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181.
A successful case of crossover replantation of the left foot to the stump of the right leg and temporary ectopic implantation of the right amputated foot on the forearm is described. The ectopically implanted right foot was used as a free fillet flap for the late reconstruction of the left leg stump. At the latest follow-up examination, 18 months after the accident, the patient was able to walk independently with a prosthesis on the stump of the left leg. Both the cross-replanted foot and the free filleted foot flap, used for the reconstruction of the left leg stump, have maintained adequate protective sensation. The importance of utilization of amputated parts for functional reconstruction is stressed. Crossover replantations and ectopic implantations should be considered in bilateral amputations for the salvage of at least one extremity.  相似文献   
182.
Moringa oleifera is a miracle plant rich in nutrients, antioxidants, and antibiotic properties. Present study was designed to evaluate various biochemical attributes of leaves and flowers of M. oleifera. Plant parts (leaves, flowers) of M. oleifera, collected from different roadsides of Multan district, Punjab, Pakistan, were used as experimental material. Result indicates that alkaloids, saponin, carbohydrates, fats, and protein had a high value in the aqueous extract of both leaves and flowers of M. oleifera. Whereas phenol content was high in methanolic leaves extract and the phenol contents were high in aqueous extract of flowers. The extract yield of M. oleifera leaves and flowers both showed a higher percentage in aqueous extract (57.5%), followed by methanol extract and lowest in ethyl acetate extract. Flavonoids contents were higher in ethyl acetate extract of leaves (33.67%) and aqueous extract of flowers (53.71%). While crude fiber was high in methanolic extract of leaves (12.40%) and in flowers crude fiber was high in ethyl acetate extract (15.86%). The moisture contents were higher in leaves (8.87%) than flowers (7.3%) and similarly, ash percentage in flowers (52.60%) than leaves (41.84%). Ethyl acetate extracts of M. oleifera leaves show antibacterial activity against Pseudomonas aeruginosa while methanolic extract of M. oleifera flowers shows antibacterial activity against Xanthomonas sp. Maximum growth inhibits show in all extracts of leaves against Aspergillus flavus, F. oxysporum, and P. glabrum except for the concentrated aqueous extract of leaves. While in flowers maximum growth inhibits all extracts against P. glabrum, A. niger, and A. flavus except the diluted ethyl acetate extract. Phytochemicals present in different parts of moringa have significant edible and commercial potential. Moringa extracts exhibited significant antimicrobial activity, therefore have applications in pharmaceuticals.  相似文献   
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A new exopolysaccharide (EPS) producing Gram-positive bacterium was isolated from the rhizosphere of Bouteloua dactyloides (buffalo grass) and its EPS product was structurally characterized. The isolate, designated as LB1-1A, was identified as Bacillus paralicheniformis based on 16S rRNA gene sequence and phylogenetic tree analysis. The EPS produced by LB1-1A was identified as a levan, having β(2?→?6) linked backbone with β(2?→?1) linkages at the branch points (4.66%). The isolate LB1-1A yielded large amount (~?42 g/l) of levan having high weight average molecular weight (Mw) of 5.517?×?107 Da. The relatively low degree of branching and high molecular weight of this levan makes B. paralicheniformis LB1-1A a promising candidate for industrial applications.

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185.
BackgroundBreast cancer is a multifactorial disease with the highest frequency in females. Genetic and environmental factors can cause mutation in several genes like tyrosine kinase, JAK2 gene which may initiate cancer. Molecular analysis of mutations in the JAK2 gene along with determination of environmental, clinical and haematological risk factors associated with breast cancer patients is need of hour to improve patient's healthcare. Somatic JAK2 valine-to-phenylalanine (617 codon) mutation is one of the widely prevalent mutations.MethodsBlood was collected from seventy breast cancer patients after their consent. The questionnaire included risk factors, age group, locality, number of children, tumor type, family history, time of initial diagnosis, no of cycles/month, water conditions and exposure to radiations. Molecular analysis were carried out from genomic DNA using Sanger sequencing and allele-specific PCR to check the V617F point mutation.ResultsThe breast cancer risk factors includes unfiltered water (68.57%), urban (58.57%), menopause (55.71%), family history of cancer (18.57%), tumor grades (II, 37.14% and III, 35.71%), consanguineous marriages (44.28%) and having more than 3–4 children (45.71%). Prevalence of breast cancer was higher after the age of 35 and maximum at 35–50. In allele-specific PCR of 70 patients, 25 patients were wild type (229 bp), 25 patients were with partially deleted gene (200 bp), and 20 patient had shown no or less than 40 bp size fragments. In Sanger's sequencing of 70 BC cases, 18% were found to be positive for V617F point mutation, including 6 homozygous (T/T) and 7 heterozygous (G/T) mutations at nucleotide position 1849 in exon 14 of the JAK2 gene.ConclusionsEnvironmental and clinical risk factors were associated with breast cancer which can be overcome by improving awareness of associated risks, health facilities and reducing stress.  相似文献   
186.
