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OBJECTIVE: The aim of the study was to review all the cases of ameloblastoma seen at the Oral and Maxillofacial Surgery Clinic of the Lagos University Teaching Hospital, Nigeria, between 1980 and 2003. METHODS AND MATERIALS: In this retrospective study, case files and biopsy reports of new cases of ameloblastoma covering a 24-year period were retrieved and analyzed for sex, age on presentation, histologic type, and site distribution. RESULTS: A total of 207 cases of ameloblastoma were seen in the given period. One hundred and ninety-eight (95.7%) were benign, and 9 (4.3%) were malignant. A male-to-female ratio of 1.1:1 was found. The average ages on presentation for ameloblastoma and ameloblastic carcinoma were 31.67 and 46.44 years, respectively. The lesion was found to be more common in the premolar-molar region of the mandible. The most common histologic type was follicular ameloblastoma (25.1%). Nine (4.3%) cases of ameloblastic carcinoma were also reported. CONCLUSIONS: Ameloblastoma with a predilection for the posterior mandibular region is relatively common in our environment. Sex and site distributions are similar to previous reports in the literature.  相似文献   
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BACKGROUND CONTEXTBack and neck pain secondary to disc degeneration is a major public health burden. There is a need for therapeutic treatments to restore intervertebral disc (IVD) composition and function.PURPOSETo quantify ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens collected from patients undergoing surgery for disc degeneration, to correlate ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens to the 5-level Pfirrmann MRI grading system, and to compare ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression between cervical and lumbar degenerative disc specimens.STUDY DESIGNAn immunohistochemical study assessing ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in human control and degenerative IVD specimens.METHODSHuman IVD specimens were collected from surgical patients who underwent discectomy and interbody fusion at our institution between 1/2015 and 8/2017. Each patient underwent MRI prior to surgery. The degree of disc degeneration was measured according to the 5-level Pfirrmann MRI grading system. Patients were categorized into either the 1) control group (Pfirrmann grades I-II) or 2) degenerative group (Pfirrmann grades III-V). Histology slides of the collected IVD specimens were prepared and immunohistochemical staining was performed to assess ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in the control and degenerative specimens. Expression levels were also correlated to the Pfirrmann criteria. Lastly, the degenerative specimens were stratified according to their vertebral level and expression levels between the degenerative lumbar and cervical discs were compared.RESULTSFifty-two patients were enrolled; however, 2 control and 2 degenerative patients were excluded due to incomplete data sets. Of the remaining 48 patients, there were 12 control and 36 degenerative specimens. Degenerative specimens had increased expression levels of BMP-2 (p=.0006) and pSMAD1/5/8 (p<.0001). Pfirrmann grade 3 (p=.0365) and grade 4 (p=.0008) discs had significantly higher BMP-2 expression as compared to grade 2 discs. Pfirrmann grade 4 discs had higher pSMAD1/5/8 expression as compared to grade 2 discs (p<.0001). There were no differences in ALK3 or MMP-13 expression between the control and degenerative discs (p>.05). Stratifying the degenerative specimens according to their vertebral level showed no significant differences in expression levels between the lumbar and cervical discs (p>.05).CONCLUSIONSBMP-2 and pSMAD1/5/8 signaling activity was significantly upregulated in the human degenerative specimens, while ALK3 and MMP-13 expression were not significantly changed. The expression levels of BMP-2 and pSMAD1/5/8 correlate positively with the degree of disc degeneration measured according to the Pfirrmann MRI grading system.CLINICAL SIGNIFICANCEBMP-SMAD signaling represents a promising therapeutic target to restore IVD composition and function in the setting of disc degeneration.  相似文献   
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Recent advances in in vitro metabolism methods have led to an improved ability to predict clinically relevant metabolic drug-drug interactions. To address the relationships of in vitro metabolism data and in vivo metabolism outcomes, the Office of Clinical Pharmacology and Biopharmaceutics in the Center for Drug Evaluation and Research, Food and Drug Administration, evaluated a number of recently approved new drug applications. The goal of these evaluations was to determine the contribution of in vitro metabolism data in (1) predicting in vivo drug-drug interactions, (2) determining the need to conduct an in vivo drug-drug interaction study, and (3) incorporating findings into drug product labeling. Ten cases are presented in this article. They fall into two major groups: (1) in vitro data were predictive of in vivo results, and (2) in vitro data were not predictive of in vivo results. Discussion of these cases highlights factors limiting predictability of in vivo metabolic interactions from in vitro metabolism data. The integration of these findings into drug product labeling is also discussed.  相似文献   
