ABSTRACT
Several long-period radio transients have recently been discovered, with strongly polarized coherent radio pulses appearing on timescales between tens to thousands of seconds1,2. In some cases, the radio pulses have been interpreted as coming from rotating neutron stars with extremely strong magnetic fields, known as magnetars; the origin of other, occasionally periodic and less-well-sampled radio transients is still debated3. Coherent periodic radio emission is usually explained by rotating dipolar magnetic fields and pair-production mechanisms, but such models do not easily predict radio emission from such slowly rotating neutron stars and maintain it for extended times. On the other hand, highly magnetic isolated white dwarfs would be expected to have long spin periodicities, but periodic coherent radio emission has not yet been directly detected from these sources. Here we report observations of a long-period (21 min) radio transient, which we have labelled GPM J1839-10. The pulses vary in brightness by two orders of magnitude, last between 30 and 300 s and have quasiperiodic substructure. The observations prompted a search of radio archives and we found that the source has been repeating since at least 1988. The archival data enabled constraint of the period derivative to <3.6 × 10-13 s s-1, which is at the very limit of any classical theoretical model that predicts dipolar radio emission from an isolated neutron star.
ABSTRACT
Fast radio bursts (FRBs) are millisecond-duration flashes of radio waves that are visible at distances of billions of light years1. The nature of their progenitors and their emission mechanism remain open astrophysical questions2. Here we report the detection of the multicomponent FRB 20191221A and the identification of a periodic separation of 216.8(1) ms between its components, with a significance of 6.5σ. The long (roughly 3 s) duration and nine or more components forming the pulse profile make this source an outlier in the FRB population. Such short periodicity provides strong evidence for a neutron-star origin of the event. Moreover, our detection favours emission arising from the neutron-star magnetosphere3,4, as opposed to emission regions located further away from the star, as predicted by some models5.
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Background: Practice guidelines based on a systematic review of the literature regarding the nonsurgical management of hepatocellular carcinoma (hcc) in North America are lacking. Resection and transplantation are the foundations for cure of hcc; however, most patients are diagnosed at an advanced stage, precluding those curative treatments. A number of local or regional therapies are used and are followed by systemic therapy for advanced or progressive disease. Other treatments are available, but their efficacy, compared with those standards, is not well known. Methods: First, systematic review questions were developed. Literature searches of the medline, embase, and Cochrane library databases (January 2000 to July 2018 or January 2005 to July 2018 depending on the question) were conducted; in addition, abstracts from the 2018 annual meeting of the American Society of Clinical Oncology were reviewed. A practice guideline was drafted that was then scrutinized by internal and external reviewers. Results: Seventy-seven studies were included in the guideline: no guidelines, two systematic reviews, and seventy-five primary studies published in full (including one pooled analysis). Five recommendations were developed. Conclusions: There is no evidence for or against the use of local or regional interventions other than transarterial chemoembolization for the treatment of intermediate- or advanced-stage hcc. Furthermore, there is no evidence to support the addition of sorafenib to any local or regional therapy. Sorafenib or lenvatinib are recommended for first-line systemic treatment of intermediate-stage hcc. Regorafenib or cabozantinib provide survival benefits when given as second-line treatment. Antiviral treatment is recommended in individuals with advanced hcc who are positive for the hepatitis B surface antigen.
Subject(s)
Carcinoma, Hepatocellular/drug therapy , Liver Neoplasms/drug therapy , HumansABSTRACT
OBJECTIVE: We conducted a 12-week double-blind study of stabilization pharmacotherapy in patients with remitted psychotic depression (PD). METHODS: Seventy-one persons aged 18 years or older who had achieved remission of PD when randomized to either olanzapine plus sertraline or olanzapine plus placebo were continued on the double-blind treatment associated with remission. Symptoms of depression and psychosis, and weight, were measured once every 4 weeks. Cholesterol, triglycerides, and glucose were measured at stabilization phase baseline and Week 12/termination. RESULTS: The effect of treatment did not significantly change with time for depression, weight, or metabolic measures in the stabilization phase. Eight of the 71 participants (11.3%; 95% CI: 5.8, 20.7) experienced a relapse of major depression, psychosis, or both. Treatment groups did not differ in the frequency of relapse. In the entire study group, the adjusted estimate for change in weight was an increase of 1.66 kg (95% CI: 0.83, 2.48) and the adjusted estimate for change in total cholesterol was a decrease of 14.8 mg/dL (95% CI: 3.5, 26.1) during the 12-week stabilization phase; the remaining metabolic measures did not significantly change. CONCLUSION: Continuation of acute treatment was associated with stability of remission.
