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1.
Mol Psychiatry ; 23(1): 36-47, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29203847

RESUMO

A great deal of interest in psychiatric research is currently centered upon the pathogenic role of inflammatory processes. Positron emission tomography (PET) using radiolabeled ligands selective for the 18 kDa translocator protein (TSPO) has become the most widely used technique to assess putative neuroimmune abnormalities in vivo. Originally used to detect discrete neurotoxic damages, TSPO has generally turned into a biomarker of 'neuroinflammation' or 'microglial activation'. Psychiatric research has mostly accepted these denotations of TSPO, even if they may be inadequate and misleading under many pathological conditions. A reliable and neurobiologically meaningful diagnosis of 'neuroinflammation' or 'microglial activation' is unlikely to be achieved by the sole use of TSPO PET imaging. It is also very likely that the pathological meanings of altered TSPO binding or expression are disease-specific, and therefore, not easily generalizable across different neuropathologies or inflammatory conditions. This difficulty is intricately linked to the varying (and still ill-defined) physiological functions and cellular expression patterns of TSPO in health and disease. While altered TSPO binding or expression may indeed mirror ongoing neuroinflammatory processes in some cases, it may reflect other pathophysiological processes such as abnormalities in cell metabolism, energy production and oxidative stress in others. Hence, the increasing popularity of TSPO PET imaging has paradoxically introduced substantial uncertainty regarding the nature and meaning of neuroinflammatory processes and microglial activation in psychiatry, and likely in other neuropathological conditions as well. The ambiguity of conceiving TSPO simply as a biomarker of 'neuroinflammation' or 'microglial activation' calls for alternative interpretations and complimentary approaches. Without the latter, the ongoing scientific efforts and excitement surrounding the role of the neuroimmune system in psychiatry may not turn into therapeutic hope for affected individuals.


Assuntos
Encefalite/etiologia , Encefalite/metabolismo , Transtornos Mentais/complicações , Receptores de GABA/metabolismo , Animais , Biomarcadores/metabolismo , Encefalite/diagnóstico por imagem , Humanos , Transtornos Mentais/diagnóstico por imagem , Modelos Moleculares , Tomografia por Emissão de Pósitrons
2.
Mol Psychiatry ; 23(2): 323-334, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28093569

RESUMO

Positron emission tomography (PET) imaging with radiotracers that target translocator protein 18 kDa (TSPO) has become a popular approach to assess putative neuroinflammatory processes and associated microglia activation in psychotic illnesses. It remains unclear, however, whether TSPO imaging can accurately capture low-grade inflammatory processes such as those present in schizophrenia and related disorders. Therefore, we evaluated the validity of TSPO as a disease-relevant marker of inflammation using a translational approach, which combined neurodevelopmental and neurodegenerative mouse models with PET imaging in patients with recent-onset schizophrenia and matched controls. Using an infection-mediated neurodevelopmental mouse model, we show that schizophrenia-relevant behavioral abnormalities and increased inflammatory cytokine expression are associated with reduced prefrontal TSPO levels. On the other hand, TSPO was markedly upregulated in a mouse model of acute neurodegeneration and reactive gliosis, which was induced by intrahippocampal injection of kainic acid. In both models, the changes in TSPO levels were not restricted to microglia but emerged in various cell types, including microglia, astrocytes and vascular endothelial cells. Human PET imaging using the second-generation TSPO radiotracer [11C]DPA-713 revealed a strong trend towards reduced TSPO binding in the middle frontal gyrus of patients with recent-onset schizophrenia, who were previously shown to display increased levels of inflammatory cytokines in peripheral and central tissues. Together, our findings challenge the common assumption that central low-grade inflammation in schizophrenia is mirrored by increased TSPO expression or ligand binding. Our study further underscores the need to interpret altered TSPO binding in schizophrenia with caution, especially when measures of TSPO are not complemented with other markers of inflammation. Unless more selective microglial markers are available for PET imaging, quantification of cytokines and other inflammatory biomarkers, along with their molecular signaling pathways, may be more accurate in attempts to characterize inflammatory profiles in schizophrenia and other mental disorders that lack robust reactive gliosis.


