Fire transforms effects of terrestrial subsidies on aquatic ecosystem structure and function.

Fire can lead to transitions between forest and grassland ecosystems and trigger positive feedbacks to climate warming by releasing CO2 into the atmosphere. Climate change is projected to increase the prevalence and severity of wildfires. However, fire effects on the fate and impact of terrestrial organic matter (i.e., terrestrial subsidies) in aquatic ecosystems are unclear. Here, we performed a gradient design experiment in freshwater pond mesocosms adding 15 different amounts of burned or unburned plant detritus and tracking the chronology of detritus effects at 10, 31, 59, and 89 days. We show terrestrial subsidies had time- and mass-dependent, non-linear impacts on ecosystem function that influenced dissolved organic carbon (DOC), ecosystem metabolism (net primary production and respiration), greenhouse gas concentrations (carbon dioxide [CO2 ], methane [CH4 ]), and trophic transfer. These impacts were shifted by fire treatment. Burning increased the elemental concentration of detritus (increasing %N, %P, %K), with cascading effects on ecosystem function. Mesocosms receiving burned detritus had lower [DOC] and [CO2 ] and higher dissolved oxygen (DO) through Day 59. Fire magnified the effects of plant detritus on aquatic ecosystem metabolism by stimulating photosynthesis and respiration at intermediate detritus-loading through Day 89. The effect of loading on DO was similar for burned and unburned treatments (Day 10); however, burned-detritus in the highest loading treatments led to sustained hypoxia (through Day 31), and long-term destabilization of ecosystem metabolism through Day 89. In addition, fire affected trophic transfer by increasing autochthonous nitrogen source utilization and reducing the incorporation of 15 N-labeled detritus into plankton biomass, thereby reducing the flux of terrestrial subsidies to higher trophic levels. Our results indicate fire chemically transforms plant detritus and alters the role of aquatic ecosystems in processing and storing carbon. Wildfire may therefore induce shifts in ecosystem functions that cross the boundary between aquatic and terrestrial habitats.

A chimeric antigen receptor uniquely recognizing MICA/B stress proteins provides an effective approach to target solid tumors.

BACKGROUND: The advent of chimeric antigen receptor (CAR) T cell therapies has transformed the treatment of hematological malignancies; however, broader therapeutic success of CAR T cells has been limited in solid tumors because of their frequently heterogeneous composition. Stress proteins in the MICA and MICB (MICA/B) family are broadly expressed by tumor cells following DNA damage but are rapidly shed to evade immune detection. METHODS: We have developed a novel CAR targeting the conserved α3 domain of MICA/B (3MICA/B CAR) and incorporated it into a multiplexed-engineered induced pluripotent stem cell (iPSC)-derived natural killer (NK) cell (3MICA/B CAR iNK) that expressed a shedding-resistant form of the CD16 Fc receptor to enable tumor recognition through two major targeting receptors. FINDINGS: We demonstrated that 3MICA/B CAR mitigates MICA/B shedding and inhibition via soluble MICA/B while simultaneously exhibiting antigen-specific anti-tumor reactivity across an expansive library of human cancer cell lines. Pre-clinical assessment of 3MICA/B CAR iNK cells demonstrated potent antigen-specific in vivo cytolytic activity against both solid and hematological xenograft models, which was further enhanced in combination with tumor-targeted therapeutic antibodies that activate the CD16 Fc receptor. CONCLUSIONS: Our work demonstrated 3MICA/B CAR iNK cells to be a promising multi-antigen-targeting cancer immunotherapy approach intended for solid tumors. FUNDING: Funded by Fate Therapeutics and NIH (R01CA238039).

Dermatosis más frecuentes en pacientes con trasplante renal.

OBJECTIVE: To determine the most frequent dermatoses in patients with kidney transplant in the dermatology consultation, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, in Mexico City, in the period from March 2016 to March 2020. METHOD: Descriptive, cross-sectional study that included 153 patients with a complete medical history with prior informed consent and authorization from the hospital ethics committee. RESULTS: All patients presented one or more dermatoses. The most frequent were infectious (mycosis, viral) and, in decreasing order, other dermatoses (keratosis pilaris, melasma), tumorous (benign), inflammatory (seborrheic dermatitis, eczema), probably secondary to drugs and autoimmune (alopecia areata). CONCLUSIONS: All kidney transplant patients presented at least one dermatosis, predominantly those of infectious origin. We recommend dermatological evaluation prior to transplantation for timely diagnosis and treatment of dermatoses that could increase the morbi-mortality of patients.

