Metabolic flexibility as a major predictor of spatial distribution in microbial communities

A better understand the ecology of microbes and their role in the global ecosystem could be achieved if traditional ecological theories can be applied to microbes. In ecology organisms are defined as specialists or generalists according to the breadth of their niche. Spatial distribution is often used as a proxy measure of niche breadth; generalists have broad niches and a wide spatial distribution and specialists a narrow niche and spatial distribution. Previous studies suggest that microbial distribution patterns are contrary to this idea; a microbial generalist genus (Desulfobulbus) has a limited spatial distribution while a specialist genus (Methanosaeta) has a cosmopolitan distribution. Therefore, we hypothesise that this counter-intuitive distribution within generalist and specialist microbial genera is a common microbial characteristic. Using molecular fingerprinting the distribution of four microbial genera, two generalists, Desulfobulbus and the methanogenic archaea Methanosarcina, and two specialists, Methanosaeta and the sulfate-reducing bacteria Desulfobacter were analysed in sediment samples from along a UK estuary. Detected genotypes of both generalist genera showed a distinct spatial distribution, significantly correlated with geographic distance between sites. Genotypes of both specialist genera showed no significant differential spatial distribution. These data support the hypothesis that the spatial distribution of specialist and generalist microbes does not match that seen with specialist and generalist large organisms. It may be that generalist microbes, while having a wider potential niche, are constrained, possibly by intrageneric competition, to exploit only a small part of that potential niche while specialists, with far fewer constraints to their niche, are more capable of filling their potential niche more effectively, perhaps by avoiding intrageneric competition. We suggest that these counter-intuitive distribution patterns may be a common feature of microbes in general and represent a distinct microbial principle in ecology, which is a real challenge if we are to develop a truly inclusive ecology

Seeing the baby, doing family: commercial ultrasound as family practice?

Medical sociologists and anthropologists have studied the social significance of obstetric ultrasound for families but little is known about how women and families make use of commercially available ultrasound scans. This article draws on interviews with women who booked a scan with a commercial company in the UK. For some women, commercial ultrasound can be understood as a family practice. We investigate this theme by examining who accompanies women to commercial scan appointments, how scan images are shared and how sonograms are used as prompts to resemblance talk. We argue that commercial scans are more than an additional opportunity to acquire ‘baby’s first picture’ and offer a flexible resource to do family, creating and affirming family relationships and rehearsing roles as parents, siblings and grandparents. Our findings confirm the importance of imagination in doing family and raise questions about the role of technology and commercial interests in shaping family practices

Physically active academic lessons; Acceptance, barriers and facilitators for implementation

Background To improve health and academic learning in schoolchildren, the Active School programme in Stavanger, Norway has introduced physically active academic lessons. This is a teaching method combining physical activity with academic content. The purpose of this paper was to evaluate the response to the physically active lessons and identify facilitators and barriers for implementation of such an intervention. Methods Five school leaders (principals or vice-principals), 13 teachers and 30 children from the five intervention schools were interviewed about their experiences with the 10-month intervention, which consisted of weekly minimum 2 × 45 minutes of physically active academic lessons, and the factors affecting its implementation. All interviews were transcribed and analysed using the qualitative data analysis program NVivo 10 (QSR international, London, UK). In addition, weekly teacher’s intervention delivery logs were collected and analysed. Results On average, the physically active academic lessons in 18 of the 34 weeks (53%) were reported in the teacher logs. The number of delivered physically active academic lessons covered 73% of the schools’ planned activity. Physically active lessons were well received among school leaders, teachers and children. The main facilitators for implementation of the physically active lessons were active leadership and teacher support, high self-efficacy regarding mastering the intervention, ease of organizing physically active lessons, inclusion of physically active lessons into the lesson curricula, and children’s positive reception of the intervention. The main barriers were unclear expectations, lack of knowledge and time to plan the physiclly active lessons, and the length of the physically active lessons (15–20 min lessons were preferred over the 45 min lessons). Conclusion Physically active academic lessons were considered an appropriate pedagogical method for creating positive variation, and were highly appreciated among both teachers and children. Both the principal and the teachers should be actively involved the implementation, which could be strengthened by including physical activity into the school’s strategy. Barriers for implementing physically active lessons in schools could be lowered by increasing implementation clarity and introducing the teachers to high quality and easily organized lessons.publishedVersio

