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1.
Adv Tech Stand Neurosurg ; 46: 1-21, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37318567

RESUMO

In 2021 the World Health Organization issued the fifth edition of its classification of the tumors of the central nervous system. This revision made many significant changes in the overall structure of the tumor taxonomy, as well as utilizing to a greatly increased reliance on molecular genetic data to specify the various diagnoses described in the classification, and to add some new tumor types. This represents a trend following the pioneering introduction of certain required genetic alterations for particular diagnoses encoded in the 2016 revision of the preceding fourth edition. In this chapter I describe the major changes and comment on their significance, and highlight some areas which are, at least to me, controversial. The major tumor categories discussed include gliomas, ependymomas, and embryonal tumors, but all tumor types included in the classification are addressed to the extent necessary.


Assuntos
Neoplasias Encefálicas , Neoplasias do Sistema Nervoso Central , Ependimoma , Glioma , Humanos , Neoplasias do Sistema Nervoso Central/diagnóstico , Sistema Nervoso Central/patologia , Glioma/diagnóstico , Organização Mundial da Saúde
2.
J Ultrasound Med ; 42(8): 1689-1698, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36723246

RESUMO

OBJECTIVES: Lung ultrasound (LUS) is a powerful and accessible clinical tool for pulmonary diagnosis, but risk of pulmonary capillary hemorrhage (PCH) presents a safety issue. The dependence of PCH in a rat model of LUS was evaluated for image frames-per-second (fps) and associated on-screen Mechanical Index (MIOS ) and Thermal Index (TI). METHODS: A Philips iE33 machine with L15-7io probe was used to scan anesthetized rats in a warmed water bath. B mode was applied at 9 MHz with settings of 34, 61 and 118 fps. After 2 minutes of exposure at an MIOS setting, samples were obtained for assessment of PCH areas on the lung surface. Ultrasound parameters were measured to determine the in situ MIIS at the lung surface. RESULTS: The PCH trend counter-intuitively decreased with increasing fps, with areas of 19.5 mm2 for 34 fps (MIOS  = 1.0, TI = 0.8, 4080 images), 9.6 mm2 at 61 fps (MIOS  = 1.0, TI = 0.5, 7320 images) and 7.5 mm2 at 118 fps (MIOS  = 1.1, TI = 0.4, 14,160 images). The PCH was not significantly different for 34 fps (TI = 0.5, MIOS  = 0.8) (10.7 mm2 ), compared to 61 and 118 fps, above, indicating some value for the TI as a predictive indicator of PCH. MIIS thresholds were 0.42, 0.46, and 0.49 for 34, 61 and 118 fps, respectively. CONCLUSIONS: The increase in PCH at low fps was associated with delivering more relatively high amplitude grazing pulse exposures during slower image scans. No significant PCH was found for the MIOS setting of 0.5, corresponding to in MIIS values of 0.35-0.39.


Assuntos
Pneumopatias , Ratos , Animais , Ratos Sprague-Dawley , Modelos Animais de Doenças , Pneumopatias/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pulmão/irrigação sanguínea , Hemorragia/diagnóstico por imagem
3.
J Ultrasound Med ; 42(2): 309-344, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35993596

RESUMO

Following the innovations and new discoveries of the last 10 years in the field of lung ultrasound (LUS), a multidisciplinary panel of international LUS experts from six countries and from different fields (clinical and technical) reviewed and updated the original international consensus for point-of-care LUS, dated 2012. As a result, a total of 20 statements have been produced. Each statement is complemented by guidelines and future developments proposals. The statements are furthermore classified based on their nature as technical (5), clinical (11), educational (3), and safety (1) statements.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Consenso , Pulmão/diagnóstico por imagem , Testes Imediatos , Ultrassonografia
4.
Ultraschall Med ; 44(5): 516-519, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36377189

RESUMO

The safety of ultrasound is of particular importance when examining the lungs, due to specific bioeffects occurring at the alveolar air-tissue interface. Lung is significantly more sensitive than solid tissue to mechanical stress. The causal biological effects due to the total reflection of sound waves have also not been investigated comprehensively.On the other hand, the clinical benefit of lung ultrasound is outstanding. It has gained considerable importance during the pandemic, showing comparable diagnostic value with other radiological imaging modalities.Therefore, based on currently available literature, this work aims to determine possible effects caused by ultrasound on the lung parenchyma and evaluate existing recommendations for acoustic output power limits when performing lung sonography.This work recommends a stepwise approach to obtain clinically relevant images while ensuring lung ultrasound safety. A special focus was set on the safety of new ultrasound modalities, which had not yet been introduced at the time of previous recommendations.Finally, necessary research and training steps are recommended in order to close knowledge gaps in the field of lung ultrasound safety in the future.These recommendations for practice were prepared by ECMUS, the safety committee of the EFSUMB, with participation of international experts in the field of lung sonography and ultrasound bioeffects.

