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101.
Graft failure is associated with a high mortality rate. To date, regimens invoked for second transplants have resulted in inconsistent engraftment with high transplant-related mortality (TRM). We here report 16 consecutive patients, aged 4-59 years, who received second HSCT (HSCT-2) at a median of 45 days following primary or secondary failure of an initial unmodified (N = 3) or T cell-depleted (TCD) (N = 13) HSCT (HSCT-1). HSCT-1 was administered after myeloablative total body irradiation (TBI)- or alkylator-based conditioning for acute leukemias (N = 7), MDS (N = 6), CML (N = 2), and Fanconi anemia (N = 1). All patients experienced 1 or more infectious complications between HSCT-1 and HSCT-2, and 10 patients had active infections at the time of HSCT-2. Cytoreduction regimens used for HSCT-2 included fludarabine (Flu) in combination with cyclophosphamide (CTX) (N = 9), or thiotepa (Thio) (N = 5). In addition, 1 patient received Flu alone and 1 patient Thio combined with CTX. Antithymocyte globulin (ATG) (N = 11) or Alemtuzumab (N = 3) was added pretransplant to prevent rejection. For HSCT-2, donors included HLA-matched (N = 3) or mismatched (N = 8) related, or matched (N = 2) or mismatched (N = 3) unrelated donors. The primary graft donor was used in 6 of 16 cases. The grafts administered were unmodified peripheral blood stem cell transplantation (PBSCT) (N = 5) or bone marrow transplantation (BMT) (N = 3), TCD PBSCT (N = 8). All patients achieved engraftment at a median of 12 days and evaluable patients achieved complete donor chimerism. Six patients are alive with a median follow-up of 49 months, including 4/9 conditioned with Flu/CTX. In this series, outcome was statistically superior for younger patients (相似文献   
102.
Loss of heterozygosity (LOH) in the region of 10q23.3 has been associated with multiple tumors, including glioblastoma multiforme, melanoma, endometrial carcinoma, and prostate carcinoma. The tumor suppressor gene, PTEN/MMAC1, is also located in this region, and, in addition to other tumor types (eg, glioblastoma multiforme, endometrial, and melanoma), PTEN/MMAC1 mutations have been found in prostate cancer cell lines, xenografts, and hormone refractory prostate cancer tissue specimens. The aim of this study was to evaluate LOH at 10q23.3 as a marker of cancer progression in node-positive prostate cancer. Genetic alterations in the region of 10q23.3 were assessed in 23 node-positive (pT2-3, N+) and 44 node-negative prostate (pT2-3, N0) cancers with D10S532, D10S1687, D10S541, and D10S583 flanking polymorphic genetic markers; PTENCA, a genetic marker within PTEN/MMAC1, was also tested. Using DNA from paired normal and microdissected tumor samples, LOH at microsatellite loci was determined after polymerase chain reaction amplification. LOH in at least 1 marker was identified in 14% (6 of 44) of lymph node-negative and 43% (10 of 23) of lymph node-positive prostate cancers (chi-square test, P = .007). This increase in genetic alterations in node-positive prostate cancer suggests that 10q23.3 is a marker for metastatic progression.  相似文献   
103.
Background and aimThe aim of this study is to evaluate whether the long-term (≥4 weeks) use of proton pump inhibitors (PPIs) is a risk factor for intubation requirement and mortality in patients hospitalized for COVID-19.Materials and methods In this multicentric retrospective study, a total of 382 adult patients (≥18 years of age) with confirmed COVID-19 who were hospitalized for treatment were enrolled. The patients were divided into two groups according to the periods during which they used PPIs: the first group included patients who were not on PPI treatment, and the second group included those who have used PPIs for more than 4 weeksResultsThe study participants were grouped according to their PPI usage history over the last 6 months. In total, 291 patients did not use any type of PPI over the last 6 months, and 91 patients used PPIs for more than 4 weeks. Older age (HR: 1.047, 95% CI: 1.026–1.068), current smoking (HR: 2.590, 95% CI: 1.334–5.025), and PPI therapy for more than 4 weeks (HR: 1.83, 95% CI: 1.06–2.41) were found to be independent risk factors for mortalityConclusionThe results obtained in this study show that using PPIs for more than 4 weeks is associated with negative outcomes for patients with COVID-19. Patients receiving PPI therapy should be evaluated more carefully if they are hospitalized for COVID-19 treatment.  相似文献   
104.
Specific and major histocompatibility complex (MHC)-restricted T-cell recognition of antigenic peptides is based on interactions of the T-cell receptor (TCR) with the MHC alpha helices and solvent exposed peptide residues termed TCR contacts. In the case of MHC class II-presented peptides, the latter are located in the positions p2/3, p5 and p7/8 between MHC anchor residues. For numerous epitopes, peptide substitution studies have identified the central residue p5 as primary TCR contact characterized by very low permissiveness for peptide substitution, while the more peripheral positions generally represent auxiliary TCR contacts. In structural studies of TCR/peptide/MHC complexes, this has been shown to be due to intimate contact between the TCR complementarity determining region (CDR) three loops and the central peptide residue. We asked whether this model also applied to two HLA-DR presented epitopes derived from an antigen targeted in type 1 diabetes. Large panels of epitope variants with mainly conservative single substitutions were tested for human leukocyte antigen (HLA) class II binding affinity and T cell stimulation. Both epitopes bind with high affinity to the presenting HLA-DR molecules. However, in striking contrast to the standard distribution of TCR contacts, recognition of the central p5 residue displayed high permissiveness even for non-conservative substitutions, while the more peripheral p2 and p8 TCR contacts showed very low permissiveness for substitution. This suggests that intimate TCR interaction with the central peptide residue is not always required for specific antigen recognition and can be compensated by interactions with positions normally acting as auxiliary contacts.  相似文献   
105.
Pompe disease is a rare autosomal recessive disorder characterized by the deficiency of acid α-glycosidase resulting in lysosomal accumulation of glycogen. The late-onset disease form is characterized by progressive skeletal and respiratory muscle dysfunction. In addition to the recently introduced enzyme replacement therapy (ERT), treatments such as protein-enriched diet and exercise training have been proposed, although little is known about their effectiveness on the physical condition of such patients. Aim of the present study was to investigate the effect of exercise training on muscular strength and body composition in five patients with late-onset Pompe disease receiving ERT. All subjects followed a 20 week lasting program of supervised aerobic and progressive resistance exercise training. Before and after the training period, body composition was determined with dual X-ray absorptiometry and isometric muscular strength was measured with a specialized load transducer. Functional capacity was assessed using the 6-min shuttle walk test. A significant increase in muscular strength (15–50% at various body parts, p < 0.05) and 6-minute walking distance (203.8 ± 177 m before vs. 248.2 ± 184 m after, p < 0.01) was observed after training, whereas total and lower extremities lean body mass did not change significantly. These results suggest that exercise training has a positive effect on muscular strength and functional capacity in patients on ERT with late-onset Pompe disease.  相似文献   
106.
Background. β-Blockers cause a psoriasiform eruption. We investigated the skin effects of systemic propranolol in a formal protocol. Methods. Propranolol, 0.1 mg/day, was used systemically by gavage in eight albino guinea pigs. Normal saline was given to another group of seven guinea pigs. Results. Propranolol produced psoriasiform lesions in five of seven guinea pigs on the 30th day. Biopsies showed acanthosis, parakeratosis, microabscesses, and cellular infiltration of upper dermis. Topical application of propranolol did not produce clinical psoriasiform changes, while acanthosis and papillomatosis was observed in six of the six guinea pigs. Conclusions. Systemically given propranolol can lead to psoriasis-like lesions, which might be due to a serum factor.  相似文献   
107.

