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Value and limitations of postoperative duplex scans after endovenous thermal ablation. J Vasc Surg Venous Lymphat Disord 2024; 12:101672. [PMID: 37678668 DOI: 10.1016/j.jvsv.2023.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/25/2023] [Accepted: 06/29/2023] [Indexed: 09/09/2023]
Abstract
BACKGROUND Endovenous thermal ablation (EVTA) of the lower extremity veins has risen to become the main treatment modality for symptomatic venous reflux disease. One of the main reported side effects of EVTA is recanalization. As of today, there is no clear protocol as to when follow-up duplex ultrasound scans should be performed. However, the standard for postoperative duplex after truncal ablation is within 1 week of the procedure. Our aim is to try to find whether there is a particular time period when postoperative duplex ultrasound scans should be performed to allow us to best diagnose recanalization. METHODS We retrospectively analyzed 9799 procedures in 3237 patients with chronic venous insufficiency owing to great, small, and anterior accessory saphenous vein insufficiency from 2012 to 2018. We excluded 466 perforator veins. All 9799 procedures were performed using EVTA in patients who failed to respond to conservative management initially. Postoperative duplex ultrasound scans were performed within 1 week (3-7 days postoperatively). We defined a successful obliteration as lack of color flow on postoperative scan. We defined symptomatic recanalization as presence of reflux on duplex ultrasound examination in the targeted vessel at follow-up with symptom recurrence. Follow-ups were performed every 3 months in the first year and every 6 months thereafter. RESULTS Patient ages ranged from 15 to 99 years. The median patient age at the time of the procedures was 63 years (interquartile range [IQR], 51-73 years). The median overall follow-up was 25 months (IQR, 4-56 months). The Clinical, Etiology, Anatomy, and Pathophysiology (CEAP) class of all the procedures were: C1, 21; C2, 208; C3, 3585; C4, 4680; C5, 188; and C6, 1117. There were 145 redo procedures performed after symptomatic recanalization was diagnosed in patients. CEAP class of the redo patients were: C1, 0; C2, 2; C3, 49; C4, 70; C5, 5; and C6, 19. CONCLUSIONS Most patients underwent a redo procedure performed within the first year after the initial procedure. Conversely, there was great variability as to when redo procedures were performed. Because there is no defined pattern as to when these symptomatic occurrences arise, it may not be required to perform postoperative duplex ultrasound scans after EVTA routinely, but instead when a patient comes back with symptoms such as swelling.
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Rates of ruptured abdominal aortic aneurysm during the COVID-19 pandemic in Ireland: letter to the editor. Ir J Med Sci 2023; 192:1825. [PMID: 36385697 PMCID: PMC9668696 DOI: 10.1007/s11845-022-03229-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 11/12/2022] [Indexed: 11/18/2022]
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Success Rate and Factors Predictive of Redo Endothermal Ablation of Anterior Accessory Saphenous Veins. J Vasc Surg Venous Lymphat Disord 2023. [DOI: 10.1016/j.jvsv.2022.12.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Race/Ethnicity and Outcomes of Venous Ablation Procedures. J Vasc Surg Venous Lymphat Disord 2023. [DOI: 10.1016/j.jvsv.2022.12.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Disparities in Decompressive Cranial Surgery Utilization in Severe Traumatic Brain Injury Patients without a Primary Extra-Axial Hematoma: A U.S. Nationwide Study. World Neurosurg 2023; 169:e16-e28. [PMID: 36202343 DOI: 10.1016/j.wneu.2022.09.113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/24/2022] [Accepted: 09/26/2022] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Decompressive craniectomy is recommended to reduce mortality in severe traumatic brain injury (TBI). Disparities exist in TBI treatment outcomes; however, data on disparities pertaining to decompressive craniectomy utilization is lacking. We investigated these disparities, focusing on race, insurance, sex, and age. METHODS Hospitalizations (2004-2014) were retrospectively extracted from the Nationwide Inpatient Sample. The criteria included are as follows: age ≥18 years and indicators of severe TBI diagnosis. Poor outcomes were defined as discharge to institutional care and death. Multivariable logistic regression models were used to assess the effects of race, insurance, age, and sex, on craniectomy utilization and outcomes. RESULTS Of 349,164 hospitalized patients, 6.8% (n = 23,743) underwent craniectomy. White (odds ratio [OR] = 0.50, 95% confidence interval [CI] = 0.44-0.57; P < 0.001) and Black (OR = 0.45, 95% CI = 0.32-0.64; P = 0.003) Medicare beneficiaries were less likely to undergo craniectomy. Medicare (P < 0.0001) and Medicaid beneficiaries (P < 0.0001) of all race categories had poorer outcomes than privately insured White patients. Black (OR = 1.2, 95% CI = 1.08-2.34; P = 0.001) patients with private insurance and Black (OR = 1.39, 95% CI = 1.22-1.58; P < 0.0001) Medicaid beneficiaries had poorer outcomes than privately insured White patients (P < 0.0001). Older patients (OR = 0.74, 95%, CI = 0.71-0.76; P < 0.001) were less likely to undergo craniectomy and were more likely to have poorer outcomes. Females (OR = 0.82, 95% CI = 0.76-0.88; P < 0.001) were less likely to undergo craniectomy. CONCLUSIONS There are disparities in race, insurance status, sex, and age in craniectomy utilization and outcome. This data highlights the necessity to appropriately address these disparities, especially race and sex, and actively incorporate these factors in clinical trial design and enrollment.
