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1.
Ophthalmol Sci ; 4(5): 100517, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881613

RESUMO

Purpose: Knowing the surgical safety of anterior chamber liquid biopsies will support the increased use of proteomics and other molecular analyses to better understand disease mechanisms and therapeutic responses in patients and clinical trials. Manual review of operative notes from different surgeons and procedures in electronic health records (EHRs) is cumbersome, but free-text software tools could facilitate efficient searches. Design: Retrospective case series. Participants: A total of 1418 aqueous humor liquid biopsies from patients undergoing intraocular surgery. Methods: Free-text EHR searches were performed using the Stanford Research Repository cohort discovery tool to identify complications associated with anterior chamber paracentesis and subsequent endophthalmitis. Complications of the surgery unrelated to the biopsy were not reviewed. Main Outcome Measures: Biopsy-associated intraoperative complications and endophthalmitis. Results: A total of 1418 aqueous humor liquid biopsies were performed by 17 experienced surgeons. EHR free-text searches were 100% error-free for surgical complications, >99% for endophthalmitis (<1% false positive), and >93.6% for anesthesia type, requiring manual review for only a limited number of cases. More than 85% of cases were performed under local anesthesia without ocular muscle akinesia. Although the most common indication was cataract (50.1%), other diagnoses included glaucoma, diabetic retinopathy, uveitis, age-related macular degeneration, endophthalmitis, retinitis pigmentosa, and uveal melanoma. A 50- to 100-µL sample was collected in all cases using either a 30-gauge needle or a blunt cannula via a paracentesis. The median follow-up was >7 months. There was only one minor complication (0.07%) identified: a case of a small tear in Descemet membrane without long-term sequelae. No other complications occurred, including other corneal injuries, lens or iris trauma, hyphema, or suprachoroidal hemorrhage. There was no case of postoperative endophthalmitis. Conclusions: Anterior chamber liquid biopsy during intraocular surgery is a safe procedure and may be considered for large-scale collection of aqueous humor samples for molecular analyses. Free-text EHR searches are an efficient approach to reviewing intraoperative procedures. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

2.
Cell ; 186(22): 4868-4884.e12, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37863056

RESUMO

Single-cell analysis in living humans is essential for understanding disease mechanisms, but it is impractical in non-regenerative organs, such as the eye and brain, because tissue biopsies would cause serious damage. We resolve this problem by integrating proteomics of liquid biopsies with single-cell transcriptomics from all known ocular cell types to trace the cellular origin of 5,953 proteins detected in the aqueous humor. We identified hundreds of cell-specific protein markers, including for individual retinal cell types. Surprisingly, our results reveal that retinal degeneration occurs in Parkinson's disease, and the cells driving diabetic retinopathy switch with disease stage. Finally, we developed artificial intelligence (AI) models to assess individual cellular aging and found that many eye diseases not associated with chronological age undergo accelerated molecular aging of disease-specific cell types. Our approach, which can be applied to other organ systems, has the potential to transform molecular diagnostics and prognostics while uncovering new cellular disease and aging mechanisms.


Assuntos
Envelhecimento , Humor Aquoso , Inteligência Artificial , Biópsia Líquida , Proteômica , Humanos , Envelhecimento/metabolismo , Humor Aquoso/química , Biópsia , Doença de Parkinson/diagnóstico
3.
J Vis Exp ; (199)2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37747194

RESUMO

A critical challenge in translational research is establishing a viable and efficient interface between patient care in the operating room (OR) and the research laboratory. Here, we developed a protocol for acquiring high-quality liquid biopsies for molecular analyses from the aqueous humor and the vitreous from patients undergoing eye surgery. In this workflow, a Mobile Operating Room Lab Interface (MORLI) cart equipped with a computer, a barcode scanner, and lab instruments, including onboard cold storage, is used to obtain and archive human biological samples. A web-based data privacy-compliant database enables annotating each sample over its lifetime, and a cartesian coordinate system allows tracking each barcoded specimen in storage, enabling quick and accurate retrieval of samples for downstream analyses. Molecular characterization of human tissue samples not only serves as a diagnostic tool (e.g., to distinguish between infectious endophthalmitis and other non-infectious intraocular inflammation) but also represents an important component of translational research, allowing the identification of new drug targets, development of new diagnostic tools, and personalized therapeutics.


