Deep palmar phenotyping in atopic eczema: patterns associated with Filaggrin variants, disease severity and barrier function in a South Asian population

BACKGROUND

Hyperlinear palms are described as a feature of loss-of-function (LoF) variants in Filaggrin (FLG).

OBJECTIVE

To explore the phenotype of participants (age <31 years) with atopic eczema of Bangladeshi ancestry from East London and investigate which factors best associate with LoF FLG variants.

METHODS

A cross-sectional study with participants recruited between May 2018 and March 2020. Patterns of palmar linearity were categorised and modelled with Eczema Area and Severity Index (EASI), transepidermal water loss (TEWL), skin hydration (SH) and LoF FLG variants.

RESULTS

Five hundred and six complete cases were available. Five palm patterns were noted. The 'prominent diamond' pattern associated best with EASI (marginal effects [ME], 2.53, 95% CI 1.74-3.67), TEWL (ME 1.32, 95% CI 1.11-1.62) and SH (ME 0.85, 95% CI 0.78-0.96). Using five palm patterns had some ability to discriminate LoF FLG variants (area under the receiver operator characteristic [AUROC] 76.07; 95% CI 71.58-80.57), improving in subgroup analysis with only fine perpendicular/prominent diamond patterns and SH (AUROC 89.11%; 95% CI 84.02-94.19).

LIMITATIONS

Single centre study design with humans classifying clinical patterns. Stability of temperature and humidity not guaranteed across TEWL and SH measurements despite using a climate controlled room.

CONCLUSION

Palm patterns associate with EASI and TEWL. The fine perpendicular/prominent diamond patterns are markers to detect absence/presence of LoF FLG variants respectively.

Health Problems of Bangladeshi Tannery Workers

Tanners are exposed to raw hides as well as to various toxic chemicals. The study was intended to find out the health problems among tannery workers. This descriptive cross-sectional study was conducted in 2019 among 223 workers working with raw hides and chemicals selected by stratified random sampling in ten tanneries of Leather Industry Area, Hemayetpur, Savar, Dhaka, Bangladesh. Data were collected by the principal investigator after taking informed written consent from the tanners using a pre-tested interview schedule and a check-list. Data were cross-checked for consistency and accuracy. All relevant ethical issues including approval from Institutional Review Board (IRB), and data quality assurance issues were taken into consideration. Analysis of data was carried out by using computer software SPSS version 20.0 with anonymity. Descriptive statistics were used to describe the data, while Chi-square test was carried out to measure statistical association. As many as 97(43.5%) workers were in age group of 15 to 24 years with a mean age of 28.4±9.5 years. An overwhelming majority 204(91.5%) were males, three-fifths 134(60.1%) of the workers were married, while 213(95.5%) tanners had religion Islam. Majority 122(54.7%) tanners had primary level of education, whereas 56(25.1%) had secondary level and 44(19.7%) had no formal schooling. The mean monthly family income was 13744.4±3485.5 Taka. More than three-fourths 170(76.2%) workers had more than four family members with over half 114(51.1%) of the workers were smokers. Of 223, over half 124(55.6%) of the workers were affected with at least one health problem. Majority of the workers suffered from skin diseases (51.6%), musculoskeletal disorders (33.1%), gastrointestinal problems (22.6%), chronic headache (14.5%) and respiratory problems (14.5%). Only 9(4.0%) workers had pre-placement orientation, while 196(66.4%) workers did not notice the necessity for pre-placement training. Of ten tanneries, cent per cent had foul smell, 80.0% each had poor lighting and discomfort temperature, 60.0% had intolerable noise, 50.0% were with poor ventilation system, and only 30.0% had adequate waste management facilities. The tanneries did not have medical facilities even for emergency conditions. Health problems are significantly associated with job duration (p<0.01), working sections (p<0.05) and smoking status (p<0.001) of the workers. The overall environment of the tanneries is far from satisfactory. Skin diseases, musculoskeletal disorders, gastrointestinal problems, chronic headache and respiratory diseases are the common identified health problems. A considerable number of workers are unconcerned for the pre-placement orientation, and do not use Personal Protective Equipments (PPEs). As a rule, Personal Protective Equipments (PPEs) are not made available to workers by the tannery authorities, and lack of treatment facilities of the tanneries is a common place.

