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1.
bioRxiv ; 2023 Jul 18.
Article in English | MEDLINE | ID: mdl-37503183

ABSTRACT

Aberrant angiogenesis could contribute to cognitive impairment, representing a therapeutic target for preventing dementia. However, most angiogenesis studies focus on model organisms. To test the relevance of angiogenesis to human cognitive aging, we evaluated associations of circulating blood markers of angiogenesis with brain aging trajectories in two deeply phenotyped human cohorts (n=435, age 74 + 9) with longitudinal cognitive assessments, biospecimens, structural brain imaging, and clinical data. Machine learning and traditional statistics revealed sex dimorphic associations of plasma angiogenic growth factors with brain aging outcomes. Specifically, angiogenesis is associated with higher executive function and less brain atrophy in younger women (not men), a directionality of association that reverses around age 75. Higher levels of basic fibroblast growth factor, known for pleiotropic effects on multiple cell types, predicted favorable cognitive trajectories. This work demonstrates the relevance of angiogenesis to brain aging with important therapeutic implications for vascular cognitive impairment and dementia.

2.
J Neuroinflammation ; 20(1): 20, 2023 Jan 31.
Article in English | MEDLINE | ID: mdl-36721258

ABSTRACT

Chronic microglia activation post-stroke is associated with worse neurological and cognitive outcomes. However, measurement of microglia activation in vivo is currently limited. Plasma derived extracellular vesicles (EVs) are cell-specific indicators that may allow for non-invasive measurement of microglia phenotype. The aim of this study was to identify activation-state specific microglia EVs (MEVs) in vitro followed by validation in an experimental stroke model. Following pro-inflammatory activation, MEVs contain the microglia protein TMEM119 alongside increased expression of the Toll-like receptor 4 co-receptor CD14. Immunoprecipitation followed by fluorescent nanoparticle tracking analysis (ONI Nanoimager) was used to confirm the isolation of TMEM119+/CD14+ EVs from rat plasma. Electron microscopy confirmed that TMEM119 and CD14 localize to the MEV membrane. To model ischemia, plasma was collected from 3-month wildtype Fischer344 rats prior to, 7 and 28 days after endothelin-1 or saline injection into the dorsal right striatum. Fluorescently labelled MEVs were directly measured in the plasma using nanoflow cytometry (Apogee A60 Microplus). We report a significant increase in circulating TMEM119+/CD14+ EVs 28-days post-stroke in comparison to baseline levels and saline-injected rats, which correlated weakly with stroke volume. TMEM119+/MHC-II+ EVs were also increased post-stroke in comparison to baseline and saline-injected animals. This study is the first to describe an EV biomarker of activated microglia detected directly in plasma following stroke and represents a future tool for the measurement of microglia activity in vivo.


Subject(s)
Extracellular Vesicles , Microglia , Stroke , Animals , Rats , Biomarkers , Corpus Striatum , Phenotype
3.
Brain Behav Immun ; 88: 699-710, 2020 08.
Article in English | MEDLINE | ID: mdl-32387511

ABSTRACT

OBJECTIVE: Exercise is one of the most potent strategies available to support cognitive health with age, yet substantial variability exists. Sexual dimorphism is evident for brain and immune functioning, the latter being implicated as important pathway for exercise. We examined the moderating role of sex on the relationship between physical activity and systemic inflammatory and brain health outcomes in support of more personalized approaches to behavioral interventions. METHODS: Our discovery cohort included 45 typically aging women matched on age (±5y) and education (±2y) to 45 men (mean age = 72.5; Clinical Dementia Rating = 0) who completed self-reported current physical activity (Physical Activity Scale for Elderly), blood draw, neuropsychological evaluation, and brain MRI. An independent sample of 45 typically aging women and 36 men who completed the same measures comprised a replication cohort. Plasma was analyzed for 11 proinflammatory cytokine and chemokine markers via MesoScale Discovery. RESULTS: Discovery cohort: Reported physical activity did not differ between sexes (150 vs. 157, p = 0.72). There was a significant interaction between sex and physical activity on chemokine markers MDC, MIP-1b, MCP-4, and eotaxin-3 (ps < 0.03), with a similar trend for MCP-1 and INFγ (ps < 0.09). Men who reported greater activity demonstrated lower inflammatory markers, an effect attenuated-to-absent in women. An interaction between sex and physical activity was also observed for parahippocampal volumes (p = 0.02) and cognition (processing speed and visual memory; ps < 0.04). Again, the beneficial effect of physical activity on outcomes was present in men, but not women. Replication cohort analyses conferred a consistent effect of sex on the relationship between physical activity and immune markers; models examining neurobehavioral outcomes did not strongly replicate. Across cohorts, post-hoc models demonstrated an interaction between sex and activity-related inflammatory markers on total gray matter volume and visual memory. Men with higher inflammatory markers demonstrated poorer brain structure and function, whereas inflammatory markers did not strongly relate to neurobehavioral outcomes in women. CONCLUSIONS: Greater physical activity was associated with lower markers of inflammation in clinically normal older men, but not women - an effect consistently replicated across cohorts. Additionally, men appeared disproportionately vulnerable to the adverse effects of peripheral inflammatory markers on brain structure and function compared to women. Immune activation may be a male-specific pathway through which exercise confers neurobehavioral benefit.


