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41.
Microelectrode mapping experiments indicate an ipsilateral representation of the oropharynx and a well-defined, bilateral input from the proximal portion of the maxillary barbels and snout region within the vagal lobe of channel catfish. The map of the oropharyngeal epithelium is distorted so that the gill arches are rotated through an angle of 90° along the transverse plane, and the dorsally mapped region of the gill rakers is tilted posteriorly in the sagittal plane of the vagal lobe. Multiunit recording studies fail to provide definitive boundaries of adjacently mapped domains of oropharyngeal structures. Gustatory receptive fields of neurons in the vagal lobe correspond to their location on the topological map obtained by tactile stimulation of the oropharyngeal epithelium. A few single unit recordings indicate restricted receptive fields and different response patterns of taste, tactile, and proprioceptive neurons in the vagal lobe of catfish.  相似文献   
42.
Presence of heavy metals including lead (Pb) in the textile effluents is a crucial factor affecting the growth and potential of the dye decolorizing bacterial strains. This work was planned to isolate and characterize a bacterial strain exhibiting the potential to decolorize a range of azo dyes as well as the resistance to Pb. In this study, several Pb tolerant bacteria were isolated from effluents of textile industry. These bacterial isolates were screened for their potential of decolorizing the reactive red-120 (RR120) azo dye with presence of Pb (50 mg L?1). The most efficient isolate was further characterized for its potential to resist Pb and decolorize different azo dyes under varying cultural and incubation conditions. Out of the total 82 tested bacterial isolates, 30 bacteria were found to have varying potentials to resist the presence of lead (Pb) and carry out decolorization of an azo dye reactive red-120 (RR120) in the medium amended with Pb (50 mg L?1). The most efficient selected bacterium, Pseudomonas aeruginosa strain HF5, was found to show a good potential not only to grow in the presence of considerable concentration of Pb but also to decolorize RR120 and other azo dyes in the media amended with Pb. The strain HF5 completely (>?90%) decolorized RR120 in mineral salt medium amended with 100 mg L?1 of Pb and 20 g L?1 NaCl. This strain also considerably (>?50%) decolorized RR120 up to the presence of 2000 mg L?1 of Pb and 50 g L?1 of NaCl but with reduced rate. The optimal decolorization of RR120 by HF5 was achieved when the pH of the Pb amended (100 mg L?1) mineral salt media was adjusted at 7.5 and 8.5. Interestingly, this strain also showed the tolerance to a range of metal ions with varying MIC values. The Pseudomonas aeruginosa strain HF5 harboring the unique potentials to grow and decolorize the azo dyes in the presence of Pb is envisaged as a potential bioresource for devising the remediation strategies for treatment of colored textile wastewaters loaded with Pb and other heavy metal ions.  相似文献   
43.
Bcl2-associated athanogene 3 (BAG3) mutations have been reported to cause the myofibrillar myopathy (MFM) which shows progressive limb muscle weakness, respiratory failure, and cardiomyopathy. Myopathy patients with BAG3 mutation are very rare. We described a patient showing atypical phenotypes. We aimed to find the genetic cause of Korean patients with sensory motor polyneuropathy, myopathy and rigid spine. We performed whole exome sequencing (WES) with 423 patients with sensory motor polyneuropathy. We found BAG3 mutation in one patient with neuropathy, myopathy and rigid spine syndrome, and performed electrophysiological study, whole body MRI and muscle biopsy on the patient. A de novo heterozygous p.Pro209Leu (c.626C>T) mutation in BAG3 was identified in a female myopathy. She first noticed a gait disturbance and spinal rigidity at the age of 11, and serum creatine kinase levels were elevated ninefolds than normal. She showed an axonal sensory-motor polyneuropathy like Charcot–Marie–Tooth disease (CMT), myopathy, rigid spine and respiratory dysfunction; however, she did not show any cardiomyopathy, which is a common symptom in BAG3 mutation. Lower limb MRI and whole spine MRI showed bilateral symmetric fatty atrophy of muscles at the lower limb and paraspinal muscles. When we track traceable MRI 1 year later, the muscle damage progressed slowly. As far as our knowledge, this is the first Korean patient with BAG3 mutation. We described a BAG3 mutation patient with atypical phenotype of CMT and myopathy, and those are expected to broaden the clinical spectrum of the disease and help to diagnose it.  相似文献   
44.
