Influence of Obstructive Sleep Apnea on the Risk of Dental Caries: Insights from a 13-Year Population-Based Retrospective Study

KNOWLEDGE TRANSFER STATEMENT

Obstructive sleep apnea has been proven to have a great negative impact on patients, and the relationship between sleep apnea and dental caries is still inconclusive. Our study shows that patients with sleep apnea and those older than 45 y have a significant risk of dental caries.

Diagnosis and treatment outcomes of urethritis-like symptoms in young males: a retrospective cohort study

The study evaluated the prevalence of gonorrhoea and chlamydia infections and find out other non-infectious diseases in sexually active young males with urethritis-like symptoms and their treatment outcomes. We retrospectively reviewed the young adult males (aged 20-50 years) who visited our clinic with urethritis symptoms from March 2019 to April 2022. All patients underwent urinalysis, urine culture, and urinary polymerase chain reaction (PCR) testing for gonorrhoea and chlamydia. Student's t-test and Pearson's chi-square test were used to compare the differences between the triple-negative group (i.e., negative results in urinalysis, urine culture, and urinary PCR) and the any-positive group. Logistic regression analyses were used to evaluate the predictive factors for positive PCR results for gonorrhoea or chlamydia in patients with negative urinalysis and urine culture. Of the 365 participants with urethritis-like symptoms, 139 patients were diagnosed of gonococcal or chlamydia urethritis. Among the 202 patients with negative urinalysis and urine culture, 60 patients were diagnosed with gonorrhoea or chlamydia using PCR. Urethral discharge was an independent predictor. 142 patients with triple negative results were attributed to other non-infectious diseases. Empirical antibiotic treatment is recommended for patients with urethritis symptoms showing positive or negative urinalysis results but with urethral discharge.

Roles of Omega-3 Polyunsaturated Fatty Acids in Managing Cognitive Impairment in Chronic Obstructive Pulmonary Disease: A Review

Chronic obstructive pulmonary disease (COPD) contributes significantly to the death of people worldwide, especially the elderly. An essential feature of COPD is pulmonary inflammation, which results from long-term exposure to noxious substances from cigarette smoking and other environmental pollutants. Pulmonary inflammatory mediators spill over to the blood, leading to systemic inflammation, which is believed to play a significant role in the onset of a host of comorbidities associated with COPD. A substantial comorbidity of concern in COPD patients that is often overlooked in COPD management is cognitive impairment. The exact pathophysiology of cognitive impairment in COPD patients remains a mystery; however, hypoxia, oxidative stress, systemic inflammation, and cerebral manifestations of these conditions are believed to play crucial roles. Furthermore, the use of medications to treat cognitive impairment symptomatology in COPD patients has been reported to be associated with life-threatening adverse effects, hence the need for alternative medications with reduced side effects. In this Review, we aim to discuss the impact of cognitive impairment in COPD management and the potential mechanisms associated with increased risk of cognitive impairment in COPD patients. The promising roles of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) in improving cognitive deficits in COPD patients are also discussed. Interestingly, ω-3 PUFAs can potentially enhance the cognitive impairment symptomatology associated with COPD because they can modulate inflammatory processes, activate the antioxidant defence system, and promote amyloid-beta clearance from the brain. Thus, clinical studies are crucial to assess the efficacy of ω-3 PUFAs in managing cognitive impairment in COPD patients.

Preliminary results of COVID-19 vaccination among Taiwanese pregnant women: A single-center, prospective, case-control study

OBJECTIVE

To evaluate the impacts of messenger RNA coronavirus disease 2019 (COVID-19) vaccines in Taiwanese pregnant women in terms of obstetrical and neonatal outcomes.

METHODS

The authors prospectively followed up 450 pregnant women receiving vaccination at a single center. Patients recorded prespecified adverse reactions via a mobile application up to 30 days after the first and second doses. Obstetrical and neonatal outcomes were compared with those of pregnant women, during the same period, who did not undergo vaccination.

RESULTS

Among the 387 women who received the first dose and were followed up for 30 days, injection site pain, fatigue, injection site swelling, muscle ache, and headache were the most prevalent side effects. There were 4.7-, 5.7-, 7.1-, and 9.3-fold increases in fatigue, injection site swelling, muscle ache, and headache, respectively, among the 231 women who received the second dose. Most of the side effects resolved by 14 days and all resolved by 30 days after each doses. There were no significant differences (P > 0.05) in obstetrical and neonatal morbidity or mortality between the vaccinated and unvaccinated cohorts.

CONCLUSION

No serious adverse reactions were noted among pregnant women receiving messenger RNA vaccinations with comparable obstetrical and neonatal outcomes to unvaccinated pregnant women.

Comparison of simulation-based interprofessional education and video-enhanced interprofessional education in improving the learning outcomes of medical and nursing students: A quasi-experimental study

BACKGROUND

Use of interprofessional education has greatly expanded and is widely used to foster interprofessional collaborative practice competency in health professionals, especially during medical emergencies. Identifying the interprofessional education delivery mode that can maximize learning outcomes within available resources is crucial for achieving the sustainability of an interprofessional education program.

OBJECTIVES

To examine the learning outcomes of simulation-based interprofessional education and video-enhanced interactive discussion interprofessional education modules and to analyze the variable costs between these two interprofessional education modules.

DESIGN

A prospective quasi-experimental study.

SETTING

A medical university in Northern Taiwan.

PARTICIPANTS

24 medical students and 48 nursing students enrolled in a 4-week simulation-based interprofessional education or video-enhanced interactive discussion interprofessional education program.

METHODS

Students' medical task performance, critical medical task performance, team behavior performance, and interprofessional collaboration attitude were examined at the pretest and posttest by using an objective structured checklist and team performance rating scale with a hands-on simulation model and structured questionnaires. The variable costs for simulation-based interprofessional education and video-enhanced interactive discussion interprofessional education were estimated upon the completion of the course.

RESULTS

All learning outcomes significantly improved for both the groups from the pretest to posttest. After the intervention, the simulation-based interprofessional education group exhibited significantly higher scores in medical task performance, critical medical task performance and team behavior performance than the video-enhanced interactive discussion interprofessional education group at the posttest. No significant difference was noted in interprofessional collaboration attitude between the groups. Cost analysis revealed that the simulation-based interprofessional education program was approximately two times more expensive in terms of staffing costs and required 1.3 times greater space charges than the video-enhanced interactive discussion interprofessional education program.

CONCLUSION

Both simulation-based interprofessional education and video-enhanced interactive discussion interprofessional education modules effectively improved medical and nursing students' medical task performance, critical medical task performance and team behavior performance. The simulation-based interprofessional education group had more favorable learning outcomes, but the associated costs were higher. Educators should consider both learning outcomes and cost when choosing a design strategy simulation-based interprofessional education vs. video-enhanced interactive discussion interprofessional education for interprofessional education module development.

Cervical verrucous cancer misdiagnosed with verrucous hyperplasia: A case report

Background

There are many different variants of squamous cell carcinoma (SCC), and verrucous carcinoma (VC) is a rare and highly differentiated SCC. Due to its preference of local invasion, regional lymphatic involvement rarely occurs. VC is difficult to diagnose using conventional pap smear or cervical punch biopsy, in which adequate stroma including bulbous rete pegs is required for a definitive diagnosis. Surgical management is recommended as the first-line treatment with radiotherapy forbidden due to the risk of anaplastic transformation.