Subject(s)
Cognitive Aging , Exercise , Sex Characteristics , Aged , Aging , Brain/diagnostic imaging , Female , Humans , Male
4.
Alzheimers Dement ; 16(1): 91-105, 2020 01.
Article in English | MEDLINE | ID: mdl-31914227

ABSTRACT

INTRODUCTION: Leisure activities impact brain aging and may be prevention targets. We characterized how physical and cognitive activities relate to brain health for the first time in autosomal dominant frontotemporal lobar degeneration (FTLD). METHODS: A total of 105 mutation carriers (C9orf72/MAPT/GRN) and 69 non-carriers reported current physical and cognitive activities at baseline, and completed longitudinal neurobehavioral assessments and brain magnetic resonance imaging (MRI) scans. RESULTS: Greater physical and cognitive activities were each associated with an estimated >55% slower clinical decline per year among dominant gene carriers. There was also an interaction between leisure activities and frontotemporal atrophy on cognition in mutation carriers. High-activity carriers with frontotemporal atrophy (-1 standard deviation/year) demonstrated >two-fold better cognitive performances per year compared to their less active peers with comparable atrophy rates. DISCUSSION: Active lifestyles were associated with less functional decline and moderated brain-to-behavior relationships longitudinally. More active carriers "outperformed" brain volume, commensurate with a cognitive reserve hypothesis. Lifestyle may confer clinical resilience, even in autosomal dominant FTLD.


Subject(s)
Cognition/physiology , Exercise , Frontotemporal Lobar Degeneration , Leisure Activities , Neuropsychological Tests/statistics & numerical data , Aged , Atrophy/pathology , Female , Frontotemporal Lobar Degeneration/genetics , Frontotemporal Lobar Degeneration/pathology , Humans , Longitudinal Studies , Magnetic Resonance Imaging , Male , Middle Aged
5.
Cytokine ; 111: 481-489, 2018 11.
Article in English | MEDLINE | ID: mdl-29908923

