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This study was undertaken to determine whether there was an association between fine particles (PM₂.₅) levels and hospital admissions for congestive heart failure (CHF) in Taipei, Taiwan. Hospital admissions for CHF and ambient air pollution data for Taipei were obtained for the period 2006-2010. The relative risk of hospital admissions was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality and long-term time trends. For the single pollutant model (without adjustment for other pollutants), increased CHF admissions were significantly associated with PM₂.₅ both on warm days (23 °C) and cool days (23 °C), with an interquartile range increase associated with a 13% (95% CI = 9-17%) and 3% (95% CI = 0-7%) increase in CHF admissions, respectively. In the two-pollutant models, PM₂.₅ remained significant after the inclusion of SO₂ or O₃ both on warm and cool days. This study provides evidence that higher levels of PM₂.₅ increase the risk of hospital admissions for CHF.

This study was undertaken to determine whether there was a correlation between air pollutant levels and hospital admissions for myocardial infarction (MI) in Taipei, Taiwan. Hospital admissions for MI and ambient air pollution data for Taipei were obtained for the period 1996-2006. The relative risk of hospital admissions was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-pollutant models, on warm days (>23 degrees C) statistically significant positive associations were found for all pollutants except sulfur dioxide (SO(2)). On cool days (

For better understanding of phylogenetic diversity and evolution of pituitary thyroid-stimulating hormone (TSH) in birds, we have cloned the cDNAs encoding TSH beta subunit (TSHbeta), by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) from two species of domestic ducks, common duck (Tsaiya duck and Pekin duck) (Anas platyrhynchos domesticus) and mule duck (hybrid of male muscovy duck Cairina moschata and female A. platyrhynchos domesticus). The nucleotide sequences of isolated TSHbeta cDNAs of the two species of ducks are identical, with each including 66 bp of 5'-untranslated region (UTR), 402 bp of coding region, and 82 bp 3'-UTR followed by 18 bp poly A tract. The deduced TSHbeta subunit of the ducks contains 134 amino acids consisting of a putative signal peptide of 19 amino acids and a putative mature protein of 115 amino acids. However, the TSHbetas of common duck and mule duck differ from the TSHbeta of muscovy duck in one amino acid at position 97 of the mature protein: isoleucine for common duck and mule duck, and valine for muscovy duck. Our findings thus demonstrate that inter-genus variation of TSHbeta exists in Family Anatidae, and that TSHbeta gene in the mule duck is preferentially transcribed from the maternal genome rather than from the paternal genome. TSHbeta mRNA expressions were investigated by culturing common duck pituitaries with various doses of hormones. Thyrotropin-releasing hormone (TRH) stimulated, while thyroid hormones, triiodothyronine (T(3)) and thyroxine (T(4)), inhibited the TSHbeta mRNA levels, in dose-related manners. The findings thus support that the mode of regulation of TSH gene expression in hypothalamo-pituitary-thyroid axis in birds is similar to that in mammals. Cortisol and corticosterone decreased the steady-state TSHbeta mRNA levels at the pituitary level, in a dose-related manner, the first-time demonstration in vertebrates. The results may suggest that glucocorticoids exert suppressive action directly at pituitary level in modulation of steady-state TSHbeta mRNA level.

To investigate the effect of perinatal testosterone exposure, which simulates the endogenous testosterone peak, on neuron loss during aging, nuclear morphology was evaluated in male and female rats as well as in female rats treated with testosterone perinatally followed by ovariectomy (TE/Ovx). Additionally, neuronal apoptosis, which occurred primarily at postnatal day 8 (PND8), was identified by in situ TUNEL staining. Neuronal density, nuclear volume, total neuronal number and pyknotic ratio were estimated after HE stain at PND8, middle age and old age. The results showed that age-related decrease in neuronal nuclear volume and total neuron number in the sexually dimorphic nucleus of the preoptic area (SDN-POA) of female rats was significantly diminished by TE/Ovx. The pyknotic ratio in the SDN-POA of female rats at PND8 was significantly higher than that of males, and neuronal death was reversed by testosterone exposure, while no significant difference of pyknotic ratios was observed among male, female and TE/Ovx female rats at both middle and old age. Moreover, the high apoptotic incidence of female rats at PND8 was significantly diminished by testosterone exposure. These results suggest that neuron loss in the SDN-POA during aging may be predominantly determined by perinatal testosterone through modulation of postnatal neuronal apoptosis.

