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To analyze the gene involved in orchid floral development, a HD-Zip II gene PaHAT14, which specifically and highly expressed in perianth during early flower development was identified from Phalaenopsis. Transgenic Arabidopsis plants expressing 35S::PaHAT14 and 35S::PaHAT14+SRDX (fused with the repressor motif SRDX) exhibited similar altered phenotypes, including small leaves, early flowering, and bending petals with increased cuticle production. This suggests that PaHAT14 acts as a repressor. In contrast, transgenic Arabidopsis plants expressing 35S::PaHAT14+VP16 (fused with the activation domain VP16) exhibited curled leaves, late flowering, and folded petals with decreased cuticle production within hardly opened flowers. Additionally, the expression of the ERF gene DEWAX2, which negatively regulates cuticular wax biosynthesis, was down-regulated in 35S::PaHAT14 and 35S::PaHAT14+SRDX transgenic Arabidopsis, while it was up-regulated in 35S::PaHAT14+VP16 transgenic Arabidopsis. Furthermore, transient overexpression of PaHAT14 in Phalaenopsis petal/sepal increased cuticle deposition due to the down-regulation of PaERF105, a Phalaenopsis DEWAX2 orthologue. On the other hand, transient overexpression of PaERF105 decreased cuticle deposition, whereas cuticle deposition increased and the rate of epidermal water loss was reduced in PaERF105 VIGS Phalaenopsis flowers. Moreover, ectopic expression of PaERF105 not only produced phenotypes similar to those in 35S::PaHAT14+VP16 Arabidopsis but also compensated for the altered phenotypes observed in 35S::PaHAT14 and 35S::PaHAT14+SRDX Arabidopsis. These results suggest that PaHAT14 promotes cuticle deposition by negatively regulating downstream gene PaERF105 in orchid flowers., (© The Author(s) 2024. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site–for further information please contact journals.permissions@oup.com.)

Background: This nationwide prospective registry study investigated the real-world effectiveness, safety, and persistence of vedolizumab (VDZ) in inflammatory bowel disease (IBD) patients in Taiwan. Disease relapse rates after VDZ discontinuation due to reimbursement restriction were assessed., Methods: Data were collected prospectively (January 2018 to May 2020) from the Taiwan Society of IBD registry., Results: Overall, 274 patients (147 ulcerative colitis [UC] patients, 127 Crohn's disease [CD] patients) were included. Among them, 70.7% with UC and 50.4% with CD were biologic-naïve. At 1 year, 76.0%, 58.0%, 35.0%, and 62.2% of UC patients and 57.1%, 71.4%, 33.3%, and 30.0% of CD patients achieved clinical response, clinical remission, steroid-free remission, and mucosal healing, respectively. All patients underwent hepatitis B and tuberculosis screening before initiating biologics, and prophylaxis was recommended when necessary. One hepatitis B carrier, without antiviral prophylaxis due to economic barriers, had hepatitis B reactivation during steroid tapering and increasing azathioprine dosage, which was controlled with an antiviral agent. No tuberculosis reactivation was noted. At 12 months, non-reimbursement-related treatment persistence rates were 94.0% and 82.5% in UC and CD patients, respectively. Moreover, 75.3% of IBD patients discontinued VDZ due to mandatory drug holiday. Relapse rates after VDZ discontinuation at 6 and 12 months were 36.7% and 64.3% in CD patients and 42.9% and 52.4% in UC patients, respectively., Conclusions: The findings demonstrated VDZ effectiveness in IBD patients in Taiwan, with high treatment persistence rates and favorable safety profiles. A substantial IBD relapse rate was observed in patients who had mandatory drug holiday., (© The Author(s) 2023. Published by Oxford University Press on behalf of Crohn’s & Colitis Foundation. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