Case report

We presented a 59-year-old Taiwanese female who had postmenopausal bleeding for three months with two consecutive normal pap smear and biopsy at other hospital. Pelvic examination showed a necrotic fungating cervical mass with upper 1/3 vaginal involvement. Colposcopic guided cervical biopsy and fractional dilatation and curettage revealed verrucous hyperplasia (VH) with negative high-risk HPV typing. Pelvic 3T magnetic resonance imaging (MRI) was arranged, and a 3.7 × 3.6 × 4.0 cm necrotic mass at the cervix with an enlarged left pelvic lymph node was found. Positron emission tomography with computed tomography (PET/CT) demonstrated avid uptake at the cervix and left pelvic lymph node. Surgical intervention was performed due to highly suspicious of cervical verrucous carcinoma with positive pelvic lymph node. The final pathologic report was a well-differentiated verrucous carcinoma, IIA2 by International Federation of Gynecology and Obstetrics (FIGO) classification.

Conclusion

VC is difficult to diagnose preoperatively, and surgical excision is recommended as the first-line treatment.

Effects of heavy metals in acute ischemic stroke patients: A cross-sectional study

Cerebrovascular disease is the second commonest cause of mortality globally and among the commonest causes of disability. However, research executed to probe the heavy metal exposure-stroke incidence relationship is scarce. Accordingly, we executed our study to probe the relationship of heavy metal concentrations (ie, concentrations of lead [Pb], mercury [Hg], cadmium [Cd], and arsenic) in the serum and urine of acute ischemic stroke (AIS) patients with several patient variables.For enrollment, we chose patients who had a first AIS within 7 days after the onset of a stroke. Thus, 33 newly diagnosed patients with AIS were recruited. We determined the aforementioned metals' concentrations by executing inductively coupled plasma mass spectrometry. We also gauged the association between such metal concentrations and patient variables by employing Spearman correlation coefficient. To examine the differences in metal concentrations between the different variables, we implemented an independent Mann-Whitney U test.In our cohort analysis, we noted serum Pb and Cd concentrations to be positively correlated with serum creatinine and hemoglobin. Serum and urine Cd concentrations had a negative correlation with impaired HbA1c in AIS patients. Urine Hg had a positive correlation with C-reactive protein in the participants. Participants who smoked or consumed alcohol had significantly higher Pb and Cd levels in serum than did those who neither smoked nor drank. Patients with AIS who smoked or consumed alcohol had high levels of serum Pb and serum Cd than did those who did not. Patients with AIS who consumed alcohol had significantly higher Pb and Hg urine concentrations than did those who did not.Our study indicated that serum Cd and Pb elevation increased the AIS risk in southern Taiwan patients.

Observation of Coexisting Weak Localization and Superconducting Fluctuations in Strained Sn1-xInxTe Thin Films

Topological superconductors have attracted tremendous excitement as they are predicted to host Majorana zero modes that can be utilized for topological quantum computing. Candidate topological superconductor Sn_1-xIn_xTe thin films (0 < x < 0.3) grown by molecular beam epitaxy and strained in the (111) plane are shown to host quantum interference effects in the conductivity coexisting with superconducting fluctuations above the critical temperature T_c. An analysis of the normal state magnetoresistance reveals these effects. A crossover from weak antilocalization to localization is consistently observed in superconducting samples, indicating that superconductivity originates dominantly from charge carriers occupying trivial states that may be strongly spin-orbit split. A large enhancement of the conductivity is observed above T_c, indicating the presence of superconducting fluctuations. Our results motivate a re-examination of the debated pairing symmetry of this material when subjected to quantum confinement and lattice strain.

Assessment of High Risk for Alzheimer's Disease Using Plasma Biomarkers in Subjects with Normal Cognition in Taiwan: A Preliminary Study

Background

In Alzheimer's disease (AD), cognitive impairment begins 10-15 years later than neurodegeneration in the brain. Plasma biomarkers are promising candidates for assessing neurodegeneration in people with normal cognition. It has been reported that subjects with the concentration of plasma amyloid-β 1-42×total tau protein higher than 455 pg²/ml² are assessed as having a high risk of amnesic mild impairment or AD, denoted as high risk of AD (HRAD).

Objective

The prevalence of high-risk for dementia in cognitively normal controls is explored by assaying plasma biomarkers.

Methods

422 subjects with normal cognition were enrolled around Taiwan. Plasma Aβ_1-40, Aβ_1-42, and T-Tau levels were assayed using immunomagnetic reduction to assess the risk of dementia.

Results

The results showed that 4.6% of young adults (age: 20-44 years), 8.5% of middle-aged adults (age: 45-64 years), and 7.3% of elderly adults (age: 65-90 years) had HRAD. The percentage of individuals with HRAD dramatically increased in middle-aged and elderly adults compared to young adults.

Conclusion

The percentage of HRAD in cognitively normal subjects are approximately 10%, which reveals that the potentially public-health problem of AD in normal population. Although the subject having abnormal levels of Aβ or tau is not definitely going on to develop cognitive declines or AD, the risk of suffering cognitive impairment in future is relatively high. Suitable managements are suggested for these high-risk cognitively normal population. Worth noting, attention should be paid to preventing cognitive impairment due to AD, not only in elderly adults but also middle-aged adults.

The predictive factors of nocturia in young Asian adult males: an online survey

The present study investigated the association between severity of depressive mood and nocturia in young Asian adult men. Participants were 3127 adult male Facebook users aged 20–40 years who could read and write traditional Chinese. Participants completed online questionnaires on demographic characteristics, frequency of waking to urinate during the night (International Prostate Symptoms Score [IPSS]), and frequency of depressive symptoms (Taiwanese Depression Questionnaire [TDQ]). Those who awoke to pass urine during the main sleep period were considered to have nocturia. Student’s t test and Pearson’s chi square test were used to compare participants with and without nocturia. Univariate and multivariate logistic regression were used to evaluate predictive factors for nocturia. One thousand four hundred thirty (45.7%) participants had nocturia, and 21.9% were suspected to have depression. Age over 30 years, body mass index over 25 kg/m², and higher IPSS score (except times of nocturnal voiding) were factors predictive of nocturia. Higher TDQ somatic subscores, rather than affective/cognitive subscores, were also predictive of nocturia. Associations were found between normal-high TDQ scores and nocturia. Young men with nocturia at risk of developing depression should be identified with a culturally relevant questionnaire. Early referral for psychiatric assessment and intervention may be warranted.

Direct and Knock-on Effects of Water Stress on the Nutrient Contents of Triticum aestivum (Poales: Poaceae) and Population Growth of Rhopalosiphum padi (Hemiptera: Aphididae)

To ascertain the direct effects of water stress upon wheat plants (Triticum aestivum L.) and how these effects, in turn, influence the population growth of the bird cherry-oat aphid (Rhopalosiphum padi L.), we conducted a physiological analysis of wheat seedlings grown under three different watering regimes and subsequently determined the population parameters of the aphid using the age-stage, two-sex life table. A significantly higher content of free amino acids and soluble sugars were observed in wheat seedlings exposed to drought stress compared to seedlings that were well-watered and those that were grown under waterlogged conditions. Extended phloem salivation and stylet penetration with shorter duration of sustained ingestion from phloem was observed in an electrical penetration graph (EPG) of R. padi on drought-stressed wheat seedlings. This suggested that the aphid's feeding activity, as well as nutrient intake, were impeded. The significantly higher percentage of essential amino acids found in wheat seedlings grown under waterlogged conditions promoted significantly higher fecundity and intrinsic rate of increase in R. padi populations compared to aphids fed on drought-treated or well-watered wheat seedlings. Our findings suggest that wheat seedling responses to water stress involve changes in sap composition that are responsible for altering the aphids' nutrient intake and consequently affect their population growth. From a grower's perspective, extending wheat cultivation in a rice-wheat rotation paddy field during the winter season may not be economically profitable if the fields are chronically waterlogged, since this may potentially lead to a higher infestation of cereal aphids.

