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1.
Antibiotics (Basel) ; 12(4)2023 Mar 30.
Article in English | MEDLINE | ID: mdl-37107041

ABSTRACT

The growing emergence of multidrug resistance in bacterial pathogens is an immediate threat to human health worldwide. Unfortunately, there has not been a matching increase in the discovery of new antibiotics to combat this alarming trend. Novel contemporary approaches aimed at antibiotic discovery against Gram-negative bacterial pathogens have expanded focus to also include essential surface-exposed receptors and protein complexes, which have classically been targeted for vaccine development. One surface-exposed protein complex that has gained recent attention is the ß-barrel assembly machinery (BAM), which is conserved and essential across all Gram-negative bacteria. BAM is responsible for the biogenesis of ß-barrel outer membrane proteins (ß-OMPs) into the outer membrane. These ß-OMPs serve essential roles for the cell including nutrient uptake, signaling, and adhesion, but can also serve as virulence factors mediating pathogenesis. The mechanism for how BAM mediates ß-OMP biogenesis is known to be dynamic and complex, offering multiple modes for inhibition by small molecules and targeting by larger biologics. In this review, we introduce BAM and establish why it is a promising and exciting new therapeutic target and present recent studies reporting novel compounds and vaccines targeting BAM across various bacteria. These reports have fueled ongoing and future research on BAM and have boosted interest in BAM for its therapeutic promise in combatting multidrug resistance in Gram-negative bacterial pathogens.

2.
Rev Fish Biol Fish ; 32(1): 253-270, 2022.
Article in English | MEDLINE | ID: mdl-33456210

ABSTRACT

Ocean governance is complex and influenced by multiple drivers and actors with different worldviews and goals. While governance encompasses many elements, in this paper we focus on the processes that operate within and between states, civil society and local communities, and the market, including industry. Specifically, in this paper, we address the question of how to move towards more sustainable ocean governance aligning with the sustainable development goals (SDGs) and the UN Ocean Decade. We address three major risks to oceans that arise from governance-related issues: (1) the impacts of the overexploitation of marine resources; (2) inequitable distribution of access to and benefits from marine ecosystem services, and (3) inadequate or inappropriate adaptation to changing ocean conditions. The SDGs have been used as an underlying framework to develop these risks. We identify five drivers that may determine how ocean governance evolves, namely formal rules and institutions, evidence and knowledge-based decision-making, legitimacy of decision-making institutions, stakeholder engagement and participation, and empowering communities. These drivers were used to define two alternative futures by 2030: (a) 'Business as Usual'-a continuation of current trajectories and (b) 'More Sustainable Future'-optimistic, transformational, but technically achievable. We then identify what actions, as structured processes, can reduce the three major governance-related risks and lead to the More Sustainable Future. These actions relate to the process of co-creation and implementation of improved, comprehensive, and integrated management plans, enhancement of decision-making processes, and better anticipation and consideration of ambiguity and uncertainty. Supplementary information: The online version of this article (10.1007/s11160-020-09631-x) contains supplementary material, which is available to authorized users.

3.
Prog Biophys Mol Biol ; 166: 61-85, 2021 11.
Article in English | MEDLINE | ID: mdl-34197836

ABSTRACT

The funny current, If, was first recorded in the heart 40 or more years ago by Dario DiFrancesco and others. Since then, we have learnt that If plays an important role in pacemaking in the sinus node, the innate pacemaker of the heart, and more recently evidence has accumulated to show that If may play an important role in action potential conduction through the atrioventricular (AV) node. Evidence has also accumulated to show that regulation of the transcription and translation of the underlying Hcn genes plays an important role in the regulation of sinus node pacemaking and AV node conduction under normal physiological conditions - in athletes, during the circadian rhythm, in pregnancy, and during postnatal development - as well as pathological states - ageing, heart failure, pulmonary hypertension, diabetes and atrial fibrillation. There may be yet more pathological conditions involving changes in the expression of the Hcn genes. Here, we review the role of If and the underlying HCN channels in physiological and pathological changes of the sinus and AV nodes and we begin to explore the signalling pathways (microRNAs, transcription factors, GIRK4, the autonomic nervous system and inflammation) involved in this regulation. This review is dedicated to Dario DiFrancesco on his retirement.


