Co-ordination of cough and swallow in vivo and in silico

Coughing and swallowing are airway-protective behaviours. The pharyngeal phase of swallowing prevents aspiration of oral material (saliva, food and liquid) by epiglottal movement, laryngeal adduction and clearing of the mouth and pharynx. Coughing is an aspiration-response behaviour that removes material from the airway. Co-ordination of these behaviours is vital to protect the airway from further aspiration-promoting events, such as a swallowing during the inspiratory phase of coughing. The operational characteristics, primary strategies and peripheral inputs that co-ordinate coughing and swallowing are unknown. This lack of knowledge impedes understanding and treatment of deficits in airway protection, such as the co-occurrence of dystussia and dysphagia common in Parkinson's and Alzheimer's diseases, as well as stroke.     

Incorporation and Disappearance of Sulfate in Different Regions of Mouse and Rat Costal Cartilage in vivo and in vitro

A rapid and simple method for liquid scintillation counting of ³³S-sulfate in biological tissues is described. Sulfate incorporation per mg dry weight into selected lateral, medial and intermediate regions of ribs was studied using costal cartilage from rats and mice. In vitro, cartilage pieces embracing the osteochondral junction had 2–4 times larger incorporation rate than the remaining homogeneous parts of the ribs, both if entire rib cages or stripped and diced cartilage were incubated. After in vivo injection to rats and mice the incorporation rates of sulfate into the region of the osteochondral junction was 2.6 times that found in “resting” cartilage in rats and 4.4 times in mice. The ³⁵S-sulfate uptake in the ribs per mg dry cartilage diminished in the caudal direction. Growth of the chest cage was mainly a longitudinal growth of the bony segments. Marked differences in the disappearance rates of previously incorporated sulfate were found in different regions along the rib. Rapid sulfate disappearance was found in the bony segment which, however, had incorporated only one seventh of the amount per mg taken up by “resting” cartilage. The “resting” cartilage segments exhibited a steady slow disappearance rate for sulfate and the osteochondral junction region consisting of several differently active tissues showed a rapid sulfate disappearance in the beginning followed by a slow clearance after 2 weeks similar to that of “resting” cartilage. The necessity of careful selection of costal cartilage samples with respect to regional differences is emphasized.     

An in vivo and in vitro study of selenium deficiency and infection in rats

Selenium deficiency in rats impairs the ability of neutrophils and peritoneal macrophages to kill Candida albicans organisms in vitro. In contrast, killing of Salmonella typhimurium and Staphylococcus aureus organisms is unaffected by the deficiency. Survival of rats after intraperitoneal injection of 8 X 10(7) S. aureus organisms was not affected by Se deficiency, but a 5-fold increase in the dose (4 X 10(8) S. aureus organisms) led to a significantly greater mortality in the Se deficient rats.     

Visualization and characterization of 5-HT receptors and transporters in vivo and in man

Ascending and descending efferent pathways from the nuclei of serotonergic neurones located in brainstem raphe nuclei project to all regions of the central nervous system. Therefore, in considering the major physiological roles played by this neurotransmitter system, it is not surprising that serotonin is implicated in the aetiologies of many CNS dysfunctions which underlie psychiatric and neurological disorders. The presynaptic serotonin uptake mechanism and the many receptor subtypes that mediate the neurotransmitter roles of serotonin have been, and continue to be, targeted by drug discovery programmes aimed at identifying improved therapies for CNS disorders. Here we review the radioligands available for the important task of visualizing and characterizing these targets in the living human brain using either positron emission tomography (PET) or single photon emission tomography (SPECT). Such studies are crucial for extending our knowledge of the involvement of serotonin neurotransmission in the aetiologies of these disorders and for the development of new and more effective therapies. Particularly important recent advances in the methodologies for imaging the 5-HT transporter, the 5-HT_2A receptor and the 5-HT_1A receptor will almost certainly lead to important clinical research into the changes occurring in serotonergic neurotransmission during the onset, progression and treatment of affective and neurodegenerative disorders.     

ALA和HMME水凝胶栓剂的制备和体内外释药研究

目的 制备光敏剂5-氨基酮戊酸(ALA)和血卟啉单甲醚(HMME)水凝胶栓剂,评价其对直肠肿瘤组织的光敏剂递送效率.方法 将皮下移植人直肠癌细胞SW837的BALB/c小鼠随机分为水凝胶栓剂直肠局部给药组、皮肤局部给药组、瘤内注射给药组和静脉注射给药组.用荧光光谱仪测量直肠壁、皮肤和皮下肿瘤中原卟啉(PpⅨ)和HMME的浓度,荧光光谱系统测定相应的光敏剂分布情况.结果 ALA水凝胶栓剂直肠局部给药组的PpⅨ浓度分别是皮肤局部给药组的9.76倍(1 h)和5.80倍(3 h),差异均具有统计学意义(均P＜0.05).皮肤局部给药后2h,ALA在肿瘤组织内达到最大穿透深度(3～6 mm).而HMME水凝胶栓剂直肠局部给药后,直肠壁中的HMME浓度极低,且皮肤局部给药后的最大肿瘤穿透深度不足2 mm.结论 与皮肤相比,ALA更易穿透黏膜屏障,以水凝胶栓剂形式直肠局部给药有望成为ALA用于光动力疗法治疗直肠癌的一种给药方式.     