OBJETIVO: Determinar las dermatosis más frecuentes en pacientes con trasplante renal en la consulta de dermatología del Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, en Ciudad de México, en el período de marzo de 2016 a marzo de 2020. MÉTODO: Estudio descriptivo, transversal que incluyó 153 pacientes con historia clínica completa, previo consentimiento informado y autorización del comité de ética del hospital. RESULTADOS: Todos los pacientes presentaron una o más dermatosis. Las más frecuentes fueron las infecciosas (micosis, virales) y, en orden decreciente, otras dermatosis (queratosis pilar, melasma), tumorales (benignas), inflamatorias (dermatitis seborreica, eccemas), probablemente secundarias a fármacos y autoinmunitarias (alopecia areata). CONCLUSIONES: Todos los pacientes receptores de trasplante renal presentaron al menos una dermatosis, predominando las de origen infeccioso. Recomendamos una valoración dermatológica previa al trasplante para el diagnóstico y el tratamiento oportuno de las dermatosis que podrían aumentar la morbimortalidad de los pacientes.

National survey of blindness and visual impairment in Guatemala, 2015 / Pesquisa nacional sobre cegueira e deficiência visual na Guatemala, 2015

ABSTRACT - Purpose: To estimate the prevalence of blindness and visual impairment in older adults living in Guatemala. Methods: Participants ³50 years of age were selected using random cluster sampling and evaluated using the Rapid Assessment of Avoidable Blindness method. Visual acuity was measured, and the lens was examined. If presenting visual acuity was <20/60, it was also tested with a pinhole and fundoscopy was performed. Blindness and visual impairment were classified as moderate visual impairment (presenting visual acuity <20/60 to 20/200), severe visual impairment (presenting visual acuity <20/200 to 20/400), or blindness (presenting visual acuity <20/400). The primary cause of blindness or visual impairment in each eye was determined, and if the cause was cataracts, the barriers to treatment were assessed. Results: The study included 3,850 people ³50 years of age, of whom 3,760 (97.7%) were examined. The age- and sex-adjusted prevalence of blindness was 2.9% (95% confidence interval, 2.0%-3.8%), while 5.2% (4.0%-6.4%) presented with severe visual impairment, and 27.6% (23.3%-32.0%) presented with moderate visual impairment. Cataracts were the leading cause of blindness (77.6%), followed by other posterior segment diseases (6.0%). Cataracts caused 79.4% of cases of severe visual impairment, while uncorrected refractive errors caused 67.9% of cases of moderate visual impairment. Following cataract surgery, 75% of participants had a presenting visual acuity of 20/200 or better, and in 19.0% of participants, visual acuity was not better than 20/200 with correction. Cost was the main barrier to cataract surgery (56.7%). Conclusions: The prevalence of blindness in older adults is higher in Guatemala than in most Central American countries. Most cases of blindness and visual impairment were either preventable or treatable. Increased availability of affordable, high-quality cataract treatment would have a substantial impact on blindness prevention.