ABSTRACT

BACKGROUND: Quantification of biofluid cytokines is a rapidly growing area of translational research. However, comparability across the expanding number of available assay platforms for detection of the same proteins remains to be determined. We aimed to directly compare a panel of commonly measured cytokines in plasma of typically aging adults across two high sensitivity quantification platforms, Meso Scale Discovery high performance electrochemiluminiscence (HPE) and single-molecule immunosorbent assays (Simoa) by Quanterix. METHODS: 57 community-dwelling older adults completed a blood draw, neuropsychological assessment, and brain MRI as part of a healthy brain aging study. Plasma samples from the same draw dates were analyzed for IL-10, IP-10, IL-6, TNFα, and IL-1ß on HPE and Simoa, separately. Reliable detectability (coefficient of variance (CV) < 20% and outliers 3 interquartiles above the median removed), intra-assay precision, absolute concentrations, reproducibility across platforms, and concurrent associations with external variables of interest (e.g., demographics, peripheral markers of vascular health, and brain health) were examined. RESULTS: The proportion of cytokines reliably measured on HPE (87.7-93.0%) and Simoa (75.4-93.0%) did not differ (ps > 0.32), with the exception of IL-1ß which was only reliably measured using Simoa (68.4%). On average, CVs were acceptable at <8% across both platforms. Absolute measured concentrations were higher using Simoa for IL-10, IL-6, and TNFα (ps < 0.05). HPE and Simoa shared only small-to-moderate proportions of variance with one another on the same cytokine proteins (range: r = 0.26 for IL-10 to r = 0.64 for IL-6), though platform agreement did not dependent on cytokine concentrations. Cytokine ratios within each platform demonstrated similar relative patterns of up- and down-regulation across HPE and Simoa, though still significantly differed (ps < 0.001). Supporting concurrent validity, all 95% confidence intervals of the correlations between cytokines and external variables overlapped between the two platforms. Moreover, most associations were in expected directions and consistently so across platforms (e.g., IL-6 and TNFα), though with several notable exceptions for IP-10 and IL-10. CONCLUSIONS: HPE and Simoa showed comparable detectability and intra-assay precision measuring a panel of commonly examined cytokine proteins, with the exception of IL-1ß which was not reliably detected on HPE. However, Simoa demonstrated overall higher concentrations and the two platforms did not show agreement when directly compared against one another. Relative cytokine ratios and associations demonstrated similar patterns across platforms. Absolute cytokine concentrations may not be directly comparable across platforms, may be analyte dependent, and interpretation may be best limited to discussion of relative associations.


Subject(s)
Biomarkers/blood , Biomarkers/metabolism , Cytokines/blood , Cytokines/metabolism , Aged , Aged, 80 and over , Female , Humans , Immunoassay/methods , Interleukin-10/blood , Interleukin-10/metabolism , Interleukin-1beta/blood , Interleukin-1beta/metabolism , Interleukin-6/blood , Interleukin-6/metabolism , Male , Middle Aged , Reproducibility of Results , Tumor Necrosis Factor-alpha/blood , Tumor Necrosis Factor-alpha/metabolism
6.
Reprod Domest Anim ; 52(5): 741-748, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28397300

ABSTRACT

This study investigated the effects of early induction of autophagy on embryonic development in pigs. For this, oocytes or embryos were treated with an autophagy inducer, rapamycin (RP), during post-activation (Pa), in vitro fertilization (IVF) and/or in vitro culture (IVC). When parthenogenesis (PA) embryos were untreated (control) or treated with various concentrations of RP for 4 hr during Pa, 100 nm RP showed a higher blastocyst formation (48.8 ± 2.7%) than the control (34.6 ± 3.0%). When PA embryos were treated during the first 24 hr of IVC, blastocyst formation was increased (p < .05) by 1 and 10 nm RP (61.9 ± 3.0 and 59.6 ± 3.0%, respectively) compared to the control (43.2 ± 1.8%) and 100 nm RP (47.8 ± 3.2%), with a higher embryo cleavage in response to 10 nm RP (87.3 ± 2.4%) than the control (74.1 ± 3.2%). RP treatment during IVC and Pa + IVC showed increased blastocyst formation (44.7 ± 2.5 and 44.1 ± 2.0%, respectively) compared to the control (33.2 ± 2.0%). In addition, RP treatment during Pa and/or IVC increased glutathione content and inversely reduced reactive oxygen species. In IVF, RP treatment for 6 hr during IVF significantly increased embryonic development (34.0 ± 2.6%) compared to the control (24.8 ± 1.6%), but treatment during IVC for 24 hr with RP did not (23.0 ± 3.8%). Autophagy was significantly increased in PA oocytes by the RP treatment during Pa but not altered by the treatment during the first 24 hr of IVC. Overall, RP treatment positively regulated the pre-implantation development of pig embryos, probably by regulating cellular redox state and stimulating autophagy.


