Optical perfect-shuffle-exchange interconnection network using a liquid-crystal spatial light switch

The perfect-shuffle-exchange interconnection network (e.g., the omega network) is a type of free-space regular multistage interconnection network. An equivalent omega network that consists of left- and right-perfect-shuffle interconnects as well as spatial light switch devices is described. An optical omega network that uses two special polarization prisms and a liquid-crystal spatial light switch is presented. The experimental results of a 8 x 8 omega network are reported. The optical omega network has the features of simple architecture and ease of integration.

The influence of growth hormone on cell proliferation in odontogenic epithelia by bromodeoxyuridine immunocytochemistry and morphometry in the Lewis dwarf rat

For investigation of how growth hormone affects tooth development, bromodeoxyuridine immunocytochemistry and morphometry were used for the study of cell proliferation in odontogenic epithelial cell layers. The number of cells in the S phase, as revealed by this technique, and in mitosis, were counted in Bouin's-perfused and paraffin-embedded undecalcified maxillary incisor enamel organs of normal rats, in growth-hormone-deficient dwarf rats, and in dwarf rats treated with growth hormone (66 micrograms/100 g body wt) twice daily for six days. Significantly fewer labeled nuclei, unlabeled nuclei, and total nuclei of various odontogenic epithelia were found in dwarf rats, but in dwarf rats treated with growth hormone, numbers of labeled nuclei equivalent to normal were found in the internal enamel epithelium, stratum intermedium, and Hertwig root sheath. Moreover, the mitotic index for pre-ameloblasts was 1.64 in normal rats, 0.92 for dwarf rats, and 1.66 for growth-hormone-treated dwarf rats (SD, 0.10). Other parameters--such as the labeling index and the ratio of positive to negative nuclei--were similarly related to GH status. Thus, growth hormone may play a role in the proliferation of the odontogenic epithelia in the rat.

Follow-up of a minute ventilation rate adaptive pacemaker

Although rate adaptive pacemakers are now frequently prescribed, there is limited information regarding long-term follow-up of patients with a pacemaker capable of rate adaptation. We have examined our patients in whom a pacemaker capable of rate adaptation via a sensor that determines minute ventilation has been implanted. After following a group of 42 patients for a mean of 13.2 months we have found this to be a reliable rate adaptive pacing system. The sensor was reliable long term, the system is easy to program, and sensor settings were changed infrequently.

In vitro evaluation of new design lead anchoring sleeves

The purpose of this study was to evaluate various new lead anchoring sleeve designs. These designs were intended to allow coaxial bipolar leads to be tied down and remain securely in position with minimal damage to the lead body, whether tied down with moderate or high tie forces. Axial grooves were made on the outer and/or inner walls of various anchoring sleeve designs. Anchoring sleeves made of extra tear resistant (ETR) platinum catalyzed and peroxide catalyzed (MDX) silicone rubber of various shore, hardness were tested on various Siemens Pacesetter (S-P) and other manufacturers' lead bodies. Tests to slide the sleeves were conducted with the leads in dry and wet conditions, and with and without the Fast-Pass (Siemens Pacesetter, Inc.) coating for lubriciousness. Tie-down deformation of coils was measured from x-ray photos. Mechanical tests and stress calculations were also done to evaluate the mechanical properties of the different lead bodies being tested. The test results showed that compared with existing sleeves, the new design MDX sleeves with axial grooves on the outer wall of the anchoring sleeves provided much lower resultant deformation (62%-84%) on leads when tied down tightly, and exhibited similar sliding forces. Also, it was determined that the MDX anchoring sleeves provided much improved slip forces of two to three times higher than the ETR sleeves. Tie-down damage can also be significantly reduced by strengthening lead bodies. With the protection of the new sleeves, the tie-down damage of S-P leads was the lowest among all the manufacturers' polyurethane or silicone leads tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Erythrocyte membrane lipid composition fluidity in patients with essential hypertension

The lipid composition and fluidity of erythrocyte membrane in 36 patients with essential hypertension were examined. The results showed that either cholesterol/phospholipid molar ratio or lipid peroxides content was significantly increased (P < 0.01 or 0.001), and the superoxide dismutase activity, contents of four classes of phospholipids, i.e., phosphatidyl ethanolamine, phosphatidylcholine, phosphatidylserine and sphingomyelin of erythrocyte membrane, and lipid fluidity were significantly decreased (P < 0.05, < 0.01 or < 0.001) as compared with those in 35 normotensive control subjects. These results suggested that the changes of lipid composition and fluidity might associate with the decreased activities of cation transport systems in cell membranes and play an important role in the pathogenesis of essential hypertension.