5.
J Neurosci ; 41(25): 5453-5470, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-33980544

RESUMO

Dopaminergic neurons of the substantia nigra pars compacta (SNC) and ventral tegmental area (VTA) exhibit spontaneous firing activity. The dopaminergic neurons in these regions have been shown to exhibit differential sensitivity to neuronal loss and psychostimulants targeting dopamine transporter. However, it remains unclear whether these regional differences scale beyond individual neuronal activity to regional neuronal networks. Here, we used live-cell calcium imaging to show that network connectivity greatly differs between SNC and VTA regions with higher incidence of hub-like neurons in the VTA. Specifically, the frequency of hub-like neurons was significantly lower in SNC than in the adjacent VTA, consistent with the interpretation of a lower network resilience to SNC neuronal loss. We tested this hypothesis, in DAT-cre/loxP-GCaMP6f mice of either sex, when activity of an individual dopaminergic neuron is suppressed, through whole-cell patch clamp electrophysiology, in either SNC or VTA networks. Neuronal loss in the SNC increased network clustering, whereas the larger number of hub-neurons in the VTA overcompensated by decreasing network clustering in the VTA. We further show that network properties are regulatable via a dopamine transporter but not a D2 receptor dependent mechanism. Our results demonstrate novel regulatory mechanisms of functional network topology in dopaminergic brain regions.SIGNIFICANCE STATEMENT In this work, we begin to untangle the differences in complex network properties between the substantia nigra pars compacta (SNC) and VTA, that may underlie differential sensitivity between regions. The methods and analysis employed provide a springboard for investigations of network topology in multiple deep brain structures and disorders.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neurônios Dopaminérgicos/fisiologia , Rede Nervosa/fisiologia , Parte Compacta da Substância Negra/fisiologia , Área Tegmentar Ventral/fisiologia , Animais , Feminino , Masculino , Camundongos
6.
J Neurosci ; 40(30): 5871-5891, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32576620

RESUMO

Manganese exposure produces Parkinson's-like neurologic symptoms, suggesting a selective dysregulation of dopamine transmission. It is unknown, however, how manganese accumulates in dopaminergic brain regions or how it regulates the activity of dopamine neurons. Our in vivo studies in male C57BLJ mice suggest that manganese accumulates in dopamine neurons of the VTA and substantia nigra via nifedipine-sensitive Ca2+ channels. Manganese produces a Ca2+ channel-mediated current, which increases neurotransmitter release and rhythmic firing activity of dopamine neurons. These increases are prevented by blockade of Ca2+ channels and depend on downstream recruitment of Ca2+-activated potassium channels to the plasma membrane. These findings demonstrate the mechanism of manganese-induced dysfunction of dopamine neurons, and reveal a potential therapeutic target to attenuate manganese-induced impairment of dopamine transmission.SIGNIFICANCE STATEMENT Manganese is a trace element critical to many physiological processes. Overexposure to manganese is an environmental risk factor for neurologic disorders, such as a Parkinson's disease-like syndrome known as manganism. We found that manganese concentration-dependently increased the excitability of dopamine neurons, decreased the amplitude of action potentials, and narrowed action potential width. Blockade of Ca2+ channels prevented these effects as well as manganese accumulation in the mouse midbrain in vivo Our data provide a potential mechanism for manganese regulation of dopaminergic neurons.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Manganês/metabolismo , Manganês/toxicidade , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos
7.
J Pharmacol Exp Ther ; 379(3): 372-385, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34535563