Inversion-Protected Higher-Order Topological Superconductivity in Monolayer WTe_{2}

Monolayer WTe_{2}, a centrosymmetric transition metal dichacogenide, has recently been established as a quantum spin Hall insulator and found superconducting upon gating. Here we study the pairing symmetry and topological nature of superconducting WTe_{2} with a microscopic model at mean-field level. Surprisingly, we find that the spin-triplet phases in our phase diagram all host Majorana modes localized on two opposite corners. Even when the conventional pairing is favored, we find that an intermediate in-plane magnetic field exceeding the Pauli limit stabilizes an unconventional equal-spin pairing aligning with the field, which also hosts Majorana corner modes. Motivated by our findings, we obtain a recipe for two-dimensional superconductors featuring "higher-order topology" from the boundary perspective. Generally, a superconducting inversion-symmetric quantum spin Hall material whose normal-state Fermi surface is away from high-symmetry points, such as gated monolayer WTe_{2}, hosts Majorana corner modes if the superconductivity is parity-odd. We further point out that this higher-order phase is an inversion-protected topological crystalline superconductor and study the bulk-boundary correspondence. Finally, we discuss possible experiments for probing the Majorana corner modes. Our findings suggest superconducting monolayer WTe_{2} is a playground for higher-order topological superconductivity and possibly the first material realization for inversion-protected Majorana corner modes without utilizing proximity effect.

H2O2-Based Method for Rapid Detection of Transgene-Free Rice Plants from Segregating CRISPR/Cas9 Genome-Edited Progenies

Genome-editing techniques such as CRISPR/Cas9 have been widely used in crop functional genomics and improvement. To efficiently deliver the guide RNA and Cas9, most studies still rely on Agrobacterium-mediated transformation, which involves a selection marker gene. However, several limiting factors may impede the efficiency of screening transgene-free genome-edited plants, including the time needed to produce each life cycle, the response to selection reagents, and the labor costs of PCR-based genotyping. To overcome these disadvantages, we developed a simple and high-throughput method based on visual detection of antibiotics-derived H₂O₂ to verify transgene-free genome-edited plants. In transgenic rice containing hygromycin phosphotransferase (HPT), H₂O₂ content did not change in the presence of hygromycin B (HyB). In contrast, in transgenic-free rice plants with 10-h HyB treatment, levels of H₂O₂ and malondialdehyde, indicators of oxidative stress, were elevated. Detection of H₂O₂ by 3,3′-diaminobenzidine (DAB) staining suggested that H₂O₂ could be a marker to efficiently distinguish transgenic and non-transgenic plants. Analysis of 24 segregating progenies of an HPT-containing rice plant by RT-PCR and DAB staining verified that DAB staining is a feasible method for detecting transformants and non-transformants. Transgene-free genome-edited plants were faithfully validated by both PCR and the H₂O₂-based method. Moreover, HyB induced overproduction of H₂O₂ in leaves of Arabidopsis, maize, tobacco, and tomato, which suggests the potential application of the DAB method for detecting transgenic events containing HPT in a wide range of plant species. Thus, visual detection of DAB provides a simple, cheap, and reliable way to efficiently identify transgene-free genome-edited and HPT-containing transgenic rice.

Patterns of parents' perspectives on protecting young children from secondhand smoke exposure: A Q-methodology study

AIMS

To identify and describe the various patterns of parents' perspectives on avoiding secondhand smoke exposure.

DESIGN

Q methodology was applied to investigate the parental perspectives of 50 parents.

METHODS

The study was implemented from September-December 2016. Forty-two Q-statements were constructed based on the literature related to parental attitudes and prevention practices regarding preventing young children from experiencing secondhand smoke exposure. A series of Q-sorts was performed by the participants to rank the statements into a Q-sort grid. PQMethod 2.35 software was used to perform principal component analysis to identify different patterns of parents' perspectives.

RESULTS

Five patterns of shared perspectives, which accounted for 62% of the total variance, were derived from the analysis: (a) lack of confidence to confront smokers in non-smoking areas; (b) awareness of health hazards but not ready to take preventive actions; (c) emphasis on parental responsibility and behavioural guidance; (d) awareness of health rights protected by legislation; and (e) strong willingness to take protective actions.

CONCLUSION

Our findings revealed the shared perspectives of five groups of parents. The exploration of clusters of parents could assist healthcare professionals in acknowledging parents' tendencies related to attitudes and responses towards secondhand smoke exposure.

IMPACT

Using a forced distribution through the Q-sorting technique, the particular perspective patterns of parents' experiences would be captured. These findings can serve as a useful guide for researchers and practitioners to develop tailored intervention programs for parents with the purpose of reducing secondhand smoke exposure in young children.

Baroreceptor Sensitivity Predicts Functional Outcome and Complications after Acute Ischemic Stroke

Autonomic dysfunctions including impaired baroreflex sensitivity (BRS) can develop after acute ischemic stroke (AIS) and may predispose patients to subsequent cardiovascular adverse events and serve as potential indicators of long-term mortality. This study aimed to determine the potential short-term prognostic significance of BRS after AIS. All patients admitted to Kaohsiung Veterans General Hospital within 72 h after onset of first-ever AIS between April 2008 and December 2012 were enrolled. Autonomic evaluation with continuous 10-minute monitoring of beat-to-beat hemodynamic and intracranial parameters was performed within 1 week after stroke by using the Task Force Monitor and transcranial Doppler. The 176 enrolled AIS patients were divided into high-BRS and low-BRS groups. All but two enrolled patients (who died within 3 months after stroke) attended scheduled follow-ups. The high-BRS group had significantly lower National Institutes of Health Stroke Scale (NIHSS) scores at 1 and 2 weeks after stroke and at discharge; lower modified Rankin scale (mRS) scores 1, 3, 6, and 12 months after stroke; and lower rates of complications and stroke recurrence compared to the low-BRS group. This study provides novel evidence of the utility of BRS to independently predict outcomes after AIS. Furthermore, modifying BRS may hold potential in future applications as a novel therapeutic strategy for acute stroke.

Machine Learning Many-Body Localization: Search for the Elusive Nonergodic Metal

The breaking of ergodicity in isolated quantum systems with a single-particle mobility edge is an intriguing subject that has not yet been fully understood. In particular, whether a nonergodic but metallic phase exists or not in the presence of a one-dimensional quasiperiodic potential is currently under active debate. In this Letter, we develop a neural-network-based approach to investigate the existence of this nonergodic metallic phase in a prototype model using many-body entanglement spectra as the sole diagnostic. We find that such a method identifies with high confidence the existence of a nonergodic metallic phase in the midspectrum at an intermediate quasiperiodic potential strength. Our neural-network-based approach shows how supervised machine learning can be applied not only in locating phase boundaries but also in providing a way to definitively examine the existence or not of a novel phase.

Insights into GABAAergic system alteration in Huntington's disease

Huntington's disease (HD) is an autosomal dominant progressive neurodegenerative disease that is characterized by a triad of motor, psychiatric and cognitive impairments. There is still no effective therapy to delay or halt the disease progress. The striatum and cortex are two particularly affected brain regions that exhibit dense reciprocal excitatory glutamate and inhibitory gamma-amino butyric acid (GABA) connections. Imbalance between excitatory and inhibitory signalling is known to greatly affect motor and cognitive processes. Emerging evidence supports the hypothesis that disrupted GABAergic circuits underlie HD pathogenesis. In the present review, we focused on the multiple defects recently found in the GABAergic inhibitory system, including altered GABA level and synthesis, abnormal subunit composition and distribution of GABA_A receptors and aberrant GABA_A receptor-mediated signalling. In particular, the important role of cation–chloride cotransporters (i.e. NKCC1 and KCC2) is discussed. Recent studies also suggest that neuroinflammation contributes significantly to the abnormal GABAergic inhibition in HD. Thus, GABA_A receptors and cation–chloride cotransporters are potential therapeutic targets for HD. Given the limited availability of therapeutic treatments for HD, a better understanding of GABAergic dysfunction in HD could provide novel therapeutic opportunities.

