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1.
Mosaic ring 12p and total anomalous pulmonary venous return   总被引:1,自引:0,他引:1  
An infant born with total anomalous pulmonary venous return (TAPVR) was found to have an extra chromosome present as a small ring. Spectral karyotyping and FISH analysis identified the material as a duplication involving the short arm of chromosome 12. Previous cases describing a variety of cytogenetic abnormalities that have been associated with TAPVR are reviewed along with prior cases of duplication 12p with their associated findings. We believe ours is the first case to report the occurrence of mosaic ring 12p and its association with TAPVR.  相似文献   
2.
Expression of the intermediate filament protein vimentin, and loss of the cellular adhesion protein uvomorulin (E-cadherin) have been associated with increased invasiveness of established human breast cancer cell linesin vitro andin vivo. In the current study, we have further examined these relationships in oncogenically transformed human mammary epithelial cells. A normal human mammary epithelial strain, termed 184, was previously immortalized with benzo[a]pyrene, and two distinct sublines were derived (A1N4 and 184B5). These sublines were infected with retroviral vectors containing a single or two oncogenes of the nuclear, cytoplasmic, and plasma membrane-associated type (v-ras H, v-ras Ki, v -mos, SV40T and c -myc). All infectants have been previously shown to exhibit some aspects of phenotypic transformation. In the current study, cellular invasiveness was determinedin vitro using Matrigel, a reconstituted basement membrane extract. Lineage-specific differences were observed with respect to low constitutive invasiveness and invasive changes after infection withras, despite similarras-induced transformation of each line. Major effects on cellular invasiveness were observed after infection of the cells with two different oncogenes (v-ras H + SV40T and v -ras H + v -mos). In contrast, the effects of single oncogenes were only modest or negligible. All oncogenic infectants demonstrated increased attachment to laminin, but altered secretion of the 72 kDa and 92 kDa gelatinases was not associated with any aspect of malignant progression. Each of the two highly invasive double oncogene transformants were vimentinpositive and uvomorulin-negative, a phenotype indicative of the epithelial-mesenchymal transition (EMT) previously associated with invasiveness of established human breast cancer cell lines. Weakly invasive untransformed mammary epithelial cells in this study were positive for both vimentin and uvomorulin, suggesting that uvomorulin may over-ride the otherwise vimentin-associated invasiveness.  相似文献   
3.
Gemcitabine is a chemotherapy agent with efficacy in the treatment of lung, pancreas, bladder and breast cancer. It inhibits DNA synthesis by interfering with cytidine triphosphate production and also inhibits the activity of ribonucleotide reductase. Gemcitabine may potentiate fluorouracil's inhibition of thymidylate synthase. This inhibition would be expected to be sequence dependent, occurring only if gemcitabine were administered following fluorouracil (5FU).The combination of leucovorin, 5-FU, and gemcitabine was assessed in this phase I trial. Eligibility requirements included refractory solid tumor malignancy; adequate hematologic, renal and hepatic reserve; no prior therapy with the combination of leucovorin and 5FU, or with gemcitabine; ECOG performance status 0–2, and signed informed consent.Eleven men and nine women were eligible. The median age was 52.5 years and the median performance status was 1. All but three patients had prior chemotherapy. The starting doses were leucovorin 20 mg/m2, 5FU 255 mg/m2 and gemcitabine 600 mg/m2. 5FU and gemcitabine were escalated in tandem to 340 mg/m2 and 800 mg/m2 and thereafter to 425 mg/m2 and 1000 mg/m2, respectively. Gemcitabine administration always followed that of 5FU by 30 minutes. The median number of cycles was 2 (range 1–32). Two patients at the starting dose had disease progression within the first cycle with one death on day 28. One patient with cholangiocarcinoma had a partial response and remained on study for 40 months. There were no other responses.The maximum tolerated dose is leucovorin 20 mg/m2, 5FU 340 mg/m2, and gemcitabine 800 mg/m2. The impact of drug sequence remains undetermined.  相似文献   
4.
Sirenomelia, also known as the mermaid syndrome, is a rare congenital malformation of uncertain etiology. It is characterized by fusion of the lower limbs and commonly associated with severe urogenital and gastrointestinal malformations. In this report, we describe the first case of an infant with sirenomelia and a massive angiomatous lumbosacral myelocystocele.  相似文献   
5.
Introduction: Epigenetic mechanisms of gene regulatory control play fundamental roles in developmental morphogenesis, and, as more recently appreciated, are heavily implicated in the onset and progression of neoplastic disease, including cancer. Many epigenetic mechanisms are therapeutically targetable, providing additional incentive for understanding of their contribution to cancer and other types of neoplasia.

