A physical mechanism underlying the torque generation of the bacterial flagellar motor

This study proposes a physical mechanism underlying the torque generation of a bacterial flagellar motor (BFM), in which the torque for the rotation of the rotor can be generated from impulsive forces resulting from collisions between the randomly moving stator and rotor. The torque required for the rotation of the rotor may be generated through two coexisting mechanisms: mechanism (A), in which the stator collides with the rotor, whose rotation axis fluctuates asymmetrically, generating a torque in the direction of the rod, and mechanism (B), in which physical collisions between the stator and the asymmetric [Formula: see text]and [Formula: see text] generate the torque in the direction of the rod. Mechanism (A) might be related the bidirectional rotation and the tumbling of the motion of the cell. Mechanism (B) might be related to occurrence of the steps in the time traces of the rotational angle, backward stepping or switching of the rotational direction, and the knee-shaped [Formula: see text]-[Formula: see text] relation. The above-mentioned characteristics of the rotation of BFM are reproduced in a model device designed to confirm the applicability of the proposed concept to real BFM. Moreover, a prediction of the disappearance of the knee-shaped [Formula: see text]-[Formula: see text] relation of the actual BFM at a high temperature is proposed.

Nanotwin orientation on history-dependent stress decay in Cu nanopillar under constant strain

Cu with nanotwin (NT) possesses great electrical, mechanical, and thermal properties and has potential for electronic applications. Various studies have reported the effect of NT orientation on Cu mechanical properties. However, its effect on Cu stress-relaxation behavior has not been clarified, particularly in nano-scale. In this study, Cu nanopillars with various orientations were examined by a picoindenter under constant strain and observed byin situTEM. The angles between the twin plane and the loading direction in the examined nanopillars were 0°, 60°, to 90°, and a benchmark pillar of single-crystal Cu without NT was examined. The stress drops were respectively 10%, 80%, 4%, and 50%. Owing to the interaction by NT, the dislocation behavior in nanopillars was different from that in bulk or in thin film samples. Especially, the rapid slip path of dislocations to go to the free surface of the nanopillar induced a dislocation-free zone in the 0° nanopillar, which led to work-softening. On the contrary, a high dislocation density was observed in the 90° nanopillar, which was generated by dislocation interaction and obstruction of dislocation slip by twin planes, and it led to work-hardening. The findings reveal the NT orientation in Cu nanopillars affected stress relaxation significantly.

Impact of the COVID-19 pandemic on emergency healthcare utilization: a cohort study

Background

Emergency department (ED) crowding is a burden on public health, so understanding the characteristics of frequent ED users is a key concern of the healthcare system and policy makers. This study aims to examine the characteristics and healthcare-seeking behaviors in frequent ED users before and during the COVID-19 pandemic.

Methods

A retrospective observational study was conducted on ED users aged 18 years and over admitted to Taipei City Hospital in February 2019-January2020 (before pandemic) and February 2020-January2021 (during pandemic) (N = 120,011). Frequent and ED users were defined as patients with four or more ED visits in a year. Multivariate logistic regression was used to identify the predictors of frequent ED use before and during the COVID-19 pandemic.

Results

Monthly emergency department visits were significantly lower during the pandemic (by 10.1-26.8%). Frequent ED patients had shorter lengths of stay in the ED during the pandemic (212.5 vs.233.9 minutes; P < 0.0001). The proportion of ED patients receiving chest CT examination during the pandemic has increased by 0.5-0.6%. After adjusting for sociodemographic factors, triage status, mode of arrival, and copayment exemption, patients with a triage status of level 4-5 (AOR=1.60, 95% CI: 1.13-2.28), diagnosis of pneumonia (AOR=1.85, 95% CI: 1.07-3.17), giddiness (AOR=2.85, 95% CI: 1.82-4.45), dyspnea (AOR=1.85, 95% CI: 1.00-3.39), or chronic kidney disease (AOR=5.05, 95% CI: 2.66-9.59) were more likely to be frequent ED visitors during the pandemic.

Conclusions

Since SAR-CoV-2 is highly contagious, it is imperative to educate non-emergent patients to utilize outpatient medical services rather than emergency medical services to reduce the risk of COVID-19 outbreaks at the ED.

Key messages

This study found that the utilization of emergent medical services during the COVID-19 pandemic significantly decreased by 10.1%–26.8% compared to before the COVID-19 pandemic. The lengths of stay in frequent ED users during the COVID-19 pandemic were significantly shorter than that in frequent ED users before the COVID-19 pandemic.

Mask reuse during the COVID-19 pandemic: a national survey in Taiwan

Background

The use of masks is an effective measure to prevent severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection; however, mask reuse is not recommended. Studies examining the factors associated with mask reuse during the coronavirus disease (COVID-19) pandemic are limited. This nationwide survey aimed to determine the prevalence and factors associated with mask reuse among Taiwanese citizens during the pandemic.

Methods

From May 18 through May 31, 2020, a computer-assisted telephone interview system was used to randomly select Taiwanese citizens who were interviewed for COVID-19 preventive behaviors and knowledge on the usage of masks. Multivariate logistic regression was used to identify factors associated with mask reuse during the COVID-19 pandemic. Moreover, generalized estimating equations (GEE) were used to analyze the rate of mask reuse among participants before and during the pandemic.

Results

For a total of 1,075 participants, the overall mean age was 57.4 years, and 82.2% of participants reported mask reuse during the COVID-19 pandemic. After controlling for other covariates, participants who had a greater knowledge on mask usage or had a high supply of masks were less likely to reuse masks during the pandemic. GEE analysis showed that compared with the participants' mask wearing behaviors before the COVID-19 pandemic, they were more likely to reuse masks during the pandemic.

Conclusions

The rate of mask reuse among the general population during the pandemic was significantly higher than that before the pandemic. Individuals were less likely to reuse masks if they had adequate knowledge on mask usage or had a high supply of masks. Since mask reuse is associated with a higher risk of COVID-19 due to the possibility of wearing SAS-CoV-2-contaminated masks, it is imperative to educate people on the correct usage of masks. Further, the government should provide sufficient masks to the general population to decrease the reuse of masks.

Key messages

Mask reuse increased during the COVID-19 pandemic due to the shortage in supply. It is imperative to educate people about the correct usage of masks.

Performance and reading time of lung nodule identification on multidetector CT with or without an artificial intelligence-powered computer-aided detection system

AIM

To compare the performance and reading time of different readers using automatic artificial intelligence (AI)-powered computer-aided detection (CAD) to detect lung nodules in different reading modes.

MATERIALS AND METHODS

One hundred and fifty multidetector computed tomography (CT) datasets containing 340 nodules ≤10 mm in diameter were collected retrospectively. A CAD with vessel-suppressed function was used to interpret the images. Three junior and three senior readers were assigned to read (1) CT images without CAD, (2) second-read using CAD in which CAD was applied only after initial unassisted assessment, and (3) a concurrent read with CAD in which CAD was applied at the start of assessment. Diagnostic performances and reading times were compared using analysis of variance.

RESULTS

For all readers, the mean sensitivity improved from 64% (95% confidence interval [CI]: 62%, 66%) for the without-CAD mode to 82% (95% CI: 80%, 84%) for the second-reading mode and to 80% (95% CI: 79%, 82%) for the concurrent-reading mode (p<0.001). There was no significant difference between the two modes in terms of the mean sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) for both junior and senior readers and all readers (p>0.05). The reading time of all readers was significantly shorter for the concurrent-reading mode (124 ± 25 seconds) compared to without CAD (156 ± 34 seconds; p<0.001) and the second-reading mode (197 ± 46 seconds; p<0.001).