Assuntos
Receptores de GABA/metabolismo , Esquizofrenia/metabolismo , Adulto , Animais , Astrócitos/metabolismo , Biomarcadores/sangue , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Neuroimunomodulação/fisiologia , Tomografia por Emissão de Pósitrons/métodos , Receptores de GABA/análise , Esquizofrenia/diagnóstico por imagem
3.
Ann Behav Med ; 46(3): 369-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23813320

RESUMO

BACKGROUND: The Weight Loss Maintenance Trial tested strategies for maintenance of weight loss. Personal contact was superior to interactive technology and self-directed conditions. PURPOSE: We aimed to identify behavioral mediators of the superior effect of personal contact vs. interactive technology and of personal contact vs. self-directed arms. METHODS: Overweight/obese adults at risk for cardiovascular disease (n = 1,032) who lost at least 4 kg were randomized to personal contact, interactive technology, or self-directed. After 30 months, 880 participants had data on weight and behavioral strategies. RESULTS: Reported increase of intake of fruits and vegetables and physical activity and more frequent self-weighing met criteria as mediators of the better outcome of personal contact vs. interactive technology. Increased intake of fruits and vegetables, more frequent self-weighing, and decreased dessert consumption were mediators of the difference between personal contact vs. self-directed. CONCLUSION: Inducing changes in the identified behaviors might yield better outcomes in future weight loss maintenance trials.


Assuntos
Obesidade/psicologia , Obesidade/terapia , Sobrepeso/psicologia , Sobrepeso/terapia , Programas de Redução de Peso , Aconselhamento , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Autocuidado/psicologia , Terapia Assistida por Computador , Resultado do Tratamento
4.
Qual Life Res ; 22(9): 2389-98, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23515902

RESUMO

PURPOSE: To evaluate effects of two behavioral weight-loss interventions (in-person, remote) on health-related quality of life (HRQOL) compared to a control intervention. METHODS: Four hundred and fifty-one obese US adults with at least one cardiovascular risk factor completed five measures of HRQOL and depression: MOS SF-12 physical component summary (PCS) and mental component summary; EuroQoL-5 dimensions single index and visual analog scale; PHQ-8 depression symptoms; and PSQI sleep quality scores at baseline and 6 and 24 months after randomization. Change in each outcome was analyzed using outcome-specific mixed-effects models controlling for participant demographic characteristics. RESULTS: PCS-12 scores over 24 months improved more among participants in the in-person active intervention arm than among control arm participants (P < 0.05, ES = 0.21); there were no other statistically significant treatment arm differences in HRQOL change. Greater weight loss was associated with improvements in most outcomes (P < 0.05 to < 0.0001). CONCLUSIONS: Participants in the in-person active intervention improved more in physical function HRQOL than participants in the control arm did. Greater weight loss during the study was associated with greater improvement in all PRO except for sleep quality, suggesting that weight loss is a key factor in improving HRQOL.


Assuntos
Terapia Comportamental , Obesidade/terapia , Qualidade de Vida , Redução de Peso , Adulto , Depressão , Feminino , Nível de Saúde , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Obesidade/psicologia , Medição da Dor , Transtornos do Sono-Vigília , Resultado do Tratamento
5.
Can J Public Health ; 103(2): 132-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22530537

RESUMO

OBJECTIVES: Research in the United States has found a higher likelihood of smoking among lesbian, gay and bisexual people compared to the general population. However, the smoking prevalence of these subpopulations in Canada is not well documented. The objective of this study was to determine the prevalence of smoking among the LGBTTQ subpopulations in Toronto, Ontario. METHODS: A self-report questionnaire was administered from April to July 2006 to a convenience sample of lesbian, gay, bisexual, transsexual, transgender and queer (LGBTTQ) community members in Toronto, Ontario. Items measured included: past and current smoking behaviour, sexual orientation, gender identity, age and residential area. RESULTS: In total, 3,140 LGBTTQ community members completed the Toronto Rainbow Tobacco Survey (TRTS). Overall, 36% of LGBTTQ participants reported current smoking, 25% were former smokers and 39% had never smoked. The smoking prevalence rates ranged from 24% to 45% across the different sexual orientation and gender identity groups of the sample, with bisexual women and bisexual men reporting the highest smoking rate at 45%. The study also reports the first known smoking prevalence rate for gender queer people at 44%. Younger LGBTTQ participants reported even higher smoking rates. CONCLUSION: This study corroborates prior research done in other jurisdictions by finding similar and higher smoking rates among Toronto's LGBTTQ subpopulations compared to the "mainstream" population. The relatively higher rates among LGBTTQ youth, bisexual and gender queer people have implications for targeted awareness and cessation initiatives. Need for future research is discussed.


