Unveiling the global nexus: Pandemic fear, government responses, and climate change-an empirical study.

This study examined the relationships between pandemic fear, government responses, and climate change using a time-series dataset from January 1, 2020, to December 31, 2020. By employing an auto-regressive distributed lag (ARDL) approach, the results revealed that pandemic fear significantly impacts climate change, while government responses to COVID-19 negatively influence climate change in the long run. Climate change and government responses significantly positively affect pandemic fear in the long run. Moreover, we found a bidirectional causality between government responses and climate change, unidirectional causality from government responses to pandemic fear, and no Granger causality between pandemic fear and climate change. Our findings have some important policy implications. Governments must encourage coordination, enhance crisis responses, and consider revising economic metrics to maintain environmental sustainability. The COVID-19 experience can inform strategies for reducing CO2 emissions and investing in green economies and healthcare to prepare for future challenges.

Effects of Growth Factors on In Vitro Culture of Neonatal Piglet Testicular Tissue Fragments.

In vitro spermatogenesis (IVS) has important applications including fertility preservation of prepubertal cancer patients; however, thus far, IVS has only been achieved using mouse models. To study the effects of growth factors on the maintenance of testicular tissue integrity, germ cell numbers, and potential induction of IVS using a porcine model, we cultured small testicular fragments (~2 mg) from 1-wk-old piglets under six different media conditions (DMEM + 10%KSR alone or supplemented with GDNF, bFGF, SCF, EGF, or a combination of all) for 8 weeks. Overall, tissues supplemented with GDNF and bFGF had the greatest seminiferous tubule integrity and least number of apoptotic cells. GDNF-supplemented tissues had the greatest number of gonocytes per tubule, followed by bFGF-supplemented tissues. There was evidence of gradual Sertoli cell maturation in all groups. Moreover, histological examination and the expression of c-KIT (a marker of differentiating spermatogonia and spermatocytes) and STRA8 (a marker of the pre/meiotic stage germ cells) confirmed the induction of IVS in all groups. However, GDNF- and bFGF-supplemented tissue cultures had greater numbers of seminiferous tubules with spermatocytes compared to other groups. In conclusion, overall, GDNF and bFGF supplementation better maintained the tissue integrity and gonocyte numbers and induced IVS in cultured testicular tissues.

The lock-down effects of COVID-19 on the air pollution indices in Iran and its neighbors.

Introduction: The COVID-19 restrictions have a lot of various peripheral negative and positive effects, like economic shocks and decreasing air pollution, respectively. Many studies showed NO2 reduction in most parts of the world. Methods: Iran and its land and maritime neighbors have about 7.4% of the world population and 6.3% and 5.8% of World COVID-19 cases and deaths, respectively. The air pollution indices of them such as CH4 (Methane), CO_1 (CO), H2O (Water), HCHO (Tropospheric Atmospheric Formaldehyde), NO2 (Nitrogen oxides), O3 (ozone), SO2 (Sulfur Dioxide), UVAI_AAI [UV Aerosol Index (UVAI)/Absorbing Aerosol Index (AAI)] are studied from the First quarter of 2019 to the fourth quarter of 2021 with Copernicus Sentinel 5 Precursor (S5P) satellite data set from Google Earth Engine. The outliers are detected based on the depth functions. We use a two-sample t test, Wilcoxon test, and interval-wise testing for functional data to control the familywise error rate. Result: The adjusted p value comparison between Q2 of 2019 and Q2 of 2020 in NO2 for almost all countries is statistically significant except Iraq, UAE, Bahrain, Qatar, and Kuwait. But, the CO and HCHO are not statistically significant in any country. Although CH4, O3, and UVAI_AAI are statistically significant for some countries. In the Q2 comparison for NO2 between 2020 and 2021, only Iran, Armenia, Turkey, UAE, and Saudi Arabia are statistically significant. However, Ch4 is statistically significant for all countries except Azerbaijan. Conclusions: The comparison with and without adjusted p values declares the decreases in some air pollution in these countries. Supplementary Information: The online version contains supplementary material available at 10.1007/s40808-022-01528-x.

Using a testis regeneration model, FGF9, LIF, and SCF improve testis cord formation while RA enhances gonocyte survival.