Subject(s)
Atrial Fibrillation , Atrioventricular Node , Action Potentials , Heart Rate , Humans , Sinoatrial Node
4.
Circ Heart Fail ; 14(7): e007505, 2021 07.
Article in English | MEDLINE | ID: mdl-34190577

ABSTRACT

BACKGROUND: Purkinje fibers (PFs) control timing of ventricular conduction and play a key role in arrhythmogenesis in heart failure (HF) patients. We investigated the effects of HF on PFs. METHODS: Echocardiography, electrocardiography, micro-computed tomography, quantitative polymerase chain reaction, immunohistochemistry, volume electron microscopy, and sharp microelectrode electrophysiology were used. RESULTS: Congestive HF was induced in rabbits by left ventricular volume- and pressure-overload producing left ventricular hypertrophy, diminished fractional shortening and ejection fraction, and increased left ventricular dimensions. HF baseline QRS and corrected QT interval were prolonged by 17% and 21% (mean±SEMs: 303±6 ms HF, 249±11 ms control; n=8/7; P=0.0002), suggesting PF dysfunction and impaired ventricular repolarization. Micro-computed tomography imaging showed increased free-running left PF network volume and length in HF. mRNA levels for 40 ion channels, Ca2+-handling proteins, connexins, and proinflammatory and fibrosis markers were assessed: 50% and 35% were dysregulated in left and right PFs respectively, whereas only 12.5% and 7.5% changed in left and right ventricular muscle. Funny channels, Ca2+-channels, and K+-channels were significantly reduced in left PFs. Microelectrode recordings from left PFs revealed more negative resting membrane potential, reduced action potential upstroke velocity, prolonged duration (action potential duration at 90% repolarization: 378±24 ms HF, 249±5 ms control; n=23/38; P<0.0001), and arrhythmic events in HF. Similar electrical remodeling was seen at the left PF-ventricular junction. In the failing left ventricle, upstroke velocity and amplitude were increased, but action potential duration at 90% repolarization was unaffected. CONCLUSIONS: Severe volume- followed by pressure-overload causes rapidly progressing HF with extensive remodeling of PFs. The PF network is central to both arrhythmogenesis and contractile dysfunction and the pathological remodeling may increase the risk of fatal arrhythmias in HF patients.


Subject(s)
Action Potentials/physiology , Heart Failure/physiopathology , Heart Ventricles/physiopathology , Ventricular Remodeling/physiology , Animals , Cardiac Pacing, Artificial/adverse effects , Electrocardiography/methods , Heart Rate/physiology , Male , Models, Animal , Rabbits , X-Ray Microtomography/adverse effects
5.
Front Psychiatry ; 12: 660575, 2021.
Article in English | MEDLINE | ID: mdl-33841219

ABSTRACT

Novel psychoactive substances (NPS) are popular "club/party" drugs that first attracted attention in the UK in 2009 and remained legal until the 2016 Psychoactive Substances Act criminalized their distribution. Unlike "traditional" illicit drugs, very little is known about the influence of their analogs on neuropsychological functioning. We characterized the cognitive and emotional profile of NPS/polydrug users using the Cambridge Neuropsychological Test Automated Battery (CANTAB) and EMOTICOM test battery in adult male (aged 20-49 years) recreational users without psychiatric comorbidities (n = 27; "psychonauts"), service users attending a UK specialist "Club Drug" Clinic for problematic use (n = 20) and healthy control volunteers without significant drug-taking histories (n = 35). Tasks were selected to distinguish "hot" cognitive processes that are highly influenced by emotion from "cold" cognitive processes that are largely independent of emotional influence. Both user groups reported significantly higher sensation-seeking traits compared with non-users. Recreational NPS users demonstrated more risk-taking behavior compared with controls and treatment-seeking NPS users showed poorer learning, episodic memory and response inhibition compared with the other two groups. These effects persisted, when controlling for age, intelligence, alcohol and cannabis use severity, nicotine dependence, trait anxiety, depression, childhood adversity, impulsivity, and sensation seeking. Overall, recreational NPS users showed elevated "hot" (emotion-laden) cognition in the absence of "cold" (non-emotional) cognitive deficits, whereas "cold" cognitive dysfunction was pronounced in individuals seeking treatment for problematic NPS use. High trait impulsivity and poor self-control may confer additional risk to NPS/polydrug use severity and separate those seeking treatment from those using NPS recreationally.