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Venous Thromboembolism Risk and Outcomes Following Decompressive Craniectomy in Severe Traumatic Brain Injury: An Analysis of the Nationwide Inpatient Sample Database. World Neurosurg 2022; 161:e531-e545. [DOI: 10.1016/j.wneu.2022.02.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 02/13/2022] [Accepted: 02/14/2022] [Indexed: 11/30/2022]
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Tubular Microdiscectomy for Recurrent Disc Prolapse Following Two Rounds of Open Laminectomy and Discectomy: A Case Report and Literature Review. EGYPTIAN SPINE JOURNAL 2022. [DOI: 10.57055/2314-8969.1006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Abstract
Importance Chimeric antigen receptor (CAR) T-cell therapy for relapsed or refractory hematologic malignant neoplasm causes severe neurologic adverse events ranging from encephalopathy and aphasia to cerebral edema and death. The cause of neurotoxicity is incompletely understood, and its unpredictability is a reason for prolonged hospitalization after CAR T-cell infusion. Objective To identify clinical and laboratory parameters predictive of neurotoxicity and to develop a prognostic score associated with its risk. Design, Setting, and Participants This single-center diagnostic/prognostic accuracy study was conducted at Brigham and Women's Hospital/Dana Farber Cancer Institute from April 2015 to February 2020. A consecutive sample of all patients undergoing CAR T-cell therapy with axicabtagene ciloleucel for relapsed or refractory lymphoma were assessed for inclusion (n = 213). Patients who had previously received CAR T cells or who were treated for mantle cell lymphoma were excluded (n = 9). Patients were followed up for a minimum of 30 days from the date of CAR T-cell infusion. Main Outcomes and Measures The primary outcomes were measures of performance (accuracy, sensitivity, specificity, area under the curve) of a diagnostic tool to predict the occurrence of CAR-associated neurotoxicity, as graded by the Common Terminology Criteria for Adverse Events criteria. Results Two hundred four patients (127 men [62.2%]; mean [SD] age, 60.0 [12.1] years) were included in the analysis, of which 126 (61.8%) comprised a derivation cohort and 78 (38.2%), an internal validation cohort. Seventy-three patients (57.9%) in the derivation cohort and 45 patients (57.7%) in the validation cohort experienced neurotoxicity. Clinical and laboratory values obtained early in admission were used to develop a multivariable score that can predict the subsequent development of neurotoxicity; when tested on an internal validation cohort, this score had an area under the curve of 74%, an accuracy of 77%, a sensitivity of 82%, and a specificity of 70% (positive:negative likelihood ratio, 2.71:0.26). Conclusions and Relevance The score developed in this study may help predict which patients are likely to experience CAR T-cell-associated neurotoxicity. The score can be used for triaging and resource allocation and may allow a large proportion of patients to be discharged from the hospital early.
