Hyperoxia and apoptosis in developing mouse lung mesenchyme

Hyperoxia contributes to the development of bronchopulmonary dysplasia in former premature infants. Injurious environmental factors such as hyperoxia may disrupt distal airway branching and alveolar septation, as these critical stages in lung development occur following birth in extremely premature infants. To test if hyperoxia directly inhibited distal airway branching, we cultured E16 fetal mouse lung explants in either 20% (control) or 95% oxygen (hyperoxia). Hyperoxia reduced the number of distal airways to less than 50% of controls. Explants cultured in 95% oxygen also had fewer complex distal airways compared with controls. Mesenchymal cells adjacent to distal airways in hyperoxic explants appeared apoptotic by phase microscopy. Consistent with increased apoptosis, explants cultured in hyperoxia had increased caspase 3/7 activity compared with controls. Hyperoxia also increased mesenchymal caspase 3 expression and annexin V binding within cultured explants as visualized by fluorescence microscopy. We measured increased annexin V binding in isolated primary fetal lung mesenchymal cells cultured in 95% oxygen suggesting a direct effect on cells within the mesenchyme. Hyperoxia can lead to NF-kappaB activation, which mediates inflammatory cascades and may protect cells from apoptosis. We detected NF-kappaB activation and nuclear p65 localization in explants exposed to 48 h of hyperoxia. Inhibition of NF-kappaB prevented the hyperoxia-induced activation of caspase 3. NF-kappaB activation may therefore contribute to apoptosis in the developing fetal mouse lung following hyperoxia exposure. Our data suggest hyperoxia inhibits distal airway branching and directly induces apoptosis of the fetal mouse lung mesenchyme.     

The impact of HIV infection and trimethoprim-sulphamethoxazole prophylaxis on bacterial isolates from children with community-acquired pneumonia in South Africa

The aim of this study was to compare the type and antimicrobial resistance patterns of bacteria cultured from blood or respiratory tract secretions by HIV status and the use of trimethoprim-sulphamethoxazole (TMP-SMX) prophylaxis in children hospitalized with community-acquired pneumonia. During a 1-year prospective study in Cape Town, South Africa, 250 children [median aged 6 (3-16) months] hospitalized with pneumonia were enrolled; 151 (60.4 per cent) were HIV-infected. The incidence of bacteremia [35 of 244 cultures (14.3 per cent)] did not differ by HIV status. Bacteria were cultured in 17 of 32 (53 per cent) bronchoalveolar lavage specimens (BAL), 128 of 210 (61 per cent) induced sputa and 166 of 231 (71 per cent) nasopharyngeal specimens (NPAs). The type and number of bacteria in respiratory secretions did not differ by HIV status, except for a higher rate of Staphylococcus aureus in sputum or BAL [22 of 146 (15 per cent) vs. 3 of 96 (3 per cent), p = 0.003] and NPAs [41 of 135 (30 per cent) vs. 9 of 96 (9 per cent), p < 0.001] of HIV-positive children. The use of TMP-SMX prophylaxis in HIV-infected children was associated with an increased nasopharyngeal carriage of S. aureus [22 of 51 (43 per cent) vs. 17 of 79 (22 per cent), p = 0.009]. The rising prevalence of HIV infection and the use of TMP-SMX prophylaxis may alter the spectrum of colonizing and pathogenic bacteria in children in developing countries.     

Cardiac sarcoidosis: Recurrent disease in a heart transplant patient following pulmonary tuberculosis infection

Cardiac transplantation is indicated for patients with end-stage cardiomyopathy secondary to cardiac sarcoidosis. Although rare, recurrent disease has been reported in two cases. The current report presents a case of recurrent cardiac sarcoidosis in a patient 45 months postorthotopic heart transplantation and 40 months following reactivation of latent Mycobacterium tuberculosis infection. The patient was the first to have recurrent disease following an infection that has been proposed to be involved in its pathogenesis. The patient’s interval between transplant and recurrence is the longest reported to date.     

Autoimmune haemolytic anaemia associated with mantle cell lymphoma

Autoimmune haemolytic anaemia (AIHA) is a well-recognised complication of lymphoproliferative disorders, and has been reported in association with all B and T cell non-Hodgkin lymphoma subtypes with the exception of mantle cell lymphoma (MCL). We describe herein a case of MCL diagnosed in an initially asymptomatic 66-year-old woman who developed transfusion-dependent AIHA 6 months later coincident with lymphoma progression. The AIHA failed to respond satisfactorily to conventional treatment (high-dose oral prednisolone) but rapidly resolved following commencement of non-rituximab-containing combination chemotherapy in parallel with complete remission of the lymphoma. This is the first of such cases to be described in the literature and confirms that the immune environment of MCL can predispose to AIHA in the same way as in other lymphoma subtypes. Despite this being an infrequent occurrence, clinicians should be aware that AIHA is a potential complication of MCL and may be more successfully controlled by treating the underlying lymphoma rather than relying on conventional anti-haemolytic strategies such as steroids.     

Factors associated with higher oxytocin requirements in labor

Objective: To identify clinical characteristics associated with high maximum oxytocin doses in women who achieve complete cervical dilation.