Sexual dimorphism has been found in the preoptic area of the hypothalamus (POA), a major site of glutamate actions via N-methyl-D-aspartate (NMDA) receptors. The sexually dimorphic nucleus of the preoptic area (SDN-POA) of male rats exhibits about seven-fold greater nuclear volume than that of females. A naturally occurring neonatal neuronal apoptosis, that can be prevented by testosterone, may contribute to this sexual difference in SDN-POA nuclear volume. Since activation of NMDA receptors in the POA induces GnRH secretion, it may be involved in both elevation of serum testosterone and prevention of neuronal death in the SDN-POA. In the present study, protein expression of NMDA receptors in the POA of male and female fetuses was quantified on the day preceding the fetal testosterone peak (embryonic day 16; ED 16). Rats were then distributed in four groups: (1) untreated males, (2) untreated females, (3) males pretreated with MK-801 (a noncompetitive NMDA receptor antagonist), and (4) females pretreated with MK-801. Serum levels of testosterone were estimated on the afternoon of ED 18. Expression of Bcl-2 and Bax, as well as neuronal apoptosis in SDN-POA, were observed on postnatal day 8. The results showed that (1) expression of NMDA receptors in the POA of male fetuses was higher than that of females on ED 16; (2) levels of testosterone were lower in MK-801 pretreated male fetuses than in intact males on ED 18; (3) expression of Bcl-2 in the POA of MK-801 pretreated male rats was significantly less than that of control males; (4) the apoptotic incidence in the SDN-POA of MK-801 pretreated male rats was significantly greater than in control males, while there was no significant difference in apoptotic incidence in the SDN-POA between MK-801 pretreated and intact females. These results suggest that the NMDA receptor is highly expressed in prenatal male fetuses, and that it might play an important role in the elevation of testosterone levels. Moreover, activation of NMDA receptors may protect SDN-POA neurons from naturally occurring neuronal death, by modulating testosterone and/or Bcl-2 expression.

The possible association between the risk of gastric cancer and the levels of calcium, magnesium, and nitrate in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. Records of gastric cancer deaths among eligible residents in Taiwan from 1987 through 1991 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair-matched to the cases by sex, year-of-birth, and year-of-death. Each matched control was selected randomly from the set of possible controls for each case. Data on calcium, magnesium, and nitrate levels in drinking water throughout Taiwan were obtained from the Taiwan Water Supply Corporation. The municipality of residence of the cases and controls was assumed to be the source of the subject's calcium, magnesium, and nitrate exposure via drinking water. The subjects were divided into tertiles according to the levels of calcium, magnesium, and nitrate in their drinking water. The results of the present study show that there is a significant positive association between drinking water nitrate exposure and gastric cancer mortality. The present study also suggests that there was a significant protective effect of calcium intake from drinking water on the risk of gastric cancer. Magnesium also exerts a protective effect against gastric cancer, but only for the group with the highest levels.

Neuronal nuclear volumes (NNVs) were measured in the medial preoptic nucleus (MPN), anterior hypothalamic area (AHA) and arcuate nucleus (ARN) of young adult, middle-aged, and old rats of both sexes. The NNVs in the darkly stained sexual-dimorphic nucleus of the preoptic area (SDN-POA) and the lighter staining surrounding area (non-SDN-POA) within the MPN were measured separately. Intact young and middle-aged female rats had larger NNVs than those of the males in SDN-POA, non-SDN-POA and AHA but not in ARN. During aging, only intact old female rats manifested significant NNV shrinkage in all the measured areas. Long-term treatment with estradiol benzoate (EB) caused a significant enlargement of the NNVs in non-SDN-POA and ARN of middle-aged and old male rats as well as the NNVs in SDN-POA, non-SDN-POA and ARN of old female rats. The enlarging effect of EB on NNVs in both SDN-POA and non-SDN-POA of female rats could be prevented by ovariectomy. Furthermore, NNVs in SDN-POA and non-SDN-POA of ovariectomized female rats were even smaller than those of the age-matched intact female rats. These results indicate that: (1) the NNVs of MPN and ARN in male and female rats were enlarged after long-term exposure of physiological dose of estradiol; (2) the enlarging effects of EB on NNV in MPN can explain why the NNV of intact female rats is larger than that of males, and (3) during aging, the sex-specific shrinkage of NNVs in MPN, AHA and ARN of female rats may be due to an intrinsic aging process rather than long-term effects of EB.