CONCLUSION

In CAD for lung nodules at CT, the second-reading mode and concurrent-reading mode may improve detection performance for all readers in both screening and clinical routine practice. Concurrent use of CAD is more efficient for both junior and senior readers.

Mechanical mechanism for the translocation of hexameric and nonstructural helicases: Dependence on physical parameters

Three recently observed facts of the translocation of actual hexameric and nonstructural (NS) helicases are related to the various physical quantities and are in accordance with the recently proposed mechanical mechanism: a) the translocation of hexameric helicases might be led by either the N-terminal domain (NTD) or C-terminal domain (CTD) depending on which domain has a smaller central pore, b) the translocation speed (v_t) of the ring-shaped helicases and NS helicases decreased with decreasing applied tension, and c) a large difference in the v_t of the NS helicase was observed for the helicase translocating on DNA and RNA. These findings are the effects of the physical quantities of the helicase/nuclei acid strands on the translocation of helicases and are difficult to explain with biochemical models. We predict that a similar behavior as described in b) and c) is also shown by hexameric helicases. The validity of the mechanical mechanism is demonstrated in simulation experiments.

Helicobacter pylori infection and the risk of colorectal cancer: a nationwide population-based cohort study

BACKGROUND

The role of Helicobacter pylori (H. pylori) infection in the development of colorectal neoplasia has been a matter of scientific debate with controversial findings.

AIMS

This study examined the association between H. pylori infection and colorectal cancer (CRC) in a nationwide population-based Chinese cohort study.

METHODS

A total of approximately 3936 individuals with newly diagnosed H. pylori infection (the H. pylori-infected cohort) and 15 744 age- and sex-matched patients with diagnoses absence of H. pylori infection (the comparison cohort) from 2000 to 2005 were identified from Taiwan's National Health Insurance Research Database. The Kaplan-Meier method was used for measuring the cumulative incidence of CRC in each cohort. Cox proportional hazards models were used to compute hazard ratios (HRs) and accompanying 95% confidence intervals (CIs) for the estimation of the association between H. pylori infection and CRC.

RESULTS

The cumulative incidence of CRC was higher in H. pylori-infected cohort than that in the comparison cohort (log-rank test, P < 0.001). After adjustment for potential confounders, H. pylori infection was associated with a significantly increased risk of CRC (adjusted HR 1.87; 95% CI 1.37-2.57). In addition, the HR of CRC appeared to increase with increasing frequency of clinical visits for H. pylori infection.

CONCLUSIONS

Our study demonstrated that H. pylori infection was associated with an increased risk of CRC, which warrants confirmation and exploration of the underlying biologic mechanisms by future studies.

'Transformed rights' sexual health programme evaluation for the parents and service workers of adults with an intellectual disability

BACKGROUND

To promote sexual health in adults with an intellectual disability (ID) in Taiwan, sexual health programmes were provided to adults with ID, their parents and service workers. This study evaluates the impact of these programmes that involved the parents and service workers.

METHODS

Intervention and participatory research paradigms were applied to develop, implement and evaluate programmes that address the challenges that relate to the sexual rights of adults with ID. Additionally, the programmes fostered open dialogue among the participants concerning the sexual health of people with ID. In total, 57 parents and 164 service workers were involved in the programmes. A quasi-experimental design and standardised questionnaires (Attitudes to Sexuality Questionnaire - Individuals with an Intellectual Disability), as well as in-depth interviews, were used to collect both quantitative and qualitative data on the programmes' effectiveness and participants' experiences between April 2012 and July 2015.

RESULTS

The findings revealed that after the programmes were implemented, attitudes towards the sexual rights of people with ID were significantly more positive among both the parents and service workers. Participation in the sexual health programmes facilitated constructive dialogue by revealing hidden concerns and by transforming the perspectives of the parents and service workers from viewing sexuality as a social problem to understanding the sexual rights of adults with ID.

CONCLUSIONS

Both the quantitative and qualitative results demonstrate that the programmes had a positive impact on the parents and service workers in terms of their attitudes towards the sexual rights of people with ID. Open dialogue and reciprocal interaction strategies caused transformations in the perspectives of parents and service workers on sexual health.

Observations of metastable states of the free swelling knots and directional motion of tensioned knots in vibrated bead chains

The free swelling of knots and the directional motion of knots under tension were studied in vertically vibrated bead chains. A metastable state of swelling was observed in the strongly vibrated two-end-free bead chains, as predicted by Grosberg and Rabin (Phys. Rev. Lett. 99, 217801 (2007)). Knots in the two-end-fixed chains were found to move directionally. The direction of motion could be changed by flipping the knot over. The velocity of motion depended on the tension in the bead chain. The effects of tension on the motion of knots were studied in one-end-fixed chains. The directional reptation might have been influenced by the random motion of the leading arc of the knot. The knots might move in a forced-reptation manner under the interaction with a simulated translocase.

Stroke in Parkinson's disease

BACKGROUND

The association between Parkinson's disease (PD) and stroke remains completely understood.

AIM

We aimed to investigate stroke risk and post-stroke outcomes in patients with PD.

DESIGN

The retrospective cohort study included 1303 patients aged ≥ 40 years with new-diagnosed PD and 5212 non-PD adults were selected by frequency matching with age and sex in 2000-05. Both two groups were followed up until the end of 2013. Another nested stroke cohort study of 17 678 patients with stroke hospitalization in 2002-09 was conducted to compare the admission outcome in patients with and without PD history.

METHODS

We collected patients' characteristics and medical conditions in the present two studies from claims data of Taiwan's National Health Insurance. Incidences and risks of stroke in people with and without PD during the follow-up period were calculated by adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) in the Cox proportional hazard model. Complications and mortality during the stroke admission associated with PD were analysed by calculating adjusted odds ratios (ORs) and 95% CIs in the logistic regressions.

RESULTS

Incidences of stroke for people with and without PD were 19.8 and 9.93 per 1000 person-years, respectively, with corresponding HR of 1.96 (95% CI 1.67-2.30). History of PD was associated with post-stroke gastrointestinal bleeding (OR 1.25, 95% CI 1.05-1.49), epilepsy (OR 1.64, 95% CI 1.32-2.04), pneumonia (OR 1.34, 95% CI 1.20-1.49), urinary tract infection (OR 1.33, 95% CI 1.21-1.45) and mortality (OR 1.35, 95% CI 1.13-1.62).

CONCLUSION

PD increases stroke risk and influences post-stroke outcomes.

Overexpression of AdeABC efflux pump associated with tigecycline resistance in clinical Acinetobacter nosocomialis isolates

OBJECTIVES

Tigecycline non-susceptible Acinetobacter nosocomialis (TNAN) has been discovered in clinical isolates. The resistance-nodulation-cell division (RND)-type efflux system plays a major role in tigecycline non-susceptible Acinetobacter baumannii, but the mechanism in A. nosocomialis remains unknown. Our aim was to analyse the contribution of efflux-based tigecycline resistance in clinical A. nosocomialis isolates collected from multiple medical centres in Taiwan.

METHODS

A total of 57 A. nosocomialis isolates, including 46 TNAN and 11 tigecycline-susceptible A. nosocomialis (TSAN) isolates, were analysed. Of these, 46 TNAN isolates were clustered to ST410 (43 isolates) and ST68 (three isolates) by multi-locus sequence typing.

RESULTS

The relationship between the RND efflux pump and tigecycline resistance was indirectly verified by successfully reducing tigecycline resistance with NMP, an efflux pump inhibitor. The three RND efflux systems (AdeABC, AdeIJK and AdeFGH) were detected in all clinical isolates. The transcript level of adeB gene increased significantly and was correlated with tigecycline resistance. Moreover, the AdeRS two-component system was further classified into four different types of AdeRS patterns considering the amino acid sequence. Further analysis showed that tigecycline resistance was related to the transcript level of adeB gene and the AdeRS pattern.