Assuntos
Bancos de Espécimes Biológicos , Endoftalmite , Humanos , Corpo Vítreo , Humor Aquoso , Biópsia Líquida
4.
Transl Vis Sci Technol ; 10(8): 17, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34264294

RESUMO

Purpose: Nonarteritic anterior ischemic optic neuropathy (NAION) is a common acute optic neuropathy in those older than 50 years. There is no blood diagnostic test or efficient treatment for NAION. We investigated the suitability of blood inflammatory proteins as biomarkers and therapeutic targets of NAION. Methods: We conducted an exploratory, cross-sectional case-control study including 18 patients with NAION (n = 5 acute, and n = 13 chronic) and 9 controls. NAION was confirmed by clinical examination and optical coherence tomography. Subjects underwent peripheral blood collection; plasma was isolated within 2 hours and analyzed using a 76-plex array of cytokines, chemokines, and growth factors. Results: In acute NAION, there was increased peripapillary retinal thickness on optical coherence tomography consistent with optic disc edema. Plasma profiling revealed dramatic changes in inflammatory proteins in NAION. Statistical analysis generated a list of 20 top-ranked molecules in NAION, with 15% overlap in acute and chronic NAION. Principal component analysis, hierarchical clustering, and Spearman correlation generally segregated controls, acute and chronic NAION, with some overlap. Longitudinal data from one patient demonstrated an evolving inflammatory pattern from acute to chronic NAION. In acute NAION, Eotaxin-3, MCP-2, TPO, and TRAIL were the top biomarker candidates. In chronic NAION, IL-1α and CXCL10 emerged as the strongest therapeutic targets. Conclusions: Post-NAION inflammation occurs in both acute and chronic NAION. Statistical analysis of plasma profile changes generated a list of 20 potential biomarker and therapeutic targets of NAION. Translational Relevance: We identified blood molecular targets to improve NAION diagnosis and treatment.


Assuntos
Disco Óptico , Neuropatia Óptica Isquêmica , Estudos de Casos e Controles , Estudos Transversais , Humanos , Fibras Nervosas , Neuropatia Óptica Isquêmica/diagnóstico , Células Ganglionares da Retina , Acuidade Visual , Campos Visuais
5.
Acta Psychiatr Scand ; 138(3): 267-273, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29959765

RESUMO

OBJECTIVE: We conducted a 12-week double-blind study of stabilization pharmacotherapy in patients with remitted psychotic depression (PD). METHODS: Seventy-one persons aged 18 years or older who had achieved remission of PD when randomized to either olanzapine plus sertraline or olanzapine plus placebo were continued on the double-blind treatment associated with remission. Symptoms of depression and psychosis, and weight, were measured once every 4 weeks. Cholesterol, triglycerides, and glucose were measured at stabilization phase baseline and Week 12/termination. RESULTS: The effect of treatment did not significantly change with time for depression, weight, or metabolic measures in the stabilization phase. Eight of the 71 participants (11.3%; 95% CI: 5.8, 20.7) experienced a relapse of major depression, psychosis, or both. Treatment groups did not differ in the frequency of relapse. In the entire study group, the adjusted estimate for change in weight was an increase of 1.66 kg (95% CI: 0.83, 2.48) and the adjusted estimate for change in total cholesterol was a decrease of 14.8 mg/dL (95% CI: 3.5, 26.1) during the 12-week stabilization phase; the remaining metabolic measures did not significantly change. CONCLUSION: Continuation of acute treatment was associated with stability of remission.


Assuntos
Transtorno Depressivo Maior/tratamento farmacológico , Olanzapina/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Sertralina/uso terapêutico , Adulto , Idoso , Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , Glicemia/análise , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Transtorno Depressivo Maior/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina/administração & dosagem , Placebos/administração & dosagem , Indução de Remissão/métodos , Sertralina/administração & dosagem , Triglicerídeos/sangue
6.
J Invest Surg ; 29(5): 260-5, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27010523

