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Background: An increased risk for ischaemic stroke has been reported in young hyperthyroidism patients independent of atrial fibrillation (AF). However, whether the use of antithyroid drugs in hyperthyroidism patients can reduce the occurrence of ischaemic stroke remains unclear., Methods: A total of 36,510 newly diagnosed hyperthyroidism patients during 2003-2006 were identified from the Taiwan National Health Insurance Research database. Each patient was individually tracked for 5 years from their index date (beginning the antithyroid drugs) to identify those who suffered from new episode of ischaemic stroke. Medication possession ratio (MPR) was used to represent the antithyroid drug compliance. The association between the MPR and the risk of stroke was examined., Results: The stroke incidence rates for hyperthyroidism patients with age < 45 years and age ≥ 45 years were 0.42 and 3.76 per 1000 person-years, respectively. The patients aged < 45 years with MPR < 0.2 (adjusted hazard ratio, HR, 2.30; 95% CI, 1.13-4.70; p = 0.02) and 0.2 ≤ MPR < 0.4 (adjusted HR, 2.24; 95% CI, 1.06-4.72; p = 0.035) had a significantly increased risk of ischaemic stroke as compared to those with ≥ 0.6. In patients of the age ≥ 45 years, only the patients with MPR < 0.2 (adjusted HR, 1.44; 95% CI, 1.03-2.01; p = 0.036) had a significantly higher risk of ischaemic stroke as compared to those with MPR ≥ 0.6. In hyperthyroidism patients without AF, good antithyroid drugs compliance also reduced the incidence of stroke significantly (adjusted HR, range: 1.52-1.61; p = 0.02); but not in hyperthyroidism with AF., Conclusion: Hyperthyroidism patients with good antithyroid drug compliance had a lower risk of ischaemic stroke than patients with poor compliance., (© 2015 John Wiley & Sons Ltd.)

Drinking water shortage has become worse in recent decades. A new capacitive deionization (CDI) method for increasing water supplies through the effective desalination of seawater has been developed. Silver as nano Ag and Ag@C which was prepared by carbonization of the Ag(+)-β-cyclodextrin complex at 573 K for 30 min can add the antimicrobial function into the CDI process. The Ag@C and Ag nanoparticles dispersed on reduced graphene oxide (Ag@C/rGO and nano Ag/rGO) were used as the CDI electrodes. The nano Ag/rGO and Ag@C/rGO electrodes can reduce the charging resistant, and enhance the electrosorption capability. Better CDI efficiencies with the nano Ag/rGO and Ag@C/rGO electrodes can therefore be obtained. When reversed the voltage, the electrodes can be recovered up to 90% within 5 min. This work presents the feasibility for the nano Ag and Ag@C on rGO electrodes applied in CDI process to produce drinking water from seawater or saline water., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Experiments with electron or ion matter waves require a coherent, monochromatic and long-term stable source with high brightness. These requirements are best fulfilled by single atom tip (SAT) field emitters. The performance of an iridium covered W(111) SAT is demonstrated and analyzed for electrons in a biprism interferometer. Furthermore we characterize the emission of the SAT in a separate field electron and field ion microscope and compare it with other emitter types. A new method is presented to fabricate the electrostatic charged biprism wire that separates and combines the matter wave. In contrast to other biprism interferometers the source and the biprism size are well defined within a few nanometers. The setup has direct applications in ion interferometry and Aharonov-Bohm physics., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In contemporary reinforcement learning models, reward prediction error (RPE), the difference between the expected and actual reward, is thought to guide action value learning through the firing activity of dopaminergic neurons. Given the importance of dopamine in reward learning and the involvement of Akt1 in dopamine-dependent behaviors, the aim of this study was to investigate whether Akt1 deficiency modulates reward learning and the magnitude of RPE using Akt1 mutant mice as a model. In comparison to wild-type littermate controls, the expression of Akt1 proteins in mouse brains occurred in a gene-dosage-dependent manner and Akt1 heterozygous (HET) mice exhibited impaired striatal Akt1 activity under methamphetamine challenge. No genotypic difference was found in the basal levels of dopamine and its metabolites. In a series of reward-related learning tasks, HET mice displayed a relatively efficient method of updating reward information from the environment during the acquisition phase of the two natural reward tasks and in the reverse section of the dynamic foraging T-maze but not in methamphetamine-induced or aversive-related reward learning. The implementation of a standard reinforcement learning model and the Bayesian hierarchical parameter estimation show that HET mice have higher RPE magnitudes and that their action values are updated more rapidly among all three test sections in T-maze. These results indicate that Akt1 deficiency modulates natural reward learning and RPE. This study showed a promising avenue for investigating RPE in mutant mice and provided evidence for the potential link from genetic deficiency, to neurobiological abnormalities, to impairment in higher-order cognitive functioning., (© 2012 The Authors. Genes, Brain and Behavior © 2012 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.)

The aim of this study was to evaluate the production of chicken anaemia virus VP3 protein in different Escherichia coli strains and to address the diagnostic application of purified E. coli-expressed VP3 protein for the detection of chicken anaemia virus (CAV) infection and the development of an ELISA kit. Three E. coli strains, BL21, BL21 codonplus RP and BL21 pLysS, each harbouring a VP3 protein expressing plasmid, were investigated after induction to produce recombinant VP3 protein. After isopropyl-β-D-thiogalactoside (IPTG) induction, VP3 protein was successfully expressed in all three E. coli strains. The BL21 pLysS strain gave the best performance in terms of protein productivity and growth profile. In addition, the optimal culture temperature and IPTG concentration were found to be 0.25 mM and 20 °C, respectively. Using Ni-NTA-purified VP3 protein as an ELISA coating antigen, the purified VP3 was shown to be highly antigenic and able to discriminate sera from chickens infected with CAV from those that were uninfected during an evaluation of CAV infection serodiagnosis. A VP3-based ELISA demonstrated 100% (6/6 x 100%) specificity and sensitivities of 91.3% (21/23 x 100%) and 82.6% (19/23 x 100%) using cut-off values of the mean plus 2 SD and the mean plus 3 SD, respectively., (© 2011 Blackwell Verlag GmbH.)