Implantation of testis cell aggregates from various donors under the back skin of recipient mice results in de novo formation of testis tissue. We used this implantation model to study the putative in vivo effects of six different growth factors on testis cord development. Recipient mice (n = 7/group) were implanted with eight neonatal porcine testis cell aggregates that were first exposed to a designated growth factor: FGF2 at 1 µg/mL, FGF9 at 5 µg/mL, VEGF at 3.5 µg/mL, LIF at 5 µg/mL, SCF at 3.5 µg/mL, retinoic acid (RA) at 3.5 × 10-5 M, or no growth factors (control). The newly developed seminiferous cords (SC) were classified based on their morphology into regular, irregular, enlarged, or aberrant. Certain treatments enhanced implant weight (LIF), implant cross-sectional area (SCF) or the relative cross-sectional area covered by SC within implants (FGF2). RA promoted the formation of enlarged SC and FGF2 led to the highest ratio of regular SC and the lowest ratio of aberrant SC. Rete testis-like structures appeared earlier in implants treated with FGF2, FGF9, or LIF. These results show that even brief pre-implantation exposure of testis cells to these growth factors can have profound effects on morphogenesis of testis cords using this implantation model.

Culture media and supplements affect proliferation, colony-formation, and potency of porcine male germ cells.

Gonocytes are germline stem cells in the neonatal testis with important potential applications in fertility restoration and transgenesis. Using stepwise experiments, we examined the effects of different media combined with fetal bovine serum (FBS) and/or knockout serum replacement (KSR) on the in vitro proliferation, colony-formation, ultrastructure, and expression of pluripotency markers of porcine gonocytes. Testis cells from 1-wk-old piglets were cultured for 28 days in 6 different culture media (DMEM, DMEM/F12, GMEM, α-MEM, StemPro, and RPMI), each supplemented with 5%, 10%, or 15% FBS and/or 5%, 10%, or 15% KSR. The media and FBS/KSR combination leading to the maximum number of gonocytes, and their colonies were selected for further analyses. KSR supplementation resulted in a reduced somatic cell propagation and increased gonocyte colony formation (P < 0.001). Culturing in DMEM+15%FBS led to the greatest number of gonocytes (P < 0.001), while the largest diameter and greatest number of colonies were formed in DMEM+5%FBS+10%KSR cultures (P < 0.001). Gonocytes and their colonies in DMEM+15%FBS expressed all the examined gonocyte and pluripotency markers. KSR alone did not support gonocyte propagation, likely due to a reduced somatic cell proliferation; however, the combination of FBS and KSR increased gonocyte colony formation and their size.

Brief exposure of neonatal testis cells to EGF or GDNF alters the regenerated tissue.

We have previously shown that implantation of testis cell aggregates under the back skin of immunodeficient mice results in de novo regeneration of testis tissue. We used this unique model to investigate the effects of epidermal growth factor (EGF) and glial cell-derived neurotrophic factor (GDNF) on testis cord development. Neonatal piglet testis cells were briefly (<1 h) exposed to either low (L: 0.02 µg/mL) or high (H: 2 µg/mL) doses of EGF, GDNF, or vehicle (control), before implantation in recipient mice. Randomly selected implants were removed from each mouse at 1, 2, 4, and 8 weeks post-implantation. GDNF-L implants showed increased testis cord development over time, and EGF-L implants had increased cross-sectional area. The ratio of regular cords decreased over time in EGF-H and GDNF-H implants and was replaced by a higher ratio of irregular cords in GDNF-H. EGF-L and GDNF-H implants were quickest to display rete testis-like structures. Overall, the lower dose of each growth factor was more effective than its higher dose in improving the implantation outcomes. This is the first comprehensive assessment of these key growth factors on de novo formation (regeneration) of testis tissue. Lay summary: In recent decades, testicular cancer rates have quadrupled in young men while sperm counts have dropped by half. Both conditions may be related to exposure of fetuses or infants to noxious substances causing disruption of normal testis development. To study the effects of any putative factor on testis development, we established an animal model of testis tissue regeneration. We collected newborn piglet testes after routine castration, used enzymes to completely dissociate testis cells, exposed the cells to two key growth factors (EGF or GDNF), and implanted the cells under the back skin of recipient mice, acting as live incubators. We then examined implant samples after 1, 2, 4, or 8 weeks and assessed testis regeneration. Overall, the high dose of each growth factor had adverse effects on the formation of normal testis. Therefore, this novel implantation model may also be used to study the effects of potentially harmful substances on testis development.