RESUMO

Methamphetamine (METH) is a potent psychostimulant that increases extracellular monoamines, such as dopamine and norepinephrine, and affects multiple tissue and cell types in the central nervous system (CNS) and peripheral immune cells. The reinforcing properties of METH underlie its significant abuse potential and dysregulation of peripheral immunity and central nervous system functions. Together, the constellation of METH's effects on cellular targets and regulatory processes has led to immune suppression and neurodegeneration in METH addicts and animal models of METH exposure. Here we extensively review many of the cell types and mechanisms of METH-induced dysregulation of the central nervous and peripheral immune systems. SIGNIFICANCE STATEMENT: Emerging research has begun to show that methamphetamine regulates dopaminergic neuronal activity. In addition, METH affects non-neuronal brain cells, such as microglia and astrocytes, and immunological cells of the periphery. Concurrent disruption of bidirectional communication between dopaminergic neurons and glia in the CNS and peripheral immune cell dysregulation gives rise to a constellation of dysfunctional neuronal, cell, and tissue types. Therefore, understanding the pathophysiology of METH requires consideration of the multiple targets at the interface between basic and clinical neuroscience.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Estimulantes do Sistema Nervoso Central/farmacologia , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Metanfetamina/farmacologia , Animais , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/imunologia , Humanos , Microglia/efeitos dos fármacos , Microglia/imunologia
8.
Oncology (Williston Park) ; 35(11): 733-740, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-35088971

RESUMO

Glioblastoma (GBM), the most common primary brain tumor, is a highly aggressive malignancy for which the median survival is about 13 months, and 5-year survival is well under 5%. These tumors usually occur in the brain and enlarge and infiltrate through white matter, including crossing through the corpus callosum to the opposite cerebral hemisphere. They may spread to distant parts of the central nervous system (CNS) via cerebrospinal fluid pathways. Extraneural metastases from primary brain tumors are quite rare, for 2 probable reasons: because most patients survive less than 2 years, and because of the absence of true lymphatics in the CNS. Typical sites for distant extraneural metastasis of GBM are lungs and pleura, followed by lymph nodes and bones; spread to the liver is exceptional. Most of the reported cases with liver metastases had either single or only a few such metastatic lesions. We report a probably unique case of GBM with extensive liver metastases along with a review of previous cases of liver metastasis from GBM, and we discuss the possible mechanisms of metastasis.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Glioblastoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Neoplasias Encefálicas/terapia , Glioblastoma/secundário , Glioblastoma/terapia , Humanos , Neoplasias Hepáticas/terapia
9.
J Ultrasound Med ; 40(4): 787-794, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32856724

RESUMO

OBJECTIVES: Lung ultrasound (LUS) exposure can induce pulmonary capillary hemorrhage (PCH), depending on biological and physical exposure parameters. This study was designed to investigate the variation in the LUS induction of PCH due to hemorrhagic shock, which itself can engender pulmonary injury. METHODS: Male rats were anesthetized with isoflurane in air. Shock was induced by withdrawal of 40% of the blood volume and assessed by the blood pressure detected by a femoral artery catheter and by blood glucose tests. B-mode ultrasound was delivered at 7.3 MHz with a low output (-20 dB) for aiming and with the maximal output (0 dB) for exposure. Pulmonary capillary hemorrhage was quantified by an assessment of comet tail artifacts in the LUS images and by measurement of PCH areas on the surface of fresh lung samples. RESULTS: Tests without shock or catheterization surgery gave results for PCH similar to those of previous studies using different methods. Exposure before hemorrhagic shock gave a mean PCH area ± SE of 24.8 ± 9.2 mm2 on the ultrasound scan plane, whereas exposure after shock gave 0 PCH (P < .001; n = 7). CONCLUSIONS: The presence of hemorrhagic shock significantly reduces the occurrence of LUS-induced PCH.


Assuntos
Choque Hemorrágico , Animais , Modelos Animais de Doenças , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Pulmão/diagnóstico por imagem , Masculino , Ratos , Ratos Sprague-Dawley , Choque Hemorrágico/diagnóstico por imagem
10.
Mol Pharmacol ; 98(6): 695-709, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33020143

