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1.
Clin Genet ; 94(1): 54-60, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29120068

RESUMO

Alacrima, the lack of tears, is a rare clinical finding that has been reported as a feature of multiple genetic disorders and can serve as a diagnostic clue to some rare conditions. Causes of alacrima range from absence/hyposecretion of tears to agenesis or improper development of lacrimal gland ducts and associated structures. There are 13 known heritable disorders featuring varying degrees and causes of alacrima. Some manifest only the congenital absence of tears, while others affect multiple organ systems and may involve severe developmental delay, intellectual disability, and potentially life-threatening autonomic dysregulation. To aid in the diagnosis for patients manifesting alacrima, we review the major causes and the various genetic disorders associated with alacrima and provide a differential template for diagnosis.


Assuntos
Oftalmopatias Hereditárias/diagnóstico , Oftalmopatias Hereditárias/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Doenças do Aparelho Lacrimal/diagnóstico , Doenças do Aparelho Lacrimal/genética , Algoritmos , Alelos , Diagnóstico Diferencial , Estudos de Associação Genética/métodos , Marcadores Genéticos , Humanos , Fenótipo , Guias de Prática Clínica como Assunto
2.
J Neurooncol ; 113(3): 385-96, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23666203

RESUMO

Meningiomas, the most frequent benign intracranial and intraspinal types of tumors are normally removed by surgery. Complications can occur when the tumor is critically localized and cannot be completely removed or when comorbidities of the mostly elder patients increase the general surgical risk. Thus, alternate medical treatment concepts for the therapy of meningiomas would be desirable. Curcumin, the active ingredient of the spice plant Curcuma longa has shown anti-tumorigenic actions in many different types of tumors and therefore, its effect on growth and apoptosis of meningioma cells was studied in the present paper. In vitro, treatment of the human Ben-Men-1 meningioma cell line and of a series of 21 primary human meningioma cell cultures with curcumin (1-20 µM) strongly reduced the proliferation in all cases in a dose dependent manner. Cell cycle analysis by fluorescence-activated cell sorting showed growth arrest at G2/M phase, which was confirmed by demonstrating the corresponding modulation of proteins involved in G2/M arrest by immunoblotting and/or confocal laser microscopy. High dosages (20, 50 µM) of curcumin induced a significant increase of apoptosis in Ben-Men-1 and primary meningioma cell cultures as demonstrated by morphological changes of cell nuclei, DNA fragmentation, translocation of cell membrane associated phosphatidyl serine and the induction of apoptotic-acting cleaved caspase-3. Our results suggest that the multi-targeting drug curcumin has potent anti-tumorigenic actions in meningioma cells and might therefore be a putative candidate for the pharmacological treatment of meningiomas.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Curcumina/farmacologia , Neoplasias Meníngeas/patologia , Meningioma/patologia , Western Blotting , Ciclo Celular/efeitos dos fármacos , Citometria de Fluxo , Imunofluorescência , Humanos , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Células Tumorais Cultivadas
3.
AJNR Am J Neuroradiol ; 44(2): 212-217, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36702506

RESUMO

Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS) is a rare autosomal dominant syndrome secondary to mutations in NR2F1 (COUP-TF1), characterized by visual impairment secondary to optic nerve hypoplasia and/or atrophy, developmental and cognitive delay, and seizures. This study reports common neuroimaging findings in a cohort of 21 individuals with BBSOAS that collectively suggest the diagnosis. These include mesial temporal dysgyria, perisylvian dysgyria, posterior predominant white matter volume loss, callosal abnormalities, lacrimal gland abnormalities, and optic nerve volume loss.