RESUMO

OBJECTIVE: Postoperative adhesions are among the major causes of morbidity and mortality following abdominal surgery. As an antioxidant and antiinflamatory agent, the potential effect of ethyl pyruvate on adhesion prevention has not been clearly studied. We aimed to investigate the possible anti-adhesive effect of ethyl pyruvate compared with an effective barrier membrane, Seprafilm, in a rat cecal abrasion model. MATERIALS AND METHODS: Male Wistar albino rats separated into three adhesion model groups (n = 8, each) with applications of different agents during surgery: control (intraperitoneal normal saline), Seprafilm group (intraperitoneal Seprafilm), and Ethyl pyruvate group (40 mg/kg intraperitoneal ethyl pyruvate). Postoperative adhesion was graded both macroscopically and histopathologically. Malondialdehyde and nitric oxide levels were determined from tissue samples for assessment of oxidative stress. RESULTS: Seprafilm and Ethyl pyruvate groups had lower adhesion scores (both macroscopic and microscopic) and decreased malondialdehyde and nitric oxide levels compared to the control group (p < 0.05 for all parameters). The results were comparable for both Seprafilm and Ethyl pyruvate groups for all parameters (p > 0.05). CONCLUSIONS: Intraperitoneal ethyl pyruvate application reduced the incidence and the extent of postoperative adhesions in rat cecal abrasion model. Ethyl pyruvate also had comparable overall efficacy for adhesion prevention as Seprafilm.


Assuntos
Piruvatos/administração & dosagem , Aderências Teciduais/prevenção & controle , Animais , Antioxidantes/administração & dosagem , Materiais Biocompatíveis , Ceco/lesões , Ceco/metabolismo , Ceco/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Modelos Animais de Doenças , Ácido Hialurônico , Injeções Intraperitoneais , Masculino , Malondialdeído/metabolismo , Membranas Artificiais , Óxido Nítrico/metabolismo , Ratos , Ratos Wistar , Aderências Teciduais/etiologia , Aderências Teciduais/patologia
8.
Case Rep Pathol ; 2015: 461420, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26064749

RESUMO

Although neuroendocrine tumours (NETs) of primary hepatic origin are extremely rare, most of NETs present with liver metastasis. When a NET is found in the liver, it must be treated to exclude metastasis from extrahepatic primary sites. The patient was a 38-year-old female. Abdominal ultrasound showed an 8 cm tumour in liver during a routine examination. Liver biopsy was done. The tumour was first considered a metastatic hepatic tumour on histopathological examination. No clues to the origin of a primary tumour were found. Upper and lower endoscopy of the GI tract and chest CT were performed to search for a primary tumour and were negative for any tumour. One month later, more extensive areas of the tumour were seen on histopathological examination of second liver biopsy with the same morphologic characteristics as the first biopsy. Immunohistochemically, there was positive staining for synaptophysin, CD 56, and S-100 in the tumour cells. These findings suggested the diagnosis of NET. The diagnosis of primary liver NET was considered in a multidisciplinary meeting. Then, left hepatectomy was performed. The final pathologic diagnosis of the tumour in the resected liver specimen was Grade II NET. The patient was doing well at postoperative 28-month follow-up.

9.
Front Cell Neurosci ; 8: 253, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25225472

RESUMO

AIM: Behavioral and mental changes may occur in people exposed to cold stress by decreasing their work efficiency and their mental capacity while increasing the number of accidents on the job site. The goal of this study was to explore the effect of cold stress in spatial learning performance excitability and LTP. MATERIALS AND METHODS: Three to four month old rats were randomly divided into four groups to form a control group and a cold stress group for each sex. The groups of cold stressed animals were placed in a cold room ambient temperature of 4°C for 2 h day. Adrenal glands and body weight (g) were recorded in control and stressed rats during the cold exposure. Spatial learning (acquisition phase) and memory (probe trial) were tested in the Morris water maze (MWM) immediately after daily exposure. Latency to locate the hidden platform, distance moved (DM), mean distance to platform, swim speed (SS) and time spent in the platform quadrant were compared between genders and treatments. Field potential recordings were made, under urethane anesthesia, from the dentate gyrus (DG) granule-cell layer, with stimulation of the medial perforant pathway 2 h after the probe trial. This study examined spatial memory as measured by MWM performance and hippocampal long-term potentiation (LTP) in the DG after exposure to cold in a repeated stress condition for 2 h/day for 5 days. RESULTS: The cold-exposed female rats needed less time to find the hidden platform on day 1 (43.0 ± 13.9 s vs. 63.2 ± 13.2 s), day 2 (18.2 ± 8.4 s vs. 40.9 ± 12.2 s) and on day 4 (8.0 ± 2.1 s vs. 17.2 ± 7.0 s) while cold-exposed male rats showed a decreased escape latency (EL) on day 1 only (37.3 ± 12.5 s vs. 75.4 ± 13.1 s). Cold-exposed male rats spent less time in the target quadrant (30.08 ± 6.11%) than the control male rats (37.33 ± 8.89%). Two hour cold exposure decreased population spike (PS) potentiation during both induction (218.3 ± 21.6 vs. 304.5 ± 18.8%) and maintenance intervals (193.9 ± 24.5 vs. 276.6 ± 25.4%) in male rats. Meanwhile cold exposure did not affect the body weight (C: 221 ± 2.5 vs. S: 222 ± 1.7) but it impacts the adrenal gland relative weight (S: 27.1 ± 1.8 mg vs. C: 26.2 ± 1.4 mg). CONCLUSION: Overall, the results show that repeated cold exposure can selectively improve spatial learning in adult female rats, but impaired retention memory for platform location in male rats. It is possible that impaired LTP underlies some of the impaired retention memory caused by cold exposure in the male rats.

