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1.
J Urol ; 197(1): 255-261, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27545572

RESUMO

PURPOSE: We evaluated magnetic resonance imaging controlled transurethral ultrasound therapy as a treatment for magnetic resonance imaging defined focal prostate cancer using subsequent prostatectomy and histology as the reference standard. MATERIALS AND METHODS: Five men completed this pilot study, which was approved by the institutional review board. Prior to radical prostatectomy focal tumors identified by magnetic resonance imaging were treated by coagulating targeted subtotal 3-dimensional volumes of prostate tissue using magnetic resonance imaging controlled transurethral focused ultrasound. Treatment was performed with a 3 Tesla clinical magnetic resonance imaging unit combined with modified clinical planning software for high intensity focused ultrasound therapy. After prostatectomy whole mount histological sections parallel to the magnetic resonance imaging treatment planes were used to compare magnetic resonance imaging measurements with thermal damage at the cellular level and, thus, evaluate treatment and target accuracy. RESULTS: Three-dimensional target volumes of 4 to 20 cc and with radii up to 35 mm from the urethra were treated successfully. Mean ± SD temperature control accuracy at the target boundary was -1.6 ± 4.8C and the mean spatial targeting accuracy achieved was -1.5 ± 2.8 mm. Mean treatment accuracy with respect to histology was -0.4 ± 1.7 mm with all index tumors falling inside the histological outer limit of thermal injury. CONCLUSIONS: Magnetic resonance imaging guided transurethral ultrasound therapy is capable of generating thermal coagulation and tumor destruction in targeted 3-dimensional angular sectors out to the prostate capsule for prostate glands up to 70 cc in volume. Ultrasound parameters needed to achieve ablation at the prostate capsule were determined, providing a foundation for future studies.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Cirurgia Assistida por Computador/métodos , Idoso , Biópsia por Agulha , Seguimentos , Humanos , Imageamento Tridimensional , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Cuidados Pré-Operatórios/métodos , Neoplasias da Próstata/patologia , Medição de Risco , Estudos de Amostragem , Fatores de Tempo , Resultado do Tratamento
2.
Magn Reson Med ; 76(2): 702-12, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26493684

RESUMO

PURPOSE: Abdominal MRI remains challenging because of respiratory motion. Motion compensation strategies are difficult to compare clinically because of the variability across human subjects. The goal of this study was to evaluate a programmable system for one-dimensional motion management MRI research. METHODS: A system comprised of a programmable motorized linear stage and computer was assembled and tested in the MRI environment. Tests of the mutual interference between the platform and a whole-body MRI were performed. Organ trajectories generated from a high-temporal resolution scan of a healthy volunteer were used in phantom tests to evaluate the effects of motion on image quality and quantitative MRI measurements. RESULTS: No interference between the motion platform and the MRI was observed, and reliable motion could be produced across a wide range of imaging conditions. Motion-related artifacts commensurate with motion amplitude, frequency, and waveform were observed. T2 measurement of a kidney lesion in an abdominal phantom showed that its value decreased by 67% with physiologic motion, but could be partially recovered with navigator-based motion-compensation. CONCLUSION: The motion platform can produce reliable linear motion within a whole-body MRI. The system can serve as a foundation for a research platform to investigate and develop motion management approaches for MRI. Magn Reson Med 76:702-712, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Artefatos , Leitos , Interpretação de Imagem Assistida por Computador/instrumentação , Imageamento por Ressonância Magnética/instrumentação , Movimento (Física) , Movimento , Posicionamento do Paciente/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Interpretação de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Magn Reson Med ; 74(4): 1095-102, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25310966