Assuntos
Deficiência Intelectual , Atrofia Óptica , Humanos , Fator I de Transcrição COUP/genética , Mutação , Atrofia Óptica/diagnóstico por imagem , Neuroimagem
4.
NPJ Precis Oncol ; 6(1): 36, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35681079

RESUMO

Homologous repair deficiency (HRD) is present in many cancer types at variable prevalence and can indicate response to platinum-based chemotherapy and PARP inhibition. We developed a tumor classification system based on the loss of function of genes in the homologous recombination repair (HRR) pathway. To this end, somatic and germline alterations in BRCA1/2 and 140 other HRR genes were included and assessed for the impact on gene function. Additionally, information on the allelic hit type and on BRCA1 promoter hypermethylation was included. The HRDsum score including LOH, LST, and TAI was calculated for 8847 tumors of the TCGA cohort starting from genotyping data and for the subcohort of ovarian cancer also starting from WES data. Pan-cancer, deleterious BRCA1/2 alterations were detected in 4% of the tumors, while 18% of the tumors were HRD-positive (HRDsum ≥ 42). Across 33 cancer types, both BRCA1/2 alterations and HRD-positivity were most prevalent in ovarian cancer (20% and 69%). Pan-cancer, tumors with biallelic deleterious alterations in BRCA1/2 were separated strongly from tumors without relevant alterations (AUC = 0.89), while separation for tumors with monoallelic deleterious BRCA1/2 alterations was weak (AUC = 0.53). Tumors with biallelic deleterious alterations in other HHR genes were separated moderately from tumors without relevant alterations (AUC = 0.63), while separation for tumors with such monoallelic alterations was weaker (AUC = 0.57). In ovarian cancer, HRDsum scores calculated from WES data correlated strongly with HRDsum scores calculated from genotyping data (R = 0.87) and were slightly (4%) higher. We comprehensively analyzed HRD scores and their association with mutations in HRR genes in common cancer types. Our study identifies important parameters influencing HRD measurement and argues for an integration of HRDsum score with specific mutational profiles.

5.
J Dent Res ; 101(3): 323-330, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34528480

RESUMO

Nonsyndromic cleft lip with or without palate (nsCL/P) ranks among the most common human birth defects and has a multifactorial etiology. Human neural crest cells (hNCC) make a substantial contribution to the formation of facial bone and cartilage and are a key cell type in terms of nsCL/P etiology. Based on increasing evidence for the role of noncoding regulatory mechanisms in nsCL/P, we investigated the role of hNCC-expressed microRNAs (miRNA) in cleft development. First, we conducted a systematic analysis of miRNAs expressed in human-induced pluripotent stem cell-derived hNCC using Affymetrix microarrays on cell lines established from 4 unaffected donors. These analyses identified 152 candidate miRNAs. Based on the hypothesis that candidate miRNA loci harbor genetic variation associated with nsCL/P risk, the genomic locations of these candidates were cross-referenced with data from a previous genome-wide association study of nsCL/P. Associated variants were reanalyzed in independent nsCL/P study populations. Jointly, the results suggest that miR-149 is implicated in nsCL/P etiology. Second, functional follow-up included in vitro overexpression and inhibition of miR-149 in hNCC and subsequent analyses at the molecular and phenotypic level. Using 3'RNA-Seq, we identified 604 differentially expressed (DE) genes in hNCC overexpressing miR-149 compared with untreated cells. These included TLR4 and JUNB, which are established targets of miR-149, and NOG, BMP4, and PAX6, which are reported nsCL/P candidate genes. Pathway analyses revealed that DE genes were enriched in pathways including regulation of cartilage development and NCC differentiation. At the cellular level, distinct hNCC migration patterns were observed in response to miR-149 overexpression. Our data suggest that miR-149 is involved in the etiology of nsCL/P via its role in hNCC migration.


Assuntos
Fenda Labial , Fissura Palatina , MicroRNAs , Estudos de Casos e Controles , Fenda Labial/genética , Fissura Palatina/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , MicroRNAs/genética , Crista Neural , Polimorfismo de Nucleotídeo Único
6.
ESMO Open ; 7(6): 100637, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36423362

