[Pharmacokinetics of contragestazol (DL-111-IT), a new non-steroid antifertility agent in monkeys]

The pharmacokinetics of contragestazol, an early pregnancy temperating agent [3-(2-ethylphenyl)-5-(3-methoxyphenyl)-1H-1,2,4-triazole, DL-111-IT] was studied in Rhesus monkey. The blood concentration of DL-111-IT was determined by coupled column system HPLC method. Using an aqueous vehicle (20% cremophor EL in saline) DL-111-IT was injected intravenously to monkeys at doses of 25, 12.5 and 6.3 mg.kg-1. Blood drug concentration were measured. Using a programmable calculator the calculated pharmacokinetic parameters were as follows: alpha 1.83 h-1, 4.71 h-1 and 3.61 h-1, beta 0.15 h-1, 0.08 h-1 and 0.09 h-1; T1/2 beta 6.63 h, 10.2 h and 10.1 h; AUC 9.54 micrograms.h-1.ml-1, 3.94 micrograms.h-1.ml-1 and 3.75 micrograms.h-1.ml-1. An oil solution of DL-111-IT was injected intramuscularly in monkeys at doses of 50, 25 and 12.5 mg.kg-1. Its blood concentrations were determined at 0.08, 0.25, 0.5, 0.75, 1, 1.5, 2, 4, 8, 12 and 24 h after administration. From the time vs concentration curve, the pharmacokinetic parameters obtained were as follows: Ka 0.98 h-1, 1.03 h-1 and 1.45 h-1; Ke 0.42 h-1, 0.37 h-1 and 0.60 h-1; T1/2Ke 1.66 h, 1.90 h and 1.16 h; T (peak) 1.52 h, 1.57 h and 1.09 h; AUC 4.86 micrograms.h-1.ml-1, 5.61 micrograms.h-1.ml-1 and 1.74 micrograms.h-1.ml-1.

Mechanism of cigarette smoke condensate induced adhesion of human monocytes to cultured endothelial cells

Cigarette smoking is ranked among the leading risk factors in the etiology of atherosclerotic vascular disease. The mechanisms, however, that link cigarette smoking to increased incidence of atherosclerosis are not understood. The adherence of circulating monocytes to the endothelium, migration into the subendothelium, and subsequent formation of foam cells are principal initial events in the development of atherosclerosis. We therefore determined whether cigarette smoke caused increased adherence of monocytes to endothelial cells and the cellular mechanism of this increased adherence. Cigarette smoke condensate (CSC), the particulate fraction of cigarette smoke derived from 2R1 standard research cigarettes, at a concentration of 25-30 micrograms/ml (average yield of CSC is 26.1 mg/cigarette), augmented (70-90%) basal adherence of human peripheral blood monocytes to a cultured monolayer of endothelial cells derived from bovine aorta (BAEC) and human umbilical vein (HUVEC). There was a concomitant increase in the expression of CD11b ligand on the surface of monocytes as determined by flow cytometry, utilizing FITC conjugated Mab MO-1 (CD11b). However, nicotine (1-15 micrograms/ml) and cadmium sulfate (10 micrograms/ml), constituents of CSC, individually or in combination had no effect either on CD11b expression or adherence of monocytes to endothelial cells. Treatment of HUVEC with CSC for 60 min also resulted in an increased expression of ICAM-1 and ELAM-1 as determined by mean fluorescence intensity of ICAM-1 and ELAM-1 labeled cells in flow cytometric analysis. The CSC induced expression of CD11b in monocytes was optimal at 25-30 min and was inhibited by protein kinase C inhibitors, staurosporine and H-7, and also by baicalein, a lipoxygenase inhibitor. Similarly, CSC induced ICAM-1 and ELAM-1 expression in HUVEC was inhibited by protein kinase C inhibitors. CSC stimulated the adherence of human monocytes but not the monocytic cell lines HL-60, U937, and THP-1 to endothelial cells. The CSC stimulated adherence of human monocytes was inhibited (80%) by MAb to CD11b and 50% by Mab to ICAM-1 and ELAM-1. These results suggest that cigarette smoke particulate constituents activate protein kinase C, leading to increased surface expression of adhesive ligand CD11b on peripheral blood monocytes and counter receptor(s) ICAM-1 and ELAM-1 in endothelial cells. The expression of ligand and counter receptor leads to potentiated adherence of monocytes to endothelial cells, an initial event in the pathogenesis of cigarette smoke induced inflammatory response in the vessel wall.

