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1.
Mol Psychiatry ; 28(6): 2301-2311, 2023 06.
Article in English | MEDLINE | ID: mdl-37173451

ABSTRACT

BACKGROUND: Alterations in brain connectivity may underlie neuropsychiatric conditions such as schizophrenia. We here assessed the degree of convergence of frontostriatal fiber projections in 56 young adult healthy controls (HCs) and 108 matched Early Psychosis-Non-Affective patients (EP-NAs) using our novel fiber cluster analysis of whole brain diffusion magnetic resonance imaging tractography. METHODS: Using whole brain tractography and our fiber clustering methodology on harmonized diffusion magnetic resonance imaging data from the Human Connectome Project for Early Psychosis we identified 17 white matter fiber clusters that connect frontal cortex (FCtx) and caudate (Cd) per hemisphere in each group. To quantify the degree of convergence and, hence, topographical relationship of these fiber clusters, we measured the inter-cluster mean distances between the endpoints of the fiber clusters at the level of the FCtx and of the Cd, respectively. RESULTS: We found (1) in both groups, bilaterally, a non-linear relationship, yielding convex curves, between FCtx and Cd distances for FCtx-Cd connecting fiber clusters, driven by a cluster projecting from inferior frontal gyrus; however, in the right hemisphere, the convex curve was more flattened in EP-NAs; (2) that cluster pairs in the right (p = 0.03), but not left (p = 0.13), hemisphere were significantly more convergent in HCs vs EP-NAs; (3) in both groups, bilaterally, similar clusters projected significantly convergently to the Cd; and, (4) a significant group by fiber cluster pair interaction for 2 right hemisphere fiber clusters (numbers 5, 11; p = .00023; p = .00023) originating in selective PFC subregions. CONCLUSIONS: In both groups, we found the FCtx-Cd wiring pattern deviated from a strictly topographic relationship and that similar clusters projected significantly more convergently to the Cd. Interestingly, we also found a significantly more convergent pattern of connectivity in HCs in the right hemisphere and that 2 clusters from PFC subregions in the right hemisphere significantly differed in their pattern of connectivity between groups.


Subject(s)
Psychotic Disorders , White Matter , Young Adult , Humans , Healthy Volunteers , Cadmium , White Matter/pathology , Brain/pathology , Psychotic Disorders/diagnostic imaging , Psychotic Disorders/pathology
2.
J Exp Orthop ; 9(1): 115, 2022 Dec 02.
Article in English | MEDLINE | ID: mdl-36459283

ABSTRACT

PURPOSE: The aim of this study was to determine the frequency of secondary surgery following anterior cruciate ligament (ACL) repair with suture tape augmentation in comparison to conventional hamstring ACL reconstruction. We hypothesised that there would be no differences between the groups. METHODS: This was a retrospective comparison study of patients undergoing ACL surgery between September 2011 and April 2018. Two hundred and 73 patients underwent ACL reconstruction using hamstring autograft. During the same timeframe, 137 patients with an acute proximal ACL rupture underwent ACL repair with suture tape augmentation. One patient was lost to follow-up in the ACL reconstruction group leaving 272 patients (99.6%) for the final analysis. In the ACL repair group, three patients were lost to follow-up leaving 134 patents (97.8%) for the final analysis. Secondary surgery was identified by contacting the patients by email/telephone and reviewing patient notes at the time of this analysis. RESULTS: Re-rupture occurred in 32 patients (11.8%) in the ACL reconstruction group compared to 22 patients (16.4%) in the ACL repair group (p = 0.194). Contralateral ACL rupture occurred in four patients (1.5%) in the ACL reconstruction group compared to three patients (2.2%) in the ACL repair group (p = 0.224). In the ACL reconstruction group, nine patients (3.3%) required secondary meniscal surgery whilst five patients (3.7%) required meniscal surgery in the ACL repair group (p = 0.830). Seven other operations were performed in the ACL reconstruction group (2.6%) compared to three other operations in the ACL repair group (2.2%) (p = 0.374). The overall number of patients undergoing secondary surgery in the ACL reconstruction group was 52 (19.1%) in comparison to 30 (22.4%) in the ACL repair group (p = 0.114). CONCLUSION: ACL repair with suture tape augmentation for acute proximal ruptures demonstrated comparable rates of secondary surgery with hamstring ACL reconstruction.