RESUMO

BACKGROUND: COGNITION (Comprehensive assessment of clinical features, genomics and further molecular markers to identify patients with early breast cancer for enrolment on marker driven trials) is a diagnostic registry trial that employs genomic and transcriptomic profiling to identify biomarkers in patients with early breast cancer with a high risk for relapse after standard neoadjuvant chemotherapy (NACT) to guide genomics-driven targeted post-neoadjuvant therapy. PATIENTS AND METHODS: At National Center for Tumor Diseases Heidelberg patients were biopsied before starting NACT, and for patients with residual tumors after NACT additional biopsy material was collected. Whole-genome/exome and transcriptome sequencing were applied on tumor and corresponding blood samples. RESULTS: In the pilot phase 255 patients were enrolled, among which 213 were assessable: thereof 48.8% were identified to be at a high risk for relapse following NACT; 86.4% of 81 patients discussed in the molecular tumor board were eligible for a targeted therapy within the interventional multiarm phase II trial COGNITION-GUIDE (Genomics-guided targeted post neoadjuvant therapy in patients with early breast cancer) starting enrolment in Q4/2022. An in-depth longitudinal analysis at baseline and in residual tumor tissue of 16 patients revealed some cases with clonal evolution but largely stable genetic alterations, suggesting restricted selective pressure of broad-acting cytotoxic neoadjuvant chemotherapies. CONCLUSIONS: While most precision oncology initiatives focus on metastatic disease, the presented concept offers the opportunity to empower novel therapy options for patients with high-risk early breast cancer in the post-neoadjuvant setting within a biomarker-driven trial and provides the basis to test the value of precision oncology in a curative setting with the overarching goal to increase cure rates.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Recidiva Local de Neoplasia/tratamento farmacológico , Medicina de Precisão , Estudos Prospectivos
7.
Placenta ; 88: 36-43, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31670095

RESUMO

INTRODUCTION: There are considerable variations in villous morphology within a normal placenta. However, whether there is a reproducible spatial pattern of variation in villous vascular density is not known. Micro-CT provides three-dimensional volume imaging with spatial resolution down to the micrometre scale. In this study, we applied Micro-CT and histological analysis to investigate the degree of heterogeneity of vascularisation within the placenta. METHOD: Ten term placentas were collected at elective caesarean section, perfused with contrast agent and imaged whole with Micro-CT. Eight full depth tissue blocks were then taken from each placenta and imaged. Sections were taken for histological analysis. Data was analysed to investigate vascular fill, and vascular density in relation to location from cord insertion to placental edge at each scale. RESULTS: Whole placental imaging revealed no spatially consistent difference in villous vessel density within the main placental tissue, although there was a great degree of heterogeneity. Both block imaging and histological analysis found a large degree of heterogeneity of vascular density within placentas, but no strong correlation between villous vascular density and block location (rs = 0.066, p = 0.7 block imaging, rs = 0.06, p = 0.6 histological analysis). DISCUSSION: This work presents a novel method for imaging the human placenta vascular tree using multiscale Micro-CT imaging. It demonstrates that there is a large degree of variation in vascular density throughout normal term human placentas. The three-dimensional data created by this technique could be used, with more advanced computer analysis, to further investigate the structure of the vascular tree.


Assuntos
Placenta/irrigação sanguínea , Microtomografia por Raio-X , Adulto , Variação Anatômica , Feminino , Humanos , Placenta/diagnóstico por imagem , Gravidez
8.
Interface Focus ; 8(2): 20170044, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29503723

RESUMO

Contemporary terrestrial laser scanning (TLS) is being used widely in forest ecology applications to examine ecosystem properties at increasing spatial and temporal scales. Harvard Forest (HF) in Petersham, MA, USA, is a long-term ecological research (LTER) site, a National Ecological Observatory Network (NEON) location and contains a 35 ha plot which is part of Smithsonian Institution's Forest Global Earth Observatory (ForestGEO). The combination of long-term field plots, eddy flux towers and the detailed past historical records has made HF very appealing for a variety of remote sensing studies. Terrestrial laser scanners, including three pioneering research instruments: the Echidna Validation Instrument, the Dual-Wavelength Echidna Lidar and the Compact Biomass Lidar, have already been used both independently and in conjunction with airborne laser scanning data and forest census data to characterize forest dynamics. TLS approaches include three-dimensional reconstructions of a plot over time, establishing the impact of ice storm damage on forest canopy structure, and characterizing eastern hemlock (Tsuga canadensis) canopy health affected by an invasive insect, the hemlock woolly adelgid (Adelges tsugae). Efforts such as those deployed at HF are demonstrating the power of TLS as a tool for monitoring ecological dynamics, identifying emerging forest health issues, measuring forest biomass and capturing ecological data relevant to other disciplines. This paper highlights various aspects of the ForestGEO plot that are important to current TLS work, the potential for exchange between forest ecology and TLS, and emphasizes the strength of combining TLS data with long-term ecological field data to create emerging opportunities for scientific study.