Subject(s)
Depressive Disorder, Major/drug therapy , Olanzapine/therapeutic use , Psychotic Disorders/drug therapy , Sertraline/therapeutic use , Adult , Aged , Antidepressive Agents/therapeutic use , Antipsychotic Agents/therapeutic use , Blood Glucose/analysis , Blood Glucose/drug effects , Body Weight/drug effects , Cholesterol/blood , Depressive Disorder, Major/diagnosis , Diagnostic and Statistical Manual of Mental Disorders , Double-Blind Method , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Olanzapine/administration & dosage , Placebos/administration & dosage , Remission Induction/methods , Sertraline/administration & dosage , Triglycerides/bloodABSTRACT
OBJECTIVE: The aim of the present work was to make recommendations about the use of systemically administered drugs in combination or in sequence with radiation (rt) or surgery, or both, for cure or organ preservation, or both, in patients with locally advanced nonmetastatic (stages iii-ivb) squamous cell carcinoma of the head and neck (lascchn). METHODS: The Meta-analysis of Chemotherapy in Head and Neck Cancer (mach-nc) reports have, de facto, guided practice since 2000, and so we searched the literature for systematic reviews published from January 2000 to February 2015 in reference to five research questions. A search was also conducted up to February 2015 for randomized trials (rcts) not included in the meta-analyses. Recommendations were constructed using the Cancer Care Ontario Program in Evidence-Based Care practice guidelines development cycle. RESULTS: In addition to updated mach-nc reports, five additional meta-analyses and thirty rcts were identified. Five recommendations for lascchn treatment were generated based on those data. Concurrent chemoradiation (ccrt) is recommended to maximize the chance of cure in patients less than 71 years of age when rt is used as definitive treatment. The same recommendation also applies to patients with resected lascchn considered to be at high risk for locoregional recurrence. For lascchn patients who are candidates for organ preservation strategies and would otherwise require total laryngectomy, either ccrt or induction chemotherapy, followed by rt or surgery based on tumour response is recommended. The addition of cetuximab to intensified rt (concomitant boost or hyperfractionated schedule) is an alternative to ccrt. Routine use of induction chemotherapy to improve overall survival is not recommended. CONCLUSIONS: We were able to use high-level evidence from patients receiving rt as definitive or postoperative treatment to generate recommendations for the use of systemic therapy in the treatment of lascchn. A limitation is a lack of stratification for human papillomavirus-related cancers of the oropharynx. One rct provided evidence for the use of cetuximab as an alternative to chemotherapy in the definitive rt setting. Concurrent chemoradiation provides one strategy for larynx preservation, but the best strategy is unclear. Use of induction chemotherapy does not improve overall survival, and its use should be limited to patients requiring immediate tumour downsizing before local therapy.