This study investigated the risk of post-COVID-19 conditions in older patients with COVID-19 compared to those with influenza, and how age impacts this relationship. Patients aged ≥65 years with COVID-19 or influenza were identified using the TriNetX network. The risk of post-COVID-19 conditions was compared between survivors of COVID-19 and influenza, followed by a comparison of post-COVID-19 conditions risk between patients aged 65-74 years and those aged over 75 years. Compared with influenza survivors, post-COVID-19 conditions were significantly more prevalent in patients with COVID-19 (hazard ratio [HR], 1.534; 95% confidence interval [CI]: 1.405-1.675). Specifically, COVID-19 survivors have a significantly higher risk of experiencing abnormal breathing (HR, 2.052; 95% CI: 1.757-2.397), fatigue (HR, 1.587; 95% CI: 1.322-1.905), anxiety/depression (HR, 1.587; 95% CI: 1.322-1.905), cognitive symptoms (HR, 1.667; 95% CI: 1.295-2.146) and cough (HR, 1.250; 95% CI: 1.006-1.553) compared with the influenza group. Contrastingly, no significant difference was observed in the risk of any post-COVID-19 condition between COVID-19 survivors aged 65-74 years and those aged over 75 years (HR, 0.994; 95% CI: 0.920-1.073). However, a lower incidence of cognitive symptoms was observed in patients aged 65-74 years compared to those aged ≥75 years (HR, 0.543; 95% CI: 0.445-0.661). In conclusion, compared with influenza, older patients have a higher risk of developing post-COVID-19 conditions after SARS-CoV-2 infection, and those aged over ≥75 years may have an increased risk of developing cognitive symptoms compared to those aged 65-74 years., (© The Author(s) 2023. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Men are more likely to develop benign prostatic hyperplasia (BPH) and gout as they age. However, the role of alpha-1-adrenergic antagonists, the medication for BPH, in the development of gout is uncertain., Objective: To investigate the effect of alpha-1-adrenergic antagonist use on the risk of developing gout in BPH patients., Methods: Data of patients with newly diagnosed BPH were retrieved from Taiwan's 2000-2013 National Health Insurance Research Database (total number: 15,390 patients; 7,695 patients in each cohort). Propensity score matching was conducted according to age, comorbidities, medication history for cohorts that received or did not receive alpha-1-adrenergic antagonists. Hazard ratios (HRs) were assessed for gout development using Cox proportional hazards regression models., Results: Use of alpha-1-adrenergic antagonists was not associated with gout development in BPH patients (HR = 0.92; 95% confidence interval [CI], 0.78-1.10; P = 0.35). However, after stratification according to the average number of days of alpha-1-adrenergic antagonist use per year, patients with an average of >300 days had a significantly higher risk of gout development than patients who did not receive alpha-1-adrenergic antagonists (adjusted HR = 1.57; 95% CI, 1.25-1.97; P < 0.001). Patients with more days of medication use per year had a higher risk of gout development than those with fewer days of medication use (P < 0.001)., Conclusion: Patients who received more doses of alpha-1-adrenergic antagonists per year had a higher risk of developing gout. A causal proof of the role of alpha-1-adrenergic antagonists use in gout development should be analysed in future studies designed as double blind randomized controlled trials., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: We hypothesized that renin-angiotensin system (RAS) blockers have systemic protective effects beyond the respiratory tract and could reduce the risk of viral infections., Methods: We used the National Health Insurance Research Database and identified 2 study cohorts: the angiotensin receptor blocker (ARB) cohort and angiotensin-converting enzyme inhibitor (ACEI) cohort. Propensity score matching was applied at a 1:1 ratio by all associated variables to select 2 independent control cohorts for the ARB and ACEI cohorts. A Cox proportional hazards model was applied to assess the end outcome of viral infection., Results: The number of ARB and ACEI users was 20 207 and 18 029, respectively. The median age of ARB users and nonusers was 53.7 and 53.8 years, respectively. The median follow-up duration of ARB users and nonusers was 7.96 and 7.08 years; the median follow-up duration of ACEI users and nonusers was 8.70 and 8.98 years, respectively. The incidence rates of viral infections in ARB users and nonusers were 4.95 and 8.59 per 1000 person-years, respectively, and ARB users had a lower risk of viral infection than nonusers (adjusted hazard ratio [aHR], 0.53 [95% confidence interval {CI}, .48-.58]). The incidence rates of viral infections in ACEI users and nonusers were 6.10 per 1000 person-years and 7.72 per 1000 person-years, respectively, and ACEI users had a lower risk of viral infection than nonusers (aHR, 0.81 [95% CI, .74-.88])., Conclusions: Hypertensive patients using either ARBs or ACEIs exhibit a lower risk of viral infection than nonusers., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Programmed death-ligand 1 (PD-L1) expression is associated with clinical outcomes of epidermal growth factor receptor (EGFR) mutant lung adenocarcinoma (ADC) treated with tyrosine kinase inhibitors (TKIs). However, whether PD-L1 expression plays a role in anaplastic lymphoma kinase (ALK)-positive lung ADC is unknown. We aimed to evaluate the impact of PD-L1 in patients with ALK-positive lung ADC receiving crizotinib., Materials and Methods: PD-L1 expression was identified by immunohistochemistry (IHC). Reverse transcriptase-polymerase chain reaction was used for ALK variant detection, and immunofluorescence-based multiplex staining was applied for exploring immune cells in tumor microenvironments., Results: A total of 78 patients with ALK-positive advanced ADC were enrolled in our study, of whom 52 received crizotinib. Compared with EGFR/ALK wild-type tumors, PD-L1 expression was lower in ALK-positive ADC. ALK fusion variants were identified in 32 patients, and those with variant 3 and 5 (short variants) had higher PD-L1 expression than those with other variants. The crizotinib objective response rate (ORR) and progression-free survival (PFS) was better in tumors with negative PD-L1 expression (ORR/PFS in PD-L1 0% vs. 1%-49% vs. 50%-100%: 60.7%/11.8 months vs. 38.5%/6.5 months vs. 36.4%/4.0 months, p = .007/.022). The multivariate Cox proportional hazards model revealed that PD-L1 0% (vs. ≥1%) was an independent factor for longer PFS (adjusted hazard ratio 0.322, 95% confidence interval 0.160-0.650, p = .002). Multiplex IHC in three cases showed a varied extent of immune cell infiltrations in tumors with different PD-L1 expression., Conclusion: Positive PD-L1 expression was associated with unfavorable clinical outcomes in patients with ALK-positive lung ADC receiving crizotinib., Implications for Practice: Not all lung adenocarcinoma with sensitizing driver mutations experienced durable responses to small-molecule tyrosine kinase inhibitors (TKIs). Similar to the negative impact of programmed death-ligand 1 (PD-L1) in epidermal growth factor receptor mutant tumors treated with TKIs, this study demonstrated that positive PD-L1 expression was also associated with worse response rate and shorter progression-free survival of anaplastic lymphoma kinase (ALK)-positive adenocarcinoma treated with crizotinib. Among different ALK fusion partners, tumors with short variants (V3 and V5) had higher PD-L1 compared with long variants (V1, V2, and V6). Testing PD-L1 before initiating crizotinib for ALK-positive lung cancer could be a simple method to provide important prognostic information., (© AlphaMed Press 2020.)

Background: Cancer-related fatigue (CRF) is an emerging clinical issue, although its prevalence and impact on quality of life (QOL) in cancer patients in Taiwan remain unclear. The present nationwide cross-sectional study was conducted to provide a thorough overview of the prevalence, related factors and impact of CRF in Taiwan., Methods: In this multi-center survey, data were collected using the International Classification of Diseases 10th Revision (ICD-10) Fatigue evaluation, Brief Fatigue Inventory-Taiwan (BFI-T), the Chinese version of the Symptom Distressed Scale and a fatigue experience survey. Logistic regression was used to determine the correlations between fatigue characteristics and the factors studied., Results: A total of 1207 cancer patients were recruited from 23 hospitals in Taiwan. Fatigue was the most distressing symptom in Taiwanese cancer patients. The distress score was higher if CRF was diagnosed using ICD-10 compared with BFI-T. Rest and nutritional supplementation were the most common non-pharmacological treatments; blood transfusion was the most common pharmacological treatment. There were 45% of patients reported not receiving a timely intervention for fatigue., Conclusions: Fatigue is the most bothersome symptom reported by Taiwanese cancer patients. Caregivers should be aware of the impact of CRF on QOL in cancer patients, constantly measure the severity of fatigue and provide appropriate interventions., (© The Author(s) 2020. Published by Oxford University Press.)

Myeloid lineage cells present in human peripheral blood include dendritic cells (DC) and monocytes. The DC are identified phenotypically as HLA-DR + cells that lack major cell surface lineage markers for T cells (CD3), B cells (CD19, CD20), NK cells (CD56), red blood cells (CD235a), hematopoietic stem cells (CD34), and Mo that express CD14. Both DC and Mo can be phenotypically divided into subsets. DC are divided into plasmacytoid DC, which are CD11c - , CD304 + , CD85g + , and myeloid DC that are CD11c + . The CD11c + DC are readily classified as CD1c + DC and CD141 + DC. Monocytes are broadly divided into the CD14 + CD16 - (classical) and CD14 dim CD16 + subsets (nonclassical). A population of myeloid-derived cells that have DC characteristics, that is, HLA-DR + and lacking lineage markers including CD14, but express CD16 are generally clustered with CD14 dim CD16 + monocytes. We used high-dimensional clustering analyses of fluorescence and mass cytometry data, to delineate CD14 + monocytes, CD14 dim CD16 + monocytes (CD16 + Mo), and CD14 - CD16 + DC (CD16 + DC). We sought to identify the functional and kinetic relationship of CD16 + DC to CD16 + Mo. We demonstrate that differentiation of CD16 + DC and CD16 + Mo during activation with IFNγ in vitro and as a result of an allo-hematopoietic cell transplant (HCT) in vivo resulted in distinct populations. Recovery of blood CD16 + DC in both auto- and allo-(HCT) patients after myeloablative conditioning showed similar reconstitution and activation kinetics to CD16 + Mo. Finally, we show that expression of the cell surface markers CD300c, CCR5, and CLEC5a can distinguish the cell populations phenotypically paving the way for functional differentiation as new reagents become available., (©2019 Society for Leukocyte Biology.)

