The application of various electron microscopic techniques for ultrastructural characterization of the human papillary heart muscle cell in biopsy material

Summary Various electron microscopical techniques have been applied to biopsy material obtained from patients suffering from mitral stenosis in order to characterize the subcellular organization of the hypertrophied papillary muscle. Small pieces of the same sample were processed for correlative transmission - (TEM) and scanning -(SEM) electron microscopical studies. TEM was carried out on conventionally fixed tissue with or withouten bloc staining with a Cu-Pb citrate solution, and on freeze fracture replicas, while cryofractured material was studied by SEM. Stereo electron micrographs of the Cu-Pb impregnated tissue and of the cryofractured material were especially useful for studying the spatial distribution and relationship between various cell organelles.The myofilaments of the hypertrophied cells were arranged in a normal hexagonal pattern. Regions with irregular orientation of the myofibrils were occasionally seen. Accumulations of interfilamentous glycogen particles adjacent to the Z-bands were characteristic patterns of the contracted muscle cells. The extensive nexuses frequently observed in the subsarcolemmal regions may reflect functional alterations of the intercommunication between hypertrophied cells. The T-tubules were relatively few and irregularly distributed, and the complexity of the sarcotubular system (SR) revealed regional variations. Excellent visualization of the interior couplings between the SR and the T-tubules was achieved by studying thick sections of Cu-Pb impregnated tissue in the TEM.The dense staining of the various intracellular membranes when compared with the almost unstained external membranes including the free cell surface, intercalated disc and T-system, strongly indicates differences in chemical and functional properties of the two membrane systems.En bloc staining resulted also in contrasted glycogen as well as components of the nucleolus and the heterochromatin. The biochemical basis for the selective staining remains obscure; it may be a result of binding of heavy metal ions to carboxyl groups of specific proteins, and/or it may represent deposits of lead phosphate.     

Studies on the infectivity of Fasciola hepatica miracidia to Lymnaea truncatula. Attachment and penetration of miracidia into non-infected and infected snails

Summary Fasciola hepatica miracidia labelled in vivo with radioselenium have been used in studies on the capacity of the miracidia to attach to and penetrate the tegument of infected compared with non-infected host snails (Lymnaea truncatula). The results show that the penetration of the larvae into the snail tissue is not influenced by an already existing infection, regardless of its developmental stage.     

Cytokine and surface receptor diversity of NK cells in resistant C3H/HeN and susceptible BALB/c mice with chronic Pseudomonas aeruginosa lung infection

The purpose of the present study was to investigate whether NK cells from resistant C3H/HeN mice and susceptible BALB/c mice showed different release of cytokines and expression of surface molecules during chronic P. aeruginosa lung infection using alginate-embedded P. aeruginosa mimicking the infection in cystic fibrosis. Lung cell suspensions were depleted of lymphocytes by magnetic cell sorting. The concentrations of IFN-gamma, IL-1beta and GM-CSF were estimated by ELISA at day 1 and 2 after infection. Non-infected mice were used as controls. Flow cytometry was used to estimate the surface expression of the LFA-1 and Fc receptors on NK cells. At day 2, IFN-gamma levels increased in C3H/HeN mice but decreased in BALB/c mice. The GM-CSF levels increased only in the C3H/HeN mice at day 1 and 2. Surface expression of LFA-1 on the NK cells was higher in C3H/HeN mice at day 1 and 2. In contrast, the expression of Fc receptors was significantly lower on NK cells in C3H/HeN mice at day 1 and 2. In conclusion, the present results show phenotypic differences in NK cells in the two mice strains in chronic P. aeruginosa lung infection, indicating different modulating effects in the Th1/Th2 balance.     

Nucleolar organiser regions in hyperplastic and neoplastic prostatic tissue

Summary Silver-stained nucleolar organiser regions (AgNORs) were studied in 10 hyperplastic, 5 intra-epithelial neoplastic and 30 malignant prostatic lesions. Total AgNOR counts and types were compared with histological features. The total AgNOR count per nucleus was significantly higher (p<0.05) in prostatic intra-epithelial neoplasia (PIN) and adenocarcinoma compared with prostatic hyperplasia. In addition, satellite Ag-NORs predominated in hyperplasia, while medium-sized and large nucleoli with granular AgNORs were only observed in PIN and adenocarcinoma. The results indicate that, despite statistically significant differences, Ag-NOR counts are of no use for diagnosis of any single case in the groups studied, because of considerable overlap. AgNOR typing, however, may contribute to the differential diagnosis between benign and malignant lesions. We propose a new AgNOR typing system.     

