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1.
Diabetes Obes Metab ; 26(6): 2412-2421, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38558508

RESUMEN

AIM: To evaluate the equivalence of immunogenicity, safety and efficacy of Gan & Lee (GL) Glargine (Basalin®; Gan & Lee Pharmaceutical) with that of the reference product (Lantus®) in adult participants with type 2 diabetes mellitus. METHODS: This was a phase 3, multicenter, open-label, equivalence trial conducted across 57 sites. In total, 567 participants with type 2 diabetes mellitus were randomized in a 1:1 ratio to undergo treatment with either GL Glargine or Lantus® for 26 weeks. The primary endpoint was the proportion of participants in each treatment arm who manifested treatment-induced anti-insulin antibodies (AIA). Secondary endpoints included efficacy and safety metrics, changes in glycated haemoglobin levels, and a comparative assessment of adverse events. Results were analysed using an equivalence test comparing the limits of the 90% confidence interval (CI) for treatment-induced AIA development to the prespecified margins. RESULTS: The percentages of participants positive for treatment-induced glycated haemoglobin by week 26 were similar between the GL Glargine (19.2%) and Lantus® (21.3%) treatment groups, with a treatment difference of -2.1 percentage points and a 90% CI (-7.6%, 3.5%) (predefined similarity margins: -10.7%, 10.7%). The difference in glycated haemoglobin was -0.08% (90% CI, -0.23, 0.06). The overall percentage of participants with any treatment-emergent adverse events was similar between the GL Glargine (80.1%) and Lantus® (81.6%) treatment groups. CONCLUSIONS: GL Glargine was similar to Lantus® in terms of immunogenicity, efficacy, and safety, based on the current study.


Asunto(s)
Biosimilares Farmacéuticos , Diabetes Mellitus Tipo 2 , Hemoglobina Glucada , Hipoglucemiantes , Insulina Glargina , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biosimilares Farmacéuticos/uso terapéutico , Biosimilares Farmacéuticos/efectos adversos , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/inmunología , Hemoglobina Glucada/efectos de los fármacos , Hemoglobina Glucada/metabolismo , Hemoglobina Glucada/análisis , Hipoglucemia/inducido químicamente , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/efectos adversos , Anticuerpos Insulínicos/sangre , Insulina Glargina/uso terapéutico , Insulina Glargina/efectos adversos , Equivalencia Terapéutica , Resultado del Tratamiento
2.
Endocr Pract ; 30(9): 810-816, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38876181

RESUMEN

OBJECTIVE: To compare the immunogenicity, safety, and efficacy of Gan & Lee insulin glargine (GL Glargine) with that of the originator insulin glargine (Lantus) in patients with type 1 diabetes mellitus (T1DM). METHODS: This was a phase 3, multicenter, randomized, open-label, equivalence study. Five hundred seventy-six subjects with T1DM were randomized 1:1 to receive either GL Glargine or Lantus treatment for 26 weeks. The primary end point was the percentage of subjects in each treatment group who developed treatment-induced anti-insulin antibody after baseline and up to visit week 26, which was evaluated using a country-adjusted logistic regression model. The study also compared the changes in glycated hemoglobin, and adverse events including hypoglycemia. RESULTS: The percentage of subjects positive for treatment-induced anti-insulin antibody by Week 26 was 25.8% in the GL Glargine treatment group and 25.3% in the Lantus treatment group, with a 90% confidence interval (-5.4, 6.5) of the difference in proportions that fell completely between the similarity margins (-11.3, 11.3). The least squares mean difference between treatment groups for changes in glycated hemoglobin was -0.08 (90% confidence interval: -0.23, 0.06), and the other immunogenicity and safety profiles were comparable. CONCLUSION: GL Glargine demonstrated similar immunogenicity, efficacy, and safety compared to Lantus over 26 weeks in patients with T1DM.


Asunto(s)
Biosimilares Farmacéuticos , Diabetes Mellitus Tipo 1 , Hipoglucemiantes , Insulina Glargina , Humanos , Insulina Glargina/uso terapéutico , Insulina Glargina/efectos adversos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/sangre , Masculino , Femenino , Adulto , Biosimilares Farmacéuticos/uso terapéutico , Biosimilares Farmacéuticos/efectos adversos , Persona de Mediana Edad , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/efectos adversos , Hemoglobina Glucada/análisis , Anticuerpos Insulínicos/sangre , Anticuerpos Insulínicos/inmunología , Adulto Joven , Resultado del Tratamiento , Adolescente , Hipoglucemia/inducido químicamente , Hipoglucemia/inmunología
3.
Ecol Appl ; 32(8): e2717, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36184740

