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1.
J Frailty Aging ; 13(2): 91-97, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38616364

RESUMO

BACKGROUND: Sarcopenia and frailty are often used interchangeably in clinical practice yet represent two distinct conditions and require different therapeutic approaches. The literature regarding the co-occurrence of both conditions in older patients is scarce as most studies have investigated the prevalence of sarcopenia and frailty separately. OBJECTIVES: We aim to evaluate the prevalence and co-occurrence of sarcopenia and frailty in a large sample of acutely admitted older medical patients. DESIGN: Secondary analyses using cross-sectional data from the Copenhagen PROTECT study. SETTING: Patients were included from the acute medical ward at Copenhagen University Hospital, Bispebjerg and Frederiksberg, Copenhagen, Denmark, between November 2019 and November 2021. PARTICIPANTS: Acutely admitted older medical patients (≥65 years). MEASUREMENTS: Handgrip strength (HGS) was investigated using a handheld dynamometer. Lean mass (SMI) was investigated using direct-segmental multifrequency bioelectrical impedance analyses (DSM-BIA). Low HGS, low SMI, and sarcopenia were defined according to the recent definitions from the European Working Group on Sarcopenia in Older People (EWGSOP2). The Clinical Frailty Scale (CFS) was used to evaluate frailty, with a value > 5 indicating the presence of frailty. Patients were enrolled and tested within 24 hours of admission. RESULTS: This study included 638 patients (mean age: 78.2±7.6, 55% female) with complete records of SMI, HGS, and the CFS. The prevalence of low HGS, low SMI, sarcopenia, and frailty were 39.0%, 33.1%, 19.7%, and 39.0%, respectively. Sarcopenia and frailty co-occurred in 12.1% of the patients. CONCLUSIONS: It is well-known that sarcopenia and frailty represent clinical manifestations of ageing and overlap in terms of the impairment in physical function observed in both conditions. Our results demonstrate that sarcopenia and frailty do not necessarily co-occur within the older acutely admitted patient, highlighting the need for separate assessments of frailty and sarcopenia to ensure the accurate characterization of the health status of older patients.


Assuntos
Fragilidade , Sarcopenia , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Masculino , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Estudos Transversais , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Força da Mão , Hospitalização
2.
Radiography (Lond) ; 30(2): 651-658, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38341986

RESUMO

INTRODUCTION: Social media (SoMe) is widely used as a communication platform in everyday life. Also, healthcare professionals have embraced SoMe as a communication tool for both peers and patients. It is becoming an interactive tool for discussing professionals' issues and a place where learning and education occur. This study explores the specific patterns of SoMe use for radiographers' in the Nordic countries. The aim of this survey was to investigate radiographers use of social platforms in a professional setting. METHODS: A 29-item survey was prepared, and pilot-tested. The survey was produced in Danish a language that all Nordic countries master. In general, most Nordic languages are very similar. The survey was distributed by online platforms such as Facebook, LinkedIn, Twitter/X, and also distributed by newsletters by the Norwegian and Danish national radiographers societies. All data was collected anonymously. An Ethical Research approval was obtained from the University of Southern Denmark. RESULTS: A total of 242 respondents completed the survey (Denmark n = 183, Norway n = 48, Sweden n = 8, and n = 3 from other Scandinavian countries). The respondents included 186 females, 52 males and four were undisclosed. On average, the respondents spent approximately 2 h and 23 min daily on SoMe, with 27 min specifically dedicated to content relevant to radiographers. Facebook was the preferred platform with 93 % (n = 226). A total of 5.4 % (n = 13) respondents had experienced contact from patients and/or next of kin, while 92 % (n = 222) reported no such interactions and 2.9 % (n = 7) were undisclosed. A total of 52.8 % (n = 128) used SoMe in relation to courses, conferences, or online meetings. This shows that time spent on content relevant to radiographers imply that SoMe can be a relevant tool for reaching radiographers. CONCLUSION: The survey demonstrates radiographers' use of SoMe for personal and professional interest, with Facebook as the preferred social media platform. SoMe were mostly used during courses, conferences, or online meetings with half of the respondent reported using SoMe platforms during working hours. These results underscore the untapped potential of SoMe in professional healthcare settings. Additionally, the study offers insight into current practices, facilitating comparisons to identify trends in SoMe usage within the radiographer community. IMPLICATIONS FOR PRACTICE: The findings advocate for the strategic use of SoMe by radiographers', emphasizing professional networking and knowledge sharing. However, clear guidelines are necessary to ensure patient confidentiality and data security in these digital interactions.


