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1.
J Diabetes Metab Disord ; 23(1): 1371-1380, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38932804

RESUMO

Purpose: Our study investigated the association between dental caries, periodontal diseases, and tooth loss with diabetes mellitus (DM) among the elderly population, representing the first study of its kind in Iran. Methods: This was a cross-sectional community-based study as a part of the second wave of the Birjand longitudinal aging study (BLAS, 2021-2022) for people older than 60. We used the Comprehensive Geriatric Oral Health Assessment Tool (CGOHAT) for the oral health evaluation. Participants were initially categorized into diabetic and non-diabetic groups. Those patients with DM were further categorised into uncontrolled and controlled diabetes based on their HbA1c level. The association between periodontitis, gingivitis, and edentulism with type II diabetes mellitus and uncontrolled diabetes was assessed using logistic regression. Results: Among the 1,011 participants, 324 (32.04%) had DM. The mean ± SD DMFT was 27.06 ± 7.71 and 27.07 ± 7.72 among those with and without DM, respectively (p = 0.976). The M index comprised 85.46% of the total DMFT among those without DM and 84.51% among those with DM. The prevalence of periodontitis was higher among those without DM (110, 32.84%, p = 0.390). The prevalence of gingivitis was higher among those with DM (73, 45.06%, p = 0.617). Among the diabetic group, 137 (42.28%) had controlled DM. Based on the adjusted matched multivariate logistic model, decayed teeth (1.24, 95%CI: 1.06 - 1.46, p-value = 0.006), periodontitis (2.78, 95%CI: 1.02 - 7.56, p-value = 0.044), and moderate tooth loss (5.73, 95%CI: 1.13 - 28.88, p-value = 0.034) were significantly associated with increased odds of uncontrolled DM. Conclusions: Based on the findings of this study, tooth loss was highly prevalent among the elderly Iranians regardless of their diabetes status. Also, periodontitis, tooth loss, and decayed teeth were significantly associated with increased odds of poor glycemic control among those with DM. Thus, it can be concluded that improving the oral health of the geriatric population may be a crucial part of improving the glycemic control among those with diabetes which has been frequently neglected. Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-024-01434-2.

3.
Med J Islam Repub Iran ; 38: 11, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586500

RESUMO

Background: The prevalence of dental caries among the elderly is high worldwide, and dental caries cause the major burden of oral diseases. This meta-analysis aimed to determine the dental caries experience among the elderly in Iran. Methods: A systematic review of the published and grey literature on Iranians aged 65 years or older was performed. Six international and local databases provided the most comprehensive population-based studies. National oral health surveys and national disease and health surveys were considered other primary data sources. The quality of remained studies was assessed by a modified tool designed based on the STROBE statement checklist to evaluate the cross-sectional studies. R Version 3.6.0 was used for statistical analysis. Heterogeneity was assessed using Cochran's Q and F statistics. Subgroup analysis was performed to detect the source of heterogeneity. Funnel plots and Egger's regression intercept test were used to assess publication bias and selective reporting. Results: Overall, 3099 sources were found. After excluding ineligible studies, 46 data points with 10411 people ≥65 years were included in the meta-analysis. The mean pooled decayed, missing, and filled teeth (DMFT) among older people was 26.84 (range, 26.41-27.28). The DMFT was 26.78 (range, 26.12-27.43) in women and 26.91 (range, 26.32-27.50) in men. The mean number of decayed teeth was 1.48 (range, 1.32-1.65). The mean pooled missing teeth was 24.83 (range, 24.20-25.46), and the mean pooled filled teeth was 0.14 (range, 0.12-0.17). The majority (92%) of the DMFT was related to missing teeth. Conclusion: Iranian elderly have almost 5 sound teeth in their mouth on average. The Iranian oral health policymakers should address this considerable burden of dental caries in designing and implementing better oral health policies for the population, especially older Iranian adults.

