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31.
PURPOSE: We assessed the feasibility of a watchful waiting protocol with selective delayed intervention using clinical, prostate specific antigen (PSA) or histological progression as treatment indications for clinically localized prostate cancer. MATERIALS AND METHODS: In this prospective, single arm cohort study patients with favorable clinical parameters (stage T1b to T2b N0M0, Gleason score 7 or less and PSA 15 ng./ml. or less) are conservatively treated with watchful waiting. When a patient meets disease progression criteria, arbitrarily defined by the 3 parameters of the rate of PSA increase, clinical progression or histological upgrade on repeat prostate biopsy, appropriate treatment is implemented. Patients are followed every 3 months for the first 2 years and every 6 months thereafter. Serum PSA measurement and digital rectal examination are done at each visit and repeat prostate biopsy is performed 18 months after study enrollment. RESULTS: Since November 1995, the study has accrued 206 patients with a median followup of 29 months (range 2 to 66). Of these men 137 remain on the surveillance protocol with no disease progression, while 69 were withdrawn from study for various reasons. There was clinical, PSA and histological progression in 16, 15 and 5 cases, respectively. The estimated actuarial probability of remaining on the surveillance protocol was 67% at 2 years and 48% at 4. The probability of remaining progression-free was 81% and 67% at 2 and 4 years, respectively. CONCLUSIONS: A policy of watchful waiting with selectively delayed intervention based on predefined criteria of disease progression is feasible. This strategy offers the benefit of an individualized approach based on the demonstrated risk of clinical or biochemical progression with time and, thus, it may decrease the burden of therapy in patients with indolent disease, while providing definitive therapy for those with biologically active disease.  相似文献   
32.
Sir, Neutrophil gelatinase-associated lipocalin (NGAL), a memberof the lipocalin family, is readily excreted and detected inurine, due to its small molecular size (25 kDa) and resistanceto degradation. NGAL is highly accumulated in the human kidneycortical tubules, blood and urine, after nephrotoxic and ischaemicinjuries [1]. Thus, NGAL might represent an early, sensitive,non-invasive biomarker for acute renal injury [2], and urinaryNGAL might serve as an early marker for ischaemic renal injuryin children after cardiopulmonary bypass [3]. On the other hand,serum cystatin C was proposed as a new marker of glomerularfiltration rate (GFR), even in chronic kidney disease [4]. CystatinC has a low molecular weight (13 kDa) and is freely filtered  相似文献   
33.
The involvement of sodium/potassium-ATPase in regulating parathyroid hormone (PTH) secretion is inferred from in vitro studies. Recently, the α-klotho-dependent rapid recruitment of this ATPase to the parathyroid cell plasma membrane in response to low extracellular calcium ion was suggested to be linked to increased hormone secretion. In this study, we used an in vivo rat model to determine the importance of sodium/potassium-ATPase in PTH secretion. Glands were exposed and treated in situ with vehicle or ouabain, a specific inhibitor of sodium/potassium-ATPase. PTH secretion was significantly increased in response to ethylene glycol tetraacetic acid-induced acute hypocalcemia and to the same extent in both vehicle and ouabain groups. The glands were removed, and inhibition of the ATPase was measured by (86)rubidium uptake, which was found to be significantly decreased in ouabain-treated parathyroid glands, indicating inhibition of the ATPase. As ouabain induced systemic hyperkalemia, the effect of high potassium on hormone secretion was also examined but was found to have no effect. Thus, inhibition of the parathyroid gland sodium/potassium-ATPase activity in vivo had no effect on the secretory response to acute hypocalcemia. Hence, the suggested importance of this ATPase in the regulation of PTH secretion could not be confirmed in this in vivo model.  相似文献   
