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1.
A factor of nominal molecular weight 6K–10K Daltons, isolated from bovine aorta, has previously been shown to inhibit neovascularization and tumor growth in vivo and the growth of some tumor cells as well as endothelial cells in culture. This factor, termed A-10, was tested alone and in combination with Adriamycin against TA3Ha mammary adenocarcinoma cells in tissue culture. It was found to have cytotoxicity additive to that of Adriamycin in inhibiting the growth of these cells. In vitro and animal studies show that the sequence of Adriamycin A-10 is superior to either agent alone in delaying the appearance of palpable tumors after subcutaneous injection of 105 pre-treated tumor cells in the tail of strain A mice. While the growth rate of the primary tumor was not affected by such treatment, survival was prolonged to a greater degree by the this sequence than by either of these agents used alone. A-10 treatment reduced the number of metastases to the adrenal gland but not to lung, liver, or lymph nodes. It did, however, reduce the size of metastases to para-aortic lymph nodes.  相似文献   
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BACKGROUND: Bacteremia occurs frequently after intestinal transplantation (ITx) in children. During our initial experience with this procedure, we noted that bacteremic episodes tended to occur simultaneously with the presence of rejection and/or gastrointestinal (GI) posttransplant lymphoproliferative disease (PTLD). AIM: To document the association of bacteremia with rejection and GI PTLD in pediatric ITx recipients. METHODS: Retrospective analysis of all medical records from 62 children who underwent ITx between July 1990 and January 1998 at Children's Hospital of Pittsburgh. A bacteremic episode was defined as two positive blood cultures from different sites at the same time or from the same site at different times. Rejection and PTLD were defined using previously published criteria. RESULTS: A total of 39/62 ITx recipients had 133 blood stream infections (2.1 episodes/patient) including 121 episodes of bacteremia and 12 of fungemia. Enteric organisms were the most frequently recovered pathogens (Gram negative rods, n=76; enterococci, n=36). Enteric organisms were recovered as a single organism (n=57), with another enteric bacteria (n=23), or with coagulase negative staphylococci (CONS) (n=24). CONS were recovered as a single organism on 21 occasions. An obvious source of bacteremia was not found for 115/121 episodes. Endoscopy was performed for 107 of the 115 bacteremia episodes; an abnormal histology was identified in 74 revealing rejection (n=36), GI PTLD (n=21), or both (n=17). When endoscopy showed GI pathology, enteric organisms alone or in combination with CONS were recovered on 63/107 occasions, although CONS were recovered alone only 11 times. CONCLUSIONS: Bacteremia accompanies GI rejection and intestinal PTLD in ITx recipients. Endoscopy should be performed to inspect the allograft when bacteremia occurs without an obvious source in these patients. This is especially true for patients with bacteremia due to enteric organisms.  相似文献   
3.
BACKGROUND: In this report, we compare the long-term outcome of pediatric liver transplantation (LTx) patients maintained with tacrolimus-based and with cyclosporine (CsA)-based immunosuppressive therapy. We examine long-term patient and graft survival, the incidence of rejection, and immunosuppression-related complications. METHOD: There were 233 consecutive primary LTx in children (ages <18 years) performed between October 1989 and December 1994 with tacrolimus-based immunosuppressive therapy (Group I). These were compared with 120 consecutive primary LTx performed with CsA-based immunosuppressive therapy between January 1988 and October 1989(Group II). Children in both groups were followed until July 1999. Mean follow-up was 91.41+/-17.7 months (range 55.6-117.8) for Group I, and 128+/-6.1 months (range 116.7-138.6) for Group II. RESULTS: At 9 years of follow-up, actuarial patient and graft survival were significantly improved (patient survival 85.41% in Group I vs. 63.8% in Group II, P=0.0001; graft survival Group I 78.9% vs. 60.8% Group II, P=0.0003) and the rate of re -transplantation was significantly lower among patients in Group I (12% in Group I vs. 22.5% in Group II P=0.01). Children in Group I also experienced a significantly reduced incidence of acute rejection (0.97 per patient Group I vs. 1.5 per patient Group II P=0.002) and significantly less steroid resistant acute rejection episodes (3.1% in Group I vs. 8.6% in Group II P=0.0001). The mean steroid dose was significantly lower in Group I compared with Group II at all time points (P=0.0001) after LTx. Freedom from steroid was also significantly higher in Group I compared with Group II at all time points after LTx (ranging from 78% to 84% in Group I and 9% to 32% in Group II during a 1- to 7-year posttransplant period P=0.0001). The rate of hypertension was significantly lower in Group I than Group II (P=0.0001), and the severity of hypertension (need for more than one anti-hypertensive medication) was also significantly lower in Group I than Group II (P=0.0001). Although the rate of posttransplant lymphoproliferative disorder (PTLD) was not significantly different (13.7% Group I vs.8.3% Group II, P=0.13), the survival after PTLD was significantly better for Group I at 81.2% than for Group II at 50% after 5 years (P=0.034). Conclusion. The results suggest that tacrolimus-based therapy provides significant long-term benefit to pediatric LTx patients, evidenced by significantly improved patient and graft survival, reduced rate of rejection, and hypertension with lower steroid doses.  相似文献   
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We report on tacrolimus-associated posterior reversible encephalopathy syndrome with the previously unreported finding of leptomeningeal enhancement occurring separate from the site of parenchymal magnetic resonance signal abnormality. Recognition of this atypical finding as a noninfectious cause of leptomeningeal enhancement may assist those caring for patients affected by posterior reversible encephalopathy syndrome.  相似文献   
7.
