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1.
J Dairy Sci ; 106(12): 8357-8367, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37641250

RESUMO

Several studies have been focused on the effect of milk protein genetic variants on milk physicochemical properties and functionality in recent years. ß-casein, an important protein related to milk processibility, has been reported to have 2 main genetic variants A1 and A2, for which cows may be homozygous or heterozygous. In this study, several physicochemical properties of milk with ß-casein variants A1A1, A1A2, and A2A2 from 3 collection occasions were analyzed. Higher manganese content and lower pH were found to be associated with the A1A1 variant compared with the other 2 genotypes. Better rennet and acid coagulation were found in A1A1 milk compared with A1A2 and A2A2 milk (although P > 0.05), whereas A2A2 milk was more stable to creaming compared with the other 2 genotypes, which may be linked to its smaller fat globule size. Thus, milk from cows with A1A1 genotype could be preferable for cheese making, while that with A2A2 variant can be used in formulations requiring good stability against creaming, and for example, yogurt making, where the softer yogurt texture may be easier to digest.


Assuntos
Caseínas , Leite , Feminino , Bovinos , Animais , Caseínas/química , Leite/química , Proteínas do Leite/análise , Genótipo , Heterozigoto
2.
Chemosphere ; 179: 387-394, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28390306

RESUMO

The Grand Canal, also known as the Beijing-Hangzhou Grand Canal, is a UNESCO World Heritage Site and the longest canal in the world. It is an important trunk line of the South-to-North Water Diversion Project in China. The contamination status and spatial distributions of perfluoroalky substances (PFASs) in waters of the Grand Canal were investigated. The total concentrations of PFASs (∑PFASs) range from 7.8 ng/L to 218.0 ng/L, with high ∑PFASs occurring in the southern part of the Grand Canal which is located in a highly urbanized and economically developed region. The dominance of PFOA showed a decreasing trend toward north while shorter chain homologue proportions increased in the northern part of the Canal which mainly traverses underdeveloped and rural areas in Eastern China. Positive correlations were observed between ∑PFASs and the population density as well as GDP per capita. Intersection with large rivers may affect the contamination levels and composition of PFASs in the water of the Grand Canal near the intersection sites.


Assuntos
Monitoramento Ambiental , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Pequim , Caprilatos , China , Rios/química , Urbanização , Água/química
3.
Zhonghua Er Ke Za Zhi ; 55(4): 288-293, 2017 Apr 02.
Artigo em Chinês | MEDLINE | ID: mdl-28441826

RESUMO

Objective: To explore clinical characteristics, treatment, and prognosis of a family with childhood-onset rapid-onset dystonia parkinsonism (RDP) caused by ATP1A3 gene mutation and review literatures. Method: The clinical data of a RDP child, his brother and mother had been analyzed retrospectively. This family was admitted to Xiangya Hospital in January 2016. DNA samples were analyzed by the next-generation sequencing and confirmed by Sanger sequencing. Related literature from PubMed, Online Mendelian Inheritance in Man (OMIM), CNKI and Wanfang databases to date (up to October 2016) with"Rapid-onset dystonia-parkinsonism""RDP""DYT12" as key words was reviewed. Result: The proband boy was three years and four months old (April 2015) when he had the first attack of the disease. After a febricity, he suddenly acquired acute aphasia and limb movement disorder. Rehabilitation therapy and supportive treatment made his speech gradually recovered but still slurred. However, his abnormal walking posture still existed. Nine months later (January 2016, 4 years and one months old), symptoms including aphasia, dysphagia, and weakness with rostrocaudal gradient reoccured after fever. The disease progressed to the critical condition within 24 hours. He"seizured" four times with tonic spasms of limbs but without loss of consciousness. Family history showed his grandparents were consanguineous marriage. His mother and brother also developed abnormal gait and dysarthria after an infection before primary school age. Their symptoms improved gradually without relapsing. However, they did not recover entirely with mild intellectual disability. His mother had a healthy brother and sister. This proband had no other siblings but the brother. Heterozygous missense mutation p. R756H in ATP1A3 gene was detected in this proband, his mother and his brother. This mutation had been reported pathogenically related to RDP, and it located in highly conserved gene region. Benzodiazepine was used for the proband and his brother, with the proband being improved better although not completely. Meanwhile, benzodiazepine had no significant effect on his mother because of poor compliance. This is the first case report of RDP in China. The mutations of ATP1A3 have been previously reported in 51 patients including 6 large families and 16 other unrelated patients. A total of 14 different mutations in ATP1A3 gene with RDP have been reported to date, including 12 missense mutations, a 3-bp in-frame deletion, and a 3-bp in-frame insertion. The sporadic cases all had the typical clinical phenotypes of RDP, such as the abrupt onset of dysarthria, dysphagia, limb dystonia with bradykinesia, and postural instability. The symptoms of bulbar and arms were much more obvious. It was hard to diagnose RDP in a family because some patients had typical symptoms of RDP, while the others might experience from mild symptoms to no symptoms, which might be related to incomplete penetrance of RDP. Two cases carrying the same mutation as our patients also presented some overlapping phenotypes. Conclusion: The p. R756H heterozygous mutation in ATP1A3 gene is the pathogenic mutation of RDP, analysis of genotype-phenotype correlations of RDP will be very important and meaningful.


