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1.
Surg Obes Relat Dis ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38964945

RESUMO

BACKGROUND: The prevalence of super obesity (body mass index [BMI] > 50) continues to rise. However, the adoption of bariatric surgery in this population remains very low. There are limited studies evaluating the utility of endoscopic sleeve gastroplasty (ESG) in super obesity. OBJECTIVES: The purpose of this study is to evaluate the short-term safety profile of ESG in patients with super obesity using data from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database. SETTING: United States. METHODS: We retrospectively analyzed patients who underwent ESG and sleeve gastrectomy (SG) from 2016 to 2021. Patients with BMI >50 who underwent ESG were compared to ESG patients with BMI <50 and also SG patients with BMI >50. Primary outcomes included the incidence of severe adverse events (AEs), hospital readmission, reintervention, and reoperation within 30 days of the primary procedure. Secondary outcomes included procedure time, hospital length of stay, and total body weight loss at 30 days. RESULTS: There were no significant differences in AE, reoperations, hospital readmissions, or reinterventions for patients with super obesity undergoing ESG, compared to patients with BMI below 50. Mean total body weight loss was greater in patients with super obesity. There were no significant differences in AEs for patients with super obesity who underwent ESG versus SG, although ESG patients had more hospital readmissions, reinterventions, and reoperations. CONCLUSIONS: ESG may be performed safely, with comparable safety to SG, in patients with BMI as high as 70. However, further studies are needed to validate the feasibility and long-term efficacy prior to clinical implementation.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38898569

RESUMO

Backgrounds/Aims: The guidelines regarding the management of intraductal papillary mucinous neoplasms (IPMNs) all have slightly different surgical indications for high-risk lesions. We aim to retrospectively compare the accuracy of four guidelines in recommending surgery for high-risk IPMNs, and assess the accuracy of elevated CA-19-9 levels and imaging characteristics of IPMNs considered high-risk in predicting malignancy or high-grade dysplasia (HGD). Methods: The final histopathological diagnosis of surgically resected high-risk IPMNs during 2013-2020 were compared to preoperative surgical indications, as enumerated in four guidelines: the 2015 American Gastroenterological Association (AGA), 2017 International Consensus, 2018 European Study Group, and 2018 American College of Gastroenterology (ACG). Surgery was considered "justified" if histopathology of the surgical specimen showed HGD/malignancy, or there was postoperative symptomatic improvement. Results: Surgery was postoperatively justified in 26/65 (40.0%) cases. All IPMNs with HGD/malignancy were detected by the 2018 ACG and the combined (absolute and relative criteria) 2018 European guidelines. The combined ("high-risk stigmata" and "worrisome features") 2017 International guideline missed 1/19 (5.3%) IPMNs with HGD/malignancy. The 2015 AGA guideline missed the most cases (11/19, 57.9%) of IPMNs with HGD/malignancy. We found the features most-associated with HGD/malignancy were pancreatic ductal dilation, and elevated CA-19-9 levels. Conclusions: Following the 2015 AGA guideline results in the highest rate of missed HGD/malignancy, but the lowest rate of operating on IPMNs without these features; meanwhile, the 2018 ACG and the combined (absolute and relative criteria) 2018 European guidelines result in more operations for IPMNs without HGD/malignancy, but the lowest rates of missed HGD/malignancy in IPMNs.

3.
BMJ Open Gastroenterol ; 11(1)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38653505

RESUMO

BACKGROUND: There is limited data on the incidence of gastrointestinal-specific pathology in gender non-conforming (GNC) populations. METHODS: Retrospective analysis of pancreatitis incidence rates in transgender and GNC persons exposed and not exposed to gender-affirming hormone therapy (GAHT). RESULTS: 7 of the 1333 patients on hormone therapy had an incidence of pancreatitis. 0 of the 615 patients with no history of GAHT use developed pancreatitis. Representing a 6.96 (95% CI 2.76 to 848.78) for the development of pancreatitis in patients with exposure to GAHT therapy. CONCLUSION: Clinicians working with GNC individuals should be aware of this possible association.


