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51.

Background

Children with a solitary kidney (SK) have an increased long-term risk of hypertension, albuminuria and glomerulosclerosis. In this study, we assessed the early signs of impaired glomerular filtration in children with a SK from birth or from early infancy.

Methods

Renal growth and function at ages 4–15.5 years were studied in 38 children with SK and 40 matched control subjects in terms of accelerated growth.

Results

The systolic/diastolic blood pressure Z-scores (p?=?0.01/<0.05) and the resistance index (RI) of the arcuate arteries (p?=?0.05) were higher in the children with SK. Creatinine clearance and 24-h protein and albumin urinary excretion showed no difference. All but seven children with SK had 99mTc diethylene-triamine pentaacetic acid glomerular filtration rate values of >80 ml/min/1.73 m2. An independent positive correlation was found between length of the follow-up time and 24-h albumin urinary excretion (β?=?0.54, p?<?0.01). Accelerated postnatal growth was positively related with kidney volume (β?=?0.35, p?<?0.05).

Conclusions

Among our patient cohort, renal function was well preserved at ages 4–15.5 years in children who were born with a SK. However, both their higher blood pressure and RI and the correlation of 24-h albumin urinary excretion with length of follow-up time underline the need for monitoring to detect early signs of glomerular hyperfiltration and, if necessary, implement timely intervention. SK hypertrophy was found to be correlated with postnatal growth.  相似文献   
52.
IL-17-producing gamma delta (γδT17) cells are innate lymphocytes critical for antibacterial protection at barrier surfaces such as the skin but also highly pathogenic during inflammation. It is therefore important to understand the cellular and molecular mechanisms that could counter-balance overt γδT17 cell activation. Immune checkpoint receptors (ICRs) deliver inhibitory signals to activated lymphocytes and have been implicated as negative regulators of mouse γδT17 cells. In this report, we investigated the cytokine signals that induce ICR expression on γδT17 cells and studied the in vivo role of the Src-homology-2 phosphatases 1 and 2 (SHP-1 and SHP-2) in the context of γδT17-induced psoriasis. We found that surface expression of ICRs can be induced by cytokines; however, SHP-1 or SHP-2 could not inhibit γδT17 responses. In this regard, conditional deletion of SHP-1, SHP-2, or both did no impact γδT17 cell development, expansion, cytokine production, or skin pathology.  相似文献   
53.
Initiation of adaptive immunity to particulate antigens in lymph nodes largely depends on their presentation by migratory dendritic cells (DCs). DC subsets differ in their capacity to induce specific types of immunity, allowing subset-specific DC-targeting to influence vaccination and therapy outcomes. Faithful drug design, however, requires exact understanding of subset-specific versus global activation mechanisms. cDC1, the subset of DCs that excel in supporting immunity toward viruses, intracellular bacteria, and tumors, express uniquely high levels of the pattern recognition receptor TLR3. Using various murine genetic models, we show here that both, the cDC1 and cDC2 subsets of cDCs are activated and migrate equally well in response to TLR3 stimulation in a cell extrinsic and TNF-α dependent manner, but that cDC1 show a unique requirement for type I interferon signaling. Our findings reveal common and differing pathways regulating DC subset migration, offering important insights for the design of DC-based vaccination and therapy approaches.  相似文献   
54.
Chronic obstructive pulmonary disease (COPD) is characterized by expiratory airflow limitation, but current diagnostic criteria only consider flow till the first second and are therefore strongly debated. We aimed to develop a data-based individualized model for flow decline and to explore the relationship between model parameters and COPD presence. A second-order transfer function model was chosen and the model parameters (namely the two poles and the steady state gain (SSG)) from 474 individuals were correlated with COPD presence. The capability of the model to predict disease presence was explored using 5 machine learning classifiers and tenfold cross-validation. Median (95 % CI) poles in subjects without disease were 0.9868 (0.9858–0.9878) and 0.9333 (0.9256–0.9395), compared with 0.9929 (0.9925–0.9933) and 0.9082 (0.9004–0.9140) in subjects with COPD (p < 0.001 for both poles). A significant difference was also found when analysing the SSG, being lower in COPD group 3.8 (3.5–4.2) compared with 8.2 (7.8–8.7) in subjects without (p < 0.0001). A combination of all three parameters in a support vector machines corresponded with highest sensitivity of 85 %, specificity of 98.1 % and accuracy of 88.2 % to COPD diagnosis. The forced expiration of COPD can be modelled by a second-order system which parameters identify most COPD cases. Our approach offers an additional tool in case FEV1/FVC ratio-based diagnosis is doubted.  相似文献   
55.
Langerhans cell histiocytosis is a rare neoplastic proliferative disorder of the Langerhans cells. The clinical course is variable, ranging from a low symptomatic single bone lesion to fatal multiple organ involvement. Rarely, the sternum can be the first and single location of the disease. We report on a 12‐year‐old boy who presented with an aggressive lytic lesion of the proximal sternum associated with local pain and afternoon fever. Histopathological analysis of the closed biopsy specimen indicated eosinophilic granuloma of bone/Langerhans cell histiocytosis. Soon after the biopsy procedure the pain and fever subsided. Computed tomography at 2 months showed healing of the lytic lesion. The patient received no other type of treatment. At 2 year follow up he was symptom and disease free.  相似文献   
56.