6.
BMJ Open ; 11(2): e042729, 2021 02 22.
Article in English | MEDLINE | ID: mdl-33619189

ABSTRACT

INTRODUCTION: Chronic spinal pain (CSP) is the most common musculoskeletal disorder and is a leading cause of disability as per the Global Burden of Diseases. Previous reviews of microscopic changes in the spinal extensor muscles of people with CSP have focused on the lumbar region only and the results have been inconclusive. Therefore, in this protocol, we aim to assess microscopic changes in the extensor muscles of all spinal regions, investigating regionally specific changes in muscle fibre types of the spinal extensor muscles in patients with non-specific CSP. METHODS/ANALYSIS: This protocol was designed using Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines. Searches will use the following databases: MEDLINE, Embase, PubMed, CINAHL Plus and Web of Science along with relevant grey literature searches. Two reviewers will conduct the searches, perform data extraction, apply inclusion criteria and conduct risk of bias assessment using Newcastle-Ottawa Scale. Data will be synthesised and analysed independently. If there is sufficient homogeneity, then meta-analysis will be conducted by the reviewers jointly. If not, meta-synthesis or narrative reporting will be performed. The quality of the evidence will be assessed using Grading of Recommendations, Assessment, Development and Evaluation (GRADE) guidelines. ETHICS AND DISSEMINATION: The results of this study will be submitted for publication to a peer-reviewed journal and will be presented at conferences. Ethical approval for this systematic review was not required due to no patient data being collated. PROSPERO REGISTRATION NUMBER: CRD42020198087.


Subject(s)
Chronic Pain , Humans , Meta-Analysis as Topic , Muscle, Skeletal , Research Design
7.
Colorectal Dis ; 23(5): 1184-1192, 2021 May.
Article in English | MEDLINE | ID: mdl-33448576

ABSTRACT

AIM: Crohn's disease is a chronic inflammatory bowel disease characterized by alternating periods of exacerbation and remission. Surgical resection is not curative and postoperative recurrence (POR) remains a challenge in these patients. The aim of this study was to identify clinical variables that influence the risk of symptomatic anastomotic POR in patients with ileo-colonic Crohn's disease. METHOD: A retrospective study of Crohn's disease patients who had undergone ileo-colic resection between January 2014 and December 2018 was performed. For each patient, data including demographic information, Crohn's disease clinical setting, preoperative radiological data, operative and histological data, pre- and postoperative medication history and postoperative clinical course, including recurrence of disease, were extracted. Symptomatic anastomotic POR was defined as symptoms of Crohn's disease in the presence of confirmed anastomotic POR (endoscopic and/or radiological POR). RESULTS: For the study period, 104 patients were eligible and included for analysis. The cumulative probability of symptomatic anastomotic POR was 14%, 30%, 42%, 50% and 50% at 1, 2, 3, 4 and 5 years, respectively. Two clinical variables on multivariate analysis were associated with increased risk of symptomatic anastomotic POR, namely age <17 years at diagnosis [hazard ratio (HR) 2.17, p = 0.019] and gastrointestinal involvement (extent) >30 cm (HR 1.85, p = 0.048). CONCLUSION: This study describes the natural history of POR after ileo-colic resection for Crohn's disease, as defined by endoscopic, radiological and clinical outcomes. Age <17 years at diagnosis and gastrointestinal involvement (extent) >30 cm were independent risk factors for symptomatic anastomotic POR.


Subject(s)
Colic , Crohn Disease , Adolescent , Anastomosis, Surgical/adverse effects , Crohn Disease/surgery , Humans , Ileum/surgery , Recurrence , Retrospective Studies , Risk Factors
8.
J Cardiovasc Dev Dis ; 7(4)2020 Oct 29.
Article in English | MEDLINE | ID: mdl-33137874

ABSTRACT

In recent decades, investigators have strived to describe and quantify the orientation of the cardiac myocytes in an attempt to classify their arrangement in healthy and diseased hearts. There are, however, striking differences between the investigations from both a technical and methodological standpoint, thus limiting their comparability and impeding the drawing of appropriate physiological conclusions from the structural assessments. This review aims to elucidate these differences, and to propose guidance to establish methodological consensus in the field. The review outlines the theory behind myocyte orientation analysis, and importantly has identified pronounced differences in the definitions of otherwise widely accepted concepts of myocytic orientation. Based on the findings, recommendations are made for the future design of studies in the field of myocardial morphology. It is emphasised that projection of myocyte orientations, before quantification of their angulation, introduces considerable bias, and that angles should be assessed relative to the epicardial curvature. The transmural orientation of the cardiomyocytes should also not be neglected, as it is an important determinant of cardiac function. Finally, there is considerable disagreement in the literature as to how the orientation of myocardial aggregates should be assessed, but to do so in a mathematically meaningful way, the normal vector of the aggregate plane should be utilised.

