Ultrasound of the whole breast utilizing a dedicated automated breast scanner

Innovations in design of a dedicated breast scanner resulted in automation of the scanning process, the production of high resolution images of the whole breast and an efficient mode of image review. The results of clinical evaluation of the prototype of this breast scanner investigating normal breasts as well as benign and malignant breast lesions are presented.     

Developmental toxicity study with triethylene glycol given by gavage to CD rats and CD-1 mice

Triethylene glycol (TEG) is a liquid industrial chemical with a potential for human exposure. The likelihood for developmental toxicity was investigated in two species. Timed-pregnant CD rats and CD-1 mice were dosed daily by gavage with undiluted TEG over gestational days (gd) 5-15 at 0.0 (water control), 1126, 5630 or 11,260 mg kg(-1) day(-1) with rats and 0.0, 563, 5630 or 11,260 mg kg(-1) day(-1) with mice. They were examined daily, and gestational body weights and food and water consumption measured throughout gestation. At necropsy on gd 21 (rats) or gd 18 (mice) dams were examined for body, gravid uterine, liver and kidney weights, and implantation sites. Maternal kidneys were examined histologically. Fetuses were weighed, sex determined, and examined for external, soft tissue and skeletal variations and malformations. Rat dams had reduced body weights, body weight gains, and food consumption, and increased water consumption and relative kidney weights at 11,260 mg kg(-1) day(-1). They also had reduced body weight and increased water consumption at 5630 mg kg(-1) day(-1). Mice had clinical signs and increased relative kidney weight at 11,260 mg kg(-1) day(-1). Renal histology was normal in both species. Neither species had treatment-related effects on corpora lutea or implantations. Fetal body weights were reduced at 11,260 mg kg(-1) day(-1) (both species) and 5630 mg kg(-1) day(-1) (mice). In rat fetuses there was a pattern of delayed ossification in the thoracic region at 11,260 mg kg(-1) day(-1). Mouse fetuses had delayed ossification in the frontal and supraoccipital bones, cervical region, hindlimb proximal phalanges and reduced caudal segments at 11,260 mg kg(-1) day(-1), and in the skull bones at 5630 mg kg(-1) day(-1). These patterns of delayed ossification are consistent with reduced fetal body weights. No biologically significant embryotoxicity or teratogenicity was observed at any dosage in either species. The NOEL for TEG given by gavage over the period of organogenesis was 1126 mg kg(-1) day(-1) in the rat and 5630 mg kg(-1) day(-1) in the mouse for maternal toxicity, and 5630 mg kg(-1) day(-1) (rat) and 563 mg kg(-1) day(-1) (mouse) for developmental toxicology.     

