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1.
Antibiotics (Basel) ; 13(6)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38927203

RESUMO

Management of suspected early-onset sepsis (EOS) is undergoing continuous evolution aiming to limit antibiotic overtreatment, yet current data on the level of overtreatment are only available for a select number of countries. This study aimed to determine antibiotic initiation and continuation rates for suspected EOS, along with the incidence of culture-proven EOS in The Netherlands. In this retrospective study from 2019 to 2021, data were collected from 15 Dutch hospitals, comprising 13 regional hospitals equipped with Level I-II facilities and 2 academic hospitals equipped with Level IV facilities. Data included birth rates, number of neonates started on antibiotics for suspected EOS, number of neonates that continued treatment beyond 48 h and number of neonates with culture-proven EOS. Additionally, blood culture results were documented. Data were analysed both collectively and separately for regional and academic hospitals. A total of 103,492 live-born neonates were included. In 4755 neonates (4.6%, 95% CI 4.5-4.7), antibiotic therapy was started for suspected EOS, and in 2399 neonates (2.3%, 95% CI 2.2-2.4), antibiotic treatment was continued beyond 48 h. Incidence of culture-proven EOS was 1.1 cases per 1000 live births (0.11%, 95% CI 0.09-0.14). Overall, for each culture-proven EOS case, 40.6 neonates were started on antibiotics and in 21.7 neonates therapy was continued. Large variations in treatment rates were observed across all hospitals, with the number of neonates initiated and continued on antibiotics per culture-proven EOS case varying from 4 to 90 and from 4 to 56, respectively. The high number of antibiotic prescriptions compared to the EOS incidence and wide variety in clinical practice among hospitals in The Netherlands underscore both the need and potential for a novel approach to the management of neonates with suspected EOS.

2.
Epileptic Disord ; 26(1): 1-59, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38116690

RESUMO

Epilepsy surgery is the therapy of choice for many patients with drug-resistant focal epilepsy. Recognizing and describing ictal and interictal patterns with intracranial electroencephalography (EEG) recordings is important in order to most efficiently leverage advantages of this technique to accurately delineate the seizure-onset zone before undergoing surgery. In this seminar in epileptology, we address learning objective "1.4.11 Recognize and describe ictal and interictal patterns with intracranial recordings" of the International League against Epilepsy curriculum for epileptologists. We will review principal considerations of the implantation planning, summarize the literature for the most relevant ictal and interictal EEG patterns within and beyond the Berger frequency spectrum, review invasive stimulation for seizure and functional mapping, discuss caveats in the interpretation of intracranial EEG findings, provide an overview on special considerations in children and in subdural grids/strips, and review available quantitative/signal analysis approaches. To be as practically oriented as possible, we will provide a mini atlas of the most frequent EEG patterns, highlight pearls for its not infrequently challenging interpretation, and conclude with two illustrative case examples. This article shall serve as a useful learning resource for trainees in clinical neurophysiology/epileptology by providing a basic understanding on the concepts of invasive intracranial EEG.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Epilepsia , Criança , Humanos , Eletrocorticografia/métodos , Epilepsias Parciais/diagnóstico , Epilepsias Parciais/cirurgia , Eletroencefalografia/métodos , Convulsões/diagnóstico , Epilepsia Resistente a Medicamentos/diagnóstico , Epilepsia Resistente a Medicamentos/cirurgia
4.
Immunohematology ; 39(1): 32-34, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37017601

RESUMO

Dia is one of the most clinically significant low-prevalence antigens in the Diego blood group system, since antibodies to Dia have, albeit rarely, been implicated in hemolytic transfusion reactions and hemolytic disease of the fetus and newborn (HDFN). Given the geographical association, most anti-Dia HDFN cases have been reported in Japan, China, and Poland. We describe a case of HDFN in a neonate born to a 36-year-old G4P2012 woman of self-identified Hispanic ethnicity and of South American descent with multiple negative antibody detection tests in a U.S. hospital. Upon delivery, a cord blood direct antiglobulin test was positive (3+ reactivity), and neonatal bilirubin levels were moderately elevated, but phototherapy and transfusion were not required. This case highlights a rare, unexpected cause of HDFN in the United States secondary to anti-Dia, given the near-universal absence of this antigen and antibody in most U.S. patient populations. The case also demonstrates the need for awareness of antibodies to antigens that are considered "low-prevalence" in most populations but that might be encountered more frequently in specific racial or ethnic groups and may require more extensive testing.


