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1.
Proc Natl Acad Sci U S A ; 121(25): e2322475121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38857404

RESUMO

Low temperatures and cooling agents like menthol induce cold sensation by activating the peripheral cold receptors TRPM8 and TRPA1, cation channels belonging to the TRP channel family, while the reduction of potassium currents provides an additional and/or synergistic mechanism of cold sensation. Despite extensive studies over the past decades to identify the molecular receptors that mediate thermosensation, cold sensation is still not fully understood and many cold-sensitive peripheral neurons do not express the well-established cold sensor TRPM8. We found that the voltage-gated potassium channel KCNQ1 (Kv7.1), which is defective in cardiac LQT1 syndrome, is, in addition to its known function in the heart, a highly relevant and sex-specific sensor of moderately cold temperatures. We found that KCNQ1 is expressed in skin and dorsal root ganglion neurons, is sensitive to menthol and cooling agents, and is highly sensitive to moderately cold temperatures, in a temperature range at which TRPM8 is not thermosensitive. C-fiber recordings from KCNQ1-/- mice displayed altered action potential firing properties. Strikingly, only male KCNQ1-/- mice showed substantial deficits in cold avoidance at moderately cold temperatures, with a strength of the phenotype similar to that observed in TRPM8-/- animals. While sex-dependent differences in thermal sensitivity have been well documented in humans and mice, KCNQ1 is the first gene reported to play a role in sex-specific temperature sensation. Moreover, we propose that KCNQ1, together with TRPM8, is a key instrumentalist that orchestrates the range and intensity of cold sensation.


Assuntos
Temperatura Baixa , Canal de Potássio KCNQ1 , Sensação Térmica , Animais , Feminino , Masculino , Camundongos , Potenciais de Ação/fisiologia , Gânglios Espinais/metabolismo , Canal de Potássio KCNQ1/metabolismo , Canal de Potássio KCNQ1/genética , Mentol/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sensação Térmica/genética , Canais de Cátion TRPM/metabolismo , Canais de Cátion TRPM/genética
2.
Z Gastroenterol ; 62(7): 1048-1052, 2024 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-38657617

RESUMO

BACKGROUND: Mucinous-cystic neoplasms (MCN) account for 10% of all pancreatic cystic lesions. They are found almost exclusively in females. MCN have an ovarian-like stroma and often estrogen and progesterone receptors. During pregnancy, they can massively increase in size and transform into malignancy. CASE REPORT: We report on a 29-year-old woman in whom a 35mm cyst in the pancreatic tail had been diagnosed several years ago. After workup the lesions had been classified as a pseudocyst. During pregnancy, the cyst massively increased in size and finally was resected. Histology showed a mucinous-cystic neoplasia with focal malignant transformation. CONCLUSION: Cystic neoplasms of the pancreas require a differentiated management. While overtreatment should be avoided, malignant transformation always merits consideration - in particular if the cystic lesion is located in the pancreatic tail. Women with suspected MCN or cystic pancreatic lesions of uncertain etiology should be informed about the (rare) risk of a malignant transformation of an MCN and should be closely monitored during pregnancy.


Assuntos
Transformação Celular Neoplásica , Neoplasias Pancreáticas , Complicações Neoplásicas na Gravidez , Humanos , Feminino , Gravidez , Adulto , Complicações Neoplásicas na Gravidez/patologia , Complicações Neoplásicas na Gravidez/cirurgia , Transformação Celular Neoplásica/patologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Diagnóstico Diferencial
3.
Int J Mol Sci ; 23(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36077033

RESUMO

Traumatic brain injury (TBI) represents a major determining factor of outcome in severely injured patients. However, reliable brain-damage-monitoring markers are still missing. We therefore assessed brain-specific beta-synuclein as a novel blood biomarker of synaptic damage and measured the benchmarks neurofilament light chain (NfL), as a neuroaxonal injury marker, and glial fibrillary acidic protein (GFAP), as an astroglial injury marker, in patients after polytrauma with and without TBI. Compared to healthy volunteers, plasma NfL, beta-synuclein, and GFAP were significantly increased after polytrauma. The markers demonstrated highly distinct time courses, with beta-synuclein and GFAP peaking early and NfL concentrations gradually elevating during the 10-day observation period. Correlation analyses revealed a distinct influence of the extent of extracranial hemorrhage and the severity of head injury on biomarker concentrations. A combined analysis of beta-synuclein and GFAP effectively discriminated between polytrauma patients with and without TBI, despite the comparable severity of injury. Furthermore, we found a good predictive performance for fatal outcome by employing the initial plasma concentrations of NfL, beta-synuclein, and GFAP. Our findings suggest a high diagnostic value of neuronal injury markers reflecting distinct aspects of neuronal injury for the diagnosis of TBI in the complex setting of polytrauma, especially in clinical surroundings with limited imaging opportunities.


