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1.
BMC Infect Dis ; 24(1): 519, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783176

RESUMO

BACKGROUND: Targeting mucosal immunity of the gut, which is known to provide antigen processing, while avoiding excessive or unnecessary inflammation, was tested as a way to modulate COVID-19 severity. METHODS: Randomized open-label trial in 204 adults hospitalized with non-critical COVID-19 who received for 14 days in addition to standard of care (SOC) degalactosylated bovine glycoproteins formulations of either MAF capsules (MAF group) or M capsules (M group) or SOC only (control group). RESULTS: Median recovery time when patients did not require supplemental oxygen was 6 days in both study groups compared to 9 days in the control (MAF vs. control; P = 0.020 and M vs. control; P = 0.004). A greater reduction in mortality was seen in the MAF group compared to the control by day 14 (8.3% vs. 1.6%; P = 0.121) and by day 29 (15.3% vs. 3.2%; P = 0.020), and similarly in the M group by day 14 (8.3% vs. 2.9%; P = 0.276) and by day 29 (15.3% vs. 2.9%; P = 0.017). The proportion of those who had baseline absolute lymphocyte count (ALC) lower than 0.8 × 109/L was 13/63 (20.6%), 17/69 (24.6%), and 18/72 (25.0%) of patients in MAF, M, and control group respectively. Day 29 mortality among these lymphopenic patients was three times higher than for the intent-to-treat population (21% vs. 7%) and consisted in above subgroups: 2/13 (15%), 2/17 (12%), and 6/18 (33%) of patients. The decreased mortality in both study subgroups correlated with greater ALC restoration above 0.8 × 109/L level seen on day 14 in 91% (11/12) and 87.5% (14/16) of survivors in MAF and M subgroups respectively compared to 53.3% (8/15) of survivors in control subgroup. Incidences of any ALC decrease below the baseline level on day 14 occurred in 25.4% of patients in the MAF group and 29.0% of patients in the M group compared to 45.8% in control and ALC depletion by ≥ 50% from the baseline level consisted of 7.9%, 5.8%, and 15.3% of cases in these groups respectively. CONCLUSION: This study showed that both study agents prevented ALC depletion and accelerated its restoration, which is believed to be one of the mechanisms of improved crucial clinical outcomes in hospitalized COVID-19 patients. TRIAL REGISTRATION: The trial was registered after the trial start in ClinicalTrials.gov NCT04762628, registered 21/02/2021, https://www. CLINICALTRIALS: gov/ct2/show/NCT04762628 .


Assuntos
COVID-19 , Glicoproteínas , Linfopenia , SARS-CoV-2 , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , COVID-19/mortalidade , COVID-19/imunologia , COVID-19/terapia , SARS-CoV-2/imunologia , Idoso , Glicoproteínas/imunologia , Glicoproteínas/uso terapêutico , Resultado do Tratamento , Tratamento Farmacológico da COVID-19 , Bovinos , Animais , Adulto , Hospitalização/estatística & dados numéricos , Cápsulas
2.
Insect Sci ; 29(3): 942-955, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34432950

RESUMO

Color polymorphism offers rich opportunities for studying the eco-evolutionary mechanisms that drive the adaptations of local populations to heterogeneous and changing environments. We explored the color morph diversity and composition in a Chrysomela lapponica leaf beetle across its entire distribution range to test the hypothesis that environmental and climatic variables shape spatiotemporal variation in the phenotypic structure of a polymorphic species. We obtained information on 13 617 specimens of this beetle from museums, private collections, and websites. These specimens (collected from 1830-2020) originated from 959 localities spanning 33° latitude, 178° longitude, and 4200 m altitude. We classified the beetles into five color morphs and searched for environmental factors that could explain the variation in the level of polymorphism (quantified by the Shannon diversity index) and in the relative frequencies of individual color morphs. The highest level of polymorphism was found at high latitudes and altitudes. The color morphs differed in their climatic requirements; composition of colour morphs was independent of the geographic distance that separated populations but changed with collection year, longitude, mean July temperature and between-year temperature fluctuations. The proportion of melanic beetles, in line with the thermal melanism hypothesis, increased with increasing latitude and altitude and decreased with increasing climate seasonality. Melanic morph frequencies also declined during the past century, but only at high latitudes and altitudes where recent climate warming was especially strong. The observed patterns suggest that color polymorphism is especially advantageous for populations inhabiting unpredictable environments, presumably due to the different climatic requirements of coexisting color morphs.