CONCLUSION

This study showed that the dissemination of TNAN isolates in Taiwan is attributable mainly to the spread of ST410. The AdeABC efflux pump appeared to play an important role in the tigecycline resistance of A. nosocomialis.

Comparison of self-determination of students with disabilities: multivariate and discriminant function analyses

BACKGROUND

Self-determined behaviour is composed of multiple, interrelated component elements, and yet little empirical study has researched the self-determination components other than choice making and goal setting. Also, few theoretical relationships have been drawn between the component elements of self-determined behaviour and the impact of disability category. Therefore, this study examined profiles of the combination of three self-report measures of component elements of self-determined behaviour (autonomous functioning, problem solving and internal locus of control) between two groups (ID and learning disabilities/emotional disorders).

METHOD

We analysed data from 96 middle school and high school students ages 13 through 22 years who completed three self-report instruments of the Autonomy - section 1 of The Arc's Self-determination Scale, the Problem Solving Survey and the Nowicki-Strickland Locus of Control Scale. A multivariate analysis of covariance was conducted to investigate the differences between the two groups after controlling for the developmental effects of age. A discriminant function analysis examined whether membership of the two groups could be predicted from the three component elements.

RESULTS

Results showed that each group had different profiles within the combined three component elements of self-determination but groups were not different on any single measure of component elements of self-determined behaviour exclusively. The combination of three variables was useful in confirming the membership of two dichotomous groups.

CONCLUSIONS

Score differences on the three component behaviour imply that the two groups have different instructional needs and therefore require differentiated instructional approaches. The three measures of the component elements of self-determined behaviour collectively separate the two groups, suggesting that the component elements should be considered in a combination as opposed to being treated as individual elements in the context of discussing self-determined behaviour.

Torque generation through the random movement of an asymmetric rotor: A potential rotational mechanism of the γ subunit of F(1)-ATPase

The rotation of the γ subunit of F(1)-ATPase is stochastic, processive, unidirectional, reversible through an external torque, and stepwise with a slow rotation. We propose a mechanism that can explain these properties of the rotary molecular motor, and that can determine the direction of rotation. The asymmetric structures of the γ subunit, both at the tip of the shaft (C and N termini) and at the part (ε subunit) protruding from the α(3)β(3) subunits, are critical. The torque required for stochastic rotation is generated from the impulsive reactive force due to the random collisions between the γ subunit and the quasihexagonal α(3)β(3) subunits. The rotation is the result of the random motion of the confined asymmetric γ subunit. The steps originate from the chemical reactions of the γ subunit and physical interaction between the γ subunit and the flexible protrusions of the α(3)β(3) subunits. An external torque as well as a configurational modification in the γ subunit (the central rotor) can reverse the rotational direction. We demonstrate the applicability of the mechanism to a macroscopic simulation system, which has the essential ingredients of the F(1)-ATPase structure, by reproducing the dynamic properties of the rotation.

Risk and adverse outcomes of fractures in patients with Parkinson's disease: two nationwide studies

The association between Parkinson's disease and fracture was not completely understood. This nationwide study investigated increased risk of fracture in patients with Parkinson's disease. In the nested cohort study, Parkinson's disease was associated with pneumonia, septicemia, stroke, urinary tract infection, and mortality after fracture admission.

INTRODUCTION

Falls are a common complication in people with Parkinson's disease (PD). This study evaluated fracture risk and post-fracture outcomes in patients with PD.

METHODS

We identified 1,423 adults aged 40 years and older newly diagnosed with PD using the Taiwan National Health Insurance Research Database from 2000 to 2003. Comparison cohort consisted of 5,692 adults without PD randomly selected from the same dataset, frequency matched in age and sex. Followed-up events of fracture from January 1, 2000, until December 31, 2008, were ascertained from medical claims. Adjusted hazard ratios (HR) and 95 % confidence interval (CI) of fracture associated with PD were evaluated. Another nested cohort study of 397,766 hospitalized fracture patients analyzed for adjusted odds ratios (ORs) and 95 % CIs of adverse events after fracture among patients with and without PD between 2004 and 2010.

RESULTS

The incidences of fracture for people with and without PD were 39.5 and 23.9 per 1,000 person-years, respectively (p < 0.0001). Compared with control, the adjusted HR of fracture was 2.25 (95 % CI 1.97-2.58) for PD patients. Previous PD was associated with risks of pneumonia (OR 1.44, 95 % CI 1.36-1.52), septicemia (OR 1.41, 95 % CI 1.33-1.49), stroke (OR 1.40, 95 % CI 1.32-1.50), urinary tract infection (OR 1.53, 95 % CI 1.46-1.61), and mortality (OR 1.25, 95 % CI 1.15-1.35) after fracture.

CONCLUSIONS

PD was associated with higher risk of fracture. Patients with PD had more complications and mortality after fracture. Fracture prevention and attention to post-fracture adverse events are needed for this susceptible population.

The recommended dose of ertapenem poses a potential risk for central nervous system toxicity in haemodialysis patients - case reports and literature reviews

WHAT IS KNOWN AND OBJECTIVE

Dosage adjustment of 500 mg ertapenem daily is recommended for patients with advanced kidney disease. 30% of ertapenem is cleared by a session of haemodialysis (HD). However, because most published carbapenems studies have excluded patients on dialysis, little is known about the dosing of ertapenem to avoid central nervous system (CNS) toxicity in regular HD patients. We report of four patients who developed CNS toxicity in such patients.

CASE SUMMARY

The 4 HD patients developed unexplained CNS toxicity manifested as seizures, hallucination and cognitive dysfunction after receiving 3-7 consecutive recommended doses of ertapenem. Their symptoms of CNS toxicity were completely resolved within 8 days after discontinuation of ertapenem. In one of our presented cases, we demonstrated the very high level of plasma ertapenem accumulating with several consecutive doses. Cognitive function gradually recovered in line with a corresponding decline in blood level of ertapenem.

WHAT IS NEW AND CONCLUSIONS

This is the first report of ertapenem-associated CNS toxicity in patients on regular HD and utilizing the plasma ertapenem concentration to demonstrate the causal relationship. The recommended dosage of 500 mg ertapenem daily may be still too high in regular HD patients, especially in Asians, owing to their relatively small body size. An increased awareness of ertapenem-associated CNS toxicity would avoid unnecessary examinations, hospitalization, and potentially catastrophic complications.

Impact of metabolic syndrome components on incident stroke subtypes: a Chinese cohort study

Limited evidence is available on the risk differences in the development of stroke subtypes in relation to particular clustering patterns of the metabolic syndrome (MetS) components. A follow-up study of a Chinese cohort involving 10,292 individuals was performed to assess the roles of cluster patterns of the MetS components in the prediction of incident stroke subtypes. During follow-up, there were 161 incident cases of ischemic strokes and 41 incident cases of hemorrhagic strokes. Among MetS components, only the hypertensive trait was associated with significantly elevated risks of both ischemic and hemorrhagic strokes. Furthermore, MetS with hypertension as components was associated with increased risk of ischemic and hemorrhagic strokes (adjusted hazards ratio (95% confidence interval) was 2.96 (1.94-4.50) and 2.93 (1.25-6.90), respectively) as compared with those who had neither hypertension nor MetS. Notably, as the number of the MetS components increased, the risk of ischemic stroke significantly and dose-dependently increased. This implies a cumulative effect of MetS components in elevating the risk of ischemic stroke. These findings suggest that MetS comprises heterogenous clusters with respect to the risk of developing the subtype of stroke.

