34 research outputs found
Tobacco Induced Priapism in Wister Rat: A Case Report
In an eight-week study on the effect of potash-tobacco dust ingestion on rats, a persistent penile erection for days was observed amongst some of the rats under study. This study involved a total of 42 Wister rats of weights rangingbetween 150-300g and grouped into four groups (A, B, C and D). Group A served as control, while groups B – Dserved as test groups and received 2g, 4g, and 6g of tobacco-dust, as well as 0.4g, 0.8g, and 1.2g of potash respectively, with water given ad libitum. By the 4th week, a persistent penile erection was observed in one of the rats in group C, and by the 6th week, a similar incident occurred in group C and D respectively, prompting serial observation. By the 8 week, gangrenous changes were observed, followed by necrosis and death of the rats on the 10th day from onset. The control rats (group A), which received normal feed and water, remained normal.Keywords: Priapism, Rat, Tobacco, Potash, Penile erectio
Tobacco Induced Renal Function Alterations in Wistar Rats: An 8 Weeks Study
This study investigates the effect of tobacco snuff on renal function using Wistar rat as a model. It involved adult rats (n=42) weighing 150-300g. They were assigned into a control group (A; n=6) and test groups B (n=12), C (n=12) and D (n=12). The groups were further divided into subgroups (1, 2, 3 and 4) representing durations of 2, 4, 6 and 8 weeks respectively. The test groups were fed varying doses of tobacco snuff (tobacco plus potash). At the end of every 2 weeks, three randomly selected rats were prepared for blood sample collection into lithium heparin containers for laboratory analysis of creatinine, urea and uric acid. Results showed that creatinine levels of the testrats were higher than the control, but the recorded values were however, duration dependent. Interestingly, a similar but irregular pattern was observed for urea and uric acid levels. Over all, the significant increase (P<0.05) in renal function parameters of the test rats (as compared to the control values), suggests that the ingestion of tobacco snuff has harmful effects on kidney functions.Keywords: Tobacco, Snuff, Kidney function, Nicotine substitute
The Effect of Tobacco Snuff Consumption on Liver Enzymes
This study was designed to investigate the changes in liver biochemical profile following oral tobacco dust ingestion. Adult Wistar rats (42) weighing 150-300g were involved. They were divided into four groups; group A serving as control, while groups B, C and D served as the test groups. The test groups were further divided into four groups (B1, C1, D1; B2, C2, D2; B3, C3, D3; and B4, C4, D4) representing four experimental phases/duration of 2, 4, 6 and 8 weeks respectively. The rats were fed with varying doses of tobacco dust mixed with potash. At the end of each phase, the animals were sacrificed and blood sample collected into lithium heparin and EDTA containers. Liver parameters (AST, ALT, ALP and GGT) were assayed and the results obtained showed statistically significant impairment of liver function. There was significant increase (p<0.05) in serum AST, ALT, and GGT levels in the different phases when the test groups were compared with the control. However, ALP shows no statistically significant increase in all the groups throughout the experiment. The results of this study suggest that potash-tobacco dust (local tobacco snuff) is toxic to the liver and the observed changes were dose and duration dependent.Keywords: tobacco, potash, liver function, liver enzymes
Cognitive reserve and cognitive performance of patients with focal frontal lesions
The Cognitive reserve (CR) hypothesis was put forward to account for the variability in cognitive performance of patients with similar degrees of brain pathology. Compensatory neural activity within the frontal lobes has often been associated with CR. For the first time we investigated the independent effects of two CR proxies, education and NART IQ, on measures of executive function, fluid intelligence, speed of information processing, verbal short term memory (vSTM), naming, and perception in a sample of 86 patients with focal, unilateral frontal lesions and 142 healthy controls. We fitted multiple linear regression models for each of the cognitive measures and found that only NART IQ predicted executive and naming performance. Neither education nor NART IQ predicted performance on fluid intelligence, processing speed, vSTM or perceptual abilities. Education and NART IQ did not modify the effect of lesion severity on cognitive impairment. We also found that age significantly predicted performance on executive tests and the majority of our other cognitive measures, except vSTM and GNT. Age was the only predictor for fluid intelligence. This latter finding suggests that age plays a role in executive performance over and above the contribution of CR proxies in patients with focal frontal lesions. Overall, our results suggest that the CR proxies do not appear to modify the relationship between cognitive impairment and frontal lesions
Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.
BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700
Cerebral microdialysis in clinical studies of drugs: pharmacokinetic applications
The ability to deliver drug molecules effectively across the blood–brain barrier into the brain is important in the development of central nervous system (CNS) therapies. Cerebral microdialysis is the only existing technique for sampling molecules from the brain extracellular fluid (ECF; also termed interstitial fluid), the compartment to which the astrocytes and neurones are directly exposed. Plasma levels of drugs are often poor predictors of CNS activity. While cerebrospinal fluid (CSF) levels of drugs are often used as evidence of delivery of drug to brain, the CSF is a different compartment to the ECF. The continuous nature of microdialysis sampling of the ECF is ideal for pharmacokinetic (PK) studies, and can give valuable PK information of variations with time in drug concentrations of brain ECF versus plasma. The microdialysis technique needs careful calibration for relative recovery (extraction efficiency) of the drug if absolute quantification is required. Besides the drug, other molecules can be analysed in the microdialysates for information on downstream targets and/or energy metabolism in the brain. Cerebral microdialysis is an invasive technique, so is only useable in patients requiring neurocritical care, neurosurgery or brain biopsy. Application of results to wider patient populations, and to those with different pathologies or degrees of pathology, obviously demands caution. Nevertheless, microdialysis data can provide valuable guidelines for designing CNS therapies, and play an important role in small phase II clinical trials. In this review, we focus on the role of cerebral microdialysis in recent clinical studies of antimicrobial agents, drugs for tumour therapy, neuroprotective agents and anticonvulsants
Predicting age from cortical structure across the lifespan
Despite inter-individual differences in cortical structure, cross-sectional and longitudinal studies have demonstrated a large degree of population-level consistency in age-related differences in brain morphology. The present study assessed how accurately an individual’s age could be predicted by estimates of cortical morphology, comparing a variety of structural measures, including thickness, gyrification, and fractal dimensionality. Structural measures were calculated across up to seven different parcellation approaches, ranging from 1 region to 1000 regions. The age-prediction framework was trained using morphological measures obtained from T1-weighted MRI volumes collected from multiple sites, yielding a training dataset of 1056 healthy adults, aged 18-97. Age predictions were calculated using a machine-learning approach that incorporated non-linear differences over the lifespan. In two independent, held-out test samples, age predictions had a median error of 6-7 years. Age predictions were best when using a combination of cortical metrics, both thickness and fractal dimensionality. Overall, the results reveal that age-related differences in brain structure are systematic enough to enable reliable age prediction based on metrics of cortical morphology