How Mistimed and Unwanted Pregnancies Affect Timing of Antenatal Care Initiation in three Districts in Tanzania

Early antenatal care (ANC) initiation is a doorway to early detection and management of potential complications associated with pregnancy. Although the literature reports various factors associated with ANC initiation such as parity and age, pregnancy intentions is yet to be recognized as a possible predictor of timing of ANC initiation. Data originate from a cross-sectional household survey on health behaviour and service utilization patterns. The survey was conducted in 2011 in Rufiji, Kilombero and Ulanga districts in Tanzania on 910 women of reproductive age who had given birth in the past two years. ANC initiation was considered to be early only if it occurred in the first trimester of pregnancy gestation. A recently completed pregnancy was defined as mistimed if a woman wanted it later, and if she did not want it at all the pregnancy was termed as unwanted. Chisquare was used to test for associations and multinomial logistic regression was conducted to examine how mistimed and unwanted pregnancies affect timing of ANC initiation. Although 49.3% of the women intended to become pregnant, 50.7% (34.9% mistimed and 15.8% unwanted) became pregnant unintentionally. While ANC initiation in the 1st trimester was 18.5%, so was 71.7% and 9.9% in the 2nd and 3rd trimesters respectively. Multivariate analysis revealed that ANC initiation in the 2nd trimester was 1.68 (95% CI 1.10‒2.58) and 2.00 (95% CI 1.05‒3.82) times more likely for mistimed and unwanted pregnancies respectively compared to intended pregnancies. These estimates rose to 2.81 (95% CI 1.41‒5.59) and 4.10 (95% CI 1.68‒10.00) respectively in the 3rd trimester. We controlled for gravidity, age, education, household wealth, marital status, religion, district of residence and travel time to a health facility. Late ANC initiation is a significant maternal and child health consequence of mistimed and unwanted pregnancies in Tanzania. Women should be empowered to delay or avoid pregnancies whenever they need to do so. Appropriate counseling to women, especially those who happen to conceive unintentionally is needed to minimize the possibility of delaying ANC initiation.\u

Eosinophilic myocarditis mimicking acute coronary syndrome secondary to idiopathic hypereosinophilic syndrome: a case report

<p>Abstract</p> <p>Introduction</p> <p>Eosinophilic myocarditis is a rare form of myocarditis. It is characterized pathologically by diffuse or focal myocardial inflammation with eosinophilic infiltration, often in association with peripheral blood eosinophilia. We report a case of eosinophilic myocarditis secondary to hypereosinophilic syndrome.</p> <p>Case presentation</p> <p>A 74-year-old Caucasian woman with a history of asthma, paroxysmal atrial fibrillation, stroke and coronary artery disease presented to the emergency department of our hospital with chest pain. Evaluations revealed that she had peripheral blood eosinophilia and elevated cardiac enzymes. Electrocardiographic findings were nonspecific. Her electrocardiographic finding and elevated cardiac enzymes pointed to a non-ST-elevated myocardial infarction. Echocardiogram showed a severe decrease in the left ventricular systolic function. Coronary angiogram showed nonobstructive coronary artery disease. She then underwent cardiac magnetic resonance imaging, which showed neither infiltrative myocardial diseases nor any evidence of infarction. This was followed by an endomyocardial biopsy which was consistent with eosinophilic myocarditis. Hematologic workup regarding her eosinophilia was consistent with hypereosinophilic syndrome. After being started on steroid therapy, her peripheral eosinophilia resolved and her symptoms improved. Her left ventricular ejection fraction, however, did not improve.</p> <p>Conclusion</p> <p>Eosinophilic myocarditis can present like an acute myocardial infarction and should be considered in the differential diagnosis of acute coronary syndrome in patients with a history of allergy, asthma or acute reduction of the left ventricular function with or without peripheral eosinophilia.</p

Socioeconomic status and prostate cancer incidence and mortality rates among the diverse population of California

