1,018 research outputs found
It Takes T to Tango
AbstractOf three recently cloned T-type voltage-gated calcium channels, α1g is most likely responsible for burst firing in thalamic relay cells. These neurons burst during various thalamocortical oscillations including absence seizures. In this issue of Neuron, Kim et al. inactivated α1g, and resultant mice were deficient in relay cell bursting and resistant to GABAB receptor-dependent absence seizures, suggesting roles for α1g and relay cell bursting in absences
The types, incidence and demographic distribution of benign oral and maxillofacial neoplasms among patients attending Muhimbili National Hospital in Tanzania, 2008-2013
Background: Pathological processes of oral and maxillofacial region are generally classified as benign or malignant based on specific histological criteria, including the presence or absence of necrosis, mitotic figures as well as basic understanding of the entity. The objective of this study was to determine the types, prevalence and demographic distribution of benign oral and maxillofacial tumours among patients treated at Muhimbili National Hospital in Tanzania.Methods: In this retrospective study, data on histological results of lesions of the oral and maxillofacial region were retrieved from the archives at the Department of Oral and Maxillofacial Surgery of Muhimbili National Hospital were analysed. The tumour type, age, sex, file number and histopathological diagnosis of the patient were recorded. The study covered a period of from January 2008 to December 2013. The top ten lesions with higher frequency of occurrence from January to were picked for analysis.Results: A total of 897 (males=388; females=509) histological results of patients with benign oral and maxillofacial lesions were obtained during the period under review. The age ranged from 0 to 88 years, mean age being 32.63 ± 17.1 while the age group of 20-29 and 30-39 were the most affected. A total of 136 different types of benign lesions were reported and ameloblastoma was the most common benign lesion (27.4%) followed by ossifying fibroma (18.7%), pyogenic granuloma (11.4%), pleomorphic adenoma (10.0%), and fibrous dysplasia (9.6%). Females were more affected than males, with a male to female ratio of 1:1.4 however the difference was statistically insignificant (p= 0.055).Conclusion: Ameloblastoma and ossifying fibroma were the most common oral and maxillo-facia neoplasms at Muhimbili National Hospital. The young age groups were the most affected by these lesions
Fine Structure of the Fibrillar Flight Muscles in the Housefly, Musca domestica (Diptera)
Insects of the orders Hemiptera, Hymenoptera, Coleoptera and Diptera have developed an asynchronous flight mechanism. The frequency of the muscle contraction is not directly related to the rate of nervous stimulation (Pringle 1965). An initial nervous stimulus produces an active state in the flight muscle during which a variable number of oscillatory contractions take place. Consequently, insects like the house-fly can maintain a very high frequency of wing beat (180-200 per second). Asynchronous flight muscles differ from the vertebrate skeletal muscles and insect synchronous flight muscles; in the latter each nerve impulse produces a single contraction of the innervated fibres. The asynchronous flight muscles are usually referred to as \u27 fibrillar muscles because of the easy dissociability of their large myofibrils. The existing information on the cytology of the fibrillar muscles is quite meagre as compared to the vertebrate striated muscles. The present report is concerned with the ultrastructural organization of the fibrillar flight muscles of the common house-fly, Musca domestica
A Novel Shared Protection Scheme Based on Aggregate Wavelength in High Speed Networks
We propose novel analytical model of dynamic link cost evaluation in IP over WDM networks. We suggest disjoint path algorithm for the primary and backup path based on wavelength aggregate information, to provide shared backup. We show the optimality of pair selected because of joint optimization of the pair paths. The shareable capacity factor is introduced to establish the effect of load balancing on resources. We compared our simulation results with that of separate protection at connection and showed improvement on resource utilization performance of the network. We also study the blocking probability of proposed scheme
The main rhinovirus respiratory tract adhesion site (ICAM-1) is upregulated in smokers and patients with chronic airflow limitation (CAL).
