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1.
Radiat Prot Dosimetry ; 199(15-16): 1958-1962, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819298

RESUMO

We present comprehensive Monte Carlo simulations for the neutron response of the multi-element microdosimetric detector based on THick Gas Electron Multiplier (THGEM). Simulations were carried out using the MCNP6.2 code to calculate the deposited energy spectrum in the gaseous sensitive volumes for three different configurations, 7 × 3, 19 × 5, 37 × 7 that occupy a cylindrical volume of 5-cm diameter by 5-cm length. The energy response was computed from 10 keV to 2 MeV. The response variation was investigated between sensitive volumes as well as between layers. The simulated energy response showed a good agreement against the evaluated fluence-to-kerma conversion coefficients in the energy region 10-100 keV, whereas discrepancies were observed in the region above 250 keV. The angular response simulations showed a variation of less than 10%.


Assuntos
Elétrons , Radiometria , Método de Monte Carlo , Nêutrons , Simulação por Computador , Gases
2.
Appl Radiat Isot ; 177: 109902, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34481317

RESUMO

In this article, we present a methodology for performing eye lens dosimetry in CANDU nuclear power plants using an existing and highly accurate Harshaw 4-element TLD-700 dosemeter. This dosemeter, which has been specially designed for Ontario Power Generation (OPG) and Bruce Power (BP), measures the deep and shallow personal dose equivalent quantities Hp(10) and Hp(0.07), respectively. Using these measured personal dose equivalent quantities and applying a beta-ray strength scaling factor to the Hp(0.07) measurement in particular, we have developed an algorithm that can be used to calculate the dose to the lens of the eye in mixed beta-gamma fields. This scaling factor has been developed and is primarily based on results obtained from extensive collaborative study, performed by Ontario Power Generation (OPG), Bruce Power (BP) and McMaster University, through Candu Owners Group (COG) support (Bohra et al., 2021; Laranjeiro et al., 2020). Furthermore, scaling factor F, also includes effects of protective glass eyewear and results from Whole body dosimetry intercomparison exercises. The algorithm to calculate eye lens dose at CANDU power plants has been developed, based on this scaling factor and operational dosimetric quantities Hp(10) and Hp(0.07).


Assuntos
Cristalino/efeitos da radiação , Centrais Nucleares , Exposição Ocupacional/análise , Radiometria/métodos , Algoritmos , Canadá , Humanos
3.
Physiol Res ; 70(3): 401-412, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-33982581

RESUMO

High dependency of arterial blood pressure (ABP) on enhanced sympathetic activity, which maintains vascular tone, leads to hypotension after hemodynamic insults that blunt the sympathetic activity. Therefore, we hypothesized that sympathovagal balance before tourniquet deflation (TD) determines the extent of a reduction in ABP after TD during total knee arthroplasty (TKA). Fifty-four hypertensive female patients undergoing TKA under spinal anesthesia were analyzed. The sympathovagal balance [low-to-high frequency ratio of heart rate variability (LF/HF)] before TD was defined as (LF/HF during 5 min before TD-preanesthetic LF/HF)/preanesthetic LF/HF (%). An increase in its value represents a shift in sympathovagal balance toward sympathetic predominance. The percent change in the mean ABP (MAP) after TD was defined as (minimum MAP during 10 min after TD-averaged MAP during 5 min before TD)/averaged MAP during 5 min before TD (%). Simple linear regression was performed to assess the correlation between the sympathovagal balance before TD and change in MAP after TD. The correlation was also assessed by multiple linear regression controlling for age, duration of tourniquet inflation, and spinal anesthesia-induced hypotension. Thirty-two minutes (on average) after tourniquet inflation, the MAP was decreased by 12.1 (-3.0 to 47.9) % [mean (range)] upon TD (P<0.001). The sympathovagal balance before TD was negatively proportional to the change in MAP after TD in both simple and multiple linear regression models (R2=0.323 and 0.340, P<0.001). A shift in sympathovagal balance toward sympathetic predominance before TD is associated with a decrease in ABP after TD.