[Isolation and characterization of mutactimycin-producing mutant]

Natural non-antibiotic producing Streptomyces sp. 1254 was mutagenized by UV irradiation and two active mutants were isolated. Mutant 113 produced novel anthracycline compounds designated mutactimycins. Mutactimycin A was active against the bacteriophage of Bac. subtilis and some viruses in tissue culture. The mutant 2-6 synthesized a basic water-soluble antimicrobial antibiotic. Chemical analysis of the whole cell hydrolysate and the morphological characterization showed that the strain 1254 and its mutant 2-6 were of chemotype I, belonging to the genus of Streptomyces, and the mutant 113 was of chemotype IV without mycolic acid. Co-synthesis test of strain 1254 and a blocked mutant of strain 113 gave the active compounds identical with mutactimycins. Using the actI gene as a probe, the Southern hybridization revealed homology between the actinorhodin polyketide biosynthase gene and the total DNA of the strain 1254. Based on these data it was deduced that Streptomyces sp. 1254 should have a biosynthesis pathway for mutactimycin, but some of its genes might fail in expression and mutagenesis would make the silent gene(s) active.

Growth hormone regulates nucleolar organizer regions during odontogenesis in the rat

Nucleolar organizers are major sites of ribosomal RNA synthesis and provide an index of transcriptional activity. In order to further define growth hormone actions on nucleolar organizer regions in tooth forming cells, hypophysectomized rats treated with growth hormone for 4 and 24 h, hypophysectomized and sham-operated animals were used. After demineralization and standard paraffin embedding, longitudinal sections of maxillary incisors were stained by a silver stain technique to reveal nucleolar organizer regions. The area of these regions per nucleus was measured using a modified microdensitometer. Analyses of variance of the resulting data showed that preameloblasts and preodontoblasts have greater silver stained nucleolar organizer region values than ameloblasts and odontoblasts. Hypophysectomy reduced and growth hormone partly restored the level of nucleolar organizer regions in preameloblasts and preodontoblasts, but not in mature ameloblasts or odontoblasts. In the case of the younger preameloblasts and preodontoblasts, the effect of growth hormone was seen within 4 h of growth hormone injection. In conclusion, rRNA synthesis, as revealed by the specific silver staining of nucleolar organizer regions in tooth forming cells, appears to be regulated by growth hormone over a relatively short time frame.

Casein kinase II protein kinase is bound to lamina-matrix and phosphorylates lamin-like protein in isolated pea nuclei

A casein kinase II (CK II)-like protein kinase was identified and partially isolated from a purified envelope-matrix fraction of pea (Pisum sativum L.) nuclei. When [gamma-32P]ATP was directly added to the envelope-matrix preparation, the three most heavily labeled protein bands had molecular masses near 71, 48, and 46 kDa. Protein kinases were removed from the preparation by sequential extraction with Triton X-100, EGTA, 0.3 M NaCl, and a pH 10.5 buffer, but an active kinase still remained bound to the remaining lamina-matrix fraction after these treatments. This kinase had properties resembling CK II kinases previously characterized from animal and plant sources: it preferred casein as an artificial substrate, could use GTP as efficiently as ATP as the phosphoryl donor, was stimulated by spermine, was calcium independent, and had a catalytic subunit of 36 kDa. Some animal and plant CK II kinases have regulatory subunits near 29 kDa, and a lamina-matrix-bound protein of this molecular mass was recognized on immunoblot by anti-Drosophila CK II polyclonal antibodies. Also found associated with the envelope-matrix fraction of pea nuclei were p34cdc2-like and Ca(2+)-dependent protein kinases, but their properties could not account for the protein kinase activity bound to the lamina. The 71-kDa substrate of the CK II-like kinase was lamin A-like, both in its molecular mass and in its cross-reactivity with anti-intermediate filament antibodies. Lamin phosphorylation is considered a crucial early step in the entry of cells into mitosis, so lamina-bound CK II kinases may be important control points for cellular proliferation.