Entropic force on granular chains self-extracting from one-dimensional confinement

The entropic forces on the self-retracting granular chains, which are confined in channels with different widths, are determined. The time dependence of the length of chain remaining in the channel Lin(t) is measured. The entropic force is treated as the only parameter in fitting the solution of the nonlinear equation of motion of Lin(t) to the experimental data. The dependence of the entropic force on the width of the confining channel can be expressed as a power-law with an exponent of 1.3, which is consistent with the previous theoretical predictions for the entropy loss due to confinement.

Force generation by granular chains moving randomly on periodic ratchet plates

A variation of the Brownian ratchet mechanism for the force generated by the combination of the random motion and the ratchet structure is proposed and simulated with granular chains moving randomly on periodic ratchet plates. The present mechanism differs from the flashing ratchet model of the kinesin-microtubule molecular motor. When the bead chain bounces against the periodic ratchet, the chain as a whole will gain an impulse in the direction of the long side (the side with smaller slope). The observed behaviors of the simulating system, including (i) the force-velocity relation, (ii) the stall force as a function of the number of chains, (iii) the increase of velocity with the excitation, and (iv) the appearance of steps at low velocity and its distribution function, are similar to the corresponding ones of the kinesin-microtubule system.

Gate effects on DNA translocation through silicon dioxide nanopore

The effects of gate voltage on the translocation of DNA molecules through a nanopore are studied. A twenty-fold increase in the translocation time is observed with a positive gate voltage applied, without changing too much of the ionic current. The amplitude of the current blockage by the DNA molecules was reduced by roughly the same factor. At the same time, the number of the blocking events decreases significantly. The applied gate voltage also modulates the scatter plot of the amplitude of the current blockage against the dwell time. The observations are consistent with the recent theoretical results.

Collapse kinetics of vibrated granular chains

The kinetics of the collapse of the coil state into condensed states is studied with vibrated granular chain composed of N metal beads partially immersed in water. The radius of gyration of the chain, R(g) is measured. For short chains (N < 140), disk-like condensed state is formed and R(g) decreases with time such that the function ΔR(g)(2) (≡ R(g)(2) - R(g)(2)(∞)) = A e(-t/τ), where the relaxation time τ follows a power-law dependence on the chain length N with an exponent γ = 1.9 ± 0.2. For the chains with length N ≥ 300, rod-like clusters are observed during the initial stage of collapse and R(g)(2) = R(g)(2)(0) - Bt(β), with β = 0.6 ± 0.1. In the coarsening stage, the exponential dependence of ΔR(g)(2) on time still holds, however, the relaxation time τ fluctuates and has no simple dependence on N. Furthermore, the time dependence of the averaged radius of gyration of the individual clusters, R(g,cl) can be described by the theory of Lifshitz and Slyozov. A peak in the structure function of long chains is observed in the initial stage of the collapse transition. The collapse transition in the bead chains is a first order phase transition. However, features of the spinodal decomposition are also observed.

Geometrical frustration in nanowire growth

Idealized nanowire geometries assume stable sidewalls at right angles to the growth front. Here we report growth simulations that include a mix of nonorthogonal facet orientations, as for Au-catalyzed Si. We compare these with in situ microscopy observations, finding striking correspondences. In both experiments and simulations, there are distinct growth modes that accommodate the lack of right angles in different ways--one through sawtooth-textured sidewalls, the other through a growth front at an angle to the growth axis. Small changes in conditions can reversibly switch the growth between modes. The fundamental differences between these modes have important implications for control of nanowire growth.

Outcomes of a new residential scheme for adults with intellectual disabilities in Taiwan: a 2-year follow-up

BACKGROUND

The Taiwanese government launched a new programme in November 2004 to support adults with intellectual disabilities living in smaller facilities. This paper aims to evaluate the service outcomes of this new residential scheme over 2 years including those residents who moved from an institution and those who moved from their family.

METHODS

A one-group repeated-measures analysis was conducted for five interviews after the adults with intellectual disabilities entered the new environment. Forty-nine adults were initially studied (T1) and 29 adults remained in the homes until the end of the study (T5).

RESULTS

This study found significant improvements over the 2 years in the residents' quality of life and family contact. The results also highlight a decrease in maladaptive behaviour among the residents moving from institution and an increase in choice making and family contact among the residents moving from family. No significant changes in adaptive behaviour and community inclusion were found.

CONCLUSION

Results revealed that further policy changes and financial support including service quality assurance are required in order to improve service outcomes for adults living in the new residential scheme.

Initial validation of the Chinese Quality of Life Questionnaire-Intellectual Disabilities (CQOL-ID): a cultural perspective

BACKGROUND

In the field of intellectual disabilities (ID), the quality of life concept has been developing rapidly in Chinese societies including Hong Kong, mainland China and Taiwan. However, there is a lack of locally validated instruments to measure the quality of life of people with ID. The study reported in this paper attempted to validate the Chinese Quality of Life Questionnaire - Intellectual Disabilities adapted from the Quality of Life Questionnaire developed by Schalock & Keith.

METHODS

People with mild/moderate ID aged 15 years or above were recruited from special schools, skills centres, community service units and residential units in different regions of Hong Kong. A number of procedures were followed including reliability tests, factor analysis, content validity and construct validity.

RESULTS

A total of 359 participants were recruited for the study. Factor analysis was conducted according to the rotated component matrix method, in which 23 items were extracted from the original 40-item version of the Quality of Life Questionnaire and three domains (renamed satisfaction, competence and daily choice making/interpersonal relations) were observed. The items in each domain were shown to have factor loadings ranging from 0.42 to 0.90. Construct validity tests indicated the positive nature of the relationship between earnings, and that self-determination and social interaction increase with more independent living environments and less segregated work environments achieving higher scores (P<0.000, P<0.01 and P<0.05 respectively). The scale also achieved a good degree of reliability (Cronbach's α=0.79).

CONCLUSIONS

Initial validity tests indicated that the Chinese Quality of Life Questionnaire - Intellectual Disabilities may be a useful instrument for measuring the quality of life of Chinese people with ID. Cultural issues are discussed and recommendations for future research and service development are made.

Deciding about sterilisation: perspectives from women with an intellectual disability and their families in Taiwan

BACKGROUND

This qualitative study explores decision-making regarding sterilisation for women with intellectual disabilities (ID) living with their families, including how such decisions are made and who is involved in the decision-making.

METHODS

Eleven families including sterilised women with ID participated in the study. Semi-structured interviews were conducted with family members and four of the women with ID; the interviews took place at the family homes during March 2009. The interview schedule sought information regarding decision-making on sterilisation including the reasons for the sterilisation, the identities of those involved in the decision-making, attitudes towards the sexuality of women with ID and the role of women with ID in decision-making about their own sterilisation. Additionally, women with ID were asked about their experiences of sterilisation.

RESULTS

The data showed that most of the women who underwent tubal ligation were married and had mild ID; the decision to perform tubal ligation was mostly made by the husband or parents-in-law, and was made after the women had given birth. The reasons given by the families of these women for deciding on sterilisation included: the woman was unable to care for the children, the family could not afford to raise many children, the concern that the ID might be hereditary, or a perceived risk of pregnancy from rape. The two women who underwent hysterectomy were unmarried and had more severe ID than the married women with ID who received tubal ligation. In these two cases, the decisions were primarily made by the mothers of the women based on concerns about managing their menstruation. Almost none of the women with ID were involved in the decision-making process, and some were not even informed of the nature of the surgery. Health professionals and service workers contacted by the families were also influential in the decision-making. The autonomy of the women to engage in decision-making regarding sterilisation thus was constrained by their families and professionals, without considering either sterilisation or hysterectomy a violation of the essential human rights of the women involved.

