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61.
瞿理华 《齐鲁药事》2014,(3):182-183,186
目的观察卡介菌多糖核酸治疗白癜风的临床疗效。方法将68例白癜风患者随机分为两组,治疗组36例肌注卡介菌多糖核酸注射液联合外用30%补骨脂酊,对照组32例单纯外用30%补骨脂酊,给药3个月。分别用流式细胞术和ELISA方法检测卡介苗多糖核酸治疗白癜风前后患者外周血T细胞亚群、IL-10和IFN-γ的水平。结果治疗组总有效率为91.7%,对照组总有效率59.4%,治疗组显著优于对照组(P<0.01)。卡介菌多糖核酸治疗后,患者CD4+百分比及CD4+/CD8+比值较治疗前升高,CD8+百分比降低,IFN-γ水平升高(P<0.05),IL-10水平下降(P<0.05)。结论卡介菌多糖核酸可显著改善患者细胞免疫功能,能有效治疗白癜风。  相似文献   
62.

Background

Although maintenance bacillus Calmette-Guérin (BCG) is the recommended treatment in high-risk non–muscle-invasive bladder cancer (NMIBC), its efficacy in older patients is controversial.

Objective

To determine the effect of age on prognosis and treatment outcome in patients with stage Ta T1 NMIBC treated with maintenance BCG.

Design, setting, and participants

A total of 957 patients with intermediate- or high-risk Ta T1 (without carcinoma in situ) NMIBC were randomized in European Organization for Research and Treatment of Cancer (EORTC) trial 30911 comparing six weekly instillations of epirubicin, BCG, and BCG plus isoniazid followed by three weekly maintenance instillations over 3 yr.

Outcome measurements and statistical analysis

Cox multivariate proportional hazards regression models were used to assess the relative importance of age for recurrence, progression, overall survival, and NMIBC-specific survival with adjustment for EORTC risk scores.

Results and limitations

Overall, 822 eligible patients were included: 546 patients in the BCG with or without INH arms and 276 in the epirubicin arm. In patients treated with BCG with or without INH, 34.1% were >70 yr of age and 3.7% were >80 yr. With a median follow-up of 9.2 yr, patients >70 yr had a shorter time to progression (p = 0.028), overall survival (p < 0.001), and NMIBC-specific survival (p = 0.049) after adjustment for EORTC risk scores in the multivariate analysis. The time to recurrence was similar compared with the younger patients. BCG was more effective than epirubicin for all four end points considered, and there was no evidence that BCG was any less effective compared with epirubicin in patients >70 yr.

Conclusions

In intermediate- and high-risk Ta T1 urothelial bladder cancer patients treated with BCG, patients >70 yr of age have a worse long-term prognosis; however, BCG is more effective than epirubicin independent of patient age.

Patient summary

Intravesical bacillus Calmette-Guérin for non–muscle-invasive bladder cancer is less effective in patients >70 yr of age, but it is still more effective than epirubicin.