Association between heavy metal levels and acute ischemic stroke

Background

Few studies have examined the relationship between the amounts of heavy metal and stroke incidence. The aim of this study was to explore the relationship between levels of heavy metals, including Pb, Hg, As, and Cd, in patients with acute ischemic stroke (AIS).

Methods

We selected patients with first-ever AIS onset within 1 week as our study group. Healthy controls were participants without a history of stroke or chronic disease, except hypertension. The serum levels of Pb, Hg, As, and Cd in participants in the experimental and control groups were determined. All participants received a 1-g infusion of edetate calcium disodium (EDTA). Urine specimens were collected for 24 h after EDTA infusion and measured for heavy metal levels.

Results

In total, 33 patients with AIS and 39 healthy controls were enrolled in this study. The major findings were as follows: (1) The stroke group had a significantly lower level of serum Hg (6.4 ± 4.3 μg/L vs. 9.8 ± 7.0 μg/L, P = 0.032, OR = 0.90, 95% CI = 0.81–0.99) and a lower level of urine Hg (0.7 ± 0.7 μg/L vs. 1.2 ± 0.6 μg/L, P = 0.006, OR = 0.27, 95% CI = 0.11–0.68) than the control group. (2) No significant difference in serum Pb (S-Pb), As (S-As), and Cd (S-Cd) levels and urine Pb (U-Pb), As (U-As) and Cd (U-Cd) levels was observed in either group.

Conclusions

Our study found low levels of serum and urine Hg in first-ever patients with AIS, providing new evidence of dysregulated heavy metals in patients with AIS.

Electronic supplementary material

The online version of this article (10.1186/s12929-018-0446-0) contains supplementary material, which is available to authorized users.

Altered behavioral responses to gamma-aminobutyric acid pharmacological agents in a mouse model of Huntington's disease

BACKGROUND

Disruptions in gamma-aminobutyric (GABA) acid signaling are believed to be involved in Huntington's disease pathogenesis, but the regulation of GABAergic signaling remains elusive. Here we evaluated GABAergic signaling by examining the function of GABAergic drugs in Huntington's disease and the expression of GABAergic molecules using mouse models and human brain tissues from Huntington's disease.

METHODS

We treated wild-type and R6/2 mice (a transgenic Huntington's disease mouse model) acutely with vehicle, diazepam, or gaboxadol (drugs that selectively target synaptic or extrasynaptic GABA_A receptors) and monitored their locomotor activity. The expression levels of GABA_A receptors and a major neuron-specific chloride extruder (potassium-chloride cotransporter-2) were analyzed by real-time quantitative polymerase chain reaction, Western blot, and immunocytochemistry.

RESULTS

The R6/2 mice were less sensitive to the sedative effects of both drugs, suggesting reduced function of GABA_A receptors. Consistently, the expression levels of α1/α2 and δ subunits were lower in the cortex and striatum of R6/2 mice. Similar results were also found in 2 other mouse models of Huntington's disease and in Huntington's disease patients. Moreover, the interaction and expression levels of potassium-chloride cotransporter-2 and its activator (brain-type creatine kinase) were decreased in Huntington's disease neurons. These findings collectively suggest impaired chloride homeostasis, which further dampens GABA_A receptor-mediated inhibitory signaling in Huntington's disease brains.

CONCLUSIONS

The dysregulated GABAergic responses and altered expression levels of GABA_A receptors and potassium-chloride cotransporter-2 in Huntington's disease mice appear to be authentic and may contribute to the clinical manifestations of Huntington's disease patients. © 2017 International Parkinson and Movement Disorder Society.

Topological superconductivity in monolayer transition metal dichalcogenides

Theoretically, it has been known that breaking spin degeneracy and effectively realizing spinless fermions is a promising path to topological superconductors. Yet, topological superconductors are rare to date. Here we propose to realize spinless fermions by splitting the spin degeneracy in momentum space. Specifically, we identify monolayer hole-doped transition metal dichalcogenide (TMD)s as candidates for topological superconductors out of such momentum-space-split spinless fermions. Although electron-doped TMDs have recently been found superconducting, the observed superconductivity is unlikely topological because of the near spin degeneracy. Meanwhile, hole-doped TMDs with momentum-space-split spinless fermions remain unexplored. Employing a renormalization group analysis, we propose that the unusual spin-valley locking in hole-doped TMDs together with repulsive interactions selectively favours two topological superconducting states: interpocket paired state with Chern number 2 and intrapocket paired state with finite pair momentum. A confirmation of our predictions will open up possibilities for manipulating topological superconductors on the device-friendly platform of monolayer TMDs.

Conditions to realize topological superconductivity have long been known, but the materialization remains rare. Here, Hsu et al. report a strategy towards possible topological superconductivity in monolayer hole-doped transition metal dichalcogenide by splitting the spin degeneracy in momentum space.

An investigation into inflection-point instability in the entrance region of a pulsating pipe flow

This paper investigates the inflection-point instability that governs the flow disturbance initiated in the entrance region of a pulsating pipe flow. Under such a flow condition, the flow instability grows within a certain phase region in a pulsating cycle, during which the inflection point in the unsteady mean flow lifts away from the viscous effect-dominated region known as the Stokes layer. The characteristic frequency of the instability is found to be in agreement with that predicted by the mixing-layer model. In comparison with those cases not falling in this category, it is further verified that the flow phenomenon will take place only if the inflection point lifts away sufficiently from the Stokes layer.

Effects of the traditional Chinese herb Astragalus membranaceus in patients with poststroke fatigue: A double-blind, randomized, controlled preliminary study

BACKGROUND AND PURPOSE

Astragalus membranaceus (AM) is the first-choice herb for fatigue treatment in traditional Chinese medicine and the main herb used for stroke treatment in China and Taiwan. The purpose of this study was to evaluate the effect of AM on poststroke fatigue (PSF).

MATERIALS AND METHODS

This study was designed as a double-blind, randomized, controlled preliminary study. Sixty-four patients with PSF were assigned to treatment group (TG; 31 patients), which received oral administration of AM (2.8g three times per day) for 28 days, and a control group (CG; 33 patients), which received a placebo. The primary outcome measures were the changes in the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and Brief Fatigue Index (BFI) scores RESULTS: A total of 61 patients (29 patients in the TG and 32 patients in the CG) completed the trial. The difference in BFI scores between Visit 2 and Visit 1 was -17.83±17.70 in the TG, which was greater than that in the CG (-8.03±9.95; p=0.01); additionally, the difference in BFI scores between Visit 3 and Visit 1 was -16.48±16.41 in the TG, which was also greater than that in the CG (-9.47±13.39; p=0.05). In the EORTC QLQ-C30, the difference in cognitive functioning scores between Visit 2 and Visit 1 was 14.37±13.89 in the TG, which was greater than that in the CG (3.65±19.74; p=0.02); additionally, the difference in these scores between Visit 3 and Visit 1 was 14.37±16.50 in the TG, which again was greater than that in the CG (6.25±19.74; p=0.04). The difference in social functioning scores between Visit 3 and Visit 1 was 9.77±15.12 in the TG, which was greater than that in the CG (-1.56±20.46; p=0.01). The difference in global quality of life (QOL) scores between Visit 2 and Visit 1 was 14.08±18.78 in the TG, which was also greater than that in the CG (1.56±18.14; p=0.003); moreover, the difference in these scores between Visit 3 and Visit 1 was 10.92±17.55 in the TG, and this was greater than that in the CG (1.82±15.8; p=0.05).

