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1.
Int J Mol Sci ; 24(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36768336

RESUMO

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a disabling multisystem illness in which individuals are plagued with fatigue, inflammatory symptoms, cognitive dysfunction, and the hallmark symptom, post-exertional malaise. While the cause of this disease remains unknown, there is evidence of a potential infectious component that, along with patient symptoms and common onsets of the disease, implicates immune system dysfunction. To further our understanding of the state of ME/CFS lymphocytes, we characterized the role of fatty acids in isolated Natural Killer cells, CD4+ T cells, and CD8+ T cells in circulation and after overnight stimulation, through implicit perturbations to fatty acid oxidation. We examined samples obtained from at least 8 and as many as 20 subjects for immune cell fatty acid characterization in a variety of experiments and found that all three isolated cell types increased their utilization of lipids and levels of pertinent proteins involved in this metabolic pathway in ME/CFS samples, particularly during higher energy demands and activation. In T cells, we characterized the cell populations contributing to these metabolic shifts, which included CD4+ memory cells, CD4+ effector cells, CD8+ naïve cells, and CD8+ memory cells. We also discovered that patients with ME/CFS and healthy control samples had significant correlations between measurements of CD4+ T cell fatty acid metabolism and demographic data. These findings provide support for metabolic dysfunction in ME/CFS immune cells. We further hypothesize about the consequences that these altered fuel dependencies may have on T and NK cell effector function, which may shed light on the illness's mechanism of action.


Assuntos
Síndrome de Fadiga Crônica , Ácidos Graxos , Linfócitos , Humanos , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Síndrome de Fadiga Crônica/imunologia , Células Matadoras Naturais , Ácidos Graxos/imunologia , Oxirredução , Metabolismo dos Lipídeos/imunologia , Linfócitos/imunologia , Subpopulações de Linfócitos/imunologia
2.
Am J Epidemiol ; 185(8): 617-626, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28338983

RESUMO

In the Multi-Site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM), we relied on expert clinician diagnoses to enroll patients from 7 specialty clinics in the United States in order to perform a systematic collection of data on measures of myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS). Healthy persons and those with other illnesses that share some features with ME/CFS were enrolled in comparison groups. The major objectives were to: 1) use standardized questionnaires to measure illness domains of ME/CFS and to evaluate patient heterogeneity overall and between clinics; 2) describe the course of illness, identify the measures that best correlate with meaningful clinical differences, and assess the performances of questionnaires as patient/person-reported outcome measures; 3) describe prescribed medications, orders for laboratory and other tests, and management tools used by expert clinicians to care for persons with ME/CFS; 4) collect biospecimens for future hypothesis testing and for evaluation of morning cortisol profiles; and 5) identify measures that best distinguish persons with ME/CFS from those in the comparison groups and detect subgroups of persons with ME/CFS who may have different underlying causes. Enrollment began in 2012 and is planned to continue in multiple stages through 2017. We present the MCAM methods in detail, along with an initial description of the 471 patients with ME/CFS who were enrolled in stage 1.


Assuntos
Síndrome de Fadiga Crônica/diagnóstico , Adolescente , Adulto , Progressão da Doença , Síndrome de Fadiga Crônica/epidemiologia , Síndrome de Fadiga Crônica/patologia , Síndrome de Fadiga Crônica/terapia , Feminino , Humanos , Hidrocortisona/análise , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Projetos de Pesquisa , Estudos Retrospectivos , Saliva/química , Inquéritos e Questionários , Estados Unidos/epidemiologia , Adulto Jovem
3.
Lett Appl Microbiol ; 64(2): 124-130, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27981588