Assuntos
Bissexualidade , Homossexualidade Feminina , Homossexualidade Masculina , Fumar/epidemiologia , Transexualidade , Adulto , Feminino , Humanos , Masculino , Ontário/epidemiologia , Prevalência , Inquéritos e Questionários
6.
Obes Sci Pract ; 6(5): 484-493, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33082990

RESUMO

INTRODUCTION: Gestational weight gain (GWG) and postpartum weight retention (PPWR) are significant, potentially modifiable, contributors to women's future weight and health trajectories. There is a need for feasible and patient-centered (i.e., convenient, remotely-delivered, technology-enhanced, and accessible through the prenatal care setting) behavioural interventions that limit GWG and PPWR. This study tests the feasibility and acceptability of a remotely-delivered behavioural health coaching intervention to limit gestational weight gain and postpartum weight retention. METHODS: Pregnant women (11-16 weeks gestation) were recruited from two prenatal clinics and randomized to the active intervention or health education comparison group. Completion of the program was monitored and perceived helpfulness was rated (0-100). RESULTS: Twenty-six women were randomized (n = 13 per arm; mean age = 31.6 years, SD = 3.6; mean BMI = 26.7 kg/m2, SD = 7.4). Participants completed a median of 18 coaching calls and 16/19 learning activities during pregnancy, and a median of 6 calls and 5/6 learning activities postpartum. They logged weights at least once/week for a median of 36/38 expected weeks and tracked daily calories and exercise for a median of 154/266 days and 72/266 days, respectively. Median (Q1, Q3) helpfulness ratings of the program during pregnancy were 80 (64, 91) and 62 (50, 81) postpartum; helpfulness ratings of coaching calls were 85 (58, 98). At 37 weeks gestation, 77% of participants achieved IOM weight gain recommendations compared to 54% in the comparison group. CONCLUSIONS: This study provides evidence for the feasibility and acceptability of a remotely-delivered behavioural weight control intervention in pregnancy and postpartum.

8.
Sci Total Environ ; 691: 1328-1352, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466212

RESUMO

Frameworks for limiting ecosystem exposure to excess nutrients and acidity require accurate and complete deposition budgets of reactive nitrogen (Nr). While much progress has been made in developing total Nr deposition budgets for the U.S., current budgets remain limited by key data and knowledge gaps. Analysis of National Atmospheric Deposition Program Total Deposition (NADP/TDep) data illustrates several aspects of current Nr deposition that motivate additional research. Averaged across the continental U.S., dry deposition contributes slightly more (55%) to total deposition than wet deposition and is the dominant process (>90%) over broad areas of the Southwest and other arid regions of the West. Lack of dry deposition measurements imposes a reliance on models, resulting in a much higher degree of uncertainty relative to wet deposition which is routinely measured. As nitrogen oxide (NOx) emissions continue to decline, reduced forms of inorganic nitrogen (NHx = NH3 + NH4+) now contribute >50% of total Nr deposition over large areas of the U.S. Expanded monitoring and additional process-level research are needed to better understand NHx deposition, its contribution to total Nr deposition budgets, and the processes by which reduced N deposits to ecosystems. Urban and suburban areas are hotspots where routine monitoring of oxidized and reduced Nr deposition is needed. Finally, deposition budgets have incomplete information about the speciation of atmospheric nitrogen; monitoring networks do not capture important forms of Nr such as organic nitrogen. Building on these themes, we detail the state of the science of Nr deposition budgets in the U.S. and highlight research priorities to improve deposition budgets in terms of monitoring and flux measurements, leaf- to regional-scale modeling, source apportionment, and characterization of deposition trends and patterns.