BACKGROUND: ICAM-1 is a major receptor for ~60% of human rhinoviruses, and non-typeable Haemophilus influenzae, two major pathogens in COPD. Increased cell-surface expression of ICAM-1 in response to tobacco smoke exposure has been suggested. We have investigated epithelial ICAM-1 expression in both the large and small airways, and lung parenchyma in smoking-related chronic airflow limitation (CAL) patients. METHODS: We evaluated epithelial ICAM-1 expression in resected lung tissue: 8 smokers with normal spirometry (NLFS); 29 CAL patients (10 small-airway disease; 9 COPD-smokers; 10 COPD ex-smokers); Controls (NC): 15 normal airway/lung tissues. Immunostaining with anti-ICAM-1 monoclonal antibody was quantified with computerized image analysis. The percent and type of cells expressing ICAM-1 in large and small airway epithelium and parenchyma were enumerated, plus percentage of epithelial goblet and submucosal glands positive for ICAM- 1. RESULTS: A major increase in ICAM-1 expression in epithelial cells was found in both large (p < 0.006) and small airways (p < 0.004) of CAL subjects compared to NC, with NLFS being intermediate. In the CAL group, both basal and luminal areas stained heavily for ICAM-1, so did goblet cells and sub-mucosal glands, however in either NC or NLFS subjects, only epithelial cell luminal surfaces stained. ICAM-1 expression on alveolar pneumocytes (mainly type II) was slightly increased in CAL and NLFS (p < 0.01). Pack-years of smoking correlated with ICAM-1 expression (r = 0.49; p < 0.03). CONCLUSION: Airway ICAM-1 expression is markedly upregulated in CAL group, which could be crucial in rhinoviral and NTHi infections. The parenchymal ICAM-1 is affected by smoking, with no further enhancement in CAL subjects
Correlation between vitamin A, E, coenzyme Q10 and degree of insulin resistance in obese and non-obese subjects
The aim of the present study was to investigate correlation between plasma vitamin A, vitamin E, serum coenzyme Q10 levels and degree of insulin resistance in obese and normal weight people. The study was performed on 98 (21 Male, 77 Female) obese people and 78 (20 Male, 58 Female) control subjects. Vitamin A, E and coenzyme Q10 levels were adjusted to the lipid levels. Adjusted vitamin A and E and coenzyme Q10 levels of the obese female group were significantly lower than those of the control female group. Adjusted vitamin A and coenzyme Q10 levels of the obese male group were significantly lower than those of the control male group. Insulin resistance level of the obese female and male groups were significantly higher than that of the control female and male groups. There were no significant correlations between serum coenzyme Q10, plasma vitamin A and E levels and insulin resistance in obese and control subjects. Our findings show that it is essential to use the lipid adjusted levels of lipid soluble nutrients in obesity. Also, we have found no association between insulin resistance and vitamin A, vitamin E and coenzyme Q10 levels in obese subjects
Zinc modulates several transcription-factor regulated pathways in mouse skeletal muscle cells
Zinc is an essential metal ion involved in many biological processes. Studies have shown that zinc can activate several molecules in the insulin signalling pathway and the concomitant uptake of glucose in skeletal muscle cells. However, there is limited information on other potential pathways that zinc can activate in skeletal muscle. Accordingly, this study aimed to identify other zinc-activating pathways in skeletal muscle cells to further delineate the role of this metal ion in cellular processes. Mouse C2C12 skeletal muscle cells were treated with insulin (10 nM), zinc (20 µM), and the zinc chelator TPEN (various concentrations) over 60 min. Western blots were performed for the zinc-activation of pAkt, pErk, and pCreb. A Cignal 45-Reporter Array that targets 45 signalling pathways was utilised to test the ability of zinc to activate pathways that have not yet been described. Zinc and insulin activated pAkt over 60 min as expected. Moreover, the treatment of C2C12 skeletal muscle cells with TPEN reduced the ability of zinc to activate pAkt and pErk. Zinc also activated several associated novel transcription factor pathways including Nrf1/Nrf2, ATF6, CREB, EGR1, STAT1, AP-1, PPAR, and TCF/LEF, and pCREB protein over 120 min of zinc treatment. These studies have shown that zinc’s activity extends beyond that of insulin signalling and plays a role in modulating novel transcription factor activated pathways. Further studies to determine the exact role of zinc in the activation of transcription factor pathways will provide novel insights into this metal ion actions
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