Assuntos
Pancreatite , Pessoas Transgênero , Humanos , Pessoas Transgênero/estatística & dados numéricos , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Pancreatite/epidemiologia , Pancreatite/induzido quimicamente , Adulto , Incidência , Terapia de Reposição Hormonal/efeitos adversos , Terapia de Reposição Hormonal/estatística & dados numéricos , Terapia de Reposição Hormonal/métodos , Idoso
4.
Ann Hepatobiliary Pancreat Surg ; 28(2): 144-154, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38356257

RESUMO

Backgrounds/Aims: Socioeconomic determinants of health are incompletely characterized in cholangiocarcinoma (CCA). We assessed how socioeconomic status influences initial treatment decisions and survival outcomes in patients with CCA, additionally performing multiple sub-analyses based on anatomic location of the primary tumor. Methods: Observational study using the 2018 submission of the Surveillance, Epidemiology, and End Results (SEER)-18 Database. In total, 5,476 patients from 2004-2015 with a CCA were separated based on median household income (MHI) into low income (< 25th percentile of MHI) and high income (> 25th percentile of MHI) groups. Seventy-three percent of patients had complete follow up data, and were included in survival analyses. Survival and treatment outcomes were calculated using R-studio. Results: When all cases of CCA were included, the high-income group was more likely than the low-income to receive surgery, chemotherapy, and local tumor destruction modalities. Initial treatment modality based on income differed significantly between tumor locations. Patients of lower income had higher overall and cancer-specific mortality at 2 and 5 years. Non-cancer mortality was similar between the groups. Survival differences identified in the overall cohort were maintained in the intrahepatic CCA subgroup. No differences between income groups were noted in cancer-specific or overall mortality for perihilar tumors, with variable differences in the distal cohort. Conclusions: Lower income was associated with higher rates of cancer-specific mortality and lower rates of surgical resection in CCA. There were significant differences in treatment selection and outcomes between intrahepatic, perihilar, and distal tumors. Population-based strategies aimed at identifying possible etiologies for these disparities are paramount to improving patient outcomes.

6.
Clin Gastroenterol Hepatol ; 21(11): 2797-2806.e6, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36858145

RESUMO

BACKGROUND & AIMS: Socioeconomic determinants of health are understudied in early stage esophageal adenocarcinoma. We aimed to assess how socioeconomic status influences initial treatment decisions and survival outcomes in patients with T1a esophageal adenocarcinoma. METHODS: We performed an observational study using the 2018 submission of the Surveillance, Epidemiology, and End Results-18 database. A total of 1526 patients from 2004 to 2015 with a primary T1aN0M0 esophageal adenocarcinoma were subdivided into 3 socioeconomic tertiles based on their median household income. Endoscopic trends over time, rates of endoscopic and surgical treatment, 2- and 5-year overall survival, cancer-specific mortality, and non-cancer-specific mortality were calculated. Statistical analysis was performed using R-studio. RESULTS: Patients within the lowest median household income tertile ($20,000-$54,390) were associated with higher cancer-specific mortality at 2 years (P < .01) and 5 years (P < .02), and lower overall survival at 2 and 5 years (P < .01) compared with patients in higher income tertiles. Patients with a higher income had a decreased hazard ratio for cancer-specific mortality (hazard ratio, 0.66; 95% CI, 0.45-0.99) in a multivariate Cox proportional hazards regression model. Patients within the higher income tertile were more likely to receive endoscopic intervention (P < .001), which was associated with improved cancer-specific mortality compared with patients who received primary surgical intervention (P = .001). The South had lower rates of endoscopy compared with other regions. CONCLUSIONS: Lower median household income was associated with higher rates of cancer-specific mortality and lower rates of endoscopic resection in T1aN0M0 esophageal adenocarcinoma. Population-based strategies aimed at identifying and rectifying possible etiologies for these socioeconomic and geographic disparities are paramount to improving patient outcomes in early esophageal cancer.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Humanos , Disparidades Socioeconômicas em Saúde , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/cirurgia , Adenocarcinoma/epidemiologia , Adenocarcinoma/terapia , Endoscopia Gastrointestinal
7.
Gastrointest Endosc ; 97(1): 11-21.e4, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35870507

