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21.
G P Thomas M Karmazyn A C Zygmunt C Antzelevitch N Narayanan 《British journal of pharmacology》1999,126(7):1531-1533
The antimycotic agent clotrimazole (CLT) is a promising potential therapeutic agent for a variety of diseases including cancer. Although it is known that CLT alters calcium homeostasis in many cell types, its cardiac effects are virtually unknown. We investigated the effects of CLT on L-type calcium current (ICa,L) and action potentials in guinea-pig ventricular myocytes. CLT (5, 25 and 50 microM) inhibited basal ICa,L by 16, 59 and 93%, respectively. The inhibitory effect of CLT was rapid and the peak effect was attained within 3 min. At a concentration of 25 microM, the inhibitory effect of CLT was partially reversible whereas the response to 50 microM CLT persisted following drug withdrawal. CLT abbreviated action potential duration at 50 and 90% of repolarization and suppressed the plateau significantly. These results indicate that CLT may have important cardiac effects at concentrations used to induce the antiproliferative action of the drug. 相似文献
22.
Marc D. Liang M.D. Krishna Narayanan M.D. Peter L. Davis M.D. J. William Futrell M.D. 《Aesthetic plastic surgery》1991,15(1):313-319
Magnetic resonance imaging (MRI) provides noninvasive images of facial and neck fat for a variety of conditions. It accurately maps the soft tissues pre- and postoperatively, enabling surgeons to precisely and objectively assess results of soft tissue facial contouring and fat transplantation. The risks of MRI are few. It has the potential to provide aesthetic surgeons with a more scientific means of comparing various techniques of fat contouring. 相似文献
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Mi ZP Jiang P Weng WL Lindberg FP Narayanan V Lagenaur CF 《The Journal of comparative neurology》2000,416(3):335-344
P84 and integrin associated protein (IAP) are heterophilic binding partners that are expressed in the central nervous system in addition to a variety of other tissues. Both molecules are known to be involved in cell signaling in nonneural tissues. In the retina, both molecules are expressed prominently in plexiform layers, suggesting a possible association with synapses. Here, we examined the cellular expression and ultrastructural localization of the two molecules in the developing mouse retina. Both appeared to be expressed at one or both sides of synaptic sites, although the expression of IAP in the retina precedes that of P84. Examination of transgenic IAP-null retinae revealed a failure of P84 to become associated with synaptic sites, suggesting the interaction of P84 with IAP was necessary for P84's synaptic localization. These findings suggest that the signaling activities of P84 and IAP are localized to sites of synaptic contact in the retina. Thus this pair of synapse-associated molecules represents a bidirectional signaling system that could function to modify synaptic activity or possibly trophic interactions between central neurons. 相似文献
25.
Akash Belenje Brijesh Takkar Komal Agarwal Mudit Tyagi Vinod Aggarwal Tapas R Padhi Raja Narayanan 《Indian journal of ophthalmology》2022,70(3):902
Purpose:To evaluate the causes of jet stream injury (JSI)-related iatrogenic retinal breaks (IRBs) during vitreoretinal surgery (VRS).Methods:The precise surgical environment, which includes the indication and type of surgical procedure, retina status, details of instrumentation and fluidic parameters, and characteristics of the jet responsible for the IRB, was noted from case records. The nature of IRB and its healing and impact on anatomical and visual outcomes were analyzed.Results:Five eyes of five patients with complete documentation of both the JSI and the IRB were included. Two cases were operated for macular hole, and one each for vitreous hemorrhage, retinal detachment, and endophthalmitis. One case had infusion-fluid-related JSI, while four developed it because of injection of surgical adjuncts (drugs, PFCL, and dye). JSI developed in two cases when the vitreous cavity was filled with fluid, while it was air-filled in three cases. In four cases, the fluid migrated into subretinal space, necessitating further maneuvers following which the breaks healed, but were directly responsible for vision loss in two cases.Conclusion:JSI related IRBs are rare but may be directly responsible for vision loss if they impact the macula. The balance between jet stream velocity, its distance from the retinal surface, the intervening media (vitreous cavity), and retinal health play an important role. It can occur because of both infusion as well as injection jets. Precautions must be taken in cases vulnerable to complications with suggested modifications in the surgical technique. 相似文献
26.
OBJECTIVE: To determine whether vestibulectomy is an effective long-term treatment and investigate the levels of patient satisfaction in women with localized provoked vulvodynia, and to provide long-term follow-up data from a cohort of women whose short-term success rates have been published previously. STUDY DESIGN: A retrospective case note review of 110 women with localized provoked vulvodynia and follow-up patient questionnaire. Patients were asked to quantify their pain scores before surgery, at 2 months after surgery and 1 year after surgery and score their satisfaction levels. RESULTS: Mean pain scores continued to improve throughout the first postoperative year. The mean score was 9.17 preoperatively, 5.24 at 2 months after surgery and 2.48 at 1 year after surgery. Eighty-three percent of patients would recommend the procedure as effective treatment of localized provoked vulvodynia. The overall mean satisfaction score was 7.96, and long-term success appears to be reflected by short-term results. CONCLUSION: Vestibulectomy is an effective long-term treatment for women with provoked localized vulvodynia; the procedure is associated with high levels of patient satisfaction and low complication rates. Shortterm success appears to be a good indicator of long-term improvement, and improve- ment continues throughout the first postoperative year. 相似文献
27.