Triethylene glycol HO(CH2CH2O)3H

TEG is a liquid higher glycol of very low vapor pressure with uses that are primarily industrial. It has a very low order of acute toxicity by i.v., i.p., peroral, percutaneous and inhalation (vapor and aerosol) routes of exposure. It does not produce primary skin irritation. Acute eye contact with the liquid causes mild local transient irritation (conjunctival hyperemia and slight chemosis) but does not induce corneal injury. Animal maximization and human volunteer repeated insult patch tests studies have shown that TEG does not cause skin sensitization. A study with Swiss-Webster mice demonstrated that TEG aerosol has properties of a peripheral chemosensory irritant material and caused a depression of breathing rate with an RD(50) of 5140 mg m(-3). Continuous subchronic peroral dosing of TEG in the diet of rats did not produce any systemic cumulative or long-term toxicity. The effects seen were dose-related increased relative kidney weight, increased urine volume and decreased urine pH, probably a result of the renal excretion of TEG and metabolites following the absorption of large doses of TEG. There was also decreased hemoglobin concentration, decreased hematocrit and increased mean corpuscular volume, probably due to hemodilution following absorption of TEG. The NOAEL was 20 000 ppm TEG in diet. Short-term repeated aerosol exposure studies in the rat demonstrated that, by nose-only exposure, the threshold for effects by respiratory tract exposure was 1036 mg m(-3). Neither high dosage acute nor repeated exposures to TEG produce hepatorenal injury characteristic of that caused by the lower glycol homologues. Elimination studies with acute peroral doses of TEG given to rats and rabbits showed high recoveries (91-98% over 5 days), with the major fraction appearing in urine (84-94%) and only 1% as CO(2). TEG in urine is present in unchanged and oxidized forms, but only negligible amounts as oxalic acid. Developmental toxicity studies with undiluted TEG given by gavage produced maternal toxicity in rats (body weight, food consumption, water consumption, and relative kidney weight) with a NOEL of 1126 mg kg(-1) day(-1), and mice (relative kidney weight) with a NOEL of 5630 mg kg(-1) day(-1). Developmental toxicity, expressed as fetotoxicity, had a NOEL of 5630 mg kg(-1) day(-1) with the rat and 563 mg kg(-1) day(-1) with mice. Neither species showed any evidence of embryotoxicity or teratogenicity. There was no evidence for reproductive toxicity with mice given up to 3% TEG in drinking water in a continuous breeding study. TEG did not produce mutagenic or clastogenic effects in the following in vitro genetic toxicology studies: Salmonella typhimurium reverse mutation test, SOS-chromotest in E. coli, CHO forward gene mutation test (HGPRT locus), CHO sister chromatid exchange test, and a chromosome aberration test with CHO cells. The use patterns suggest that exposure to TEG is mainly occupational, with limited exposures by consumers. Exposure is normally by skin and eye contact. Local and systemic adverse health effects by cutaneous exposure are likely not to occur, and eye contact will produce transient irritation without corneal injury. The very low vapor pressure of TEG makes it unlikely that significant vapor exposure will occur. Aerosol exposure is not a usual exposure mode, and acute aerosol exposures are unlikely to be harmful, although a peripheral sensory irritant effect may develop. However, repeated exposures to a TEG aerosol may result in respiratory tract irritation, with cough, shortness of breath and tightness of the chest. Recommended protective and precautionary measures include protective gloves, goggles or safety glasses and mechanical room ventilation. LC(50) data to various fish, aquatic invertebrates and algae, indicate that TEG is essentially nontoxic to aquatic organisms. Also, sustained exposure studies have demonstrated that TEG is of a low order of chronic aquatic toxicity. The bioconcentration potential, environmental hydrolysis, and photolysis rates are low, and soil mobility high. In the atmosphere TEG is degraded by reacting with photochemically produced hydroxyl radicals. These considerations indicate that the potential for ecotoxicological effects with TEG is low.     

Social Play Behavior in Adolescent Rats is Mediated by Functional Activity in Medial Prefrontal Cortex and Striatum

Social play behavior is a characteristic, vigorous form of social interaction in young mammals. It is highly rewarding and thought to be of major importance for social and cognitive development. The neural substrates of social play are incompletely understood, but there is evidence to support a role for the prefrontal cortex (PFC) and striatum in this behavior. Using pharmacological inactivation methods, ie, infusions of GABA receptor agonists (baclofen and muscimol; B&M) or the AMPA/kainate receptor antagonist 6,7-dinitroquinoxaline-2,3(1H,4H)-dione (DNQX), we investigated the involvement of several subregions of the medial PFC and striatum in social play. Inactivation of the prelimbic cortex, infralimbic cortex, and medial/ventral orbitofrontal cortex using B&M markedly reduced frequency and duration of social play behavior. Local administration of DNQX into the dorsomedial striatum increased the frequency and duration of social play, whereas infusion of B&M tended to have the same effect. Inactivation of the nucleus accumbens (NAcc) core using B&M increased duration but not frequency of social play, whereas B&M infusion into the NAcc shell did not influence social play behavior. Thus, functional integrity of the medial PFC is important for the expression of social play behavior. Glutamatergic inputs into the dorsomedial striatum exert an inhibitory influence on social play, and functional activity in the NAcc core acts to limit the length of playful interactions. These results highlight the importance of prefrontal and striatal circuits implicated in cognitive control, decision making, behavioral inhibition, and reward-associated processes in social play behavior.     

保元强肾Ⅱ号胶囊对慢性肾功能衰竭肾小管间质损伤的临床研究

目的:探讨中药保元强肾Ⅱ号胶囊对慢性肾功能衰竭(CRF)的疗效及机理。方法:60例CRF患者随机分为保元强肾Ⅱ号胶囊加洛汀新组(治疗组,30例)及必需氨基酸加洛汀新组(对照组,30例),观察肾功能及肾小管标志蛋白的改变。结果:治疗组显效率及总有效率分别为633%及933%;对照组分别为300%及567%,治疗组疗效明显优于对照组(P<001);治疗组治疗后BUN、SCr及CCr均较治前明显改善,尿视黄醇结合蛋白、尿β2微球蛋白及尿N乙酰氨基葡萄糖苷酶均比治疗前显著降低,TammHorfau蛋白比治疗前显著增高(P<001或P<005)。结论:保元强肾Ⅱ号胶囊对肾小管间质损伤有明显的改善作用,从而改善肾功能,提高疗效。