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1.
J Appl Lab Med ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38816928

RESUMEN

BACKGROUND: Cardiac troponin T (cTnT) is key in diagnosing myocardial infarction (MI) but is also elevated in end-stage renal disease (ESRD) patients. Specific larger cTnT proteoforms were identified for the acute phase of MI, while in serum of ESRD patients solely small cTnT fragments were found. However, others allocated this to a pre-analytic effect due to abundant thrombin generation in serum. Therefore, we investigated the effect of various anticoagulation methods on cTnT composition and concentration and compared the cTnT composition of MI and ESRD patients. METHODS: The agreement of cTnT concentrations between simultaneously collected serum, lithium-heparin (LH) plasma, and ethylenediaminetetraacetic acid (EDTA) plasma was studied using the high-sensitivity (hs-)cTnT immunoassay. cTnT proteoform composition was investigated in a standardized time-dependent manner through spike experiments and in simultaneously collected blood matrixes of MI and ESRD patients. RESULTS: Excellent hs-cTnT concentration agreements were observed across all blood matrixes (slopes > 0.98; 95% CI, 0.96-1.04). Time-dependent degradation (40 kDa intact:29 kDa fragment:15 to 18 kDa fragments) was found in LH plasma and EDTA plasma, and serum in ratios (%) of 90:10:0, 0:5:95, and 0:0:100, respectively (48 h after blood collection). Moreover, gel filtration chromatography (GFC) profiles illustrated mainly larger cTnT proteoforms in MI patients, while in ESRD patients mainly 15 to 18 kDa fragments were found for all matrices. CONCLUSIONS: The extent of cTnT degradation in vitro is dependent on the (anti)coagulation method, without impacting hs-cTnT concentrations. Furthermore, mainly larger cTnT proteoforms were present in MI patients, while in ESRD patients mainly small 15 to 18 kDa cTnT fragments were found. These insights are essential when developing a novel hs-cTnT assay targeting larger cTnT proteoforms.

2.
J Physiol ; 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38411283

RESUMEN

We measured the impact of blood flow restriction on muscle protein synthesis rates, muscle mass and strength during 2 weeks of strict bed rest. Twelve healthy, male adults (age: 24 ± 3 years, body mass index: 23.7 ± 3.1 kg/m2 ) were subjected to 14 days of strict bed rest with unilateral blood flow restriction performed three times daily in three 5 min cycles (200 mmHg). Participants consumed deuterium oxide and we collected blood and saliva samples throughout 2 weeks of bed rest. Before and immediately after bed rest, lean body mass (dual-energy X-ray absorptiometry scan) and thigh muscle volume (magnetic resonance imaging scan) were assessed in both the blood flow restricted (BFR) and control (CON) leg. Muscle biopsies were collected and unilateral muscle strength (one-repetition maximum; 1RM) was assessed for both legs before and after the bed rest period. Bed rest resulted in 1.8 ± 1.0 kg lean body mass loss (P < 0.001). Thigh muscle volume declined from 7.1 ± 1.1 to 6.7 ± 1.0 L in CON and from 7.0 ± 1.1 to 6.7 ± 1.0 L in BFR (P < 0.001), with no differences between treatments (P = 0.497). In addition, 1RM leg extension strength decreased from 60.2 ± 10.6 to 54.8 ± 10.9 kg in CON and from 59.2 ± 12.1 to 52.9 ± 12.0 kg in BFR (P = 0.014), with no differences between treatments (P = 0.594). Muscle protein synthesis rates during bed rest did not differ between the BFR and CON leg (1.11 ± 0.12 vs. 1.08 ± 0.13%/day, respectively; P = 0.302). Two weeks of bed rest substantially reduces skeletal muscle mass and strength. Blood flow restriction during bed rest does not modulate daily muscle protein synthesis rates and does not preserve muscle mass or strength. KEY POINTS: Bed rest, often necessary for recovery from illness or injury, leads to the loss of muscle mass and strength. It has been postulated that blood flow restriction may attenuate the loss of muscle mass and strength during bed rest. We investigated the effect of blood flow restriction on muscle protein synthesis rates, muscle mass and strength during 2 weeks of strict bed rest. Blood flow restriction applied during bed rest does not modulate daily muscle protein synthesis rates and does not preserve muscle mass or strength. Blood flow restriction is not effective in preventing muscle atrophy during a prolonged period of bed rest.