Trial registration

This study was registered with the US National Cancer Institute clinical trials database (protocol ID: EORTC 30911; http://www.cancer.gov/clinicaltrials/search/view?cdrid=77075&version=HealthProfessional&protocolsearchid=12442243#StudyIdInfo_CDR0000077075).  相似文献   
63.
Bacillus thuringiensis (Bt) is the best known and most widely used of all pesticidal microbes. The aim of this study was to assess the toxicity of a new formulation of Bacillus thuringiensis var israelensis SH-14 in rats through acute dermal toxicity, dermal and eye irritation experiments. The acute dermal toxicity and dermal and eye irritation studies were performed using rabbits according to the United States Environmental Protection Agency guidelines 885.3100, 870.2500 and 870.2500, respectively. The skin sensitization study was carried out in accordance to the EPA OPPTS 870.2600 using guinea pigs. There was no mortality and no evidence of treatment-related toxicity in acute dermal toxicity test. No dermal responses, including erythema/eschar or edema, were found in rabbits treated with the new formulation of Bti SH-14. Minimum response was observed after eye application of test substance. No skin sensitization reactions were observed after the challenge with the new formulation of Bti SH-14 in the Bti SH-14-treated guinea pigs. In summary, the present study demonstrated that the new formulation of Bti SH-14 is not acutely toxic via dermal route, has low eye irritation and would not cause dermal irritation or hypersensitivity to tested animals.  相似文献   
64.
目的 对海洋芽孢杆菌B-9987中macrolactin生物合成基因簇及其关键基因进行分析、鉴定及功能研究。方法 通过生物信息学手段对基因簇的基因组成和功能结构域进行了分析;构建了用于酰基转移酶基因高表达的大肠杆菌—芽孢杆菌穿梭载体,采用电击转化方法导入B-9987之中进行高表达。 结果 macrolactins是由位于同一个操纵子的8个基因bmmA-I所编码的反式酰基转移酶聚酮合酶体系组装而成,反式酰基转移酶(trans-acyltransferase,trans-AT)BmmA的高表达使macrolactin A的产量提高了约0.6倍。结论 macrolactin生物合成基因簇在具有生物防治活性的芽孢杆菌中普遍存在,且高度保守;反式酰基转移酶的高表达能够增加macrolactin A的产量。  相似文献   
65.
In August 2012, the Centers for Disease Control and Prevention, in partnership with the Association of Maternal and Child Health Programs, convened a meeting of national subject matter experts to review key clinical elements of anthrax prevention and treatment for pregnant, postpartum, and lactating (P/PP/L) women. National experts in infectious disease, obstetrics, maternal fetal medicine, neonatology, pediatrics, and pharmacy attended the meeting, as did representatives from professional organizations and national, federal, state, and local agencies. The meeting addressed general principles of prevention and treatment for P/PP/L women, vaccines, antimicrobial prophylaxis and treatment, clinical considerations and critical care issues, antitoxin, delivery concerns, infection control measures, and communication. The purpose of this meeting summary is to provide updated clinical information to health care providers and public health professionals caring for P/PP/L women in the setting of a bioterrorist event involving anthrax.  相似文献   
66.
Where wildlife disease requires management, culling is frequently considered but not always effective. In the British Isles, control of cattle tuberculosis (TB) is hindered by infection in wild badger (Meles meles) populations. Large-scale badger culling can reduce the incidence of confirmed cattle TB, but these benefits are undermined by culling-induced changes in badger behavior (termed perturbation), which can increase transmission among badgers and from badgers to cattle. Test–vaccinate/remove (TVR) is a novel approach that entails testing individual badgers for infection, vaccinating test-negative animals, and killing test-positive animals. Imperfect capture success, diagnostic sensitivity, and vaccine effectiveness mean that TVR would be expected to leave some infected and some susceptible badgers in the population. Existing simulation models predict that TVR could reduce cattle TB if such small-scale culling causes no perturbation, but could increase cattle TB if considerable perturbation occurs. Using data from a long-term study, we show that past small-scale culling was significantly associated with four metrics of perturbation in badgers: expanded ranging, more frequent immigration, lower genetic relatedness, and elevated prevalence of Mycobacterium bovis, the causative agent of TB. Though we could not reject the hypothesis that culling up to three badgers per social group might avoid perturbation, we also could not reject the hypothesis that killing a single badger prompted detectable perturbation. When considered alongside existing model predictions, our findings suggest that implementation of TVR, scheduled for 2014, risks exacerbating the TB problem rather than controlling it. Ongoing illegal badger culling is likewise expected to increase cattle TB risks.Infectious diseases are often difficult to control where wildlife hosts contribute to pathogen persistence. Wildlife culling is a frequently considered control option, which is sometimes effective (1, 2), but