4.
BMC Oral Health ; 24(1): 36, 2024 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-38185687

RESUMO

BACKGROUNDS: Cleft lip with or without cleft palate (CL/P) is the most common congenital craniofacial anomaly, including non-syndromic cleft lip with or without cleft palate and cleft palate only. Failure in the fusion of median and lateral nasal processes, the maxillary prominence, and soft tissues around the oral cavity can cause CL/P. Previously, the prevalence has been estimated to be 1 among every 1000 births in 2014 among American neonates and no other reports have been available since. Thus, this study aimed to calculate the prevalence and trend of isolated CL/P among American live births from 2016 to 2021 with its associated risk factors. METHODS AND MATERIALS: In this cross-sectional population-based retrospective study, we used live birth data provided by the National Center for Health Statistics (NCHS) from the Center for Disease Control and Prevention (CDC). We calculated the prevalence per 10,000 live births of isolated (non-syndromic) CL/P from 2016 to 2021. To examine risk factors for developing isolated CL/P, we used logistic regression modelling. RESULTS: The total prevalence per 10,000 births from 2016 to 2021 was 4.88 (4.79-4.97), for both sexes, and 5.96 (5.82-6.10) for males, and 3.75 (3.64-3.87) for females. The prevalence did not show any consistent linear decreasing or increasing pattern. We found significant association between increased odds of developing isolated CL/P among cases with 20 to 24 year-old mothers (OR = 1.07, 1.01-1.13, p = 0.013), mothers who smoked 11 to 20 cigarettes per day (OR = 1.46, 1.33-1.60, p <  0.001), mothers with extreme obesity (OR = 1.32, 1.21-1.43, p <  0.001), mothers with grade II obesity (OR = 1.32, 1.23-1.42, p <  0.001), mothers with pre-pregnancy hypertension (OR = 1.17, 1.04-1.31, p = 0.009), mothers with pre-pregnancy diabetes mellitus (OR = 1.96, 1.71-2.25, p <  0.001), and mothers who used assisted reproductive technology (OR = 1.40, 1.18-1.66, p <  0.001). CONCLUSIONS: Our findings suggest a minuscule increase, albeit insignificant, in the trend of CL/P prevalence from 2016 to 2021. Developing CL/P had greater odds among mothers with pre-pregnancy diabetes, smoking, obesity, and pre-pregnancy hypertension mothers along with mothers who used assisted reproductive technology. Isolated CL/P had the highest prevalence in non-Hispanic Whites, American Indian or Alaskan Native and Native Hawaiian and Other Pacific Islanders.


Assuntos
Fenda Labial , Fissura Palatina , Hipertensão , Feminino , Masculino , Recém-Nascido , Gravidez , Humanos , Adulto Jovem , Adulto , Fissura Palatina/epidemiologia , Fenda Labial/epidemiologia , Nascido Vivo/epidemiologia , Estudos Transversais , Prevalência , Estudos Retrospectivos , Fatores de Risco , Obesidade
5.
BMC Oral Health ; 24(1): 116, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38243206

RESUMO

BACKGROUND: Oral disorders are still a major global public health challenge, considering their perpetuating and chronic nature. Currently, there is no direct index to measure the quality of care on a population scale. Hence, we aim to propose a new index to measure the quality of care for oral disorders worldwide. METHODS: We generated our database using the data from the Global Burden of Disease (GBD) study 2017. Among different variables such as prevalence, incidence, years lived with disability, and disability-adjusted life years, we utilised principal component analysis (PCA) to determine the component that bears the greatest proportion of information to generate the novel quality of care index (QCI) for oral disorders. RESULTS: Global QCI for oral disorders gradually increased from 1990 to 2017 (from 70.5 to 74.6). No significant gender disparity was observed during this period, and the gender disparity ratio (GDR) was considered optimal in 1990 and 2017. Between 1990 and 2017, the age-standardised QCI for all oral disorders increased in all the SDI regions. The highest QCI for all oral disorders in 2017 belonged to high-middle SDI countries (=80.24), and the lowest YLDs rate was seen in the low SDI quintile. In 1990, the quality of care in European, Central Asian, and Central and South American countries was in the lowest quintiles, whereas the North American, East Asian, Middle Eastern, and some African countries had the highest quality of dental care. Maynmar (=100), Uganda (=92.5), Taiwan (=92.0), China (=92.5), and the United States (=89.2) were the five countries with the highest age-standardised QCI. Nicaragua (=41.3), Belgium (=40.2), Venezuela (=38.4), Sierra Leone (=30.5), and the Gambia (=30.3) were the five countries with the least age-standardised QCI values. CONCLUSION: The quality of care for all oral disorders showed an increasing trend on a global scale from 1990 to 2017. However, the QCI distribution was not homogenous among various regions. To prevent the exacerbation of imminent disparities in this regard, better attention to total tooth loss in high-income countries and prioritising primary healthcare provision in low-income countries are recommended for oral disorders.


