Longitudinal changes in physical and mental health of older adults with chronic hepatitis B infection: Trajectories and predictors

Despite the increasing health burden of chronic hepatitis B (CHB) in aging populations, little is known about the course of health-related quality of life (HRQoL) changes. We aimed to assess individual-level longitudinal HRQoL changes in elderly patients with CHB and to examine their correlates. A prospective 5.1 years-cohort study was conducted in community-dwelling adults aged 55 years with hepatitis B surface antigen-positive. Participants underwent serial measurement of HRQoL using the short-form (12) health survey version 2. Of 503 participants, 82.7% remained in good physical health throughout the study period, whereas 9.1% had declining physical health and 8.2% were in poor physical health. We likewise identified three trajectories of mental health changes ("good mental health" [86.9%], "declining mental health" [6.8%], and "poor mental health" [6.4%]). Three baseline characteristics were independently associated with a lower likelihood of remaining physically or mentally healthy: sarcopenic obesity (odds ratio [OR] with 95% confidence interval [95% CI] of 7.5 [2.8-20.5] for poor physical health, 3.1 [1.1-8.4] for declining physical health, 4.3 [1.4-13.0] for poor mental health), a higher number of metabolic abnormalities (OR [95% CI] of 3.6 [1.6-8.0] for poor physical health) and depressed mood (OR [95% CI] of 21.7 [5.8-81.0] for poor physical health, 5.3 [1.4-19.9] for declining physical health, 83.1 [19.7-350.2] for poor mental health, 13.6 [2.9-64.8] for declining mental health). In conclusion, in a cohort of elderly patients with CHB, we demonstrated the heterogeneity and nonlinearity of HRQoL changes and their associations with variations in specific extrahepatic organs/systems.

A comparison of hospital and community stay in patients who underwent compulsory admission before and after the 2007 Amendment to the Mental Health Act in Taiwan

OBJECTIVE

The main purpose of this study was to assess the empirical findings of compulsory admission for psychiatric disorders before and after the 2007 amendment to the Mental Health Act in Taiwan.

METHODS

A matched case-control study design was applied. Participants were selected using the National Health Insurance Research Database (NHIRD) in Taiwan. The control and case data were collected in 2006 and 2011, and the number of compulsory admission cases was recorded with a case-control ratio of 1:4, along with information on age (±3 years) and gender. In 2006, the number of patients recruited was 9265, including 1853 compulsorily admitted patients and 7412 voluntarily admitted patients. In 2011, the number of patients recruited was 4505, including 901 compulsorily admitted patients and 3604 voluntarily admitted patients.

RESULTS

The data collected for the patients who underwent compulsory admission before and after the amended Mental Health Act included gender, diagnosis, Charlson Comorbidity Index Score (CCIS), length of stay in an acute hospital ward (days), hospital accreditation level, ownership, teaching hospital status, psychiatrist gender and age, and hospital location. Although the number of compulsory admission cases (1853 vs. 901) markedly decreased and the length of stay in an acute hospital ward (30.7 ± 25.0 days vs. 39.0 ± 22.6 days) increased from 2006 to 2011, the readmission rate was reduced from 52.6% in 2006 to 42.5% in 2011.

CONCLUSIONS

The average lengths of hospital stay and community survival time were greater for compulsorily admitted patients than those for voluntarily admitted patients. This result might be attributed to a number of changes implemented since the 2007 amendment of the Mental Health Act, including a strict review process for compulsory admissions and a new discharge planning process, which require further research for approval.

