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1.
Jt Comm J Qual Patient Saf ; 49(11): 592-598, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37612179

RESUMEN

BACKGROUND: Capacity challenges at quaternary hospitals cause delays or denials in patient transfers from community hospitals that can compromise quality and safety. Repatriation is an innovative approach to increase capacity at the quaternary hospital by transferring a patient back to their originating community hospital after the quaternary portion of their care is completed. METHODS: A repatriation program was implemented at a large quaternary care teaching hospital over a one-year period (2020 to 2021). The authors characterized the rate of successful repatriation and associated patient characteristics, determined the impact on quaternary hospital capacity in terms of bed days saved, and estimated the resultant number of backfilled admissions that could be accommodated. The research team also monitored the rate of readmissions for repatriations back to the quaternary hospital. RESULTS: Overall, 215 repatriations were attempted, and 103 (47.5%) were successful. The most common diagnoses were sepsis (13, 12.6%), stroke (12, 11.7%), intracranial bleed (10, 9.7%), gastrointestinal perforation/obstruction (9, 8.7%), and trauma (9, 8.7%). The median length of stay at the quaternary hospital was 13 days (interquartile range [IQR] 7-20) and 12 days (IQR 4-26) at the community hospital. There were 2,842 bed days saved at the quaternary hospital, with a backfill opportunity of 431 admissions. The readmission rate to the quaternary hospital was 1.9%. CONCLUSION: By dynamically matching patient need with hospital capability at different phases of the patient's care, Repatriation can save bed days at the quaternary hospital, creating capacity to improve access for patients needing timely transfer. The low observed readmission rate suggests that repatriation is safe.


Asunto(s)
Hospitales Comunitarios , Accidente Cerebrovascular , Humanos , Hospitalización , Transferencia de Pacientes , Readmisión del Paciente , Tiempo de Internación
2.
Health Care Manag Sci ; 26(3): 501-515, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37294365

RESUMEN

Early bed assignments of elective surgical patients can be a useful planning tool for hospital staff; they provide certainty in patient placement and allow nursing staff to prepare for patients' arrivals to the unit. However, given the variability in the surgical schedule, they can also result in timing mismatches-beds remain empty while their assigned patients are still in surgery, while other ready-to-move patients are waiting for their beds to become available. In this study, we used data from four surgical units in a large academic medical center to build a discrete-event simulation with which we show how a Just-In-Time (JIT) bed assignment, in which ready-to-move patients are assigned to ready-beds, would decrease bed idle time and increase access to general care beds for all surgical patients. Additionally, our simulation demonstrates the potential synergistic effects of combining the JIT assignment policy with a strategy that co-locates short-stay surgical patients out of inpatient beds, increasing the bed supply. The simulation results motivated hospital leadership to implement both strategies across these four surgical inpatient units in early 2017. In the several months post-implementation, the average patient wait time decreased 25.0% overall, driven by decreases of 32.9% for ED-to-floor transfers (from 3.66 to 2.45 hours on average) and 37.4% for PACU-to-floor transfers (from 2.36 to 1.48 hours), the two major sources of admissions to the surgical floors, without adding additional capacity.


Asunto(s)
Pacientes Internos , Listas de Espera , Humanos , Simulación por Computador , Servicio de Urgencia en Hospital , Hospitalización , Hospitales
3.
Ecology ; 104(5): e4036, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36944538

RESUMEN

Climate change models often assume similar responses to temperatures across the range of a species, but local adaptation or phenotypic plasticity can lead plants and animals to respond differently to temperature in different parts of their range. To date, there have been few tests of this assumption at the scale of continents, so it is unclear if this is a large-scale problem. Here, we examined the assumption that insect taxa show similar responses to temperature at 96 sites in grassy habitats across North America. We sampled insects with Malaise traps during 2019-2021 (N = 1041 samples) and examined the biomass of insects in relation to temperature and time of season. Our samples mostly contained Diptera (33%), Lepidoptera (19%), Hymenoptera (18%), and Coleoptera (10%). We found strong regional differences in the phenology of insects and their response to temperature, even within the same taxonomic group, habitat type, and time of season. For example, the biomass of nematoceran flies increased across the season in the central part of the continent, but it only showed a small increase in the Northeast and a seasonal decline in the Southeast and West. At a smaller scale, insect biomass at different traps operating on the same days was correlated up to ~75 km apart. Large-scale geographic and phenological variation in insect biomass and abundance has not been studied well, and it is a major source of controversy in previous analyses of insect declines that have aggregated studies from different locations and time periods. Our study illustrates that large-scale predictions about changes in insect populations, and their causes, will need to incorporate regional and taxonomic differences in the response to temperature.