Prediction model for hypertension risk in Chinese is still lacking. We aimed to propose prediction models for new-onset hypertension for ethnic Chinese based on a prospective cohort design on community, which recruited 2506 individuals (50.8% women) who were not hypertensive at the baseline (1990-91). Total 1029 cases of new-onset hypertension developed during a median of 6.15 (interquartile range, 4.04-9.02) years of follow-up. In the clinical model, gender (2 points), age (8 points), body mass index (10 points), systolic blood pressure (19 points) and diastolic blood pressure (7 points) were assigned. The biochemical measures, including white blood count (3 points), fasting glucose (1 point), uric acid (3 points), additional to above clinical variables, were constructed. The areas under the receiver operative characteristic curves (AUCs) were 0.732 (95% confidence interval (CI), 0.712-0.752) for the point-based clinical model and 0.735 (95% CI, 0.715-0.755) for the point-based biochemical model. The coefficient-based models had a good performance (AUC, 0.737-0.741). The point-based clinical model had a similar net reclassification improvement as the coefficient-based clinical model (P=0.30), and had a higher improvement than the point-based biochemical model (P=0.015). We concluded that the point-based clinical model could be considered as the first step to identify high-risk populations for hypertension among Chinese.

Oncofetal genes are expressed in embryos or fetuses, are downregulated or undetectable in adult tissues, and then re-expressed in tumors. Known oncofetal genes, such as AFP, GCB, FGF18, IMP-1 and SOX1, often have important clinical applications or pivotal biological functions. To find new oncofetal-like genes, we used the public information of expressed sequence tags to systematically analyze gene expression patterns and identified a novel oncofetal-like gene, LRRC16B. It increased the proliferation, anchorage-independent growth and tumorigenesis of transformed cells in xenografts, possibly through its effects on cyclin B1 protein levels. These findings exemplify the feasibility of using bioinformatics to find new oncofetal-like genes and suggest that more genes with important functional roles will be uncovered in the candidate gene list.

Aim: Chicken anaemia virus (CAV) causes an economically important viral disease in chickens worldwide. The main aim of this study was to establish a rapid, sensitive and specific loop-mediated isothermal amplification (LAMP) assay for detecting CAV infection., Methods and Results: A set of four specific LAMP primers were designed based on the nucleotide sequence of the CAV VP2 gene, which encodes a nonstructural protein. These were used for the amplification of a specific target region of the VP2 gene. LAMP amplicons were successfully amplified and detected by DNA electrophoresis and by direct naked eye SYBR Green I visualization. A sensitivity test systematically demonstrated that the LAMP assay was superior to a conventional PCR assay with a minimum concentration limit of 100 fg compared to 10 ng for the conventional PCR. The specificity of the LAMP assay for CAV detection is consistent with conventional PCR. Using this established LAMP assay, infected and uninfected clinical samples obtained from an experimental farm were fully verified., Conclusions: A novel nucleic acid-based approach of LAMP assay was successfully developed for detecting CAV infection., Significance and Impact of the Study: In this study, these results indicate that the developed LAMP assay herein for CAV detection is a time-effective, simple, sensitive and specific test that can be used as an alternative approach in the future for large-scaled diagnosis on the farm of CAV infection.

Coexpression of multiple shRNAs can simultaneously inhibit multiple genes or target multiple sites on a single gene. These approaches can be used for dissecting complex signaling pathways and even be applied to targeting multiple genes in cancer therapy. Here we established a simple and efficient multiple shRNAs expression system based on pSUPER, the most popular expression vector in mammalian cells. A series of head-to-tail tandem array multiple shRNAs expression vectors were constructed containing different combinations of six shRNA expression cassettes targeting genes involved in cell proliferation and survival pathways: Bcl-2, Survivin, Akt1, Erk2, CyclinE and NFkappaB. In HeLa and HEK293 cells, the multiple shRNAs expression constructs could efficiently and simultaneously induce inhibition of all six genes. We further evaluated the inhibition effects of the multiple shRNAs expression vectors on the human prostate cancer cell line PC3, which contains different cell variants with distinct oncogenic signaling alterations. The results revealed that the multiple shRNAs expression system could inhibit all six genes and was much more efficient in inducing apoptosis in the PC3 cells. Our results suggest that the multitarget shRNAs expression system could be an effective strategy in cancer therapy and be applied to any other DNA vector-based shRNA expression system.

Background: Angiostatin, a circulating angiogenic inhibitor, is an internal fragment of plasminogen and consists of several isoforms, K1-3 included. We previously showed that K1-3 was the most potent angiostatin to induce E-selectin mRNA expression. The purpose of this study was to identify the mechanism responsible for K1-3-induced E-selectin expression and investigate the role of E-selectin in the anti-angiogenic action of K1-3., Methods and Results: Quantitative real time RT-PCR and Western blotting analyses confirmed a time-dependent increase of E-selectin mRNA and protein induced by K1-3. Subcellular fractionation and immunofluorescence microscopy showed the co-localization of K1-3-induced E-selectin with caveolin 1 (Cav1) in lipid rafts in which E-selectin may behave as a signaling receptor. Promoter-driven reporter assays and site-directed mutagenesis showed that K1-3 induced E-selectin expression via promoter activation and AP1 and Ets-1 binding sites in the proximal E-selectin promoter were required for E-selectin induction. The in vivo binding of both protein complexes to the proximal promoter was confirmed by chromatin immunoprecipitation (ChIP). Although K1-3 induced the activation of ERK1/2 and JNK, only repression of JNK activation attenuated the induction of E-selectin by K1-3. A modulatory role of E-selectin in the anti-angiogenic action of K1-3 was manifested by both overexpression and knockdown of E-selectin followed by cell proliferation assay., Conclusions: We show that K1-3 induced E-selectin expression via AP1 and Ets-1 binding to the proximal E-selectin promoter (-356/+1), which was positively mediated by JNK activation. Our findings also demonstrate E-selectin as a novel target for the anti-angiogenic therapy.

Photodynamic therapy (PDT) is an effective therapy for local malignant tumors. Lonicera japonica was found to have the anti-tumor effect. The aim of this study is to explore the mechanisms of apoptosis induced by PDT in lung CH27 carcinoma cells with alcohol extract from Lonicera japonica as photosensitizer. Our study indicated that Lonicera japonica extracts exhibited significant photocytotoxicity in CH27 cells at a concentration range of 50-150 microg/ml, with 0.4-1.2J/cm2 light dose. PDT with Lonicera japonica extracts-induced cell death is a typical apoptosis that was accompanied by DNA condensation, externalization of phosphatidylserine and formation of apoptotic bodies. PDT with Lonicera japonica extracts was shown to be caspase-3-independent apoptosis via activation of AIF in this study. P38-associated pathway may be involved in apoptosis induced by PDT with Lonicera japonica extracts in CH27 cells. We also have demonstrated that PDT with Lonicera japonica extracts-induced CH27 cells apoptosis was probably related to its ability to change the protein expression and distribution of heat shock protein 27.