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The objective of this systematic review was to provide current evidence regarding the use of adjuvant systemic chemotherapy for stage II and III colon cancer following curative intent surgery. MEDLINE and EMBASE databases and proceedings of American Society for Clinical Oncology and European Society of Medical Oncology/European Cancer Congress were searched through to August 2015. Systematic reviews (with or without meta-analyses) and randomised controlled trials were included. Patients with completely resected stage III colon cancer have an overall survival benefit from adjuvant chemotherapy. Combination chemotherapy (5-fluorouracil/leucovorin/oxaliplatin or capecitabine/oxaliplatin) provides a larger benefit than monotherapy but with additional toxicity. For stage II colon cancer, a clear overall survival benefit has not been shown. However, based on the subgroup analysis available, patients with high-risk stage II disease may benefit from adjuvant chemotherapy. Patients younger than 70 years of age may derive greater disease-free survival and overall survival benefit from adjuvant chemotherapy (in combination with oxaliplatin) compared with those older than 70 years. Stage II patients with microsatellite instability may have an overall survival detriment if given adjuvant chemotherapy.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Chemotherapy, Adjuvant/methods , Colonic Neoplasms/drug therapy , Colonic Neoplasms/surgery , Aged , Colonic Neoplasms/pathology , Female , Humans , Male , Neoplasm Staging , OntarioABSTRACT
PURPOSE: There is a lack of a valid, definition for skin ulcers in SSc to be used in clinical trials. Our aim was to develop a consensus definition for SSc-skin ulcers based on the results of a systematic literature review (SLR) for skin ulcer definitions and expert opinion; and to evaluate its face validity, reliability and feasibility. METHODS: SLR for skin ulcer definitions was conducted using PubMed, Web of Science, and Cochrane library for articles published from inception to January 1st, 2016. SSc experts were to discuss the definitions' categories and vote for the relevant terms. Reliability of the definition were tested in a second expert meeting, seven SSc experts evaluated 7 SSc pts with skin lesions twice. Face validity and feasibility evaluated by sending out case report forms(CRFs) to 4 SSc experts, they were asked to use the definition in 5 pts each. RESULTS: A total of 3464 abstracts and titles were screened, and 446 articles were fully evaluated. Of these, 66 met eligibility criteria and skin ulcer definitions were extracted. SSc experts discussed, refined and voted on the consensus definition using nominal process. Kappa for inter-, intra-rater rater agreement was 0.51, 0.90 respectively. The mean time to decide if the lesion is an ulcer was 7.4 sec. All investigators endorsed the face validity of the new definition in the CRFs. CONCLUSION: Using a SLR and a nominal technique, we developed a preliminary consensus-based definition of SSc-skin ulcers. Face validity, feasibility and reliability were demonstrated for the developed definition.
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BACKGROUND: Updated practice guidelines on adjuvant chemotherapy for completely resected colon cancer are lacking. In 2008, Cancer Care Ontario's Program in Evidence-Based Care developed a guideline on adjuvant therapy for stages ii and iii colon cancer. With newer regimens being assessed in this patient population and older agents being either abandoned because of non-effectiveness or replaced by agents that are more efficacious, a full update of the original guideline was undertaken. METHODS: Literature searches (January 1987 to August 2015) of medline, embase, and the Cochrane Library were conducted; in addition, abstracts from the American Society of Clinical Oncology, the European Society for Medical Oncology, and the European Cancer Congress were reviewed (the latter for January 2007 to August 2015). A practice guideline was drafted that was then scrutinized by internal and external reviewers whose comments were incorporated into the final guideline. RESULTS: Twenty-six unique reports of eighteen randomized controlled trials and thirteen unique reports of twelve meta-analyses or pooled analyses were included in the evidence base. The 5 recommendations developed included 3 for stage ii colon cancer and 2 for stage iii colon cancer. CONCLUSIONS: Patients with completely resected stage iii colon cancer should be offered adjuvant 5-fluorouracil (5fu)-based chemotherapy with or without oxaliplatin (based on definitive data for improvements in survival and disease-free survival). Patients with resected stage ii colon cancer without "high-risk" features should not receive adjuvant chemotherapy. For patients with "high-risk" features, 5fu-based chemotherapy with or without oxaliplatin should be offered, although no clinical trials have been conducted to conclusively demonstrate the same benefits seen in stage iii colon cancer.
ABSTRACT
OBJECTIVE: Unipolar psychotic depression (PD) is a severe and debilitating syndrome, which requires intensive monitoring. The objective of this study was to provide an overview of the rating scales used to assess illness severity in PD. METHOD: Selective review of publications reporting results on non-self-rated, symptom-based rating scales utilized to measure symptom severity in PD. The clinical and psychometric validity of the identified rating scales was reviewed. RESULTS: A total of 14 rating scales meeting the predefined criteria were included in the review. These scales grouped into the following categories: (i) rating scales predominantly covering depressive symptoms, (ii) rating scales predominantly covering psychotic symptoms, (iii) rating scales covering delusions, and (iv) rating scales covering PD. For the vast majority of the scales, the clinical and psychometric validity had not been tested empirically. The only exception from this general tendency was the 11-item Psychotic Depression Assessment Scale (PDAS), which was developed specifically to assess the severity of PD. CONCLUSION: In PD, the PDAS represents the only empirically derived rating scale for the measurement of overall severity of illness. The PDAS should be considered in future studies of PD and in clinical practice.
