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The characterization of the T-cell receptor (TCR) repertoire of CD4+ regulatory T cells (T(R)) has been limited due to the RNA degradation that results following permeabilization and fixation as routinely used for intracellular staining of Foxp3. In the present study the clonal composition of human umbilical cord blood (UCB) and adult peripheral blood mononuclear cell (PBMC) CD4+ T(R) and non-T(R) was characterized by a DNA-based multiplex PCR which allowed for the consistent clonotypic characterization of cells that have undergone fixation and permeabilization. To validate this method, CD8+ T cells from two HLA A()0201 individuals were sorted and compared clonotypically based upon their ability either to secrete interferon-gamma in response to a CMV pp65 epitope or to bind to the corresponding pMHC I tetramer. Clonotypes shared between the CD4+CD25+Foxp3+ and CD4+CD25+Foxp3- subsets were observed in all 3 UCB and in one adult PBMCs, suggesting that na?ve and memory CD4+ T(R) can share the same clonotypes as CD4+ non-T(R) in humans.  相似文献   
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Background

Sepsis complication is a major cause of death in multiple trauma critically ill patients. Defensin (cysteine rich anti-microbial peptides), as an important component of immune system, might play an important role in this process. There is also rising data on immunological effects of N-acetyl-cysteine (NAC), a commonly used anti-oxidant in oxidative stress conditions and glutathione (GSH) deficiencies. The aim of the present study was to evaluate the potential beneficial effects of NAC administration on multiple trauma patients with sepsis.

Methods

In a prospective, randomized controlled study, 44 multiple trauma critically ill patients who were mechanically ventilated and met the criteria of sepsis and admitted to the intensive care unit (ICU) were randomized into two groups . Control group received all standard ICU therapies and NAC group received intravenous NAC 3 gr every 6 hours for 72 hours in addition to standard therapies. Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores, length of ICU stay, ICU mortality were recorded. Levels of serum Immunoglobulin M (IgM), Human β-Defensin 2 (HβD2) and GSH were assessed at baseline and 24, 72, 120 hours after intervention.

Results

During a period of 13-month screening, 44 patients underwent randomization but 5 patients had to be excluded. 21 patients in NAC group and 18 patients in control group completed the study. For both groups the length of ICU stay, SOFA score and systemic oxygenation were similar. Mortality rate (40% vs. 22% respectively, p = 0.209) and ventilator days (Mean ± SD 19.82 ± 19.55 days vs. 13.82 ± 11.89 days respectively, p = 0.266) were slightly higher for NAC group. IgM and GSH levels were similar between two groups (p = 0.325, 0.125 respectively), HβD2 levels were higher for NAC group (at day 3).

Conclusion

High dose of NAC administration not only did not improve patients’ outcome, but also raised the risk of inflammation and was associated with increased serum creatinine.  相似文献   
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IntroductionThe caudal extension graft is usually a cartilage graft that overlaps the caudal margin of the nasal septum. A combination of the caudal extension graft and the tongue-in-groove technique is used to stabilize the nasal base, set tip projection, and refine the alar-columellar relationship.ObjectivesIn this study we present some new modifications to the placement of caudal extension grafts in rhinoplasty.MethodsThis study is a retrospective review of a prospectively collected database of 965 patients who underwent septorhinoplasty from June 2011 to July 2015. Of these, 457 patients required a caudal extension graft and were included in the study. Minimum follow-up was 13.2 months with a mean follow-up time of 17.4 months.ResultsIn most cases, comparison of photographs before and after surgery were satisfactory and showed improved contour. Minor deformity was detected in 41 patients and 11 patients needed revision surgery.ConclusionWith these modifications the surgeon can employ the caudal extension graft even in angulated caudal septal deviations. A variety of methods have been proposed for correction of caudal nasal deviation.  相似文献   
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Purpose

This paper reports the authors’ 19 years experience with pediatric intrasacral rod fixation.

Methods

After insertion of two cannulated screws in S1 with and an original template guiding them into the anterior third of the endplate, two short fusion rods were inserted into the sacrum according to Jackson’s technique distally to S3. In neuromuscular scoliosis, pelvic obliquity was reduced by connecting the proximal and distal constructs, distraction or compression, and in situ rod bending. In children with high-grade spondylolisthesis, lumbosacral kyphosis was reduced by rotation of the sacrum and in situ bending.

Results

There were no direct neurological or vascular injuries. The main complication was infection (7 %). No pseudarthrosis or significant loss of correction at the lumbosacral junction was observed during follow-up.

Conclusions

Intrasacral rod fixation appears to be safe and reliable for lumbopelvic fusion in pediatric patients.

  相似文献   
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A 78-year-old white woman returned for a routine 6-month skin cancer examination. She had a history of actinic keratosis and multiple basal cell carcinomas. She had no personal or family history of dysplastic nevi or melanoma. The patient was asymptomatic and unaware of any new or changing skin lesions. The patient had multiple lentigines, hemangiomas, and actinic and seborrheic keratoses on all sun-exposed areas. There were no less than 10 seborrheic keratoses on the right mid-back, and one was found to have a 1-cm, reddish nodule asymmetrically located within it (Figs 1 and 2). A clear papule on the left preauricular area was found on biopsy to be a basal cell carcinoma. The nodule on the back was still present 1 month later and it was felt that further evaluation was indicated. As melanoma has been reported to develop in seborrheic keratoses, we decided to examine the lesion using digital dermoscopy. With digital dermoscopy, a well-demarcated reddish nodule was asymmetrically located within a brown lesion. It blanched significantly with pressure. Within the nodule, there were dotted and irregular linear vessels (atypical vascular pattern; also known as polymorphous vascular pattern) and regular-appearing brown dots. Surrounding the reddish nodule, there were pale and pigmented, comedo-like openings, fissures, and ridges (brain-like appearance). Some of the follicular openings appeared to be within the wall of the nodule (Figs 3 and 4). Comedo-like openings, fissures, and ridges are primary dermoscopic criteria for the diagnosis of a seborrheic keratosis; however, the vascular pattern seen has not been reported in seborrheic keratosis. Due to the patient's age and the rarity of significant pathology arising in a seborrheic keratosis, a shave biopsy was performed. To our surprise, the specimen was interpreted by an experienced dermatopathologist as a well-differentiated eccrine porocarcinoma. Due to the high local recurrence rate and metastatic potential of this carcinoma, the patient was referred for Mohs' surgery. Both the basal cell carcinoma and the eccrine porocarcinoma were excised in one stage. A metastatic work-up was negative and the patient appears to be doing well.  相似文献   
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