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21.
Diarrhea is considered as an important cause of morbidity and mortality, even though one of the main reasons of death following diarrhea is initiated by dysentery. In recent years, the consumption of probiotics has been proposed for the treatment of infectious diarrhea. Despite most of the studies on probiotics have focused on acute watery diarrhea, few studies in the field of dysentery have found beneficial effects of probiotics. This study is a randomized double-blind clinical trial. The patients were randomly placed into control and case groups. In the intervention group, the patients received probiotics in the form of Kidilact® sachet, which contained high amounts of 7-strain friendly bacteria strains of Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Bifidobacterium infantis, Bifidobacterium breve, and Streptococcus thermophiles. On the other hand, the patients in the control group received placebo sachets on a daily basis for 5 days. It is notable that the treatment protocol of acute dysentery was done on both groups. The results of this study showed significant differences in the duration of blood in diarrhea between probiotic consumers (2.62 days) and the control group (3.16 days) (P value = 0.05). Additionally, significant differences in the average length of hospitalization in probiotic consumers (3.16 days) and control (3.66 days), (P value = 0.02) could be claimed that the consumption of probiotics is effective in reducing the duration of dysentery and diarrhea. The results of this study suggest that the use of probiotics can be effective in reducing the duration of blood in diarrhea. This study was also recorded in the Iran center of clinical trials registration database (IRCT2014060617985N1).  相似文献   
22.
Larvae of the cedar web-spinning sawfly, Cephalcia tannourinensis Chevin (Hymenoptera: Pamphiliidae), infected with a white fungus were collected from the Tannourine-Hadath El-Jebbeh cedar forest. Macro- and micro-morphological data based on the examination of colonies, conidiophores, and conidial shape of the fungus suggested a Beauveria species. Sequence analysis of the internal transcribed spacer regions of the isolated fungus showed that it is most closely related to isolates of B. bassiana Clade C. The present study showed that the isolated B. bassiana is a naturally occurring entomopathogenic fungus parasitizing the larvae of C. tannourinensis in Lebanon. Laboratory bioassays showed that B. bassiana caused high mortality of eggs and larvae. The infected eggs turned brownish in color, while larvae of the first instar ceased feeding and showed immobility and rigidity within 5 days and before sporulating conidial mat appeared on their cuticle. Second and third larval instars took longer time to show fungal sporulation: mortalities ranged between 85 and 100% within 7 days when treated with different conidial concentrations. The efficacy of control of C. tannourinensis using B. bassiana was higher or equal to the reference insect growth regulator, diflubenzuron, suggesting the possibility of its success as a biological control agent.  相似文献   
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This study is concerned with the co-production of alkaline proteases and thermostable α-amylase by some feather-degrading Bacillus strains: B. mojavensis A21, B. licheniformis NH1, B. subtilis A26, B. amyloliquefaciens An6 and B. pumilus A1. All strains produced both enzymes, except B. pumilus A1, which did not exhibit amylolytic activity. The best enzyme co-production was obtained by the NH1 strain when chicken feathers were used as nitrogen and carbon sources in the fermentation medium. The higher co-production of both enzymes by B. licheniformis NH1 strain was achieved in the presence of 7.5 g/l chicken feathers and 1 g/l yeast extract. Strong catabolic repression on protease and α-amylase production was observed with glucose. Addition of 0.5% glucose to the feather medium suppressed enzyme production by B. licheniformis NH1. The growth of B. licheniformis NH1 using chicken feathers as nitrogen and carbon sources resulted in its complete degradation after 24 h of incubation at 37°C. However, maximum protease and amylase activities were attained after 30 h and 48 h, respectively. Proteolytic activity profiles of NH1 enzymatic preparation grown on chicken feather or casein-based medium are different. As far as we know, this is the first contribution towards the co-production of α-amylase and proteases using keratinous waste. Strain NH1 shows potential use for biotechnological processes involving keratin hydrolysis and industrial α-amylase and proteases co-production. Thus, the utilization of chicken feathers may result in a cost-effective process suitable for large-scale production.  相似文献   
24.
All trans retinal was attached to both the primary face and the secondary face of beta-cyclodextrin via a Schiff base linkage, analogous to that in rhodopsin. The new models were evaluated and compared with n-butylamine retinylidene Schiff base for their rates of hydrolysis, and factors that influence such rates. Competition studies using adamantane carboxylate demonstrated the kinetic trap theory by diminishing the binding of retinal in the cyclodextrin, thereby augmenting the rate of hydrolysis. NMR experiments indicate that the retinylidene is most probably bound in the form of a dimer.  相似文献   
25.

