Factores que afectan la cobertura del programa de tuberculosis en el primer nivel de atención en Honduras

Introduction:

There is a global consensus that early diagnosis and treatment of tuberculosis (TB) can accelerate its control and mitigate its consequences. The gradual increase in the TB mortality rate from 2014 to 2018 in Honduras, the reform of the health system in 2014, and the partial implementation of the “End TB” strategy motivated this study.

Objective:

To analyze barriers to and facilitators of diagnosis and treatment affecting the national TB program coverage using data from 2015 to 2019 and provide tools for the effective implementation of the “End TB” strategy in San Pedro Sula, Honduras.

Materials and methods:

This was an explanatory sequential mixed-methods study on smear-positive pulmonary TB patients older than 18 years of age. TB notification sheets and medical records from two primary health care facilities were reviewed. Semistructured interviews were conducted with health care providers, patients, and their families.

Results:

A total of 74.6% of the cases (297/398) did not receive a timely diagnosis; 62.3% (185/297) were men, 80.8% (240/297) were adults, 53.7% (108/297) had less than high school education, 49.2% (123/297) had some occupation, and 98.2% of participants received timely treatment. Identified barriers included low socioeconomic conditions, lack of coordination between public and private health systems, and boundaries set by gangs. Identified facilitators included good care and attitude of the health care personnel and the availability of medications.

Conclusions:

The lack of opportunity to diagnose the disease affected the coverage of the national TB program due to cultural and health care barriers.     

A single molecule assay for measuring site-specific DNA cleavage

Sequence-specific DNA cleavage is a key step in a number of genomic transactions. Here, we report a single-molecule technique that allows the simultaneous measurement of hundreds of DNAs, thereby collecting significant statistics in a single experiment. Microbeads are tethered with single DNA molecules in a microfluidic channel. After the DNA cleavage reaction is initiated, the time of cleavage of each DNA is recorded using video microscopy. We demonstrate the utility of our method by measuring the cleavage kinetics of NdeI, a type II restriction endonuclease.     

Using human case studies to teach evolution in high school A.P. biology classrooms

Background

While recent research indicates that using human examples can be an engaging way to teach core evolutionary concepts such as natural selection and phylogenetic thinking, teachers still face potential conflicts and challenges that arise from cultural barriers to teaching and learning about evolution. The “Teaching Evolution through Human Examples” (TEtHE) project developed (1) a set of four curriculum mini-units for advanced placement (A.P.) biology that use human examples to teach evolutionary principles (Adaptation to Altitude, Evolution of Human Skin Color, Malaria, and What Does It Mean To Be Human?), and (2) a cultural and religious sensitivity (CRS) teaching strategies resource that includes background materials and two in-class activities to help teachers create a classroom environment to increase student willingness to engage the topic.

Methods

This paper reports on the development and field test of the TEtHE materials in A.P. biology classes in 10 schools in 8 states during the 2012–2013 school year using a design-based research framework (cf. Anderson and Shattuck in Educ Res 41:16–25, 2012). We chose A.P. classrooms to study the potential impacts of the materials in a “best case scenario” and analyzed data about understanding and acceptance of evolution from pre-post assessments in the 10 classrooms separately to mitigate potential validity concerns arising from the design (Anderson and Shattuck in Educ Res 41:16–25, 2012; Shadish et al. in Experimental and quasi-experimental designs for generalized causal inference. Houghton Mifflin, Boston, 2002). These data were treated as a secondary source of formative data to add additional perspective to teacher self-reports, observations, student and teacher questionnaires, teacher interviews, and student focus groups.

Results

Results indicate that the use of the three curriculum mini-units which focus on natural selection and the CRS classroom activities generally increased A.P. biology students’ understanding and acceptance of evolution. Students whose teachers used one of the CRS activities showed generally larger increases in understanding of evolution than those whose teachers did not use one of the CRS activities.

Conclusions

Although the utility of using human examples to teach evolution in college-level classes has been demonstrated in a few previous studies, this is the first national project of which we are aware to systematically explore the effect of a similar approach in high school biology classes. While we recognize that the results may be mitigated by the limitations of design-based research, particularly the absence of a comparison or control group, the general effectiveness of this approach suggested by qualitative and quantitative data in increasing student understanding and acceptance of evolution suggests that using human examples and explicitly creating a classroom environment to help students engage the topic of evolution are worth considering for further development and more robust testing.