9.
Chem Sci ; 8(2): 1146-1151, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28451255

RESUMO

Controlling the regioregularity among the structural units of narrow bandgap conjugated polymer backbones has led to improvements in optoelectronic properties, for example in the mobilities observed in field effect transistor devices. To investigate how the regioregularity affects quantities relevant to hole transport, regioregular and regiorandom oligomers representative of polymeric structures were studied using density functional theory. Several structural and electronic characteristics of the oligomers were compared, including chain planarity, cation spin density, excess charges on molecular units and internal reorganizational energy. The main difference between the regioregular and regiorandom oligomers is found to be the conjugated backbone planarity, while the reorganizational energies calculated are quite similar across the molecular family. This work constitutes the first step on understanding the complex interplay of atomistic changes and an oligomer backbone structure toward modeling the charge transport properties.

10.
Transl Psychiatry ; 6: e777, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27070405

RESUMO

Several lines of evidence suggest aberrant immune response in schizophrenia, including elevated levels of cytokines. These cytokines are thought to be produced by activated microglia, the innate immune cells of the central nervous system. However, increase in translocator protein 18 kDa (TSPO), a marker of activated glia, has not been found in patients with chronic schizophrenia using second-generation radiotracers and positron emission tomography (PET)-based neuroimaging. In this study we focused on patients with recent onset of schizophrenia (within 5 years of diagnosis). Quantified levels of TSPO in the cortical and subcortical brain regions using the PET-based radiotracer [(11)C]DPA-713 were compared between the patients and healthy controls. Markers of inflammation, including interleukin 6 (IL-6), were assessed in the plasma and cerebrospinal fluid (CSF) in these participants. We observed no significant change in the binding of [(11)C]DPA-713 to TSPO in 12 patients with recent onset of schizophrenia compared with 14 controls. Nevertheless, the patients with recent onset of schizophrenia showed a significant increase in IL-6 in both plasma (P<0.001) and CSF (P=0.02). The CSF levels of IL-6 were significantly correlated with the levels of IL-6 in plasma within the total study population (P<0.001) and in patients with recent onset of schizophrenia alone (P=0.03). Our results suggest that increased levels of IL-6 may occur in the absence of changed TSPO PET signal in the brains of medicated patients with recent onset of schizophrenia. Future development of PET-based radiotracers targeting alternative markers of glial activation and immune response may be needed to capture the inflammatory signature present in the brains of patients with early-stage disease.


Assuntos
Encéfalo/metabolismo , Inflamação/sangue , Inflamação/líquido cefalorraquidiano , Tomografia por Emissão de Pósitrons/métodos , Esquizofrenia/sangue , Esquizofrenia/líquido cefalorraquidiano , Acetamidas , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Feminino , Humanos , Inflamação/diagnóstico por imagem , Masculino , Pirazóis , Pirimidinas , Esquizofrenia/diagnóstico por imagem , Adulto Jovem
11.
Curr Mol Med ; 15(2): 176-83, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25732147

RESUMO

Aberrant function of glutamatergic pathways is likely to underlie the pathology of schizophrenia. Evidence of oxidative stress in the disease pathology has also been reported. N-Acetylaspartate (NAA) is metabolically linked to both cascades and may be a key marker in exploring the interconnection of glutamatergic pathways and oxidative stress. Several studies have reported positive correlation between the levels of NAA and Glx (the sum of glutamate and glutamine) in several brain regions in healthy subjects, by using proton magnetic resonance spectroscopy ([(1)H]MRS). Interestingly, one research group recently reported decoupling of the relationship between NAA and Glx in the hippocampus of patients with schizophrenia. Here we report levels of NAA and Glx measured using [(1)H]MRS, relative to the level of creatine (Cr) as an internal control. The dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC) in 25 patients with schizophrenia and 17 matched healthy controls were studied. In DLPFC, NAA/Cr and Glx/Cr were significantly positively correlated in healthy controls after correction for the effect of age and smoking status and after correction for multiple comparisons (r= 0.627, P= 0.017). However, in patients with schizophrenia, the positive correlation between NAA/Cr and Glx/Cr was not observed even after correcting for these two variables (r= -0.330, P= 0.124). Positive correlation between NAA/Cr and Glx/Cr was not observed in the ACC in both groups. Decoupling of NAA and Glx in the DLPFC may reflect the interconnection of glutamatergic pathways and oxidative stress in the pathology of schizophrenia, and may possibly be a biomarker of the disease.