Assuntos
Distúrbios Distônicos/genética , ATPase Trocadora de Sódio-Potássio/genética , Pré-Escolar , China , Distonia , Extremidades , Feminino , Heterozigoto , Humanos , Masculino , Transtornos dos Movimentos , Mutação , Fenótipo , Irmãos
4.
Zhonghua Er Ke Za Zhi ; 55(2): 115-119, 2017 Feb 02.
Artigo em Chinês | MEDLINE | ID: mdl-28173649

RESUMO

Objective: To explore the association between the phenotype and KCNB1 gene mutation. Method: Clinical information including physical features, laboratory and genetic data of one patient of mental retardation with refractory epilepsy from Department of Pediatrics, Xiangya Hospital in January 2016 was analyzed. This patient was discovered to have KCNB1 gene mutations through whole exome sequencing. Relevant information about KCNB1 gene mutation was searched and collected from Pubmed, CNKI, Human Gene Mutation Database(HGMD) and Online Mendelian Inheritance in Man(OMIM). Searching was done using "KCNB1" as a keyword. Result: A 3.5 years old boy who visited our hospital firstly at the age of 2 years because of development delay came for follow up as he developed seizures.The forms included tonic, clonic seizures and spasm. The condition became more severe 10 months later. Electroencephalogram(EEG) showed high frequency discharge (>85%). He had poor response to multiple anti-epileptic drugs, methylprednisolone and ketogenic diet. At the age of 3, he started to have mental regression. Whole exome-sequencing study (trios) identified a novel heterozygous mutation c. G1136T (p.G379V) in KCNB1, which is not available in the databases mentioned above. This is the first case report of KCNB1 gene mutation in China. Eight cases have been reported so far worldwide and all of them were diagnosed with refractory epilepsy. Those 8 reported cases of encephalopathy were all due to de novo mutation. Conclusion: The main clinical features of patients with KCNB1 mutations include severe to profound intellectual disability, intractable seizures, hypotonia and regression of cognition and motor activity which lead to poor prognosis.


Assuntos
Epilepsia/genética , Deficiência Intelectual/complicações , Mutação , Canais de Potássio Shab/genética , Pré-Escolar , China , Comorbidade , Deficiências do Desenvolvimento , Dieta Cetogênica , Eletroencefalografia , Epilepsia/complicações , Humanos , Masculino , Fenótipo , Convulsões
5.
J Environ Radioact ; 148: 59-66, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26114808

RESUMO

Activities of atmospheric aerosols, bulk deposition fluxes, and undisturbed soil inventories of (7)Be were investigated in China's East Asian monsoon zone at various latitudes ranging from 23.8°N to 43.5°N. The annual latitudinal distributions of (7)Be concentrations in aerosols follow a distribution pattern which looks similar to a normal distribution with the maxima occurring in the mid-latitude region. Simultaneous measurements of (7)Be at various latitudes suggest that atmospheric circulation may play an important role in the latitudinal distributions of (7)Be in surface air. Latitude and wet precipitation are the main factors controlling the bulk (7)Be depositional fluxes. Significant seasonal variations in (7)Be depositional fluxes in Beijing, a mid-latitude city, were observed with the highest flux in summer and the lowest in winter, whereas less seasonality were found in the high- and the low-latitude cities. The highest (7)Be inventory in undisturbed soils in summer also occurred at a mid-latitudinal area in the East Asian monsoon zone. Precipitation is the main factor controlling the (7)Be soil inventory in Qingdao with the highest values occurring in autumn followed by summer.