RESUMO

A simplified method to produce specific polyclonal rabbit antibodies against sterigmatocystin (STC) was established, using a STC-glycolic acid-ether derivative (STC-GE) conjugated to keyhole limpet haemocyanin (immunogen). The competitive direct enzyme immunoassay (EIA) established for STC had a detection limit (20% binding inhibition) of 130 pg ml-1 . The test was highly specific for STC, with minor cross-reactivity with O-methylsterigmatocystin (OMSTC, 0·87%) and negligible reactivity with aflatoxins (<0·02%). STC-EIA was used in combination with a previously developed specific EIA for aflatoxins (<0·1% cross-reactivity with STC and OMSTC), to study the STC/aflatoxin production profiles of reference strains of Aspergillus species. This immunochemotaxonomic procedure was found to be a convenient tool to identify STC- or aflatoxin-producing strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The carcinogenic mycotoxin sterigmatocystin (STC) is produced by several Aspergillus species, either alone or together with aflatoxins. Here, we report a very simple and straightforward procedure to obtain highly sensitive and specific anti-STC antibodies, and their use in the first ever real STC-specific competitive direct enzyme immunoassay (EIA). In combination with a previous EIA for aflatoxins, this study for the first time demonstrates the potential of a STC/aflatoxin EIA pair for what is branded as 'immunochemotaxonomic' identification of mycotoxigenic Aspergillus species. This new analytical tool enhances analytical possibilities for differential analysis of STC and aflatoxins.


Assuntos
Aflatoxinas/análise , Aspergillus/isolamento & purificação , Técnicas Imunoenzimáticas , Esterigmatocistina/análogos & derivados , Aflatoxinas/biossíntese , Aflatoxinas/imunologia , Anticorpos/imunologia , Aspergillus/classificação , Aspergillus/metabolismo , Reações Cruzadas/imunologia , Sensibilidade e Especificidade , Esterigmatocistina/análise , Esterigmatocistina/imunologia , Esterigmatocistina/metabolismo
4.
J Clin Med ; 13(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38592199

RESUMO

Background: One of the goals of the Multi-site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM) study was to evaluate whether clinicians experienced in diagnosing and caring for patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) recognized the same clinical entity. Methods: We enrolled participants from seven specialty clinics in the United States. We used baseline data (n = 465) on standardized questions measuring general clinical characteristics, functional impairment, post-exertional malaise, fatigue, sleep, neurocognitive/autonomic symptoms, pain, and other symptoms to evaluate whether patient characteristics differed by clinic. Results: We found few statistically significant and no clinically significant differences between clinics in their patients' standardized measures of ME/CFS symptoms and function. Strikingly, patients in each clinic sample and overall showed a wide distribution in all scores and measures. Conclusions: Illness heterogeneity may be an inherent feature of ME/CFS. Presenting research data in scatter plots or histograms will help clarify the challenge. Relying on case-control study designs without subgrouping or stratification of ME/CFS illness characteristics may limit the reproducibility of research findings and could obscure underlying mechanisms.

5.
Diabetes Obes Metab ; 15(1): 77-83, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22882249

RESUMO

AIMS: Regular human insulin (RHI) at high doses shows prolongation of its duration of action potentially leading to late postprandial hypoglycaemia. This study compared late metabolic activity (4-12 and 6-12 h post-dosing) and duration of action (time to reach late half-maximal activity) over a range of doses between insulin aspart (IAsp) and RHI. METHODS: Pharmacokinetic and pharmacodynamic properties of subcutaneous IAsp and RHI (6, 12 and 24 (I)U) were compared in 16 healthy subjects in this double-blind, randomized, six-way crossover glucose clamp study. RESULTS: With increasing doses of both insulins, metabolic activity, insulin exposure, maximum metabolic effect and maximum serum insulin concentration increased linearly. Late metabolic activity was lower for IAsp than RHI at all doses, reaching statistical significance (p < 0.05) for 12 and 24 (I)U. Likewise, IAsp had a shorter duration of action at all doses (p < 0.01) and reached time to 80% of total metabolic activity earlier at doses of 12 and 24 (I)U (p < 0.05). IAsp, compared with RHI, showed a higher maximum metabolic effect at 12 and 24 (I)U (p < 0.0001) and a stronger early metabolic activity for all three doses (p < 0.05). CONCLUSIONS: IAsp showed a shorter duration of action and, particularly with doses of 12 and 24 (I)U, less late metabolic activity than RHI. These properties might contribute to the lower incidence of hypoglycaemia observed with IAsp versus RHI in clinical trials as lower late metabolic activity should decrease the risk of late postprandial hypoglycaemia.


