Incidence of cutaneous graft-versus-host disease in a Singapore academic medical centre - A retrospective cohort study.

BACKGROUND: Cutaneous graft-versus-host disease (GVHD) is common in allogeneic haematopoietic stem cell transplantation. HLA mismatch is the most significant determinant of GVHD. Our study aimed to compare the incidence of cutaneous GVHD haploidentical (Haplo) and matched donors in an Asian population. METHODS: Retrospective cohort study of the 2015-2019 bone marrow transplant registry was conducted in a transplant centre. We compared the incidence of cutaneous GVHD in Haplo with allogeneic matched unrelated donor (MUD) and matched-sibling donor (MSD) transplant recipients. Secondary objectives include acute and chronic GVHD incidence, dermatology referrals, and histological findings. RESULTS: One hundred and seventy-nine out of 203 cases were reviewed; 17 (9.5%) Haplo, 80 (44.7%) MUDs and 82 (45.8%) MSDs. The median follow-up for Haplo, MUD and MSD was 15.2, 34.2 and 35.7 months, respectively. Haplo had a higher cumulative incidence of cutaneous GVHD than MUD and MSD (p = 0.053). Chronic GVHD was only reported in MSD. The most common histology was vacuolar interface changes (13 [44.8%]) with a wide range of onset post-transplant (19-456 days). CONCLUSIONS: Haplo donors may have a higher GVHD incidence than MUD and MSD in our predominantly Asian cohort. This information may be helpful when counselling patients pre-transplant. Further prospective studies are required.

Rituximab in Subepidermal Blistering Diseases.

BACKGROUND: Although rituximab is known to be effective in the treatment of pemphigus, its role in subepidermal autoimmune blistering diseases is unclear and currently limited to off-label use. SUMMARY: This is a meta-analysis of case reports, case series, and retrospective studies on the effectiveness and safety of rituximab in bullous pemphigoid, mucous membrane pemphigoid, ocular pemphigoid, and epidermolysis bullosa acquisita. We compared remission and relapse rates in patients who received rituximab with those who only received conventional medical therapy. Comparisons were also made among disease subgroups. KEY MESSAGE: The present analysis suggests that patients with subepidermal autoimmune blistering diseases treated with rituximab achieve a higher rate of complete remission and encounter their first relapse after a longer time interval. However, time to remission and total relapse rates were similar between groups. Adverse events and mortality rates were no more common in patients who received rituximab. This analysis was limited by the absence of randomized controlled trials and the observation that rituximab was used as a late rescue therapy in most reports. In conclusion, rituximab may be effective in subepidermal blistering disease, but randomized controlled studies are required for the validation of current observational data.

Evaluation of Nailfold Capillaroscopy Online Training Using the Fast Track Algorithm.

OBJECTIVE: Nailfold capillaroscopy (NFC) is increasingly used in the early identification of systemic sclerosis (SSc)-related disorders. A consensus "Fast Track algorithm" was developed by the European Alliance of Associations for Rheumatology to aid differentiation of scleroderma from nonscleroderma pattern on NFC. Our objective was to evaluate the online training of NFC using the Fast Track algorithm in the assessment of scleroderma vs nonscleroderma NFC pattern. METHODS: Participants attended the NFC online training workshop and were taught the Fast Track algorithm. Following the training, participants independently evaluated 45 NFC images in the same session, and then 2 to 4 weeks later, through the online platform. Participants had to differentiate between scleroderma vs nonscleroderma pattern, and additionally nonscleroderma pattern (normal) vs nonscleroderma pattern (nonspecific). The inter- and intrarater Cohen [Formula: see text] agreement was calculated. RESULTS: Ninety-eight participants took part in the baseline evaluation, and 61 in the reevaluation session. For identification of scleroderma vs nonscleroderma pattern, the mean (95% CI) inter- and intrarater [Formula: see text] were 0.86 (0.83-0.88) and 0.83 (0.79-0.87), respectively. The overall inter- and intrarater [Formula: see text] in the identification of scleroderma, nonscleroderma (normal), and nonscleroderma (nonspecific) patterns were 0.71 (0.69-0.74) and 0.71 (0.67-0.75), respectively. For nonscleroderma (normal) vs nonscleroderma (nonspecific) pattern, the inter- and intrarater [Formula: see text] were 0.59 (0.55-0.63) and 0.59 (0.54-0.65), respectively. CONCLUSION: In this first study evaluating NFC online training using the Fast Track algorithm, we showed very good inter- and intrarater agreement for the identification of scleroderma and nonscleroderma NFC pattern, supporting the feasibility of online NFC standardized training workshops.

