202 research outputs found

    Dataset from Effects of methanolic extract of Moringa oleifera leaves on fructose-induced metabolic dysfunction in growing Sprague Dawley rats

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    Methods Preparation of Moringa oleifera leaves extracts Moringa oleifera fresh leaves (7.5 kg) were sourced from the Agricultural Research Council Research (ARC) Farm, Roodeplaat, Pretoria, South Africa. The plant was authenticated and a voucher specimen (Id: J 103704) deposited at the Moss Herbarium of the University of the Witwatersrand in Johannesburg, South Africa. The leaves were desiccated in an oven (Salvis®, Salvis Lab, Schweiz, Switzerland) set at 40ºC. The leaves were then pulverized using a blender (Waring Commercial Blender, HGB2WTG4, USA). Within a 24 hour period, the powder was extracted with absolute methanol (Merck (pty) Ltd, South Africa) (100 g in 400 ml) on a shaker. The mixture was then filtered through Whatmann No.1 filter paper, and concentrated using a rotary evaporator (Buchi Rotavapor-R, Buchi Laboratoriums Technik AG, Schweiz, Switzerland) at 40°C. The condensed extract was then oven-dried (Salvis®, Salvis Lab, Schweiz, Switzerland) at 40°C. A 6% yield of dried extract was obtained and then stored in tightly sealed dark bottles at -4°C until use. Design of the experiment The Animal Ethics Screening Committee (AESC) of the University of the Witwatersrand approved the study (Reference No: 2015/11/51/B) which was conducted according to the internationally accepted principles for laboratory animal use and care as stipulated in South African National Standard (SANS 10386:2008) and Animals Protection Act, 1962: Act No. 71. Fifty 21-day old weaned male Sprague-Dawley rats weighing between 40-60g were individually housed in a well ventilated room at a temperature of 26±2°C in the Central Animal Service, University of the Witwatersrand, Johannesburg. The animal room was maintained on a 12-hour alternating light and dark cycle (illumination turned off between 7pm-7am). Standard rat polycarbon cages which contained clean wood shavings for bedding were used to house the rats individually. The treatment intervention commenced after the rats were allowed two days of adaptation to the environment. Pups were randomly allocated to six treatment groups which all received commercially sourced rat chow [LabChef Rodent Breeder, Nutritionalhub (PTY) LTD, Stellenbosch, South Africa] formulated to meet the nutritional requirements of rats ad libitum for the 10 week period of intervention. Plain drinking water and plain gelatine cubes were given to Group I (C; n=9); 20% fructose solution as drinking fluid (Mamikutty et al. 2015) and plain gelatine cubes were given to Group II (Fr; n= 9) to induce metabolic dysfunction; 20% fructose solution as drinking fluid and 400 mg.kg-1 body weight of methanolic extract of M. oleifera (Muhammad et al. 2018) were given to Group III (Fr + Mo; n= 8) in which the prophylactic effects of the Moringa extracts were investigated against fructose induced metabolic dysfunction; 20% fructose solution as drinking fluid and 100 mg.kg-1 body weight of fenofibrate (Sigma-Aldrich, France) (Abd El-Haleim et al. 2016) were given to Group IV (Fr + Fn; n= 8) as the positive control group; 400 mg.kg-1 body weight of methanolic extract of M. oleifera and plain drinking water were given to Group V (Mo; n= 8) to investigate the effects of Moringa alone and 100 mg.kg-1 body weight of fenofibrate and plain drinking water were given to Group VI (Fn; n= 8) to investigate the effects of fenofibrate alone. Flavoured gelatine cubes (2 ml) were used to suspend the Moringa extracts and fenofibrate and were given one daily. The fructose solution and plain drinking water were provided ad libitum. Measurement of body mass The rats were weighed at induction, thereafter they were weighed twice a week to determine gain in body mass and monitor growth performance in order to ensure that the rats received appropriate doses of the treatments. Procedures performed at termination A day prior to termination, the rats were fasted of feed for 12 hours overnight with access to plain drinking water. The terminal body masses of the rats were obtained and thereafter two drops of blood were taken following a pin prick to the tail vein. The fasting blood concentrations of glucose and triglycerides were measured using a glucose meter (Contour Plus Bayer Health Care, Diabetes Care, Isando, South Africa) and a triglyceride meter (Accutrend, Roche Diagnostics, Germany) respectively. An intraperitoneal injection of sodium pentobarbitone (Centaur Laboratories, Johannesburg, South Africa) at 150 mg.kg-1 body weight was used to euthanase the rats. The ventral thorax and abdomen were incised along the midline, and intra-cardiac blood was drawn and transferred into heparinized vacutainers and then centrifuged (Rotofix 32A, Hettich Zentrifugen, Germany) at 3700 revolutions per minute for 15 minutes. The harvested plasma was stored at -20˚C for later use. The liver, visceral and epididymal fat were removed, weighed and expressed relative to terminal body mass. A section of each liver sample was preserved at minus 20˚C for lipid content determination while rest was fixed in 10% phosphate buffered formalin for histological evaluation. Hepatic lipid content determination The frozen stored liver samples were lyophilised, milled and pooled into a composite sample for each group. Hepatic lipid content was quantified in triplicate for each group by solvent (petroleum ether) extraction at an accredited laboratory of the Agricultural Research Council (Irene Analytical Services Laboratory) using Tecator Soxtec apparatus with standard protocols (Official Methods of Analysis of Analytical Chemists, 2005). Histological examination of the liver The fixed liver samples were processed with an automatic tissue processor (Microm STP 120, ThermoScientific, MA, USA), embedded in paraffin wax, sectioned at 5µm