Background: Renal tubulointerstitial lesions (TILs), a key pathological hallmark for chronic kidney disease to progress to end-stage renal disease, feature renal tubular atrophy, interstitial mononuclear leukocyte infiltration and fibrosis in the kidney. Our study tested the renoprotective and therapeutic effects of compound K (CK), as described in our US patent (US7932057B2), on renal TILs using a mouse unilateral ureteral obstruction (UUO) model., Methods: Renal pathology was performed and renal draining lymph nodes were subjected to flow cytometry analysis. Mechanism-based experiments included the analysis of mitochondrial dysfunction, a model of tubular epithelial cells (TECs) under mechanically induced constant pressure (MICP) and tandem mass tags (TMT)-based proteomics analysis., Results: Administration of CK ameliorated renal TILs by reducing urine levels of proinflammatory cytokines, and preventing mononuclear leukocyte infiltration and fibrosis in the kidney. The beneficial effects clearly correlated with its inhibition of: (i) NF-κB-associated priming and the mitochondria-associated activating signals of the NLRP3 inflammasome; (ii) STAT3 signalling, which in part prevents NLRP3 inflammasome activation; and (iii) the TGF-β-dependent Smad2/Smad3 fibrotic pathway, in renal tissues, renal TECs under MICP and/or activated macrophages, the latter as a major inflammatory player contributing to renal TILs. Meanwhile, TMT-based proteomics analysis revealed downregulated renal NLRP3 inflammasome activation-associated signalling pathways in CK-treated UUO mice., Conclusions: The present study, for the first time, presents the potent renoprotective and therapeutic effects of CK on renal TILs by targeting the NLRP3 inflammasome and STAT3 signalling., (© The Author(s) 2019. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Aims: This study investigated whether patients with alcoholic cirrhosis have a high risk of hemorrhagic stroke., Methods: In this study, 17,094 patients diagnosed with cirrhosis between 2000 and 2010 were identified using the Taiwan National Health Insurance claims data. Identified patients were randomly selected and propensity score matched with individuals without cirrhosis according to age, sex, comorbidities and index year., Results: The overall incidence rate of stroke was 4.41 and 12.1 per 1000 person-years in the chronic liver disease and cirrhosis (CLDC) with hepatitis B virus (HBV) or hepatitis C virus (HCV) cohort and the alcoholic CLDC cohort, respectively. The alcoholic CLDC cohort exhibited a 4.53-fold higher risk of hemorrhagic stroke (adjusted subhazard ratio [aSHR] = 4.53, 95% confidence interval [CI] = 3.05-6.71) than did the non-CLDC cohort, and the CLDC with HBV or HCV cohort exhibited a 1.40-fold higher risk of hemorrhagic stroke (aSHR = 1.40, 95% CI = 1.10-1.78) than did the non-CLDC cohort. The alcoholic CLDC cohort and the CLDC with HBV or HCV cohort showed an aSHR of 1.80 (95% CI = 1.36-2.40) and 0.95 (95% CI = 0.83-1.07) for ischemic stroke, respectively, compared with the non-CLDC cohort., Conclusion: Alcoholic patients with CLDC had a higher risk of hemorrhagic stroke compared with non-alcoholic patients with CLDC and patients without CLDC., (© The Author(s) 2019. Medical Council on Alcohol and Oxford University Press. All rights reserved.)

Background: Humans have 4 million exocrine sweat glands, which can be classified into two types: eccrine and apocrine glands. Sweat secretion, a constitutive feature, is directly involved in thermoregulation and metabolism, and is regulated by both the central nervous system (CNS) and autonomic nervous system (ANS)., Objectives: To explore how sweat secretion is controlled by both the CNS and the ANS and the mechanisms behind the neural control of sweat secretion., Methods: We conducted a literature search on PubMed for reports in English from 1 January 1950 to 31 December 2016., Results and Conclusions: Acetylcholine acts as a potent stimulator for sweat secretion, which is released by sympathetic nerves. β-adrenoceptors are found in adipocytes as well as apocrine glands, and these receptors may mediate lipid secretion from apocrine glands for sweat secretion. The activation of β-adrenoceptors could increase sweat secretion through opening of Ca 2+ channels to elevate intracellular Ca 2+ concentration. Ca 2+ and cyclic adenosine monophosphate play a part in the secretion of lipids and proteins from apocrine glands for sweat secretion. The translocation of aquaporin 5 plays an important role in sweat secretion from eccrine glands. Dysfunction of the ANS, especially the sympathetic nervous system, may cause sweating disorders, such as hypohidrosis and hyperhidrosis., (© 2017 British Association of Dermatologists.)

Objectives: The aim of the study is to demonstrate the relationship between clinicopathological variables and occult lymph node metastasis in resected lung adenocarcinoma., Methods: The clinicopathological characteristics of 471 patients with clinical N2-negative status undergoing resection for lung adenocarcinoma of 3 cm or smaller at Taipei Veterans General Hospital between 2004 and 2012 were retrospectively reviewed. The association between clinicopathological variables and lymph node metastasis was analysed by univariate and multivariate logistic regression., Results: Among the 471 patients, there were 386 (82.0%) patients with pathological N0 status, 35 (7.4%) with pathological N1 status and 50 (10.6%) with pathological N2 status. Greater tumour size (P = 0.002), presence of a micropapillary pattern (P < 0.001), presence of a solid pattern (P < 0.001) and predominant pattern group (micropapillary/solid predominant) (P = 0.001) were significantly associated with higher percentage of occult N2 lymph node metastasis. In multivariate analysis, greater tumour size (P = 0.008), presence of micropapillary pattern (P < 0.001) and presence of solid pattern (P = 0.001) were significant predictors of occult N2 lymph node metastasis in tumours of 3 cm or smaller. When histological pattern was entered as the predominant pattern in multivariate analysis, micropapillary/solid predominant pattern (P = 0.005) was also a significant predictor of occult N2 lymph node metastasis., Conclusions: The presence of micropapillary or solid pattern, as well as micropapillary/solid predominant pattern, is significantly associated with occult N2 lymph node metastasis in lung adenocarcinoma. Radical mediastinal lymph node dissection may help to identify occult lymph node metastasis in these patients., (© The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