Assuntos
Ácido Aspártico/análogos & derivados , Ácido Glutâmico/metabolismo , Giro do Cíngulo/metabolismo , Córtex Pré-Frontal/metabolismo , Esquizofrenia/diagnóstico , Esquizofrenia/metabolismo , Adulto , Ácido Aspártico/metabolismo , Estudos de Casos e Controles , Creatina/metabolismo , Feminino , Glutamina/metabolismo , Giro do Cíngulo/patologia , Humanos , Masculino , Testes Neuropsicológicos , Estresse Oxidativo , Córtex Pré-Frontal/patologia , Espectroscopia de Prótons por Ressonância Magnética , Esquizofrenia/patologia
12.
Obes Sci Pract ; 1(1): 23-32, 2015 10.
Artigo em Inglês | MEDLINE | ID: mdl-27668085

RESUMO

BACKGROUND: Behavioural weight loss programs are effective first-line treatments for obesity and are recommended by the US Preventive Services Task Force. Gaining an understanding of intervention components that are found helpful by different demographic groups can improve tailoring of weight loss programs. This paper examined the perceived helpfulness of different weight loss program components. METHODS: Participants (n = 236) from the active intervention conditions of the Practice-based Opportunities for Weight Reduction (POWER) Hopkins Trial rated the helpfulness of 15 different components of a multicomponent behavioural weight loss program at 24-month follow-up. These ratings were examined in relation to demographic variables, treatment arm and weight loss success. RESULTS: The components most frequently identified as helpful were individual telephone sessions (88%), tracking weight online (81%) and coach review of tracking (81%). The component least frequently rated as helpful was the primary care providers' general involvement (50%). Groups such as older adults, Blacks and those with lower education levels more frequently reported intervention components as helpful compared with their counterparts. DISCUSSION: Weight loss coaching delivered telephonically with web support was well received. Findings support the use of remote behavioural interventions for a wide variety of individuals.

13.
Clin Obes ; 5(6): 342-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26486256

RESUMO

This paper examined the psychosocial predictors of weight loss among race and sex subgroups. Analyses included overweight and obese participants from the PREMIER study, a previously published randomized trial that examined the effects of two multi-component lifestyle interventions on blood pressure among pre-hypertensive and stage 1 hypertensive adults. Both intervention conditions received behavioural recommendations for weight loss and group sessions. Weight and psychosocial measures of self-efficacy and social support for diet and exercise were assessed at baseline and at 6 months. There were 157 African-American (AA) women, 46 AA men, 203 non-AA women and 182 non-AA men with an average age of 50 years and average body mass index of 34 at baseline. Multiple predictor regression models were performed individually by race and sex subgroup. Among AA women, increases in diet self-efficacy were associated with weight loss. Among AA men, increases in diet-related social support and self-efficacy, along with increases in family support to exercise, were associated with weight loss (all Ps <0.05). Among non-AA women, increases in friends' support to exercise and exercise-related self-efficacy were associated with weight loss, and among non-AA men only increases in diet self-efficacy were associated with weight loss (all Ps <0.05). These results emphasize the need for targeted interventions based on race and sex to optimize the impact of lifestyle-based weight loss programmes.


Assuntos
Dietoterapia , Exercício Físico , Comportamentos Relacionados com a Saúde/etnologia , Grupos Raciais/psicologia , Autoeficácia , Apoio Social , Redução de Peso/etnologia , Adulto , Negro ou Afro-Americano/psicologia , Pressão Sanguínea , Feminino , Humanos , Hipertensão/terapia , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Obesidade/psicologia , Sobrepeso/psicologia , Fatores Sexuais , Estados Unidos , População Branca/psicologia
14.
J Clin Endocrinol Metab ; 75(5): 1318-25, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1358910