11.
Genes Brain Behav ; 16(6): 592-600, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28296079

RESUMO

MAGEL2 is one of five protein-coding, maternally imprinted, paternally expressed genes in the Prader-Willi syndrome (PWS)-critical domain on chromosome 15q11-q13. Truncating pathogenic variants of MAGEL2 cause Schaaf-Yang syndrome (SHFYNG) (OMIM #615547), a neurodevelopmental disorder related to PWS. Affected individuals manifest a spectrum of neurocognitive and behavioral phenotypes, including intellectual disability and autism spectrum disorder (ASD). Magel2 knockout mice carrying a maternally inherited, imprinted wild-type (WT) allele and a paternally inherited Magel2-lacZ knock-in allele, which abolishes endogenous Magel2 gene function, exhibit several features reminiscent of the human Prader-Willi phenotypes, including neonatal growth retardation, excessive weight gain after weaning and increased adiposity in adulthood. They were shown to have altered circadian rhythm, reduced motor activity and reduced fertility. An extensive assessment for autism-like behaviors in this mouse model was warranted, because of the high prevalence of ASD in human patients. The behavior of Magel2 knockout mice and their WT littermates were assayed via open field, elevated plus maze, tube, three-chamber and partition tests. Our studies confirm decreased horizontal activity of male and female mice and increased vertical activity of females, in the open field. Both sexes spent more time in the open arm of the elevated plus maze, suggestive of reductions in anxiety. Both sexes displayed a lack of preference for social novelty, via a lack of discrimination between known and novel partners in the partition test. The in-depth investigation of behavioral profiles caused by Magel2 loss-of-function helps to elucidate the etiology of behavioral phenotypes both for SHFYNG and PWS in general.


Assuntos
Antígenos de Neoplasias/genética , Comportamento Exploratório , Síndrome de Prader-Willi/genética , Proteínas/genética , Comportamento Social , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo
12.
J Autism Dev Disord ; 47(3): 549-562, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27853923

RESUMO

Chromosome 15q11q13 is among the least stable regions in the genome due to its highly complex genomic architecture. Low copy repeat elements at 15q13.3 facilitate recurrent copy number variants (CNVs), with deletions established as pathogenic and CHRNA7 implicated as a candidate gene. However, the pathogenicity of duplications of CHRNA7 is unclear, as they are found in affected probands as well as in reportedly healthy parents and unaffected control individuals. We evaluated 18 children with microduplications involving CHRNA7, identified by clinical chromosome microarray analysis (CMA). Comprehensive phenotyping revealed high prevalence of developmental delay/intellectual disability, autism spectrum disorder, and attention deficit/hyperactivity disorder. As CHRNA7 duplications are the most common CNVs identified by clinical CMA, this study provides anticipatory guidance for those involved with care of affected individuals.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Espectro Autista/genética , Variações do Número de Cópias de DNA/genética , Deficiências do Desenvolvimento/genética , Fenótipo , Receptor Nicotínico de Acetilcolina alfa7/genética , Criança , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Análise em Microsséries , Linhagem
13.
J Comp Neurol ; 353(2): 161-78, 1995 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-7538152

