Metastasis of mammary carcinomas in GRS/A hybrid mice transgenic for the mts1 gene

Transgenic mice, carrying the mts1 gene, one of the genes involved in the acquisition of the metastatic phenotype, were generated. The mts1 gene was placed under the control of the mouse mammary tumor virus (MMTV) long terminal repeat (LTR) promoter leading to overexpression in the lactating mammary gland of transgenic animals. Animals bearing the transgene appear phenotypically normal. Animals of two transgenic lines (Tg463 and Tg507) were crossed with the GRS/A mice. The GRS/A strain is characterized by high incidence of mammary tumors which rarely metastasize. 40% of the tumor bearing hybrid GRS/A mts1 females were found to develop secondary tumors in the lungs. The Mts1 protein was detected in the transgene primary tumor cells as well as in the corresponding metastases. Nontransgenic littermates expressed the Mts1 protein only in the stromal cells surrounding the tumor but not in the tumor cells by itself. Taken together these observations indicate that overexpression of the mts1 gene in the mouse mammary carcinoma cells gives rise to more aggressive tumors which are able to metastasize.     

Differential expression of TGF-beta 1, 2 and 3 isotypes in Alzheimer''s disease: a comparative immunohistochemical study with cerebral infarction, aged human and mouse control brains

The Chinese version of the Dyadic Adjustment Scale (C-DAS) was administered to 1,501 married adults, along with other instruments that assessed their psychosocial adjustment. Factor analysis showed that four factors were abstracted from the C-DAS (Dyadic Consensus, Dyadic Cohesion, Dyadic Satisfaction, and Affectional Expression); the factors extracted could be reproduced reliably in two random subsamples, as well as in the male and female samples. Although some areas of refinement are suggested, the present data generally support the universality of the concept of dyadic adjustment as indexed by the Dyadic Adjustment Scale. Contrary to the data reported previously, the present factor structures based on the male and female samples were highly similar and stable.     

Tunable infrared generation using a femtosecond 250 kHz Ti:sapphireregenerative amplifier

A mode-locked Ti:sapphire regenerative amplifier system pumped with a single argon ion laser produces μJ energy 100 femtosecond pulses of 800 nm wavelength at 250 kHz repetition rate. Pumping a Type II BaB₂O₄ (BBO) optical parametric amplifiers (OPA) with this output generates 500 nJ infrared pulses and continuous tuning from 1.1 μm to beyond 2.5 μm. Difference frequency generation of the signal idler output from this OPA source in AgGaS₂ produces 60 nJ mid infrared pulses and continuous tuning from 2.4 μm to beyond 12 μm     

Memory for the content of caches by scrub jays (Aphelocoma coerulescens)

In Alzheimer's disease (AD) there is neuronal loss in the locus ceruleus (LC), and the noradrenergic system may be even more affected in depressed AD patients. However, this neuronal loss may go together with an increase in activity of the remaining noradrenergic neurons. We prospectively evaluated 16 AD patients (6 depressed, 5 transiently depressed, and 5 nondepressed) and 10 controls. We determined norepinephrine and its metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) in various brain areas, and compared these data with previously established neuron numbers in the LC in the same patients. We could not confirm earlier studies reporting lower norepinephrine concentrations in depressed than in nondepressed dementia patients. The mean norepinephrine concentrations in AD patients were significantly lower than those in control patients, whereas the mean concentrations of MHPG were not different. Moreover, we found significant inverse relationships between the number of remaining pigmented LC neurons and the MHPG/norepinephrine ratio in the frontal cortex and LC. These data are the first to provide direct evidence for the hypothesis that remaining LC neurons are activated to compensate for decreased cerebral norepinephrine levels in AD, by demonstrating that the MHPG/norepinephrine ratio is significantly higher in AD, indicating increased metabolism.     

Groundwater recovery problems associated with opencast mine backfills in the United Kingdom

The paper presents the main findings of the research work conducted over the past three years into the environmental effects associated with surface mining. Especial considerations have been give to the re-establishment of the natural groundwater regime, as a consequence of opencast site restoration. A summary of the results of the research is presented and two specific topics, namely, the stability of backfilled masses and the pollution of groundwater are detailed. The project was based on field and laboratory investigations, and details of this work along with some general conclusions are given.     

Flexed plate impact testing of poly(ether sulphone)

Injection-moulded discs of poly(ether sulphone) impacted at 5 m sec^–1 in a standard flexed-plate configuration fail by a ductile penetration process and the peak force is proportional to the specimen thickness. The peak force is reduced, and the specimen is often embrittled, if there is a machined stress concentrator at the point of impact. The simplest stress concentrator, a hole bored through the specimen, reduces the peak force by about one-third and reduces the overall ductility, even to the point of brittleness in some cases, but it does not constitute a severe notch. The results can all be rationalized in terms of the ratio of peak force to thickness.