3.
Med Sci Sports Exerc ; 56(4): 635-643, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38079310

RESUMEN

INTRODUCTION: Physical activity level has been identified as an important factor in the development and progression of various types of cancer. In this study, we determined the impact of a low versus high physical activity level on skeletal muscle, healthy prostate, and prostate tumor protein synthesis rates in vivo in prostate cancer patients. METHODS: Thirty prostate cancer patients (age, 66 ± 5 yr; body mass index, 27.4 ± 2.9 kg·m -2 ) were randomized to a low (<4000 steps per day, n = 15) or high (>14,000 steps per day, n = 15) physical activity level for 7 d before their scheduled radical prostatectomy. Daily deuterium oxide administration was combined with the collection of plasma, skeletal muscle, nontumorous prostate, and prostate tumor tissue during the surgical procedure to determine tissue protein synthesis rates throughout the intervention period. RESULTS: Daily step counts averaged 3610 ± 878 and 17,589 ± 4680 steps in patients subjected to the low and high physical activity levels, respectively ( P < 0.001). No differences were observed between tissue protein synthesis rates of skeletal muscle, healthy prostate, or prostate tumor between the low (1.47% ± 0.21%, 2.74% ± 0.70%, and 4.76% ± 1.23% per day, respectively) and high (1.42% ± 0.16%, 2.64% ± 0.58%, and 4.72% ± 0.80% per day, respectively) physical activity group (all P > 0.4). Tissue protein synthesis rates were nearly twofold higher in prostate tumor compared with nontumorous prostate tissue. CONCLUSIONS: A short-term high or low physical activity level does not modulate prostate or prostate tumor protein synthesis rates in vivo in prostate cancer patients. More studies on the impact of physical activity level on tumor protein synthesis rates and tumor progression are warranted to understand the potential impact of lifestyle interventions in the prevention and treatment of cancer.


Asunto(s)
Próstata , Neoplasias de la Próstata , Masculino , Humanos , Persona de Mediana Edad , Anciano , Neoplasias de la Próstata/terapia , Prostatectomía/métodos , Índice de Masa Corporal , Ejercicio Físico
4.
Glob Chang Biol ; 29(23): 6727-6740, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37823682

RESUMEN

Conditions conducive to fires are becoming increasingly common and widespread under climate change. Recent fire events across the globe have occurred over unprecedented scales, affecting a diverse array of species and habitats. Understanding biodiversity responses to such fires is critical for conservation. Quantifying post-fire recovery is problematic across taxa, from insects to plants to vertebrates, especially at large geographic scales. Novel datasets can address this challenge. We use presence-only citizen science data from iNaturalist, collected before and after the 2019-2020 megafires in burnt and unburnt regions of eastern Australia, to quantify the effect of post-fire diversity responses, up to 18 months post-fire. The geographic, temporal, and taxonomic sampling of this dataset was large, but sampling effort and species discoverability were unevenly spread. We used rarefaction and prediction (iNEXT) with which we controlled sampling completeness among treatments, to estimate diversity indices (Hill numbers: q = 0-2) among nine broad taxon groupings and seven habitats, including 3885 species. We estimated an increase in species diversity up to 18 months after the 2019-2020 Australian megafires in regions which were burnt, compared to before the fires in burnt and unburnt regions. Diversity estimates in dry sclerophyll forest matched and likely drove this overall increase post-fire, while no taxon groupings showed clear increases inconsistent with both control treatments post-fire. Compared to unburnt regions, overall diversity across all taxon groupings and habitats greatly decreased in areas exposed to extreme fire severity. Post-fire life histories are complex and species detectability is an important consideration in all post-fire sampling. We demonstrate how fire characteristics, distinct taxa, and habitat influence biodiversity, as seen in local-scale datasets. Further integration of large-scale datasets with small-scale studies will lead to a more robust understanding of fire recovery.


Asunto(s)
Conservación de los Recursos Naturales , Incendios , Animales , Australia , Biodiversidad , Ecosistema , Bosques
5.
Microb Ecol ; 86(4): 2910-2922, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37656196

RESUMEN

Bats harbor diverse intracellular Bartonella bacteria, but there is limited understanding of the factors that influence transmission over time. Investigation of Bartonella dynamics in bats could reveal general factors that control transmission of multiple bat-borne pathogens, including viruses. We used molecular methods to detect Bartonella DNA in paired bat (Pteropus medius) blood and bat flies in the family Nycteribiidae collected from a roost in Faridpur, Bangladesh between September 2020 and January 2021. We detected high prevalence of Bartonella DNA in bat blood (35/55, 64%) and bat flies (59/60, 98%), with sequences grouping into three phylogenetic clades. Prevalence in bat blood increased over the study period (33% to 90%), reflecting an influx of juvenile bats in the population and an increase in the prevalence of bat flies. Discordance between infection status and the clade/genotype of detected Bartonella was also observed in pairs of bats and their flies, providing evidence that bat flies take blood meals from multiple bat hosts. This evidence of bat fly transfer between hosts and the changes in Bartonella prevalence during a period of increasing nycteribiid density support the role of bat flies as vectors of bartonellae. The study provides novel information on comparative prevalence and genetic diversity of Bartonella in pteropodid bats and their ectoparasites, as well as demographic factors that affect Bartonella transmission and potentially other bat-borne pathogens.