Subject(s)
Bipolar and Related Disorders/diagnosis , Depressive Disorder/diagnosis , Psychiatric Status Rating Scales , Psychometrics/instrumentation , Psychotic Disorders/diagnosis , Severity of Illness Index , HumansABSTRACT
Despite rapid doubling time, simple architecture and ease of metabolic labelling, a lack of genetic tools in the Lemnaceae (duckweed) has impeded the full implementation of this organism as a model for biological research. Here, we present technologies to facilitate high-throughput genetic studies in duckweed. We developed a fast and efficient method for producing Lemna minor stable transgenic fronds via Agrobacterium-mediated transformation and regeneration from tissue culture. Additionally, we engineered an artificial microRNA (amiRNA) gene silencing system. We identified a Lemna gibba endogenous miR166 precursor and used it as a backbone to produce amiRNAs. As a proof of concept we induced the silencing of CH42, a magnesium chelatase subunit, using our amiRNA platform. Expression of CH42 in transgenic L. minor fronds was significantly reduced, which resulted in reduction of chlorophyll pigmentation. The techniques presented here will enable tackling future challenges in the biology and biotechnology of Lemnaceae.
Subject(s)
Araceae/genetics , Gene Silencing , MicroRNAs/metabolism , Transformation, Genetic , Base Sequence , DNA, Bacterial/genetics , Down-Regulation/genetics , Gene Expression Regulation, Plant , Green Fluorescent Proteins/metabolism , MicroRNAs/genetics , Molecular Sequence Data , Mutagenesis, Insertional/genetics , Phenotype , Plants, Genetically Modified , Polymerase Chain Reaction , RNA, Messenger/genetics , RNA, Messenger/metabolism , RegenerationABSTRACT
BACKGROUND: Preoperative chemoradiotherapy (CRT) improves outcomes in patients with locally advanced but resectable adenocarcinoma of the esophagus. ACOSOG Z4051 evaluated CRT with docetaxel, cisplatin, and panitumumab (DCP) in this patient group with a primary end point of a pathologic complete response (pCR) ≥35%. PATIENTS AND METHODS: From 15 January 2009 to 22 July 2011, 70 patients with locally advanced but resectable distal esophageal adenocarcinoma were enrolled. Patients received docetaxel (40 mg/m(2)), cisplatin (40 mg/m(2)), and panitumumab (6 mg/kg) on weeks 1, 3, 5, 7, and 9 with RT (5040 cGy, 180 cGy/day × 28 days) beginning week 5. Resection was planned after completing CRT. PCR was defined as no viable residual tumor cells. Secondary objectives included near-pCR (≤10% viable cancer cells), toxicity, and overall and disease-free survival. Adverse events were graded using the CTCAE Version 3.0. RESULTS: Five of 70 patients were ineligible. Of 65 eligible patients (59 M; median age 61), 11 did not undergo surgery, leaving 54 assessable. PCR rate was 33.3% and near-pCR was 20.4%. Secenty-three percent of patients completed DCP (n = 70) and 92% completed RT. 48.5% had toxicity ≥grade 4. Lymphopenia (43%) was most common. Operative mortality was 3.7%. Adult respiratory distress syndrome was encountered in two patients (3.7%). At median follow-up of 26.3 months, median overall survival was 19.4 months and 3-year overall survival was 38.6% (95% confidence interval 24.5% to 60.8%). CONCLUSIONS: Neoadjuvant CRT with DCP is active (pCR + near-pCR = 53.7%) but toxicity is significant. Further evaluation of this regimen in an unselected population is not recommended. CLINICALTRIALSGOV IDENTIFIER: NCT00757172.