3.
Cereb Cortex ; 31(12): 5308-5318, 2021 10 22.
Article in English | MEDLINE | ID: mdl-34180506

ABSTRACT

To assess normal organization of frontostriatal brain wiring, we analyzed diffusion magnetic resonance imaging (dMRI) scans in 100 young adult healthy subjects (HSs). We identified fiber clusters intersecting the frontal cortex and caudate, a core component of associative striatum, and quantified their degree of deviation from a strictly topographic pattern. Using whole brain dMRI tractography and an automated tract parcellation clustering method, we extracted 17 white matter fiber clusters per hemisphere connecting the frontal cortex and caudate. In a novel approach to quantify the geometric relationship among clusters, we measured intercluster endpoint distances between corresponding cluster pairs in the frontal cortex and caudate. We show first, the overall frontal cortex wiring pattern of the caudate deviates from a strictly topographic organization due to significantly greater convergence in regionally specific clusters; second, these significantly convergent clusters originate in subregions of ventrolateral, dorsolateral, and orbitofrontal prefrontal cortex (PFC); and, third, a similar organization in both hemispheres. Using a novel tractography method, we find PFC-caudate brain wiring in HSs deviates from a strictly topographic organization due to a regionally specific pattern of cluster convergence. We conjecture cortical subregions projecting to the caudate with greater convergence subserve functions that benefit from greater circuit integration.


Subject(s)
Diffusion Tensor Imaging , White Matter , Brain/diagnostic imaging , Cluster Analysis , Diffusion Tensor Imaging/methods , Healthy Volunteers , Humans , Neural Pathways/diagnostic imaging , Neural Pathways/pathology , White Matter/diagnostic imaging , Young Adult
4.
BMC Geriatr ; 18(1): 9, 2018 01 11.
Article in English | MEDLINE | ID: mdl-29325531

ABSTRACT

BACKGROUND: The potential harms of some medications may outweigh their potential benefits (inappropriate medication use). Despite recommendations to avoid the use of potentially inappropriate medications (PIMs) in older adults, the prevalence of PIM use is high in different settings including residential aged care. However, it remains unclear what the costs of these medications are in this setting. The main objective of this study was to determine the costs of PIMs in older adults living in residential care. A secondary objective was to examine if there was a difference in costs of PIMs in a home-like model of residential care compared to an Australian standard model of care. METHODS: Participants included 541 participants from the Investigation Services Provided in the Residential Environment for Dementia (INSPIRED) Study. The INSPIRED study is a cross-sectional study of 17 residential aged care facilities in Australia. 12 month medication costs were determined for the participants and PIMs were identified using the 2015 updated Beers Criteria for older adults. RESULTS: Of all of the medications dispensed in 1 year, 15.9% were PIMs and 81.4% of the participants had been exposed to a PIM. Log-linear models showed exposure to a PIM was associated with higher total medication costs (Adjusted ß = 0.307, 95% CI 0.235 to 0.379, p < 0.001). The mean proportion (±SD) of medication costs that were spent on PIMs in 1 year was 17.5% (±17.8) (AUD$410.89 ± 479.45 per participant exposed to a PIM). The largest PIM costs arose from proton-pump inhibitors (34.4%), antipsychotics (21.0%) and benzodiazepines (18.7%). The odds of incurring costs from PIMs were 52% lower for those residing in a home-like model of care compared to a standard model of care. CONCLUSIONS: The use of PIMs for older adults in residential care facilities is high and these medications represent a substantial cost which has the potential to be lowered. Further research should investigate whether medication reviews in this population could lead to potential cost savings and improvement in clinical outcomes. Adopting a home-like model of residential care may be associated with reduced prevalence and costs of PIMs.


Subject(s)
Health Care Costs , Inappropriate Prescribing/economics , Potentially Inappropriate Medication List/economics , Potentially Inappropriate Medication List/statistics & numerical data , Residential Facilities/economics , Aged , Aged, 80 and over , Assisted Living Facilities/economics , Assisted Living Facilities/trends , Australia/epidemiology , Cross-Sectional Studies , Dementia/drug therapy , Dementia/economics , Dementia/epidemiology , Female , Health Care Costs/trends , Humans , Inappropriate Prescribing/trends , Male , Potentially Inappropriate Medication List/trends , Prevalence , Residential Facilities/trends , Retrospective Studies
5.
Bone Marrow Transplant ; 52(4): 561-566, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28067870