Assuntos
Mídias Sociais , Masculino , Feminino , Humanos , Pessoal Técnico de Saúde , Pessoal de Saúde , Noruega , Suécia
3.
Sci Rep ; 14(1): 3222, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332140

RESUMO

This manuscript presents the quantification and correlation of three aspects of Alzheimer's Disease evolution, including structural, biochemical, and cognitive assessments. We aimed to test a novel structural biomarker for neurodegeneration based on a cortical folding model for mammals. Our central hypothesis is that the cortical folding variable, representative of axonal tension in white matter, is an optimal discriminator of pathological aging and correlates with altered loadings in Cerebrospinal Fluid samples and a decline in cognition and memory. We extracted morphological features from T1w 3T MRI acquisitions using FreeSurfer from 77 Healthy Controls (age = 66 ± 8.4, 69% females), 31 Mild Cognitive Impairment (age = 72 ± 4.8, 61% females), and 13 Alzheimer's Disease patients (age = 77 ± 6.1, 62% females) of recruited volunteers in Brazil to test its discriminative power using optimal cut-point analysis. Cortical folding distinguishes the groups with reasonable accuracy (Healthy Control-Alzheimer's Disease, accuracy = 0.82; Healthy Control-Mild Cognitive Impairment, accuracy = 0.56). Moreover, Cerebrospinal Fluid biomarkers (total Tau, A[Formula: see text]1-40, A[Formula: see text]1-42, and Lipoxin) and cognitive scores (Cognitive Index, Rey's Auditory Verbal Learning Test, Trail Making Test, Digit Span Backward) were correlated with the global neurodegeneration in MRI aiming to describe health, disease, and the transition between the two states using morphology.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Doença de Alzheimer/patologia , Disfunção Cognitiva/patologia , Biomarcadores/líquido cefalorraquidiano , Cognição , Envelhecimento , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano
4.
J Clin Periodontol ; 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37691160

RESUMO

AIM: To evaluate if, and to what extent, machine learning models can capture clinically defined Stage III/IV periodontitis from self-report questionnaires and demographic data. MATERIALS AND METHODS: Self-reported measures of periodontitis, demographic data and clinically established Stage III/IV periodontitis status were extracted from two Danish population-based cohorts (The Copenhagen Aging and Midlife Biobank [CAMB] and The Danish Health Examination Survey [DANHES]) and used to develop cross-validated machine learning models for the prediction of clinically established Stage III/IV periodontitis. Models were trained using 10-fold cross-validations repeated three times on the CAMB dataset (n = 1476), and the resulting models were validated in the DANHES dataset (n = 3585). RESULTS: The prevalence of Stage III/IV periodontitis was 23.2% (n = 342) in the CAMB dataset and 9.3% (n = 335) in the DANHES dataset. For the prediction of clinically established Stage III/IV periodontitis in the CAMB cohort, models reached area under the receiver operating characteristics (AUROCs) of 0.67-0.69, sensitivities of 0.58-0.64 and specificities of 0.71-0.80. In the DANHES cohort, models derived from the CAMB cohort achieved AUROCs of 0.64-0.70, sensitivities of 0.44-0.63 and specificities of 0.75-0.84. CONCLUSIONS: Applying cross-validated machine learning algorithms to demographic data and self-reported measures of periodontitis resulted in models with modest capabilities for the prediction of Stage III/IV periodontitis in two Danish cohorts.