Culture supplementation of bFGF, GDNF, and LIF alters in vitro proliferation, colony formation, and pluripotency of neonatal porcine germ cells.

Gonocytes in the neonatal testis have male germline stem cell properties and as such have important potential applications in fertility preservation and regenerative medicine. Such applications require further studies aimed at increasing gonocyte numbers and evaluating their pluripotency in vitro. The objective of the present study was to test the effects of basic fibroblast growth factor (bFGF), glial cell line-derived neurotrophic factor (GDNF), and leukemia inhibitory factor (LIF) on in vitro propagation, colony formation, and expression of pluripotency markers of neonatal porcine gonocytes. Testis cells from 1-week-old piglets were cultured in basic media (DMEM + 15% FBS), supplemented with various concentrations of bFGF, GDNF, and LIF, either individually or in combinations, in a stepwise experimental design. Gonocytes and/or their colonies were evaluated every 7 days and the gonocyte- (DBA) and pluripotency-specific markers (POU5F1, SSEA-1, E-cadherin, and NANOG) assessed on day 28. Greatest gonocyte numbers and largest colonies were found in media supplemented with 10 ng/mL bFGF and 10 ng/mL bFGF + 100 ng/mL GDNF + 1500 U/mL LIF, respectively. The resultant gonocytes and colonies expressed both germ cell- and pluripotency-specific markers. These results shed light on the growth hormone requirements of porcine gonocytes for in vitro proliferation and colony formation.

Wet-cupping on calf muscles in polycystic ovary syndrome: a quasi-experimental study.

OBJECTIVES: Current modalities for treating polycystic ovary syndrome (PCOS) are not curative and using them for a long period is associated with adverse effects. According to Persian Medicine recommendations, wet cupping on calf muscles can induce menstrual bleeding. In the present study, the effect of wet-cupping (traditional bleeding from capillary vessels) was assessed on menstrual cycles (as primary outcome), hirsutism, and laboratory manifestation of PCOS. METHODS: A quasi-experimental study was conducted from 2016/5/21 until 2017/5/20 on 66 PCOS women within the age range of 20-40 years and a menstrual interval of at least 60 days during the last year. Participants' calf muscles were cupped on day 26 of their last menstruation cycle following the Persian Medicine recommendations. They were followed for 12 weeks and a menstruation history and physical examination was done twice (4 and 12 weeks after wet cupping). Insulin Resistance (IR) and Free Androgen Index (FAI) were evaluated at baseline and end of the study. RESULTS: Wet-cupping on calf muscles significantly improved menstrual cycles' frequency 0.37(95% CI: 0.13, 0.51), p-value=0.001 and hirsutism after 4 and 12 weeks of intervention were -1.9 (95% CI: -2.5, -0.5), p-value<0.001 and -1.4(95% CI: -2.1, -0.8), p-value<0.001, respectively. While it was not significant in changing the IR and FAI. About 33% of participants suffered from mild temporary discomforts (which were resolved within a few minutes of rest) and 9% reported mild long-term side effects. CONCLUSIONS: It is considered that wet-cupping on calf muscles can be propounded as an optional treatment of PCOS for those not willing to use chemical medication.

Long-Term In Vitro Maintenance of Piglet Testicular Tissue: Effects of Tissue Fragment Size, Preparation Method, and Serum Source.

Long-term culture of testicular tissue has important applications, including the preservation of fertility potential of prepubertal boys undergoing gonadotoxic cancer treatment. This study was designed to define optimal conditions for the long-term culture of neonatal porcine testicular tissue as an animal model for preadolescent individuals. Testes from 1 wk old donor piglets were used to examine the effects of tissue fragment size (~2, 4, 6, or 8 mg), preparation method (intact, semi-digested, or physically dispersed fragments), and serum source in the media (fetal bovine serum­FBS­or knockout serum replacement­KSR). Testicular fragments were examined weekly for 4 weeks for tissue integrity, seminiferous cord density and morphology, and gonocyte counts. Testicular tissue integrity was dependent on fragment size and preparation method, where the smallest size (2 mg, p < 0.05) and intact preparation method were advantageous (p < 0.05). Seminiferous cord density decreased over the culture period (p < 0.05). Although the relative number of gonocytes decreased over time for all sizes and methods (p < 0.01), smaller intact fragments (2 and 4 mg) had greater numbers of gonocytes (p < 0.05). Our findings suggest that intact or physically dispersed testicular fragments of the smallest size (2 mg) cultured in KSR-supplemented media could be effectively maintained in vitro for the duration of 4 weeks.