Assuntos
Lesões Encefálicas Traumáticas , Traumatismo Múltiplo , Biomarcadores , Lesões Encefálicas Traumáticas/diagnóstico , Proteína Glial Fibrilar Ácida , Humanos , Filamentos Intermediários , beta-Sinucleína
4.
FASEB J ; 32(11): 6159-6173, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29879376

RESUMO

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels encode neuronal and cardiac pacemaker currents. The composition of pacemaker channel complexes in different tissues is poorly understood, and the presence of additional HCN modulating subunits was speculated. Here we show that vesicle-associated membrane protein-associated protein B (VAPB), previously associated with a familial form of amyotrophic lateral sclerosis 8, is an essential HCN1 and HCN2 modulator. VAPB significantly increases HCN2 currents and surface expression and has a major influence on the dendritic neuronal distribution of HCN2. Severe cardiac bradycardias in VAPB-deficient zebrafish and VAPB-/- mice highlight that VAPB physiologically serves to increase cardiac pacemaker currents. An altered T-wave morphology observed in the ECGs of VAPB-/- mice supports the recently proposed role of HCN channels for ventricular repolarization. The critical function of VAPB in native pacemaker channel complexes will be relevant for our understanding of cardiac arrhythmias and epilepsies, and provides an unexpected link between these diseases and amyotrophic lateral sclerosis.-Silbernagel, N., Walecki, M., Schäfer, M.-K. H., Kessler, M., Zobeiri, M., Rinné, S., Kiper, A. K., Komadowski, M. A., Vowinkel, K. S., Wemhöner, K., Fortmüller, L., Schewe, M., Dolga, A. M., Scekic-Zahirovic, J., Matschke, L. A., Culmsee, C., Baukrowitz, T., Monassier, L., Ullrich, N. D., Dupuis, L., Just, S., Budde, T., Fabritz, L., Decher, N. The VAMP-associated protein VAPB is required for cardiac and neuronal pacemaker channel function.


Assuntos
Coração/fisiologia , Ativação do Canal Iônico , Proteínas de Membrana/fisiologia , Neurônios/fisiologia , Marca-Passo Artificial , Animais , Proteínas de Transporte/fisiologia , Embrião não Mamífero/citologia , Embrião não Mamífero/fisiologia , Feminino , Células HeLa , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Camundongos , Camundongos Knockout , Neurônios/citologia , Ratos , Ratos Sprague-Dawley , Proteínas de Transporte Vesicular , Xenopus laevis , Peixe-Zebra
5.
Surg Endosc ; 32(4): 1906-1914, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29218673

RESUMO

BACKGROUND: Esophageal perforations and postoperative leakage of esophagogastrostomies are considered to be life-threatening conditions due to the potential development of mediastinitis and consecutive sepsis. Vacuum-assisted closure (VAC) techniques, a well-established treatment method for superficial infected wounds, are based on a negative pressure applied to the wound via a vacuum-sealed sponge. Endoluminal VAC (E-VAC) therapy as a treatment for GI leakages in the rectum was introduced in 2008. E-VAC therapy is a novel method, and experience regarding esophageal applications is limited. In this retrospective study, the experience of a high-volume center for upper GI surgery with E-VAC therapy in patients with leaks of the upper GI tract is summarized. To our knowledge, this series presents the largest patient cohort worldwide in a single-center study. METHODS: Between October 2010 and January 2017, 77 patients with defects in the upper gastrointestinal tract were treated using the E-VAC application. Six patients had a spontaneous perforation, 12 patients an iatrogenic injury, and 59 patients a postoperative leakage in the upper gastrointestinal tract. RESULTS: Complete restoration of the esophageal defect was achieved in 60 of 77 patients. The average duration of application was 11.0 days, and a median of 2.75 E-VAC systems were used. For 21 of the 77 patients, E-VAC therapy was combined with the placement of self-expanding metal stents. CONCLUSION: This study demonstrates that E-VAC therapy provides an additional treatment option for esophageal wall defects. Esophageal defects and mediastinal abscesses can be treated with E-VAC therapy where endoscopic stenting may not be possible. A prospective multi-center study has to be directed to bring evidence to the superiority of E-VAC therapy for patients suffering from upper GI defects.