Asunto(s)
Insectos , Lepidópteros , Animales , Temperatura , Insectos/fisiología , Ecosistema , Aclimatación
4.
J Hosp Med ; 18(7): 568-575, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36788630

RESUMEN

BACKGROUND: Increased hospital admissions due to COVID-19 place a disproportionate strain on inpatient general medicine service (GMS) capacity compared to other services. OBJECTIVE: To study the impact on capacity and safety of a hospital-wide policy to redistribute admissions from GMS to non-GMS based on admitting diagnosis during surge periods. DESIGN, SETTING, AND PARTICIPANTS: Retrospective case-controlled study at a large teaching hospital. The intervention included adult patients admitted to general care wards during two surge periods (January-February 2021 and 2022) whose admission diagnosis was impacted by the policy. The control cohort included admissions during a matched number of days preceding the intervention. MAIN OUTCOMES AND MEASURES: Capacity measures included average daily admissions and hospital census occupied on GMS. Safety measures included length of stay (LOS) and adverse outcomes (death, rapid response, floor-to-intensive care unit transfer, and 30-day readmission). RESULTS: In the control cohort, there were 365 encounters with 299 (81.9%) GMS admissions and 66 (18.1%) non-GMS versus the intervention with 384 encounters, including 94 (24.5%) GMS admissions and 290 (75.5%) non-GMS (p < .001). The average GMS census decreased from 17.9 and 21.5 during control periods to 5.5 and 8.5 during intervention periods. An interrupted time series analysis confirmed a decrease in GMS daily admissions (p < .001) and average daily hospital census (p = .014; p < .001). There were no significant differences in LOS (5.9 vs. 5.9 days, p = .059) or adverse outcomes (53, 14.5% vs. 63, 16.4%; p = .482). CONCLUSION: Admission redistribution based on diagnosis is a safe lever to reduce capacity strain on GMS during COVID-19 surges.


Asunto(s)
COVID-19 , Admisión del Paciente , Adulto , Humanos , Estudios Retrospectivos , COVID-19/epidemiología , COVID-19/terapia , Hospitalización , Tiempo de Internación , Hospitales de Enseñanza
5.
Jt Comm J Qual Patient Saf ; 49(4): 181-188, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36476954

RESUMEN

BACKGROUND: Hospitals have sought to increase pre-noon discharges to improve capacity, although evidence is mixed on the impact of these initiatives. Past interventions have not quantified the daily gap between morning bed supply and demand. The authors quantified this gap and applied the pre-noon data to target a pre-noon discharge initiative. METHODS: The study was conducted at a large hospital and included adult and pediatric medical/surgical wards. The researchers calculated the difference between the average cumulative bed requests and transfers in for each hour of the day in 2018, the year prior to the intervention. In 2019 an intervention on six adult general medical and two surgical wards was implemented. Eight intervention and 14 nonintervention wards were compared to determine the change in average cumulative pre-noon discharges. The change in average hospital length of stay (LOS) and 30-day readmissions was also calculated. RESULTS: The average daily cumulative gap by noon between bed supply and demand across all general care wards was 32.1 beds (per ward average, 1.3 beds). On intervention wards, mean pre-noon discharges increased from 4.7 to 6.7 (p < 0.0000) compared with the nonintervention wards 14.0 vs. 14.6 (p = 0.19877). On intervention wards, average LOS decreased from 6.9 to 6.4 days (p < 0.001) and readmission rates were 14.3% vs 13.9% (p = 0.3490). CONCLUSION: The gap between daily hospital bed supply and demand can be quantified and applied to create pre-noon discharge targets. In an intervention using these targets, researchers observed an increase in morning discharges, a decrease in LOS, and no significant change in readmissions.


