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1.
PurposeTo analyze the electroclinical features, aetiology and outcome in patients with normal neurological examination and psychomotor development who presented seizures during a mild gastroenteritis (MG).Patients and methodsEvaluation of the clinical charts of 22 patients who were assessed in the Neurology Department, Hospital Nacional de Pediatría Prof. Dr. JP Garrahan between 1999 and 2007.ResultsTwelve patients were boys and 10 were girls, the age of onset ranged from 5 to 26 months, and the median age was 10 months. Rotavirus antigen test in stool was positive in 9 of 18 studied patients. The seizures were brief, focal with secondary generalization in 15 patients (68.5%), apparently generalized in 5 (22.5%) and focal in two (9%). Seven of the patients (35%) had more than one seizure in 24 h. The interictal EEG was normal in all patients. Neuroradiological studies were performed in 19 patients with a normal result. No patient was put on long-term treatment with antiepileptic drugs. Four patients had subsequent mild gastroenteritis and two of them presented convulsions during the disease. After between 12 and 67 months of follow-up, all patients had normal psychomotor development and neurological examination.ConclusionsIn this study we confirmed the association of benign infantile seizures (BIS) and MG with or without rotavirus. The identification of this entity allows avoiding unnecessary complementary studies and treatment with antiepileptic drugs.  相似文献   
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Various methods of cryopreservation of human endothelial cells (EC) were studied to determine their viability and behavior when seeded onto vascular prostheses made of polytetrafluoroethylene (PTFE). Three different protocols were used: (1) cyropreservation of whole umbilical vein, (2) cyropreservation of freshly extracted umbilical EC in suspension, and (3) cryopreservation of EC derived from a first subculture. Fresh EC and EC from a first subculture were used as controls. The viability and growth of these cells in culture media were studied, and basal prostacyclin levels were determined. The cells were assessed morphologically after they were seeded onto PTFE discs. Our results showed that the cryopreservation method that maintained the greatest viability was that in which previously cultured EC were used. Basal prostacyclin levels were significantly different following cyropreservation. However, when these cells were seeded onto PTFE discs their behavior was similar to that of fresh EC.We thank W. L. Gore & Associates for supplying the prostheses used in this study.Supported by a grant from the Comision Interministerial de Cieucia y Tecnologia SAF 92/0875.  相似文献   
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Summary: Assembly of major histocompatibility complex (MHC) class I molecules in the endoplasmic reticulum is a highly coordinated process that results in abundant class I/peptide complexes at the cell surface for recognition by CD8+ T cells and natural killer cells. During the assembly process, a number of chaperones and accessory molecules, such as transporter associated with antigen processing, tapasin, ER60, and calreticulin, assist newly synthesized class I molecules to facilitate loading of antigenic peptides and to optimize the repertoire of surface class I/peptide complexes. This review focuses on the relative importance of these accessory molecules for CD8+ T‐cell responses in vivo and discusses reasons that may help explain why some CD8+ T‐cell responses develop normally in mice deficient in components of class I assembly, despite impaired antigen presentation.  相似文献   
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Long‐bone growth by endochondral ossification is cooperatively accomplished by chondrocyte proliferation, hypertrophic differentiation, and appropriate secretion of collagens, glycoproteins, and proteoglycans into the extracellular matrix (ECM). Before folding and entering the secretory pathway, ECM macromolecules in general are subject to extensive posttranslational modification, orchestrated by chaperone complexes in the endoplasmic reticulum (ER). ERp57 is a member of the protein disulfide isomerase (PDI) family and facilitates correct folding of newly synthesized glycoproteins by rearrangement of native disulfide bonds. Here, we show that ERp57‐dependent PDI activity is essential for postnatal skeletal growth, especially during the pubertal growth spurt characterized by intensive matrix deposition. Loss of ERp57 in growth plates of cartilage‐specific ERp57 knockout mice (ERp57 KO) results in ER stress, unfolded protein response (UPR), reduced proliferation, and accelerated apoptotic cell death of chondrocytes. Together this results in a delay of long‐bone growth with the following characteristics: (1) enlarged growth plates; (2) expanded hypertrophic zones; (3) retarded osteoclast recruitment; (4) delayed remodeling of the proteoglycan‐rich matrix; and (5) reduced numbers of bone trabeculae. All the growth plate and bone abnormalities, however, become attenuated after the pubertal growth spurt, when protein synthesis is decelerated and, hence, ERp57 function is less essential. © 2015 American Society for Bone and Mineral Research.  相似文献   
6.
