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91.
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93.
Objective  To quantify participants' experiences of obtaining and giving information about disorders of sex development (DSD).
Design  Cross-sectional survey study that asked people about their current and past experiences relating to DSD disclosure.
Setting  A large tertiary referral centre for DSD management in the UK.
Population  One hundred of 126 people with a confirmed diagnosis of DSD who were invited to participate in the study formed the usable sample.
Methods  All people who attended clinic for follow-up during the study period and members of a patient support group whose annual meeting fell within the study period were asked to complete the Middlesex Communication Survey.
Main outcome measures  The Middlesex Communication Survey.
Results  Younger participants were more likely to report having been appropriately informed about their diagnosis than older people. Nearly half of the former had been fully informed about their diagnosis by age 15 years, compared with 0% of the older age group. In terms of information sharing, mothers were most likely to be the person with whom the participant had shared (almost/all) DSD information (74%), followed by current partners (71%). Information relating to genital surgery, presence of testes and clitoral anomalies were the least likely aspects to have been unambiguously shared with even the most informed person.
Conclusions  Our results suggest that difficulties in obtaining DSD information from care providers were common, and that communication has improved for younger participants. The study also confirmed that many people with DSD continue to struggle with confiding, even in those closest to them, about aspects of their diagnosis. Care protocol needs to centralise psychological adaptation, which should also be a primary focus for future research.  相似文献   
94.
Maciejewski  JP; Selleri  C; Sato  T; Anderson  S; Young  NS 《Blood》1996,88(6):1983-1991
We examined the stem cell compartment of patients with acquired aplastic anemia (AA) using the long-term culture-initiating cell assay (LTC-IC), in parallel with measurements of CD34+ cells and mature hematopoietic progenitors. Secondary colonies from cells surviving 5 weeks of long-term bone marrow culture (LTBMC) were determined for the peripheral blood (PB) of 68 AA patients and 13 normal controls and for BM of 49 AA patients and 14 controls; because of low cell numbers, formal limiting dilution analysis could only be performed in 10 patients. The relationship of cell input in LTBMC and the output of secondary colonies was linear, allowing quantification of LTC-IC number from bulk cultures. Secondary colony formation was markedly abnormal in severe AA. In contrast to 7.8 colony-forming cells (CFC)/10(5) mononuclear cells in normal BM and 0.14 CFC/10(5) normal PB mononuclear cells, patients with severe disease showed 0.024 CFC/10(5) in BM and 0.0068 CFC/10(5) in PB. Under limiting dilution conditions, patients' cells also showed markedly lower colony-forming ability. In contrast to 4.3 +/- 1 colonies/normal LTC-IC, we obtained only 1.27 +/- 0.09 and 2.0 +/- 0.35 colonies from BM of acute and recovered cases, respectively. These values were used to extrapolate LTC-IC numbers from secondary colony formation in suspension cultures. In PB, calculated LTC-IC were decreased 7.4-fold in new and relapsed severe AA and 2.8- fold in recovered AA. In BM, LTC-IC were decreased 10-fold in new and relapsed AA and sixfold in recovered cases. Compared with measurements obtained on presentation, LTC-IC were lower in post-treatment samples from patients who had failed to recover after intensive immunosuppression and relatively higher in cases at relapse. In recovered patients, LTC-IC number increased but remained below the normal range in 20 of 25. In patients studied serially for 3 to 12 months after treatment, LTC-IC numbers remained stable but low. LTC-IC number correlated with concurrently determined CD34+ cell number and primary hematopoietic colony formation. These results indicate that stem cell numbers, as quantitated by the LTC-IC assay, are markedly diminished in number in all severe AA. Additionally, the function of the stem cell or the stem cell compartment in AA is also abnormal, as inferred from the low clonogenic potential in secondary colony assays. Early hematologic improvement in some patients occurs without increasing numbers of LTC-IC, and a minority of recovered cases show apparent repopulation of the LTC-IC compartment years after treatment.  相似文献   
95.
Hematopoiesis appears to be regulated, in part, by a balance between extracellular positive and negative growth signals. Transforming growth factor beta-1 (TGF-beta 1) has been shown to be a negative regulator of primitive hematopoietic cells. This study examined the direct effect of TGF-beta 1 on the proliferation and differentiation of long-term repopulating hematopoietic stem cells (LTR-HSC) in vitro. We previously reported a cell fractionation approach that includes the selection of low Hoescht 33342/low Rhodamine 123 (low Ho/Rh) cell fractions that are highly enriched for long-term repopulating cells (LTR-HSC) and also clone to a very high efficiency in the presence of stem cell factor (SCF) + interleukin-3 (IL-3) + IL-6: 90% to 100% of individually cultured low Ho/Rh cells formed high proliferative potential clones. This high cloning efficiency of an LTR-HSC enriched cell population enabled proliferation inhibition studies to be more easily interpreted. In this report, we show that the continuous presence of TGF-beta 1 directly inhibits the cell division of essentially all low Ho/Rh cells (in a dose-dependent manner) during their 0 to 5th cell division in vitro. Therefore, it follows that TGF-beta 1 must directly inhibit the proliferation of LTR-HSC contained within these low Ho/Rh cells. The time required for some low Ho/Rh cells to undergo their first cell division in vitro was also prolonged in the presence of TGF-beta 1. Furthermore, when low Ho/Rh cells were exposed to TFG-beta 1 for varying lengths of time before neutralization of the TGF-beta 1 by monoclonal antibody, the ability to form macroclones was markedly decreased after approximately 4 days of TGF-beta 1 exposure. In addition, 1 to 10 ng/mL of TGF-beta 1 resulted in a maintenance of high proliferative potential-colony-forming cell (HPP-CFC) during 8 days of culture compared with loss of HPP-CFC in cultures with no added TGF- beta 1. In conclusion, this study shows that TGF-beta 1 directly inhibits the initial stages of proliferation of LTR-HSC and appears to slow the differentiation of daughter cells of low Ho/Rh cells.  相似文献   
