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Immobilization depicts a propitious route to optimize the catalytic performances, efficient recovery, minimizing autocatalysis, and also augment the stabilities of enzymes, particularly in unnatural environments. In this opinion, supramolecules and multimolecular frameworks have captivated immense attention to achieve profound controllable interactions between enzyme molecules and well-defined natural or synthetic architectures to yield protein bioconjugates with high accessibility for substrate binding and enhanced enantioselectivities. This scholastic review emphasizes the possibilities of associating multimolecular complexes with biological entities via several types of interactions, namely covalent interactions, host–guest complexation, interactions, intra/inter hydrogen bondings, electrostatic interactions, and so forth offers remarkable applications for the modulations of enzymes. The potential synergies between artificial supramolecular structures and biological systems are the primary concern of this pedagogical review. The majority of the research primarily focused on the dynamic biomolecule-responsive supramolecular assemblages and multimolecular architectures as ideal platforms for the recognition and modulation of proteins and cells. Embracing sustainable green demeanors of enzyme immobilizations in a quest to reinforce site-selectivity, catalytic efficiency, and structural integrality of enzymes are the contemporary requirements of the biotechnological sectors that instigate the development of novel biocatalytic systems. 相似文献
703.
Angus de Wilton Dinesh Aggarwal Hans Rolf Jger Hadi Manji Peter L. Chiodini 《PLoS neglected tropical diseases》2021,15(2)
BackgroundNeuroschistosomiasis is a severe complication of schistosomiasis, triggered by the local immune reaction to egg deposition, with spinal cord involvement the most well recognised form. Early treatment with praziquantel and high dose steroids leads to a reduction of neurological sequelae. The rarity of this condition in returning travellers to high income countries can result in delayed diagnosis and treatment. We aimed to evaluate the diagnosis and management of neuroschistosomiasis in a UK national referral centre.Materials/MethodsA retrospective review of confirmed clinical cases of spinal schistosomiasis referred to the Hospital for Tropical Diseases, UK, between January 2016 and January 2020 was undertaken. Electronic referral records were interrogated and patient demographic, clinical, laboratory, and radiological data collected.ResultsFour cases of neuroschistosomiasis were identified. The median age at diagnosis was 28 (range 21 to 50) with three male patients. All patients had epidemiological risk factors for schistosomiasis based on travel history and freshwater exposure; two in Uganda (River Nile), one in Malawi and one in Nigeria. All patients presented with features of transverse myelitis including back pain, leg weakness, paraesthesia and urinary dysfunction. The mean time from presentation to health services to definitive treatment was 42.5 days (range 16–74 days). Diagnosis was confirmed with CSF serology for schistosomiasis in all cases. Radiological features on MRI spine included enhancement focused predominantly in the lower thoracic spinal cord in three cases and the conus in one patient. All patients received a minimum of three days of oral praziquantel and high dose steroids. At three-month follow-up, one patient had complete resolution of symptoms and three had residual deficit; one patient was left with urinary and faecal incontinence, another had urinary retention, and the final patient has persistent leg pains and constipation.ConclusionWe observed a marked delay in diagnosis of neuroschistosomiasis in a non-endemic country. We advocate undertaking a thorough travel history, early use of imaging and CSF schistosomal serology to ensure early diagnosis of neuroschistosomiasis in patients presenting with consistent symptoms. If schistosomal diagnostics are not immediately available, presumptive treatment under the guidance of a tropical medicine specialist should be considered to minimize the risk of residual disability. We advocate for consensus guidelines to be produced and reporting to be performed in a uniform way for patients with spinal schistosomiasis. 相似文献
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Sunita Kaushish Aditya Kumar Ashok Aggarwal Vipin Parkash 《Indian journal of microbiology》2012,52(2):295-299
Two arbuscular mycorrhizal fungi, Glomus mosseae and Acaulospora laevis either alone or in combination with Trichoderma viride showed the dependence of Rauwolfia serpentina on endomycorrhizal fungi. After 60 days, G. mosseae singly or in combination with Trichoderma viride showed enhanced height increment compared to control plants. Maximum phosphorus content was shown by plants treated with G. mosseae plus T. viride (0.444 ± 2.62) in roots and (0.437 ± 4.71) in shoots. Phosphorus content in roots was more than that in shoots. Chlorophyll content and stomatal conductivity also showed similar trend. 相似文献
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An estimator of relative risk in a case control study has been proposed in terms of observed cell frequencies and the probability of disease. The bias of the usual estimator i.e odds ratio as compared to the new estimator has been workedout. The expression of Mean Square Error of proposed estimator has been derived in situations where probability of disease is exactly known and when it is estimated through an independent survey. It has been observed that there is a serious error using odds ratio as an estimate of relative risk when probability of disease is not negligible. In such situations the proposed estimator can be used with advantage. 相似文献
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Srijan Aggarwal 《Biofouling》2013,29(4):479-486
Recently, a micro-cantilever method was introduced for measuring the ultimate tensile strength of intact bacterial biofilms. Herein, is reported the analysis of the video files from the testing of a 4-day-old Staphylococcus epidermidis biofilm to determine the elastic modulus, toughness, and failure strain. Elastic modulus (1270±280 Pa) was within the range of previously reported values (17–6000 Pa). The high failure strains (240±16%) indicate the substantial ductility of bacterial biofilms. In addition, the toughness of the biofilm sample was determined from the area under the stress–strain plot (2.8±0.44 kJ m?3). Thus, it was demonstrated that the micro-cantilever test video files can be used for the determination of other mechanical property parameters besides ultimate tensile strength. 相似文献