miR-29 is a major regulator of genes associated with pulmonary fibrosis

MicroRNAs (miRNA) are small regulatory RNAs that control gene expression by translational suppression and destabilization of target mRNAs. There is increasing evidence that miRNAs regulate genes associated with fibrosis in organs, such as the heart, kidney, liver, and the lung. In a large-scale screening for miRNAs potentially involved in bleomycin-induced fibrosis, we found expression of miR-29 family members significantly reduced in fibrotic lungs. Analysis of normal lungs showed the presence of miR-29 in subsets of interstitial cells of the alveolar wall, pleura, and at the entrance of the alveolar duct, known sites of pulmonary fibrosis. miR-29 levels inversely correlated with the expression levels of profibrotic target genes and the severity of the fibrosis. To study the impact of miR-29 down-regulation in the lung interstitium, we characterized gene expression profiles of human fetal lung fibroblast IMR-90 cells in which endogenous miR-29 was knocked down. This confirmed the derepression of reported miR-29 targets, including several collagens, but also revealed up-regulation of a large number of previously unrecognized extracellular matrix-associated and remodeling genes. Moreover, we found that miR-29 is suppressed by transforming growth factor (TGF)-β1 in these cells, and that many fibrosis-associated genes up-regulated by TGF-β1 are derepressed by miR-29 knockdown. Interestingly, a comparison of TGF-β1 and miR-29 targets revealed that miR-29 controls an additional subset of fibrosis-related genes, including laminins and integrins, independent of TGF-β1. Together, these strongly suggest a role of miR-29 in the pathogenesis of pulmonary fibrosis. miR-29 may be a potential new therapeutic target for this disease.

Potential mechanisms of anaphylaxis to COVID-19 mRNA vaccines

Anaphylaxis to vaccines is historically a rare event. The coronavirus disease 2019 pandemic drove the need for rapid vaccine production applying a novel antigen delivery system: messenger RNA vaccines packaged in lipid nanoparticles. Unexpectedly, public vaccine administration led to a small number of severe allergic reactions, with resultant substantial public concern, especially within atopic individuals. We reviewed the constituents of the messenger RNA lipid nanoparticle vaccine and considered several contributors to these reactions: (1) contact system activation by nucleic acid, (2) complement recognition of the vaccine-activating allergic effector cells, (3) preexisting antibody recognition of polyethylene glycol, a lipid nanoparticle surface hydrophilic polymer, and (4) direct mast cell activation, coupled with potential genetic or environmental predispositions to hypersensitivity. Unfortunately, measurement of anti-polyethylene glycol antibodies in vitro is not clinically available, and the predictive value of skin testing to polyethylene glycol components as a coronavirus disease 2019 messenger RNA vaccine-specific anaphylaxis marker is unknown. Even less is known regarding the applicability of vaccine use for testing (in vitro/vivo) to ascertain pathogenesis or predict reactivity risk. Expedient and thorough research-based evaluation of patients who have suffered anaphylactic vaccine reactions and prospective clinical trials in putative at-risk individuals are needed to address these concerns during a public health crisis.

Alveolar macrophage activation and an emphysema-like phenotype in adiponectin-deficient mice

Adiponectin is an adipocyte-derived collectin that acts on a wide range of tissues including liver, brain, heart, and vascular endothelium. To date, little is known about the actions of adiponectin in the lung. Herein, we demonstrate that adiponectin is present in lung lining fluid and that adiponectin deficiency leads to increases in proinflammatory mediators and an emphysema-like phenotype in the mouse lung. Alveolar macrophages from adiponectin-deficient mice spontaneously display increased production of tumor necrosis factor-alpha (TNF-alpha) and matrix metalloproteinase (MMP-12) activity. Consistent with these observations, we found that pretreatment of alveolar macrophages with adiponectin leads to TNF-alpha and MMP-12 suppression. Together, our findings show that adiponectin leads to macrophage suppression in the lung and suggest that adiponectin-deficient states may contribute to the pathogenesis of inflammatory lung conditions such as emphysema.

