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Amanda V. Steckert Clarissa M. Comim Francielle Mina Bruna P. Mendonça Diogo Dominguini Gabriela K. Ferreira Milena Carvalho‐Silva Júlia S. Vieira Emilio L. Streck João Quevedo Felipe Dal‐Pizzol 《Synapse (New York, N.Y.)》2013,67(11):786-793
Central nervous system (CNS) dysfunction secondary to sepsis is characterized by long‐term cognitive impairment. It was observed that oxidative damage, energetic metabolism impairment, and cytokine level alteration seen in early times in an animal model of sepsis may persist for up to 10 days and might be associated with cognitive damage. In order to understand these mechanisms, at least in part, we evaluated the effects of sepsis on cytokine levels in the cerebrospinal fluid (CSF), oxidative parameters, and energetic metabolism in the brain of rats at both 30 and 60 days after sepsis induction by cecal ligation and perforation (CLP). To this aim, male Wistar rats underwent CLP with “basic support” or were sham‐operated. Both 30 and 60 days after surgery, the CSF was collected and the animals were killed by decapitation. Then, the prefrontal cortex, hippocampus, striatum, and cortex were collected. Thirty days after surgery, an increase of IL‐6 level in the CSF; an increase in the thiobarbituric acid‐reactive species (TBARS) in prefrontal cortex and a decrease in hippocampus, striatum, and cortex; a decrease of carbonyl protein formation only in prefrontal cortex and an increase in striatum; and an increase in the complex IV activity only in hippocampus were observed. Sixty days after sepsis, an increase of TNF‐α level in the CSF; a decrease of TBARS only in hippocampus; an increase of carbonyl protein formation in striatum; and a decrease of complex I activity in prefrontal cortex, hippocampus, and striatum were observed. These findings may contribute to understanding the role of late cognitive impairment. Further studies may address how these findings interact during sepsis development and contribute to CNS dysfunction. Synapse 67:786–793, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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Mario Musella Jan Apers Karl Rheinwalt Rui Ribeiro Emilio Manno Francesco Greco Michal Čierny Marco Milone Carla Di Stefano Sahin Guler Isa Mareike Van Lessen Anabela Guerra Mauro Natale Maglio Riccardo Bonfanti Radoslava Novotna Guido Coretti Luigi Piazza 《Obesity surgery》2016,26(5):933-940
Background
A retrospective study was undertaken to define the efficacy of both mini gastric bypass or one anastomosis gastric bypass (MGB/OAGB) and sleeve gastrectomy (SG) in type 2 diabetes mellitus (T2DM) remission in morbidly obese patients (pts).Methods
Eight European centers were involved in this survey. T2DM was preoperatively diagnosed in 313/3252 pts (9.62 %). In 175/313 patients, 55.9 % underwent MGB/OAGB, while in 138/313 patients, 44.1 % received SG between January 2006 and December 2014.Results
Two hundred six out of 313 (63.7 %) pts reached 1 year of follow-up. The mean body mass index (BMI) for MGB/OAGB pts was 33.1?±?6.6, and the mean BMI for SG pts was 35.9?±?5.9 (p?<?0.001). Eighty-two out of 96 (85.4 %) MGB/OAGB pts vs. 67/110 (60.9 %) SG pts are in remission (p?<?0.001). No correlation was found in the % change vs. baseline values for hemoglobin A1c (HbA1c) and fasting plasma glucose (FPG) in relation to BMI reduction, for both MGB/OAGB or SG (ΔFPG 0.7 and ΔHbA1c 0.4 for MGB/OAGB; ΔFPG 0.7 and ΔHbA1c 0.1 for SG). At multivariate analysis, high baseline HbA1c [odds ratio (OR)?=?0.623, 95 % confidence interval (CI) 0.419–0.925, p?=?0.01], preoperative consumption of insulin or oral antidiabetic agents (OR?=?0.256, 95 % CI 0.137–0.478, p?=?<0.001), and T2DM duration >10 years (OR?=?0.752, 95 % CI 0.512–0.976, p?=?0.01) were negative predictors whereas MGB/OAGB resulted as a positive predictor (OR?=?3.888, 95 % CI 1.654–9.143, p?=?0.002) of diabetes remission.Conclusions
A significant BMI decrease and T2DM remission unrelated from weight loss were recorded for both procedures if compared to baseline values. At univariate and multivariate analyses, MGB/OAGB seems to outperform significantly SG. Four independent variables able to influence T2DM remission at 12 months have been identified.98.
Emilio A. Herrera René Alegría Marcelo Farias Farah Díaz‐López Cherie Hernández Ricardo Uauy Timothy R. H. Regnault Paola Casanello Bernardo J. Krause 《The Journal of physiology》2016,594(6):1553-1561
Key points
- Intrauterine growth restriction (IUGR) is associated with short‐ and long‐term detrimental cardiometabolic effects.
- Mice and rats are commonly used to assess IUGR, but differences in placental and fetal developmental physiology relative to those in humans highlight the need for alternative small animal IUGR models.
