Global Health Outreach: Organizing a Book Drive for Malawi

This presentation describes the organization of a book drive for the Malawi College of Health Sciences in Blantyre, Malawi. The College’s library serves about 700 students, as well as healthcare professionals from a neighboring hospital. However, the library lacks sufficient resources, with most of their books being outdated or in poor condition, diminishing health care quality in Malawi.https://digitalrepository.unm.edu/hslic-posters-presentations/1077/thumbnail.jp

Duration of shedding of respiratory syncytial virus in a community study of Kenyan children

Background: Our understanding of the transmission dynamics of respiratory syncytial virus (RSV) infection will be better informed with improved data on the patterns of shedding in cases not limited only to hospital admissions. Methods: In a household study, children testing RSV positive by direct immunofluorescent antibody test (DFA) were enrolled. Nasal washings were scheduled right away, then every three days until day 14, every 7 days until day 28 and every 2 weeks until a maximum of 16 weeks, or until the first DFA negative RSV specimen. The relationship between host factors, illness severity and viral shedding was investigated using Cox regression methods. Results: From 151 families a total of 193 children were enrolled with a median age of 21 months (range 1-164 months), 10% infants and 46% male. The rate of recovery from infection was 0.22/person/day (95% CI 0.19-0.25) equivalent to a mean duration of shedding of 4.5 days (95%CI 4.0-5.3), with a median duration of shedding of 4 days (IQR 2-6, range 1-14). Children with a history of RSV infection had a 40% increased rate of recovery i.e. shorter duration of viral shedding (hazard ratio 1.4, 95% CI 1.01-1.86). The rate of cessation of shedding did not differ significantly between males and females, by severity of infection or by age. Conclusion: We provide evidence of a relationship between the duration of shedding and history of infection, which may have a bearing on the relative role of primary versus re-infections in RSV transmission in the community

Negative Subtraction Hybridization: An efficient method to isolate large numbers of condition-specific cDNAs

BACKGROUND: The construction of cDNA libraries is a useful tool to understand gene expression in organisms under different conditions, but random sequencing of unbiased cDNA collections is laborious and can give rise to redundant EST collections. We aimed to isolate cDNAs of messages induced by switching Aspergillus nidulans from growth on glucose to growth on selected polysaccharides. Approximately 4,700 contigs from 12,320 ESTs were already available from a cDNA library representing transcripts isolated from glucose-grown A. nidulans during asexual development. Our goals were to expand the cDNA collection without repeated sequencing of previously identified ESTs and to find as many transcripts as possible that are specifically induced in complex polysaccharide metabolism. RESULTS: We have devised a Negative Subtraction Hybridization (NSH) method and tested it in A. nidulans. NSH entails screening a plasmid library made from cDNAs prepared from cells grown under a selected physiological condition with labeled cDNA probes prepared from another physiological condition. Plasmids with inserts that failed to hybridize to cDNA probes through two rounds of screening (i.e. negatives) indicate that they are transcripts present at low concentration in the labeled probe pool. Thus, these transcripts will be predominantly condition-specific, along with some rare transcripts. In a screen for transcripts induced by switching the carbon source from glucose to 12 selected polysaccharides, 3,532 negatives were isolated from approximately 100,000 surveyed colonies using this method. Negative clones were end-sequenced and assembled into 2,039 contigs, of which 1,722 were not present in the previously characterized glucose-grown cDNA library. Single-channel microarray hybridization experiments confirmed that the majority of the negatives represented genes that were differentially induced by a switch from growth in glucose to one or more of the polysaccharides. CONCLUSIONS: The Negative Subtraction Hybridization method described here has several practical benefits. This method can be used to screen any existing cDNA library, including full-length and pooled libraries, and does not rely on PCR or sequence information. In addition, NSH is a cost-effective method for the isolation of novel, full-length cDNAs for differentially expressed transcripts or enrichment of rare transcripts

Genetic relatedness of infecting and reinfecting respiratory syncytial virus strains identified in a birth cohort from rural Kenya

Background: Respiratory syncytial virus (RSV) reinfects individuals repeatedly. The extent to which this is a consequence of RSV antigenic diversity is unclear. Methods: Six-hundred thirty-five children from rural Kenya were closely monitored for RSV infection from birth through 3 consecutive RSV epidemics. RSV infections were identified by immunofluorescence testing of nasal washing samples collected during acute respiratory illnesses, typed into group A and B, and sequenced in the attachment (G) protein. A positive sample separated from a previous positive by ≥14 days was defined as a reinfection a priori. Results: Phylogenetic analysis was undertaken for 325 (80%) of 409 identified infections, including 53 (64%) of 83 reinfections. Heterologous group reinfections were observed in 28 episodes, and homologous group reinfections were observed in 25 episodes; 10 involved homologous genotypes, 5 showed no amino acid changes, and 3 were separated by 21–24 days and were potentially persistent infections. The temporal distribution of genotypes among reinfections did not differ from that of single infections. Conclusions: The vast majority of infection and reinfection pairs differed by group, genotype, or G amino acid sequence (ie, comprised distinct viruses). The extent to which this is a consequence of immune memory of infection history or prevalent diversity remains unclear