Assuntos
Poluentes Radioativos do Ar/análise , Berílio/análise , Monitoramento de Radiação , Radioisótopos/análise , Poluentes Radioativos do Solo/análise , Aerossóis/análise , China , Geografia
6.
Brain Res ; 1407: 90-6, 2011 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-21741032

RESUMO

We characterized the effect of acute ischemic stroke on the activation of the hypothalamic-pituitary-adrenal (HPA) axis and evaluated the role of glucocorticoids (GC) in the clinical outcome following ischemic stroke. Male spontaneous hypertensive rats underwent permanent middle cerebral artery occlusion (PMCAO) and developed a cortical infarct. At 4h post-PMCAO or sham operation, serum levels of ACTH and corticosterone (CS) were elevated 5 and 4 fold respectively as compared to controls and then returned to basal levels at 24h post surgery. In these experimental groups we found also a significant depletion of median eminence (ME)-CRH(41). In adrenalectomized (Adx) rats that underwent PMCAO the degree of motor disability and infarct volume was similar to that of intact rats. Administration of dexamethasone (Dex) to Adx-PMCAO rats significantly improved the motor disability and decreased the infarct volume. However, in sham-Adx with PMCAO, Dex had no effect on these two parameters. In rats with PMCAO or sham-PMCAO, brain production of PGE(2) was significantly increased. This effect was further enhanced in Adx-PMCAO rats and significantly inhibited by Dex. In conclusion, activation of the HPA axis following PMCAO is due to stress induced by surgery. This activation is mediated by hypothalamic CRH(41). Absence of endogenous GC or administration of Dex in naïve rats does not alter motor and pathological parameters in the acute stage following PMCAO. In contrast, administration of Dex significantly improved the outcome following cerebral ischemia in Adx rats which may be due to increased glucocorticoid receptors. Brain production of PGE(2) does not play an important role in the pathophysiology of the acute phase of cerebral ischemia.


Assuntos
Córtex Suprarrenal/fisiologia , Isquemia Encefálica/fisiopatologia , Glucocorticoides/fisiologia , Glucocorticoides/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Acidente Vascular Cerebral/fisiopatologia , Adrenalectomia , Hormônio Adrenocorticotrópico/sangue , Animais , Anti-Inflamatórios/uso terapêutico , Isquemia Encefálica/complicações , Corticosterona/sangue , Hormônio Liberador da Corticotropina/metabolismo , Dexametasona/uso terapêutico , Dinoprostona/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Hipotálamo/metabolismo , Infarto da Artéria Cerebral Média/etiologia , Infarto da Artéria Cerebral Média/fisiopatologia , Coxeadura Animal/etiologia , Coxeadura Animal/patologia , Masculino , Eminência Mediana/fisiologia , Fragmentos de Peptídeos/metabolismo , Ratos , Ratos Endogâmicos SHR , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/fisiologia , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
7.
Science ; 332(6026): 213-6, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21474754

RESUMO

In addition to its search for extrasolar planets, the NASA Kepler mission provides exquisite data on stellar oscillations. We report the detections of oscillations in 500 solar-type stars in the Kepler field of view, an ensemble that is large enough to allow statistical studies of intrinsic stellar properties (such as mass, radius, and age) and to test theories of stellar evolution. We find that the distribution of observed masses of these stars shows intriguing differences to predictions from models of synthetic stellar populations in the Galaxy.

8.
Magn Reson Med ; 46(6): 1130-5, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11746579

RESUMO

Spiral acquisitions are used in fast cardiac imaging because they traverse k-space efficiently and minimize flow artifacts. A variable pitch logarithmic spiral trajectory is designed to critically sample the low-frequency region in k-space and gradually undersample the high-frequency region. An approximate analytical expression for the trajectory provides a fast means to calculate the gradient waveforms and the sampled data points. A numerical method is introduced based on the trajectory curvature and the rate of change in the gradient magnitude with time for the composite Archimedean-logarithmic trajectory. The pulse sequence is implemented and images are acquired on phantoms and human hearts. The images show improved image resolution and some improvement in image quality as a result of increased extent in k-space and reduction in aliasing artifacts, respectively.


Assuntos
Coração/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Artefatos , Humanos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas
9.
J Magn Reson Imaging ; 7(6): 1166-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9400865

RESUMO

Timing inaccuracies between the even and odd echoes lead to the formation of Nyquist ghosts in conventional (blipped) echo-planar imaging (EPI). A fast radial scanning method based on the linogram sampling geometry was designed and implemented. No ghosting effects are seen with this scheme, and correction for timing inaccuracies is performed using simple postprocessing steps before reconstruction.