- We developed a guinea pig IUGR model by gradual occlusion of uterine arteries by ameroid constrictor implantation. In this model, reduced uterine blood flow was associated with IUGR, allowing in vivo assessment of fetal growth trajectory and umbilico‐placental vascular function in conscious animals.
- The intervention induces placental vascular dysfunction and remodelling, as well as altered fetal abdominal growth resulting in an asymmetric IUGR and preserved brain growth.
Abstract
Intra‐uterine growth restriction (IUGR) is associated with short and long‐term metabolic and cardiovascular alterations. Mice and rats have been extensively used to study the effects of IUGR, but there are notable differences in fetal and placental physiology relative to those of humans that argue for alternative animal models. This study proposes that gradual occlusion of uterine arteries from mid‐gestation in pregnant guinea pigs produces a novel model to better assess human IUGR. Fetal biometry and in vivo placental vascular function were followed by sonography and Doppler of control pregnant guinea pigs and sows submitted to surgical placement of ameroid constrictors in both uterine arteries (IUGR) at mid‐gestation (35 days). The ameroid constrictors induced a reduction in the fetal abdominal circumference growth rate (0.205 cm day−1) compared to control (0.241 cm day−1, P < 0.001) without affecting biparietal diameter growth. Umbilical artery pulsatility and resistance indexes at 10 and 20 days after surgery were significantly higher in IUGR animals than controls (P < 0.01). These effects were associated with a decrease in the relative luminal area of placental chorionic arteries (21.3 ± 2.2% vs. 33.2 ± 2.7%, P < 0.01) in IUGR sows at near term. Uterine artery intervention reduced fetal (∼30%), placental (∼20%) and liver (∼50%) weights (P < 0.05), with an increased brain to liver ratio (P < 0.001) relative to the control group. These data demonstrate that the ameroid constrictor implantations in uterine arteries in pregnant guinea pigs lead to placental vascular dysfunction and altered fetal growth that induces asymmetric IUGR. 相似文献99.
100.
The presence of cells or tissues from two individuals, chimeras, or the presence of cells and tissues that include the gonads,
tetragametic chimerism can be detected by the analysis of cytogenetics and analysis of polymorphic genetic markers, using
patterns of pedigree inheritance. These methodologies include determination of sex chromosomes, major histocompatibility complex
(MHC) polymorphisms and panels of short tandem repeats (STRs) that include mitochondrial DNA markers. Studies routinely involve
cases of temporal chimerism in blood transfusion, or following allotransplantation to measure the outcome of the organ, lymphopoietic
tissues or bone marrow grafts. Demonstration of persistent chimerism is usually discovered in cases of inter-sexuality due
to fusion of fraternal twins or in cases of fusion of embryos with demonstrable allogeneic monoclonality of blood which, excluded
maternity or paternity when blood alone is used as the source of DNA. In single pregnancies it is possible to produce two
kinds of microchimerism: feto-maternal and materno-fetal, but in cases of fraternal twin pregnancies it is possible to identify
three different kinds which are related to cases of vanishing twins that can be identified during pregnancy by imaging procedures;
(1) hematopoietic, (2) gonadal, and (3) freemartins when the twins have different sex and the individual born is a female
with either gonadal or both gonadal and hematopoietic tissues. Fraternal twin pregnancies can also produce fusion of embryos.
Such cases could be of different sex presenting with inter-sexuality or in same sex twins. One of such cases, the best studied,
showed evidence of chimerism and tetragametism. In this regard, the case was studied because of disputed maternity of two
of her three children. All tissues studied, except for the blood, demonstrated four genetic components but only two in her
blood of four possible showed allogeneic monoclonality consistent with the interpretation that her blood originated from one
hematopoietic stem cell. Also, microchimerism, due to traffic of cells via materno-fetal or feto-maternal has been prompted
by reports of their potential association with the development of autoimmune disorders including systemic lupus erythematosus
(SLE) and systemic sclerosis, and in allotransplantation. In addition, their relevance of chimerism in the positive and negative
selection of T cells in the thymus has not been addressed. T lymphocytes play a central role in controlling the acquired immune
response and furthermore serve as crucial effector cells through antigen specific cytotoxic activity and the production of
soluble mediators. Central tolerance is established by the repertoire selection of immature T lymphocytes in the thymus, avoiding
the generation of autoreactive T cells. Expression of chimeric antigens in the thymus could modify the generation of specific
T cell clones in chimeric subjects and these mechanisms could be important in the induction of central tolerance against foreign
antigens important in allo-transplantation. In this review, we discuss the genetics of chimerism and tetragametism and its
potential role in thymic selection and the relevance in allotransplantation and autoimmune disorders.
This review is dedicated to the memory of Robert A. Good, MD, PhD, an outstanding physician and scientist, one discoverer
of the functions of the Thymus in immunobiology and the pioneer of human bone marrow allotransplantation.
Presented at the First Robert A Good Society Symposium, St. Petersburg, FL 2006. 相似文献