10.
J Matern Fetal Neonatal Med ; 26(15): 1532-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23544882

RESUMO

AIM: We aimed to evaluate the deformability characteristics of RBC and the affecting factors in newborns diagnosed with congenital hypothyroidism (CH) and to compare the outcomes after the L-thyroxin treatment. PATIENTS AND METHODS: Enrolled subjects were divided into two subgroups as "patients" and age-matched healthy "controls". First blood samples were taken from all subjects for measuring elongation index (rEI) and osmotic fragility of RBC (OF), hematic and biochemical analytes affecting the RBC deformability in the neonatal age. All parameters were repeated a month after provided euthyroid state following the treatment in patients and age-matched healthy controls. RESULTS: There was no difference between both groups in terms of complete blood count parameters and serum analytes (albumin, bilirubin and fibrinogen) except expected age-related changes in the first and second readings. Serum lipid/lipoprotein levels of both groups remained unchanged except triglyceride levels during the study period. The rEI of the patients were lower than that of controls in the first and second readings. The rEIs of the patients became increased, reaching (not equal) the levels of their controls during L-thyroxin treatment. Osmotic fragility of the patients was detected as lower than controls in the first and second readings, and became better during L-thyroxin treatment. CONCLUSION: Our results indicate that some changes may occur on the hematic and biochemical analytes affecting the RBC deformability features. Neonates with CH have the worst rEI initially, but they reached the indices of the healthy infants thanks to L-thyroxin treatment. Also, their OF features have been improved by L-thyroxin.


Assuntos
Hipotireoidismo Congênito/sangue , Hipotireoidismo Congênito/tratamento farmacológico , Eritrócitos/fisiologia , Hemorreologia , Tiroxina/uso terapêutico , Índices de Eritrócitos , Feminino , Humanos , Recém-Nascido , Masculino , Fragilidade Osmótica/efeitos dos fármacos , Estudos Prospectivos , Tireotropina/sangue , Tiroxina/sangue
11.
Brain Res ; 1482: 32-9, 2012 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-22981414

RESUMO

Omega-3 fatty acid deprivation during development reduces performance in learning tasks, and dietary DHA supplementation improves learning ability and enhances long term memory in both young and old animals. However, little attention has been paid to the effect of maternal intake of Omega-3 fatty acids on hippocampal function in their pups. Randomly some of the pregnant dams were supplemented with Omega-3 essential fatty acid, others with tap-water, during pregnancy and breast-feeding by gavage daily. Spatial learning and memory was tested in Morris water maze. Field potentials from the dentate gyrus were recorded in response to medial perforant pathway in urethane-anesthetized pups. Omega-3-treated rats found the platform less traveled and closer to platform than control animals. However the pups from both groups show the same performance in retrieval task. No differences were found between corresponding animal groups in the input-output curves of the field potential slopes, suggesting no effect of Omega-3 supplementation on basal synaptic efficacy. Potentiation of population spike amplitude was much higher in pups of Omega-3 treated dams than control. Up to now Omega 3 fatty acid has been shown to be beneficial on the synaptic plasticity only under some pathological conditions. For the first time, we showed improved dentate gyrus-LTP and enhanced Morris water maze performance in healthy pups from healthy dams treated with Omega-3 fatty acids during pregnancy and breast-feeding period. Molecular studies are needed to explain Omega-3 effect on hippocampal synaptic plasticity.