Background and Objective  Prostate cancer (PCa) is a severe public health issue and the most common cancer worldwide in men. Early diagnosis can lead to early treatment and long-term survival. The addition of the multiparametric magnetic resonance imaging in combination with ultrasound (mpMRI-U/S fusion) biopsy to the existing diagnostic tools improved prostate cancer detection. Use of both tools gradually increases in every day urological practice. Furthermore, advances in the area of information technology and artificial intelligence have led to the development of software platforms able to support clinical diagnosis and decision-making using patient data from personalized medicine. Methods  We investigated the current aspects of implementation, architecture, and design of a health care information system able to handle and store a large number of clinical examination data along with medical images, and produce a risk calculator in a seamless and secure manner complying with data security/accuracy and personal data protection directives and standards simultaneously. Furthermore, we took into account interoperability support and connectivity to legacy and other information management systems. The platform was implemented using open source, modern frameworks, and development tools. Results  The application showed that software platforms supporting patient follow-up monitoring can be effective, productive, and of extreme value, while at the same time, aiding toward the betterment medicine clinical workflows. Furthermore, it removes access barriers and restrictions to specialized care, especially for rural areas, providing the exchange of medical images and patient data, among hospitals and physicians. Conclusion  This platform handles data to estimate the risk of prostate cancer detection using current state-of-the-art in eHealth systems and services while fusing emerging multidisciplinary and intersectoral approaches. This work offers the research community an open architecture framework that encourages the broader adoption of more robust and comprehensive systems in standard clinical practice.  相似文献   
57.
BackgroundForce‐time integral (FTI) is an ablation marker of lesion quality and transmurality. A target FTI of 400 gram‐seconds (gs) has been shown to improve durability of pulmonary vein isolation, following atrial fibrillation ablation. However, relevant targets for cavotricuspid isthmus (CTI) ablation are lacking.HypothesisWe sought to investigate whether CTI ablation with 600 gs FTI lesions is associated with reduced rate of transisthmus conduction recovery compared to 400 gs lesions.MethodsFifty patients with CTI‐dependent flutter were randomized to ablation using 400 gs (FTI400 group, n = 26) or 600 gs FTI lesions (FTI600 group, n = 24). The study endpoint was spontaneous or adenosine‐mediated recovery of transisthmus conduction, after a 20‐min waiting period.ResultsThe study endpoint occurred in five patients (19.2%) in group FTI400 and in four patients (16.7%) in group FTI600, p = .81. First‐pass CTI block was similar in both groups (50% in FTI400 vs. 54.2% in FTI600, p = .77). There were no differences in the total number of lesions, total ablation time, procedure time and fluoroscopy duration between the two groups. There were no major complications in any group. In the total population, patients not achieving first‐pass CTI block had significantly higher rate of acute CTI conduction recovery, compared to those with first‐pass block (29.2% vs. 7.7% respectively, p = .048).ConclusionsCTI ablation using 600 gs FTI lesions is not associated with reduced spontaneous or adenosine‐mediated recurrence of transisthmus conduction, compared to 400 gs lesions.  相似文献   
58.
59.
BACKGROUND: Telomerase preserves telomeres' function and structure preventing cellular senescence. Its activity is reduced in peripheral blood mononuclear cells (PBMC) of haemodialysis (HD) patients. The purpose of this study is to investigate the potential correlation between increased oxidative stress/inflammation and telomerase activity in PBMC of HD patients. METHODS: Telomerase activity was measured by PCR-ELISA in PBMC isolated from a group of 42 HD patients and 39 subjects with estimated glomerular filtration rate >or=80 mL/min (control group). Serum oxidized low-density lipoprotein (ox-LDL), tumour necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) were also measured in both groups by ELISA. RESULTS: Ox-LDL was negatively correlated to percentage telomerase activity in PBMC (r = -0.506, P = 0.000 in the whole group of 81 HD and normal subjects and r = -0.559, P < 0.001 in HD patients). TNF was also inversely associated with percentage telomerase activity in the whole group studied (r = -0.492, P = 0.000) while IL-10 was not. In stepwise multiple linear regression, taking into consideration the most important characteristics of the HD patients and control group, the only significant predictors for percentage telomerase activity in PBMC were ox-LDL and TNF (beta = -0.421, t = -4.083, P = 0.000 and beta = -0.381, t = -3.691, P = 0.000, respectively) while examining separately HD patients, the predictors for the same parameter were ox-LDL and HD duration (beta = -0.671, t = -4.709, P = 0.000 and beta = -0.349, t = -2.447, P = 0.023, respectively). CONCLUSION: Ox-LDL serum level is inversely correlated to telomerase activity in PBMC of HD patients. Our study proposes a new consequence of increased oxidative stress in HD patients: the premature cellular senescence potentially related to atherosclerosis through LDL oxidation.  相似文献   
60.
During the last two decades, there have been several reports of an increasing incidence of type 2 diabetes mellitus (T2DM) in children and adolescents, especially among those belonging to minority ethnic groups. This trend, which parallels the increases in prevalence and degree of pediatric obesity, has caused great concern, even though T2DM remains a relatively rare disease in children. Youth T2DM differs not only from type 1 diabetes in children, from which it is sometimes difficult to differentiate, but also from T2DM in adults, since it appears to be an aggressive disease with rapidly progressive β-cell decline, high treatment failure rate, and accelerated development of complications. Despite the recent research, many aspects of youth T2DM still remain unknown, regarding both its pathophysiology and risk factor contribution, and its optimal management and prevention. Current management approaches include lifestyle changes, such as improved diet and increased physical activity, together with pharmacological interventions, including metformin, insulin, and the recently approved glucagon-like peptide-1 analog liraglutide. What is more important for everyone to realize though, from patients, families and physicians to schools, health services and policy-makers alike, is that T2DM is a largely preventable disease that will be addressed effectively only if its major contributor (i.e., pediatric obesity) is confronted and prevented at every possible stage of life, from conception until adulthood. Therefore, relevant comprehensive, coordinated, and innovative strategies are urgently needed.  相似文献   
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