Assuntos
Fístula Anastomótica/terapia , Endoscopia/métodos , Perfuração Esofágica/complicações , Tratamento de Ferimentos com Pressão Negativa/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Anastomótica/etiologia , Desenho de Equipamento , Perfuração Esofágica/cirurgia , Feminino , Gastrectomia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
6.
World J Surg ; 40(10): 2405-11, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27216809

RESUMO

BACKGROUND AND AIMS: Delayed gastric emptying after esophagectomy with gastric replacement can pose a significant postoperative problem, often leading to aspiration and pneumonia. The present study analyzes retrospectively the effectiveness of endoscopic pyloric dilatation for post-surgical gastric outlet obstruction. METHODS: Between March 2006 and March 2010, 403 patients underwent a transthoracic en-bloc esophagectomy and reconstruction with a gastric tube and intrathoracic esophagogastrostomy. In patients with postoperative symptoms of an outlet dysfunction and the confirmation by endoscopy, pyloric dilatations were performed without preference with either 20- or 30-mm balloons. RESULTS: A total of 89 balloon dilatations of the pylorus after esophagectomy were performed in 60 (15.6 %) patients. In 21 (35 %) patients, a second dilatation of the pylorus was performed. 55 (61.8 %) dilatations were performed with a 30-mm balloon and 34 (38.2 %) with a 20-mm balloon. The total redilatation rate for the 30-mm balloon was 20 % (n = 11) and 52.9 % (n = 18) for the 20-mm balloon (p < 0.001). All dilatations were performed without any complications. CONCLUSIONS: Pylorus spasm contributes to delayed gastric emptying leading to postoperative complications after esophagectomy. Endoscopic pyloric dilatation after esophagectomy is a safe procedure for treatment of gastric outlet obstruction. The use of a 30-mm balloon has the same safety profile but a 2.5 lower redilatation rate compared to the 20-mm balloon. Thus, the use of 20-mm balloons has been abandoned in our clinic.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/efeitos adversos , Obstrução da Saída Gástrica/cirurgia , Complicações Pós-Operatórias/cirurgia , Adulto , Idoso , Dilatação , Endoscopia/efeitos adversos , Feminino , Esvaziamento Gástrico , Humanos , Masculino , Pessoa de Meia-Idade , Piloro/cirurgia , Estudos Retrospectivos
7.
Cell Mol Neurobiol ; 35(2): 205-16, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25239161

RESUMO

Expression of Satb2 (Special AT-rich sequence-binding protein-2) elicits expression of the vesicular acetylcholine transporter (VAChT) and choline acetyltransferase (ChAT) in cultured rat sympathetic neurons exposed to soluble differentiation factors. Here, we determined whether or not Satb2 plays a similar role in cholinergic differentiation in vivo, by comparing the postnatal profile of Satb2 expression in the rodent stellate ganglion to that of VAChT and ChAT. Throughout postnatal development, VAChT and ChAT were found to be co-expressed in a numerically stable subpopulation of rat stellate ganglion neurons. Nerve fibers innervating rat forepaw sweat glands on P1 were VAChT immunoreactive, while ChAT was detectable at this target only after P5. The postnatal abundance of VAChT transcripts in the stellate ganglion was at maximum already on P1, whereas ChAT mRNA levels increased from low levels on P1 to reach maximum levels between P5 and P21. Satb2 mRNA was detected in cholinergic neurons in the stellate ganglion beginning with P8, thus coincident with the onset of unequivocal detection of ChAT immunoreactivity in forepaw sweat gland endings. Satb2 knockout mice exhibited no change in the P1 cholinergic VAChT/ChAT co-phenotype in stellate ganglion neurons. Thus, cholinergic phenotype maturation involves first, early target (sweat-gland)-independent expression and trafficking of VAChT, and later, potentially target- and Satb2-dependent elevation of ChAT mRNA and protein transport into sweat gland endings. In rat sudomotor neurons that, unlike mouse sudomotor neurons, co-express calcitonin gene-related peptide (CGRP), Satb2 may also be related to the establishment of species-specific neuropeptide co-phenotypes during postnatal development.