Assuntos
Glicemia/metabolismo , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Insulina Aspart/administração & dosagem , Insulina Aspart/farmacocinética , Insulina/administração & dosagem , Insulina/farmacocinética , Adolescente , Adulto , Área Sob a Curva , Glicemia/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Feminino , Técnica Clamp de Glucose/métodos , Humanos , Hipoglicemiantes/sangue , Insulina/sangue , Insulina Aspart/sangue , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Fatores de Tempo
6.
Artigo em Alemão | MEDLINE | ID: mdl-22116480

RESUMO

Several different systems are used to classify sleep disorders. The International Classification of Sleep Disorders (ICSD-2), established in 2005 by the American Academy of Sleep Medicine (AASM), utilizes eight different categories [1]: insomnias, sleep-related breathing disorders, hypersomnias, circadian rhythm disorders, parasomnias, sleep-related movement disorders, isolated symptoms/normal variants/unresolved issues, as well as other sleep disorders. Sleep disorders are a frequent problem during infancy and childhood, and at least 20% of children in elementary school describe having sleep problems, which are often accompanied by abnormal behavior, hyperactivity, and lack of concentration and result in problems at school. Several sleep disorders, for example, obstructive sleep apnea, have been observed to cause physical diseases as well as growth and developmental problems [2, 3]. Thus, it is essential to detect the problem early, to obtain a differentiated diagnosis, and initiate appropriate therapeutic measures.


Assuntos
Polissonografia/métodos , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/terapia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Transtornos do Sono-Vigília/classificação
7.
J Small Anim Pract ; 61(1): 42-45, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31313312

RESUMO

OBJECTIVES: To evaluate matrix-assisted laser desorption ionisation time of flight mass spectrometry (MALDI-TOF MS) combined with the Sepsityper kit (Bruker Daltoniks GmbH, Bremen) for the direct detection of bacterial species from inoculated blood cultures from dogs and cats. MATERIALS AND METHODS: Canine and feline blood samples were inoculated with typical sepsis-causing bacteria such as Staphylococcus intermedius, Staphylococcus aureus, Streptococcus canis, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa at two distinct concentrations (each in triplicate), resulting in 72 blood culture bottles incubated at 37°C. Samples were comparatively analysed with MALDI-TOF MS after preparation with the Sepsityper kit and also by standard bacteriology (culturing and biochemical characterisation). RESULTS: Bacterial species identified from agar plates and by MALDI-TOF MS from blood culture bottles were identical for all samples. The MALDI Biotyper software (Bruker Daltoniks) correctly identified all bacterial strains from inoculated canine and feline blood with analysis indicating very good precision. CLINICAL SIGNIFICANCE: MALDI-TOF MS analysis combined with the Sepsityper kit is a reliable tool for a quick detection of veterinary-relevant bacterial species directly from blood culture bottles. This approach could reduce the time for identification of critical species to only 24 hours.


Assuntos
Doenças do Gato , Doenças do Cão , Sepse/veterinária , Aceleração , Animais , Bactérias , Técnicas Bacteriológicas/veterinária , Gatos , Cães , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Streptococcus
8.
J Clin Invest ; 130(3): 1491-1505, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31830003

RESUMO

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex disease with no known cause or mechanism. There is an increasing appreciation for the role of immune and metabolic dysfunction in the disease. ME/CFS has historically presented in outbreaks, often has a flu-like onset, and results in inflammatory symptoms. Patients suffer from severe fatigue and postexertional malaise. There is little known about the metabolism of specific immune cells in patients with ME/CFS. To investigate immune metabolism in ME/CFS, we isolated CD4+ and CD8+ T cells from 53 patients with ME/CFS and 45 healthy controls. We analyzed glycolysis and mitochondrial respiration in resting and activated T cells, along with markers related to cellular metabolism and plasma cytokines. We found that ME/CFS CD8+ T cells had reduced mitochondrial membrane potential compared with those from healthy controls. Both CD4+ and CD8+ T cells from patients with ME/CFS had reduced glycolysis at rest, whereas CD8+ T cells also had reduced glycolysis following activation. Patients with ME/CFS had significant correlations between measures of T cell metabolism and plasma cytokine abundance that differed from correlations seen in healthy control subjects. Our data indicate that patients have impaired T cell metabolism consistent with ongoing immune alterations in ME/CFS that may illuminate the mechanism behind this disease.