RESUMO

BACKGROUND AND AIMS: Endoscopic sleeve gastroplasty (ESG) is an incisionless, transoral, restrictive bariatric procedure designed to imitate sleeve gastrectomy (SG). Comparative studies and large-scale population-based data are limited. Additionally, no studies have examined the impact of race on outcomes after ESG. This study aims to compare short-term outcomes of ESG with SG and evaluate racial effects on short-term outcomes after ESG. METHODS: We retrospectively analyzed over 600,000 patients in the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database from 2016 to 2020. We compared occurrences of adverse events (AEs), readmissions, reoperations, and reinterventions within 30 days after procedures. Multivariate regression evaluated the impact of patient factors, including race, on AEs. RESULTS: A total of 6054 patients underwent ESG and 597,463 underwent SG. AEs were low after both procedures with no significant difference in major AEs (SG vs ESG: 1.1% vs 1.4%; P > .05). However, patients undergoing ESG had more readmissions (3.8% vs 2.6%), reoperations (1.4% vs .8%), and reinterventions (2.8% vs .7%) within 30 days (P < .05). Race was not significantly associated with AEs after ESG, with black race associated with a higher risk of AEs in SG. CONCLUSIONS: ESG demonstrates a comparable major AE rate with SG. Race did not impact short-term AEs after ESG. Further prospective studies long-term studies are needed to compare ESG with SG.


Assuntos
Cirurgia Bariátrica , Gastroplastia , Obesidade Mórbida , Humanos , Gastroplastia/efeitos adversos , Gastroplastia/métodos , Estudos Retrospectivos , Melhoria de Qualidade , Estudos Prospectivos , Redução de Peso , Obesidade/cirurgia , Resultado do Tratamento , Gastrectomia/métodos , Acreditação , Obesidade Mórbida/cirurgia
8.
Ther Adv Gastrointest Endosc ; 14: 26317745211045769, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34589706

RESUMO

The prevalence of pancreatic cysts has increased significantly over the last decade, partly secondary to increased quality and frequency of cross-sectional imaging. While the majority never progress to cancer, a small number will and need to be followed. The management of pancreatic cysts can be both confusing and intimidating due to the multiple guidelines with varying recommendations. Despite the differences in the specifics of the guidelines, they all agree on several high-risk features that should get the attention of any clinician when assessing a pancreatic cyst: presence of a mural nodule or solid component, dilation of the main pancreatic duct (or presence of main duct intraductal papillary mucinous neoplasm), pancreatic cyst size ⩾3-4 cm, or positive cytology on pancreatic cyst fluid aspiration. Other important criteria to consider include rapid cyst growth (⩾5 mm/year), elevated serum carbohydrate antigen 19-9 levels, new-onset diabetes mellitus, or acute pancreatitis thought to be related to the cystic lesion.

10.
Gastrointest Endosc Clin N Am ; 29(2): 351-367, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30846158

RESUMO

Most patients with perihilar cholangiocarcinoma present with surgically unresectable disease owing to the insidious nature of this malignancy. Relief of malignant perihilar biliary obstruction is a key aspect of cholangiocarcinoma. Although palliative stenting using uncovered metal stents has been advocated in patients with unresectable malignant perihilar biliary strictures, several endoscopic retrograde cholangiopancreatography-guided ablative modalities have emerged. Palliative photodynamic therapy, radiofrequency ablation, and intraluminal brachytherapy have been associated with improved stent patency and survival, although the ideal treatment approach remains unclear. This article reviews the published evidence for using each of these endobiliary ablative modalities in this difficult-to-treat patient population.