CONCLUSION

AM can improve BFI scores; cognitive functioning, social functioning, and global QOL scores in the EORTC QLQ-C30. Our results suggest that physicians should pay close attention to the unmet medical needs of patients with PSF. AM is helpful for treating patients with PSF; however, additional studies with a larger sample and a longer period of investigation are required.

Increased Risk of Depression in Patients with Parkinson Disease: A Nationwide Cohort Study

OBJECTIVE

The association between Parkinson disease (PD) and depression remains unclear, particularly in the Asian population. The purpose of this study is to investigate the risk of depression in patients with PD using population-based data.

METHODS

Based on the National Health Insurance Research Database of Taiwan, we identified 1,698 patients with PD aged 40 years or older diagnosed in 2000-2003. With frequency matching procedure, we randomly selected 6,792 subjects without PD stratified by sex and age. Both cohorts were followed until the end of 2008 or diagnosis of depression. Risk of depression associated with PD was estimated in the multivariate Cox hazards regressions. Diabetes, hypertension, and hyperlipidemia were more prevalent at baseline in patients with PD.

RESULTS

Compared with the cohort without PD, the hazard ratio (HR) for depression in PD patients was 4.06 (95% CI: 3.15-5.23), which increased to 4.26 (95% CI: 3.29-5.51) after adjustment for age, sex, urbanization, income, and coexisting medical conditions. In the sex stratification, the HR of depression for men with PD was 4.42 (95% CI: 2.93-6.67) compared with men without PD. The HR for the association between PD and depression in women was 4.22 (95% CI: 3.02-5.88).

CONCLUSION

This study suggests that patients with PD are at an elevated risk of depression, particularly for men. Integrated care for early identification and treatment of depression are crucial for patients with PD.

A novel soybean (Glycine max) gene encoding a family 3 β-glucosidase has high isoflavone 7-O-glucoside-hydrolyzing activity in transgenic rice

A previous study demonstrated that purified Glycine max β-glucosidase (GmBGL) could hydrolyze glucosyl isoflavone to the aglyconic form. This study reports the cloning and functional characterization of a soybean cDNA encoding the β-glucosidase. GmBGL was isolated by use of a purified soybean N-terminal amino acid sequence and conserved sequences of β-glucosidase genes from other plants. Sequence analysis of GmBGL revealed an open reading frame of 1884 bp encoding a polypeptide of 627 amino acids with a calculated molecular mass of 69 kDa. Phylogenetic analysis classified the GmBGL into the glycosyl hydrolase 3 family. In soybean, the GmBGL transcript was predominantly accumulated in roots and leaves. To examine the enzymatic activity and substrate specificity, GmBGL was ectopically expressed in transgenic rice. Purified GmBGL protein from transgenic rice could catalyze the hydrolysis of genistin and daidzin to produce genistein and daidzein, respectively, which confirmed GmBGL as a functional β-glucosidase with isoflavone glucoside-hydrolyzing activity. This paper reveals that GmBGL is a key enzyme in transforming glucosyl isoflavones to aglycones in soybean, which may help in genetic manipulation of aglycone-rich soybean seeds.

Dose effect of thiazolidinedione on cancer risk in type 2 diabetes mellitus patients: a six-year population-based cohort study

WHAT IS KNOWN AND OBJECTIVE

Prior studies found that thiazolidinediones (TZDs) might have tumour-suppressor activity mediated through cell-cycle arrest, induction of apoptosis and inhibition of cell invasion. The main objective of this study was to investigate the effects of TZDs on the risk of cancer among patients with type 2 diabetes mellitus (DM).

METHODS

Patients diagnosed with DM between 1 January 1998 and 31 December 2002 were identified from the Longitudinal Health Insurance Database (LHID) within the Taiwan National Health Insurance (NHI) programme. Using Cox regression models, we assessed the association between prescribed TZDs and cancer risk, TZDs' dose effect and the association between TZDs and specific cancer types. Hazard ratios (HR) were adjusted for potential confounders (age, gender, income, Charlson score index, metformin and insulin use).

RESULTS AND DISCUSSION

The adjusted HRs for those prescribed TZD were 0·74 (95% CI 0·43-1·26, P = 0·27), 0·39 (95% CI 0·33-0·45, P < 0·001) and 0·49 (95% CI 0·27-0·89, P = 0·02), respectively, relative to non-DM patients, DM patients prescribed other anti-DM drugs besides TZDs and DM patients not prescribed any anti-DM drugs. In addition, the effects of TZDs were shown to be significantly dose dependent (P for trend < 0·001). The risk of breast, brain, colorectal, ear-nose-throat, kidney, liver, lung, lymphatic, prostate, stomach, and uterus cancer was significantly lower in those prescribed TZDs.

WHAT IS NEW AND CONCLUSIONS

The results showed a decrease in cancer risk in diabetic patients using TZD, and the association was dose dependent.

Relationship between Chinese medicine pattern types, clinical severity, and prognosis in patients with acute cerebral infarct

We investigated the relationship between Chinese medicine pattern (CMP) types, their severity, and prognosis in patients (n = 187) with acute cerebral infarct (ACI). Six CMPs (wind, phlegm, fire-heat, blood stasis, qi deficiency, and yin deficiency and yang hyperactivity) were evaluated according to inspection, listening and smelling, inquiry, and palpitation. The severity and prognosis of each pattern type was determined according to the Glasgow Coma Scale (GCS), Modified Rankin Scale (MRS), National Institutes of Health Stroke Scale (NIHSS), Barthel Index (BI), and Functional Independence Measure (FIM), recorded at stroke onset and 12 weeks after stroke onset. The phlegm pattern (PP) patients displayed lower GCS, BI, and FIM scales scores, and higher MRS and NIHSS scales scores, than the nonphlegm pattern (N-PP) patients at, and 12 weeks after stroke onset, suggesting the clinical severity is greater and the prognosis is worse in PP patients with ACI than in non-PP patients with ACI.

Decreased risk of stroke in patients with traumatic brain injury receiving acupuncture treatment: a population-based retrospective cohort study

BACKGROUND

Patients with traumatic brain injury (TBI) face increased risk of stroke. Whether acupuncture can help to protect TBI patients from stroke has not previously been studied.

METHODS

Taiwan's National Health Insurance Research Database was used to conduct a retrospective cohort study of 7409 TBI patients receiving acupuncture treatment and 29,636 propensity-score-matched TBI patients without acupuncture treatment in 2000-2008 as controls. Both TBI cohorts were followed until the end of 2010 and adjusted for immortal time to measure the incidence and adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) of new-onset stroke in the multivariable Cox proportional hazard models.

RESULTS

TBI patients with acupuncture treatment (4.9 per 1000 person-years) had a lower incidence of stroke compared with those without acupuncture treatment (7.5 per 1000 person-years), with a HR of 0.59 (95% CI = 0.50-0.69) after adjustment for sociodemographics, coexisting medical conditions and medications. The association between acupuncture treatment and stroke risk was investigated by sex and age group (20-44, 45-64, and ≥65 years). The probability curve with log-rank test showed that TBI patients receiving acupuncture treatment had a lower probability of stroke than those without acupuncture treatment during the follow-up period (p<0.0001).