RESUMEN

We report on survival and growth of ponderosa pines (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) 2 decades after forest restoration treatments in the G. A. Pearson Natural Area, northern Arizona. Despite protection from harvest that conserved old trees, a dense forest susceptible to uncharacteristically severe disturbance had developed during more than a century of exclusion of the previous frequent surface-fire regime that ceased upon Euro-American settlement in approximately 1876. Trees were thinned in 1993 to emulate prefire-exclusion forest conditions, accumulated forest floor was removed, and surface fire was re-introduced at 4-years intervals (full restoration). There was also a partial restoration treatment consisting of thinning alone. Compared with untreated controls, mortality of old trees (mean age 243 years, maximum 462 years) differed by <1 tree ha-1 and old-tree survival was statistically indistinguishable between treatments (90.5% control, 92.3% full, 82.6% partial). Post-treatment growth as measured by basal area increment of both old (pre-1876) and young (post-1876) pines was significantly higher in both treatments than counterpart control trees for more than 2 decades following thinning. Drought meeting the definition of megadrought affected the region almost all the time since the onset of the experiment, including 3 years that were severely dry. Growth of all trees declined in the driest 3 years, but old and young treated trees had significantly less decline. Association of tree growth with temperature (negative correlation) and precipitation (positive correlation) was much weaker in treated trees, indicating that they may experience less growth decline from warmer, drier conditions predicted in future decades. Overall, tree responses after the first 2 decades following treatment suggest that forest restoration treatments have led to substantial, sustained improvement in the growth of old and young ponderosa pines without affecting old-tree survival, thereby improving resilience to a warming climate.


Asunto(s)
Sequías , Pinus ponderosa , Pinus ponderosa/fisiología , Arizona , Bosques , Árboles/fisiología
4.
Parasitol Res ; 121(8): 2307-2323, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35754087

RESUMEN

Variable platyfish, Xiphophorus variatus (Meek, 1904) (Cyprinodontiformes: Poeciliidae) and eastern mosquitofish, Gambusia holbrooki Girard, 1859 (Poeciliidae) from earthen ponds in west central Florida were examined for parasitic infections. At necropsy, we observed myriad nematodes (adults and eggs), which we identified as Huffmanela cf. huffmani, infecting the swim bladder, gonad, and visceral peritoneum. Nucleotide sequences (small subunit ribosomal DNA, 18S) of H. cf. huffmani from variable platyfish and eastern mosquitofish were identical; likewise for newly obtained 18S sequences of Huffmanela huffmani Moravec, 1987 from the swim bladder of red breast sunfish, Lepomis auritus (Linnaeus, 1758) (Centrarchiformes: Centrarchidae) and warmouth, Lepomis gulosus (Cuvier, 1829) from the San Marcos River (type locality for Huffmanela huffmani Moravec, 1987), Texas. The sequences of H. huffmani and H. cf. huffmani differed by 7 (1%) nucleotides. Pathological changes comprised proliferation of the tunica externa of the swim bladder in low-intensity infections in addition to inflammation, proliferation, and tissue necrosis of swim bladder, peritoneum, and gonad in high-intensity infections. The lesion was severe, affecting the cellular constituents of the swim bladder wall and reducing the size of the swim bladder lumen; potentially reducing swim bladder physiological efficiency. The present study is the first record of a freshwater species of Huffmanela Moravec, 1987 from beyond the San Marcos River, first record of a species of Huffmanela from a livebearer, first nucleotide sequences and phylogenetic analysis for Huffmanela, and first evidence that an infection by a species of Huffmanela causes pathological changes that could impact organ function.


Asunto(s)
Ciprinodontiformes , Enfermedades de los Peces , Nematodos , Perciformes , Animales , Enfermedades de los Peces/parasitología , Florida , Gónadas , Perciformes/parasitología , Peritoneo , Filogenia , Vejiga Urinaria
5.
Ecol Appl ; 31(8): e02433, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34339088

RESUMEN

We review science-based adaptation strategies for western North American (wNA) forests that include restoring active fire regimes and fostering resilient structure and composition of forested landscapes. As part of the review, we address common questions associated with climate adaptation and realignment treatments that run counter to a broad consensus in the literature. These include the following: (1) Are the effects of fire exclusion overstated? If so, are treatments unwarranted and even counterproductive? (2) Is forest thinning alone sufficient to mitigate wildfire hazard? (3) Can forest thinning and prescribed burning solve the problem? (4) Should active forest management, including forest thinning, be concentrated in the wildland urban interface (WUI)? (5) Can wildfires on their own do the work of fuel treatments? (6) Is the primary objective of fuel reduction treatments to assist in future firefighting response and containment? (7) Do fuel treatments work under extreme fire weather? (8) Is the scale of the problem too great? Can we ever catch up? (9) Will planting more trees mitigate climate change in wNA forests? And (10) is post-fire management needed or even ecologically justified? Based on our review of the scientific evidence, a range of proactive management actions are justified and necessary to keep pace with changing climatic and wildfire regimes and declining forest heterogeneity after severe wildfires. Science-based adaptation options include the use of managed wildfire, prescribed burning, and coupled mechanical thinning and prescribed burning as is consistent with land management allocations and forest conditions. Although some current models of fire management in wNA are averse to short-term risks and uncertainties, the long-term environmental, social, and cultural consequences of wildfire management primarily grounded in fire suppression are well documented, highlighting an urgency to invest in intentional forest management and restoration of active fire regimes.