Assuntos
Neurônios Colinérgicos/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Atividade Motora , Fatores de Transcrição/metabolismo , Animais , Animais Recém-Nascidos , Especificidade de Anticorpos , Biomarcadores/metabolismo , Extremidades/inervação , Feminino , Regulação da Expressão Gênica , Masculino , Proteínas de Ligação à Região de Interação com a Matriz/deficiência , Proteínas de Ligação à Região de Interação com a Matriz/genética , Camundongos Endogâmicos BALB C , Peptídeos/metabolismo , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Gânglio Estrelado/metabolismo , Glândulas Sudoríparas/inervação , Sistema Nervoso Simpático/metabolismo , Fatores de Tempo , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Proteínas Vesiculares de Transporte de Acetilcolina
8.
Brain Behav Immun ; 38: 100-10, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24440144

RESUMO

The sympathetic nervous system (SNS) plays a crucial role in the course and development of autoimmune disease in Fas-deficient lpr/lpr mice. As regulatory T cells (Tregs) are considered important modulators of autoimmune processes, we analyzed the interaction between the SNS and Tregs in this murine model of lymphoproliferative disease. We found that the percentage of Tregs among CD4(+) T cells is increased in the spleen, lymph nodes, and thymus of lpr/lpr mice as compared to age-matched C57Bl/6J (B6) mice. Furthermore, noradrenaline (NA), the main sympathetic neurotransmitter, induced apoptosis in B6- and lpr/lpr-derived Tregs. NA also reduced the frequency of Foxp3(+) cells and Foxp3 mRNA expression via ß2-adrenoceptor (ß2-AR)-mediated mechanisms in a concentration and time-dependent manner. Destruction of peripheral sympathetic nerves by 6-hydroxydopamine significantly increased the percentage of Tregs in B6 control mice to an extent comparable to aged-matched lpr/lpr mice. The concentration of splenic NA negatively correlated with the frequency of CD4(+)Foxp3(+) Tregs. Additionally, 60days after sympathectomy, a partial recovery of NA concentrations led to Treg percentages comparable to those of intact, vehicle-treated controls. Immunohistochemical analysis of the spleen revealed localization of single Foxp3(+) Tregs in proximity to NA-producing nerve fibers, providing an interface between Tregs and the SNS. Taken together, our data suggest a relation between the degree of splenic sympathetic innervation and the size of the Treg compartment. While there are few examples of endogenous substances capable of affecting Tregs, our results provide a possible explanation of how the magnitude of the Treg compartment in the spleen can be regulated by the SNS.


Assuntos
Apoptose , Fatores de Transcrição Forkhead/metabolismo , Transtornos Linfoproliferativos/imunologia , Norepinefrina/metabolismo , Sistema Nervoso Simpático/metabolismo , Linfócitos T Reguladores/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Transtornos Linfoproliferativos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Baço/inervação , Baço/metabolismo
9.
Nat Commun ; 15(1): 7548, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39215006

RESUMO

TASK-5 (KCNK15) belongs to the acid-sensitive subfamily of two-pore domain potassium (K2P) channels, which includes TASK-1 and TASK-3. TASK-5 stands out as K2P channel for which there is no functional data available, since it was reported in 2001 as non-functional and thus "silent". Here we show that TASK-5 channels are indeed non-functional as homodimers, but are involved in the formation of functional channel complexes with TASK-1 and TASK-3. TASK-5 negatively modulates the surface expression of TASK channels, while the heteromeric TASK-5-containing channel complexes located at the plasma membrane are characterized by changes in single-channel conductance, Gq-coupled receptor-mediated channel inhibition, and sensitivity to TASK modulators. The unique pharmacology of TASK-1/TASK-5 heterodimers, affected by a common polymorphism in KCNK15, needs to be carefully considered in the future development of drugs targeting TASK channels. Our observations provide an access to study TASK-5 at the functional level, particularly in malignant cancers associated with KCNK15.


Assuntos
Proteínas do Tecido Nervoso , Canais de Potássio de Domínios Poros em Tandem , Animais , Humanos , Membrana Celular/metabolismo , Células HEK293 , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Canais de Potássio de Domínios Poros em Tandem/genética , Multimerização Proteica
10.
iScience ; 27(5): 109696, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38689644