Sumana G Dadhwal V Deka D Mittal S 《The journal of obstetrics and gynaecology research》2008,34(5):801-804
OBJECTIVE: Non-cirrhotic portal hypertension (NCPH) is a common cause of portal hypertension in developing countries, especially Asia. Recent data have shown near-normal reproductive function and good pregnancy outcome for NCPH compared with cirrhosis. The aim of the present study was to evaluate complications during pregnancy and pregnancy outcome in women with NCPH. METHODS: Twelve pregnancies in five patients with NCPH were evaluated. RESULTS: In the present study, 20% of patients had hematemesis during pregnancy that was managed successfully. Four patients (80%) had severe anemia (hemoglobin 6-7 g%) and three (60%) had thrombocytopenia. There were no preterm births. Of a total of nine live births, six were vaginal deliveries and three were delivered by Cesarean section (performed for obstetric indications). Four babies (44%) were small for gestational age (SGA). CONCLUSIONS: The results show that patients with NCPH have normal fertility, no apparent increase in the incidence of hematemesis during pregnancy, an increased incidence of SGA babies and no indication for elective Cesarean delivery. 相似文献
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Miruthula Tamil Selvan Sachithra Gunasekara Ping Xiao Kristen Griffin Shannon R. Cowan Sai Narayanan Akhilesh Ramachandran Darren E. Hagen Jerry W. Ritchey Jennifer M. Rudd Craig A. Miller 《Viruses》2022,14(6)
Continued emergence of SARS-CoV-2 variants highlights the critical need for adaptable and translational animal models for acute COVID-19. Limitations to current animal models for SARS CoV-2 (e.g., transgenic mice, non-human primates, ferrets) include subclinical to mild lower respiratory disease, divergence from clinical COVID-19 disease course, and/or the need for host genetic modifications to permit infection. We therefore established a feline model to study COVID-19 disease progression and utilized this model to evaluate infection kinetics and immunopathology of the rapidly circulating Delta variant (B.1.617.2) of SARS-CoV-2. In this study, specific-pathogen-free domestic cats (n = 24) were inoculated intranasally and/or intratracheally with SARS CoV-2 (B.1.617.2). Infected cats developed severe clinical respiratory disease and pulmonary lesions at 4- and 12-days post-infection (dpi), even at 1/10 the dose of previously studied wild-type SARS-CoV-2. Infectious virus was isolated from nasal secretions of delta-variant infected cats in high amounts at multiple timepoints, and viral antigen was co-localized in ACE2-expressing cells of the lungs (pneumocytes, vascular endothelium, peribronchial glandular epithelium) and strongly associated with severe pulmonary inflammation and vasculitis that were more pronounced than in wild-type SARS-CoV-2 infection. RNA sequencing of infected feline lung tissues identified upregulation of multiple gene pathways associated with cytokine receptor interactions, chemokine signaling, and viral protein–cytokine interactions during acute infection with SARS-CoV-2. Weighted correlation network analysis (WGCNA) of differentially expressed genes identified several distinct clusters of dysregulated hub genes that are significantly correlated with both clinical signs and lesions during acute infection. Collectively, the results of these studies help to delineate the role of domestic cats in disease transmission and response to variant emergence, establish a flexible translational model to develop strategies to prevent the spread of SARS-CoV-2, and identify potential targets for downstream therapeutic development. 相似文献
30.
Emily J. Aston Michael G. Wallach Aarthi Narayanan Sofia Egaa-Labrin Rodrigo A. Gallardo 《Viruses》2022,14(7)
The novel severe acute respiratory syndrome (SARS) coronavirus, SARS-CoV-2, is responsible for the global COVID-19 pandemic. Effective interventions are urgently needed to mitigate the effects of COVID-19 and likely require multiple strategies. Egg-extracted antibody therapies are a low-cost and scalable strategy to protect at-risk individuals from SARS-CoV-2 infection. Commercial laying hens were hyperimmunized against the SARS-CoV-2 S1 protein using three different S1 recombinant proteins and three different doses. Sera and egg yolk were collected at three and six weeks after the second immunization for enzyme-linked immunosorbent assay and plaque-reduction neutralization assay to determine antigen-specific antibody titers and neutralizing antibody titers, respectively. In this study we demonstrate that hens hyperimmunized against the SARS-CoV-2 recombinant S1 and receptor binding domain (RBD) proteins produced neutralizing antibodies against SARS-CoV-2. We further demonstrate that antibody production was dependent on the dose and type of antigen administered. Our data suggests that antibodies purified from the egg yolk of hyperimmunized hens can be used as immunoprophylaxis in humans at risk of exposure to SARS-CoV-2. 相似文献