Asunto(s)
Infecciones por Bartonella , Bartonella , Quirópteros , Animales , Filogenia , Bangladesh/epidemiología , Variación Genética , Infecciones por Bartonella/epidemiología , Infecciones por Bartonella/veterinaria , Infecciones por Bartonella/microbiología , Bartonella/genética , ADN
6.
Nutrients ; 15(16)2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37630843

RESUMEN

Vitamin C is a crucial micronutrient for human immune cell function and has potent antioxidant properties. It is hypothesized that vitamin C serum levels decline during infection. However, the precise mechanisms remain unknown. To gain deeper insights into the true role of vitamin C during infections, we aimed to evaluate the body's vitamin C storage during a SARS-CoV-2 infection. In this single-center study, we examined serum and intracellular vitamin C levels in peripheral blood mononuclear cells (PBMCs) of 70 hospitalized COVID-19 patients on the first and fifth days of hospitalization. Also, clinical COVID-19 severity was evaluated at these timepoints. Our findings revealed a high prevalence of hypovitaminosis C and vitamin C deficiency in hospitalized COVID-19 patients (36% and 15%). Moreover, patients with severe or critical disease exhibited a higher prevalence of low serum vitamin C levels than those with moderate illness. Serum vitamin C levels had a weak negative correlation with clinical COVID-19 severity classification on the day of hospitalization; however, there was no correlation with intracellular vitamin C. Intracellular vitamin C levels were decreased in this cohort as compared to a healthy cohort and showed further decline during hospitalization, while serum levels showed no relevant change. Based on this observation, it can be suggested that the reduction of intracellular vitamin C may be attributed to its antioxidative function, the need for replenishing serum levels, or enhanced turnover by immune cells. These data give an incentive to further investigate the role of intracellular vitamin C in a larger and more heterogeneous cohort as well as the underlying mechanisms.


Asunto(s)
Ácido Ascórbico , COVID-19 , Humanos , Leucocitos Mononucleares , SARS-CoV-2 , Vitaminas , Antioxidantes
7.
J Nutr ; 152(12): 2734-2743, 2023 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-36170964

RESUMEN

BACKGROUND: Plant-derived proteins are considered to have lesser anabolic properties when compared with animal-derived proteins. The attenuated rise in muscle protein synthesis rates following ingestion of plant-derived compared with animal-derived protein has been, at least partly, attributed to deficiencies in specific amino acids such as leucine, lysine, and/or methionine. Combining different plant-derived proteins could provide plant-derived protein blends with a more balanced amino acid profile. OBJECTIVES: This study aimed to compare postprandial muscle protein synthesis rates following the ingestion of 30 g milk protein with a 30 g blend combining wheat, corn, and pea protein in healthy young men. METHODS: In a randomized, double-blind, parallel-group design, 24 young males (aged 24 ± 4 y) received a primed continuous l-[ring-13C6]-phenylalanine infusion after which they ingested 30 g milk protein (MILK) or a 30 g plant-derived protein blend combining 15 g wheat, 7.5 g corn, and 7.5 g pea protein (PLANT-BLEND). Blood and muscle biopsies were collected frequently for 5 h to assess postprandial plasma amino acid profiles (secondary outcome) and subsequent muscle protein synthesis rates (primary outcome). Data were analyzed by 2-factor repeated measures ANOVA and 2-samples t tests. RESULTS: MILK increased plasma essential amino acid concentrations more than PLANT-BLEND over the 5 h postprandial period (incremental AUC = 151 ± 31 compared with 79 ± 12 mmol·300 min·L-1, respectively; P < 0.001). Ingestion of both MILK and PLANT-BLEND increased myofibrillar protein synthesis rates (P < 0.001), with no significant differences between treatments (0.053 ± 0.013%/h and 0.064 ± 0.016%/h, respectively; P = 0.08). CONCLUSIONS: Ingestion of 30 g plant-derived protein blend combining wheat-, corn-, and pea-derived protein increases muscle protein synthesis rates in healthy young males. The muscle protein synthetic response to the ingestion of 30 g of this plant-derived protein blend does not differ from the ingestion of an equivalent amount of a high-quality animal-derived protein.Clinical trial registry number for Nederlands Trial Register: NTR6548 (https://trialsearch.who.int/Trial2.aspx?TrialID=NTR6548).