Assuntos
Eritroblastose Fetal , Feminino , Recém-Nascido , Humanos , Adulto , Eritroblastose Fetal/diagnóstico , Transfusão de Sangue , Teste de Coombs , Hemólise , Feto , Hospitais
5.
Epilepsy Behav ; 143: 109221, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37119580

RESUMO

Since the discovery of the human electroencephalogram (EEG), neurophysiology techniques have become indispensable tools in our armamentarium to localize epileptic seizures. New signal analysis techniques and the prospects of artificial intelligence and big data will offer unprecedented opportunities to further advance the field in the near future, ultimately resulting in improved quality of life for many patients with drug-resistant epilepsy. This article summarizes selected presentations from Day 1 of the two-day symposium "Neurophysiology, Neuropsychology, Epilepsy, 2022: Hills We Have Climbed and the Hills Ahead". Day 1 was dedicated to highlighting and honoring the work of Dr. Jean Gotman, a pioneer in EEG, intracranial EEG, simultaneous EEG/ functional magnetic resonance imaging, and signal analysis of epilepsy. The program focused on two main research directions of Dr. Gotman, and was dedicated to "High-frequency oscillations, a new biomarker of epilepsy" and "Probing the epileptic focus from inside and outside". All talks were presented by colleagues and former trainees of Dr. Gotman. The extended summaries provide an overview of historical and current work in the neurophysiology of epilepsy with emphasis on novel EEG biomarkers of epilepsy and source imaging and concluded with an outlook on the future of epilepsy research, and what is needed to bring the field to the next level.


Assuntos
Inteligência Artificial , Epilepsia , Humanos , Neuropsicologia , Qualidade de Vida , Mapeamento Encefálico/métodos , Eletroencefalografia/métodos
6.
S Afr J Sports Med ; 35(1): v35i1a15144, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38249757

RESUMO

Background: Despite differences between left- and right-handed athletes in other sports, minimal evidence exists regarding biomechanical similarities and differences between left- and right-handed cricket fast bowlers performing an equivalent task. Objectives: This study aimed to compare the kinematics between left and right-handed fast bowlers performing an equivalent task (i.e. bowling 'over the wicket' to a batter of the same handedness as the bowler). Methods: Full body, three-dimensional kinematic data for six left-handed and 20 right-handed adolescent, male, fast bowlers were collected using the Xsens inertial measurement system. Time-normalised joint and segment angle time histories from back foot contact to follow-through ground contacts were compared between groups via statistical parametric mapping. Whole movement and subphase durations were also compared. Results: Left-handed players displayed significantly more trunk flexion from 49%-56% of the total movement (ball release occurred at 54%; p = 0.037) and had shorter back foot contact durations on average (0.153 vs 0.177 s; p = 0.036) compared to right-handed players. Conclusion: Left- and right-handed bowlers displayed similar sagittal plane kinematics but appeared to use non-sagittal plane movements differently around the time of ball release. The kinematic differences identified in this study can inform future research investigating the effect of hand dominance on bowling performance and injury risk.

7.
Science ; 378(6621): eabg3679, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36395225

RESUMO

The Hippo signaling pathway is widely considered a master regulator of organ growth because of the prominent overgrowth phenotypes caused by experimental manipulation of its activity. Contrary to this model, we show here that removing Hippo transcriptional output did not impair the ability of the mouse liver and Drosophila eyes to grow to their normal size. Moreover, the transcriptional activity of the Hippo pathway effectors Yap/Taz/Yki did not correlate with cell proliferation, and hyperactivation of these effectors induced gene expression programs that did not recapitulate normal development. Concordantly, a functional screen in Drosophila identified several Hippo pathway target genes that were required for ectopic overgrowth but not normal growth. Thus, Hippo signaling does not instruct normal growth, and the Hippo-induced overgrowth phenotypes are caused by the activation of abnormal genetic programs.


