Myopia onset and progression: can it be prevented?

Myopia is the commonest ocular abnormality and the high and growing prevalence of myopia, especially but not only in Asian populations, as well as its progressive nature in children, has contributed to a recent surge in interest. Such worldwide growing prevalence seems to be associated with increasing educational pressures, combined with life-style changes, which have reduced the time that children spend outdoors. Highly nearsighted people are at greater risk for several vision-threatening problems such as retinal detachments, choroidal neovascularization, cataracts and glaucoma, thus the potential benefits of interventions that can limit or prevent myopia progression would be of remarkable social impact. Our understanding of the regulatory processes that lead an eye to refractive errors is undoubtedly incomplete but has grown enormously in the last decades thanks to the animal studies, observational clinical studies, and randomized clinical trials recently published. In this review we assess the effects of several types of life-style and interventions, including outdoor activities, eye drops, undercorrection of myopia, multifocal spectacles, contact lenses, and refractive surgery on the onset and progression of nearsightedness.     

The long-term effectiveness of generic adult fixed-dose combination antiretroviral therapy for HIV-infected Ugandan children

Background

Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.

Objective

To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.

Methods

Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.

Results

From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.

Conclusion

Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success.     

The glucocorticoid in acute decompensated heart failure: Dr Jekyll or Mr Hyde?

Glucocorticoid administration is not recommended in patients with heart failure because of its related sodium and fluid retention. However, previous experimental and clinical studies have demonstrated that glucocorticoids can also induce a diuretic effect and improve renal function in patients with acute decompensated heart failure (ADHF) with refractory diuretic resistance. We report the case of a 65-year-old man with a known diagnosis of aortic stenosis, systolic ventricular dysfunction, and chronic obstructive pulmonary disease who was admitted for ADHF. After 3 days, during which resistance to conventional therapy was observed, intravenous methylprednisolone (60 mg/d) was added to ongoing medical treatment. Three days after the onset of glucocorticoid therapy, daily urine volume progressively increased (up to 5.8 L/d). Concurrently, signs and symptoms of congestion improved, the weight and brain natriuretic peptide plasma levels decreased (?7 kg and ?46%, respectively) and glomerular filtration rate increased (+26%). Bioimpedance vector analysis showed a net reduction of fluid content (from 88.4% to 73.6% of hydration at discharge). In conclusion, this case report suggests that in a patient with ADHF and congestion resistant to diuretic therapy, glucocorticoid administration is safe and associated with improvement in congestion, neurohormonal status, and renal function. These data support the possible usefulness of glucocorticoids in this setting.     

The effect of adrenoceptor agonists and antagonists on histamine-induced wheal response in the skin of normal subjects and atopic patients

The role of the adrenergic mechanism in the pathogenesis of atopic diseases is controversial. Recent experimental and clinical reports have suggested that beta-2 adrenergic stimulation impairs and beta-2 adrenergic blockade enhances the histamine effect on vascular permeability. This led us to study the effect of salbutamol and of propranolol on histamine-induced cutaneous response in 13 healthy subjects and in 16 patients with allergic oculo-rhinitis. Both in normal subjects and in atopic patients salbutamol attenuated the whealing response to histamine and the protective effect of salbutamol was counteracted by propranolol. The ability, however, of salbutamol to inhibit histamine-induced response was significantly reduced in 50% of atopic patients. These findings suggest that beta-2 adrenergic hyporesponsiveness is present in some allergic patients.     

Regulation of mRNA and protein levels of beta1 integrin variants in human prostate carcinoma

Alterations of integrin expression levels in cancer cells correlate with changes in invasiveness, tumor progression, and metastatic potential. The beta1C integrin, an alternatively spliced form of the human beta1 integrin, has been shown to inhibit prostate cell proliferation. Furthermore, beta1C protein levels were found to be abundant in normal prostate glandular epithelium and down-regulated in prostatic adenocarcinoma. To gain further insights into the molecular mechanisms underlying abnormal cancer cell proliferation, we have studied beta1C and beta1 integrin expression at both mRNA and protein levels by Northern and immunoblotting analysis using freshly isolated neoplastic and normal human prostate tissue specimens. Steady-state mRNA levels were evaluated in 38 specimens: 33 prostatic adenocarcinomas exhibiting different Gleason's grade and five normal tissue specimens that did not show any histological manifestation of benign prostatic hypertrophy. Our results demonstrate that beta1C mRNA is expressed in normal prostate and is significantly down-regulated in neoplastic prostate specimens. In addition, using a probe that hybridizes with all beta1 variants, mRNA levels of beta1 are found reduced in neoplastic versus normal prostate tissues. We demonstrate that beta1C mRNA down-regulation does not correlate with either tumor grade or differentiation according to Gleason's grade and TNM system evaluation, and that beta1C mRNA levels are not affected by hormonal therapy. In parallel, beta1C protein levels were analyzed. As expected, beta1C is found to be expressed in normal prostate and dramatically reduced in neoplastic prostate tissues; in contrast, using an antibody to beta1 that recognizes all beta1 variants, the levels of beta1 are comparable in normal and neoplastic prostate, thus indicating a selective down-regulation of the beta1C protein in prostate carcinoma. These results demonstrate for the first time that beta1C and beta1 mRNA expression is down-regulated in prostate carcinoma, whereas only beta1C protein levels are reduced. Our data highlight a selective pressure to reduce the expression levels of beta1C, a very efficient inhibitor of cell proliferation, in prostate malignant transformation.     

NK and NKT-like cells in granulomatous and fibrotic lung diseases

Clinical and Experimental Medicine - Background The pathogenetic and regulatory roles of natural killer (NK) and natural killer T-like cells in interstitial lung diseases (ILDs), fibrotic and...