RESUMO - Objetivo: Estimar a prevalência de cegueira e de­fi­ciência visual em idosos que vivem na Guatemala. Métodos: Indivíduos com idade ³50 anos foram selecionados por amos­tragem aleatória por conglomerados, e os participantes do estudo foram avaliados pelo método de Avaliação Rápida da Cegueira Evitável. A acuidade visual foi medida e o cristalino foi examinado. Se a acuidade visual apresentada fosse <20/60, então também foi testada com um buraco estenopeico e a fundoscopia realizada. A cegueira e a deficiência visual foram classificadas como deficiência visual moderada com acuidade visual <20/60-20/200; deficiência visual grave com acuidade visual <20/200-20/400; ou cegueira com acuidade visual <20/400. A principal causa de cegueira ou deficiência visual em cada olho foi determinada, e naqueles com catarata, as barreiras ao tratamento foram avaliadas. Resultados: O estudo incluiu 3.850 pessoas com ³50 anos de idade; 3.760 (97,7%) foram examinadas. A prevalência de cegueira ajustada à idade e ao sexo foi de 2,9% (intervalo de confiança de 95%, 2,0-3,8%), 5,2% (4,0-6,4%) deficiência visual grave e 27,6% (23,3-32,0%) deficiência visual moderada. A catarata foi a principal de cegueira (77,6%), seguida de outras doenças do segmento posterior (6,0%). Catarata causada por 79,4% de deficiência visual grave, enquanto erros refrativos não corrigidos causaram 67,9% de deficiência visual moderada. Após a cirurgia de catarata, 75% dos participantes tiveram uma acuidade de 20/200, ou melhor, e 19,0% a deficiência visual não foi melhor do que 20/200 com a correção. O custo foi a principal barreira à cirurgia de catarata (56.7%). Conclusões: A prevalência de cegueira em idosos é maior na Guatemala do que na maioria dos outros países da América Central. A maioria dos casos de cegueira e deficiência visual era evitável ou tratável. O aumento da disponibilidade de tratamento de catarata a preços acessíveis e de alta qualidade teria um impacto substancial na prevenção da cegueira.

National survey of blindness and visual impairment in Guatemala, 2015.

PURPOSE: To estimate the prevalence of blindness and visual impairment in older adults living in Guatemala. METHODS: Participants ³50 years of age were selected using random cluster sampling and evaluated using the Rapid Assessment of Avoidable Blindness method. Visual acuity was measured, and the lens was examined. If presenting visual acuity was <20/60, it was also tested with a pinhole and fundoscopy was performed. Blindness and visual impairment were classified as moderate visual impairment (presenting visual acuity <20/60 to 20/200), severe visual impairment (presenting visual acuity <20/200 to 20/400), or blindness (presenting visual acuity <20/400). The primary cause of blindness or visual impairment in each eye was determined, and if the cause was cataracts, the barriers to treatment were assessed. RESULTS: The study included 3,850 people ³50 years of age, of whom 3,760 (97.7%) were examined. The age- and sex-adjusted prevalence of blindness was 2.9% (95% confidence interval, 2.0%-3.8%), while 5.2% (4.0%-6.4%) presented with severe visual impairment, and 27.6% (23.3%-32.0%) presented with moderate visual impairment. Cataracts were the leading cause of blindness (77.6%), followed by other posterior segment diseases (6.0%). Cataracts caused 79.4% of cases of severe visual impairment, while uncorrected refractive errors caused 67.9% of cases of moderate visual impairment. Following cataract surgery, 75% of participants had a presenting visual acuity of 20/200 or better, and in 19.0% of participants, visual acuity was not better than 20/200 with correction. Cost was the main barrier to cataract surgery (56.7%). CONCLUSIONS: The prevalence of blindness in older adults is higher in Guatemala than in most Central American countries. Most cases of blindness and visual impairment were either preventable or treatable. Increased availability of affordable, high-quality cataract treatment would have a substantial impact on blindness prevention.

The surgery clerkship: an opportunity for preclinical credentialing in urinary catheterization.

BACKGROUND: At our hospital, medical students lost privileges to perform urinary catheterization because of concern regarding catheter-associated urinary tract infections. We hypothesized that trained medical students could perform urinary catheterization with the same proficiency as licensed practitioners. METHODS: Medical students completed a credentialing program in urinary catheterization. Prospectively, the rate of catheter-associated urinary tract infections after urinary catheterization performed by medical students was compared with the health system-wide rate of catheter-associated urinary tract infections after urinary catheterization performed by non-medical students using an incidence rate ratio (IRR). RESULTS: Over 9 months, a total of 432 and 55,401 catheter days accrued in patients who underwent urinary catheterization by medial students and non-medical students, resulting in 1 and 129 catheter-associated urinary tract infections, respectively. The incidence rate of catheter-associated urinary tract infections per 1,000 catheter days was 2.31 in the medical student-placed catheters and 2.33 in the non-MS-placed catheters (IRR = .99, P = .55). CONCLUSIONS: Preclinical credentialing in urinary catheterization resulted in the reinstatement of urinary catheterization privileges to qualified medical students. Student proficiency in urinary catheterization can match that of licensed practitioners.