RESUMO

PURPOSE: Because existing magnetic resonance thermometry techniques do not provide temperature information within bone, high-intensity focused ultrasound (HIFU) exposures in bone are monitored using temperature changes in adjacent soft tissues. In this study, the potential to monitor temperature changes in cortical bone using a short TE gradient echo sequence is evaluated. METHODS: The feasibility of this proposed method was initially evaluated by measuring the temperature dependence of the gradient echo signal during cooling of cortical bone samples implanted with fiber-optic temperature sensors. A subsequent experiment involved heating a cortical bone sample using a clinical MR-HIFU system. RESULTS: A consistent relationship between temperature change and the change in magnitude signal was observed within and between cortical bone samples. For the two-dimensional gradient echo sequence implemented in this study, a least-squares linear fit determined the percentage change in signal to be (0.90 ± 0.01)%/°C. This relationship was used to estimate temperature changes observed in the HIFU experiment and these temperatures agreed well with those measured from an implanted fiber-optic sensor. CONCLUSION: This method appears capable of displaying changes related to temperature in cortical bone and could improve the safety of MR-HIFU treatments. Further investigations into the sensitivity of the technique in vivo are warranted.


Assuntos
Osso e Ossos/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imageamento por Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador , Termometria/métodos , Animais , Osso e Ossos/fisiologia , Bovinos , Desenho de Equipamento , Estudos de Viabilidade , Ablação por Ultrassom Focalizado de Alta Intensidade/instrumentação , Processamento de Imagem Assistida por Computador , Temperatura
4.
Eur J Pediatr ; 173(11): 1511-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24934631

RESUMO

UNLABELLED: The aim of this study was to analyse the relationship between insulin-glucose metabolism, nocturnal blood pressure dipping and nonalcoholic fatty liver disease (NAFLD) in obese adolescents without diabetes. One hundred one consecutive children, with biopsy-proven NAFLD, were included in this study. Blood samples were drawn for the analyses of liver function tests, insulin-glucose metabolism and lipid profile appraisal. An ambulatory blood pressure measurement (ABPM) was performed. Seventy-six children (75.3 %) were systolic nondippers, and 23 of them were diastolic nondippers (30.3 %). No differences were found in the anthropometric parameters between the two groups. When compared to the systolic dippers, the systolic nondippers had higher medians of mean nocturnal blood pressure, glucose at 0, 60 and 120 min in the oral glucose tolerance test (OGTT), OGTT insulin at all time points and insulin-resistance values. No correlation of histopathological features with dipping/nondipping statuses was found. CONCLUSIONS: We found an association between a nocturnal blood pressure fall and measures of insulin levels, independent of obesity, or daytime blood pressure levels, among the obese patients with NAFLD. Although no association between nondipping profiles and NAFLD was observed in our study, further studies with a longer term follow-up are needed, to better elucidate the complex link between these particular entities.


Assuntos
Pressão Sanguínea/fisiologia , Resistência à Insulina/fisiologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Obesidade Infantil/fisiopatologia , Adolescente , Antropometria , Glicemia , Determinação da Pressão Arterial , Monitorização Ambulatorial da Pressão Arterial , Criança , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Estudos Prospectivos
5.
J Pak Med Assoc ; 59(8): 537-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19757700

RESUMO

OBJECTIVE: To investigate the effect of Zizyphus spina christi leaf hydroalcoholic extract (ZLHE) on the isolated rat aorta. METHODS: The rings of the endothelium intact and denuded thoracic aorta of Male and female Sprague Dawley rats were placed in Krebs-Henseleit solution to measure isometric contractile force. To study the involvement of voltage dependent L type calcium channels, concentration of 10 ?M verapamil was applied. Potassium chloride (50 mM) was also added to the organ bath to compare the effect of extract and KCl. Potassium concentration of the extract at 2.5 and 5 mg/ml was measured. RESULTS: ZLHE induced contraction in the endothelium intact and denuded aorta dose dependently and significantly (P < 0.0001). Also, the response to extract at 5 mg/ml was similar to that of KCl (50 mM). The application of verapamil reduced the contraction in the endothelium intact and denuded aorta by 66.7 +/- 3.1% (mean +/- SEM.) and 71.6 +/- 3.8% respectively. CONCLUSION: The results showed the vasoconstrictive effect of ZLHE which was not endothelium-dependent and largely blocked by verapamil, suggesting that the voltage-dependent Calcium channels play a pivotal role in the mechanism of action.