9.
Sci Rep ; 10(1): 8158, 2020 05 18.
Article in English | MEDLINE | ID: mdl-32424129

ABSTRACT

In heart failure, myocardial overload causes vast metabolic changes that impair cardiac energy production and contribute to deterioration of contractile function. However, metabolic therapy is not used in heart failure care. We aimed to investigate the interplay between cardiac function and myocardial carbohydrate metabolism in a large animal heart failure model. Using magnetic resonance spectroscopy with hyperpolarized pyruvate and magnetic resonance imaging at rest and during pharmacological stress, we investigated the in-vivo cardiac pyruvate metabolism and contractility in a porcine model of chronic pulmonary insufficiency causing right ventricular volume overload. To assess if increasing the carbohydrate metabolic reserve improves the contractile reserve, a group of animals were fed dichloroacetate, an activator of pyruvate oxidation. Volume overload caused heart failure with decreased pyruvate dehydrogenase flux and poor ejection fraction reserve. The animals treated with dichloroacetate had a larger contractile response to dobutamine stress than non-treated animals. Further, dichloroacetate prevented myocardial hypertrophy. The in-vivo metabolic data were validated by mitochondrial respirometry, enzyme activity assays and gene expression analyses. Our results show that pyruvate dehydrogenase kinase inhibition improves the contractile reserve and decreases hypertrophy by augmenting carbohydrate metabolism in porcine heart failure. The approach is promising for metabolic heart failure therapy.


Subject(s)
Heart Failure/metabolism , Heart Failure/prevention & control , Hypertrophy/metabolism , Hypertrophy/prevention & control , Animals , Carbohydrate Metabolism , Carbohydrates/chemistry , Female , Heart/diagnostic imaging , Heart/physiopathology , Heart Failure/diagnostic imaging , Heart Failure/physiopathology , Heart Ventricles/diagnostic imaging , Heart Ventricles/metabolism , Heart Ventricles/physiopathology , Humans , Hypertrophy/drug therapy , Hypertrophy/physiopathology , Magnetic Resonance Spectroscopy , Myocardial Contraction , Myocardium/metabolism , Oxidation-Reduction , Pyruvate Dehydrogenase Complex/genetics , Pyruvate Dehydrogenase Complex/metabolism , Pyruvic Acid/metabolism , Swine
10.
Clin Genitourin Cancer ; 18(4): 274-283.e5, 2020 08.
Article in English | MEDLINE | ID: mdl-32335059

ABSTRACT

PURPOSE: To compare metastasis-free survival, overall survival, and patient-reported quality of life (QOL) of men with National Comprehensive Cancer Network high or very high risk prostate cancer after definitive surgery and/or multimodal radiotherapy (RT). PATIENTS AND METHODS: We studied a retrospective cohort study of 586 patients treated between the years 2000 and 2017 receiving radical prostatectomy with or without postoperative RT, external-beam RT (EBRT) with androgen deprivation therapy (ADT), or EBRT plus brachytherapy (Brachy) boost + ADT. Patient-reported QOL for urinary, bowel, sexual, and overall physical and mental functioning was assessed using the American Urological Association symptom scale, the Sexual Health Inventory in Men, the Rectal-Function Assessment Scale, the Expanded Prostate Cancer Index Composite, and the Veterans RAND 12-Item Health Survey. RESULTS: Median follow-up for survival was 5 years. No significant differences between the treatments were observed for overall survival or metastasis-free survival at the P < .05 threshold. The propensity-adjusted 5-year metastasis-free survival estimates for EBRT + ADT, EBRT + Brachy + ADT, and surgery were 74.6%, 94.8%, and 83.1%, respectively. The EBRT + Brachy + ADT and surgery cohorts had significantly worse mean American Urological Association symptom scores at 6 months than the EBRT + ADT cohort, which resolved by 1 year. Surgical patients had better rectal function scores than EBRT + ADT patients at years 1 to 3, but similar function thereafter. Adjuvant or salvage RT resulted in significant declines in various Expanded Prostate Cancer Index Composite urinary, sexual, and bowel domains, and Veterans RAND 12-Item Health Survey physical but not mental domains. CONCLUSION: Men with very and/or high-risk localized prostate cancer are likely to require multimodal therapy. The overall differences in survival and long-term QOL are similar for men choosing surgical versus RT pathways.