Many investigators have examined urbanization gradients in cancer rates. The purpose of this report was to identify urban-rural trends in cancer mortality rates (1982-1991) for municipalities in Taiwan. For this purpose, Taiwan's municipalities were classified as rural, suburban, urban, or metropolitan, using population density as an ordinal indicator of the degree of urbanization. Average annual age-adjusted, site-specific cancer mortality rates were calculated for both sexes within each population density group. Significant increasing trends with more urbanization were observed in mortality rates for cancers of the lung, pancreas, and kidney among both males and females, as well as male prostate cancer, and female breast and ovary cancer. In addition, this study revealed a significant rural excess for nonmelanoma skin cancer among both males and females, as well as male non-Hodgkin's lymphoma, and cancers of the female bone, and female connective tissue. Analytic studies for sites with consistent urban-rural trends may be fruitful in identifying the aspect of population density, or other unmeasured factors, that contribute to these trends.Almost all studies which have reported variation in cancer incidence and mortality rates across urbanization gradients have found higher rates in urban populations than in rural areas. Findings are presented from a study conducted to identify urban-rural trends in cancer mortality rates during 1982-91 for municipalities in Taiwan. The countries municipalities were classified as rural, suburban, urban, or metropolitan, using population density as an ordinal indicator of the degree of urbanization. Average annual age-adjusted, site-specific cancer mortality rates were calculated for both sexes within each population density group. Significant increasing trends with more urbanization were observed in mortality rates for cancers of the lung, pancreas, and kidney among both men and women, as well as male prostate cancer and female breast and ovary cancer. The study also found a significant rural excess for non-melanoma skin cancer among men and women, as well as male non-Hodgkin's lymphoma and cancers of the female bone and connective tissue.

The neurotoxic effect of monosodium L-glutamate (MSG) on the morphologies in the darkly stained sexually dimorphic nucleus of the preoptic area (SDN-POA) and the lighter-staining surrounding area (non-SDN-POA) within the medial preoptic nucleus (MPN) was evaluated. Male and female Long-Evans rats were used. MSG (4 mg/g of body weight) was administered subcutaneously to pups on days 1 and 3 postnatally. Normal saline was used as the vehicle. At the age of 6 months, the rats were sacrificed and the brain tissues were fixed for histological examination. The morphological changes, i.e., total volume, density, total neuron number, neuronal nuclear volume (NNV) and ratio of pyknosis, of the SDN-POA and non-SDN-POA within the MPN, were estimated using the AMS VIDS III semiautomatic image-analytic system. The results indicate that neonatal MSG treatment caused significant neuronal loss and decreases in total volume of the SDN-POA and non-SDN-POA of male and female rats. However, only the SDN-POA of MSG-treated male rats showed a significant increase of pyknosis and decrease of neuronal density. A significant enlargement of NNV in the SDN-POA and non-SDN-POA was observed in the MSG-treated male rats. These results indicate that the MPN shows sex-specific and area-specific changes after neonatal neurotoxicity due to MSG.

The age-related morphological changes in the darkly stained sex-dimorphic nucleus (SDN-POA) and the lighter staining surrounding area (non-SDN-POA) within the medial division of preoptic nucleus of Long-Evans rats were studied. The long-term effects of estradiol benzoate (EB) on the changes were also assessed. During aging, the neuron loss in 14-(middle-age) and 22-month-old rats as well as increased pyknotic ratio of neurons in old male rats were observed in SDN-POA, but not in the non-SDN-POA. In female rats, significant neuron loss with advancing age was observed both in SDN-POA and the non-SDN-POA. Neuron loss in SDN-POA of EB-treated males was more severe than that of the intact males, while no significant difference of neuron loss was observed between EB-treated and age-matched intact female rats. However, neuron loss in SDN-POA of ovariectomized female rats was more severe than that of the age-matched intact females. These results indicate that age-related neuron loss in medial preoptic nucleus show sex-specific and area-specific features, and estradiol may play a important role in modulating neuron loss during aging.

