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1.
A simplified approach was devised to recycle sweet whey in production of spore-δ-endotoxin complex from certain entomopathogenic varieties ofBacillus thuringiensis Berliner. The process suggested aimed at the protection of the environment through dual channels namely biological oxygen demand (BOD) reduction of the byproduct under investigation and its incorporation in a microbial fermentation for production of pollution-free biological insecticides. The sweet whey could be used successfully for endotoxin production as complete fermentation media both as such and with simple treatments. Supplementation of whey media with ground leguminous seeds and fodder yeast resulted in marked increase in the yields of endotoxin produced but the toxicity was not increased proportionnally. Standard biological assays revealed high efficiency of certain strains ofB.t. var.entomocidus, kurstaki andgalleriae in producing endotoxins highly active against 3rd instar larvae ofSpodoptera littoralis Boisduval,Spodoptera exigua Hübner andHeliothis armigera Hübner. The suggested approach and the findings obtained are discussed in view of their application feasibilities.
Résumé Une méthode simplifiée a été mise au point pour recycler le petit lait dans la production du complexe spore-δ-endotoxine de certaines variétés entomopathogènes deBacillus thuringiensis Berliner. Le procédé proposé a pour but la protection de l'environnement par un double canal chimique, c'est-à-dire la réduction de la demande biologique en oxygène du sous produit étudié et son incorporation dans une fermentation microbienne pour la fabrication d'insecticides biologiques non polluants. Le petit lait peut être employé avec succès pour la production d'endotoxine à la fois en tant que milieux complets de fermentation et avec des traitements simples. L'addition aux milieux à base de petit lait de graines de légumineuses et de levure alimentaire aboutit à une augmentation sensible des rendements en endotoxine mais la toxicité n'est pas accrue en proportion. Des essais biologiques normalisés montrent une activité élevée de certaines souches deB.t. var.entomocidus, kurstaki etgalleriae qui produisent des endotoxines très actives à l'égard des larves de 3e stage deSpodoptera littoralis Boisduval,Spodoptera exigua Hübner etHeliothis armigera Hübner. La méthode proposée et les résultats obtenus sont discutés en vue de leur faisabilité d'application.
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Background

Tuberculosis (TB) is a major public health problem globally. Little is known about TB incidence in adolescents who are a proposed target group for new TB vaccines. We conducted a study to determine the TB incidence rates and risk factors for TB disease in a cohort of school-going adolescents in a high TB burden area in South Africa.

Methods

We recruited adolescents aged 12 to 18 years from high schools in Worcester, South Africa. Demographic and clinical information was collected, a tuberculin skin test (TST) performed and blood drawn for a QuantiFERON TB Gold assay at baseline. Screening for TB cases occurred at follow up visits and by surveillance of registers at public sector TB clinics over a period of up to 3.8 years after enrolment.

Results

A total of 6,363 adolescents were enrolled (58% of the school population targeted). During follow up, 67 cases of bacteriologically confirmed TB were detected giving an overall incidence rate of 0.45 per 100 person years (95% confidence interval 0.29–0.72). Black or mixed race, maternal education of primary school or less or unknown, a positive baseline QuantiFERON assay and a positive baseline TST were significant predictors of TB disease on adjusted analysis.

