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21.

Background

Complete encasement of the inferior vena cava by retroperitoneal tumors is rare. Although replacement of the vena cava has been considered for various conditions in adults, it is rarely used in children except for challenging resections and as a last chance approach – often aiming more at debulking than cure.

Materials and methods

From January 2009 to February 2017, 4 patients (2 adrenal neuroblastomas, 1 renal cell carcinoma, 1 infantile fibrosarcoma) underwent elective en-bloc resection of tumor and of the infrahepatic portion of the inferior vena cava (IVC), with planned IVC prosthetic replacement. In three cases a portion of the left renal vein had to be resected as well, with the vein reanastomosed onto the prosthesis, and a concomitant auto-transplantation of the right kidney was associated in one neuroblastoma patient.

Results

All patients had an uncomplicated postoperative course. In one patient, the prosthetic conduit is patent at long-term (43?months), while the middle portion of the prosthesis did eventually thrombose at mid-term after surgery in the three others – with no related symptoms. Interestingly, all renal venous reconstructions remain patent. Three patients (2 neuroblastomas and 1 infantile fibrosarcoma) are alive and disease-free at 43, 74 and 108?months after surgery, respectively. One patient with renal cell carcinoma died of recurrence of the disease 21?months after surgery.

Conclusion

Resection and reconstruction of the vena cava, including the renal vein portion, can be considered and planned electively in case of tumoral encasement. This strategy is associated with good tolerance of the operation, low morbidity and satisfactory long-term function, even in cases with progressive and/or secondary partial thrombosis.

Level of Evidence

IV  相似文献   
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In Chile, sex work takes place covertly in a variety of venues and locations. Formative research using time-location sampling methods is important in order to understand the nature of this diversity. This study used qualitative methods to develop a typology of female sex work in the Metropolitan Region of Santiago, Chile, using semi-structured interviews, focus groups and ethnographic fieldwork during visits to sex work venues. The study identified seven types of venue, which reflect the context and regulatory framework of the country and the structural vulnerabilities that affect female sex workers in Chile. These venues and locations include: cafés con piernas (coffee with legs); nightclubs, topless bars and cabarets; brothels; hotels; street and highway soliciting; massage parlours; and private residences. Formative research methods were helpful in identifying and characterising the venues and locations in which sex work occurred. Barriers to accessing and mapping specific locations were also identified. Recommendations for addressing these barriers include working with non-governmental organisations to map venues and initiate contact with the populations of interest. A comprehensive typology of sex work in the Metropolitan Region of Santiago, Chile, is an essential element for future time-location sampling and bio-behavioural research in the context of second-generation surveillance for HIV and sexually transmitted infections in Chile.  相似文献   
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Problematic Internet use (PIU), which has become a global social issue, can be broadly conceptualized as an inability to control one's use of the Internet which leads to negative consequences in daily life. The aim of this paper is to give a brief overview of the gradually evolving body of literature on PIU. This shows that the definitions and diagnostic criteria that have been proposed, and the assessment tools that have been developed, stress similarities between PIU, addictive behaviours and impulse-control disorders. Disagreements regarding diagnostic criteria and the lack of large epidemiological studies have resulted in difficulties in establishing the prevalence of PIU in the general population. Studies suggest high comorbidity rates between PIU and numerous psychiatric disorders highlighting the importance of focusing on comorbidity in treatment. There is growing evidence that genetic, personality and individual differences in automatic and controlled aspects of self-regulation may promote the development of PIU. Pharmacological and psychotherapeutic treatments specific to PIU have received limited testing in large, rigorous studies however preliminary evidence suggests that both psychotropic medications (Escitalopram, Naltrexone and Methylphenidate) and cognitive behaviour therapy may have some utility in the treatment of PIU. More research is needed on areas which remain unclear and contribute to the prognosis of PIU, in particular the temporal relationships between psychiatric disorder and PIU, mechanisms of comorbidity and the more subtle psychological changes that occur through Internet use.  相似文献   
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Numerous intrinsic and extrinsic factors influence bone remodelling rates and have shown to affect the accuracy of histological aging methods. The present study investigates the rib cortex from two Mediterranean skeletal collections exploring the development of population-specific standards for histomorphometric age-at-death estimation. Eighty-eight standard ribs from two samples, Cretans and Greek-Cypriots, were processed histologically. Thirteen raw and composite histomorphometric parameters were assessed and observer error tested. The correlation between age and the parameters and the differences between sex and population subsamples were explored through group comparisons and analysis of covariance. General linear models assessed through data fit indicators and cross-validation were generated from the total dataset, and by sex and population subsamples. Most of the histological variables showed a statistically significant correlation with age with some differences observed by sex and by sample. From the twelve models generated, the optimal model for the whole sample included osteon population density (OPD), osteon perimeter, and osteon circularity producing an error of 10.71 years. When sex and samples were separated, the best model selected included OPD and osteon perimeter producing an error of 8.07 years for Greek-Cypriots. This research demonstrates the feasibility of quantitative bone histology to estimate age, obtaining errors rates in accordance with macroscopic ageing techniques. Sex and sample population differences need further investigation and inter-population variation in remodelling rates is suggested. Moreover, this study contributes to the creation of population-specific standards for Cretans and Greek-Cypriots.