5.
J Dairy Sci ; 106(10): 6593-6596, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37210359
6.
J Dairy Sci ; 106(5): 3625-3632, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37028972

RESUMO

It is not clear whether cattle that are genetically superior in regulation of body temperature during heat stress are also better able to sustain milk production during hot conditions. Objectives were to evaluate differences in body temperature regulation during heat stress between Holstein, Brown Swiss, and crossbred cows under semi-tropical conditions and test whether the seasonal depression in milk yield was greater for genetic groups less able to regulate body temperature. For the first objective, conducted during heat stress, vaginal temperature was measured at 15-min intervals for 5 d in 133 pregnant lactating cows. Vaginal temperatures were affected by time and interaction between genetic group and time. Vaginal temperatures were higher for Holsteins for most times of the day. Moreover, the maximum daily vaginal temperature was higher for Holstein (39.8 ± 0.1°C) than for Brown Swiss (39.3 ± 0.2°C) or crossbreds (39.2 ± 0.1°C). For the second objective, 6,179 lactation records from 2,976 cows were analyzed to determine effects of genetic group and season of calving (cool season = Oct to March; warm season = April to Sept) on 305-d milk yield. Milk yield was affected by genetic group and season but not by the interaction of genetic group and season. The difference in average 305-d milk yield between cows calving in cool versus hot weather was 310 kg (4% decrease) for Holstein, 480 kg (7% decrease) for Brown Swiss, and 420 kg (6% decrease) for crossbreds. In conclusion, Brown Swiss and crossbreds regulated body temperature during heat stress better than Holsteins but these breeds were not more resistant to heat stress with respect to milk yield. Thus, genetic differences in thermotolerance are likely to exist that are independent of regulation of body temperature.


Assuntos
Lactação , Leite , Gravidez , Feminino , Bovinos , Animais , Lactação/fisiologia , Estações do Ano , Depressão , Regulação da Temperatura Corporal , Resposta ao Choque Térmico , Temperatura Alta , Temperatura Corporal
7.
Curr Res Transl Med ; 71(2): 103380, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36738659

RESUMO

PURPOSE OF THE STUDY: Calreticulin is an endoplasmic reticulum chaperone protein, which is involved in protein folding and in peptide loading of major histocompatibility complex class I molecules together with its homolog calnexin. Mutated calreticulin is associated with a group of hemopoietic disorders, especially myeloproliferative neoplasms. Currently only the cellular immune response to mutated calreticulin has been described, although preliminary findings have indicated that antibodies to mutated calreticulin are not specific for myeloproliferative disorders. These findings have prompted us to characterize the humoral immune response to mutated calreticulin and its chaperone homologue calnexin. PATIENTS AND METHODS: We analyzed sera from myeloproliferative neoplasm patients, healthy donors and relapsing-remitting multiple sclerosis patients for the occurrence of autoantibodies to wild type and mutated calreticulin forms and to calnexin by enzyme-linked immunosorbent assay. RESULTS: Antibodies to mutated calreticulin and calnexin were present at similar levels in serum samples of myeloproliferative neoplasm and multiple sclerosis patients as well as healthy donors. Moreover, a high correlation between antibodies to mutated calreticulin and calnexin was seen for all patient and control groups. Epitope binding studies indicated that cross-reactive antibodies bound to a three-dimensional epitope encompassing a short linear sequence in the C-terminal of mutated calreticulin and calnexin. CONCLUSION: Collectively, these findings indicate that calreticulin mutations may be common and not necessarily lead to onset of myeloproliferative neoplasm, possibly due to elimination of cells with mutations. This, in turn, may suggest that additional molecular changes may be required for development of myeloproliferative neoplasm.