Subject(s)
Adenocarcinoma/therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Esophageal Neoplasms/therapy , Esophagogastric Junction/pathology , Adenocarcinoma/mortality , Adult , Aged , Antibodies, Monoclonal/administration & dosage , Chemoradiotherapy, Adjuvant , Cisplatin/administration & dosage , Disease-Free Survival , Docetaxel , Esophageal Neoplasms/mortality , Esophagogastric Junction/surgery , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoadjuvant Therapy , Panitumumab , Taxoids/administration & dosage , Treatment OutcomeABSTRACT
OBJECTIVE: Psychotic depression (PD) is a highly debilitating condition, which needs intensive monitoring. However, there is no established rating scale for evaluating the severity of PD. The aim of this analysis was to assess the psychometric properties of established depression rating scales and a number of new composite rating scales, covering both depressive and psychotic symptoms, in relation to PD. METHOD: The psychometric properties of the rating scales were evaluated based on data from the Study of Pharmacotherapy of Psychotic Depression. RESULTS: A rating scale consisting of the 6-item Hamilton melancholia subscale (HAM-D6 ) plus five items from the Brief Psychiatric Rating Scale (BPRS), named the HAMD-BPRS11 , displayed clinical validity (Spearman's correlation coefficient between HAMD-BPRS11 and Clinical Global Impression - Severity (CGI-S) scores = 0.79-0.84), responsiveness (Spearman's correlation coefficient between change in HAMD-BPRS11 and Clinical Global Impression - Improvement (CGI-I) scores = -0.74--0.78) and unidimensionality (Loevinger's coefficient of homogeneity = 0.41) in the evaluation of PD. The HAM-D6 fulfilled the same criteria, whereas the full 17-item Hamilton Depression Scale failed to meet criteria for unidimensionality. CONCLUSION: Our results suggest that the HAMD-BPRS11 is a more valid measure than pure depression scales for evaluating the severity of PD.
Subject(s)
Affective Disorders, Psychotic/diagnosis , Psychiatric Status Rating Scales/standards , Adult , Affective Disorders, Psychotic/physiopathology , Brief Psychiatric Rating Scale , Depressive Disorder/diagnosis , Depressive Disorder/physiopathology , Female , Humans , Male , Middle Aged , Principal Component Analysis , Psychometrics/instrumentation , Randomized Controlled Trials as Topic , Reproducibility of Results , Severity of Illness IndexABSTRACT
microRNAs (miRNAs) function via targeting of messenger RNAs, suppressing protein levels, and playing important roles in biological processes of plants and animals. The pathway for miRNA biogenesis is well established, but less is known about miRNA turnover, largely because of difficulties in capturing miRNAs during the process of decay, in which they are both rare and ephemeral. The HEN1 protein methylates the 3' terminus of small RNAs (sRNAs), protecting them from poly-urydilation and degradation. Recent progress using deep sequencing to study sRNAs in hen1 reveals the potential for hen1 mutants to serve as a platform for studies of miRNA turnover, with the sequencing data providing unprecedented precision and detail in the characterization of 3' modifications.
Subject(s)
Arabidopsis Proteins/genetics , Arabidopsis/genetics , High-Throughput Nucleotide Sequencing , Mutation/genetics , RNA Processing, Post-Transcriptional/genetics , RNA, Plant/metabolism , Base Sequence , Molecular Sequence DataABSTRACT
Immune responses to human leucocyte antigen (HLA) and self-antigen collagen V (Col-V) have been proposed in the pathogenesis of chronic rejection (bronchiolitis obliterans syndrome, BOS) following human lung transplantation (LTx). In this study, we defined the role for the shift in immunodominant epitopes of Col-V in inducing T helper phenotype switch leading to immunity to Col-V and BOS. Sera and lavage from BOS(+) LTx recipients with antibodies to Col-V were analysed. Two years prior to BOS, patients developed antibodies to both Col-V,α1(V) and α2(V) chains. However, at clinical diagnosis of BOS, antibodies became restricted to α1(V). Further, lung biopsy from BOS(+) patients bound to antibodies to α1(V), indicating that these epitopes are exposed. Fourteen Col-V peptides [pep1-14, pep1-4 specific to α1(V), pep5-8 to α1,2(V) and pep9-14 to α2(V)] which bind to HLA-DR4 and -DR7, demonstrated that prior to BOS, pep 6, 7, 9, 11 and 14 were immunodominant and induced interleukin (IL)-10. However, at BOS, the response switched to pep1, 4 and 5 and induced interferon (IFN)-γ and IL-17 responses, but not IL-10. The T helper (Th) phenotype switch is accompanied by decreased frequency of regulatory T cells (T(regs) ) in the lavage. LTx recipients with antibodies to α1(V) also demonstrated increased matrix metalloproteinase (MMP) activation with decreased MMP inhibitor, tissue inhibitor of metalloproteinase (TIMP), suggesting that MMP activation may play a role in the exposure of new Col-V antigenic epitopes. We conclude that a shift in immunodominance of self-antigenic determinants of Col-V results in induction of IFN-γ and IL-17 with loss of tolerance leading to autoimmunity to Col-V, which leads to chronic lung allograft rejection.