using a rotary microtome [Leica Instruments GmbH, (PTY) LTD, Germany] and stained with hematoxylin and eosin (H&E) or Masson’s trichrome and then cover slipped. The H&E slides were viewed under a light microscope (×100) to evaluate the progression of fatty liver. Similarly, the Masson’s trichrome stained slides were viewed under a light microscope (×40) to determine collagen deposition and fibrosis. General health profile markers A VetTest analyser (IDEXX VetTest® Clinical Chemistry Analyser, IDEXX Laboratories Inc., USA) was used to determine the plasma concentrations of cholesterol, blood urea nitrogen (BUN), creatinine and activity of alanine aminotransferase (ALT). Fasting serum insulin concentration (ng.ml-1) was ascertained using an Enzyme Linked Immuno-Sorbent Assay kit (Elabscience Biotechnology Co., Ltd), which was then expressed as (µU.ml-1) using the formula (Darby et al. 2001): 1 ng.ml-1 of insulin is equivalent to 0.02 µU.ml-1 The insulin resistance index was computed according to the Homeostasis Model of Assessment (HOMA-IR) using the following formula (Divi et al. 2012): “HOMA-IR = fasting insulin (µU.ml-1) × fasting glucose (mmol.l-1) ÷ 22.5” Statistical analysis Analysis of the data was done with GraphPad Prism 5.0v for windows (GraphPad Software, Inc. CA), and the data were expressed as mean ± standard deviation and analysed by means of a one-way analysis of variance (ANOVA). This was followed by a Bonferroni post hoc test for comparison of the means. Statistical significance was considered at P < 0.05.Cleaned data from the experiement conducted with 21-day old male Sprague-Dawley rats . These rats(n=50) were randomized to six treatment groups (n=8-9) with unlimited access to commercial rat feed. Either plain water (C) or 20% fructose solution (Fr) were provided to drink. 400 mg.kg-1 M. oleifera methanolic leaf extract (Mo) or 100 mg.kg-1 fenofibrate were also administered daily for ten weeks. Growth, circulating metabolites, visceral and epididymal fat pads mass, hepatic lipids and general health markers were assessed. Liver samples were histologically examined using H&E stain. Analysis of the data was done with GraphPad Prism 5.0v for windows (GraphPad Software, Inc. CA), and the data were expressed as mean ± standard deviation and analysed by means of a one-way analysis of variance (ANOVA). Statistical significance was considered at P < 0.05.We acknowledge the Medical Faculty Research Endowment Fund, Faculty of Health Sciences Research Committee and School of Physiology of the University of Witwatersrand, South Africa (Grant No: 001.401.8521101…PHSLMFR); National Research Foundation of South Africa (Grant No: IFR 2010041900009); Federal University Birnin Kebbi (Nigeria) and Tertiary Education Trust Fund of Nigeria for supporting the MSc candidate.The Animal Ethics Screening Committee (AESC) of the University of the Witwatersrand approved the study (Reference No: 2015/11/51/B) which was conducted according to the internationally accepted principles for laboratory animal use and care as stipulated in South African National Standard (SANS 10386:2008) and Animals Protection Act, 1962: Act No. 71. Fifty 21-day old weaned male Sprague-Dawley rats weighing between 40-60g were individually housed in a well ventilated room at a temperature of 26±2°C in the Central Animal Service, University of the Witwatersrand, Johannesburg. The animal room was maintained on a 12-hour alternating light and dark cycle (illumination turned off between 7pm-7am). Standard rat polycarbon cages which contained clean wood shavings for bedding were used to house the rats individually. The treatment intervention commenced after the rats were allowed two days of adaptation to the environment.List of variables 1. Body mass (g) 2. Glucose (mmol.l-1) 3. Insulin (ng.ml-1) 4. HOMA-IR index 5. Triglycerides (mmol.l-1) 6. Cholesterol (mg.dl-1) 7. Visceral fat pad (% body mass) 8. Epididymal fat pad (% body mass) 9. Liver (% body mass) 10. Alanine aminotransferase [ALT (U.l-1)] 11. Creatinine (mg.dl-1) 12. Blood urea nitrogen [BUN (mg.dl-1)] 13. U:Cr 14. Hepatic lipid storage (% liver mass)NSLdata subset maleHepatic lipid content determination The frozen stored liver samples were lyophilised, milled and pooled into a composite sample for each group. Hepatic lipid content was quantified in triplicate for each group by solvent (petroleum ether) extraction at an accredited laboratory of the Agricultural Research Council (Irene Analytical Services Laboratory) using Tecator Soxtec apparatus with standard protocols (Official Methods of Analysis of Analytical Chemists, 2005). Histological examination of the liver The fixed liver samples were processed with an automatic tissue processor (Microm STP 120, ThermoScientific, MA, USA), embedded in paraffin wax, sectioned at 5µm using a rotary microtome [Leica Instruments GmbH, (PTY) LTD, Germany] and stained with hematoxylin and eosin (H&E) or Masson’s trichrome and then cover slipped. The H&E slides were viewed under a light microscope (×100) to evaluate the progression of fatty liver. Similarly, the Masson’s trichrome stained slides were viewed under a light microscope (×40) to determine collagen deposition and fibrosis. General health profile markers A VetTest analyser (IDEXX VetTest® Clinical Chemistry Analyser, IDEXX Laboratories Inc., USA) was used to determine the plasma concentrations of cholesterol, blood urea nitrogen (BUN), creatinine and activity of alanine aminotransferase (ALT). Fasting serum insulin concentration (ng.ml-1) was ascertained using an Enzyme Linked Immuno-Sorbent Assay kit (Elabscience Biotechnology Co., Ltd), which was then expressed as (µU.ml-1) using the formula (Darby et al. 2001): 1 ng.ml-1 of insulin is equivalent to 0.02 µU.ml-1 The insulin resistance index was computed according to the Homeostasis Model of Assessment (HOMA-IR) using the following formula (Divi et al. 2012): “HOMA-IR = fasting insulin (µU.ml-1) × fasting glucose (mmol.l-1) ÷ 22.5

