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1.
The aim of this experiment was to test a safe, noninvasive method for necessary, accurate diagnosis of early allograft rejection. Heart-lung allograft was performed heterotopically using Brown Norway (BN) rats as the donor and Lewis (LEW) rats as the recipient. T cell suspensions were prepared from lymphnodes of specifically sensitized LEW rats that had acutely rejected full-thickness BN skin graft. Cell count was adjusted 50 x 10(6) cells/ml. The suspension was incubated in vitro with 111I oxide (1 m Ci-ml). An aliquot of labeled cell suspension containing 40 x 10(6) cells and a total radioactivity of 200 mCi was administered intravenously to each animal 3 and 6 days after heart-lung transplant. The traffic of T cells was followed in vivo and in isolated organs under large field view gamma camera. The gamma camera revealed radioactivity on the graft starting Postoperative Day 5 when the heart was actively beating; no radioactivity was revealed at the site of the isografted organs. The histology showed mild to moderate cellular infiltration parallel to the grade of radioimaging intensity. The injection of indium-labeled presensitized T cells was able to detect the rejection process in an early phase when there are no clinical symptoms of rejection and/or the rejection cascade can be reversed. These results suggest that a similar method can be used in human organ transplantation for early diagnosis of rejection.  相似文献   
2.
While a dural sinus thrombosis (DST), is a well-known consequence of the use of oral contraceptives, the role of hormone replacement therapy (HRT) in DST was not previously evaluated. We report two postmenopausal women, presenting with DST under HRT. Antiphospholipid antibodies in one case and borderline protein S deficiency in another were diagnosed. Only five cases of DST under HRT were previously reported and in two of them additional prothrombotic risk factors were found. According to these and previous cases, HRT is not an independent risk factor for DST.  相似文献   
3.
It was shown previously that chronic exposure to opiate agonists increases adenylyl cyclase (AC) activity, a phenomenon termed AC superactivation (or supersensitization). More recently, we showed that acute Gi/o-coupled receptor activation inhibits the activity of several AC isozymes, including Ca2+/calmodulin-stimulated AC-I and -VIII, whereas chronic receptor activation induces their superactivation. Here, we report that both acute μ-opioid receptor-induced inhibition and chronic induced superactivation of AC-I and -VIII are pertussis toxin sensitive. In addition, we show that proteins that interfere with the activity of {ie195-2} subunits ({ie195-3} scavengers) strongly attenuate the acute inhibition of AC-I and -VIII and the superactivation of AC-I, and abolish the superactivation of AC-VIII. Based on these results, we suggest that {ie195-4} is involved in the acute inhibition and chronic agonist-induced superactivation of AC types I and VIII.  相似文献   
4.
BackgroundIncreasing cancer incidence among children alongside improved treatments has resulted in a growing number of pediatric cancer survivors. Despite childhood cancer survivors’ exposure to various factors that compromise kidney function, few studies have investigated the association between childhood cancer and future kidney disease.MethodsTo assess the risk of ESKD among childhood cancer survivors, we conducted a nationwide, population-based, retrospective cohort study that encompassed all Israeli adolescents evaluated for mandatory military service from 1967 to 1997. After obtaining detailed histories, we divided the cohort into three groups: participants without a history of tumors, those with a history of a benign tumor (nonmalignant tumor with functional impairment), and those with a history of malignancy (excluding kidney cancer). This database was linked to the Israeli ESKD registry to identify incident ESKD cases. We used Cox proportional hazards models to estimate the hazard ratio (HR) of ESKD.ResultsOf the 1,468,600 participants in the cohort, 1,444,345 had no history of tumors, 23,282 had a history of a benign tumor, and 973 had a history of malignancy. During a mean follow-up of 30.3 years, 2416 (0.2%) participants without a history of tumors developed ESKD. Although a history of benign tumors was not associated with an increased ESKD risk, participants with a history of malignancy exhibited a substantially elevated risk for ESKD compared with participants lacking a history of tumors, after controlling for age, sex, enrollment period, and paternal origin (adjusted HR, 3.2; 95% confidence interval, 1.3 to 7.7).ConclusionsChildhood cancer is associated with an increased risk for ESKD, suggesting the need for tighter and longer nephrological follow-up.  相似文献   
5.
Tomer A  Eliason G 《Death Studies》1996,20(4):343-365
An integrative, comprehensive model of death anxiety is presented. The model postulates three immediate antecedents of death anxiety: past-related regret, future-related regret, and meaningfulness of death. Past-related regret refers to a person's unfulfilled aspirations that should have been achieved but were not. Future-related regret refers to the anticipation that, as a result of premature death, one cannot achieve important goals in the future. Meaningfulness of death refers to one's concept of death and ability to make sense of it. These three antecedents are related to death salience in a complex way, mediated by coping mechanisms and their effects on one's beliefs about self and the world. The coping mechanisms include (but are not necessarily limited to) life review, life planning, identification with culture, and self-transcending processes. The model's developmental and practical applications are explored.  相似文献   
6.
Aim: To consider the question of whether to initiate trophic feeds with formula in the absence of own mother’s breastmilk or to wait for breastmilk to be available. Methods: A retrospective study of infants born prior to 32 weeks of gestation during the period 2012–2017 at a single tertiary center in Tel Aviv, Israel. Three TF groups were defined: exclusive breastmilk, mixed, and exclusive formula. Univariate and multivariate analyses were conducted. Logistic regression was used, and adjusted odds ratio and 95% interval were reported. Results: Univariate analysis demonstrated that infants in the exclusive breastmilk group were born earlier, had lower birth weights and lower Apgar scores, were given lower volumes of TF, and were more likely to have a longer hospital stay. Poor composite outcome was more common among the exclusive breastmilk group. Multivariate regression analysis revealed no differences in incidence of early neonatal morbidities between the groups, except for longer duration of parenteral nutrition in the exclusive breastmilk group. Conclusion: In our cohort, exclusive formula TF was not associated with increased risk of any of the studied morbidities. Clinicians should consider this finding in deciding between early TF or fasting while waiting for own mother’s breastmilk.  相似文献   
7.
The current monkeypox virus global spread and lack of data regarding clinical specimens’ infectivity call for examining virus infectivity, and whether this correlates with results from PCR, the available diagnostic tool. We show strong correlation between viral DNA amount in clinical specimens and virus infectivity toward BSC-1 cell line. Moreover, we define a PCR threshold value (Cq ≥ 35, ≤ 4,300 DNA copies/mL), corresponding to negative viral cultures, which may assist risk-assessment and decision-making regarding protective-measures and guidelines for patients with monkeypox.  相似文献   
8.
BackgroundThe vast majority of patients with cholangiocarcinoma (CC) have advanced disease at diagnosis and are candidates for palliative treatment only. The robustness of the randomized controlled trials regarding the treatment of CC are assessed.MethodsA systematic review of all randomized control trials (RCT) of treatments for both intra- and extrahepatic CC between 2010 and 2020 was performed. The survival-inferred fragility index (SIFI; the minimum number of reassignments of the best survivors between arms that would overturn the statistical outcomes) was calculated. In addition, the gain, or loss, in survival in RCTs was evaluated by the restricted mean survival time (RMST) difference. Finally, the level of spin i.e., misrepresentation of study outcomes, was measured in inconclusive studies to assess distorted reporting strategies.ResultsOut of 6,167 studies retrieved, 11 could be retained for full text revision (7 with both intra- and extrahepatic CC, 3 with peri-hilar CC, and 1 with peri-hilar or distal CC). Only 3 studies included resected patients (2 with both intra- and extrahepatic CC and 1 with peri-hilar or distal CC). Nine studies investigated systemic chemotherapy (including 3 after surgical resection), one study evaluated photodynamic therapy, and another investigated the use of an endoscopically inserted stent in the biliary tract. The median SIFI was −2 [interquartile range (IQR): −6.25, −0.25] across all studies. Overall, the median RMST difference was 0.56 months (IQR: 0.10, 0.95). Finally, for inconclusive studies, the level of spin was high, moderate, and low in respectively 12.5%, 25%, and 62.5% of the studies.ConclusionsRCTs of CC showed a low degree of robustness with a frequent proportion of associated spin.  相似文献   
9.
Tumors are theoretically capable of eliciting an antitumor immune response, but are often poorly immunogenic. Oncolytic viruses (OVs) have recently emerged as a promising strategy for the immunogenic delivery of tumor-associated antigens (TAAs) to cancer patients. However, safe and effective OV/TAA therapies have not yet been established. We have previously demonstrated that vectors based on Sindbis virus (SV) can inhibit tumor growth and activate the innate immune system in mice. Here, we demonstrate that SV vectors carrying a TAA generate a dramatically enhanced therapeutic effect in mice bearing subcutaneous, intraperitoneal, and lung cancers. Notably, SV/TAA efficacy was not dependent on tumor cell targeting, but was characterized by the transient expression of TAAs in lymph nodes draining the injection site. Early T-cell activation at this site was followed by a robust influx of NKG2D expressing antigen-specific cytotoxic CD8+ T cells into the tumor site, subsequently leading to the generation of long-lasting memory T cells which conferred protection against rechallenge with TAA-positive as well as TAA-negative tumor cells. By combining in vivo imaging, flow cytometry, cytotoxicity/cytokine assays, and tetramer analysis, we investigated the relationship between these events and propose a model for CD8+ T-cell activation during SV/TAA therapy.  相似文献   
10.
Amitai  Marianne M.  Klang  Eyal  Levartovsky  Asaf  Rozendorn  Noa  Soffer  Shelly  Taha  Gadeer Ali  Ungar  Bella  Greener  Tomer  Ben-Horin  Shomron  Eliakim  Rami  Kopylov  Uri 《Abdominal imaging》2018,43(12):3207-3212
Background and aims