Areas covered: The Jumonji-domain histone demethylase (JHDM) family exemplifies many of the above traits. This review summarizes the current state of knowledge of the functions and pharmacologic targeting of JHDMs in cancer and other neoplastic processes, with an emphasis on diseases affecting the pediatric population.

Expert opinion: To date, the JHDM family has largely been studied in the context of normal development and adult cancers. In contrast, comparatively few studies have addressed JHDM biology in cancer and other neoplastic diseases of childhood, especially solid (non-hematopoietic) neoplasms. Encouragingly, the few available examples support important roles for JHDMs in pediatric neoplasia, as well as potential roles for JHDM pharmacologic inhibition in disease management. Further investigations of JHDMs in cancer and other types of neoplasia of childhood can be expected to both enlighten disease biology and inform new approaches to improve disease outcomes.  相似文献   

6.
BACKGROUND: We previously demonstrated that short-cycle structured intermittent therapy (SIT; 7 days without therapy followed by 7 days with antiretroviral therapy [ART]) with a ritonavir-boosted, indinavir-based, twice-daily regimen maintained suppression of plasma HIV viremia while reducing serum levels of lipids. Adherence to such a regimen may be problematic for certain patients. METHODS: Eight patients with a history of receiving combination ART that maintained suppression of plasma HIV RNA to <50 copies/mL received a once-daily SIT regimen of didanosine, lamivudine, and efavirenz. RESULTS: For 7 patients, suppression of plasma HIV RNA to <50 copies/mL was maintained for 60-84 weeks. Four patients with adequate samples had no evidence for an increase in plasma viremia for up to 72 weeks, by use of an assay with a limit of detection of <1 copy/mL. The lack of rebound viremia may be the result of the persistence of efavirenz in plasma on day 7 of the no-therapy period, as was detected in 7 of 7 patients. There was no significant change in CD4(+) T cell counts or serum hepatic transaminase or lipid levels. CONCLUSION: A once-daily short-cycle SIT regimen maintained suppression of plasma HIV RNA while preserving CD4(+) T cell counts. Such a regimen may have importance in resource-limited settings where the monetary cost of continuous ART is prohibitive.  相似文献   
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We analyzed preoperative patient characteristics and postoperative functional outcomes to identify the most predictive preoperative characteristics of postoperative functional outcome for Cruciate Retaining (CR) TKA. In a prospective, multicenter study, 307 knees with minimum 2-year follow-up were first divided into groups based on 2-year functional performance. Logistic regression then determined SF-36 General Health Score (GHS) to be the most predictive preoperative patient characteristic. Subsequently, a second analysis was performed using preoperative SF-36 GHS to stratify patients into groups. Statistical significance was achieved in both analyses by gender, BMI and hypertension. Statistical significance was achieved in a single analysis by age, preoperative narcotic use, preoperative metabolic medication usage, preoperative pulmonary disease and preoperative use of medication for anxiety or depression.  相似文献   
10.
Differences in drug metabolism associated with UGT1A1 polymorphism could result in individualized local response to hepatic chemoembolization with irinotecan-eluting beads (DEBIRI) or predictable toxicities. Five patients with inoperable hepatic metastases from colorectal or anal malignancies treated with DEBIRI were assessed for UGT1A1 mutations. No difference in area under the curve (AUC) for SN38 in normal liver and tumor tissue samples was noted with variant or wild-type UBT1A1 (P = .16 and P = .05, respectively). Plasma SN-38 AUC was significantly lower in wild-type compared to variant patients (P < .0001). UGT1A1 genotype may not be predictive of hematologic toxicity after DEBIRI.  相似文献   
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