Assuntos
Pessoas com Deficiência , Carga Global da Doença , Humanos , Prevalência , Incidência , Qualidade da Assistência à Saúde , Saúde Global , Anos de Vida Ajustados por Qualidade de Vida
6.
Int Dent J ; 74(1): 129-137, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37574408

RESUMO

OBJECTIVE: There are currently no integrated data on the trend of dental caries amongst distinct age groups in Iran. We aimed to assess the national and subnational trend of dental caries of permanent teeth in Iran from 1990 to 2017. METHODS: A literature search about dental caries and the decayed-missing-filled teeth index (DMFT) was performed in PubMed, Web of Science, Scopus, and 3 national databases (in Persian). All eligible national oral health surveys in these 28 years were included. We categorised and aggregated the DMFT values and their components based on age (5-year-based groups from 5 to 9 to 60+ years), sex, year, and province. The data for missing spots were estimated using the spatiotemporal Bayesian hierarchical model. We used the bootstrap method in multilevel models to predict the uncertainty interval (UI) of the modelled results. RESULTS: Nationally, the all-ages mean DMFT increased by nearly 58.0% (6.8 [95% UI, 4.1-10.5] in 1990 to 10.8 [95% UI, 7.5-14.5] in 2017). Decayed teeth (DT) and missing teeth (MT) rose by 84.5% and 31.6% during this period, respectively. Filled teeth (FT) showed almost a 2.6-fold increase in the same period from 0.6 (95% UI, 0.01-1.6) in 1990 to 1.7 (95% UI, 0.6-2.8) in 2017. The proportion of DT and FT continuously increased in both sexes. In 2017, the highest DT, MT, and FT were estimated in the 25-29 (4.9 [95% UI, 2.5-7.2]), 60+ (21.5 [95% UI, 17.5-25.4]), and 35-39 (2.6 [95% UI, 1.3-4.0]) year age groups. CONCLUSIONS: Caries of permanent dentition levies a growing burden on the Iranian population. Considering the continuous increase in caries during the 1990-2017 period, Iranian policymakers should pay heed to these findings and react more proactively to mitigate this perpetuating issue. Implementing nationwide interventions such as sugar consumption management should be encouraged to achieve sustainable outcomes in this regards.


Assuntos
Cárie Dentária , Perda de Dente , Masculino , Feminino , Humanos , Pré-Escolar , Dentição Permanente , Cárie Dentária/epidemiologia , Irã (Geográfico)/epidemiologia , Teorema de Bayes , Saúde Bucal , Índice CPO , Prevalência
7.
Clin Exp Dent Res ; 9(5): 879-886, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37767734

RESUMO

OBJECTIVES: Improving the oral health of the elderly is crucial to improving their general health and quality of life. To reach this goal, it is necessary to start with a comprehensive oral health assessment and a detailed treatment plan. The aim of this study was, therefore, to develop a comprehensive Oral Health Assessment Tool for the geriatric population. MATERIAL AND METHODS: Following a panel of experts' consultation, a clinical form and a self-assessment questionnaire were developed, encompassing eight domains: dental caries, periodontal diseases, partial and complete edentulism, oral soft tissue lesions, occlusion, xerostomia, temporomandibular joints, and oral or oral prostheses hygiene. Subsequently, a pilot study was conducted to appraise the clinical form and questionnaire involving 84 residents of an Iranian nursing home. After securing ethics approval, both the qualitative and quantitative aspects of the self-assessment questions' validity and reliability were assessed, and specificity and sensitivity were calculated. RESULTS: The mean age of the participants was 69.8 (±4.1) years, and 86% had less than 12 years of education. The questions regarding the number of remaining teeth and the number of decayed teeth had the highest sensitivity (97% and 88%), respectively. Questions regarding the presence of periodontitis and gingivitis had the highest specificity (both 100%). CONCLUSIONS: A Comprehensive Geriatric Oral Health Assessment Tool has been developed and its validity and reliability evaluated in a pilot study. It should now be further evaluated in larger studies.