CONCLUSION

The results suggest that with respect to sexuality and body images among women with ID, concern should exist among society in general and among professionals in particular, regarding human rights; furthermore, more information and better educational programmes must be provided to relevant professionals, as well as to women with ID and their families.

Depressive symptoms in older female carers of adults with intellectual disabilities

BACKGROUND

This survey study aims to examine the prevalence and factors associated with depressive symptoms among primary older female family carers of adults with intellectual disabilities (ID).

METHOD

In total, 350 female family carers aged 55 and older took part and completed the interview in their homes. The survey package contained standardised scales to assess carer self-reported depressive symptoms, social support, caregiving burden and disease and health, as well as adult and carer sociodemographic information. Multiple linear regressions were used to identify the factors associated with high depressive symptoms in carers.

RESULTS

Between 64% and 72% of these carers were classified as having high depressive symptoms. The factors associated with carer self-reported depressive symptoms were carer physical health, social support and caregiving burden; overall, the carer self-reported physical health was a stronger factor associated with depressive symptoms than their physical disease status. The level of the adult with ID's behavioural functioning and the carer age, marital status, employment status, education level and the family income level were not significantly associated with carer depressive symptoms.

CONCLUSIONS

The factors identified in this study as correlating with self-reported depressive symptoms suggest that researchers and mental health professionals should collaborate to help improve the physical health and social support networks of the most vulnerable older female family carers. This should reduce depressive symptoms directly among this high-risk group.

Growth of multiple metal/semiconductor nanoheterostructures through point and line contact reactions

Forming functional circuit components in future nanotechnology requires systematic studies of solid-state chemical reactions in the nanoscale. Here, we report efficient and unique methods, point and line contact reactions on Si nanowires, fabricating high quality and quantity of multiple nanoheterostructures of NiSi/Si and investigation of NiSi formation in nanoscale. By using the point contact reaction between several Ni nanodots and a Si nanowire carried out in situ in an ultrahigh vacuum transmission electron microscopy, multiple sections of single-crystal NiSi and Si with very sharp interfaces were produced in a Si nanowire. Owing to the supply limited point contact reaction, we propose that the nucleation and growth of the sugar cane-type NiSi grains start at the middle of the point contacts between two Ni nanodots and a Si nanowire. The reaction happens by the dissolution of Ni into the Si nanowire at the point contacts and by interstitial diffusion of Ni atoms within a Si nanowire. The growth of NiSi stops as the amount of Ni in the Ni nanodots is consumed. Additionally, without lithography, utilizing the line contact reaction between PS nanosphere-mediated Ni nanopatterns and a nanowire of Si, we have fabricated periodic multi-NiSi/Si/NiSi heterostructure nanonowires that may enhance the development of circuit elements in nanoscale electronic devices. Unlike the point contact reaction, silicide growth starts at the contact area in the line contact reaction; the different silicide formation modes resulting from point and line contact reactions are compared and analyzed. A mechanism on the basis of flux divergence is proposed for controlling the growth of the nano-multiheterostructures.

Validation of Spilornis cheela hoya TaqMan probes for potential gender identification of many Accipitridae species

The objective of this study was to test the hypothesis that genders of Accipitridae species, with the same or similar sequences to our previously proposed Spilornis cheela hoya (S. c. hoya) chromo-helicase-DNA binding protein (CHD)-W-specific and CHD-ZW-common TaqMan probes, can be successfully determined. Eight species of Accipitridae with known genders were collected. After PCR, TA cloning, sequencing, and alignment analyses, sequence length differences of Griffiths P2/P8 PCR amplicons between CHD-Z and CHD-W genes ranged from 2 to 19 bp for these Accipitridae species, and they were unsolved in 3% agarose gel. Using our previous proposed S. c. hoya TaqMan probes, the genders of Circaetus gallicus, completely homologous to the sequences for these CHD probes, were successfully identified. With one nucleotide difference to S. c. hoya CHD-W-specific probe, gender identification of Accipiter gularis, Accipiter soloensis, Accipiter trivirgatus, Accipiter virgatus, and Butastur indicus were validated. With two nucleotide differences in the CHD-W-specific probe and one nucleotide difference in the CHD-ZW-common probe, Pernis ptilorhyncus also performed well for gender identification. In conclusion, the S. c. hoyaCHD probes, coupled with the Griffiths P2/P8 primers, were validated to provide accurate and high-throughput gender identification for many Accipitridae species.

Effect of perceived stigmatization on the quality of life among ageing female family carers: a comparison of carers of adults with intellectual disability and carers of adults with mental illness

BACKGROUND

Little account has been taken of quality of life (QoL) among family carers of adults with an intellectual disability (ID) and family carers of adults with a mental illness (MI), particularly the female ageing carers' perceived stigma. We explore whether there are differences in the significant predictors of female ageing family carers' QoL between family carers of adults with ID and family carers of adults with MI and aim to examine the effect of these differences in stigma on carer QoL between the two groups.

METHODS

A structural survey interview was administered to 350 female family carers supporting persons with ID and 66 female carers supporting persons with MI; the carers were aged 55 years and older, and the interviews were carried between July 2006 and April 2007 at the carers' homes in a county in Taiwan. The survey package contained standardised scales to measure the carer's stigma, social support, QoL and health as well as adult and carer socio-demographic data.

RESULTS

The results highlight that in both groups the ageing female family carers' health and social support were strongly associated with the level of their QoL even though there was also a strong effect of carers' perceived stigma on their QoL. Contrary to previous findings, ageing female family carers of adults with MI had a higher level of QoL compared with the carers of adults with ID. Hierarchical regressions show a stronger effect of perceived stigma on the carer QoL among the family carers of adults with MI than among the carers of adults with ID.

CONCLUSIONS

This study suggests that attempts to improve these female older family carers' health and social support must include their lifelong unmet needs in terms of how to cope with the perceived stigma associated with their position.

Elasticity transition and loop formation in vibrated bead chains: a simulation of polymer chains

By measuring the distribution function of the end-to-end distance, we find that strongly shaken bead chains exhibit many properties, such as the rigid-rod-to-Gaussian chain transition, scaling, fast drop of loop formation probability in the short-chain regime, and enhancement of loop formation probability for kinked chains, of long-chain polymers. Though there is difference in local details between our chains and the worm-like chains, our results are consistent with recent calculations based on the worm-like chain model in many respects.

Overexpression of progesterone receptor A isoform in mice leads to endometrial hyperproliferation, hyperplasia and atypia

A delicate balance in estrogen and progesterone signaling through their cognate receptors is characteristic for the physiologic state of the endometrium, and a shift in receptor isotype expression can be frequently found in human endometrial pathology. In this study, using a transgenic mouse model, we examined the mechanisms whereby alterations in progesterone receptor (PR) isotype expression leads to endometrial pathology. For an experimental model, we used transgenic mice (PR-A transgenics) carrying an imbalance in the native ratio of the two PR isoforms A and B (PR-A and PR-B) through the expression of additional A form and examined their uterine phenotype under different hormonal regimens, using various criteria. Uterine epithelial cell proliferation was augmented in PR-A transgenics and was abolished by PR antagonists. In particular, proliferative response to progesterone, independent of signaling through estrogen, was enhanced. Upon continuous exposure to estradiol and progesterone, the uteri in PR-A transgenics displayed gross enlargement, endometrial hyperplasia including atypical lesions, endometritis and pelvic inflammatory disease. Imbalanced expression of the two isoforms of PR in a transgenic model reveals multiple derangements in the regulation of uterine physiology, resulting in various pathologies including hyperplasias.

Anti-inflammatory effects of dimemorfan on inflammatory cells and LPS-induced endotoxin shock in mice

BACKGROUND AND PURPOSE

Dimemorfan (a sigma1 receptor agonist) showed neuroprotective properties in animal models of inflammation-mediated neurodegenerative conditions, but its effects on inflammatory cells and systemic inflammation remain unclear.