RESUMO

The currents of α7 nicotinic acetylcholine receptors activated by acetylcholine (ACh) are brief. The channel has high permeability to calcium relative to monovalent cations and shows inward rectification. It has been previously noted that in the presence of positive allosteric modulators (PAMs), currents through the channels of α7 receptors differ from normal α7 currents both in sensitivity to specific channel blockers and their current-voltage (I-V) relationships, no longer showing inward rectification. Linear I-V functions are often associated with channels lacking calcium permeability, so we measured the I-V functions of α7 receptors activated by ACh when PAMs were bound to the allosteric binding site in the transmembrane domain. Currents were recorded in chloride-free Ringer's solution with low or high concentrations of extracellular calcium to determine the magnitude of the reversal potential shift in the two conditions as well as the I-V relationships. ACh-evoked currents potentiated by the allosteric agonist-PAMs (ago-PAMs) (3aR,4S,9bS)-4-(4-bromophenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-sulfonamide (GAT107) and 3-(3,4-difluorophenyl)-N-(1-(6-(4-(pyridin-2-yl)piperazin-1-yl)pyrazin-2-yl)ethyl)propenamide (B-973B) showed reduced inward rectification and calcium-dependent reversal potential shifts decreased by 80%, and 50%, respectively, compared with currents activated by ACh alone, indicative of reduced calcium permeability. Currents potentiated by 3a,4,5,9b-tetrahydro-4-(1-naphthalenyl)-3H-cyclopentan[c]quinoline-8-sulfonamide were also linear and showed no calcium-dependent reversal potential shifts. The ago-PAMs GAT-107 and B-973B stimulated increases in intracellular calcium in stably transfected HEK293 cells. However, these calcium signals were delayed relative to channel activation produced by these agents and were insensitive to the channel blocker mecamylamine. Our results indicate that, although allosterically activated α7 nicotinic ACh receptor may affect intracellular calcium levels, such effects are not likely due to large channel-dependent calcium influx. SIGNIFICANCE STATEMENT: Positive allosteric modulators (PAMs) of α7 nicotinic acetylcholine receptor can increase channel activation by two or more orders of magnitude, raising the concern that, due to the relatively high calcium permeability of α7 receptors activated by acetylcholine alone, such efficacious PAMs may have cytotoxic side effects. We show that PAMs alter the ion conduction pathway and, in general, reduce the calcium permeability of the channels. This supports the hypothesis that α7 effects on intracellular calcium may be independent of channel-mediated calcium influx.


Assuntos
Cálcio/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Acetilcolina/metabolismo , Regulação Alostérica/efeitos dos fármacos , Sítio Alostérico , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Células HEK293 , Humanos , Oócitos , Técnicas de Patch-Clamp , Fenilpropionatos/farmacologia , Piperazinas/farmacologia , Quinolinas/farmacologia , Sulfonamidas/farmacologia , Xenopus laevis , Receptor Nicotínico de Acetilcolina alfa7/agonistas
11.
Glia ; 68(11): 2228-2245, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32275335

RESUMO

During aging humans lose midbrain dopamine neurons, but not all dopamine regions exhibit vulnerability to neurodegeneration. Microglia maintain tissue homeostasis and neuronal support, but microglia become senescent and likely lose some of their functional abilities. Since aging is the greatest risk factor for Parkinson's disease, we hypothesized that aging-related changes in microglia and neurons occur in the vulnerable substantia nigra pars compacta (SNc) but not the ventral tegmental area (VTA). We conducted stereological analyses to enumerate microglia and dopaminergic neurons in the SNc and VTA of 1-, 6-, 9-, 18-, and 24-month-old C57BL/J6 mice using sections double-stained with tyrosine hydroxylase (TH) and Iba1. Both brain regions show an increase in microglia with aging, whereas numbers of TH+ cells show no significant change after 9 months of age in SNc and 6 months in VTA. Morphometric analyses reveal reduced microglial complexity and projection area while cell body size increases with aging. Contact sites between microglia and dopaminergic neurons in both regions increase with aging, suggesting increased microglial support/surveillance of dopamine neurons. To assess neurotrophin expression in dopaminergic neurons, BDNF and TH mRNA were quantified. Results show that the ratio of BDNF to TH decreases in the SNc, but not the VTA. Gait analysis indicates subtle, aging-dependent changes in gait indices. In conclusion, increases in microglial cell number, ratio of microglia to dopamine neurons, and contact sites suggest that innate biological mechanisms compensate for the aging-dependent decline in microglia morphological complexity (senescence) to ensure continued neuronal support in the SNc and VTA.