  相似文献   
29.

Objective:

Determine the prevalence and compare some genetic markers involved in addictive behavior in a group of addicts to derivative of coca (cocaine/crack) or heroin and a control group of non-addicted people matched for gender, age and ethnicity.

Methods:

A 120 addicts and 120 non-addicts Colombian male were surveyed and genotyped for 18 polymorphism of the OPRM1, DRD2, DRD4, SLC6A3, SLC6A4, ABCB1, DβH and CYP2B6 genes. For the identification of alleles markers were used mini-sequencing and fragment multiplex PCR techniques; ethnicity of cases and controls was analyzed with 61 AIMs.

Results:

The age of onset use of heroin or coca derivatives (cocaine/crack) was 16.5±6 years and 99.2% of them consume several illicit drugs. It showed that controls and addicts belong to the same ethnic group. Significant differences between addicts and controls in relation to schooling, marital status, social security family history of substance abuse (p <0.001), Int8-VNTR SLC6A3 gene (p= 0.015) and SNP 3435C>T ABCB1 gene (p= 0.001) were found.

Conclusion:

The present results indicate that the VNTR- 6R polymorphism of the gene SLC6A3 and the genotype 3435CC in the ABCB1 gene, are both associated with addictive behavior to heroin or cocaine.  相似文献   
30.
Urothelial bladder cancer (UBC) is a heterogeneous type of disease. It is urgent to screen biomarkers of tumour aggressiveness in order to clarify the clinical behaviour and to personalize therapy in UBC patients. Raf kinase inhibitory protein (RKIP) is a metastasis suppressor, and its downregulation is associated with metastatic events in an increasing number of solid tumours. We evaluated the clinical and prognostic significance of RKIP expression in patients with high risk of progression UBC. Using immunohistochemistry, we determined RKIP expression levels in a series of 81 patients with high-grade pT1/pTis or muscle-invasive UBC. Staining of CD31 and D2-40 was used to assess blood and lymphatic vessels, in order to distinguish between blood and lymphatic vessel invasion (LVI). We found that 90 % of pT1/pTis tumours, 94 % of non-muscle invasive papillary tumours and 76 % of the cases without LVI occurrence expressed RKIP in >10 % of cells. In this group, we observed a subgroup of tumours (42 %) in which the tumour centre was significantly more intensely stained than the invasion front. This heterogeneous pattern was observed in 63 % of the cases with LVI. Low RKIP expression was associated with poorer 5-year disease-free and overall survival rates, and remained as an independent prognostic factor for disease-free survival. Loss of RKIP expression may be an important prognostic factor for patients with high risk of progression bladder cancer.  相似文献   
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