Assuntos
Giro Denteado/efeitos dos fármacos , Suplementos Nutricionais , Ácidos Graxos Ômega-3/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição/efeitos dos fármacos , Análise de Variância , Animais , Biofísica , Giro Denteado/fisiologia , Estimulação Elétrica , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Lateralidade Funcional , Masculino , Troca Materno-Fetal/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Via Perfurante/fisiologia , Gravidez , Ratos , Ratos Wistar , Fatores de Tempo
12.
J Neuroendocrinol ; 24(3): 422-33, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22070634

RESUMO

Manipulations of thyroid hormones have been shown to influence learning and memory. Although a large body of literature is available on the effect of thyroid hormone deficiency on learning and memory functions during the developmental stage, electrophysiological and behavioural findings, particularly on propylthiouracil administration to adult normothyroid animals, are not satisfactory. The experiments in the present study were carried out on 12 adult male Wistar rats aged 6-7 months. Hypothyroidism was induced by administering 6-n-propyl-2-thiouracil in their drinking water for 21 days at a concentration of 0.05%. The spatial learning performance of hypothyroid and control rats was studied on a Y-maze. The rats were then placed in a stereotaxic frame under urethane anaesthesia. A bipolar tungsten electrode was used to stimulate the medial perforant path. A glass micropipette was inserted into the granule cell layer of the ipsilateral dentate gyrus to record field excitatory post-synaptic potentials. After a 15-min baseline recording of field potentials, long-term potentiation was induced by four sets of tetanic trains. The propylthiouracil-treated rats showed a significantly attenuated input-output (I/O) relationship when population spike (PS) amplitudes and field excitatory post-synaptic potentials (fEPSP) were compared. fEPSP and PS latencies were found to be longer in the hypothyroid group than in the control group. The PS amplitude and fEPSP slope potentiations in the hypothyroid rats were not statistically different from those in the control rats, except for the field EPSP slope measured in the post-tetanic and maintenance phases. The hypothyroid rats also showed lower thyroxine levels and poor performance in the spatial memory task. The present study provides in vivo evidence for the action of propylthiouracil leading to impaired synaptic plasticity, which might explain deficit in spatial memory tasks in adult hypothyroid rats.


Assuntos
Giro Denteado/fisiopatologia , Potenciais Pós-Sinápticos Excitadores , Hipocampo/fisiopatologia , Hipotireoidismo/fisiopatologia , Potenciação de Longa Duração , Aprendizagem em Labirinto , Animais , Masculino , Ratos , Ratos Wistar , Tiroxina/sangue
13.
Neuroendocrinology ; 94(3): 218-27, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21778690

RESUMO

BACKGROUND: Manipulating thyroid hormones has been shown to influence learning and memory. Although a large body of literature is available on the effects of thyroid hormone deficiency on learning and memory functions during developmental or adult-onset hypothyroidism, electrophysiological findings are limited. This limitation is especially notable with respect to thyroxine administration in adult, normothyroid animals. METHODS: Experiments were carried out on 12 adult male Wistar rats, each 9-10 months of age. Rats were randomly divided into hyperthyroid (0.2 mg/kg/day intraperitoneal thyroxine injection, for 21 days) and control groups (n = 6 animals in each group). Following spatial learning performance tests on hyperthyroid and control groups, rats were anesthetized with urethane and placed in a stereotaxic frame. A bipolar, tungsten electrode was used to stimulate the medial perforant path. A glass micropipette was inserted within the granule cell layer of the ipsilateral dentate gyrus to record field excitatory postsynaptic potentials (fEPSP). Following a 15-min baseline recording of fEPSPs, long-term potentiation (LTP) was induced by four sets of tetanic pulse trains. RESULTS: Thyroxine-treated rats showed significantly worse performance in the spatial memory task and attenuated input-output relationships in the electrophysiological analyses. Treated rats also showed a lower efficacy of LTP induction when compared with controls. CONCLUSION: The present study provides clear in vivo evidence for the action of L-thyroxine in the impairment of synaptic plasticity and in inducing spatial memory task deficits in adult rats. These findings may explain the complaints of cognitive function reductions in hyperthyroid patients.