Assuntos
Microglia , Substância Negra , Área Tegmentar Ventral , Animais , Fator Neurotrófico Derivado do Encéfalo , Neurônios Dopaminérgicos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
12.
Br J Anaesth ; 124(6): 693-701, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32245569

RESUMO

BACKGROUND: This study assessed whether i.v. sildenafil citrate prevented acute kidney injury in at-risk patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS: In a double-blind RCT, adults at increased risk of acute kidney injury undergoing cardiac surgery in a single UK tertiary centre were randomised to receive sildenafil citrate 12.5 mg kg-1 i.v. over 150 min or dextrose 5% at the commencement of surgery. The primary outcome was serum creatinine measured at six post-randomisation time points. The primary analysis used a linear mixed-effects model adjusted for the stratification variables, baseline estimated glomerular filtration rate, and surgical procedure. Secondary outcomes considered clinical events and potential disease mechanisms. Effect estimates were expressed as mean differences (MDs) or odds ratios with 95% confidence intervals. RESULTS: The analysis population comprised eligible randomised patients that underwent valve surgery or combined coronary artery bypass graft and valve surgery, with cardiopulmonary bypass, between May 2015 and June 2018. There were 60 subjects in the sildenafil group and 69 in the placebo control group. The difference between groups in creatinine concentration was not statistically significant (MD: 0.88 µmol L-1 [-5.82, 7.59]). There was a statistically significant increase in multiple organ dysfunction scores in the sildenafil group (MD: 0.54 [0.02, 1.07]; P=0.044). Secondary outcomes, and biomarkers of kidney injury, endothelial function, and inflammatory cell activation, were not significantly different between the groups. CONCLUSIONS: These results do not support the use of i.v. sildenafil citrate for kidney protection in adult cardiac surgery. CLINICAL TRIAL REGISTRATION: ISRCTN18386427.


Assuntos
Injúria Renal Aguda/prevenção & controle , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Inibidores da Fosfodiesterase 5/uso terapêutico , Complicações Pós-Operatórias/prevenção & controle , Citrato de Sildenafila/uso terapêutico , Administração Intravenosa , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Glucose/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Fosfodiesterase 5/administração & dosagem , Citrato de Sildenafila/administração & dosagem , Reino Unido
13.
J Ultrasound Med ; 39(6): 1069-1084, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31868252

RESUMO

Potential ultrasound exposure safety issues are reviewed, with guidance for prudent use of point-of-care ultrasound (POCUS). Safety assurance begins with the training of POCUS practitioners in the generation and interpretation of diagnostically valid and clinically relevant images. Sonographers themselves should minimize patient exposure in accordance with the as-low-as-reasonably-achievable principle, particularly for the safety of the eye, lung, and fetus. This practice entails the reduction of output indices or the exposure duration, consistent with the acquisition of diagnostically definitive images. Informed adoption of POCUS worldwide promises a reduction of ionizing radiation risks, enhanced cost-effectiveness, and prompt diagnoses for optimal patient care.


Assuntos
Segurança do Paciente , Sistemas Automatizados de Assistência Junto ao Leito , Ultrassonografia/métodos , Ultrassonografia/normas , Humanos , Ultrassonografia/efeitos adversos
14.
Am J Physiol Heart Circ Physiol ; 317(2): H279-H289, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150271

RESUMO

Increased sympathetic nervous system activity is a hallmark of hypertension (HTN), and it is implicated in altered immune system responses in its pathophysiology. However, the precise mechanisms of neural-immune interaction in HTN remain elusive. We have previously shown an association between elevated sympathetic drive to the bone marrow (BM) and activated BM immune cells in rodent models of HTN. Moreover, microglial-dependent neuroinflammation is also seen in rodent models of HTN. However, the cause-effect relationship between central and systemic inflammatory responses and the sympathetic drive remains unknown. These observations led us to hypothesize that increase in the femoral BM sympathetic nerve activity (fSNA) initiates a cascade of events leading to increase in blood pressure (BP). Here, we investigated the temporal relationship between the BM sympathetic drive, activation of the central and peripheral immune system, and increase in BP in the events leading to established HTN. The present study demonstrates that central infusion of angiotensin II (ANG II) induces early microglial activation in the paraventricular nucleus of hypothalamus, which preceded increase in the fSNA. In turn, activation of fSNA correlated with the timing of increased production and release of CD4+.IL17+ T cells and other proinflammatory cells into circulation and elevation in BP, whereas infiltration of CD4+ cells to the paraventricular nucleus marked establishment of ANG II HTN. This study identifies cellular and molecular mechanisms involved in neural-immune interactions in early and established stages of rodent ANG II HTN. NEW & NOTEWORTHY Early microglia activation in paraventricular nucleus precedes sympathetic activation of the bone marrow. This leads to increased bone marrow immune cells and their release into circulation and an increase in blood pressure. Infiltration of CD4+ T cells into paraventricular nucleus paraventricular nucleus marks late hypertension.


