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Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(9): 873-879, 2021 Sep 09.
Artigo em Chinês | MEDLINE | ID: mdl-34496535


Objective: To record occlusal contact of primary dentition at maximal intercuspal position in children with individual normal occlusion. Methods: A total of 57 children were recruited from patients of the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology. Inclusion criteria were that the subjects were 3-5 years old with no visually detectable caries or pupal and periapical diseases, had complete primary dentition, had individual normal occlusion, had normal function of craniofacial system, were medically healthy, could cooperate with sampling and had obtained written informed consent from the parents or guardians. Finally, forty-seven children aged 3 to 5 years old were enrolled, including 24 males and 23 females. The age, height and weight of all subjects were (4.1±0.7) years old (ranging 3.0-5.8 years old), (103.7±7.2) cm (ranging 90-120 cm) and (17.1±2.5) kg (ranging 12.5-22.5 kg), respectively. Occlusal abilities such as occlusal contact area, average bite pressure, maximum bite pressure, maximum bite force and occlusal balance were measured with Dental Prescale Ⅱ system. Results: Maximum bite force and occlusal contact area at intercuspal position in children with primary dentition were (567.40±223.84) N (ranging 226.7-1 154.6 N) and (18.56±6.54) mm2 (ranging 8.4-41.2 mm2), respectively. There was a significantly strong correlation between maximum bite force and occlusal contact area (r=0.954, P<0.01). Height and weight of children were also positively correlated with their maximum bite force (r=0.397, P=0.022 and r=0.453, P=0.008, respectively). Maximum occlusal bite force and contact occlusal area of boys [(651.80±224.34) N and (20.77±6.97) mm2] were significantly higher and larger than those of girls [(479.34±190.45) N and (16.25±5.27) mm2] (P<0.05). Thirty-two of all 47 children had one occlusal contact point with maximum bite pressure, mostly locating within the primary molar region. Bite forces of anterior and posterior teeth of primary dentition were (124.12±56.99) N and (450.11±205.09) N, respectively, about (21.82±11.40)% and (71.80±21.35)% of maximum bite force of the whole primary dentition. All of the occlusal balance points located in posterior teeth regions. Occlusal contacts were observed at both anterior and posterior teeth of primary dentition with individual normal occlusion. Conclusions: There was a great variation of maximum bite forces of primary dentitions at intercuspal position of children with individual normal occlusion. Maximum bite force of primary dentition was significantly correlated with occlusal contact area, height and weight of children. Occlusal contact points with maximum bite pressure and occlusal bite balance points of primary dentitions mostly located in primary molar regions.

Força de Mordida , Oclusão Dentária , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Dente Molar , Dente Decíduo
J Dairy Sci ; 100(7): 5329-5342, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28501402


An experiment was conducted to uncover the effects of increasing dietary grain levels on expression of thiamine transporters in ruminal epithelium, and to assess the protective effects of thiamine against high-grain-induced inflammation in dairy cows. Six rumen-fistulated, lactating Holstein dairy cows (627 ± 16.9 kg of body weight, 180 ± 6 d in milk; mean ± standard deviation) were randomly assigned to a replicated 3 × 3 Latin square design trial. Three treatments were control (20% dietary starch, dry matter basis), high-grain diet (HG, 33.2% dietary starch, DM basis), and HG diet supplemented with 180 mg of thiamine/kg of dry matter intake. On d 19 and 20 of each period, milk performance was measured. On d 21, ruminal pH, endotoxic lipopolysaccharide (LPS), and thiamine contents in rumen and blood, and plasma inflammatory cytokines were detected; a rumen papillae biopsy was taken on d 21 to determine the gene and protein expression of toll-like receptor 4 (TLR4) signaling pathways. The HG diet decreased ruminal pH (5.93 vs. 6.49), increased milk yield from 17.9 to 20.2 kg/d, and lowered milk fat and protein from 4.28 to 3.83%, and from 3.38 to 3.11%, respectively. The HG feeding reduced thiamine content in rumen (2.89 vs. 8.97 µg/L) and blood (11.66 vs. 17.63 µg/L), and the relative expression value of thiamine transporter-2 (0.37-fold) and mitochondrial thiamine pyrophosphate transporter (0.33-fold) was downregulated by HG feeding. The HG-fed cows exhibited higher endotoxin LPS in rumen fluid (134,380 vs. 11,815 endotoxin units/mL), and higher plasma concentrations of lipopolysaccharide binding protein and pro-inflammatory cytokines when compared with the control group. The gene and protein expression of tumor necrosis factor α (TNFα), IL1B, and IL6 in rumen epithelium increased when cows were fed the HG diet, indicating that local inflammation occurred. The depressions in ruminal pH, milk fat, and protein of HG-fed cows were reversed by thiamine supplementation. Thiamine supplementation increased thiamine contents in rumen and blood, and also upregulated the relative expression of thiamine transporters compared with the HG group. Thiamine supplementation decreased ruminal LPS (49,361 vs. 134,380 endotoxin units/mL) and attenuated the HG-induced inflammation response as indicated by a reduction in plasma IL6, and decreasing gene and protein expression of pro-inflammatory cytokines in rumen epithelium. Western bottling analysis showed that thiamine suppressed the protein expression of TLR4 and the phosphorylation of nuclear factor kappa B (NFκB) unit p65. In conclusion, HG feeding inhibits thiamine transporter expression in ruminal epithelium. Thiamine could attenuate the epithelial inflammation during high-grain feeding, and the protective effects may be due to its ability to suppress TLR4-mediated NFκB signaling pathways.