Assuntos
Besouros , Aclimatação , Altitude , Animais , Evolução Biológica , Besouros/genética , Cor , Temperatura
3.
Sci Rep ; 10(1): 6344, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286322

RESUMO

The acute diarrhea is a wide-spread disease. The prescription of enterosorbents is appropriate as a primary measure for the treatment of the acute diarrhea for effective prevention of the fluid and electrolyte loss, as well as method for symptom relief of the attack of the disease. Aim of the study - the antidiarrheal efficacy and safety study of high-dispersion silicon dioxide enterosorbent in tablet dosage form in patients with acute diarrhea. This was randomized, double-blind, placebo-controlled, 4-center study. Acute diarrhea was defined as three and more episodes of watery stool per day either during 48 hours or less before study entry in the patients having normal stool recently. It has been postulated that symptoms and signs of acute diarrhea have to be caused by direct infection of the gastrointestinal tract and did not associated with moderate-to-severe systemic states. 144 patients with established acute diarrhea were randomized into treatment group (enterosorbent "Carbowhite", n = 120) or placebo group. Date collection including severity diarrhea, systemic symptoms was performed at baseline and daily during 7 days. Stool examination and serological assay were performed at baseline. The primary end points were declared as time to complete recovery from acute diarrhea. It has been found that the use of the siliceous enterosorbent ("Carbowhite") allowed to reduce (p < 0.001) the treatment period averagely for 0.9 days (95% confidence interval 0.5-1.2 days) in comparison with placebo. Data of safety monitoring has revealed that both patient groups had negative stool culture, while initiation of antibiotic treatment was run more frequently in placebo group (8.3%) compared to investigational product group (4.1%, P = 0.044). The siliceous enterosorbent "Carbowhite" was well tolerated and reduced the recovery time of the acute episode of the diarrhea in the clinically significant form.


Assuntos
Antidiarreicos/uso terapêutico , Diarreia/tratamento farmacológico , Dióxido de Silício/uso terapêutico , Adulto , Antidiarreicos/administração & dosagem , Antidiarreicos/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dióxido de Silício/administração & dosagem , Dióxido de Silício/efeitos adversos , Comprimidos/administração & dosagem , Comprimidos/efeitos adversos , Comprimidos/uso terapêutico
4.
Sci Total Environ ; 673: 237-244, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30991315

RESUMO

Intraspecific diversity buffers populations from deleterious impacts of environmental change. Nevertheless, the consequences of climate warming for phenotypic and genetic diversity within populations and species remain poorly understood. The goal of our study was to explore among-year variations in the phenotypic structure of populations and their relationships with climate variability and population dynamics. We analysed multiyear (1992-2018) data on colour morph frequencies within populations of the leaf beetle, Chrysomela lapponica, from multiple sites in the Kola Peninsula (northwestern Russia). We observed a strong decline in the proportion of dark (melanic) morphs among overwintered beetles during the study period; this decline was consistent across all study sites. Using model selection procedures, we explained declines in the dark morph of overwintered beetles by increases in minimum spring (May-June) daily temperatures. Other climatic characteristics, pollution load, and beetle population density were unrelated to variation in colour morph frequencies. Among newly emerged beetles (August), dark morph frequencies also decreased with an increase in average spring temperatures, but were unrelated to mean temperatures during the larval development period (July). These results suggest that the two-fold decline in dark morph frequencies during the past 26 years has been driven by the 2.5 °C increase in spring temperatures, most likely because dark males lose the mating advantages over light males that they obtain during cold springs. The continued loss of dark morphs and related decrease in within-population diversity may render leaf beetle populations more vulnerable to future environmental changes, in particular to those expressed in extreme weather fluctuations. Our study demonstrates that declines in within-population diversity are already underway in subarctic areas, and that these declines are likely driven by climate warming.


Assuntos
Mudança Climática , Besouros/fisiologia , Aquecimento Global , Melaninas/análise , Animais , Cor , Monitoramento Ambiental , Dinâmica Populacional , Federação Russa
5.
Oecologia ; 183(1): 93-106, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27718063

RESUMO

The evolution of defensive traits is driven both by benefits gained from protection against enemies and by costs of defence production. We tested the hypothesis that specialisation of herbivores on toxic host plants, accompanied by the ability to acquire plant defensive compounds for herbivore defence, is favoured by the lower costs of sequestration compared to de novo synthesis of defensive compounds. We measured physiological costs of chemical defence as a reduction in larval performance in response to repeated removal of secretions (simulating predator attack) and compared these costs between five species synthesising defences de novo and three species sequestering salicylic glucosides (SGs) from their host plants. Experiments simulating low predator pressure revealed no physiological costs in terms of survival, weight and duration of development in any of study species. However, simulation of high predation caused reduction in relative growth rate in Chrysomela lapponica larvae producing autogenous defences more frequently, than in larvae sequestering SGs. Still meta-analysis of combined data showed no overall difference in costs of autogenous and sequestered defences. However, larvae synthesising their defences de novo demonstrated secretion-conserving behaviour, produced smaller amounts of secretions, replenished them at considerably lower rates and employed other types of defences (regurgitation, evasion) more frequently when compared to sequestering larvae. These latter results provide indirect evidence for biosynthetic constraints for amounts of defensive secretions produced de novo, resulting in low defence effectiveness. Lifting these constraints by sequestration may have driven some leaf beetle lineages toward sequestration of plant allelochemicals as the main defensive strategy.


Assuntos
Besouros , Larva , Animais , Evolução Biológica , Herbivoria , Folhas de Planta
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