Assuntos
Pressão Sanguínea , Medula Óssea/inervação , Hipertensão/fisiopatologia , Inflamação/fisiopatologia , Neuroimunomodulação , Núcleo Hipotalâmico Paraventricular/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Angiotensina II , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Modelos Animais de Doenças , Fêmur , Hipertensão/induzido quimicamente , Hipertensão/imunologia , Hipertensão/metabolismo , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/metabolismo , Masculino , Microglia/imunologia , Microglia/metabolismo , Núcleo Hipotalâmico Paraventricular/imunologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Ratos Sprague-Dawley , Sistema Nervoso Simpático/imunologia , Sistema Nervoso Simpático/metabolismo , Fatores de Tempo
15.
J Ultrasound Med ; 38(10): 2575-2587, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30702763

RESUMO

OBJECTIVES: Diagnostic ultrasound (DUS) imaging can induce pulmonary capillary hemorrhage (PCH), possibly related to the ultrasonic radiation surface pressure arising from reflection at the lung blood-air interfaces. Acoustic radiation force impulse (ARFI) elastography is a relatively new DUS mode with high-energy "push pulses" used to move tissue and generate shear waves. The objective of this study was to characterize PCH induced by the ARFI elastographic mode for comparison with other previously tested DUS modes. METHODS: Pulmonary capillary hemorrhage induction was examined for ARFI elastographic frames with 5.7-MHz push pulses (Acuson S3000; Siemens Medical Solutions, Mountain View, CA), which had a derated PRPA of 2.6 MPa. Groups of rats with tracheal tube placement had no ventilation (spontaneous breathing), intermittent positive pressure ventilation (IPPV), or IPPV plus 8 cm H2 O of positive end-expiratory pressure (PEEP). Exposure was to 1 or 20 manually triggered image frame acquisitions. The PCH area was measured on the lung surface. RESULTS: All 20-frame exposure groups, and even the single-frame group, had significant PCH relative to shams. Single-frame exposures produced significantly less PCH (P = .002) than 20-frame exposures in rats with a tracheal tube only (spontaneous breathing). The PEEP inhibited the PCH and produced about half of the PCH area induced for IPPV without PEEP (P = .014). CONCLUSIONS: The PCH results were comparable with those from a previous study using B-mode or color Doppler exposure for 5 minutes; however, these modes delivered many more pulses for continuous imaging frames, suggesting that the ARFI elastographic frames were individually much more effective.


Assuntos
Capilares/fisiopatologia , Técnicas de Imagem por Elasticidade/efeitos adversos , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Pneumopatias/diagnóstico por imagem , Pneumopatias/etiologia , Animais , Capilares/diagnóstico por imagem , Modelos Animais de Doenças , Hemorragia/fisiopatologia , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Pneumopatias/fisiopatologia , Ratos
16.
J Ultrasound Med ; 38(7): 1855-1864, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30548874

RESUMO

OBJECTIVES: Contrast-enhanced diagnostic ultrasound (US) has a potential to induce localized biological effects. The potential for contrast-enhanced diagnostic US bioeffects in liver were researched, with guidance from a report by Yang et al (Ultrasonics 2012; 52:1065-1071). METHODS: Contact and standoff scanning was performed for 10 minutes with a diagnostic US phased array at 1.6 MHz during bolus injection or infusion of a contrast agent at a high dose. The impact of the imaging on rat liver was investigated by measuring enzyme release, microvascular leakage, and staining of injured hepatocytes. RESULTS: The results showed liver enzyme release at 30 minutes, indicating liver injury, and elevated extraction of Evans blue dye, indicating microvascular leakage. In addition, Evans blue and trypan blue vital-staining methods revealed scattered stained cells within the US scan plane. For the Evans blue method, fluorescent cell counts in frozen sections were greatest for standoff exposure with contrast infusion. The count decreased strongly with depth for bolus injection, which was probably reflective of the high attenuation noted for this agent delivery method. CONCLUSIONS: The results qualitatively confirmed the report by Yang et al and additionally showed hepatocyte vital staining. Research is needed to determine the threshold for the effects and the contrast agent dose response.