Rhinovirus-16 colds in healthy and in asthmatic subjects: similar changes in upper and lower airways

Rhinovirus (RV) infections appear to precipitate most asthma exacerbations. To investigate whether RV-16 induces different inflammatory changes in upper and lower airways of asthmatic and healthy subjects, we inoculated 10 nonatopic healthy and 11 atopic asthmatic adults with 2,000 TCID50 RV-16. Subjects recorded symptoms and peak flow daily; and they underwent spirometry, methacholine challenge (PC20), nasal lavage, and sputum induction at baseline and on Days 2, 4, 15, and 29 d after inoculation. One asthmatic subject developed an exacerbation requiring prednisone treatment 5 d after inoculation. The cold symptom severity (Jackson score) did not differ between groups. During the cold, asthma symptoms increased slightly from baseline in the asthmatic group; and PC20 decreased in the healthy group. However, peak flow, bronchodilator use, and spirometry did not change in either group. At baseline, asthmatics had higher neutrophils, eosinophils, and interleukin (IL)-6 in nasal lavage. After inoculation, both groups developed significant increases in nasal neutrophils, IL-6 and IL-8, and modest increases in sputum neutrophils and IL-6, but not IL-8. However, these changes did not differ between groups. IL-5, interferon-gamma, and RANTES were detected only in nasal lavages from two asthmatic subjects, who had the most severe colds. IL-11 was not detected in any sample. We conclude that inflammatory responses of upper and lower airways during RV-16 colds are similar in asthmatic and healthy subjects, and that RV-16 infection is not by itself sufficient to provoke clinical worsening of asthma.

Adiponectin attenuates lipopolysaccharide-induced acute lung injury through suppression of endothelial cell activation

Adiponectin (APN) is an adipose tissue-derived factor with anti-inflammatory and vascular protective properties whose levels paradoxically decrease with increasing body fat. In this study, APN's role in the early development of ALI to LPS was investigated. Intratracheal LPS elicited an exaggerated systemic inflammatory response in APN-deficient (APN(-/-)) mice compared with wild-type (wt) littermates. Increased lung injury and inflammation were observed in APN(-/-) mice as early as 4 h after delivery of LPS. Targeted gene expression profiling performed on immune and endothelial cells isolated from lung digests 4 h after LPS administration showed increased proinflammatory gene expression (e.g., IL-6) only in endothelial cells of APN(-/-) mice when compared with wt mice. Direct effects on lung endothelium were demonstrated by APN's ability to inhibit LPS-induced IL-6 production in primary human endothelial cells in culture. Furthermore, T-cadherin-deficient mice that have significantly reduced lung airspace APN but high serum APN levels had pulmonary inflammatory responses after intratracheal LPS that were similar to those of wt mice. These findings indicate the importance of serum APN in modulating LPS-induced ALI and suggest that conditions leading to hypoadiponectinemia (e.g., obesity) predispose to development of ALI through exaggerated inflammatory response in pulmonary vascular endothelium.

Sustained expression of alpha1-antitrypsin after transplantation of manipulated hematopoietic stem cells

Inherited mutations in the human alpha(1)-antitrypsin (AAT) gene lead to deficient circulating levels of AAT protein and a predisposition to developing emphysema. Gene therapy for individuals deficient in AAT is an attractive goal, because transfer of a normal AAT gene into any cell type able to secrete AAT should reverse deficient AAT levels and attenuate progression of lung disease. Here we present an approach for AAT gene transfer based on the transplantation of lentivirally transduced hematopoietic stem cells (HSCs). We develop a novel dual-promoter lentiviral system to transfer normal human AAT cDNA as well as a fluorescent tracking "reporter gene" into murine HSCs. After transplantation of 3,000 transduced HSCs into irradiated mouse recipients, we demonstrate simultaneous and sustained systemic expression of both genes in vivo for at least 31 weeks. The stem cells transduced with this protocol maintain multipotency, self-renewal potential, and the ability to reconstitute the hematopoietic systems of both primary and secondary recipients. This lentiviral-based system may be useful for investigations requiring the systemic secretion of anti-proteases or cytokines relevant to the pathogenesis of a variety of lung diseases.

Myasthenia gravis in South Africans: Racial differences in clinical manifestations

We present data on the phenotypic variation in myasthenia gravis of 205 subjects from a multi-racial South African cohort. Consecutive subjects seen more than twice from 1996 to 2006, were included. Documented observational data included a myasthenia gravis and extra-ocular eye muscle score. Results showed Black subjects were more likely than Whites to develop treatment-resistant complete ophthalmoplegia and ptosis (18% vs. 2%; p=0.041). Of the 14 patients with this phenotype, 13 had generalised disease and positive AChR antibodies. Despite similar sized cohorts, White subjects were more likely than Blacks to develop generalised myasthenia poorly responsive to therapy (p=0.005). There were no significant racial differences in the time between diagnosis to initiation of therapy, or the performance and timing of thymectomy. The racial variation in some phenotypic features of myasthenia gravis and outcome to therapy, highlights the need to study biological factors in different subgroups to develop a more rational approach to immuno-suppressive therapy.