Asunto(s)
Alta del Paciente , Readmisión del Paciente , Adulto , Humanos , Niño , Tiempo de Internación , Equipos y Suministros de Hospitales , Hospitales
6.
Inorg Chem ; 61(39): 15325-15334, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36121917

RESUMEN

Double hydrogen atom abstraction from (TMP)OsII(NH3)2 (TMP = tetramesitylporphyrin) with phenoxyl or nitroxyl radicals leads to (TMP)OsIV(NH2)2. This unusual bis(amide) complex is diamagnetic and displays an N-H resonance at 12.0 ppm in its 1H NMR spectrum. 1H-15N correlation experiments identified a 15N NMR spectroscopic resonance signal at -267 ppm. Experimental reactivity studies and density functional theory calculations support relatively weak N-H bonds of 73.3 kcal/mol for (TMP)OsII(NH3)2 and 74.2 kcal/mol for (TMP)OsIII(NH3)(NH2). Cyclic voltammetry experiments provide an estimate of the pKa of [(TMP)OsIII(NH3)2]+. In the presence of Barton's base, a current enhancement is observed at the Os(III/II) couple, consistent with an ECE event. Spectroscopic experiments confirmed (TMP)OsIV(NH2)2 as the product of bulk electrolysis. Double hydrogen atom abstraction is influenced by π donation from the amides of (TMP)OsIV(NH2)2 into the d orbitals of the Os center, favoring the formation of (TMP)OsIV(NH2)2 over N-N coupling. This π donation leads to a Jahn-Teller distortion that splits the energy levels of the dxz and dyz orbitals of Os, results in a low-spin electron configuration, and leads to minimal aminyl character on the N atoms, rendering (TMP)OsIV(NH2)2 unreactive toward amide-amide coupling.

7.
Am J Emerg Med ; 60: 29-33, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35882180

RESUMEN

BACKGROUND: Emergency department boarding and crowding lead to worse patient outcomes and patient satisfaction. OBJECTIVE: We describe the implementation of a program to transfer patients requiring medical admission from an academic emergency department to a community hospital's medical floor and analyze its effects on patient outcomes. METHODS: A prospective cohort study was performed. Data was collected on patient flow through the transfer program. Patient characteristics, boarding time in the emergency department, and hospital-based outcome measures were compared between patients in the transfer program who were successfully transferred to the community hospital and patients who were admitted to the academic medical center. RESULTS: 79 patients were successfully transferred to the community hospital between November 23, 2020 and August 5, 2021, resulting in 279 bed days in the community hospital. Successfully transferred patients experienced a statistically shorter ED boarding time (5.7 vs. 10.9 h, p < 0.0001), ED length of stay (10.5 vs 16.1 h, p < 0.0001), and hospital length of stay (3.5 vs 5.7 days, p < 0.0001) compared to patients initially referred to the transfer program who were admitted to the academic medical center. There were no reported adverse events during transfer, upgrades to the ICU within 24 h of admission, or inpatient deaths for patients who were transferred. CONCLUSION: We implemented an academic emergency department to partner community hospital transfer program that safely level-loads medical patients in a healthcare system.


Asunto(s)
Hospitales Comunitarios , Admisión del Paciente , Servicio de Urgencia en Hospital , Humanos , Tiempo de Internación , Estudios Prospectivos , Estudios Retrospectivos
8.
J Anim Ecol ; 91(8): 1707-1718, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35521665