Assuntos
Imagem Ecoplanar/métodos , Artefatos , Modelos Teóricos
10.
Magn Reson Med ; 38(2): 337-41, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9256116

RESUMO

An alternate scheme for linogram image reconstruction, which is more logical from the viewpoint of its applicability to MRI data, is presented here. As a result, an intermediate step for this method, the direct Fourier method (DFM) gives the same results as the earlier developed general reconstruction algorithm labeled as the linogram method (LM). However, the two differ in the pathways taken to the solution. As a result, an intermediate step for DFM corresponds directly with the geometry of linogram data collected for MRI, in contrast to the LM reconstruction. The two reconstruction methods are delineated within the context of MRI data reconstruction, and applied to reconstruct images from linogram spin-echo data of a physical phantom, obtained on a clinical 1.5 T scanner.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Análise de Fourier
11.
Magn Reson Med ; 37(2): 275-84, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9001153

RESUMO

Chemical shift differences, field inhomogeneity, and gradient nonlinearity result in artifacts in magnetic resonance imaging. Three artifacts are characterized for linogram imaging and it is shown that, based on computer simulations and theory, linogram MRI behaves similarly to 2DFT. A correction technique similar to a scheme for 2DFT imaging based on the Dixon technique and coordinate transform methods is proposed. The algorithm is applied to correct for field inhomogeneity and gradient nonlinearity-induced artifacts in both simulations and images of a clinical phantom. The results show good correlation with the theory. It is concluded that linogram imaging offers certain attractive features of both 2DFT and PR imaging techniques, and is a potentially viable alternative to PR imaging in the presence of field inhomogeneity.


Assuntos
Artefatos , Imageamento por Ressonância Magnética/métodos , Tecido Adiposo , Algoritmos , Água Corporal , Encéfalo/anatomia & histologia , Simulação por Computador , Sulfato de Cobre , Análise de Fourier , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador , Modelos Teóricos , Imagens de Fantasmas , Prótons
12.
Med Phys ; 23(2): 251-62, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8668107

RESUMO

Motion results in various artifacts such as blurring and streaks in clinical imaging of subjects based on reconstruction from projections. We model subject motion-induced artifacts due to scaling, translational and rotational motion. A correction algorithm based on the Ludwig-Helgason consistency conditions is derived here. These conditions are satisfied whenever the projection data are consistent. We apply the algorithm to simulated data collected on linogram (LR) and projection reconstruction (PR) geometries, and to real PR geometry data, in magnetic resonance imaging (MRI). The results show that motion-induced in-plane, interview artifacts can be reduced with application of the algorithm. The algorithm is general enough to be applied to certain other cases arising in tomographic imaging.


Assuntos
Artefatos , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Cobre , Sulfato de Cobre , Humanos , Matemática , Movimento , Soluções , Água
14.
Psychopharmacology (Berl) ; 78(3): 225-9, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6818579

RESUMO

In the present study the effects of chronic treatment of pregnant rats with diazepam on the physical and behavioral development of their offspring were investigated. Rats that were diazepam-exposed prenatally were compared to age-matched controls in terms of the following: number of littermates; birth weight and weight gain until weaning: motor development and coordination; simple motor learning; open field activity; performance on learning tasks of varying complexity; retention of these tasks. Nulliparous Wistar rats were injected s.c. for 16 days of their pregnancy was either 2.5, 5, of 10 mg/kg diazepam or an equal volume of vehicle. Prenatal diazepam treatment did not alter litter size, birth weight, or the righting reflex, but seemed to retard early motor development transiently. Diazepam pups showed longer latencies and less rearing in the open field. There were no differences between animals exposed to drug and vehicle in simple motor learning or in acquiring a simple successive discrimination task. However, there were significant dose-dependent differences on a complex six-choice simultaneous discrimination learning task, the diazepam-exposed rats making more errors and taking more time to reach the goal. A significant difference was seen again between diazepam- and vehicle-exposed rats on the retention test 10 days later. The results indicate that diazepam administered to pregnant rats has long-range effects on the behavior of the offspring, some becoming manifest even in maturity.


Assuntos
Comportamento Animal/efeitos dos fármacos , Diazepam/farmacologia , Efeitos Tardios da Exposição Pré-Natal , Animais , Peso Corporal/efeitos dos fármacos , Aprendizagem por Discriminação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Comportamento Exploratório/efeitos dos fármacos , Feminino , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Destreza Motora/efeitos dos fármacos , Gravidez , Ratos , Ratos Endogâmicos , Retenção Psicológica/efeitos dos fármacos
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