ABSTRACT

In an otherwise eligible patient with relapsed lymphoma, inadequate mobilization of hematopoietic stem cells (HSCs) is a limiting factor to proceeding with an autologous hematopoietic cell transplantation (auto-HCT). Multiple strategies have been used to mobilize an adequate number of HSCs with no obvious front-line strategy. We report a single institutional experience mobilizing HSCs using four different approaches in lymphoma patients. We prospectively collected mobilization outcomes on patients planned to undergo auto-HCT at Ohio State University. We report results of first mobilization attempts for all relapsed or refractory lymphoma patients between 2008 and 2014. We identified 255 lymphoma patients who underwent mobilization for planned auto-HCT. The 255 lymphoma patients underwent the following front line mobilization strategies: 95 (37%) G-CSF alone, 38 (15%) chemomobilization (G-CSF+chemotherapy), 97 (38%) preemptive day 4 plerixafor, and 25 (10%) rescue day 5 plerixafor. As expected, there were significant differences between cohorts including age, comorbidity indices, histology, and amount of prior chemotherapy. After controlling for differences between groups, the odds of collecting 2 × 106/kg HSCs on the first day of collection and 5 × 106/kg HSCs in total was the highest in the cohort undergoing chemomobilization. In conclusion, our experience highlights the effectiveness of chemomobilization.


Subject(s)
Hematopoietic Stem Cell Mobilization/methods , Hematopoietic Stem Cell Transplantation/methods , Lymphoma/therapy , Adult , Aged , Antigens, CD34/analysis , Antineoplastic Agents/administration & dosage , Benzylamines , Cell Count , Cyclams , Female , Granulocyte Colony-Stimulating Factor/administration & dosage , Hematopoietic Stem Cell Mobilization/standards , Hematopoietic Stem Cells/cytology , Heterocyclic Compounds/administration & dosage , Humans , Lymphoma/mortality , Male , Middle Aged , Prospective Studies , Transplantation, Autologous , Young Adult
6.
Andrology ; 2(6): 884-91, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25280067

ABSTRACT

Oligoasthenoteratozoospermia (OAT) is a phenotype frequently observed in infertile men, and is defined by low spermatozoa number, abnormal spermatozoa morphology and poor motility. We previously showed that a mutation in the Katnb1 gene in mice causes infertility because of OAT. The KATNB1 gene encodes an accessory subunit of the katanin microtubule-severing enzyme complex; this accessory subunit is thought to modulate microtubule-severing location and activity. We hypothesized that KATNB1 may play a role in human spermatogenesis and that genetic variants in KATNB1 could be associated with OAT in humans. Using immunostaining, we defined the localization of the KATNB1 protein in human testes. KATNB1 was present during spermatid development, and in particular localized to the microtubules of the manchette, a structure required for sperm head shaping. To assess a potential association between genetic variants in the KATNB1 gene and infertile men with OAT, we performed direct sequencing of genomic DNA samples from 100 OAT infertile and 100 proven fertile men. Thirty-seven KATNB1 variants were observed, five of which had not previously been described. Ten variants were present only in OAT men, however, statistical analysis did not reveal a significant association with fertility status. Our results suggest that variants in the KATNB1 gene are not commonly associated with OAT infertility in Australian men.


Subject(s)
Adenosine Triphosphatases/genetics , Fertility , Infertility, Male/metabolism , Testis/metabolism , Adenosine Triphosphatases/chemistry , Amino Acid Sequence , Animals , Genetic Variation , Humans , Katanin , Male , Molecular Sequence Data , Sequence Homology, Amino Acid
7.
Bone Marrow Transplant ; 49(8): 1052-5, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24797182

ABSTRACT

In an otherwise eligible patient, inadequate mobilization of PBSCs is a limiting factor to proceeding with an auto-ASCT. In such situations, plerixafor is commonly added to improve PBSC collection yields along with cytokine (G-CSF alone) or chemomobilization (chemotherapy+G-CSF). Individually, both strategies are proven to be safe and effective. Here we report six patients who underwent successful mobilization with combination chemomobilization plus plerixafor after upfront failure of cytokine mobilization plus plerixafor. The median CD34(+) cell yield after chemomobilization was 2.48 × 10(6)/kg (range 0.99-8.49) after receiving one to two doses of plerixafor. All patients subsequently underwent ASCT without major unforeseen toxicities and engrafted successfully. No significant delays in time to neutrophil recovery were observed. Our experience highlights the safety and effectiveness of chemomobilization with plerixafor after G-CSF plus plerixafor (G+P) failure and suggests this is a viable salvage strategy after initial failed G+P mobilization.