CONCLUSION

Patients with TBI receiving acupuncture treatment show decreased risk of stroke compared with those without acupuncture treatment. However, this study was limited by lack of information regarding lifestyles, biochemical profiles, TBI severity, and acupuncture points used in treatments.

Electrical stimulation to promote osteogenesis using conductive polypyrrole films

In this study, we developed an electrical cell culture and monitoring device. Polypyrrole (PPy) films with different resistances were fabricated as conductive surfaces to investigate the effect of substrate-mediated electrical stimulation. The physical and chemical properties of the devices, as well as their biocompatibilities, were thoroughly evaluated. These PPy films had a dark but transparent appearance, on which the surface cells could be easily observed. After treating with the osteogenic medium, rat bone marrow stromal cells cultured on the PPy films differentiated into osteoblasts. The cells grown on the PPy films had up-regulated osteogenic markers, and an alkaline phosphatase activity assay showed that the PPy films accelerated cell differentiation. Alizarin red staining and calcium analysis suggested that the PPy films promoted osteogenesis. Finally, PPy films were subjected to a constant electric field to elucidate the effect of electrical stimulation on osteogenesis. Compared with the untreated group, electrical stimulation improved calcium deposition in the extracellular matrix. Furthermore, PPy films with lower resistances allowed larger currents to stimulate the surface cells, which resulted in higher levels of mineralization. Overall, these results indicated that this system exhibited superior electroactivity with controllable electrical resistance and that it can be coated directly to produce medical devices with a transparent appearance, which should be beneficial for research on electrical stimulation for tissue regeneration.

Identification and characterization of a novel chloroplast/mitochondria co-localized glutathione reductase 3 involved in salt stress response in rice

Glutathione reductases (GRs) are important components of the antioxidant machinery that plants use to respond against abiotic stresses. In rice, one cytosolic and two chloroplastic GR isoforms have been identified. In this work, we describe the cloning and characterization of the full-length cDNA encoding OsGR3, a chloroplast-localized GR that up to now was considered as a non-functional enzyme because of assumed lack of N-terminal conserved domains. The expression of OsGR3 in E. coli validated that it can be translated as a protein with GR activity. OsGR3 shows 76 and 53 % identity with OsGR1 (chloroplastic) and OsGR2 (cytosolic), respectively. Phylogenetic analysis revealed 2 chloroplastic GRs in Poaceae species, including rice, sorghum and brachypodium, but only one chloroplastic GR in dicots. A plastid transit peptide is located at the N terminus of OsGR3, and genetic transformation of rice with a GR3-GFP fusion construct further confirmed its localization in chloroplasts. Furthermore, OsGR1 and OsGR3 are also targeted to mitochondria, which suggest a combined antioxidant mechanism in both chloroplasts and mitochondria. However, both isoforms showed a distinct response to salinity: the expression of OsGR3 but not OsGR1 was induced by salt stress. In addition, the transcript level of OsGR3 was greatly increased with salicylic acid treatment but was not significantly affected by methyl jasmonate, dehydration or heat shock stress. Our results provide new clues about the possible roles of functional OsGR3 in salt stress and biotic stress tolerance.

Zolpidem improves neuropsychiatric symptoms and motor dysfunction in a patient with Parkinson's disease after deep brain stimulation

PURPOSE

To illustrate the beneficial effect of zolpidem on the neuropsychiatric and motor symptoms in a patient with Parkinson disease (PD) after bilateral subthalamic nucleus deep brain stimulation.

CASE REPORT

The 61-year-old housewife was diagnosed to have PD for 12 years with initial presentation of clumsiness and rest tremor of right limbs. She was referred to our hospital in March 2009 due to shortening of drug beneficial period since 3 years ago and on-phase dyskinesia in recent 2 years. Bilateral STN DBS was conducted on 18 June, 2009. Fluctuating spells of mental confusion were developed on the next day after surgery. Electric stimuli via DBS electrodes were delivered with parameters of 2 volts, 60 μs, 130 Hz on bilateral STN 32 days after DBS. The incoherent behaviors and motor fluctuation remained to occur. The beneficial effect of zolpidem on her neuropsychiatric and motor symptoms was detected incidentally in early July 2009. She could chat normally with her caregiver and walk with assistance after taking zolpidem. The beneficial period may last for 2 hours. Zolpidem was then given in dosage of 10 mg three times per day. The neuropsychiatric inventory was scored 56 during zolpidem 'off' and 30 during zolpidem 'on'. To understand the intriguing feature, we conducted FDG-PET during 'off' and 'on' zolpidem conditions. The results revealed that the metabolism was decreased in the right frontal, parietal cortex and caudate nucleus during zolpidem 'off'. These cool spots can be partially restored by zolpidem.

CONCLUSION

Zolpidem ameliorated the neuropsychiatric and parkinsonian motor symptom in the PD patient. Since GABAA benzodiazepine receptors are widely distributed throughout the central nervous system, zolpidem probably acts via modulating structures lying within the cortico-subcortical loop or by direct effect on these cortical regions.

A patient with superficial siderosis, intraspinal cyst, low-pressure headache and low-lying cord

Superficial siderosis is a rare condition caused by deposition of hemosiderin in the central nervous system. In recent years, it has been used to identify dural defects connecting the intrathecal space with the intraspinal fluid-filled collection seen in patients with superficial siderosis. However rare reports describe the association of low-lying cord in superficial siderosis patients. We present a patient with progressive cerebellar ataxia, sensorineural hearing loss, low-pressure headache, pyramidal signs and additional cervical and lumbar radiculopathy with neurogenic bladder which might be related to cervical disc herniation and tethered cord. CSF and Magnetic resonance imaging (MRI) studies confirmed the diagnosis of superficial siderosis. Dural defect is indirectly suspected by existence of fluid-filled collection ventral to the spinal cord and low-pressure headache in our patient. Underlying causes of low-pressure headache and possible dural defect should be searched for as an associated and possibly treatable condition in superficial siderosis and provide further insights into the mechanism of bleeding in our patient who have an intraspinal fluid-filled collection.

The role of the sub-thalamic nucleus in the preparation of volitional movement termination in Parkinson's disease

The sub-thalamic nucleus (STN) is relevant to the preparation of movement ignition but its role in movement termination is uncertain. Fourteen patients with Parkinson's disease (PD) received local field potentials (LFPs) recording at the left STN on the fourth day after deep brain stimulation surgery. They performed phasic and tonic movements of the right wrist extensor. Movement onset (Mon) and movement offset (Moff) of the electromyographic activities were used as triggers to determine an eight-second LFPs epoch for time-frequency analysis. Movement-related power changes were assessed by repeated measures analysis of variance with within-subject factors of Event (Mon and Moff), Period (ten time periods for phasic movement and six time periods for tonic movement), and Frequency (alpha, low-beta, and high-beta). There was significant triple interaction in both the phasic and tonic movements. By post-hoc analysis, high-beta event-related de-synchronization (ERD) appeared earlier (3s prior to Mon) than those of low-beta and alpha for the Mon phasic movement. There was no alpha ERD for the Mon tonic movement. Alpha, low-beta, and high-beta ERD all appeared about 1s prior to the Moff tonic movement. The current findings suggest that STN participates in the preparation of volitional movement termination but via a different mechanism from that in movement initiation. Unlike asynchronous ERD frequency bands present in movement initiation, a simultaneous ERD across wide frequency bands in STN may play a pivotal role in terminating volitional movement.