Methods: A retrospective nested case-control study was performed within a cohort of all term women at a single center between 2004 and 2008 who reached the second stage of labor. Cases were defined as women who had a maximum oxytocin dose during labor >20?mu/min, while women in the control group had a maximum oxytocin dose during labor of ≤20?mu/min. Exclusion criteria included no oxytocin administration during labor, multiple gestations, major fetal anomalies, nonvertex presentation, and prior cesarean delivery. Multiple maternal, fetal, and labor factors were evaluated with univariable analysis and multivariable logistic regression.

Results: Maximum oxytocin doses >20?mu/min were administered to 108 women (3.6%), while 2864 women received doses ≤20?mu/min. Factors associated with higher maximum oxytocin dose after adjusting for relevant confounders included maternal diabetes, birthweight >4000?g, intrapartum fever, administration of magnesium, and induction of labor.

Conclusions: Few women who achieve complete cervical dilation require high doses of oxytocin. We identified maternal, fetal and labor factors that characterize this group of parturients.     

Gametes, consent and points of no return

Disputes over stored embryos are inevitably difficult to resolve, as we have seen in the case of Natalie Evans and Howard Johnston. The Department of Health is currently reviewing the Human Fertilisation and Embryology Act 1990 following a public consultation in August 2005. In this paper, I will argue that the Act should be amended so that the point of no return for withdrawal of consent to the use of gametes is the creation of an embryo with those gametes (fertilization). By point of no return, I mean the point at which donors/providers should no longer be able to withdraw consent. I will argue that no distinction should be drawn between donors--those who give gametes for others to use for procreative purposes--and providers--those who use their own gametes for their own procreative purposes. I will also look at how egg-sharers (who both donate and provide gametes) should be regarded, and whether an exception should be made for embryo donors.     

Structure-based design, synthesis, and biological evaluation of inhibitors of Mycobacterium tuberculosis type II dehydroquinase

The syntheses by Suzuki cross-coupling of 12 5-aryl analogues of the known inhibitor (1R,3R,4R)-1,3,4-trihydroxycyclohex-5-en-1-carboxylic acid are reported. These compounds were found to be reversible competitive inhibitors against Mycobacterium tuberculosis type II dehydroquinase, the third enzyme of the shikimic acid pathway. The most potent inhibitor, the 3-nitrophenyl derivative, has a K(i) of 54 nM, over 180 times more potent than the reported inhibitor (1R,3R,4R)-5-fluoro-1,3,4-trihydroxycyclohex-5-en-1-carboxylic acid and more than 700 times lower than the K(M) of the substrate, making it the most potent known inhibitor against any type II dehydroquinase. Docking studies using GOLD (version 2.2) indicated a key electrostatic binding interaction between the aromatic rings and Arg19, a residue that has been identified as essential for enzyme activity.     

Provider-pharmacist education and adherence rates for the oral typhoid vaccine: a pilot study

In 2002, 35 travelers were surveyed regarding the travel medicine provider and pharmacist education they received, along with self-reported adherence rates for the Ty21a vaccine. The results demonstrated that pharmacy education is minimal and that computerized pharmacy education handouts were not considered helpful by these travelers. Complete adherence was reported at 49%.     

Vaccine coverage in children born to migrant mothers in Australia: A population-based cohort study

BackgroundOverall, infant immunisation coverage is currently >90% in Australia, but there are pockets of under-immunised children including children from migrant backgrounds. This study aimed to examine whether on-time vaccination coverage of diphtheria-tetanus-pertussis dose 3 (DTP3) for children born in Australia differed by mother’s region of birth and if so, what factors were associated with these differences.MethodsWe conducted a population-based cohort study using linked data on perinatal, immunisation and birth records for 2 million children born in Western Australia and New South Wales between 1996 and 2012. We assessed on-time coverage of DTP3 (vaccination from 2 weeks prior to, and up until 30 days after, the due date) in children with mothers born overseas. Logistic regression models were developed to determine factors associated with on-time coverage for each maternal region of birth and all regions combined, adjusting for a range of demographic factors. Adjusted estimates of coverage were calculated for the different regions of birth.ResultsOn-time DTP3 coverage was 76.2% in children of Australian born mothers, lower in children of mothers from Oceania (66.7%) and North America (68%), and higher in children born to mothers from South-East Asia (79.9%) and Southern Asia (79.3%). While most variables were consistently associated with lower coverage in all regions of birth, higher socioeconomic status and jurisdiction of birth showed varied results. Adjusted estimates of DTP3 coverage increased in children born to mothers from Australia (78.3%), Oceania (70.5%), Northern Africa (81.5%) and the Middle East (79.6%). DTP3 coverage decreased in children born to mothers from Europe and former USSR (74.6%), North-east Asia (75.2%), Southern Asia (76.7%), North America (65.5) and South/Central America and the Caribbean (73.2%).ConclusionsOn-time vaccination rates differed by mother’s region of birth. More research is needed to determine the main reasons for these remaining differences to improve vaccine uptake and also help guide policy and practice.