Subject(s)
Embryonic Development/drug effects , Fertilization in Vitro/drug effects , Parthenogenesis/drug effects , Sirolimus/pharmacology , Animals , Autophagy/drug effects , Blastocyst/drug effects , Glutathione/analysis , Reactive Oxygen Species/analysis , Swine
7.
J Anim Sci ; 94(8): 3255-3263, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27695771

ABSTRACT

The purpose of this study was to examine the effects of alpha-linolenic acid (ALA) treatment during in vitro maturation (IVM) on nuclear maturation, intraoocyte glutathione (GSH) content, meiotic progression, and developmental competence after parthenogenesis (PA) and somatic cell nuclear transfer (SCNT) in pigs. Medium-199 containing 10% (vol/vol) porcine follicular fluid (PFF; PPF control) or 0.4% (wt/vol) fatty acid-free BSA (BSA control) was used for IVM. The proportion of oocytes reaching the metaphase II (MII) stage was not influenced by ALA treatment at various concentrations (50, 100, and 200 µ). However, treatment with 100 µ ALA significantly increased ( < 0.05) intraoocyte GSH content (1.19 vs. 1.00 and 0.92 pixels per oocyte, comparing the treated oocytes, BSA control, and PFF control, respectively) and embryonic development to the blastocyst stage after PA (47.1 vs. 35.5 and 35.2%) and SCNT (31.4 vs. 23.9 and 24.3%). ALA treatment (100 µ) accelerated oocyte maturation, and a higher proportion of ALA-treated oocytes (89.6%) reached the MII stage than did the untreated controls (75.5%) at 33 h of IVM. Mitogen-activated protein kinase kinase inhibitor (U0126) treatment during IVM inhibited nuclear maturation and embryonic development after PA. However, 100 µ ALA completely counteracted the suppressive effect of U0126 on nuclear maturation and partially counteracted the effect on blastocyst formation. Our results demonstrate that treatment with 100 µ ALA during IVM improves developmental competence by accelerating nuclear maturation and also influencing cytoplasmic maturation, such as increased GSH content in IVM oocytes.


Subject(s)
Embryonic Development/drug effects , Glutathione/drug effects , Mitogen-Activated Protein Kinases/drug effects , Swine/embryology , alpha-Linolenic Acid/pharmacology , Animals , Blastocyst , Butadienes/pharmacology , Female , Glutathione/metabolism , In Vitro Oocyte Maturation Techniques , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinases/metabolism , Nitriles/pharmacology , Nuclear Transfer Techniques , Oocytes/drug effects , Oocytes/physiology , Parthenogenesis , Phosphorylation , Swine/physiology
8.
Reprod Domest Anim ; 51(2): 220-6, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26834044

ABSTRACT

Cilostazol (CLZ) is a cyclic adenosine monophosphate (cAMP) modulator that influences the steady state of the meiotic stage. This study was conducted to determine the effects of CLZ treatment during in vitro maturation (IVM) on developmental competence of pig oocytes. Immature oocytes were exposed to 0 (control), 0.5, 2 and 4 µm CLZ during the first 22 h of IVM. Nuclear maturation, intraoocyte glutathione content and embryo cleavage after parthenogenesis (PA) and somatic cell nuclear transfer (SCNT) were not influenced by CLZ at any concentrations. However, 4 µm CLZ significantly (p < 0.05) improved blastocyst formation after PA (52.1% vs 38.7-46.0%) and SCNT relative to other concentrations (40.8% vs 25.0-30.7%). The mean cell numbers of SCNT blastocysts were significantly increased by 4 µm CLZ compared to the control (42.6 cells vs 35.3 cells/blastocyst). CLZ treatment significantly increased the intraoocyte cAMP level and effectively arrested oocytes at the germinal vesicle (GV) and GV break down stages compared to the control (74.5% vs 45.4%). Our results demonstrated that improved developmental competence of PA and SCNT pig embryos occurred via better synchronization of nuclear and cytoplasmic maturation induced by increased cAMP and delayed meiotic resumption after CLZ treatment.


Subject(s)
Cyclic AMP/metabolism , Meiosis/drug effects , Oocytes/drug effects , Swine , Tetrazoles/pharmacology , Animals , Cilostazol , Embryo Culture Techniques/veterinary , Meiosis/physiology , Oocytes/physiology , Phosphodiesterase 3 Inhibitors/pharmacology , Swine/embryology
9.
Neurol Sci ; 32(4): 559-69, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21630036