Il-9 stimulates release of chemotactic factors from human bronchial epithelial cells

Interleukin (IL)-9 is a T helper 2 cytokine implicated as a candidate gene and contributor to human asthma. We hypothesized that the inflammatory potential of bronchial epithelium is affected by its local environment and explored this hypothesis with respect to the effect of IL-9 on bronchial epithelium. We investigated the response of primary and immortalized human bronchial epithelial cells to IL-9 stimulation with respect to the release of T-cell chemoattractant factors. In response to IL-9, the HBE4-E6/E7 cell line, but not BEAS-2B cells, released the T-cell chemoattractants IL-16 and regulated on activation, normal T cells expressed and secreted (RANTES) in a dose-dependent fashion. We found a similar dose response to IL-9 in primary cells from bronchial brushings of healthy subjects and that nearly all of the T-cell chemoattraction was attributable to IL-16 and RANTES. Reverse transcriptase/polymerase chain reaction of BEAS-2B, HBE4-E6/E7, and primary cells from two subjects revealed messenger RNA for IL-9 receptor (IL-9R) alpha but not in BEAS-2B cells. Fluorescence-activated cell sorter analysis of HBE4-E6/E7 and primary cells confirmed surface expression of the IL-9 receptor. Costimulation of both cell types with IL-9 and antibody to either gamma-common chain or IL-9Ralpha completely blocked the release of T-cell chemoattractant activity, confirming the primary role of a functioning IL-9 receptor for IL-9 signaling in HBE4-E6/E7 and primary bronchial epithelial cells. We conclude that IL-9 is a stimulus for airway epithelial cell release of T-cell chemoattractant factors, which in turn may modulate the immune response in allergic airway inflammation.

Efficacy of rectal artesunate compared with parenteral quinine in initial treatment of moderately severe malaria in African children and adults: a randomised study

BACKGROUND

Many patients with malaria of increasing severity cannot take medicines orally, and delay in injectable treatment can be fatal. We aimed to assess the reliability of absorption, antimalarial efficacy, and tolerability of a single rectal dose of artesunate in the initial management of moderately severe falciparum malaria.

METHODS

109 children and 35 adults were randomly assigned to rectal artesunate (single dose of about 10 mg/kg) or parenteral quinine treatment (10 mg/kg at 0, 4, and 12 h). The primary endpoint was the proportion of patients with peripheral asexual parasitaemia of less than 60% of that at baseline after 12 h. Secondary endpoints were clinical response and concentrations of drug in plasma. Analysis was by intention-to-treat.

FINDINGS

All artesunate-treated patients had pharmacodynamic or pharmacokinetic evidence of adequate drug absorption. 80 (92%) of 87 artesunate-treated children had a 12 h parasite density lower than 60% of baseline, compared with three of 22 (14%) receiving quinine (relative risk 0.09 [95% CI 0.04-0.19]; p<0.0001). In adults, parasitaemia at 12 h was lower than 60% of baseline in 26 (96%) of 27 receiving artesunate, compared with three (38%) of eight receiving quinine (relative risk 0.06 [0.01-0.44]; p=0.0009). These differences were greater at 24 h. Clinical response was equivalent with rectal artesunate and parenteral quinine.

INTERPRETATION

A single rectal dose of artesunate is associated with rapid reduction in parasite density in adults and children with moderately severe malaria, within the initial 24 h of treatment. This option is useful for initiation of treatment in patients unable to take oral medication, particularly where parenteral treatment is unavailable.