Assuntos
Pressão Arterial , Artroplastia do Joelho , Sistema Nervoso Simpático/fisiopatologia , Torniquetes , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Raquianestesia , Feminino , Frequência Cardíaca , Humanos , Hipertensão/fisiopatologia , Período Intraoperatório , Pessoa de Meia-Idade , Resultado do Tratamento , Nervo Vago/fisiopatologia
4.
Appl Radiat Isot ; 174: 109746, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33930726

RESUMO

To address the issue of eye lens dosimetry in nuclear industry, we initiated the project to quantify the beta and gamma-ray source term in CANDU power plants and to convert this source term into dosimetric quantities of interest, such as eye lens dose and personal dose equivalents Hp(10), Hp(0.07). This way, the eye lens dose can be compared with dosimetric operational quantities to evaluate whether independent dosimetry is required for eye lens protection, or present dosimetry is adequate.


Assuntos
Partículas beta , Raios gama , Cristalino/efeitos da radiação , Centrais Elétricas , Radiometria/métodos , Humanos , Método de Monte Carlo , Radiometria/instrumentação , Contagem de Cintilação/métodos , Pele/efeitos da radiação
5.
Rhinology ; 59(3): 292-300, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33315021

RESUMO

BACKGROUND: Chronic rhinosinusitis (CRS) and chronic otitis media (COM) share pathophysiological mechanisms such as bacterial infection, biofilm, and persistence of the obstruction state of ventilation routes. However, only a few studies have investigated the relationship between these two diseases nationwide and in the general population. The purpose of this study was to determine whether the incidence of COM in patients with CRS differed from that of a matched control from the national health screening cohort. METHODS: Data from the Korean Health Insurance Review and Assessment Service-National Patient Samples were collected from 2002 to 2015. Participants who were treated ≥ ≥ ≥2 times and underwent head and neck computed tomography evaluation were selected. A 1:4 matched CRS group (n=8,057) and a control group (n=32,228) were selected. The control group included participants who were never treated with the ICD-10 code J32 from 2002 to 2015. The CRS group included CRS patients with/without nasal polyps. RESULTS: The incidence of COM was significantly higher in the CRS group than in the control group. In a subgroup analysis, the incidence of COM in all age groups and in men and women was significantly higher in the CRS group than in the control group. More, CRS increased the risk of COM. CONCLUSIONS: A significant association was observed between CRS and COM. This indicates that CRS patients have a high risk of developing COM.


Assuntos
Pólipos Nasais , Otite Média , Rinite , Sinusite , Doença Crônica , Feminino , Seguimentos , Humanos , Masculino , Otite Média/complicações , Otite Média/epidemiologia , Rinite/epidemiologia , Sinusite/epidemiologia
6.
Radiat Prot Dosimetry ; 192(3): 309-320, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33320200

RESUMO

Gamma-ray spectra were measured using a LaBr$_{3}$(Ce) spectrometer during the outage periods, aiming at quantifying the gamma source term of radiation workers' exposure, at the CANDU nuclear power reactors, for the purposes of eye lens dosimetry. The spectra were measured inside the boiler rooms, of the Bruce Power and Ontario Power Generation (OPG) CANDU nuclear power plants, where workers are exposed to relatively high dose rates radiation fields during the maintenance work. Prior to measurements at the CANDU reactors, the pulse shaping parameters of the gamma spectrometer were optimised for high rates gamma fields, up to an input rates of 120 kcps, in order to accomplish a high output rate with a reasonable energy resolution. In parallel, the response of the LaBr$_{3}$(Ce) detector was characterized by experiments and Monte Carlo simulations. The gamma spectra measured at the CANDU reactors were reported in terms of the gamma-ray fluence rate spectrum. In all measured data, $^{60}$Co and $^{95}$Nb were main contributors of the gamma fields. The measured spectra have been used to calculate the dosimetric quantities of interest: personal dose equivalents H$_{p}$(10) and H$_{p}$(0.07) and eye lens absorbed dose.