RESUMO

The aim of this study was to investigate the neurochemical coding of myenteric neurons in the guinea pig gastric corpus by using immunohistochemical methods. Antibodies and antisera against calbindin (CALB), calretinin (CALRET), choline acetyltransferase (ChAT), calcitonin gene-related peptide (CGRP), dopamine beta-hydroxylase (DBH), beta-endorphin (ENK), neuropeptide Y (NPY), neuron-specific enolase (NSE), nitric oxide synthase (NOS), protein gene product 9.5 (PGP), parvalbumin (PARV), serotonin (5-HT), somatostatin (SOM), substance P (SP), tyrosine hydroxylase (TH), and vasoactive intestinal peptide (VIP) were used. Double- and triple-labeling studies revealed colocalization of certain transmitters and enabled the identification of distinct subpopulations of gastric enteric neurons. NPY/VIP/NOS/ENK were present in 28% of all neurons, whereas 11% had NPY/VIP/DBH/ChAT; NOS-only neurons made up 2% of the population. The combination SP/ChAT/ENK occurred in 21% of the population, whereas SP/ChAT/ENK/CALRET and SP/CHAT/SOM/ +/- CALRET was identified in 5% and 6% of all cells, respectively. 5-HT-containing neurons comprised 2% of all cells and could be further classified by the presence of additional antigens as 5-HT/SP/(ChAT) or 5-HT/VIP/(ChAT). Approximately 21% of all neurons contained only ChAT with no additional antigen present and are referred to as ChAT/-. Gastric myenteric ganglion cells were not immunoreactive for CALB, PARV, CGRP, or TH. The results of this study indicate that gastric myenteric neurons can be characterized on the basis of different chemical coding. Neurochemical coding of corpus myenteric neurons revealed some similarities and significant differences in comparison with other regions of the gut. These differences might reflect adaptation of enteric nerves according to regional specialization and the distinct functions of the proximal stomach as a gastric reservoir.


Assuntos
Cobaias/metabolismo , Plexo Mientérico/química , Neurônios/química , Estômago/inervação , Animais , Epitopos , Feminino , Cobaias/anatomia & histologia , Imuno-Histoquímica , Intestino Delgado/inervação , Masculino , Plexo Mientérico/citologia , Neurotransmissores/análise
14.
J Endocrinol ; 214(3): 389-98, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22739211

RESUMO

Curcumin (diferuloylmethane), a polyphenolic compound derived from the spice plant Curcuma longa, displays multiple actions on solid tumours including anti-angiogenic effects. Here we have studied in rodent and human pituitary tumour cells the influence of curcumin on the production of hypoxia inducible factor 1α (HIF1A) and vascular endothelial growth factor A (VEGFA), two key components involved in tumour neovascularisation through angiogenesis. Curcumin dose-dependently inhibited basal VEGFA secretion in corticotroph AtT20 mouse and lactosomatotroph GH3 rat pituitary tumour cells as well as in all human pituitary adenoma cell cultures (n=32) studied. Under hypoxia-mimicking conditions (CoCl(2) treatment) in AtT20 and GH3 cells as well as in all human pituitary adenoma cell cultures (n=8) studied, curcumin strongly suppressed the induction of mRNA synthesis and protein production of HIF1A, the regulated subunit of the hypoxia-induced transcription factor HIF1. Curcumin also blocked hypoxia-induced mRNA synthesis and secretion of VEGFA in GH3 cells and in all human pituitary adenoma cell cultures investigated (n=18). Thus, curcumin may inhibit pituitary adenoma progression not only through previously demonstrated anti-proliferative and pro-apoptotic actions but also by its suppressive effects on pituitary tumour neovascularisation.


Assuntos
Adenoma/tratamento farmacológico , Curcumina/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neoplasias Hipofisárias/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adenoma/irrigação sanguínea , Adenoma/metabolismo , Animais , Antineoplásicos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Corticotrofos/citologia , Corticotrofos/efeitos dos fármacos , Corticotrofos/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Lactotrofos/citologia , Lactotrofos/efeitos dos fármacos , Lactotrofos/metabolismo , Camundongos , Neoplasias Hipofisárias/irrigação sanguínea , Neoplasias Hipofisárias/metabolismo , RNA Mensageiro/metabolismo , Ratos , Somatotrofos/citologia , Somatotrofos/efeitos dos fármacos , Somatotrofos/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética
16.
Endocr Relat Cancer ; 16(4): 1339-50, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19726538

