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41.

The ongoing SARS-CoV-2 evolution process has generated several variants due to its continuous mutations, making pandemics more critical. The present study illustrates SARS-CoV-2 evolution and its emerging mutations in five directions. First, the significant mutations in the genome and S-glycoprotein were analyzed in different variants. Three linear models were developed with the regression line to depict the mutational load for S-glycoprotein, total genome excluding S-glycoprotein, and whole genome. Second, the continent-wide evolution of SARS-CoV-2 and its variants with their clades and divergence were evaluated. It showed the region-wise evolution of the SARS-CoV-2 variants and their clustering event. The major clades for each variant were identified. One example is clade 21K, a major clade of the Omicron variant. Third, lineage dynamics and comparison between SARS-CoV-2 lineages across different countries are also illustrated, demonstrating dominant variants in various countries over time. Fourth, gene-wise mutation patterns and genetic variability of SARS-CoV-2 variants across various countries are illustrated. High mutation patterns were found in the ORF10, ORF6, S, and low mutation pattern E genes. Finally, emerging AA point mutations (T478K, L452R, N501Y, S477N, E484A, Q498R, and Y505H), their frequencies, and country-wise occurrence were identified, and the highest event of two mutations (T478K and L452R) was observed.

  相似文献   
42.
43.
Fungal pathogens causing leaf blight of Ocimum sanctum L. have been isolated from the lateritic belt of Birbhum district of West Bengal, India and were identified as species of Alternaria. The pathogen not only destroys the mesophyll tissues of the leaves but also decreases the antibacterial potential and antioxidant activity of Ocimum plants. Two strains of Lactococcus lactis subsp. hordniae, viz., LABW1, LABW3 and a strain of Lactococcus lactis subsp. lactis LABW4, isolated from high quality fermented milk product (homemade buttermilk), were able to produce significant zones of inhibition against the pathogen on dual culture overlay plates. A maximum of 4.5 ± 0.2 cm zone of inhibition was produced by LABW4. Cell free supernatant of LABW4 (50%) was also effective to inhibit more than 89% of conidial germination of Alternaria sp. VBOS17. Antifungal action of LABW4 was responsible for prominent mycelial deformations and breakages of pathogen as evident from scanning electron microscopic studies. During in vivo greenhouse experiment only 14.57 ± 1.99% leaf blight was noticed after 60 days of bacterial application even upon treatment with high concentration of Alternaria conidia (1.6 × 104 conidia/ml), as compared to pathogen treated set (87.95 ± 2.14%). Efficacy of LABW4 to control the disease was also noticed during field experiment. In addition, LABW4 also increased the antibacterial and antioxidant potentials of the plant. L. lactis subsp. lactis LABW4 can be used as a prospective agent to control leaf blight disease of Ocimum plant and to increase its medicinal properties.  相似文献   
44.

Purpose

Visual performance following toric intraocular lens implantation for cataract with moderate and severe astigmatism.

Setting

Cataract services, Shroff Eye Centre, New Delhi, India.

Design

Case series.

Method

This prospective study included 64 eyes of 40 patients with more than 1.50 dioptre (D) of pre-existing corneal astigmatism undergoing phacoemulsification with implantation of the AcrySof® toric IntraOcular Lens (IOL). The unaided visual acuity (UCVA), best corrected visual acuity (BCVA), residual refractive sphere and refractive cylinders were evaluated. Toric IOL axis and alignment error was measured by slit lamp method and Adobe Photoshop (version 7) method. Patient satisfaction was evaluated using a satisfaction questionnaire at 3 months.

Results

The mean residual refractive astigmatism was 0.57 D at the final follow-up of 3 months. Mean alignment error was 3.44 degrees (SD = 2.60) by slit lamp method and 3.88 degrees (SD = 2.86) by Photoshop method. Forty-six (71.9%) eyes showed misalignment of 5 degrees or less, and 60 (93.8%) eyes showed misalignment of 10 degrees or less. The mean log MAR UCVA at 1st post-op day was 0.172 (SD = 0.02), on 7th post-op day was 0.138 (SD = 0.11), and on 30th post-op day was 0.081 (SD = 0.11). The mean log MAR BCVA at three months was −0.04 (SD = 0.76).

