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51.
52.
Background: Abdominal lipectomy is becoming an increasingly common surgical procedure in patients with esthetic deformities resulting from massive weight loss induced by bariatric surgery. Sometimes a midline incisional hernia coexists with the pendulus abdomen. Herein presented is a technique to perform a retromuscular mesh repair of the incisional hernia while sparing the umbilicus. Methods: The abdominal lipectomy with concomitant retro-muscular mesh repair of a midline incisional hernia is done sparing the vascular supply of the umbilicus on one side only. Results: 5 consecutive women with pendulus abdomen resulting from bariatric surgery-induced massive weight loss and concomitant midline incisional hernia underwent abdominal lipectomy and incisional hernia mesh repair. Mean BMI was 28.6 kg/m2 (range 26–35), one patient was a smoker, and another had type 2 diabetes requiring oral hypoglycemic agents. Two patients had had a previous incisional hernia repair with intraperitoneal mesh. One patient had partial necrosis of the umbilicus and another experienced necrosis of only the epidermis that recovered fully. Conclusions: The umbilicus can be safely spared during abdominal lipectomy with concomitant midline incisional hernia mesh repair. Recurrent incisional hernia and common risk factors for wound healing such as diabetes and obesity increase the risk of umbilical necrosis.  相似文献   
53.
Axon-derived neuregulins (NRGs) are a family of growth factors whose binding to ErbB tyrosine kinase receptors promotes the maturation, proliferation and survival of Schwann cells (SCs). Correct NRG/ErbB signaling is essential for the homeostasis of axonal-glial complexes and seems to play a role in peripheral nerve repair. The potential involvement of ErbB receptors in human peripheral neuropathies has not been clarified. Therefore, we assessed the immunoreactivity for EGFR (ErbB1), ErbB2, and ErbB3 in nerve biopsies from patients with different forms of Charcot-Marie-Tooth disease, type 1, (CMT1), as compared to others with inflammatory neuropathies and controls. The most notable changes consisted in the overexpression of ErbB2 and ErbB3 by SCs of nerves from CMT1A patients. These findings are consistent with an impairment of SC differentiation and expand the molecular phenotype of CMT1A. The upregulation of these receptors may play a role in the inhibition of myelination or in the promotion of recurrent demyelination and axonal damage.  相似文献   
54.
OBJECTIVE: The study aims to verify whether phonologic and rapid automatized naming (RAN) deficits are present and associated in Italian dyslexic children and whether they differentially affect dyslexics with and without a history of previous language delay (LD). BACKGROUND: According to the phonologic core deficit hypothesis, dyslexia may stem from impairment of the representation and manipulation of phonemes and may be closely associated with oral language deficits. However, deficits in tasks not requiring fine-grained phonologic representations, such as RAN, have also been described in dyslexic children. METHODS: Thirty-seven children were selected on the basis of a reading deficit and were assigned to 2 groups according to whether or not they had a history of early LD as determined retrospectively by parental report. A battery of reading and writing, verbal working memory, metaphonologic, RAN, and visual search tests were administered. RESULTS: RAN deficits were shared by most dyslexics (with and without a history of LD), whereas phonologic deficits were mainly associated with a previous LD. This last condition did not result in a more profound impairment of reading and writing decoding skills. CONCLUSION: In a shallow orthography such as Italian, RAN, not phonologic deficits, may represent the main cognitive marker of developmental dyslexia.  相似文献   
55.
OBJECTIVES: To investigate clinical and psychological features of patients with anorexia nervosa (AN) with a previous history of bulimia nervosa. METHOD: Three hundred thirty-three patients with a full diagnosis of AN were assessed by the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, the Eating Disorders Inventory, and the Hopkins Symptom Checklist. RESULTS: Twenty-four patients (7%) reported a previous diagnosis of bulimia nervosa and were compared with a control group of 48 patients without a history of bulimia, matched for diagnostic subtype. Among the patients with a history of bulimia nervosa, 11 were of the restricting type and 13 of the binge eating/purging type. Among restricting anorexic patients, those with a history of bulimia reported greater age of onset, more psychiatric symptoms, more family psychiatric morbidity, and a higher rate of sexual abuse. On the contrary, among patients with the AN bingeing-purging subtype, the presence of a previous bulimia nervosa was not associated with any of the investigated variables. CONCLUSIONS: Patients with restricting AN who report a history of previous bulimia nervosa are not frequent among those referring to an outpatient eating disorders unit. However, our findings in this small group of subjects confirm that a lifetime history of bingeing and purging in patients with eating disorder, irrespective of when it occurs, is always associated with more psychopathology compared with those restricting patients with AN who have never had a period of bingeing and purging.  相似文献   
56.