RESUMO

Curcumin (diferuloylmethane) is the active ingredient of the spice plant Curcuma longa and has been shown to act anti-tumorigenic in different types of tumours. Therefore, we have studied its effect in pituitary tumour cell lines and adenomas. Proliferation of lactosomatotroph GH3 and somatotroph MtT/S rat pituitary cells as well as of corticotroph AtT20 mouse pituitary cells was inhibited by curcumin in monolayer cell culture and in colony formation assay in soft agar. Fluorescence-activated cell sorting (FACS) analysis demonstrated curcumin-induced cell cycle arrest at G2/M. Analysis of cell cycle proteins by immunoblotting showed reduction in cyclin D(1), cyclin-dependent kinase 4 and no change in p27(kip). FACS analysis with Annexin V-FITC/7-aminoactinomycin D staining demonstrated curcumin-induced early apoptosis after 3, 6, 12 and 24 h treatment and nearly no necrosis. Induction of DNA fragmentation, reduction of Bcl-2 and enhancement of cleaved caspase-3 further confirmed induction of apoptosis by curcumin. Growth of GH3 tumours in athymic nude mice was suppressed by curcumin in vivo. In endocrine pituitary tumour cell lines, GH, ACTH and prolactin production were inhibited by curcumin. Studies in 25 human pituitary adenoma cell cultures have confirmed the anti-tumorigenic and hormone-suppressive effects of curcumin. Altogether, the results described in this report suggest this natural compound as a good candidate for therapeutic use on pituitary tumours.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Hormônios Hipofisários/metabolismo , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/patologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Citometria de Fluxo , Humanos , Masculino , Camundongos , Camundongos Nus , Hormônios Hipofisários/antagonistas & inibidores , Neoplasias Hipofisárias/metabolismo , Ratos
17.
Am J Physiol ; 269(2 Pt 1): G186-95, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7544534

RESUMO

The aim of this study was to investigate the organization of myenteric circuits in the guinea pig stomach. Intracellular neurobiotin injections followed by choline acetyltransferase (ChAT) immunohistochemistry and NADPH-diaphorase reaction were used to identify projections of cholinergic and nitroxidergic neurons. Neurons were classified as motor neurons based on varicose endings in the muscle or the occurrence of retraction bulbs, as nonmotor neurons if varicose endings terminated onto other ganglion cells, or as multitargeted neurons. ChAT-positive cells are composed of 64% motor, 27% nonmotor, and 9% multitargeted neurons. The percentages for NADPH-reactive motor, nonmotor, and multitargeted neurons were 57, 39, and 4%, respectively. The majority of ChAT-positive motor (81%) and nonmotor neurons (85%) had ascending projections. In contrast, the majority of NADPH-reactive motor (86%) and nonmotor neurons (86%) had descending projections. Cell bodies of ascending neurons were smaller in size than the descending neurons. The results indicate that ChAT- and NADPH-neurons in the stomach have preferred projections, the former being primarily ascending, the latter mainly descending neurons. This suggests the existence of a basic circuit for polarized reflexes in the myenteric plexus of the stomach, which might mediate descending relaxation and ascending excitation.


Assuntos
Aminoácido Oxirredutases/metabolismo , Plexo Mientérico/fisiologia , Neurônios/fisiologia , Sistema Nervoso Parassimpático/fisiologia , Estômago/inervação , Transmissão Sináptica , Animais , Eletrofisiologia , Cobaias , Plexo Mientérico/citologia , Neurônios/citologia , Óxido Nítrico Sintase , Oxirredução , Sistema Nervoso Parassimpático/citologia
18.
Int J Clin Monit Comput ; 13(2): 81-4, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8912021

RESUMO

Alarms in the operating room remain a major source of annoyance and confusion. A previous study by Kestin et al. utilized a specific combination of distinct, separate monitors in 50 pediatric patients. He reported a mean of 10 alarms per case with a mean frequency of one alarm every 4.5 minutes. The alarms were classified as spurious (75%), change outside the alarm limits (22%), or patient risk (3%). We performed a similar study with 50 adult patients under general anesthesia with default alarm settings on an integrated monitor, (Cardiocap, Datex, Helsinki). In our study, the number of alarms averaged 3 per case with a mean frequency of one every 34 minutes. Spurious alarms (those caused by electrocautery, accidental patient movement, or other non-physiological reasons) represented only 24% of all alarms. Those alarms sounding that were outside the limits occurred at a rate of 53%, and those that were considered patient risks occurred at a rate of 23%. Of the alarms, 67% occurred during the beginning and end of anesthesia. The end-tidal carbon dioxide accounted for 42% of the alarms, mostly during intubation and extubation. Suggestions are made for further improvement in alarm systems.


