1,097 research outputs found
Comparative studies on Khaya. A. Juss (Meliaceae) in Nigeria
Comparative phytochemical, microscopical and chemomicroscopical studies were carried out on the genus Khaya with the aim of obtaining useful characters for the identification and delimitation of species boundaries. Tannins and saponins were present in all the species while phenols were detected in all except K. grandifoliola. Protein and anthraquinones were present in the bark of all the species. Carbohydrate is present in all the species except in the bark of K. ivoriensis. Flavonoids and phlobatannins were absent in all the taxa. Microscopical examination of the powdered bark revealed different types and shapes of lignified sclereids, abundant distribution of prismatic calcium oxalate crystals, druses, lignified cork-cells, fibres, medullary rays and parenchyma cells which may contain starch grain
Dense Deposit Disease: A 29-Years Electron Microscopy Experience
Introduction: Dense Deposit Disease (DDD) is a devastating renal disease that leads to renal failure within 10 years of diagnosis in about half of affected patients. In this study, we evaluated the relative prevalence and pathological features of DDD diagnosed at our center over a 29 years period.Methods: We reviewed the clinical and pathological features of all cases of DDD diagnosed at the Electron Microscopy Unit of Ain Shams University (ASUSH) between January 1983 and December 2011.Results: From a total of 3283 renal biopsies, 33 (1%) were diagnosed with DDD (10 children and 23 adults). Nephrotic syndrome was the predominant clinical presentation of DDD (51.5%), and was commoner in children than adults (80% vs. 43%, p=0.03). Capillary wall thickening was seen in all cases (100%). Crescents were more commonly seen in children than adults (70% vs. 21.7%, p=0.008) while interstitial fibrosis was more commonly seen in adults (78.3% vs. 40%, p=0.03). The commonest histological pattern seen under light microscopy was membranoproliferative (27.3%), followed by crescentic (21.2%), membranous (21.2%), diffuse proliferative (18.2%), lobular (6.1%) and mesangial proliferative (6.1%) patterns. Immunohistochemistry was available for 25 cases and showed intense linear staining for C3 along capillary walls. Electron microscopic examination revealed glomerular basement membrane (GBM) thickening and intra-membranous and tubular basement membrane deposits in all cases (100%).Conclusion: DDD is a rare disease in Egypt, found in only 1% of renal biopsies. Pathological features of the disease differ between adults and children; children have predominantly glomerular damage whereas tubule-interstitial lesions are more often encountered in adults.Key words: Dense Deposit Disease; Electron Microscopy; Membranoproliferative Glomerulonephritis; Nephrotic Syndrom
EEG changes and neuroimaging abnormalities in relevance to severity of autism
Background: Autism is currently viewed as a genetically determined neurodevelopmental disorder although its defi nite underlying etiology remains to be established.Aim of the Study: Our purpose was to assess autism related morphologicalneuroimaging changes of the brain and EEG abnormalities in correlation to the degree of disease severity.Patients and Methods: Seventeen cases with classic autism, 13 males and 4 females were included in the study. Severity of the disease was assessed both clinically and by Childhood Autism Rating Scale (CARS). MRI changes and EEG abnormalities were detected in seven patients, mostly severely and moderately affected.Results: Hypoplasia of cerebellar vermian lobules is the most replicated MRI abnormality in our patients (18%). Periventricular white matter dysmyelination is detected in 12% of studied cases. 29% of the cases have EEG abnormalities. Head circumference above 97th centiles is detected in 18% of cases. The increased head circumference, when in combination with EEG abnormalities, positively correlates with the degree of disease severity. Conclusion: Although, no defi nite correlation could be established between the studied parameters and disease severity, most patients in the present study who exhibited MRI abnormality, EEG changes and/or increased head circumference (H.C) manifested severe form of autism. The absence of correlation may be attributed to lack of statistical power, resulting from small sample size. However, the correlation was not solidly excluded therefore, the recommendation of further neuroradiological evaluation as well as the implementation ofnewer techniques, might help future elucidating the etiology of autism.Keywords: Autism, MRI, EEG, brain development
Demineralization-remineralization dynamics in teeth and bone
Biomineralization is a dynamic, complex, lifelong process by which living organisms control precipitations of inorganic nanocrystals within organic matrices to form unique hybrid biological tissues, for example, enamel, dentin, cementum, and bone. Understanding the process of mineral deposition is important for the development of treatments for mineralization-related diseases and also for the innovation and development of scaffolds. This review provides a thorough overview of the up-to-date information on the theories describing the possible mechanisms and the factors implicated as agonists and antagonists of mineralization. Then, the role of calcium and phosphate ions in the maintenance of teeth and bone health is described. Throughout the life, teeth and bone are at risk of demineralization, with particular emphasis on teeth, due to their anatomical arrangement and location. Teeth are exposed to food, drink, and the microbiota of the mouth; therefore, they have developed a high resistance to localized demineralization that is unmatched by bone. The mechanisms by which demineralization-remineralization process occurs in both teeth and bone and the new therapies/technologies that reverse demineralization or boost remineralization are also scrupulously discussed. Technologies discussed include composites with nano- and micron-sized inorganic minerals that can mimic mechanical properties of the tooth and bone in addition to promoting more natural repair of surrounding tissues. Turning these new technologies to products and practices would improve health care worldwide