EXPERIMENTAL APPROACH

The effects of dimemorfan on phorbol-12-myristate-13-acetate (PMA)- and N-formyl-methionyl-leucyl-phenylalanine (fMLP)- induced neutrophils and lipopolysaccharide (LPS)-activated microglial cells, as well as LPS-induced endotoxin shock in mice were elucidated.

KEY RESULTS

Dimemorfan decreased PMA- and fMLP-induced production of reactive oxygen species (ROS) and CD11b expression in neutrophils, through mechanisms independent of sigma1 receptors, possibly by blocking ROS production and G-protein-mediated intracellular calcium increase. Dimemorfan also inhibited LPS-induced ROS and nitric oxide (NO) production, as well as that of monocyte chemoattractant protein-1 and tumour necrosis factor-alpha (TNF-alpha), by inhibition of NADPH oxidase (NOX) activity and suppression of iNOS up-regulation through interfering with nuclear factor kappa-B (NF-kappaB) signalling in microglial cells. Treatment in vivo with dimemorfan (1 and 5 mg kg(-1), i.p., at three successive times after LPS) decreased plasma TNF-alpha, and neutrophil infiltration and oxidative stress in the lung and liver.

CONCLUSIONS AND IMPLICATIONS

Our results suggest that dimemorfan acts via sigma1 receptor-independent mechanisms to modulate intracellular calcium increase, NOX activity, and NF-kappaB signalling, resulting in inhibition of iNOS expression and NO production, and production of pro-inflammatory cytokines. These effects may contribute its anti-inflammatory action and protective effects against endotoxin shock in mice.

Temporal relationship between hepatitis B virus enhancer II/basal core promoter sequence variation and risk of hepatocellular carcinoma

BACKGROUND AND AIMS

To investigate the temporal relationship between sequence variation in the enhancer II (EnhII), basal core promoter (BCP), and precore regions of hepatitis B virus (HBV) and the risk of hepatocellular carcinoma (HCC), we conducted a nested case-control study within a cohort of 4841 male HBV carriers who were recruited during the period 1988-1992.

METHODS

The HBV DNA sequence was determined in baseline blood samples taken from 132 incident cases and 204 controls. Base exchanges during follow-up in 71 cases were compared with 81 controls with samples taken during a similar length of follow-up.

RESULTS

Nine single nucleotide polymorphisms in the EnhII/BCP regions (six of which were genotype C HBV related) were associated with subsequent risk of HCC. The strength of these associations decreased as the lag time between baseline measurement and diagnosis increased over 3 years. However, an increased disease risk in subjects with BCP double variants (mostly T1762/A1764) or genotype C HBV-related variants was evident 9 years or more before diagnosis. The BCP double variants (odds ratio, 1.92 (95% confidence interval, 1.14 to 3.25)) were statistically significantly associated with HCC risk even after adjusting for alanine aminotransferase levels, antibodies against HBV e antigen, HBV genotype, HBV viral load, and other sequence variants. Longitudinal analysis indicated that the increased HCC risks for at-risk sequence variants were attributable to the persistence of these variants.

CONCLUSIONS

HCC risk is associated with sequence variation in the EnhII/BCP regions of HBV, and persistence of at-risk sequence variants is critical for HCC development.

Quality of life of adults with intellectual disabilities who live with families in Taiwan

BACKGROUND

Little research has been conducted about the quality of life (QOL) of people with intellectual disabilities (ID) in Taiwan, particularly their subjective QOL. This study examined the personal perceptions of these individuals as measured on internationally recognized core QOL domains and indicators.

METHODS

A census interview survey was conducted in Hsin-Chu City in Taiwan; 233 adults aged over 16 years with mild ID and living with their families participated in the study. Data were collected using the Cross-Cultural QOL Indicators (CCQOLI) together with socio-demographic data that included 'activities of daily living' and 'instrumental activities of daily living' (IADL). The CCQOLI were based on the three most commonly reported indicators of each of the eight QOL domains: emotional well-being, interpersonal relations, material well-being, personal development, physical well-being, self-determination, social inclusion and rights. Each indicator has two sets of questions related to the indicator's 'importance' and 'use'. These are answered by the respondent using a 4-point Likert scale.

RESULTS

The importance and use of the QOL indicators were evaluated positively by the respondents. The adults' individual characteristics, namely IADL and educational level, were significant predictors for the 'importance' while the adults' perceptions of 'use' for overall QOL were significantly affected by his/her socio-economic data, that is, residence location and father's educational level.

CONCLUSIONS

The present study addressed the issue of self-reported QOL in people with ID in Taiwanese society, becoming a possible benchmark for similar measurements carried out by disability movements there. These results contribute to current advocacy efforts towards creating a supportive environment for people with ID.

Trends in residential policies and services for people with intellectual disabilities in Taiwan

BACKGROUND

In Taiwan, 92-95% of people with an intellectual disability (ID) live with their families, with the remaining residing in residential facilities. Instead of funding community-living alternatives, the Taiwanese Government funds only registered facilities as part of its residential policies and services. The purpose of this study was to evaluate current policies and services trends regarding people with an ID in Taiwan.

METHODS

Both documentary research, such as an analysis of policies, services programmes, official statistics, surveys, reports and funding provision reports, and a mail survey, were conducted to examine current trends and characteristics of the 96 residential settings available for people with an ID in Taiwan.

RESULTS

During the 1990s in Taiwan, residential programmes for people with an ID showed the biggest growth since 1952. Since the first 'Community Home' was launched in 1990, the number of smaller scale residential settings with a unit size of less than 30 has grown significantly, particularly since 2000. However, the rate of institutionalization of people with an ID and who live in the institutions has also risen.

CONCLUSIONS

In Taiwan, unlike in Western societies, residential services for people with an ID provided by formal care systems are tending to grow in number, and these include both large and smaller residential settings.

Establishment and characterization of a spontaneously immortalized porcine mammary epithelial cell line

We have established a spontaneously immortalized porcine mammary epithelial cell line (SI-PMEC) from the mammary gland of a lactating sow and maintained it long-term in culture by continuous subculturing. SI-PMEC cells were maintained for more than 8 months (70 passages) in DMEM/F12 medium supplemented with 10% fetal calf serum, insulin, and hydrocortisone without obvious signs of senescence. When grown at low density on a plastic substratum, SI-PMEC cells formed islands, and when grown to confluency, the cells formed a monolayer and aggregated with the characteristic cobblestone morphology of epithelial cells. The subcultured SI-PMEC cells appeared to proliferate without changes in morphology or growth pattern, with an estimated population doubling time of 20-22 h. With increasing density, SI-PMEC cells organized into lumen-like structures with elongated cells at the margins. SI-PMEC cells from stocks frozen at Passage 30 were subcultured up to 20 times without changes in cell viability, proliferation rate, or morphology. Furthermore, SI-PMEC cells remained immunopositive to an antibody against cytokeratin AE3 and immunonegative to an antibody against a human fibroblast antigen. The SI-PMEC cells could form functional structures resembling ducts, lateral-buds, and alveoli in a Matrigel matrix-dependent manner in vitro. When grown on the Matrigel and stimulated by prolactin, the cells differentiated and formed mammary gland structures and strongly expressed transcripts encoding the milk proteins alpha-lactalbumin, beta-casein, and beta-lactoglobulin. Our results indicate that the SI-PMEC cell line can be subpassaged many times and still form functional differentiated secretory structures. To our knowledge, this is the first report of an immortalized mammary epithelial cell line from pig.

