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41.
OBJECTIVE: To determine incidence trends and outcomes for pediatric patients with malignant breast disease. METHODS: The Surveillance, Epidemiology, and End Results registry was examined for all females 19 years of age and younger diagnosed with a malignant breast tumor between 1973 and 2004. RESULTS: A total of 75 patients with malignant breast tumors were identified. Overall, 14.5% of patients had in situ tumors, and 85.5% had invasive disease. Tumors were classified as being either carcinomas (n = 41, 54.7%) or sarcomas (n = 34, 45.3%). The majority of sarcomatous lesions were phyllodes tumors (n = 29, 85.5%), whereas most carcinomas were of a ductal etiology (n = 19, 46.3%). The age-adjusted incidence of all malignant pediatric breast tumors in 2003 was 0.08 cases per 100,000 people (0.03 carcinoma and 0.06 sarcoma cases per 100,000 people). In the carcinoma group, regionally advanced disease was present in 11 patients (26.8%), whereas only 3 patients (7.3%) presented with metastatic disease. All patients with sarcomatous tumors presented with localized disease. Adjuvant radiation therapy was administered in only 9.8% of carcinomas and 8.8% of sarcomas, and 85.4% of carcinoma patients and 97.1% of sarcoma patients underwent surgical resection for their primary disease. Subgroup analysis revealed 5- and 10-year survival rates of 89.6% for patients with sarcomatous tumors and 63.1% and 54.3% for carcinomas. CONCLUSIONS: Malignant pediatric breast malignancies remain relatively rare. The two most common histologies of breast neoplasms in children are malignant carcinomas followed by sarcomas. Although uncommon, malignant disease must be considered in the differential diagnosis of the pediatric patient with a breast mass.  相似文献   
42.
The frequency of prospective memory failure in individuals with severe traumatic brain injury (TBI) was investigated by comparison with a non-brain-injured control group. Self-awareness of prospective memory function was also assessed by comparing self-ratings with ratings by significant others. Study participants included 33 individuals with severe TBI and 29 non-brain-injured persons. Each participant nominated a close friend or relative who completed the informant's version of the questionnaire. Participants and their significant others both rated the participants' frequency of prospective memory lapses using the Comprehensive Assessment of Prospective Memory (CAPM). An independent groups design was adopted to compare the TBI and control groups. No significant difference was found between the TBI and control participants' self-ratings of frequency of prospective memory failure, but ratings by significant others were significantly different. The TBI group demonstrated less self-awareness (i.e. underestimated the frequency of prospective memory failure compared to significant others) than the control group.  相似文献   
43.
Background Osteosynthesis of clavicular fractures is sometimes indicated. Since plate fixation may lead to complications, we have used elastic stable intramedullary nailing and report our experience of midclavicular fractures in 32 adults.

Patients and methods From 2000 to 2005, we treated 32 adults (26 men), median age 40 (19-66) years, by intramedullary nailing with a titanium elastic nail (TEN). All patients were re-examined after median 27 (12-59) months.

Results Nonunion was not observed. 20 clavicles healed without shortening. 12 clavicles healed with shortening of more than 5 mm. Migration of the TEN in 8 patients required secondary shortening of the nail in 5 of them. Nail breakage after fracture healing was observed twice. The nails were removed in 29 patients after a median of 6 (1.3-15) months postoperatively. No patient sustained a re-fracture after TEN removal. The mean Constant score was 95 (SD 1.9) points and the mean DASH score was 5 (SD 2.3) points.