Assessment of 1183 screen-detected, category 3B, circumscribed masses by cytology and core biopsy with long-term follow up data
Discrete masses are commonly detected during mammographic screening and most such lesions are benign. For lesions without pathognomonically benign imaging features that are still regarded likely to be non-malignant (Tabar grade 3) reliable biopsy results would be a clinically useful alternative to mammographic surveillance. Appropriate institutional guidelines for ethical research were followed. Between Jan 1996–Dec 2005 grade 3B discrete masses detected in the setting of a large, population based, breast cancer screening programme are included. Patient demographics, fine needle aspiration biopsy (FNAB), core and surgical biopsy results are tabulated. The final pathology of excised lesions was obtained. Information regarding interval cancers was obtained from the State Cancer Registry records and also through long term follow-up of clients in subsequent rounds of screening. A total of 1183 lesions, mean diameter of 13.3 mm (±8.3 mm) and mean client age of 55.1 years (±8.8 years) are included. After diagnostic work up, 98 lesions (8.3%) were malignant, 1083 were non-malignant and a final histologic diagnosis was not established in two lesions. In the 27 months after assessment, no interval cancers were attributable to these lesions and during a mean follow up of 54.5 months, available in 84.9% of eligible women, only one cancer has developed in the same quadrant as the original lesion, although the two processes are believed to be unrelated. FNAB performed in 1149 cases was definitive in 80.5% cases (882 benign, 43 malignant) with a negative predictive value (NPV) of 99.8% (880 of 882) and a positive predictive value (PPV) of 95.2% (40 of 42, both intraductal papillomas). Core biopsy was performed in 178 lesions, mostly for indefinite cytology. Core biopsy was definitive in 79.8% cases (57% benign 22% malignant) with a PPV of 100% and NPV of 99.0%. In experienced hands FNAB is an accurate first line diagnostic modality for the assessment of 3B screen-detected discrete masses, providing definitive results in 80.5% of cases. When used as a second line modality, core biopsy had a similarly high rate of definitive diagnosis at 79.8%. The stepwise approach to the use of FNAB and core biopsy would reduce substantially the proportion of cases requiring surgical diagnostic biopsy. Given the low probability of malignancy and the imperative to limit the morbidity associated with cancer screening, the demonstration of the reliability of FNAB as a minimally invasive but highly accurate test for this particular subset of screen-detected lesions has significant clinical utility
Paraneoplastic thrombocytosis in ovarian cancer
<p>Background: The mechanisms of paraneoplastic thrombocytosis in ovarian cancer and the role that
platelets play in abetting cancer growth are unclear.</p>
<p>Methods: We analyzed clinical data on 619 patients with epithelial ovarian cancer to test associations between platelet counts and disease outcome. Human samples and mouse
models of epithelial ovarian cancer were used to explore the underlying mechanisms
of paraneoplastic thrombocytosis. The effects of platelets on tumor growth and angiogenesis were ascertained.</p>
<p>Results: Thrombocytosis was significantly associated with advanced disease and shortened
survival. Plasma levels of thrombopoietin and interleukin-6 were significantly elevated
in patients who had thrombocytosis as compared with those who did not. In mouse
models, increased hepatic thrombopoietin synthesis in response to tumor-derived
interleukin-6 was an underlying mechanism of paraneoplastic thrombocytosis. Tumorderived interleukin-6 and hepatic thrombopoietin were also linked to thrombocytosis
in patients. Silencing thrombopoietin and interleukin-6 abrogated thrombocytosis in
tumor-bearing mice. Anti–interleukin-6 antibody treatment significantly reduced platelet counts in tumor-bearing mice and in patients with epithelial ovarian cancer. In
addition, neutralizing interleukin-6 significantly enhanced the therapeutic efficacy of
paclitaxel in mouse models of epithelial ovarian cancer. The use of an antiplatelet
antibody to halve platelet counts in tumor-bearing mice significantly reduced tumor
growth and angiogenesis.</p>
<p>Conclusions: These findings support the existence of a paracrine circuit wherein increased production of thrombopoietic cytokines in tumor and host tissue leads to paraneoplastic
thrombocytosis, which fuels tumor growth. We speculate that countering paraneoplastic thrombocytosis either directly or indirectly by targeting these cytokines may have
therapeutic potential. </p>
Macro-Climatic Distribution Limits Show Both Niche Expansion and Niche Specialization among C4 Panicoids
