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71.
A broad range of chronic conditions, including heart failure (HF), have been associated with vitamin D deficiency. Existing clinical trials involving vitamin D supplementation in chronic HF patients have been inconclusive. We sought to evaluate the outcomes of patients with vitamin D supplementation, compared with a matched cohort using real-world big data of HF hospitalization. This study was based on the Diagnosis Procedure Combination database in the Japanese Registry of All Cardiac and Vascular Datasets (JROAD-DPC). After exclusion criteria, we identified 93,692 patients who were first hospitalized with HF between April 2012 and March 2017 (mean age was 79 ± 12 years, and 52.2% were male). Propensity score (PS) was estimated with logistic regression model, with vitamin D supplementation as the dependent variable and clinically relevant covariates. On PS-matched analysis with 10,974 patients, patients with vitamin D supplementation had lower total in-hospital mortality (6.5 vs. 9.4%, odds ratio: 0.67, p < 0.001) and in-hospital mortality within 7 days and 30 days (0.9 vs. 2.5%, OR, 0.34, and 3.8 vs. 6.5%, OR: 0.56, both p < 0.001). In the sub-group analysis, mortalities in patients with age < 75, diabetes, dyslipidemia, atrial arrhythmia, cancer, renin-angiotensin system blocker, and β-blocker were not affected by vitamin D supplementation. Patients with vitamin D supplementation had a lower in-hospital mortality for HF than patients without vitamin D supplementation in the propensity matched cohort. The identification of specific clinical characteristics in patients benefitting from vitamin D may be useful for determining targets of future randomized control trials.  相似文献   
72.
Pig organ xenotransplantation offers a solution to the shortage of deceased human organs for transplantation. The pathobiological response to a pig xenograft is complex, involving antibody, complement, coagulation, inflammatory, and cellular responses. To overcome these barriers, genetic manipulation of the organ‐source pigs has largely been directed to two major aims—(a) deletion of expression of the known carbohydrate xenoantigens against which humans have natural (preformed) antibodies, and (b) transgenic expression of human protective proteins, for example, complement‐ and coagulation‐regulatory proteins. Conventional (FDA‐approved) immunosuppressive therapy is unsuccessful in preventing an adaptive immune response to pig cells, but blockade of the CD40:CD154 costimulation pathway is successful. Survival of genetically engineered pig kidneys in immunosuppressed nonhuman primates can now be measured in months. Non‐immunological aspects, for example, pig renal function, a hypovolemia syndrome, and rapid growth of the pig kidney after transplantation, are briefly discussed. We suggest that patients on the wait‐list for a deceased human kidney graft who are unlikely to receive one due to long waiting times are those for whom kidney xenotransplantation might first be considered. The potential risk of infection, public attitudes to xenotransplantation, and ethical, regulatory, and financial aspects are briefly addressed.  相似文献   
73.
74.
ObjectiveA high coronary artery calcification score (CACS) may be associated with high mortality in patients undergoing hemodialysis (HD). Recently, effects of iron on vascular smooth muscle cell calcification have been described. We aimed to investigate the relationships between iron, CACS, and mortality in HD patients.MethodsWe studied 173 consecutive patients who were undergoing maintenance HD. Laboratory data and Agatston’s CACS were obtained at baseline for two groups of patients: those with CACS ≥400 (n = 109) and those with CACS <400 (n = 64). Logistic regression analyses for CACS ≥400 and Cox proportional hazard analyses for mortality were conducted.ResultsThe median (interquartile range) age and duration of dialysis of the participants were 67 (60–75) years and 73 (37–138) months, respectively. Serum iron (Fe) and transferrin saturation (TSAT) levels were significantly lower in participants with CACS ≥400 than in those with CACS <400, although the serum ferritin concentration did not differ between the groups. TSAT ≥21% was significantly associated with CACS ≥400 (odds ratio 0.46, p<0.05). TSAT ≥17%, Fe ≥63 µg/dL, and ferritin ≥200 ng/mL appear to protect against 5-year all-cause mortality in HD patients, independent of conventional risk factors of all-cause mortality (p < 0.05).ConclusionWe have identified associations between iron, CACS, and mortality in HD patients. Lower TSAT was found to be an independent predictor of CACS ≥400, and iron deficiency (low TSAT, iron, or ferritin) was a significant predictor of 5-year all-cause mortality in HD patients.  相似文献   
75.
The proliferating cell nuclear antigen (PCNA) is a nuclear protein that leads DNA synthesis by the DNA polymerase delta. As the PCNA gene is strongly expressed in invasive gastric cancer cells with high proliferative activity, PCNA is suspected of playing an important role in the proliferation and advancement of gastric cancer. Thus, the effects of antisense oligonucleotides specific for PCNA mRNA were examined in seven gastric cancer cell lines. It was found that treatment with antisense oligonucleotides at concentrations of 10–40 M dose-dependently inhibited the growth of all cell lines; however, random sequence oligonucleotides did not modify the proliferation of any type of cells. These results indicate that PCNA is essential for cell proliferation in gastric cancer cells, and that the growth inhibitory effect results from the inhibition of PCNA gene expression. Therefore, PCNA-specific antisense oligonucleotides may be effective in the treatment of gastric cancer.  相似文献   
76.