Enlarged postauricular nodules in a young South Asian man.

We report a 19-year-old South Asian man with progressively enlarging postauricular nodules over a 5-year period, which were eventually treated by surgical resection.

Efficacy of Ivermectin Treatment on Disease Progression Among Adults With Mild to Moderate COVID-19 and Comorbidities: The I-TECH Randomized Clinical Trial.

Importance: Ivermectin, an inexpensive and widely available antiparasitic drug, is prescribed to treat COVID-19. Evidence-based data to recommend either for or against the use of ivermectin are needed. Objective: To determine the efficacy of ivermectin in preventing progression to severe disease among high-risk patients with COVID-19. Design, Setting, and Participants: The Ivermectin Treatment Efficacy in COVID-19 High-Risk Patients (I-TECH) study was an open-label randomized clinical trial conducted at 20 public hospitals and a COVID-19 quarantine center in Malaysia between May 31 and October 25, 2021. Within the first week of patients' symptom onset, the study enrolled patients 50 years and older with laboratory-confirmed COVID-19, comorbidities, and mild to moderate disease. Interventions: Patients were randomized in a 1:1 ratio to receive either oral ivermectin, 0.4 mg/kg body weight daily for 5 days, plus standard of care (n = 241) or standard of care alone (n = 249). The standard of care consisted of symptomatic therapy and monitoring for signs of early deterioration based on clinical findings, laboratory test results, and chest imaging. Main Outcomes and Measures: The primary outcome was the proportion of patients who progressed to severe disease, defined as the hypoxic stage requiring supplemental oxygen to maintain pulse oximetry oxygen saturation of 95% or higher. Secondary outcomes of the trial included the rates of mechanical ventilation, intensive care unit admission, 28-day in-hospital mortality, and adverse events. Results: Among 490 patients included in the primary analysis (mean [SD] age, 62.5 [8.7] years; 267 women [54.5%]), 52 of 241 patients (21.6%) in the ivermectin group and 43 of 249 patients (17.3%) in the control group progressed to severe disease (relative risk [RR], 1.25; 95% CI, 0.87-1.80; P = .25). For all prespecified secondary outcomes, there were no significant differences between groups. Mechanical ventilation occurred in 4 (1.7%) vs 10 (4.0%) (RR, 0.41; 95% CI, 0.13-1.30; P = .17), intensive care unit admission in 6 (2.4%) vs 8 (3.2%) (RR, 0.78; 95% CI, 0.27-2.20; P = .79), and 28-day in-hospital death in 3 (1.2%) vs 10 (4.0%) (RR, 0.31; 95% CI, 0.09-1.11; P = .09). The most common adverse event reported was diarrhea (14 [5.8%] in the ivermectin group and 4 [1.6%] in the control group). Conclusions and Relevance: In this randomized clinical trial of high-risk patients with mild to moderate COVID-19, ivermectin treatment during early illness did not prevent progression to severe disease. The study findings do not support the use of ivermectin for patients with COVID-19. Trial Registration: ClinicalTrials.gov Identifier: NCT04920942.

Acne agminata: dermoscopic features and a short review.

Acne agminata is a rare idiopathic inflammatory dermatosis. Treatment is variable with no clear consensus. We herein report a case of a 31-year-old man with sudden onset papulonodular eruptions on his face over two months. Histopathological examination revealed superficial granuloma composed of epithelioid histiocytes and scattered multinucleated giant cells, confirming acne agminata. Dermoscopy showed focal orangish structureless areas with follicular openings with white keratotic plugs. He achieved complete clinical resolution with oral prednisolone in 6 weeks. We also reviewed the literature regarding the reported treatment regimens used.

Population genomics reveals variable patterns of immune gene evolution in monarch butterflies (Danaus plexippus).