Reconstructed human pigmented skin/epidermis models achieve epidermal pigmentation through melanocore transfer

Funding: We thank the Electron Microscopy Facility at the Instituto Gulbenkian de Ciência, the Pathological Anatomy service in the Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG) and the Histology Facility at CEDOC for technical assistance. This project was supported by Fundação para a Ciência e a Tecnologia (FCT), Portugal through FCT Unit iNOVA4Health – UIDB/04462/2020 and UIDP/04462/2020, a programme financially supported by FCT / Ministério da Ciência, Tecnologia e Ensino Superior, through national funds, grant PTDC/BIA-CEL/29765/2017, PhD fellowships 2020.08528.BD (SLV), PD/BD/128164/2016, PD/BD/137442/2018 (MVN) and PD/BD/136905/2018 (JC) and the FCT Investigator Program to DCB (IF/00501/2014/CP1252/CT0001).The skin acts as a barrier to environmental insults and provides many vital functions. One of these is to shield DNA from harmful UV radiation, which is achieved by skin pigmentation arising as melanin is produced and dispersed within the epidermal layer. This is a crucial defence against DNA damage, photo-ageing and skin cancer. The mechanisms and regulation of melanogenesis and melanin transfer involve extensive crosstalk between melanocytes and keratinocytes in the epidermis, as well as fibroblasts in the dermal layer. Although the predominant mechanism of melanin transfer continues to be debated and several plausible models have been proposed, we and others previously provided evidence for a coupled exo/phagocytosis model. Herein, we performed histology and immunohistochemistry analyses and demonstrated that a newly developed full-thickness 3D reconstructed human pigmented skin model and an epidermis-only model exhibit dispersed pigment throughout keratinocytes in the epidermis. Transmission electron microscopy revealed melanocores between melanocytes and keratinocytes, suggesting that melanin is transferred through coupled exocytosis/phagocytosis of the melanosome core, or melanocore, similar to our previous observations in human skin biopsies. We therefore present evidence that our in vitro models of pigmented human skin show epidermal pigmentation comparable to human skin. These findings have a high value for studies of skin pigmentation mechanisms and pigmentary disorders, whilst reducing the reliance on animal models and human skin biopsies.publishersversionepub_ahead_of_prin

Workplace Turbulence and Workforce Preparedness

The year 1973 marked a divide in the postwar economy.1 During the 25 years between 1948 and 1973, private sector productivity increased at an annual rate of 2.9%. Productivity improvement after 1973 fell way below this long-term trend, leveling off at about 0.6% a year until 1981 and rising to only 1.6% a year between 1981 and 1987. A similar pattern is reflected in the real wages of the workforce.2The conventional interpretation of this difference in the U.S. economy before and after 1973 is that it reflects the combined influence of the OPEC oil shock and the influx into the labor market of inexperienced workers born in the postwar baby boom, possibly reinforced by growth in regulatory costs.3 However, when the productivity data are analyzed in a growth accounting framework, these economic factors can only account for about two thirds of the productivity decline.4 What then explains the balance of the shortfall in productivity? Many analysts have pointed to the intangible effects on managers of increased economic uncertainty since 1973—growing business cautiousness, increased emphasis on short-term financial objectives, and inadequate entrepreneurial incentives.5 But economic change and uncertainty can also affect productivity through their impact on jobs and workers

Seasonal dynamics of tetracycline resistance gene flux in the Sumas River agricultural watershed of British Columbia, Canada

Environmental transport of contaminants that can influence the development of antibiotic resistance in bacteria is an important concern in the management of ecological and human health risks. Agricultural regions are locales where practices linked to food crop and livestock production can introduce contaminants that could alter the selective pressures for the development of antibiotic resistance in microbiota. This is important in regions where the use of animal manure or municipal biosolids as waste and/or fertilizer could influence selection for antibiotic resistance in pathogenic bacterial species. To investigate the environmental transport of contaminants that could lead to the development of antibiotic resistance in bacteria, a watershed with one of the highest levels of intensity of agricultural activity in Canada was studied; the Sumas River located 60 km east of Vancouver, British Columbia. This two-year assessment monitored four selected tetracycline resistance genes (tet(O), tet(M), tet(Q), tet(W)) and water quality parameters (temperature, specific conductivity, turbidity, suspended solids, nitrate, phosphate and chloride) at eight locations across the watershed. The tetracycline resistance genes (Tcr) abundances in the Sumas River network ranged between 1.47 × 102 and 3.49 × 104 copies/mL and ranged between 2.3 and 6.9 copies/mL in a control stream (located far from agricultural activities) for the duration of the study. Further, Tcr abundances that were detected in the wet season months ranged between 1.3 × 103 and 2.29 × 104 copies/mL compared with dry season months (ranging between 0.6 and 31.2 copies/mL). Highest transport rates between 1.67 × 1011 and 1.16 × 1012 copies/s were observed in November 2005 during periods of high rainfall. The study showed that elevated concentrations of antibiotic resistance genes in the order of 102–104 copies/mL can move through stream networks in an agricultural watershed but seasonal variations strongly influenced specific transport patterns of these genes

