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111.
The autologous bone substitutes are the gold standard of orthopedic surgery for the treatment of severe losses of substance. Nevertheless there are different issues, from co-morbidity of the donor site, the limited quantity and poor osteogenic properties. To overcome these limits the bank of the skeletal muscle tissue of the Rizzoli Institutes in cooperation with FIN-ceramic Faenza SpA have developed DBSint: a new synthetic bone composite, equipped with biomimetic and osteoinductive properties, consisting of demineralized bone matrix conveyed by nanostructured hydroxyapatite enriched with magnesium. The DBSint has recently been evaluated with a clinical preliminary study with the purpose to analyze the ability to form new bone tissue and the time necessary to determine bone repair. We enrolled 36 patients with indication to perform a valgus osteotomy of the tibia, divided into 3 groups, respectively, treated with nano hydroxyapatite structured in the form of paste (SINTlife) currently on the market, the cortico-cancellous bone chips provided by the BTM-IOR, and finally DBSint. There were no adverse effects, we performed biopsies and histological exam, and radiographic assessment, respectively, at 40 days and 6 months after treatment, showing that the DBSint is able to promote a fast bone regeneration, higher than in the two groups treated with Sintlife and homologous bone.  相似文献   
112.

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.
  相似文献   
113.

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   
114.
115.
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   
116.
We carried out fluorescence in situ hybridization (FISH) studies on 18 Ph+ chronic myeloid leukemia (CML) cases with chromosome 22 genomic deletions with the Vysis BCR-ABL dual-color/dual-fusion probe (BCR-ABL DC/DF) to compare the hybridization patterns obtained with this approach to those obtained with the "home brew" BAC/PAC system. Our results are the following: chromosome 22 microdeletions less than 400 kilobases (Kb) were not detected by the BCR DC/DF probe; FISH analysis with the BCR DC/DF probe in cases bearing chromosome 22 microdeletions ranging from 400 to 700 Kb produced a faint signal on the der(9); and the BCR-ABL DC/DF FISH pattern was comparable to the one obtained by the home brew probe in the presence of a 900-Kb chromosome 22 microdeletion. Our home-brew FISH system represents an accurate method for revealing a subset of CML patients with der(9) microdeletions.  相似文献   
117.
Introduction: Effective resuscitation with human albumin solutions is achieved with less fluid than with crystalloid solutions. However, the role of albumin in today’s critical care unit is also linked to its multiple pharmacological effects.

Areas covered: The potential clinical benefits of albumin in select populations of critically ill patients like sepsis seem related to immunomodulatory and anti-inflammatory effects, antibiotic transportation and endothelial stabilization. Albumin transports many drugs used in critically ill patients. Such binding to albumin is frequently lessened in critically ill patients with hypoalbuminemia. These changes could result in sub-optimal treatment. Albumin has immunomodulatory capacity by binding several bacterial products. Albumin also influences vascular integrity, contributing to the maintenance of the normal capillary permeability. Moreover, the albumin molecule encompasses several antioxidant properties, thereby significantly reducing re-oxygenation injury, which is especially important in sepsis. In fact, most studies of albumin administration are a combination of a degree of resuscitation with a degree of maintenance or supplementation of albumin.

Expert commentary: The potential clinical benefits of the use of albumin in selected critically ill patients such as sepsis seem related to its immunomodulatory and anti-inflammatory effects, antioxidant properties, antibiotic transportation and endothelial stabilization. Additional studies are warranted to further elucidate the underlying physiologic and molecular rationale.  相似文献   

118.
Infliximab, a tumor necrosis factor-alpha inhibitor, is increasingly used for the therapy of different inflammatory conditions. We report the first case of cryptococcal meningitis in a patient treated with infliximab and other immunosuppressive agents, and review a further 5 reported cryptococcal infections. All of them involved fungal pneumonia. Outcome was favorable in all cases.  相似文献   
119.
120.
World Journal of Surgery - The outcomes of liver resection (LR) with a narrow margin in patients with transplantable hepatocellular carcinoma (HCC) have not been studied. The aim was to assess...  相似文献   
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