Expression of genes involved in redox homeostasis and antioxidant defense in a marine macroalga Ulva fasciata by excess copper

The expression of genes involved in the control of redox homeostasis and antioxidant defense was studied in macroalga Ulva fasciata Delile in response to 5 and 50 microM CuSO(4). Redox-related genes, methionine sulfoxide reductase A (UfMsrA), thioredoxin (UfTrx), cyclophilin (UfCyp), and ferritin (UfFer) that were up-regulated by excess Cu [Wu, T.M., Lee, T.M., 2008. Regulation of activity and gene expression of antioxidant enzymes in Ulva fasciata Delile (Ulvales, Chlorophyta) in response to excess copper. Phycologia 47, 346-360] were cloned and their expression was compared to superoxide dismutase (UfMnsod and UfFesod), ascorbate peroxidase (UfApx), glutathione reductase (UfGr), and catalase (UfCat). Transcripts of UfMsrA, UfCyp, and UfFer were increased by excess Cu with a peak at 3h and that of UfTrx increased after 6-9h, but not affected by 4-day exposure to excess Cu, except an increase in UfMsrA transcript. Transcripts of UfMnsod, UfFesod, UfApx, UfGr and UfCat can be increased by 4-day exposure to Cu excess [Wu, T.M., Lee, T.M., 2008. Regulation of activity and gene expression of antioxidant enzymes in Ulva fasciata Delile (Ulvales, Chlorophyta) in response to excess copper. Phycologia 47, 346-360] but not by short-term excess Cu treatment, except UfGr whose transcript increased after 3h. Reactive oxygen species involved in up-regulation of antioxidant defense enzymes genes. These results suggest that the expression of genes of antioxidant defense enzymes and UfMsrA are associated with long-term adaptation of U. fasciata to Cu excess and transcription of redox-related genes and UfGr is up-regulated for short-term acclimation.

Acid-sensing ion channels in neurones of the rat suprachiasmatic nucleus

We used reduced slice reparations to study ASIC-like currents in the rat central clock suprachiasmatic nucleus (SCN). In reduced SCN preparations, a drop of extracellular pH evoked a desensitizing inward current to excite SCN neurones to fire at higher rates. Under voltage-clamped conditions, all SCN neurones responded to a 5 s pH step to 6.4 with an inward current that decayed with an average time constant of 1.2 s to 10% of the peak at the end of step. The current was blocked by amiloride with an IC(50) of 14 microm and was carried mainly by Na(+), suggesting an origin of ASIC-like channels. The SCN neurones were sensitive to neutral pH, with 94% of cells responding to pH 7.0 with an inward current. The study of sensitivity to pH between 7.0 and 4.4 revealed a two-component dose-dependent H(+) activation in most SCN neurones, with the first component (85% in amplitude) having a pH(50) of 6.6, and the second (15%) a pH(50) of 5. The ASIC-like currents were potentiated by lactate and low Ca(2+), but were inhibited by Zn(2+). RT-PCR analysis demonstrated the presence of mRNA for ASIC1a, 2a, 2b, and 3 in SCN. Compared to other central neurones, the unique presence of ASIC3 along with ASIC1a in SCN neurones may contribute to the high pH sensitivity and unusual inhibition by Zn(2+). The high pH sensitivity suggests that the SCN neurones are susceptive to extracellular acidification of physiological origins and that the ASIC current might play a role in regulating SCN excitability.

Hypersalinity and hydrogen peroxide upregulation of gene expression of antioxidant enzymes in Ulva fasciata against oxidative stress

The modulation of manganese superoxide dismutase (MnSOD), FeSOD, ascorbate peroxidase (APX), glutathione reductase (GR), and catalase (CAT) gene expression and activities and antioxidants in Ulva fasciata against hypersalinity (90 per thousand)-induced oxidative stress was studied. Increases in H(2)O(2) contents but no changes in lipid peroxidation and protein carbonyl group contents suggest oxidative damage did not occur in 90 per thousand condition. Antioxidants were consumed for reactive oxygen species (ROS) scavenging indicated by decreased ascorbate and glutathione contents by 90 per thousand. Antioxidant enzymes were differently expressed by 90 per thousand for ROS removal. MnSOD activity and transcript increased 1 h after 90 per thousand treatment with a peak at hour 3, while FeSOD activity increased fast to the plateau after 1 h and its transcript increased after 3 h. APX activity increased 1 h after 90 per thousand but its transcript rose till 3 h, and GR activity increased after 1 h with a peak at hour 3 but its transcript increased till 3 h. CAT activity and transcript increased after 12 h. Enzyme activity is transcriptionally regulated by 90 per thousand except a fast increase in FeSOD, APX, and GR activities during 1 h. APX is responsible for early H(2)O(2) decomposition while CAT scavenges H(2)O(2) in the later period. The inhibition of 90 per thousand induced increase of H(2)O(2) content and FeSOD activity and transcript by treatment of a H(2)O(2) scavenger, dimethylthiourea, and the increase of FeSOD transcript of 30 per thousand grown thalli by H(2)O(2) treatment suggest that H(2)O(2) mediates the upregulation of FeSOD by hypersalinity while other enzymes is modulated by factors other than H(2)O(2).

Increased circulatory MMP-2 and MMP-9 levels and activities in patients with type 1 diabetes mellitus

BACKGROUND

Type 1 diabetes mellitus (T1DM) is an autoimmune disorder of unknown etiology. It has been suggested that metalloproteinases (MMPs) play important roles in the development and complications of autoimmune disorders. This article presents our research on the expression or activities of MMPs in Taiwanese T1DM patients.

METHODS

Levels and activities of plasma MMP-2 and MMP-9 in patients with T1DM were investigated and compared to those of control individuals by enzyme-linked immunosorbent assay and zymography.

RESULTS

Circulatory levels and activities of MMP-2 and MMP-9 in patients with T1DM were significantly higher than those in control subjects.

CONCLUSIONS

MMP expression and activities are significantly increased in patients with T1DM. Our results not only document plasma MMPs levels and activities in the Taiwanese population (with a very low type 1 diabetic incidence), but also suggest that MMP expression and activity are elevated before the onset of complications in diabetic patients.

The differential inhibitory effects of genistein on the growth of cervical cancer cells in vitro

The biological effect of genistein on cervical cancer was studied on two cervical cancer cell lines with different cellular characteristics. Here we report that genistein exhibits inhibitory effects on the growth of HeLa and ME-180 cells. The IC50 was 35 microM and 60 microM for HeLa and ME-180 cells, respectively. ME-180 cells showed obvious G2/M arrest with genistein treatment while most of the HeLa cells were accumulated in S phase. The underlying molecular mechanism was further elucidated by apoptosis analysis and expression levels of cell cycle regulatory proteins. Treatment of the cell lines with genistein also resulted in suppression of invasion through a surrogate membrane in a dose-dependent manner, particularly the HeLa cells. While the underlying mechanism needs to be further studied, the higher suppressive effect on invasion of HeLa cells, an adenocarcinoma cell line, are noteworthy. This in vitro observation may have clinical implication to improve the treatment of cervical adenocarcinoma.

The presence of three isoflavonoid compounds in Psoralea corylifolia

The optimization of a high-performance liquid chromatographic method to determine three isoflavonoids (daidzein, genistein, and biochanin A) in the fruit of Psoralea corylifolia is developed and validated. Dried psoralea fruit powder is extracted with aqueous methanol followed by the hydrolysis of the analytes' conjugated glycosides with hydrochloric acid. The HPLC assay is performed on a reverse-phase C18 column with gradient elution using acetonitrile and 10% acetic acid as the mobile phase at a flow rate of 0.8 mL/min. Flavone is used as the internal standard and the substances are detected at 260 nm. Calibrations are linear (correlation coefficient > or = 0.995) for all three analytes. The limits of detection are 0.01 microg/mL for daidzein and genistein and 0.1 microg/mL for biochanin A. The overall intra- and interassay precision range from 2.5% to 4.9% and from 0.5% to 4.7%, respectively. The method proved to be sensitive, specific, accurate, and precise for the determination of daidzein, genistein, and biochanin A in Psoralea corylifolia.