Pharmacokinetics of sulfadoxine and pyrimethamine in intermittent preventive treatment of malaria in pregnancy

Malaria during pregnancy is associated with maternal and fetal morbidity and mortality. In order to minimize the burden, sulfadoxine-pyrimethamine (SP) is widely used in Africa as an intermittent preventive treatment of malaria in pregnancy (IPTp). However, only limited data are available on the pharmacokinetics of sulfadoxine and pyrimethamine during pregnancy. We conducted a prospective, self-matched, multicenter study of 98 pregnant women in four African countries in order to determine the effects of pregnancy on SP pharmacokinetics. After adjusting for the effects of potential confounders, blood concentrations (associated with therapeutic efficacy) of pyrimethamine were higher (geometric mean ratio (GMR) 1.33; 95% confidence interval (CI) 1.18-1.51; P < 0.001) and those of sulfadoxine were lower (GMR 0.91; 95% CI 0.84-0.98; P = 0.013) on day 7 after SP administration during pregnancy than after the postpartum period. SP pharmacokinetic parameters differed significantly among the study sites. Given the inconsistency of changes in pharmacokinetic parameters between sulfadoxine and pyrimethamine as well as among the study sites, it is not possible to recommend any dose adjustment to prolong the therapeutic life span of the fixed dose combination of SP for IPTp on the basis of our study findings.

Development of cockroach immunotherapy by the Inner-City Asthma Consortium

BACKGROUND

Cockroach allergy is a key contributor to asthma morbidity in children living in urban environments.

OBJECTIVE

We sought to document immune responses to cockroach allergen and provide direction for the development of immunotherapy for cockroach allergy.

METHODS

Four pilot studies were conducted: (1) an open-label study to assess the safety of cockroach sublingual immunotherapy (SLIT) in adults and children; (2) a randomized, double-blind biomarker study of cockroach SLIT versus placebo in adults; (3) a randomized, double-blind biomarker study of 2 doses of cockroach SLIT versus placebo in children; and (4) an open-label safety and biomarker study of cockroach subcutaneous immunotherapy (SCIT) in adults.

RESULTS

The adult SLIT trial (n = 54; age, 18-54 years) found a significantly greater increase in cockroach-specific IgE levels between the active and placebo groups (geometric mean ratio, 1.92; P < .0001) and a trend toward increased cockroach-specific IgG4 levels in actively treated subjects (P = .09) but no evidence of functional blocking antibody response. The pediatric SLIT trial (n = 99; age, 5-17 years) found significant differences in IgE, IgG, and IgG4 responses between both active groups and the placebo group but no consistent differences between the high- and low-dose groups. In the SCIT study the treatment resulted in significant changes from baseline in cockroach IgE, IgG4, and blocking antibody levels. The safety profile of cockroach immunotherapy was reassuring in all studies.

CONCLUSIONS

The administration of cockroach allergen by means of SCIT is immunologically more active than SLIT, especially with regard to IgG4 levels and blocking antibody responses. No safety concerns were raised in any age group. These pilot studies suggest that immunotherapy with cockroach allergen is more likely to be effective with SCIT.

Deposition of pressurized suspension aerosols inhaled through extension devices

Only a small fraction of the dose from a pressurized aerosol inhaler reaches the lung, because most is deposited on the upper airways by inertial impaction. We have investigated the effects on aerosol deposition of two spacer devices (a 10-cm tube and a 22-cm cone) by incorporating teflon particles (mass median aerodynamic diameter, 3.2 micrometer) labeled with 99mTc into pressurized canisters. Ten subjects with obstructive airway disease inhaled the aerosol in a controlled manner from a conventional actuator alone or in combination with the tube or the cone. Radioaerosol distribution was measured using a shadowshield whole body counter. Deposition on the conducting airways was significantly improved by both spacers, but alveolar deposition was unchanged. Initial oropharyngeal deposition was reduced by both spacers in all 10 patients. We conclude that the spacer devices may have a role to play in aerosol therapy by increasing drug availability to the lung, while at the same time decreasing unwanted drug deposition in the oropharynx.

The first 5 years of the family clinic for HIV at Tygerberg Hospital: family demographics, survival of children and early impact of antiretroviral therapy

BACKGROUND

Family clinics address the problems of HIV-infected children and their families. The aims were to document demographics of the children and caregivers attending the Family Clinic for HIV at Tygerberg Academic Hospital (TAH) and to investigate factors affecting disease progression in children.

METHODS

A retrospective folder review of children and parents attending the Family Clinic at TAH between January 1997 and December 2001, a period noted for its lack of antiretroviral treatment.