RESUMEN

Genes of the major histocompatibility complex (MHC) encode antigen-binding molecules and are an integral part of the acquired immune response of vertebrates. In general, high individual MHC diversity is expected to increase fitness by broadening the spectrum of pathogens recognized by the immune system, in accordance with the heterozygote advantage mechanism. On the other hand, the optimality hypothesis assumes that individuals with optimal (intermediate), rather than maximum, diversity of the MHC will achieve the highest fitness because of inherent costs associated with expressing diverse MHC alleles. Here, we tested for associations between individual diversity of the MHC class I and class II genes (binding antigens of intra- and extracellular pathogens respectively) and a range of fitness-related traits (condition, ornament expression and reproduction) in an urban population of the Eurasian coot Fulica atra. Contrary to our expectation, we found that high within-individual allelic diversity of MHC genes (both class I and II) was associated with poorer condition (lower blood haemoglobin concentrations), weaker expression of the putative ornament (smaller frontal shield), later onset of breeding and smaller clutches. An analysis of functional MHC allele clusters (supertypes) provided further support for negative associations of MHC diversity with phenotypic quality and reproductive performance, but most of these relationships could not be explained by the presence of specific maladaptive supertypes. Finally, we found little empirical support for the optimality hypothesis in the Eurasian coot. Our results suggest that the costs of high MHC diversity outweighed any benefits associated with broad MHC repertoire, which could be driven by depauperate pathogen diversity in an urban landscape. To the best of our knowledge, this is one of the first studies providing consistent evidence for negative associations of MHC diversity with a range of fitness-related traits in a natural avian population.


Asunto(s)
Variación Genética , Selección Genética , Animales , Animales Salvajes , Aves/genética , Complejo Mayor de Histocompatibilidad/genética , Reproducción
9.
Clin Transl Gastroenterol ; 13(7): e00482, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35347098

RESUMEN

INTRODUCTION: Delays in inpatient colonoscopy are commonly caused by inadequate bowel preparation and result in increased hospital length of stay (LOS) and healthcare costs. Low-volume bowel preparation (LV-BP; sodium sulfate, potassium sulfate, and magnesium sulfate ) has been shown to improve outpatient bowel preparation quality compared with standard high-volume bowel preparations (HV-BP; polyethylene glycol ). However, its efficacy in hospitalized patients has not been well-studied. We assessed the impact of LV-BP on time to colonoscopy, hospital LOS, and bowel preparation quality among inpatients. METHODS: We performed a propensity score-matched analysis of adult inpatients undergoing colonoscopy who received either LV-BP or HV-BP before colonoscopy at a quaternary academic medical center. Multivariate regression models with feature selection were developed to assess the association between LV-BP and study outcomes. RESULTS: Among 1,807 inpatients included in this study, 293 and 1,514 patients received LV-BP and HV-BP, respectively. Among the propensity score-matched population, LV-BP was associated with a shorter time to colonoscopy (ß: -0.43 [95% confidence interval: -0.56 to -0.30]) while having similar odds of adequate preparation (odds ratio: 1.02 [95% confidence interval: 0.71-1.46]; P = 0.92). LV-BP was also significantly associated with decreased hospital LOS among older patients (age ≥ 75 years), patients with chronic kidney disease, and patients who were hospitalized with gastrointestinal bleeding. DISCUSSION: LV-BP is associated with decreased time to colonoscopy in hospitalized patients. Older inpatients, inpatients with chronic kidney disease, and inpatients with gastrointestinal bleeding may particularly benefit from LV-BP. Prospective studies are needed to further establish the role of LV-BP for inpatient colonoscopies.


Asunto(s)
Catárticos , Insuficiencia Renal Crónica , Adulto , Anciano , Colonoscopía/efectos adversos , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Humanos , Pacientes Internos
10.
Front Genet ; 13: 823686, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35251132

RESUMEN

The Major Histocompatibility Complex (MHC) is a hyper-polymorphic genomic region, which forms a part of the vertebrate adaptive immune system and is crucial for intra- and extra-cellular pathogen recognition (MHC-I and MHC-IIA/B, respectively). Although recent advancements in high-throughput sequencing methods sparked research on the MHC in non-model species, the evolutionary history of MHC gene structure is still poorly understood in birds. Here, to explore macroevolutionary patterns in the avian MHC architecture, we retrieved contigs with antigen-presenting MHC and MHC-related genes from available genomes based on third-generation sequencing. We identified: 1) an ancestral avian MHC architecture with compact size and tight linkage between MHC-I, MHC-IIA/IIB and MHC-related genes; 2) three major patterns of MHC-IIA/IIB unit organization in different avian lineages; and 3) lineage-specific gene translocation events (e.g., separation of the antigen-processing TAP genes from the MHC-I region in passerines), and 4) the presence of a single MHC-IIA gene copy in most taxa, showing evidence of strong purifying selection (low dN/dS ratio and low number of positively selected sites). Our study reveals long-term macroevolutionary patterns in the avian MHC architecture and provides the first evidence of important transitions in the genomic arrangement of the MHC region over the last 100 million years of bird evolution.