Humoral and cellular immune responses provide animals with major defences against harmful pathogens. While it is often assumed that immune genes undergo rapid diversifying selection, this assumption has not been tested in many species. Moreover, it is likely that different classes of immune genes experience different levels of evolutionary constraint, resulting in varying selection patterns. We examined the evolutionary patterns for a set of 91 canonical immune genes of North American monarch butterflies (Danaus plexippus), using as an outgroup the closely related soldier butterfly (Danaus eresimus). As a comparison to these immune genes, we selected a set of control genes that were paired with each immune for approximate size and genomic location. As a whole, these immune genes had a significant but modest reduction in Tajima's D relative to paired-control genes, but otherwise did not show distinct patterns of population genetic variation or evolutionary rates. When further partitioning these immune genes into four functional classes (recognition, signalling, modulation, and effector), we found distinct differences among these groups. Relative to control genes, recognition genes exhibit increased nonsynonymous diversity and divergence, suggesting reduced constraints on evolution, and supporting the notion that coevolution with pathogens results in diversifying selection. In contrast, signalling genes showed an opposite pattern of reduced diversity and divergence, suggesting evolutionary constraints and conservation. Modulator and effector genes showed no statistical differences from controls. These results are consistent with patterns found in immune genes in fruit flies and Pieris butterflies, suggesting that consistent selective pressures on different classes of immune genes broadly govern the evolution of innate immunity among insects.

[Effects of Different Land Use Practices on Nitrogen Loss from Runoff During Rainfall Events].

To understand the effect of nitrogen from runoff during rainfall events for different land uses, sub-catchments A and B in the small Shipanqiu watershed in Zhong County, Chongqing-which were managed using different land use practices-were taken as research objects. Runoff flow and nitrogen levels at the outlet of the catchment were monitored. Sub-catchment A is an agroforestry-water complex and sub-catchment B is the site of traditional agriculture. EMC was used to evaluate the average concentration of runoff nitrogen during rainfall events, and the effect of this runoff nitrogen on the small watershed with different land use systems was analyzed. The results showed that the TN concentration in catchment B (1.37-15.17 mg·L-1) > catchment A (0.84-9.28 mg·L-1); the ratio of the first peak to the second peak in catchment A was 62%, which was far less than the 97% in catchment B; the average DN/TN values were 69% and 75% in catchments A and B, respectively; and the average NN/DN values were 67% and 80% in catchments A and B, respectively. The different land use practices have significant impacts on nitrogen loss. Compared with the catchment where traditional agricultural practices were followed, the agroforestry-water complex catchment effectively reduced the loss of nitrogen and decreased the first TN peak value and DN/TN and NN/DN values. This study provides a scientific basis for the prevention and control of non-point source pollution in small watersheds in the area of the Three Gorges Reservoir.

Transcriptomics of monarch butterflies (Danaus plexippus) reveals that toxic host plants alter expression of detoxification genes and down-regulate a small number of immune genes.

Herbivorous insects have evolved many mechanisms to overcome plant chemical defences, including detoxification and sequestration. Herbivores may also use toxic plants to reduce parasite infection. Plant toxins could directly interfere with parasites or could enhance endogenous immunity. Alternatively, plant toxins could favour down-regulation of endogenous immunity by providing an alternative (exogenous) defence against parasitism. However, studies on genomewide transcriptomic responses to plant defences and the interplay between plant toxicity and parasite infection remain rare. Monarch butterflies (Danaus plexippus) are specialist herbivores of milkweeds (Asclepias spp.), which contain toxic cardenolides. Monarchs have adapted to cardenolides through multiple resistance mechanisms and can sequester cardenolides to defend against bird predators. In addition, high-cardenolide milkweeds confer monarch resistance to a specialist protozoan parasite (Ophryocystis elektroscirrha). We used this system to study the interplay between the effects of plant toxicity and parasite infection on global gene expression. We compared transcriptional profiles between parasite-infected and uninfected monarch larvae reared on two milkweed species. Our results demonstrate that monarch differentially express several hundred genes when feeding on A. curassavica and A. incarnata, two species that differ substantially in cardenolide concentrations. These differentially expressed genes include genes within multiple families of canonical insect detoxification genes, suggesting that they play a role in monarch toxin resistance and sequestration. Interestingly, we found little transcriptional response to infection. However, parasite growth was reduced in monarchs reared on A. curassavica, and in these monarchs, several immune genes were down-regulated, consistent with the hypothesis that medicinal plants can reduce reliance on endogenous immunity.

How symbiosis and ecological context influence the variable expression of transgenerational wing induction upon fungal infection of aphids.