Assuntos
Cristalino , Centrais Nucleares , Brometos , Humanos , Lantânio , Método de Monte Carlo , Radiometria
7.
Eur J Paediatr Dent ; 21(3): 238-242, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32893659

RESUMO

BACKGROUND: Molar Incisor Malformation (MIM) or Molar Root Incisor malformation (MRIM) is a recently discovered root malformation with constricted pulp and abnormally located furcation presented in permanent first molars and sometimes incisors. CASE REPORT: Two cases that feature MIM are presented with the description of the characteristic tooth form, clinical/radiographic examination, medical history, the supposed aetiology, treatment procedure and results at the 2-year follow-up. Conservative endodontic treatment was performed in both cases, furcation perforation and canal perforation were filled with MTA (Mineral Trioxide Aggregate), and a good prognosis was observed after 2 years of follow-up. Furthermore, recommended treatment options are discussed to provide a more appropriate treatment for the patients. CONCLUSION: Patients with MIM need to be treated at the right time to avoid severe infection and other problems. Early diagnosis with appropriate treatment is more likely to lead to a more favourable prognosis.


Assuntos
Incisivo , Materiais Restauradores do Canal Radicular , Compostos de Alumínio , Compostos de Cálcio , Polpa Dentária , Cavidade Pulpar , Combinação de Medicamentos , Humanos , Dente Molar , Óxidos , Silicatos , Raiz Dentária
8.
Eye (Lond) ; 34(10): 1909-1915, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32080352

RESUMO

PURPOSE: Historically, atopic dermatitis (AD) is associated with an increased risk of rhegmatogenous retinal detachment (RRD). However, uncertainty remained regarding the effect of AD itself and comorbidities (e.g., allergic diseases, cataract surgery) on RRD occurrence in a large, population-based paediatric population. PATIENTS AND METHODS: We analysed the 12-year National Health Insurance Service database (2002-2013) covering the entire Korean population to estimate the association between AD and RRD in people aged under 20 years. RESULTS: We identified 3142 RRD patients, and matched 18,852 controls (six controls to each RRD patient); therefore, we included 21,994 peoples under aged 20 years in the analyses. AD was more prevalent in the RRD group (329 patients, 10.47%) than the control group (1043 patients, 5.53%; P < 0.001), and so were severe AD (153 patients [4.87%] and 223 patients [1.18%], respectively; P < 0.001). In conditional logistic regression analysis, AD was associated with RRD (OR, 1.61; 95% CI, 1.93-1.87) even after adjusting for allergic conditions, connective tissue disease, uveitis, and cataract surgery. In addition, severity of AD was associated with an increased risk of RRD (OR for non-severe AD and severe AD, 1.26 [95% CI, 1.05-1.51] and 2.88 [95% CI, 2.25-3.68]). CONCLUSION: This study suggests that AD itself is a risk factor of RRD in children by showing the association between AD and RRD occurrence and the biologic gradient even after adjustment for known confounders including allergic conditions, uveitis, and cataract surgery.


Assuntos
Dermatite Atópica , Descolamento Retiniano , Criança , Estudos de Coortes , Dermatite Atópica/complicações , Dermatite Atópica/epidemiologia , Humanos , Descolamento Retiniano/epidemiologia , Estudos Retrospectivos , Fatores de Risco
9.
Br Poult Sci ; 61(1): 22-25, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31615265

RESUMO

1. This experiment investigated the influence of chicken PRDX3 on cell proliferation in chick embryo fibroblast cells using PRDX3 knockdown technology.2. A methyl thiazolyl tetrazolium (MTT) assay was performed to assess the effect of chPRDX3 knockdown on fibroblast proliferation. The antioxidant effect was investigated to determine if it directly mediated fibroblast cell proliferation.3. To determine the role of chPRDX3 on cell proliferation, an siRNA mediated knockdown was performed in chick fibroblast cells using an in vitro assay. The proliferation of fibroblast cells transfected with siPRDX3 #3 and siPRDX3 Mix was significantly decreased after 48 h (P < 0.01). In addition, the knockdown of chicken PRDX3 suppressed cell proliferation through an increase in oxidative stress.4. The results demonstrated that chPRDX3 is required for cell proliferation in chicken fibroblast cells. Such findings have important implications for the maintenance of chicken fibroblast cells.