Assuntos
Anestesiologia/instrumentação , Monitorização Intraoperatória/instrumentação , Integração de Sistemas , Adulto , Falha de Equipamento , Humanos
19.
Am J Physiol ; 265(5 Pt 1): G1005-9, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8238509

RESUMO

Several different monoclonal and polyclonal antibodies to choline acetyltransferase (ChAT) were screened to identify effective antibodies for immunocytochemical marking of cholinergic neurons in the enteric nervous system. Excellent immunohistochemical results were obtained with two of the antibodies in the myenteric plexus of the guinea pig stomach and small intestine. One was a mouse monoclonal antibody designated B3.9B3, and the second was a rabbit polyclonal antibody referred to as Peptide 3. Both antibodies clearly stained neuronal cell bodies as well as nerve fibers to the muscle layers and fibers encircling stained and unstained cell bodies. Cell counts indicated that approximately 64% (21.0 +/- 8.6 cells/ganglion) of gastric myenteric neurons are ChAT positive. Pelvic ganglia and the inferior mesenteric ganglia were examined as controls. Strong labeling of the majority of neurons was found in the pelvic ganglia, whereas few immunoreactive cells were apparent in the predominantly noradrenergic inferior mesenteric ganglion. Lack of effective antibodies to enteric neuronal ChAT has hampered progress in the study of the neurophysiology of cholinergic neurons in the digestive tract. Application of the B3.9B3 and Peptide 3 antibodies now promises to facilitate investigation of this important subset of enteric neurons.


Assuntos
Colina O-Acetiltransferase/análise , Sistema Digestório/inervação , Músculo Liso/inervação , Plexo Mientérico/citologia , Animais , Anticorpos , Anticorpos Monoclonais , Biomarcadores/análise , Sistema Digestório/citologia , Cobaias , Imuno-Histoquímica/métodos , Músculo Liso/citologia , Plexo Mientérico/enzimologia , Fibras Nervosas/ultraestrutura , Fosfopiruvato Hidratase/análise
20.
J Neurosci ; 17(20): 8009-17, 1997 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9315919

RESUMO

The enteric nervous system coordinates various gut functions. Functional studies suggested that neurotransmitters and neuromodulators, one of the most prominent among them being 5-HT, may act through a specific modulation of ascending and descending enteric pathways. However, it is still mostly unknown how particular components of enteric reflex circuits are controlled. This report describes experiments aimed at identifying a differential activation of enteric pathways by 5-HT. Electrophysiological and immunohistochemical methods were combined to investigate the projection pattern and the transmitter phenotype of 5-HT-sensitive gastric myenteric neurons. Of 294 intracellularly labeled neurons, 60.5% showed responses mediated via 5-HT3 receptors, 11.3% were 5-HT1P-responsive, 3.7% exhibited both 5-HT3 and 5-HT1P receptor-mediated depolarization, and 24.5% were not responding to 5-HT. The 5-HT3-responsive cells were mainly cholinergic (79%) and had ascending projections, whereas the 5-HT1P-responsive cells had primarily descending projections and were nitrergic (67%). Substance P-positive neurons were cholinergic; most of the cells (75%) exhibited 5-HT3 mediated responses and had ascending projections. Muscle strip recordings supported the functional significance of the differential location of 5-HT receptor subtypes. Thus, contractile responses of gastric circular muscle strips were dose-dependently increased by a 5-HT3 and decreased by a 5-HT1P agonist. Results indicated that excitatory ascending enteric pathways consisting of cholinergic, substance Pergic neurons were activated by 5-HT3 receptors, whereas 5-HT1P receptors were involved in activation of inhibitory descending pathways using nitrergic neurons. This suggested that different effects of 5-HT on gastric functions are related to specific activation of receptors located on different subsets of enteric neurons.


Assuntos
Plexo Mientérico/fisiologia , Neurônios/fisiologia , Receptores de Serotonina/fisiologia , Estômago/inervação , Transmissão Sináptica/fisiologia , Animais , Feminino , Motilidade Gastrointestinal/efeitos dos fármacos , Cobaias , Masculino , Plexo Mientérico/citologia , Plexo Mientérico/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia
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