Neonatal Porcine Germ Cells Dedifferentiate and Display Osteogenic and Pluripotency Properties.

Gonocytes are progenitors of spermatogonial stem cells in the neonatal testis. We have previously shown that upon culturing, neonatal porcine gonocytes and their colonies express germ cell and pluripotency markers. The objectives of present study were to investigate in vitro trans-differentiation potential of porcine gonocytes and their colonies into cells from three germinal layers, and to assess pluripotency of cultured gonocytes/colonies in vivo. For osteogenic and tri-lineage differentiation, cells were incubated in regular culture media for 14 and 28 days, respectively. Cells were cultured for an additional 14 days for osteogenic differentiation or 7 days for differentiation into derivates of the three germinal layers. Osteogenic differentiation of cells and colonies was verified by Alizarin Red S staining and tri-lineage differentiation was confirmed using immunofluorescence and gene expression analyses. Furthermore, upon implantation into recipient mice, the cultured cells/colonies developed teratomas expressing markers of all three germinal layers. Successful osteogenic differentiation from porcine germ cells has important implications for bone regeneration and matrix formation studies. Hence, gonocytes emerge as a promising source of adult pluripotent stem cells due to the ability to differentiate into all germinal layers without typical biosafety risks associated with viral vectors or ethical implications.

Generation of a Highly Biomimetic Organoid, Including Vasculature, Resembling the Native Immature Testis Tissue.

The creation of a testis organoid (artificial testis tissue) with sufficient resemblance to the complex form and function of the innate testis remains challenging, especially using non-rodent donor cells. Here, we report the generation of an organoid culture system with striking biomimicry of the native immature testis tissue, including vasculature. Using piglet testis cells as starting material, we optimized conditions for the formation of cell spheroids, followed by long-term culture in an air-liquid interface system. Both fresh and frozen-thawed cells were fully capable of self-reassembly into stable testis organoids consisting of tubular and interstitial compartments, with all major cell types and structural details expected in normal testis tissue. Surprisingly, our organoids also developed vascular structures; a phenomenon that has not been reported in any other culture system. In addition, germ cells do not decline over time, and Leydig cells release testosterone, hence providing a robust, tunable system for diverse basic and applied applications.

Long-Term Monitoring of Donor Xenogeneic Testis Tissue Grafts and Cell Implants in Recipient Mice Using Ultrasound Biomicroscopy.

Testis tissue xenografting and testis cell aggregate implantation from various donor species into recipient mice are novel models for the study and manipulation of testis formation and function in target species. Thus far, the analysis of such studies has been limited to surgical or post-mortem retrieval of samples. Here we used ultrasound biomicroscopy (UBM) to monitor the development of neonatal porcine testis grafts and implants in host mice for 24 wk, and to correlate UBM and (immuno)histologic changes. This led to long-term visualization of gradual changes in volume, dimension and structure of grafts and implants; detection of a 4 wk developmental gap between grafts and implants; and revelation of differences in implant development depending on the craniocaudal site of implantation on the back of host mice. Our data support the reliability and precision of UBM for longitudinal study of transplants, which eliminates the need for frequent surgical sampling.

Live-cell imaging and ultrastructural analysis reveal remarkable features of cultured porcine gonocytes.

