Morphological and physiological characteristics of biological soil crusts (BSCs) enhance soil stability and fertility, and influence soil chemistry. However, the effect of BSCs on soil ...physico-chemical properties may vary depending on taxa (cyanobacteria, lichen, bryophytes) and species, and be susceptible to soil surface disturbance. We examined a wide variety of soil physico-chemical properties associated with five BSC components (cyanobacteria crust, one moss species, three lichen species) naturally occurring in the study area, and bare soil along a disturbance gradient in a semiarid grassland ecosystem in Central Mexico. We addressed the following questions: 1) Do different BSC components create distinct soil microsites characterized by a particular combination of physico-chemical properties? 2) Do distinct soil properties change beneath different BSC components? 3) Does grazing disturbance modify or override species-specific BSC effects? We found that BSC components and bare soil generated distinct soil microsites, however, this effect diminished with increasing grazing pressure. Also, most of the soil variables examined differed between BSC components and bare soil along the gradient. While soil properties associated with cyanobacteria were relatively similar compared to bare soil along the gradient, Diploschistes diacapsis and Lecidella sp. showed decreases in pH and marked differences in mineral nutrient concentration (i.e. variations in Na, Fe and Zn concentration respect to other BSC components and bare soil). Grazing intensity and frequency changed species-specific effects of D. diacapsis, specially modifying its effect on soil texture, diminishing its effect on pH, K and Na concentration, and increasing its effect on Ca and Zn concentration. We conclude that BSC components contribute to natural small-scale soil heterogeneity, and that soil disturbance substantially modifies the nature and magnitude of this effect with potentially important implications on ecosystem processes. Because of the potential influence of other factors (i.e. climate, vascular plants, microbial activity) on BSCs' relation to soil properties, this assertion should be tested including these factors and in multiple ecosystems.
•We explored the influence of BSCs on soil physico-chemical properties in a grassland.•We evaluated the impact of grazing intensity on species-specific BSC effects.•BSC species modify single soil properties and create distinct soil microsites.•BSCs greatly contribute to soil heterogeneity at a small scale.•With increasing grazing intensity BSC effects diminish.
Grazing represents one of the most common disturbances in drylands worldwide, affecting both ecosystem structure and functioning. Despite the efforts to understand the nature and magnitude of grazing ...effects on ecosystem components and processes, contrasting results continue to arise. This is particularly remarkable for the biological soil crust (BSC) communities (i.e., cyanobacteria, lichens, and bryophytes), which play an important role in soil dynamics. Here we evaluated simultaneously the effect of grazing impact on BSC communities (resistance) and recovery after livestock exclusion (resilience) in a semiarid grassland of Central Mexico. In particular, we examined BSC species distribution, species richness, taxonomical group cover (i.e., cyanobacteria, lichen, bryophyte), and composition along a disturbance gradient with different grazing regimes (low, medium, high impact) and along a recovery gradient with differently aged livestock exclosures (short-, medium-, long-term exclusion). Differences in grazing impact and time of recovery from grazing both resulted in slight changes in species richness; however, there were pronounced shifts in species composition and group cover. We found we could distinguish four highly diverse and dynamic BSC species groups: (1) species with high resistance and resilience to grazing, (2) species with high resistance but low resilience, (3) species with low resistance but high resilience, and (4) species with low resistance and resilience. While disturbance resulted in a novel diversity configuration, which may profoundly affect ecosystem functioning, we observed that 10 years of disturbance removal did not lead to the ecosystem structure found after 27 years of recovery. These findings are an important contribution to our understanding of BCS dynamics from a species and community perspective placed in a land use change context.
Patients with solid organ transplant (SOT) and solid tumors are usually excluded from clinical trials testing immune checkpoint blockers (ICB). As transplant rates are increasing, we aimed to ...evaluate ICB outcomes in this population, with a special focus on lung cancer.
We conducted a multicenter retrospective cohort study collecting real data of ICB use in patients with SOT and solid tumors. Clinical data and treatment outcomes were assessed by using retrospective medical chart reviews in every participating center. Study endpoints were: overall response rate (ORR), 6-month progression-free survival (PFS), and grade ≥3 immune-related adverse events.