Background and aims

In spite of the importance of Retama species for dune stabilization and re-vegetation and the contribution to the bio-fertilization of semi-arid and arid ecosystems, the symbiotic interaction of Retama species with rhizobia remains largely unstudied. In this paper, we aim to provide the first detailed study on nodule morphology and anatomy of Retama monosperma.

Methods

We collected nodules from coastal areas nearby Oran (Algeria) and studied in detail their anatomy and ultrastructure by light and electron microscopy.

Results

First, we confirmed the likely identity of the microsymbiont as B. retamae and found that nodules of R. monosperma belong to the genistoid type of indeterminate nodules. Infection threads, typical for most nodules of legumes, are absent in nodules of R. monosperma and bacterial spread is associated with plant cell division. The nitrogen fixation zone is homogenous with only invaded cells and a network of non-invaded cells found in many nodules, is absent. Moreover, endoreduplication does not take place in bacteroids in nodules of R. monosperma.

Conclusions

The features observed in this study are compared to the morphology and anatomy of nodules of other legumes and the possible consequences for nodule functioning and the mode of infection during the establishment of the interaction are discussed.  相似文献   
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Neuropilins and semaphorins are known as modulators of axon guidance, angiogenesis, and organogenesis in the developing nervous system, but have been recently evidenced as also playing a role in the immune system. Here we describe the expression and role of semaphorin 3F (SEMA3F) and its receptor neuropilin-2 (NRP2) in human T cell precursors. NRP2 and SEMA3F are expressed in the human thymus, in both lymphoid and non-lymphoid compartments. SEMA3F have a repulsive effect on thymocyte migration and inhibited CXCL12- and sphingosine-1-phosphate (S1P)-induced thymocyte migration by inhibiting cytoskeleton reorganization prior to stimuli. Moreover, NRP2 and SEMA3F are expressed in human T-cell acute lymphoblastic leukemia/lymphoma primary cells. In these tumor cells, SEMA3F also blocks their migration induced by CXCL12 and S1P. Our data show that SEMA3F and NRP2 are further regulators of human thymocyte migration in physiological and pathological conditions.  相似文献   
28.

Background

Decay Accelerating Factor (DAF) and Coxsackievirus-Adenovirus Receptor (CAR) have been identified as cellular receptors for Coxsackie B viruses (CV-B). The aim of this study is to elucidate the different binding properties of CV-B serotypes and to find out if there are any amino acid changes that could be associated to the different phenotypes.Twenty clinical CV-B isolates were tested on CaCo-2 cell line using anti-DAF (BRIC216) and anti-CAR (RmcB) antibodies. CV-B3 Nancy prototype strain and a recombinant strain (Rec, CV-B3/B4) were tested in parallel. The P1 genomic region of 12 CV-B isolates from different serotypes was sequenced and the Trans-Epithelial Electrical Resistance (TEER) along with the virus growth cycle was measured.

Results

Infectivity assays revealed clear differences between CV-B isolates with regard to their interactions with DAF and CAR. All tested CV-B isolates showed an absolute requirement for CAR but varied in their binding to DAF. We also reported that for some isolates of CV-B, DAF attachment was not adapted. Genetic analysis of the P1 region detected multiple differences in the deduced amino acid sequences.

Conclusion

Within a given serotype, variations exist in the capacity of virus isolates to bind to specific receptors, and variants with different additional ligands may arise during infection in humans as well as in tissue culture.  相似文献   
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