Subject(s)
Androgen Antagonists/therapeutic use , Brachytherapy/mortality , Prostatectomy/mortality , Prostatic Neoplasms/mortality , Prostatic Neoplasms/secondary , Quality of Life , Aged , Combined Modality Therapy , Follow-Up Studies , Humans , Male , Middle Aged , Patient Reported Outcome Measures , Prognosis , Prospective Studies , Prostatic Neoplasms/therapy , Retrospective Studies , Survival Rate , Watchful Waiting
11.
Biochim Biophys Acta Biomembr ; 1862(1): 183062, 2020 01 01.
Article in English | MEDLINE | ID: mdl-31520605

ABSTRACT

The ß-barrel assembly machinery (BAM) is responsible for the biogenesis of outer membrane proteins (OMPs) into the outer membranes of Gram-negative bacteria. These OMPs have a membrane-embedded domain consisting of a ß-barrel fold which can vary from 8 to 36 ß-strands, with each serving a diverse role in the cell such as nutrient uptake and virulence. BAM was first identified nearly two decades ago, but only recently has the molecular structure of the full complex been reported. Together with many years of functional characterization, we have a significantly clearer depiction of BAM's structure, the intra-complex interactions, conformational changes that BAM may undergo during OMP biogenesis, and the role chaperones may play. But still, despite advances over the past two decades, the mechanism for BAM-mediated OMP biogenesis remains elusive. Over the years, several theories have been proposed that have varying degrees of support from the literature, but none has of yet been conclusive enough to be widely accepted as the sole mechanism. We will present a brief history of BAM, the recent work on the structures of BAM, and a critical analysis of the current theories for how it may function.


Subject(s)
Bacterial Outer Membrane Proteins/chemistry , Protein Conformation, beta-Strand , Bacterial Outer Membrane Proteins/biosynthesis , Gram-Negative Bacteria/chemistry , Gram-Negative Bacteria/ultrastructure , Protein Structure, Secondary
12.
J Urban Health ; 97(1): 137-147, 2020 02.
Article in English | MEDLINE | ID: mdl-31172395

ABSTRACT

Sexual violence victimization is unacceptably common in the US, with nearly half of women and one in five men reporting lifetime sexual coercion and/or unwanted sexual contact; much violence occurs in campus settings. The majority of sexual violence prevention programs designed to date were not developed around the needs of urban commuter campus students. The present study explored qualitatively how these students conceptualize sexual violence and prevention. Face-to-face in-depth interviews were conducted with students on how they recognized sexual violence and understood prevention. Interviews were audiotaped, transcribed, and analyzed. Commuter students used "gut feelings" to identify sexual violence, reporting minimal direct consent communication. Intersecting social identities and multiple, concurrent roles limit the potential impact of existing prevention programs. Further research to design and evaluate tailored sexual violence prevention programming for urban commuter campus students is needed.


Subject(s)
Sex Offenses/psychology , Universities , Adolescent , Cities/epidemiology , Crime Victims/psychology , Female , Humans , Interviews as Topic , Male , Qualitative Research , Social Identification , Students , Young Adult
13.
Heart Rhythm ; 17(1): 123-130, 2020 01.
Article in English | MEDLINE | ID: mdl-31377422

ABSTRACT

BACKGROUND: The right ventricular outflow tract is the most common source of ventricular arrhythmias in nonstructural heart disease. Most of these arrhythmias are of endocardial origin, but their morphologic substrate is mostly unknown. OBJECTIVE: The purpose of this study was to identify potential morphologic substrates for such arrhythmias originating within the right ventricular outflow tract. METHODS: Three adult human hearts that had been fixed in 4% formaldehyde were examined. In 2 of the hearts, which were obtained subsequent to necropsies, the base of the anterior papillary muscle of the tricuspid valve was removed at the site of its fusion with the moderator band. The block of removed myocardium was submitted to routine histologic processing and sectioned at 5-µm thickness. The free-standing subpulmonary infundibulum also was removed as a series of macroscopic preparations, which were sectioned in their short axis at 5-µm thickness. The third heart was assessed using microcomputed tomography after it had been stained with 7.5% I2KI contrast agent for 14 days, with the contrast agent refreshed on the seventh day. RESULTS: Specialized conducting cardiomyocytes from the base of the anterior papillary muscle to the supraventricular crest and subpulmonary infundibulum were identified and tracked using histology in 2 hearts and microcomputed tomography in the other. Transitional cells were also found at these sites. CONCLUSION: The existence of such specialized cardiomyocytes within the infundibulum is of clinical significance because they could be the morphologic substrate for arrhythmias known to originate from these sites.