Integrins as a drug target in liver fibrosis

As the worldwide prevalence of chronic liver diseases is high and continuing to increase, there is an urgent need for treatment to prevent cirrhosis-related morbidity and mortality. Integrins are heterodimeric cell-surface proteins that are promising targets for therapeutic intervention. αv integrins are central in the development of fibrosis as they activate latent TGFβ, a known profibrogenic cytokine. The αv subunit can form heterodimers with β1, β3, β5, β6 or β8 subunits and one or more of these integrins are central to the development of liver fibrosis, however, their relative importance is not understood. This review summarises the current knowledge of αv integrins and their respective β subunits in different organs, with a focus on liver fibrosis and the emerging preclinical and clinical data with regards to αv integrin inhibitors.

Modeling of Temporal Exposure to the Ambient Environment and Eczema Severity

Atopic eczema is a common and complex disease. Missing genetic hereditability and increasing prevalence in industrializing nations point toward an environmental driver. We investigated the temporal association of weather and pollution parameters with eczema severity. This cross-sectional clinical study was performed between May 2018 and March 2020 and is part of the Tower Hamlets Eczema Assessment. All participants had a diagnosis of eczema, lived in East London, were of Bangladeshi ethnicity, and were aged <31 years. The primary outcome was the probability of having an Eczema Area and Severity Index score > 10 after previous ambient exposure to commonly studied meteorological variables and pollutants. There were 430 participants in the groups with Eczema Area and Severity Index ≤ 10 and 149 in those with Eczema Area and Severity Index > 10. Using logistic generalized additive models and a model selection process, we found that tropospheric ozone averaged over the preceding 270 days was strongly associated with eczema severity alongside the exposure to fine particles with diameters of 2.5 μm or less (fine particulate matter) averaged over the preceding 120 days. In our models and analyses, fine particulate matter appeared to largely act in a supporting role to ozone. We show that long-term exposure to ground-level ozone at high levels has the strongest association with eczema severity.

School formation characteristics and stimuli based modeling of tetra fish

Self-organizing motion is an important yet inadequately understood phenomena in the field of collective behavior. For birds flocks, insect swarms, and fish schools, group behavior can provide a mechanism for defense against predators, better foraging and mating capabilities and increased hydro/aerodynamic efficiency in long-distance migration events. Although collective motion has received much scientific attention, more work is required to model and understand the mechanisms responsible for school initiation and formation, and information transfer within these groups. Here we investigate schooling of black tetra (Gymnocorymbus ternetzi) fish triggered by startle stimuli in the form of approaching objects. High-speed video and tagging techniques were used to track the school and individual members. We then measured several variables including reaction times, group formation shapes, fish velocity, group density, and leadership within the group. These data reveal three things: (1) information propagates through the group as a wave, indicating that each fish is not reacting individually to the stimulus, (2) the time taken for information to transfer across the group is independent of group density, and (3) information propagates across large groups faster than would be expected if the fish were simply responding to the motion of their nearest neighbor. A model was then built wherein simulated fish have a simple 'stimuli/escape' vector based on a hypothetical field of vision. The model was used to simulate a group of individual fish with initial conditions, size, and stimuli similar to the biological experiments. The model revealed similar behavior to the biological experiments and provide insights into the observed patterns, response times, and wave speeds.

How vision governs the collective behaviour of dense cycling pelotons

In densely packed groups demonstrating collective behaviour, such as bird flocks, fish schools or packs of bicycle racers (cycling pelotons), information propagates over a network, with individuals sensing and reacting to stimuli over relatively short space and time scales. What remains elusive is a robust, mechanistic understanding of how sensory system properties affect interactions, information propagation and emergent behaviour. Here, we show through direct observation how the spatio-temporal limits of the human visual sensory system govern local interactions and set the network structure in large, dense collections of cyclists. We found that cyclists align in patterns within a ± 30° arc corresponding to the human near-peripheral visual field, in order to safely accommodate motion perturbations. Furthermore, the group structure changes near the end of the race, suggesting a narrowing of the used field of vision. This change is consistent with established theory in psychology linking increased physical exertion to the decreased field of perception. Our results show how vision, modulated by arousal-dependent neurological effects, sets the local arrangement of cyclists, the mechanisms of interaction and the implicit communication across the group. We furthermore describe information propagation phenomena with an analogous elastic solid mechanics model. We anticipate our mechanistic description will enable a more detailed understanding of the interaction principles for collective behaviour in a variety of animals.