Assuntos
Drosophila melanogaster , Olho , Regulação da Expressão Gênica no Desenvolvimento , Via de Sinalização Hippo , Fígado , Transcrição Gênica , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAP , Animais , Camundongos , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Olho/embriologia , Via de Sinalização Hippo/genética , Fígado/embriologia , Tamanho do Órgão , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transativadores/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional/metabolismo , Proteínas de Sinalização YAP/metabolismo
8.
Am Ann Deaf ; 167(1): 50-53, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35848320
9.
Am Ann Deaf ; 167(1): 56-58, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35848322
10.
Microbiol Resour Announc ; 10(50): e0089321, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34913716

RESUMO

Erwinia amylovora is the causative agent of fire blight, a devastating disease of apples and pears worldwide. Here, we report draft genome sequences of four streptomycin-sensitive strains of E. amylovora that were isolated from diseased apple trees in Ohio.

11.
Phys Med Biol ; 66(14)2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34157703

RESUMO

Patient dose management systems can be part of a department's quality management tools to estimate items such as the radiation burden in specific groups or list dose outliers for further follow up. Patient size information could improve both aspects, but is not generally available. A new metric is proposed to estimate patient size for thorax and abdominal projection radiography from parameters available in thedicomheader and therefore accessible by dose management software. The tested hypothesis was that an attenuation metric, related to the ratio of detector air-kerma to incident air-kerma, inversely correlates with patient size. Such a metric was defined and then worked out for thorax and abdomen projection radiography. Input material consisted of the thorax or abdominal radiographs of 137 cases, completed with a recent CT scan as ground truth size. From the CT, the water equivalent diameter (WED) and water equivalent thickness (WET) were calculated. The correlation between the attenuation metric and the patient size was established separately for thorax and abdomen. Validation of the attenuation metric predicting the patient size was performed using extra sets of examinations on three more radiographic x-ray devices, with available CT scan. The attenuation metric had a good correlation (R2) of 0.91 and 0.84 with the WED for thorax and abdomen respectively. The corresponding values for the WET were 0.89 and 0.78. Validation of the methodology on the devices with standardized exposure index in thedicomheaders showed that the WED could be estimated within ±15% and the WET within ±30% for thorax and abdomen examinations. The ground truth and estimated size were found statistically equivalent. An attenuation metric based ondicomtags allows to estimate the patient size in projection radiography. This could now be implemented in patient dose management systems.


Assuntos
Radiografia Abdominal , Tomografia Computadorizada por Raios X , Abdome/diagnóstico por imagem , Adulto , Humanos , Imagens de Fantasmas , Doses de Radiação , Radiografia Torácica , Raios X
13.
Mol Cell Probes ; 56: 101695, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33453365

RESUMO

Researchers have developed multiple methods to characterize clinical and environmental strains of Vibrio vulnificus. The aim of our study was to use four assays to detect virulence factors in strains from infected patients and those from surface waters/sediments/oysters of South Carolina and the Gulf of Mexico. Vibrio vulnificus strains from clinical (n = 81) and environmental (n = 171) sources were tested using three real-time PCR methods designed to detect polymorphisms in the 16S rRNA, vcg and pilF genes and a phenotypic method, the ability to ferment D-mannitol. Although none of the tests correctly categorized all isolates, the differentiation between clinical and environmental isolates was similar for the pilF, vcgC/E and 16S rRNA assays, with sensitivities of 74.1-79.2% and specificities of 77.4-82.7%. The pilF and vcgC/E assays are comparable in efficacy to the widely used 16S rRNA method, while the D-mannitol fermentation test is less discriminatory (sensitivity = 77.8%, specificity = 61.4%). Overall percent agreement for the D-mannitol fermentation method was also lower (66.7%) than overall percent agreement for the 3 molecular assays (78.0%-80.2%). This study demonstrated, using a large, diverse group of Vibrio vulnificus isolates, that three assays could be used to distinguish most clinical vs environmental isolates; however, additional assays are needed to increase accuracy.