Invading and resident macrophages were studied in the regenerating rat vagus nerve in vivo and in vitro, using antibodies to invading (EDI) and resident (ED2) macrophages. Fresh vagus nerves contained no EDI positive macrophages as revealed by immunocytochemical staining. In crush lesioned nerves in vivo, the number of EDI positive cells around and distal to the crush lesion, increased dramatically with time. Interestingly, EDI positive cells, although few, appeared in the cultured vagus nerves subjected to a crush lesion. Resident ED2 positive macrophages were abundant in fresh nerves. In vivo, there was a small increase of ED2 positive macrophages at the crush area as regeneration proceeded. In contrast, no increase was observed in vitro and after 3 days no ED2 stained macrophages were found. Immunocytochemical staining for low-affinity NGF-receptors showed a dramatic increase at the crush and distal to it in vivo, while in vitro, the receptors were upregulated along the entire nerve. The results suggest that invading macrophages may not be crucial for the initial and early outgrowth of sensory nerve fibres in peripheral nerves.  相似文献   
77.
Two children with intractable fecal incontinence after correction of high anorectal malformations were successfully managed by the daily administration of a glycerin enema into the cecum via an appendicocecostomy or tubularized cecostomy, according to the method of Malone's antegrade continence enema (ACE). Fluoroscopic defecography performed during this procedure in each patient disclosed that the glycerin enema promptly evoked cecal peristalsis, which was transmitted to the distal colon and rectum, and squeezed out almost all the fecal matter, evacuating it from the anus. However, two enemas within a short interval were required to achieve a complete washout of feces. Although this report describes only two patients, our experience confirmed that the ACE was very effective and that adding the word continence to antegrade enema was justifiable. Moreover, fluoroscopic defecography was proven to play a significant role in determining the appropriate regimens of this technique to achieve complete washout of the feces.  相似文献   
78.
Summary Substance P injected into the lumbar subarachnoid space of rats depressed the tail-flick response to radiant heat in a dose-dependent way. The effective doses ranged from 0.1 g to 100 g per rat (ED 50: 1.5 g/rat). The maximum of the effect was reached 20 min after intrathecal injection and the effect lasted for about 30 min. An antinociceptive effect was also observed after intrathecal injection of substance P 1 g to spinal rats. The depression of the tail-flick response produced by intrathecal administration of substance P was abolished by intrathecal (5 g/rat) or i.p. (0.5 mg/kg) injections of naloxone.Supported by the Sonderforschungsbereich 38 Membranforschung  相似文献   
79.
The BALB/3T3 mouse embryo cell line, noted for its marked postconfluence inhibition of proliferation, anchorage dependence, and high serum requirement, and frequently studied as a prototype nontumorigenic "fibroblast" line that is compared with tumorigenic sublines transformed with various agents, produced tumors within 2 to 3 months when an average of 3 X 10(4) cells were implanted s.c. attached to 1- X 5- X 10-mm polycarbonate platelets. Plastic platelets alone produced no tumors after 1 year of observation. The tumors, as well as others arising from implants of BALB/3T3 cells attached to 3-mm glass beads, were given the histological diagnosis of "vasoformative saroma" because the tumor cells frequently formed vascular channels. The vasoformative pattern and the results of specific staining for reticulin and collagen support the likelihood that BALB/3T3 cells originated from endothelial cells rather than from fibroblasts. That the tumors were derived from BALB/3T3 cells and not host cells was proved when tumors arising in BALB/c X C57BL/6 F1 hybrids were shown to be transplantable to BALB/c but not to C57BL/6 mice. The cultured tumor cells showed loss of both postconfluence inhibition of proliferation and anchorage dependence. Evidence of the induction of endogenous oncornaviruses was obtained in only one of four tumors tested. These tumors also exhibited tumor-unique transplantation rejection antigens. We conclude that BALB/3T3 cells are preneoplastic and give rise to different spontaneously transformed clones bearing unique tumor rejection antigens when implanted in vivo attached to a solid substrate.  相似文献   
80.
The ability of endogenous neurotrophins, including nerve growth factor (NGF), to promote the survival and development of neurons provides convincing evidence for their therapeutic potential, despite significant barriers to their successful clinical use. Many of these barriers might be surmountable, however, by strategies that enhance endogenous neurotrophin signaling. We evaluated a series of substituted pyrimidines for their ability to enhance the effects of NGF. KP544 [2‐amino‐5‐(4‐chlorophenylethynyl)‐4‐(4‐trans‐hydroxycyclohexylamino) pyrimidine] amplified NGF‐induced neurite outgrowth of PC12 cells approximately 2‐fold at 2 µM. KP544 also enhanced choline acetyltransferase activity, a marker of differentiation induced by either NGF or by cyclic AMP, by 3‐ to 8‐fold, with a 2‐fold amplification at 0.12–0.3 µM. This amplification occurred at all concentrations of NGF used including those that maximally stimulated the cells. KP544 did not increase the levels of phosphorylated mitogen‐activated protein kinases (MAPK) above that seen with NGF alone. These studies suggested that KP544 functions within the cell at a site that is downstream from or independent of MAPK signaling. NGF‐induced neurite outgrowth in a human cell line (SH‐SY5Y neuroblastoma cells) was also enhanced with KP544 treatment. Primary embryonic rat cortical cultures were used to extend the observations beyond the studies with the immortalized cell lines. In addition to effects on neurite outgrowth, KP544 protected these cells from glutamate‐induced death. Overall, the data suggest that KP544 can selectively interact in the differentiation pathway downstream of MAPK in a manner that amplifies nerve growth factor and cyclic AMP effects and is also neuroprotective. Drug Dev. Res. 62:49–59, 2004. © 2004 Wiley‐Liss, Inc.  相似文献   
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