Assuntos
Calreticulina , Neoplasias , Humanos , Calreticulina/genética , Calnexina/genética , Calnexina/química , Calnexina/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo
8.
Scand J Rheumatol ; 52(5): 539-548, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36503382

RESUMO

OBJECTIVES: To evaluate the prevalence of survey-based criteria for fibromyalgia (FM) among newly referred patients in a rheumatic outpatient clinic, and to compare the use of secondary healthcare services between survey-based FM and non-FM cases. METHOD: Newly referred patients to an outpatient clinic were screened for the fulfilment of the 2011 FM survey criteria during a 6 month period in 2013 in this observational cohort study. Demographic data were obtained at baseline. Patients' medical files were evaluated and comparisons between groups were made regarding the use of hospital healthcare facilities during the 7 year observation period. RESULTS: Out of 300 invited patients, 248 (83%) completed the questionnaire; 90 patients (36%) fulfilled survey-based criteria for FM at enrolment. FM cases were primarily women (80% vs 54% of non-FM cases), and received more medications (median 4 vs 3 drugs) and public economic support (62% vs 20%). At the 7 year follow-up, crude analyses showed that FM cases had a higher number of hospital courses (median 10 vs 8) and had undergone more invasive procedures (78% vs 60%). Neurologists (42% vs 28%), gastroenterologists (30% vs 13%), endocrinologists (40% vs 21%), pain specialists (13% vs 3%), psychiatrists (20% vs 7%), and abdominal surgeons (43% vs 30%) were consulted more often by FM than by non-FM cases. CONCLUSION: Fulfilment of FM survey criteria among newly referred patients to a rheumatic outpatient clinic is frequent. Our study findings show that FM continues to present a challenge for healthcare professionals as well as for patients. RESEARCH HIGHLIGHTS: ● Fulfilment of FM survey criteria among newly referred patients to a rheumatic outpatient clinic is frequent.● The burden on the secondary healthcare system for these patients is significant.● This study suggests the need for increased awareness about the diagnosis of FM among certain medical and surgical specialties.


Assuntos
Fibromialgia , Humanos , Feminino , Fibromialgia/diagnóstico , Fibromialgia/epidemiologia , Fibromialgia/terapia , Seguimentos , Prevalência , Instituições de Assistência Ambulatorial , Hospitais , Inquéritos e Questionários
9.
J Dairy Sci ; 105(11): 9206-9215, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36085108

RESUMO

The SLICK1 mutation in the prolactin receptor (PRLR) results in a short-hair coat and increased ability to regulate body temperature during heat stress. It is unclear whether the mutation affects capacity for sweating. The objective of this observational study was to evaluate whether the SLICK1 mutation in PRLR alters characteristics of skin related to sweat gland abundance or function. Skin biopsies from 31 Holstein heifers, including 14 wild-type (SL-/-) and 17 heterozygous slick (SL+/-), were subjected to histological analysis to determine the percent of the surface area of skin sections that are occupied by sweat glands. We detected no effect of genotype on this variable. Immunohistochemical analysis of the forkhead transcription factor A1 (FOXA1), a protein essential for sweating in mice, from 6 SL-/- and 6 SL+/- heifers indicated twice as much FOXA1 in sweat glandular epithelia of SL+/- heifers as in SL-/- heifers. Results from RNA sequencing of skin biopsies from 5 SL-/- and 7 SL+/- heifers revealed few genes that were differentially expressed and none that have been associated with sweat gland development or function. In conclusion, results do not support the idea that the SLICK1 mutation changes the abundance of sweat glands in skin, but do show that functional properties of sweat glands, as indicated by increased abundance of immunoreactive FOXA1, are modified by inheritance of the mutation in PRLR.


Assuntos
Receptores da Prolactina , Glândulas Sudoríparas , Animais , Bovinos , Feminino , Camundongos , Fatores de Transcrição Forkhead/genética , Expressão Gênica , Mutação
10.
J Dairy Sci ; 105(9): 7820-7828, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35879162