[Chemoprevention of lung cancer]

Chemoprevention, or pharmacological intervention in healthy individuals at risk of developing cancer, is attracting attention as a potential tool in cancer prevention. Lung cancer, with its high incidence and poor prognosis, is a particularly interesting disease for these studies. The retinoids are a promising group of chemopreventive agents, since they are involved in growth control and are a necessary cofactor for proper activity of a protein receptor which we have shown to be a lung cancer suppressor. Nevertheless, the toxic side effects of retinoids at pharmacological dose present difficulties and current studies are aimed at determining the efficacy of various forms of retinoids and chemoprevention protocols in the target populations.

The frequency of immortalization of human fibroblasts and mammary epithelial cells transfected with SV40 large T-antigen

SV40 T-antigen-expressing human cells generally have an extension of lifespan until a period called "crisis" begins. On rare occasions a clone of cells emerges from the population in crisis and gives rise to an immortalized cell line. The present study compares the frequency of immortalization of cells from two different human lineages, lung fibroblasts and mammary epithelial cells. Most of the T-antigen-transfected clones from both cell types failed to immortalize, however, within those clones which were immortalization-competent the frequency of escape from crisis was found to be much higher (10(-5)) in mammary epithelial cells than in human fibroblasts (3 x 10(-7)). The frequency of escape from crisis in fibroblasts could be increased by chemical mutagenesis or by infection with a defective retrovirus. T-antigen-transfected fibroblasts were uniformly highly aneuploid both before and after crisis. In contrast, many SV40 T-antigen- and human papilloma virus 16 E6- or E6/E7-transfected mammary epithelial clones maintained a subpopulation of pseudodiploid cells prior to crisis, and the immortal cells that emerged following crisis were generally pseudodiploid. The higher frequency of escape from crisis in mammary epithelial cells is best explained by postulating a mutational inactivation of one allele of a critical gene followed by the elimination of the remaining wild-type alleles, with a much higher frequency of this second event in mammary epithelial cells due to their reduced ploidy compared to that in T-antigen-transfected fibroblasts. The results are discussed in terms of the regulation of telomerase activity and the M1/M2 model of cellular senescence.

The effect of sperm preparation methods on the fertilization rate of oocytes micro-inseminated by subzonal sperm injection

Three methods were used to prepare spermatozoa for subzonal injection into mature oocytes. In method A, the washed sperm suspension was incubated for 18 h in modified T6 culture medium. Method B consisted of incubating the sperm suspension for 6 h in regular T6 culture medium. In method C, the sperm suspension was incubated for 6 h in regular T6 culture medium containing 20% (v/v) follicular fluid. The percentages of acrosome-free spermatozoa and fertilization rates were compared for 42 treatment cycles assigned randomly to the three sperm preparation methods. The sperm suspensions prepared by methods A and C each had significantly higher proportions of acrosome-free spermatozoa compared to suspensions prepared by method B. The fertilization rates of oocytes micro-injected with spermatozoa prepared by methods A and C were significantly higher than for method B. Eight clinical pregnancies resulted from 28 cycles in which embryo replacement occurred. We conclude that the fertilization rate following subzonal sperm injection is related directly to the percentage of acrosome-free spermatozoa in the sperm suspension used for microinjection.

