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71.
Anagha Chawhan Ashish Athale Khalid Khan Saurabh Agarwal Rajdeep Paul Karthik Iyer Anjali Khadia Vivek Som 《Indian journal of ophthalmology》2021,69(12):3633
Purpose:To evaluate the presence of SARS-CoV-2 RNA in the conjunctival swab sample of positive confirmed COVID-19 patients and to find out its association with comorbidity and severity of COVID-19 disease.Methods:We conducted an observational cross-sectional study at a dedicated tertiary COVID-19 hospital in central India for a period of 8 weeks from February 2021to March 2021. We included patients who tested positive for SARS-CoV-2 RNA through nasopharyngeal swab and were above 18 years of age. Swab samples have been collected within 48 h of admission. Conjunctival swab was taken from the lower fornix of both eyes and sent to microbiology laboratory for real-time- polymerase chain reaction (RT-PCR).Results:Out of 150 patients, conjunctival swab RT-PCR was positive in five patients (3.33%). Two patients had conjunctival manifestations in the form of conjunctivitis but conjunctival swab RT-PCR was negative in those patients. Among the RT-PCR positive patients, two (40%) were from mild, one (20%) was from moderate, and two (40%) were from severe category. No association could be established between conjunctival swab RT-PCR positivity and severity of the disease or associated comorbidity.Conclusion:Our study provides evidence that SARS-CoV-2 RNA could be detected in conjunctival secretions, and though the risk is relatively low, the eye may act as source of transmission. Extra caution should be taken by healthcare workers, and use of proper precautions like face shields and goggles should be encouraged. 相似文献
72.
Manan H Desai Laura J Olivieri Karthik V Ramakrishnan Tacy E Downing 《Interactive Cardiovascular and Thoracic Surgery》2021,32(4):658
An 8-year-old with a known diagnosis of an asymptomatic coronary artery fistula (CAF) presented with exertional syncope and haemopericardium due to contained rupture of CAF. A transcatheter closure was attempted, but the fistula ruptured again prompting emergency surgical repair. Spontaneous rupture is a catastrophic complication of CAF and warrants a high index of suspicion, timely diagnosis and team management. 相似文献
73.
Yasmeen M. Byrnes Neil N. Luu Ariel S. Frost Tiffany N. Chao Robert M. Brody Steven B. Cannady Karthik Rajasekaran Rabie M. Shanti Jason G. Newman 《世界耳鼻咽喉头颈外科杂志(英文)》2022,8(4):302
ObjectiveTo evaluate medical student and attending surgeon experiences with a novel interactive virtual Otolaryngology ‐ Head and Neck Surgery (OHNS) medical student elective during the COVID‐19 pandemic.Study DesignA virtual OHNS elective was created, with three components: (1) interactive virtual operating room (OR) experience using live‐stream video‐conferencing, (2) telehealth clinic, (3) virtual didactics.SettingOHNS Department at the University of Pennsylvania (May 2020 to June 2020).MethodsSix medical students from the University of Pennsylvania; five attending otolaryngologists. Two surveys were designed and distributed to participating medical students and attending surgeons. Surveys included 5‐point Likert scale items, with 1 indicating “not at all” and 5 indicating “very much so”.ResultsResponse rate was 100% for both surveys. Students on average rated the educational value of the telehealth experience as 4.2 ± 1.2, and the virtual OR experience as 4.0 ± 0.6. Most students (n = 5, 83%) indicated that they had enough exposure to faculty they met on this rotation to ask for a letter of recommendation (LOR) for residency if needed, while attending surgeons had an average response of 3.0 ± 1.0 when asked how comfortable they would feel writing a LOR for a student they met through the rotation. A majority of students (n = 4, 67%) felt they connected enough with faculty during the rotation to ask for mentorship. Half the students (n = 5, 50%) indicated that the rotation allowed them to evaluate the department''s culture either “extremely well” or “somewhat well”.ConclusionsOverall, participating students described this innovative virtual surgical rotation as an educationally and professionally valuable experience. With the continued suspension of visiting student rotations due to the COVID‐19 pandemic, this virtual model may have continued relevance to medical education. 相似文献
74.
A novel diamine bis(4-aminophenyl)bis{3,4[(4-(8-quinolyloxymethyl carbonyl)]}methane, containing two long/bulky aromatic pendent chains was synthesized by incorporating aromatic and hetero aromatic groups with flexible linkages. Flexible, stretchable, thermally stable and processable polyimides were prepared by reacting this newly synthesized diamine with commercial tetracarboxylic acid dianhydrides like 3,3′,4,4′-benzophenone tetra carboxylic acid dianhydride (BTDA) and 4,4′-(4,4′-isopropylidenediphenoxy)diphthalic Anhydride (BPADA). Nanocomposites of polyimides were prepared using aromatic amine functionalized silica as a filler by solution casting method. The current work investigates the effects of incorporating long/bulky aromatic side chains and flexible linkages on the thermal, mechanical, electrical and optical properties of the polyimides and nanocomposites. The polyimides showed good thermal stability (T10% = 364 & 388), high flame resistance, low glass transition temperatures (Tg = 130 °C & 156 °C), very low dielectric constants (2.5 & 2.8 at 1 MHz) and good optical transparency. The neat polyimides displayed good elongation at break (133–155%) but possessed low tensile strength. The chemically imidized polyimides showed good solubility in low and high boiling solvents. Nanocomposites of polyimides based on aromatic amine functionalized silica exhibited enhanced properties with T10% values varying between 409–482 °C, Tg between 165–280 °C and higher dielectric constants (3–5.7 at 1 MHz).Novel polyimides containing two long/bulky aromatic pendent chains and their nanocomposites with aromatic amine functionalized silica were prepared from a new diamine bis(4-aminophenyl)bis{3,4[(4-(8-quinolyloxymethyl carbonyl)phenoxy)]}methane. 相似文献
75.
