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61.
Our major theme is that the layered structure of the endothelial barrier requires continuous activation of signalling pathways regulated by sphingosine‐1‐phosphate (S1P) and intracellular cAMP. These pathways modulate the adherens junction, continuity of tight junction strands, and the balance of synthesis and degradation of glycocalyx components. We evaluate recent evidence that baseline permeability is maintained by constant activity of mechanisms involving the small GTPases Rap1 and Rac1. In the basal state, the barrier is compromised when activities of the small GTPases are reduced by low S1P supply or delivery. With inflammatory stimulus, increased permeability can be understood in part as the action of signalling to reduce Rap1 and Rac1 activation. With the hypothesis that microvessel permeability and selectivity under both normal and inflammatory conditions are regulated by mechanisms that are continuously active, it follows that when S1P or intracellular cAMP are elevated at the time of inflammatory stimulus, they can buffer changes induced by inflammatory agents and maintain normal barrier stability. When endothelium is exposed to inflammatory conditions and subsequently exposed to elevated S1P or intracellular cAMP, the same processes restore the functional barrier by first re‐establishing the adherens junction, then modulating tight junctions and glycocalyx. In more extreme inflammatory conditions, loss of the inhibitory actions of Rac1‐dependent mechanisms may promote expression of more inflammatory endothelial phenotypes by contributing to the up‐regulation of RhoA‐dependent contractile mechanisms and the sustained loss of surface glycocalyx allowing access of inflammatory cells to the endothelium. 相似文献
62.
K Kiran Kumar UC Sampritha Akshata A Prakash Karishma Adappa S Chandraprabha TG Neeraja N S Guru Prasad Jessica Basumatary Suresh Babu Gangasagara B L Sujatha Rathod Chakravarthy Raghunathan Jayanthi 《Indian journal of ophthalmology》2021,69(3):691
Purpose:The aim of this study was to determine the frequency and various types of ophthalmic manifestation of patients with COVID-19.Methods:This is a prospective observational study conducted on patients with SARS-Co-V-2 infection, at a dedicated tertiary COVID-19 hospital in South India from April 1 to July 31, 2020. At the time of their admission to the COVID hospital, demographic data such as name, age, sex was recorded. A thorough history regarding the onset, duration, progression, nature of symptoms and its associated factors, medication history, treatment history were elicited and documented. Ocular examination was performed under torchlight by an ophthalmologist posted for COVID duty. Further investigations including imaging were sought for, depending on clinical indications. Serial follow-up examinations of all patients were carried out every 72 hours or when patients complained of any ocular symptoms whichever earlier, until discharge. All relevant data were compiled and statistically analyzed.Results:A total of 2742 patients were examined. Of them, 1461 (53.28%) were males and 1281 (46.72%) were females. The mean age (±SD) was 39.46 ± 17.63 years. None of the patients in our study had any ocular symptoms or signs as the presenting complaint at the time of their admission. On subsequent follow-up, only 20 (0.72%) developed ocular manifestations, of which 19 (95%) had features suggestive of Bilateral viral conjunctivitis. However, 1 (5%) patient had orbital cellulitis secondary to pansinusitis.Conclusion:Ophthalmic manifestations in the clinical spectrum of COVID-19 infection are uncommon and unlikely to be the presenting clinical impression. However, it has broadened our view to a wider spectrum of COVID-19 presentations enhancing our clinical acumen for staunch detection of COVID-19 suspects in our daily practice, augmenting early diagnosis and management and also break the chain of transmission for the greater good of humanity. 相似文献
63.
Cherie Paquette Mark F. Evans Shabnum S. Meer Vanitha Rajendran Christine S-C. Adamson Kumarasen Cooper 《Head and neck pathology》2013,7(4):361-372
Human papillomavirus (HPV) infection, most commonly genotype 16 of the alpha-9 family, is implicated in the etiology of a subset of oropharyngeal squamous cell carcinomas (OPSC) worldwide. Data are scarce regarding OPSC in South Africans, and three prior studies suggest no significant etiologic role for HPV. We aimed to investigate for evidence of HPV etiology in OPSCs from black South Africans by polymerase chain reaction (PCR) methodologies with determination of HPV subtype by sequencing, in situ hybridization (ISH), and p16INK4a immunohistochemistry (IHC), as a surrogate marker for an HPV-driven tumor. It was hypothesized that HPV-driven tumors would be positive by PCR plus IHC and/or ISH whereas OPSCs with HPV background infections (HPV-passenger) would be positive by PCR alone. Formalin-fixed, paraffin-embedded tissues from 51 OPSCs collected between 2005 and 2010 from 41 patients were analyzed for HPV by GP5+6+ PCR (targeting the HPV L1 region), pU-1M/pU-2R PCR (targeting the HPV E6/E7 region) and HPV-31 specific PCR (targeting the E5 region), chromogenic ISH, and p16INK4a IHC. All cases positive by PCR were subject to sequencing to determine HPV genotype. The patient mean age was 58.0 years and 88 % were male. Of the 51 evaluable tumors, 48 (94.1 %) were positive for HPV DNA by PCR: 25 (49.1 %) met criteria for an HPV-driven tumor, 23 (45.1 %) for HPV-passenger, and 3 (5.9 %) were HPV-unrelated. Sequencing of the PCR-positive cases revealed the following genotypes: combined HPV-16 and 31 (41.7 %), HPV-31 (25.0 %), HPV-16 (22.9 %), combined HPV-16 and 18 (6.3 %), and a single case each of HPV 18 and HPV 33. Studies via ISH were negative in all cases. In accordance with worldwide trends but contrary to prior South African data, HPV likely plays an etiologic role in a significant subset (at least 49.1 %) of OPSC in black South Africans. We found that the alpha-9 HPV family, particularly HPV-16 and 31 either in combination or separately, to predominate in our sample tumors. The use of multiple PCR primers increased sensitivity of viral detection, and a HPV-31 specific primer confirmed the presence of this genotype in many samples. Further studies including HPV E6/E7 mRNA assays are needed to better elucidate the pathogenic role of HPV in black South African OPSCs. 相似文献
64.