Characterization of monoclonal antibodies with specificity for the core oligosaccharide of Shigella lipopolysaccharide

Monoclonal antibodies (MAbs) were prepared against different strains of Shigella, following immunization of BALB/c mice with a heat-killed preparation of Shigella. Antibody-producing hybridomas were screened in an indirect enzyme-linked immunoadsorbent assay (ELISA) and epitope specificity determined using chemically defined lipopolysaccharide, lipid, and KDO fragments. Five MAbs were characterized and the following specificities identified: 2C32E6 and 4D64B9 (reactive to S. flexneri and S. boydii), 5E45D8 (reactive with S. flexneri), 4B33D10 and 1B52F10 (all species of Shigella). The properties of 1B52F10 revealed its potential importance in immunological detection of Shigella from unknown samples, as it was able to bind to all strains of Shigella.

Evaluation of a standardised procedure to assess the shape of pellets using image analysis

The influence of threshold definition, number of pellets counted, image magnification and lightning technique on the assessment of pellet shape has been investigated using three batches of pellets and an image analysis system. The pellet parameters measured were 'aspect ratio', 'circularity', 'projection sphericity', 'e(R)' and 'Feret diameter.' The methodical error, reproducibility and repeatability of the results were chosen as statistical test parameters. The position of the light source is crucial in providing an accurate particle size value. Top light was identified as the illumination technique that gave a mean pellet size similar to the true pellet size. The use of a light table produced significantly larger pellet size values. A minimum pixel resolution appears necessary for an accurate shape parameter definition. One pixel should not cover more than 30 microm for pellets of an average particle size of 1.2 mm. Shape descriptors, which are based on a multiple combination of area and perimeter data such as the circularity, are greatly dependent on the number of pellets counted. Shape factors, which do not (aspect ratio) or only as a single value do involve an area or perimeter measurement (e(R), projection sphericity) are, however, nearly independent of the number of pellets counted, as long as the magnification is sufficiently large and the pellets are randomly drawn from the batch. For nearly spherical particles, the methodical error is below 1%, but for elongated particles this error can reach 5%. The repeatability is also very good for nearly spherical particles (<2%), but increases to very large values if the particles are clearly elongated. The limiting values for the various shape factors should be reconsidered. An upper value for the aspect ratio of 1.1 and a lower value of 0.6 for e(R) are recommended. The circularity should not be used as the shape factor to characterise spheres, because errors in image recognition can affect strongly the applicability of this shape factor. The projection sphericity has only a limited sensitivity to variations in particle shape.

Treatment for iron deficiency anaemia with a combined supplementation of iron, vitamin A and zinc in women of Dinajpur, Bangladesh

OBJECTIVE

The study was set up to determine to what extent the addition of a supplement of vitamin A alone or in combination with zinc would improve standard iron treatment and correction of iron deficiency anaemia.

DESIGN

216 non-pregnant anaemic women of 15-45 years of age with haemoglobin levels < or = 100 g/l were randomly assigned to three treatment groups. One group (A) received iron alone, a second group (B) received iron and vitamin A, and a third group (C) received iron, vitamin A and zinc. Every woman was given one iron capsule per day for 60 days as FeSO4 containing 60 mg of elemental iron. In addition, groups B and C received 200,000 i.u. of vitamin A, given as a supervised dose, on the first day of the treatment after collection of the blood sample. Group C received one zinc tablet per day for 60 days as zinc gluconate containing 15 mg of elemental zinc.

SETTING

The north-western part of Bangladesh in the urban slums of Dinajpur district between February and August 1995.

SUBJECTS

To select women with a haemoglobin level of < or = 100 g/l, all the women of four randomly selected municipal slums of the district in the targeted age group (328) were invited to take part in the study. Blood samples were analysed for haemoglobin, serum iron, total iron binding capacity (TIBC), ferritin, retinol and zinc.

RESULTS

Out of the 328 women screened, 254 (77.5%) had a haemoglobin level < or = 100 g/l and 322 (98%) < or = 120 g/l. The three treatment schedules significantly increased haemoglobin levels and improved iron parameters, except for serum iron in the group who received iron alone. The group who received iron, vitamin A and zinc responded best with an increase in haemoglobin of 17.9 g/l as compared to the group receiving iron alone (13.4 g/l). Iron and vitamin A treatment gave an intermediate response of 15.9 g/l. However, these differences are only statistically significant only for the group who received iron, vitamin A and zinc and only for the increase in haemoglobin, P = 0.03.

CONCLUSION

The results are suggestive that the addition of vitamin A and zinc to the treatment for anaemia can increase haemoglobin levels more than with iron alone.