Assuntos
Hipocampo/efeitos dos fármacos , Hipertireoidismo/induzido quimicamente , Hipertireoidismo/fisiopatologia , Potenciação de Longa Duração/efeitos dos fármacos , Tiroxina/efeitos adversos , Fatores Etários , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Modelos Animais de Doenças , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Hipocampo/fisiologia , Hipertireoidismo/sangue , Potenciação de Longa Duração/fisiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/sangue , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/fisiopatologia , Ratos , Ratos Wistar , Hormônios Tireóideos/sangue , Tiroxina/farmacologia
14.
Neurosci Res ; 70(1): 71-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21256900

RESUMO

Some evidence suggests that sleep deprivation might impair synaptic plasticity and produce oxidative stress in the hippocampus. However it is not clear whether impairment of long-term potentiation depends on the oxidative stress evoked by sleep deprivation protocol. In this study we aimed to investigate the effects of a 21-day sleep deprivation period on long-term plasticity taking into account the stressful effect of sleep deprivation. Sleep deprivation was carried out using the multiple platforms method on adult male Wistar rats. Long-term potentiation was studied in the medial perforant pathway-dentate gyrus synapses. Elevated T test was applied, and blood corticosterone levels were measured. Lipid peroxidation products in whole brain and hippocampus were determined. No significant difference was found between the sleep deprived, pedestal and cage control groups at the end of the 21-day period when corticosterone levels were compared. The results of the elevated T test indicated that sleep deprivation did not change the anxiety-like behavior of the animals. When compared with cage or pedestal control groups, sleep deprived rats displayed elevated malondialdehyde levels, and decreased superoxide dismutase and glutathione peroxidase activities together with impaired long-term potentiation maintenance. It can be argued that 21-day SD may impair the maintenance of long-term potentiation evoked in the dentate gyrus, and the balance between oxidant and antioxidant defenses of the hippocampus.


Assuntos
Giro Denteado/metabolismo , Giro Denteado/fisiopatologia , Potenciação de Longa Duração/fisiologia , Estresse Oxidativo/fisiologia , Privação do Sono/metabolismo , Privação do Sono/fisiopatologia , Animais , Doença Crônica , Masculino , Oxirredução , Ratos , Ratos Wistar , Tempo
15.
Neuropeptides ; 45(1): 77-81, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21163526

RESUMO

Carnosine is a dipeptide synthesized by the carnosine synthetase from ß-alanine and l-histidine. The well-known effects of carnosine may be related with mechanisms producing long-term potentiation which is one of the electrophysiological signs of memory. In the present study we aimed to investigate the effect of four different doses of carnosine on long-term potentiation in urethane-anesthetized rat. A bipolar stimulating electrode was placed in the medial perforant path and a double-barrel glass micropipette was placed in the dentate gyrus as the recording electrode. Artificial cerebrospinal fluid (in the control group) or carnosine (0.1, 1, 10, and 100µg/µL) was infused into the dentate gyrus. Our results showed that the I/O curve of the excitatory postsynaptic potential slope or population spike amplitude was not significantly shifted by carnosine. We found that population spike amplitude increased to 244% and 287% at the dose of 100µg/µL in the post-tetanic and induction phases, respectively, but decreased to 163% and 186% at the dose of 0.1µg/µL and to 145% and 162% at the dose of 1µg/µL when compared with 203% and 232% of the control values. However, there were no significant differences for the slope of excitatory postsynaptic potential. Carnosine had no effect on the EPSP slope or PS amplitude recorded from the dentate gyrus in response to test stimuli when high-frequency stimulation was not delivered. In the present study, we speculated that the effects of carnosine in lower or higher doses could be explained by its effect on different processes, such as soluble guanylyl cyclase inhibition or the conversion of carnosine into histamine.


Assuntos
Anestésicos Intravenosos/farmacologia , Carnosina/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Uretana/farmacologia , Animais , Giro Denteado/efeitos dos fármacos , Giro Denteado/fisiologia , Eletrofisiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Masculino , Ratos , Ratos Wistar
16.
Clin Hemorheol Microcirc ; 45(2-4): 329-36, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20675916

RESUMO

Currently, with reappraisal of ozone therapy, it has been utilized worldwide in research and clinical field. Most of the studies investigating effects of ozone on blood parameters are conducted by directly ozonating the blood. Rectal insufflation is a simple, easy and inexpensive method of delivering ozone. Little is known how these gases affect some fundamental hemorheologic parameters when given by insufflation. We aimed to investigate the effects of colorectally insufflated oxygen-ozone on red blood cell rheology in rabbits. Rabbits were divided into Group 1 (control); Groups 2, 3 and 4 (oxygen rectally insufflated respectively for 15, 21 and 36 days); Groups 5, 6 and 7 (ozone rectally insufflated respectively for 15, 21 and 36 days). Erythrocyte deformability, aggregation and osmotic fragility were determined from blood samples at the end of each treatment period. Our study showed an improvement in deformability, a decrease in aggregation and an increase in fragility following a 15 day ozone treatment. With longer ozone application the changes in aggregation and fragility returned back to control levels, however its effect on deformability sustained. Therefore, more than two weeks ozone insufflation may induce adaptation to changes induced by ozone suggesting its systemic effects.