Ultrastructure of the sperm of blue sprat, Spratelloides gracilis; Teleostei, Clupeiformes, Clupeidae

The general sperm structure of the investigated clupeoids possess an oliviform head with a distinct deep nuclear fossa, a midpiece with one mitochondrion and a posterior flagellum. They are characterized by two apomorphies: an annular or C-shaped mitochondrion and ITDs (intratubular differentiation) in the A tubules of the axonemal doublets. The fine structure of the spermatozoa of blue sprat, Spratelloides gracilis, was investigated to see if resulting data conformed to the current hypotheses of the taxonomy of the Clupeidae. The mature sperm is characterized by the following features: (1) the nucleus is oliviform; its prominent deep nuclear fossa encloses the initial portion of flagellum, (2) a proximal centriole has not been identified, (3) a single spherical mitochondrion is located laterally in relation to the flagellum and (4) no cytoplasmic canal is present. Our blue sprat-spermatozoan morphology data suggest that the blue sprat has Clupeomorpha affinities, while indicating no close affinity with Elopomorpha. Clupeoid sperm exhibit morphological variations with the nucleus and mitochondrion being particularly variable. This study provides useful systematic characters to the existing knowledge of comparative spermatology and may provide additional clue to Euteleost phylogeny.

Gene transfection and expression in a primary culture of mammary epithelial cells isolated from lactating sows

Porcine mammary epithelial cells (PMECs) were isolated from lactating sow mammary glands and cultured on a matrix gel. Primary culture cells expressed significant amounts of the specific marker cytokeratin as determined by immunohistochemistry, and exhibited mammary-specific functions, such as transcription of alpha-lactalbumin, beta-casein and beta-lactoglobulin genes. They also formed mammospheres when the medium was supplemented with lactogenic hormones. The PMECs were used to study gene transfer and expression in vitro. A gene encoding enhanced green fluorescent protein (EGFP) was used as a reporter and two constructs were investigated, pEGFP-N1 (a vector constructed with a CMV promoter followed by the EGFP gene) and pGB562/GFP (a mammary gland-specific expression vector with regulatory sequences from the goat beta-casein gene linked to EGFP). The efficiency of DNA transfer into the cultured PMECs was about 20-30%. GFP expression in the pGB562/GFP-transfected PMECs was markedly stimulated by prolactin supplements in the medium. The established PMECs maintained optimal gene expression from 1 to 20 passages and appeared to provide an efficient and convenient system for assessing the expression of transgenes containing mammary gland-specific promoters.

Genital porokeratosis: a series of 10 patients and review of the literature

BACKGROUND

Porokeratosis (PK) is an uncommon disorder of epidermal keratinization with a unique clinical appearance, unknown aetiology, and an unpredictable outcome. Genital PK (defined as localized PK confined to the genital area in this study) is extremely rare and is not well documented.

OBJECTIVES

To evaluate the clinical manifestations, histopathology, clinical course and treatment response for genital PK.

METHODS

We reviewed the clinicohistological data from 10 patients with genital PK seen at Chang Gung Memorial Hospital from 1990 to 2005.

RESULTS

Seven patients had lesions only in the genital area, and three patients had genital and adjacent areas involved. All patients were male and the mean age at initial diagnosis was 46.0 years (range 36-59). All but one patient presented with pruritic lesions. Three patients (30%) had diabetes mellitus. No malignant transformation was observed. Surgical excision was the most effective treatment if it could be performed.

CONCLUSIONS

Genital PK appeared more frequently in the Asian population than in reports from western countries. Genital PK presented mostly as pruritic lesions in Taiwan, with a wide age distribution. Long-term follow-up might be needed.

Drug utilization pattern of Chinese herbal medicines in a general hospital in Taiwan

PURPOSE

Drug utilization studies are important for the optimization of drug therapy and have received a great attention in recent years. Most of the information on drug use patterns has been derived from studies in modern Western medicines; however, studies regarding the drug utilization of traditional Chinese medicine (CM) are few. The present study was the first clinical research to evaluate the drug utilization patterns of Chinese herbal medicines in a general hospital in Taiwan.

METHODS

Data were collected prospectively from the patients attending the Traditional Medicine Center of Taipei Veteran General Hospital under CM drug treatments. The study was carried out over a period of 1 year, from January 2002 to December 2002. Core drug use indicators, such as the average number of drugs per prescriptions, the dosing frequency of prescriptions, and the most common prescribed CM herbs and formulae were evaluated. The primary diagnosis and the CM drugs prescribed for were also revealed. All data were analyzed by descriptive statistics.

RESULTS

A total of 10 737 patients, representing 52 255 CM drugs, were screened during the study period. Regarding the prescriptions, the average number of drugs per prescription was 4.87 and 37.21% of prescriptions were composed by five drugs. Most of prescriptions (91.38%) were prescribed for three times a day. The most often prescribed Chinese herb was Hong-Hwa (5.76%) and the most common Chinese herbal formula was Jia-Wey-Shiau-Yau-San (3.80%). The most frequent main diagnosis was insomnia (15.58%), followed by menopause (5.22%) and constipation (5.09%).

CONCLUSION

The survey revealed the drug use pattern of CMs in a general hospital. The majority of CM prescriptions were composed by 3-6 drugs and often prescribed for three times a day. Generally, the rational drug uses of CM drugs were provided with respect to the various diagnoses.

Genetic variants of myeloperoxidase and catechol-O-methyltransferase and breast cancer risk

This nested case-control study evaluated the role of polymorphisms in the myeloperoxidase (MPO) and catechol-O-methyltransferase (COMT) genes that modulate oxidative stress in breast cancer risk in a Chinese population. Our results demonstrate that the MPO A/A genotype was associated with a reduced risk of breast cancer (odds ratio (OR) 0.64; 95% confidence interval (CI) 0.11-3.76), whereas there was no overall association of COMT genotype with breast cancer. Of note, an elevated breast cancer risk associated with the increasing numbers of high-risk genotypes of MPO and COMT genes was observed in women with a longer duration between menarche and first full-term pregnancy.

Hepatitis C virus infection-related Type 1 diabetes mellitus

BACKGROUND

Hepatitis C virus (HCV) has been associated with Type 2 diabetes mellitus, and many other viral infections have been associated with Type 1 diabetes mellitus (Type 1 DM). An association between HCV and Type 1 DM, however, has never been reported. We report the case of a 66-year-old man who developed Type 1 DM 1 year after a blood transfusion-related HCV infection. Testing of serum specimens obtained in the weeks following blood transfusion demonstrated evidence of both acute HCV infection and development of Type 1 DM-related autoantibodies.

CASE REPORT

A 66-year-old Taiwanese male received blood transfusions during coronary artery bypass surgery in 1987. Serum specimens, obtained as part of a study on post-transfusion hepatitis, demonstrated that the patient had no evidence of hepatitis C prior to transfusion, but developed acute HCV infection after transfusion. One year later, the patient, who had no personal or family history of diabetes, presented with diabetic ketoacidosis, and tests for C-peptide confirmed that he had Type 1 DM. Testing of pre- and post-operative serum specimens demonstrated that the patient developed positive tests for islet cell and glutamic acid decarboxylase antibodies 4 weeks after transfusion, concurrent with the development of acute HCV infection.

CONCLUSIONS

The simultaneous development of HCV infection and diabetes-related autoantibodies suggest a relationship between HCV and Type 1 DM.

Rational pharmacotherapy in the diabetic hypertension: analysis-prescribing patterns in a general hospital in Taiwan

OBJECTIVES

To examine prescribing at a 2800-bed hospital, also providing ambulatory services for 9000 visits per day, with a view to assessing the extent to which it followed international guidelines for treating diabetic hypertension.

METHOD

Patients receiving antidiabetic and antihypertensive drugs concomitantly during the 4-week study period were included.