Assuntos
Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Vibrioses/diagnóstico , Vibrio vulnificus/genética , Vibrio vulnificus/patogenicidade , Animais , Proteínas de Bactérias/metabolismo , Fermentação , Expressão Gênica , Humanos , Manitol/metabolismo , RNA Ribossômico 16S/genética , Alimentos Marinhos/microbiologia , Frutos do Mar/microbiologia , Estados Unidos , Vibrioses/microbiologia , Vibrioses/patologia , Vibrio vulnificus/isolamento & purificação , Virulência , Microbiologia da Água
14.
Neth Heart J ; 29(5): 255-261, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33410120

RESUMO

BACKGROUND: The current standard of care for acute atrial fibrillation (AF) focuses primarily on immediate restoration of sinus rhythm by cardioversion, although AF often terminates spontaneously. OBJECTIVE: To identify determinants of early spontaneous conversion (SCV) in patients presenting at the emergency department (ED) because of AF. METHODS: An observational study was performed of patients who visited the ED with documented AF between July 2014 and December 2016. The clinical characteristics and demographics of patients with and without SCV were compared. RESULTS: We enrolled 943 patients (age 69 ± 12 years, 47% female). SCV occurred within 3 h of presentation in 158 patients (16.8%). Logistic regression analysis showed that duration of AF <24 h [odds ratio (OR) 7.7, 95% confidence interval (CI) 3.5-17.2, p < 0.001], left atrial volume index <42 ml/m2 (OR 1.8, 95% CI 1.2-2.8, p = 0.010), symptoms of near-collapse at presentation (OR 2.4, 95% CI 1.2-5.1, p = 0.018), a lower body mass index (BMI) (OR 0.9, 95% CI 0.91-0.99, p = 0.028), a longer QTc time during AF (OR 1.01, 95% CI 1.0-1.02, p = 0.002) and first-detected AF (OR 2.5, 95% CI 1.6-3.9, p < 0.001) were independent determinants of early SCV. CONCLUSION: Early spontaneous conversion of acute AF occurs in almost one-sixth of admitted patients during a short initial observation in the ED. Spontaneous conversion is most likely to occur in patients with first-onset, short-duration AF episodes, lower BMI, and normal left atrial size.

15.
Clin Microbiol Infect ; 27(4): 590-596, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32505586

RESUMO

OBJECTIVES: Areas with declining malaria transmission in sub-Saharan Africa have recently witnessed important changes in the aetiology of childhood acute febrile illness (AFI). We describe the aetiology of AFI in a high malaria transmission area in rural Burkina Faso. METHODS: In a prospective hospital-based diagnostic study, children aged 3 months to 15 years with AFI were recruited and assessed using a systematic diagnostic protocol, including blood cultures, whole blood PCR on a selection of bacterial pathogens, malaria diagnostics and a multiplex PCR on nasopharyngeal swabs targeting 21 viral and 4 bacterial respiratory pathogens. RESULTS: A total of 589 children with AFI were enrolled from whom an infectious disease was considered in 575 cases. Acute respiratory tract infections, malaria and invasive bacterial infections (IBI) accounted for 179 (31.1%), 175 (30.4%) and 75 (13%) of AFI cases respectively; 16 (21.3%) of IBI cases also had malarial parasitaemia. A viral pathogen was demonstrated from the nasopharynx in 157 children (90.7%) with respiratory tract symptoms. Of all children with viral respiratory tract infections, 154 (92.4% received antibiotics, whereas no antibiotic was provided in 13 (17%) of IBI cases. CONCLUSIONS: Viral respiratory infections are a common cause of childhood AFI in high malaria transmission areas, next to malaria and IBI. These findings highlight the importance of interventions to improve targeted treatment with antimicrobials. Most patients with viral infections received antibiotics unnecessarily, while a considerable number with IBI did not receive antibiotics.