RESUMO

Glycoprotein hormone-producing (GPH) pituitary adenomas represent approximately 25% of all pituitary tumors. Elevated serum levels of intact GPHs or their free alpha- and beta-subunits have been demonstrated in patients with such tumors, and isolated hypersecretion of alpha-subunit has been reported to occur in 7% of patients. Somatostatin has been shown to decrease GPH subunit levels in cultured adenoma cells in vitro, and somatostatin receptors have been identified on the cell membranes of these tumors. We, therefore, investigated the effect of chronic somatostatin analog administration on hormone production and tumor size in six patients with GPH-producing macroadenomas and elevated serum alpha-subunit levels. Patients initially received native somatostatin as an iv 250-micrograms bolus at 0800 h, followed by a constant infusion of 2 mg over 4 h, and serum alpha-subunit concentrations were measured at 30-min intervals after baseline sampling for a total of 9 h. Patients then received a somatostatin analog, octreotide (100 micrograms, twice daily, sc) for 8 weeks. Serum alpha-subunit levels were determined weekly at 30-min intervals before and for 4 h after the 0800 h octreotide dose. Pituitary magnetic resonance imaging scans and visual field testing were assessed before and after the study. During the 4-h somatostatin infusion, four patients had a significant decrease in alpha-subunit levels (P < 0.05). During the 8-week chronic octreotide administration period, two patients had significant decreases in alpha-subunit levels of 34.6% and 26.7% (P = 0.03 and 0.01, respectively). One of these two patients had a small reduction in tumor size. Two patients whose serum alpha-subunit level did not significantly change while receiving octreotide had a reduction in tumor size or definite improvement in visual field abnormalities. Three patients received a maximum octreotide dose of 250 micrograms, three times daily. In one patient, there was a significant decrease in alpha-subunit levels by 45% (P = 0.0001) in association with a marked improvement in visual field abnormalities. In another such patient, continued administration of octreotide to a maximum dose of 250 micrograms, three times daily, was associated with a marked reduction in tumor size. Of the four patients who demonstrated significant decreases in alpha-subunit concentrations during the initial somatostatin infusion, three patients had a significant reduction in alpha-subunit levels while receiving octreotide. One patient who did not have a decrease in alpha-subunit levels during the somatostatin infusion demonstrated a small decrease in tumor size during higher dose octreotide treatment.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Adenoma/metabolismo , Glicoproteínas/biossíntese , Hormônios/biossíntese , Octreotida/uso terapêutico , Neoplasias Hipofisárias/metabolismo , Adenoma/diagnóstico , Adulto , Idoso , Feminino , Glicoproteínas/química , Hormônios/química , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/diagnóstico , Somatostatina/farmacologia , Campos Visuais/efeitos dos fármacos
15.
J Comp Neurol ; 210(1): 10-29, 1982 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-7130467

RESUMO

Do structures exist within the embryonic central nervous system that guide axons across the midline during development of the great cerebral commissures (corpus callosum, anterior commissure)? With the use of serial section and reconstructive computer graphic techniques we have found that during normal ontogeny of the mouse forebrain and before the arrival of the pioneer fibers of the corpus callosum at the midline, a population of primitive glial cells migrates medially (through the fused walls of the dorsal septum) from the ependymal zones of each hemisphere. At the midline, and well rostral to the lamina terminalis, these cells unite to form a bridgelike structure or "sling" suspended below the longitudinal cerebral fissure. The first callosal axons grow along the surface of this cellular bridge as they travel toward the contralateral side of the brain. The "sling" disappears neonatally. The fibers of the anterior commissure grow within the lamina terminalis along a different type of preformed glial structure. Movement of these axons occurs through an aligned system of glial processes separated by wide extracellular spaces. Do these transient glial tissues actually provide guidance cues to the commissural axons? Analyses of three situations in which the glial "sling" is genetically or surgically impaired or nonexistent indicate that this structure does, indeed, play an essential role in the development of the corpus callosum. We have analyzed (1) the embryonic stages of a congenitally acallosal mouse mutant (strain BALB/cCF), (2) several pouch stages of a primitive acallosal marsupial, Didelphys virginiana (opossum), and (3) animals in which the "sling" had been lesioned surgically through the uterine wall in the normal embryo (strain C57BL/6J). In the acallosal mouse mutant fusion of the septal midline is delayed by about 72 hours and the "sling" does not form. Although the would-be callosal axons approach the midline on schedule, they do not cross. Instead, the callosal fibers whirl into a pair of large neuromas adjacent to the longitudinal fissure. Similarly, in the opossum, fusion of the medial septal walls and formation of the glial "sling" are also lacking. However, in this species, instead of traveling dorsally, the "callosal" axons turn ventrally and pass contralaterally by way of the anterior commissure pathway. Surgical disunion of the glial "sling" also resulted in acallosal individuals. The callosal pathology in these affected animals mimicked exactly that of the genetically lesioned mutant. Our observations suggest that many different types of oriented glial tissues exist within the embryonic neural anlage. We propose that such tissues have the ability to influence the directionality of axonal movements and, thereby, play a crucial role in establishing orderly fiber projections within the developing central nervous system.