Assuntos
Eritrócitos/efeitos dos fármacos , Hemorreologia/efeitos dos fármacos , Ozônio/farmacologia , Animais , Agregação Eritrocítica/efeitos dos fármacos , Deformação Eritrocítica/efeitos dos fármacos , Insuflação , Fragilidade Osmótica/efeitos dos fármacos , Ozônio/administração & dosagem , Coelhos , Reto
17.
HPB (Oxford) ; 11(3): 252-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19590656

RESUMO

OBJECTIVES: This study aimed to illustrate the indications for, and types and outcomes of surgical portosystemic shunt (PSS) and/or Rex bypass in a single centre. METHODS: Data were collected from children with a PSS and/or Rex bypass between 1992 and 2006 at Mount Sinai Medical Center, New York. RESULTS: Median age at surgery was 10.7 years (range 0.3-22.0 years). Indications included: (i) refractory gastrointestinal bleeding in portal hypertension associated with (a) compensated cirrhosis (n= 12), (b) portal vein thrombosis (n= 10), (c) hepatoportal sclerosis (n= 3); (ii) refractory ascites secondary to Budd-Chiari syndrome (n= 3), and (iii) familial hypercholesterolaemia (n= 4). There were 20 distal splenorenal, four portacaval, three Rex bypass, two mesocaval, two mesoatrial and one proximal splenorenal shunts. At the last follow-up (median 2.9 years, range 0.1-14.1 years), one shunt (Rex bypass) was thrombosed. Two patients had died and two had required a liver transplant. These had a patent shunt at last imaging prior to death or transplant. CONCLUSIONS: Portosystemic shunts and Rex bypass have been used to manage portal hypertension with excellent outcomes. In selected children with compensated liver disease, PSS may act as a bridge to liver transplantation or represent an attractive alternative.

18.
J Cataract Refract Surg ; 32(5): 795-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16765797

RESUMO

PURPOSE: To evaluate the efficacy, predictability, and safety of Visx CustomVue wavefront-guided enhancement after previous keratorefractive surgery. SETTING: Stanford University Eye Laser Center, Stanford, California, USA. METHODS: A retrospective analysis was used to evaluate wavefront-guided enhancement in a preliminary set of 120 eyes of 102 patients. All eyes had previous keratorefractive surgery (photorefractive keratoplasty [PRK] in 1 eye, laser in situ keratomileusis [LASIK] in 119 eyes); the prekeratorefractive surgery spherical equivalent (SE) refraction ranged from -1.25 diopters (D) to -7.00 D. Primary outcome variables including uncorrected visual acuity (UCVA), manifest refraction, and complications were evaluated at 1 and 3 months. RESULTS: At 1 month, the mean pre-enhancement SE was reduced from -0.91 D +/- 0.40 (SD) (range -2.375 to -0.125 D) to -0.13 +/- 0.33 D (range -1.25 to 0.75 D) with 91% of eyes within +/-0.5 D of emmetropia and 100% within +/-1.0 D. All eyes showed equal or improved UCVA (range 20/15 to 20/30) with 20/20 or better in 84 of 91 eyes. At 3 months, the mean was -0.20 +/- 0.32 D (range -0.75 to 0.75 D) with 100% of eyes within +/-0.75 D of emmetropia. All eyes showed equal or improved UCVA (range 20/15 to 20/30) with 20/20 or better in 74 of 84 eyes. Higher-order wavefront aberration analysis showed that the mean root-mean-square error was reduced from 0.39 +/- 0.14 microm (range 0.16 to 0.86 microm) to 0.34 +/- 0.12 microm (range 0.12 to 0.78 microm). Coma was reduced from 0.22 +/- 0.13 microm (range 0.02 to 0.71 microm) to 0.16 +/- 0.11 microm (range 0.01 to 0.62 microm), and trefoil was reduced from 0.16 +/- 0.09 microm (range 0.01 to 0.62 microm) to 0.11 +/- 0.07 microm (range 0.01 to 0.27 microm). Spherical aberration was unchanged from 0.14 +/- 0.14 microm (range -0.18 to 0.59 microm) to 0.14 +/- 0.14 microm (range -0.16 to 0.5 microm). CONCLUSION: Preliminary data show that Visx CustomVue wavefront-guided enhancement after keratorefractive surgery is an effective, predictable, and safe procedure.