RESUMO

Popeye domain containing (POPDC) proteins are predominantly expressed in the heart and skeletal muscle, modulating the K2P potassium channel TREK-1 in a cAMP-dependent manner. POPDC1 and POPDC2 variants cause cardiac conduction disorders with or without muscular dystrophy. Searching for POPDC2-modulated ion channels using a functional co-expression screen in Xenopus oocytes, we found POPDC proteins to modulate the cardiac sodium channel Nav1.5. POPDC proteins downregulate Nav1.5 currents in a cAMP-dependent manner by reducing the surface expression of the channel. POPDC2 and Nav1.5 are both expressed in different regions of the murine heart and consistently POPDC2 co-immunoprecipitates with Nav1.5 from native cardiac tissue. Strikingly, the knock-down of popdc2 in embryonic zebrafish caused an increased upstroke velocity and overshoot of cardiac action potentials. The POPDC modulation of Nav1.5 provides a new mechanism to regulate cardiac sodium channel densities under sympathetic stimulation, which is likely to have a functional impact on cardiac physiology and inherited arrhythmias.

11.
Neurobiol Dis ; 54: 32-42, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23466699

RESUMO

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a pleiotropic peptide with autocrine neuroprotective and paracrine anti-inflammatory properties in various models of acute neuronal damage and neurodegenerative diseases. Therefore, we examined a possible beneficial role of endogenous PACAP in the superoxide dismutase 1, SOD1(G93A), mouse model of amyotrophic lateral sclerosis (ALS), a lethal neurodegenerative disease particularly affecting somatomotor neurons. In wild-type mice, somatomotor and visceromotor neurons in brain stem and spinal cord were found to express the PACAP specific receptor PAC1, but only visceromotor neurons expressed PACAP as a potential autocrine source of regulation of these receptors. In SOD1(G93A) mice, only a small subset of the surviving somatomotor neurons showed induction of PACAP mRNA, and somatomotor neuron degeneration was unchanged in PACAP-deficient SOD1(G93A) mice. Pre-ganglionic sympathetic visceromotor neurons were found to be resistant in SOD1(G93A) mice, while pre-ganglionic parasympathetic neurons degenerated during ALS disease progression in this mouse model. PACAP-deficient SOD1(G93A) mice showed even greater pre-ganglionic parasympathetic neuron loss compared to SOD1(G93A) mice, and additional degeneration of pre-ganglionic sympathetic neurons. Thus, constitutive expression of PACAP and PAC1 may confer neuroprotection to central visceromotor neurons in SOD1(G93A) mice via autocrine pathways. Regarding the progression of neuroinflammation, the switch from amoeboid to hypertrophic microglial phenotype observed in SOD1(G93A) mice was absent in PACAP-deficient SOD1(G93A) mice. Thus, endogenous PACAP may promote microglial cytodestructive functions thought to drive ALS disease progression. This hypothesis was consistent with prolongation of life expectancy and preserved tongue motor function in PACAP-deficient SOD1(G93A) mice, compared to SOD1(G93A) mice. Given the protective role of PACAP expression in visceromotor neurons and the opposing effect on microglial function in SOD1(G93A) mice, both PACAP agonism and antagonism may be promising therapeutic tools for ALS treatment, if stage of disease progression and targeting the specific auto- and paracrine signaling pathways are carefully considered.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Degeneração Neural/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Transdução de Sinais/fisiologia , Esclerose Lateral Amiotrófica/patologia , Animais , Modelos Animais de Doenças , Progressão da Doença , Humanos , Imuno-Histoquímica , Hibridização In Situ , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Camundongos Transgênicos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Degeneração Neural/patologia , Superóxido Dismutase/genética , Superóxido Dismutase-1
12.
Brain Sci ; 12(11)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36358402

RESUMO

Rats, which are highly social animals, are known to communicate using ultrasonic vocalizations (USV) in different frequency ranges. Calls around 50 kHz are related to positive affective states and promote social interactions. Our previous work has shown that the playback of natural 50-kHz USV leads to a strong social approach response toward the sound source, which is related to activation in the nucleus accumbens. In male Wistar rats, the behavioral response habituates, that is, becomes weaker or is even absent, when such playback is repeated several days later, an outcome found to be memory-dependent. Here, we asked whether such habituation is due to the lack of a contingent social consequence after playback in the initial test and whether activation of the nucleus accumbens, as measured by c-fos immunohistochemistry, can still be observed in a retest. To this end, groups of young male Wistar rats underwent an initial 50-kHz USV playback test, immediately after which they were either (1) kept temporarily alone, (2) exposed to a same-sex juvenile, or (3) to their own housing group. One week later, they underwent a retest with playback; this time not followed by social consequences but by brain removal for c-fos immunohistochemistry. Consistent with previous reports, behavioral changes evoked by the initial exposure to 50-kHz USV playback included a strong approach response. In the retest, no such response was found, irrespective of whether rats had experienced a contingent social consequence after the initial test or not. At the neural level, no substantial c-fos activation was found in the nucleus accumbens, but unexpected strong activation was detected in the anterior cingulate cortex, with some of it in GABAergic cells. The c-fos patterns did not differ between groups but cell numbers were individually correlated with behavior, i.e., rats that still approached in response to playback in the retest showed more activation. Together, these data do not provide substantial evidence that the lack of a contingent social consequence after 50-kHz USV playback accounts for approach habituation in the retest. Additionally, there is apparently no substantial activation of the nucleus accumbens in the retest, whereas the exploratory findings in the anterior cingulate cortex indicate that this brain area might be involved when individual rats still approach 50-kHz USV playback.