Grasses are ancestrally tropical understory species whose current dominance in warm open habitats is linked to the evolution of C4 photosynthesis. C4 grasses maintain high rates of photosynthesis in warm and water stressed environments, and the syndrome is considered to induce niche shifts into these habitats while adaptation to cold ones may be compromised. Global biogeographic analyses of C4 grasses have, however, concentrated on diversity patterns, while paying little attention to distributional limits. Using phylogenetic contrast analyses, we compared macro-climatic distribution limits among ~1300 grasses from the subfamily Panicoideae, which includes 4/5 of the known photosynthetic transitions in grasses. We explored whether evolution of C4 photosynthesis correlates with niche expansions, niche changes, or stasis at subfamily level and within the two tribes Paniceae and Paspaleae. We compared the climatic extremes of growing season temperatures, aridity, and mean temperatures of the coldest months. We found support for all the known biogeographic distribution patterns of C4 species, these patterns were, however, formed both by niche expansion and niche changes. The only ubiquitous response to a change in the photosynthetic pathway within Panicoideae was a niche expansion of the C4 species into regions with higher growing season temperatures, but without a withdrawal from the inherited climate niche. Other patterns varied among the tribes, as macro-climatic niche evolution in the American tribe Paspaleae differed from the pattern supported in the globally distributed tribe Paniceae and at family level.Fil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Biganzoli, Fernando. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Métodos Cuantitativos y Sistemas de Información; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bena, María Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Godoy Bürki, Ana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Reinheimer, Renata. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin
Urban Movement and Alcohol Intake Strongly Predict Defaulting from Tuberculosis Treatment: An Operational Study
BACKGROUND: High levels of defaulting from treatment challenge tuberculosis control in many African cities. We assessed defaulting from tuberculosis treatment in an African urban setting. METHODS: An observational study among adult patients with smear-positive pulmonary tuberculosis receiving treatment at urban primary care clinics in Kampala, Uganda. Defaulting was defined as having missed two consecutive monthly clinic visits while not being reported to have died or continued treatment elsewhere. Defaulting patients were actively followed-up and interviewed. We assessed proportions of patients abandoning treatment with and without the information obtained through active follow-up and we examined associated factors through multivariable logistic regression. RESULTS: Between April 2007 and April 2008, 270 adults aged ≥15 years were included; 54 patients (20%) were recorded as treatment defaulters. On active follow-up vital status was established of 28/54 (52%) patients. Of these, 19 (68%) had completely stopped treatment, one (4%) had died and eight (29%) had continued treatment elsewhere. Extrapolating this to all defaulters meant that 14% rather than 20% of all patients had truly abandoned treatment. Daily consumption of alcohol, recorded at the start of treatment, predicted defaulting (adjusted odds ratio [OR(adj)] 4.4, 95%CI 1.8-13.5), as did change of residence during treatment (OR(adj) 8.7, 95%CI 1.8-41.5); 32% of patients abandoning treatment had changed residence. CONCLUSIONS: A high proportion of tuberculosis patients in primary care clinics in Kampala abandon treatment. Assessing change of residence during scheduled clinic appointments may serve as an early warning signal that the patient may default and needs adherence counseling
Phase I dose escalation pharmacokinetic assessment of intravenous humanized anti-MUC1 antibody AS1402 in patients with advanced breast cancer
Knowledge of risk factors, beliefs and practices of female healthcare professionals towards breast cancer in a tertiary institution in Lagos, Nigeria
<p>Abstract</p> <p>Background</p> <p>Breast cancer is the leading female malignancy in Nigeria. Screening for early detection has led to reduction in mortality from the disease. It is known that attitudes of physicians and motivation by community nurses influence uptake of screening methods by women. This study aims to investigate knowledge of breast cancer risk factors, beliefs about treatment and practice of screening methods among a cohort of female healthcare professionals in Lagos, Nigeria.</p> <p>Methods</p> <p>A cross-sectional study was conducted using a self-administered questionnaire to assess the knowledge of breast cancer risk factors, beliefs about treatment and practice of screening methods among 207 female doctors, nurses and other healthcare professionals working in a university teaching hospital in Lagos, Nigeria. Stratified random sampling method was employed. Chi square test, analysis of variance and Mantel-Haenszel test were performed in data analysis using SPSS v10.0 and Epi Info version 6 statistical packages.</p> <p>Results</p> <p>Female doctors obtained a mean knowledge score of 74% and were the only professional group that had satisfactory knowledge of risk factors. Majority (86%) believed that early breast cancer is curable while half of participants believed that prayer can make breast cancer disappear from the affected breast. Eighty three percent practice breast self-examination (BSE) once a month and only 8% have ever had a mammogram. Age, knowledge of risk factors, profession and beliefs were not significantly associated with rate of BSE in this study.</p> <p>Conclusion</p> <p>Results from this study suggest the need for continuing medical education programmes aimed at improving knowledge of breast cancer among female healthcare providers other than doctors.</p
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