Critical role of morphology on the dielectric constant of semicrystalline polyolefins

A particularly attractive method to predict the dielectric properties of materials is density functional theory (DFT). While this method is very popular, its large computational requirements allow practical treatments of unit cells with just a small number of atoms in an ordered array, i.e., in a crystalline morphology. By comparing DFT and Molecular Dynamics (MD) simulations on the same ordered arrays of functional polyolefins, we confirm that both methodologies yield identical estimates for the dipole moments and hence the ionic component of the dielectric storage modulus. Additionally, MD simulations of more realistic semi-crystalline morphologies yield estimates for this polar contribution that are in good agreement with the limited experiments in this field. However, these predictions are up to 10 times larger than those for pure crystalline simulations. Here, we show that the constraints provided by the surrounding chains significantly impede dipolar relaxations in the crystalline regions, whereas amorphous chains must sample all configurations to attain their fully isotropic spatial distributions. These results, which suggest that the amorphous phase is the dominant player in the context, argue strongly that the proper polymer morphology needs to be modeled to ensure accurate estimates of the ionic component of the dielectric constant.

[A pilot study of the professional autonomy, job satisfaction, and related factors of nurses at a regional hospital]

BACKGROUND

Professional autonomy often causes confusion in nursing staffs that limit their ability to perform to the best of their professional capabilities. Moreover, heavy and busy workloads reduce the energy available for work resulting in lower working efficiency and lower job satisfaction.

PURPOSE

This study explores the status and factors related to professional autonomy and job satisfaction in nurses.

METHODS

A cross-sectional design was used to target the nurses employed at a regional hospital in southern Taiwan. Data on locus of control, professional autonomy, and job satisfaction were collected for analysis.

RESULTS

Data were collected from 207 nurses, with 196 valid responses (response rate: 94.69%). One hundred and forty-six subjects (74.5%) were found to have an internal locus of control personality type. Scores for both professional autonomy and job satisfaction were above the "moderate" level (averages: 3.37 and 3.32, respectively, on a maximum scale of 5). Social demographic differences contributed to the variance in professional autonomy and job satisfaction among participants. Professional autonomy was found to be positively associated with job satisfaction.

CONCLUSIONS

The findings of this study indicate that nurses with an internal locus of control personality exhibit higher professional autonomy and job satisfaction and that higher professional autonomy is associated with higher job satisfaction.

Gallstone disease and the risk of stroke: a nationwide population-based study

BACKGROUND

Gallstone disease (GD) and stroke share a number of risk factors including diabetes and hyperlipidemia. This nationwide population-based study was designed to estimate the risk of stroke after a diagnosis of GD.

METHODS

Data were obtained from the Taiwan National Health Insurance Research Database. A total of 135,512 patients with a diagnosis of GD and 271,024 age- and gender-matched non-GD control patients were included to assess the risk of stroke using Cox proportional hazard regression.

RESULTS

During the study period (2000-2003), 12,234 (153.67/10,000 person-years) strokes occurred among the GD patients, and 20,680 (114.83/10,000 person-years) among the controls. The diagnosis of GD carried a higher risk of developing ischemic and hemorrhagic stroke, with a hazard ratio (HR) of 1.28 and 1.33 (95% confidence interval [CI], 1.25-1.31 and 1.25-1.41, both P < .0001), respectively. Stroke risk was increased in both genders but at a higher rate in younger age. The GD group had significantly higher prevalence rate of comorbidities that are known stroke risk factors, including hypertension, diabetes, and coronary artery disease. Stroke risk was higher in the GD group with or without any of these comorbidities.

CONCLUSIONS

In this population-based longitudinal follow-up study, GD carried a significantly higher stroke risk, particularly for younger age with or without stroke risk factors. Stroke preventive measures maybe needed for patients with GD, especially those of younger age and with stroke risk factor(s).

Is low individual socioeconomic status (SES) in high-SES areas the same as low individual SES in low-SES areas: a 10-year follow-up schizophrenia study

OBJECTIVE

This study investigates the relationship between individual and neighborhood socioeconomic status (SES) and mortality among patients with schizophrenia.

METHODS

A study population was identified from the National Health Insurance Research Database (NHIRD) prior to the end of 1999 that included 60,402 patients with schizophrenia. Each patient was tracked until death or to the end of 2009. Individual SESs were defined by enrollee category. Neighborhood SES was defined by enrollee category (as a proxy for occupation) and education, which were classified according to the conventions of Hollingshead. Neighborhoods were also grouped into advantaged and disadvantaged areas. The Cox proportional hazards model was used to compare the death-free survival rate between the different SES groups after adjusting for possible confounding factors and risk factors.