RESULTS

Of 432 children seen for testing, 274 children, median age 16.9 months, were HIV-infected. During follow-up, 46 children died (median age 23 months) and 113 were lost to follow-up. The majority of children were malnourished. Those <2 years of age had lower weight for age Z-scores (WAZ) than older children (p<0.001). At presentation, 47 per cent were in clinical stage B and two-thirds had moderate or severe CD4+ T cell depletion. Seventeen children had received highly active antiretroviral therapy (HAART), 12 dual and 31 monotherapy. HAART was associated with improved survival compared to dual or monotherapy. Risk of death was reduced from eleven-fold for a WAZ <-4 to four-fold between -2 and -3. There was no association with immunological and clinical classification at entry and risk of mortality. Only 18 per cent of parents were evaluated in the clinic. Non-parental care was documented for 25 per cent of families.

CONCLUSIONS

A low WAZ is associated with poor survival in children. Nutritional status should receive more attention in HIV disease classification in children. Parent utilization of the clinic was inadequate. Even in the absence of HAART, extended survival in children is possible.

Association of asthma with a functional promoter polymorphism in the IL16 gene

BACKGROUND

IL-16, a multifunctional cytokine with increased expression in the airways of asthmatic subjects, inhibits allergic airway inflammation in animal models. A T-->C single nucleotide polymorphism (SNP) at the -295 position in the promoter region of the IL16 gene has been described.

OBJECTIVE

We sought to examine the functional significance of this promoter SNP and its relationship to asthma.

METHODS

We examined the effect of the -295 SNP on promoter activity in cell-line (HBE4-E6/E7) transfection experiments. We investigated the association of the IL16 -295 genotype with asthma among 341 affected sib-pair white families and 184 unrelated nonasthmatic control subjects. We analyzed the association between the IL16 genotype and asthma using family-based association test and case-control analyses.

RESULTS

In in vitro transfection experiments the T allele in the -295 position was associated with substantially reduced promoter activity compared with the C allele. In the family study the more common T allele at the -295 position was significantly associated with all asthma phenotypes (P = .002 to P = .015). In the case-control analysis asthmatic subjects were more likely than unrelated nonasthmatic control subjects to have the -295 TT genotype, but this did not reach statistical significance (odds ratio, 1.36; 95% CI, 0.92-2.02).

CONCLUSIONS

The T allele at the -295 position in the IL16 promoter region is associated with reduced promoter activity relative to the C allele and with asthma in this white population. Further investigation is needed to delineate the mechanisms underlying these findings and the relationship of the IL16 -295 genotype to asthma in other populations.

Exogenous interleukin-16 inhibits antigen-induced airway hyper-reactivity, eosinophilia and Th2-type cytokine production in mice

BACKGROUND

IL-16 has been described as a natural soluble CD4-ligand with immunosuppressive effects in vitro. However, little is known about the effect of IL-16 on immune responses in vivo.

OBJECTIVE

In the present study, we examined the effect of IL-16 administration in a murine model of allergic asthma. Next, we determined whether these effects were mediated by modulation of CD4+ T lymphocytes.

METHODS AND RESULTS

Intraperitoneal administration of IL-16 completely inhibits antigen-induced airway hyper-responsiveness and largely decreases the number of eosinophils in bronchoalveolar lavage fluid (> 90%) and airway tissue of ovalbumin-sensitized and challenged mice. Firstly, it appears that thoracic lymph node cells isolated from in vivo IL-16-treated ovalbumin-challenged animals produce less IL-4 (77%) and IL-5 (85%) upon antigenic re-stimulation, when compared to vehicle-treated mice. Secondly, pre-incubation of lymphocytes with IL-16 in vitro reduces antigen-induced proliferation (55%) and Th2-type cytokine production (IL-4; 56%, IL-5; 77%). Thirdly, the presence of IL-16 during priming cultures of TCR transgenic T cells (DO11.10), reduces IL-4 (33%) and IL-5 (35%), but not IL-10 and IFNgamma levels upon re-stimulation.

CONCLUSION

It can be concluded that IL-16 has potent immunosuppressive effects on a Th2dominated allergic airway response.

Malignant superior vena cava obstruction: stent placement via the subclavian route

Over a 3-year period 23 patients with malignant superior vena cava obstruction were referred for interventional management. They underwent repeat localized central venography and deployment of self-expanding Wallstents. All patients (age range 26-89 years) were approached by the subclavian route using 29 stents. The stent was used to exclude thrombus in the contralateral brachiocephalic vein in five patients and histologic information was available in all patients. Retrospective analysis of the clinical records was used to assess symptom-free survival and symptom recurrence. All patients reported an improvement in symptoms within 24 hr of the procedure. There was 100% technical success. Primary clinical success was achieved in 19 of 23 patients followed-up to their death with no symptom recurrence (range 1-34, mean 15 weeks). In four patients symptoms recurred but only one patient was referred for re-intervention, which was successful. Complications included single cases of early post-stent rethrombosis, distal slip on deployment, and distal slip on balloon dilatation. There were no puncture-related complications.