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Neurological toxicities associated with chimeric antigen receptor T-cell therapy. Brain 2019; 142:1334-1348. [DOI: 10.1093/brain/awz053] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/21/2018] [Accepted: 01/18/2019] [Indexed: 12/13/2022] Open
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Pattern of liver diseases in Sudanese children. SUDAN JOURNAL OF MEDICAL SCIENCES 2011. [DOI: 10.4314/sjms.v5i4.64498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Liver Biopsy: Is it Safe in Children? SUDAN JOURNAL OF MEDICAL SCIENCES 2010. [DOI: 10.4314/sjms.v5i3.62004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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First report on Leishmania major/HIV coinfection in a Sudanese patient. EASTERN MEDITERRANEAN HEALTH JOURNAL = LA REVUE DE SANTE DE LA MEDITERRANEE ORIENTALE = AL-MAJALLAH AL-SIHHIYAH LI-SHARQ AL-MUTAWASSIT 2010; 16:702-703. [PMID: 20799602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Asynchronous release of GABA via tonic cannabinoid receptor activation at identified interneuron synapses in rat CA1. Eur J Neurosci 2010; 31:1196-207. [PMID: 20345910 DOI: 10.1111/j.1460-9568.2010.07165.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The influence of local circuit interneurons is thought to play an important role in adjusting synaptic strength via endogenous cannabinoid type 1 (CB1) receptors. Using paired whole-cell recordings, combined with double immunofluorescence and biocytin labelling in acute slices of rat CA1 at postnatal day 18-23, we investigated the properties of Cholecystokinin (CCK)-positive stratum radiatum local circuit interneuron connections that utilised CB1 receptors. Three types of synaptic connections were studied, lacunosum-moleculare-radiatum perforant path-associated (LM-R PPA) to Shaffer collateral-associated (SCA) interneurons, SCA-SCA interneurons and SCA-pyramidal cells. These three synapses were differentially under tonic reduction of inhibition that was blocked by the CB1 receptor inverse agonist AM-251 (10 microM), which enhanced IPSPs. The strength of tonic reduction of inhibition was correlated with asynchronous release which was apparent at connections among interneurons. AM-251 increased the ratio of synchronous to asynchronous release (synchronicity ratio), while the CB receptor agonist anandamide (14 microM) decreased the synchronicity ratio. Fast and slow calcium chelators (BAPTA-AM and EGTA-AM) also increased the synchronicity ratio, accelerated inhibitory time courses and reduced IPSP amplitudes. These data suggest that CB1 receptors at connections among interneuron synapses play a role in tonic suppression of inhibition and govern the asynchronous release of GABA, modulating the time windows of inhibition. Effects of calcium chelators suggest that asynchronous release is a result of a long-lasting presynaptic calcium transients and/or a large distance between calcium source and sensor of exocytosis. These properties of specialised inhibitory neurons may have important modulatory roles in controlling spike timing among local circuit interneurons.
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Primary invasive micropapillary carcinoma of the colon: case report and review of the literature. Pathologica 2008; 100:428-430. [PMID: 19253607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Invasive micropapillary carcinoma is associated with frequent lymph node metastases and adverse clinical outcome. It has been reported in breast, urinary bladder, lung and the parotid gland, but very rarely in the colon. We report a new case in a 63-year-old man involving the colon, and discuss the clinicopathologic features of this rare and particularly aggressive tumour.
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Identification of novel BRCA large genomic rearrangements in Singapore Asian breast and ovarian patients with cancer. Clin Genet 2007; 71:331-42. [PMID: 17470134 DOI: 10.1111/j.1399-0004.2007.00773.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Large genomic rearrangements have been reported to account for about 10-15% of BRCA1 gene mutations. Approximately, 90 BRCA rearrangements have been described to date, all of which but one have been reported in Caucasian populations of predominantly Western European descent. Knowledge of BRCA genomic rearrangements in Asian populations is still largely unknown. In this study, we have investigated for the presence of BRCA rearrangements among Asian patients with early onset or familial history of breast or ovarian cancer. Using multiplex ligation-dependent probe amplification (MLPA), we have analyzed 100 Singapore patients who previously tested negative for deleterious BRCA mutations by the conventional polymerase chain reaction-based mutation detection methods. Three novel BRCA rearrangements were detected, two of which were characterized. The patients with the rearrangements, a BRCA1 exon 13 duplication, a BRCA1 exon 13-15 deletion and a BRCA2 exon 4-11 duplication, comprise 3% of those previously tested negative for BRCA mutations. Of the BRCA1 and BRCA2 pathogenic mutations identified in our studies on Asian high-risk breast and ovarian patients with cancer to date, these rearrangements constitute 2/19 and 1/2 of the BRCA1 and BRCA2 pathogenic mutations, respectively. Given the increasing number of rearrangements reported in recent years and their contribution to the BRCA mutation spectrum, the presence of BRCA large exon rearrangements in Asian populations should be investigated where clinical, diagnostic service is recommended.