RESUMO

Heat stress has negative consequences for milk production and reproduction of dairy cattle. These adverse effects are likely to increase because of climate change and anticipated increases in milk yield. Some of the variation among cows in ability to resist effects of heat stress is genetic. The current objective of this observational study was to assess the effectiveness of the Australian breeding value for heat tolerance (ABVHT) based on the decline in milk yield with heat stress for predicting cow differences in effects of heat stress on regulation of body temperature, milk production, and reproductive function. Genomic breeding values for heat tolerance were calculated for 12,487 cows from a single California dairy farm. Rectal temperature in the afternoon (1100-2045 h) was measured on a subset of 626 lactating cows with ABVHT ≥102 (heat tolerant) or <102 (heat sensitive). Rectal temperature was 0.12°C lower for heat-tolerant cows than heat-sensitive cows. Vaginal temperatures were measured every 15 min for 5 d in 118 cows with ABVHT ≥108 (extreme heat tolerant) or <97 (extreme heat sensitive). Vaginal temperature was 0.07°C lower for extreme heat-tolerant cows than extreme heat-sensitive cows. Lactation records for 4,703 cows with ABVHT were used to evaluate seasonal variation in first 90-d milk yield, fat percent, and protein percent for each ABVHT quartile. Overall, cows with higher ABVHT had lower milk yield, fat percentage, and protein percentage and higher first service pregnancy rate. There was no summer depression in production or reproduction or interactions between season and ABVHT quartile. We observed that ABVHT can successfully identify heat-tolerant cows that maintain lower body temperatures during heat stress. The lack of a pronounced seasonality in milk production or reproduction precluded evaluation of whether ABVHT is related to the magnitude of effect of heat stress on those traits.


Assuntos
Transtornos de Estresse por Calor , Termotolerância , Animais , Austrália , Bovinos , Feminino , Transtornos de Estresse por Calor/metabolismo , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Temperatura Alta , Lactação , Leite/metabolismo , Gravidez
11.
J Eur Acad Dermatol Venereol ; 36(4): 592-601, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34812525

RESUMO

BACKGROUND: Ocular surface diseases (OSDs), including conjunctivitis and blepharitis, are common in atopic dermatitis (AD) patients, but the magnitude and patient characteristics are unclear. OBJECTIVES: To examine the prevalence of OSDs in adults with AD and identify patient characteristics and risk factors. METHODS: We designed a cross-sectional questionnaire-based survey and sent it via a secure public mail to all adult Danes with a hospital diagnosis of AD (ICD-10 code L20.x) registered in the National Patient Register (n = 16 718) between 2000 and 2019 and 7044 (42%) participated. Primary outcomes were OSDs and severity according to Ocular Surface Disease Index (OSDI). Adjusted odds ratios (aOR) were calculated with 95% confidence intervals (CIs) using logistic regression models. RESULTS: Respondents were mostly females and middle-aged (67.4%, mean [SD] age, 39.0 [15.5] years). Based on Patient-Oriented SCORing Atopic Dermatitis 49% had mild AD, 35% moderate, 10% severe and in 6% AD was inactive; 44.3% reported physician-diagnosed asthma bronchiale and 55.8% rhinitis. The lifetime prevalence of OSDs was 66.6% for conjunctivitis, 63.5% for hordeolum, 11.0% for blepharitis, 9.7% for keratitis, 2.0% for pterygium, 1.5% for symblepharon, 1.1% for keratoconus and 12.7% reported current conjunctivitis. Factors associated with lifetime occurrence of conjunctivitis included mild, moderate, and severe AD (aOR = 1.48 [95% CI, 1.02-2.14], aOR = 1.73 [95% CI, 1.19-2.53], aOR = 2.17 [95% CI, 1.42-3.21]), asthma bronchiale and rhinitis (aOR = 1.76 [95% CI, 1.49-2.07]), childhood-onset of AD (aOR = 1.34 [95% CI, 1.16-1.56]) and systemic AD treatment (aOR = 1.27 [95% CI, 1.08-1.50]). Use of soft and hard contact lenses (aOR = 2.15 [95% CI, 1.65-2.80], aOR = 3.35 [95% CI, 1.62-6.92]) were associated with lifetime occurrence of keratitis. Moderate and severe AD, asthma bronchiale and rhinitis were also associated with a higher OSDI level. CONCLUSIONS: This study identified important patient factors associated with OSDs. Clinicians should be attentive of ocular signs and symptoms in AD patients and ask about these.