Assuntos
Infecções Bacterianas/diagnóstico , Infecções Bacterianas/epidemiologia , Malária/epidemiologia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Adolescente , Burkina Faso/epidemiologia , Criança , Pré-Escolar , Feminino , Febre , Humanos , Lactente , Malária/transmissão , Masculino , Infecções Respiratórias/epidemiologia , População Rural
16.
Acta Oncol ; 60(2): 222-228, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33269958

RESUMO

PURPOSE: To investigate the dosimetric impact of breathing motion on robustly optimized proton therapy treatment plans for left-sided breast cancer patients with an indication for locoregional irradiation. MATERIALS AND METHODS: Clinical Target Volumes (CTVs) (left-sided breast, level 1 to 4 axillary lymph nodes, interpectoral and internal mammary lymph node regions) and organs at risk were delineated on 4 D-CTs of ten female patients. After treatment planning to a prescribed dose of 40.05 Gy(RBE) in 15 fractions on the time-averaged CT, the dose was calculated on all ten phases of the breathing cycle. Robustness to setup (5 mm) and range errors (3%) was evaluated for those ten phases. Correlations were evaluated between the phases of the breathing cycle and the D98% of the CTV and the Dmean of the heart. RESULTS: Correlations coefficients were between -0.12 and 0.29. At the most extreme values of the 28 robustness scenarios, the clinical goals were met for all but two patients. The mean heart dose was 0.41 Gy(RBE) with a standard deviation of 0.31 Gy(RBE) of proton therapy plans. CONCLUSION: The effect of breathing motion on the robustness of proton therapy treatment plans for this patient group is minor and not of clinical significance. Based on this patient group, a deep-inspiration breath hold seems to be unnecessary to improve robustness for these patients.


Assuntos
Neoplasias da Mama , Terapia com Prótons , Neoplasias Unilaterais da Mama , Neoplasias da Mama/radioterapia , Suspensão da Respiração , Feminino , Coração , Humanos , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Respiração , Neoplasias Unilaterais da Mama/radioterapia
18.
Arthritis Res Ther ; 22(1): 205, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907614

RESUMO

OBJECTIVES: The CAMERA-II trial compared two tight-control, treat-to-target strategies, initiating methotrexate with prednisone (MTX+pred) or MTX with placebo (MTX+plac), in early RA-patients. The multi-biomarker disease activity (MBDA) blood test objectively measures RA disease activity with a score of 1-100. In CAMERA-II, response profiles of the MBDA score, its individual biomarkers, and DAS28 were assessed. METHODS: We evaluated 92 patients from CAMERA-II of whom clinical data and serum for MBDA testing at baseline and ≥ 1 time-point from months 1, 2, 3, 4, 5, 6, 9, or 12 were available. Changes (∆) from baseline for DAS28 and MBDA score and comparisons of ∆DAS28 and ∆MBDA score over time within the MTX+pred versus the MTX+plac strategy were tested for significance with t tests. Changes in biomarker concentration from baseline to months 1-5 were tested with Wilcoxon signed rank test and tested for difference between treatment arms by Mann-Whitney U test. RESULTS: MBDA and DAS28 showed similar response profiles, with gradual improvement over the first 6 months in the MTX+plac group, and in the MTX+pred group faster improvement during month 1, followed by gradual improvement. The 12 MBDA biomarkers could be grouped into 4 categories of response profiles, with significant responses for 4 biomarkers during the MTX+plac strategy and 9 biomarkers during the MTX+pred strategy. CONCLUSIONS: MBDA tracked treatment response in CAMERA-II similarly to DAS28. More individual MBDA biomarkers tracked treatment response to MTX+pred than to MTX+plac. Four response profiles could be observed. TRIAL REGISTRATION: CAMERA-II International Standard Randomised Controlled Trial Number: ISRCTN 70365169 . Registered on 29 March 2006, retrospectively registered.