Subject(s)
Anti-HIV Agents/administration & dosage , Hematopoietic Stem Cell Mobilization/methods , Heterocyclic Compounds/administration & dosage , Lymphoma/therapy , Peripheral Blood Stem Cell Transplantation , Adult , Aged , Autografts , Benzylamines , Cyclams , Female , Humans , Lymphoma/blood , Male , Middle Aged
8.
Schizophr Res ; 151(1-3): 175-84, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24210871

ABSTRACT

Research utilizing visual event-related brain potentials (ERPs) has demonstrated that reduced P300 amplitude and prolonged latency may qualify as a biological marker (biomarker) for schizophrenia (SZ). We examined P300 characteristics in response inhibition among three putatively distinct psychopathology groups including schizophrenia (SZ), bipolar I disorder (BD) and schizoaffective disorder (SA) in comparison with healthy controls (CT) to determine their electrophysiological distinctiveness. In two separate studies, deficits in response inhibition indexed by the P300 component were investigated using a lateralized Go/NoGo task. We hypothesized that deficits in response inhibition would be present and distinctive among the groups. In both studies, SZ showed response inhibition deficits as measured by P300 when stimuli were presented to the right visual field. In Study 2, delayed cognitive stimulus evaluation was observed in BD as indexed by prolonged P300 latency for NoGo trials. Six selected NoGo P300 variables out of thirty six NoGo P300 variables (18 amplitude, 18 latency) correctly classified SZ (79%), SA (64%) in Study 1 and seven variables selected in Study 2 classified CT (80%), and SZ (61%), BD (67%) and CT (68%) with the accuracy higher than chance level (33%). The findings suggest that distinct P300 features in response inhibition may be biomarkers with the capacity to distinguish BD and SZ, although SA was not clearly distinguishable from SZ and CT.


Subject(s)
Bipolar Disorder/diagnosis , Event-Related Potentials, P300/physiology , Inhibition, Psychological , Psychotic Disorders/diagnosis , Schizophrenia/diagnosis , Adult , Bipolar Disorder/physiopathology , Decision Making , Electroencephalography , Female , Functional Laterality , Humans , Male , Middle Aged , Neuropsychological Tests , Photic Stimulation , Psychiatric Status Rating Scales , Psychotic Disorders/physiopathology , Reaction Time , Schizophrenia/physiopathology
9.
AIDS Care ; 24(8): 1028-38, 2012.
Article in English | MEDLINE | ID: mdl-22519680

ABSTRACT

Our research aims were to: (1) assess the prevalence of two condom use problems: breakage or slippage and partial use (delayed application or early removal) among men who have sex with men (MSM) seeking services in urban US STD clinics; and (2) examine the association between these condom use problems and participant, partner and partnership characteristics. Analysis was restricted to HIV-negative MSM who reported having anal sex at least once in the preceding 3 months and who completed both the baseline and 3 month follow-up assessments. Two models were fitted using the generalized estimating equations (GEE) approach. A total of 263 MSM (median age=32 years) reported 990 partnerships. Partnerships with no condom use 422 (42.6%) were excluded. Thus, 207 MSM and 568 partnerships were included. Among condom users, 100% use was reported within 454 partnerships (79.9%) and <100% within 114 (20.1%), and 21(3.7%) reported both condom use problems, 25 (4.4%) reported only breakage, 67 (11.8%) reported only partial use, and 455 (80.1%) reported no errors. The breakage or slippage and partial use rates per condom used were 3.4% and 11.2%, respectively. A significantly higher rate of breakage or slippage occurred among non-main partnerships. Characteristics associated with increased odds for condom breakage or slippage were: lower education level (OR=2.78; CI: 1.1-7.5), non-main partner status (OR=4.1; CI: 1.5-11.7), and drunk or high during sex (OR=2.0; CI: 1.1-3.8), and for partial use: lower education level (OR=2.6; CI: 1.0-6.6), perceived partner sexually transmitted infections (STI) risk (OR=2.4; CI: 1.3-4.2), and inconsistent condom use (OR=3.7; CI: 2.0-6.6). A high percentage of MSM partnerships reported no condom use and among condom users, a sizable proportion did not use them consistently or correctly. MSM may benefit from interventions designed to increase proficiency for condom use with a particular focus on the behaviors of inconsistent and partial condom use.


Subject(s)
Condoms/statistics & numerical data , Equipment Failure/statistics & numerical data , Homosexuality, Male/statistics & numerical data , Sexual Behavior , Adult , HIV Seronegativity , Humans , Male , United States/epidemiology , Urban Health
10.
Eur J Neurol ; 19(2): 307-11, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21899662