Assuntos
Aorta Torácica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vasodilatadores/farmacologia , Ziziphus/química , Análise de Variância , Animais , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Feminino , Masculino , Músculo Liso/efeitos dos fármacos , Folhas de Planta/química , Ratos , Ratos Sprague-Dawley , Vasoconstrição/efeitos dos fármacos , Verapamil/farmacologia
6.
Med Phys ; 43(1): 241, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26745917

RESUMO

PURPOSE: Magnetic resonance imaging (MRI) is capable of providing valuable real-time feedback during medical procedures, partly due to the excellent soft-tissue contrast available. Several technical hurdles still exist to seamless integration of medical devices with MRI due to incompatibility of most conventional devices with this imaging modality. In this study, the effect of local perturbations in the magnetic field caused by the magnetization of medical devices was examined using finite element analysis modeling. As an example, the influence of the geometric and material characteristics of a transurethral high-intensity ultrasound applicator on temperature measurements using proton resonance frequency (PRF)-shift thermometry was investigated. METHODS: The effect of local perturbations in the magnetic field, caused by the magnetization of medical device components, was examined using finite element analysis modeling. The thermometry artifact generated by a transurethral ultrasound applicator was simulated, and these results were validated against analytic models and scans of an applicator in a phantom. Several parameters were then varied to identify which most strongly impacted the level of simulated thermometry artifact, which varies as the applicator moves over the course of an ablative high-intensity ultrasound treatment. RESULTS: Key design parameters identified as having a strong influence on the magnitude of thermometry artifact included the susceptibility of materials and their volume. The location of components was also important, particularly when positioned to maximize symmetry of the device. Finally, the location of component edges and the inclination of the device relative to the magnetic field were also found to be important factors. CONCLUSIONS: Previous design strategies to minimize thermometry artifact were validated, and novel design strategies were identified that substantially reduce PRF-shift thermometry artifacts for a variety of device orientations. These new strategies are being incorporated into the next generation of applicators. The general strategy described in this study can be applied to the design of other interventional devices intended for use with MRI.


Assuntos
Imageamento por Ressonância Magnética/instrumentação , Termometria/instrumentação , Artefatos , Humanos , Imagens de Fantasmas
7.
Asian Pac J Cancer Prev ; 15(1): 441-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24528071

RESUMO

BACKGROUND: Multi-state models are appropriate for cancer studies such as gastrectomy which have high mortality statistics. These models can be used to better describe the natural disease process. But reaching that goal requires making assumptions like Markov and homogeneity with time. The present study aims to investigate these hypotheses. MATERIALS AND METHODS: Data from 330 patients with gastric cancer undergoing surgery at Iran Cancer Institute from 1995 to 1999 were analyzed. To assess Markov assumption and time homogeneity in modeling transition rates among states of multi-state model, Cox-Snell residuals, Akaikie information criteria and Schoenfeld residuals were used, respectively. RESULTS: The assessment of Markov assumption based on Cox-Snell residuals and Akaikie information criterion showed that Markov assumption was not held just for transition rate of relapse (state 1-state 2) and for other transition rates - death hazard without relapse (state 1-state 3) and death hazard with relapse (state 2-state 3) - this assumption could also be made. Moreover, the assessment of time homogeneity assumption based on Schoenfeld residuals revealed that this assumption - regarding the general test and each of the variables in the model - was held just for relapse (state 1-state 2) and death hazard with a relapse (state 2-state 3). CONCLUSIONS: Most researchers take account of assumptions such as Markov and time homogeneity in modeling transition rates. These assumptions can make the multi-state model simpler but if these assumptions are not made, they will lead to incorrect inferences and improper fitting.


