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161.
162.
All extant species in the Rhinocerotidae family are experiencing escalating threats in the wild, making self-sustaining captive populations essential genetic reservoirs for species survival. Assisted reproductive technologies (ARTs) will become increasingly important for achieving and maintaining ex situ population sustainability and genetic diversity. Previous reports have shown that a large proportion of captive southern white rhinoceros (SWR) females are irregularly cyclic or acyclic, and that cycling females display two different estrous cycle lengths of approximately 30 or 70 days. It has been suggested that the longer estrous cycle length is infertile or subfertile, as no term pregnancies have been observed following long cycles. Here we report the achievement of two pregnancies following long luteal phases, using ovulation induction and artificial insemination with either fresh or frozen-thawed semen. One female SWR conceived on the first insemination attempt and gave birth to a live offspring. A second female conceived twice in consecutive long cycles although the first embryo was resorbed by 33 days post-insemination. A pregnancy from this female's second insemination is ongoing with expected parturition in November 2019. Whether prolonged estrous cycles in SWR are subfertile or infertile in natural breeding situations remains unclear. However, our findings demonstrate that the application of ARTs following prolonged cycles can result the successful establishment of pregnancies in SWR. Therefore, with ARTs, female SWR otherwise considered nonreproductive due to long estrous cycles may still have the potential for representation and contribution to the ex situ population.  相似文献   
163.
Osteoblasts play an important role in bone regeneration and repair. The hypoxia condition in bone occurs when bone undergoes fracture, and this will trigger a series of biochemical and mechanical changes to enable bone repair. Hence, it is interesting to observe the metabolites and metabolism changes when osteoblasts are exposed to hypoxic condition. This study has looked into the response of human osteoblast hFOB 1.19 under normoxic and hypoxic conditions by observing the cell growth and utilization of metabolites via Phenotype MicroArrays™ under these two different oxygen concentrations. The cell growth of hFOB 1.19 under hypoxic condition showed better growth compared to hFOB 1.19 under normal condition. In this study, osteoblast used glycolysis as the main pathway to produce energy as hFOB 1.19 in both hypoxic and normoxic conditions showed cell growth in well containing dextrin, glycogen, maltotriose, D-maltose, D-glucose-6-phospate, D-glucose, D-mannose, D-Turanose, D-fructose-6-phosphate, D-galactose, uridine, adenosine, inosine and α-keto-glutaric acid. In hypoxia, the cells have utilized additional metabolites such as α-D-glucose-1-phosphate and D-fructose, indicating possible activation of glycogen synthesis and glycogenolysis to metabolize α-D-glucose-1-phosphate. Meanwhile, during normoxia, D-L-α-glycerol phosphate was used, and this implies that the osteoblast may use glycerol-3-phosphate shuttle and oxidative phosphorylation to metabolize glycerol-3-phosphate.  相似文献   
164.
Plants dispense localised and systemic defense responses against biotic colonisers and plant resistance to pathogens depends upon timely recognition of pathogen infection and subsequent rapid activation of defense responses through signal transduction pathways. Induction of host defense responses involving compatible and incompatible interactions in tomato landrace, LE996, LE150 and LE1165 (Solanum lycopersicum), and wild relatives, Seijima Jeisei and I979 (S. hirsutum) genotypes, and early blight (EB) pathogen, Alternaria solani were studied. Accumulation patterns of different defense related proteins in resistant genotypes (LE996, Seijima jeisei and I979) and susceptible genotypes (LE150 and LE1165) are reported here. Challenge inoculation led to similar protein profiles in resistant genotypes yielding 11 proteins, unique are 14, 54, and 58 kD proteins that are absent with susceptible genotypes. Resistant genotypes accumulated more proteins well in advance, 6-h after challenge inoculation. Resistant genotype LE996 expressed 54%, 90%, and 52% enhanced enzymatic activity of peroxidase, polyphenol oxidase and phenylalanine ammonia lyase respectively than susceptible LE150 and correlated phenolics accumulation peaked 2-d after challenge inoculation. Activity gel assay indicated the unique expression of PO1 and PO2 in LE996 upon challenge inoculation. Significant increase in expression of chitinases (63%) and β-1,3-glucanase (71%) upon challenge inoculation than susceptible LE150 control was recorded. Western blotting indicated the unique presence of less than 30 kD chitinase in resistant LE996 and Seijima Jeisei and was absent in susceptible LE150. The results demonstrate the importance of pathogenesis-related (PR) proteins in EB resistance and their use as biochemical markers for genotype selection.  相似文献   
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166.
Probiotics and Antimicrobial Proteins - Probiotics play significant roles in enhancing systemic immunity, improving intestinal balance and feed value, enhancing enzymatic digestion, and inhibiting...  相似文献   
167.
Parkinson's disease is characterized by progressive cell death in the substantia nigra pars compacta, which leads to dopamine depletion in the striatum and indirectly to cortical dysfunction. Increased glutamatergic transmission in the basal ganglia is implicated in the pathophysiology of Parkinson's disease and glutamate receptor mediated excitotoxicity has been suggested to be one of the possible causes of the neuronal degeneration. In the present study, the effects of serotonin, gamma-aminobutyric acid and bone marrow cells infused intranigrally to substantia nigra individually and in combination on unilateral 6-hydroxydopamine induced Parkinson's rat model was analyzed. Scatchard analysis of total glutamate and NMDA receptor binding parameters showed a significant increase in Bmax (P < 0.001) in the cerebral cortex of 6-hydroxydopamine infused rat compared to control. Real Time PCR amplification of NMDA2B, mGluR5, bax, and ubiquitin carboxy-terminal hydrolase were up regulated in cerebral cortex of 6-hydroxydopamine infused rats compared to control. Gene expression studies of GLAST, ά-Synuclien and Cyclic AMP response element-binding protein showed a significant (P < 0.001) down regulation in 6-OHDA infused rats compared to control. Behavioural studies were carried out to confirm the biochemical and molecular studies. Serotonin and GABA along with bone marrow cells in combination showed reversal of glutamate receptors and behaviour abnormality shown in the Parkinson's rat model. The therapeutic significance in Parkinson's disease is of prominence.  相似文献   
168.
Thirty-eight cultures of sweet sorghum (Sorghum bicolor, Poaceae) at dead-ripe stage showed that the cultures IS 6962, IS 9889, PR 4579, and IS 707 contained higher amounts of total sugars per 100 ml of extractable juice. But total sugar yield was found to be high (>200 kg/ha) in IS 715, IS 724, IS 6962, and IS 9901. Though upper internodes contained comparatively higher sugar content than the bottom internodes, the seventh internode had the maximum. A highly positive correlation (+0.9828) was found to exist between total sugars and sucrose in the internodes. Fermentation of juice from IS 6962 yielded 240 litre of alcohol/ha. Roasted chickpea candies prepared from syrup of 73o brix resembled that from jaggery in taste and flavour.  相似文献   
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