11.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35165176

RESUMEN

Extravagant ornaments are thought to signal male quality to females choosing mates, but the evidence linking ornament size to male quality is controversial, particularly in cases in which females prefer different ornaments in different populations. Here, we use whole-genome sequencing and transcriptomics to determine the genetic basis of ornament size in two populations of a widespread warbler, the common yellowthroat (Geothlypis trichas). Within a single subspecies, females in a Wisconsin population prefer males with larger black masks as mates, while females in a New York population prefer males with larger yellow bibs. Despite being produced by different pigments in different patches on the body, the size of the ornament preferred by females in each population was linked to numerous genes that function in many of the same core aspects of male quality (e.g., immunity and oxidative balance). These relationships confirm recent hypotheses linking the signaling function of ornaments to male quality. Furthermore, the parallelism in signaling function provides the flexibility for different types of ornaments to be used as signals of similar aspects of male quality. This could facilitate switches in female preference for different ornaments, a potentially important step in the early stages of divergence among populations.


Asunto(s)
Conducta Sexual Animal/fisiología , Pájaros Cantores/genética , Pájaros Cantores/metabolismo , Animales , Carotenoides/metabolismo , Femenino , Masculino , Melaninas/metabolismo , Passeriformes , Pigmentación/fisiología , Caracteres Sexuales
12.
Disaster Med Public Health Prep ; 16(5): 2182-2184, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-33588971

RESUMEN

Before coronavirus disease 2019 (COVID-19), few hospitals had fully tested emergency surge plans. Uncertainty in the timing and degree of surge complicates planning efforts, putting hospitals at risk of being overwhelmed. Many lack access to hospital-specific, data-driven projections of future patient demand to guide operational planning. Our hospital experienced one of the largest surges in New England. We developed statistical models to project hospitalizations during the first wave of the pandemic. We describe how we used these models to meet key planning objectives. To build the models successfully, we emphasize the criticality of having a team that combines data scientists with frontline operational and clinical leadership. While modeling was a cornerstone of our response, models currently available to most hospitals are built outside of their institution and are difficult to translate to their environment for operational planning. Creating data-driven, hospital-specific, and operationally relevant surge targets and activation triggers should be a major objective of all health systems.


Asunto(s)
COVID-19 , Defensa Civil , Planificación en Desastres , Humanos , COVID-19/epidemiología , Hospitales , Pandemias/prevención & control , Capacidad de Reacción
13.
Environ Sci Pollut Res Int ; 29(5): 7170-7184, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34472026

RESUMEN

Biochar compound fertilisers (BCFs) are an emerging technology that combine biochar with nutrients, clays and minerals and can be formulated to address specific issues in soil-plant systems. However, knowledge of BCF performance over consecutive crops and without re-application is limited. This study aims to assess the residual effect of organic BCFs soil-plant nutrient cycling 2 years after application and without additional fertiliser inputs. We applied BCFs and biochar with organic fertiliser amendments and established a crop of ginger and a second crop of turmeric (Curcuma longa) without re-application or additional fertilisation. All treatment formulations included bamboo-biochar and organic fertiliser amendments; however, two novel BCFs were formulated to promote agronomic response in an intensive cropping system. We report here on the effect of treatments on soil and plant macronutrient and micronutrient cycling and turmeric growth, biomass and yield at harvest. Both BCFs (enriched (10 t ha-1) and organo-mineral biochar (8.6 t ha-1) increased foliar K (+155% and +120%) and decreased foliar Mg (-20% and -19%) concentration compared with all other treatments, suggesting antagonism between K and Mg. Plants were limited for K, P and B at harvest but not N, Ca or Mg. Foliar K was dependent on the biochar formulation rather than the rate of application. Biochar-clay aggregates increased K retention and cycling in the soil solution 2 years after application. Clay blended BCFs reduced K limitation in turmeric compared to biochar co-applied with organic amendments, suggesting these blends can be used to manage organic K nutrition. All formulations and rates of biochar increased leaf biomass and shoot-to-root ratio. Novel BCFs should be considered as an alternative to co-applying biochar with organic fertiliser amendments to decrease application rates and increase economic feasibility for farmers. Applying BCFs without re-application or supplementary fertiliser did not provide sufficient K or P reserves in the second year for consecutive cropping. Therefore, supplementary fertilisation is recommended to avoid nutrient deficiency and reduced yield for consecutive organic rhizome crops.