Conclusion

The adolescent TB incidence found in a high burden setting will help TB vaccine developers plan clinical trials in this population. Latent TB infection and low socio-economic status were predictors of TB disease.  相似文献   
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Glycoprotein IIb/IIIa receptor inhibitors represent a relatively new therapeutic approach in the field of antiplatelet therapy. Following the development of abciximab a number of small molecule GPIIb/IIIa inhibitors have been introduced such as tirofiban and eptifibatide. In this fast-moving field the interventional cardiologist needs a framework to guide decision-making for the individual patient. This review covers the efficacy and safety data from the clinical trials of GPIIb/IIIa inhibitors in the context of patients undergoing percutaneous coronary intervention for unstable angina/non-Q-wave myocardial infarction. There is an increasing body of evidence to support the efficacy of GPIIb/IIIa inhibitors in reducing the risk of adverse ischemic events in high and low risk patients undergoing percutaneous coronary intervention. A number of unresolved efficacy and safety issues remain, including the duration of treatment before and after intervention; whether a reduction in the heparin dose would further decrease the risk of hemorrhage without affecting the periprocedural thrombotic rate in patients undergoing PTCA with adjunctive GPIIb/IIIa inhibitors; and the cost-effectiveness of this therapy. When a thorough analysis of cost-effectiveness has been made, it will be easier to advocate the widespread use of these agents in all patients undergoing coronary intervention.  相似文献   
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Advances in reconstructive surgery have allowed for impressive salvage after severe lower-extremity trauma but not without complications when compared with immediate below-knee amputation. Several amputation index scores have been developed to help predict successful salvage as defined by a viable rather than a functional extremity. The purpose of this study was to evaluate retrospectively the predictive value of the amputation index scores and to assess prospectively overall health status and specific dysfunction in successful limb salvage and primary and secondary amputation by administering standardized generic and specific outcomes questionnaires (Medical Outcomes Study 36-Item Short-Form Health Survey, Western Ontario and MacMaster Universities Osteoarthritis Index). A retrospective chart review identified 55 severe lower-extremity injuries (Gustilo Type IIIB and IIIC) over a 12-year period (1984 to 1996). Forty-six severe open tibial fractures in 45 patients underwent attempted salvage. All required soft-tissue coverage by either local or free flap or vascular repair for leg salvage. The attempted-salvage group was subdivided into successful salvage and secondary amputation. The other nine patients underwent a primary amputation. There were no statistically significant differences in terms of patient demographics or other injuries (Injury Severity Score) in the three groups. Forty-eight of 54 patients with an average 5-year follow-up completed a validated generic and specific outcomes health questionnaire. In the attempted-salvage group, 89 percent of patients had a successful salvage and 11 percent came to a secondary amputation. The amputation index scores correctly predicted an amputation in 32 percent of patients. The magnitude of the amputation index scores did not correlate with the physical outcomes scores and were not found to add any significant value of information to the surgeon's decision making. Patients undergoing primary and secondary amputation had a worse physical outcomes score (28 versus 38) than successful salvage (p < 0.007). Even so, the SF-36 (physical component score) outcomes score for this group of injured extremities, regardless as to whether salvaged or amputated, was as low as or lower than that of many serious medical illnesses, suggesting that severe lower-extremity trauma impairs health as much as or more than being seriously ill. The mental component score in this group was comparable to that of a healthy population (49 versus 50), which implies the disability is primarily physical rather than psychological. Ninety-two percent of patients preferred their salvaged leg to an amputation at any stage of their injury, and none would have preferred a primary amputation.  相似文献   
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Boophilus annulatus, Hyalomma excavatum and Rhipicephalus sanguineus ticks were shown to be susceptible to different entomopathogenic fungi under laboratory conditions. Comparative results of bioassays using five different fungal species showed that some strains of Metarhizium anisopliae are highly pathogenic against various tick stages tested. In contrast to their activity against insects, fungi also affected tick eggs. All tested tick stages including those feeding on a host were found to be susceptible to these fungi, except for adult H. excavatum ticks, which were relatively resistant. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Aims

As one of the five Lactate dehydrogenase (LDH) isoenzymes, LDH5 has the highest efficiency to catalyze pyruvate transformation to lactate. LDH5 overexpression in cancer cells induces an upregulated glycolytic metabolism and reduced dependence on the presence of oxygen. Here we analyzed LDH5 protein expression in a well characterized large cohort of primary lung cancers in correlation to clinico-pathological data and its possible impact on patient survival.

Methods

Primary lung cancers (n = 269) and non neoplastic lung tissue (n = 35) were tested for LDH5 expression by immunohistochemistry using a polyclonal LDH5 antibody (ab53010). The results of LDH5 expression were correlated to clinico-pathological data as well as to patient's survival. In addition, the results of the previously tested Transketolase like 1 protein (TKTL1) expression were correlated to LDH5 expression.

Results

89.5% (n = 238) of NSCLC revealed LDH5 expression whereas LDH5 expression was not detected in non neoplastic lung tissues (n = 34) (p < 0.0001). LDH5 overexpression was associated with histological type (adenocarcinoma = 57%, squamous cell carcinoma = 45%, large cell carcinoma = 46%, p = 0.006). No significant correlation could be detected with regard to TNM-stage, grading or survival. A two sided correlation between the expression of TKTL1 and LDH5 could be shown (p = 0.002) within the overall cohort as well as for each grading and pN group. A significant correlation between LDH5 and TKTL1 within each histologic tumortype could not be revealed.

Conclusions

LDH5 is overexpressed in NSCLC and could hence serve as an additional marker for malignancy. Furthermore, LDH5 correlates positively with the prognostic marker TKTL1. Our results confirm a close link between the two metabolic enzymes and indicate an alteration in the glucose metabolism in the process of malignant transformation.  相似文献   
10.
The synthesis of hydrophobic plastic films was performed by acylation of agaroids with lauroyl chloride in the N,N-dimethylacetamide homogeneous system. All the plastic films were characterized by FT-IR spectroscopy and their degrees of substitution (DS) was deduced from their 1H-NMR spectra. In addition, thermomechanical feature of plastic films were analyzed and compared to those obtained from other kinds of hydrophobic plastic films. Latin square design of experiments helped us to determine optimized experimental conditions and identify the most important factors. Hence, mild conditions of acylation (90∘C, 1 eq/OH of lauroyl chloride, 1 eq/OH of 4-dimethylaminopyridine, 5,min) led to the production of highly substituted plastic films (DS = 3.62; maximum 4) with a high weight yield (211%) displaying mechanical properties close to polyethylene low density.  相似文献   
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