Interpretation Intramedullary stabilization of midclavicular fractures with a titanium elastic nail is a minimally invasive technique with good cosmetic and functional results. Intramedullary fixation can be seen as an alternative to plate fixation and nonoperative treatment.  相似文献   
44.
The myeloid differentiation protein 88 (MyD88) adapter protein is an important mediator of kidney allograft rejection, yet the precise role of MyD88 signaling in directing the host immune response toward the development of kidney allograft rejection remains unclear. Using a stringent mouse model of allogeneic kidney transplantation, we demonstrated that acute allograft rejection occurred equally in MyD88-sufficient (wild-type [WT]) and MyD88−/− recipients. However, MyD88 deficiency resulted in spontaneous diminution of graft infiltrating effector cells, including CD11bGr-1+ cells and activated CD8 T cells, as well as subsequent restoration of near-normal renal graft function, leading to long-term kidney allograft acceptance. Compared with T cells from WT recipients, T cells from MyD88−/− recipients failed to mount a robust recall response upon donor antigen restimulation in mixed lymphocyte cultures ex vivo. Notably, exogenous IL-6 restored the proliferation rate of T cells, particularly CD8 T cells, from MyD88−/− recipients to the proliferation rate of cells from WT recipients. Furthermore, MyD88−/− T cells exhibited diminished expression of chemokine receptors, specifically CCR4 and CXCR3, and the impaired ability to accumulate in the kidney allografts despite an otherwise MyD88-sufficient environment. These results provide a mechanism linking the lack of intrinsic MyD88 signaling in T cells to the effective control of the rejection response that results in spontaneous resolution of acute rejection and long-term graft protection.  相似文献   
45.
BACKGROUND: Primary congenital glaucoma generally presents with a classic clinical triad of photophobia, blepharospasm, and epiphora caused by the corneal changes that occur secondary to increased intraocular pressure (IOP). The condition typically presents bilaterally and is rarely hereditary. Onset is from age 2 months to 2 to 3 years. CASE REPORT: A 2-year, 5-month-old Hispanic boy presented with an enlarged right eye and an intermittent right exotropia, without tearing or photophobia. Examination also found high myopia and an optic nerve cup-to-disc ratio larger in the right than the left eye. Referral to a pediatric ophthalmologist was initiated. On the first examination under anesthesia (EUA), the child was diagnosed with unilateral megalocornea with a normal IOP. He did not have any other typical signs and symptoms of primary congenital glaucoma. An EUA 8 months later led to a diagnosis of primary congenital glaucoma based on the new appearance of Haab's striae, further enlargement of the cornea, and an elevated IOP. At this point, medical management was instituted. CONCLUSION: This case shows the importance of recognizing signs of primary congenital glaucoma so that appropriate management can begin as soon as possible to provide the best visual outcome for a child.  相似文献   
46.
The phenotype and function of murine dendritic cells (DCs) are primarily studied using bone-marrow-derived DCs (BM-DCs), but may be hampered by the heterogeneous phenotype of BM-DCs due to their differential state of maturation. Here we characterize a newly established murine DC line (SP37A3) of myeloid origin. During maintainance in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and M-CSF, SP37A3 cells resemble immature DCs characterized by low expression of major histocompatibility complex (MHC) II and costimulatory molecules and low T-cell stimulatory capacity. Upon stimulation, SP37A3 cells acquire a mature phenotype and activate naive T cells as potently as BM-DCs. Similar to BM-DCs, SP37A3 cells activated in the presence of dexamethasone-induced regulatory T cells, which were anergic upon restimulation and suppressed proliferation of naive T cells. This tolerogenic state was reflected by lower expression levels of costimulatory molecules and proinflammatory cytokines compared with mature cells, as well as up-regulated expression of FcgammaRIIB and interleukin-1RA (IL-1RA). SP37A3 cells were responsive to dexamethasone even when applied at later time points during activation, suggesting functional plasticity. Thus, DC line SP37A3 represents a suitable model to study functions of immature and mature as well as tolerogenic myeloid DCs, circumventing restrictions associated with the use of primary DCs and BM-DCs.  相似文献   
47.
The Hoxa9 and Meis1 genes represent important oncogenic collaborators activated in a significant proportion of human leukemias with genetic alterations in the MLL gene. In this study, we show that the transforming property of Meis1 is modulated by 3 conserved domains, namely the Pbx interaction motif (PIM), the homeodomain, and the C-terminal region recently described to possess transactivating properties. Meis1 and Pbx1 interaction domain-swapping mutants are dysfunctional separately, but restore the full oncogenic activity of Meis1 when cotransduced in primary cells engineered to overexpress Hoxa9, thus implying a modular nature for PIM in Meis1-accelerated transformation. Moreover, we show that the transactivating domain of VP16 can restore, and even enhance, the oncogenic potential of the Meis1 mutant lacking the C-terminal 49 amino acids. In contrast to Meis1, the fusion VP16-Meis1 is spontaneously oncogenic, and all leukemias harbor genetic activation of endogenous Hoxa9 and/or Hoxa7, suggesting that Hoxa gene activation represents a key event required for the oncogenic activity of VP16-Meis1.  相似文献   
48.
Purpose We investigated the impact of promoter methylation on APC protein expression in patients with hepatocellular carcinoma (HCC). Materials and methods 50 patients [HCC (n=19), liver metastasis (n=19), cholangiocellular cancer (n=7), and benign liver tumors (n=5)] were studied for methylation using Methylight analysis. APC mutation was investigated by protein truncation test and direct sequencing of genomic DNA. The protein expression was evaluated by immunohistochemistry and Western blot analysis. Results The APC promoter was hypermethylated in 81.8% of non-cancerous liver tissue samples. All HCC samples and ten patients with liver metastasis (52.6%) exhibited APC promoter methylation. The degree of methylation was significantly higher in samples from HCC compared to the non-cancerous liver tissue samples (63.1% vs. 24.98%; p=0.001). The level of APC protein expression was significantly reduced in HCC samples compared to that of the corresponding non-tumor liver tissue (p<0.05). Conclusions Promoter methylation of the APC gene seems to be of significance in hepatocarcinogenesis and results in reduced protein expression in HCC. Interestingly, APC promoter methylation is also present in the vast majority of non-cancerous liver tissue whose (patho)physiological function remains unresolved.  相似文献   
49.
Powdered infant formula is not sterile and may be intrinsically contaminated with pathogens, such as Salmonella enterica, that can cause serious illness in infants. In recent years, at least 6 outbreaks of Salmonella infection in infants that have been linked to the consumption of powdered infant formula have been reported. Many of these outbreaks were identified because the Salmonella strains were unique in some way (e.g., a rare serotype) and a well-established Salmonella surveillance network, supported by laboratories capable of serotyping isolates, was in place. Another common feature of the outbreaks was the low level of salmonellae detected in the implicated formula (salmonellae may be missed in routine testing). These outbreaks likely represent only a small proportion of the actual number of Salmonella infections in infants that have been linked to powdered infant formula. Managing this problem requires a multidimensional approach in which manufacturers, regulators, and caregivers to infants can all play a role.  相似文献   
50.
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