RESULTS

During the 10-year follow-up period, the mortality rates among high, moderate, and low individual SES groups were 12.22, 14.75, and 18.48%, respectively (P < 0.001). Schizophrenia patients with low individual SESs in disadvantaged neighborhoods had a risk of death that was 18-22% higher than that of those with high individual SES in advantaged neighborhoods. The analysis of the combined effect of individual SES and neighborhood SES revealed that the death rates were highest among those with low individual SES and low neighborhood SES (P < 0.001).

CONCLUSIONS

Schizophrenia patients with low individual SES in disadvantaged neighborhoods have the highest risk of mortality despite a universal health-care system. Public health strategies and welfare policies must continue to focus on this vulnerable group.

Employing crisis postcards with case management in Kaohsiung, Taiwan: 6-month outcomes of a randomised controlled trial for suicide attempters

BACKGROUND

Suicide attempts constitute a serious clinical problem and have important implications for healthcare resources. The aim of the present study was to evaluate the effectiveness of case management using crisis postcards over a 6-month follow-up period.

METHOD

A randomised controlled trial was conducted in Kaohsiung, Taiwan. Prevention of further suicide attempts was compared between two groups with and without the postcard intervention. The intervention group consisted of 373 participants (139 males, 234 females; age: 39.8 ± 14.0 yrs.). The control group consisted of 388 participants (113 males, 275 females; age: 40.0 ± 16.0 yrs.). A survival analysis was used to test the effectiveness of the crisis postcard intervention for the prevention of suicide reattempts. Per-protocol and intention-to-treat analyses were conducted.

RESULTS

The intention-to-treat analysis indicated that the crisis postcard had no effect (hazard ratio = 0.84; 95% CI = 0.56 - 1.29), whereas the per-protocol analysis showed a strong benefit for the crisis postcard (hazard ratio = 0.39; 95% CI = 0.21 - 0.72).

CONCLUSION

Although the results of the present study indicated that the postcard intervention did not reduce subsequent suicide behaviour, our study provides an alteration to the postcard intervention. Further studies need to be conducted to clarify whether this type of intervention can reduce subsequent suicidal behaviour, with a particular focus on reducing the rate of loss to follow-up.

C-reactive protein concentration as a significant correlate for metabolic syndrome: a Chinese population-based study

Increasing evidence suggests that chronic, low-grade inflammation may be a common soil involving the pathogenesis of metabolic syndrome (MetS) and cardiovascular disease. We examined the association between C-reactive protein (CRP) concentration, an extensively studied biomarker of low-grade inflammation, and the MetS in a representative sample of Chinese adults in Taiwan. We performed a cross-sectional analysis of data from 4234 subjects [mean (±SD) age, 47.1 (±18.2) years; 46.4 % males] who participated in a population-based survey on prevalences of hypertension, hyperglycemia, and hyperlipidemia in Taiwan. CRP levels were measured by the immunoturbidimetric CRP-latex high-sensitivity assay. The MetS was defined by an unified criteria set by several major organizations. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated with logistic regression model. Overall, there were 938 subjects with MetS among 4,234 participants, resulting in a prevalence rate of 22.1 %. A significantly progressive increase in the prevalence of MetS across quartiles of CRP was observed (p for trend <0.001). Participants in the second, third, and upper quartiles of CRP had significantly higher risk of having MetS when compared with those in the lowest quartile [adjusted ORs (95 % CIs) were 2.18 (1.62-2.94), 4.39 (3.31-5.81), and 7.11 (5.39-9.38), respectively; p for trend <0.001]. Furthermore, there was a strong stepwise increase in CRP levels as the number of components of the MetS increased. The prevalence of MetS showed a graded increase according to CRP concentrations. The possible utility of CRP concentration as a marker for MetS risk awaits further evaluation in prospective studies.