Assuntos
Galinhas , Peroxirredoxina III , Animais , Proliferação de Células , Embrião de Galinha , Fibroblastos , RNA Interferente Pequeno
10.
Health Phys ; 117(3): 300-305, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31349356

RESUMO

In a search to optimize neutron long counter design for overall efficiency and flat energy response, Monte Carlo simulations were carried out for a variety of detector design parameters using the Monte Carlo N-Particle Extended code. Based on the standard long counter design by McTaggart, moderator diameter, moderator back length, and longitudinal hole diameter were sequentially varied, and the sensitivity of each parameter to the long counter response was systematically analyzed. For each design, simulations were done in the neutron energy range of 1 keV to 10 MeV. From the simulation results, it turned out that out of the three moderator parameters, the moderator diameter is most sensitive for optimizing the long counter response. As the last design parameter, the effect of the central slow-neutron counter was investigated, which showed a significant difference in the response. The investigation of each design parameter gave clear insight on its effect on the long counter response and enabled one to determine the optimum condition.


Assuntos
Simulação por Computador , Método de Monte Carlo , Nêutrons , Aceleradores de Partículas/instrumentação , Radiometria/instrumentação , Algoritmos , Desenho de Equipamento , Humanos , Doses de Radiação
11.
Transplant Proc ; 51(5): 1511-1515, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31155184

RESUMO

BACKGROUND: The autonomic innervation to a liver graft remains lost up to 1 year after liver transplant. Therefore, we investigated the effects of recipients' autonomic nervous activity on the extent of portal hyperperfusion of a partial liver graft in the absence of the autonomic innervation. METHODS: A total of 31 cirrhotic recipients undergoing right lobe living donor liver transplant were analyzed. Following a 10-minute absence of surgical stimulation after hepatic artery and bile duct reconstruction, the electrocardiogram and blood pressure waveforms were recorded for 5 minutes. Low-frequency (LF) and high-frequency (HF) powers and their ratio (LF/HF) were calculated using fast Fourier transform from the electrocardiogram waveform. A decrease in LF/HF represents a shift in sympathovagal balance toward parasympathetic predominance. Then, portal venous (PVF) and hepatic arterial (HAF) blood flows were measured in mL/min per 100 g of liver weight using spectral Doppler ultrasonography. A decrease in their ratio (PVF/HAF) represents attenuation of portal hyperperfusion. RESULTS: The medians of the PVF and HAF were 349 and 27 mL/min/100 g liver weight with interquartile ranges of 272 to 617 mL/min/100 g liver weight and 22 to 41 mL/min/100 g liver weight, respectively, yielding a median of the PVF/HAF of 13.7 (interquartile range, 8.5-21.3). The median of LF/HF was 0.67 (interquartile range, 0.16-1.45). With a reduction in LF/HF, PVF/HAF decreased according to an S-curve regression model between them (PVF/HAF=e2.743+-0.031LF/HF,adjustedR2=0.129,P=0.027). CONCLUSION: A shift in sympathovagal balance toward parasympathetic predominance is associated with attenuation of portal hyperperfusion in a partial liver graft.


Assuntos
Hemodinâmica/fisiologia , Circulação Hepática , Cirrose Hepática/cirurgia , Transplante de Fígado , Sistema Nervoso Parassimpático/fisiologia , Feminino , Humanos , Circulação Hepática/fisiologia , Doadores Vivos , Masculino
12.
Oper Dent ; 44(6): 574-580, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30702408

RESUMO

Two cases of complicated crown fracture of the maxillary incisors were restored using the fragment reattachment technique. Root canal treatment was performed, and the fractured fragment was bonded to the tooth structure using a dentin adhesive system and a flowable composite resin, followed by the insertion of a fiber post using dual-cured resin cement. Reattached fragments have shown reliable prognosis without inflammatory signs around bonded junctions after long-term follow-up.