     

Discovery of novel aminoquinazolin-7-yl 6,7-dihydro-indol-4-ones as potent, selective inhibitors of heat shock protein 90

A novel class of Hsp90 inhibitors, structurally distinct from previously reported scaffolds, was developed from rational design and optimization of a compound library screen hit. These aminoquinazoline derivatives, represented by compound 15 (SNX-6833) or 1-(2-amino-4-methylquinazolin-7-yl)-3,6,6-trimethyl-6,7-dihydro-1H-indol-4(5H)-one, selectively bind to Hsp90 and inhibit its cellular activities at concentrations as low as single digit nanomolar.     

How the apple escaped cultivation in North America

Domesticated plants have been transported around the globe through their association with humans and have undergone changes in response to their new environments. In many regions, farmers and, later, plant breeders have developed local landraces to deal with the new conditions or to satisfy the culinary needs of consumers, showing the versatility of these plants and the ingenuity of plant breeders, both ancient and modern. However, in some cases, plants leave behind their human associations and become feral in either the crop fields or natural landscape of the new region. The evolution of ferality has been studied in some crop systems, with many advances made in our understanding of annual crop ferality (e.g., Burger, Lee, & Ellstrand, 2006; Hegde et al., 2006). In contrast, very little is known about the genetics of feral perennial crops, and the study by Cronin, Kron, and Husband (2020) in this issue of Molecular Ecology sheds new light on this type of evolution, revealing the remarkable ability of domesticated apple (Malus domestica) to thrive and reproduce in North America without genetic input from local species.     

Arp2/3 complex inhibition radically alters lamellipodial actin architecture,suspended cell shape,and the cell spreading process

Recent studies have investigated the dendritic actin cytoskeleton of the cell edge''s lamellipodial (LP) region by experimentally decreasing the activity of the actin filament nucleator and branch former, the Arp2/3 complex. Here we extend these studies via pharmacological inhibition of the Arp2/3 complex in sea urchin coelomocytes, cells that possess an unusually broad LP region and display correspondingly exaggerated centripetal flow. Using light and electron microscopy, we demonstrate that Arp2/3 complex inhibition via the drug CK666 dramatically altered LP actin architecture, slowed centripetal flow, drove a lamellipodial-to-filopodial shape change in suspended cells, and induced a novel actin structural organization during cell spreading. A general feature of the CK666 phenotype in coelomocytes was transverse actin arcs, and arc generation was arrested by a formin inhibitor. We also demonstrate that CK666 treatment produces actin arcs in other cells with broad LP regions, namely fish keratocytes and Drosophila S2 cells. We hypothesize that the actin arcs made visible by Arp2/3 complex inhibition in coelomocytes may represent an exaggerated manifestation of the elongate mother filaments that could possibly serve as the scaffold for the production of the dendritic actin network.     

B1 Cell IgE Impedes Mast Cell-Mediated Enhancement of Parasite Expulsion through B2 IgE Blockade

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New evidence for hominin carcass processing strategies at 1.5 Ma, Koobi Fora, Kenya

Reconstruction of early Pleistocene hominin carcass acquisition and processing behaviors are necessarily based at least in part on butchered fossil bones. This paper provides zooarchaeological and taphonomic analyses and behavioral interpretations of three approximately 1.5 million-year-old archaeofaunas from areas 1A and 103 in the Okote Member of the Koobi Fora Formation, northern Kenya: FwJj14A, FwJj14B, and GaJi14. These sites are all located in similar paleoenvironmental contexts, near shallow water with swampy, seasonally flooded areas, and some evidence for more wooded or gallery forest settings. Both individual specimen--and assemblage-level analyses of butchery-marked bones indicate that the hominins appear to have practiced similar butchery strategies at all of these sites, with butchery (defleshing, disarticulation, and marrow extraction) of both high- and low-ranked skeletal elements with no apparent preference for prey size, skeletal region, limb class, or limb portion. Only four tooth-marked specimens, including one likely crocodile-tooth-marked bone, are preserved in all three archaeofaunas. A paucity of limb epiphyses suggests that bone-crunching hyenids may have deleted these portions subsequent to hominin butchery. Strangely, there are no stone tools preserved with the 292 cut-marked and 27 percussion-marked faunal specimens (out of a total of 6,039 specimens), suggesting that raw material availability may have conditioned hominin lithic discard patterns at these locales. These assemblages increase our knowledge of the dietary behavior and ecology of Homo erectus, and provide support for variability in early Pleistocene hominin carcass foraging patterns.