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BRCA1 disease-associated haplotypes in Singapore Malay women with early-onset breast/ovarian cancer. Breast Cancer Res Treat 2007; 104:351-3. [PMID: 17406974 DOI: 10.1007/s10549-006-9467-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Accepted: 11/25/2006] [Indexed: 11/29/2022]
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Abstract
OBJECTIVE To determine current practice in the delivery of parenteral nutrition (PN) in Australian hospitals. DESIGN A cross-sectional mail survey. SETTING Acute-care adult hospitals with greater than 200 beds in Australia. SUBJECTS A total of 67 hospitals (65.7% response rate). INTERVENTION Surveys were posted to hospitals. A reminder letter with a second copy of the survey was posted 3 weeks later to non-respondents. RESULTS Twenty-seven (40.3%) of the hospitals have a PN team and 50 (74.6%) have a hospital protocol for PN delivery. An inaccessible or non-functional gastrointestinal tract is the most common indicator for commencing PN. Fat infusion is calculated by 24 (38.7%) respondents with a mean (s.d.) maximum amount of fat provided of 2.0 (0.7) g/kg/day. Over half (n=35) reported calculating carbohydrate infusion at a maximum amount of 5.4 (1.0) mg/kg/min. Two-thirds (n=41) reported commencing PN at a rate of 50% or less of goal rate. Blood glucose levels (BGL) were monitored at least once per day by the majority of respondents (n=56, 83.6%). Insulin infusion was commenced at varying BGL. Most respondents (n=40, 59.7%) reported ceasing PN when at least half of the patient's requirements are being met either orally or enterally. A number of practice guidelines were identified and the results of the survey were compared with these guidelines. CONCLUSIONS Where there are clear practice guidelines, current practice appears to be in line with these recommendations, however, where evidence is lacking, practice is varied.
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The founder mutation BRCA1c.2845insA identified in a fallopian tube cancer patient: a case report. Int J Gynecol Cancer 2006; 16 Suppl 1:362-5. [PMID: 16515624 DOI: 10.1111/j.1525-1438.2006.00221.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Fallopian tube carcinoma is a very rare tumor, comprising less than 1% of all gynecologic cancers and found primarily in postmenopausal women. With the disease being so uncommon, little is known about its causes and/or risk factors, and treatment approaches have been taken from experiences with ovarian cancer. We describe a case of a 42-year-old woman with fallopian tube cancer in which the founder mutation BRCA1c.2845insA was detected by mutational analysis. This same mutation was subsequently detected in four unaffected members of her family following genetic counseling. We report an association between this founder mutation and fallopian tube cancer as part of the hereditary breast cancer syndrome in an Asian population. A literature review of the association between this rare malignancy and BRCA mutation carriers and its implications to prophylactic surgery is discussed.
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BRCA1 c.2845insA is a recurring mutation with a founder effect in Singapore Malay women with early onset breast/ovarian cancer. J Med Genet 2003; 40:e117. [PMID: 14569140 PMCID: PMC1735289 DOI: 10.1136/jmg.40.10.e117] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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BRCA1 c.2845insA is a founder mutation in Singaporean Malay women with early onset breast/ovarian cancer. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2003; 32:S53-5. [PMID: 14968737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
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Abstract
Pseudomonas aeruginosa clinical isolate PA35 is resistant to amino- and ureido-penicillins, has intermediate susceptibility to cefsulodin, cefepime and aztreonam, and is susceptible to imipenem and ceftazidime. Cloning and sequencing revealed a new beta-lactamase variant, OXA-35, sharing 96% amino acid identity with OXA-10. OXA-35 displays a restricted-substrate hydrolysis profile with improved hydrolysis of amoxicillin and cloxacillin compared with OXA-10. OXA-35 differs from derivatives OXA-19 and OXA-28 by one amino acid substitution and may be a progenitor of these OXA-13-like extended-spectrum beta-lactamases.