Gonocytes in the neonatal testis have male germline stem cell potential. The objective of the present study was to examine the behavior and ultrastructure of gonocytes in culture. Neonatal porcine testis cells were cultured for 4 weeks and underwent live-cell imaging to explore real-time interactions among cultured cells. This included imaging every 1 h from day 0 to day 3, every 2 h from day 4 to day 7, and every 1 h for 24 h at days 14, 21, and 28. Samples also underwent scanning electron microscopy, transmission electron microscopy, morphometric evaluations, immunofluorescence, and RT-PCR. Live-cell imaging revealed an active amoeboid-like movement of gonocytes, assisted by the formation of extensive cytoplasmic projections, which, using scanning electron microscopy, were categorized into spike-like filopodia, leaf-like lamellipodia, membrane ruffles, and cytoplasmic blebs. In the first week of culture, gonocytes formed loose attachments on top of a somatic cell monolayer and, in week 2, formed grape-like clusters, which, over time, grew in cell number. Starting at week 3 of culture, some of the gonocyte clusters transformed into large multinucleated embryoid body-like colonies (EBLCs) that expressed both gonocyte- and pluripotent-specific markers. The number and diameter of individual gonocytes, the number and density of organelles within gonocytes, as well as the number and diameter of the EBLCs increased over time (P < 0.05). In conclusion, cultured porcine gonocytes displayed extensive migratory behavior facilitated by their various cytoplasmic projections, propagated, and transformed into EBLCs that increased in size and complexity over time.

Validation of ultrasound biomicroscopy for the assessment of xenogeneic testis tissue grafts and cell implants in recipient mice.

BACKGROUND: Subcutaneous grafting/implantation of neonatal testis tissue/cells from diverse donor species into recipient mice can be used as an in vivo model to study testis development, spermatogenesis, and steroidogenesis. Ultrasound biomicroscopy (UBM) allows obtaining high definition cross-sectional images of tissues at microscopic resolutions. OBJECTIVES: The present study was designed to (a) validate the use of UBM for non-invasive monitoring of grafts/implants overtime and to (b) correlate UBM findings with the morphological attributes of recovered grafts/implants. MATERIALS AND METHODS: Testis tissue fragments (~14 mm3 , each) and cell aggregates (100 × 106 cells, each) obtained from 1-week-old donor piglets (n = 30) were grafted/implanted under the back skin of immunodeficient mice (n = 6) in eight analogous sites per mouse. Three-dimensional transcutaneous Doppler UBM was performed, and a randomly selected graft and its corresponding implant were recovered at 2, 4, 6, and 8 weeks. RESULTS: Graft/implant weight (P = .04) and physical height (P = .03) increased overtime. The dynamics of physical length and volume increases over time differed between tissue grafts and cell implants (P = .02 and 0.01 for sample type*time interactions, respectively). UBM-estimated volume was correlated with the post-recovery weight and volume of the grafts/implants (r = 0.98 and r = 0.99, respectively; P < .001). Pre- and post-recovery length and height of the grafts/implants were positively and strongly correlated (r = 0.50, P = .01; r = 0.70, P = .001) and so were the areas covered by cordal, non-cordal, or fluid-filled cavities between UBM and histology (r = 0.87, P < .001). DISCUSSION AND CONCLUSION: UBM findings correlated with physical attributes of the grafts/implants, validating its use as a non-invasive high-fidelity tool to quantify the developmental changes in ectopic testis tissue grafts and cell implants, potentially leading to a reduction in the number of recipient mice needed for similar experiments.

Effects of COX inhibitors on responsiveness of the tracheal tract to acetylcholine and histamine and their relationship with LTC4 and PGE2 levels of bronchoalveolar lavage fluid in allergic Guinea pigs.

Introduction: Nonsteroidal anti-inflammatory drugs (NSAIDs) intervene in the COX (cyclooxygenase) pathways which generate two important inflammation mediators, prostaglandins (PGs) and leukotriene (LTs). Contradictory claims regarding the effect of NSAIDs in asthmatic patients continues to be an issue. The present study investigated the effects of COX inhibitors on the responsiveness of the tracheal tract and on the levels of LTC4 and PGE2 in cells of the bronchoalveolar lavage fluid in an allergic guinea pig model.Materials and Methods: Adult male Dunkin-Hartley guinea pigs (250 - 300 g) were divided into seven groups of six animals each. Four COX inhibitors, aspirin (200 mg/kg and 20 mg/kg), indomethacin (10 mg/kg), ketoprofen (10 mg/kg), and celecoxib (25 mg/kg), were given orally on day 17 to allergy induced guinea pigs at 0, 12, and 24 h before ovalbumin challenge on day 18. PGF2 and LT4 were measured in the bronchoalveolar lavage fluid as well as inflammatory cell count and total protein. Tracheal responsiveness to acetylcholine (Ach) and histamine (His) also was evaluated.Results: An augment in the response of the trachea to Ach and His, as well as overt allergenic signs including short breath, wheezing and sneezing, was observed. The most significant increase in tracheal hyper-responsiveness was observed in the ketoprofen-treated group with similar but less pronounced changes observed in the indomethacin-treated group. Although some variables increased with the aspirin and celecoxib treatments, overall the tracheal sensitivity was reduced. Inflammatory cells including eosinophils and neutrophils corresponded to the changes observed for each treatment group.Conclusion: Ketoprofen and indomethacin increased the tracheal sensibility to Ach and His; therefore, their administration is not recommended in patients susceptible to allergy.