Subject(s)
Autoantigens/immunology , Bronchiolitis Obliterans/immunology , Collagen Type I/immunology , Collagen Type V/immunology , Graft Rejection/immunology , Immunodominant Epitopes/immunology , Lung Transplantation/immunology , Self Tolerance/immunology , T-Lymphocytes, Helper-Inducer/immunology , Adult , Amino Acid Sequence , Bronchiolitis Obliterans/etiology , DNA Methylation , Enzyme Activation , Female , Follow-Up Studies , Forkhead Transcription Factors/genetics , Humans , Immunophenotyping , Immunosuppressive Agents/therapeutic use , Interferon-gamma/biosynthesis , Interferon-gamma/genetics , Interleukin-17/biosynthesis , Interleukin-17/genetics , Isoantigens/immunology , Lung/immunology , Lung/pathology , Male , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Middle Aged , Molecular Sequence Data , Peptide Fragments/immunology , Transplantation Tolerance/immunologyABSTRACT
BACKGROUND: Laboratory diagnosis of von Willebrand disease (VWD) requires accurate measurement of plasma von Willebrand factor (VWF) activity. OBJECTIVES: To evaluate laboratory characteristics, diagnostic accuracy and testing utilities of an automated latex particle-enhanced immunoturbidimetric VWF assay (VWF:Lx) based on a monoclonal antibody recognizing the VWF-platelet glycoprotein (GP) Ib binding domain. METHODS: Laboratory characteristics including lower detection limit, linearity, precision, sample stability, and method comparison between VWF:Lx and VWF ristocetin cofactor activity by platelet aggregometry (VWF:RCo) were examined. To assess VWF:Lx diagnostic accuracy, 492 patient plasma samples, including 40 previously characterized VWD patient samples, were tested for VWF antigen (VWF:Ag) and VWF:RCo by either aggregometry or flow cytometry, and VWF:Lx with supplemental VWF multimer analysis when indicated. Based on results of VWF:Ag, VWF:RCo and VWF multimer analysis, and available clinical information, samples were categorized as: normal; VWD types 1, 2A/B, 2M, or severe 1 vs. 2M; or acquired VWF abnormalities (AVWA) due to subtle loss of highest molecular weight multimers. RESULTS: VWF:Lx had excellent laboratory characteristics and linear correlation with VWF:RCo (R(2) = 0.93). VWF:Lx accurately classified virtually all normal and VWD patient samples. Compared with VWF:RCo, VWF:Lx had superior sensitivity and specificity for distinguishing severe type 1 vs. 2M VWD and identifying AVWA. A proposed screening panel comprising VWF:Ag and VWF:Lx had 100% and 83% sensitivity for detecting VWD and AVWA, respectively. CONCLUSIONS: VWF:Lx has excellent laboratory characteristics and diagnostic accuracy compared with VWF:RCo, and can be used as part of an initial VWD screening panel and as a supplementary test.
