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561.
Testis mediated gene transfer (TMGT) is a potential tool for making transgenic mice having more than 90% success rate. However, this method needs further standardization before it can be adapted in other species including livestock. In order to standardize the TMGT in goat, buck testes (n = 20) collected from the slaughter house were injected with a vector driving green fluorescent protein (GFP) expression under a cytomegalovirus (CMV) promoter. Then, the testes were subjected to electroporation with predetermined voltage, pulse length, pulse interval and number of pulses. Seminiferous tubules were isolated from the electroporated testis and cultured in-vitro. The expression was checked at regular intervals. Green fluorescence was observed on different days in different samples. It suggests transient integration of the plasmid into the seminiferous tubules. This in-vitro transfection of seminiferous tubule using electroporation will provide valuable baseline information.  相似文献   
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Proline with its unique geometrical feature generates turn in the peptide backbone. Therefore, aggregation potential of Aβ38 can be modulated by insertion of proline at specific positions. Although site specific proline mutation is reported, effect of multiple proline substitution on aggregation potential is still not demonstrated. Therefore, Aβ38, a single proline substituted variant, V18P-Aβ38, a double proline substituted variant, V18P-I31P-Aβ38 and a triple proline substituted version, V12P-V18P-I31P-Aβ38 were synthesized and their aggregation potential were studied. The proline mutants found to have higher solubility and slower aggregation kinetics. The double mutated version was relatively less aggregation prone than its single mutated version. Such analogues can be useful for designing new β sheet breaker peptides, studying the mechanism of aggregation and structural analyses.  相似文献   
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Prolonged diabetes ultimately leads to Diabetic Retinopathy (DR) which is one of the leading causes of preventable blindness in the world. Through advanced image analysis techniques are used for abnormalities detection in retina that define and correlate the severity of DR. A thorough study is done in this area in recent past years and on the basis of these studies we have developed a computer based prediction model that is used to determine the severity of DR. To identify severity DR, we have analyzed the human eye image. We have extracted some important features from human eye image i.e. Blood Artery, Optical disc, Exudates. Based on these image and data we have designed an automated system for the determination of DR severity. This automated DR severity assessment methods can be used to predict the clinical case and conditions when young clinicians would agree or disagree with their more experienced fellow members. The algorithms described in this study may be used in clinical practice to validate or invalidate the diagnoses. Algorithms or method developed here may also be used for pooling diagnostic knowledge for serving mankind. Here we have described a computational based low cost retinal diagnostic approach which can aid an ophthalmologist to quickly diagnose the various stages of DR. This system can accept retinal images and can successfully detect any pathological condition associated with DR.  相似文献   
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There is a growing need for sensitive and reliable nucleic acid detection methods that are convenient and inexpensive. Responsive and programmable DNA nanostructures have shown great promise as chemical detection systems. Here, we describe a DNA detection system employing the triggered self-assembly of a novel DNA dendritic nanostructure. The detection protocol is executed autonomously without external intervention. Detection begins when a specific, single-stranded target DNA strand (T) triggers a hybridization chain reaction (HCR) between two, distinct DNA hairpins (α and β). Each hairpin opens and hybridizes up to two copies of the other. In the absence of T, α and β are stable and remain in their poised, closed-hairpin form. In the presence of T, α hairpins are opened by toe-hold mediated strand-displacement, each of which then opens and hybridizes two β hairpins. Likewise, each opened β hairpin can open and hybridize two α hairpins. Hence, each layer of the growing dendritic nanostructure can in principle accommodate an exponentially increasing number of cognate molecules, generating a high molecular weight nanostructure. This HCR system has minimal sequence constraints, allowing reconfiguration for the detection of arbitrary target sequences. Here, we demonstrate detection of unique sequence identifiers of HIV and Chlamydia pathogens.  相似文献   
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More than half a century has passed since the introduction of the National Filariasis Control Program; however, as of 2023, lymphatic filariasis (LF) still prevails globally, particularly in the tropical and subtropical regions, posing a substantial challenge to the objective of worldwide elimination. LF is affecting human beings and its economically important livestock leading to a crucial contributor to morbidities and disabilities. The current scenario has been blowing up alarms of attention to develop potent therapeutics and strategies having efficiency against the adult stage of filarial nematodes. In this context, the exploration of a suitable drug target that ensures lethality to macro and microfilariae is now our first goal to achieve. Apoptosis has been the potential target across all three stages of filarial nematodes viz. oocytes, microfilariae (mf) and adults resulting in filarial death after receiving the signal from the reactive oxygen species (ROS) and executed through intrinsic and extrinsic pathways. Hence, it is considered a leading target for developing antifilarial drugs. Herein, we have shown the efficacy of several natural and synthetic compounds/nanoformulations in triggering the apoptotic death of filarial parasites with little or no toxicity to the host body system.  相似文献   
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Carboxymethyl guar gum (CMG) was structurally tailored with aqueous-nanosilica sol for controlled transdermal release of diclofenac sodium. Nanosilica was administered in low to moderately high concentration range to synthesize various, novel CMG-silica hybrid nanocomposites. Spectroscopy together with thermogravimetry, morphology, swelling and rheological studies proved that 1 wt% nanosilica content was the best physical formulation. The drug release studies from different hydrogel nanocomposites exhibited slower release than neat CMG. 1 wt% nanosilica loaded hydrogel nanocomposite gave slowest but steady release profile among all other nanocomposites due to its highly viscous nature owing to most compact microstructure.  相似文献   
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