Assuntos
Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Citocinas , Síndrome de Fadiga Crônica , Mitocôndrias , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Citocinas/sangue , Citocinas/imunologia , Síndrome de Fadiga Crônica/sangue , Síndrome de Fadiga Crônica/imunologia , Síndrome de Fadiga Crônica/patologia , Feminino , Glicólise/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Consumo de Oxigênio/imunologia
9.
J Clin Invest ; 57(4): 1104-7, 1976 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-947953

RESUMO

The renal responses to sympathetic nerve stimulation were studied in saline-expanded rats. The left kidney was partially denervated by crushing the left greater splanchnic nerve. Then the distal portion of the nerve was stimulated with square wave pulses of 0.5 ms duration, voltage twice threshold, and 1 or 2 Hz frequency while monitoring the compound action potential. Fibers with conduction speeds of 13-17 m-s-1 and of 0.7-1 m-s-1 were identified. Only stimulation of the latter appeared to produce changes in renal Na and water excretion. Whole kidney and individual nephron studies were performed alternating control and nerve stimulation periods. Nerve stimulation produced approximately a 25% reduction of the left kidney urine volume and sodium excretion. Glomerular filtration rate and renal plasma flow remained unchanged. Right kidney Na and water excretion, glomerular filtration rate, and renal plasma flow remained constant. In the left kidney, during nerve stimulation, the tubular fluid to plasma inulin concentration ratio increased significantly in the late proximal tubule. We conclude that the antidiuresis and antinatriuresis seen during sympathetic nerve stimulation were caused by increased sodium and water reabsorption in the proximal tubule, probably mediated by the stimulation of slowly conducting unmyelinated fibers. These responses appeared to be unrelated to systemic or intrarenal hemodynamic changes.


Assuntos
Túbulos Renais Proximais/metabolismo , Rim/inervação , Sódio/metabolismo , Sistema Nervoso Simpático , Água/metabolismo , Absorção , Animais , Denervação , Estimulação Elétrica , Taxa de Filtração Glomerular , Rim/fisiologia , Masculino , Punções , Ratos , Fluxo Sanguíneo Regional
10.
J Clin Invest ; 53(5): 1402-23, 1974 May.
Artigo em Inglês | MEDLINE | ID: mdl-4825232

RESUMO

Micropuncture, clearance, immunofluorescence and light microscopy techniques were used to study kidney structure and single nephron function in rats with autologous immune complex nephritis (AICN), a membranous glomerulonephritis developing over 5 to 20 mo, in the more acute and proliferative glomerular basement membrane (GBM) nephritis and in controls. Both models are known to have clinical counterparts in human disease. Kidney functional abnormalities correlated with the degree of architectural derangement. In both AICN and anti-GBM nephritis filtration fraction fell in direct proportion to the fall in glomerular filtration rate (GFR), renal plasma flow being unchanged. Fractional electrolyte excretion increased as the GFR fell. Despite marked heterogeneity of single nephron filtration rate (SNGFR) (AICN, 5-93 nl/min; anti-GBM, 0-50 nl/min) and of proximal tubular hydrostatic pressure (4-48 mm Hg), each nephron showed almost complete glomerulotubular balance, absolute reabsorption to the late proximal convolution varying directly with filtration rate. In addition SNGFR could be related both to proximal intratubular hydrostatic pressure and to calculated glomerular capillary pressure (Pg), being lowest in those nephrons with the highest intratubular pressure. Nephrons with very high filtration rates did not apparently reach filtration equilibrium. Mean SNGFR was significantly lower in the anti-GBM group, while calculated Pg was the same in both. This probably reflects the acute and diffuse involvement of the anti-GBM lesion with different filtration characteristics from the more chronic AICN disease. Tubular damage was more marked in AICN, and extraction of p-aminohippurate was reduced in this group.