OBJECTIVE

The gut environment modulates the pathogenesis of type 1 diabetes (T1D), but how it affects autoimmunity toward pancreatic β-cells, a self-tissue located outside the intestine, is still unclear. In the small intestine, lamina propria dendritic cells (LPDCs) induce peripheral differentiation of FoxP3+ regulatory T (Treg) cells. We tested the hypothesis that the intestinal milieu impinges on human T1D by affecting differentiation of FoxP3+ Treg cells.

RESEARCH DESIGN AND METHODS

We collected duodenal biopsies of 10 T1D patients, 16 healthy subjects, and 20 celiac individuals and performed a fluorescent-activated cell sorter analysis to measure percentages of various immune cell subsets, including CD4+ and CD8+ T cells, NK cells, γδ T cells, CD103+CD11c+ LPDCs, and CD4+CD25+FoxP3+CD127 Treg cells. In parallel, we assessed the tolerogenic function (i.e., capacity to induce differentiation of FoxP3+ Treg cells) by LPDCs of T1D patients and control subjects.

RESULTS

Our analysis revealed a significant reduction in the percentage of intestinal CD4+CD25+FoxP3+CD127 Treg cells in T1D patients compared with healthy subjects (P = 0.03) and celiac individuals (P = 0.003). In addition, we found that LPDCs from T1D patients completely lacked their tolerogenic function; they were unable to convert CD4+CD25 T cells into CD4+CD25+FoxP3+CD127 Treg cells.