Chimeric DNA-RNA hammerhead ribozymes have enhanced in vitro catalytic efficiency and increased stability in vivo

Subsequent to the discovery that RNA can have site specific cleavage activity, there has been a great deal of interest in the design and testing of trans-acting catalytic RNAs as both surrogate genetic tools and as therapeutic agents. We have been developing catalytic RNAs or ribozymes with target specificity for HIV-1 RNA and have been exploring chemical synthesis as one method for their production. To this end, we have chemically synthesized and experimentally analyzed chimeric catalysts consisting of DNA in the non-enzymatic portions, and RNA in the enzymatic core of hammerhead type ribozymes. Substitutions of DNA for RNA in the various stems of a hammerhead ribozyme have been analyzed in vitro for kinetic efficiency. One of the chimeric ribozymes used in this study, which harbors 24 bases of DNA capable of base-pairing interactions with an HIV-1 gag target, but maintains RNA in the catalytic center and in stem-loop II, has a sixfold greater kcat value than the all RNA counterpart. This increased activity appears to be the direct result of enhanced product dissociation. Interestingly, a chimeric ribozyme in which stem-loop II (which divides the catalytic core) is comprised of DNA, exhibited a marked reduction in cleavage activity, suggesting that DNA in this region of the ribozyme can impart a negative effect on the catalytic function of the ribozyme. DNA-RNA chimeric ribozymes transfected by cationic liposomes into human T-lymphocytes are more stable than their all-RNA counterparts. Enhanced catalytic turnover and stability in the absence of a significant effect on Km make chimeric ribozymes favorable candidates for therapeutic agents.

Interleukin 2 production and its relationship with T lymphocyte subsets in patients with obstructive jaundice

Sepsis remains a major risk in the high mortality and morbidity after surgery for obstructive jaundice. The reasons for the increased susceptibility to infection are unknown. This study examined interleukin 2 (IL-2) production and the lymphocyte response to PHA mitogen in 31 patients with obstructive jaundice. Among them, 18 patients were simultaneously investigated by enumeration of T lymphocyte subsets in peripheral blood with APAAP technique. The results showed that the patients had significantly decreased IL-2 production and lymphocyte response to PHA mitogen. The percentage of Leu 3a (helper/inducer T cell) in the patients was significantly lower than that in normal controls. Leu 3a/Leu 2a (suppressor/cytotoxic T cell) ratio was significantly lower in these patients. The reduction of IL-2 production correlated significantly with the suppression of lymphocyte proliferation but not with the percentage of Leu 3a cells. From these results, it may be suggested that the reduction of IL-2 production in the patients with obstructive jaundice is an important reason for the suppression of T lymphocyte proliferative response, not merely a reflection of the decrease of helper T cells.

Effects of surgical trauma on interleukin 2 production and interleukin 2 receptor expression

To elucidate the mechanism of immunologic abnormalities induced by surgical trauma, we measured interleukin 2 (IL-2) production and IL-2 receptor expression in peripheral blood mononuclear cells from 16 patients with cholelithiasis. Compared with preoperative levels, IL-2 production and IL-2 receptor expression were significantly reduced on postoperative day 4, and the reduction was consistent with the suppression of lymphocyte proliferative response to phytohemagglutinin.

Physiologic comparison and validation of Stairobic stepping with bench stepping

To compare the oxygen cost of submaximal exercise on the Stairobic stepping (SS) machine with bench stepping (BS), 12 healthy men and women (mean age 23 years) underwent six different five minute exercise bouts that were randomly assigned. Tests were conducted using standard open circuit calorimetry. SS at 40 and 60 st/min was equal to BS at 20 st/min and SS at 80 st/min was equal to BS at 30 st/min for VE and RER. VO2 was equal at 20 st/min (BS) and 60 st/min (SS), and 30 st/min (BS) and 80 st/min (SS). Stairobic MET (SM) displayed values over-estimated actual MET (AM) values at the two lowest SS rates and under-estimated the AM value at the highest SS rate. Forty-eight observations of the MET response of SS were conducted and analyzed (BMDP2R) in a forward stepping solution. The multiple regression equation calculated for AM was: AM = -0.567 + -0.012 (WT) + 0.063 (rate) + 0.612 (SM) with an adjusted R2 of 0.82 and a SEE of 0.90. The physiologic cost of BS was approximately equal to SS at two to three times the BS rate of stepping.