Bax translocation to mitochondria subsequent to a rapid loss of mitochondrial membrane potential

Bax, a pro-apoptotic member of the Bcl-2 family, is a cytosolic protein that inserts into mitochondrial membranes upon induction of cell death. Using the green fluorescent protein fused to Bax (GFP-Bax) to quantitate mitochondrial binding in living cells we have investigated the cause of Bax association with mitochondria and the time course relative to endogenous and induced changes in mitochondrial membrane potential (DeltaPsi(m)). We have found that staurosporine (STS) induces a loss in DeltaPsi(m) before GFP-Bax translocation can be measured. The onset of the DeltaPsi(m) loss is followed by a rapid and complete collapse of DeltaPsi(m) which is followed by Bax association with mitochondria. The mitochondria uncoupler FCCP, in the presence of the F(1)-F(0) ATPase inhibitor oligomycin, can trigger Bax translocation to mitochondria suggesting that when ATP levels are maintained a collapse of DeltaPsi(m) induces Bax translocation. Neither FCCP nor oligomycin alone alters Bax location. Bax association with mitochondria is also triggered by inhibitors of the electron transport chain, antimycin and rotenone, compounds that collapse DeltaPsi(m) without inducing rapid ATP hydrolysis that typically occurs with uncouplers such as FCCP. Taken together, our results suggest that alterations in mitochondrial energization associated with apoptosis can initiate Bax docking to mitochondria.

Mitochondria in Ca2+ signaling and apoptosis

Cellular Ca2+ signals are crucial in the control of most physiological processes, cell injury and programmed cell death; mitochondria play a pivotal role in the regulation of such cytosolic Ca2+ ([Ca2+]c) signals. Mitochondria are endowed with multiple Ca2+ transport mechanisms by which they take up and release Ca2+ across their inner membrane. These transport processes function to regulate local and global [Ca2+]c, thereby regulating a number of Ca2+-sensitive cellular mechanisms. The permeability transition pore (PTP) forms the major Ca2+ efflux pathway from mitochondria. In addition, Ca2+ efflux from the mitochondrial matrix occurs by the reversal of the uniporter and through the inner membrane Na+/Ca2+ exchanger. During cellular Ca2+ overload, mitochondria take up [Ca2+]c, which, in turn, induces opening of PTP, disruption of mitochondrial membrane potential (delta(psi)m) and cell death. In apoptosis signaling, collapse of delta(psi)m and cytochrome c release from mitochondria occur followed by activation of caspases, DNA fragmentation, and cell death. Translocation of Bax, an apoptotic signaling protein from the cytosol to the mitochondrial membrane, is another step during this apoptosis-signaling pathway. The role of permeability transition in the context of cell death in relation to Bcl-2 family of proteins is discussed.

Joint vibration analysis protocol modification: adding mandibular excursive movements

This case study discusses the advantage of using both lateral and protrusive mandibular excursive movements to improve the accuracy of the joint vibration analysis rather than relying only on opening and closing movements of the mandible for analysis.

Conformation of the Bax C-terminus regulates subcellular location and cell death

Bax, a pro-apoptotic member of the Bcl-2 family, translocates from the cytosol to the mitochondria during programmed cell death. We report here that both gain-of-function and loss-of-function mutations can be achieved by altering a single amino acid in the Bax hydrophobic C-terminus. The properly mutated C-terminus of Bax can target a non-relevant protein to the mitochondria, showing that specific conformations of this domain alone allow mitochondrial docking. These data along with N-terminus epitope exposure experiments suggest that the C- and the N-termini interact and that upon triggering of apoptosis, Bax changes conformation, exposing these two domains to insert into the mitochondria and regulate the cell death machinery.

Bax in murine thymus is a soluble monomeric protein that displays differential detergent-induced conformations

Bcl-2, Bcl-XL, and Bax are members of the Bcl-2 family that play important roles in apoptosis regulation. These proteins are believed to be membrane-bound and to regulate apoptosis through formation of homo- and heterodimers. However, we recently found by subcellular fractionation that whereas Bcl-2 is predominantly a membrane protein as previously reported, Bax and a significant fraction of Bcl-XL are soluble in thymocyte and splenocyte extracts. In addition, we have demonstrated that the ability of Bax to form dimers appears to be a detergent-induced phenomenon that coincides with a detergent-induced conformational change. We have further investigated the tertiary and quaternary states of Bax in the presence of various detergents. Detergents such as Triton X-100 and Triton X-114 readily enable Bax hetero- and homodimerization. However, other detergents such as polydocanol, W-1, octyl glucoside, dodecyl maltoside, Tween 20, and sodium cholate allow varying degrees of Bax hetero- and homodimerization. Detergents such as 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid (Chaps) and Brij 35 allow neither hetero- nor homodimer formation. Immunoprecipitation analysis with the conformation-sensitive antibody uBax 6A7 revealed that whereas Triton X-100 readily exposes the N-terminal Bax epitope (amino acid 13-19), only limited exposure of the epitope occurs in Triton X-114, polydocanol, dodecyl maltoside, and sodium cholate, and no exposure of this epitope was observed in W-1, Chaps, octyl glucoside, Tween 20, and Brij 35. Moreover, we could not detect any proteins associated with the cytosolic form of Bax based on immunopurification of this protein. Sephacryl S-100 gel filtration chromatography analysis of the cytosolic Bax indicated that this protein is monomeric and displays an apparent molecular mass of 25 kDa. Induction of apo-ptosis which causes the insertion of the soluble form of Bax into membranes did not result in appreciable Bax/Bcl-XL, Bax/Bcl-2 or Bax/Bax dimer formation as determined by cross-linking studies. Further analysis of Bax after apoptosis induction by immunoprecipitation in the presence of Chaps also revealed no significant heterodimer formation. In conclusion, Bax displays several distinct states in different detergents that expose defined regions of the protein. In addition, these results suggest that mechanisms other than the simple dimerization among members of the Bcl-2 family may be required for the regulation of apoptosis.

The role of 2'-5' oligoadenylate-activated ribonuclease L in apoptosis

Apoptosis of viral infected cells appears to be one defense strategy to limit viral infection. Interferon can also confer viral resistance by the induction of the 2-5A system comprised of 2'-5' oligoadenylate synthetase (OAS), and RNase L. Since rRNA is degraded upon activation of RNase L and during apoptosis and since both of these processes serve antiviral functions, we examined the role RNase L may play in cell death. Inhibition of RNase L activity, by transfection with a dominant negative mutant, blocked staurosporine-induced apoptosis of NIH3T3 cells and SV40-transformed BALB/c cells. In addition, K562 cell lines expressing inactive RNase L were more resistant to apoptosis induced by decreased glutathione levels. Hydrogen peroxide-induced death of NIH3T3 cells did not occur by apoptosis and was not dependent upon active RNAse L. Apoptosis regulatory proteins of the Bcl-2 family did not exhibit altered expression levels in the absence of RNase L activity. RNase L is required for certain pathways of cell death and may help mediate viral-induced apoptosis.

MR findings of Werdnig-Hoffmann disease in two infants

We report two infants with Werdnig-Hoffmann disease diagnosed by means of spinal MR imaging, histopathologic examination of muscle biopsy specimens, cloned DNA analysis, electrophysiological examination, and clinical history. The MR findings were consistent with previous histopathologic reports.