Subject(s)
Automation , Latex , Nephelometry and Turbidimetry/methods , von Willebrand Diseases/diagnosis , von Willebrand Factor/analysis , Flow Cytometry , Humans , von Willebrand Diseases/bloodABSTRACT
Sex differences and gonadal hormone influences are well known for diverse aspects of forebrain amine and indolamine neurotransmitter systems, the cognitive and affective functions they govern and their malfunction in mental illness. This study explored whether hormone regulation/dysregulation of these systems could be related to gonadal steroid effects on catechol-O-methyltransferase and monoamine oxidase which are principal enzymatic controllers of forebrain dopamine, serotonin and norepinephrine levels. Driven by male over female differences in cortical enzyme activities, by male-specific associations between monoamine oxidase and catechol-O-methyltransferase gene polymorphisms and cognitive and dysfunction in disease and by male-specific consequences of gene knockouts in mice, the question of hormone sensitivity was addressed here using a male rat model where prefrontal dopamine levels and related behaviors are also known to be affected. Specifically, quantitative O-methylation and oxidative deamination assays were used to compare the activities of catechol-O-methyltransferase's soluble and membrane-bound isoforms and of monoamine oxidase's A and B isoforms in the pregenual medial prefrontal cortex and dorsal striatum of male rats that were sham operated, gonadectomized or gonadectomized and supplemented with testosterone propionate or with estradiol for 28 days. These studies revealed significant effects of hormone replacement but not gonadectomy on the soluble but not the membrane-bound isorfom of catechol-O-methyltransferase in both striatum and cortex. A significant, cortex-specific testosterone-but not estradiol-attenuated effect (increase) of gonadectomy on monoamine oxidase's A but not B isoform was also observed. Although none of these actions suggest potential roles in the regulation/dysregulation of prefrontal dopamine, the suppressive effects of testosterone on cortical monoamine oxidase-A that were observed could have bearing on the increased incidence of cognitive deficits and symptoms of depression and anxiety that are repeatedly observed in males in conditions of hypogonadalism related to aging, other biological factors or in prostate cancer where androgen deprivation is used as a neoadjuvant treatment.
Subject(s)
Catechol O-Methyltransferase/metabolism , Estradiol/metabolism , Monoamine Oxidase/metabolism , Neostriatum/metabolism , Prefrontal Cortex/metabolism , Testosterone Propionate/metabolism , Aging , Animals , Cell Membrane/enzymology , Cell Membrane/metabolism , Hormone Replacement Therapy , Isoenzymes/metabolism , Male , Neostriatum/enzymology , Orchiectomy , Prefrontal Cortex/enzymology , Rats , Rats, Sprague-DawleyABSTRACT
BACKGROUND: Sex differences (or a 'sex gap') exist in the rates of cardiac revascularization. It was evaluated whether physician preference contributes to this difference. OBJECTIVES: To obtain information on how cardiac specialists manage male and female patients being evaluated for coronary artery disease. METHODS: A computer-based patient simulation program was developed. Six sex-matched clinical vignettes (three pairs) with uninterpreted coronary angiograms were shown to specialists, who were blinded to the purpose of the study. The sex-matched scenarios were balanced with respect to symptoms, comorbidities and coronary anatomy. Physicians were surveyed on management and rationale. RESULTS: Fifty physicians were surveyed, consisting mainly of cardiologists from tertiary cardiac centres in Ontario. Among the three sexmatched pairs, the frequencies at which percutaneous coronary intervention (including drug-eluting stents), bypass surgery and medical therapy were chosen did not differ across sexes. The means for men and women, respectively, were 47% and 50% for percutaneous coronary intervention, 32% and 26% for bypass surgery, and 21% and 24% for medical treatment. CONCLUSIONS: In the present pilot study, cardiac specialists chose similar rates of medical, interventional and surgical procedures independent of a patient's sex. Although large registry trials show that sex differences in management exist, the present data suggest that cardiac specialist preference is less likely to be a factor if coronary angiography was performed. Further research is required to explore the causes of sex discrepancies in cardiac care.