Assuntos
Neoplasias dos Ductos Biliares/terapia , Colangiocarcinoma/terapia , Colangiopancreatografia Retrógrada Endoscópica , Fotoquimioterapia/métodos , Ablação por Radiofrequência , Braquiterapia , Humanos , Fármacos Fotossensibilizantes/uso terapêutico , Radiologia Intervencionista
11.
Inflamm Bowel Dis ; 24(9): 2053-2061, 2018 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-29668917

RESUMO

BACKGROUND: Nonadherence to medications is common with patients with inflammatory bowel disease (IBD). The aim of this study was to assess adherence to biologic medications prescribed for IBD and to identify risk factors for biologic nonadherence. METHODS: This was a single center retrospective cohort study investigating IBD patient adherence to biologic therapies over a 2-year period from September 2014 to September 2016. Specialty pharmacy and infusion center records were obtained and a modified medication possession ratio was calculated. Patient characteristics associated with nonadherence in a univariate model were placed into a multivariate logistic regression to assess independent predictors of nonadherence. RESULTS: Three hundred sixty-five patients met inclusion criteria; 63 patients were on vedolizumab. Three hundred and one patients (82%) had Crohn's disease. The pooled 24-month adherence rate was 66%; adherence to individual biologic therapy included vedolizumab 83%, infliximab 70%, adalimumab 57%, and certolizumab pegol 50%. Facility-administered biologics were independently associated with higher adherence than self-administered biologics (OR 2.39, 95% CI 1.50 - 3.80). Additional risk factors for nonadherence included younger age (OR 1.22, 95% CI 1.01-1.47) and noncommercial insurance (OR 1.78, 95% CI 1.01 - 3.13). CONCLUSIONS: This is the first study to assess adherence to vedolizumab in IBD patients, which was higher than 3 other commonly prescribed biologic medications. Self-administered injections were strongly associated with biologic nonadherence. Younger age and noncommercial insurance also were associated with biologic nonadherence. Modality of administration should be taken into account when selecting a biologic agent for treatment of IBD.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Produtos Biológicos/uso terapêutico , Doença de Crohn/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Adalimumab/uso terapêutico , Adulto , Certolizumab Pegol/uso terapêutico , Doença de Crohn/psicologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/psicologia , Infliximab/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
12.
J Physiol ; 533(Pt 3): 849-59, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11410640

RESUMO

1. The purpose of these experiments was to use radiolabelled microspheres to measure blood flow distribution within the brain, and in particular to areas associated with motor function, maintenance of equilibrium, cardiorespiratory control, vision, hearing and smell, at rest and during exercise in miniature swine. Exercise consisted of steady-state treadmill running at intensities eliciting 70 and 100 % maximal oxygen consumption (V(O(2),max)). 2. Mean arterial pressure was elevated by 17 and 26 % above that at rest during exercise at 70 and 100 % V(O(2),max), respectively. 3. Mean brain blood flow increased 24 and 25 % at 70 and 100 % V(O(2),max), respectively. Blood flow was not locally elevated to cortical regions associated with motor and somatosensory functions during exercise, but was increased to several subcortical areas that are involved in the control of locomotion. 4. Exercise elevated perfusion and diminished vascular resistance in several regions of the brain related to the maintenance of equilibrium (vestibular nuclear area, cerebellar ventral vermis and floccular lobe), cardiorespiratory control (medulla and pons), and vision (dorsal occipital cortex, superior colliculi and lateral geniculate body). Conversely, blood flow to regions related to hearing (cochlear nuclei, inferior colliculi and temporal cortex) and smell (olfactory bulbs and rhinencephalon) were unaltered by exercise and associated with increases in vascular resistance. 5. The data indicate that blood flow increases as a function of exercise intensity to several areas of the brain associated with integrating sensory input and motor output (anterior and dorsal cerebellar vermis) and the maintenance of equilibrium (vestibular nuclei). Additionally, there was an intensity-dependent decrease of vascular resistance in the dorsal cerebellar vermis.