Assuntos
Encéfalo/enzimologia , Neuroglia/fisiologia , Agenesia do Corpo Caloso , Animais , Córtex Cerebral/embriologia , Corpo Caloso/embriologia , Hipocampo/embriologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes Neurológicos/embriologia , Microscopia Eletrônica , Morfogênese , Gambás/embriologia
16.
Mol Cell Endocrinol ; 49(1): 75-86, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3030847

RESUMO

The fetal regressor Müllerian inhibiting substance (MIS), in concentrations as low as picomolar, inhibited the growth of A-431 cells and the autophosphorylation of its epidermal growth factor (EGF) receptor. The inhibition of membrane phosphorylation was due neither to the reduction of the total number of EGF receptor binding sites, nor to stimulation of intrinsic phosphates, but rather to inhibition of tyrosine kinase activity. MIS control of EGF receptor autophosphorylation by tyrosine kinase may be one mechanism by which Müllerian duct regression in the embryo and the inhibition of A-431 proliferation is initiated. In addition, MIS as an inhibitor of phosphorylation may furnish a tool to probe the role of membrane phosphorylation in growth control.


Assuntos
Receptores ErbB/metabolismo , Glicoproteínas , Inibidores do Crescimento , Proteínas Tirosina Quinases/antagonistas & inibidores , Hormônios Testiculares/farmacologia , Animais , Hormônio Antimülleriano , Bovinos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Membrana Celular/enzimologia , Fator de Crescimento Epidérmico/farmacologia , Feminino , Humanos , Masculino , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Neoplasias Vulvares
17.
Hum Pathol ; 29(1): 94-5, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9445140

RESUMO

Pathological demonstration of varicella infection in first trimester aborted tissue is reported. A 24-year-old primigravida manifested chickenpox infection about 38 days after her last menstrual period or at 24 days age of the embryo. The conceptus survived another 4 to 5 weeks. The macerated embryo and placental tissue revealed nuclear changes consistent with varicella infection. Immunohistochemical stains and electron microscopy were confirmatory.


Assuntos
Varicela/patologia , Varicela/transmissão , Morte Fetal/virologia , Herpesvirus Humano 3/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/virologia , Adulto , Antígenos Virais/análise , Vilosidades Coriônicas/ultraestrutura , Vilosidades Coriônicas/virologia , Feminino , Humanos , Microscopia Eletrônica , Gravidez , Primeiro Trimestre da Gravidez
18.
Psychiatr Genet ; 12(1): 43-7, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11901359

RESUMO

A strong genetic association between the NOTCH4 locus on chromosome 6 and schizophrenia was recently reported. Based on the data suggesting overlapping susceptibility for schizophrenia and bipolar disorder, we genotyped the polymorphic (CTG)n encoding polyleucine repeat in exon 1 of NOTCH4 in 65 pedigrees ascertained for a genetic linkage study of bipolar disorder. In addition, we analyzed a subset of our pedigrees with psychotic features at this locus. We failed to find any association between the (CTG)n NOTCH4 polymorphism and either the bipolar or the psychotic bipolar phenotype in our 65 pedigrees.