Despite recent advances in understanding the genetic bases of microcephaly, a large number of cases of microcephaly remain unexplained, suggesting that many microcephaly syndromes and associated genes have yet to be identified. Here, we report mutations in PYCR2, which encodes an enzyme in the proline biosynthesis pathway, as the cause of a unique syndrome characterized by postnatal microcephaly, hypomyelination, and reduced cerebral white-matter volume. Linkage mapping and whole-exome sequencing identified homozygous mutations (c.355C>T [p.Arg119Cys] and c.751C>T [p.Arg251Cys]) in PYCR2 in the affected individuals of two consanguineous families. A lymphoblastoid cell line from one affected individual showed a strong reduction in the amount of PYCR2. When mutant cDNAs were transfected into HEK293FT cells, both variant proteins retained normal mitochondrial localization but had lower amounts than the wild-type protein, suggesting that the variant proteins were less stable. A PYCR2-deficient HEK293FT cell line generated by genome editing with the clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 system showed that PYCR2 loss of function led to decreased mitochondrial membrane potential and increased susceptibility to apoptosis under oxidative stress. Morpholino-based knockdown of a zebrafish PYCR2 ortholog, pycr1b, recapitulated the human microcephaly phenotype, which was rescued by wild-type human PYCR2 mRNA, but not by mutant mRNAs, further supporting the pathogenicity of the identified variants. Hypomyelination and the absence of lax, wrinkly skin distinguishes this condition from that caused by previously reported mutations in the gene encoding PYCR2’s isozyme, PYCR1, suggesting a unique and indispensable role for PYCR2 in the human CNS during development.  相似文献   
187.
The interactions of biological macromolecules with nanoparticles underlie a wide variety of current and future applications in the fields of biotechnology, medicine and bioremediation. The same interactions are also responsible for mediating potential biohazards of nanomaterials. Some applications require that proteins adsorb to the nanomaterial and that the protein resists or undergoes structural rearrangements. This article presents a screening method for detecting nanoparticle-protein partners and conformational changes on time scales ranging from milliseconds to days. Mobile fluorophores are used as reporters to study the interaction between proteins and nanoparticles in a high-throughput manner in multi-well format. Furthermore, the screening method may reveal changes in colloidal stability of nanomaterials depending on the physicochemical conditions.  相似文献   
188.
The study of functional brain connectivity alterations induced by neurological disorders and their analysis from resting state functional Magnetic Resonance Imaging (rfMRI) is generally considered to be a challenging task. The main challenge lies in determining and interpreting the large-scale connectivity of brain regions when studying neurological disorders such as epilepsy. We tackle this challenging task by studying the cortical region connectivity using a novel approach for clustering the rfMRI time series signals and by identifying discriminant functional connections using a novel difference statistic measure. The proposed approach is then used in conjunction with the difference statistic to conduct automatic classification experiments for epileptic and healthy subjects using the rfMRI data. Our results show that the proposed difference statistic measure has the potential to extract promising discriminant neuroimaging markers. The extracted neuroimaging markers yield 93.08% classification accuracy on unseen data as compared to 80.20% accuracy on the same dataset by a recent state-of-the-art algorithm. The results demonstrate that for epilepsy the proposed approach confirms known functional connectivity alterations between cortical regions, reveals some new connectivity alterations, suggests potential neuroimaging markers, and predicts epilepsy with high accuracy from rfMRI scans.  相似文献   
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190.
Huntington disease (HD) is a neurodegenerative disorder associated with polyglutamine expansion in a recently identified protein, huntingtin. Huntingtin is widely expressed and plays a crucial role in development, because gene-targeted HD-/- mouse embryos die early in embryogenesis. To analyze the function of normal huntingtin, we have generated HD-/- embryonic stem (ES) cells and used an in vitro model of ES cell differentiation to analyze their ability to develop into neuronal cells. Expression analysis of wild-type ES cells revealed that huntingtin is expressed at all stages during ES cell differentiation with high expression in neurons. Expression levels increased with the maturation of differentiating neurons, demonstrating that expression of huntingtin is developmentally regulated in cell culture and resembles the pattern of expression observed in differentiating neurons in the mouse brain. It is interesting that HD-/- ES cells could differentiate into mature postmitotic neurons that expressed functional voltage- and neurotransmitter-gated ion channels. Moreover, both excitatory and inhibitory spontaneous postsynaptic currents were observed, indicating the establishment of functional synapses in the absence of huntingtin. These results demonstrate that huntingtin is not required for the generation of functional neurons with features characteristic of postmitotic neurons in the developing mouse brain.  相似文献   
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