228 research outputs found

    A Study of the Genetics and Physical Properties of Dentine Defects

    Get PDF
    Dentinogenesis Imperfecta (DI) and Dentine Dysplasia (DD) are rare inherited condition affecting the dentine. Previous studies have reported the histological presentation of teeth with dentine defects but the differences between clinical appearances and physical properties, and how do they link to the underlying gene defects, is limited. In addition, the differences between primary and permanent teeth are poorly understood. Aim and Objective: The aim of this study was to investigate if there is an association between the underlying gene defect (genotype) and the physical properties and appearance (phenotype) of teeth with dentine defects. The objectives were to assess the colour, radiographic feature and dentine hardness of the teeth with dentine defects, to discover any other unidentified genes that might involve in causing inherited dentine diseases, and to relate them to the phenotype recorded clinically. Materials and Method: The discolouration and radiographic features of teeth from 16 patients (6 DI type I, 5DI type II, 4 OI and 1 DD type I respectively) were recorded. 20 control primary teeth and five DI teeth (four DI type I, one DI type II) were sectioned transversely using a diamond wheel saw. The dentine hardness measurement was done using Wallace Hardness Machine and recorded as Vickers Hardness Number (VHN). Dentine microstructure was examined using scanning electron microscope (SEM). Saliva samples were obtained from 14 patients for genomic analysis. Results: All DI type II and DI type I patients had marked discolouration of their teeth. DD and OI patients had normal teeth colour. The mean value of dentine hardness of control teeth was VHN=57.11±62. The VHN for DI teeth were significantly low compared to control teeth. The mean value for DI teeth was 30.61±8.24 VHN. Histologically, both DI type I and DI type II teeth showed reduced number of dentine tubules. DI type II had irregular dentine surface, while DI type I dentine showed a tear-like appearance on an empty dentine surface. Genetic analysis did not show any known mutations on COL1A1 and no novel genetic mutations has been observed. Conclusion: Collagen plays a role in maintenance of healthy dentine. Therefore, defects on COL1A1 and COL1A2 lead to abnormality of collagen thus the occurrence of OI and DI type I. Mutation in DSPP caused disruption in dentine mineralisation which also present as dentine defects in DI type II. Both DSPP and COL1A1/COL1A2 caused dentine abnormalities which present as teeth discolouration, abnormal appearance and reduced dentine hardness

    The effect of dose on the antimalarial efficacy of artemether-lumefantrine: a systematic review and pooled analysis of individual patient data

    Get PDF
    Background: Artemether-lumefantrine is the most widely used artemisinin-based combination therapy for malaria, although treatment failures occur in some regions. We investigated the effect of dosing strategy on efficacy in a pooled analysis from trials done in a wide range of malaria-endemic settings. Methods: We searched PubMed for clinical trials that enrolled and treated patients with artemether-lumefantrine and were published from 1960 to December, 2012. We merged individual patient data from these trials by use of standardised methods. The primary endpoint was the PCR-adjusted risk of Plasmodium falciparum recrudescence by day 28. Secondary endpoints consisted of the PCR-adjusted risk of P falciparum recurrence by day 42, PCR-unadjusted risk of P falciparum recurrence by day 42, early parasite clearance, and gametocyte carriage. Risk factors for PCR-adjusted recrudescence were identified using Cox's regression model with frailty shared across the study sites. Findings: We included 61 studies done between January, 1998, and December, 2012, and included 14 327 patients in our analyses. The PCR-adjusted therapeutic efficacy was 97·6% (95% CI 97·4-97·9) at day 28 and 96·0% (95·6-96·5) at day 42. After controlling for age and parasitaemia, patients prescribed a higher dose of artemether had a lower risk of having parasitaemia on day 1 (adjusted odds ratio [OR] 0·92, 95% CI 0·86-0·99 for every 1 mg/kg increase in daily artemether dose; p=0·024), but not on day 2 (p=0·69) or day 3 (0·087). In Asia, children weighing 10-15 kg who received a total lumefantrine dose less than 60 mg/kg had the lowest PCR-adjusted efficacy (91·7%, 95% CI 86·5-96·9). In Africa, the risk of treatment failure was greatest in malnourished children aged 1-3 years (PCR-adjusted efficacy 94·3%, 95% CI 92·3-96·3). A higher artemether dose was associated with a lower gametocyte presence within 14 days of treatment (adjusted OR 0·92, 95% CI 0·85-0·99; p=0·037 for every 1 mg/kg increase in total artemether dose). Interpretation: The recommended dose of artemether-lumefantrine provides reliable efficacy in most patients with uncomplicated malaria. However, therapeutic efficacy was lowest in young children from Asia and young underweight children from Africa; a higher dose regimen should be assessed in these groups. Funding: Bill and Melinda Gates Foundation

    Immunological properties of Oxygen-Transport Proteins: Hemoglobin, Hemocyanin and Hemerythrin

    Get PDF

    May Measurement Month 2018: a pragmatic global screening campaign to raise awareness of blood pressure by the International Society of Hypertension