Genome sequence of hyperthermophilic archaeon Pyrobaculum calidifontis revealed the presence of an open reading frame, Pcal_0768, corresponding to a putative 4-α-glucanotranferase belonging to glycoside hydrolases (GH) family 77. We have produced, in Escherichia coli, and purified recombinant Pcal_0768 which exhibited high disproportionation (690 U mg?1) activity. To the best of our knowledge, this is the highest ever reported activity for any member of family GH77. Maltooligosaccharides, when used as sole substrates, were disproportionated into linear maltooligohomologues. The analysis of the reaction end products revealed no evidence for the production of cycloamyloses. Catalytic activity of the enzyme remained unchanged in the presence or the absence of ionic and nonionic detergents. γ-cyclodextrin, an inhibitor of 4-α-glucanotransferases, did not show any inhibitory effect on Pcal_0768 activity. These properties make Pcal_0768 a potential candidate for starch processing industry.  相似文献   
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46.
A simple synthesis of octyl 3,6-di-O-(-d-mannopyranosyl)--d-mannopyranoside is described. The key features of the synthetic scheme are the formation of the -mannosidic linkage by 1-O-alkylation of 2,3,4,6-tetra-O-acetyl-,-d-mannopyranose with octyl iodide and glycosylation of unprotected octyl -d-mannopyranoside using limiting acetobromomannose. The trisaccharide is shown to be an acceptor forN-acetylglucosaminyltransferase-I with aK M of 585 µm.  相似文献   
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48.

Genetic transformation of most indica rice (Oryza sativa) cultivars is hampered by poor in vitro culture performance and low regeneration potential. Histological study of primary calli can provide substantial information on their regeneration potential and can be used for early grading of calli expected to develop plantlets on regeneration media. The study was aimed to undertake histological analysis of primary calli derived from mature seeds of five indica rice cultivars viz. KSK-133, KS-282, Shaheen Basmati, Super Basmati, and DilRosh in order to assess their regeneration potential on different media combinations supplemented with various hormone concentrations (N6 + 2 mg/L 2,4-Dichlorophenoxyacetic acid; N6 + 2 mg/L 2–4 D + 2 mg/L Benzylaminopurine and MS + 2 mg/L 2,4-D). Calli with regeneration capability were subjected to histological assays by examining toulidine blue stained 5–8 μm thin sections for the presence of meristematic zones exhibiting embryogenic callus features. Based on our observations, formation of embryoids or embryoid-like structures was pronounced in KSK-133 and KS-282 calli. However, DilRosh, Super Basmati and Shaheen Basmati did not show these characteristic features. Three-week-old calli of all rice cultivars were transferred into regeneration medium (MS + 2 mg/L BAP + 1 mg/L Naphthaleneacetic acid). KSK-133 and KS-282 showed the highest regeneration potential (81% and 76%, respectively). These data were supported by histological observations where characteristic embryogenic units (EU) were noticed in these genotypes. These meristematic regions displayed high mitotic activity and stained relatively dark. The embryogenic calli cells were found heavily cytoplasmic with prominent nuclei and were located on the callus surface or inside surrounded by parenchymal cells.

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49.
The present study aimed to evaluate the bioaccumulation of some macrominerals in grazing buffaloes fed forage irrigated with sewage water or canal water. In particular, the transfer of sodium (Na), magnesium (Mg), potassium (K) and calcium (Ca) from soil to plant and in turn to animals was evaluated under sub-tropical environmental conditions. Samples of soil, forage and buffalo hair were collected and digested by wet method. Sodium and K concentrations were significantly higher in the soil but lower in the forages; however, Mg and Ca concentrations in both soil and forages were higher. The correlation between soil, forage and hair showed an imbalanced flow of Na, Mg and K and a balanced flow of Ca from soil to forage and then to animals. Based on the findings, the highest rates of transfer of minerals were found for sewage water treatment, whereas lowest rates were found for canal water treatment, except for Na. As the transfer of minerals depends on their bioavailability, the highest values may be due to the high rates of mineral uptake by plants. Thus, the high transfer rate of some elements by plants could become toxic in future causing detrimental effect to grazing livestock.  相似文献   
50.
MOTIVATION: Rhodopsin is a visual pigment present in rod cells of retina. It belongs to GPCR family and involves photoisomerization of 11-cis-retinal to all-trans-retinal isomers, conformational changes in rhodopsin and signal transduction cascade to generate a nerve impulse. This signaling pathway has been targeted to eliminate the effect of a mutation (Gly90→Asp) responsible for abnormal activation of G-protein without retinal conformations in the absence of light leading to congenital night blindness. A theoretical model of rhodopsin with induced mutation has been deliberated in order to find potential ligands which can offset this mutational effect. The binding interactions between the target mutated rhodopsin model and potential ligands have been predicted with the help of molecular docking. The results indicated strong functional benefits of ligands as an inhibitor and an agonist for mutated rhodopsin model. Therefore, we propose a new visual cascade model which can initiate the normal signaling of rhodopsin mutant with the help of proposed ligands and can provide a hope for vision in future.  相似文献   
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