The role of the p38 mitogen-activated protein kinase (MAPK) pathway in hepatitis B virus (HBV) replication was investigated in this study. After transient transfection with HBV plasmid, p38 MAPK, but not JNK or ERK1/2, was significantly phosphorylated in human hepatoma cell Huh7. Interestingly, HBV proteins and RNA synthesis were significantly inhibited by a specific inhibitor of p38 MAPK, SB203580, in a dose-dependent manner. Intracellular core-associated DNA, extracellular virion-associated DNA and covalently closed circular DNA were also significantly inhibited by SB203580. Further results showed the antiviral role of nitric oxide (NO) on the suppression of HBV replication and downregulation of p38 MAPK phosphorylation. In conclusion, these results suggested that suppression of phosphorylation of p38 MAPK by inhibitor or NO could inhibit intracellular HBV replication.

Objective: Human uncoupling proteins 2 and 3 (UCP2 and UCP3) are two mitochondrial proteins that are involved in the control of metabolism of fatty acid and possibly protect against oxidative damage. The aim of this study was to analyze genetic associations of four polymorphisms of the UCP2 and UCP3 genes with insulin, leptin concentration and obesity in Taiwan aborigines., Research Methods: Four polymorphisms were compared in 324 obese (body mass index (BMI) > or =30 kg/m(2)) and overweight (30>BMI > or =25 kg/m(2)) subjects, and 114 normal weight subjects (BMI <25 kg/m(2)) in an aboriginal community of southern Taiwan. Anthropometric characteristics and fasting levels of insulin, leptin, triglycerides and cholesterol were measured., Results: Before and after adjusting for age distribution, only the Val55 allele in exon 4 of the UCP2 gene increased the risk of overweight and obesity (adjusted odds ratio (OR)=2.02, P=0.004) in comparison with Ala55. UCP2 V55V is also associated with higher fasting insulin levels than A55V (P=0.01) and A55A (P=0.04) in the obese/overweight group. Using the COCAPHASE program of the UNPHASED software, haplotype analysis of three single nucleotide polymorphisms (A55V-G866A-C-55T) revealed that A-G-C (73% in obese subjects and 77% in controls) was the most common haplotype and that the haplotype V-A-T (13% in obese subjects and 5% in controls) was significantly increased in obese and overweight subjects (BMI > or =25 kg/m(2)) (OR=2.62, P<0.001)., Discussions: UCP2 A55V variant might predispose to obesity and Val55 allele to confer population-attributable risk for 9.5% of obese disorders and increase insulin concentrations. The V-A-T haplotype within UCP2-UCP3 gene cluster is also significantly associated with obesity in Paiwan aborigines.

Background: Acute heart failure leads to high mortality and morbidity rates. The symptom of acute dyspnoea is non-specific and the diagnostic tools of acute heart failure are still not satisfactory. Tissue Doppler echocardiography is accurate in evaluating cardiac function; however, its efficacy in diagnosing patients with acute dyspnoea in emergency departments remains unclear., Methods: Patients with acute dyspnoea were included prospectively while visiting the emergency department. Tissue Doppler echocardiography was carried out and the ratios of peak early diastolic transmitral blood flow velocity (E) to the peak early diastolic tissue velocity over mitral annulus (Ea) were recorded. The sensitivity, specificity and accuracy of tissue Doppler parameters and the receiver-operating characteristic curves for diagnosing acute heart failure were also evaluated., Results: A total of 92 patients were enrolled. The ratio E:Ea was found to be a good diagnostic test to estimate the diagnostic performances of tissue Doppler echocardiography using receiver-operating characteristic curves in cases of acute heart failure in patients with preserved left ventricular systolic function (mean (SD) area under the curve = 0.875 (0.049); p<0.001; cut-off value = 11) and with left ventricular systolic dysfunction (mean (SD) area under the curve = 0.903 (0.061); p = 0.003; cut-off value = 16). E:Ea was an independent predictor of acute heart failure in multiple logistic regressions. For patients with a B-type natriuretic peptide level between 100 and 500 pg/ml, E:Ea provided an accuracy of 90.9% (p = 0.015) for diagnosing acute heart failure., Conclusions: Tissue Doppler echocardiography is accurate in diagnosing patients with acute heart failure in emergency departments. It can be a useful supplementary diagnostic tool for patients with inconclusive blood B-type natriuretic peptide level.

Aims: To determine the association between rainfall rate and occurrence of enterovirus infection related to contamination of drinking water., Methods and Results: One fatality case and three cases of severe illness were observed during the enterovirus epidemic in a village in southern Taiwan from 16 September to 3 October 1998. Groundwater samples were collected from the public well in the village after heavy rainfall to test for enterovirus using the reverse transcription-polymerase chain reaction (RT-PCR) assay. The RT-PCR assay detected the enterovirus in the groundwater sample collected on 26 September 1998. The logistic regression model also revealed a statistically significant association between the rainfall rate and the observation of cases of enterovirus infection., Conclusions: According to the fitted logistic regression model, the probability of detecting cases of enterovirus infection was greater than 50% at rainfall rates >31 mm h(-1). The higher the rainfall rate, the higher the probability of enterovirus epidemic., Significance and Impact of the Study: Contamination of drinking water by the enterovirus may lead to epidemics that cause deaths and severe illness, and such contamination may be caused by heavy rainfall. The major finding in this study is that the enterovirus could be flushed to groundwater in an unconfined aquifer after a heavy rainfall. This work allows for a warning level so that an action can be taken to minimize future outbreaks and so protect public health.

Grape seed proanthocyanidin extract (GPSE) at high doses has been shown to exhibit cytotoxicity that is associated with increased apoptotic cell death. Nitric oxide (NO), being a regulator of apoptosis, can be increased in production by the administration of GSPE. In a chick cardiomyocyte study, we demonstrated that high-dose (500 microg/ml) GSPE produces a significantly high level of NO that contributes to increased apoptotic cell death detected by propidium iodide and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining. It is also associated with the depletion of intracellular glutathione (GSH), probably due to increased consumption by NO with the formation of S-nitrosoglutathione. Co-treatment with L-NAME, a NO synthase inhibitor, results in reduction of NO and apoptotic cell death. The decline in reduced GSH/oxidized GSH (GSSG) ratio is also reversed. N-Acetylcysteine, a thiol compound that reacts directly with NO, can reduce the increased NO generation and reverse the decreased GSH/GSSG ratio, thereby attenuating the cytotoxicity induced by high-dose GSPE. Taken together, these results suggest that endogenous NO synthase (NOS) activation and excessive NO production play a key role in the pathogenesis of high-dose GSPE-induced cytotoxicity.