This study focused on the investigation of the effects of the PI motif and C-terminus of the Oncidium Gower Ramsey MADS box gene 8 (OMADS8), a PISTILLATA (PI) ortholog, on floral organ formation. 35S::OMADS8 completely rescued and 35S::OMADS8-PI (with the PI motif deleted) partially rescued petal/stamen formation, whereas these deficiencies were not rescued by 35S::OMADS8-C (C-terminal 29 amino acids deleted) in pi-1 mutants. OMADS8 could interact with Arabidopsis APETALA3 (AP3) and enter the nucleus. The nuclear entry efficiency was reduced for OMADS8-PI/AP3 and OMADS8-C/AP3. OMADS8 could also interact with OMADS5/OMADS9 (the Oncidium AP3 ortholog) and enter the nucleus with an efficiency only slightly affected by the deletion of the C-terminal sequence or PI motif. However, the stability of the OMADS8/OMADS5 and OMADS8/OMADS9 complexes was significantly reduced by deletion of the C-terminal sequence or PI motif. Further analysis indicated that the expression of genes downstream of AP3/PI (BNQ1/BNQ2/GNC/At4g30270) was compensated by 35S::OMADS8 and 35S::OMADS8-PI to a level similar to wild-type plants but was not affected by 35S::OMADS8-C in the pi-1 mutants. A similar FRET (fluorescence resonance energy transfer) efficiency was observed for Arabidopsis AGAMOUS (AG) and the Oncidium AG ortholog OMADS4 for OMADS8, OMADS8-PI and OMADS8-C. These results indicated that the OMADS8 PI motif and C-terminus were valuable for the interaction of OMADS8 with the AP3 orthologs to form higher order heterotetrameric complexes that regulated petal/stamen formation in both Oncidium orchids and transgenic Arabidopsis. However, the C-terminal sequence and PI motif were dispensable for the interaction of OMADS8 with the AG orthologs., (© The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objectives: Few Asian studies have evaluated the risks of deep vein thrombosis (DVT) and pulmonary thromboembolism (PTE) in patients with SSc. We conducted a nationwide population-based cohort study to evaluate how SSc affected the incidence of DVT and PTE in Taiwan., Methods: We identified patients with an SSc diagnosis in Taiwan between 1998 and 2010 using the Catastrophic Illness Patient Database and the National Health Insurance Research Database. Each SSc patient was frequency matched to four control patients based on age, sex and index year and all patients were observed from the index date until the appearance of a DVT or PTE event or 31 December 2010. We calculated the hazard ratios and 95% CIs of DVT and PTE in the SSc and comparison cohorts using the Cox proportional hazards regression model., Results: We observed 1895 SSc patients and 7580 control patients for ∼10,128 and 46,488 person-years, respectively. The mean ages of the SSc and comparison cohorts were 50.3 and 49.9 years, respectively. After adjusting for age, sex and co-morbidities, the risks of DVT and PTE among the SSc patients were 10.5- and 7.00-fold higher than those of the control patients. The probability of developing DVT and PTE increased in the years following the SSc diagnosis., Conclusion: SSc patients exhibited a significantly higher risk of developing DVT and PTE compared with the general population. Thus multidisciplinary teams should guide the assessment, treatment and holistic care of SSc patients., (© The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Objectives: Although significant improvement in myasthenic symptoms has been reported following the removal of thymolipomas, information on surgical outcomes among patients with thymolipomatous myasthenia gravis (MG) is limited., Methods: This was a retrospective review of patients who underwent extended thymectomy for treatment of MG., Results: From 1995 to 2010, 267 patients with MG underwent extended thymectomy, including 104 with thymomatous MG, 151 with non-thymomatous MG and 12 (4.4%) with thymolipoma. The mean duration of myasthenic symptoms before surgery was greatest in the thymolipomatous group (P < 0.001). The lowest mean age (36.1 years old, P < 0.001) and the lowest preoperative serum anti-acetylcholine receptor antibody titre (P = 0.015) occurred in the non-thymomatous group. More thymic and adipose tissue was removed from the thymolipomatous group compared with the non-thymomatous group (P < 0.001). Regarding surgical outcomes, the rate of stable remission was higher in the non-thymomatous (42.3%) and thymolipomatous (41.7%) groups compared with the thymomatous group (28.8%, P = 0.029). No instances of postoperative exacerbation of MG or tumour recurrence were noted during the postoperative follow-up of patients treated for thymolipoma., Conclusions: Our results suggest that patients with myasthenia thymolipomatous have surgical outcomes similar to those of patients with non-thymomatous MG and have a mean age at the time of surgery similar to that of patients with thymomatous MG.

ANTHER INDEHISCENCE FACTOR (AIF), a NAC-like gene, was identified in Arabidopsis. In AIF:GUS flowers, β-glucuronidase (GUS) activity was detected in the anther, the upper parts of the filaments, and in the pollen of stage 7-9 young flower buds; GUS activity was reduced in mature flowers. Yellow fluorescent protein (YFP)+AIF-C fusion proteins, which lacked a transmembrane domain, accumulated in the nuclei of the Arabidopsis cells, whereas the YFP+AIF fusion proteins accumulated in the membrane and were absent in the nuclei. Further detection of a cleaved AIF protein in flowers revealed that AIF needs to be processed and released from the endoplasmic reticulum in order to function. The ectopic expression of AIF-C caused a male-sterile phenotype with indehiscent anthers throughout flower development in Arabidopsis. The presence of a repressor domain in AIF and the similar phenotype of indehiscent anthers in AIF-C+SRDX plants suggest that AIF acts as a repressor. The defect in anther dehiscence was due to the down-regulation of genes that participate in jasmonic acid (JA) biosynthesis, such as DAD1/AOS/AOC3/OPR3/OPCL1. The external application of JA rescued the anther indehiscence in AIF-C and AIF-C+SRDX flowers. In AIF-C+VP16 plants, which are transgenic dominant-negative mutants in which AIF is converted to a potent activator via fusion to a VP16-AD motif, the anther dehiscence was promoted, and the expression of DAD1/AOS/AOC3/OPR3/OPCL1 was up-regulated. Furthermore, the suppression of AIF through an antisense strategy resulted in a mutant phenotype similar to that observed in the AIF-C+VP16 flowers. The present data suggest a role for AIF in controlling anther dehiscence by suppressing the expression of JA biosynthesis genes in Arabidopsis.

Objectives: While neoadjuvant chemoradiation followed by surgery has been shown to improve the survival of patients with locally advanced oesophageal cancer, it is not known whether neoadjuvant chemoradiation has a beneficial or harmful effect on the non-responders. We aimed to compare the outcomes among neoadjuvant chemoradiation responders, non-responders and patients receiving primary oesophagectomies for resectable locally advanced oesophageal squamous cell carcinoma., Methods: Eighty-four non-T1-2N0 oesophageal squamous cell carcinoma patients were included. Thirty-eight patients received primary resection and 46 patients received neoadjuvant chemoradiation. The overall survival of chemoradiation responders (<50% residual tumour), non-responders (>50% residual tumour and those who shifted to definitive chemoradiation instead of surgery due to tumour progression) and patients receiving primary resection were compared. Clinical parameters were also compared between responders and non-responders., Results: There was no overall difference in survival between neoadjuvant chemoradiation and primary resection groups (2-year overall survival rates: 45.6 vs 54.3%, P = 0.442). In patients receiving neoadjuvant chemoradiation followed by surgery, pathological responders had significantly higher 2-year overall survival rates than non-responders (64.5 vs 38.9%, P = 0.043). While the pathological responders had the highest survival rate, clinicopathological non-responders (pathological non-responders and patients with tumour progression during the neoadjuvant chemoradiation period) demonstrated significantly worse outcomes than those receiving primary resection (32.0 vs 54.3%, P = 0.036). However, none of the clinical parameters, including blood profiles, images and baseline tumour characteristics, predicted the response to chemoradiation before treatment., Conclusions: Neoadjuvant chemoradiation non-responders demonstrated no benefit and an even worse outcome compared with those receiving primary resection for locally advanced oesophageal squamous cell carcinoma. However, no significant clinical parameters could be implemented in the clinics to predict the response to neoadjuvant chemoradiation before treatment.