76.
Ryan M. Carey Derek B. McMahon Zoey A. Miller TaeBeom Kim Karthik Rajasekaran Indiwari Gopallawa Jason G. Newman Devraj Basu Kevin T. Nead Elizabeth A. White Robert J. Lee 《Molecular oncology》2022,16(7):1474
Better management of head and neck squamous cell carcinomas (HNSCCs) requires a clearer understanding of tumor biology and disease risk. Bitter taste receptors (T2Rs) have been studied in several cancers, including thyroid, salivary, and GI, but their role in HNSCC has not been explored. We found that HNSCC patient samples and cell lines expressed functional T2Rs on both the cell and nuclear membranes. Bitter compounds, including bacterial metabolites, activated T2R‐mediated nuclear Ca2+ responses leading to mitochondrial depolarization, caspase activation, and ultimately apoptosis. Buffering nuclear Ca2+ elevation blocked caspase activation. Furthermore, increased expression of T2Rs in HNSCCs from The Cancer Genome Atlas is associated with improved overall survival. This work suggests that T2Rs are potential biomarkers to predict outcomes and guide treatment selection, may be leveraged as therapeutic targets to stimulate tumor apoptosis, and may mediate tumor‐microbiome crosstalk in HNSCC. 相似文献
77.
78.
The PtdIns 3-Kinase/Akt Pathway Regulates Macrophage-Mediated ADCC against B Cell Lymphoma
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Trupti Joshi Latha P. Ganesan Carolyn Cheney Michael C. Ostrowski Natarajan Muthusamy John C. Byrd Susheela Tridandapani 《PLoS Clinical Trials》2009,4(1)
Macrophages are important effectors in the clearance of antibody-coated tumor cells. However, the signaling pathways that regulate macrophage-induced ADCC are poorly defined. To understand the regulation of macrophage-mediated ADCC, we used human B cell lymphoma coated with Rituximab as the tumor target and murine macrophages primed with IFNγ as the effectors. Our data demonstrate that the PtdIns 3-kinase/Akt pathway is activated during macrophage-induced ADCC and that the inhibition of PtdIns 3-kinase results in the inhibition of macrophage-mediated cytotoxicity. Interestingly, downstream of PtdIns 3-kinase, expression of constitutively active Akt (Myr-Akt) in macrophages significantly enhanced their ability to mediate ADCC. Further analysis revealed that in this model, macrophage-mediated ADCC is dependent upon the release of nitric oxide (NO). However, the PtdIns 3-kinase/Akt pathway does not appear to regulate NO production. An examination of the role of the PtdIns 3-kinase/Akt pathway in regulating conjugate formation indicated that macrophages treated with an inhibitor of PtdIns 3-kinase fail to polarize the cytoskeleton at the synapse and show a significant reduction in the number of conjugates formed with tumor targets. Further, inhibition of PtdIns 3-kinase also reduced macrophage spreading on Rituximab-coated surfaces. On the other hand, Myr-Akt expressing macrophages displayed a significantly greater ability to form conjugates with tumor cells. Taken together, these findings illustrate that the PtdIns 3-kinase/Akt pathway plays a critical role in macrophage ADCC through its influence on conjugate formation between macrophages and antibody-coated tumor cells. 相似文献
79.
Karthik S. Suresh R. Jeannie Roberts Rif S. El-Mallakh 《The Psychiatric quarterly》2013,84(3):337-341
The Mood Disorders Questionnaire (MDQ) is a tool that was created for screening for bipolar disorders. This study investigates the utility of the MDQ in an acute psychiatric in-patient setting. All patients admitted to an acute inpatient psychiatric unit completed the MDQ. Discharge diagnoses strictly followed DSM-IV criteria, but were determined through clinical interviews, collateral information, and psychiatric history, and were used to calculate the sensitivity and specificity of the MDQ in this setting. 44 subjects were admitted during the study period; 42 completed the MDQ. 12 had bipolar illness. Sensitivity of MDQ was 0.58, and specificity was 0.76 (P < 0.05). Positive predictive value was 0.50 and negative predictive value was 0.82. The specificity and sensitivity of the MDQ appears to vary with the illness severity of the patients screened. 相似文献
80.