ABSTRACT

Often viewed as a potential tool for preclinical diagnosis in early asymptomatic stages of Alzheimer's disease (AD), the term "endophenotype" has acquired a recent popularity in the field. In this review, we analyze the construct of endophenotype-originally designed to discover genes, and examine the literature on potential endophenotypes for the late-onset form of AD (LOAD). We focus on the [18F]-fluoro-2-deoxyglucose (FDG) PET technique, which shows a characteristic pattern of hypometabolism in AD-related regions in asymptomatic carriers of the ApoE E4 allele and in children of AD mothers. We discuss the pathophysiological significance and the positive predictive accuracy of an FDG-endophenotype for LOAD in asymptomatic subjects, and discuss several applications of this endophenotype in the identification of both promoting and protective factors. Finally, we suggest that the term "endophenotype" should be reserved to the study of risk factors, and not to the preclinical diagnosis of LOAD.


Subject(s)
Alzheimer Disease/diagnostic imaging , Fluorodeoxyglucose F18 , Radiopharmaceuticals , Alzheimer Disease/genetics , Alzheimer Disease/physiopathology , Causality , Endophenotypes , Genetic Markers , Humans , Neuroprotective Agents/pharmacology , Positron-Emission Tomography
10.
Surgeon ; 4(4): 221-5, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16892839

ABSTRACT

Laryngopharyngeal reflux (LPR) is a common condition encountered in otolaryngological practice in the United Kingdom. It is one of the most important aetiological factors for many inflammatory disorders of the upper aerodigestive tract. The presentations are diverse and include chronic hoarseness, sensation of a foreign body in the throat, sore throat, dysphagia, postnasal drip, excessive throat mucous, chronic cough and throat clearing. LPR patients may not complain of heartburn. Although LPR is common, its diagnosis may not be easy, as its symptoms are non specific and the laryngeal findings are not always associated with symptom severity. This article discusses an overall view of LPR in terms of pathophysiology, clinical presentation, diagnosis and treatment


Subject(s)
Gastroesophageal Reflux/diagnosis , Laryngeal Diseases/diagnosis , Pharyngeal Diseases/diagnosis , Diagnosis, Differential , Gastroesophageal Reflux/etiology , Gastroesophageal Reflux/therapy , Humans , Laryngeal Diseases/etiology , Laryngeal Diseases/therapy , Pharyngeal Diseases/etiology , Pharyngeal Diseases/therapy
11.
Surgeon ; 4(1): 45-52, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16459500

ABSTRACT

Wegener's granulomatosis (WG) is an autoimmune disease which has a clinical predilection for the upper airways, lungs and kidneys. It is a necrotising granulomatous vasculitis which is associated with a distinct autoantibody--the antineutrophil cytoplasmic antibody (ANCA). A heightened index of suspicion by clinicians is needed in the diagnosis of this complex and rare condition. A multidisciplinary approach should then be used to treat this chronic multisystem disease. Treatment involves the use of various regimens of corticosteroids and immunosuppressive medication. Mortality due to WG has been significantly decreased by this therapy. In this article, we focus on clinical manifestations and review the salient histologic, laboratory and serologic features and treatment.


Subject(s)
Antibodies, Antineutrophil Cytoplasmic/immunology , Granulomatosis with Polyangiitis/immunology , Granulomatosis with Polyangiitis/pathology , Biopsy, Needle , Chronic Disease , Disease Progression , Female , Granulomatosis with Polyangiitis/epidemiology , Humans , Immunohistochemistry , Male , Prognosis , Risk Assessment , Survival Analysis
12.
Acta Oncol ; 39(1): 47-52, 2000.
Article in English | MEDLINE | ID: mdl-10752653

