The spermatozoal volume as indicative of the plasma membrane integrity (modification of the hypoosmotic swelling test). I. Methods

Summary. The aim of the present study was to establish a more differentiating indicator of plasma membrane integrity of spermatozoa than the classic version of the hypoosmotic swelling test according to Jeyendraan. Spermatozoa were prepared by density gradient centrifugation (90% Percoll) to select 'fertilization competent' spermatozoa only. After a second washing procedure sufficiently pure sperm cell suspensions were obtained. The volume distributions of these sperm cells were measured with a Coulter Counter at 25 °C after adaptation in 300 mosmolar NaCl solution resp. 150 mosmolar NaCl solution for 5 min. These volume distributions showed significantly different patterns for the isotonic and hypotonic stress situation in the simple salt solution. Moreover, the comparison of the response to hypoosmotic stress showed more than four reproducible characteristic patterns, promising well differentiated results for different sperm populations. The new method for the detection of hypoosmotic swelling effect might be a real and valuable functional parameter.     

Effect of “Re Du Qing” on the activation,proliferation and membrane fluidity of lymphocytes

Summary Effects of Chinese Medicinal Preparation “Re Du Qing” (RDQ) on the activation, proliferation and membrane fluidity of T lymphocytes from human peripheral blood Were studied by means of³H-TdR incorporation and DPH fluorescence polarization. The results showed that “RDQ” can:1) significantly inhibit the activation of T lymphocytes; 2) restrain the proliferation of activated T lymphoblasts in the presence of exogenous interleukin-2 (IL-2); and 3) increase the membrane fluidity of T lymphocytes and antagonize the decreased fluidity of lymphocyte membrane mediated by Con A or PHA. The functional abnormalities of T lymphocytes in some autoimmune diseases such as arthritis and the usefulness of RDQ in the treatment of these diseases were also discussed.     

Familial Juvenile Nephronophthisis in Two Siblings — Histological Findings at an Early Stage —

We present two female siblings with familial juvenile nephronophthisis (FJN) which was diagnosed at the early stage of renal failure. Diagnosis was made during the investigation of anemia in case 1 and by a subsequent family survey in case 2. Most patients with FJN are not identified until the terminal stage of renal failure and such cases have rarely been reported in Japan. Case 2 had a reduction in the maximum urinary concentration ability but no azotemia, and among the FJN patients reported in Japan so far she has the least advanced renal disease. Histological examination of the renal biopsy in case 1 showed typical findings of FJN, such as thickening and lamination of the tubular basement membrane (TBM), interstitial fibrosis, and round cell infiltration of the interstitium. In case 2, renal biopsy revealed an irregular marked thickening of the TBM with trivial interstitial changes and a normal glomerular appearance. The histology of these two cases suggests that the TBM may be the primary site affected in FJN.     

Efficient RT-PCR on platelet mRNA after long-term storage

We have developed a procedure permitting RT-PCR from mRNA even after a long-term storage (1 year) of platelet samples in ethanol (EtOH-platelets) at −80°C. To validate our method, we have analysed the human platelet alloantigen system (HPA-1) which is coded by β₃ mRNA. We have also demonstrated the efficiency of amplification of part of the coding region for (i) α_IIb subunit mRNA, (ii) α_v subunit mRNA, and (iii) the seven transmembrane domain thrombin receptor mRNA.     

Protection of melatonin against damage of sperm mito-chondrial function induced by reactive oxygen species

Aim: To study the mitochondrial function damage of sperm in-duced by reactive oxygen species (ROS) and the protection of melatonin (MLT) against the damage. Methods: Normal function spermatozoa were selected from semen samples by Percoll gradi-ent centrifugation technique. The ROS generated by the hypoxan-thine xanthine oxidase system was incubated with the normal sper-matozoa in the presence or absence of MLT (6 retool/L) for 30 and 60 minutes.     

Comparative observation of protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure

Objective: To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure (BUP). Methods : The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses ( ABR). The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells (OHCs) loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. Results: An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa (P<0.01). The rate of perforation of tympanic membrane reached 87.5 % and that of total OHCs loss was 19.46%±5.38% at 14d after exposure. The guinea pigs protected with barrel and earplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection (P<0.01). All of the tympanic membrane and ossicular chain of the protected animals maintained their integrities. Meanwhile, the guinea pigs protected with the barrel had lower ABR threshold and total OHCs loss rate than those with earplug (P<0.01). Conclusions: The earplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug.     

Effect of L(+)-tartrate on some biochemical and enzymatic parameters in normal and glycollate treated rats

Some biochemical and enzymatic constituents were determined in the small intestinal tract tissues of normal and sodium glycollate treated adult male rats. Alterations were observed with respect to certain lipids and carbohydrate fractions in the glycollate fed rats. DNA content was also elevated in this group. The functions of the cell membrane is likely to be affected as reflected in the levels of transport ATPases and orthophospho-hydrolases. The activities of the two marker enzymes in the intestinal brush border, namely alkaline phosphatase and leucylnaphthylamidase were reduced in the glycollate administered group. Administration of L(+)-tartrate, which is a mild laxative and has a regulatory influence on oxalate metabolism, lowered the activities of Na+, K(+)- and Ca(2+)-ATPases. There was a distinct lowering in the level of acid phosphatase in the tartrate treated rats.     

Studies on monoclonal anti-isotypic and anti-idiotypic antibodies against leukemia and myeloma: IV modulation of membrane fluidity of leukemic cell lines and tonsillar cell stimulated with McAbs

Summary In this study the technique of labelling the cell membrane with DPH fluorescence polarization was used to observe the membrane fluidity of B lymphocytic cell lines and tonsillar cells from healthy persons; the modulation effect on membrane-fluidity induced by McAbs against isotypic and idiotypic determinants of IgM from patients with leukemia was studied as well. The expression of the corresponding isotypic and idiotypic determinants of IgM on the cell membrane was determined. The results show that the membrane fluidity of leukemic cell lines is remarkably higher than that of tonsillar cells from healthy persons, and McAbs against isotypic determinants of leukemic IgM can enhance the membrane fluidity of all kinds of cells mentioned above. However, the anti-idiotypic monoclonal antibody increased only the membrane fluidity of leukemic cell lines. These results indicated that there was a close relationship between the effect of McAbs on cell membrane fluidity and the expression of corresponding isotypic and idiotypic determinants of IgM on the cell membrane.