Assuntos
Glomerulonefrite/fisiopatologia , Rim/fisiopatologia , Proteínas Sanguíneas/análise , Nitrogênio da Ureia Sanguínea , Radioisótopos de Carbono , Colesterol/sangue , Taxa de Filtração Glomerular , Glomerulonefrite/sangue , Pressão Hidrostática , Rim/irrigação sanguínea , Rim/patologia , Túbulos Renais Proximais/fisiopatologia , Néfrons/patologia , Néfrons/fisiopatologia , Proteinúria , Trítio , Equilíbrio Hidroeletrolítico
11.
J Clin Invest ; 53(5): 1497-500, 1974 May.
Artigo em Inglês | MEDLINE | ID: mdl-4825239

RESUMO

Complete ureteral ligation of 24-h duration significantly reduced stop-flow and estimated glomerular capillary pressures in nephrons accessible to micropuncture in obstructed kidneys. In kidneys without ureteral obstruction, a similar response occurred in single tubules blocked for 24 h without affecting nearby unblocked tubules. Thus, the response to tubular obstruction occurs on an individual nephron basis and results from constriction of individual afferent arterioles. The mechanism leading to the response is unknown, but a feedback mechanism operating through the juxtaglomerular apparatus of individual nephrons is an attractive possibility.


Assuntos
Rim/fisiologia , Animais , Retroalimentação , Ligadura , Masculino , Néfrons/fisiologia , Ratos , Ureter/fisiologia
12.
J Clin Invest ; 51(3): 484-92, 1972 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-5011096

RESUMO

Renal tubular permeability was studied by microinjection techniques during increased intrarenal pressure in anesthetized diuretic rats. Intrarenal pressure, as evidenced by intratubular pressure (ITP), was increased by elevation of ureteral pressure, partial renal venous constriction, or massive saline diuresis. Various combinations of radioactive inulin, creatinine, mannitol, sucrose, and iothalamate in isotonic saline were microinjected into superficial proximal and distal convolutions, and recovery of the isotopes was measured in the urine. Inulin was completely recovered in the urine from the injected kidney at both normal and elevated ITP. Creatinine, mannitol, sucrose, and iothalamate were also completely recovered at normal ITP, but recoveries were significantly lower, averaging 73, 85, 89, and 85%, respectively, after early proximal injection when proximal ITP was increased to 30+/-2 mm Hg by elevation of ureteral pressure. Since transit time is prolonged under these conditions, mannitol recovery was also studied during aortic constriction, which prolongs transit time but lowers ITP. Recovery was complete. A significant loss of mannitol was observed during massive saline diuresis, which shortens transit time but increases ITP. During renal venous constriction producing a proximal ITP of 30+/-2 mm Hg, mannitol recovery was significantly less than 100% even after microinjection into distal convolutions, but the loss was greater injection at more proximal puncture sites. Mannitol recovery was complete during elevation of ureteral pressure in the contralateral kidney. These studies demonstrate a change in the permeability characteristics of all major segments of the renal tubule during elevation of intrarenal pressure. This change is rapidly reversible and does not appear to be due to a humoral factor which gains access to the general circulation.


Assuntos
Permeabilidade da Membrana Celular , Túbulos Renais/fisiologia , Pressão , Animais , Isótopos de Carbono , Constrição , Creatinina , Diurese , Taxa de Filtração Glomerular , Inulina , Isótopos de Iodo , Ácido Iotalâmico , Masculino , Manitol , Métodos , Peso Molecular , Punções , Ratos , Ratos Endogâmicos , Veias Renais/fisiologia , Sacarose , Fatores de Tempo , Trítio , Obstrução Ureteral/fisiopatologia
13.
J Clin Invest ; 50(1): 35-48, 1971 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-5543881