ABSTRACT

Despite standard-dose adjuvant chemotherapy, the prognosis for patients with breast cancer and extensive axillary lymph node involvement at diagnosis is poor. The efficacy of a paclitaxel-containing, high-dose chemotherapy protocol in 21 high-risk breast cancer patients is assessed. After standard-dose chemotherapy followed by peripheral blood stem cell (PBSC) mobilization, high-dose therapy with paclitaxel, carboplatin, and cyclophosphamide and CD34-selected PBSC rescue was given. Hematologic reconstitution after high-dose therapy was rapid. Main toxicity included diarrhea grade I or II in about half of the patients and infections were observed in 19%. Five-year probabilities for relapse and failure-free survival were 32% and 62%, respectively. High-dose consolidation with paclitaxel, carboplatin, and cyclophosphamide achieves a high failure-free survival in patients with high-risk breast cancer with acceptable toxicities and stable, long-term hematopoietic reconstitution. Evaluation of the benefit of high-dose therapy in these patients in larger prospective, randomized trials is warranted and currently under way.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Hematopoietic Stem Cell Transplantation , Paclitaxel/administration & dosage , Adult , Breast Neoplasms/pathology , Carboplatin/administration & dosage , Cyclophosphamide/administration & dosage , Disease-Free Survival , Dose-Response Relationship, Drug , Female , Humans , Middle Aged , Prognosis , Risk Factors , Treatment Outcome
13.
Br J Haematol ; 107(1): 204-6, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10520042

ABSTRACT

Knowledge of the spectrum of symptoms in patients with inherited afibrinogenaemia is limited by the rarity of this coagulation defect. We compared a large series of 55 afibrinogenaemic patients from Iran with 100 patients with severe factor VIII deficiency. In afibrinogenaemia there was a higher frequency of mucosal-type bleeding symptoms but joint and muscle bleeding was less frequent and severe than in haemophilia. Umbilical cord bleeding was relatively frequent only in afibrinogenaemic patients. Two young patients developed spontaneous thrombotic episodes and three women had recurrent abortions. Overall, in afibrinogenaemia bleeding symptoms are qualitatively different and less severe than in haemophilia. Afibrinogenaemia can also be accompanied by thrombotic manifestations.


Subject(s)
Afibrinogenemia/genetics , Hemorrhagic Disorders/genetics , Thrombosis/genetics , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Male , Middle Aged
14.
J Otolaryngol ; 27(6): 348-53, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9857321

ABSTRACT

OBJECTIVE: The present study was designed to generate population-based data on the prevalence and causes of hearing loss in rural Pakistani children. A community screening programme was utilized to identify and evaluate the hearing impaired. METHODS: The study was performed in conjunction with the Ministry of Population Welfare in Sialkot District, Punjab Province. School-aged children between the ages of 5 and 15 years were screened and examined for hearing impairment according to World Health Organization (WHO) protocols. Case-control analysis of audiometric, physical examination, and risk factors for hearing loss were performed, followed by chi-square analyses. RESULTS: A total of 607 children comprised the study population, with an overall point prevalence of hearing impairment of 7.9%. Fifty percent of all hearing loss was conductive in nature, amenable to either medical or surgical therapy. The risk factors most associated with conductive hearing loss were otorrhea and multiple ear infections greater than 5. In cases of severe hearing loss, 70% were the result of consanguinous marriages. Almost no cases of hearing loss were attributable to measles, mumps, rubella, and the TORCH infections. CONCLUSION: This study has generated some badly needed population-based data on the magnitude of the problem of hearing loss in rural Pakistan. It is hoped that the results of this work will stress the importance of hearing health in Pakistan and to encourage other professionals to pursue similar projects.


Subject(s)
Hearing Disorders/epidemiology , Rural Health/statistics & numerical data , Adolescent , Audiometry , Bacterial Infections/epidemiology , Case-Control Studies , Chi-Square Distribution , Child , Child, Preschool , Consanguinity , Female , Hearing Disorders/genetics , Hearing Loss, Conductive/drug therapy , Hearing Loss, Conductive/epidemiology , Hearing Loss, Conductive/surgery , Humans , Male , Mass Screening , Measles/epidemiology , Mumps/epidemiology , Otitis Media/epidemiology , Pakistan/epidemiology , Physical Examination , Population Surveillance , Prevalence , Risk Factors , Rubella/epidemiology , World Health Organization
15.
16.
Ann Saudi Med ; 16(4): 392-4, 1996 Jul.
Article in English | MEDLINE | ID: mdl-17372467

ABSTRACT

This is a retrospective study of 606 patients who underwent laparoscopic cholecystectomy at King Fahad Hospital, Medina, Saudi Arabia. The majority of them, 488 (80.5%), were females. Fifty (8.3%) patients presented with acute cholecystitis and 556 (91.7%) were chronic cases. Common bile duct stones were detected in 22 (3.6%) patients. Laparoscopic cholecystectomy was successful in 539 (89%) patients and converted to open cholecystectomy in 67 (11%) patients due to a variety of reasons. The mean operative time was 65.9 minutes. Most of the patients (64.7%) were discharged within 72 hours. There were no deaths in this series. The overall complication rate was 5.6% and the incidence of major ductal injury was 0.8%.