From August 2016 to October 2022, 31 patients with SOT (98% kidney) and solid tumors were identified (36.0% lung cancer, 19.4% melanoma, 13.0% genitourinary cancer, 6.5% gastrointestinal cancer). Programmed death-ligand 1 expression was positive in 29% of tumors. Median age was 61 years, 69% were males, and 71% received ICB as first-line treatment. In the whole cohort the ORR was 45.2%, with a 6-month PFS of 56.8%. In the lung cancer cohort, the ORR was 45.5%, with a 6-month PFS of 32.7%, and median overall survival of 4.6 months. The grade 3 immune-related adverse events rate leading to ICB discontinuation was 12.9%. Allograft rejection rate was 25.8%, and risk of rejection was similar regardless of the type of ICB strategy (monotherapy or combination, 28% versus 33%, P = 1.0) or response to ICB treatment.
ICB could be considered a feasible option for SOT recipients with some advanced solid malignancies and no alternative therapeutic options. Due to the risk of allograft rejection, multidisciplinary teams should be involved before ICB therapy.
•Immune checkpoint blockers may be a treatment strategy in SOT patients with cancer.•One-third of allograft rejections occur within 2 months after immunotherapy initiation.•Close monitoring and tailoring immunosuppression are critical.
We report a case of chromoblastomycosis in a 67-year-old female farmer, which involved a large (20 × 30 cm) cicatricial erythematous plaque on the inner side of her right thigh. The lesion was ...initially a small nodule which gradually extended over 36 years. Direct microscopic examination revealed a granulomatous lesion with muriform cells surrounded by giant cells. The mould recovered in cultures was dark olivaceous and identified as Fonsecaea monophora by ribosomal internal transcribe spacer (ITS) sequence data. The lesion was successfully cured after 4 months treatment with itraconazole, but there was a relapse.
Summary
Background Tinea capitis is the most common type of dermatophytosis in children, but is uncommon in the first year of life.
Objectives To review clinical, mycological and epidemiological ...data in a series of 10 infants aged under 1 year diagnosed as having tinea capitis in three Spanish hospitals between 1998 and 2002.
Methods A retrospective case note study.
Results There were six boys and four girls with a mean of age 7 months (range 1·5–12). All the children were born in Spain, but in five cases the parents were immigrants from Africa. In these cases the isolated dermatophytes were two Trichophyton tonsurans, one T. verrucosum and two Microsporum audouinii. Four autochthonous cases were caused by M. canis and one by M. audouinii (but this one was in contact with African immigrants). In two of the five cases produced by anthropophilic dermatophytes other family members were infected by the same fungus. Most cases were treated successfully with griseofulvin.
Conclusions Although tinea capitis is rare in infants in their first year of life, the condition should be investigated if scaling and/or alopecia are present. A thorough epidemiological study of other family members is mandatory.
Disruption of the immune system using immune checkpoint inhibitors (ICI) can result in a multitude of immune-related adverse effects (irAE). While irAEs have been well-reported in clinical trials, ...the impact and magnitude in the real world is unclear.
Data was collected on patients with advanced malignancy who experienced a suspected irAE requiring admission to an academic hospital (02/11-10/18). Each case was comprehensively reviewed by a minimum of two reviewers, including one sub-specialist.
From 2011-2018, there were 632 hospitalizations for suspected irAEs, and the majority (59.7%; N=377) were confirmed irAEs from immunotherapy: PD1 (N=194, 51.5%), CTLA4 (N=92, 24.4%), CTLA4 + PD1 (N=76, 20.2%), PLD1 (N=15, 4.0%). The most common irAEs were gastrointestinal (37.4%), pulmonary (14.9%), hepatic (13.5%), endocrine (16.2%), neurologic (9.0%), cardiac (6.9%), dermatologic (5.6%), rheumatologic (2.9%), hematologic (2.1%), renal (1.9%), and allergy (1.1%). 10.3% of admissions had multiple toxicities. Median length of stay was 5 days (IQR, 3-8). Majority of patients (89.1%) required continuation of immunosuppressive medication on discharge. Inpatient toxicity led to ICI discontinuation in 78.1% of admissions. Overall, there were 11.3 irAE admissions per 100 patients treated with ICI and 2.1 irAE admissions per 100 ICI administrations.
irAEs from ICI can result in prolonged hospitalizations, need for immunosuppression, and ICI discontinuation, which can have detrimental effects on oncologic outcomes. Consequently, there is a critical need for coordinated multidisciplinary approach, comprehensive provider education, and translational research programs for early detection and intervention.
The authors.
Has not received any funding.
All authors have declared no conflicts of interest.
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