13.
Front Cell Neurosci ; 16: 820127, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35221925

RESUMO

The activation of microglia and the infiltration of macrophages are hallmarks of neuroinflammation after acute brain injuries, including traumatic brain injury (TBI). The two myeloid populations share many features in the post-injury inflammatory response, thus, being antigenically indistinguishable. Recently Tmem119, a type I transmembrane protein specifically expressed by microglia under physiological conditions, was proposed as a tool to differentiate resident microglia from blood-borne macrophages, not expressing it. However, the validity of Tmem119 as a specific marker of resident microglia in the context of acute brain injury, where microglia are activated and macrophages are recruited, needs validation. Our purpose was to investigate Tmem119 expression and distribution in relation to the morphology of brain myeloid cells present in the injured area after TBI. Mice underwent sham surgery or TBI by controlled cortical impact (CCI). Brains from sham-operated, or TBI mice, were analyzed by in situ hybridization to identify the cells expressing Tmem119, and by Western blot and quantitative immunofluorescence to measure Tmem119 protein levels in the entire brain regions and single cells. The morphology of Iba1+ myeloid cells was analyzed at different times (4 and 7 days after TBI) and several distances from the contused edge in order to associate Tmem119 expression with morphological evolution of active microglia. In situ hybridization indicated an increased Tmem119 RNA along with increased microglial complement C1q activation in the contused area and surrounding regions. On the contrary, the biochemical evaluation showed a drop in Tmem119 protein levels in the same areas. The Tmem119 immunoreactivity decreased in Iba1+ myeloid cells found in the contused cortex at both time points, with the cells showing the hypertrophic ameboid morphology having no Tmem119 expression. The Tmem119 was present on ramifications of resident microglia and its presence was decreased as a consequence of microglial activation in cortical areas close to contusion. Based on the data, we conclude that the decrease of Tmem119 in reactive microglia may depend on the process of microglial activation, which involves the retracting of their branchings to acquire an ameboid shape. The Tmem119 immunoreactivity decreases in reactive microglia to similar levels than the blood-borne macrophages, thus, failing to discriminate the two myeloid populations after TBI.

14.
J Cell Biol ; 128(6): 1145-62, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7896878

RESUMO

Cell cycle progression for postembryonic cells requires the activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-R), the enzyme which catalyzes the production of the isoprenoid precursor, mevalonate. In this study, we examine the requirements of HMG-R activity for cell cycle progression during the meiotic and early mitotic divisions using oocytes and dividing embryos from the surf clam, Spisula solidissima. Using two different inhibitors of HMG-R, we find that the activity of this enzyme appears to be required at three distinct points of the cell cycle during meiosis. Depending on the stage at which these inhibitors are added to synchronous clam cultures, a reversible cell cycle block is triggered at the time of activation or at metaphase of either meiosis I or II, whereas there is not block to the mitotic cell cycle. Inhibition of HMG-R activity in activated oocytes does not affect the transient activation of p42MAPK but results in a block at metaphase of meiosis I that is accompanied by the stabilization of cyclins A and B and p34cdc2 kinase activity. Our results suggest that metabolites from the mevalonate biosynthetic pathway can act to influence the process of activation, as well as the events later in the cell cycle that lead to cyclin proteolysis and the exit from M phase during clam meiosis.