Assuntos
Colagem Dentária , Fraturas dos Dentes , Resinas Compostas , Coroas , Restauração Dentária Permanente , Seguimentos , Humanos , Cimentos de Resina , Coroa do Dente
13.
J Nutr Health Aging ; 22(10): 1275-1280, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30498837

RESUMO

OBJECTIVES: This study was conducted to determine the cutoff value and efficacy of the EuroQol Visual Analogue Scale (EQ-VAS) for predicting frailty. DESIGN: The EQ-VAS medians (Interquartile Range) were compared and analyzed against the FFI. PARTICIPANTS: The subjects were 1471 older adults aged 70 to 84 years who had completed both EQ-VAS and Fried Frailty index (FFI) in the first baseline year (2016) of the Korean Frailty and Aging Cohort Study. RESULTS: Of the 1471 subjects,600 were classified as robust, 716 as pre-frail, and 155 as frail. The median EQ-VAS scores were 80.00 (20.00) for robust, 75.00 (25.00) for pre-frail, and 60.00 (25.00) for frail subjects.The medians of all five components of the FFI, weight loss (70.00 vs. 80.00), grip strength (70.00 vs. 80.00), exhaustion (70.00 vs. 80.00), walking velocity (70.00 vs. 80.00), and physical activity (70.00 vs. 80.00), were lower in the abnormal groups. We tested the efficacy of EQ-VAS as a diagnostic tool to predict frailty, and the area under the curve of EQ-VAS was 0.71 withthe optimal cut-off value of 72. CONCLUSION: EQ-VAS presented negative correlation with FFI, and the optimal cut off value for frailty was 72. These results suggest that EQ-VAS is a valuable tool for assessing frailty andmay be a good predictor of frailty in Korean elderly population.


Assuntos
Idoso Fragilizado/psicologia , Fragilidade/psicologia , Escala Visual Analógica , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , República da Coreia/epidemiologia
14.
Ann Oncol ; 29(12): 2371-2378, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30346481

RESUMO

Background: The ATLAS trial compared axitinib versus placebo in patients with locoregional renal cell carcinoma (RCC) at risk of recurrence after nephrectomy. Patients and methods: In a phase III, randomized, double-blind trial, patients had >50% clear-cell RCC, had undergone nephrectomy, and had no evidence of macroscopic residual or metastatic disease [independent review committee (IRC) confirmed]. The intent-to-treat population included all randomized patients [≥pT2 and/or N+, any Fuhrman grade (FG), Eastern Cooperative Oncology Group status 0/1]. Patients (stratified by risk group/country) received (1 : 1) oral twice-daily axitinib 5 mg or placebo for ≤3 years, with a 1-year minimum unless recurrence, occurrence of second primary malignancy, significant toxicity, or consent withdrawal. The primary end point was disease-free survival (DFS) per IRC. A prespecified DFS analysis in the highest-risk subpopulation (pT3, FG ≥ 3 or pT4 and/or N+, any T, any FG) was conducted. Results: A total of 724 patients (363 versus 361, axitinib versus placebo) were randomized from 8 May 2012, to 1 July 2016. The trial was stopped due to futility at a preplanned interim analysis at 203 DFS events. There was no significant difference in DFS per IRC [hazard ratio (HR) = 0.870; 95% confidence interval (CI) : 0.660-1.147; P = 0.3211). In the highest-risk subpopulation, a 36% and 27% reduction in risk of a DFS event (HR; 95% CI) was observed per investigator (0.641; 0.468-0.879; P = 0.0051), and by IRC (0.735; 0.525-1.028; P = 0.0704), respectively. Overall survival data were not mature. Similar adverse events (AEs; 99% versus 92%) and serious AEs (19% versus 14%), but more grade 3/4 AEs (61% versus 30%) were reported for axitinib versus placebo. Conclusions: ATLAS did not meet its primary end point; however, improvement in DFS per investigator was seen in the highest-risk subpopulation. No new safety signals were reported. Trial registration number: NCT01599754.