Aquatic community response to volcanic eruptions on the Ecuadorian Andean flank: evidence from the palaeoecological record

Aquatic ecosystems in the tropical Andes are under increasing pressure from human modification of the landscape (deforestation and dams) and climatic change (increase of extreme events and 1.5 °C on average temperatures are projected for AD 2100). However, the resilience of these ecosystems to perturbations is poorly understood. Here we use a multi-proxy palaeoecological approach to assess the response of aquatic ecosystems to a major mechanism for natural disturbance, volcanic ash deposition. Specifically, we present data from two Neotropical lakes located on the eastern Andean flank of Ecuador. Laguna Pindo (1°27.132′S–78°04.847′W) is a tectonically formed closed basin surrounded by a dense mid-elevation forest, whereas Laguna Baños (0°19.328′S–78°09.175′W) is a glacially formed lake with an inflow and outflow in high Andean Páramo grasslands. In each lake we examined the dynamics of chironomids and other aquatic and semi-aquatic organisms to explore the effect of thick (> 5 cm) volcanic deposits on the aquatic communities in these two systems with different catchment features. In both lakes past volcanic ash deposition was evident from four large tephras dated to c.850 cal year BP (Pindo), and 4600, 3600 and 1500 cal year BP (Baños). Examination of the chironomid and aquatic assemblages before and after the ash depositions revealed no shift in composition at Pindo, but a major change at Baños occurred after the last event around 1500 cal year BP. Chironomids at Baños changed from an assemblage dominated by Pseudochironomus and Polypedilum nubifer-type to Cricotopus/Paratrichocladius type-II, and such a dominance lasted for approximately 380 years. We suggest that, despite potential changes in the water chemistry, the major effect on the chironomid community resulted from the thickness of the tephra being deposited, which acted to shallow the water body beyond a depth threshold. Changes in the aquatic flora and fauna at the base of the trophic chain can promote cascade effects that may deteriorate the ecosystem, especially when already influenced by human activities, such as deforestation and dams, which is frequent in the high Andes

Late Ediacaran occurrences of the organic-walled microfossils Granomarginata and flask-shaped Lagoenaforma collaris gen. et sp. nov.

New occurrences of flask-shaped and envelope-bearing microfossils, including the predominantly Cambrian taxon Granomarginata, are reported from new localities, as well as from earlier in time (Ediacaran) than previously known. The stratigraphic range of Granomarginata extends into the Cambrian System, where it had a cosmopolitan distribution. This newly reported Ediacaran record includes areas from Norway (Baltica), Newfoundland (Avalonia) and Namibia (adjacent to the Kalahari Craton), and puts the oldest global occurrence of Granomarginata in the Indreelva Member (< 563 Ma) of the Stáhpogieddi Formation on the Digermulen Peninsula, Arctic Norway. Although Granomarginata is rare within the assemblage, these new occurrences together with previously reported occurrences from India and Poland, suggest a potentially widespread palaeogeographic distribution of Granomarginata through the middle–late Ediacaran interval. A new flask-shaped microfossil Lagoenaforma collaris gen. et sp. nov. is also reported in horizons containing Granomarginata from the Stáhpogieddi Formation in Norway and the Dabis Formation in Namibia, and flask-shaped fossils are also found in the Gibbett Hill Formation in Newfoundland. The Granomarginata–Lagoenaforma association, in addition to a low-diversity organic-walled microfossil assemblage, occurs in the strata postdating the Shuram carbon isotope excursion, and may eventually be of use in terminal Ediacaran biostratigraphy. These older occurrences of Granomarginata add to a growing record of body fossil taxa spanning the Ediacaran–Cambrian boundary

Women's psychological experiences of physiological childbirth: a meta-synthesis

Objective: To synthesise qualitative studies on women's psychological experiences of physiological childbirth. Design: Meta-synthesis. Methods: Studies exploring women's psychological experiences of physiological birth using qualitative methods were eligible. The research group searched the following databases: MEDLINE, CINAHL, PsycINFO, PsycARTICLES, SocINDEX and Psychology and Behavioural Sciences Collection. We contacted the key authors searched reference lists of the collected articles. Quality assessment was done independently using the Critical Appraisal Skills Programme (CASP) checklist. Studies were synthesised using techniques of meta-ethnography. Results: Eight studies involving 94 women were included. Three third order interpretations were identified: 'maintaining self-confidence in early labour', 'withdrawing within as labour intensifies' and 'the uniqueness of the birth experience'. Using the first, second and third order interpretations, a line of argument developed that demonstrated 'the empowering journey of giving birth' encompassing the various emotions, thoughts and behaviours that women experience during birth. Conclusion: Giving birth physiologically is an intense and transformative psychological experience that generates a sense of empowerment. The benefits of this process can be maximised through physical, emotional and social support for women, enhancing their belief in their ability to birth and not disturbing physiology unless it is necessary. Healthcare professionals need to take cognisance of the empowering effects of the psychological experience of physiological childbirth. Further research to validate the results from this study is necessary. PROSPERO registration number CRD4201603707