Frequent spontaneous sister chromatid exchange in hepatocytes of transgenic mice harboring the SV40-T antigen gene

In order to shed light on the causal mechanisms of hepatocarcinogenesis in the transgenic mouse into which the albumin-promotor-regulated SV40-T antigen gene has been introduced (T+ mouse), and especially on the frequent chromosomal aberrations seen in cultured hepatocytes and hepatocellular neoplasms derived from such animals, the frequency of sister chromatid exchange (SCE) and karyotype abnormalities were investigated in a hepatocyte primary culture system. Cells were obtained through collagenase perfusion from T+ mice at 16-18 days of age, when no morphological changes are apparent, and from nontransgenic littermates, and cultured in the presence of bromodeoxyuridine. SCE was seen in transgenic hepatocytes twice as frequently as in their normal counterparts. No karyotype abnormalities in terms of numerical change or gross aberration were detected at this phase. The results thus suggest mutagenic properties for the T antigen, which may play an important role in hepatocarcinogenesis in this transgenic mouse.

[Study on epidemic factors of the decline of cervical cancer mortality in Shandong province]

It is well known that the decline in the incidence or mortality rates of cervical cancer was very significant in the eighties as compared with in the seventies in China. In Shandong province the mortality of cervical cancer was reduced by 76.3 percent during from 1974 year to 1989 year. According to the survival time of patients with cervical cancer in Cangshan county showed that the decline in the mortalities was due to cut down the incidences of it. A birth cohorts study of mortality of the disease was made in the period time of from 1970 to 1989 in Qixia county. The results of which indicated that the cohorts of women who reached puberty after 1949 have much lower rates of cervical cancer than the cohorts of women who reached sexual maturity before that time. The correlation analysis showed the main reason for the decline was related to the elimination of the venereal diseases by the end of 1964 year. The birth control programme having been carried out since the beginning in the sixties also found in relation to the decline of cervical cancer in the eighties.

Optimal low dosage of acetylsalicylic acid (ASA) for the prevention and treatment of ischemic cerebrovascular disease in geriatric patients

A series of 108 geriatric patients with ischemic cerebrovascular disease were treated with low dose aspirin (acetylsalicylic acid, ASA). Daily doses of 100 mg, 50 mg and 25 mg were administered to three groups of 36 patients. Changes in platelet aggregation responses were dynamically observed in 64 (22 normal subjects, 42 patients). Monitoring of 22 normal subjects revealed inhibition of platelet aggregation at a dose of 300 mg or 100 mg which could last as long as 7 days. This suggests that 100 mg or less could be clinically effective. Satisfactory inhibitory effects on platelet aggregation were observed in all three groups, with 14 patients in each group given daily doses of 100 mg, 50 mg and 25 mg during four weeks' observation. The most effective inhibition was obtained in the 50 mg group. Therefore, the authors recommend 50 mg/d as the optimal dosage for low dose aspirin therapy in geriatric patients.

Virus infection and hand papular dermatoses in young children

Four strains of enterovirus and 1 strain of adenovirus were isolated from stool and pharyngeal swabs by inoculation into primary human embryonic kidney cell culture in 25 cases of dorsum manus infantile papular dermatitis. Two strains of Coxsackie A-9 virus and 1 strain of Echovirus-25 were identified. With the isolated virus as antigen, a matched pair study by sera antibody test was carried out in 43 children with papular dermatitis and 40 normal individuals as controls. In 26 cases of Coxsackie A-9 virus positive papular dermatitis, a 4-fold rise (> 1:1.6) in the relative serum antibody was observed in 80.77%, while no high levels were observed in patients with Echovirus-25 and adenovirus dermatitis (< 1:16). The authors can reasonably conclude that epidemic Coxsackie A-9 virus infection is obviously related to infantile papular dermatitis and is probably the main cause of the disease.

Carcinoma arising in Barrett's esophagus

During the period 1971 and 1990, 500 patients underwent resection for carcinoma of the esophagus, 51 of whom had an associated Barrett's esophagus. Of these, 49 had adenocarcinoma and two had squamous cell carcinoma. Barrett's carcinoma accounted for 23.7 percent of the surgically treated adenocarcinomas during this period. Reflux symptoms were present in 13 patients preoperatively. Tumors developed in four patients who had undergone previous antireflux operation and in two patients on the surveillance program. By postresection staging, 18 patients had stage II tumors and 33 patients had stages III and IV tumors. Stage and length of the tumor were the only prognostic determinants. The overall 90 day hospital mortality rate was 17.6 percent. The hospital mortality rate before 1986 was 22.9 percent, but decreased to 6.3 percent in the last five years. The one, two and five year survival rates were 45.9, 25.0 and 13.6 percent, respectively. The five year survival rate was significantly greater for patients with stage II (25 percent) than for patients with stages III and IV (4.5 percent) (p less than 0.05) and for tumor length less than 6 centimeters (21 percent) than for tumors greater than 6 centimeters (zero percent; p less than 0.001).