ABSTRACT

BACKGROUND: Alemtuzumab (CD52-specific humanized monoclonal antibody) was found to be an effective therapy for treatment-naive patients with relapsing-remitting multiple sclerosis. OBJECTIVE: Evaluate alemtuzumab's effects in patients with treatment-refractory relapsing-remitting multiple sclerosis. METHODS: Forty-five relapsing-remitting multiple sclerosis patients who experienced ≥2 relapses during 2 years prior to the study entry whilst receiving interferon therapy were administered 24 mg i.v. alemtuzumab/day for 5 days at baseline and 3 days 12 months later. Patients received premedication with 1 g i.v. methylprednisolone on days 1-3 at both times. RESULTS: After 2-year follow-up, the annualized relapse rate was reduced by 94% compared to pre-treatment levels, from 1.6 (2 years prior to treatment) to 0.17 for the 2 years following (P<0.0001). Moreover, 86% of patients showed stable or improved scores on the Expanded Disability Status Scale, and only 1 experienced an increase in disability lasting ≥6 months. The majority (70-88%) showed stable or improved leg, arm and cognitive function as measured by the Multiple Sclerosis Functional Composite. Serious adverse events observed in single patients were transient neutropenia and pneumonia, pulmonary emboli and deep vein thrombosis. Five patients developed clinical thyroid disorders but no opportunistic infections or cases of immune thrombocytopenic purpura were observed. CONCLUSIONS: Alemtuzumab effectively reduced relapse rates and improved clinical scores in patients with active relapsing-remitting multiple sclerosis not controlled by interferon therapy.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Adjuvants, Immunologic/therapeutic use , Adolescent , Adult , Alemtuzumab , Female , Follow-Up Studies , Humans , Male , Methylprednisolone/therapeutic use , Middle Aged , Treatment Outcome
11.
Sci Justice ; 50(4): 195-9, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21075298

ABSTRACT

Two experimental studies were undertaken to investigate the processes of reincorporation and redistribution of trace evidence on garments when worn by a suspect or a victim (reincorporation) or after the garments have been seized and packaged for subsequent forensic analysis (redistribution). The first experiment utilised UV powder, an established proxy for geoforensic trace particulates and the second experiment utilised daffodil pollen transferred onto garments under conditions that mimicked forensic reality. It was demonstrated that reincorporation of trace particulates occurs from upper to lower parts of the same garment and also from upper garments to lower garments. Reincorporation also occurred to all areas of the lower garments, however the highest concentration of particulates was found to be the lap area of the jeans. Particulates also tended to be preserved around technical details such as stitching or relief design features of the garments. Thus the decay of particulates after a contact has been made does not necessarily involve a loss of those particulates from the entire system. These findings have implications for the interpretation of trace evidence when seeking to establish the source of initial contacts or the chronology of pertinent events. The second study demonstrated that folding and packaging items of clothing leads to a redistribution of any trace particulate evidence that is present thereby eliciting an alteration in the spatial distribution of that evidence. There is therefore a necessity to take the context of trace evidence into account and also to follow protocols that are sensitive to these aspects of trace evidence behaviour as a failure to do so may have consequences for the correct interpretation of such evidence.


Subject(s)
Clothing , Particulate Matter/analysis , Pollen , Soil/analysis , Forensic Sciences , Humans , Microscopy, Ultraviolet
12.
Aliment Pharmacol Ther ; 24(1): 95-9, 2006 Jul 01.
Article in English | MEDLINE | ID: mdl-16803607

ABSTRACT

BACKGROUND: Motilin receptor stimulation with erythromycin has been shown to have a prokinetic effect on gall-bladder motility in human beings. AIM: To find out whether oral clarithromycin has similar prokinetic activity to erythromycin on fasting and postprandial gall-bladder emptying in normal humans and those with gall-stone disease. METHODS: In a blinded two-way crossover study clarithromycin 500 mg and a placebo were administered to 10 normal subjects and 10 subjects with gall-stone disease. Gall-bladder volumes were assessed in the fasting and postprandial state. RESULTS: Fasting volumes were significantly less following clarithromycin administration in both normal subjects and subjects with gall-stones compared with placebo (12.1 +/- 1.8 mL vs. 17.8 +/- 2.0 mL, P < 0.05 and 16.7 +/- 2 mL vs. 26.8 +/- 7.2 mL, P < 0.02, mean +/- S.E.M). Postprandial volumes were also significantly less following clarithromycin administration. Ejection fraction significantly increased following clarithromycin in both normal subjects (66 +/- 5.8% vs. 37 +/- 5.9%, P = 0.02) and subjects with gall-stones (45 +/- 3.2 vs. 20 +/- 1.6%, P < 0.02). CONCLUSION: Clarithromycin enhances both fasting and postprandial gall-bladder contraction in normal humans and also in those with gall-stone disease.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Clarithromycin/administration & dosage , Gallbladder Emptying/drug effects , Gallstones/physiopathology , Administration, Oral , Adult , Cross-Over Studies , Double-Blind Method , Fasting/physiology , Female , Humans , Male , Middle Aged , Postprandial Period
13.
AJNR Am J Neuroradiol ; 27(5): 1032-6, 2006 May.
Article in English | MEDLINE | ID: mdl-16687538