Background: Previously, we have found that dust mite allergens can directly activate alveolar macrophages (AMs), induce inflammatory cytokines, and enhance T-helper type 2 cytokine production. A molecule of innate immunity in the lung, surfactant protein D (SP-D), is able to bind mite allergens and alleviates allergen-induced airway inflammation., Objectives: This study was aimed at investigating the activation pathway of mite allergen (Dermatophagoides pteronyassinus, Der p)-induced nitric oxide (NO) production by AMs, and the role of SP-D in the modulation of activated AMs by mite allergens., Methods: Porcine SP-D was purified from bronchoalveolar lavage fluids of Lan-Yu mini-pigs, by affinity chromatography on maltose-sepharose. NO production, inducible expression of lipopolysaccharides (LPS)-related binding and responding surface receptors complex, CD14 and toll-like receptor 4 (TLR4), as well as inducible NO synthase (iNOs) and nuclear factor-kappaB activation were studied in two AMs cell lines, MH-S (BALB/c strain),and AMJ2-C11 (C57BL/6 strain), and one peritoneal macrophage cell line (RAW264.7), after stimulation with LPS, or Der p., Results: LPS and Der p elicited different responses of NO production in the different cell lines, and the response might depend upon the expression of the cell surface CD14/TLR4 complex in different genetic backgrounds of macrophage cell lines. Pretreatment of macrophages with SP-D could inhibit NO production from Der p or LPS-stimulated alveolar macrophages., Conclusion: Mite allergen-induced alveolar macrophage activation is mediated by CD14/TLR4 receptors and can be inhibited by SP-D; it further supports the concept that SP-D may be an important modulator of allergen-induced pulmonary inflammation.

As a part of our study on the use of isotopic analogues as the internal standard (IS) for the quantitation of drug analytes, this article reports on the performance characteristics of 2H5-butalbital and 13C4-butalbital with particular focus on (1) determining and comparing the effectiveness of the 2H- and 13C-analogues in serving as the ISs for quantitation; (2) understanding the "cross-contribution" phenomenon underlying the effectiveness of selected ion pairs used for quantitation purpose; and (3) examining whether the same characteristics, observed in our preliminary report for the secobarbital/2H5-secobarbital/13C4-secobarbital system, also exist in the butalbital/2H5-butalbital/13C4-butalbital system. Adapting similar procedures applied to our previous study on the secobarbital system, we observed that (1) both labeled analogues (13C4-butalbital and 2H5-butalbital) cause more significant cross-contributions to ions designated for butalbital than butalbital to the labeled analogues; (2) compared to 2H5-butalbital, 13C4-butalbital appears to cause less cross-contributions to ions designated for butalbital; (3) cross-contribution between the following ion pairs are minimal: m/z 200/196, 199/195, 185/181 (13C4-butalbital as the IS) and m/z 201/196 (2H5-butalbital as the IS). It is also concluded that the butalbital/2H5-butalbital system exhibits the same concentration dependency phenomenon observed in the secobarbital/ 2H5-secobarbital system, that is, ratios of ion pairs designated for these two isotopic analogues (resulting from routine gas chromatography-mass spectrometry protocol) increase as their concentrations are diluted. (In parallel with the secobarbital/13C4-secobarbital system, the butalbital/13C4-butalbital system does not exhibit this phenomenon.)

Isotopic analogs of the analytes are currently preferred internal standards (IS) for quantitative analyses of drugs and their metabolites in biological matrices by GC/MS procedures. Contributions of the analyte and the IS to the intensities of ions designated for the IS and the analyte, respectively--an undesirable phenomenon termed "cross-contribution"--greatly weakens the effectiveness of this approach. The cross-contribution phenomenon has been, in the past, evaluated by a "direct measurement" approach, in which intensities of interested ions were measured in two separate experiments using equal quantities of the analyte and the IS. Alternate procedures that may generate improved results are hereby studied. For the "improved direct measurement" approach, ion intensity data derived from the previously reported direct measurement procedure are first normalized before being used to calculate the extent of cross-contribution. An "internal standard" approach is also developed, in which a set amount of a third compound is incorporated into these two separate experiments, thus allowing corrections of ion intensity data that are imbedded with variations inherent to separate experiments. Finally, a "standard addition" approach, involving a series "addition" of "standards", generates multiple data points; thus, providing a mechanism to validate the resulting cross-contribution data. Secobarbital/(2)H(5)-secobarbital and secobarbital/(13)C(4)-secobarbital pairs are adapted as the exemplar systems for this study.

Background and Purpose: To investigate the clustering of insulin resistance syndrome with hyperinsulinemia, hypertriglyceridemia, low high-density lipoprotein (HDL) cholesterol, hypertension, and obesity, we conducted this cross-sectional study and analyzed the patterns of conditional independence among these five elements., Methods: Fasting insulin, lipid profiles, blood pressure, and anthropometric data from 2165 Taiwanese older than 35 years in the Chin-Shan community were examined. The cut-off points of these five factors (all binary variables) were defined. The hierarchical log-linear regression with nested effects model was applied to fit this higher-order contingency table of five variables, and likelihood ratio (chi2) statistics were used to test the goodness of fit., Results: Hyperinsulinemia was independently correlated with obesity (odds ratio [OR] 5.7, 95% confidence interval [CI] 4.5-7.3), low HDL (OR 2.3, 95% CI 1.8-2.9), and hypertriglyceridemia (OR 1.6, 95% CI 1.2-2.2). Hypertriglyceridemia was significantly associated with low HDL (OR 3.6, 95% CI 2.7-4.8), and non-significantly associated with hypertension (OR 1.3, 95% CI 0.9-1.7) and obesity (OR 1.1, 95% CI 0.8-1.6). In persons with normal triglyceride levels, hypertension was positively associated with obesity (OR 2.8, 95% CI 2.1-3.7) and low HDL (OR 2.0, 95% CI 1.5-2.8). Analyses from forward and backward selection methods gave similar results. Graphical models with conditional independence relationships among these five variables were demonstrated., Conclusions: The components of insulin resistance syndrome have intricate relationships. Hyperinsulinemia was most related to obesity, and hypertriglyceridemia was most related to low HDL.