Asunto(s)
Proteínas de la Leche , Proteínas de Guisantes , Animales , Masculino , Aminoácidos/metabolismo , Proteínas en la Dieta/metabolismo , Ingestión de Alimentos , Proteínas de la Leche/farmacología , Proteínas de la Leche/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Proteínas de Guisantes/metabolismo , Proteínas de Plantas/metabolismo , Periodo Posprandial , Método Doble Ciego
8.
Nutrients ; 14(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36432471

RESUMEN

Vitamin C is an important micronutrient for various immune cells. It increases phagocytic cell function and is necessary for T and natural killer (NK) cell development. Patients in need of an autologous hematopoietic stem cell transplantation (HSCT) are often vitamin C-depleted. We therefore hypothesized that vitamin C supplementation could improve immune recovery in autologous HSCT patients. This blinded, placebo-controlled trial included 44 patients randomized to receive vitamin C or a placebo. The following outcome measures used were clinical and immunological parameters, among others: time to neutrophil recovery, serum, and intracellular vitamin C values. Twenty-one patients received vitamin C, and 23 received a placebo. The time to neutrophil recovery did not differ between the two groups at 11.2 days (p = 0.96). There were no differences in hospitalization time (19.7 vs. 19.1 days, p = 0.80), the incidence of neutropenic fever (57% vs. 78%, p = 0.20), or 3-month overall survival (90.5% vs. 100%, p = 0.13). Bacteremia seemed to occur less in the vitamin C group (10% vs. 35%, p = 0.07). Our study shows no benefit from vitamin C supplementation on neutrophil recovery and hospitalization, despite possible lower rates of bacteremia in the vitamin C group. Therefore, we do not advise vitamin C supplementation in this treatment group.


Asunto(s)
Bacteriemia , Trasplante de Células Madre Hematopoyéticas , Linfoma , Mieloma Múltiple , Humanos , Trasplante Autólogo , Mieloma Múltiple/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Ácido Ascórbico , Neutrófilos , Linfoma/terapia , Vitaminas
9.
Spine Deform ; 10(6): 1407-1414, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35794423

RESUMEN

PURPOSE: To establish whether common degenerative lumbar spine conditions have a predictable sagittal profile and associated range of lordosis. The spinopelvic balance of a normal population and normal ranges are well described in the literature. There is also evidence that certain degenerative conditions can lead to a preponderance of loss of lordosis at specific spinal levels. There is limited literature on the range and magnitude of loss of lordosis for known degenerative lumbar spine pathologies. METHODS: A retrospective analysis of prospectively obtained radiographs from a dual surgeon database was performed and imaging analysed for spinopelvic parameters. Degenerative conditions studied were; Lumbar degenerative spondylolisthesis (L3/4 and L4/5 analysed separately), L5/S1 degenerative disc disease, L5/S1 isthmic spondylolisthesis. Pelvic incidence, sacral slope, pelvic tilt, segmental and global lumbar lordosis, vertebral lordosis and lumbar vertical axis were measured. RESULTS: The range of change in segmental lordosis was normally distributed for all studied degenerative spinal conditions except L5/S1 isthmic spondylolisthesis. L5/S1 degenerative disc disease affected younger adults (mean age 37), whilst degenerative spondylolisthesis at L3/4 and L4/5 affected older adults (mean ages 69.5 and 68.9 respectively). Removing an outlying high-grade L5/S1 isthmic spondylolisthesis made the data distribution approach a normal distribution. CONCLUSION: Most degenerative spinal pathologies cause a normally distributed spectrum of deformity which should be addressed and corrected with a tailored, individualised surgical plan for each patient. Universal treatment recommendations should be interpreted with caution.


Asunto(s)
Degeneración del Disco Intervertebral , Lordosis , Espondilolistesis , Humanos , Anciano , Adulto , Lordosis/diagnóstico por imagen , Espondilolistesis/diagnóstico por imagen , Espondilolistesis/cirugía , Degeneración del Disco Intervertebral/diagnóstico por imagen , Estudios Retrospectivos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía
10.
Med Sci Sports Exerc ; 54(9): 1572-1581, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35438672