Purpose

Topical therapy (TT) for upper tract urothelial carcinoma (UTUC) has been explored as a kidney sparing approach to treat carcinoma in situ (CIS) and as adjuvant for endoscopically treated Ta/T1 tumors. In bladder cancer, data support use of salvage TT for repeat induction. We investigate the outcomes of salvage TT for UTUC in patients ineligible for or refusing nephroureterectomy.

Methods

A single-center retrospective review on patients receiving salvage TT via percutaneous nephrostomy tube or cystoscopically placed ureteral catheters was performed. Primary outcome was response to therapy based on International Bladder Cancer Group criteria.

Results

51 patients with 58 renal units (RUs) received TT. Of these, 17 patients with 18 RUs received the second-line TT, with a median follow-up of 36.5 months (IQR 24.5–67 months). 44% (8/18) received salvage TT for refractory disease and 56% (10/18) as reinduction. 5 RUs with CIS were unresponsive to initial TT and went on to receive salvage TT, of which 20% (1/5) responded. 13 RUs recurred or relapsed following initial TT and received salvage TT for papillary tumors, with 62% (8/13) responding.

Conclusion

Our data provide preliminary clinical rationale for the second-line TT for refractory and recurrent, endoscopically managed papillary UTUC in patients ineligible for or refusing nephroureterectomy. However, refractory upper tract CIS appears to have poor response to salvage TT.
  相似文献   
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