Asunto(s)
Incendios , Incendios Forestales , Cambio Climático , Bosques , América del Norte
6.
J Econ Perspect ; 32(2): 115-34, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30203932

RESUMEN

Many decisions of individuals involve a combination of internal preferences and mental processes related to cognitive ability. As Frederick (2005) argued in this journal, "there is no good reason for ignoring the possibility that general intelligence or various more specific cognitive abilities are important causal determinants of decision making." Since then, a number of empirical studies have focused on the relationship between cognitive ability and decision-making in different contexts. This paper will focus on the relationship between cognitive ability and decision-making under risk and uncertainty. Taken as a whole, this research indicates that cognitive ability is associated with risk-taking behavior in various contexts and life domains, including incentivized choices between lotteries in controlled environments, behavior in nonexperimental settings, and self-reported tendency to take risks. We begin by clarifying some important distinctions between concepts and measurement of risk preference and cognitive ability. In particular, complexity and possible confusions arise because observed measures of risk preference and cognitive ability are used to represent the latent characteristics of these concepts. We discuss the substantial (and somewhat implausible) range of assumptions that need to be satisfied in order to be able to interpret a correlation between measures of risk preference and cognitive ability as a relationship between latent risk preference and latent cognitive ability. Drawing causal inferences from such relationships raises additional challenges. We go on to argue that it is nevertheless important and valuable to study whether cognitive ability is related to measured risk preference (see also Dohmen, Falk, Huffman, and Sunde 2010). Risk preference is typically measured by risky behavior (actual or self-reported). If risky behavior varies systematically with cognitive ability, this may reinforce or counteract the impact of cognitive ability on life outcomes, depending on the nature of the correlation. If there is a relationship, it also becomes important to control for cognitive ability when relating life outcomes to standard revealed preference measures of risk preference. If cognitive ability has a causal impact on measured risk preference, it is important to understand the mechanism, and some intriguing policy implications arise. We then take stock of what is known empirically on the connections between cognitive ability and measured risk preferences, looking at studies using real-world risky behavior, experimental measures of risky choice, and self-reported measures of willingness to take risks. One pattern that emerges frequently in these studies is that cognitive ability tends to be positively correlated with avoidance of harmful risky situations, but it tends to be negatively correlated with risk aversion in advantageous situations. This suggests that the relationship between cognitive ability and risk taking has a reinforcing effect on economic outcomes. There is also intriguing emerging evidence that measured risk preference is particularly strongly related to certain facets of cognitive ability, those that facilitate quantitative problem solving, with implications for understanding mechanisms and possibly for better targeting policy interventions. We conclude by discussing perspectives for future research, in particular the scope for the development of richer sets of elicitation instruments and measurement across a wider range of concepts. We also consider progress in neuroscience, but conclude that at present that field still seems relatively far from allowing definitive conclusions about latent risk preference and cognitive ability. Nevertheless, the existing empirical evidence suggests that interventions to influence cognitive ability, should they be possible, might have spillovers on risky choice.


Asunto(s)
Encéfalo/fisiología , Conducta de Elección/fisiología , Cognición/fisiología , Asunción de Riesgos , Envejecimiento , Toma de Decisiones , Humanos
7.
Mol Microbiol ; 102(4): 628-641, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27528008

RESUMEN

The Great Oxidation Event resulted in integration of soft metals in a wide range of biochemical processes including, in our opinion, killing of bacteria by protozoa. Compared to pressure from anthropologic copper contamination, little is known on impacts of protozoan predation on maintenance of copper resistance determinants in bacteria. To evaluate the role of copper and other soft metals in predatory mechanisms of protozoa, we examined survival of bacteria mutated in different transition metal efflux or uptake systems in the social amoeba Dictyostelium discoideum. Our data demonstrated a strong correlation between the presence of copper/zinc efflux as well as iron/manganese uptake, and bacterial survival in amoebae. The growth of protozoa, in turn, was dependent on bacterial copper sensitivity. The phagocytosis of bacteria induced upregulation of Dictyostelium genes encoding the copper uptake transporter p80 and a triad of Cu(I)-translocating PIB -type ATPases. Accumulated Cu(I) in Dictyostelium was monitored using a copper biosensor bacterial strain. Altogether, our data demonstrate that Cu(I) is ultimately involved in protozoan predation of bacteria, supporting our hypothesis that protozoan grazing selected for the presence of copper resistance determinants for about two billion years.