The crude major lower limb amputation procedure rate is 8.8 per 100,000 of the population per year in Taiwan. From January 2002 to October 2006, patients that received major lower limb amputation in our department were enrolled in this study. Retrospective chart reviews concerning different factors that can affect the eventual postoperative functional status were investigated. Factors that affected the length of hospital stay included duration before amputation (P < 0.001) and renal function (P = 0.045). Phantom limb pain was affected by wound healing time (P = 0.006). Factors that affected the daily prosthesis usage time were initial infection status (P = 0.021), renal function (P = 0.01), patient educational level (P = 0.016), and pretraining waiting time (P = 0.003). The duration of prosthetic training was affected by patient educational level (P = 0.004) and marital status (P = 0.024). In addition, subjective satisfaction about the usage of prosthesis was affected by pretraining waiting time (P = 0.001) and daily prosthesis usage time (P < 0.001). The daily prosthesis usage time was closely related to life quality improvement (P < 0.001) and subjective satisfaction of prosthesis usage (P < 0.001). Despite reported unchangeable factors like age, end-stage renal disease, dementia, coronary artery disease, and level of amputation, preprosthesis training waiting time significantly affected the satisfaction and daily usage time of the prosthesis. Surgeons can make some contribution to accelerate amputation wound healing and stump maturation by choosing the correct operating procedure, delicately managing the soft tissue, and ascertaining proper wound care to improve the outcome.

The role of N-methyl-d-aspartate (NMDA) receptor in mediating the effect of testosterone exposure prenatally on neuronal apoptosis in the sexual dimorphic nucleus of the preoptic area (SDN-POA) of rats was studied. The endogenous testosterone was diminished by prenatal stress (PNS) or simulated by testosterone exposure (TE) to understand the effect of testosterone on NR1(a functional subunit protein of NMDA receptor) expression and neuronal apoptosis. To further study whether the testosterone, after being converted into estradiol, modulates NR1expression, 4-androstein-4-ol-3,17-dione (ATD; an aromatase inhibitor) was used to block the conversion of estradiol from testosterone. The expressions of the NR1mRNA and NR1subunit protein were quantified by RT-PCR and western blotting analysis, respectively. In addition, a noncompetitive antagonist of NMDA receptor, MK-801, was used to find out whether blockage of NMDA receptor affects the naturally occurring apoptosis in SDN-POA. The results showed the following. 1) Expression of perinatal NR1subunit protein in the central part of the medial preoptic area of male rats was significantly higher than that of females, especially on postnatal days 1 and 3. 2) The testosterone level of male fetuses on embryonic day 18 was significantly higher than that of females, while the testosterone level of TE females or PNS males was similar to that of intact males or intact females, respectively. 3) The apoptotic incidence of intact male rats was significantly less than that of females, and the apoptosis was stimulated by PNS in male or inhibited by TE in female. 4) The expression of NR1subunit protein could be inhibited by PNS or ATD-treatment in male, while stimulated by TE in female. 5) NR1mRNA showed no significant difference among intact male, PNS male, ATD-treated male, TE female and intact female rats. 6) The low apoptotic incidence of male rats was significantly increased when NMDA receptor was blocked by MK-801. These results suggest that testosterone, after being converted to estradiol, may prevent the SDN-POA neurons of male rats from apoptosis through enhancing the expression of NR1at the posttranscriptional level.

The objective of this study was to examine the relationship between indoor environmental factors and atopic eczema in a subtropical area. A case-control study was performed using participants from a survey that included 144 school children with atopic eczema and 144 age- and gender-matched controls. The study was confined to 4,164 primary school children aged 6-12 yr attending 8 primary schools in Kaohsiung rural municipalities who participated in the study. Cases of atopic eczema were ascertained by asking whether a physician had ever diagnosed this condition in the child. Information regarding the home environment was obtained using a structured written questionnaire, completed by the parents of the children. Of the many indoor environmental factors included in this study, such as dampness and smoking, none was found to be associated with atopic eczema.