Background. Over the years, reticular prostheses have undergone changes in their structure and composition to give rise to today's partially absorbable lightweight meshes. This study was designed to assess the biological and biomechanical behavior of these prostheses to establish whether they offer any advantages over nonabsorbable lightweight polypropylene prostheses. Materials and Methods. 7 × 5 cm defects were created in the anterior abdominal wall of New Zealand White rabbits and repaired by securing different prostheses to the edges of the defect with a running 4/0 polypropylene suture. The lightweight biomaterials compared were two nonabsorbable meshes: Parietene® and Optilene elastic®, and two partially absorbable prostheses: Vypro II® and Ultrapro®. At 14 and 90 days postimplant, tissue/prosthesis specimens were subjected to histological, immunohistochemical, shrinkage, and biomechanical analyses. Results. Adhesion formation on the peritoneum-facing surface of the meshes was significantly less extensive in the meshes with absorbable components at 90 days postimplant. The newly formed tissue around the prosthetic filaments was comprised of collagen fibers, fibroblasts, blood vessels, and macrophages. The partially absorbable meshes showed higher macrophage proportions (due to remnants of absorbable material and their structure) than the nonabsorbable meshes at 90 days, although differences were not significant. At 90 days postimplant, similar tensile strengths were recorded for all the implants. Conclusions. All the prosthetic materials induced good host tissue ingrowth, with no significant differences in tensile strength observed. Our findings suggest that partially absorbable lightweight prostheses could offer advantages over nonabsorbable lightweight meshes since less foreign material persists in the recipient, improving abdominal wall compliance.  相似文献   
7.

Introduction  

Resuscitation goals for septic shock remain controversial. Despite the normalization of systemic hemodynamic variables, tissue hypoperfusion can still persist. Indeed, lactate or oxygen venous saturation may be difficult to interpret. Our hypothesis was that a gastric intramucosal pH-guided resuscitation protocol might improve the outcome of septic shock compared with a standard approach aimed at normalizing systemic parameters such as cardiac index (CI).  相似文献   
8.
This study was designed to evaluate the behavior of a new composite polypropylene-polyurethane (PL-PU99) when placed in direct contact with the visceral peritoneum during the repair of an abdominal wall defect. Full-thickness abdominal wall defects (7 x 5 cm) were created in 36 anaesthetized white New Zealand rabbits. The defects were repaired with polypropylene prostheses or PL-PU99 prostheses (comprised of PL and a polyurethane sheet glued to the PL with acrylic adhesive) to establish two study groups (n = 18 each). Animals were sacrified 14, 30, or 90 days after implantation and prosthesis/surrounding tissue specimens were subjected to light and electron microscopy and morphometric analysis of the newly formed peritoneum. Immunohistochemical analysis was performed using the rabbit specific monoclonal antibody RAM-11. The biomechanical strength of the implants was also assessed. Firm adhesions were detected in the PL implants, whereas adhesions were practically non-existent in the PL-PU99 implants. The surface area covered by adhesions was greater (p < 0.01) in the PL group (7.36 vs. 0.11 cm2). The neoperitoneum formed after the implantation of a PL prosthesis was disorganized in structure, whereas that formed at the interface with the PL-PU99 prosthesis was structurally similar to the host peritoneum. The excellent performance of the PL-PU99 prosthesis shown in this study warrants further investigation into its use for the repair of abdominal wall defects when the prosthetic patch needs to be placed in contact with the intestinal loops.  相似文献   
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The association of epilepsy, occipital calcifications, and celiac disease has been recognized as a distinct syndrome. The objective of this study was to present the clinical, electrophysiologic, and neuroradiologic features in a series of patients with this syndrome. Thirty-two patients with the constellation of epilepsy, occipital calcifications, and celiac disease were identified in our epilepsy clinic. The mean age was 11 years and the mean length of follow-up was 7.4 years. The 1990 criteria of the European Society of Pediatric Gastroenterology and Nutrition were used to diagnose celiac disease. The Kruskal-Wallis statistics test was employed with a signficance of P < .05. Thirty-one patients had partial seizures, 21 of them with symptoms related to the occipital lobe. In most patients, the epilepsy was controlled or the seizures were sporadic. Three developed severe epilepsy. Occipital calcifications were present in all cases. Computed tomography in 7 patients showed hypodense areas in the white matter around calcifications, which decreased or disappeared after a period of gluten-free diet in 3 patients. A favorable outcome of epilepsy was detected in patients with the earliest dietary therapy. This study presents the largest series of children with this syndrome outside Italy. White-matter hypodensities surrounding calcifications are rarely reported. A prompt diagnosis of celiac disease might improve the evolution of the epilepsy and may improve cognitive status.  相似文献   
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