A small, specialised amplifier using commercial integrated circuits (ICs) was developed to measure radiation dose and quality in real time using a microdosimetric ion chamber and the variance method. The charges from a microdosimetric ion chamber, operated in the current mode, were repeatedly collected for a fixed period of time for 20 cycles of 100 integrations, and processed by this specialised amplifier to produce signal pulse heights between 0 and 10 V. These signals were recorded by a multi-channel analyser coupled to a computer. FORTRAN programs were written to calculate the dose and dose variance. The dose variance produced in the ion chamber is a microdosimetric measure of radiation quality. Benchmark measurements of different brands of ICs were conducted. Results demonstrate that this specialised amplifier is capable of distinguishing differences of radiation quality in various high-dose-rate radiation fields including X rays, gamma rays and mixed neutron-gamma radiation from the research reactor at Texas A&M University Nuclear Science Center.

Objective: We sought to determine whether Charlson comorbidity index (CCI) or Kaplan-Feinstein index (KFI) is a better predictor of prognosis in patients with stage I NSCLC after surgical resection., Methods: A retrospective study of medical records of 426 patients with stage I lung cancer having complete surgical resection from 1995 to 2000 was performed. Data collected included age, gender, smoking history, resection type, pleural invasion status, and tumor type and size. Comorbidity score was determined using Charlson comorbidity index and Kaplan-Feinstein index. Both univariate and multivariate analyses were used to evaluate prognostic factors., Results: Three hundred and twenty-eight male (76.99%) and 98 female (23.01%) patients had a mean age of 67.07 years (range 19-88 years). Median duration of follow-up was 60.32 months. Total follow-up rate was 95.1%. Distribution of CCI score was: 0, 236 (55.40%); 1, 112 (26.29%); >or=2, 78 (18.31%). Overall KFI score was: none, 247 (57.98%); mild, 126 (29.58%); moderate, 43 (10.09%); and severe, 10 (2.35%). In univariate analyses, patients aged>or=65 years, male, smokers, CCI score>or=2, extensive resection and pathological stage IB cancer had poorer 5-year survival. In multivariate logistic regression analysis, age>or=65 years, pneumonectomy, CCI score>or=2, and stage IB cancer were independent prognostic factors for poorer 5-year survival., Conclusions: Patients with CCI>or=2 had higher perioperative mortality and death from non-cancer causes after surgery compared to patients with CCI<2. However, KFI score had no impact on operative mortality and non-cancer death during follow-up.

Background and Purpose: Virtual reality (VR) creates an exercise environment in which the intensity of practice and positive feedback can be systematically manipulated in various contexts. The purpose of this study was to investigate the training effects of a VR intervention on reaching behaviors in children with cerebral palsy (CP)., Participants: Four children with spastic CP were recruited., Method: A single-subject design (A-B with follow-up) was used. All children were evaluated with 3 baseline, 4 intervention, and 2 follow-up measures. A 4-week individualized VR training program (2 hours per week) with 2 VR systems was applied to all children. The outcome measures included 4 kinematic parameters (movement time, path length, peak velocity, and number of movement units) for mail-delivery activities in 3 directions (neutral, outward, and inward) and the Fine Motor Domain of the Peabody Developmental Motor Scales-Second Edition (PDMS-2). Visual inspection and the 2-standard-deviation-band method were used to compare the outcome measures., Results: Three children who had normal cognition showed improvements in some aspects of reaching kinematics, and 2 children's change scores on the PDMS-2 reached the minimal detectable change during the intervention. The improvements in kinematics were partially maintained during follow-up., Discussion and Conclusion: A 4-week individualized VR training program appeared to improve the quality of reaching in children with CP, especially in children with normal cognition and good cooperation. The training effects were retained in some children after the intervention.

Background and Purpose: Virtual reality (VR) technology has gained importance in many areas of medicine. Knowledge concerning the application and the influence of VR-enhanced exercise programs is limited for patients receiving coronary artery bypass grafting. The purpose of this study was to evaluate the effect of a virtual "country walk" on the number of sessions necessary to reach cardiac rehabilitation goals in patients undergoing coronary artery bypass grafting., Subjects: Twenty subjects who were seen for cardiac rehabilitation between January and June 2004 comprised the study sample., Methods: The protocol for this study included an initial maximum graded exercise tolerance test, given to determine the subsequent training goals for the subject, followed by biweekly submaximal endurance training sessions. All subjects were assigned by lot to 1 of 2 submaximal endurance training programs, one (group 2) with and the other (group 1) without the added VR environment. In all other respects, the 2 programs were identical. Each training session lasted for 30 minutes and was carried out twice per week for about 3 months. The primary outcome measures were maximum load during the work sessions, target oxygen consumption, target heart rate (beats per minute), and number of training sessions required to reach rehabilitation goals., Results: By the end of 20 training sessions, only 4 of the 10 control subjects had reached the heart rate target goal of 85% their maximum heart rate. In contrast, 9 of the 10 subjects in the VR program had attained this goal by 9 or fewer training sessions. When target metabolic cost (75% peak oxygen consumption) was used as the training goal, all 10 subjects in the VR program had reached this target after 2 training sessions (or, in some cases, 1 training session), but not until training session 15 did a cumulative number of 9 control subjects reach this goal., Discussion and Conclusion: These study outcomes clearly support the notion that incorporating a VR environment into cardiac rehabilitation programs will accelerate maximum recovery of patients' cardiovascular function.

Thymectomy is considered a therapeutic option for patients with myasthenia gravis. A myasthenic patient who has not received any treatment for years and shows no signs or symptoms of the disease after operation is still susceptible to a recurrence of myasthenic symptoms. To investigate which factors are related to relapse of symptoms in patients having thymectomy, we conduct a retrospective review in the patients who had experienced complete remission after thymectomy. Complete remission was achieved in 92 of 154 patients who received extended transsternal thymectomy for myasthenia gravis. Among these 92 patients, 20 patients had relapse of symptoms and needed medication again after complete remission was achieved (21.7%). Ten of 22 patients in the thymomatous group had relapse of symptom after complete remission was achieved, while only 10 of 70 patients in the nonthymomatous group had relapse of symptom (P=0.006). Multivariate Cox regression analysis revealed that thymoma was an independent factor for the development of relapse of symptoms. In conclusion, thymoma is an adverse prognostic factor for the MG patients who have experienced complete remission after thymectomy. The patients with thymoma had a greater possibility to develop relapse of symptoms than the patients without thymoma.