Changes in blood cell response following strenuous physical exercise

Summary The generation of tumour necrosis factor (TNF) and tissue factor activity in lipopolysaccharide (LPS) stimulated blood were studied in 25 healthy subjects before and after physical exercise of different intensities. Of the subjects a group of 9 were athletes who trained once to twice every day of the week, a second group of 8 exercised 3–7 times a week, and a third group of 8 exercised 4–5 times a month. The production of TNF in freshly drawn LPS stimulated blood in heparin, drawn from top athletes at rest was significantly lower than in the other subjects. The LPS induced concentrations of TNF- of 2.73 (SEM 1.05) ng · ml^–1 in the blood of the top athletes compared to 5.08 (SEM 0.7) ng · ml^–1 and 7.6 (SEM 1.6) ng · ml^–1, respectively, in the other two groups. The group that trained the least had the highest values. Immediately after exercise, the monocytes appeared to be less responsive to LPS stimulation, as a reduction of 47%–48% was observed in the top athletes and in the other group of well-trained individuals. The group that trained the least, which was also subjected to the least stressful exercise, had a 33% reduction in TNF production. Within 6 h the TNF concentration was back to pre-exercise values. Within 6 h the TNF concentration was back to pre-exercise values. In contrast to TNF production, the LPS induced tissue factor activity of monocytes was significantly higher in the top athletes and in the group of well-trained individuals when measured immediately after 10 min of exercise compared to pre-exercise values. The increase in tissue factor activity was probably a reflection of simultaneous granulocyte- and platelet activation which is known to enhance LPS induced tissue factor activity in monocytes. Except for the period immediately after exercise, there was a significant correlation between LPS induced TNF and tissue factor activity in the whole blood of the participants. In conclusion, hard physical training appeared to suppress the availability of TNF in stimulated blood. This was even more pronounced immediately after strenuous physical exercise.     

Killer cell immunoglobulin-like receptor three domains long cytoplasmic tail 1 gene *007 may modulate disease progression of human immunodeficiency virus-1 infection in the Japanese population

One of the KIR allele, KIR3DL1*007, was associated with the progression to acquired immunodeficiency syndrome and not with the susceptibility to HIV-1 infection in the Japanese and Indian populations, implying that KIR3DL1*007-positive NK cells might eliminate HIV-infected cells less effectively than NK cells bearing the other KIR3DL1 alleles or KIR3DS1 alleles.     

Reaching adulthood with Hirschsprung's disease: Patient experiences and recommendations for transitional care

Background/PurposeThe need for transitional care has gained increased focus in the treatment of patients with congenital colorectal disorders. We aimed to acquire in-depth knowledge about the experiences of adult patients with Hirschsprung's disease (HD) and their suggestions for transitional care.MethodsBinational study applying gender equal focus group interviews (FGI).ResultsSeventeen (9 men) of 52 invited patients with median age 29 (19–43) years participated. Three themes evolved from the FGI. “Scarred body and soul” describes the somatic and psychosocial challenges the patients experienced and “limited health literacy on HD” refers to the patients' lack of HD knowledge. “Absent transition” depicts missing transitional care and the patients' inability to find adult HD specialists. The adult HD patients strongly recommended transitional care from early teens with focus on information about HD and establishment of a peer-to-peer program. They also emphasized the possibility of being referred to a pelvic floor center.ConclusionsHD negatively influences patients' somatic and psychosocial health in childhood, adolescence and adulthood. Adult HD patients strongly recommend transitional care from early teens and the possibility for referral to a center working with pelvic floor dysfunctions.Level of evidenceIVType of researchClinical     

Stereoscan studies of eggs,free-swimming and penetrating miracidia and early sporocysts of Fasciola hepatica

Summary The egg of Fasciola hepatica has a smooth surface with a slightly elevated circle marking the fracture of the operculum. The operculum and the aperture have crenated edges.The epithelial cells of the miracidium are covered with long cilia. When miracidia are vibrated in an ultrasonic cleaner the cilia of the epithelial cells of the four posterior tiers are broken off only leaving longitudinal rows of cilium stubs, whereas the cilia of the first tier are still retained.The apical papilla is provided with a dorso-ventral furrow, multiciliated pits and isolated sensory cilia. The narrow intercellular ridge is smooth, whereas the epithelial cells have small cytoplasmic knobs between the cilia.The penetration into the snail (Lymnaea truncatula) and the transformation into sporocyst may be separated into three phases. (1) Less than 1 min after attachment to the snail the ciliated cells of the anterior tier are shed and swim away. (2) The cilia of the remaining cells beat violently and after about 5 min most cilia are broken off near the cell surface. The miracidium remains for about 15 min embedded as far as the intercellular ridge receptors (lateral papillae and sheathed ciliated nerve endings). During this period extensive contraction and relaxation of the body are performed. (3) The final penetration of the snail epithelium takes about 15 min. Simultaneously with the penetration into the snail tissue the bald cells (epithelial cells with cilium stubs only) of the four posterior tiers loosen, form globules and fall off. The surface below the cells is smooth and in cytoplasmic continuity with the intercellular ridge and the apical papilla, and this syncytium forms the later tegument of the sporocyst. After a few days the tegument of the sporocyst is provided with microvillus-like projections and the apical papilla and sensory structures are lost.Abbreviations AP apical papilla - C cilium or cilium stub - CN ciliated nerve ending - CP ciliated pit - EP Excretory pore - IR intercellular ridge - LP lateral papilla - SC sheathed ciliated nerve ending - 1, 2, 3, 4, and 5 epithelial cell in tier No. 1, 2, 3, 4, and 5 respectively