17.
J Endocrinol Invest ; 18(4): 265-70, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7560807

ABSTRACT

It is well established that dopamine (DA) plays an important role in inhibiting anterior pituitary function. DA receptors present in the pituitary show the pharmacological and biochemical characteristics of the D2 receptor; in fact, they are coupled to the inhibition of both adenylyl cyclase (AC) activity and the reduction of cytosolic free Ca2+ levels ([Ca2+]i) suggesting the involvement of different G-proteins. While the DA receptors present in human PRL-omas display these characteristics, no information is available on the coupling mechanism(s) of DA receptors expressed in nonfunctioning pituitary adenomas (NF-PA). In the present study, the effect of DA on AC activity and [Ca2+]i was investigated in 8 NFPAs surgically removed by the transphenoidal route. DA, at concentrations between 0.01 and 10 mumol/l, had no effect on cAMP formation in any tumor (from 27.6 +/- 11.9 to 27.9 +/- 11.0 pmol/mg prot/min; NS). By contrast, DA was effective in reducing [Ca2+]i levels either in resting conditions or after TRH stimulation in 5 out of 8 tumors, suggesting that NFPA express DA receptors with a defective transduction mechanism. As in these tumors SRIH caused the expected inhibition of both AC activity (from 31.4 +/- 9.3 to 24.4 +/- 11.0 pmol/mg prot/min; p < 0.005) and [Ca2+]i levels, it is likely that the lack of DA action on AC activity may be due to functional/structural properties of DA receptors expressed in NFPA, instead of a defect at the level of Gi proteins. In conclusion, these data indicate that DA receptors expressed in NFPA show a defective transduction mechanism, leading to a partial inhibitory response.


Subject(s)
Adenoma/metabolism , Adenylyl Cyclases/metabolism , Dopamine/pharmacology , Pituitary Neoplasms/metabolism , Signal Transduction , Adenoma/enzymology , Calcium/metabolism , Humans , In Vitro Techniques , Pituitary Neoplasms/enzymology
18.
J Clin Endocrinol Metab ; 78(2): 411-7, 1994 Feb.
Article in English | MEDLINE | ID: mdl-7906281

ABSTRACT

This article reports the effect of dopamine (DA) on adenylyl cyclase (AC) activity and intracellular free calcium concentration ([Ca2+]i) in 20 GH-secreting pituitary adenomas exclusively composed of somatotrophs (GH-omas) and 3 tumors largely constituted by mammosomatotrophs (MS-omas). DA (between 10 nmol/L and 100 mumol/L) did not reduce AC activity in any GH-omas, whereas the amine caused a significant inhibition in membranes from all MS-omas. The effect was detectable at DA concentrations higher than 0.1 mumol/L, and maximal inhibition (ranging from 24-30%) was reached at 10 mumol/L. The ergot derivative CH 29717 and l-sulpiride demonstrated potent agonist and antagonist activities, respectively. Somatostatin reduced AC activity in all tumors; the percent inhibition values (between 17-34%) were similar in GH-omas and MS-omas. In both GH-omas and MS-omas, DA (1 mumol/L) caused a significant [Ca2+]i reduction (between 17-44%) that was essentially due to the block of Ca2+ influx from the extracellular spaces. The receptors involved in this effect showed the pharmacological properties of D2 receptors. In conclusion, the DA effect in tumoral somatotrophs is defective; DA fails to exert an inhibitory action on AC activity. In mammosomatotrophs, the typical D2 receptor-effector coupling is retained, resulting in decreased AC activity in these cells.