Assuntos
Circulação Cerebrovascular/fisiologia , Coração/fisiologia , Atividade Motora/fisiologia , Fenômenos Fisiológicos Respiratórios , Vestíbulo do Labirinto/fisiologia , Vias Visuais/fisiologia , Animais , Pressão Sanguínea/fisiologia , Temperatura Corporal/fisiologia , Colo/fisiologia , Gases/sangue , Frequência Cardíaca/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Suínos , Porco Miniatura , Resistência Vascular/fisiologia
13.
Brain Res ; 893(1-2): 292-300, 2001 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-11223021

RESUMO

The amino acid taurine serves many functions in the nervous system serving as inhibitory neurotransmitter/neuromodulator, neurotrophin, antioxidant, and osmolyte. Taurine levels are increased following brain injury and glucocorticoid administration. Thus, the purpose of this study was to examine spinal taurine concentrations following spinal cord injury (SCI) and methylprednisolone (MP) treatment of SCI. A total of 44 adult male Sprague-Dawley rats were divided into control and lesion groups. Control rats received a T6 vertebral laminectomy while lesioned rats received a laminectomy followed by complete spinal transection. Half of the animals in each group received MP intravenously following sham-operation or SCI. Rats survived for 7 or 30 days and concentrations of taurine in spinal gray and white matter, in spinal segments both near and distant from the injury epicenter, were resolved by HPLC analysis. Taurine levels were increased 7 and 30 days following transection in spinal segments immediately adjacent to the lesion and were further elevated by MP treatment. No increases were seen in far rostral/caudal segments, and MP treatment alone had no effect on spinal taurine levels. These findings demonstrate that spinal injury results in increased taurine concentrations in spinal segments undergoing the greatest degree of cellular reactivity and tissue reorganization and that MP therapy potentiates these increases. These findings are significant in that they further characterize the effects of acute MP therapy in spinal tissue. Since taurine is thought to be involved in neuroprotection and/or regeneration following injury, the potentiation of taurine levels by MP treatment may relate to its therapeutic properties.


Assuntos
Metilprednisolona/administração & dosagem , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/metabolismo , Taurina/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Injeções Intravenosas , Masculino , Ratos , Ratos Sprague-Dawley , Medula Espinal/química , Taurina/análise , Fatores de Tempo
14.
Neurosci Lett ; 291(1): 1-4, 2000 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-10962139

RESUMO

The glial enzyme glutamine synthetase (GS) is critical for central nervous system catabolism of glutamate and glutamine production. Upregulation of GS is a hallmark of reactive astrocytosis, although such induction following spinal cord injury (SCI) has not been reported. This study's purpose was to determine if GS activity is increased following SCI. Experimental rats received a complete spinal transection at the T5 segment and control rats received a laminectomy only. GS activities were determined using an enzymatic microassay. Glutamine levels were resolved in semi-adjacent sections. At 7 days following SCI, GS activity increased an average of 170-190% in white matter and 15-25% in gray matter immediately adjacent to the transection, and 70-90% in white matter and 40-45% in gray matter from cervical and lumbar enlargements. Correlative increases in glutamine were observed also. These findings further characterize the astrocytic response to SCI, which may contribute to altered glutamine metabolism in injured spinal tissue.


Assuntos
Glutamato-Amônia Ligase/metabolismo , Traumatismos da Medula Espinal/enzimologia , Medula Espinal/enzimologia , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Cromatografia Líquida de Alta Pressão , Glutamina/análise , Glutamina/metabolismo , Laminectomia , Região Lombossacral , Masculino , Pescoço , Ratos , Ratos Sprague-Dawley , Medula Espinal/química , Medula Espinal/patologia
15.
Otolaryngol Head Neck Surg ; 122(2): 195-200, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10652389