Assuntos
Antineoplásicos/administração & dosagem , Axitinibe/administração & dosagem , Carcinoma de Células Renais/terapia , Neoplasias Renais/terapia , Recidiva Local de Neoplasia/prevenção & controle , Administração Oral , Idoso , Antineoplásicos/efeitos adversos , Axitinibe/efeitos adversos , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Quimioterapia Adjuvante/métodos , Intervalo Livre de Doença , Método Duplo-Cego , Esquema de Medicação , Feminino , Seguimentos , Humanos , Análise de Intenção de Tratamento , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Nefrectomia , Placebos/administração & dosagem , Placebos/efeitos adversos
15.
Br J Anaesth ; 121(2): 483-489, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30032889

RESUMO

BACKGROUND: Emergence delirium is a behavioural disturbance after general anaesthesia in children that can distress patients, parents, and primary caregivers. We hypothesised that listening to the mother's recorded voice can reduce ED compared with listening to a stranger's recorded voice. METHODS: This prospective, double-blind, randomised study was conducted in 2- to 8-yr-old patients who had undergone general anaesthesia. Sixty-six patients were randomly assigned to listen to either the mother's voice (Group M, n=33) or a stranger's voice (Group S, n=33). The primary outcome was the initial paediatric assessment of emergence delirium (PAED) score on arrival at a postanaesthesia care unit (PACU). Other outcomes were the incidence of emergence delirium; Watcha, PAED, and pain scores; PACU stay time; durations between cessation of anaesthetics and bispectral index (BIS) levels of 60, 70, and 80; eye opening time; extubation time; and total consumption of analgesics during the PACU stay. RESULTS: The mother's voice reduced the initial PAED score compared with a stranger's voice [mean (standard deviation), 9.8 (2.5) vs 12.5 (4.1); P=0.002]. The incidence of emergence delirium during the PACU stay was higher in Group S than in Group M [60.6% vs 24.2%, odds ratio (95% confidence interval): 4.88 (1.7-13.9); P=0.006]. The BIS >60 time was shorter in Group M than in Group S (P=0.006). CONCLUSIONS: The mother's voice reduced emergence delirium scores and the incidence of emergence delirium in paediatric patients compared with a stranger's voice after general anaesthesia. CLINICAL TRIAL REGISTRATION: NCT 02955680.


Assuntos
Anestesia Geral/métodos , Delírio do Despertar/prevenção & controle , Mães/psicologia , Voz , Período de Recuperação da Anestesia , Anestesia Geral/efeitos adversos , Criança , Pré-Escolar , Cuidados Críticos , Método Duplo-Cego , Delírio do Despertar/epidemiologia , Delírio do Despertar/psicologia , Feminino , Humanos , Incidência , Tempo de Internação , Masculino , Medição da Dor , Estudos Prospectivos
16.
Radiat Res ; 187(1): 42-49, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28001909

RESUMO

During space missions, astronauts are exposed to a stream of energetic and highly ionizing radiation particles that can suppress immune system function, increase cancer risks and even induce acute radiation syndrome if the exposure is large enough. As human exploration goals shift from missions in low-Earth orbit (LEO) to long-duration interplanetary missions, radiation protection remains one of the key technological issues that must be resolved. In this work, we introduce the NEUtron DOSimetry & Exploration (NEUDOSE) CubeSat mission, which will provide new measurements of dose and space radiation quality factors to improve the accuracy of cancer risk projections for current and future space missions. The primary objective of the NEUDOSE CubeSat is to map the in situ lineal energy spectra produced by charged particles and neutrons in LEO where most of the preparatory activities for future interplanetary missions are currently taking place. To perform these measurements, the NEUDOSE CubeSat is equipped with the Charged & Neutral Particle Tissue Equivalent Proportional Counter (CNP-TEPC), an advanced radiation monitoring instrument that uses active coincidence techniques to separate the interactions of charged particles and neutrons in real time. The NEUDOSE CubeSat, currently under development at McMaster University, provides a modern approach to test the CNP-TEPC instrument directly in the unique environment of outer space while simultaneously collecting new georeferenced lineal energy spectra of the radiation environment in LEO.