Distinguishing between fibrotic and inflammatory strictures in Crohn’s disease (CD) is still challenging. The capacity of diffusion-weighted (DWI) magnetic resonance (MRE) to identify intestinal fibrosis was recently demonstrated; however, the therapeutic implications of this association have never been evaluated. The aim of the current study was to identify imaging features, including DWI, which can predict response to anti-inflammatory treatment in patients with stricturing CD.

Methods

Consecutive CD patients with intestinal strictures that initiated treatment with anti-tumor necrosis alpha (anti-TNF) between June 2012 and April 2017 with MRE adjacent to treatment onset were retrospectively collected. The primary outcome was treatment failure, defined as drug discontinuation, CD-related surgery, or endoscopic dilatation of the stricture. Clinical, demographic, and imaging data were compared between patients who did and did not develop treatment failure within 12 months of anti-TNF treatment initiation.

Results

A total of 21 patients were included in the study; 9/21 (42.8%) developed treatment failure. None of the clinical/demographic parameters were associated with the risk of treatment failure. Among imaging parameters, only ADC value (< 1 × 10−3 mm2/s) was significantly associated with the risk of treatment failure (AUC = 0.81, 66% vs. 0%, p = 0.015).

Conclusions

Our results suggest that ADC value on DWI MRE may predict the risk of treatment failure in stricturing CD. If replicated in larger studies, these results may guide therapeutic decisions and suggest avoiding anti-TNF treatment.

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