96.
Flake  AW; Harrison  MR; Adzick  NS; Zanjani  ED 《Blood》1987,70(2):542-545
To gain insight into the mammalian liver to kidney erythropoietin (Ep) switch, we heterotopically transplanted livers from preswitch, switched, and postswitch fetal and newborn lambs into normal adult sheep. Recipients' serum Ep and circulating reticulocyte levels were serially determined until rejection of the graft and compared with identical samples from sham-operated control adult ewes. Transplantation of preswitch and switched fetal livers caused an impressive rise in recipients' serum Ep activity and provoked a corresponding increase in reticulocytosis. In contrast, Ep activity and reticulocyte counts did not change from preoperative levels in adult ewes transplanted with postswitch livers or in the sham-operated controls. The production of Ep by the preswitch fetal liver in the adult environment was not dependent on the presence or absence of host kidneys and was stimulated by anemic hypoxia. These results suggest that the fetal liver is capable of producing relatively large amounts of Ep activity, and the production of Ep can be maintained in the adult environment in the presence of functional adult kidneys. This argues against suppression of liver Ep production by renal Ep, or some other factor in the postnatal environment, and suggests that the liver to kidney switch of Ep production during ontogeny may represent a genetically determined event.  相似文献   
97.
Molecular analysis of cutaneous B- and T-cell lymphomas   总被引:3,自引:0,他引:3  
Among extranodal non-Hodgkin's lymphomas, primary cutaneous lymphomas (CLs) represent a consistent group of B- and T-cell malignancies. We investigated the arrangement of Ig and T-cell receptor (TCR) genes, together with the involvement of several oncogenes and the tumor- suppressor gene p53, in a panel of primary cutaneous B- and T-cell lymphomas (CBCLs and CTCLs). Southern blot analysis was performed to detect rearrangements of the Ig, c-myc, bcl-1, bcl-2, bcl-3, bcl-6, and the NFKB2/lyt-10 genes in 52 cases of CBCLs and of the TCR, bcl-3, and NFKB2/lyt-10 genes in 38 cases of CTCLs. tal-1 gene deletions were analyzed in CTCLs by means of polymerase chain reaction (PCR). p53 gene mutations were assayed using PCR, single-strand conformation polymorphism analysis, and direct DNA sequencing in CBCL and CTCL cases. Clonal rearrangements of Ig genes or oncogenes were found in 25 of the 52 CBCLs. In particular, we detected rearrangements of the bcl-1 locus (2 cases), the bcl-2 gene (2 cases), the NFKB2/lyt-10 gene (2 cases), and the bcl-6 gene (1 case); interestingly, 4 of these cases showed a germline arrangement of the Ig genes. Clonal rearrangements of TCR genes were detected in 37 of the 38 CTCLs. Rearrangements of the NFKB2/lyt-10 gene were present in 2 cases and tal-1 gene deletions in 3 CTCL cases; p53 gene mutations were detected in 1 CTCL case. Overall, our data indicate that (1) clonal rearrangement of Ig genes is frequently undetectable by means of Southern blot in CBCLs (60%); (2) genetic lesions are involved in a limited but significant fraction of primary CLs showing a molecular marker of clonality (13/62; 20%); and (3) rearrangements of the bcl-1, bcl-2, or bcl-6 loci, associated with specific subsets of nodal lymphoid neoplasias, are rarely observed in CBCLs. Moreover, our results suggest that tal-1 gene deletions may play a pathogenetic role in non-acute T-cell malignancies and that, in the context of lymphoid malignancies, CLs may represent a favorable target for the possible oncogenic potential of the NFKB2/lyt-10 gene.  相似文献   
98.
Selleri  C; Maciejewski  JP; Sato  T; Young  NS 《Blood》1996,87(10):4149-4157
Clinical and laboratory studies have suggested involvement of interferon-gamma (IFN-gamma) in the pathophysiology of aplastic anemia. T cells from aplastic anemia (AA) patients secrete IFN-gamma in vitro, activated cytotoxic lymphocytes infiltrate aplastic bone marrow (BM), and IFN-gamma mRNA, not detected in normal BM, is present in BM from most AA patients. Many patients respond to immunosuppressive therapy with antithymocyte globulin and cyclosporine. Using long-term BM cultures (LTBMC) as a tissue culture model of hematopoiesis, we show that IFN-gamma is a potent inhibitor in the long-term culture- initiating cell (LTC-IC) assay, the best in vitro surrogate test for human hematopoietic stem cells, as well as of the output of committed progenitor cells (colony-forming unit-granulocyte-macrophage [CFU-GM] and burst-forming unit-erythroid [BFU-E]). In LTBMC, continuous addition of relatively high IFN-gamma concentrations (1,000 U/mL weekly or 200 U/mL every 2 days) was required for inhibition of secondary colony formation, a measure of LTC-IC number and clonogenicity. To mimick local production of IFN-gamma, human stromal cells were engineered by retroviral-mediated gene transfer to express a transduced IFN-gamma gene. IFN-gamma secreted by stromal cells was far more potent than exogenous IFN-gamma in its effects in the LTC-IC assay. For purified CD34+ cells culture in the presence of IFN-gamma stroma dramatically reduced secondary colony numbers as well as production of CFU-GM and BFU-E. Supernatants from these cultures contained only about 20 U/mL of IFN-gamma; this quantity of cytokine, when added to LTBMC, had little effect on hematopoiesis. The mechanism of hematopoietic suppression was related to the inhibition of cell cycle progression and induction of apoptosis of CD34+ cells. There was no apparent effect of local low-level IFN-gamma production on stromal cell function, as reflected in cell morphology, cell surface phenotype, or expression of hematopoietic growth factor genes. LTBMC with genetically altered stromal cells offers an in vitro model of immune suppression of hematopoiesis in AA and may be helpful in testing certain therapeutic modalities. We infer from our data that local production of low levels of inhibitory cytokine is sufficient to markedly inhibit hematopoiesis and to destroy stem cells and more mature progenitor cells.  相似文献   
99.
100.