The Internet has changed the way people shop, do business, and communicate with one another. Even those who try to avoid computers are bombarded with Web advertisements on television and in newspapers and magazines. The Internet also has excellent, but still largely underused, potential for conducting research studies. A Web-based questionnaire essentially combines the power and graphic flexibility of a computer with the freedom of a mail survey. The specific goals of this study were (1) to develop a Web-based utility assessment tool and (2) to use this tool to measure the health burden of breast hypertrophy by using the Internet to sample a population. An open-enrollment, Internet-based survey was developed to assess societal preferences for mild and severe breast hypertrophy using three established assessment techniques: visual analogue scale, time trade-off, and standard gamble. Subjects were recruited from a Web-based clinical trial listing service. Demographics, subjects' utility for their current health, and responses to a comorbidity index were also recorded. Data were recorded from August 1, 1999, to January 31, 2000. There were 480 unique responses, and 356 (74 percent) met the inclusion criteria. The respondents were predominantly female (81 percent), Caucasian (83 percent), and in the middle income brackets. Their mean age was 32.9. The average score for capacity of understanding was 4.99 out of 5 (5 = excellent). The median utility score for severe breast hypertrophy (visual analogue scale, 0.70; time trade-off, 0.85; standard gamble, 0.88) differed significantly from the median utility score for mild breast hypertrophy (visual analogue scale, 0.93; time trade-off, 1.0; standard gamble, 0.98) for each method. The results showed that the construction of a Web-based questionnaire for utility assessment is feasible and can be used to capture the utility of health states. The authors were able to enroll a large number of subjects with excellent capacity to understand the study, resulting in a high rate of usable responses. The applicability of these data to cost-effectiveness studies is limited by the extent to which the sampled population of this study is representative of society in general. The demographics of this study sample also differed from those of the Internet population. The study was piloted by measuring the values for breast hypertrophy, but the procedure could be used to assess the burden on quality of life of any disease and, potentially, the efficacy of surgical interventions. The study method is recommended as an accurate and cost-effective alternative for measuring quality of life.

In order to identify arsenic as one of the major factors that cause Blackfoot disease on the southwest coast of Taiwan, an atomic absorption spectrophotometric method was used to determine arsenic, selenium and iron concentrations in the tissue of plantar digital arteries. Samples from 31 patients with Blackfoot disease and 30 controls with road traffic accident or occupational injuries were studied. The results indicate that the arterial tissue from Blackfoot disease patients had higher arsenic concentration (3.06+/-1.42 microg/g) than that from healthy controls (0.59+/-0.28 microg/g). The variability was very large 418% at p<0.001. It was also noted that the concentrations of selenium (1.23+/-0.41 microg/g and 1.05+/-0.13 microg/g in patients and controls respectively; with variability 17.1%) and iron (72.7+/-34.9 microg/g and 35.2+/-16.5 microg/g in patients and controls respectively; with variability 106.5%) were both higher than those of controls. However, only the iron concentration was significantly different (p<0.05).

Household waste collectors (HWCs) are potentially exposed to a variety of bioaerosols and toxic materials. Collection of household waste is also a job which requires repeated heavy physical activity such as lifting, carrying, pulling, and pushing. The object of this study was to assess whether there is an excess of adverse health outcomes among HWCs. The subjects were all current employees of the Household Waste Collection Department in the County of Kaohsiung, Taiwan. The survey questionnaire was completed by 533 HWCs and 320 office workers. Our data indicate that household waste collection presents a risk for the development of chronic respiratory symptoms (cough, phlegm, wheezing, and chronic bronchitis), musculoskeletal symptoms (low back pain and elbow/wrist pain), and injuries caused by sharp objects.

Triptolide (PG490), a diterpene triepoxide, is a potent immunosuppressive agent extracted from the Chinese herb Tripterygium wilfordii. We have previously shown that triptolide blocks NF-kappaB activation and sensitizes tumor necrosis factor (TNF-alpha)-resistant tumor cell lines to TNF-alpha-induced apoptosis. We show here that triptolide enhances chemotherapy-induced apoptosis. In triptolide-treated cells, the expression of p53 increased but the transcriptional function of p53 was inhibited, and we observed a down-regulation of p21(waf1/cip1), a p53-responsive gene. The increase in levels of the p53 protein was mediated by enhanced translation of the p53 protein. Additionally, triptolide induced accumulation of cells in S phase and blocked doxorubicin-mediated accumulation of cells in G(2)/M and doxorubicin-mediated induction of p21. Our data suggest that triptolide, by blocking p21-mediated growth arrest, enhances apoptosis in tumor cells.

Aortic dissection complicated with limb and visceral ischemia is a clinical dilemma since surgical intervention carries high risk of morbidity and mortality. The management is further complicated when renal perfusion is impaired and thus associated with severe renovascular hypertension. As catheterization techniques advanced over the past decade, percutaneous endovascular intervention provides a less invasive alternative for management of such cases. We report a case of chronic Stanford type B aortic dissection complicated with visceral and limb ischemia presenting with marked renovascular hypertension, which was successfully treated with percutaneous endovascular aortic stenting.

Idiopathic ventricular fibrillation (VF) is extremely rare in children who have not previously undergone cardiac surgery. Patients resuscitated from idiopathic VF remain at risk for recurrence. The use of an implantable cardioverter-defibrillator (ICD) effectively prevents such recurrences. We report the case of a 12-year-old girl who had a history of recurrent syncope and had survived an episode of VF. Serial studies after prolonged but successful resuscitation, including echocardiography, an electrocardiogram (ECG), and coronary angiography failed to reveal abnormal cardiac structures responsible for VF. No abnormal conduction pathways or abnormal early or late after depolarization were found on electrophysiologic study. The ST segments of the 12-lead ECG remained normal after procainamide challenge. The patient underwent ICD implantation 2 weeks after admission and syncope did not recur during a follow-up of 14 months. This report emphasizes that idiopathic VF may be responsible for syncope in children. ICD therapy prevents the recurrence of idiopathic VF and the associated risk of sudden death.