Assuntos
Bivalves/citologia , Inibidores de Hidroximetilglutaril-CoA Redutases , Oócitos/citologia , Animais , Ciclo Celular/efeitos dos fármacos , Ciclinas/metabolismo , Feminino , Hidroximetilglutaril-CoA Redutases/metabolismo , Hidroximetilglutaril-CoA-Redutases NADP-Dependentes , Lovastatina/farmacologia , Meiose/efeitos dos fármacos , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo
15.
Front Neurosci ; 13: 1281, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31866806

RESUMO

Results from a variety of sources indicate a role for pituitary adenylate cyclase-activating polypeptide (PACAP) in light/glutamate-induced phase resetting of the circadian clock mediated by the retinohypothalamic tract (RHT). Attempts to block or remove PACAP's contribution to clock-resetting have generated phenotypes that differ in their responses to light or glutamate. For example, previous studies of circadian behaviors found that period-maintenance and early-night phase delays are intact in PACAP-null mice, yet there is a consistent deficit in behavioral phase-resetting to light stimulation in the late night. Here we report rodent stimulus-response characteristics of PACAP release from the RHT, and map these to responses of the suprachiasmatic nucleus (SCN) in intact and PACAP-deficient mouse hypothalamus with regard to phase-resetting. SCN of PACAP-null mice exhibit normal circadian rhythms in neuronal activity, but are "blind" to glutamate stimulating phase-advance responses in late night, although not in early night, consistent with previously reported selective lack of late-night light behavioral responsiveness of these mice. Induction of CREB phosphorylation, a hallmark of the light/glutamate response of the SCN, also is absent in SCN-containing ex vivo slices from PACAP-deficient mouse hypothalamus. PACAP replacement to the SCN of PACAP-null mice restored wild-type phase-shifting of firing-rate patterns in response to glutamate applied to the SCN in late night. Likewise, ex vivo SCN of wild-type mice post-orbital enucleation are unresponsive to glutamate unless PACAP also is restored. Furthermore, we demonstrate that the period of efficacy of PACAP at SCN nerve terminals corresponds to waxing of PACAP mRNA expression in ipRGCs during the night, and waning during the day. These results validate the use of PACAP-deficient mice in defining the role and specificity of PACAP as a co-transmitter with glutamate in ipRGC-RHT projections to SCN in phase advancing the SCN circadian rhythm in late night.

16.
Int Health ; 10(suppl_1): i97-i101, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29471339

RESUMO

The NGDO Coordination Group for the Control of Onchocerciasis was launched in 1992, and with the paradigm shift from control of disease to elimination of onchocerciasis transmission, the Group shifted its orientation to that new paradigm in 2013. It also changed its name, replacing 'control' with 'elimination.' In doing so, the Group has repositioned itself to build on the successes of the past to finish the job it began over 25 years ago.


Assuntos
Erradicação de Doenças/organização & administração , Internacionalidade , Oncocercose/prevenção & controle , Animais , Antiparasitários/uso terapêutico , Humanos , Ivermectina/uso terapêutico , Oncocercose/tratamento farmacológico
17.
J Laparoendosc Adv Surg Tech A ; 28(4): 422-428, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29327976

RESUMO

BACKGROUND: Perforation of the esophagus is the most severe complication of transesophageal echocardiography (TEE) and can lead to mediastinitis, pleural empyema, or peritonitis. Currently, the majority of patients receive operative treatment with only 6% treated endoscopically. We report our experience with endoscopic and conservative approaches. METHODS: We retrospectively reviewed all patients treated for esophageal perforation and included all patients with perforation caused by TEE. All patients with perforation of the esophagus by TEE probe underwent conservative or endoscopic treatment, drainage of pleural and mediastinal retentions, and adjusted to antibiotic therapy. RESULTS: From January 2004 to December 2014 a total of 109 patients were treated for esophageal perforation in our department. In 6 patients (5.5%) the perforation was caused by TEE. Location was cervical and midthoracic in 2 and 4 cases, respectively. All patients underwent successful endoscopic treatment and no further surgical procedure, such as esophageal suture or resection was necessary. The mean time between TEE and therapy of the perforation was 7.3 days. In all patients closure of the leakage could be achieved within 30 days. Mortality rate was 0%. CONCLUSIONS: Esophageal perforations caused by TEE are typically small, in the cervical and mid esophagus, and minimally contaminated. These are good prognostic factors for successful endoscopic treatment with preservation of the esophagus. Operative treatment should only be considered in cases of failed endoscopic treatment.


