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51.
Several clinical studies have demonstrated that retinopathy and ophthalmic complications are features that appear mostly as side effects in HCV patients undergoing interferon (IFN) therapy. Here we underline that HCV itself is also able to modulate genes involved in ocular pathologies. Presently an in vitro model of ocular tissue derived cells infected with HCV is missing. The establishment of such in vitro models would be helpful to better understand the mechanisms through which HCV induces optical pathologies in order to specifically target the causes of ocular disease.  相似文献   
52.
Nowadays, twin gestation is increased due to advances in assisted reproduction. Unquestionably, these pregnancies have an increased risk of foetal and maternal disorders. Single foetal death has a different incidence depending on gestational age; in the first trimester between 10-70%, in the second and third trimester it is a rare event, 0.5-7%.  相似文献   
53.

Aims

Circulating levels of microRNAs (miRNAs) are emergent promising biomarkers for cardiovascular disease. Altered expression of miRNAs has been related to heart failure (HF) and cardiac remodelling. We measured the concentration gradients across the coronary circulation to assess their usefulness to diagnose HF of different aetiologies.

Methods and results

Circulating miRNAs were measured in plasma samples simultaneously obtained from the aorta and the coronary venous sinus in patients with non‐ischaemic HF (NICM‐HF, n = 23) ischaemic HF (ICM‐HF, n = 41), and in control patients (n = 11). A differential modulation of circulating levels of miR‐423, ‐34a, ‐21‐3p, ‐126, ‐199 and ‐30a was found across the aetiology groups. Interestingly, a positive transcoronary gradient was found for miR‐423 (P < 0.001) and miR‐34a (P < 0.001) only in the ICM‐HF group. On the contrary, a positive gradient was found for miR‐21‐3p (P < 0.001) and miR‐30a (P = 0.030) only in the NICM‐HF group. Finally, no significant variations were observed in the transcoronary gradient of miR‐126 or miR‐199.

Conclusions

The present findings suggest that circulating levels of miRNAs are differentially expressed in patients with HF of different aetiologies. The presence of a transcoronary concentration gradient suggests a selective release of miRNAs by the failing heart into the coronary circulation. The presence of aetiology‐specific transcoronary concentration gradients in HF patients might provide important information to better understand their role in HF, and suggests they could be useful biomarkers to distinguish HF of different aetiologies.
  相似文献   
54.
55.
Serum levels of lipids, lipoproteins and apolipoproteins A-I and B were evaluated in 102 patients (75 males and 27 females; ages 58 +/- 8 and 61 +/- 7 years (mean +/- SD), respectively) with arteriosclerosis of the lower limbs of supra-aortic trunks. Compared to findings in 64 healthy, age-matched control subjects, male patients in both groups had significantly higher serum triglyceride levels (+42%, P less than 0.05), while female patients with lower limb arteriosclerosis showed significantly increased cholesterol and triglyceride concentrations (+19%, P less than 0.01 and +82%, P less than 0.05, respectively). LDL-triglycerides were also increased in all patients. HDL-cholesterol was significantly decreased in male patients with arteriosclerosis of the lower limbs (-27%, P less than 0.01) and the supra-aortic trunks (-28%, P less than 0.01), and in females of both groups (-26%, P less than 0.01 and -20%, P less than 0.01, respectively); in terms of percent, HDL2-cholesterol was reduced 2-fold compared to HDL3-cholesterol. Patient apolipoprotein A-I and B levels were unchanged. In male and female patients, correlations between triglycerides and HDL-cholesterol as well as HDL2-cholesterol were negative, but not significant; on the other hand, both correlations were negative and significant in male controls, while only the correlation between triglycerides and HDL2-cholesterol was negative and significant in the female controls. Since HDL-cholesterol, and in particular HDL2-cholesterol, concentrations seem closely related to the intravascular catabolism of triglyceride-rich lipoproteins, the absence of a significant correlation between these parameters in the patients suggests a possible alteration in this metabolic process.  相似文献   
56.
Einerhand  MP; Bakx  TA; Kukler  A; Valerio  D 《Blood》1993,81(1):254-263
An amphotropic retroviral vector, LgAL(delta Mo + PyF101) containing a human adenosine deaminase (ADA) cDNA was used to optimize procedures for the lasting genetic modification of the hematopoietic system of mice. The highest number of retrovirally infected cells in the hematopoietic tissues of long-term reconstituted mice was observed after transplantation of bone marrow (BM) cells that had been cocultured in the presence of both interleukin-1 alpha (IL-1 alpha) and IL-3. A significantly lower number was detected when IL-1 alpha was omitted from such cocultures. The yield of cells that generate spleen colony-forming cells (CFU-S) in the BM of lethally irradiated recipients (MRA-CFU-S) significantly improved on inclusion of the adherent cell fraction of cocultures in the transplant. Retroviral integration patterns in MRA-CFU-S-derived spleen colonies showed that an MRA-CFU-S can produce many CFU-S during BM regeneration. Expression of hADA was detected in the circulating white blood cells of long-term reconstituted animals, demonstrating that the LgAL(delta Mo + PyF101) vector is capable of directing the sustained expression of hADA, and in approximately 35% of the transduced MRA-CFU-S-derived spleen colonies. These results should facilitate the development of gene therapy protocols for the treatment of severe combined immunodeficiency caused by a lack of functional ADA.  相似文献   
57.

