Sibling visitation--a plan for change

The philosophy of family centered care in a newborn intensive care unit encourages not only parent participation but involvement of the well sibling in the family process. This article describes how a group of staff nurses fostered the emotional well-being of the ill neonates's sibling by changing the status of sibling visitation in their unit.     

Coordination polymerization of lactides, 1. Structure determination of obtained polymers

Racemic lactide was polymerized with various initiators containing Zn and Al, and the structures of the obtained polymers were determined by means of ¹³C NMR spectroscopy. The extent of transesterification reactions was calculated on the basis of the analysis of the methine carbon signal in the polymer ¹³C NMR spectra. Three groups of initiators can be distinguished in view of their influence on transesterification: ZnCl₂ exhibits the strongest transesterification activity, ZnEt₂ and ZnEt₂/Al(OiPr)₃ are among those of medium activity, and Al(acac)₃ does not show transesterification activity at all.     

Metastatic potential of human CX-1 colon adenocarcinoma cells is dependent on the expression of sialosyl Le a antigen

Several lines of evidence indicate that sialosyl Le a , tumor-associated carbohydrate antigen present on human colon carcinoma cells, is involved in formation of metastases. To study the role of this carbohydrate structure in development of metastases, we have used the clone of human colon carcinoma CX-1 cells transfected with antisense expression vector containing fragment of cDNA for a1,3/4-fucosyltransferase (FT III), which is involved in synthesis of sialosyl Le a tetrasaccharide. It has been reported previously that, in contrast to the parental cells, the antisense-transfected CX-1.1AS5 cells do not express sialosyl Le a and do not adhere to E-selectin-expressing CHO cells. In the present work we have studied the formation of liver metastases by CX-1.1AS5 cells after their orthotopic or intrasplenic implantation into athymic nu/nu mice. After orthotopic implantation of sialosyl Le a -negative colon carcinoma CX-1.1AS5 cells, the number of mice with liver metas-tases was markedly lower (21% of mice) in comparison with their number after implantation of the parental CX-1.1 cells (86% of mice). However, no differences in ability to form colonies in liver were observed between parental CX-1.1 cells and antisense-transfected CX-1.1AS5 cells after intrasplenic inoculation. The liver metastases were formed in 89% and 84% of mice, respectively. Our data support the thesis on the importance of sialosyl Le a antigen expression in the development of liver metastases by colon cancer cells, and indicate the role of transplantation route and primary tumor localization in formation of metastases.© Kluwer Academic Publishers 1998     

TGFbeta1 enhances formation of cellular Abeta/apoE deposits in vascular myocytes

Brain injury increases the risk of Alzheimer's disease (AD) through unknown mechanisms. We studied deposition of amyloid-beta protein (Abeta) in cells exposed to transforming growth factor beta1 (TGFbeta1), a cytokine that regulates cell metabolism during brain injury, and apolipoproteinE (apoE), the major lipid transporter in the brain. The studies were conducted by using brain vascular smooth muscle cells that are engaged in beta-amyloidosis in vivo and produce Abeta in cell culture. We found that cell treatment with TGFbeta1 together with apoE4 strongly increased the amount of cellular Abeta. The intracellular Abeta co-localized with apoE but not with TGFbeta, similarly as in vascular beta-amyloid. Some cellular Abeta/apoE deposits increased in size and persisted in culture even after the TGFbeta1 and apoE4 were removed. The appearance of cellular deposits of Abeta was associated with increased production of the amyloid-beta precursor protein and cellular retention of its mature form. The results suggest that the concomitant presence of apoE and TGFbeta1 can trigger vascular beta-amyloidosis by inducing intracellular formation of stable Abeta/apoE deposits.     

Acoustic startle response in the opossum Monodelphis domestica in comparison with the Wistar albino rat

The acoustic startle response (ASR) was studied in 20 gray short-tailed opossums (Monodelphis domestica) and its characteristics were compared with those obtained from responses of 20 Wistar albino rats. The animals were exposed to 10 ms, 110 dB white noise acoustic pulses in the Coulbourn apparatus. Amplitude of ASR was normalized to the weight of animals and then analyzed. The results show that probability of a freezing response is much higher in the opossums that generally respond with lower startle amplitudes in comparison to rats. These differences may reflect different emotional characteristics of the two species, different reactions to fear in opossum and/or different ecological specializations of the two species.     

Proliferative response of T lymphocytes to a proline-rich polypeptide (PRP): PRP mimics mitogenic activity of Il-1

Mitogenic properties of a proline-rich polypeptide were investigated. The mitogenic action of PRP was compared with the mitogenic action of Il-1. PRP was not mitogenic for thymocytes at doses 0.01-50 micrograms/ml. PRP, at doses 0.1-50 micrograms/ml, augmented the proliferative response of thymocytes to Con A in a similar fashion as Il-1. At doses higher than 10 micrograms/ml, PRP induced proliferation of lymph node cells and splenocytes as well as T cells from the lymph nodes. It did not, however, cause significant proliferation of B cells from the lymph nodes, at the doses used. PRP did not induce proliferation of an antigen specific Lyt 1+ T cell clone. Il-1 behaved in a similar way as PRP in all the tests described. We consider a possibility that under physiological conditions, at a very early stage of postneonatal life, PRP may replace some functions of Il-1.     

Chromosome changes associated with spontaneous phenotypic variation of transplantable melanoma

The chromosome constitutions of black-melanotic (Ma), brown-melanotic (MI), and amelanotic (Ab) melanomas of the Syrian hamster were compared. The MI and Ab melanomas arose through a spontaneous phenotypic alteration of the Ma tumor. All three variants differ in their growth rates, with MI showing the slowest, Ab the fastest, and Ma intermediate growth rate. Cytogenetic examination revealed that each tumor line shows a distinct karyotype. The Ma tumor is near-diploid, whereas, Ab and MI tumors are hypertriploid and near-tetraploid, respectively. Each tumor line shows a unique set of marker chromosomes, though some markers are shared by two different tumor lines. No single marker chromosome was common for all three melanoma variants. We conclude that the spontaneous phenotypic variation of transplantable hamster melanomas is associated with profound changes in the chromosome constitution of the neoplastic cells. The general direction of these changes is toward increased ploidy and increased complexity of the structural abnormalities.     

Krukenberg tumor--8 years after surgical treatment of gastric carcinoma

The aim of the study was to discuss the case of Krukenberg tumor in a patient, eight years after the diagnosis and surgical treatment of gastric carcinoma. We have concluded that there was no safe period after which distant metastases may be excluded. In case of gastric carcinoma diagnosed in women, a regular gynecological examination is necessary due to a high propability of metastases into ovaries, even if the clinical stage of gastric carcinoma is low.