ABSTRACT

BACKGROUND/PURPOSE: Despite its potential for visualizing white matter fiber tracts in vivo, diffusion tensor tractography has found only limited applications in clinical research in which specific anatomic connections between distant regions need to be evaluated. We introduce a robust method for fiber clustering that guides the separation of anatomically distinct fiber tracts and enables further estimation of anatomic connectivity between distant brain regions. METHODS: Line scanning diffusion tensor images (LSDTI) were acquired on a 1.5T magnet. Regions of interest for several anatomically distinct fiber tracts were manually drawn; then, white matter tractography was performed by using the Runge-Kutta method to interpolate paths (fiber traces) following the major directions of diffusion, in which traces were seeded only within the defined regions of interest. Next, a fully automatic procedure was applied to fiber traces, grouping them according to a pairwise similarity function that takes into account the shapes of the fibers and their spatial locations. RESULTS: We demonstrated the ability of the clustering algorithm to separate several fiber tracts which are otherwise difficult to define (left and right fornix, uncinate fasciculus and inferior occipitofrontal fasciculus, and corpus callosum fibers). CONCLUSION: This method successfully delineates fiber tracts that can be further analyzed for clinical research purposes. Hypotheses regarding specific fiber connections and their abnormalities in various neuropsychiatric disorders can now be tested.


Subject(s)
Brain/anatomy & histology , Diffusion Magnetic Resonance Imaging , Adolescent , Adult , Diffusion Magnetic Resonance Imaging/methods , Humans , Middle Aged
14.
J Endocrinol ; 189(2): 381-95, 2006 May.
Article in English | MEDLINE | ID: mdl-16648304

ABSTRACT

Spermatogenesis is dependent on the ability of Sertoli cells to form mature junctions that maintain a unique environment within the seminiferous epithelium. Adjacent Sertoli cells form a junctional complex that includes classical adherens junctions and testis-specific ectoplasmic specialisations (ES). The regulation of inter-Sertoli cell junctions by the two main endocrine regulators of spermatogenesis, FSH and testosterone, is unclear. This study aimed to investigate the effects of FSH and testosterone on inter-Sertoli cell adherens junctions (as determined by immunolocalisation of cadherin, catenin and actin) and ES junctions (as determined by immunolocalisation of espin, actin and vinculin) in cultured immature Sertoli cells and GnRH-immunised adult rat testes given FSH or testosterone replacement in vivo. When hormones were absent in vitro, adherens junctions formed as discrete puncta between interdigitating, finger-like projections of Sertoli cells, but ES junctions were not present. The adherens junction puncta included actin filaments that were oriented perpendicularly to the Sertoli cell plasma membrane, but were not associated with the intermediate filament protein vimentin. When FSH was added in vitro, ES junctions formed, and adjacent adherens junction puncta fused into extensive adherens junction belts. After hormone suppression in vivo, ES junctions were absent, while FSH replacement restored ES junctions, as confirmed by electron microscopy and confocal analysis of ES-associated proteins. Testosterone alone did not affect adherens junctions or ES in vitro or in vivo. We conclude that FSH can regulate the formation of ES junctions and stimulate the organisation and orientation of extensive adherens junctions in Sertoli cells.


Subject(s)
Adherens Junctions/physiology , Follicle Stimulating Hormone/physiology , Testis/physiology , Actins/analysis , Animals , Cadherins/analysis , Cells, Cultured , Fertility Agents, Female/immunology , Gonadotropin-Releasing Hormone/immunology , Immunohistochemistry/methods , Male , Microfilament Proteins/analysis , Microscopy, Confocal/methods , Rats , Rats, Sprague-Dawley , Sertoli Cells/immunology , Sertoli Cells/physiology , Testis/immunology , Testosterone/physiology , Vinculin/analysis , beta Catenin/analysis
16.
Reprod Domest Anim ; 38(3): 233-5, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12753560

ABSTRACT

The mare exhibits nocturnal uterine contractions in the last 6 days of gestation. It is hypothesized that estradiol 17beta (O17beta) may be associated with the nightly increase in uterine contractions. The 24-h secretion pattern of plasma O17beta was measured in 3 pony mares in late gestation to identify changes in release as the mare neared parturition. Blood was collected weekly at 08:00 hours beginning on day 240 and every third day from day 330 until delivery. Serial blood samples were collected from each mare every 30-min for 24-h beginning on gestation day 310 and every sixth day thereafter until parturition. Concentrations of O17beta were elevated at night with lowest concentrations occurring directly before sunset (p < 0.01). The natural log of the variance was increased at sunset (p < 0.01) and was decreased during the 6-h period immediately after sunrise. This pattern was especially evident in the 6 days that preceded parturition. The contrast between nocturnal and daytime concentrations of O17beta in the last 6 days of gestation may contribute to night-time delivery in the mare.