65.
Ranjith Babu Peter G. Kranz Isaac O. Karikari Allan H. Friedman Cory Adamson 《Journal of clinical neuroscience》2013,20(10):1382-1386
Adult brainstem gliomas (BSG) are uncommon tumors that constitute only 2% of all brain tumors. Due to its rare occurrence in the elderly (60 years and older), there is no literature discussing the natural history, prognosis, and best treatment strategy for malignant BSG in this population to our knowledge. We report seven elderly patients with malignant BSG and propose treatment strategies to manage these aggressive tumors. The median age at onset in this cohort was 65 years, with the majority of patients being male (71.4%) and Caucasian (85.7%). The median duration of symptoms prior to presentation was 0.5 months, with the most common symptoms being facial weakness, blurry vision, headache, and extremity weakness. Tumors were most commonly located in the pons (85.7%), with one tumor being located in the tectal plate. Five of seven (71.4%) patients underwent biopsies, with two patients undergoing partial resections. Following tissue diagnosis, patients received radiation therapy and concurrent temozolomide, followed by additional chemotherapeutics upon progression. Side effects as a result of treatment were seen in three patients and all involved reversible hematological complications such as neutropenia and thrombopenia. The median time to progression was 6.7 months and the median overall survival was 13.5 months. While malignant BSG in elderly patients are aggressive gliomas with an overall poor prognosis, these patients are able to safely undergo aggressive chemoradiotherapy, resulting in improved survival. Resection may be considered for select patients in which the tumor is mostly exophytic, near the brainstem surface, and easily accessible. 相似文献
66.
Salomone Erica Settanni Michele McConachie Helen Suma Katharine Ferrara Federica Foletti Giulia Salandin Arianna Servili Chiara Adamson Lauren B. 《Journal of autism and developmental disorders》2022,52(10):4286-4300
Journal of Autism and Developmental Disorders - Parents of children with ASD (N?=?86; mean age 44.8 months; 67 boys) were randomized to either WHO Caregiver Skills Training... 相似文献
67.
68.
Nuno?Mendon?aEmail authorView authors OrcID profile Antoneta?Granic John?C.?Mathers Tom?R.?Hill Mario?Siervo Ashley?J.?Adamson Carol?Jagger 《European journal of nutrition》2018,57(8):2713-2722
Purpose
The very old (aged ≥ 85 years), fastest growing age group in most western societies, are at especially high risk of muscle mass and strength loss. The amount, sources and timing of protein intake may play important roles in the aetiology and management of sarcopenia. This study investigated the prevalence and determinants of low protein intake in 722 very old adults participating in the Newcastle 85+ Study.Methods
Protein intake was estimated with 2 × 24-h multiple pass recalls (24 h-MPR) and contribution (%) of food groups to protein intake was calculated. Low protein intake was defined as intake < 0.8 g of protein per adjusted body weight per day. A backward stepwise multivariate linear regression model was used to explore socioeconomic, health and lifestyle predictors of protein intake.Results
Twenty-eight percent (n = 199) of the community-living very old in the Newcastle 85+ Study had low protein intake. Low protein intake was less likely when participants had a higher percent contribution of meat and meat products to total protein intake (OR 0.97, 95% CI 0.95, 1.00) but more likely with a higher percent contribution of cereal and cereal products and non-alcoholic beverages. Morning eating occasions contributed more to total protein intake in the low than in the adequate protein intake group (p < 0.001). Being a woman (p < 0.001), having higher energy intake (p < 0.001) and higher tooth count (p = 0.047) was associated with higher protein intake in adjusted models.Conclusion
This study provides novel evidence on the prevalence of low protein intake, diurnal protein intake patterns and food group contributors to protein intake in the very old.69.
70.