Subject(s)
Endocardium/pathology , Heart Conduction System/pathology , Myocytes, Cardiac/pathology , Tachycardia, Ventricular/pathology , Adult , Female , Humans , Male , X-Ray Microtomography
14.
NMR Biomed ; 33(3): e4205, 2020 03.
Article in English | MEDLINE | ID: mdl-31829484

ABSTRACT

Diffusion tensor imaging has been used for assessing the orientation of cardiac myocytes for decades. Striking methodological differences exist between studies when quantifying these orientations. This limits the comparability between studies, and impedes collaboration and the drawing of appropriate physiological conclusions. We have sought to elucidate these differences, permitting us to propose a standardised "tool set" that might better establish consensus in future studies. We fixed hearts from seven 25 kg pigs in formalin, and scanned them using diffusion tensor imaging. Using various angle definitions as found in literature, we assessed the orientations of cardiomyocytes, comparing them in terms of helical and intrusion angles, along with the orientation of their aggregations. The difference between assessment of the helical angle with and without relation to the epicardial curvature was 25.2° (SD: 7.9) at the base, 5.8° (1.9) at the equatorial level, and 28.0° (7.0) at the apex, ANOVA P = 0.001. In comparable fashion, the intrusion angle differed by 25.9° (12.9), 7.6° (0.98) and 17.5° (4.7), P = 0.01, and the angle of the aggregates (E3-angle) differed by 25.0° (13.5) at the base, 9.4° (1.7) at the equator, and 23.1° (6.2) apically, P = 0.003. When assessing 14 definitions used in literature to calculate the orientation of aggregates, only 4 rendered identical results. The findings show that any attempt to use projection of eigenvectors introduces considerable bias. The epicardial curvature of the ventricular cone needs to be taken into account when seeking to provide accurate quantification of the orientation of the aggregated cardiomyocytes, especially in the apical and basal regions. This means that projection of eigenvectors should be avoided prior to quantifying myocyte orientation, especially when assessing radial orientation. Based on our results, we suggest appropriate methods for valid assessment of myocyte orientation using diffusion tensor imaging.


Subject(s)
Diffusion Tensor Imaging , Myocytes, Cardiac/cytology , Animals , Female , Pericardium/anatomy & histology , Swine
15.
J Cardiovasc Magn Reson ; 21(1): 35, 2019 07 01.
Article in English | MEDLINE | ID: mdl-31256759

ABSTRACT

BACKGROUND: The three-dimensional rearrangement of the right ventricular (RV) myocardium during cardiac deformation is unknown. Previous in-vivo studies have shown that myocardial left ventricular (LV) deformation is driven by rearrangement of aggregations of cardiomyocytes that can be characterised by changes in the so-called E3-angle. Ex-vivo imaging offers superior spatial resolution compared with in-vivo measurements, and can thus provide novel insight into the deformation of the myocardial microstructure in both ventricles. This study sought to describe the dynamic changes of the orientations of the cardiomyocytes in both ventricles brought upon by cardiac contraction, with particular interest in the thin-walled RV, which has not previously been described in terms of its micro-architecture. METHODS: The hearts of 14 healthy 20 kg swine were excised and preserved in either a relaxed state or a contracted state. Myocardial architecture was assessed and compared between the two contractional states by quantification of the helical, transmural and E3-angles of the cardiomyocytes using high-resolution diffusion tensor imaging. RESULTS: The differences between the two states of contraction were most pronounced in the endocardium where the E3-angle decreased from 78.6° to 24.8° in the LV and from 82.6° to 68.6° in the RV. No significant change in neither the helical nor the transmural angle was found in the cardiomyocytes of the RV. In the endocardium of the LV, however, the helical angle increased from 35.4° to 47.8° and the transmural angle increased from 3.1° to 10.4°. CONCLUSION: The entire myocardium rearranges through the cardiac cycle with the change in the orientation of the aggregations of cardiomyocytes being the predominant mediator of myocardial wall thickening. Interestingly, differences also exist between the RV and LV, which helps in the explanation of the different physiological capabilities of the ventricles.