The fate of free male condoms distributed to the public in South Africa

OBJECTIVES

Public sector male condom distribution in South Africa rose from six million in 1994 to 198 million in 1999 as part of the government's condom promotion efforts for HIV/AIDS prevention. This study investigates what happens to the condoms which are distributed free of charge by the South African Department of Health.

METHODS

A prospective study was undertaken during 1998-1999 at 12 representative public health facilities. Five-hundred and fifty-four consecutive subjects leaving the facilities were recruited and followed-up for 5 weeks to ascertain the fate of the 8164 condoms they had procured.

RESULTS

A total of 384 participants (69.3%) and their 5528 condoms (67.7%) were followed successfully. After 5 weeks, 43.7% of the condoms had been used or broken in sex, 21.8% had been given away, 8.5% had been lost or discarded, and 26.0% were still available for use. Increased rates of condom use by participants were associated with active (compared to passive) condom procurement.

CONCLUSIONS

In light of the rapidly increasing number of free condoms being distributed by the public health service in South Africa, it is reassuring to note that wastage at 5 weeks is less than 10%. Extrapolating these data to the 198 million public sector condoms distributed in South Africa in 1999, at least 87 million condoms were used in sex. This methodology may be used to help evaluate the impact of existing condom distribution systems and the effectiveness of various condom promotion strategies.

Long-term survival after permanent pacemaker implantation in young adults: 30 year experience

The goal of the present study was to determine the etiology of conduction disease and long-term outcome for young adults who undergo permanent pacemaker implantation. Permanent pacing was performed in 232 patients aged 21-50 years, 135 males and 97 females, from 1965 through 1995. One hundred and twenty-six subjects (54%) had evidence of structural heart disease, while idiopathic conduction disease accounted for 46%. About half (54%) of 106 patients with structural heart disease had surgically induced heart block. Pacing mode at primary implantation was single chamber in 65% and dual chamber in 35%. Follow-up ranged from 12-387 months, with a mean of 104-months. At the last follow-up, 133 of 232 patients (57%) were alive, 40 (17%) had died, 30 (13%) were lost to follow-up, 26 (11%) were transferred elsewhere, and 3 (1%) explanted. Patients with sick sinus syndrome had similar outcomes to those with AV block. There was a sharp decline in survival during the first six months; 7.5% of the sample died within the first year following their first pacemaker operation. After the first year, the decline in survival slowed and 70% of the patients could be expected to survive beyond 20 years. The overall survival of young patients without structural heart disease who received a permanent pacemaker was comparable to an age- and sex-matched control population, while patients with structural heart disease performed significantly worse than the control population.

Glucocorticoid-resistant asthma: more than meets the eye

INTRODUCTION

For decades glucocorticoids have been considered as the gold standard for the treatment of asthma. We present a case report of typical glucocorticoid-resistant asthma and current consensus in definitions of "severe refractory", "difficult" and "glucocorticoid-resistant" asthma.

METHODS

Full-text papers and abstracts were identified on the basis of a comprehensive literature search primarily in MEDLINE (1966 to June 2012) but also in the Cochrane Central Register of Controlled Trials database.

RESULTS

Glucocorticoid-resistant asthmatics are a small subset of patients who pose noteworthy diagnostic challenges while contributing disproportionately to health care costs. Recognition of various asthma phenotypes has aided in characterizing groups with severe asthma and given a better understanding of its pathophysiological process. The molecular mechanism of glucocorticoid action is complicated and several pathways have been identified to explain drug resistance, which in turn is crucial for drug development. Tobacco smoking appears to be the single most important contributor of glucocorticoid resistance. We present the emerging and promising concepts in the management of glucocorticoid-resistant asthma, which mainly include drugs targeting specific molecules, receptors, inflammatory cells or immune processes.

CONCLUSION

The challenges in making a diagnosis of glucocorticoid-resistant asthma may contribute to underestimating its prevalence and impact on patient care. Considerable progress has been made in identifying distinct phenotypes and mechanisms of glucocorticoid resistance; therefore the future of new drug development in management of asthma is promising.