Use of an isotopic analogue of the analyte as the internal standard in a quantitative gas chromatography-mass spectrometry targeted-compound-analysis protocol is often hindered by the availability of an adequate number (typically three for the drug/metabolite and two for the isotopic analogue) of sufficiently high mass ions that can be attributed to each member of the pair and are sufficiently free of interference by the contribution from the other component of the pair, a phenomenon termed "cross-contribution". Methamphetamine (MA) is selected as the exemplar compound to examine the effectiveness in using different chemical derivatization routes to produce derivatized analyte-isotopic analogue pairs that can generate more favorable mass spectrometric data to meet this analytical requirement. Trimethylsilyl-, trichloroacetyl-, and pentafluoropropionyl-derivatization and MA-d5, MA-d8, and MA-d9 are studied. Data resulting from this study indicate that the number of ion pairs suitable for quantitation and the degree of cross-contribution of these ions vary significantly. These data empirically demonstrate that derivatization methods play a significant role in deciding which deuterated analogue of the analyte provides the most suitable ion pairs that cause the least cross-contribution. The most suitable internal standard varies with the derivatization route adapted for an analytical protocol.

Ventricular tachycardia is a rare complication of dipyridamole stress testing. We present a case in which dipyridamole induced symptomatic ventricular tachycardia. The patient, a 41-year-old man with a history of chest discomfort on exertion for 1 year, underwent dipyridamole thallium imaging. Sustained ventricular tachycardia occurred 1 minute and 40 seconds after completion of the dipyridamole infusion. Intravenous aminophylline (125 mg) was given immediately and the tachycardia was terminated. Two minutes later, thallium-201 was injected and subsequent myocardial imaging showed reversible perfusion defects in the inferior wall, septum, and apex. Coronary angiography revealed three-vessel disease. This case discloses that reversible perfusion defects can still be demonstrated on thallium scan in spite of injection of aminophylline, an antagonist of dipyridamole, before thallium administration.

The gene encoding spermidine synthase (spsA) was isolated from Dictyostelium discoideum using the technique of insertional mutagenesis. Northern blot analysis showed that the spsA mRNA is expressed maximally during the vegetative stage and decreases gradually during the 24 h of development. Sequencing of the genomic DNA and a full-length cDNA clone indicated the presence of one intron in a gene coding for a predicted protein (SpsA) with 284 amino acids. The sequence is highly conserved, with amino acid identities compared to spermidine synthases of humans, 59.5%, to mouse, 61.3%, and to yeast, 58.1%. A null mutant of the spsA gene is unable to grow in the absence of exogenous spermidine. Development of spsA null cells grown in the absence of spermidine produced fruiting bodies that have abnormally short stalks.

Terminal differentiation of both stalk and spore cells in Dictyostelium can be triggered by activation of cAMP-dependent protein kinase (PKA). A screen for mutants where stalk and spore cells mature in isolation produced three genes which may act as negative regulators of PKA: rdeC (encoding the PKA regulatory subunit), regA and rdeA. The biochemical properties of RegA were studied in detail. One domain is a cAMP phosphodiesterase (Km approximately 5 microM); the other is homologous to response regulators (RRs) of two-component signal transduction systems. It can accept phosphate from acetyl phosphate in a reaction typical of RRs, with transfer dependent on Asp212, the predicted phosphoacceptor. RegA phosphodiesterase activity is stimulated up to 8-fold by the phosphodonor phosphoramidate, with stimulation again dependent on Asp212. This indicates that phosphorylation of the RR domain activates the phosphodiesterase domain. Overexpression of the RR domain in wild-type cells phenocopies a regA null. We interpret this dominant-negative effect as due to a diversion of the normal flow of phosphates from RegA, thus preventing its activation. Mutation of rdeA is known to produce elevated cAMP levels. We propose that cAMP breakdown is controlled by a phosphorelay system which activates RegA, and may include RdeA. Cell maturation should be triggered when this system is inhibited.

The duration of a positron emission tomography (PET) imaging scan can be reduced if the transmission scan of one patient which is used for emission correction can be synthesized by using the reference transmission scan of another patient. In this paper, we propose a new intersubjects PET emission scan registration method and PET transmission synthesis method by using the boundary information of the body or brain scan of the PET emission scans. The PET emission scans have poor image quality and different intensity statistics so that we preprocess the emission scans to have similar histogram and then apply the point distribution model (PDM) [15] to extract the contours of the emission scan. The extracted boundary contour of every slice is used to reconstruct the three-dimensional (3-D) surface of the reference set and the target set. Our registration is 3-D surface-based which uses the normal flow method [17] to find the correspondence vector field between two 3-D reconstructed surfaces. Since it is difficult to analyze internal organ using the PET emission scan imaging without correction, we assume that the deformation of internal organ is homogeneous. With the corresponding vector field between the two emission scans and the transmission scan of the reference set, we can synthesize the transmission scan of the target set.

The production of chitinolytic enzyme by Pseudomonas aeruginosa K-187, using shrimp and crab shell powder (SCSP) as the carbon source, was studied. It was observed that chemically treated SCSP induced a significant increase of enzyme production, as compared with untreated SCSP. Spent HCl and NaOH from the chitin production industry was used to process SCSP. Various strategies of SCSP processing are examined and compared in terms of chitinolytic enzyme production. A three-and-one-half-fold increase of enzyme production (0.68 U/ml to 2.4 U/ml) was attained using HCl/NaOH treated SCSP. The microorganism (K-187) was isolated from soil in Taiwan and has been characterized and reported in a previous paper.

Using insertional mutagenesis, we have isolated a "stalky" mutant in which cells destined to become spores end up as stalk cells. Similar mutants were previously observed after chemical mutagenesis, but the affected gene could not be isolated. Our mutant, like the previous ones, is in stkA. Its defect is cell-autonomous and not overcome by overexpressing cAMP-dependent protein kinase. stkA is strongly expressed in the prespore region of aggregates but not in the anterior prestalk zone. The mutant expresses normal levels of prespore-cell transcripts but fails to produce the spore transcript spiA. stkA encodes a predicted 99 kDa protein (STKA) with two putative C4 zinc fingers, one of which is a GATA-type finger, indicating that it may be a transcription factor. This conclusion is supported by localization of STKA in the nucleus.

Point mutations of the K-ras gene have been reported in a wide variety of human tumors. By using polymerase chain reaction followed by direct DNA sequencing, we screened for point mutations at codons 12 and 13 of the K-ras gene in specimens obtained from fresh frozen tumors in 38 patients with non-small cell lung cancers. Point mutations were detected in two of 38 (5.3%) resected non-small cell lung cancers. Both of them were G to T transversions. One patient was found to have a K-ras codon 13 point mutation (GGC to TGC, gly to cys), while the other had a codon 12 point mutation (GGT to GTT, gly to val). Based on the limited numbers in this study, we found that the frequency of K-ras point mutations in codons 12 and 13 among Asian patients with lung adenocarcinomas was lower than that detected among Caucasian patients.