RESUMO

Squamous cell carcinomas were evaluated with respect to tumor differentiation (through use of hematoxylin and eosin stain), microvessel density (through use of CD-34 immunocytochemical stain), and magnitudes of malate dehydrogenase (MDH), hexokinase, and lactate dehydrogenase (LDH) enzyme activities. Direct correlations were found between tumor grade, MDH activity, and microvessel density. Direct correlations were also found between hexokinase activity and MDH activity and microvessel density. Inverse correlations were found between LDH activity and both tumor grade and MDH activity. These results suggest that the high rate of glucose utilization (indicated by hexokinase activity) found in more poorly differentiated tumors has a higher component of aerobic oxidative metabolism (indicated by MDH activity) and a relatively lower contribution from anaerobic metabolism (indicated by LDH activity) than do the rates found in more differentiated tumors. It is also suggested that as the glycolytic rate increases, more pyruvate goes into the Krebs cycle than into lactate. The availability of glucose-derived pyruvate for oxidative metabolism would mean less of a dependency on glutamine as a carbon source in squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/patologia , Hexoquinase/metabolismo , L-Lactato Desidrogenase/metabolismo , Malato Desidrogenase/metabolismo , Neoplasias Otorrinolaringológicas/enzimologia , Neoplasias Otorrinolaringológicas/patologia , Carcinoma de Células Escamosas/irrigação sanguínea , Humanos , Microcirculação/patologia , Neoplasias Otorrinolaringológicas/irrigação sanguínea
16.
Otolaryngol Head Neck Surg ; 119(5): 455-9, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9807068

RESUMO

Samples of tumor, tumor stroma, and mixed tumor and stroma were microdissected from three squamous cell carcinomas, as well as from adjacent nontumor tissue and assayed for malate dehydrogenase or lactate dehydrogenase activity as indicators of the relative contribution of aerobic and anaerobic processes, respectively, to energy metabolism. Malate and lactate dehydrogenase activities were greater in tumor tissue than in tumor stroma in all three tumors. However, the magnitudes of malate and lactate dehydrogenase activities were different among the tumors, suggesting that tumors vary in the degree to which aerobic and anaerobic reactions contribute to energy production. These results indicate that a quantitative assessment of enzymes involved in energy production may be a useful probe in the understanding of tumor metabolism.


Assuntos
Carcinoma de Células Escamosas/enzimologia , L-Lactato Desidrogenase/metabolismo , Malato Desidrogenase/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Metabolismo Energético , Humanos
17.
Artigo em Inglês | MEDLINE | ID: mdl-9579356

RESUMO

Body movement of guinea pigs was measured using a force platform at various times before and after unilateral end organ ablation and before and after sham surgery. Both spontaneous and drop-evoked movement patterns differed in the same animal after vestibular ablation and from control animals that received sham lesions. Whereas measures of eye nystagmus disappeared by 48 h postablation, measures of body movement indicated persistent differences even at 72 h. We conclude that the force platform can differentiate between movement patterns of normal and vestibular-lesioned animals and, in fact, measures a vestibular deficiency that is independent of eye nystagmus. The force platform appears to be a useful addition to evaluate vestibular deficits as well as to detect any benefits of pharmacological or surgical therapies.


Assuntos
Movimento , Nistagmo Patológico/etiologia , Núcleos Vestibulares/lesões , Análise de Variância , Animais , Cobaias , Nistagmo Patológico/fisiopatologia , Equilíbrio Postural , Núcleos Vestibulares/cirurgia
18.
Neurochem Res ; 20(12): 1483-90, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8789612

RESUMO

Homogenates of specific brain regions of three sensory systems (auditory, olfactory, and visual) were prepared from pigmented Long-Evans Hooded rats and assayed for amino acid concentrations and activities of glutaminase, aspartate aminotransferase (total, cytosolic, and by difference, mitochondrial), malate dehydrogenase, lactate dehydrogenase, and choline acetyltransferase. Comparing the quantitative distributions among regions revealed significant correlations between AAT and aspartate, between glutaminase and glutamate, between glutamate and glutamine, and between AAT plus glutaminase, or glutaminase alone, and the sum of aspartate, glutamate, and GABA, suggesting a metabolic pathway involving the synthesis of a glutamate pool as precursor to aspartate and GABA. Of the inhibitory transmitter amino acids, GABA concentrations routinely exceeded those of glycine, but glycine concentrations were relatively high in brainstem auditory structures.