Conclusion

We believe that implantation of AcrySof® toric IOL is an effective, safe and predictable method to correct high amounts of corneal astigmatism during cataract surgery.  相似文献   
45.
Hepatitis E virus (HEV) is an important cause of repeated waterborne outbreaks of acute hepatitis. Recently, several extrahepatic manifestations (EHMs) have been described in patients with HEV infection. Of these, neurological disorders are the most common EHM associated with HEV. The involvement of both the peripheral nervous system and central nervous system can occur together or in isolation. Patients can present with normal liver function tests, which can often be misleading for physicians. There is a paucity of data on HEV-related neurological manifestations; and these data are mostly described as case reports and case series. In this review, we analyzed data of 163 reported cases of HEV-related neurological disorders. The mechanisms of pathogenesis, clinico-demographic profile, and outcomes of the HEV-related neurological disorders are described in this article. Nerve root and plexus disorder were found to be the most commonly reported disease, followed by meningoencephalitis.  相似文献   
46.
In the Indian state of Bihar, the sensitivities and specificities of direct agglutination tests (DAT) and rK39 test strips for the detection of Leishmania donovani infection in humans were explored and found to be generally good (92%-100%). When 172 asymptomatic individuals [16 'case-contacts' who lived in the same households as past or current, confirmed cases of visceral leishmaniasis (VL) and 156 other subjects from neighbouring households] were tested, the same 36 (21%) individuals, including all 16 'case-contacts', were found seropositive using each type of test. When followed-up after 3 months, 18 of the individuals who had been found seropositive in the baseline survey remained seropositive, and eight (44%) of these had developed symptomatic VL, with amastigotes in their splenic aspirates. Seven (44%) of the 16 'case-contacts' but only one (5%) of the other 20 subjects found seropositive at baseline went on to develop VL within 3 months. Although the strip test appeared slightly better than DAT for predicting the development of VL in the 172 subjects, either type of test may be very useful for the early detection of asymptomatic L. donovani infection and thus the identification of those at relatively high risk of developing VL.  相似文献   
47.
The optimal medium for cardiac differentiation of adult primitive cells remains to be established. We quantitatively compared the efficacy of IGF-1, dynorphin B, insulin, oxytocin, bFGF, and TGF-β1 in inducing cardiomyogenic differentiation. Adult mouse skeletal muscle-derived Sca1+/CD45-/c-kit-/Thy-1+ (SM+) and Sca1-/CD45-/c-kit-/Thy-1+ (SM-) cells were cultured in basic medium (BM; DMEM, FBS, IGF-1, dynorphin B) alone and BM supplemented with insulin, oxytocin, bFGF, or TGF-β1. Cardiac differentiation was evaluated by the expression of cardiac-specific markers at the mRNA (qRT-PCR) and protein (immunocytochemistry) levels. BM+TGF-β1 upregulated mRNA expression of Nkx2.5 and GATA-4 after 4 days and Myl2 after 9 days. After 30 days, BM+TGF-β1 induced the greatest extent of cardiac differentiation (by morphology and expression of cardiac markers) in SM- cells. We conclude that TGF-β1 enhances cardiomyogenic differentiation in skeletal muscle-derived adult primitive cells. This strategy may be utilized to induce cardiac differentiation as well as to examine the cardiomyogenic potential of adult tissue-derived stem/progenitor cells. Electronic supplementary material  The online version of this article (DOI:) contains supplementary material, which is available to authorized users. Returned for 1. Revision: 8 January 2008 1. Revision received: 8 April 2008 Ahmed Abdel-Latif and Ewa K. Zuba-Surma contributed equally to this work.  相似文献   
48.
Oxazines have brought much synthetic interest due to their extensive biological activities. These are the important category of heterocycles, which may be formally derived from benzene and its reduction products by convenient substitution of carbon (and hydrogen) atoms by nitrogen and oxygen. In the last few decades, oxazine derivatives have documented as worthy synthetic intermediates and also blessed with notable sedative, analgesic, anticonvulsant, antipyretic, antimicrobial, antitubercular, antimalarial, antioxidant, and anticancer activities. Nowadays, it is important to develop new classes of compounds with more effective mechanisms due to drug resistance activity in which the ability of drug to effectively treat disease can be reduced. The aim of the article is to collect and make a more generalized review on the synthesis of oxazine derivatives and their pharmaceutical and biological activities. We hope this review will provide ample references for the researchers concerned with azines in generally and oxazines in particular.  相似文献   
49.
A central venous catheter is the most common access for initiating hemodialysis. Prolonged access through a central venous catheter increases the risk of infection and dysfunction of the catheter with potential development of catheter-induced thrombosis and embolism. However, fracture and dislodgement of the catheter with subsequent embolization is an unexpected complication. Endovascular treatment is a promising method to remove intravascular foreign bodies. We herein report a case of a 58-year-old woman undergoing prolonged hemodialysis who required central venous catheter removal because of mechanical fracture of the tunneled cuffed catheter and its migration in the internal jugular vein. An urgent chest X-ray showed that the two free ends of the fractured tunneled cuffed catheter were located in the right atrium and right internal jugular vein. Phlebotomy of the internal jugular vein was successfully performed to retrieve the fractured tunneled cuffed catheter and the associated thrombi. In this case, phlebotomy for retrieval of the embolized catheter fragment extending into the right atrium was a safe alternative to an endovascular technique of catheter fragment retrieval. Phlebotomy preserved the integrity of the catheter fragment and its associated thrombus and was both cost-effective and safe.  相似文献   
50.

SUMMARY

This review article introduces the significance of testing of volatile organic compounds (VOCs) in clinical samples and summarizes important features of some of the technologies. Compared to other human diseases such as cancer, studies on VOC analysis in cases of infectious diseases are limited. Here, we have described results of studies which have used some of the appropriate technologies to evaluate VOC biomarkers and biomarker profiles associated with infections. The publications reviewed include important infections of the respiratory tract, gastrointestinal tract, urinary tract, and nasal cavity. The results highlight the use of VOC biomarker profiles resulting from certain infectious diseases in discriminating between infected and healthy subjects. Infection-related VOC profiles measured in exhaled breath as well as from headspaces of feces or urine samples are a source of information with respect to disease detection. The volatiles emitted in clinical matrices may on the one hand represent metabolites of the infecting pathogen or on the other hand reflect pathogen-induced host responses or, indeed, a combination of both. Because exhaled-breath samples are easy to collect and online instruments are commercially available, VOC analysis in exhaled breath appears to be a promising tool for noninvasive detection and monitoring of infectious diseases.  相似文献   
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