Assuntos
Meios de Contraste/efeitos adversos , Hepatócitos/efeitos dos fármacos , Ultrassonografia , Animais , Azul Evans , Masculino , Ratos , Ratos Sprague-Dawley
17.
Glia ; 66(9): 1915-1928, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29733459

RESUMO

The transactivator of transcription protein, HIV-1 Tat, is linked to neuroAIDS, where degeneration of dopamine neurons occurs. Using a mouse model expressing GFAP-driven Tat protein under doxycycline (Dox) regulation, we investigated microglial-neuronal interactions in the rostral substantia nigra pars compacta (SNc). Immunohistochemistry for microglia and tyrosine hydroxylase (TH) showed that the ratio of microglia to dopamine neurons is smaller in the SNc than in the ventral tegmental area (VTA) and that this difference is maintained following 7-day Dox exposure in wild type animals. Administration of Dox to wild types had no effect on microglial densities. In addressing the sensitivity of neurons to potentially adverse effects of HIV-1 Tat, we found that HIV-1 Tat exposure in vivo selectively decreased TH immunoreactivity in the SNc but not in the VTA, while levels of TH mRNA in the SNc remained unchanged. HIV-1 Tat induction in vivo did not alter the total number of neurons in these brain regions. Application of Tat (5 ng) into dopamine neurons with whole-cell patch pipette decreased spontaneous firing activity. Tat induction also produced a decline in microglial cell numbers, but no microglial activation. Thus, disappearance of dopaminergic phenotype is due to a loss of TH immunoreactivity rather than to neuronal death, which would have triggered microglial activation. We conclude that adverse effects of HIV-1 Tat produce a hypodopamine state by decreasing TH immunoreactivity and firing activity of dopamine neurons. Reduced microglial numbers after Tat exposure in vivo suggest impaired microglial functions and altered bidirectional interactions between dopamine neurons and microglia.


Assuntos
Encéfalo/metabolismo , Neurônios Dopaminérgicos/metabolismo , Microglia/metabolismo , Transmissão Sináptica/fisiologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Animais , Encéfalo/patologia , Encéfalo/virologia , Proteínas de Ligação ao Cálcio/metabolismo , Células Cultivadas , Proteínas de Ligação a DNA , Dopamina/metabolismo , Neurônios Dopaminérgicos/virologia , HIV-1 , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas dos Microfilamentos/metabolismo , Microglia/patologia , Microglia/virologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
18.
J Ultrasound Med ; 37(8): 2021-2028, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29423953

RESUMO

OBJECTIVES: Pulmonary diagnostic ultrasound (US) can induce pulmonary capillary hemorrhage (PCH) in mammals. This singular biological effect of diagnostic US imaging was discovered more than 25 years ago but remains poorly understood. Our objective here was to investigate rapid infusion of intravenous fluids as a possible stressor for capillaries, which might enhance pulmonary diagnostic US-induced PCH. METHODS: Rats were anesthetized with Telazol (Zoetis, Inc, Kalamazoo, MI), which yielded relatively low pulmonary diagnostic US-induced PCH, or Telazol and xylazine, which yielded relatively high pulmonary diagnostic US-induced PCH. Groups of rats were not infused or infused either with normal saline, 10% mannitol, or 5% albumin. Rats were scanned in a warmed water bath with B-mode US for 5 minutes with a 7.6-MHz linear array set to different mechanical index values to obtain exposure response information. Pulmonary capillary hemorrhage was observed as comet tail artifacts in the image and measured on the lung surface. RESULTS: For Telazol anesthesia, all of the PCH results were very low, with no significant differences at the maximum output with an in situ peak rarefactional pressure amplitude of 2.1 MPa (on-screen mechanical index, 0.9). The addition of xylazine to the Telazol anesthetic significantly enhanced the PCH (P < .001) without infusion and likewise for the mannitol and albumin infusion. Saline infusion eliminated this enhancement, with significantly reduced PCH for Telazol-plus-xylazine anesthesia (P < .001); however, both mannitol and albumin infusion resulted in significantly more PCH than saline infusion (P < .01). CONCLUSIONS: These results show PCH dependence on the specific intravenous infusion fluid and illustrate the complex importance of physiologic parameters for US-induced PCH.


