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51.

Objectives

To evaluate the occurrence of ventricular systolic dysfunction in human immunodeficiency virus (HIV)-related pulmonary arterial hypertension (PAH).

Background

Patients with HIV-related PAH may develop ventricular systolic dysfunction both as a consequence of PAH progression or of the myocardial involvement from the HIV infection itself.

Methods

Cardiac magnetic resonance imaging was applied to measure ejection fraction for the left ventricle and the right ventricle in patients with HIV-related PAH (n = 27) and in patients with PAH from other aetiologies (n = 115).

Results

In HIV-related PAH, ejection fraction values were lower and a higher proportion of patients presented with an advanced stage of ventricular dysfunction (55% vs. 25%; p = 0.009). In a multivariate model, PAH related to HIV infection remained independently associated with advanced ventricular dysfunction (p = 0.011).

Conclusions

Patients with HIV-related PAH have more prevalent and severe ventricular systolic dysfunction compared to patients with PAH from other aetiologies.  相似文献   
52.

Objective

The aim of this study was to assess the outcomes after radiofrequency inferior turbinate reduction (RITR) on objective and subjective nasal function in patients with nasal obstruction caused by turbinate hypertrophy and to evaluate the possible effect on olfactory function.

Study Design

Case series with planned data collection.

Setting

ENT division, university hospital.

Subjects and Methods

Forty consecutive patients who underwent RITR for allergic or nonallergic chronic rhinitis with inferior turbinate hypertrophy were tested before and two months after the surgical procedure, using the Sniffin' Sticks test battery, anterior rhinomanometry, and the nasal obstruction symptom evaluation (NOSE) scale.

Results

The total basal nasal resistance at 150 Pa diminished significantly two months after surgery. Preoperative olfactory tests showed anosmia in five percent (n = 2) of the patients, hyposmia in 82 percent (n = 33), and normosmia in 12 percent (n = 5). At two months from the intervention, two percent (n = 1) were diagnosed as anosmic, 12 percent (n = 5) as hyposmic, and 85 percent (n = 34) as normosmic. The means of preoperative odor threshold (T), discrimination (D), identification (I), and the overall TDI score improved significantly postoperatively (P < 0.001). The NOSE score in the two-month follow-up improved in 97.5 percent (n = 39) of patients, with a mean difference in pre- vs. postintervention score of 40.12 (95% confidence interval 35.75-44.25; P < 0.001).