Asunto(s)
Bacterias/efectos de los fármacos , Bacterias/metabolismo , Cobre/farmacología , Dictyostelium/microbiología , Bacterias/genética , Infecciones Bacterianas , Dictyostelium/metabolismo , Resistencia a Medicamentos , Evolución Molecular , Fagocitosis/efectos de los fármacos , Proteínas Protozoarias/metabolismo
8.
Clin Trials ; 14(1): 29-36, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27646508

RESUMEN

Background Obesity continues to be a serious public health challenge. Rates are increasing worldwide, with nearly 70% of the US adults overweight or obese, leading to increased clinical and economic burden. While successful approaches for achieving weight loss have been identified, techniques for long-term maintenance of initial weight loss have largely been unsuccessful. Financial incentive interventions have been shown in several settings to be successful in motivating participants to adopt healthy behaviors. Purpose Keep It Off is a three-arm randomized controlled trial that compares the efficacy of a lottery-based incentive, traditional direct payment incentive, and control of daily feedback without any incentive for weight-loss maintenance. This design allows comparison of a traditional direct payment incentive with one based on behavioral economic principles that consider the underlying psychology of decision-making. Methods Participants were randomized in a 2:1 ratio for each active arm relative to control, with a targeted 188 participants in total. Eligible participants were those aged 30-80 who lost at least 11 lb (5 kg) during the first 4 months of participation in Weight Watchers, a national weight-loss program, with whom we partnered. The interventions lasted 6 months (Phase I); participants were followed for an additional 6 months without intervention (Phase II). The primary outcome is weight change from baseline to the end of Phase I, with the change at the end of Phase II a key secondary endpoint. Keep It Off is a pragmatic trial that recruited, consented, enrolled, and followed patients electronically. Participants were provided a wireless weight scale that electronically transmitted daily self-monitored weights. Weights were verified every 3 months at a Weight Watchers center local to the participant and electronically transmitted. Results Using the study web-based platform, we integrated recruitment, enrollment, and follow-up procedures into a digital platform that required little staff effort to implement and manage. We randomized 191 participants in less than 1 year. We describe the design of Keep It Off and implementation of enrollment. Lessons Learned We demonstrated that our pragmatic design was successful in rapid accrual of participants in a trial of interventions to maintain weight loss. Limitations Despite the nationwide reach of Weight Watchers, the generalizability of study findings may be limited by the characteristics of its members. The interventions under study are appropriate for settings where an entity, such as an employer or health insurance company, could offer them as a benefit. Conclusions Keep It Off was implemented and conducted with minimal staff effort. This study has the potential to identify a practical and effective weight-loss maintenance strategy.


Asunto(s)
Toma de Decisiones , Conductas Relacionadas con la Salud , Motivación , Obesidad/terapia , Programas de Reducción de Peso , Adulto , Anciano , Anciano de 80 o más Años , Economía del Comportamiento , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pérdida de Peso
9.
Folia Parasitol (Praha) ; 632016 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-27312028

RESUMEN

The life cycle of the swim bladder nematode Huffmanela huffmani Moravec, 1987 (Trichinelloidea: Trichosomoididae), an endemic parasite of centrarchid fishes in the upper spring run of the San Marcos River in Hays County, Texas, USA, was experimentally completed. The amphipods Hyalella cf. azteca (Saussure), Hyalella sp. and Gammarus sp. were successfully infected with larvated eggs of Huffmanela huffmani. After ingestion of eggs of H. huffmani by experimental amphipods, the first-stage larvae hatch from their eggshells and penetrate through the digestive tract to the hemocoel of the amphipod. Within about 5 days in the hemocoel of the experimental amphipods at 22 °C, the larvae presumably attained the second larval stage and were infective for the experimental centrarchid definitive hosts, Lepomis spp. The minimum incubation period before adult nematodes began laying eggs in the swim bladders of the definitive hosts was found to be about 7.5 months at 22 °C. This is the first experimentally completed life cycle within the Huffmanelinae.


Asunto(s)
Anfípodos/parasitología , Enfermedades de los Peces/parasitología , Estadios del Ciclo de Vida , Nematodos/fisiología , Infecciones por Nematodos/parasitología , Perciformes/parasitología , Sacos Aéreos/parasitología , Animales , Texas , Tiempo
10.
Chemistry ; 19(27): 9042-9, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23677531

RESUMEN

Although metal ion homeostasis in cells is often mediated through metallochaperones, there are opportunities for toxic metals to be sequestered through the existing transport apparatus. Proper trafficking of Cu(I) in human cells is partially achieved through complexation by HAH1, the human metallochaperone responsible for copper delivery to the Wilson and Menkes ATPase located in the trans-Golgi apparatus. In addition to binding copper, HAH1 strongly complexes Hg(II), with the X-ray structure of this complex previously described. It is important to clarify the solution behavior of these systems and, therefore, the binding of Hg(II) to HAH1 was probed over the pH range 7.5 to 9.4 using (199)Hg NMR, (199m)Hg PAC and UV-visible spectroscopies. The metal-dependent protein association over this pH range was examined using analytical gel-filtration. It can be concluded that at pH 7.5, Hg(II) is bound to a monomeric HAH1 as a two coordinate, linear complex (HgS2), like the Hg(II)-Atx1 X-ray structure (PDB ID: 1CC8). At pH 9.4, Hg(II) promotes HAH1 association, leading to formation of HgS3 and HgS4 complexes, which are in exchange on the µs-ns time scale. Thus, structures that may represent central intermediates in the process of metal ion transfer, as well as their exchange kinetics have been characterized.