[Effects of preimplantation treatment with aspirin and acetaminophen on blastocyst and fetus in rats]

Pregnant rats were treated with ig aspirin (Asp) and acetaminophen (Ace) on d 3 of pregnancy (positive vaginal smear = d 0). Blastocysts were collected on d 4 and evaluated for gross morphology, cell number, micronucleus, and mitotic index. Some rats were killed on d 20 and fetuses were examined for teratogenic effects. On d 4 a reduction of cell number per blastocyst was found in the rats treated with Asp 0.5, 1 g.kg-1, and Ace 1 g.kg-1, while the mitotic index, frequency of micronuclei, and frequency of blastocysts with morphological alterations were increased. The frequency of micronuclei was increased in rats exposed to Ace 0.25 and 0.5 g.kg-1. On d 20 major malformation and embryotoxicity were seen in Asp 0.5, 1, and Ace 1 g.kg-1 groups.

Within-breath variations of forced oscillation resistance in healthy subjects

Respiratory resistance (Rrs) was measured by the forced oscillation technique at 10, 20 and 30 Hz in 54 healthy subjects. The sinusoidal pressure oscillations were applied around the head, rather than at the mouth, so as to minimize transmural pressure across extrathoracic airway walls and the corresponding artefact (Peslin et al., J Appl Physiol, 1985, 59, 1790-1795). The flow (V') and volume (V) dependences of Rrs during the respiratory cycle were analysed by least square regression according to: Rrs = K1 + 2.K2.[V']#- K3.V, where K1 and K2 are Rohrer's constants, and where K3 expresses the (negative) volume dependence of Rrs. The analysis was made separately on the inspiratory and expiratory phases. A good fit was usually found between the data and the model, with a root-mean-square error averaging 15% of the mean Rrs at 10 Hz. At all frequencies K2 and K3 were substantially and significantly larger, and K1 slightly lower during expiration than during inspiration. Rrs, K1 and K3 were minimum at 20 Hz, while K2 exhibited a strong positive frequency dependence. The decrease of Rrs from 10 to 20 Hz was entirely explained by the variations of its linear component, and its increase from 20 to 30 Hz was largely due to its flow dependent component. Both the phasic variations and the frequency dependence of the coefficients suggest that the model is purely descriptive and that coefficients K2 and K3 reflect a number of phenomena, including the variations in glottic aperture during the respiratory cycle.

Within-breath variations of forced oscillation resistance in healthy subjects

Respiratory resistance (Rrs) was measured by the forced oscillation technique at 10, 20 and 30 Hz in 54 healthy subjects. The sinusoidal pressure oscillations were applied around the head, rather than at the mouth, so as to minimize transmural pressure across extrathoracic airway walls and the corresponding artefact (Peslin et al., J Appl Physiol, 1985, 59, 1790-1795). The flow (V') and volume (V) dependences of Rrs during the respiratory cycle were analysed by least square regression according to: Rrs = K1 + 2.K2.[V']#- K3.V, where K1 and K2 are Rohrer's constants, and where K3 expresses the (negative) volume dependence of Rrs. The analysis was made separately on the inspiratory and expiratory phases. A good fit was usually found between the data and the model, with a root-mean-square error averaging 15% of the mean Rrs at 10 Hz. At all frequencies K2 and K3 were substantially and significantly larger, and K1 slightly lower during expiration than during inspiration. Rrs, K1 and K3 were minimum at 20 Hz, while K2 exhibited a strong positive frequency dependence. The decrease of Rrs from 10 to 20 Hz was entirely explained by the variations of its linear component, and its increase from 20 to 30 Hz was largely due to its flow dependent component. Both the phasic variations and the frequency dependence of the coefficients suggest that the model is purely descriptive and that coefficients K2 and K3 reflect a number of phenomena, including the variations in glottic aperture during the respiratory cycle.