Aeroallergen Sensitization, Serum IgE, and Eosinophilia as Predictors of Response to Omalizumab Therapy During the Fall Season Among Children with Persistent Asthma

BACKGROUND

Perennial aeroallergen sensitization is associated with greater asthma morbidity and is required for treatment with omalizumab.

OBJECTIVE

To investigate the predictive relationship between the number of aeroallergen sensitizations, total serum IgE, and serum eosinophil count, and response to omalizumab in children and adolescents with asthma treated during the fall season.

METHODS

This analysis includes inner-city patients with persistent asthma and recent exacerbations aged 6-20 years comprising the placebo- and omalizumab-treated groups in 2 completed randomized clinical trials, the Inner-City Anti-IgE Therapy for Asthma study and the Preventative Omalizumab or Step-Up Therapy for Fall Exacerbations study. Logistic regression modeled the relationship between greater degrees of markers of allergic inflammation and the primary outcome of fall season asthma exacerbations.

RESULTS

The analysis included 761 participants who were 62% male and 59% African American with a median age of 10 years. Fall asthma exacerbations were significantly higher in children with greater numbers of aeroallergen-specific sensitizations in the placebo group (odds ratio [OR], 1.33; 95% confidence interval [CI], 1.11-1.60; P < .01), but not in the omalizumab-treated children (OR, 1.08; 95% CI, 0.91-1.28; P = .37), indicating a significant differential effect (P < .01). Likewise, there was a differential effect of omalizumab treatment in children with greater baseline total serum IgE levels (P < .01) or greater baseline serum eosinophil counts (P < .01). Multiple aeroallergen sensitization was the best predictor of response to omalizumab; treated participants sensitized to ≥4 different groups of aeroallergens had a 51% reduction in the odds of a fall exacerbation (OR, 0.49; 95% CI, 0.30-0.81; P < .01).

CONCLUSIONS

In preventing fall season asthma exacerbations, treatment with omalizumab was most beneficial in children with a greater degree of allergic inflammation.

Multiple abnormalities in the ultraviolet light response of cultured fibroblasts derived from patients with the basal cell nevus syndrome

Basal Cell Nevus Syndrome (BCNS) is a rare autosomal-dominant inherited disorder associated with a marked hypersusceptibility to spontaneous and radiation-induced skin cancer. We examined the changes in cell survival, unscheduled DNA synthesis (UDS) and the frequency of sister chromatid exchanges (SCE) induced by ultraviolet light (UVL) in confluent normal and BCNS fibroblasts. BCNS cells appeared slightly hypersensitive to the cytotoxic effects of UVL. The rate of UDS induced by UVL exposure in normal cell strains increased linearly following doses up to 30 J/m2, whereas in BCNS cells UDS became saturated at doses of 10 J/m2 showing no further increase with doses up to 30 J/m2. UDS activity persisted for longer periods after UVL exposure in BCNS as compared with normal cells. The dose-response relationship for UVL-induced SCE was similar in normal and BCNS fibroblasts. However, the frequencies of UVL-induced SCE declined to near background levels in normal cells following 12-24 hr of confluent holding prior to subculture whereas they remained elevated in BCNS cells with holding times up to 24 hr after UVL exposure. Overall, these results suggest that BCNS fibroblasts may have a diminished capacity for the repair of some type of DNA damage as compared with normal fibroblasts.

Improving the accessibility of condoms in South Africa: the role of informal distribution

Lack of access to condoms presents a fundamental barrier to HIV prevention across most of sub-Saharan Africa. One strategy to enhance the accessibility of condoms is to promote their informal distribution outside of health facilities through existing social networks. To investigate the prevalence and practices of informal condom distribution, we administered a questionnaire to individuals procuring condoms at 12 public health facilities in four regions of South Africa. Of the 554 individuals interviewed, 269 (48%) reported either giving or receiving condoms informally in the month before the study. In multivariate analysis, reporting informal condom distribution was associated with increased education, male gender, multiple sex partners and recent condom use. The specific practices involved in giving or receiving condoms differed between males and females, with women more likely to involve family members and men more likely to involve friends. These results indicate that informal condom distribution is surprisingly common among individuals procuring public sector condoms in South Africa, and begin to suggest the gendered nature of informal condom distribution networks. While these findings require confirmation in other populations, the practices of informal condom distribution described here provide an excellent opportunity for enhancing condom accessibility and delivering other interventions for HIV prevention.