Subject(s)
Angioplasty, Balloon, Coronary/standards , Computer Simulation , Coronary Artery Bypass/standards , Coronary Artery Disease/mortality , Coronary Artery Disease/therapy , Aged , Angioplasty, Balloon, Coronary/trends , Attitude of Health Personnel , Cardiology/standards , Cardiology/trends , Confidence Intervals , Coronary Artery Bypass/trends , Coronary Artery Disease/diagnostic imaging , Female , Health Care Surveys , Hospitals, University , Humans , Male , Middle Aged , Ontario , Pilot Projects , Practice Patterns, Physicians'/standards , Practice Patterns, Physicians'/trends , Probability , Quality of Health Care , Radiography , Risk Assessment , Severity of Illness Index , Sex Factors , Surveys and Questionnaires , Survival Analysis , Treatment OutcomeABSTRACT
The prefrontal cortices mediate cognitive functions that critically depend on local dopamine levels. In male rats, many prefrontal tasks where performance is disrupted by changes in dopamine signaling are also impaired by gonadectomy, a manipulation that increases cortical dopamine concentration, prefrontal dopamine axon density and possibly extracellular prefrontal dopamine levels as well. Because these actions could be responsible for the impairing effects of gonadectomy on prefrontal function, the question of how they might arise comes to the fore. Accordingly, the present studies asked whether dopamine levels might be increased via a hormone sensitivity of transporter-mediated dopamine uptake. Specifically, (3)H WIN 35,428 and (3)H nisoxetine, ligands selective for the dopamine (DAT)- and norepinephrine transporter (NET) respectively, were used in in vitro binding assays to ask whether gonadectomy altered transporter affinity (Kd) and/or binding site number (Bmax) in prefrontal cortex, sensorimotor cortex and/or caudate. Assays performed on tissues dissected from sham-operated, gonadectomized and gonadectomized rats supplemented with testosterone propionate or estradiol for 4 or 28 days revealed no significant group differences or obvious trends in Kd or Bmax for DAT binding or in measures of Bmax for NET binding. However, affinity constants for (3)H nisoxetine were found to be significantly higher in sensorimotor and/or prefrontal cortex of rats gonadectomized and gonadectomized and supplemented with estradiol for 4 or 28 days but similar to control in gonadectomized rats given testosterone. Because the NET contributes substantially to extracellular prefrontal dopamine clearance, these androgen-mediated effects could influence prefrontal dopamine levels and might thus be relevant for observed effects of gonadectomy on dopamine-dependent prefrontal behaviors. A hormone sensitivity of the NET could also have bearing on the prefrontal dopamine dysfunction seen in disorders like schizophrenia that disproportionately affect males, whose severity correlates with abnormal testosterone levels, and for which the NET is among suspected sites of pathology.
Subject(s)
Cerebral Cortex/drug effects , Cocaine/analogs & derivatives , Dopamine Plasma Membrane Transport Proteins/metabolism , Dopamine Uptake Inhibitors/metabolism , Fluoxetine/analogs & derivatives , Gonadal Hormones/pharmacology , Norepinephrine Plasma Membrane Transport Proteins/metabolism , Animals , Cerebral Cortex/metabolism , Cocaine/metabolism , Dopamine/metabolism , Dose-Response Relationship, Drug , Estradiol/pharmacology , Fluoxetine/metabolism , Male , Norepinephrine Plasma Membrane Transport Proteins/antagonists & inhibitors , Orchiectomy , Protein Binding/drug effects , Rats , Rats, Sprague-Dawley , Testosterone Propionate/pharmacology , Time Factors , Tritium/metabolismABSTRACT
SUMMARY: Accurate staging of esophageal cancer is critical to achieving optimal treatment outcomes. End-oscopic ultrasound with fine needle aspiration (EUS-FNA) has emerged as a valuable tool for locoregional staging. However, it is unclear how different physician specialties perceive the benefit of EUS-FNA for esophageal cancer staging, and thus utilize this modality in clinical practice. A survey regarding utilization of EUS-FNA in esophageal cancer was distributed to 211 thoracic surgeons and 251 EUS-capable gastroenterologists. Seventy-six thoracic surgeons (36%) and 78 gastroenterologists (31%) responded to the survey. Most surgeons (75%) use EUS to stage potentially resectable esophageal cancer 75% of the time. Surgeons using EUS less often are less likely to have access to high-quality EUS services than their peers. Fewer surgeons believe EUS is the most accurate test for T and N-staging (84% and 71%, respectively) as compared with gastroenterologists (97% and 96%, P < 0.01 for both). Most endosonographers (68%) decide whether to dilate a malignant esophageal stricture to complete the staging exam on a case-by-case basis. Surgeons disagree as to whether involvement of celiac lymph nodes should preclude esophagectomy in distal esophageal cancer. While most thoracic surgeons have embraced EUS-FNA as the most accurate locoregional staging modality in esophageal cancer, this attitude is not fully reflected in utilization patterns due to a lack of quality EUS services in some centers. Controversial areas that warrant further study include dilation of malignant strictures to facilitate EUS staging, and the implication of involved celiac lymph nodes on management.