34.
Mixed chimerism has been suggested to induce tolerance to transplanted alloantigens. As the precise influence of mixed chimerism induction on the host organism has still not been fully elucidated, the aim of the present study was to explore this phenomenon in relation to the stem cell compartment.The experiment was performed on B6.SJL-PtprcaPep3b mice. Mixed chimerism induction protocols involved 3 Gy TBI (Day − 1 of the experiment), injection of 20-30 × 106 Balb C bone marrow cells (Day 0), and administration of blocking antibodies against CD40L (Day 0 and Day 4), anti-CD8 (Day − 2) with/without anti-NK1.1 (Day − 3). Selected groups of mice were also treated with cyclophosphamid (175 mg/kg) on Day 2. The presence of mixed chimerism was assessed in peripheral blood, bone marrow, and spleen, as well as in various subpopulations of leukocytes (CD4+, CD8+, CD45/B220+, Gr-1+, lin/Sca-1+/c-kit, lin/Sca-1+/c-kit+, lin/Sca-1/c-kit+). Furthermore, the percentage of stem/progenitor cells (lin/Sca-1+/c-kit, lin/Sca-1+/c-kit+, lin/Sca-1/c-kit+, VSEL, HSC) was analysed for the first time in bone marrow and peripheral blood of chimeric mice.The range of mixed chimerism differed significantly among various cell populations: it was lowest in CD8-positive cells and lin/Sca-1+/c-kit cells, and highest in granulocytes. The induction of mixed chimerism revealed a significant impact on the stem/progenitor cell frequency in recipient mice, providing potential therapeutic insights into the long-term immunologic tolerance observed in chimeric mice. Collectively, these findings contribute to further optimization of mixed chimerism induction protocols and might help in the introduction of this phenomenon into clinical practice.  相似文献   
35.
Background/Aims: Hypoxia-inducible factor (HIF)-1α is responsible for increased expression of genes engaged in angiogenesis. Our previous study indicated capillary rarefaction and atrophy of glycolytic fibers, mainly in locomotor muscles of uremic animals. Perhaps these changes are secondary to disturbances of HIF-1α in skeletal muscles. Methods: Expression of HIF-1α at mRNA and protein levels, as well as mRNA of vascular endothelial growth factor A (VEGF-A), vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2, endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS), in gastrocnemius muscle (MG) and longissimus thoracic muscle (ML) were measured by RT-PCR and Western blot. Rats were randomized to subtotal nephrectomy (CKD5/6), uninephrectomy (CKD1/2) or sham operation (controls). Results: For CKD5/6 versus controls, mRNA levels for HIF-1α, VEGF-A, VEGFR-1 and VEGFR-2 were significantly reduced only in MG, while eNOS was significantly decreased and iNOS was significantly increased only in ML. Western blot analysis indicated significantly increased HIF-1α protein levels in MG and ML from CKD1/2 animals versus controls, whereas in the CKD5/6 group, the level of HIF-1α protein decreased significantly in MG and increased significantly in ML versus controls and CKD1/2. Conclusion: The reduced expression of HIF-1α mRNA and protein in locomotor muscle from CKD5/6 animals may be involved in the pathogenesis of uremic myopathy. Increased expression of iNOS in the postural muscles may act as a protective factor through HIF-1α stabilization.  相似文献   
36.