Assuntos
Antirreumáticos , Artrite Reumatoide , Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Biomarcadores , Progressão da Doença , Quimioterapia Combinada , Humanos , Metotrexato/uso terapêutico , Prednisona/uso terapêutico , Índice de Gravidade de Doença , Resultado do Tratamento
19.
Med Hypotheses ; 143: 109884, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32512289

RESUMO

SARS-CoV-2 is a novel beta-coronavirus causing over 200.000 lethal cases within six months of first infecting humans. SARS-CoV-2 causes COVID-19, a form of severe acute respiratory syndrome (SARS). COVID-19 is characterized by two phases: the first resembles the flu with pneumonia, but after about seven or eight days the disease suddenly worsens to a sepsis-like syndrome. It is difficult to explain this virus-immune-pathology sequence from virology or immunology only. This paper hypothesizes that host-produced anti-spike protein antibodies are responsible for immune-induced viral dissemination. Subsequently, systemic distribution of virus-antibodies complexes activates the immune pathology observed in severe COVID-19. This hypothesis may be counterintuitive to immunologist that consider many anti-spike antibodies to be virus-neutralizing antibodies. Although anti-spike antibodies may hinder infection of epithelial cells, antibody binding to the spike protein may facilitate virus infection of myeloid leukocytes. If myeloid leukocytes reenter the circulation, they could spread the virus from a locoregional infection to a systemic disease. Disseminated virus in combination with antibodies results in dispersed virus-antibody complexes that overstimulate the immune system. The hypothesis aligns with the sequences of virus, immune and pathological events in COVID-19. The delay in onset from both syndromes results from an immune system still naïve to the non-cross-reactive spike protein. Details of this hypothesis are in concordance with many clinical characteristics of COVID-19, including its predominant lethality for the elderly, and the mostly asymptomatic course of disease in children. It predicts putative detrimental effects of vaccines that induce virus-neutralizing antibodies against the spike protein, as has been shown for other coronaviruses. This hypothesis has consequences for treatment of patients, evaluation of personal and herd immunity and vaccine development. In patients, cellular immunity should be stimulated. Neutralizing antibodies might not be indicative for immunity. Vaccines should aim to stimulate cellular immunity COVID-19 and/or stimulate humoral immunity against viral proteins except for the immunodominant spike protein.


Assuntos
Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Betacoronavirus , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Modelos Imunológicos , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Betacoronavirus/imunologia , COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/genética , Infecções por Coronavirus/prevenção & controle , Reações Cruzadas , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Imunidade Celular , Pandemias , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/genética , Vacinas Virais/imunologia
20.
Poult Sci ; 99(1): 142-150, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32416795

RESUMO

This study examined effect of a dietary synbiotic supplement on the concentrations of plasma thyroid hormones, expressions of heat shock protein 70 (HSP70), and intestinal histomorphology in broiler chickens exposed to cyclic heat stress (HS). Three hundred and sixty day old male Ross 708 broiler chicks were randomly distributed among 3 dietary treatments containing a synbiotic (PoultryStar meUS) at 0 (control), 0.5 (0.5×), and 1.0 (1.0×) g/kg. Each treatment contained 8 replicates of 15 birds each housed in floor pens in a temperature and lighting controlled room. Heat stimulation was established from days 15 to 42 at 32°C for 9 h daily. The results indicated that under the HS condition, both synbiotic fed groups had lower liver and hypothalamus HSP70 levels (P < 0.001) compared to control group; however, HSP70 mRNA expression was not different among treatments (P > 0.05). There were no treatment effects on the levels of triiodothyronine (T3) and thyroxine (T4) as well as T3/T4 ratio (P > 0.05). Compared to controls, 1.0× HS broilers had greater villus height in the duodenum (P < 0.01), and greater villus height and villus height:crypt depth ratios in the ileum (P < 0.01). There were no differences among treatments on the measured intestinal parameters in the jejunum (P > 0.05). The results suggest that the synbiotic may ameliorate the negative effects of HS on chicken health as indicated by the changes in the intestinal architecture and the levels of HSP70. Dietary synbiotic supplement could be a feasible nutritive strategy for the poultry industry to improve the health and welfare of chickens when exposed to hot environmental temperature.


Assuntos
Galinhas/fisiologia , Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Temperatura Alta , Intestinos/anatomia & histologia , Simbióticos/administração & dosagem , Hormônios Tireóideos/metabolismo , Criação de Animais Domésticos/métodos , Animais , Galinhas/genética , Galinhas/crescimento & desenvolvimento , Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/metabolismo , Intestinos/efeitos dos fármacos , Intestinos/crescimento & desenvolvimento , Masculino , Distribuição Aleatória
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