The subjective sleep quality and heart rate variability in hemodialysis patients

INTRODUCTION

Sleep disturbances and cardiovascular autonomic dysfunction are major complications of hemodialysis (HD). The goal of this study is to identify clinical, heart rate variability (HRV) or laboratory parameters that are independently associated with subjective sleep quality.

PATIENT AND METHODS

Forty-six stable HD patients filled out sleep questionnaires - Pittsburgh sleep quality index (PSQI), Athens insomnia scale (AIS), and Epworth sleepiness scale (ESS). In addition, they received analyses of 5-minute HRV twice, in lying posture before and after HD. We also recruited 50 healthy subjects who received 5-min HRV.

RESULTS

The patients with end-stage renal disease have a high rate of poor sleep quality according to PSQI, AIS, and ESS. The activities of total power (0-0.5 Hz), high-frequency power (HF, 0.15-0.40 Hz), low-frequency power (0.04-0.15 Hz), and very-low-frequency power (0.003-0.04 Hz) in HD patients are obviously lower than that in the healthy people. The poor sleepers (PSQI > 5) show lower heart rate, higher HF and variance before HD, but did not show a significant difference after HD. There is no significant difference between HRV and global score of AIS, but the insomnia group (AIS > 5) has higher BMI. These patients with sleepiness (ESS > 9) only reveal lower hemoglobin, although the global score of ESS reveals no significant relationship with HRV.

CONCLUSION

HD patients have a high rate of poor sleep quality and autonomic dysfunction. Greater attention for the evaluation of sleep quality is needed for the better care of HD patients.

The effect of maternal betel quid exposure during pregnancy on adverse birth outcomes among aborigines in Taiwan

In considering documented developmental toxicity and teratogenicity found in earlier research, maternal betel quid chewing may very well be linked to a higher risk of adverse birth outcomes. The aim of this study was to investigate the significance of betel quid chewing, together with the use of cigarettes or alcohol, either independently or combined, on birth-related outcomes. A total of 1264 aboriginal women who had just given birth in 10 hospitals in Southern and Eastern Taiwan were recruited. Information on their maternal and newborn characteristics was obtained from medical charts and by performing personal interviews using a validated questionnaire. Maternal areca nut chewing during pregnancy was found to be significantly associated with both birth weight loss (-89.54 g) and birth length reduction (-0.43 cm). A significantly lower male newborn rate (aOR=0.62) was observed among aboriginal women with a habit of betel quid chewing during pregnancy. The use of this substance conveyed a 2.40- and 3.67-fold independent risk of low birth weight and full-term low birth weight, respectively. An enhanced risk (aOR=3.26-5.99) of low birth weight was observed among women concomitantly using betel quid, cigarette and alcohol during gestation. Our findings suggest that betel quid chewing during pregnancy has a substantial effect on a number of birth outcomes, including sex ratio at birth, lower birth weight and reduced birth length.

Stabilization of calpain large subunits by overexpression of truncated calpain small subunit in L8 myoblasts

The objectives were to investigate the function of the small subunit in the calpain system by expression of the autolytic form of this subunit in L8 myoblasts. Rat post-autolysis small subunit (21 kDa) cDNA expression plasmid was transfected into L8 myoblasts and selected by G418 containing medium. The concentrations of cytosolic micro-calpain in transfected cells, SS2 and SS3, were found to be 15.7 and 17.3% higher than that in L8Neo control cells, and the concentrations of cytosolic m-calpain in SS2 and SS3 cells were 23.3 and 16.6% higher than that in control cells (L8Neo). The half-life of micro-calpain in SS3 cells (36.5 h) was longer than that in L8Neo cells (32.4 h), while the half-life of m-calpain in SS3 cells (40.1 h) was longer than that in L8Neo cell (37.5 h). These results indicated that the expression of truncated small subunit increased the stability of micro- and m-calpain large subunits in cytosol.