Purpose

To assess factors influencing the long-term survival of elderly dialysis patients.

Methods

The study group consisted of 51 prevalent dialysis patients aged over 70?years (32 F and 19?M, all caucasians), who had been on a chronic hemodialysis (27) or peritoneal dialysis program (24) for at least 2?months; median age was 77?years, median time on dialysis before inclusion was 16?months, and median residual diuresis was 600?ml. The patients were prospectively followed up to 4?years, and an analysis of factors affecting survival was performed.

Results

Thirteen patients from the initial cohort of 51 (25.5?%) survived the whole 48-month observation period: 10 HD patients (37?%) and 3 PD patients (12.5?%). Annual mortality rate was 28.2?%: 37.4?% on PD vs. 20.9?% on HD. The dialysis modality had a significant impact on patients?? survival (p?=?0.049; Cox F-test). The independent mortality risk factors in the Cox proportional hazard regression model were higher plasma pro-atrial natriuretic peptide (pro-ANP) (p?=?0.006), lower residual diuresis (p?=?0.048), and lower systolic blood pressure (BP) value (p?=?0.039).

Conclusions

Paramount for the survival of the elderly on dialysis is adequate extracellular volume control. Residual renal function is a protective factor for the survival of elderly HD patients. This observation is novel, not previously reported in an elderly dialysis population.  相似文献   
37.
38.
In advanced uremia, parathyroid hormone (PTH) levels should be controlled at a moderately elevated level in order to promote normal bone turnover. As such, a certain degree of parathyroid hyperplasia has to be accepted. Uremia is associated with parathyroid growth. In experimental studies, proliferation of the parathyroid cells is induced by uremia and further promoted by hypocalcemia, phosphorus retention, and vitamin D deficiency. On the other hand, parathyroid cell proliferation might be arrested by treatment with a low-phosphate diet, vitamin D analogs, or calcimimetics. When established, parathyroid hyperplasia is poorly reversible. There exists no convincing evidence of programmed parathyroid cell death or apoptosis in hyperplastic parathyroid tissue or of involution of parathyroid hyperplasia. However, even considerable parathyroid hyperplasia can be controlled when the functional demand for increased PTH levels is removed by normalization of kidney function. Today, secondary hyperparathyroidism can be controlled in patients with long-term uremia in whom considerable parathyroid hyperplasia is to be expected. PTH levels can be suppressed in most uremic patients and this suppression can be maintained by continuous treatment with phosphate binders, vitamin D analogs, or calcimimetics. Thus modern therapy permits controlled development of parathyroid growth. When nonsuppressible secondary hyperparathyroidism is present, nodular hyperplasia with suppressed expression of the calcium-sensing receptor (CaR) and vitamin D receptor (VDR) has been found in most cases. An altered expression of some autocrine/paracrine factors has been demonstrated in the nodules. The altered quality of the parathyroid mass, and not only the increased parathyroid mass per se, might be responsible for uncontrollable hyperparathyroidism in uremia and after kidney transplantation.  相似文献   
39.

Background  

Even though there are several region-specific functional outcome questionnaires measuring neck disorders that have been developed in English-speaking countries, no Polish version has ever been validated. The purpose of our study was to translate, culturally adapt and validate the Neck Disability Index (NDI) and Copenhagen Neck Functional Disability Scale (CDS) for Polish-speaking patients with neck pain.  相似文献   
40.
The effect of low-level laser therapy (LLLT) on the cardiovascular system is not fully established. Since the endothelium is an important endocrine element, establishing the mechanisms of LLLT action is an important issue.The aim of the study was to evaluate the effect of transdermal LLLT on endothelial function.In this study, healthy volunteers (n?=?40, age?=?20–40 years) were enrolled. N?=?30 (14 female, 16 male, mean age 30?±?5 years) constituted the laser-irradiated group (LG). The remaining 10 subjects (6 women, 4 men, mean age 28?±?5 years) constituted the control group (CG). Participants were subjected to LLLT once a day for three consecutive days. Blood for biochemical assessments was drawn before the first irradiation and 24 h after the last session. In the LG, transdermal illumination of radial artery was conducted (a semiconductor laser λ?=?808 nm, irradiation 50 mW, energy density 1.6 W/cm2 and a dose 20 J/day, a total dose of 60 J). Biochemical parameters (reflecting angiogenesis: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), angiostatin; antioxidative status: glutathione (GSH) and the nitric oxide metabolic pathway: symmetric dimethylarginine (SDMA), asymmetric dimethylarginine (ADMA) and l-arginine) were assessed. In the LG, a significant increase in GSH levels and considerable decrease in angiostatin concentration following the LLLT were observed. No significant differences in levels of the VEGF, FGF, SDMA, ADMA were observed.LLLT modifies vascular endothelial function by increasing its antioxidant and angiogenic potential. We found no significant differences in levels of the nitric oxide pathway metabolites within 24 h following the LLLT irradiation.  相似文献   
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