Assuntos
Capilares/fisiopatologia , Hidratação/métodos , Hemorragia/etiologia , Hemorragia/prevenção & controle , Pneumopatias/etiologia , Ultrassonografia/efeitos adversos , Albuminas/administração & dosagem , Animais , Modelos Animais de Doenças , Feminino , Hemorragia/fisiopatologia , Infusões Intravenosas , Pulmão/irrigação sanguínea , Pulmão/fisiopatologia , Pneumopatias/fisiopatologia , Manitol/administração & dosagem , Ratos , Ratos Sprague-Dawley , Solução Salina/administração & dosagem
19.
Ann Intern Med ; 166(3): 164-171, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-27893087

RESUMO

BACKGROUND: Alzheimer disease results in progressive functional decline, leading to loss of independence. OBJECTIVE: To determine whether collaborative care plus 2 years of home-based occupational therapy delays functional decline. DESIGN: Randomized, controlled clinical trial. (ClinicalTrials.gov: NCT01314950). SETTING: Urban public health system. PATIENTS: 180 community-dwelling participants with Alzheimer disease and their informal caregivers. INTERVENTION: All participants received collaborative care for dementia. Patients in the intervention group also received in-home occupational therapy delivered in 24 sessions over 2 years. MEASUREMENTS: The primary outcome measure was the Alzheimer's Disease Cooperative Study Group Activities of Daily Living Scale (ADCS ADL); performance-based measures included the Short Physical Performance Battery (SPPB) and Short Portable Sarcopenia Measure (SPSM). RESULTS: At baseline, clinical characteristics did not differ significantly between groups; the mean Mini-Mental State Examination score for both groups was 19 (SD, 7). The intervention group received a median of 18 home visits from the study occupational therapists. In both groups, ADCS ADL scores declined over 24 months. At the primary end point of 24 months, ADCS ADL scores did not differ between groups (mean difference, 2.34 [95% CI, -5.27 to 9.96]). We also could not definitively demonstrate between-group differences in mean SPPB or SPSM values. LIMITATION: The results of this trial are indeterminate and do not rule out potential clinically important effects of the intervention. CONCLUSION: The authors could not definitively demonstrate whether the addition of 2 years of in-home occupational therapy to a collaborative care management model slowed the rate of functional decline among persons with Alzheimer disease. This trial underscores the burden undertaken by caregivers as they provide care for family members with Alzheimer disease and the difficulty in slowing functional decline. PRIMARY FUNDING SOURCE: National Institute on Aging.


Assuntos
Doença de Alzheimer/reabilitação , Serviços de Assistência Domiciliar , Terapia Ocupacional , Atividades Cotidianas , Idoso , Cuidadores , Feminino , Humanos , Masculino , Método Simples-Cego , Resultado do Tratamento
20.
Brain Inj ; 32(3): 342-349, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29333886

RESUMO

OBJECTIVE: To determine early effects on outcome from traumatic brain injury (TBI) induced by controlled cortical impact (CCI) associated with anaemia in mice. HYPOTHESIS: Outcome from TBI with concomitant anaemia would be worse than TBI without anaemia. METHODS: CCI was induced with electromagnetic impaction in four groups of C57BL/6J mice: sham, sham+anaemia; TBI; and TBI+anaemia. Anaemia was created by withdrawal of 30% of calculated intravascular blood volume and saline replacement of equal volume. Functional outcome was assessed by beam-walking test and open field test (after pre-injury training) on post-injury days 3 and 7. After functional assessment, brains removed from sacrificed animals were pathological reviewed with haematoxylin and eosin, cresyl violet, Luxol Fast Blue, and IBA-1 immunostains. RESULTS: Beam-walking was similar between animals with TBI and TBI+anaemia (p = 0.9). In open field test, animals with TBI+anaemia walked less distance than TBI alone or sham animals on days 3 (p < 0.001) and 7 (p < 0.05), indicating less exploratory and locomotion behaviours. No specific pathologic differences could be identified. CONCLUSIONS: Anaemia associated with TBI from CCI is associated with worse outcome as measured by less distance travelled in the open field test at three days than if anaemia is not present.


Assuntos
Anemia/etiologia , Lesões Encefálicas Traumáticas/complicações , Anemia/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Proteínas de Ligação ao Cálcio/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Comportamento Exploratório/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Avaliação de Resultados em Cuidados de Saúde , Transtornos Psicomotores/diagnóstico , Transtornos Psicomotores/etiologia , Estatísticas não Paramétricas
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