Assuntos
Tratamento Conservador , Ecocardiografia Transesofagiana/efeitos adversos , Endoscopia Gastrointestinal , Perfuração Esofágica/etiologia , Perfuração Esofágica/terapia , Adulto , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Drenagem , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
18.
Neurochem Int ; 50(1): 281-90, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17045702

RESUMO

To examine the role of the vanilloid receptor TRPV1 in neuropathic pain, we assessed the effects of the receptor antagonist thioxo-BCTC and antisense oligonucleotides against the TRPV1 mRNA in a rat model of spinal nerve ligation. In order to identify accessible sites on the mRNA of TRPV1, the RNase H assay was used, leading to the successful identification of binding sites for antisense oligonucleotides. Cotransfection studies using Cos-7 cells were employed to identify the most effective antisense oligonucleotide efficiently inhibiting the expression of a fusion protein consisting of TRPV1 and the green fluorescent protein in a specific and concentration-dependent manner. In an in vivo rat model of spinal nerve ligation, intravenous application of the TRPV1 antagonist thioxo-BCTC reduced mechanical hypersensitivity yielding an ED(50) value of 10.6mg/kg. Intrathecal administration of the antisense oligonucleotide against TRPV1, but not the mismatch oligonucleotide or a vehicle control, reduced mechanical hypersensitivity in rats with spinal nerve ligation in a similar manner. Immunohistochemical analysis revealed neuropathy- and antisense-associated regulation of TRPV1 protein expression in spinal cord and dorsal root ganglia. Our data demonstrate comparative analgesic effects of a TRPV1 anatagonist and a rationally designed TRPV1 antisense oligonucleotide in a spinal nerve ligation model of neuropathic pain and thus, lend support to the validation of TRPV1 as a promising target for the treatment of neuropathic pain.


Assuntos
Analgésicos/farmacologia , Oligonucleotídeos Antissenso/farmacologia , Canais de Cátion TRPV/efeitos dos fármacos , Animais , Sequência de Bases , Células CHO , Células COS , Chlorocebus aethiops , Cricetinae , Cricetulus , Primers do DNA , Imuno-Histoquímica , Masculino , Microscopia de Fluorescência , Ratos , Ratos Sprague-Dawley , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo
19.
Case Rep Orthop ; 2017: 3792610, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29038741

RESUMO

The Ligament Augmentation and Reconstruction System® (LARS®) represents a popular synthetic anatomical reduction method for acromioclavicular joint dislocation by means of coracoclavicular ligament reconstruction. To our knowledge, no early failure has been documented in the literature. We present two unusual cases of LARS failure, one at four months after implant and the other at three weeks, without obvious causes, requiring re-do reconstruction, and discuss potential contributory factors.

20.
Sci Rep ; 7(1): 1751, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28496188

RESUMO

There is an ongoing search for new tracers to optimize imaging of beta cell-derived tumors (insulinomas). The PAC1 receptor, expressed by insulinomas, can be used for targeting of these tumors. Here, we investigated whether radiolabeled maxadilan could be used for insulinoma imaging. Maxadilan was C- or N-terminally conjugated with DTPA (termed maxadilan-DPTA or DTPA-maxadilan respectively). BALB/c nude mice bearing subcutaneous INS-1 tumors were injected with either In-111-labeled maxadilan-DTPA or In-111-DTPA-maxadilan. Biodistribution studies were carried out at 1, 2 and 4 hours after injection and SPECT/CT imaging 1 and 4 hours after injection of maxadilan-DTPA-111In. Radiolabeling of maxadilan-DTPA (680 MBq/nmol) was more efficient than of DTPA-maxadilan (55 MBq/nmol). Conjugation with DTPA slightly reduced receptor binding affinity in vitro: IC50 values were 3.2, 21.0 and 21.0 nM for maxadilan, natIn-DTPA-maxadilan and maxadilan-DTPA-natIn respectively. Upon i.v. injection maxadilan-DTPA-111In accumulated specifically in INS-1 tumors (7.30 ± 1.87%ID/g) and in the pancreas (3.82 ± 0.22%ID/g). INS-1 tumors were clearly visualized by small animal SPECT/CT. In conclusion, this study showed that the high affinity of maxadilan to the PAC1 receptor was maintained after DTPA conjugation. Furthermore, radiolabeled maxadilan-DTPA accumulated specifically in INS-1 tumors and, therefore, may qualify as a useful tracer to image insulinomas.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Proteínas de Insetos/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Sequência de Aminoácidos , Animais , Ligação Competitiva , Linhagem Celular Tumoral , Intervalos de Confiança , Humanos , Radioisótopos de Índio/química , Concentração Inibidora 50 , Proteínas de Insetos/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ácido Pentético/química , Compostos Radiofarmacêuticos/química , Ratos , Soro/metabolismo , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único
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