Asunto(s)
Carbón Orgánico , Fertilizantes , Fertilizantes/análisis , Potasio , Suelo
14.
Am J Med Qual ; 36(5): 368-370, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34225276

RESUMEN

COVID-19 continues to challenge bed capacity and the ability of hospitals to provide quality care for patients around the country. However, the COVID-19 pandemic at a given point in time does not impact all hospitals equally-even within a single healthcare system, one hospital may be caring for patients in the hallways, while another has available inpatient beds. Here, we demonstrate a program to level-load COVID-19 patients between 2 academic medical centers in a healthcare system by transferring patients at the time of admission from the emergency department of one institution directly to an inpatient bed of the other institution. Over 42 days, 50 patients were transferred which saved 432 bed-days at the home academic medical center without any adverse events during transfer or upgrades to the ICU within the first 24 hours of admission. Programs like this can expand a healthcare system's ability to allocate personnel and resources efficiently for patients and maximize the quality of care delivered even during a pandemic.


Asunto(s)
COVID-19 , Servicio de Urgencia en Hospital , Pandemias , Transferencia de Pacientes , Centros Médicos Académicos , Atención a la Salud , Humanos , Unidades de Cuidados Intensivos
15.
Immunogenetics ; 73(5): 395-404, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34195858

RESUMEN

Ducks (Anatidae) are often vectors for the spread of pathogens because of their long-distance migrations. These migrations also expose ducks to a wide variety of pathogens in their wintering and breeding grounds, and, as a consequence, we might expect strong selection on their immune genes. Here, we studied exons 2 and 3 of the MHC class I in four species of Anas ducks (A. platyrhynchos, A. poecilorhyncha, A. formosa, and A. querquedula) using Illumina-sequencing. Both exons 2 and 3 code for the peptide-binding region of class I molecules; however, most previous studies of birds have only focused on exon 3. Here, we found stronger positive selection on exon 2 than exon 3, as indicated by more species with dN/dS > 1 and higher Wu-Kabat values. There was little evidence that divergence time influenced polymorphism, the numbers of identical alleles (partial α1 or α2 regions) among four Anas, or selection, suggesting that these widespread species might share similar levels of selection from pathogens. The high similarity of allele numbers, positively selected sites (PSS), conserved motifs, and variable protein sites (VPS) supported the persistence of trans-species polymorphism in Anas for at least 10 million years. Our study revealed exon 2 as a relatively unexplored source of variation in avian MHC class I, which should be considered in future studies.


Asunto(s)
Patos/genética , Genes MHC Clase I , Polimorfismo Genético , Alelos , Animales , Exones , Filogenia , Selección Genética
16.
BMC Ecol Evol ; 21(1): 80, 2021 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-33964878