    Ocular morbidity in Sokoto State, Nigeria

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    Background: There is a paucity of population-based data on ocular morbidity globally. The objectives of the current study were to estimate the prevalence and magnitude of eye disorders and to determine the ophthalmic subspecialty requirements for the population of Sokoto state, Nigeria. The information generated may provide baseline data for planning of a comprehensive eye health services in the state. Materials and Methods: During an all-ages population based blindness survey in December 2005, persons selected through a multi-stage random sampling were examined for any ocular disorder using a magnifying loupe, penlight and a direct ophthalmoscope. Data was entered and analyzed by a statistician. Statistical tests were carried out using Epi info 6 software (Centre for disease control [CDC] Atlanta, Georgia). Results: A total of 4848 persons were examined which gave a response rate of 91%. A total of 943 persons of the sample had an eye disorder in at least 1 eye, giving an ocular morbidity prevalence of 19%. Children aged 0-9 years constituted the highest proportion (37.5%) of the examined subjects. About 57% of the study population were males. Disorders affecting the lens (9.34%) were the most common followed by conjunctival lesions (5.49%). The most common diagnosis was lens opacity (8.1%) followed by conjunctivitis (5.2%). The most common subspecialty requirements in the population are cataract microsurgery (41.7%), and cornea/anterior segment (33%). Conclusion: Our data demonstrates high burden of ocular diseases most of which are either preventable or treatable in the study population. We recommend provision of human resource and technology requirements to meet these demands