Asunto(s)
Cobre/química , Mercurio/química , Metalochaperonas/química , Complejos de Coordinación/química , Proteínas Transportadoras de Cobre , Humanos , Concentración de Iones de Hidrógeno , Modelos Moleculares , Chaperonas Moleculares , Soluciones
11.
Parasite ; 30: 6, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36920277

RESUMEN

A literature review for a recent ultrastructural study of a trichinelloid eggshell revealed consistently occurring errors in the literature on nematode eggshell anatomy. Examples included nematodes of medical, veterinary, and agricultural importance in several orders. Previous researchers had warned of some of these errors decades ago, but a comprehensive solution was not offered until 2012 when a clarifying new anatomical and developmental interpretation of nematode eggshells was proposed by members of the Caenorhabditis elegans Research Community. However, their findings were explained using arcane acronyms and technical jargon intended for an audience of experimental molecular geneticists, and so their papers have rarely been cited outside the C. elegans community. Herein we (1) provide a critical review of nematode eggshell literature in which we correct errors and relabel imagery in important historical reports; (2) describe common reporting errors and their causes using language familiar to researchers having a basic understanding of microscopy and nematode eggs; (3) recommend a new hexalaminar anatomical and terminological framework for nematode eggshells based on the 2012 C. elegans framework; and (4) recommend new unambiguous terms appropriate for the embryonated/larvated eggs regularly encountered by practicing nematodologists to replace ambiguous or ontogenetically restricted terms in the 2012 C. elegans framework. We also (5) propose a resolution to conflicting claims made by the C. elegans team versus classical literature regarding Layer #3, (6) extend the C. elegans hexalaminar framework to include the polar plugs of trichinelloids, and (7) report new findings regarding trichinelloid eggshell structure.


Title: La coque des œufs des nématodes : un nouveau cadre anatomique et terminologique, avec une revue critique de la littérature pertinente et des lignes directrices suggérées pour l'interprétation et la communication de l'imagerie des coques des œufs. Abstract: Une revue de la littérature pour une étude ultrastructurale récente de la coque de l'œuf d'un trichinelloïde a révélé des erreurs récurrentes dans la littérature sur l'anatomie de la coque de l'œuf des nématodes. Les exemples comprenaient des nématodes d'importance médicale, vétérinaire et agricole dans plusieurs ordres. Des chercheurs avaient mis en garde contre certaines de ces erreurs il y a des décennies, mais une solution complète n'a été proposée qu'en 2012, lorsqu'une nouvelle interprétation anatomique et développementale clarifiant la structure des coques des œufs de nématodes a été proposée par des membres de la communauté de recherche de Caenorhabditis elegans. Cependant, leurs découvertes ont été expliquées à l'aide d'acronymes mystérieux et d'un jargon technique destiné à un public de généticiens moléculaires expérimentaux, et leurs articles ont donc rarement été cités en dehors de la communauté de C. elegans. Ici, nous (1) fournissons une revue critique de la littérature sur les coques des œufs de nématodes dans laquelle nous corrigeons les erreurs et réétiquetons les images dans des rapports historiques importants; (2) décrivons les erreurs de description courantes et leurs causes en utilisant un langage familier aux chercheurs ayant une compréhension de base de la microscopie et des œufs de nématodes; (3) recommandons un nouveau cadre anatomique et terminologique hexalaminaire pour les coques des œufs de nématodes basé sur le cadre de C. elegans de 2012; et (4) recommandons de nouveaux termes non ambigus appropriés pour les œufs embryonnés/larvés régulièrement rencontrés par les spécialistes de nématodes en exercice pour remplacer les termes ambigus ou à restriction ontogénétique dans le cadre de C. elegans de 2012. Nous proposons également (5) une résolution des affirmations contradictoires de l'équipe C. elegans par rapport à la littérature classique concernant la couche 3, (6) étendons le cadre hexalaminaire de C. elegans pour inclure les bouchons polaires des trichinelloïdes, et (7) signalons de nouvelles découvertes concernant la structure de la coque des œufs des trichinelloïdes.


Asunto(s)
Nematodos , Terminología como Asunto , Cigoto , Animales , Caenorhabditis elegans/ultraestructura , Nematodos/ultraestructura , Cigoto/ultraestructura , Microscopía Electrónica de Transmisión , Microscopía Electrónica de Rastreo , Embrión no Mamífero/ultraestructura
12.
Parasite ; 30: 33, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37682122