Aphids, like most animals, mount a diverse set of defenses against pathogens. For aphids, two of the best studied defenses are symbiont-conferred protection and transgenerational wing induction. Aphids can harbor bacterial symbionts that provide protection against pathogens, parasitoids and predators, as well as against other environmental stressors. In response to signals of danger, aphids also protect not themselves but their offspring by producing more winged than unwinged offspring as a way to ensure that their progeny may be able to escape deteriorating conditions. Such transgenerational wing induction has been studied most commonly as a response to overcrowding of host plants and presence of predators, but recent evidence suggests that pea aphids (Acyrthosiphon pisum) may also begin to produce a greater proportion of winged offspring when infected with fungal pathogens. Here, we explore this phenomenon further by asking how protective symbionts, pathogen dosage and environmental conditions influence this response. Overall, while we find some evidence that protective symbionts can modulate transgenerational wing induction in response to fungal pathogens, we observe that transgenerational wing induction in response to fungal infection is highly variable. That variability cannot be explained entirely by symbiont association, by pathogen load or by environmental stress, leaving the possibility that a complex interplay of genotypic and environmental factors may together influence this trait.

The Effects of Milkweed Induced Defense on Parasite Resistance in Monarch Butterflies, Danaus plexippus.

Many plants express induced defenses against herbivores through increasing the production of toxic secondary chemicals following damage. Phytochemical induction can directly or indirectly affect other organisms within the community. In tri-trophic systems, increased concentrations of plant toxins could be detrimental to plants if herbivores can sequester these toxins as protective chemicals for themselves. Thus, through trophic interactions, induction can lead to either positive or negative effects on plant fitness. We examined the effects of milkweed (Asclepias spp.) induced defenses on the resistance of monarch caterpillars (Danaus plexippus) to a protozoan parasite (Ophryocystis elektroscirrha). Milkweeds contain toxic secondary chemicals called cardenolides, higher concentrations of which are associated with reduced parasite growth. Previous work showed that declines in foliar cardenolides caused by aphid attack render monarch caterpillars more susceptible to infection. Here, we ask whether cardenolide induction by monarchs increases monarch resistance to disease. We subjected the high-cardenolide milkweed A. curassavica and the low-cardenolide A. syriaca to caterpillar grazing, and reared infected and uninfected caterpillars on these plants. As expected, monarchs suffered less parasite growth and disease when reared on A. curassavica than on A. syriaca. We also found that herbivory increased cardenolide concentrations in A. curassavica, but not A. syriaca. However, cardenolide induction in A. curassavica was insufficient to influence monarch resistance to the parasite. Our results suggest that interspecific variation in cardenolide concentration is a more important driver of parasite defense than plasticity via induced defenses in this tri-trophic system.

Restoration of an endangered plant, Hygrophila pogonocalyx, leads to an adaptive host shift of the chocolate pansy (Junonia iphita iphita).

Anthropogenic introduction of a plant species may cause novel encounters between the plant and local herbivores, and initiate evolutionary changes in host plant usage by herbivores. Until recently the endemic aquatic plant Hygrophila pogonocalyx was endangered and had a restricted distribution in Taiwan. Massive restoration efforts since 1997 have led to an expansion of the plant's distribution and a novel encounter between it and an Asian butterfly, the chocolate pansy, Junonia iphita (Nymphalidae). This butterfly appears to have colonized H. pogonocalyx, switching from its original host, Strobilanthes penstemonoides var. formosana. In the present study, we aimed to investigate whether the utilization of H. pogonocalyx as a host plant has initiated a differentiation between butterflies using the novel and the original hosts. To this purpose we collected butterflies from patches of the two host plants which grow sympatrically. We tested oviposition preference for the two hosts and larval performance on them. Female adults exhibited distinct oviposition preference toward the host plant their mothers preferred. Offspring showed greater survivorship and pupal weight when fed on the host plant their mothers preferred. Male adults displayed territorial behaviors on the host plant that their mothers had preferred. Finally, the survival rate of offspring produced from cross-mating between individuals with different host plant preference was lower than that of non-hybrids. Taken together, we suggest that genetic differentiation has occurred between individuals preferring H. pogonocalyx versus S. penstemonoides as host plants via host shifting. This process was likely induced by the mass restoration of the formerly rare and endangered plant species.