Assuntos
Modelos Estatísticos , Recidiva Local de Neoplasia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Análise de Sobrevida , Humanos , Irã (Geográfico) , Cadeias de Markov , Prognóstico , Medição de Risco/métodos , Tempo
8.
J Reprod Infertil ; 10(3): 213-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23926471

RESUMO

INTRODUCTION: This article compares the prevalence of primary infertility in Iran estimates provided by different studies. No other study had provided a review about the researches related to epidemiology of infertility in the country. MATERIALS AND METHODS: A literature review was undertaken using the scientific resources on the internet and the list of national projects obtained from Deputy of Research and Technology, of Iran Ministry of Health and Medical Education (MOH & ME) and relevant research centers. These resources were attentively reviewed to find about national studies on the epidemiology of primary infertility in Iran during the last decade. Based on their design quality, the National Infertility Study (NIS) (2004-2005), National Health Survey (NHS) (2001) and Tehran Study (1997) were considered for the research. RESULTS: Current primary infertility estimated by National Health Survey (NHS) was 2.8% and by National Infertility Survey (NIS) 3.4%. Tehran study and NIS estimated the prevalence of lifetime primary infertility to be 21.9% and 24.9%, respectively. The minimum prevalence of lifetime primary infertility was found to be 15.8% for the marriage age of 19-27 by Tehran study and 17.2% for the marriage age of 21-26 by NIS. CONCLUSION: On the average, 21-22% of women experience primary infertility during their marital life. The best age of marriage for women in Iran seems to be 20-27 years. At this age group, the lowest number of women (16-18%) would experience primary infertility.

9.
Singap. med. j ; Singap. med. j;: 336-343, 2012.
Artigo em Inglês | WPRIM | ID: wpr-334488

RESUMO

<p><b>INTRODUCTION</b>Oesophageal cancer is one of the most common causes of cancer mortality in developing countries, including Iran. This study aimed to assess factors affecting survival of patients with oesophageal cancer using parametric analysis with frailty models.</p><p><b>METHODS</b>Data on 359 patients with oesophageal cancer was collected from the Babol Cancer Registry for the period 1990-1991. By 2006, the patients had been followed up for a period of 15 years. Hazard ratio was used to interpret the risk of death. To explore factors affecting the survival of patients, log-normal and log-logistic models with frailty were examined. The Akaike Information Criterion (AIC) was used for selecting the best model(s). Cox regression was not suitable for this patient group, as the proportionality assumption of the Cox model was not satisfied by our data (p = 0.007).</p><p><b>RESULTS</b>Multivariate analysis according to parametric models showed that family history of cancer might increase the risk of death from cancer significantly. Based on AIC scores, the log-logistic model with inverse Gaussian frailty seemed more appropriate for our data set, and we propose that the model might prove to be a useful statistical model for the survival analysis of patients with oesophageal cancer. The results suggested that gender and family history of cancer were significant predictors of death from cancer.</p><p><b>CONCLUSION</b>Early preventative care for patients with a family history of cancer may be important to decrease the risk of death in patients with oesophageal cancer. Male gender may be associated with a lower risk of death.</p>


Assuntos
Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países em Desenvolvimento , Neoplasias Esofágicas , Mortalidade , Seguimentos , Irã (Geográfico) , Epidemiologia , Modelos Estatísticos , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
10.
IJFS-International Journal of Fertility and Sterility. 2017; 11 (2): 117-122
em Inglês | IMEMR | ID: emr-186839

RESUMO

Background: The most common chromosomal abnormality due to non-obstructive azoospermia [NOA] is Klinefelter syndrome [KS] which occurs in 1-1.72 out of 500-1000 male infants. The probability of retrieving sperm as the outcome could be asymmetrically different between patients with and without KS, therefore logistic regression analysis is not a well-qualified test for this type of data. This study has been designed to evaluate skewed regression model analysis for data collected from microsurgical testicular sperm extraction [micro-TESE] among azoospermic patients with and without non-mosaic KS syndrome


Materials and Methods: This cohort study compared the micro-TESE outcome between 134 men with classic KS and 537 men with NOA and normal karyotype who were referred to Royan Institute between 2009 and 2011. In addition to our main outcome, which was sperm retrieval, we also used logistic and skewed regression analyses to compare the following demographic and hormonal factors: age, level of follicle stimulating hormone [FSH], luteinizing hormone [LH], and testosterone between the two groups