RESUMEN

Based on light microscopical and scanning electron microscopical (SEM) examinations, two North American species of Spinitectus Fourment, 1884, S. acipenseri Choudhury & Dick, 1992 and S. micracanthus Christian, 1972 (Nematoda, Cystidicolidae) are redescribed from museum voucher specimens (S. acipenseri) and those newly collected from centrarchid and some other fishes in the Upper San Marcos River in Texas and the Santee River in South Carolina, USA. The first use of SEM to study S. acipenseri, a parasite of lake sturgeon Acipenser fulvescens Rafinesque (Acipenseridae) in Canada, made it possible to describe dorsal and ventral lips, amphids and sublabia, and the presence of a dorsal barb on the right spicule, which was confirmed to be the most characteristic feature of this species. The SEM study of S. micracanthus, a parasite mainly of centrarchids, enabled us to correctly determine the location of the excretory pore in relation to rings of cuticular spines in the male, and to describe the exact structure of the tip of the male tail, sublabia, phasmids and the presence of a median ventral protuberance on the male tail. Some taxonomic problems of North American species of Spinitectus are discussed. Filaria serrata Linton, 1901 is considered a junior synonym of S. oviflagellis Fourment, 1884. To date, there are 13 valid species of Spinitectus parasitising fishes in North America. Keys to species of Spinitectus-like nematodes from fishes in North American waters are provided.


Title: Redescriptions de Spinitectus acipenseri et S. micracanthus (Nematoda, Cystidicolidae), et notes sur la taxonomie des nématodes de type Spinitectus parasitant les poissons nord-américains. Abstract: Deux espèces nord-américaines de Spinitectus Fourment, 1884, S. acipenseri Choudhury & Dick, 1992 et S. micracanthus Christian, 1972 (Nematoda, Cystidicolidae) sont redécrites à partir de spécimens de musée et d'autres nouvellement collectés aux USA dans les rivières Upper San Marcos (Texas) and Santee (Caroline du Sud), avec l'aide de la microscopie optique et électronique à balayage (MEB). L'utilisation pour la première fois du MEB pour étudier S. acipenseri, un parasite de l'esturgeon Acipenser fulvescens Rafinesque (Acipenseridae) au Canada, a permis de décrire les lèvres dorsales and ventrales, les amphides et sublabia, ainsi que la barbe dorsale sur le spicule droit que nous confirmons être le critère le plus caractéristique de cette espèce. L'étude au MEB de S. micracanthus, un parasite principalement de centrarchides, nous a permis de déterminer correctement la place du pore excréteur en relation avec les couronnes d'épines cuticulaires chez le mâle, ainsi que de décrire la structure exacte de l'extrémité caudale du mâle, des sublabia, des phasmides et la présence d'une protubérance médiane et ventrale sur la queue du mâle. Des problèmes taxonomiques sur les espèces nord-américaines de Spinitectus sont discutés. Filaria serrata Linton, 1901 est considéré synonyme plus récent de S. oviflagellis Fourment, 1884. À ce jour, il y a 13 espèces valides de Spinitectus parasites de poissons en Amérique du Nord. Des clés des espèces des nématodes de type Spinitectus provenant des poissons des eaux nord-américaines sont fournies.


Asunto(s)
Gastrópodos , Spiruroidea , Masculino , Animales , Peces , Microscopía Electrónica de Rastreo , América del Norte
13.
Saudi J Biol Sci ; 29(12): 103430, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36106014

RESUMEN

From January 2017 - December 2019, 75 out of 850 (8.8 %) great hammerhead sharks from the Arabian Gulf had skin lesions of black irregular discolorations on the ventral surface of the head. The lesions consisted of pencil-like lineations often advancing forward by about 2 mm in back-and-forth looped scribbles often forming a relatively linear bands of about 5-7 cm wide. Similar lesions were also found in the blacktip reef shark from the same area within the same period, and consisted of straight to irregular black lines, extended indiscriminately across the skin of the sharks. Microscopic examination of the skin revealed the presence of dark-brown eggs exhibiting the spindle or ellipsoidal eggs characteristic of Huffmanela sp. The morphometrics of eggs from both hosts were similar (62.9-89.9 µm long and 29.3-56.1 µm wide). The eggshells were smooth with polar plugs protruding or not, with an abruptly truncated crown-like or shoulder-like collar surrounding the plug. The eggs were only found in the epidermal layer of the skin. Based on the unique morphometrics of the eggs, we report a new species, named: Huffmanela selachii n. sp.. This appears to be the first report of Huffmanela from either the great hammerhead shark or the blacktip reef shark, and the third reported Huffmanela in sharks from the Arabian Gulf. It is also one of few species reported from connecting waters of the greater Indian Ocean. This new finding contributes to our understanding of the diversity and ubiquity of Huffmanela sp. in marine creatures.

14.
Sci Data ; 7(1): 194, 2020 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-32572035

RESUMEN

Wildland fires have a multitude of ecological effects in forests, woodlands, and savannas across the globe. A major focus of past research has been on tree mortality from fire, as trees provide a vast range of biological services. We assembled a database of individual-tree records from prescribed fires and wildfires in the United States. The Fire and Tree Mortality (FTM) database includes records from 164,293 individual trees with records of fire injury (crown scorch, bole char, etc.), tree diameter, and either mortality or top-kill up to ten years post-fire. Data span 142 species and 62 genera, from 409 fires occurring from 1981-2016. Additional variables such as insect attack are included when available. The FTM database can be used to evaluate individual fire-caused mortality models for pre-fire planning and post-fire decision support, to develop improved models, and to explore general patterns of individual fire-induced tree death. The database can also be used to identify knowledge gaps that could be addressed in future research.