Subject(s)
Estradiol/blood , Horses/blood , Pregnancy, Animal/blood , Uterine Contraction/physiology , Animals , Circadian Rhythm , Female , Pregnancy
17.
J Endocrinol ; 176(3): 393-403, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12630924

ABSTRACT

Testosterone is metabolised to the more potent androgen, dihydrotestosterone, by the 5alpha-reductase (5alphaR) enzyme. We previously showed that 5alpha-reduced androgens are important for maintaining androgen action on rat spermatogenesis when testicular testosterone concentrations are reduced. This study investigated expression and activity of the 5alphaR isoforms, type 1 (5alphaR-1) and type 2 (5alphaR-2), in the rat during hormone manipulation in order to understand the factors that regulate the testicular concentration of 5alphaR and testicular 5alpha-reduced androgen biosynthesis. Testicular 5alphaR-1 and 5alphaR-2 mRNA and enzyme activity were measured by real-time PCR and specific enzyme assays respectively. Hormone levels were first suppressed using two models of gonadotrophin suppression: testosterone and oestradiol treatment (LH/testosterone deficiency) or GnRH immunisation (LH/testosterone and FSH deficiency). Hormones were then either restored or suppressed for 6 days by a variety of hormonal treatments. 5alphaR-1 mRNA and enzyme activity increased when testosterone was suppressed, yet restoration of testosterone decreased 5alphaR-1 mRNA and enzyme activity, suggesting that testosterone negatively regulates 5alphaR-1. suppression of FSH decreased 5alphaR-1 mRNA yet FSH administration increased 5alphaR-1 mRNA, but no changes in 5alphaR-1 activity were observed within the 6 day period. In contrast to 5alphaR-1, testosterone did not affect the testicular concentration of 5alphaR-2 mRNA or activity, but there was evidence for modulation of 5alphaR-2 activity by FSH. Measurement of testicular androgens revealed that 5alphaR-1 was primarily responsible for the production of 5alpha-reduced metabolites. It is concluded that the 5alphaR isoforms in rat testis are differentially regulated by testosterone and FSH: testosterone negatively regulated 5alphaR-1 mRNA and enzyme activity but had no affect on 5alphaR-2, whereas FSH positively regulated 5alphaR-1 mRNA and appeared to regulate 5alphaR-2.


Subject(s)
3-Oxo-5-alpha-Steroid 4-Dehydrogenase/metabolism , Follicle Stimulating Hormone/metabolism , Isoenzymes/metabolism , Testis/enzymology , Testosterone/metabolism , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/analysis , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/genetics , Androgen Antagonists/pharmacology , Animals , Dihydrotestosterone/metabolism , Drug Implants , Estradiol/pharmacology , Flutamide/pharmacology , Follicle Stimulating Hormone/immunology , Gonadotropin-Releasing Hormone/immunology , Gonadotropin-Releasing Hormone/pharmacology , Immune Sera/pharmacology , Immunization , Isoenzymes/analysis , Isoenzymes/genetics , Luteinizing Hormone/metabolism , Male , Models, Animal , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Recombinant Proteins/pharmacology , Testis/drug effects , Testosterone/antagonists & inhibitors
18.
Aliment Pharmacol Ther ; 16(10): 1801-3, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12269974

ABSTRACT

BACKGROUND: The effects of alpha- and beta-adrenergic agents on gall-bladder motility remain undefined. AIM: To determine the effects of alpha- and beta-antagonists on gall-bladder motility in healthy humans. METHODS: In this single, blind, three-way crossover study, a slow-release formulation of propranolol 80 mg (beta-antagonist), indoramin 25 mg (post-synaptic alpha1-antagonist) and placebo were administered to 10 healthy volunteers on three separate days 8 h before the assessment of gall-bladder volumes by ultrasonography. Gall-bladder volumes were assessed in the fasting state and at 5-min intervals for 50 min after a standard proprietary enteral feed (Ensure 186 mL, Abbott). RESULTS: The fasting gall-bladder volumes of subjects who received placebo or indoramin were significantly different (mean +/- S.E.M.: 16.50 +/- 2.78 mL and 13.47 +/- 2.24 mL, respectively; P < 0.001, two-way analysis of variance). The fasting gall-bladder volume after the administration of propranolol was 17.49 +/- 2.37 mL and was not significantly different from placebo (16.50 +/- 2.78 mL). When the mean post-prandial gall-bladder volumes were compared, indoramin significantly enhanced post-prandial gall-bladder emptying compared to placebo (P < 0.001). There was no significant post-prandial volume difference between placebo and propranolol. CONCLUSIONS: Indoramin, an alpha-adrenergic antagonist, acts as a prokinetic agent, enhancing post-prandial gall-bladder emptying in healthy individuals.