Botryllus schlosseri is a clonally modular ascidian in which asexually derived adults (zooids) exhibit developmental synchrony. At the conclusion of the blastogenic (asexual) cycle every 5 days at 21 degrees C, all zooids within a colony die simultaneously in 24 hours and are replaced by a new asexual generation of zooids. This cyclical process, called takeover, involves the selective destruction of the zooid's visceral tissues which include the pharynx, esophagus, stomach, intestine, endostyle, neural complex and heart, whereas bud tissues and mesenchymal components (muscle and blood cells) remain unaffected. Ultrastructural analysis indicates that the most prevalent form of cell death occurs by apoptosis, although necrotic changes are also observed in several tissues (i.e., stomach and intestine). Blood-derived macrophages and neighboring cells subsequently engulf visceral tissues, reducing the zooid to the size of a small vesicle. Here, we have tested the possibility that acid phosphatase, a hydrolase whose presence is associated with cell death in several invertebrate systems, could account for some of the regressive changes observed during takeover. Our observations indicate that acid phosphatase (AP) activity was selectively localized in the gut of parent zooids during the growth phase of the cycle, with the stomach exhibiting the most intense histochemical staining on tissue sections. As zooid regression progressed during takeover, stomach AP staining gradually disappeared. Other visceral tissues never became AP-positive. Therefore, this hydrolase appears to play a minimal role in zooid death. In order to characterize genes whose expression pattern was selectively altered during takeover, we have carried out differential mRNA display analysis. We report on two genes, 790.3 and 790.4, that are down- and upregulated, respectively, during this process. Collectively, these findings indicate that the takeover phase of blastogenesis in Botryllus involves modulated gene expression.

Background: Buried penis is a congenital abnormality in which the phallus is concealed within the surface of prepubic skin. It is probably more common than is generally recognized. The objective was to describe the pathophysiology, and search for the best management of this disease., Methods: Over a period of 6 years, a total of 31 cases receiving surgery for buried penis at this hospital were analyzed. According to their major pathophysiology, patients were divided into three groups: in the first, the major mechanism was poor skin suspension; in the second, prominent suprapubic fat pad was the major cause. In the third group, the dartos fascia was abnormally thickened and attached to the penile shaft. Different surgical techniques were applied in the different groups., Results: All 15 children in the first group had satisfactory results after penile skin fixation. In the second group, nine children underwent adjunctive lipectomy but only five had satisfactory results. Seven patients in the third group needed degloving of the penis and the three cases who underwent preputial unfurling had severe lymphedema of the inner preputial layer. One of them received revision. The end results were good in the other six patients after long-term follow up., Conclusions: The buried penis occurs in a spectrum. Although, there are three major pathophysiology mechanisms, most of the patients had a combination. Surgical management should be individualized, and results are usually satisfactory. For the obese patient, weight loss is important. Preputial unfurling and using inner preputial layer to cover the defect should be avoided because of severe postoperative lymphedema.

Since the advent of routine antenatal sonography to detect fetal abnormalities, two cases of choledochal cyst have been found prenatally in our hospital. The first presented when a choledochal cyst was demonstrated at 31 weeks of gestation, and a firm diagnosis established within 2 days of birth. Technetium 99m disofenin (DISIDA) cholescintigram revealed delayed visualization of the small bowel. The second case was found by ultrasound examination at 21 weeks of gestation to have a choledochal cyst, and diagnosis was confirmed within 3 days of birth. DISIDA scintigram demonstrated complete obstruction of the extrahepatic biliary tree. Both infants received early excision of the cyst at the ages of three and four days respectively. The postoperative course was quite smooth, and there were no abnormal symptoms after follow up of four and two years, respectively. Neonates with distal common bile duct obstruction in association with presumed choledochal cyst should have prompt surgical exploration, and early excision of the cyst is a safe procedure in the newborn.

Recently an insertional mutagenesis procedure has been developed to permit cloning of genes affected in developmental mutants of Dictyostelium discoideum (Kuspa and Loomis, Proc. Natl. Acad. Sci. USA 89, 8803-8807, 1992). In this procedure a plasmid bearing the URA (pyr5-6) gene is linearized with a restriction enzyme and electroporated into URA- amoebae (auxotrophic for uracil) together with the corresponding restriction enzyme. Transformants that can grow without uracil are screened for developmental defects resulting from insertion of the plasmid into a gene of developmental importance. We have modified this procedure to permit characterization of the promoters and structural sequences of genes that would be missed by the standard procedure because their disruption produces no obvious phenotype. Constructs carrying a promoter-less Escherichia coli lacZ gene were designed so that expression of lacZ requires insertion into an active host transcription unit. By screening restriction enzyme-generated transformants we have isolated several strains in which lacZ is under the control of a developmentally activated promoter and have cloned the 5' flanking DNA adjacent to the insertion site. Sequencing the junction between plasmid and host genome has confirmed in-frame fusion with the lacZ gene, and reintroduction of the cloned plasmids into parental cells has shown that the cloned sequences do actually contain the relevant promoters. This procedure should give ready access to a wide range of developmental promoters without the need for prior identification of the developmental genes involved.

Background: Jejunoileal atresia is the most common intestinal atresia and the most frequent cause of neonatal intestinal obstruction. The prognosis depends on several important factors. The patients reported were collected for evaluation of the factors contributing to their prognoses., Methods: In the ten-year period from October 1982 to October 1992, all jejunoileal atresia patients who received treatment in this hospital were entered in this study. Possible factors contributing to prognosis, such as prematurity, low birth weight, apple peel atresia, anastomotic leakage, sepsis, short bowel syndrome were evaluated using Mann-Whitney U-test., Results: Twenty-four patients of jejunoileal atresia had been managed in our hospital in 10 years period. Their ages ranged from one to thirteen days old (mean 3.9 days). The numbers and types of atresia were as follow: type I (n = 4), type II (n = 4), type IIIa (n = 10), type IIIb (n = 5), type IV (n = 1). All patients received surgical correction. Nine complications were found in eight patients, which included four anastomotic leakage, three wound infections and two intestinal obstructions. There were three mortalities from sepsis. Total parenteral nutrition was applied to 14 patients (58.3%). The mean hospital stay was 45.1 days, and the survival rate was 87.5%. Low birth weight and anastomotic leakage contributed to prolonged hospital stays (p < 0.05)., Conclusions: Jejunoileal atresia is a common neonatal surgical condition. The prognosis is generally good, except when a patient presented with factors, such as, low birth weight or anastomotic leakage, which prolonged hospital stays. Moreover, sepsis is the only important factor contributing to mortality.