Conclusion

RITR may provide excellent outcomes in terms of improvement in olfactory function and nasal flow in patients affected by turbinate hypertrophy refractory to medical therapy.  相似文献   
53.
Proteasome inhibition induces the accumulation of aggregated misfolded/ubiquitinated proteins in the aggresome; conversely, histone deacetylase 6 (HDAC6) inhibition blocks aggresome formation. Although this rationale has been the basis of proteasome inhibitor (PI) and HDAC6 inhibitor combination studies, the role of disruption of aggresome formation by HDAC6 inhibition has not yet been studied in multiple myeloma (MM). The present study aimed to evaluate the impact of carfilzomib (CFZ) in combination with a selective HDAC6 inhibitor (ricolinostat) in MM cells with respect to the aggresome‐proteolysis pathway. We observed that combination treatment of CFZ with ricolinostat triggered synergistic anti‐MM effects, even in bortezomib‐resistant cells. Immunofluorescent staining showed that CFZ increased the accumulation of ubiquitinated proteins and protein aggregates in the cytoplasm, as well as the engulfment of aggregated ubiquitinated proteins by autophagosomes, which was blocked by ricolinostat. Electron microscopy imaging showed increased autophagy triggered by CFZ, which was inhibited by the addition of ACY‐1215. Finally, an in vivo mouse xenograft study confirmed a decrease in tumour volume, associated with apoptosis, following treatment with CFZ in combination with ricolinostat. Our results suggest that ricolinostat inhibits aggresome formation, caused by CFZ‐induced inhibition of the proteasome pathway, resulting in enhanced apoptosis in MM cells.  相似文献   
54.
OBJECTIVE: The aims of the study were to assess the effect of intra-articular treatment with triamcinolone hexacetonide (TH) in juvenile idiopathic arthritis (JIA) and to investigate whether treatment response correlates with the presence of antinuclear antibodies (ANA) in the serum and/or B CD5+ and T gamma/delta + lymphocytes in the synovial fluid. METHODS: A total of 37 patients (81% females, 56% ANA+) with oligoarticular JIA involving knees were treated with intra-articular injections of TH after failing to respond to NSAIDs for two months. Eighteen patients were treated within 6 months of onset, 19 were treated more than 6 months after onset. RESULT: Mean duration of remission was 13.9 months. Twelve patients (7 ANA+) had stable remission after a single injection; 13 patients (3 ANA+) experienced more than 6 months' remission but subsequently had a relapse; 12 patients (11 ANA+) had a relapse within six months of injection. Of 20 patients treated within 6 months of onset, 17 had stable remission whereas only 8 out of 17 who were treated during relapse attained stable remission (p = 0.03). The mean percentage of T gamma/delta + and of B CD5+ lymphocytes in synovial fluid was the same as in peripheral blood of normal subjects. CONCLUSION: Our data indicate that local treatment with slow-release steroids is very effective in oligoarticular JIA. Prolonged remission was less likely in the presence of ANA positivity, probably because the disease is immunologically more active. Finally, our data suggest that the earlier the treatment, the easier it is to obtain a protracted, and possibly permanent, response.  相似文献   
55.
Lymphoid cells that express the nuclear hormone receptor RORγt are involved in containment of the large intestinal microbiota and defense against pathogens through the production of interleukin 17 (IL-17) and IL-22. They include adaptive IL-17-producing helper T cells (T(H)17 cells), as well as innate lymphoid cells (ILCs) such as lymphoid tissue-inducer (LTi) cells and IL-22-producing NKp46+ cells. Here we show that in contrast to T(H)17 cells, both types of RORγt+ ILCs constitutively produced most of the intestinal IL-22 and that the symbiotic microbiota repressed this function through epithelial expression of IL-25. This function was greater in the absence of adaptive immunity and was fully restored and required after epithelial damage, which demonstrates a central role for RORγt+ ILCs in intestinal homeostasis. Our data identify a finely tuned equilibrium among intestinal symbionts, adaptive immunity and RORγt+ ILCs.  相似文献   
56.
57.
58.
OBJECTIVES: The aim of the study was to analyze the behavior of oxidative stress and its interplay with CD40L, a protein that is implicated in atherosclerosis, in hypercholesterolemic children. BACKGROUND: Oxidative stress has been suggested to play a major role in premature atherosclerosis. METHODS: Forty-one children with hypercholesterolemia (mean age 9.28 +/- 0.5 years) and 40 children with normocholesterolemia (mean age 9.02 +/- 0.69 years) were matched for gender and age. Within each group, children were classified as having or not having a family history of cardiovascular disease. Serum levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative stress, and plasma levels of soluble CD40L (sCD40L) were measured in each child. In a subgroup of children with high (n = 8) or normal (n = 8) levels of serum cholesterol, platelet p38 mitogen-activated protein (MAP) kinase phosphorylation, a protein involved in the activation of nicotinamide adenine dinucleotide phosphate oxidase, was determined. RESULTS: Children with hypercholesterolemia had higher values of 8-OHdG and sCD40L compared with control subjects (0.55 +/- 0.06 ng/ml vs. 0.21 +/- 0.02 ng/ml, p < 0.001 and 0.55 +/- 0.04 ng/ml vs. 0.19 +/- 0.03 ng/ml, p < 0.001, respectively). A significant correlation between 8-OHdG and sCD40L was observed in children with high (r = 0.676, p < 0.001) or normal (r = 0.878, p < 0.001) levels of cholesterol. Children with a family history of cardiovascular disease tended to have higher values of 8-OHdG and sCD40L, but the difference was not significant. Analysis of platelet p38 MAP kinase showed that it was phosphorylated more in children with hypercholesterolemia compared with control subjects (36.8 +/- 5.8 AU vs. 8.0 +/- 4.5 AU, p < 0.001 respectively). CONCLUSIONS: Children with hypercholesterolemia have an early increase of oxidative stress that may be responsible for up-regulation of CD40L and potentially predispose to premature atherosclerosis.  相似文献   
59.
60.
In PC Cl3 cells, a continuous, fully differentiated rat thyroid cell line, P2Y(2) purinoceptor activation provoked a transient increase of [Ca(2+)](i), followed by a decreasing sustained phase. The alpha and beta1 protein kinase C (PKC) inhibitor G?6976 decreased the rate of decrement to the basal [Ca(2+)](i) level and increased the peak of Ca(2+) entry of the P2Y(2)-provoked Ca(2+)transients. These effects of G? 6976 were not caused by an increased permeability of the plasma membrane, since the Mn(2+) and Ba(2+) uptake were not changed by G? 6976. Similarly, the Na(+)/Ca(2+) exchanger was not implicated, since the rate of decrement to the basal [Ca(2+)](i) level was equally decreased in physiological and Na(+)-free buffers, in the presence of G? 6976. On the contrary, the activity of the sarcoplasmic-endoplasmic reticulum Ca(2+)ATPase (SERCA) 2b was profoundly affected by G? 6976 since the drug was able to completely inhibit the stimulation of the SERCA 2b activity elicited by P2-purinergic agonists. Finally, the PKC activator phorbol myristate acetate had effects opposite to G? 6976, in that it markedly increased the rate of decrement to the basal [Ca(2+)](i) level after P2Y(2) stimulation and also increased the activity of SERCA 2b. These results suggest that SERCA 2b plays a role in regulating the sustained phase of Ca(2+) transients caused by P2Y(2) stimulation.  相似文献   
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