Results: A comparison of the micro-TESE between the KS and control groups showed a success rate of 28.4% [38/134] for the KS group and 22.2% [119/537] for the control group. In the KS group, a significantly difference [P<0.001] existed between testosterone levels for the successful sperm retrieval group [3.4 +/- 0.48 mg/mL] compared to the unsuccessful sperm retrieval group [2.33 +/- 0.23 mg/mL]. The index for quasi Akaike information criterion [QAIC] had a goodness of fit of 74 for the skewed model which was lower than logistic regression [QAIC=85]


Conclusion: According to the results, skewed regression is more efficient in estimating sperm retrieval success when the data from patients with KS are analyzed. This finding should be investigated by conducting additional studies with different data structures

11.
Journal of Reproduction and Infertility. 2016; 17 (2): 68-81
em Inglês | IMEMR | ID: emr-178809

RESUMO

Background: Infertile couples are faced with problems that affect their marital life. Infertility treatment is expensive and time consuming and occasionally isn't simply possible. Prediction models for infertility treatment have been proposed and prediction of treatment success is a new field in infertility treatment. Because prediction of treatment success is a new need for infertile couples, this paper reviewed previous studies for catching a general concept in applicability of the models


Methods: This study was conducted as a systematic review at Avicenna Research Institute in 2015. Six data bases were searched based on WHO definitions and MESH key words. Papers about prediction models in infertility were evaluated


Results: Eighty one papers were eligible for the study. Papers covered years after 1986 and studies were designed retrospectively and prospectively. IVF prediction models have more shares in papers. Most common predictors were age, duration of infertility, ovarian and tubal problems


Conclusion: Prediction model can be clinically applied if the model can be statistically evaluated and has a good validation for treatment success. To achieve better results, the physician and the couples' needs estimation for treatment success rate were based on history, the examination and clinical tests. Models must be checked for theoretical approach and appropriate validation. The privileges for applying the prediction models are the decrease in the cost and time, avoiding painful treatment of patients, assessment of treatment approach for physicians and decision making for health managers. The selection of the approach for designing and using these models is inevitable


Assuntos
Humanos , Previsões , Terapêutica
12.
Journal of Tehran University Heart Center [The]. 2016; 11 (2): 55-61
em Inglês | IMEMR | ID: emr-192901

RESUMO

Background: Investigators frequently encounter continuous outcomes with plenty of values clumped at zero called semi-continuous outcomes. The Gensini score, one of the most widely used scoring systems for expressing coronary angiographic results, is of this type. The aim of this study was to apply two statistical approaches based on the categorization and original scale of the Gensini score to simultaneously assess the association between covariates and the presence and severity of coronary artery disease [CAD]


Methods: We considered the data on 1594 individuals admitted to Tehran Heart Center with CAD symptoms from July 2004 to February 2008. The participants' baseline demographic and clinical characteristics were collected, and their coronary angiographic results were expressed through the Gensini score. The generalized ordinal threshold and two-part models were applied for the statistical analyses


Results: Totally, 320 [20.1%] individuals had a Gensini score of zero. The results of neither the two-part model nor the generalized ordinal threshold model showed a significant association between Factor V Leiden and the occurrence of CAD. However, based on the two-part model, Factor V Leiden was associated with the severity of CAD, such that the Gensini score increased by moving from a wild genotype to a heterozygote [beta = 0.44; 95% CI: 0.20-0.69 in logarithm scale] or a homozygote mutant [beta = 0.70; 95% CI: 0.28- 1.12 in logarithm scale]. The proportional odds assumption was not met in our data [= 54.26; p value < 0.001]; however, a trend toward severe CAD was also observed at each category of the Gensini score using the generalized ordinal threshold model


Conclusion: We conclude that besides loss of information by sorting a semi-continuous outcome, violation from the proportional odds assumption complicates the final decision, especially for clinicians. Therefore, more straightforward models such as the two-part model should receive more attention while analyzing such outcomes