    Rapid Assessment of Avoidable Blindness Dataset: Nigeria, Sokoto, Wurno (2016)

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    Anonymous participant level dataset including variables for visual acuity, spectacle use, lens status, cause of vision impairment, cataract surgical history, barriers to cataract surgery and population count data for five-year age-gender groups for males and females 50 years and olde

    Effects of Methanolic Extract of Moringa oleifera leaves on Fructose-Induced Metabolic dysfunction in growing Sprague Dawley Rats

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    A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, School of Physiology in fulfilment of the requirements for the degree of Master of Science in Medicine. Johannesburg, South Africa, 2017.Excess dietary fructose intake has been associated with an increase in metabolic disorders. Traditionally, these disorders are managed by physical exercise, lifestyle modification, and by conventional drug therapy. A significant proportion of the population also depends on the therapeutic/prophylactic properties of natural plants for their medical problems. The tree Moringa oleifera is well recognized for its medicinal and nutritional properties. The plant is said to possess antiobesity, antilipidaemic, antidiabetic and hypotensive effects amongst other medicinal properties. Most previous studies that explored the effects of Moringa oleifera on metabolism used adult male experimental animal models without considering adult female and young growing animal models, despite the increasing prevalence of metabolic syndrome in females and growing children. This study thus investigated the impact of a methanolic extract of Moringa oleifera leaves on fructose-induced metabolic dysfunction in growing Sprague Dawley rats of both sexes. One hundred and two (102), 21 day old, weaned male and female pups were randomly allocated to six groups that were sex matched. All groups received standard commercially sourced rat chow ad libitum throughout the study. In addition, Group I (negative control) received tap water for drinking and plain gelatine cubes. Group II received 20% fructose solution as drinking fluid and plain gelatine cubes. Group III received 20% fructose solution as their drinking fluid and 400 mg.kg-1 body weight of methanolic extract of Moringa oleifera leaves suspended in gelatine cubes. Group IV received 20% fructose solution as their drinking fluid and 100 mg.kg-1 body weight of fenofibrate (positive control) suspended in gelatine cubes. Group V received 400 mg.kg-1 body weight of the methanolic leaf extracts of Moringa oleifera in gelatine cubes and had plain drinking water. Group VI received 100 mg.kg-1 body weight of fenofibrate in gelatine cubes and had access to plain drinking water. After 10 weeks of the interventions, the rats were euthanased by anaesthetic overdose following an overnight fast; and samples of blood and tissue were collected. The outcomes of the interventions on growth performance, morphometry of the gastro-intestinal tract organs, circulating metabolites, adiposity, liver lipid accumulation and general health markers were assessed. Data were expressed as mean ± standard deviation and analyzed by one-way or two-way analysis of variance (ANOVA) depending on the variables. The statistical significance of analyzed values was set at ≤ 5%. Administration of 20% fructose solution significantly elevated hepatic lipid content in both sexes (P<0.0001) and the concentration of circulating triglycerides in female rats (P<0.0001) compared with negative controls. These lipid elevations were prevented by the administration of 400 mg.kg-1 body weight of methanolic extract of Moringa oleifera leaves and by 100 mg.kg-1 body weight of fenofibrate (P≤0.05). The effect of fenofibrate was more pronounced than that of Moringa. Fenofibrate treated groups (both sexes) had hepatomegaly (P<0.0001), higher fasting blood glucose (FBG) (P<0.0001), higher alkaline phosphatase activity in plasma (P<0.05) and lower (P<0.05) epididymal fat relative to tibial length (males) compared with the other treatment groups. The plasma triglycerides and cholesterol levels were higher in females than in males (P<0.05). The absolute and relative visceral fat pad masses were also higher in females (P<0.05). There were no significant differences in the hepatic lipid content and creatinine levels between the two sexes (P>0.05). However, male rats had significantly higher levels of FBG, liver enzymes (ALT and ALKP), blood urea nitrogen (BUN), urea to creatinine ratio and higher organ morphometry than their corresponding females (P<0.0001). No adverse effects were observed with fructose or Moringa on growth, organ morphometry, determinants of metabolic dysfunction and surrogate markers of general health. However, hepatomegaly was observed in fenofibrate treated groups (P<0.0001). In the present study, sex differences were observed in the metabolic responses of growing Sprague Dawley rats to a high-fructose diet. In addition, the methanolic extract of Moringa oleifera leaves was beneficial in preventing the hypertriglyceridaemia and abnormal deposition of hepatic lipids in high-fructose fed animals. However, the extract was not effective in preventing fructose-induced visceral obesity in male animals. The use of methanolic leaf extracts of Moringa oleifeira should be further explored as a possible candidate prophylactic intervention in the fight against the global epidemic of diet induced metabolic dysfunction.LG201