Effects of dietary protein deficiency on mineral metabolism and bone mineral density

The effects of dietary protein restriction on mineral and bone metabolism are uncharacterized. We studied growing rats fed a diet low in protein (5%) for 4, 6, and 8 wks (n = 10 animals/group) and compared them with animals pair-fed with a protein-replete (18%) diet. The low-protein diet rapidly induced a profound hypocalciuria that persisted for greater than or equal to 8 wk. Serum calcium and phosphorus concentrations were not affected but serum total and free 25-dihydroxyvitamin D concentrations as well as gastrointestinal calcium absorption were lower in the low-protein animals. Skeletal dimensions were reduced in the protein-deprived rats but there were no significant differences in bone mineral content between control and low-protein animals at 4, 6, and 8 wks. Hence, dietary protein deprivation resulted in slower growth but bone mineral density was maintained when there was a marked reduction in urinary calcium excretion.

Antigenic diversity of Rickettsia conorii

Analysis of seven strains designated as Rickettsia conorii for reactivity with a panel of 12 monoclonal antibodies to surface-protein epitopes of spotted fever group rickettsiae and by Western immunoblotting with standard serotyping sera revealed remarkable antigenic diversity. Rickettsial strains from France, Morocco, Ethiopia, Kenya, South Africa, India, and the USSR differed from one another in reactivity with at least one and as many as five monoclonal antibodies. Simko and Indian strains were similar to one another and differed substantially from other R. conorii strains. All seven strains reacted with three R. conorii-specific monoclonal antibodies. Western immunoblotting demonstrated a major 120-kD protein and a major 135-kD protein in all strains. The principal differences were the presence of a major undenatured 130-kD protein in all strains except Indian and Simko, which had an analogous protein of 124 kD. Immunodominant antigenically related, heat-denatured protein bands of 170 kD (Malish 7 strain), 175 kD (Manuel strain), and 190 kD (Kenya tick typhus, Indian, and Simko strains) were not detected in the M-1 and Moroccan strains. This antigenic diversity is greater than that previously reported for other spotted fever group rickettsial species, suggesting that R. conorrii is an older species than R. rickettsii with a longer period of time for evolutionary divergence.

Gene-centromere linkage mapping by PCR analysis of individual oocytes

We describe a general method of determining the recombination fraction between a polymorphic locus and the centromere in any species where single oocytes can be obtained. After removal of the first polar body, each oocyte is analyzed by PCR. The frequency of oocytes heterozygous at the polymorphic locus is used to estimate the recombination fraction. We estimate a recombination fraction of 0.15 between the mouse major histocompatibility complex (H-2) and the centromere of chromosome 17.

A genetic linkage map of 96 loci on the short arm of human chromosome 3

We constructed a genetic map of 96 loci on the short arm of human chromosome 3 (3p) in 59 families provided by the Centre d'Etude du Polymorphisme Humaine (CEPH). Twenty-nine continuously linked loci were placed on the map with likelihood support of at least 1000:1; one locus, D3S213, was placed on the map with likelihood support of 871:1; D3Z1, an alpha satellite centromeric repeat probe, was placed on the map with likelihood support of 159:1; 65 loci were assigned regional locations. The average heterozygosity of the uniquely ordered markers was 49%. The map extends from 3p26, the terminal band of 3p, to the centromere (from D3S211 to D3Z1). Multipoint linkage analysis indicated that the male, female, and sex-averaged maps extend for 102, 147, and 116 cM, respectively. The mean genetic distance between uniquely ordered loci on the sex-averaged map was 4.0 cM. Probe density was greatest for the region of 3p between D3F15S2e and the telomere. The sex-averaged map contained two intervals greater than 10 cM. Seventeen probes were localized by fluorescence in situ hybridization. The loci described in this report will be useful in building an integrated genetic and physical map of this chromosome.

