1), 2.0% less for Penta1, 19.2% less for Penta2, and 2.6% less for PCV1.ConclusionThe reduced EPI attendance during the pandemic interruption period lasted only 3 months. Significant recovery in EPI attendance occurred during the late recovery period, while rates of monthly immunization returned to pre-pandemic levels for most antigens. EPI programmes should implement strategies to deliver missed antigens when infants do present to EPI clinics, aware that missed doses may be age dependent. 相似文献