    The potential of zingerone administered orally to neonatal rats as protection against high-fructose diet-induced metabolic derangements

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    A thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Faculty of Health Sciences, School of Physiology, University of the Witwatersrand, Johannesburg, 2021Management of metabolic disorders places a heavy burden on healthcare systems globally. Dietary manipulations during developmentally plastic periods including the early postnatal phase can result in long-term beneficial or adverse health outcomes. Consumption of high-fructose diets early in life increases the risk of developing metabolic syndrome and associated cardiovascular and renal complications. Zingerone, a phytochemical mainly isolated from ginger (Zingiber officinale), has been demonstrated to attenuate metabolic derangements in adult rats. The potential preventive effects of zingerone administered orally to neonatal male and female rats against the long-term development of high-fructose diet-induced metabolic derangements were investigated. Four-day old male and female Sprague Dawley rat pups (n = 79) were randomly grouped and gavaged with: 10 ml/kg body weight of distilled water (W), 10 ml/kg body weight 20% fructose solution (FS), 10 ml/kg body weight fructose solution + 40 mg/kg body weight of zingerone in distilled water (ZF), or 40 mg/kg body weight of zingerone in distilled water (ZW) pre-weaning. After weaning, W and ZW continued on unlimited tap water while FS and ZF continued on unlimited fructose solution for 10 weeks. Commercial rat feed was provided ad libitum. Food and fluid intake was evaluated. Blood samples were collected for metabolic assays and assessment of general health markers. Growth performance, adiposity, hepatic lipid accumulation, renal function pathology and gastro-intestinal tract (GIT) organs’ morphometry were assessed. Liver and kidney tissues were collected for histological evaluation. Food intake was decreased; overall caloric intake was increased due to fructose feeding in both sexes (P < 0.05; ANOVA). When compared with the negative controls, the high-fructose diet significantly raised the terminal body masses [Females (P < 0.0001; ANOVA)], body mass index (BMI) [Females (P = 0.0036; ANOVA)], concentrations of triglycerides, total cholesterol, low density lipoprotein cholesterol, triglycerides to high density lipoprotein cholesterol ratio, visceral fat mass relative to body weight [Both sexes (P < 0.05; ANOVA)] and empty carcass mass [Females (P = 0.0025; ANOVA)]. Neonatally administered zingerone prevented (P < 0.05; ANOVA) the fructose-induced increase in body mass and empty carcass mass (Females), and hypercholesterolemia (Both sexes). Lee index and glycaemic parameters were not affected by the interventions in both sexes (P > 0.05; ANOVA). 2 Rats on the high-fructose diet compared to the negative controls had significantly increased hepatic lipid content [(%), P = 0.0002 (Males), P < 0.0001 (Females); ANOVA] and hepatic steatosis score [(%), P = 0.0018 (Males), P < 0.0022 (Females); Kruskal-Wallis ANOVA]. Zingerone administered neonatally prevented (P < 0.05; Kruskal-Wallis ANOVA) the fructose induced increase in hepatic steatosis in both sexes. The plasma levels of uric acid, markers of liver function, lipid peroxidation and inflammation were not different (P > 0.05; ANOVA) across the different treatment groups in both sexes. The group administered fructose only had significantly [P = 0.0054 (Males), P = 0.0002 (Females); ANOVA] increased levels of kidney injury molecule 1 (KIM-1), and decreased urinary space area [P = 0.0001 (Males), P = 0.0016 (Females); ANOVA] compared to the controls. Neonatally administered zingerone prevented the fructose-induced increase in the levels of KIM-1 [P = 0.9262 (Males), P = 0.6667 (Females); ANOVA], and fructose-induced reduction in the urinary space area [P = 0.1505 (Males), P = 0.8265 (Females); ANOVA] when the combined fructose and zingerone administered group was compared with the negative controls. Sex related differences were observed in food, fluid and caloric intake, terminal mass, BMI, cholesterol subtypes, visceral fat percentage, GIT visceral organs and long bones’ morphometry and empty carcass mass (P < 0.05; ANOVA). In rats, zingerone can be used strategically in the neonatal phase for prophylactic management of long-term high-fructose diet-induced metabolic syndrome, non-alcoholic fatty liver disease and nephropathy. Future studies in human clinical trials should be undertaken to explore the applicability of these findings to reduce the burden of metabolic disease on healthcare systems.TL (2021