RESUMO

Intrarenal transport of urate-2-(14)C was studied in anesthetized rats using the microinjection technic. During saline diuresis, small volumes of urate-2-(14)C (0.24-0.48 mM) and inulin-(3)H were injected into surface proximal and distal convoluted tubules, and ureteral urine was collected serially. Total (74-96%) and direct (57-84%) urate recovery increased significantly the more distal the puncture site. Delayed recovery (+/-20%) remained approximately the same regardless of localization of the microinjection. After proximal injections, total and direct recoveries of urate-2-(14)C were significantly higher in rats treated with probenecid, pyrazinoate, or PAH than during saline diuresis alone, while the excretion rates were comparable after distal injection. Delayed recovery was not altered by drug administration. The decreased proximal reabsorption of urate is presumably due to an effect of the drugs on the luminal membrane of the nephron. For perfusion at high urate concentrations, nonradioactive urate was added to the injectate (0.89-1.78 mM). Urate-2-(14)C recovery was almost complete and there was no delayed excretion, demonstrating saturation kinetics. These findings are compatible with a carrier-mediated mechanism for urate transport probably located at the luminal border of the proximal tubular epithelium. No definitive evidence for urate secretion was found in these studies.


Assuntos
Transporte Biológico , Ácidos Aminoipúricos/farmacologia , Animais , Isótopos de Carbono , Cromatografia , Diurese/efeitos dos fármacos
14.
J Clin Invest ; 56(1): 208-17, 1975 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1141432

RESUMO

Studies were undertaken to characterize the renal responses to acute unilateral renal denervation and the mechanisms involved in these responses. Denervation was produced in anesthetized nondiuretic rats by application of phenol to the left renal artery. Studies were also performed in sham-denervated nondiuretic rats. Whole kidney and individual nephron studies were performed before and after denervation or sham denervation. Denervation increased urine volume from the left kidney to about twice its control value (P less than 0.001) and increased urinary sodium excretion from 332 neq min minus -1 to 1,887 neq min minus -1 (P less than 0.001). Glomerular filtration rate (GFR) and renal plasma flow (RPF) remained unchanged in both kidneys after the procedure. The innervated right kidney showed no changes in urine volume or in sodium excretion. After denervation, late proximal ratio of tubular fluid inulin concentration to that of plasma [(F/P)In] decreased from 2.23 to 1.50 (P less than 0.001) while single nephron GFR remained unchanged. Absolute reabsorption decreased from 16.5 to 9.9 n. min minus -1 (P less than 0.001). (F/P)In ratios were also decreased in early distal (from 6.21 to 3.18, P less 0.001) and late distal convolutions (from 16.41 to 8.33, P less than 0.001) during the experimental period. (F/P)Na ratios remained unchanged in the early distal convolutions, but increased from 0.18 to 0.38 (P less than 0.01) in late distal convolutions after denervation. Absolute Na reabsorption after denervation increased in the loop of Henle, distal convolution, and collecting ducts. Any changes in intrarenal hydrostatic pressures after denervation were always small. There were no changes in GFR, RPF, urine volume, urinary sodium excretion, or late proximal (F/P)In after sham denervation. We conclude that the diuresis and natriuresis seen after acute renal denervation were caused by a marked depression of sodium and water reabsorption in the proximal tubule with partial compensation in more distal nephron segments. These responses appeared to be unrelated to systemic or intrarenal hemodynamic changes. The results demonstrate an effect of the renal nerves on proximal tubular function.


Assuntos
Rim/inervação , Ácidos Aminoipúricos , Animais , Pressão Sanguínea , Radioisótopos de Carbono , Denervação , Diurese , Taxa de Filtração Glomerular , Inulina , Rim/irrigação sanguínea , Rim/fisiologia , Túbulos Renais Proximais/inervação , Túbulos Renais Proximais/fisiologia , Masculino , Natriurese , Néfrons/inervação , Néfrons/fisiologia , Fenóis/farmacologia , Pressão , Ratos , Fluxo Sanguíneo Regional , Artéria Renal/efeitos dos fármacos , Trítio , Equilíbrio Hidroeletrolítico
15.
Transl Psychiatry ; 7(4): e1080, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28375204