Assuntos
Conjuntivite , Dermatite Atópica , Oftalmopatias , Adulto , Criança , Conjuntivite/epidemiologia , Estudos Transversais , Dermatite Atópica/complicações , Dermatite Atópica/diagnóstico , Dermatite Atópica/epidemiologia , Oftalmopatias/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Inquéritos e Questionários
12.
Anim Genet ; 52(6): 887-890, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34642995

RESUMO

The slick-hair phenotype in cattle is due to one of a series of mutations in the prolactin receptor (PRLR) that cause truncation of the C-terminal region of the protein involved in JAK2/STAT5 activation during prolactin signaling. Here we evaluated whether the inheritance of the SLICK1 allele, the first slick mutation discovered, is inherited in a fashion consistent with Hardy-Weinberg equilibrium. It was hypothesized that any deleterious effect of inheriting the allele on embryonic or fetal function would result in reduced frequency of the allele in offspring. A total of 525 Holstein and Senepol cattle produced from matings involving one or both parents with the SLICK1 allele were genotyped. The observed frequency of the SLICK1 allele (0.247) was not significantly different than the expected frequency of 0.269. These results support the idea that inheritance of the SLICK1 allele does not act in the embryo or fetus to modify its competence to complete development to term.


Assuntos
Bovinos/genética , Cabelo/fisiologia , Hereditariedade , Fenótipo , Receptores da Prolactina/genética , Alelos , Animais
13.
J Hosp Infect ; 118: 63-69, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34560166

RESUMO

BACKGROUND: Hospital-care-associated infections (HCAIs) represent the most frequent adverse event during care delivery, affecting hundreds of millions of patients around the world. Implementing and ensuring conformity to standard precautions, particularly best hand hygiene practices, is regarded as one of the most important and cheapest strategies for preventing HCAIs. However, despite consistent efforts at increasing conformity to standard hand hygiene practices at hospitals, research has repeatedly documented low conformity levels amongst staff, patients and visitors alike. AIM: The behavioural sciences have documented the potential of adjusting seemingly irrelevant contextual features in order to 'nudge' people to conform to desirable behaviours such as hand hygiene compliance (HHC). In this field experiment we investigate the effect on HHC amongst visitors upon entry of a hospital by varying such features. METHODS: Over 50 days, we observed the HHC of a total of 46,435 hospital visitors upon their entry to the hospital in a field experimental design covering eight variations over the salience, placement and assertion of the hand sanitizer in the foyer, including the presence of the yearly national HHC campaign and a follow up during the COVID-19 pandemic. FINDINGS: Our experiment found that varying seemingly irrelevant features increased HHC from a baseline of 0.4%-19.7% (47.6% during COVID-19). The experiment also found that the national HHC-campaign had no direct statistically significant effect on HHC. CONCLUSION: Varying seemingly irrelevant contextual features provides an effective, generic, cheap and easy to scale approach to increasing HHC relative to sanitizing one's hands at hospitals.


Assuntos
COVID-19 , Infecção Hospitalar , Higiene das Mãos , Infecção Hospitalar/prevenção & controle , Fidelidade a Diretrizes , Desinfecção das Mãos , Hospitais , Humanos , Pandemias , SARS-CoV-2
17.
Cell Tissue Res ; 382(3): 679, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33170338

RESUMO

The first error is on page 5. A sentence lists two genes as SCNA1A and SCNA2A but they should be SCN1A and SCN2A.