The functional significance of amino acid residues Lys-265, Asp-270, Lys-277, Asp-288, Asp-347, Glu-349, and Arg-351 of Bacillus kaustophilus leucine aminopeptidase was explored by site-directed mutagenesis. Variants with an apparent molecular mass of approximately 54 kDa were overexpressed in Escherichia coli and purified to homogeneity by nickel-chelate chromatography. The purified mutant enzymes had no LAP activity, implying that these residues are important for the catalytic reaction of the enzyme.

Background: This study examines the usefulness of thallium-201 single photon emission computed tomography ((201)Tl SPECT) in differentiating pulmonary malignancies from benign lesions by using dual phase (201)Tl scintigraphy., Methods: One hundred and six patients with thoracic lesions and confirmed diagnoses were assessed by (201)Tl chest SPECT examinations; of these 106 enrolled thoracic lesions, 59 were malignancies and 47 were benign lesions. Dual phase (201)Tl SPECT was performed with an early image acquired at 10-20 min and a delayed image at 2-3 h after intravenous injection of 2-3 mCi of (201)Tl. The results of (201)Tl SPECT images were classified as either malignant or benign lesions by visual interpretation: the lesion was interpreted as positive for malignancy if the uptake of (201)Tl in the lung lesion in the delayed phase was increased or persistent as compared with that in the early phase image; otherwise, it was considered as a benign lesion. Simultaneously, the traditional method of retention index (RI) was also calculated to help in the differential diagnosis of pulmonary lesions. Then, both methods of dual phase (201)Tl SPECT, visual reading and traditional RI, were compared to differentiate pulmonary malignancies from benign lesions., Results: Analyzing the image results, we found that dual phase (201)Tl SPECT could differentiate pulmonary malignancies from benign lesions with a sensitivity of 83%, a specificity of 91% and an accuracy of 87%. Moreover, by using the traditional RI method of (201)Tl SPECT, it could differentiate pulmonary malignancy from benign lesions with a sensitivity of 79.3%, a specificity of 80.8% and an accuracy of 80%., Conclusions: We conclude that using dual phase (201)Tl SPECT with visual interpretation is a simpler and potentially more effective method for differentiating pulmonary malignancies from benign lesions, with results compatible with the traditional RI method of (201)Tl SPECT.

Bacillus stearothermophilus leucine aminopeptidase II (LAPII) was fused at its C-terminal end with the raw-starch-binding domain of Bacillus sp. strain TS-23 alpha-amylase. The chimeric enzyme (LAPsbd), with an apparent molecular mass of approximately 61 kDa, was overexpressed in IPTG-induced Escherichia coli cells and purified to homogeneity by nickel-chelate chromatography. The purified enzyme retained LAP activity and adsorbed raw starch. LAPsbd was stable at 70 degrees C for 10 min, while the activity of wild-type enzyme was completely abolished under the same environmental condition. Compared with the wild-type enzyme, the twofold increase in the catalytic efficiency for LAPsbd was due to a 218% increase in the k(cat) value.

Objective: The number of totally removed lymph nodes during thoracotomy was used alternatively to represent the quality of lymphadenectomy in patients with pathologic stage I non-small cell lung cancer (NSCLC). We combined this new parameter with other well-established prognostic factors and performed multivariate survival analyses to validate its usage as a stage control., Methods: Three hundred and twenty-one patients who underwent complete surgical resection for stage I NSCLC were reviewed retrospectively. Aside from the number of lymph nodes removed during thoracotomy, other well-known clinical and histopathological factors were also included as possible prognostic factors for analysis. Two survival analyses, overall death and cancer-related death as study end-point, were performed, using the Kaplan-Meier method and multivariable Cox's proportional hazard regression analysis. Stepwise method of variable selection was employed to choose the 'best' Cox proportional hazard model in each survival analysis., Results: The overall 5- and 10-year survival rates were 48 and 35%, and the cancer-related 5- and 10-year survival rate was 63.3 and 58.3%, respectively. The number of totally removed lymph nodes during thoracotomy, tumor size and smoking history in multivariable analysis significantly affected both overall and cancer-related survival rates. Cell type of adenocarcinoma or large cell carcinoma was associated with a worse cancer-related survival compared with other histological types., Conclusions: The quality of lymphadenectomy, represented quantitatively by the number of totally removed lymph nodes during thoracotomy, may impact on a more accurate tumor stage, and will affect the survival rate for patients with stage I NSCLC as well as other well known clinical and histopathological factors.

Objective: The use of a T-tube to manage complex laryngotracheal lesions, such as tracheal stenosis, tracheomalacia and tracheal injury, has previously been reported by other surgeons in the past. However, further validation of clinical details, including operative management and postoperative care, is needed., Methods: From January 1991 to May 2000, 53 patients, including 24 with post-tracheostomy stenosis, received 55 silicone T-tubes for transient or permanent stenting of the airway. There were 20 patients for subglottic stenosis; eight for long segment tracheostensis; seven with tracheal stenosis for severe cervicomediastinal fibrosis not amenable for reconstruction; six for complex tracheal injury; four for glottic injury; two each for tracheomalacia, failed tracheal surgery and tuberculotic tracheostenosis; and one each for tracheo-esophageal fistula and necrotizing tracheitis. We retrospectively analyzed these patients., Results: Thirty-eight out of 53 patients (71.8%) with T-tube stenting from 3 to 15 months was considered successful. Fifteen patients' operations failed due to patients' underlining diseases, previous intractable pulmonary infection, poor cognition and/or inadequate tube position. After removal of the tube, three patients (10.7%) developed partial airway obstruction with mild subglottic granulation tissue, which was resolved by carbon dioxide laser therapy. Two patients (7.1%) with prolonged tracheocutaneous fistula were conservatively treated by silver nitrate., Conclusion: Silicone T-tube can effectively resolve the complex laryngotracheal lesions with limited complications. Concurrent cardiopulmonary diseases and intractable infection were the two major causes for failure after the T-tube reconstruction.

Corynebacterium glutamicum 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthase is sensitive to feedback inhibition by tyrosine. One feedback-insensitive mutant was obtained by in vitro chemical mutagenesis and the mutation was identified as a C-->G mutation at nucleotide 560 causing a Ser(187) to Cys(187) substitution. Replacing Ser(187) with cysteine, tyrosine or phenylalanine by site-directed mutagenesis not only reduced the enzymatic activity but also relieved its feedback inhibition by tyrosine, while Ser(187)Ala exhibited a comparable activity to that of wild-type enzyme and sensitized to allosteric regulation. The His(6)-tagged enzymes were expressed in Escherichia coli and purified to homogeneity by immobilized nickel-ion affinity chromatography. Kinetic analysis showed that tyrosine is a competitive inhibitor of phosphoenol pyruvate, one of the precursors for DAHP biosynthesis.