13.
Iranian Journal of Public Health. 2014; 43 (9): 1239-1247
em Inglês | IMEMR | ID: emr-152957

RESUMO

The aim of this study was to determine the socioeconomic inequalities in nonuse of seatbelts in cars and helmets on motorcycles in Kurdistan Province, west of Iran, 2009. The data used in this study was collected from the data gathered in non-communicable disease surveillance system [NCDSS] in 2009 in Kurdistan. A total of 1000 people were included in this study. The outcome variable of this study was the nonuse of seatbelts and helmets. The socio-economic status [SES] was calculated based on participants' residential area and assets using Principal Component Analysis [PCA] method. The concentration index, concentration curve, and comparison of Odds Ratio [OR] in different SES groups were used to measure the socioeconomic inequalities using logistic regression. In order to determine the contribution of determinants of inequality, decomposition analysis was used. The prevalence of nonuse of seatbelts in cars and helmets on motorcycles were 47.5%, 95%CI [44%, 55%], respectively. The Concentration index was -0.097, CI [-0.148, -0.046]. The OR of nonuse of seatbelts in cars and helmets on motorcycles in the richest group compared with the poorest group was 0.39, 95%CI [0.23, 0.68]. The results of the decomposition analysis showed that 34% of inequalities were due to SES, 47% were due to residential area, and 12% were due to unknown factors. There is a reverse association between SES and nonuse of seatbelts in cars and helmets on motorcycles. This issue must be considered while planning to reduce traffic accidents injuries

14.
Iranian Journal of Public Health. 2014; 43 (9): 1248-1258
em Inglês | IMEMR | ID: emr-152958

RESUMO

The aim of this study was to determine adherence and attrition rates in a lifestyle intervention for people with metabolic syndrome. Adherence and attrition data from a randomized controlled trial were collected. Participants were classified as adherence group if they completed assessments at 3 and 6 months follow-up and as attrition group if they did not. Physical activity and quality of life was measured using the International Physical Activity Questionnaire [IPAQ] and the Short Form Health Survey [SF-36]. Generalized Estimating Equations [GEE] was used to explore predictors of attrition. The mean age of participants [n=160] was 44.1 years. Attrition rate in the intervention and control groups at first follow-up were the same [20%]. However, the control group had significantly higher attrition rate [%33.7] compared to the intervention group [%20] at 6 months follow up. Results showed that low educated participants were more likely to not stay in the study than better educated participants [OR=2.95,CI:1.39-6.33,P=0.05]. According with length of the study, attrition was decreased at six month [OR=0.66,CI:0.52-0.83,P<0.001]. Also, some aspects of health-related quality of life contributed to the attrition rate. Those who had higher scores on general health [OR=0.66,CI:0.54-0.97,P=0.023], social functioning [OR=0.44,CI:0.40-0.76,P=0.032], role emotional [OR=0.74,CI:0.54-0.98,P=0.18], vitality [OR=0.55,CI:0.38-0.90,P=0.015] and mental health [OR=0.63,CI:0.45-0.85,P=0.033] were more likely to stay in the study. It remains a concern that Web-based lifestyle programs may fail to reach those who need it most. Participant in the study generally had better quality of life than those who were lost to follow up

15.
Iranian Journal of Public Health. 2014; 43 (8): 1079-1090
em Inglês | IMEMR | ID: emr-152978

RESUMO

Network scale-up is an indirect method for estimating the size of hidden, hard-to-count or high risk populations. Social network size estimation is the first step in this method. The present study was conducted with the purpose of estimating the social network size of the Tehran Province residents and its determinants. Maximum Likelihood Estimation was applied to estimate people's network sizes by using populations of known sizes and the scale-up method. Respondents were selected from Tehran province through convenience sampling in 2012. Out of thirteen selected subpopulations with known size, ten had minimum accuracy which used in our analysis. Of the 1029 respondents in this study, 46.7% were male. The social network size of Tehran Province residents was estimated to be 259.1 [CI[95%]: 242.2, 276] based on the ten known populations remained in this study. This size was 291.8 in men and 230.4 in women. Younger people [18-25 years old] had larger network sizes compared to the other age groups [P<0.001]. Our estimation for social network size of Tehran inhabitants was smaller than that previously estimated size for the whole country [c=380]. In addition, we found that the social network of subpopulations was different. This difference means that we need local estimations for sub-populations to improve the accuracy of population size estimation using network scale up method

