Knowledge, attitudes and practices towards yaws in endemic areas of Ghana, Cameroon and Côte d'Ivoire.

Yaws, caused by Treponema pallidum ssp. pertenue, remains a significant public health concern in tropical regions of West Africa and the South Pacific, primarily affecting children in remote areas with limited access to hygiene and sanitation. In this study, conducted in three endemic countries of West Africa where yaws remains a significant public health concern (Ghana, Cameroon, and Côte d'Ivoire), we aimed to assess the knowledge, attitudes, and practices related to yaws among community members, community health workers (CHWs), and traditional healers. The study revealed variations in the perception of causes of yaws among community members: the majority or participants in Ghana attributed yaws to germs (60.2%); in Cameroon the most reported form of transmission was contact with or drinking infected water sources (44.6%); and in Côte d'Ivoire both of these answers were also the most prevalent (60.3% germs and 93.% water sources). A substantial proportion of participants in Côte d'Ivoire also associated yaws with witchcraft and divine punishment (44.8%). Only a small proportion of individuals in Ghana and Côte d'Ivoire correctly identified contact with an infected person as a form of transmission (11.9% and 20.7%, respectively) and less than half in Cameroon (42.6%), although more than 98% of all participants reported avoidance behaviours towards yaws infected people due to fear of getting infected. Most participants expressed a preference for seeking care at hospitals (49.2%, 60.6%, 86.2%) or health care professionals including doctors and nurses (58.5%, 41,5% and 17.2%) if they were diagnosed with yaws, although a quarter of participants in Côte d'Ivoire also sought support from traditional healers. The CHWs interviewed were generally well-trained on yaws causes and treatment options, although they often reported low availability of treatment and diagnostic tests for yaws. Our findings underscore the need for community education, awareness campaigns, ongoing CHW training, and improved access to yaws treatment and diagnostic resources. The data also suggest that collaboration with traditional healers, who usually hold a highly esteemed position in the society, such as giving training on yaws causes and transmission or exchanging knowledge on treatment options, could be beneficial in certain regions, particularly in Côte d'Ivoire.

LAMP4yaws: Treponema pallidum, Haemophilus ducreyi loop mediated isothermal amplification - protocol for a cross-sectional, observational, diagnostic accuracy study.

INTRODUCTION: Yaws, caused by the bacterium Treponema pallidum subsp. pertenue, is a neglected tropical disease targeted for eradication by 2030. Improved diagnostics will be essential to meet this goal. Diagnosis of yaws has relied heavily on clinical and serological tools. However, the presence of coendemic cutaneous skin ulcer diseases, such as lesions caused by Haemophilus ducreyi (HD), means these techniques do not provide a reliable diagnosis. Thus, new diagnostic tools are needed. Molecular tools such as PCR are ideal, but often expensive as they require trained technicians and laboratory facilities, which are often not available to national yaws programmes. METHODS AND ANALYSIS: The LAMP4yaws project is a cross-sectional, observational, diagnostic accuracy study of a combined Treponema pallidum (TP) and HD loop mediated isothermal amplification (TPHD-LAMP) test performed under real world conditions in three endemic countries in West Africa. Individuals with serologically confirmed yaws will be recruited in Cameroon, Côte d'Ivoire and Ghana. Each participant will provide paired swabs, one of which will be sent to the respective national reference laboratory for yaws quantitative PCR and the other will be tested for both TP and HD using the TPHD-LAMP test at local district laboratories. Sensitivity and specificity of the TPHD-LAMP test will be calculated against the reference standard qPCR. We will also assess the acceptability, feasibility and cost-effectiveness of the test. We anticipate that results from this study will support the adoption of the TPHD-LAMP test for use in global yaws eradication efforts. ETHICS AND DISSEMINATION: We have received ethical approval from all relevant institutional and national ethical committees. All participants, or their parents or guardians, must provide written informed consent prior to study enrolment. Study results will be published in an open access journal and disseminated with partners and the World Health Organization. TRIAL REGISTRATION NUMBER: NCT04753788.

High Dynamic Range Digital Assay Enabled by Dual-Volume Centrifugal Step Emulsification.

We implement dual-volume centrifugal step emulsification on a single chip to extend the dynamic range of digital assays. Compared to published single-volume approaches, the range between the lower detection limit (LDL) and the upper limit of quantification (ULQ) increases by two orders of magnitude. In comparison to existing multivolume approaches, the dual-volume centrifugal step emulsification requires neither complex manufacturing nor specialized equipment. Sample metering into two subvolumes, droplet generation, and alignment of the droplets in two separate monolayers are performed automatically by microfluidic design. Digital quantification is demonstrated by exemplary droplet digital loop-mediated isothermal amplification (ddLAMP). Within 5 min, the reaction mix is split into subvolumes of 10.5 and 2.5 µL, and 2,5k and 176k droplets are generated with diameters of 31.6 ± 1.4 and 213.9 ± 7.5 µm, respectively. After 30 min of incubation, quantification over 5 log steps is demonstrated with a linearity of R2 ≥ 0.992.

Short-term regulation of the hypothalamic melanocortinergic system under fasting and defined glucose-refeeding conditions in rats: a laser capture microdissection (LMD)-based study.

It is well established that under fasting conditions the expression of the orexigenic neuropeptide agouti-related peptide (AGRP) is up-regulated in the hypothalamic arcuate nucleus (ARC), while inconsistent data exist regarding fasting regulation of the anorexigenic neurohormone proopiomelanocortin (POMC). Inconsistencies might have methodological reasons, especially concerning neuromorphological and/or experimental (nutritional) specificity. We analyzed the expression of both neuropeptides in ARC neurons, using lasercapture microdissection (LMD) and real-time PCR in 12h fasted vs. fed Wistar rats as well as after a standardized glucose load, i.e., under clinically relevant conditions in terms of diagnosing glucose intolerance in the human. Under fasting conditions, clear up-regulation of AGRP was observed, with increasing magnitude in ARC single neurons (SNP) as compared to ARC cell layers (+125% vs. +23%, resp.), closely correlated to hypoinsulinemia and hypoleptinemia. Surprisingly, in the fasting state POMC was not found to be down-regulated, neither in ARC cell layers nor in ARC single neurons (+9% vs. +6%). However, glucose-refeeding under diagnostically relevant conditions led to strong neuronal up-regulation of POMC expression in ARC SNP (+128%), and AGRP down-regulation (-50%). In conclusion, experimentally, topographically, and analytically specific and standardized conditions confirmed AGRP in ARC neurons as being neuronally up- and down-regulated, resp., depending on the general nutritional state, while POMC was found to be (up-) regulated only after peripheral glucose load. Findings suggest that POMC in ARC neurons acts glucose-mediated as an "anti-orexigenic" neurohormone, specifically responding to hyperglycemia.