Each of the six oxidative-sensitive methionine residues in Trigonopsis variabilis D-amino acid oxidase (DAAO) was changed to leucine by site-directed mutagenesis. The wild-type and mutant enzymes with an apparent molecular mass of about 39.3 kDa were expressed in Escherichia coli. The specific activity of four mutant DAAOs (Met(104)Leu, Met(226)Leu, Met(245)Leu, and Met(339)Leu) was decreased by more than 96%, while Met(156)Leu and Met(209)Leu showed about 23% and 96% higher activity, respectively, than the wild-type enzyme. The kinetic parameters of the two more active enzymes were determined and a 2.2-fold increase in K(m) was observed for Met(209)Leu. Comparison of Met(156)Leu and wild-type DAAO revealed a 95% increase in k(cat)/K(m). Met(156)Leu, Met(209)Leu, and Met(226)Leu were resistant to inactivation by 50 mM H(2)O(2). The other three mutant DAAOs were also slightly more resistant than the wild-type enzyme to chemical oxidation. These observations indicate that the oxidative stability in T. variabilis DAAO can be improved by substitution of methionine residues with leucine.

To investigate the functional role of an invariant histidine residue in Trigonopsis variabilis D-amino acid oxidase (DAAO), a set of mutant enzymes with replacement of the histidine residue at position 324 was constructed and their enzymatic properties were examined. Wild-type and mutant enzymes have been purified to homogeneity using the His-bound column and the molecular masses were determined to be 39.2 kDa. Western blot analysis revealed that the in vivo synthesized mutant enzymes are immuno-identical with that of the wild-type DAAO. The His324Asn and His324Gln mutants displayed comparable enzymatic activity to that of the wild-type enzyme, while the other mutant DAAOs showed markedly decreased or no detectable activity. The mutants, His324/Asn/Gln/Ala/Tyr/Glu, exhibited 38-181% increase in Km and a 2-10-fold reduction in kcat/Km. Based on the crystal structure of a homologous protein, pig kidney DAAO, it is suggested that His324 might play a structural role for proper catalytic function of T. variabilis DAAO.

Background: Traditional pleurodesis for malignant pleural effusion is performed by large-bore chest tube insertion with the instillation of sclerosing agents after the compressed lung re-expansion and pleural fluid drainage of 100-150 ml/day. This study was carried out to evaluate the possibility of rapid sclerotherapy for malignant pleural effusions by insertion of a small-bore Elecath tube (12-French) under ultrasound guidance and intrapleural injection of bleomycin 60 IU., Methods: Twenty-six patients, with 28 cytopathologically proven malignant pleural effusions (two patients had bilateral pleural effusions) and receiving the insertion of the Elecath tube for drainage, were included in our series. This rapid and short-term sclerosing method was performed and completed by intrapleural injection of bleomycin when the pleural effusion had been clearly drained by the small-bore Elecath tube and the compressed lung had fully re-expanded on follow-up chest radiographs., Results: Twenty patients with 22 pleural effusions underwent the intrapleural injection of bleomycin, with the results of pleurodesis being complete response 41% (9/22), partial response 36% (8/22) and failure 23% (5/22). Interestingly, among the 17 successful procedures of pleurodesis (complete response and partial response), 71% (12) procedures could be completed within 2 days (seven within one day and five within 2 days). The remaining unsuccessful procedures carried out on six patients without the injection of bleomycin were due to a non-re-expanded lung (n = 3) and inadequate drainage (n = 3); of these, four patients also received the large-bore chest tube insertion after the removal of the Elecath tube, but the compressed lung still could not re-expand. The complications of the bleomycin injection were fever [77% (17/22)], vomiting [14% (3/22)] and hiccup [5% (1/22)]., Conclusion: The method of rapid sclerotherapy for malignant pleural effusions by small-bore Elecath tube is promising, with a success rate achieving 77%, usually within 2 days.

We studied the mechanisms underlying alpha2-adrenergic receptor (AR)-mediated increase in intracellular free calcium ([Ca2+]i) in freshly dispersed myometrial cells from sows in the luteal phase of the estrous cycle. After the blockade of beta-ARs with propranolol, epinephrine increased [Ca2+]i dose-dependently in both the presence and absence of extracellular Ca2+. The rank order of alpha antagonists in inhibiting [Ca2+]i response to epinephrine was yohimbine > WB4101 >> prazosin in both the presence and absence of extracellular Ca2+, suggesting that epinephrine acts on alpha(2A)-ARs to increase Ca2+ influx as well as Ca2+ release from intracellular stores. Thapsigargin, the blocker of the Ca2+ pump in the sarcoplasmic reticulum, abolished the release but did not affect the influx. Pertussis toxin (PTX) inhibited the influx but failed to change the release. Nimodipine, an L-type Ca2+ channel blocker, nearly abolished the influx. The peak increase in [Ca2+]i caused by epinephrine was reached within 20 sec of administration. Intracellular cAMP concentrations were also decreased at 20 sec post-epinephrine. Epinephrine enhanced the L-type Ca2+ channel current, whereas forskolin suppressed it. Maximization of intracellular cAMP content by applying 8-bromo-cAMP (100 microM) blocked the effect of epinephrine on the current. U-73122, a phospholipase C inhibitor, reduced the Ca2+ release by epinephrine and oxytocin. Our results suggested that 1) activation of alpha2-ARs induces Ca2+ influx through opening L-type Ca2+ channels as well as inducing Ca2+ release from intracellular stores, and 2) a PTX-sensitive G protein couples negatively to adenylyl cyclase, leading to a decrease in cAMP formation which may be involved in the activation of Ca2+ channels. In addition, our results are consistent with the coupling of alpha2-ARs to a PTX-insensitive G protein (G(q)) to release Ca2+ from intracellular stores.

Bacillus sp. TS-23 amylase gene was amplified by polymerase chain reaction and cloned into the pET23(+) transcription vector. Lactose induction of Escherichia coli BL21(DE3) cells harbouring this recombinant plasmid resulted in the extracellular production of gene products. By the addition of 20 mmol l-1 lactose, the amylase activity of fermentation broth had a specific activity of 21 U mg-1 of protein.

An alpha-amylase gene from Bacillus sp. strain TS-23 was cloned and expressed by using its own promoter on the recombinant plasmid pTS917 in Escherichia coli. A cell fractionation experiment revealed that approximately 60% of the amylase activity was in the periplasmic space. Analysis and activity staining of the concentrated supernatant fraction by SDS-polyacrylamide gel electrophoresis showed an apparent protein band with a mol. wt of approximately 65,000. The amylase gene (amyA) consisted of an open reading frame of 1,845 bp encoding a protein of 613 amino acids with a calculated mol. wt of 69,543. The predicted amino acid sequence showed high homology with Bacillus species, E. coli and Salmonella typhimurium alpha-amylases. Deletion of 96 amino acids from the C-terminal portion of the amylase did not result in the loss of amylolytic activity. The truncated amylase, deletion of the first 50 amino acids from the N-terminus, was overexpressed in E. coli system and refolded to yield an activable enzyme.