Subject(s)
Diffusion Tensor Imaging , Heart Ventricles/diagnostic imaging , Myocardial Contraction , Myocytes, Cardiac/physiology , Ventricular Function, Left , Ventricular Function, Right , Ventricular Remodeling , Animals , Female , Heart Ventricles/cytology , Predictive Value of Tests , Sus scrofa , Time Factors
16.
J Anat ; 235(4): 697-705, 2019 10.
Article in English | MEDLINE | ID: mdl-31206661

ABSTRACT

The manner of packing together of the cardiomyocytes within the walls of the cardiac ventricles has now been investigated for over half a millennium. In 1669, Lower dissected the ventricular mass, likening the arrangement to skeletal musculature, in the form of a myocardial band extending between the right and left atrioventricular junctions. Pettigrew subsequently showed obvious helical arrangements to be evident within the ventricular walls, but emphasised that the cardiomyocytes were attached to each other, and could not justifiably be compared with skeletal cardiomyocytes. Torrent-Guasp then reactivated the notion that the ventricular mass was formed of a solitary band. Unlike Lower, he dissected the band as extending between the pulmonary to the aortic roots. Multiple investigations conducted using gross dissection and histology, and more recently diffusion tensor magnetic resonance imaging and computed tomographic analysis, have shown an absence of any anatomical boundaries within the walls that might permit the mass uniformly to be dissected so as to reveal the band. A response to a recent letter to the Journal, nonetheless, claimed that the dissections had been validated by clinicians interpreting the findings so as to provide an explanation for ventricular cardiodynamics, arguing that the findings provided a suitable anatomical model for this purpose. Anatomical models, however, are of no value unless they are anatomically correct. In this review, therefore, we summarise the evidence showing that the cardiomyocytes making up the ventricular walls, rather than forming a ventricular myocardial band, are instead aggregated together to form a three-dimensional myocardial mesh.


Subject(s)
Heart Ventricles/cytology , Myocytes, Cardiac/cytology , Humans
17.
J Fish Biol ; 95(2): 367-378, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30900244

ABSTRACT

The main objective of this study was to investigate if egg size (mass) at spawning is invariant for Scotia-Fundy summer and autumn (SFSH) and Icelandic summer (ISSH) spawning herring Clupea harengus. Oocyte dry mass measurements for SFSH females collected in 2001 and ISSH females collected in 1999 and 2000 showed a large variation. Difference in egg dry mass among fish was found to vary by as much as twofold in each stock. For ISSH, variation in egg mass was also apparent from oocyte volume measurements made jointly with a histological examination of the ovaries. Approximately 20% of the variation in egg mass could be explained by maternal whole-body mass or total length, indicating that length or age composition in the stocks can potentially influence the recruitment success. This implies that fisheries management strategies should aim to maintain a broad range in age composition.


Subject(s)
Fisheries/trends , Fishes/physiology , Age Factors , Analysis of Variance , Animals , Female , Fertility , Fisheries/organization & administration , Fishes/anatomy & histology , Iceland , Least-Squares Analysis , Linear Models , Nova Scotia , Oocytes/ultrastructure , Ovary/anatomy & histology , Seasons , Species Specificity
18.
J Urol ; 201(4): 751-758, 2019 04.
Article in English | MEDLINE | ID: mdl-30366023

ABSTRACT

PURPOSE: Preoperative counseling incorporating the best case, the worst case and the most likely outcome scenarios aid patient decision making. This information is not readily available for prostate cancer counseling because most patient reported outcomes are presented as averages, which minimize individual patient experiences. Using the EPIC (Expanded Prostate Index Composite) we present data to characterize the best case and the worst case after prostatectomy. MATERIALS AND METHODS: The EPIC bowel, urinary irritation, continence and sexual function scores were measured in 1,418 men stratified by baseline function who underwent prostatectomy. Patient level functional trajectories were modeled using a Bayesian hierarchical model. The 5-year best and worst case outcomes were defined as the upper 95th and the lower 5th percentiles, respectively. RESULTS: Five years after surgery in patients with good baseline urinary continence the best case was a score of 100.0 (95% credible interval 100.0-100.0) and the worst case was 54.4 (95% credible interval 42.2-63.7). Among men with good baseline sexual function who underwent nerve sparing surgery the best case was 83.9 points (95% credible interval 74.1-93.1) and the worst case was 17.6 (95% credible interval 7.5-26.1). The differences between best and worst case for bowel and urinary irritation were relatively small (11.4 and 13.6 points, respectively). CONCLUSIONS: Prostatectomy exerted a minimal negative impact on urinary irritation and bowel function with minimal variability. There was a larger range in patient experience for urinary continence and sexual function with most patients experiencing a significant functional decline. Future studies of best and worst case outcomes of multiple treatment modalities may provide valuable information for shared decision making in prostate cancer treatment.