From 1985 to 1993, five male patients with posterior urethral valves were treated at our hospital; they included three newborns, a 32-month-old and a 10-year-old child. On initial examination, all patients showed severe bilateral hydronephrosis and hydroureter on sonographic findings, dilatation of the prostate urethra and trabeculation of the bladder wall in the voiding cystourethrogram; only one patient showed vesicoureteral reflux. Type I urethral valves were present in all patients. Retrograde transurethral ablation of the valves was performed in four patients with good preoperative renal function. The postoperative courses were smooth except for vesicoureteral reflux in one patient and systemic fungus infection in another. Reimplantation of the ureter was done for the vesicoureteral reflux, and the fungus infection was treated by amphotericin B. Cutaneous vesicostomy was performed for a newborn since the urethral orifice was small. He presented with poor renal function and ascites. Delayed antegrade ablation of the valves per vesicostomy and closure of the vesicostomy were done three months later after restoration of the renal function. Renal function returned to normal after operation in all patients, but the function of the upper urinary tract and bladder continence need long-term follow-up.

Shrimp and crab shell powder prepared by treating shrimp and crab processing waste with boiling and crashing was used as a substrate for isolating alkali-tolerant chitinolytic microorganisms. Strain K-187 appeared to be the chitinase-producing strain with the most potential. The organism was identified as a strain of Pseudomonas aeruginosa. Maximum chitinase activity was obtained when the strain was grown aerobically in a medium consisting of 3.0% shrimp and crab shell powder, 0.1% CMC, 0.1% (NH4)2SO4, 0.1% K2HPO4, 0.1% MgSO4.D7H2O and 0.1% ZnSO4 (pH 9), at 45 degrees C after 3 days. The optimum pH and temperature of the enzyme reaction were 7 and 40 degrees C, respectively. The chitinase was stable at pH from 5 to 10 and was stable under 60 degrees C.

Primary aldosteronism caused by an aldosterone-producing adrenal adenoma was documented in an 11-year-old girl who presented with persistent hypertension, headache, tinnitus and hypokalemia. Elevated plasma aldosterone concentration (PAC) (45.5 ng/dl) and suppressed plasma renin activity (PRA) (< 0.3 ng/ml/hrs) were detected. Saline infusion test and postural test helped to confirm the diagnosis. The tumor site was localized by magnetic resonance imaging (MRI). Surgical removal of the tumor yielded dramatic improvement in blood pressure; PAC and PRA returned to normal range. This rare case illustrates the feasibility of recognition and localization of adrenal adenoma in children. The high cure rate by surgical excision warrants careful screening of hypertensive patients with this entity.

An 81-year-old patient who developed consciousness change and progressive right limb weakness after low abdominal surgery is reported. Brain computed tomography scan showed a left-sided chronic subdural hematoma; appropriate management was instituted immediately. This case is a reminder of the possibility of chronic subdural hematoma in elderly patients who may develop stroke-like symptoms after non-neurosurgical procedures.

Congenital duodenal webs are rare lesions, usually detected during early infancy because of signs of high intestinal obstruction. The occasional patient escapes both symptoms and detection until adolescence or adulthood. This report concerns two cases of congenital duodenal web at different ages and with different clinical manifestations. Case 1, a six-month-old male, was admitted because of abdominal distention and vomiting. Case 2, a 13-year-old boy, was referred here for further evaluation of recurring seizure attacks, elevated blood urea nitrogen and creatinine and hyponatremia. Duodenotomy and excision of the web performed for both patients. Complete amelioration of all symptoms was then observed at Outpatient Clinic follow-up for one year.

Background: Gastrointestinal perforation is an infrequent occurrence in neonates. Experience in its management is presented, while also attempting to analyze the factors affecting outcome., Methods: From 1983 to 1992, 31 neonates with gastrointestinal perforation were treated at Taichung Veterans General Hospital. The medical records of these patients were reviewed thoroughly. In the meantime, Mann-Whitney U and Yates' correction chi square tests were used to analyze the factors predicting the outcomes., Results: There were 21 males and 10 females, among whom 16 were premature births. The median age at diagnosis was 5 day; half (16/31) had occurred during the first 5 days of life. Abdominal distension was the most common manifestation (87%). Hemograms at admission showed leukopenia in 32% (10/31) and thrombocytopenia in 40% (8/20) of the patients. Metabolic acidosis was present in 46% (13/28) of the patients. Peritoneal fluid and preoperative blood cultures were positive in 71% (17/24) and 50% (13/26) of the patients, and both of them had Gram-negative enterobacteriacea as the most common pathogen. The overall mortality rate was 58%. The highest mortality rate was associated with gastric perforation (100%), followed by small bowel (50%) and colon (50%) perforations. The predominant cause of perforation was necrotizing enterocolitis (14/31), with the most common site the terminal ileum (16/29). Four patients with necrotizing enterocolitis had multiple perforations. Others who underwent surgery showed single perforation. The major cause of death in those patients who received operation was sepsis (8/13). An initial arterial pH value higher than 7.25, and surgical procedure performed within two days after disease onset may predict a favorable outcome (p < 0.01)., Conclusions: Gastrointestinal perforation is a life-threatening complication in neonates. A better survival rate can be obtained by cooperation among neonatologists, pediatric surgeons and the nursing staff taking care of these high risk babies.

Flame atomic absorption spectrophotometric methods were developed for, arsenic, selenium, copper, zinc and iron in hair samples. Data from blackfoot disease patients at five clinical stages were compared with those from healthy controls. The copper and zinc concentrations showed only slight differences in all clinical stages, which indicated the less relation to blackfoot disease. The decrease of selenium and iron in all stages was attributed to the antagonistic effect of arsenic; arsenic increased in the first and second stages, but decreased in the later stages. The decrease of selenium and iron during the progression of the disease is thought to be due to persistence of the antagonistic effect of arsenic in the initial stages, so that very low concentrations of selenium are found in the advanced stages, despite the later decrease of arsenic. There was also a progressive decrease of iron with advance of the disease, and the later stages also showed a decrease in haemoglobin. It was shown that arsenic is a major cause of blackfoot disease, and that it antagonises selenium and iron, which decreased in the advanced clinical stages of the disease.