RESUMEN

INTRODUCTION: Plant-derived proteins have received considerable attention as an alternative to animal-based proteins and are now frequently used in both plant-based diets and sports nutrition products. However, little information is available on the anabolic properties of potato-derived protein. This study compares muscle protein synthesis rates after the ingestion of 30 g potato protein versus 30 g milk protein at rest and during recovery from a single bout of resistance exercise in healthy, young males. METHODS: In a randomized, double-blind, parallel-group design, 24 healthy young males (24 ± 4 yr) received primed continuous l -[ ring - 13 C 6 ]-phenylalanine infusions while ingesting 30 g potato-derived protein or 30 g milk protein after a single bout of unilateral resistance exercise. Blood and muscle biopsies were collected for 5 h after protein ingestion to assess postprandial plasma amino acid profiles and mixed muscle protein synthesis rates at rest and during recovery from exercise. RESULTS: Ingestion of both potato and milk protein increased mixed muscle protein synthesis rates when compared with basal postabsorptive values (from 0.020% ± 0.011% to 0.053% ± 0.017%·h -1 and from 0.021% ± 0.014% to 0.050% ± 0.012%·h -1 , respectively; P < 0.001), with no differences between treatments ( P = 0.54). In the exercised leg, mixed muscle protein synthesis rates increased to 0.069% ± 0.019% and 0.064% ± 0.015%·h -1 after ingesting potato and milk protein, respectively ( P < 0.001), with no differences between treatments ( P = 0.52). The muscle protein synthetic response was greater in the exercised compared with the resting leg ( P < 0.05). CONCLUSIONS: Ingestion of 30 g potato protein concentrate increases muscle protein synthesis rates at rest and during recovery from exercise in healthy, young males. Muscle protein synthesis rates after the ingestion of 30 g potato protein do not differ from rates observed after ingesting an equivalent amount of milk protein.


Asunto(s)
Proteínas en la Dieta , Proteínas Musculares , Solanum tuberosum , Adulto , Proteínas en la Dieta/metabolismo , Método Doble Ciego , Ingestión de Alimentos , Humanos , Masculino , Proteínas de la Leche , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Entrenamiento de Fuerza , Solanum tuberosum/metabolismo , Adulto Joven
11.
Viruses ; 13(9)2021 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-34578299

RESUMEN

Phleboviruses (genus Phlebovirus, family Phenuiviridae) are emerging pathogens of humans and animals. Sand-fly-transmitted phleboviruses are found in Europe, Africa, the Middle East, and the Americas, and are responsible for febrile illness and nervous system infections in humans. Rio Grande virus (RGV) is the only reported phlebovirus in the United States. Isolated in Texas from southern plains woodrats, RGV is not known to be pathogenic to humans or domestic animals, but serologic evidence suggests that sheep (Ovis aries) and horses (Equus caballus) in this region have been infected. Rift Valley fever virus (RVFV), a phlebovirus of Africa, is an important pathogen of wild and domestic ruminants, and can also infect humans with the potential to cause severe disease. The introduction of RVFV into North America could greatly impact U.S. livestock and human health, and the development of vaccines and countermeasures is a focus of both the CDC and USDA. We investigated the potential for serologic reagents used in RVFV diagnostic assays to also detect cells infected with RGV. Western blots and immunocytochemistry assays were used to compare the antibody detection of RGV, RVFV, and two other New World phlebovirus, Punta Toro virus (South and Central America) and Anhanga virus (Brazil). Antigenic cross-reactions were found using published RVFV diagnostic reagents. These findings will help to inform test interpretation to avoid false positive RVFV diagnoses that could lead to public health concerns and economically costly agriculture regulatory responses, including quarantine and trade restrictions.


Asunto(s)
Reacciones Cruzadas/inmunología , Phlebovirus/inmunología , Juego de Reactivos para Diagnóstico/normas , Virus de la Fiebre del Valle del Rift/inmunología , Pruebas Serológicas/normas , Animales , Infecciones por Bunyaviridae/clasificación , Infecciones por Bunyaviridae/diagnóstico , Infecciones por Bunyaviridae/inmunología , Caballos/virología , Phlebovirus/clasificación , Phlebovirus/patogenicidad , Fiebre del Valle del Rift/diagnóstico , Fiebre del Valle del Rift/inmunología , Virus de la Fiebre del Valle del Rift/patogenicidad , Pruebas Serológicas/métodos , Ovinos/virología , Estados Unidos
12.
Syst Parasitol ; 98(5-6): 581-587, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34495441

RESUMEN

A new species of Basilia Miranda-Ribeiro, 1903 (Diptera: Nycteribiidae) belonging to the ferruginea group from Mexico is described and additional geographic records of Basilia rondanii Guimarães & D´Andretta, 1956 are presented. The type-specimens of the species were collected on an endemic Mexican vespertilionid bat, Myotis carteri La Val (Chiroptera: Vespertilionidae) in the State of Jalisco. Photographs in dorsal and ventral views and distribution maps of the new species and Basilia rondanii are presented.