18.
J Dairy Sci ; 103(12): 11930-11944, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33041033

RESUMO

Once it enters the uterus at d 4 to 5 after ovulation, the preimplantation bovine embryo is controlled in its development by regulatory signaling molecules from the mother called embryokines. Here, several cell-signaling molecules whose genes are expressed in the endometrium during d 5 to 7 after estrus were tested for the ability to affect the competence of the embryo for further development and the characteristics of the resultant blastocysts. Molecules tested were C-natriuretic peptide (CNP), IL-8, bovine morphogenetic protein 4 (BMP-4), IL-6, and leukemia inhibitory factor (LIF). None of the cell-signaling molecules tested improved the competence of the embryo to become a blastocyst; in fact, BMP-4 decreased development. All molecules modified attributes of the blastocyst formed in culture. In particular, CNP increased the number of cells in the ICM, whereas IL-8 decreased inner cell mass cell numbers and tended to increase the proportion of blastocysts that were hatching or hatched. In addition, BMP-4 decreased the proportion of blastocysts that were hatching. Interleukin-6 and, to a lesser extent, LIF activated the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in the inner cell mass, and LIF increased the percent of cells in the blastocyst that were positive for both NANOG and phosphorylated (activated) STAT3. In conclusion, our results indicate that CNP, IL-8, IL-6, LIF, and BMP-4 can modify embryonic development of the cow in a manner that affects characteristics of the resultant blastocyst. Further research is required to understand how these changes in characteristics of the blastocyst would affect competence of the embryo to establish and maintain pregnancy.


Assuntos
Blastocisto/fisiologia , Bovinos/embriologia , Desenvolvimento Embrionário , Reprodução , Transdução de Sinais , 2',3'-Nucleotídeo Cíclico 3'-Fosfodiesterase , Animais , Transferência Embrionária/veterinária , Feminino , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Fator Inibidor de Leucemia/metabolismo , Fosforilação , Gravidez , Fator de Transcrição STAT3/metabolismo
19.
J Dairy Sci ; 103(11): 10784-10796, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32896407

RESUMO

Choline is a precursor of acetylcholine, phosphatidylcholine, and the methyl-donor betaine. Reports indicate that supplementation with rumen-protected choline improves postpartum reproductive function of dairy cows. The objective was to determine whether addition of choline to culture medium of in vitro-produced embryos alters the phenotype of the resultant blastocysts. Treatments were choline chloride (ChCl; 0.004, 1.3, 1.8, and 6.37 mM) and phosphatidylcholine (1.3 mM). Treatment with 0.004 mM ChCl improved development to the blastocyst stage, increased blastocyst cell number, and increased the percentage of blastocysts that were hatching or hatched. Development was not affected by higher concentrations of ChCl but was reduced by 1.3 mM phosphatidylcholine. Treatment of embryos with 1.3 mM ChCl (but not other concentrations) increased expression in blastocysts of 11 of 165 genes examined (AMOT, NANOG, HDAC8, HNF4A, STAT1, MBNL3, SOX2, STAT3, KDM2B, SAV1, and GPAM) and decreased expression of one gene (ASS1). Treatment with 1.3 mM ChCl decreased global DNA methylation at d 3.5 of development and increased DNA methylation at d 7.5 in blastocysts. Treatment with 1.8 mM ChCl also increased methylation in blastocysts. In conclusion, addition of choline to the culture medium alters the phenotype of preimplantation bovine embryos produced in vitro. Choline chloride can act in a concentration-dependent manner to alter development, expression of specific genes, and DNA methylation.


Assuntos
Blastocisto/efeitos dos fármacos , Colina/farmacologia , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/efeitos dos fármacos , Animais , Bovinos , Meios de Cultura/metabolismo , Metilação de DNA , Fertilização In Vitro/veterinária , Fenótipo
20.
Sci Adv ; 6(37)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32917704

RESUMO

Growing evidence suggests that sexual reproduction might be common in unicellular organisms, but observations are sparse. Limited knowledge of sexual reproduction constrains understanding of protist ecology. Although Teleaulax amphioxeia and Plagioselmis prolonga are common marine cryptophytes worldwide, and are also important plastid donors for some kleptoplastic ciliates and dinoflagellates, the ecology and development of these protists are poorly known. We demonstrate that P. prolonga is the haploid form of the diploid T. amphioxeia and describe the seasonal dynamics of these two life stages. The diploid T. amphioxeia dominates during periods of high dissolved inorganic nitrogen (DIN) and low irradiance, temperature, and grazing (winter and early spring), whereas the haploid P. prolonga becomes more abundant during the summer, when DIN is low and irradiance, temperature, and grazing are high. Dimorphic sexual life cycles might explain the success of this species by fostering high genetic diversity and enabling endurance in adverse conditions.

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