often ineffective (36).In the United Kingdom, the cattle farming industry is seriously affected by bovine tuberculosis (TB) caused by Mycobacterium bovis (7). Selective culling of test-positive cattle has helped to eradicate TB across much of the developed world, but eradication from the United Kingdom is impeded by M. bovis infection in European badgers (Meles meles) (8), as well as by continued transmission among cattle (911). Transmission has also been documented among badgers (12), from cattle to badgers (13), and from badgers to cattle (14, 15). Because badgers are clearly a contributing factor to the UK’s TB problem, successive TB control policies have included culling of badgers (7, 8). To date, cattle controls have emphasized selective slaughter of test-positive animals, whereas badger culls have typically been nonselective, with no testing of live animals before culling (but see ref. 16).The impacts of nonselective badger culling on M. bovis transmission are well established. Such culling reduces badger density (17), but also promotes dispersal into the culled area (18) as well as expanding badger ranging in and around the areas where culls occurred (19). In Britain these behavioral changes—termed social perturbation—have been linked to increases in the proportion of badgers infected with M. bovis (13, 20), and reductions in the spatial clustering of infection (21). In cattle, the incidence of confirmed TB was reduced inside large culling areas where badger numbers were substantially suppressed by annual “proactive” culling. However, on adjoining unculled lands, and in areas receiving localized “reactive” culling, reductions in badger numbers were smaller, the incidence of confirmed cattle TB was elevated (14, 15, 2224), and spatial clustering of cattle infection was reduced (21).This propensity of nonselective badger culling to prompt social perturbation and hence increase disease transmission is a major constraint on its utility as a tool for controlling cattle TB. An alternative approach, first proposed in the 1980s, would be to target culling at test-positive badgers, just as current controls target test-positive cattle (16, 25). A further elaboration, termed test–vaccinate/remove (TVR), involves killing test-positive badgers while vaccinating test-negative badgers. A pilot TVR program is scheduled to take place across 100 sq km in Northern Ireland in 2014 (26).Selective culling approaches (such as TVR) are likely to remove relatively small numbers of badgers. First, constraints on capture success limit testing to 56–85% of the badger population (27, 28). Second, not all captured badgers will be infected with M. bovis: in the 10 initial proactive culls of the Randomized Badger Culling Trial (RBCT), 2–38% of badgers had infection detectable by bacterial culture at standard necropsy (29). Third, not all infected badgers are detectable by available live tests: the only available trap-side test detected 49% of badgers that were culture-positive at necropsy (30), and standard necropsy itself detected only 55% of infected badgers (31). This combination of imperfect capture success, low average infection prevalence, and imperfect test sensitivity means that the numbers of badgers to be killed by selective culling would probably be low, usually just one or two badgers within a social group (32). The same factors, combined with incomplete vaccine efficacy (33), mean that some infected and some susceptible badgers would be expected to remain despite implementation of TVR.Simulations indicate that the likely consequences of TVR for cattle TB control are highly sensitive to assumptions about whether culling small numbers of badgers prompts social perturbation (34, 35). Neither cage trapping for testing nor vaccination has been found to cause behavioral change. If the culling component of TVR likewise causes no perturbation, then TVR is predicted to reduce the prevalence of M. bovis infection in badgers and hence the incidence of cattle TB (34, 35). However, if TVR causes perturbation similar to that associated with past large- and small-scale culling, then it is projected to prompt sustained (34) or transient (35) increases in cattle TB. Unfortunately, it is not known which of these scenarios is more likely. Although the behavioral and epidemiological consequences of nonselective culling are relatively well understood, there have been no empirical studies of badgers’ behavioral responses to killing small numbers of animals per social group, as would occur under TVR and other forms of selective culling.In this paper, we use data from a large-scale study to assess whether killing small numbers of badgers would be expected to prompt social perturbation. We compare patterns of badger movement and M. bovis infection at the start of the RBCT (conducted 1998–2005) (14) with two indices of badger mortality. Our first measure, road density, provides an index of the numbers of badgers killed in road accidents (36), an important cause of badger mortality in Britain (37, 38). Our second measure is prior nonselective culling, conducted during the period 1986–1998 as small-scale badger removal operations (BROs), which typically targeted single farms (8). We hypothesized that high road densities and intense prior culling would each lead to expanded badger movement and elevated M. bovis prevalence. Further, we hypothesized that perturbation might be avoided if the number of badgers killed remained below a certain threshold, and sought to estimate this threshold.  相似文献   