Betel quid chewing and risk of adverse birth outcomes among aborigines in eastern Taiwan

It is known that substance abuse during pregnancy is associated with increased risk of adverse birth outcomes. The aim of this study was to determine the use of alcohol, cigarettes, betel quid, and drugs among pregnant aboriginal women and to assess the risk of adverse effects of betel quid use on birth outcomes in eastern Taiwan. Of a total of 229 women recruited into this study, 32 women with adverse birth outcomes constituted the case group. Analyses revealed that adverse birth outcomes were associated with maternal betel quid chewing and maternal age. After adjusting for maternal age, the risk of adverse birth outcome was five times higher among betel quid chewing women as compared to substance nonusers. Based on this finding, it is suggested health education, especially when concerned with the harmful effects of substance abuse, which includes betel quid use during pregnancy, should be stressed in concert with routine prenatal care.

Characterization of the replication region of the Lactobacillus reuteri plasmid pTC82 potentially used in the construction of cloning vector

A 3.2 kb DNA fragment containing the replication region (RR) from pTC82 was cloned, sequenced, and found to contain elements typical of plasmids that replicate via a rolling-circle mechanism of replication (RCR), including double-strand origin (DSO), replication protein gene (rep), and single-strand origin (SSO). The DSO of pTC82 contains two domains showing 55.5% and 84.6% similarities in nucleotide (nt) sequence to the conserved functional elements bind and nic, respectively, which are required for the initiation of the leading strand typical of the pC194-RCR family. Although the predicted rep gene product of pTC82 (Rep82) shares little identity (less than 24%) with other known Reps, a region containing three motifs, characteristic of the pC194-family Reps, was identified, indicating the Rep82 as a novel Rep protein of this family. Downstream of the rep82 gene, strong similarity to the typical palT type-SSO could be detected. This is the first palT type-SSO to be identified from Lactobacillus. Through a series of deletion studies, the minimal replicon of the cloned RR was found to be 2.66 kb in size including the DSO region and rep gene. This RR was further identified as being highly stable in L. reuteri and also bearing a very narrow host-range property, suggesting it to be a good replicon potentially useful in vector construction for developing L. reuteri as a vaccine carrier.

A novel consecutive chain transfer reaction to p-methylstyrene and hydrogen during metallocene-mediated olefin polymerization

This paper describes the first example of consecutive chain transfer reaction, first to p-methylstyrene (or styrene) and then to hydrogen, during metallocene-catalyzed propylene polymerization by rac-Me(2)Si[2-Me-4-Ph(Ind)](2)ZrCl(2)/MAO complex. The PP molecular weight is inversely proportional to the molar ratio of [p-methylstyrene]/[propylene] and [styrene]/[propylene] with the chain transfer constants of k(tr)/k(p) = 1/6.36 and 1/7.5, respectively. Although hydrogen does not influence the polymer molecular weight, it greatly affects the catalyst activity. Each PP chain formed contains a terminal p-methylstyrene (or styrene) unit. The terminal p-MS unit can be metalated to form a stable polymeric anion for living anionic polymerization to prepare new PP diblock copolymers, such as PP-b-PS, which are very difficult to prepare by other methods. The overall process resembles a transformation reaction from metallocene to living anionic polymerization.

Hepatoprotective effects of Arctium lappa on carbon tetrachloride- and acetaminophen-induced liver damage

The root of Arctium lappa Linne (A. lappa) (Compositae), a perennial herb, has been cultivated for a long time as a popular vegetable. In order to investigate the hepatoprotective effects of A. lappa, male ICR mice were injected with carbon tetrachloride (CCl4, 32 microl/kg, i.p.) or acetaminophen (600 mg/kg, i.p.). A. lappa suppressed the SGOT and SGPT elevations induced by CCl4 or acetaminophen in a dose-dependent manner and alleviated the severity of liver damage based on histopathological observations. In an attempt to elucidate the possible mechanism(s) of this hepatoprotective effect, glutathione (GSH), cytochrome P-450 (P-450) and malondialdehyde (MDA) contents were studied. A. lappa reversed the decrease in GSH and P-450 induced by CCl4 and acetaminophen. It was also found that A. lappa decreased the malondialdehyde (MDA) content in CCl4 or acetaminophen-intoxicated mice. From these results, it was suggested that A. lappa could protect the liver cells from CCl4 or acetaminophen-induced liver damages, perhaps by its antioxidative effect on hepatocytes, hence eliminating the deleterious effects of toxic metabolites from CCl4 or acetaminophen.