Assuntos
Aminoácidos/análise , Córtex Auditivo/química , Condutos Olfatórios/química , Córtex Visual/química , Animais , Aspartato Aminotransferases/análise , Ácido Aspártico/análise , Córtex Auditivo/enzimologia , Colina O-Acetiltransferase/análise , Ácido Glutâmico/análise , Glutaminase/análise , L-Lactato Desidrogenase/análise , Malato Desidrogenase/análise , Condutos Olfatórios/enzimologia , Ratos , Distribuição Tecidual , Córtex Visual/enzimologia
19.
Brain Res ; 683(1): 140-8, 1995 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-7552338

RESUMO

The present study investigated the effect of seventh and eight cranial nerve lesions on the prominence of calcitonin gene-related peptide in the hypoglossal (XII), facial (VII), abducens (VI), and oculomotor (III) cranial nerve nuclei. Guinea pigs were anesthetized and subjected to unilateral cochlear removal, vestibular end organ ablation, and seventh nerve transection. After a survival period ranging from 4 h to 5 days, each animal was anesthetized and perfused intracardially. Frozen sections were collected through the brainstem and stained immunohistochemically for calcitonin gene-related peptide using a polyclonal antibody with the Vectastain ABC kit and protocol. Positive cells were counted in each nucleus bilaterally and analyzed for side to side differences. Nuclei XII and III showed no significant difference in the numbers of cells staining positively for calcitonin gene-related peptide between the ipsilateral and the contralateral sides to the lesion. However, nuclei VII and VI showed elevated numbers ipsilateral to the lesion on some days, but not all. For VII, there was no significant difference before 24 h, but there were significant differences 1-5 days after the lesion. Similarly, in VI, there was no difference before 24 h, but differences were significant beginning with day 1 and continuing through day 3, and finally disappearing by day 4. Changes in the numbers of CGRP positive cells in VII measurable 24 h after the lesion and continuing for at least 5 days afterward indicate a central nervous system retrograde response to peripheral motor nerve injury.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Tronco Encefálico/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Traumatismos do Nervo Facial , Traumatismos do Nervo Vestibulococlear , Nervo Abducente/metabolismo , Animais , Densitometria , Nervo Facial/metabolismo , Feminino , Cobaias , Nervo Hipoglosso/metabolismo , Imuno-Histoquímica , Masculino , Plasticidade Neuronal/fisiologia , Nervo Vestibulococlear/metabolismo
20.
Neurochem Res ; 19(6): 693-703, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7915016

RESUMO

The quantitative distributions of aspartate aminotransferase and glutaminase were mapped in subregions of olfactory bulb and cochlear nucleus of rat, and were compared with similar data for retina and with the distributions of their substrate and product amino acids aspartate, glutamate, and glutamine. The distributions of both enzymes paralleled that of aspartate in the olfactory bulb and that of glutamate in the cochlear nucleus. In retina (excluding inner segments), there were similarities between aspartate aminotransferase and both glutamate and aspartate distributions. The distribution of gamma-aminobutyrate (GABA) was similar to those of both enzymes in olfactory bulb, to aspartate aminotransferase in cochlear nucleus, and to glutaminase in retina (excluding inner segments). The results are consistent with significant involvement of aspartate aminotransferase, especially the cytosolic isoenzyme, and glutaminase in accumulation of the neurotransmitter amino acids glutamate, aspartate, and GABA, although with preferential accumulation of different amino acids in different brain regions.


Assuntos
Aminoácidos/metabolismo , Aspartato Aminotransferases/metabolismo , Núcleo Coclear/enzimologia , Glutaminase/metabolismo , Bulbo Olfatório/enzimologia , Retina/enzimologia , Animais , Ácido Aspártico/metabolismo , Núcleo Coclear/anatomia & histologia , Glutamatos/metabolismo , Ácido Glutâmico , Glutamina/metabolismo , Isoenzimas/metabolismo , Malato Desidrogenase/metabolismo , Bulbo Olfatório/anatomia & histologia , Especificidade de Órgãos , Ratos , Ratos Sprague-Dawley , Retina/anatomia & histologia , Ácido gama-Aminobutírico/metabolismo
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