16.
IJPM-International Journal of Preventive Medicine. 2014; 5 (5): 624-631
em Inglês | IMEMR | ID: emr-147054

RESUMO

Maternal mortality ratio [MMR] is one of the main indicators of the millennium development goals and its accurate estimation is very important for the countries concerned. The objective of this study is to evaluate the applicability of capture-recapture [CRC] as an analytical method to estimate MMR in countries. We used the CRC method to estimate MMR in Iran for 2004 and 2005, using two data sources: The maternal mortality surveillance system and the National Death Registry [NDR]. Because the data registry contains errors, we defined three levels of matching criteria to enable matching of cases between the two systems. Increasing the matching level makes the matching criteria less conservative. Because NDR data were missing or incomplete for some provinces, we calculated estimates for two conditions: With and without missing/incomplete data. According to the CRC method, MMR in 2004 and 2005 were 33 and 25 in the best-case scenarios respectively and 86 and 59 in the worst-case scenarios respectively. These estimates are closer to the ones reported by United Nations Agencies published in 2010, 38 and Hogan's study, 30 in 100,000 live births in 2005. The MMR estimation by CRC method is slightly different from the international studies. CRC can be considered as a cost-effective method, in comparison with cross-sectional studies or improvement of vital registration systems, which are both costly and difficult. However, to achieve accurate estimates of MMR with CRC method and decrease the uncertainty we need to have valid databases and the absence of such capacities will limit the applicability of this method in developing countries with poor quality health databases

17.
Journal of Research in Health Sciences [JRHS]. 2014; 14 (4): 303-307
em Inglês | IMEMR | ID: emr-154075

RESUMO

Lifestyle is recognized as a key factor as the cause and management of the metabolic syndrome. The aim of this study was to identify individuals at increased cardiovascular diseases risk and determine main features of lifestyle of participants with metabolic syndrome via internet. The study was conducted from Jun 22 to August 22, 2012 in Tehran, Iran. Recruitment was carried out through the study website. Participants with metabolic syndrome who were interested and met the study criteria were invited for free clinic visits and clinical assessments. Baseline measurements were metabolic syndrome risk factors. Physical activity and dietary intake were measured by international physical activity questionnaire [IPAQ- short form] and the frequency food questionnaire [FFQ] respectively. Metabolic syndrome was defined according to Adult Treatment Panel III diagnostic criteria. Mean [SD] age for men and women were 41.9 [10.4] and 48.1 [7.8] yr respectively. Men were well educated and more likely to participate in the study than women. Men with metabolic syndrome had larger waist circumference [105.5] and lower BMI [29.1] than women with metabolic syndrome [P<0.001]. Approximately 73% of the sample was inactive and 3% of participants had health enhancing physical activity. There were significant differences in the intakes of total fat and cholesterol between men and women [P<0.001]. Because of the high prevalence of metabolic syndrome, national lifestyle modification policies must be developed for population. Web-based healthy lifestyle programs may contribute to the reduction of the metabolic syndrome components


Assuntos
Humanos , Masculino , Feminino , Estilo de Vida , Fatores de Risco , Internet , Atividade Motora , Ingestão de Alimentos , Dieta
18.
Iranian Journal of Public Health. 2014; 43 (6): 800-808
em Inglês | IMEMR | ID: emr-167598