Assuntos
Transtorno Bipolar/genética , Polimorfismo Genético , Proteínas Proto-Oncogênicas/genética , Receptores de Superfície Celular , Repetições de Trinucleotídeos/genética , Sequência de Bases , Genótipo , Humanos , Complexo Principal de Histocompatibilidade , Peptídeos , Receptor Notch4 , Receptores Notch
19.
Surgery ; 114(4): 822-6; discussion 826-7, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8211700

RESUMO

BACKGROUND: Outcome for most abdominal wall defects is related to the presence or absence of additional anomalies or prematurity. In gastroschisis, outcome is almost as closely related to the severity of the inflammatory "peel" on bowel that is thought to result from direct contact with amniotic fluid. Improving eviscerated bowel quality would be expected to reduce morbidity in these patients. METHODS: From 1986 to 1991, 32 patients with the antenatal diagnosis of gastroschisis were treated. All were delivered by cesarean section; 13 surgical repairs were made immediately in the delivery room. Surgical repairs in 19 patients were made at less than 6 hours of age after transfer from the delivering hospital to the pediatric surgery center. RESULTS: Thirty percent of infants who underwent surgical repair in delivery room and 32% of infants who underwent urgent surgical repair were either premature or had significant associated anomalies. Seventy-three percent of delivery room repair group had fascial repairs compared with 37% in the transferred group. When infants more than 34-weeks' gestation without associated anomalies are compared with transferred infants, delivery room repair group underwent more frequent fascial repair (8 of 9 vs 5 of 13, p < 0.03), were extubated sooner (2.9 vs 7.4 days, p < 0.04), tolerated enteral feedings earlier (8.1 vs 22.2 days, p < 0.009), and required fewer hospital days (13.6 vs 31.3 days, p < 0.01). Eviscerated bowel of infants who underwent immediate surgical repair lacked the characteristic matted, edematous, and fibrinous coated appearance seen in transferred patients. CONCLUSIONS: Immediate delivery room repair of gastroschisis results in increased fascial repairs and earlier extubation, feeding, and hospital discharge. These benefits appear to be due to the minimal reactive peel on eviscerated bowel at birth.


Assuntos
Músculos Abdominais/anormalidades , Músculos Abdominais/cirurgia , Salas de Parto , Anormalidades Múltiplas/cirurgia , Fasciotomia , Humanos , Mortalidade Infantil , Recém-Nascido , Recém-Nascido Prematuro , Morbidade , Complicações Pós-Operatórias/mortalidade
20.
Obstet Gynecol ; 78(6): 996-1001, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1945230

RESUMO

Hypothalamic amenorrhea, a common disorder associated with abnormalities in gonadotropin pulsatility and subsequent estrogen deficiency, is usually transient, and treatment indications are unclear unless fertility is desired. To determine whether this disorder is associated with progressive bone loss, we studied 24 women with primary or secondary amenorrhea related to stress or simple weight loss, compared with 31 normal women of the same age. Amenorrheic women had significantly lower (P = .01) body fat (26.4 +/- 7.3 versus 30.6 +/- 4.7%) and higher (P = .0001) urine free cortisol levels (250 +/- 100 versus 140 +/- 50 nmol/day) than normals. Trabecular bone density in women with hypothalamic amenorrhea as assessed by spinal computed tomography was significantly (P = .001) lower than in normals (140.2 +/- 27.3 versus 175.1 +/- 24.6 mg K2HPO4/mL, respectively). Twenty of the 24 amenorrheic women had initial spinal bone density below the mean in normals, and in eight it was 2 standard deviations or more below the normal mean. Initial bone density correlated negatively with duration of amenorrhea (r = -0.489, P = .02) and positively with serum free testosterone levels (r = 0.517, P = .02). Prospective evaluation showed a decline in spinal bone density in those who were amenorrheic for fewer than 5 years. The slope of change in bone density correlated with initial weight, percent ideal body weight, and percent body fat (R2 = 0.597, P = .0003; R2 = 0.549, P = .0007; and R2 = 0.618, P = .0002, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Amenorreia/complicações , Doenças Ósseas Metabólicas/etiologia , Hipotálamo/fisiopatologia , Adulto , Amenorreia/etiologia , Amenorreia/metabolismo , Densidade Óssea , Doenças Ósseas Metabólicas/metabolismo , Feminino , Humanos , Estudos Prospectivos
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