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Kainate receptors regulate unitary IPSCs elicited in pyramidal cells by fast-spiking interneurons in the neocortex. J Neurosci 2001; 21:2992-9. [PMID: 11312283 PMCID: PMC6762560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
Unitary IPSCs elicited by fast-spiking (FS) interneurons in layer V pyramidal cells of the neocortex were studied by means of dual whole-cell recordings in acute slices. FS to pyramidal cell unitary IPSCs were depressed by (RS)-S-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl) (ATPA), a kainate (KA) receptor agonist, and by the endogenous agonist l-glutamate in the presence of AMPA, NMDA, mGluR, and GABA(B) receptor antagonists. This effect was accompanied by an increase in failure rate of synaptic transmission, in the coefficient of variation, and in the paired pulse ratio, indicating a presynaptic origin of the IPSC depression. Pairing the activation of the presynaptic neuron with a depolarization of the postsynaptic cell mimicked the decrease of unitary IPSCs, and this effect persisted when postsynaptic sodium action potentials were blocked with the local anesthetic QX314. The effects of ATPA, glutamate, and of the pairing protocol were almost totally blocked by CNQX. These data suggest that KA receptors located on presynaptic FS cell terminals decrease the release of GABA and can be activated by glutamate released from the somatodendritic compartment of the postsynaptic pyramidal cells.
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Abstract
BACKGROUND Haptoglobin knockout (Hp-/-) mice are more sensitive to phenylhydrazine-induced hemolysis than Hp+/+ mice. METHODS Hemolysis was induced in Hp-/- and Hp+/+ mice using phenylhydrazine. Relative renal tissue damage and function were then assessed. RESULTS Hp-/- mice had higher basal levels of renal lipid peroxidation, as evidenced by levels of malonaldehyde and 4-hydroxy-2(E)-nonenal (MDA/HNE). After the administration of phenylhydrazine, levels of 8-hydroxyguanine (but not other products of oxidative DNA damage) were significantly elevated in the renal DNA. There was also increased induction of heme oxygenase-1. The more severe renal damage in Hp-/- mice was also evident in the delayed erythropoietin gene expression and poorer renal clearance of 3H-inulin. This reduction in glomerular filtration function in Hp+/+ and Hp-/- mice could be restored to baseline by vasodilators (prazosin or diazoxide), implicating renal vasoconstriction as a major mechanism of acute renal failure during induced hemolysis. Precipitation of hemoglobin in the kidney was not increased in Hp-/- mice. CONCLUSIONS Haptoglobin appears to play an important physiological role as an antioxidant, particularly during hemolysis.
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Abstract
CA1 basket cells are identifiable by an axonal arbour largely confined to, and spanning, the entire depth of stratum pyramidale where they innervate pyramidal somata and proximal dendrites. Basket cells display a range of electrophysiological properties and the inhibitory postsynaptic potentials (IPSPs) they elicit in pyramidal cells vary widely in duration. To determine whether these parameters are correlated, we used paired intracellular recordings, with biocytin filling, in pyramidal cells of adult hippocampal slices, and studied gamma-aminobutyric acid (GABAA) IPSPs (n = 43) elicited by putative basket cells (n = 35) with axons largely confined to stratum pyramidale in simultaneously recorded pyramidal cells. Fast-spiking interneurons elicited relatively brief IPSPs, while IPSPs elicited by burst-firing cells were amongst the slowest. Regular spiking interneurons elicited fast and slow GABAA IPSPs, but any one interneuron elicited IPSPs with remarkably similar durations in two to four pyramidal targets. However, with different types of target for a single putative basket cell, IPSPs elicited in postsynaptic interneurons were briefer than in pyramidal cells. Vertical oriens cells with somata in stratum oriens and a narrow, sparse axonal arbour in stratum pyramidale in transverse hippocampal slices, elicited IPSPs whose rise times and half widths clustered around intermediate values. Durations of IPSPs in pyramidal cells thus correlate, to a degree, with the physiological properties of presynaptic basket cells. The seven-fold range of durations observed (10-70 ms half widths) may underlie contributions made by different basket cells to hippocampal rhythms of different frequencies.