The racial/ethnic disparities in prostate cancer rates are well documented, with the highest incidence and mortality rates observed among African-Americans followed by non-Hispanic Whites, Hispanics, and Asian/Pacific Islanders. Whether socioeconomic status (SES) can account for these differences in risk has been investigated in previous studies, but with conflicting results. Furthermore, previous studies have focused primarily on the differences between African-Americans and non-Hispanic Whites, and little is known for Hispanics and Asian/Pacific Islanders. To further investigate the relationship between SES and prostate cancer among African-Americans, non-Hispanic Whites, Hispanics, and Asian/Pacific Islanders, we conducted a large population-based cross-sectional study of 98,484 incident prostate cancer cases and 8,997 prostate cancer deaths from California. Data were abstracted from the California Cancer Registry, a population-based surveillance, epidemiology, and end results (SEER) registry. Each prostate cancer case and death was assigned a multidimensional neighborhood-SES index using the 2000 US Census data. SES quintile-specific prostate cancer incidence and mortality rates and rate ratios were estimated using SEER*Stat for each race/ethnicity categorized into 10-year age groups. For prostate cancer incidence, we observed higher levels of SES to be significantly associated with increased risk of disease [SES Q1 vs. Q5: relative risk (RR) = 1.28; 95% confidence interval (CI): 1.25–1.30]. Among younger men (45–64 years), African-Americans had the highest incidence rates followed by non-Hispanic Whites, Hispanics, and Asian/Pacific Islanders for all SES levels. Yet, among older men (75–84 years) Hispanics, following African-Americans, displayed the second highest incidence rates of prostate cancer. For prostate cancer deaths, higher levels of SES were associated with lower mortality rates of prostate cancer deaths (SES Q1 vs. Q5: RR = 0.88; 95% CI: 0.92–0.94). African-Americans had a twofold to fivefold increased risk of prostate cancer deaths in comparison to non-Hispanic Whites across all levels of SES. Our findings suggest that SES alone cannot account for the greater burden of prostate cancer among African-American men. In addition, incidence and mortality rates of prostate cancer display different age and racial/ethnic patterns across gradients of SES

Age-associated mitochondrial DNA mutations cause metabolic remodelling that contributes to accelerated intestinal tumorigenesis.

Oxidative phosphorylation (OXPHOS) defects caused by somatic mitochondrial DNA (mtDNA) mutations increase with age in human colorectal epithelium and are prevalent in colorectal tumours, but whether they actively contribute to tumorigenesis remains unknown. Here we demonstrate that mtDNA mutations causing OXPHOS defects are enriched during the human adenoma/carcinoma sequence, suggesting they may confer a metabolic advantage. To test this we deleted the tumour suppressor Apc in OXPHOS deficient intestinal stem cells in mice. The resulting tumours were larger than in control mice due to accelerated cell proliferation and reduced apoptosis. We show that both normal crypts and tumours undergo metabolic remodelling in response to OXPHOS deficiency by upregulating the de novo serine synthesis pathway (SSP). Moreover, normal human colonic crypts upregulate the SSP in response to OXPHOS deficiency prior to tumorigenesis. Our data show that age-associated OXPHOS deficiency causes metabolic remodelling that can functionally contribute to accelerated intestinal cancer development

The Functions of Myosin II and Myosin V Homologs in Tip Growth and Septation in Aspergillus nidulans

Because of the industrial and medical importance of members of the fungal genus Aspergillus, there is considerable interest in the functions of cytoskeletal components in growth and secretion in these organisms. We have analyzed the genome of Aspergillus nidulans and found that there are two previously unstudied myosin genes, a myosin II homolog, myoB (product = MyoB) and a myosin V homolog, myoE (product = MyoE). Deletions of either cause significant growth defects. MyoB localizes in strings that coalesce into contractile rings at forming septa. It is critical for septation and normal deposition of chitin but not for hyphal extension. MyoE localizes to the Spitzenkörper and to moving puncta in the cytoplasm. Time-lapse imaging of SynA, a v-SNARE, reveals that in myoE deletion strains vesicles no longer localize to the Spitzenkörper. Tip morphology is slightly abnormal and branching occurs more frequently than in controls. Tip extension is slower than in controls, but because hyphal diameter is greater, growth (increase in volume/time) is only slightly reduced. Concentration of vesicles into the Spitzenkörper before incorporation into the plasma membrane is, thus, not required for hyphal growth but facilitates faster tip extension and a more normal hyphal shape