Asunto(s)
Incendios , Agricultura Forestal , Bosques , Árboles , Bases de Datos como Asunto , Estados Unidos
15.
J Econ Ageing ; 142019.
Artículo en Inglés | MEDLINE | ID: mdl-33088706

RESUMEN

This paper examines heterogeneity in time discounting among a representative sample of elderly Americans, as well as its role in explaining key economic behaviors at older ages. We show how older Americans evaluate simple (hypothetical) inter-temporal choices in which payments today are compared with payments in the future. Using the indicators derived from this measure, we then demonstrate that differences in discounting patterns are associated with characteristics of particular importance in elderly populations. For example, cognitive deficits are associated with greater impatience, whereas bequest motives are associated with less impatience. We then relate our discounting measure to key economic outcomes and find that impatience is associated with lower wealth, fewer investments in health, and less planning for end of life care.

16.
Int J Parasitol Parasites Wildl ; 9: 266-273, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31245277

RESUMEN

Some pouting caught off the Atlantic coast of Portugal are discarded as unmarketable due to a dark discolouration of the skin and muscle. This study investigates the cause of this condition, describes the new parasite species responsible, and highlights the importance of educating those in charge of premarket inspection of food fish in order to reduce likelihood that consumers will eat infected fish. Macroscopically, infected fish showed considerable heterogeneity in darkening of the skin and hypaxial and epaxial muscles. Microscopical observation revealed bipolar nematode eggs in varying stages of development arranged in a linear pattern along muscle fibers. Histopathology confirmed the presence of eggs of a nematode of the genus Huffmanela Moravec, 1987 as the cause of muscle darkening and established a relationship between infection intensity and consequent darkened appearance of the tissues. The eggs are oval or barrel-shaped, with a smooth surface and polar plugs at opposite ends. The thin outer vitelline membrane is smooth and lacks ornamentation. Under light microscopy, the main eggshell of older eggs exhibits the outermost delicate and smooth vitelline membrane, and a thicker layer, correspondent to chitinous and chondroitin proteoglycan layers. Scanning electron microscopy of eggs confirmed light microscopic studies, namely the presence of a smooth vitelline membrane surrounding the egg. Microscopic and ultrastructural characteristics of eggs, and a new host family in a new geographic area, all suggest that a new species, herein named Huffmanela lusitana sp. n. is involved.

17.
Diabetes Care ; 41(11): 2346-2352, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30213882

RESUMEN

OBJECTIVE: Healthy pancreatic ß-cells secrete the hormones insulin and amylin in a fixed ratio. Both hormones are lacking in type 1 diabetes, and postprandial glucose control using insulin therapy alone is difficult. This study tested the pharmacodynamic effects of the amylin analog pramlintide and insulin delivered in a fixed ratio over a 24-h period. RESEARCH DESIGN AND METHODS: Patients with type 1 diabetes were stabilized on insulin pump therapy with insulin lispro before a randomized, single-masked, two-way crossover, 24-h inpatient study in which regular human insulin was administered with pramlintide or placebo using separate infusion pumps in a fixed ratio (9 µg/unit). Meal content and timing and patient-specific insulin doses were the same with each treatment. The primary outcome measure was change in mean glucose by continuous glucose monitoring (CGM). Profiles of laboratory-measured glucose, insulin, glucagon, and triglycerides were also compared. RESULTS: Mean 24-h glucose measured by CGM was lower with pramlintide versus placebo (8.5 vs. 9.7 mmol/L, respectively; P = 0.012) due to a marked reduction of postprandial increments. Glycemic variability was reduced, and postprandial glucagon and triglycerides were also lower with pramlintide versus placebo. Gastrointestinal side effects were more frequent during use of pramlintide; no major hypoglycemic events occurred with pramlintide or placebo. CONCLUSIONS: Coadministration of fixed-ratio pramlintide and regular human insulin for 24 h improved postprandial hyperglycemia and glycemic variability in patients with type 1 diabetes. Longer studies including dose titration under daily conditions are needed to determine whether this regimen could provide long-term improvement of glycemic control.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hiperglucemia/prevención & control , Hipoglucemiantes/administración & dosificación , Insulina Regular Humana/administración & dosificación , Polipéptido Amiloide de los Islotes Pancreáticos/administración & dosificación , Adolescente , Adulto , Anciano , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Automonitorización de la Glucosa Sanguínea , Estudios Cruzados , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/complicaciones , Esquema de Medicación , Combinación de Medicamentos , Femenino , Humanos , Hiperglucemia/sangre , Hipoglucemiantes/efectos adversos , Sistemas de Infusión de Insulina , Insulina Regular Humana/efectos adversos , Polipéptido Amiloide de los Islotes Pancreáticos/efectos adversos , Masculino , Comidas , Persona de Mediana Edad , Método Simple Ciego , Adulto Joven
18.
Nutr Diabetes ; 8(1): 33, 2018 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-29795365