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CA1 pyramidal to basket and bistratified cell EPSPs: dual intracellular recordings in rat hippocampal slices. J Physiol 1998; 507 ( Pt 1):201-17. [PMID: 9490840 PMCID: PMC2230771 DOI: 10.1111/j.1469-7793.1998.201bu.x] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
1. Dual intracellular recordings in the CA1 region of adult rat hippocampal slices and biocytin filling of synaptically connected cells were used to study the excitatory postsynaptic potentials (EPSPs) elicited in basket (n = 7) and bistratified interneurones (n = 7) by action potentials activated in simultaneously recorded pyramidal cells. 2. Interneurones could be subdivided according to their electrophysiological properties into classical fast spiking, burst firing, regular spiking and fast spiking cells with a rounded spike after-hyperpolarization. These physiological classes did not, however, correlate with morphological type. EPSPs were not recorded in regular spiking cells. 3. Average EPSP amplitudes were larger in bistratified cells (range, 0.5-9 mV) than in basket cells (range, 0. 15-3.6 mV) and the probability of obtaining a pyramidal cell-interneurone EPSP was also higher for the bistratified cells (1:7) than for the basket cells (1:22). EPSP 10-90 % rise times in bistratified cells (0.7-2 ms) and their widths at half-amplitude (3. 9-11.2 ms) were slightly longer than in basket cells (rise times, 0.4-1.6 ms; half-widths, 2.2-9.7 ms). 4. The majority of these EPSPs (6 of 8 tested) increased in amplitude and duration with postsynaptic depolarization, although in two (of 4) basket cells the voltage relation was conventional. 5. All EPSPs tested in both basket (n = 7) and bistratified cells (n = 5) decreased in amplitude with repetitive presynaptic firing. The average amplitudes of second EPSPs elicited within 15 ms of the first were between 34 and 94 % of the average amplitude of the first EPSP. Third and fourth EPSPs in brief trains were further depressed. This depression was associated with an increase in the incidence of apparent failures of transmission indicating a presynaptic locus.
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Facilitating pyramid to horizontal oriens-alveus interneurone inputs: dual intracellular recordings in slices of rat hippocampus. J Physiol 1998; 507 ( Pt 1):185-99. [PMID: 9490837 PMCID: PMC2230767 DOI: 10.1111/j.1469-7793.1998.185bu.x] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
1. In adult rat hippocampal slices, simultaneous intracellular recordings from pyramidal cells in CA1 and interneurones near the stratum oriens-alveus border revealed excitatory connections that displayed facilitation on repetitive activation in twelve of thirty-six pairs tested. 2. Postsynaptic interneurones were classified as horizontal oriens-alveus interneurones by the pronounced 'sag' in response to hyperpolarizing current injection, high levels of spontaneous synaptic activity and by the morphology of their somata and dendrites, which were confined to stratum oriens-alveus and their axons which projected to stratum lacunosum-moleculare where they ramified extensively, in the region of entorhinal cortex input to CA1. 3. Excitatory postsynaptic potentials (EPSPs) elicited by single pyramidal cells were 0 to 12 mV in amplitude. Mean EPSP amplitude (single spikes) was 0.93 +/- 1. 06 mV at -70 +/- 2.3 mV (n = 10). The rise time was 1.2 +/- 0.5 ms and the width at half-amplitude was 7.5 +/- 4.7 ms. 4. EPSPs fluctuated greatly in amplitude; the mean coefficient of variation was 0.84 +/- 0.37 for the first EPSP and 0.47 +/- 0.24 for the second. Apparent failures of transmission frequently occurred after first presynaptic spikes but less frequently after the second or subsequent spikes in brief trains. 5. EPSPs displayed facilitation at membrane potentials between -80 mV and spike threshold. Second EPSPs within 20 ms of the first were 253 +/- 48 % (range, 152-324 %) of the mean first EPSP amplitude. Third EPSPs within 60 ms were 266 +/- 70 % (range, 169-389 %) and fourth EPSPs within 60-120 ms were 288 +/- 71 % (range, 188-393 %). Both proportions of apparent failures of transmission and coefficient of variation analysis indicated a presynaptic locus for this facilitation.
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Thyroid function in patients with mycetoma. EAST AFRICAN MEDICAL JOURNAL 1995; 72:454-6. [PMID: 7498029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Thyroid function was assessed in seventy two patients with various types of mycetoma. There was no evidence of clinical or biochemical thyroid dysfunction in these patients. The symptoms encountered in some of the mycetoma patients mimic those of hypothyroidism should be attributed to other factors possibly mental depression and apathy.
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