Age, period and cohort analysis of high cholesterol levels in Iranian adults over a 20-year period.

PURPOSE: Hypercholesterolemia is one of the most important modifiable risk factors of non-communicable diseases and data on their values in different societies and their trend of changes should be updated every couple of years. Many studies have focused on assessing the prevalence of high cholesterol. We must emphasise that most of these studies were cross-sectional and did not directly investigate the temporal trends of change for age, period and birth cohort (APC). The aim of this study is to evaluate the effect of age, period and birth cohort on the prevalence of borderline to high cholesterol levels in Iranian adult population. METHODS: The data were collected from 110,302 subjects between 25 and 69 years of age over the period of 1990-2011. Data from these subjects were collected by using five national cross-sectional surveys conducted in 1990-91, 1999, 2003, 2007 and 2011. The APC effect on the prevalence of borderline and high cholesterol levels was assessed using the Intrinsic Estimator model. RESULTS: The overall prevalence of borderline cholesterol level among male subjects was found to be lower than that of females (39.8% vs. 46.3%). Similarly, the prevalence of high cholesterol level in men was reported to be 13.1%, which was lower than the 18.0% calculated in women. The prevalence of borderline and high cholesterol levels increased with age in men between the ages of 45-49. Then it stayed quite steady and eventually declined. Then it stayed quite steady and eventually declined. The prevalence in women also increased with age, with its maximum rise after the ages of menopause and a slight decline at the ages of 65-69. As for the birth cohorts, the prevalence of borderline and high cholesterol levels followed a declining trend by going from earlier birth cohorts to the later ones. CONCLUSION: The present study provides evidence that age, period and birth cohort affect the prevalence of borderline and high cholesterol levels. Thus, these factors should be considered when developing and implementing care plans for people with hypercholesterolemia.

Blood Pressure Nomograms for Children and Adolescents by Age and Body Mass Index in Tehran, Iran.

BACKGROUND: Normal standard references of blood pressure (BP) for children and adolescents should be constructed according to anthropometric indices. Therefore, we aimed to produce BP reference percentiles by body mass index (BMI). METHODS: Data on demographic characteristics, anthropometric indices and BP values of 16246 3-18-year-old children and adolescents from 3 cross-sectional studies conducted in Tehran were included. To justify the need for BMI adjustment, quantile regression model was applied for different percentiles of systolic and diastolic BPs with age, sex, and the corresponding BMI percentiles. Then, Age- and sex-specific BP nomograms were constructed according to BMI. RESULTS: All regression coefficients for BMI percentiles were significant in quantile regression of BPs, confirming the necessity for BMI-adjusted nomograms of BP. The BP percentiles for each gender by age and BMI are presented. All the BP percentiles rose steadily in all BMI percentiles with minor discrepancies between the two genders. As observed, the prevalence of hypertension is estimated to be lower among the lean subjects and higher among overweighs when the BMI-adjusted BP curves are considered. CONCLUSION: The reference database constructed in this survey is the first Iranian BP reference by age and BMI in children and adolescents, from it concluded that BMI-adjusted BP curves depict a more precise picture of the hypertension prevalence and present a more reliable classification standard for hypertension.

The Most Important Causes of Death in Iranian Population; a Retrospective Cohort Study.

