Demonstration of laminin, a basement membrane glycoprotein, in routinely processed formalin-fixed human tissues

Laminin was demonstrated by immunoperoxidase and immunofluorescence staining in sections of normal human tissues fixed in formalin and routinely processed in paraffin. Exposure of the sections to a solution of pepsin (Burns et al. (1980) Histochemistry 67:73-78) revealed the antigenicity of this basement membrane glycoprotein. Sections from paraffin blocks stored for years at room temperature could be stained with this procedure. Normal human tissues, developing fetal tissues and tumors could be stained with this method. The staining patterns were similar to those seen in unfixed frozen sections. It thus appears that basement membrane components can be detected by immunohistological means from routinely processed histological samples, once the sections are pretreated with proteases. Staining for laminin could be used in embryonic studies and in histopathology to study the relation of cells to basement membranes and for the visualization of normal and abnormal vascularization.     

Glomus tumor cells: evaluation of smooth muscle and endothelial cell properties

Six cases of glomus tumor in superficial soft tissues were investigated immunohistochemically for the presence of different types of intermediate filaments, myosin, laminin, a basal lamina glycoprotein, and the endothelial cell markers, factor VIII-related antigen (FVIIIR:Ag) and Ulex europaeus I lectin (UEA I) binding sites. The tumor cells appeared to contain only vimentin, the fibroblast-type of intermediate filament protein. They were also positive for myosin, and were invested by laminin-positive basal lamina-like material, but did not express endothelial cell markers. Ultrastructural studies revealed prominent arrays of both intermediate filaments and microfilaments, the latter resembling the myofilament bundles seen in smooth muscle cells. The results show that glomus tumor cells resemble smooth muscle cells in their content of myosin and in some ultrastructural features. In their lack of desmin, however, they differ from most types of smooth muscle cell, although they are similar in this respect to some vascular smooth muscle cells.     

Nasopharyngeal lymphoepithelioma. Histological diagnosis as aided by immunohistochemical demonstration of keratin

Eight cases of primary and metastatic nasopharyngeal lymphoepithelioma and four cases of malignant lymphoma of the pharyngeal region were studied for the presence of keratin by indirect immunofluorescence microscopy. The results showed that all the cases of primary and metastatic lymphoepithelioma contained keratin-positive cells, whereas all the lymphomas were negative for keratin. Anti-keratin antibody thus seems to be a valuable aid in the differential diagnosis between lymphoepithelioma and lymphoma.     

A review of clinical trials in dietary interventions to decrease the incidence of coronary artery disease

Of the associations between dietary elements and coronary artery disease (CAD), the greatest body of evidence deals with the beneficial effect of reducing the dietary intake of saturated fatty acids and cholesterol. Furthermore, it is well established, on the basis of convincing evidence, that reduction in serum total cholesterol results in reduction in coronary morbidity and mortality, as well as in regression of other atherosclerotic manifestations.In fact, dietary intervention studies revealed that it is possible to reduce the incidence of coronary death and nonfatal myocardial infarction, as well as manifestations of atherosclerosis in cerebral and peripheral arteries, by reducing dietary intake of saturated fat and cholesterol. In two recently reported dietary interventions the incidence of coronary events, especially coronary mortality, and total mortality were reduced by increased intake of n-3 long-chain polyunsaturated fatty acids and by a modification of the diet toward a Mediterranean-type diet (rich in α-linolenic acid. In addition to those findings, the potential efficacy of the dietary newcomers phytostanol and phytosterol esters on reducing coronary incidence is discussed in the present review.     

Do Egg Carrying and Protracted Copulation Affect Mobility in the Golden Egg Bug?

Golden egg bug Phyllomorpha laciniata (Heteroptera, Coreidae) females oviposit on male and female conspecifics that carry ova until they hatch. Embryos benefit from being carried because of diminished risks of predation. Female carriers are never the parents of carried eggs, and males are only rarely the fathers of any carried eggs. Eggs develop and hatch without being carried in the laboratory. Egg carriers may be viewed as victims, exploited by females that encumber them with eggs. The intensity of selection favouring resistance to egg carrying should be proportional to the costs of this behaviour. One possible cost could be a reduction in mobility caused by carried eggs. We compare movement rates among encumbered and unencumbered golden egg bugs of both sexes. Protracted copulations (often exceeding 20 h) typical of this species and mating may also cause reduction in bugs mobility. Therefore, we also evaluate rates of movement of coupled pairs of bugs. Our results indicate that egg loads do not affect the mobility and speed of either males or females. However, copulating pairs are significantly slowed as compared to single bugs. Thus protracted copulations have a clear cost in rates of movement and possibly risks of predation, but there are no apparent mobility costs for egg carrying.     

Effect of Feeding on Reproductive Performance in Finnish Dairy Cows

The effect of 2 types of feeding on the involution of the genital tract and on the fertility was studied in 79 Finnish dairy cows on a research farm. The cows were fed twice a day with home-produced feed in accordance with the Finnish feeding standard. The cows were divided according to the type of feed into a hay-urea group and a silage group. The cows were examined clinically by rectal palpation 3 times a week during 8 weeks postpartum. The time required for the complete involution of uterus and cervix was recorded. The cows in the silage group had a significantly longer time in uterine involution, a lower fertility rate at first insemination and a longer interval from calving to conception than those in the hay-urea group. The pregnancy rate in the first insemination was in the hay-urea group 91 % and in the silage group 57 %. The interval between calving and the first insemination was shorter in the hay-urea group than in the silage group; 71.4 ± 10.6 and 74.0 ± 10.3 days, respectively. The interval between calving and conception was in the hay-urea group significantly (p < 0.01) shorter than in the silage group; 74.8 ± 15.1 and 89.5 ± 24.4 days, respectively.