RESUMO

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a persistent and debilitating disorder marked by cognitive and sensory dysfunction and unexplained physical fatigue. Classically, cases present after a prodrome consistent with infection; however, some cases are atypical and have a different presentation and comorbidities that pose challenges for differential diagnosis. We analyzed cerebrospinal fluid (CSF) from 32 cases with classical ME/CFS and 27 cases with atypical ME/CFS using a 51-plex cytokine assay. Atypical subjects differed in cytokine profiles from classical subjects. In logistic regression models incorporating immune molecules that were identified as potential predictor variables through feature selection, we found strong associations between the atypical ME/CFS phenotype and lower CSF levels of the inflammatory mediators, interleukin 17A and CXCL9. Network analysis revealed an absence of inverse inter-cytokine relationships in CSF from atypical patients, and more sparse positive intercorrelations, than classical subjects. Interleukin 1 receptor antagonist appeared to be a negative regulator in classical ME/CFS, with patterns suggestive of disturbances in interleukin 1 signaling and autoimmunity-type patterns of immune activation. Immune signatures in the central nervous system of ME/CFS patients with atypical features may be distinct from those with more typical clinical presentations.


Assuntos
Líquido Cefalorraquidiano/imunologia , Citocinas/líquido cefalorraquidiano , Síndrome de Fadiga Crônica/líquido cefalorraquidiano , Síndrome de Fadiga Crônica/imunologia , Adulto , Quimiocina CXCL9/líquido cefalorraquidiano , Quimiocina CXCL9/imunologia , Citocinas/imunologia , Diagnóstico Diferencial , Síndrome de Fadiga Crônica/diagnóstico , Feminino , Humanos , Interleucina-17/imunologia , Masculino , Pessoa de Meia-Idade
16.
Int J Hyg Environ Health ; 219(2): 143-65, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26725999

RESUMO

Mycotoxins are toxic secondary metabolites of various fungal species that can contaminate food and feed, as well as indoor environments. Numerous studies have summarized the adverse health effects of mycotoxins and described severe intoxications of humans and animals. The major health concerns are caused via the alimentary route which unambiguously is the main source for human internal exposure; however, the relevance of other pathways under environmental and occupational conditions should also be considered. Thus firstly, this review aims in summarizing literature data on potentially inhalable mycotoxins occurring in dusts or air in residences and in working environments. Secondly, it gives an overview of the overall internal body burden of mycotoxins in humans in an attempt to characterize total human exposure. These data are also discussed in relation to the current toxicologically based values used for risk assessment.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/análise , Micotoxinas/análise , Poluição do Ar em Ambientes Fechados/análise , Animais , Carga Corporal (Radioterapia) , Poeira/análise , Habitação , Humanos , Leite Humano/química , Medição de Risco , Local de Trabalho
17.
Sci Adv ; 1(1)2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26079000

RESUMO

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is an unexplained incapacitating illness that may affect up to 4 million people in the United States alone. There are no validated laboratory tests for diagnosis or management despite global efforts to find biomarkers of disease. We considered the possibility that inability to identify such biomarkers reflected variations in diagnostic criteria and laboratory methods as well as the timing of sample collection during the course of the illness. Accordingly, we leveraged two large, multicenter cohort studies of ME/CFS to assess the relationship of immune signatures with diagnosis, illness duration, and other clinical variables. Controls were frequency-matched on key variables known to affect immune status, including season of sampling and geographic site, in addition to age and sex. We report here distinct alterations in plasma immune signatures early in the course of ME/CFS (n = 52) relative to healthy controls (n = 348) that are not present in subjects with longer duration of illness (n = 246). Analyses based on disease duration revealed that early ME/CFS cases had a prominent activation of both pro- and anti-inflammatory cytokines as well as dissociation of intercytokine regulatory networks. We found a stronger correlation of cytokine alterations with illness duration than with measures of illness severity, suggesting that the immunopathology of ME/CFS is not static. These findings have critical implications for discovery of interventional strategies and early diagnosis of ME/CFS.

18.
Am J Psychiatry ; 158(3): 486-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11229995

RESUMO

OBJECTIVE: Deficits in dopaminergic function may contribute to hypertrophy of striatal structures associated with typical neuroleptic treatment. In light of a body of research that has associated chronic cocaine use with extrapyramidal symptoms and striatal dopaminergic depletion, the authors looked for evidence of striatal dysmorphology in patients with chronic cocaine dependence. METHOD: Caudate, putamen, and total brain volumes were quantified by means of magnetic resonance imaging in 25 cocaine-dependent and 20 healthy subjects. RESULTS: Normalized caudate and putamen volumes were 3.40% and 9.18% larger, respectively, in the cocaine-dependent subjects. CONCLUSIONS: These observations suggest that deficits in dopaminergic function associated with cocaine dependence may contribute to striatal hypertrophy.