Purpose

To analyze the influence of adding gentamicin to a regimen consisting of β-lactam or vancomycin plus rifampicin on survival in patients suffering from Staphylococcal prosthetic valve endocarditis (SPVE).

Methods

From January 2008 to September 2016, 334 patients with definite SPVE were attended in the participating hospitals. Ninety-four patients (28.1%) received treatment based on β-lactam or vancomycin plus rifampicin and were included in the study. Variables were analyzed which related to patient survival during admission, including having received treatment with gentamicin.

Results

Seventy-seven (81.9%) were treated with cloxacillin (or vancomycin) plus rifampicin plus gentamicin, and 17 patients (18.1%) received the same regimen without gentamicin. The causative microorganism was Staphylococcus aureus in 40 cases (42.6%) and coagulase-negative staphylococci in 54 cases (57.4%). Overall, 40 patients (42.6%) died during hospital admission, 33 patients (42.9%) in the group receiving gentamicin and 7 patients in the group that did not (41.2%, P = 0.899). Worsening renal function was observed in 42 patients (54.5%) who received gentamicin and in 9 patients (52.9%) who did not (p = 0.904). Heart failure as a complication of endocarditis (OR: 4.58; CI 95%: 1.84–11.42) and not performing surgery when indicated (OR: 2.68; CI 95%: 1.03–6.94) increased mortality. Gentamicin administration remained unrelated to mortality (OR: 1.001; CI 95%: 0.29–3.38) in the multivariable analysis.