Introduction

Reoperative parathyroidectomy is required when there is persistent or recurrent hyperparathyroidism following the initial surgery (at least 5% of parathyroidectomies nationally). By convention, ‘persistent disease’ is defined as the situation where the patient has not been cured by the first operation. The term ‘recurrent hyperparathyroidism’ is used when the patient was confirmed to be biochemically cured for six months from the first operation but has hyperparathyroidism after this date. Reoperative surgery is associated with higher rates of postoperative complications as well as a greater rate of failure to cure. The aim of our study was to review our departmental experience of reoperative parathyroidectomy, with a view to identify patterns of disease persistence and recurrence.

Methods

Using a departmental database, patients were identified who had undergone reoperative parathyroidectomy between 2006 and 2014. All the pre, intra and postoperative information was documented including the operative note so as to record the location of the abnormal parathyroid gland found at reoperation.

Results

Almost two-thirds (63%) of patients had negative, equivocal or discordant conventional imaging so secondary investigative tools were required frequently. The majority of abnormal glands were found in eutopic locations. The most common locations for ectopic glands were intrathyroidal, mediastinal and intrathymic. A third (33%) of the patients had multigland disease and over a quarter (28%) had coexisting thyroid disease.

Conclusions

Persistent hyperparathyroidism represents a challenging patient subgroup for which access to all radiological modalities and intraoperative parathyroid hormone monitoring are required. Patient selection for reintervention is a key determinant in the reoperation cure rate.  相似文献   
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