    Get PDF
    Aims Raised blood pressure (BP) is the biggest contributor to mortality and disease burden worldwide and fewer than half of those with hypertension are aware of it. May Measurement Month (MMM) is a global campaign set up in 2017, to raise awareness of high BP and as a pragmatic solution to a lack of formal screening worldwide. The 2018 campaign was expanded, aiming to include more participants and countries. Methods and results Eighty-nine countries participated in MMM 2018. Volunteers (≥18 years) were recruited through opportunistic sampling at a variety of screening sites. Each participant had three BP measurements and completed a questionnaire on demographic, lifestyle, and environmental factors. Hypertension was defined as a systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg, or taking antihypertensive medication. In total, 74.9% of screenees provided three BP readings. Multiple imputation using chained equations was used to impute missing readings. 1 504 963 individuals (mean age 45.3 years; 52.4% female) were screened. After multiple imputation, 502 079 (33.4%) individuals had hypertension, of whom 59.5% were aware of their diagnosis and 55.3% were taking antihypertensive medication. Of those on medication, 60.0% were controlled and of all hypertensives, 33.2% were controlled. We detected 224 285 individuals with untreated hypertension and 111 214 individuals with inadequately treated (systolic BP ≥ 140 mmHg or diastolic BP ≥ 90 mmHg) hypertension. Conclusion May Measurement Month expanded significantly compared with 2017, including more participants in more countries. The campaign identified over 335 000 adults with untreated or inadequately treated hypertension. In the absence of systematic screening programmes, MMM was effective at raising awareness at least among these individuals at risk

    Late gadolinium uptake demonstrated with magnetic resonance in patients where automated PERFIT analysis of myocardial SPECT suggests irreversible perfusion defect

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Myocardial perfusion single photon emission computed tomography (MPS) is frequently used as the reference method for the determination of myocardial infarct size. PERFIT<sup>® </sup>is a software utilizing a three-dimensional gender specific, averaged heart model for the automatic evaluation of myocardial perfusion. The purpose of this study was to compare the perfusion defect size on MPS, assessed with PERFIT, with the hyperenhanced volume assessed by late gadolinium enhancement magnetic resonance imaging (LGE) and to relate their effect on the wall motion score index (WMSI) assessed with cine magnetic resonance imaging (cine-MRI) and echocardiography (echo).</p> <p>Methods</p> <p>LGE was performed in 40 patients where clinical MPS showed an irreversible uptake reduction suggesting a myocardial scar. Infarct volume, extent and major coronary supply were compared between MPS and LGE as well as the relationship between infarct size from both methods and WMSI.</p> <p>Results</p> <p>MPS showed a slightly larger infarct volume than LGE (MPS 29.6 ± 23.2 ml, LGE 22.1 ± 16.9 ml, p = 0.01), while no significant difference was found in infarct extent (MPS 11.7 ± 9.4%, LGE 13.0 ± 9.6%). The correlation coefficients between methods in respect to infarct size and infarct extent were 0.71 and 0.63 respectively. WMSI determined with cine-MRI correlated moderately with infarct volume and infarct extent (cine-MRI vs MPS volume r = 0.71, extent r = 0.71, cine-MRI vs LGE volume r = 0.62, extent r = 0.60). Similar results were achieved when wall motion was determined with echo. Both MPS and LGE showed the same major coronary supply to the infarct area in a majority of patients, Kappa = 0.84.</p> <p>Conclusion</p> <p>MPS and LGE agree moderately in the determination of infarct size in both absolute and relative terms, although infarct volume is slightly larger with MPS. The correlation between WMSI and infarct size is moderate.</p

    Regular Khat (Catha edulis) chewing is associated with elevated diastolic blood pressure among adults in Butajira, Ethiopia: A comparative study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Fresh leaves and buds of the Khat plant (<it>Catha edulis</it>) contain Cathinone, an amphetamine like alkaloid responsible for its pharmacological action. Chewing of Khat has been associated with a transient rise in blood pressure and heart rate in experimental studies. Few studies examined the effect of regular or frequent Khat chewing on blood pressure at the population level. This study was conducted to examine the association of regular Khat chewing with blood pressure among adults.</p> <p>Methods</p> <p>We compared systolic and diastolic blood pressure of adults 35-65 years of age who reported regular chewing of Khat during the preceding five years to those who never chewed Khat during the same period. Study participants were recruited from purposively selected urban and rural villages of Butajira District in Ethiopia. The comparative groups, chewers (334) and non-chewers (330), were identified from among the general population through a house-to-house visit using a screening questionnaire. They were frequency-matched for sex and age within a five-year range. Data were collected through structured interviews and physical measurements including blood pressure, weight and height.</p> <p>Results</p> <p>The prevalence of hypertension was significantly higher among Khat chewers (13.4%) than non-chewers (10.7%), odds ratio (OR) = 1.66 (95% confidence interval (CI) 1.05, 3.13). A considerably high proportion of chewers (29.9%) than non-chewers (20.6%) had sub-optimal diastolic blood pressure (> 80 mmHg). The mean (sd) diastolic blood pressure was significantly higher among Khat chewers [75.0 (11.6)] than non-chewers [72.9 (11.7)], P < 0.05. Similarly, Khat chewers had significantly higher mean (sd) heart rate [76.3 (11.5)] than non-chewers [73.9 (12.6)], P < 0.05. There was no significant difference in mean systolic blood pressure between the two groups.</p> <p>Conclusion</p> <p>Regular chewing of Khat is associated with elevated mean diastolic blood pressure, which is consistent with the peripheral vasoconstrictor effect of Cathinone. Regular Khat chewing may have sustained effects on the cardiovascular system that can contribute to elevated blood pressure at the population level.</p
    corecore