Applying principles of user‐centered design, we iteratively developed and tested the prototype of TPP, an mHealth application to promote medication adherence and enhance communication about medication management between adolescents and primary caregivers. A purposive sample of seven adolescent solid organ transplant recipients who were ≥one yr post‐transplant and their primary caregivers participated. Participants completed up to three face‐to‐face laboratory usability sessions, a 6‐week field test, and a debriefing session. Primary caregivers participated in an additional usability telephone session. Participants completed usability and satisfaction measures. Sample included liver (n = 4), heart (n = 2), and lung (n = 1) recipients aged 11–18 yr (57% were female, 86% were Caucasian), and nine primary caregivers aged 42–61 yr (88.9% were parents, 88% were female, 88% were Caucasian). Ninety percent of the adolescents endorsed the graphs or logs of missed/late medication dosing as useful and 100% endorsed the remaining features (e.g., medication list, dose time reminders/warnings) as useful. All adolescents expressed interest in using TPP for monitoring medications and satisfaction with the automatic messaging between adolescent and caregiver versions of the application. Adolescents unanimously found TPP easy to use. TPP shows promise as an mHealth adherence tool.  相似文献   
8.
Sitnicka  E; Lin  N; Priestley  GV; Fox  N; Broudy  VC; Wolf  NS; Kaushansky  K 《Blood》1996,87(12):4998-5005
In this study, we explored whether thrombopoietin (Tpo) has a direct in vitro effect on the proliferation and differentiation of long-term repopulating hematopoietic stem cells (LTR-HSC). We previously reported a cell separation method that uses the fluorescence-activated cell sorter selection of low Hoescht 33342/low Rhodamine 123 (low Ho/low Rh) fluorescence cell fractions that are highly enriched for LTR-HSC and can reconstitute lethally irradiated recipients with fewer than 20 cells. Low Ho/low Rh cells clone with high proliferative potential in vitro in the presence of stem cell factor (SCF) + interleukin-3 (IL-3) + IL-6 (90% to 100% HPP-CFC). Tpo alone did not induce proliferation of these low Ho/low Rh cells. However, in combination with SCF or IL-3, Tpo had several synergistic effects on cell proliferation. When Tpo was added to single growth factors (either SCF or IL-3 or the combination of both), the time required for the first cell division of low Ho/low Rh cells was significantly shortened and their cloning efficiency increased substantially. Moreover, the subsequent clonal expansion at the early time points of culture was significantly augmented by Tpo. Low Ho/low Rh cells, when assayed in agar directly after sorting, did not form megakaryocyte colonies in any growth condition tested. Several days of culture in the presence of multiple cytokines were required to obtain colony-forming units-megakaryocyte (CFU-Mk). In contrast, more differentiated, low Ho/high Rh cells, previously shown to contain short- term repopulating hematopoietic stem cells (STR-HSC), were able to form megakaryocyte colonies in agar when cultured in Tpo alone directly after sorting. These data establish that Tpo acts directly on primitive hematopoietic stem cells selected using the Ho/Rh method, but this effect is dependent on the presence of pluripotent cytokines. These cells subsequently differentiate into CFU-Mk, which are capable of responding to Tpo alone. Together with the results of previous reports of its effects on erythroid progenitors, these results suggest that the effects of Tpo on hematopoiesis are greater than initially anticipated.  相似文献   
9.
For the first time, the Canadian Hypertension Education Program has studied the evidence supporting blood pressure control in people requiring renal replacement therapy for end-stage kidney disease, including those on dialysis and with renal transplants. According to the Canadian Organ Replacement Registry’s 2008 annual report, there were an estimated 33,832 people with end-stage renal disease in Canada at the end of 2006, an increase of 69.7% since 1997. Of these, 20,465 were on dialysis and 13,367 were living with a functioning kidney transplant. Thus, it is becoming more likely that primary care practitioners will be helping to care for these complex patients. With the lack of large controlled clinical trials, the consensus recommendation based on interpretation of the existing literature is that blood pressure should be lowered to below 140/90 mmHg in hypertensive patients on renal replacement therapy and to below 130/80 mmHg for renal transplant patients with diabetes or chronic kidney disease.  相似文献   
10.
Aim: The aim of the student is to assess whether adolescents with type 1 diabetes mellitus (T1DM) in Italy differ from their healthy peers in regard to risky behaviour. Methods: Data were collected from 215 patients, aged 14 ± 2 years with a mean disease duration of 7 ± 5 years. The control group was comprised of 464 healthy adolescents recruited among high school students. Each patient completed an anonymous confidential questionnaire to determine the prevalence of sexual behaviour, alcohol and tobacco consumption, illicit drug use, and, among patients with diabetes and frequency of mismanagement related to diabetes care. Results: Compared with controls, subjects with diabetes showed a similar rate of sexual intercourse among males and lower rates among females (34.8% vs 35.5%, p NS and 29.4% vs 41.4%, p < 0.05, respectively). Males in the diabetes group reported a higher rate of tobacco use, whereas females showed similar or higher rates of use for every illicit drug studied. Among patients with diabetes, those who are engaged in risky behaviour showed a higher rate of treatment mismanagement (76% vs 34%, p < 0.01). Conclusion: Adolescents with T1DM are as likely as their healthy peers to engage in risky behaviour, indicating the potential benefit of anticipatory guidance concerning glycaemic control and increased risk of acute and chronic complications.  相似文献   
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