Red blood cell osmotic fragility in chronically hemodialyzed patients

Chronic renal failure induces anemia and a short erythrocyte life span. Red blood cell (RBC) osmotic fragility is the resistance of RBC hemolysis to osmotic changes that is used to evaluate RBC friability. To find the cause of shortened red cell survival in uremic patients, we evaluated the RBC osmotic fragility in 57 chronic hemodialyzed patients. Each patient had received 12 h of dialysis per week continuously prior to being enrolled in the study. Nineteen healthy volunteers served as a control group. Biochemistry, hemoglobin, electrolyte, osmolarity, beta2-microglobulin, and intact parathyroid hormone were examined before and after the dialysis session. To evaluate the osmotic fragility of RBC, blood samples were collected in heparinized test tubes. Fifty microliters of the RBC of each individual was then incubated in solutions containing a series of various concentrations of NaCl ranging from 0 to 0.6%. The concentration of NaCl at which 50% of RBCs were lysed was considered the median osmotic fragility (MOF). The results showed that the MOF was significantly greater in hemodialyzed patients before dialysis than in the control group (0.41 +/- 0.03 vs. 0.39 +/- 0.02%). The osmotic resistance to hemolysis was also recorded after dialysis (MOF 0.38 +/- 0.03%). Correlation analysis showed that the MOF was significantly correlated with urea nitrogen, serum osmolarity, and intact parathyroid hormone level. In addition, the osmotic fragility was higher in patients who had a predialysis intact parathyroid hormone level > 100 pg/dl. In conclusion, hemodialysis can improve the osmotic fragility. The mechanism underlying this improvement may be the removal of low molecular weight uremic toxins, resulting in normalization of serum osmolarity. Our results indicate that parathyroid hormone is probably a major factor influencing RBC osmotic fragility in chronic renal failure.

The hepatoprotective effects of Solanum alatum Moench. on acetaminophen-induced hepatotoxicity in mice

Solanum alatum Moench. has been shown to have a protective effect against carbon tetrachloride (CCl4)-induced liver injury. Solanum alatum treatment (100 mg/kg, p.o.) decreased the elevation of serum alanine aminotransferase (ALT; GPT) and aspartate aminotransferase (AST; GOT) induced by acetaminophen (paracetamol) (600 mg/kg, i.p.) administration. It also decreased the extent of visible necrosis in liver tissue. In addition, Solanum alatum treatment restored hepatic glutathione (GSH) depletion induced by acetaminophen (600 mg/kg, i.p.) administration. Microsomal enzyme levels such as P-450, reductase, and aniline hydroxylation enzyme were also restored to normal levels after Solanum alatum administration. The hepatoprotective mechanism may function through direct binding with acetaminophen toxic metabolites, decreasing the attraction of acetaminophen metabolites for other cellular GSH or thiol protein. Additionally, Solanum alatum treatment increased the concentration of hepatic GSH and maintained a high level activity of GSTase, which led to acceleration of the excretion of toxic acetaminophen metabolites.