Assuntos
Córnea/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Miopia/cirurgia , Adulto , Idoso , Córnea/fisiopatologia , Feminino , Humanos , Complicações Intraoperatórias , Lasers de Excimer , Masculino , Pessoa de Meia-Idade , Miopia/fisiopatologia , Ceratectomia Fotorrefrativa , Complicações Pós-Operatórias , Refração Ocular/fisiologia , Reoperação , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual/fisiologia
19.
Eur J Pharmacol ; 403(1-2): 17-25, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10969139

RESUMO

alpha-amidation of a peptide (which takes place from a glycine-extended precursor) is required to produce biologically active amidated hormones, such as gastrin-releasing peptide (GRP)/Pyr-Gln-Arg-Leu-Gly-Asn-Gln-Trp-Ala-Val-Gly-His-Leu-Met-NH(2) (bombesin). It was shown that glycine-extended gastrin mediates mitogenic effects on various cell lines by interacting with a specific receptor, different from the classical CCK(1) or CCK(2) receptors. On the basis of this observation, we have extended the concept of obtaining active glycine-extended forms of others amidated peptides to produce new active analogues. In this study, we have tested the biological behaviour of a synthetic analogue of the glycine-extended bombesin (para-hydroxy-phenyl-propionyl-Gln-Trp-Ala-Val-Gly-His-Leu-Met-Gly-OH or JMV-1458) on various in vitro models. We showed that compound JMV-1458 was able to inhibit specific (3-[125I]iodotyrosyl(15)) GRP ([125I]GRP) binding in rat pancreatic acini and in Swiss 3T3 cells with K(i) values of approximately 10(-8) M. In isolated rat pancreatic acini, we found that JMV-1458 induced inositol phosphates production and amylase secretion in a dose-dependent manner. In Swiss 3T3 cells, the glycine-extended bombesin analogue dose-dependently produced [3H]thymidine incorporation. By using potent GRP/bombesin receptor antagonists, we showed that this synthetic glycine-extended bombesin analogue induces its biological activities via the classical GRP/bombesin receptor.


Assuntos
Bombesina/análogos & derivados , Bombesina/metabolismo , Receptores da Bombesina/metabolismo , Células 3T3 , Amilases/efeitos dos fármacos , Amilases/metabolismo , Animais , Ligação Competitiva/efeitos dos fármacos , Bombesina/química , Bombesina/farmacologia , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fosfatos de Inositol/metabolismo , Radioisótopos do Iodo , Masculino , Camundongos , Pâncreas/citologia , Pâncreas/metabolismo , Ratos , Ratos Wistar
20.
J Pept Res ; 53(3): 275-83, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10231715

RESUMO

Bombesin receptor antagonists are potential therapeutic agents due to their ability to act as inhibitors of cellular proliferation. On the basis of our hypothesis concerning the mechanism of action of gastrin associating an activating enzyme to the receptor and on the results reported in the literature, we have synthesized bombesin analogs which have been modified in the C-terminal part. Potent bombesin receptor antagonists were obtained by replacement of Leu-13 with a statyl residue or with a residue bearing an hydroxyl group in place of the carbonyl function of Leu-13. Several inhibitors were able to recognize the bombesin receptor on rat pancreatic acini and antagonized bombesin stimulated amylase secretion in the nanomolar range. These compounds were also able to recognize the bombesin receptor and to inhibit [3H] thymidine incorporation in 3T3 cells with the same potency.


Assuntos
Compostos Organofosforados/síntese química , Receptores da Bombesina/antagonistas & inibidores , Células 3T3 , Amilases/metabolismo , Animais , Relação Dose-Resposta a Droga , Concentração Inibidora 50 , Cinética , Camundongos , Modelos Químicos , Pâncreas/efeitos dos fármacos , Ratos , Timidina/metabolismo
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