Assuntos
Cárie Dentária , Implantes Dentários , Humanos , Idoso , Saúde Bucal , Cárie Dentária/diagnóstico , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Qualidade de Vida , Irã (Geográfico) , Projetos Piloto , Reprodutibilidade dos Testes
8.
Am J Obstet Gynecol MFM ; 5(10): 101105, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37527736

RESUMO

OBJECTIVE: This study aimed to evaluate the natural history of selective intrauterine growth restriction in monochorionic twin pregnancies based on the Gratacós classification, including progression of, improvement in, or stability of umbilical artery Dopplers and progression to twin-to-twin transfusion syndrome or twin anemia polycythemia syndrome. We also aimed to investigate risk factors for smaller twin demise. DATA SOURCES: A systematic search was performed to identify relevant studies published in English up to June 2022 using the databases PubMed, Scopus, and Web of Science STUDY ELIGIBILITY: We used retrospective and prospective studies published in English that reported on selective intrauterine growth restriction without concomitant twin-to-twin transfusion syndrome. STUDY APPRAISAL AND SYNTHESIS METHODS: Articles that investigated selective intrauterine growth restriction progression and outcomes by umbilical artery Doppler end-diastolic flow (Gratacós classification) were included. Type I included selective intrauterine growth restriction cases with positive end-diastolic flow, type II included those cases with persistently absent end-diastolic flow, and type III included cases with intermittent absent or reversed end-diastolic flow. Pregnancies in which a diagnosis of twin-to-twin transfusion syndrome or twin anemia polycythemia sequence was made before the diagnosis of selective intrauterine growth restriction were not included in the analysis. A random effects model was used to pool the odds ratios and the corresponding 95% confidence intervals. Heterogeneity was assessed using the I2 value. RESULTS: A total of 17 studies encompassing 2748 monochorionic pregnancies complicated by selective intrauterine growth restriction were included in the analysis. The incidence of stable, deteriorating, or improving umbilical artery Dopplers in type I cases was 68% (95% confidence interval, 26-89), 23% (95% confidence interval, 7-40), and 9% (95% confidence interval, 0.0-100), respectively. In type II cases, the incidence was 40% (95% confidence interval, 18-81), 50% (95% confidence interval, 23-82), and 10% (95% confidence interval, 4-37), respectively, and in type III cases, the incidence was 55% (95% confidence interval, 2-99), 23% (95% confidence interval, 9-43), and 22% (95% confidence interval, 6-54), respectively. The risk for progression to twin-to-twin transfusion syndrome was comparable between type I (7%) and type III (9%) cases and occurred in 4% (95% confidence interval, 0-67) of type II cases with no significant subgroup differences. Progression to twin anemia polycythemia syndrome was highest in type I cases (12%) and comparable between type II (2%) and III (1%) cases with no significant subgroup differences. Risk factors for smaller twin demise were earlier gestational age at diagnosis (mean difference, -2.69 weeks; 95% confidence interval, -4.94 to -0.45; I2, 45%), larger intertwin weight discordance (mean difference, 34%; 95% confidence interval, 1.35-5.38; I2, 28%), deterioration of umbilical artery Dopplers for each of type II and III cases (odds ratio, 3.05; 95% confidence interval, 1.36-6.84; I2, 24%; and odds ratio, 4.5; 95% confidence interval, 2.31-8.77; I2, 0.0%, respectively), and absent or reversed ductus venosus a-wave for each of type II and III cases (odds ratio, 3.35; 95% confidence interval, 2.28-4.93; I2, 0.0%; and odds ratio, 2.36; 95% confidence interval, 1.08-5.13; I2, 0.0%, respectively). Progression to twin-to-twin transfusion syndrome was not significantly associated with smaller twin demise for each of type II and III selective intrauterine growth restriction cases. CONCLUSION: These findings improve our understanding of the natural history of the types of selective intrauterine growth restriction and of the predictors of smaller twin demise in type II and III selective intrauterine growth restriction cases. The current data provide vital counseling points and support the need for modifications of the current selective intrauterine growth restriction classification system to include the variations in umbilical artery and ductus venosus Dopplers to better identify a cohort that might benefit from fetal intervention for which future multicenter prospective randomized trials are needed.