    Prevalence of presbyopia and spectacle correction coverage in a rural population of North West Nigeria

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    Murtala Muhammad Umar,1 Nasiru Muhammad,2 Mahmoud B Alhassan3 1Zamfara State Eye Care Programme, King Fahad IBN Abdul-Azeez Women and Children Hospital, Zamfara State, Nigeria; 2Ophthalmology Unit, Surgery Department, College of Health Sciences Usmanu Danfodiyo University, Sokoto, Nigeria; 3Department of Vitreoretina, National Eye Centre, Kaduna, Nigeria Purpose: To determine the prevalence of presbyopia, and near vision spectacle coverage in a rural population of Northwestern Nigeria. Study design: Cross sectional prevalence study. Subjects and methods: Six hundred and fifty people of at least 40 years of age, in 13 clusters (50 per cluster) were examined using a multi-stage random sampling with probability proportional to size. The survey was conducted from April 7 to 28, 2012 at Bungudu Local Government Area of Zamfara State, Nigeria. Presbyopia was defined as the inability to read N8 at 40 cm. Presbyopic Spectacle Correction Coverage (PSCC) was calculated, and information on barriers to using near vision spectacles identified. Results: The crude prevalence of presbyopia was 30.4%, 95% CI: (26.8%–34.1%). The prevalence was significantly higher in females (P=0.0005) and individuals with at least secondary education (P=0.022). The age specific prevalence of presbyopia was three times (63.5%) more among those aged 70 years and above, as compared to those within 40–49 years age group (19.3%). The met need was 0.2%, the unmet need 30.2%, and a PSCC of 0.7%. The major barriers reported as reasons for not obtaining near vision spectacles were unawareness and lack of felt need. Conclusion: The prevalence of presbyopia in Bungudu is relatively low compared to other reports with major risk factors being increasing age, female sex and attainment of higher education. The presbyopic spectacles correction coverage is very low with high unmet need thus there is a need to create awareness, and provide affordable and accessible optical services in the affected population. Keywords: presbyopia, spectacle coverage, Nigeri

    Correlation between diabetes mellitus and periodontal disease: A retrospective assessment of diabetics attending Murtala Muhammad Specialist Hospital, Kano

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    Periodontal disease is a common oral infection that affects the tissues that surrounds and support the teeth. The aim of the research was to study the relationship between diabetes and periodontal disease. The data was collected at Murtala Muhammad Specialist Hospital, Kano where a thorough review of patients’ record (files) who visited or were admitted at the facility within the period of January 2022-May 2023. Correlation coefficients showed the existence of a strong relationship between diabetes and periodontitis. Out of 80 patients with diabetes mellitus; 52(65%) had periodontal disease, 36(45%) were males and the disease was severe within the age range of 55-74; 16 (20%) were females with the disease being severe within the age range of 75 and above while 28 (35%) had no periodontal disease. Twenty percent of the patients had gingivitis, 15% have mild periodontitis, 20% have moderate periodontitis, 10% have severe periodontitis and 35% had no periodontitis. There exists strong relationship between diabetes mellitus and periodontal disease, the poorer the glycaemic control, and the longer the duration of diabetes mellitus; the greater will be the increased risk and severity of periodontitis
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