Asunto(s)
Quirópteros , Dípteros , Animales , México , Especificidad de la Especie
13.
Pathogens ; 10(8)2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34451394

RESUMEN

In 2006, vesicular stomatitis New Jersey virus (VSNJV) caused outbreaks in Wyoming (WY) horses and cattle after overwintering in 2004 and 2005. Within two weeks of the outbreak onset, 12,203 biting flies and 194 grasshoppers were collected near three equine-positive premises in Natrona County, WY. Insects were identified to the species level and tested by RT-qPCR for VSNJV polymerase (L) and phosphoprotein (P) gene RNA. Collected dipterans known to be competent for VSV transmission included Simulium black flies and Culicoides biting midges. VSNJV L and P RNA was detected in two pools of female Simulium bivittatum and subjected to partial genome sequencing. Phylogenetic analysis based on the hypervariable region of the P gene from black flies showed 100% identity to the isolate obtained from the index horse case on the same premises. This is the first report of VSNJV in S. bivittatum in WY and the first field evidence of possible VSV maintenance in black fly populations during an outbreak.

14.
Adv Exp Med Biol ; 1306: 41-59, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33959905

RESUMEN

Cardiac troponin T (cTnT) is a sensitive and specific biomarker for detecting cardiac muscle injury. Its concentration in blood can be significantly elevated outside the normal reference range under several pathophysiological conditions. The classical analytical method in routine clinical analysis to detect cTnT in serum or plasma is a single commercial immunoassay, which is designed to quantify the intact cTnT molecule. The targeted epitopes are located in the central region of the cTnT molecule. However, in blood cTnT exists in different biomolecular complexes and proteoforms: bound (to cardiac troponin subunits or to immunoglobulins) or unbound (as intact protein or as proteolytic proteoforms). While proteolysis is a principal posttranslational modification (PTM), other confirmed PTMs of the proteoforms include N-terminal initiator methionine removal, N-acetylation, O-phosphorylation, O-(N-acetyl)-glucosaminylation, N(ɛ)-(carboxymethyl)lysine modification and citrullination. The immunoassay probably detects several of those cTnT biomolecular complexes and proteoforms, as long as they have the centrally targeted epitopes in common. While analytical cTnT immunoreactivity has been studied predominantly in blood, it can also be detected in urine, although it is unclear in which proteoform cTnT immunoreactivity is present in urine. This review presents an overview of the current knowledge on the pathophysiological lifecycle of cTnT. It provides insight into the impact of PTMs, not only on the analytical immunoreactivity, but also on the excretion of cTnT in urine as one of the waste routes in that lifecycle. Accordingly, and after isolating the proteoforms from urine of patients suffering from proteinuria and acute myocardial infarction, the structures of some possible cTnT proteoforms are reconstructed using mass spectrometry and presented.


Asunto(s)
Infarto del Miocardio , Troponina T , Humanos , Fosforilación , Procesamiento Proteico-Postraduccional , Proteolisis , Troponina T/metabolismo
15.
Ann Bot ; 128(4): 407-418, 2021 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-33714989

RESUMEN

BACKGROUND AND AIMS: In tundra systems, soil-borne lichens are often the dominant groundcover organisms, and act to buffer microclimate extremes within or at the surface of the soil. However, shrubs are currently expanding across tundra systems, potentially causing major shifts in the microclimate landscape. METHODS: Here, we compared soil temperature and moisture underneath the dwarf birch Betula nana and seven abundant lichen species in sub-alpine Norway. We also examined mixtures of lichens and dwarf birch - an intermediate phase of shrubification - and measured several functional traits relating to microclimate. KEY RESULTS: We found that all lichen species strongly buffered the daily temperature range, on average reducing maximum temperatures by 6.9 °C (± 0.7 s.d.) and increasing minimum temperatures by 1.0 °C (± 0.2 s.d.) during summer. The dwarf birch had a much weaker effect (maximum reduced by 2.4 ±â€…5.0 °C and minimum raised by 0.2 ± 0.9 °C). In species mixtures, the lichen effect predominated, affecting temperature extremes by more than would be expected from their abundance. Lichens also tended to reduce soil moisture, which could be explained by their ability to intercept rainfall. Our trait measurements under laboratory conditions suggest that, on average, lichens can completely absorb a 4.09 mm (± 1.81 s.d.) rainfall event, which might be an underappreciated part of lichen-vascular plant competition in areas where summer rainfall events are small. CONCLUSIONS: In the context of shrubification across tundra systems, our findings suggest that lichens will continue to have a large effect on microclimate until they are fully excluded, at which point microclimate extremes will increase greatly.