Assuntos
Transfusão Feto-Fetal , Policitemia , Gravidez , Feminino , Humanos , Recém-Nascido , Transfusão Feto-Fetal/diagnóstico , Transfusão Feto-Fetal/epidemiologia , Transfusão Feto-Fetal/terapia , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/epidemiologia , Retardo do Crescimento Fetal/etiologia , Estudos Prospectivos , Estudos Retrospectivos , Policitemia/diagnóstico , Policitemia/epidemiologia , Policitemia/etiologia , Morte Fetal/etiologia , Fatores de Risco , Estudos Multicêntricos como Assunto
9.
J Adv Res ; 49: 175-190, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36220592

RESUMO

INTRODUCTION: Recently, a new family of fractional derivatives called the piecewise fractional derivatives has been introduced, arguing that for some problems, each of the classical fractional derivatives may not be able to provide an accurate statement of the consideration problem alone. In defining this kind of derivatives, several types of fractional derivatives can be used simultaneously. OBJECTIVES: This study introduces a new kind of piecewise fractional derivative by employing the Caputo type distributed-order fractional derivative and ABC fractional derivative. The one- and two-dimensional piecewise fractional Galilei invariant advection-diffusion equations are defined using this piecewise fractional derivative. METHODS: A new class of basis functions called the orthonormal piecewise Vieta-Lucas (VL) functions are defined. Fractional derivatives of these functions in the Caputo and ABC senses are computed. These functions are utilized to construct two numerical methods for solving the introduced problems under non-local boundary conditions. The proposed methods convert solving the original problems into solving systems of algebraic equations. RESULTS: The accuracy and convergence order of the proposed methods are examined by solving several examples. The obtained results are investigated, numerically. CONCLUSION: This study introduces a kind of piecewise fractional derivative. This derivative is employed to define the one- and two-dimensional piecewise fractional Galilei invariant advection-diffusion equations. Two numerical methods based on the orthonormal VL polynomials and orthonormal piecewise VL functions are established for these problems. The numerical results obtained from solving several examples confirm the high accuracy of the proposed methods.


Assuntos
Algoritmos , Difusão
10.
BMC Oral Health ; 22(1): 634, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36564764

RESUMO

BACKGROUND: Dental caries is the most prevalent child affliction in the world and can be reduced through effective preventive interventions. To plan cost-effective interventions, clear and integrated data are needed. This study has been designed to overcome the lack of national trend in deciduous dental caries in Iran. OBJECTIVE: To estimate the dental caries trend in deciduous teeth in the Iranian population at different ages from 1990 to 2017. METHODS: From 1990 to 2017 a literature search about dmf and its components (decayed, missed, and filled tooth, abbreviated as dt, mt, and ft) as well as dental caries was done in the Iranian population in three English (PubMed, Web of Science, and Scopus) and three national databases (in Persian). All eligible national oral health surveys in these 28 years were included. National dmft data were categorised based on age (1-4, 5-9, and 10-14), sex, province and year. The final trends were estimated using an age-spatio-temporal hierarchical model. We used the bootstrap method in multilevel models to predict the uncertainty interval (UI) of the modelled results. Finally, the estimations of dmft, dt, mt, and ft with a 95% UI were reported from 1990 to 2017. RESULTS: Almost 22% of the Iranian deciduous teeth were involved with dental caries in 1990 [dmft = 4.37; (95% UI 2.23, 6.62)] which more than 83% of it was dt [3.64 (1.53, 5.88)] and less than 7% was ft [0.30 (0.06, 0.65)]. During 1990-2017, dmft increased by more than 15% [in 2017, dmft = 5.03 (2.82, 7.29)]. The highest increase was seen in dt which was more than 17% [in 2017, dt = 4.27 (1.96, 6.57)]. CONCLUSION: Increasing dental caries among Iranian children over 28 years shows that oral health policies in Iran need critical evaluation. We need cost-effective nationwide interventions (e.g., supervised tooth brushing and improving dietary habits) and training well-experienced intermediate manpower (e.g., dental hygienists) to reduce dental caries.


Assuntos
Cárie Dentária , Dente Decíduo , Criança , Humanos , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Índice CPO , Irã (Geográfico)/epidemiologia , Saúde Bucal , Prevalência , Escovação Dentária
11.
J Diabetes Metab Disord ; 21(1): 1195-1199, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35317104

RESUMO

As the first outbreak of COVID-19 in Wuhan, China, the elder population and those with comorbidities were at higher risk of COVID-19 infection. The mortality rate was also higher in this population. Hence, the management and prevention of this novel disease in nursing homes was of utmost importance. The health management team in Kahrizak Charity Foundation (KCF), a nursing home in Iran with more than 1400 elder or comorbid resident, have tackled the COVID-19 outbreak with a novel approach towards this problem. This commentary aims at sharing the insights and lessons learned in the management of COVID-19 in KCF. Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-022-01005-3.