Assuntos
Núcleo Caudado/anatomia & histologia , Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Putamen/anatomia & histologia , Adulto , Encéfalo/anatomia & histologia , Transtornos Relacionados ao Uso de Cocaína/patologia , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Corpo Estriado/patologia , Dopamina/fisiologia , Feminino , Humanos , Hipertrofia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade
19.
Am J Psychiatry ; 158(1): 86-95, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11136638

RESUMO

OBJECTIVE: Identification of brain activity associated with craving is important for understanding the neurobiology of addiction. METHOD: Brain activity was measured in cocaine addicts and healthy subjects by functional magnetic resonance imaging (fMRI) while the subjects watched videotapes designed to elicit happy feelings, sad feelings, or the desire to use cocaine. The subjects indicated the onset of drug craving or emotional response, allowing comparison of groups before and after such feelings. RESULTS: Robust activation of the anterior cingulate was evident in patients watching cocaine-cue tapes but not in patients watching happy or sad tapes or in healthy subjects under any condition. Anterior cingulate activation preceded the reported onset of craving and was evident in patients who did not report craving. In contrast, patients showed less activation than healthy subjects during the cocaine-cue tapes in areas of the frontal lobes. After the reported onset of craving, cocaine-dependent subjects showed greater activity than healthy subjects in regions that are more active in healthy subjects when they watch sad tapes than when they watch happy tapes, suggesting a physiologic link between cocaine-cue responses and normal dysphoric states. Dynamic aspects of regional brain activations, but not the location of activations, were abnormal in cocaine-dependent subjects watching sad tapes, suggesting more general affective dysregulation. Patients showed low activation of sensory areas during initial viewing of all videotapes, suggesting generalized alteration in neuroresponsiveness. CONCLUSIONS: Cocaine cues lead to abnormally high cingulate and low frontal lobe activation in cocaine addicts. Addicts also show more general abnormalities in affect-related brain activation.


Assuntos
Comportamento Aditivo/diagnóstico , Encéfalo/fisiologia , Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Imageamento por Ressonância Magnética/estatística & dados numéricos , Adulto , Afeto/fisiologia , Comportamento Aditivo/psicologia , Encéfalo/metabolismo , Transtornos Relacionados ao Uso de Cocaína/psicologia , Sinais (Psicologia) , Emoções/fisiologia , Feminino , Lobo Frontal/fisiologia , Giro do Cíngulo/fisiologia , Felicidade , Humanos , Masculino , Pessoa de Meia-Idade , Gravação de Videoteipe , Percepção Visual/fisiologia
20.
Drug Alcohol Depend ; 62(1): 49-56, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11173167

RESUMO

Preclinical and clinical studies have shown that cocaine increases plasma adrenocorticotropin hormone (ACTH) and cortisol. Chronic elevation of plasma cortisol exerts direct toxic effects upon hippocampal neurons and exacerbates hippocampal damage resulting from ischemia and seizures. The authors tested for evidence of hippocampal damage in patients with chronic cocaine dependence. Medial temporal lobe and total brain volumes were quantified using magnetic resonance imaging (MRI) in 27 patients with cocaine dependence and 16 healthy subjects. Basal and ovine corticotropin releasing hormone (oCRH) stimulated ACTH and cortisol levels were also examined in a subset of 8 healthy and 9 cocaine dependent subjects after 21 days of abstinence. No evidence for decreased hippocampal or total brain volume in cocaine dependence was observed. Similarly, basal and oCRH stimulated ACTH and cortisol levels in cocaine dependent patients did not differ from those in healthy subjects.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/patologia , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Lobo Temporal/patologia , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/efeitos dos fármacos , Adulto , Análise de Variância , Área Sob a Curva , Transtornos Relacionados ao Uso de Cocaína/sangue , Hormônio Liberador da Corticotropina/farmacologia , Feminino , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Análise de Regressão , Lobo Temporal/efeitos dos fármacos , Lobo Temporal/fisiologia
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