Subject(s)
Adrenergic alpha-Antagonists/pharmacology , Gallbladder Emptying/drug effects , Indoramin/pharmacology , Adrenergic beta-Antagonists/pharmacology , Adult , Cross-Over Studies , Fasting/physiology , Female , Humans , Male , Postprandial Period/physiology , Propranolol/pharmacology , Single-Blind Method
19.
Dig Dis Sci ; 47(8): 1786-92, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12184531

ABSTRACT

The aims of this study were to characterize the endothelin (ET) system in human gallbladder by determining (1) the tissue content of ET-1 and ET-2 by ELISA; (2) the expression of mRNA of the ET precursors preproendothelin-1, -2, and -3; and (3) mRNA expression for the ETA and ETB receptors. Median content of ET-1/2 was significantly reduced in severely inflamed gallbladders compared to gallbladders with mild inflammation. There was an inverse correlation between content of ET-1/2 and inflammation score. mRNA for preproendothelin-2 was highly expressed in all samples, whereas mRNA for preproendothelin-1 was present in negligible quantities and mRNA for preproendothelin-3 was undetectable. mRNA for ETA receptors was expressed in all samples analyzed, whereas mRNA for ETB receptors was expressed at a much lower level. This study demonstrates the presence of ET-1/2 in human gallbladder. ET-1/2 content is decreased with increasing degrees of histological inflammation. ET-2 is likely to be the physiologically significant endothelin isopeptide expressed and ETA receptors appear to predominate in the human gallbladder.


Subject(s)
Cholecystitis/metabolism , Endothelin-1/analysis , Endothelin-2/analysis , Gallbladder/chemistry , Receptors, Endothelin/analysis , Endothelin-1/genetics , Endothelin-2/genetics , Endothelins/genetics , Enzyme-Linked Immunosorbent Assay , Humans , Polymerase Chain Reaction , Protein Precursors/genetics , RNA, Messenger/analysis , Receptor, Endothelin A , Receptor, Endothelin B , Receptors, Endothelin/genetics
20.
Recent Prog Horm Res ; 57: 149-79, 2002.
Article in English | MEDLINE | ID: mdl-12017541

ABSTRACT

A detailed understanding of the hormonal regulation of spermatogenesis is required for the informed assessment and management of male fertility and, conversely, for the development of safe and reversible male hormonal contraception. An approach to the study of these issues is outlined based on the use of well-defined in vivo models of gonadotropin/androgen deprivation and replacement, the quantitative assessment of germ cell number using stereological techniques, and the directed study of specific steps in spermatogenesis shown to be hormone dependent. Drawing together data from rat, monkey, and human models, we identify differences between species and formulate an overview of the hormonal regulation of spermatogenesis. There is good evidence for both separate and synergistic roles for both testosterone and follicle-stimulating hormone (FSH) in achieving quantitatively normal spermatogenesis. Based on relatively selective withdrawal and replacement studies, FSH has key roles in the progression of type A to B spermatogonia and, in synergy with testosterone, in regulating germ cell viability. Testosterone is an absolute requirement for spermatogenesis. In rats, it has been shown to promote the adhesion of round spermatids to Sertoli cells, without which they are sloughed from the epithelium and spermatid elongation fails. The release of mature elongated spermatids from the testis (spermiation) is also under FSH/testosterone control in rats. Data from monkeys and men treated with steroidal contraceptives indicate that impairment of spermiation is a key to achieving azoospermia. The contribution of 5alpha-reduced androgens in the testis to the regulation of spermatogenesis is also relevant, as 5alpha-reduced androgens are maintained during gonadotropin suppression and may act to maintain low levels of germ cell development. These concepts are also discussed in the context of male hormonal contraceptive development.


Subject(s)
Homeostasis , Hormones/physiology , Spermatogenesis , Androgens/physiology , Animals , Follicle Stimulating Hormone/pharmacology , Follicle Stimulating Hormone/physiology , Gonadotropin-Releasing Hormone/physiology , Haplorhini , Hormones/pharmacology , Humans , Hypothalamus/physiology , Male , Pituitary Gland/physiology , Rats , Testis/physiology , Testosterone/pharmacology , Testosterone/physiology
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