Asunto(s)
Betula , Líquenes , Microclima , Suelo , Tundra
16.
Ticks Tick Borne Dis ; 12(4): 101688, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33652332

RESUMEN

Argasid systematics remains controversial with widespread adherence to the Hoogstraal (1985) classification scheme, even though it does not reflect evolutionary relationships and results in paraphyly for the main genera of soft ticks (Argasidae), namely Argas and Ornithodoros. The alternative classification scheme, proposed by Klompen and Oliver (1993), has problems of its own: most notably paraphyly of the subgenus Pavlovskyella and the controversial grouping together of the subgenera Alectorobius, Antricola, Carios, Chiropterargas, Nothoaspis, Parantricola, Reticulinasus and Subparmatus into the genus Carios. Recent phylogenetic analyses of 18S/28S rRNA sequences and mitochondrial genomes agree with the scheme of Klompen and Oliver (1993), with regard to the paraphyly of Pavlovskyella, placement of Alveonasus, Ogadenus, Proknekalia and Secretargas in the Argasinae and placement of Carios and Chiropterargas in the Ornithodorinae (Mans et al., 2019). The Carios clade and its constituent subgenera remain controversial, since the phylogenetic position of its type species Carios (Carios) vespertilionis Latreille, 1796 (formerly Argas vespertilionis) has not been determined with confidence. The current study aimed to resolve Carios sensu lato Klompen and Oliver, 1993, and Carios sensu stricto Hoogstraal, 1985, by determining and analysing phylogenetic nuclear and mitochondrial markers for C. (C.) vespertilionis. Both the nuclear and mitochondrial markers support placement of Carios s.s. within the subfamily Ornithodorinae, but to the exclusion of the clade that includes the 6 other subgenera that are part of Carios s.l. Klompen and Oliver (1993), namely Alectorobius, Antricola, Nothoaspis, Parantricola, Reticulinasus and Subparmatus. These 6 subgenera form a monophyletic clade that might be placed as new subgenera within the genus Alectorobius, or elevated to genera. Given the substantial differences in biology among these subgenera, we propose that these 6 subgenera be elevated to genera. Thus, we propose to modify the classification scheme of Mans et al. (2019) so that the subfamily Argasinae now has six genera, Alveonasus, Argas (subgenera Argas and Persicargas), Navis, Ogadenus, Proknekalia and Secretargas, and the subfamily Ornithodorinae has nine genera, Alectorobius, Antricola (subgenera Antricola and Parantricola), Carios, Chiropterargas, Nothoaspis, Ornithodoros (subgenera Microargas, Ornamentum, Ornithodoros, Pavlovskyella and Theriodoros), Otobius, Reticulinasus and Subparmatus (genera indicated in bold).


Asunto(s)
Argasidae/clasificación , Genoma Mitocondrial , Animales , Argas/clasificación , Argas/genética , Argas/crecimiento & desarrollo , Argasidae/genética , Argasidae/crecimiento & desarrollo , Femenino , Marcadores Genéticos , Larva/clasificación , Larva/genética , Larva/crecimiento & desarrollo , Ornithodoros/clasificación , Ornithodoros/genética , Ornithodoros/crecimiento & desarrollo , Filogenia , ARN Ribosómico 18S/análisis , ARN Ribosómico 28S/análisis
17.
J Parasitol ; 106(5): 663-669, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33079998

RESUMEN

Ectoparasites were collected from Eptesicus hottentotus, the long-tailed serotine bat, caught in Namibia as part of an ecological study. Larvae of Argas transgariepinus, a blood-feeding ectoparasite of bats in Africa, were removed from 3 of 18 bats. We present scanning electron microscope images of unengorged larvae. As with other ectoparasites, this bat tick might transmit pathogens such as Borrelia and Rickettsia to their hosts as has been reported for bat ticks in Europe and North America. We screened 3 pools (25 total) of larvae of A. transgariepinus removed from the long-tailed serotine bat Eptesicus hottentotus caught in Namibia. Two microbes of unknown pathogenicity, including Rickettsia hoogstraalii, a spotted fever group pathogen, and a Rickettsiella sp. were detected by molecular techniques.