Subject(s)
Decision Making , Directive Counseling , Patient Reported Outcome Measures , Prostatectomy , Prostatic Neoplasms/surgery , Aged , Humans , Male , Middle Aged , Prostatectomy/methods
19.
Mol Cancer Ther ; 18(3): 726-729, 2019 03.
Article in English | MEDLINE | ID: mdl-30587554

ABSTRACT

There are many treatment options available for men with metastatic castration-resistant prostate cancer (mCRPC). Yet, biomarkers predictive of differential response to treatment are currently unavailable. A recent translational study suggested that SLCO2B1 genotype could predict response to abiraterone acetate for men with advanced prostate cancer. Here, we investigate whether germline variants in SLCO2B1 are predictive of response to first-line abiraterone acetate in men with new mCRPC. Clinical data and samples were analyzed from a prospective prostate cancer registry at the University of Utah (Salt Lake City, UT). Genotyping was performed using the Illumina OmniExpress genotyping platform. Primary endpoint was progression-free survival (PFS) on first-line abiraterone acetate in men with mCRPC. We performed a prespecified multivariate Cox regression analysis to assess the independent predictive value of rs12422149 and rs1789693 on PFS on abiraterone acetate. Of 401 men with advanced prostate cancer genotyped, 323 were homozygous wild-type for rs12422149 (80.5%), 74 were heterozygous (18.5%), and 4 were homozygous variant (1.0%). In a multivariate analysis of 79 men treated with first-line abiraterone acetate for mCRPC, men heterozygous for rs12422149 had significantly improved median PFS compared with the homozygous wild-type group (8.9 months vs. 6.3 months; HR, 0.46; 95% confidence interval, 0.23-0.94; P = 0.03). No significant difference in median PFS was seen by rs1789693 genotype. In this first clinical validation of translational data reported by Mostaghel and colleagues, germline variant alleles in rs12422149 of SLCO2B1 are common and predict improved response to first-line abiraterone acetate in men with mCRPC.


Subject(s)
Abiraterone Acetate/pharmacology , Organic Anion Transporters/genetics , Prednisone/pharmacology , Prostatic Neoplasms, Castration-Resistant/drug therapy , Aged , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Cell Line, Tumor , Disease-Free Survival , Genotype , Germ-Line Mutation/genetics , Humans , Male , Middle Aged , Neoplasm Grading , Neoplasm Metastasis , Polymorphism, Single Nucleotide/genetics , Prostate/metabolism , Prostate/pathology , Prostatic Neoplasms, Castration-Resistant/genetics , Prostatic Neoplasms, Castration-Resistant/pathology
20.
J Cell Sci ; 132(2)2019 01 16.
Article in English | MEDLINE | ID: mdl-30559249

ABSTRACT

Metazoans contain two homologs of the Gcn5-binding protein Ada2, Ada2a and Ada2b, which nucleate formation of the ATAC and SAGA complexes, respectively. In Drosophila melanogaster, there are two splice isoforms of Ada2b: Ada2b-PA and Ada2b-PB. Here, we show that only the Ada2b-PB isoform is in SAGA; in contrast, Ada2b-PA associates with Gcn5, Ada3, Sgf29 and Chiffon, forming the Chiffon histone acetyltransferase (CHAT) complex. Chiffon is the Drosophila ortholog of Dbf4, which binds and activates the cell cycle kinase Cdc7 to initiate DNA replication. In flies, Chiffon and Cdc7 are required in ovary follicle cells for gene amplification, a specialized form of DNA re-replication. Although chiffon was previously reported to be dispensable for viability, here, we find that Chiffon is required for both histone acetylation and viability in flies. Surprisingly, we show that chiffon is a dicistronic gene that encodes distinct Cdc7- and CHAT-binding polypeptides. Although the Cdc7-binding domain of Chiffon is not required for viability in flies, the CHAT-binding domain is essential for viability, but is not required for gene amplification, arguing against a role in DNA replication.


Subject(s)
Drosophila Proteins/metabolism , Egg Proteins/metabolism , Histone Acetyltransferases/metabolism , Histones/metabolism , Acetylation , Animals , Cell Line , Drosophila Proteins/genetics , Drosophila melanogaster , Egg Proteins/genetics , Histone Acetyltransferases/genetics , Histones/genetics , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism
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