The present study was undertaken to investigate whether lysine vasopressin (LVP) induces porcine myometrial contractions by activating vasopressin or oxytocin (OT) receptors. Both LVP (3 x 10(-9)-10(-6) M) and OT (3 x 10(-11)-10(-8) M) increased contractility dose-dependently in myometrium from both the luteal phase and prepartum period. Comparison of EC50s showed that OT was 75 and 57 times more potent than LVP in increasing myometrial contractility in pregnant and nonpregnant sows, respectively. L-366,948 (10(-8), 3 x 10(-8), 10(-7) M), a highly selective OT receptor antagonist, inhibited LVP- and OT-induced increases in myometrial contractility dose-dependently in both pregnant and nonpregnant tissues with similar antagonist affinity values (pA2). The V1 antagonist d(CH2)5[D-[Tyr(Me)2]AVP also antagonized both LVP- and OT-induced increases in myometrial contractility, but higher concentrations (10(-7) and 10(-6) M) were required to achieve the antagonism. The V2 antagonist Aaa-D-Tyr(Et)-Phe-Val-Asn-Abu-Pro-Arg-Arg-NH2 (10(-6) M) did not alter this effect of LVP and OT. LVP (10(-9)-10(-6) M) and OT (10(-10)-10(-7) M) also increased intracellular Ca2+ ([Ca2+]i) concentrations in porcine myometrial cells from sows during the prepartum period in a dose-dependent manner, with OT being 14 times more potent than LVP. L-366,948 (10(-9)-3 x 10(-8) M) antagonized the effect of OT (10(-7) M) and LVP (10(-6) M) in a similar dose-dependent manner.(ABSTRACT TRUNCATED AT 250 WORDS)

The aro gene of Corynebacterium glutamicum CCRC 18310 encoding 3-deoxy-D-arabinoheptulosonate-7-phosphate (DAHP) synthase was isolated by complementation of a DAHP synthase-deficient mutant of Escherichia coli AB3257. The specific activity of DAHP synthase was increased four-fold in a C. glutamicum strain harboring the cloned aro gene. The complete nucleotide sequence of the aro gene and its 5' and 3' flanking regions has been determined. The sequence contained an open reading frame of 368 codons, from which a protein with a molecular mass of 39,340 Da could be predicted. The deduced amino acid sequence shows high identity with the aro gene products of E. coli and Salmonella typhimurium.

The nucleotide sequence of the coding and regulatory regions of the alpha-amylase-encoding gene (AMY) of Schwanniomyces occidentalis has been determined. This sequence contained an open reading frame of 512 codons, from which a protein with Mr of 53,723 could be predicted. A putative signal sequence encoding for 25 amino acids was proposed for the 5' end of the open reading frame. Regulatory sequences, such as TATA box, CCAAT box and a signal sequence for polyadenylation and transcription termination could be found in the flanking regions of AMY gene. The deduced amino acid sequence also contained four common conserved regions characteristic of other alpha-amylase proteins.

Activation of the sympathetic nervous system inhibits insulin secretion. We tested the hypothesis that activation of alpha 2-adrenergic receptors on the beta-cell by epinephrine or clonidine attenuates insulin release by an effect on the voltage-dependent Ca2+ channel (VDCC) and examined the role of G-proteins in this signal transduction pathway. Using a cultured SV40-transformed hamster beta-cell line (HIT cells) as a model system, we determined the effect of alpha 2-adrenergic agonists on insulin secretion, 86Rb+ efflux (a marker for K+ channel flux), and the free cytosolic Ca2+ level [( Ca2+]i) monitored in fura-2-loaded cells. In a dose-dependent manner, epinephrine and clonidine (10(-8)-10(-5)M) attenuated the increase in [Ca2+]i and insulin secretion induced by either K+ depolarization or stimulation of the VDCC with the agonist Bay K 8644. Epinephrine failed to affect the rise in [Ca2+]i induced by carbamylcholine, an agent that mobilizes intracellular Ca2+. Epinephrine also did not changes 86Rb+ efflux from HIT cells. The inhibitory effects of epinephrine were prevented by the alpha 2-adrenergic antagonist idazoxan, but were unaffected by the alpha 1-adrenergic antagonist phenoxybenzamine. Pretreatment of HIT cells with pertussis toxin (0.1 micrograms/ml) overnight abolished the inhibitory effects of epinephrine and clonidine on both [Ca2+]i and insulin secretion. These data suggest that one mechanism by which alpha 2-adrenergic agonists inhibit insulin secretion is by inhibiting Ca2+ influx through VDCC, an action that is mediated through a pertussis toxin-sensitive G-protein.

The effects of xylazine on porcine myometrial contractility were studied in vitro using uterine strips to determine the alpha 2-adrenergic influences during the diestrous stage of the estrous cycle. Xylazine (10(-8)-10(-5) M) caused a dose-dependent increase in the amplitude of myometrial contractility. The alpha 2-adrenoceptor antagonists idazoxan and yohimbine (10(-8)-10(-6) M) blocked the effects of xylazine in a dose-dependent manner. Yohimbine was approximately 10 times more potent than idazoxan in this regard. In contrast, an alpha 1-adrenoceptor antagonist prazosin (10(-7) and 10(-6) M) did not block the xylazine-induced increase in myometrial contractility, but a higher dose of prazosin (10(-5) M) did reduce the effects of xylazine. When the porcine uterine strips were pretreated with Ca2(+)-free Tyrod's solution or verapamil, a Ca2+ channel blocker, the effects of xylazine on myometrial contractility were completely abolished, whereas those of carbachol were only moderately reduced. The results suggest that the xylazine-induced myometrial contractility is mediated by alpha 2-adrenoceptors and that this effect is mediated, at least in part, by Ca2+ channels, whereas the effect of carbachol is attributed to an increase in both Ca2+ entry and release of Ca2+ from intracellular pools.

The mechanism by which xylazine raises plasma glucose but lowers insulin concentrations was examined in Holstein cows. Intravenous injection of xylazine (15-150 micrograms/kg) induced a dose-dependent hyperglycemia and hypoinsulinemia for 3-4 h. An alpha 2-adrenergic blocking agent, yohimbine, and an alpha 1- and alpha 2-adrenergic blocking agent, phentolamine, at 500 micrograms/kg each reduced or abolished xylazine-induced hyperglycemia and hypoinsulinemia. The alpha 1-adrenergic blocking agents, prazosin and phenoxybenzamine, at 500 micrograms/kg each did not exert such antagonism. Prazosin at the dose studied even prolonged xylazine-induced hypoinsulinemia. The alpha-adrenergic blocking agents alone at 500 micrograms/kg each did not change either plasma glucose or insulin concentrations. The present study suggests that xylazine-induced hyperglycemia and hypoinsulinemia are mediated by alpha 2-adrenergic receptors, possibly in beta-cells of pancreatic islets which inhibit the release of insulin. The present study further suggests the use of xylazine as a pharmacological tool in the study of adrenergic influence on in vivo insulin release.