高校组织学与胚胎学课程思政研究状况

<正>为了解我国高校组织学与胚胎学课程思政的开展情况。通过检索中国科学引文数据库、维普信息资源系统和万方数据库获得相关文献,从课程思政的基本概念和意义、组织学与胚胎学课程思政状况和展望3个方面进行了归纳。课程思政的提出,目的是为高校思想政治教育改革探索新模式。目前组织学与胚胎学课程思政工作主要从课程思政的目标、思政元素、方法、存在的问题和解决方法等方面开展了探索和研究。     

Characteristics of Tremor in Normal Subjects and in the Diagnosis and Treatment of Parkinsonism

Tensotremorography was used to record voluntary forces and to study the characteristics of the involuntary and voluntary components of isometrically recorded hand strength. The frequency ranges for changes in the spectral density of oscillations recorded here supported the existence of two suprasegmental systems associated with voluntary control and continuous regulation of force maintaining or holding a posture. Cross-correlation analysis of hand force maintained in conditions of visual feedback in normal conditions and in conditions of central disorders of the movement control system is presented.     

Evaluation of the genotoxic and embryotoxic potential of chlorpyrifos and its metabolites in vivo and in vitro

The genotoxicity and embryotoxicity of chlorpyrifos (CPF) and two metabolites were evaluated using the chick embryo, Chinese hamster ovary cells, and by examining blastocysts from superovulated cows crossed to chlorpyrifos-treated bulls. Chlorpyrifos and metabolites were dissolved in acetone and administered to 3-day embryos by the air cell method. The LD50 was 1,500 micrograms/embryo when mortality was checked through and including 17 days of development. The metabolites were more embryotoxic than the parent compound, CPF. Chlorpyrifos and metabolites did not increase the sister chromatid exchange (SCE) frequency above background at any dosage in the 3-day chick embryo assay. Similarly, none of these compounds increased SCE frequencies in three-point dosage tests (1, 10, 100 micrograms/ml) using Chinese hamster ovary cells. Controls in these assays consisted of the solvent carrier acetone (7.0 +/- 2.5 SCE/cell) and 8.6 micrograms/ml methyl methane sulfonate (30.5 +/- 7.4 SCE/cell). Studies of bovine blastocysts obtained from superovulated cows crossed with Dursban 44 treated bulls did not reveal evidence of chromosome aberrations or developmental anomalies associated with pesticide application. However, reproductive performance of breeders may be subnormal as a result of severe poisoning. This underscores the limitations of short-term assays and emphasizes the need to perform thorough toxicological assays of a chemical according to actual usage patterns in the species of concern.     

In vitro and in vivo analyses of constitutive and in vivo-induced promoters in attenuated vaccine and vector strains of Vibrio cholerae

The optimal promoter for in vivo expression of heterologous antigens by live, attenuated vaccine vector strains of Vibrio cholerae is unclear; in vitro analyses of promoter activity may not accurately predict expression of antigens in vivo. We therefore introduced plasmids expressing the B subunit of cholera toxin (CtxB) under the control of a number of promoters into V. cholerae vaccine strain Peru2. We evaluated the tac promoter, which is constitutively expressed in V. cholerae, as well as the in vivo-induced V. cholerae heat shock htpG promoter and the in vivo-induced V. cholerae iron-regulated irgA promoter. The functionality of all promoters was confirmed in vitro. In vitro antigenic expression was highest in vaccine strains expressing CtxB under the control of the tac promoter (2 to 5 microgram/ml/unit of optical density at 600 nm [OD(600)]) and, under low-iron conditions, in strains containing the irgA promoter (5 microgram/ml/OD(600)). We orally inoculated mice with the various vaccine strains and used anti-CtxB immune responses as a marker for in vivo expression of CtxB. The vaccine strain expressing CtxB under the control of the tac promoter elicited the most prominent specific anti-CtxB responses in vivo (serum immunoglobulin G [IgG], P 相似文献   

Cyclic and characteristic expression of phosphorylated Akt in human endometrium and decidual cells in vivo and in vitro

BACKGROUND: Akt is activated by phosphorylation and plays an important role in cell survival and maintenance of structure. METHODS: We investigated whether phosphorylated Akt was characteristically expressed in human endometrium in vivo and whether insulin-like growth factor-I (IGF-I) can activate Akt using cultured decidualized human stromal cells in vitro, using immunohistochemistry and Western blotting analysis. RESULTS: The levels of phosphorylated Akt protein increased markedly in the decidual tissues from ectopic pregnancy. The expression of phosphorylated Akt protein in stromal cells increased with the decidualization. The decidual cells showed strong cytoplasmic staining for phosphorylated Akt. However, cultured decidualized human stromal cells diminished phosphorylated Akt expression compared to control cells. IGF-I administration to decidualized human stromal cells significantly recovered pAkt expression. The effect of IGF-I on decidualized human stromal cells was blocked by an inhibitor of phosphatidylinositol-3 kinase (PI3K) (LY294,002). These results suggest that IGF-I may activate Akt via PI3K in human endometrium and decidua. The expression of phosphorylated Akt in stromal cells was only detected in the functional layer, where tissue remodelling occurs during menstruation or implantation. CONCLUSIONS: Akt activation may be involved in cell survival and extracellular matrix remodelling in human endometrium and decidua.     

Comparison of phage-mediated and conjugative transfer of staphylococcal plasmids in vitro and in vivo

A strain of Staphylococcus aureus was constructed with which to compare transfer of resistance plasmids by the mechanisms of phage-mediated conjugation and conjugation. Transfer by each mechanism could be distinguished by the patterns of resistances transferred. Conjugation was favoured on dry absorbent surfaces, e.g., human skin, tissue and surgical gauze, whereas phage-mediated conjugation was favoured in fluids, e.g., milk and urine. The degree of hydration of the mating cells is postulated as one factor determining whether plasmids are transferred by phage-mediated conjugation or conjugation. Preliminary evidence indicates that topical creams and ointments affect the conjugative transfer of plasmids.