Gastrite/veterinária , Proteínas de Membrana Transportadoras/metabolismo , Rúmen/metabolismo , Tiamina/administração & dosagem , Tiamina/metabolismo , Animais , Bovinos , Dieta , Epitélio/metabolismo , Feminino , Fermentação , Concentração de Íons de Hidrogênio , Lactação , Leite/metabolismo
Leukemia ; 23(2): 235-44, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19151784


Cell surface proteins can play important roles in cancer pathogenesis. Comprehensive understanding of the surface protein expression patterns of tumor cells and, consequently, the pathogenesis of tumor cells depends on molecular probes against these proteins. To be used effectively for tumor diagnosis, classification and therapy, such probes would be capable of specific binding to targeted tumor cells. Molecular aptamers, designer DNA-RNA probes, can address this challenge by recognizing proteins, peptides and other small molecules with high affinity and specificity. Through a process known as cell-based SELEX, we used live acute myeloid leukemia (AML) cells to select a group of DNA aptamers, which can recognize AML cells with dissociation constants (Kd's) in the nanomolar range. Interestingly, one aptamer (KH1C12) compared with two control cell lines (K562 and NB4) showed significant selectivity to the target AML cell line (HL60) and could recognize the target cells within a complex mixture of normal bone marrow aspirates. The other two aptamers KK1B10 and KK1D04 recognize targets associated with monocytic differentiation. Our studies show that the selected aptamers can be used as a molecular tool for further understanding surface protein expression patterns on tumor cells and thus providing a foundation for effective molecular analysis of leukemia and its subcategories.

Antígenos de Neoplasias/metabolismo , Aptâmeros de Nucleotídeos , Leucemia Mieloide Aguda/diagnóstico , Técnica de Seleção de Aptâmeros , Antígenos de Superfície/metabolismo , Aptâmeros de Nucleotídeos/farmacocinética , Linhagem Celular Tumoral , Humanos , Leucemia Mieloide Aguda/patologia , Técnicas de Sonda Molecular , Ligação Proteica , Sensibilidade e Especificidade
Aviat Space Environ Med ; 62(5): 403-6, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2053903


A series of experiments were conducted on guinea pigs to study the protective effect of hyperbaric oxygen (HBO) on hearing during chronic repeated noise exposure. A 1/3 octave band of noise centered at 1000 Hz was used (126 dB SPL, 1 h daily for 5 d; or 108 dB SPL, 1 h daily, 5 d/week for 4 weeks). Some groups of animals were treated with HBO (2-3 ATA, 1 h duration) before noise exposure. The results indicate that inhalation of HBO (every other day) can markedly reduce noise-induced threshold shift and relieve cochlear damage. The mechanism responsible for HBO protection against noise-induced hearing damage is discussed.

Perda Auditiva Provocada por Ruído/prevenção & controle , Oxigenação Hiperbárica , Animais , Audiometria de Resposta Evocada , Limiar Auditivo , Cobaias , Células Ciliadas Auditivas/patologia , Perda Auditiva Provocada por Ruído/patologia , Perda Auditiva Provocada por Ruído/fisiopatologia , Masculino
Anat Embryol (Berl) ; 175(4): 517-20, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3578828


The projections from the dentate nucleus to the reticular formation of the brain stem in rabbit have been examined by means of the Fink-Heimer technique. The fibers arising from the dentate nucleus primarily project to the reticular formation via the contralateral and ipsilateral descending limbs of the brachium conjunctivum. The descending fibers project bilaterally to the parvocellular reticular nucleus, the ventral reticular nucleus, the gigantocellular reticular nucleus, the nucleus raphe magnus, the oral and caudal pontine reticular nuclei, and the reticulo-tegmental nucleus.

Núcleos Cerebelares/ultraestrutura , Fibras Nervosas/ultraestrutura , Coelhos/anatomia & histologia , Formação Reticular/ultraestrutura , Animais , Degeneração Neural , Vias Neurais/ultraestrutura
Anat Embryol (Berl) ; 175(4): 521-6, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2437832


By retrograde transport of horseradish peroxidase the reticulocerebellar projections were examined in twenty-six rabbits. After injections in the cerebellum retrogradely labeled neurons were more numerous in the caudal reticular formation (ventral and gigantocellular reticular nuclei) than in its rostral part (caudal and oral pontine reticular nuclei). The labeled cells were of all sizes, large, medium-sized and small. Giant cells were labeled only after injections in the posterior lobe vermis. After injections in the anterior lobe, the posterior vermis, the fastigial nucleus and the flocculus, retrogradely labeled neurons were found bilaterally in the ventral reticular nucleus, the gigantocellular reticular nucleus and the caudal pontine reticular nucleus. Some cases with posterior vermal and fastigial injections in addition showed labeled neurons bilaterally in the oral pontine reticular nucleus. There were no major side differences. The cases with injections in the anterior part of the paramedian lobule gave rise to only a few labeled cells in the gigantocellular reticular nucleus. Negative findings were consistently made in the mesencephalic reticular formation.

Cerebelo/citologia , Coelhos/anatomia & histologia , Formação Reticular/citologia , Animais , Transporte Axonal , Peroxidase do Rábano Silvestre , Vias Neurais/citologia , Neurônios/citologia