Asunto(s)
Argas/microbiología , Quirópteros/parasitología , Coxiellaceae/aislamiento & purificación , Infecciones por Rickettsia/transmisión , Rickettsia/aislamiento & purificación , Infestaciones por Garrapatas/veterinaria , Animales , Argas/ultraestructura , Infecciones por Borrelia/transmisión , Coxiella/genética , Coxiella/aislamiento & purificación , Coxiellaceae/genética , ADN Bacteriano/análisis , Femenino , Larva/ultraestructura , Masculino , Microscopía Electrónica de Rastreo/veterinaria , Namibia , Rickettsia/genética , Infestaciones por Garrapatas/parasitología
18.
J Huntingtons Dis ; 9(4): 345-352, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32986678

RESUMEN

BACKGROUND: Despite the abundance of clinical tools, sleep disorders are still not routinely evaluated in patients with Huntington's disease (HD). Sleep disturbances can exacerbate cognitive impairment and mood disorders and seriously affect the life of the patients and their families. OBJECTIVE: The current study was designed to investigate sleep quality and its association with clinical symptoms in HD. As an exploratory aim, we also evaluated sleep quality in caregivers of patients with HD. METHODS: Twenty-nine patients with HD and 22 caregivers completed a series of self-reported questionnaires about sleep quality and pattern, cognitive function, and depression and anxiety symptoms. Spearman correlation analyses were performed to ascertain the association between sleep quality and severity of self-perceived clinical symptoms. RESULTS: The primary sleep complaints reported by the patients were related to waking up in the middle of the night or early in the morning; and increased sleep latency. Seventeen of 29 HD patients (59%) and 12 of 22 caregivers (55%) were classified as "poor" sleepers. Worse sleep quality among HD patients was associated with greater severity of anxiety and depression symptoms. Importantly, a decline in sleep quality was associated with decreased self-perceived cognitive function for both HD patients and caregivers. CONCLUSION: Increasing awareness and improving our understanding of sleep dysfunction in HD is imperative for individuals with HD and indirectly, their caregivers. Regularly incorporating sleep assessments when evaluating HD patients should be considered to address this troublesome nonmotor symptom.


Asunto(s)
Ansiedad/psicología , Cuidadores , Depresión/psicología , Enfermedad de Huntington/fisiopatología , Autoinforme , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Adulto , Anciano , Cognición , Femenino , Humanos , Enfermedad de Huntington/psicología , Masculino , Persona de Mediana Edad , Calidad de Vida , Trastornos del Inicio y del Mantenimiento del Sueño/psicología , Latencia del Sueño , Trastornos del Sueño-Vigilia/fisiopatología , Trastornos del Sueño-Vigilia/psicología
19.
J Equine Vet Sci ; 90: 103026, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32534788

RESUMEN

Vesicular stomatitis viruses (VSVs) cause a condition known as vesicular stomatitis (VS), which results in painful lesions in equines, cattle, swine, and camelids, and when transmitted to humans, can cause flu-like symptoms. When animal premises are affected by VS, they are subject to a quarantine. The equine industry more broadly may incur economic losses due to interruptions of animal trade and transportation to shows, competitions, and other events. Equine owners, barn managers, and veterinarians can take proactive measures to reduce the risk of equines contracting VS. To identify appropriate risk management strategies, it helps to understand which biting insects are capable of transmitting the virus to animals, and to identify these insect vectors' preferred habitats and behaviors. We make this area of science more accessible to equine owners, barn managers, and veterinarians, by (1) translating the most relevant scientific information about biting insect vectors of VSV and (2) identifying practical management strategies that might reduce the risk of equines contracting VSV from infectious biting insects or from other equines already infected with VSV. We address transmission risk at four different spatial scales-the animal, the barn/shelter, the barnyard/premises, and the surrounding environment/neighborhood-noting that a multiscale and spatially collaborative strategy may be needed to reduce the risk of VS.


Asunto(s)
Enfermedades de los Bovinos , Enfermedades de los Caballos , Enfermedades de los Porcinos , Estomatitis Vesicular , Vesiculovirus , Animales , Bovinos , Enfermedades de los Caballos/prevención & control , Caballos , Insectos Vectores , Porcinos , Estados Unidos , Estomatitis Vesicular/prevención & control , Virus de la Estomatitis Vesicular Indiana
20.
J S Afr Vet Assoc ; 91(0): e1-e3, 2020 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-32501016

RESUMEN

Sixty-four individuals of a macronyssid mite, Parasteatonyssus nyctinomi (Zumpt, Patterson 1951), were identified from Egyptian free-tailed bats Tadarida aegyptiaca (É. Geoffroy 1818) (Chiroptera: Molossidae) captured in the Kunene region of Namibia (southern Africa). This is the first report on P. nyctinomi in the country.


Asunto(s)
Distribución Animal , Quirópteros/parasitología , Ácaros/fisiología , Animales , Femenino , Interacciones Huésped-Parásitos , Masculino , Ácaros/crecimiento & desarrollo , Namibia , Ninfa/crecimiento & desarrollo , Ninfa/fisiología
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