Assuntos
Planeta Terra , Nêutrons , Monitoramento de Radiação/instrumentação , Voo Espacial , Astronautas , Radiação Cósmica/efeitos adversos , Desenho de Equipamento , Humanos , Nêutrons/efeitos adversos , Exposição à Radiação/análise , Proteção Radiológica
17.
Poult Sci ; 96(3): 710-716, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27697932

RESUMO

The use of chlorella as an immune stimulant to enhance nonspecific host defense mechanisms or as an antimicrobial to inhibit bacterial growth has been reported. Thus, the aim of the present study was to clarify the effect of recombinant chlorella supplementation on growth performance, meat quality, and the blood profile, excreta microflora, and nutrient digestibility in broilers. A total of 375 one-day-old ROSS 308 broilers (male and female) were allotted to 5 dietary treatments using 5 cages with 15 chicks per cage. Treatments were: 1) NC, basal diet supplemented with 1.0% E. coli fermented liquor (EFL); 2) PC1, 0.2% EFL with chlorella; 3) PC2, 1.0% EFL with chlorella; 4) T1, 0.2% EFL with chlorella (anti-viral); and 5) T2, 1.0% EFL with chlorella (anti-viral). The broilers in the T2 treatment groups showed higher body weight gain (BGW) by 2.55% (P < 0.01) and lower feed conversion ratio (FCR) by 2.75% (P < 0.05) compared with those fed the control NC treatment group. Moreover, the blood contents of blood urea nitrogen (BUN), creatinine, and IgA in the broilers of the T2 treatment group were significantly increased by 28.12, 23.07, and 29.72%, respectively -more than those found in the broilers of the NC treatment group (P < 0.01). In contrast, the LDL/C in the blood from the animals in the T2 treatment group was significantly decreased by 23.23% - more than that in the blood from the NC broilers (P < 0.05). Based on these results, we suggest that the dietary supplementation of broilers with recombinant chlorella could improve their growth performance, increase the concentration of IgA and apparently metabolizable nitrogen in the blood, and decrease ammonia emissions. Therefore, our findings have important implications for the effect of recombinant chlorella supplementation through increasing the concentration of IgA and the level of metabolizable nitrogen.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/fisiologia , Chlorella , Suplementos Nutricionais , Digestão/fisiologia , Fezes/microbiologia , Carne/normas , Ração Animal/análise , Animais , Galinhas/sangue , Galinhas/crescimento & desenvolvimento , Galinhas/microbiologia , Chlorella/química , Chlorella/genética , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Masculino , Carne/análise , Distribuição Aleatória , Anticorpos de Cadeia Única
18.
Benef Microbes ; 7(5): 731-737, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27824272

RESUMO

Treatment and prevention methods for non-steroidal anti-inflammatory drug-induced enteropathy have not yet been established. We tested the preventive effects of s-pantoprazole sodium trihydrate (PAN), polaprezinc (PZ), and probiotics on an indomethacin (Indo)-induced small intestinal injury in a rat model. Rats were randomised into 6 groups to receive: normal saline (control), Indo (6 mg/kg), PZ plus Indo, PAN plus Indo, or probiotics plus Indo (at 108 and 109 cfu/head) for 2 weeks. We measured body weight, food intake, severity of small intestinal damage, haemoglobin (Hb) levels in the small intestinal fluid, intestinal inflammatory cytokines, and a few groups of faecal bacteria. The experimental groups were found to have the following survival rates: 0% for the Indo, PZ, and PAN groups; 50% for both probiotic groups; and 100% for control. Treatment with probiotics of different concentrations reduced small intestinal lesion scores and intestinal fluid Hb as compared with the Indo group, while these parameters did not reduce in the PZ and PAN groups. The anti-inflammatory marker interleukin 10 increased in both probiotic groups. Analysis of a few groups of faecal bacteria revealed that Indo-induced a significant increase in Gram-negative bacteria and decreases in Bifidobacterium and Lactobacillus. Similar changes were also observed in the PZ and PAN groups. However, opposite effects were found in both probiotic groups. The use of probiotics appeared to be beneficial in preventing Indo-induced chronic small intestinal injury.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Antiulcerosos/farmacologia , Indometacina/efeitos adversos , Probióticos/farmacologia , 2-Piridinilmetilsulfinilbenzimidazóis/farmacologia , Animais , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/crescimento & desenvolvimento , Peso Corporal , Carnosina/análogos & derivados , Carnosina/farmacologia , Doença Crônica , Citocinas/metabolismo , Modelos Animais de Doenças , Ingestão de Alimentos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Intestino Delgado/lesões , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Masculino , Compostos Organometálicos/farmacologia , Pantoprazol , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Compostos de Zinco/farmacologia
19.
Physiol Meas ; 37(11): N76-N83, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27710928