INTRODUCTION: Health care providers and health policy managers need updated and valid information regarding causes of death (COD) for development the health care facilities, directing primary prevention, assigning funds, and promoting public health. The major causes of death and its burden have not been yet appropriately identified in Iran. Although several studies had been carried out in this area, most of them were local or performed in the past years and need to be update. Thus, the present study aimed to address the major causes of death and its burden in Iran. METHODS: The present cross-sectional study was performed on graduate students and their families from February to March 2014. Through a two-stage random sampling procedure, data on 11315 subjects were obtained. The corresponding age of death, gender, and calendar year of death were inquired. All causes of death were categorized in nine groups including major cardiovascular disease, cancers, motor vehicle accidents, unintentional injuries, intentional injuries, stroke, lower respiratory infections, diabetes, and other reasons. Years of life lost (YLL) and person years of life lost were computed as the burden of diseases. RESULTS: Totally, 11315 (50.4% male) subjects were studied. The results regarding death of relatives revealed that 360 deaths occurred (66.9% male). COD in 95 cases (26.4%) was cardiovascular diseases, 64 (17.8%) motor vehicle accidents, 41 (11.4%) cancers, 23 (6.4%) unintentional injuries, 22 (6.1%) intentional injuries, 10 (2.8%) stroke, 8 (2.2%) lower respiratory infections, 6 (1.8%) diabetes, and 91 (25.3%) other reasons. The average YLL due to all COD was 34.4±18.5. YLL for motor vehicle accidents and injuries (unintentional and intentional) were higher than cardiovascular diseases (p<0.001). In addition, person years of life lost for motor vehicle accidents were 2613.1 years. Cardiovascular diseases (2159.4 years), cancers (1321.0 years), and unintentional injuries (990.4 years) were in the next ranks. CONCLUSION: Based on the findings, it seems that cardiovascular diseases, motor vehicle accidents, cancers, intentional and unintentional injuries are the major causes of death in Iranian population. Most of years of life lost were due to motor vehicle accidents, cardiovascular diseases and cancers, intentional and unintentional injuries, respectively.

Twenty-year dynamics of hypertension in Iranian adults: age, period, and cohort analysis.

Hypertension is a well-known health problem all over the world. Many studies have assessed its prevalence and associated risk factors, but all were cross-sectional and did not evaluate the trend of hypertension through all three different temporal dimensions including age, period, and cohort. So, we aimed to assess the 20-year dynamics of hypertension via the age-period-cohort model. Data from 74,155 subjects aged 25-60 years gathered through five national health surveys (1990-91, 1999, 2003, 2007, and 2011) were used in this study. The age-period-cohort effect on hypertension was analyzed using the intrinsic estimator model. The prevalence of hypertension increased with age for both genders except for males in 2003 and 2011 periods with drops of 3.5% for ages 55-60 and 8.1% for ages 50-60, respectively. As for the period effect, the prevalence of hypertension was almost constant in all age groups for both genders from 1990-1999. The cohort-based prevalence of hypertension showed a declining trend in all cohorts for females except for 2011 in birth cohort of 1950-1955 which remains stationary. The trend of prevalence for males also follows a decreasing trend except for periods of 2003, 2007, and 2011; birth cohorts of 1945-1949, 1975-1980, and 1950-1960 increase by 3.5%, 1.9%, and 8.1%, respectively. The age effect on the prevalence of hypertension showed an almost monotonic increasing trend. The period effect increased the total prevalence of hypertension from 1992 to 1997. The cohort effect also showed a monotonic decrease in hypertension prevalence except for a few discrepancies.

Blood pressure percentiles by age and body mass index for adults.

Since no comprehensive study has been conducted on blood pressure (BP) percentiles established upon nationally representative sample population of adults, the present study aimed to construct the blood pressure percentiles by age, sex and body mass index (BMI) of the subjects. Analyses were based on data collected in 2011 from 8,425 adults aged 25 to 69 years old. Data on demographic characteristics, anthropometric measurements, and blood pressure was recorded for each subject. Linear Regression analysis was used to assess the adjusted relationship of age-sex-specific standard deviation scores of BMI, height, and weight with blood pressure. Four separate models for systolic blood pressure (SBP) and diastolic blood pressure (DBP) of men and women were constructed for BP percentiles according to age and BMI. Blood pressure increased with the rise in BMI and weight, but showed a negative correlation with height. SBP and DBP rose steadily with increasing age, but the rise in SBP was greater than DBP. Overweight and obese population, seem to fall into the category of hypertensive. The findings of present study show that BP percentiles are steadily increased by age and BMI. In addition, most obese or overweight adults are hypertensive.