RESUMEN

BACKGROUND/OBJECTIVE: Financial incentives can improve initial weight loss; we examined whether financial incentives can improve weight loss maintenance. SUBJECTS/METHODS: Participants aged 30-80 years who lost at least 5 kg during the first 4-6 months in a nationally available commercial weight loss program were recruited via the internet into a three-arm randomized trial of two types of financial incentives versus active control during months 1-6 (Phase I) followed by passive monitoring during months 7-12 (Phase II). Interventions were daily self-weighing and text messaging feedback alone (control) or combined with a lottery-based incentive or a direct incentive. The primary outcome was weight change 6 months after initial weight loss. Secondary outcomes included weight change 12 months after initial weight loss (6 months after cessation of maintenance intervention), and self-reported physical activity and eating behaviors. RESULTS: Of 191 participants randomized, the mean age was 49.0 (SD = 10.5) years and weight loss prior to randomization was 11.4 (4.7) kg; 92% were women and 89% were White. Mean weight changes during the next 6 months (Phase I) were: lottery -3.0 (5.8) kg; direct -2.8 (5.8) kg; and control -1.4 (5.8) kg (all pairwise comparisons p > 0.1). Weight changes through the end of 12 months post-weight loss (Phase II) were: lottery -1.8 (10.5) kg; direct -0.7 (10.7) kg; and control -0.3 (9.4) kg (all pairwise comparisons p > 0.1). The percentages of participants who maintained their weight loss (defined as gaining ≤1.36 kg) were: lottery 79%, direct 76%, and control 67% at 6 months and lottery 66%, direct 62%, and control 59% at 12 months (all pairwise comparisons p > 0.1). At 6 and 12 months after initial weight loss, changes in self-reported physical activity or eating behaviors did not differ across arms. CONCLUSIONS: Compared with the active control of daily texting based on daily home weighing, lottery-based and direct monetary incentives provided no additional benefit for weight loss maintenance.


Asunto(s)
Ejercicio Físico , Conducta Alimentaria , Conductas Relacionadas con la Salud , Motivación , Pérdida de Peso , Programas de Reducción de Peso , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Internet , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
19.
Biochim Biophys Acta ; 1760(6): 907-12, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16632204

RESUMEN

Human Wilson protein functions in the secretory pathway to insert copper ultimately into the multicopper oxidase ceruloplasmin and also plays a role in the excretion of excess copper to the bile. This copper-transporting P-type ATPase possesses six N-terminal cytosolic copper-binding domains contained within an approximately 72 amino acid consensus motif and the first four of these domains, denoted WLN1-4, are implicated in copper acquisition from the metallochaperone HAH1, whereas the domains closest to the membrane portion of the enzyme, WLN5-6, are essential for copper transport across the membrane. In order to test our hypothesis that copper transfer occurs between domains in the N-terminus of Wilson protein, we expressed and purified to homogeneity copper-binding domains 1, 3, 4, 5-6, and 6, denoted by WLN1, WLN3, WLN4, WLN5-6, and WLN6, respectively. Since we determined WLN1 and WLN4 to have the highest and lowest isoelectric points (6.77 and 3.85, respectively) and thus are readily separated via ion exchange chromatography, we developed a copper transfer assay between these domains. We anaerobically incubated either Cu(I)-WLN1 with apo-WLN4 or apo-WLN1 with Cu(I)-WLN4, then separated these domains and quantified the amount of copper that migrates from one domain to another by ICP-MS. Regardless of whether we start with Cu(I)-WLN1 or Cu(I)-WLN4 as the initial copper donor, we demonstrate facile copper transfer between WLN1 and WLN4, thereby demonstrating the feasibility of copper transfer between these domains in vivo.


Asunto(s)
Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/metabolismo , Proteínas de Transporte de Catión/química , Proteínas de Transporte de Catión/metabolismo , Cobre/metabolismo , Transporte Biológico , ATPasas Transportadoras de Cobre , Humanos , Punto Isoeléctrico , Unión Proteica , Estructura Terciaria de Proteína
20.
Ecol Evol ; 7(23): 10278-10288, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29238554

RESUMEN

Geographic isolation is known to contribute to divergent evolution, resulting in unique phenotypes. Oftentimes morphologically distinct populations are found to be interfertile while reproductive isolation is found to exist within nominal morphological species revealing the existence of cryptic species. These disparities can be difficult to predict or explain especially when they do not reflect an inferred history of common ancestry which suggests that environmental factors affect the nature of ecological divergence. A series of laboratory experiments and observational studies were used to address what role biogeographic factors may play in the ecological divergence of Hyalella amphipods. It was found that geographic isolation plays a key role in the evolution of reproductive isolation and divergent morphology and that divergence cannot be explained by molecular genetic variation.

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