CONCLUSIONS

Our data indicate that T1D patients have a reduced number of intestinal FoxP3+ Treg cells as a result of their defective differentiation in the gut. These findings suggest that intestinal immune regulation is not only calibrated to tolerate commensal bacteria and food components but also is instrumental in maintaining immune tolerance toward pancreatic β-cells and preventing T1D.Type 1 diabetes (T1D) is a destructive islet β-cell specific autoimmune disease resulting from a yet undefined interaction between genetic and environmental factors (1). A dramatic increase in T1D incidence was recorded in most developed countries in the past 40 years (e.g., a threefold increase in Western countries) (2,3). The steady and rapid increase in T1D incidence cannot be ascribed to genetic variations and, thus, it must be related to environmental changes. Environmental agents such as viral infections (i.e., enteroviruses and rotaviruses) (4,5), reactions to dietary antigens (i.e., cow’s milk and gluten) (68), and microbiota alterations (9) that act at the intestinal level have been observed in association with, or as risk factors for, the development of T1D. The observation that development of clinical diabetes in patients is preceded by intestinal alterations such as increased permeability, immune activation, and ultrastructural abnormalities of the epithelium (1016) provides additional evidence on the crucial role of the gut environment in human T1D. Although existing evidence is suggestive of a causative link between the gut milieu and the pathogenesis of T1D, it is still unclear whether and by which mechanism(s) a dysfunction in the intestine promotes autoimmunity elsewhere (i.e., in the pancreatic β-cells) and if it does, how this process occurs.Important immune regulatory mechanisms reside in the intestinal mucosa. FoxP3+ regulatory T (Treg) cells, a Treg cell subset that is instrumental to controlling T1D (17), arise centrally in the thymus and peripherally in the gut (18). Specifically, lamina propria CD103+CD11c+ dendritic cells (LPDCs) are responsible for extrathymic FoxP3+ Treg cell development and expansion (18,19). Considering the key immune regulatory role of FoxP3+ Treg cells, it is clear that their defective peripheral differentiation in the gut could lead to failure of self-tolerance and autoimmune disease, particularly in tissues such as pancreatic islets and lymph nodes that are directly connected to the intestinal mucosa and gut-associated lymphoid tissue (20).Here we demonstrate that the extrathymic differentiation of FoxP3+ Treg cells by gut-resident CD103+CD11c+ dendritic cells (DCs) is selectively impaired in humans affected by T1D. Our findings indicate that organ-specific autoimmune diseases such as T1D could be initiated and possibly maintained by virtue of changes in peripheral FoxP3+ Treg cell differentiation and/or expansion in the gut.  相似文献   
57.
BACKGROUND: There is a major clinical need for strategies for adequately reconstructing the soft tissue defects found after deep burns, tumor resection, or trauma. A promising solution is adipose tissue engineering with preadipocytes, stem-cell derived precursors of the adipose tissue, implanted within biomaterials. This pilot study evaluated hyaluronan gels mixed with autologous undifferentiated preadipocytes in a pig model for their potency to generate new fat. MATERIALS AND METHODS: Preadipocytes were isolated from intra-abdominal pig fat by collagenase digestion, plated on fibronectin-coated culture dishes in Dulbecco's modified Eagle medium/Ham's F12 (Biochrom, Berlin, Germany) combined with 10% pig serum, expanded, and mixed with hyaluronan gel. Two types of gels with varying degrees of amidation of the carboxyl groups were tested (HYADD3, HYADD4). Cell-loaded gels and unseeded controls were injected subcutaneously into the ears of three pigs, explanted at 6 wk, and analyzed histologically. RESULTS: Both cell-loaded specimens were detected macroscopically. They demonstrated a slight volume effect with limited stability after 6 wk. Unloaded HYADD3 and HYADD4 controls could not be identified at the time of explantation. Histology of HYADD3 revealed islets of mature adipocytes and vessels embedded in fat tissue surrounded by gel. In contrast, no fat formation was found in HYADD4 gels when implanted in the ear. CONCLUSIONS: Histological findings demonstrate that HYADD3 is a promising gel for generating adipose tissue. Even though HYADD3 might be a potential material for the reconstruction of small tissue defects, the question remains as to whether the adipose tissue within the gel is attributable to preadipocyte maturation or ingrowth from neighboring tissue.  相似文献   
58.
Background Recently, it has been demonstrated that surgical treatment of hemorrhoids in a day-care basis is possible and safe. The aim of this study was to compare the Longo stapled hemorrhoidopexy (SH) and the Milligan–Morgan hemorrhoidectomy (MMH). Methods One hundred seventy one patients (95 cases in SH group and 76 cases in MMH group) entered the study: 83 cases were III degree hemorrhoids, 88 IV degree. A priori and a post hoc power analysis were performed. Results, prospectively collected, were compared using chi squared test and student t test. Visual analog scale was used for pain evaluation. Postoperative pain, duration of pain, wound secretion, bleeding, resumption of a normal lifestyle, and postoperative complication were evaluated. Results Surgical time was 28.41 ± 10.78 for MMH and 28.30 ± 13.28 min in SH (P = 0.94). Postoperative pain was not different between MMH and SH during the first two postoperative days (4.73 ± 2.91 vs 5.1 ± 3.048; P = 0.4), during the following 6 days, patients treated with SH had less pain (4.63 ± 2.04 in MMH vs 3.60 ± 2.35 in SH; P = 0.006). In the SH group, seven patients needed further hospital stay for complicated course. SH showed higher incidence of anal fissure compared with MMH (6.3% vs 0%; P = 0.025) but no differences in urinary retention, anal stricture, urgency, or anal hemorrhage. Conclusions This study confirms that SH is associated with less postoperative pain and shorter postoperative symptoms, compared with MMH. SH may be a viable addition to the therapy for hemorrhoids with some advantages in early postoperative pain and some disadvantages in postoperative complications and costs.  相似文献   
59.
The wide diffusion of laparoscopic adjustable gastric banding as a common surgical procedure for the treatment of morbidly obese patients can be attributed not only to the easy surgical technique, the ability to caliber the stoma, and the potential for reversibility, but also to the fact that this procedure is associated with a low rate of immediate postoperative complications compared to other more complex bariatric procedures. Herein reported is the case of a 63-year-old morbidly obese woman who sustained an iatrogenic injury of the intrathoracic esophagus during a laparoscopic adjustable gastric banding procedure. The putative mechanism of this previously unreported complication of laparoscopic adjustable gastric banding and the therapeutic options are discussed. The patient was initially treated with left pleural cavity drainage, antibiotics and the placement of an endoscopic silicone covered stent to cover the esophageal tear. Nine days later she underwent surgery through left thoracotomy due to the persistence of the esophageal leak. Esophageal perforation is a potentially life- threatening complication that may occur during a laparoscopic gastric banding procedure. The conservative treatment with an endoscopic stent should be reserved to patients with no signs of progressive systemic inflammation and include the drainage of the pleural cavity and the mediastinum, the endoscopic lavage and debridement. Standard surgical treatment with direct repair should not be retarded in case of persistence of the leak.  相似文献   
60.
Mutations in the X-linked androgen receptor (AR) gene cause androgen insensitivity syndrome (AIS), resulting in an impaired embryonic sex differentiation in 46,XY genetic men. Complete androgen insensitivity (CAIS) produces a female external phenotype, whereas cases with partial androgen insensitivity (PAIS) have various ambiguities of the genitalia. Mild androgen insensitivity (MAIS) is characterized by undermasculinization and gynecomastia. Here we describe a 2-month-old 46,XY female patient, with all of the characteristics of CAIS. Defects in testosterone (T) and dihydrotestosterone (DHT) synthesis were excluded. Sequencing of the AR gene showed the presence in exon 6 of a T to C transition in the second base of codon 790, nucleotide position 2369, causing a novel missense Leu790Pro mutation in the ligand-binding domain of the AR protein. The identification of a novel AR mutation in a girl with CAIS provides significant information due to the importance of missense mutations in the ligand-binding domain of the AR, which are able to induce functional abnormalities in the androgen binding capability, stabilization of active conformation, or interaction with coactivators.  相似文献   
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