RESULT

Of the 5015 eligible patients, most received combination antidiabetic therapy. Oral antidiabetic agents used alone or in combination included (in descending order) metformin, glibenclamide, gliclazide, glipizide, glimepiride and alpha-glucosidase inhibitors. Gliclazide accounted for most of the oral antidiabetic drug expenditure. Sulfonylurea plus metformin was the most popular regimen. Prescriptions for long-acting sulfonylureas did not differ between elderly and younger patients. For blood pressure control, calcium-channel blockers were most commonly used alone and overall, although current guidelines suggest that they should be second-line treatments. Inappropriate use of immediate-release nifedipine was noted. The combination, atenolol >100 mg/day and hydrochlorothiazide 50 mg/day (or an equivalent) were extensively used. Among 54.7% patients treated with combination antihypertensives, calcium-channel blockers and an angiotensin-converting enzyme inhibitor were most commonly used.

CONCLUSION

Most diabetic hypertensive patients were treated with combination therapy for glucose and blood pressure control. Prescriptions for antihypertensive drugs often differed from current guidelines, especially in the choice of agents and their combinations.

Cyclosporine enhances vasorelaxation in coronary but not pulmonary artery after 16-hour preservation with UW solution

Cyclosporine (CsA), a calcineurin inhibitor, has been associated with endothelial dysfunction in transplant patients. Human and in vitro studies suggest that CsA produces endothelial dysfunction by impairing vascular endothelium-dependent relaxation. However, little is know about the CsA effects to modulate the vasorelaxation after prolonged graft preservation. In this study using a protocol designed to eliminate the influences of infusion pressure and shear stress, we evaluated the effect of CsA on vasorelaxation of coronary and pulmonary arteries after 16-hour University of Wisconsin (UW) solution preservation.

Cellular expression of estrogen and progesterone receptors in mammary glands: regulation by hormones, development and aging

At present, there is an extensive body of literature documenting the participation of estrogen receptors (ER) and progesterone receptors (PR) in mammary gene expression. Yet, the precise roles of these receptors in regulating mammary development, carcinogenesis and the growth of a subset of tumors still remain unclear. Mammary glands are composed of various cell types with different developmental potentials. Further, ultimately, that it is their mutual interactions which dictate the behavior of mammary epithelial cells. Therefore, to resolve the roles of ER and PR in normal mammary growth, differentiation and carcinogenesis, analyses for the expression of these receptors at the level of individual cell types is of paramount importance. Accordingly, in the present studies using immunolocalization techniques, we document the ontogeny and cellular distribution of ER and PR during mammary development and in response to ovarian hormones and aging. In addition, we discuss the potential biological significances of the expression patterns of ER and PR during various physiological states. We believe that the observations reported here should provide a conceptual framework(s) for elucidating the roles of ER and PR in normal and neoplastic mammary tissues.

Identification of rat mammary tumor-1 gene (RMT-1), which is highly expressed in rat mammary tumors

Full-term pregnancy early in life results in a permanent reduction in lifetime breast cancer risk in women. Parous rats and mice are also refractory to chemical carcinogenesis. Therefore, investigation of the differences between mammary glands from virgin and parous rats would provide valuable information regarding the protective effects of early full-term pregnancy. In this report, we examined the gene expression patterns in mammary glands from virgin and parous Lewis rats. Using differential display technology, a novel 4.2 kb cDNA, designated rat mammary tumor-1 (RMT-1) was isolated. Northern blot analysis of RMT-1 showed that RMT-1 expression was higher in the pre-pubertal and pubertal stages during rat mammary gland development while it was down-regulated in mammary glands from mature virgin and parous rats. RMT-1 expression was highest in rat mammary cancers compared with either the mammary glands of virgin or parous rats. At the Northern blot sensitivity level, RMT-1 expression was found only in the mammary gland. Northern blot analysis also showed that the expression of this gene was found in 74% of N-methyl-nitrosourea (MNU)-induced mammary cancers while it was not found in MNU-induced cancers from other organs. The examination of the RMT-1 gene structure revealed that it consists of five exons spanning 5.9 kb. Using fluorescence in situ hybridization, the gene was localized on rat chromosome 1 band q 43-51. The present data show that there is a correlation between high RMT-1 expression and rat mammary carcinogenesis or decreased RMT-1 expression and parity associated refractoriness to chemically induced mammary carcinogenesis. However, whether or not RMT-1 gene has a functional role in these processes remains to be investigated.

Growth and characterization of N-methyl-N-nitrosourea-induced mammary tumors in intact and ovariectomized rats

It is well established that 85-90% of chemically induced mammary tumors in rats will disappear or diminish significantly in size after the ovaries are removed from the animal. However, it is less well established whether a high percentage of these mammary tumors will grow back with prolonged time after ovariectomy. It is also not known what changes in gene expression take place in the tumors as they develop an independence from hormones for growth. This study was carried out to investigate this. Virgin, 50-day-old female Sprague-Dawley rats were injected with N-methyl-N-nitrosourea (MNU) at the dose of 50 mg MNU/kg body wt. When at least one mammary tumor had grown to 1.0-1.5 cm in one dimension, the animal was bilaterally ovariectomized and reduction and then re-growth of the tumors monitored. Control animals were treated identically except they were not ovariectomized when tumors appeared. Re-growths and new tumors and tumors that developed in the control rats were removed when they reached 1.0-1.5 cm in diameter and all animals were killed 25 weeks after the MNU injection. All the animals in the study (100%) developed mammary tumors after MNU injection with an average latency of 56.5 days. After ovariectomy, 93% of the tumors showed 50% or more reduction in size and 76% of the tumors could not be detected by palpation. However, in 96% of the animals where tumor reduction or disappearance occurred, a re-growth or new mammary tumor development took place with an average latency period of 52.8 days from the day of ovariectomy. Of these post-ovariectomy tumors, 36% occurred at a location where tumors had developed prior to ovariectomy, but 64% appeared at new locations. The circulating levels of 17beta-estradiol (E2) was undetectable in the ovariectomized (OVX) rats and significant reduction was seen in the serum concentrations of progesterone (P4), prolactin (PRL), growth hormone (GH) and insulin-like growth factor-I (IGF-I). The tumors from the OVX rats showed indications of progression as evident from loss of differentiation and invasive characteristics. Comparison between tumors from OVX and intact rats revealed a significantly increased expression of P450 aromatase and elevated activation of extracellular signal-regulated kinase 1 and 2, but reduced levels of the progesterone receptor and cyclin D1 in OVX rats. However, the estrogen receptor (ER) content remained similar in tumors from both groups, at least at the protein level, and so did the expression of IGF-I, IGF-II, insulin receptor substrate-1 (IRS1), IRS-2 and epidermal growth factor receptor. IGF-I receptor (IGF-IR) and ErbB-2 were expressed, respectively, in 50 and 70% of the tumors from the OVX animals, whereas these genes were expressed in 100% of the tumors from the intact rats. It is concluded that chemically induced rat mammary tumors may still depend on the ER and local syntheses of E2 and growth factors for growth initially after ovariectomy. However, as these tumors progress, they develop a more aggressive phenotype and lose their dependency on the ER and possibly growth factors.

Catalytic nucleophilic acyl substitution of anhydrides by amphoteric vanadyl triflate

[reaction--see text] Among four vanadyl species examined, vanadyl triflate was the most efficient catalyst to facilitate nucleophilic acyl substitution of anhydrides with a myriad array of alcohols, amines, and thiols in high yields and high chemoselectivity. By using mixed-anhydride technique, one can achieve oleate and peptide syntheses. In marked contrast to common metal triflates, the amphoteric character of the V=O unit in vanadyl species was proven to be responsible for the catalytic profile in this process.