Chlamydia trachomatis developmentally regulated protein is homologous to eukaryotic histone H1

Chlamydiae are prokaryotic obligate intracellular parasites that undergo a biphasic life cycle involving an infectious, extracellular form known as elementary bodies and an intracellular, replicating form termed reticulate bodies. We have purified from Chlamydia trachomatis a very basic elementary body-specific protein with an apparent molecular mass of 18 kDa, determined its N-terminal amino acid sequence, and cloned the encoding gene. Sequence analysis of the cloned gene revealed some remarkable properties for its expressed product, including a high lysine content (29%), a correspondingly high pI, and significant homology to the H1 class of eukaryotic histones. Furthermore, a monoclonal antibody to this chlamydial histone analog, termed Hc1, displayed immunoblot and antinuclear specificity suggestive of cross-reactivity to H1 histones. The gene was expressed only during the late stages of the chlamydial life cycle concomitant with the reorganization of chlamydial reticulate bodies into elementary bodies, suggesting that the Hc1 protein plays a role in the condensation of chlamydial chromatin during intracellular differentiation.

Respiratory input and transfer mechanical impedances in patients with chronic obstructive pulmonary disease

Total respiratory input (Zin) and transfer (Ztr) mechanical impedances were measured from 4-30 Hz in 9 patients with severe chronic obstructive pulmonary disease (COPD) and in 12 healthy subjects. Zin was obtained by applying a pressure input around the head to minimize transmural pressure across extrathoracic airway walls, and Ztr was obtained with a pressure input at the chest. In agreement with previous studies total respiratory compliance and inertance were decreased in patients, while effective input resistance was increased and exhibited a negative frequency dependence. Effective transfer resistance (Re(Ztr)) was also increased at all frequencies, and, in some patients, the Re(Ztr)-frequency curve was sigmoid in shape, which was never seen in normals. When Ztr was analysed with a six-coefficient monoalveolar model featuring tissue properties, alveolar gas compliance, and airways properties, the model fitted the data less closely in patients than in normals and, in the former, provided unrealistic coefficients. Such was also the case with a bialveolar model. A better fit with more realistic values for the coefficients was obtained in selected patients with a model where central and peripheral (Rp) airway resistance were separated by a shunt representing airway wall compliance (Cb): Cb was found to range from 0.029-0.062 l.kPa-1 and Rp represented 44-81% of total airway resistance.

Respiratory input and transfer mechanical impedances in patients with chronic obstructive pulmonary disease

Total respiratory input (Zin) and transfer (Ztr) mechanical impedances were measured from 4-30 Hz in 9 patients with severe chronic obstructive pulmonary disease (COPD) and in 12 healthy subjects. Zin was obtained by applying a pressure input around the head to minimize transmural pressure across extrathoracic airway walls, and Ztr was obtained with a pressure input at the chest. In agreement with previous studies total respiratory compliance and inertance were decreased in patients, while effective input resistance was increased and exhibited a negative frequency dependence. Effective transfer resistance (Re(Ztr)) was also increased at all frequencies, and, in some patients, the Re(Ztr)-frequency curve was sigmoid in shape, which was never seen in normals. When Ztr was analysed with a six-coefficient monoalveolar model featuring tissue properties, alveolar gas compliance, and airways properties, the model fitted the data less closely in patients than in normals and, in the former, provided unrealistic coefficients. Such was also the case with a bialveolar model. A better fit with more realistic values for the coefficients was obtained in selected patients with a model where central and peripheral (Rp) airway resistance were separated by a shunt representing airway wall compliance (Cb): Cb was found to range from 0.029-0.062 l.kPa-1 and Rp represented 44-81% of total airway resistance.

Phenotypic differentiation of Cardiobacterium hominis, Kingella indologenes and CDC group EF-4

Eleven strains of Cardiobacterium hominis, two strains of Kingella indologenes and six strains of CDC group EF-4 were characterized. Since all three taxa are oxidase-positive, fastidious gram-negative rods with relatively few positive reactions, they may be easily confused in the microbiological laboratory. Common characteristics are acid production from glucose, aerobic growth in semi-solid agar and very slow anaerobic growth. Group EF-4 is distinguished from the other two species by its capacity to produce catalase and its lack of indole production. Cardiobacterium hominis can be distinguished from Kingella indologenes by its ability to ferment mannitol and sorbitol and by differences in enzyme production. The three taxa also differ considerably with regard to morphological and cultural characteristics.