RESUMEN

BACKGROUND: The Major Histocompatibility Complex (MHC) codes for the key vertebrate immune receptors responsible for pathogen recognition. Foreign antigens are recognized via their compatibility to hyper-variable region of the peptide-binding groove (PBR), which consists of two separate protein domains. Specifically, the PBR of the MHC class I receptors, which recognize intra-cellular pathogens, has two α domains encoded by exon 2 (α1) and exon 3 (α2) of the same gene. Most research on avian MHC class I polymorphism has traditionally focused exclusively on exon 3 and comparisons of selection between the two domains have been hampered by the scarcity of molecular data for exon 2. Thus, it is not clear whether the two domains vary in their specificity towards different antigens and whether they are subject to different selective pressure. RESULTS: Here, we took advantage of rapidly accumulating genomic resources to test for the differences in selection patterns between both MHC class I domains of the peptide-binding groove in birds. For this purpose, we compiled a dataset of MHC class I exon 2 and 3 sequences for 120 avian species from 46 families. Our phylogenetically-robust approach provided strong evidence for highly consistent levels of selection on the α1 and α2 domains. There were strong correlations in all selection measures (number of positively/negatively selected residues and dN/dS ratios) between both PBR exons. Similar positive associations were found for the level of amino acid polymorphism across the two domains. CONCLUSIONS: We conclude that the strength of selection and the level of polymorphism are highly consistent between both peptide-binding domains (α1 and α2) of the avian MHC class I.


Asunto(s)
Aves , Polimorfismo Genético , Animales , Aves/genética , Humanos , Complejo Mayor de Histocompatibilidad , Péptidos , Filogenia
17.
J Anim Ecol ; 90(10): 2325-2335, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34028816

RESUMEN

Optimal size of social groups may vary between individuals, depending on their phenotypic traits, such as dominance status, age or personality. Larger social groups often enhance transmission rates of pathogens and should be avoided by individuals with poor immune defences. In contrast, more immunocompetent individuals are expected to take advantage of larger group sizes (e.g. better protection, information transfer) with smaller extra costs from pathogen or parasite pressure. Here, we hypothesized that immunocompetence may be a key determinant of group size choice and tested this hypothesis in a colonial waterbird, the common tern Sterna hirundo. We used a unique experimental framework, where formation of breeding colonies of different sizes was induced under uniform environmental conditions. For this purpose, different-size patches of attractive nesting substrate (artificial floating rafts) were provided at a single site with limited availability of natural nesting habitat. Colony size was identified as the only significant predictor of both innate (natural antibody-mediated complement activation) and adaptive (immunoglobulin concentrations) immunological traits in the common terns, as more immunocompetent birds settled in larger experimental colonies. In contrast, we found no significant associations between colony size and genetic diversity of key pathogen-recognition receptors, toll-like receptors (TLRs) and the Major Histocompatibility Complex (MHC) or genome-wide heterozygosity. We conclude that settlement decisions may be flexible within individuals and, thus, are likely to be primarily determined by the current immunological status, rather than fixed immunogenetic traits. Our study sheds new light on the complex interface between immunity and sociality in animals.


Asunto(s)
Aves , Charadriiformes , Animales , Ecosistema , Conducta Social
18.
Curr Med Res Opin ; 37(4): 531-534, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33565898

RESUMEN

OBJECTIVE: Patients with obstructive sleep apnea (OSA) are at risk for adverse events when moderate sedation is administered by nurse protocols (NAMS) under the guidance of non-anesthesiologists. An algorithm was applied for the appropriate section of patients to receive NAMS and the application of continuous positive airway pressure (CPAP). METHODS: An algorithm was developed for patients with OSA who were scheduled for gastroenterology, radiology, and cardiology procedures using NAMS. Those with normal airways and without contraindications for NAMS were classified as CPAP-independent (CPAP-I; not routinely used) or CPAP-dependent (CPAP-D; always used). CPAP machines were brought in by CPAP-D patients or supplied by the hospital and set at a patient's routine setting or 10 cm H2O if not known. CPAP-D patients for procedures for which CPAP could not be applied were done under anesthesia care. We retrospectively examined this program for the 2008-2018 period. RESULTS: Since the inception of this protocol in 2008, 803 patients with OSA safely underwent procedures using either personal CPAP or CPAP provided by the hospital. CONCLUSIONS: Patients with OSA can safely have NAMS for procedures when CPAP is applied based on a protocol that considers airway evaluation, the procedure, and whether there is dependence upon CPAP.


Asunto(s)
Anestesia , Apnea Obstructiva del Sueño , Algoritmos , Anestesia/efectos adversos , Presión de las Vías Aéreas Positiva Contínua , Humanos , Estudios Retrospectivos , Apnea Obstructiva del Sueño/terapia
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