RESUMO

The time-dependent behaviour of sodium and chlorine was studied as a spinoff from a study of aluminum in the hand of subjects suffering from Alzheimer's disease and a control group, involving 15 Alzheimer's and 16 control subjects with an age range of 63-89 years. This was achieved using the in vivo neutron activation analysis system developed at McMaster University for the non-invasive measurement of aluminum, where a subject's hand is placed in a beam of accelerator-based thermalized neutrons, which activates elements by neutron capture. Following irradiation, the subject's hand is placed in a detection system comprising 9 NaI(Tl) detectors arranged in a 4π geometry to measure activated elements. The redistribution half-lives of the activation products 24Na and 38Cl from the hand were determined after correction for the physical half-life, by means of sequential analysis of the residual activity in the hand. The kinetic behaviours of sodium and chlorine were best characterized by an exponential function corresponding to the rapidly exchangeable pool. The mean redistribution half-lives from the hand for sodium and chlorine in the control subjects were 40.5 ± 17.4 min and 24.2 ± 8.5 min, respectively. For Alzheimer's disease subjects the mean redistribution half-lives were 58.2 ± 36.1 min for sodium and 33.6 ± 16.7 min for chlorine. There was no significant difference in chlorine and sodium redistribution half-lives between the Alzheimer's disease and control group subjects. These results are promising, given that the irradiation and counting protocol were optimized for the aluminum study, rendering them suboptimal for analyzing other elements and their rate of change with time. Further improvements include optimizing the irradiation protocol, longer counting times, and measuring the activity in the un-irradiated hand in various time intervals following irradiation.


Assuntos
Cloro/metabolismo , Mãos , Sódio/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Análise de Ativação de Nêutrons
20.
J Wound Care ; 25(7): 393-7, 2016 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-27410393

RESUMO

UNLABELLED: Management and treatment of acute severe diabetic foot disease in patients with suboptimal glycaemic control is a critical issue in wound repair. This paper discusses the clinical efficacy of an aggressive surgical intervention combined with targeted use of regenerative medical therapies in limb preservation. Negative pressure wound therapy (NPWT), platelet-rich plasma (PRP), bilayered acellular matrix grafting and split-thickness skin grafting were combined to treat a patient with diabetes, foot necrotising fasciitis and gaseous gangrene. The wound was completely healed. The clinical outcome revealed that a multi-intervention strategy could be effective for large necrotising fasciitis wounds. Early clinical observation, suggests aggresive surgical intervention preserving intact tissue and targeted use of new regenerative technologies can lead to preservation of a limb. DECLARATION OF INTEREST: The authors have received no financial support for the material presented in this study outside of the scope of standard patient care reimbursement. This work was supported by the National Natural Science Foundation of China (NO. 81500596) awarded to Dr Wuquan Deng.


Assuntos
Pé Diabético/terapia , Tratamento de Ferimentos com Pressão Negativa , Plasma Rico em Plaquetas , Transplante de Pele , Cicatrização/fisiologia , Derme Acelular , Adulto , China , Humanos , Masculino , Resultado do Tratamento
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