RESUMO

Gastric cancer is the most prevalent cancer among men and the third most prevalent cancer among women in Iran. Its most important reason for death is its belated diagnosis at the advanced stages of the disease. Various factors can be effective on the survival of these patients after surgery, which are the major concern in this study. Data from 330 patients with Gastric cancer who had undergone surgery at Iran Cancer Institute from 1995 to 1999 were analyzed. The Survival Time of patients was determined after surgery and the effect of individual and demographic; clinical and diagnostic; and treatment and post-surgical factors on patients' survival was studied. For data analysis, Kaplan- Meier, Log-Rank test and Proportional Hazards Model were used. The median of survival time was 16.33 months. The one-year, three-year, and five-year survival rates were, 0.66, 0.31, and 0.21. Based on univariate analysis results of age[P<0.001], metastases[P=0.012], disease stage[P=0.016], and number of renewed treatments[P<0.001], as well as multivariate analysis which was used to investigate the simultaneous effect of influencing variables on patients' survival showed that age[61-70:HR=1.40,>70:HR=2.08], marital status[HR=0.39], number of renewed treatments[1:HR=0.54,2:HR=0.30,3:HR=0.22], relapse[HR=1.51], type of gastrectomy [Subtotal: HR=1.12, Distal:HR=0.49, Partial:HR=0.94, Proximal:HR=0.52], liver metastases [HR=1.79], distance metastases[HR=1.84], and disease stage[II:HR=1.28,III:HR=2.12,IV:HR=1.90] variables had a significant effect on patients' survival. Patients who call on doctors in early stages of disease will have a higher survival rate due to early diagnosis whereas disease progression will increase the risk and will decrease the survival. Identifying factors affecting patients' survival and improving diagnostic methods can prevent disease progression and increase survival rate


Assuntos
Humanos , Masculino , Feminino , Taxa de Sobrevida
19.
Acta Medica Iranica. 2014; 52 (5): 341-344
em Inglês | IMEMR | ID: emr-159579

RESUMO

Currently, laparoscopic cystectomy is the first-line therapy for ovarian benign cysts that are resistant to current therapies. There are different studies that point to ovarian reserve damage due to laparoscopic cystectomy. In this study, we evaluate the ovarian damage following laparoscopic cystectomy for non-endometriosis cysts using ultrasound and pathology findings. This is a prospective cohort study conducted between 7rd month of 2011 and 10th month of 2012 in Women hospital affiliated to Tehran university of medical sciences.45 non-endometriosis cysts [17 teratoma,7 mucinous, 10 simple serous and 11 simple cysts] underwent laparoscopic cystectomy with stripping technique. Amount of excised parenchyma, number of lost oocytes and cyst wall fibrosis thickness were histopathologically studied. Before and 3 months after surgery antral follicle count was evaluated by ultrasound. AFC after cystectomy for teratoma and simple serous was significantly reduced P<0.05. By larger teratomas and more parenchyma inadvertently removed during their excision [1.64, 0.255] reduced AFC was seen and in simple serous cysts with more removed parenchyma amount [1.5] reduced AFC occurred. In our study simple cysts excision led to a loss in AFC that was not associated with any other cyst parameters. Mucinous cysts resection led to no specific ovarian reserve damage. Laparoscopic cystectomy for non-endometriosis leads to reduced ovarian reserve

20.
Iranian Journal of Public Health. 2014; 43 (3): 316-322
em Inglês | IMEMR | ID: emr-159618

RESUMO

Renal transplantation is a therapy for end-stage renal disease. During the study of recipients' survival after renal transplantation, there are some events as intermediate events that not only affect the recipients' survival but also events which are affected by various factors. The aim of this study was to handle these intermediate events in order to identify factors that affect recipients' survival by using multi-state models. This retrospective cohort study included 405 renal transplant patients from Afzalipour Hospital, Kerman, Iran, from 2004 to 2010. The survival time of these recipients was determined after transplantation and the effect of various factors on the death hazard with and without renal allograft failure and hazard of renal allograft failure was studied by using multistate models. During 4.06 years [median] of follow-up; 28 [6.9%] recipients died and allograft failure occurred in 51 [12.6%] recipients. Based on the results of multi-state model, receiving a living kidney transplantation decreased the hazard of renal allograft failure [HR=0.38; 95% CI: 0.17- 0.87], pre-transplant hypertension [HR=2.94; 95% CI: 1.54- 5.63] and serum creatinine levels >1.6 upon discharge from the hospital [HR=7.38; 95% CI: 3.87- 7.08] increased the hazard of renal allograft failure. Receiving living kidney transplantation decreased the hazard of death directly [HR=0.18; 95% CI: 0.04- 0.93]. It was concluded that the effect of donor type, pre-transplant hypertension and having serum creatinine >1.6 upon discharge from the hospital was significant on hazard of renal allograft failure. The only variable that had a direct significant effect on hazard of death was donor type

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