Conclusions

The addition of gentamicin to a regimen containing vancomycin or cloxacillin plus rifampicin in SPVE was not associated to better outcome.  相似文献   
58.
The long-term changes of liver stiffness (LS) in patients who achieve viral clearance after direct-acting anti-HCV therapy remain undefined. We conducted a multicentre prospective study to investigate this aspect. Patients with HCV infection treated with DAAs were enrolled from six Italian centres; they underwent clinical, biochemical, ultrasound and transient elastography evaluations before treatment (T0), 12 weeks (SVR12) and 24 months (T24) after the end of therapy. Among the 516 consecutive patients enrolled, 301 had cirrhosis. LS significantly decreased from T0 to SVR (14.3 vs 11.1 kPa, p = .002), with a progressive reduction until T24 (8.7 kPa, p < .001). However, only patients with steatosis and those who developed HCC did not experience a late improvement in LS. Multivariate analysis of baseline and follow-up variables identified steatosis as the only independent predictor of failure of LS improvement (OR 1.802, p = .013). ROC curve analysis of the association of LS with the risk of developing HCC showed that SVR12 ≥14.0 kPa had the highest accuracy (sensitivity 82%, specificity 99%; AUC: 0.774). Multivariate analysis revealed that LS was the only variable independently associated with an increased risk of developing HCC (OR 6.470, p = .035). Achieving an SVR was associated with a progressive, long-term decline of LS, suggesting a late improvement in liver fibrosis, besides the resolution of inflammation. Fatty liver and the development of HCC interfered with late reduction of LS. Patients with an LS ≥14 kPa at 12 weeks after the end of treatment were at higher risk for developing HCC.  相似文献   
59.
Long term survival after pancreatic resection for pancreatic adenocarcinoma   总被引:7,自引:0,他引:7  
OBJECTIVE: The aim of this study was to determine the long term survival of patients with pancreatic adenocarcinoma who underwent surgical resection and to assess the association of clinical, pathological, and treatment features with survival. METHODS: Between January, 1990, and December, 1998, 125 patients underwent a pancreaticoduodenal or partial pancreatic resection for pancreatic ductal adenocarcinoma at our institution. The records of these patients were reviewed for demographics, tumor characteristics including size, histological grade, margin status, lymph node status, surgical TNM staging, and postoperative adjuvant therapy. The primary outcome variable analyzed was survival. RESULTS: A total of 116 patients had complete follow-up and were included in the final analysis. The median survival after surgery was 16 months. The 1-, 3-, 5-, and 7-yr survival rates for all 116 patients were 60%, 23%, 19%, and 11%, respectively. The 1-, 3-, 5-, and 7-yr survival rates for patients who received adjuvant therapy were 69%, 28%, 23%, and 18% compared with 20% and 0% in patients who did not receive adjuvant therapy (p < 0.0001). The 1-, 3-, 5-, and 7-yr survival rates for patients with negative lymph nodes were 73%, 38%, 26%, and 22% compared with survival rates of 52%, 14%, 14%, and 9% in patients with positive lymph nodes (p = 0.01). In multivariate analyses, adjuvant therapy was the only feature found to be strongly associated with survival (hazards ratio = 0.26, 95% CI = 0.15-0.44). CONCLUSIONS: The overall 5- and 7-yr survival rates of 19% and 11% in our study further validate that surgical resection in patients with pancreatic adenocarcinoma can result in long term survival, particularly when performed in association with adjuvant chemoradiation.  相似文献   
60.
Background Patients with mild heart failure show a reduction in preload reserve mechanism during volume expansion. At this time, the effects of volume expansion on left ventricular (LV) diastolic filling in this subset of patients have not been well characterized. Methods We evaluated the effects of acute volume loading on Doppler parameters of LV filling in 10 healthy control subjects and in 12 patients with idiopathic dilated cardiomyopathy (DCM). In patients with DCM, the effects of losartan on diastolic adaptation to volume load were also investigated. Results During volume loading, the healthy control subjects showed a decrease in isovolumic relaxation time (F = 5.3, P < .05) but an increase in the LV peak filling rate (F = 52.9, P < .001) and velocity time integral of both systolic (F = 72.8, P < .001) and diastolic (F = 4.6, P < .05) pulmonary venous flow. In patients with DCM, isovolumic relaxation time decreased more than in control subjects (F = 8.1, P < .01), and the deceleration time of the early mitral wave was reduced (F = 26.3, P < .001). Furthermore, the duration of pulmonary venous flow reversal exceeded that of mitral flow at atrial contraction (F = 28.5, P < .001). After treatment with losartan, the deceleration time of early mitral wave remained unchanged, and the duration of pulmonary venous flow reversal at atrial contraction did not exceed that of mitral flow; thus, a significant treatment effect was detectable (F = 5.6, P < .05; and F = 6.6, P <.05, respectively). Conclusions Control subjects respond to volume load with enhancement in early LV filling, whereas patients with DCM show an increase of LV filling pressure. Diastolic adaptation to volume load improves in patients with DCM after treatment with losartan. (Am Heart J 2002;143:433-40)  相似文献   
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