12.
BMC Oral Health ; 21(1): 558, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34724951

RESUMO

BACKGROUND: To measure the quality of care for lip and oral cavity cancer worldwide using the data from the Global Burden of Disease (GBD) Study 2017. METHODS: After devising four main indices of quality of care for lip and oral cavity cancer using GBD 2017 study's measures, including prevalence, incidence, years of life lost, years lived with disability, and disability-adjusted life years, we utilised principal component analysis (PCA) to determine a component that bears the most proportion of info among the others. This component of the PCA was considered as the Quality-of-Care Index (QCI) for lip and oral cavity cancer. The QCI score was then reported in both men and women worldwide and different countries based on the socio-demographic index (SDI) and World Bank classifications. RESULTS: Between 1990 and 2017, care quality continuously increased globally (from 53.7 to 59.6). In 1990, QCI was higher for men (53.5 for men compared with 50.8 for women), and in 2017 QCI increased for both men and women, albeit a slightly higher rise for women (57.2 for men compared with 59.9 for women). During the same period, age-standardised QCI for lip and oral cavity cancer increased in all regions (classified by SDI and World Bank). Globally, the highest QCI scores were observed in the elderly age group, whereas the least were in the adult age group. Five countries with the least amount of QCIs were all African. In contrast, North American countries, West European countries and Australia had the highest indices. CONCLUSION: The quality of care for lip and oral cavity cancer showed a rise from 1990 to 2017, a promising outcome that supports patient-oriented and preventive treatment policies previously advised in the literature. However, not all countries enjoyed such an increase in the QCI to the same extent. This alarming finding could imply a necessary need for better access to high-quality treatments for lip and oral cavity cancer, especially in central African countries and Afghanistan. More policies with a preventive approach and paying more heed to the early diagnosis, broad insurance coverage, and effective screening programs are recommended worldwide. More focus should also be given to the adulthood age group as they had the least QCI scores globally.


Assuntos
Carga Global da Doença , Neoplasias , Adulto , Idoso , Anos de Vida Ajustados por Deficiência , Detecção Precoce de Câncer , Feminino , Saúde Global , Humanos , Incidência , Lábio , Masculino , Qualidade da Assistência à Saúde , Anos de Vida Ajustados por Qualidade de Vida
13.
Chaos Solitons Fractals ; 140: 110151, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32834639

RESUMO

Coronaviruses are a huge family of viruses that affect neurological, gastrointestinal, hepatic and respiratory systems. The numbers of confirmed cases are increased daily in different countries, especially in Unites State America, Spain, Italy, Germany, China, Iran, South Korea and others. The spread of the COVID-19 has many dangers and needs strict special plans and policies. Therefore, to consider the plans and policies, the predicting and forecasting the future confirmed cases are critical. The time series models are useful to model data that are gathered and indexed by time. Symmetry of error's distribution is an essential condition in classical time series. But there exist cases in the real practical world that assumption of symmetric distribution of the error terms is not satisfactory. In our methodology, the distribution of the error has been considered to be two-piece scale mixtures of normal (TP-SMN). The proposed time series models works well than ordinary Gaussian and symmetry models (especially for COVID-19 datasets), and were fitted initially to the historical COVID-19 datasets. Then, the time series that has the best fit to each of the dataset is selected. Finally, the selected models are applied to predict the number of confirmed cases and the death rate of COVID-19 in the world.

14.
Iran J Pharm Res ; 11(4): 1183-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-24250552

RESUMO

Platelet aggregation inhibitory effect and anticoagulant properties of fractions separated from the venoms of Cerastes persicus fieldi and Echis carinatus were investigated. The partial fractionation was performed on a Sephadex G-100 column. Two fractions separated from Cerastes persicus fieldi showed anti platelet aggregation activity on ADP (200 µM)-induced platelet aggregation (ca 80% inhibition). Attempts to measure the antiplatelet aggregation activity of crude Echis carinatus venom and its fractions were not successful due to the protein coagulation of the plasma samples after the addition of venom. Anticoagulant activities of venoms were also evaluated. Total venom of Echis carinatus showed anti coagulant activity in PT test, while its fractions showed procoagulant activity.

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