Subject(s)
Adenoma/metabolism , Adenoma/pathology , Dopamine/physiology , Growth Hormone/metabolism , Pituitary Neoplasms/metabolism , Pituitary Neoplasms/pathology , Signal Transduction/physiology , Adenoma/ultrastructure , Adenylyl Cyclases/analysis , Adenylyl Cyclases/metabolism , Adenylyl Cyclases/physiology , Calcium/analysis , Calcium/metabolism , Cytosol/chemistry , Cytosol/metabolism , Dose-Response Relationship, Drug , Female , Humans , Immunohistochemistry , Male , Pituitary Neoplasms/ultrastructure , Receptors, Dopamine/analysis , Receptors, Dopamine/metabolism , Somatostatin/pharmacology , Sulpiride/pharmacology
19.
J Pak Med Assoc ; 43(10): 217-20, 1993 Oct.
Article in English | MEDLINE | ID: mdl-8114255

ABSTRACT

The Diploma in Family Medicine (DFM) Examination is a new certification offered by the College of Physicians and Surgeons of Pakistan, and its Department of Medical Education designed a scientific examination. First, the Expert Advisory Committee for Family Medicine was formed, relevant training objectives were determined, a training programme to achieve the objectives was designed and a valid syllabus was chosen. Then the examination was designed, where the candidates must pass the objective theory papers before taking the clinical examination. The clinical examination consisted of an Objective Structured Clinical Examination (OSCE) and traditional case presentations. The candidates had to pass each of the components, and attain an overall aggregate of 60%. In the first six examinations, 752 candidates sat for the theory examinations, 332 (44.14%) were eligible for the clinical examination, and 170 (23%) passed. If 60% marks obtained in case presentations is taken as the gold standard which is the current CPSP policy and compared to OSCE marks, then 75% marks in OSCE had a sensitivity of 67% and a specificity of 79%.


Subject(s)
Certification , Education, Medical, Graduate , Educational Measurement , Family Practice , Program Development , Pakistan , Societies, Medical
20.
J Endocrinol Invest ; 16(2): 109-15, 1993 Feb.
Article in English | MEDLINE | ID: mdl-7681860

ABSTRACT

This study, carried out on 9 nonfunctioning pituitary adenomas, was undertaken in order to evaluate the ability of these tumors to synthesize and release gonadotropins and/or free alpha-subunit (alpha-SU) of glycoproteins. The morphological study included electron microscopy and immunofluorescence analysis while hormone release was evaluated by the reverse hemolytic plaque assay (RHPA) and measurements in culture media. By electron microscopy in all tumors (6 null cell adenomas and 3 oncocytomas), it was possible to identify rough endoplasmic reticulum, Golgi apparatus and secretory granules. By immunofluorescence, 5 of 6 tumors were immunoreactive for one or more gonadotropin subunits; in particular, 5 adenomas were positive for alpha-SU and LH-beta, and 3 for FSH-beta. By the RHPA, about 1% of cells obtained from one single tumor formed plaques for LH-beta and alpha-SU while the remaining tumors were negative. Similarly, the study of media concentrations of LH, FSH and alpha-SU in 2 h culture revealed very low amounts of released hormones. In these experimental conditions no modification was observed after the addition of stimulatory agents such as TRH, GnRH and VIP. The present study clearly indicates that although the large majority of nonfunctioning tumors are positive for gonadotropins their secretory capacity is very low in both basal and stimulated conditions.


Subject(s)
Adenoma/metabolism , Gonadotropins, Pituitary/biosynthesis , Pituitary Neoplasms/metabolism , Adenoma/ultrastructure , Cytoplasmic Granules/ultrastructure , Endoplasmic Reticulum/ultrastructure , Fluorescent Antibody Technique , Follicle Stimulating Hormone/biosynthesis , Follicle Stimulating Hormone/metabolism , Glycoprotein Hormones, alpha Subunit/biosynthesis , Glycoprotein Hormones, alpha Subunit/metabolism , Golgi Apparatus/ultrastructure , Gonadotropin-Releasing Hormone/pharmacology , Gonadotropins, Pituitary/metabolism , Growth Hormone/biosynthesis , Growth Hormone/metabolism , Hemolytic Plaque Technique , Humans , Luteinizing Hormone/biosynthesis , Luteinizing Hormone/metabolism , Microscopy, Electron , Pituitary Neoplasms/ultrastructure , Prolactin/biosynthesis , Prolactin/metabolism , Thyrotropin-Releasing Hormone/pharmacology , Tumor Cells, Cultured , Vasoactive Intestinal Peptide/pharmacology
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