Resection and permanent I-125 brachytherapy without whole brain irradiation for solitary brain metastasis from non-small cell lung carcinoma

We assessed a treatment plan of local therapy (resection and placement of permanent low dose-rate I-125 seeds) without whole brain irradiation in 15 patients with solitary brain metastasis (SBM) from primary non-small cell lung cancer between January, 1991 and May, 1996. Thirteen lesions were confirmed as solitary by MRI scan, and 2 patients had CT scan only. With median follow up of 14 months, 3 patients remain alive at 6, 33, and 62 months post-resection. Median survival is 14 months for all patients and 26 months for patients with SBM as the only site of disease. Five tumors failed in the brain: 2 solitary recurrences adjacent to the site of SBM, 2 multiple metastases outside the primary site, and 1 multiple recurrence including the primary site. No failures were seen with SBM <2.5 cm. Only 2 of 13 patients with SBM confirmed with MRI experienced relapses elsewhere in the brain. Recurrence rates both adjacent and outside the area of the initial brain lesion are similar to studies employing resection plus whole brain irradiation (WBI), and the patient is spared the acute and potential late toxicity of WBI. This approach may be considered for selected patients with solitary brain metastases (SBMs), although further experience with larger patient numbers is needed.

Cloning of erythromycin-resistance determinants and replication origins from indigenous plasmids of Lactobacillus reuteri for potential use in construction of cloning vectors

Lactobacillus reuteri L1 and N16 strains contain a 7.0-kb plasmid (pTE80) and a 15-kb plasmid (pTE15), respectively, encoding resistance to erythromycin (Em(r)). Physical maps of both plasmids were established. Nucleotide sequences of the genetic determinants encoding Em(r) on pTE80 and pTE15 revealed the existence of a very similar (ca. 99% nucleotide sequence and ca. 98% amino acid sequence identity) open reading frame for an Em(r) transmethylase gene (erm) in both plasmids. These structural erm genes, 753 and 750 bp in length, respectively, were highly related (ca. 98% nucleotide sequence and ca. 97% amino acid sequence identity) to the erm gene of L. fermentum plasmid pLEM3. Sequence analysis showed that these two erm genes from pTE80 and pTE15 could be categorized under the ermB (ermAM) class. These are the first members of the ermB (ermAM) class of Em(r) determinant from L. reuteri to be characterized at the nucleotide sequence level. The Em(r) gene from pTE80 (erm80) was then ligated into pUC18/19 to construct replication origin (RO)-screening vectors pUE80(+) and pUE80(-) (pUE80(+/-)). These plasmids contain the pUC18/19-derived multiple cloning site, ampicillin-resistance trait, and the LacZ' gene, which enable direct screening for recombinants in Escherichia coli. Once the recombinant contains a RO from L. reuteri, the Em(r) trait of erm80 is used as a selection marker for the replication of the chimeric plasmid as it is transformed into L. reuteri using the cloned RO as a replicon. Replication regions from pTE80 and pTE15 were successfully cloned into the constructed vector pUE80(-). The RO cloned from pTE80 was further identified as being highly stable in L. reuteri and also bearing a relatively narrow host range compared with that of pTE15. The Em(r) determinant (erm80) and RO cloned from pTE80 could be used in the future construction of derivatives of cloning vectors for this microbe. Moreover, the pUE80(+/-) and pTE80-RO constructed in this study have the potential to be developed as a suicide vector and an E. coli-L. reuteri shuttle vector, respectively.

The correlates of depressed mood in adolescents in Hong Kong

PURPOSE

Most studies of depressed mood and its correlates in adolescents have been conducted in Western countries. This study examined the relationship between a broad range of stressors and depressed mood in a community sample of Hong Kong adolescents.

METHODS

Secondary school students (n = 996) completed the Chinese Beck Depression Inventory (C-BDI), provided demographic information, and indicated their perceptions of family and peer relationships, school function and pressures, and subjective health, and some measures salient to the Hong Kong environment: triad gang pressure, religiosity, and intent to emigrate. The correlation between C-BDI and these variables was assessed in bivariate and multivariate analyses.

RESULTS

Hong Kong adolescents reported higher levels of depressive symptoms than a comparison group of Western teenagers. Girls showed more symptoms than boys. All stressors correlated in bivariate analyses with C-BDI, indicating similar influences on depressed mood in Western and Hong Kong teenagers. In multivariate analyses, the stressors contributed cumulatively to the C-BDI score. Perceptions of a lack of parental understanding and peer acceptance appeared as the strongest variables in predicting depressed mood.