67.
This study describes the insecticidal activity of a novel Bacillus thuringiensis Cry-related protein with a deduced 799 amino acid sequence (~89 kDa) and ~19% pairwise identity to the 95-kDa-aphidicidal protein (sequence number 204) from patent US 8318900 and ~40% pairwise identity to the cancer cell killing Cry proteins (parasporins Cry41Ab1 and Cry41Aa1), respectively. This novel Cry-related protein contained the five conserved amino acid blocks and the three conserved domains commonly found in 3-domain Cry proteins. The protein exhibited toxic activity against the green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae) with the lowest mean lethal concentration (LC50 = 32.7 μg/mL) reported to date for a given Cry protein and this insect species, whereas it had no lethal toxicity against the Lepidoptera of the family Noctuidae Helicoverpa armigera (Hübner), Mamestra brassicae (L.), Spodoptera exigua (Hübner), S. frugiperda (J.E. Smith) and S. littoralis (Boisduval), at concentrations as high as ~3.5 μg/cm2. This novel Cry-related protein may become a promising environmentally friendly tool for the biological control of M. persicae and possibly also for other sap sucking insect pests.  相似文献   
68.
Parasporin is the cytocidal protein present in the parasporal inclusion of the non-insecticidal Bacillus thuringiensis strains, which has no hemolytic activity but has cytocidal activities, preferentially killing cancer cells. In this study, we characterized a cytocidal protein that belongs to this category, which was designated parasporin-5 (PS5). PS5 was purified from B. thuringiensis serovar tohokuensis strain A1100 based on its cytocidal activity against human leukemic T cells (MOLT-4). The 50% effective concentration (EC50) of PS5 to MOLT-4 cells was approximately 0.075 μg/mL. PS5 was expressed as a 33.8-kDa inactive precursor protein and exhibited cytocidal activity only when degraded by protease at the C-terminal into smaller molecules of 29.8 kDa. Although PS5 showed no significant homology with other known parasporins, a Position Specific Iterative-Basic Local Alignment Search Tool (PSI-BLAST) search revealed that the protein showed slight homology to, not only some B. thuringiensis Cry toxins, but also to aerolysin-type β-pore-forming toxins (β-PFTs). The recombinant PS5 protein could be obtained as an active protein only when it was expressed in a precursor followed by processing with proteinase K. The cytotoxic activities of the protein against various mammalian cell lines were evaluated. PS5 showed strong cytocidal activity to seven of 18 mammalian cell lines tested, and low to no cytotoxicity to the others.  相似文献   
69.
70.
ObjectiveLaboratory quality control (QC) is essential to assess the reliability of tuberculosis diagnostic testing. To provide safe QC reagents for the detection of drug-resistant Mycobacterium tuberculosis, we generated antibiotic-resistant mycobacterial strains of attenuated virulence (M. bovis bacillus Calmette–Guérin (BCG)).MethodsSeven mono-resistant BCG strains were developed by introducing resistance-conferring mutations into wild-type BCG strains. Mutations were confirmed by dideoxynucleotide sequencing. Phenotypic resistance was quantified by microbroth dilution to determine the MIC90. The capacity of two commercial tests (GeneXpert TB/RIF and Genotype MTBDRplus) to detect resistance-conferring mutations was evaluated independently.ResultsOur panel included BCG strains with mutations in rpoB (S450L, I491F), katG (deletion at AA428), gyrA (D94G), rpsL (K43R) and Rv0678c (S63R). These mutations translated respectively into phenotypic resistance to rifampin (MIC ≥8 mg/L), isoniazid (MIC ≥8 mg/L), moxifloxacin (MIC 4 mg/L) and streptomycin (MIC ≥8 mg/L); the Rv0678c mutant showed decreased susceptibility to both clofazimine (MIC 4 mg/L) and bedaqualine (MIC 1 mg/L). GeneXpert (Cepheid) and Genotype MTBDRplus (Hain Lifesciences) both called the rpoB S450L strain rifampin-resistant and the I491F mutant rifampin-susceptible, as expected based on single nucleotide polymorphism positions. Likewise, MTBDRplus called the novel katG deletion mutant isoniazid susceptible despite phenotypic resistance.ConclusionBCG strains engineered to be mono-resistant to anti-tuberculosis drugs can be used as safe QC reagents for tuberculosis diagnostics and drug susceptibility testing.  相似文献   
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