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Hepatitis B virus (HBV) infection has been reported to be the aetiological factor for hepatocellular carcinoma (HCC), hepatitis and liver cirrhosis. This study was therefore carried out to determine the seroprevalence of hepatitis B surface antigen (HBsAg), a specific marker of HBV infection in patients with suspected liver diseases. The investigation was carried out among patients attending the University of Maiduguri Teaching Hospital (UMTH), Nigeria with clinical symptoms suggestive of liver diseases and others with non-specific clinical features during the period from 1990-1995. A total of 197 (38%) of 517 patients tested positive for HBsAg, 81 (49%) out of 144 with symptoms suggestive of hepatitis, 75 (50%) of 149 HCC and 10 (56%) of 18 liver cirrhosis were HBsAg positive. Comparison of the yearly total prevalence values of HBsAg for the six years under study showed no significant difference. Similarly, yearly prevalence values amongst patients with suspected liver diseases showed no significant differences. Nevertheless, significant difference, (P < 0.05) between the prevalence of HBsAg among suspected cases of liver diseases and others with non-specific signs and symptoms was observed. Similarly, HBsAg was statistically significantly higher among males than females. The high prevalence rate of HBsAg in our environment may be associated with the suspected cases of liver diseases, which are equally prevalent in our locality. Health education to prohibit traditional practices that could predispose individuals to HBV infections is emphasised. The incorporation of HBV vaccination in the national programme on immunization currently in use in Nigeria is highly recommended. This would be an effective method of preventing HBV infection from childhood.  相似文献   
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A substantial number of epileptic patients are resistant to the current medication thus necessitating the search for alternative therapies for intractable forms of the disease. Previous studies demonstrated the acute anticonvulsant properties of the methanol extract of the stem bark of Psychotria camptopus (MEPC) in rats. This study investigated the effects of MEPC on pentylenetetrazole-kindled Wistar rats. Kindling was induced by intraperitoneal injection of pentylenetetrazole (37.5 mg/kg) on every alternate day, 1 h after each daily oral pretreatment of rats (8?≤?n?≤?10) with MEPC (40, 80 and 120 mg/kg), vehicle or diazepam (3 mg/kg) for 43 days. The kindling development was monitored based on seizure episodes and severity. Rats’ brains were collected on day 43 for the determination of oxidative stress parameters. The histomorphological features and neuronal cell viability of the prefrontal cortex (PFC) and hippocampus were also assessed using H&E and Cresyl violet stains. Chronic administration of pentylenetetrazole time-dependently decreased the latency to myoclonic and generalized seizures, and increased seizure scores and the number of kindled rats. MEPC and diazepam significantly increased the latencies to myoclonic jerks and generalized tonic-clonic seizures. These substances also reduced seizure score and the number of rats with PTZ-kindling. MEPC improved glutathione status and decreased lipid peroxidation in the brains of kindled rats. MEPC also exhibited neuroprotection against pentylenetetrazole-induced hippocampal and PFC neuronal damages. These results suggest that P. camptopus has antiepileptogenic activity, which might be related to the augmentation of antioxidant and neuroprotective defense mechanisms, and further confirm its usefulness in the management of epilepsy.

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BackgroundSuicide is a global public health problem and Nigeria is one of the epicentres of suicide in the world. However, there is a dearth of research exploring the epidemiological aspects of suicide in Nigeria.AimTo examine the demographic information and precipitating events for suicides in Nigeria by analysing the contents of newspaper reports of suicide.MethodsWe searched, collected, and analysed published news reports about suicide from 10 English newspapers in Nigeria. A total of 350 suicide reports were assessed between January 2010 and December 2019 after screening and sorting.ResultsThe mean (SD) age of the reported cases was 36.33 (15.48) years. Majority of the reported cases were male (80.6%), married (51.8%), students (33.6%), living in a semi-urban area (40.3%) and among the age group of 25–34 (25.3%). Hanging (48.6%) and poisoning (32.2%) were the most commonly reported methods of suicide. Financial constraints and marital conflicts were most commonly assumed precipitating factors.ConclusionThis study suggests that being male, married, or living in semi-urban areas are associated with suicide in Nigeria. Further community-based studies are warranted to generalise the findings and adopt appropriate preventive strategies.  相似文献   
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Globally, the exodus of individuals who have been forced to flee their home and seek refuge in countries of safety has led to a refugee crisis. The United Kingdom (UK) has engaged with the United Nations High Commissioner for Refugees (UNHCR) in playing a significant role in the long‐term resettlement of refugees, half of whom are children and young people. One initiative of such humanitarian resettlement is the Gateway Protection Programme (GPP). To date, there is a dearth of studies investigating aspects of acculturation that affect the mental health of young refugees resettled under the UNHCR humanitarian programme. This study aimed to explore aspects of acculturation that could enhance the mental health of GPP young refugees several years after resettlement. Using narrative research, a purposive sample of 31 GPP young refugees, who had a minimum of three‐year stay in the UK, were recruited from local refugee community organizations. Data were collected through a multi‐method design combining focus group discussions (FGDs) with visual arts‐based narrative research (VABNR) and analysed thematically. Three overarching themes emerged: People and places; Its nearly all new to me; and Finding self. This study contributes important knowledge regarding the mental well‐being of young people who have engaged in a resettlement programme and offers valuable information for policymakers and mental health professionals working with GPP young refugees.  相似文献   
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