CONCLUSIONS

Depressed mood is highly prevalent among Hong Kong teenagers. Stressors play a cumulative role in their relationship to mood. Our findings point to the importance of broad screening of this vulnerable population.

Molecular characterization of a plasmid-borne (pTC82) chloramphenicol resistance determinant (cat-TC) from Lactobacillus reuteri G4

Lactobacillus reuteri G4 contains a 7.0-kb plasmid (pTC82) encoding resistance to chloramphenicol (Cm). Determination of the nucleotide sequence of the genetic determinant (cat-TC) encoding resistance to Cm on pTC82 revealed an open reading frame for a 238-amino-acid Cm acetyltransferase (CAT) monomer. This structural cat gene, 714 bp in length, was highly related (ca. 95% nucleotide and ca. 81% amino acid identity) to the 648-bp cat gene from Staphylococcus aureus plasmid pC194. A total of 6 bp transversions and 4 bp deletions was observed along the whole DNA sequence of cat-TC compared to that of cat-pC194. To determine the activity of the putative cat-TC gene, recombinant plasmid pUC8217 containing the cat determinant from pTC82 was subjected to a maxicell analysis. The observed molecular mass of the synthesized protein, based on electrophoretic mobility, was in reasonable agreement with the 27.3 kDa predicted from the DNA sequence. This is the first reported nucleotide sequence of a Cm-resistance determinant from L. reuteri and also the first evidence of adding Lactobacillus to the list of versatile bacterial genera which naturally acquire the cat-pC194 gene in the microbial ecological system.

[A survey on sex knowledge and medical demand of the cases in Kaohsiung city adolescent health clinic]

The purpose of this survey is to study the sex knowledge of adolescents, and to analyze their need in sex consultation and related health problem in Kaohsiung city. A total of 1,000 study subjects were recruited from May 1991 to May 1994. A self-administered questionnaire and medical records were used to obtain related information. The results were as follows: 1. The male to female ratio of study subjects was 1:2. Half of them were students, 44.1% had sexual experience, and the mean +/- standard deviation of age at first sex experience was 19.1 +/- 2.8 years. 2. The average percentage of correct knowledge was as low as 67.6%. It indicated an inadequacy of sex knowledge in adolescents. Females had better knowledge than males. Subjects who had graduated from senior high schools had better knowledge than those graduated from middle schools. No association was found between the score of sex knowledge and occupation. 3. 12.5% of study subjects believed that "masturbation" might cause neurasthenia, kidney malfunction and loss of memory, while 11.9% recognized that "nocturnal emission" might result in abnormal ejaculation, mental aberration and guilty feelings. Furthermore, 3.8% considered that kissing, hugging or sleeping together might cause pregnancy. 4. Most adolescents felt that "guidance on sex knowledge" was the major reason for them to visit the adolescent clinic and "obstetric and gynecological problems" was the second most important. 5. Males and females have the same prevalence of sex experience, and 50.6% of them did not practice contraception. 88.9% subjects had a high risk of getting pregnancy. 6. Males had a higher percentage of more than one heterosexual partner than females did. There was a higher percentage of people with a high education level having a fixed heterosexual partner than that of those with a low education level.

Production and isolation of reuterin, a growth inhibitor produced by Lactobacillus reuteri

Lactobacillus reuteri is a prominent member of the Lactobacillus population in the gastrointestinal ecosystem of humans, poultry, swine, and other animals. Reuterin is a newly discovered, broad-spectrum antimicrobial substance produced by this species during fermentation of glycerol. In this report, we describe procedures for (i) producing reuterin in sufficient amounts to isolate from a fermentation mixture and (ii) isolating this substance by high-performance liquid chromatography. By using uniformly labeled [14C]glycerol, reuterin was identified as a product of glycerol fermentation associated with the production of beta-hydroxypropionic acid and trimethylene glycol.