Expression of growth hormone receptor by immunocytochemistry in rat molar root formation and alveolar bone remodeling

Growth hormone (GH) may regulate tooth formation and bone remodeling associated with tooth eruption. This study reports the distribution of growth hormone receptor/binding protein in developing rat molars and adjacent alveolar bone by immunocytochemistry using well-characterized anti-growth hormone receptor monoclonal antibodies. These tissues represent an excellent model for studying the ontogenic changes that occur in odontogenic and osteogenic cells, as these cells are found in linear arrays displaying the various stages of morphological and functional differentiation, and differentiated function. Immunoreactivity was first seen in precementoblasts in contact with the epithelial root sheath, and preodontoblasts. However, growth hormone receptor immunoreactivity was associated primarily with the cytoplasm of odontogenic and osteogenic cells forming their respective matrices. Thus, cementoblasts and odontoblasts at sites of new matrix formation showed intense immunoreactivity whereas cementocytes and mature odontoblasts at later stages of tooth development were nonreactive. Osteoblasts engaged in intramembranous ossification in the alveolar bone were positive, although osteocytes and endosteal cells were immunonegative. Osteoclasts at sites of alveolar bone remodeling resorption were also immunopositive. These patterns of receptor expression parallel the ontogenic sequences of odontogenic and osteogenic cells and suggest that GH promotes the functional state of these cells. Our results also imply that GH may influence differentiation or differentiated functions associated with odontogenesis, osteogenesis, and bone remodeling independent of systemic insulin-like GF-I.

Purification and characterization of a casein kinase 2-type protein kinase from pea nuclei

Almost all the polyamine-stimulated protein kinase activity associated with the chromatin fraction of nuclei purified from etiolated pea (Pisum sativum L.) plumules is present in a single enzyme that can be extracted from chromatin by 0.35 molar NaCl. This protein kinase can be further purified over 2000-fold by salt fractionation and anion-exchange and casein-agarose column chromatography, after which it is more than 90% pure. The purified kinase has a specific activity of about 650 nanomoles per minute per milligram protein in the absence of polyamines, with either ATP or GTP as phosphoryl donor. Spermidine can stimulate its activity fourfold, with half-maximal activation at about 2 millimolar. Spermine and putrescine also stimulate activity, although somewhat less effectively. This kinase has a tetrameric alpha 2 beta 2 structure with a native molecular weight of 130,000, and subunit molecular weights of 36,000 for the catalytic subunit (alpha) and 29,000 for the regulatory subunit (beta). In western blot analyses, only the alpha subunit reacts strongly with polyclonal antibodies to a Drosophila casein kinase II. The pea kinase can use casein and phosvitin as artificial substrates, phosphorylating both the serine and threonine residues of casein. It has a pH optimum near 8.0, a Vmax of 1.5 micromoles per minute per milligram protein, and a Km for ATP of approximately 75 micromolar. Its activity can be almost completely inhibited by heparin at 5 micrograms per milliliter, but is relatively insensitive to concentrations of staurosporine, K252a, and chlorpromazine that strongly antagonize Ca(2+) -regulated protein kinases. These results are discussed in relation to recent findings that casein kinase 2-type kinases may phosphorylate trans-acting factors that bind to light-regulated promoters in plants.

Hormonal profile of the menstrual cycle in Chinese women after tubal sterilization

Ten women after tubal sterilization were studied for the hormonal profile of the menstrual cycle. They had undergone sterilization procedures, on the average 5.3 years (range 1.5-10 years) earlier. The serum concentrations of LH, FSH, prolactin, estradiol and progesterone were measured by RIA in daily blood samples of a complete menstrual cycle. Another ten normal women were studied at the same time and were used as the control group. There were no significant differences in the hormonal patterns of the menstrual cycle between the two groups. There was a significantly lower LH level in the early luteal phase of the tubal ligation group compared to the control group. Also, a significantly lower E2 luteal peak compared to the preovulatory peak was observed in the tubal ligation group. The physiological significance of these minor changes is not clear. Only one out of ten women in the tubal ligation group, who had undergone sterilization 1.5 years prior, showed a deficiency in luteal function, but her ovulatory function and menstrual cycle appeared normal. This study indicates that normal hormonal profiles are retained after tubal sterilization.

Sperm typing allows accurate measurement of the recombination fraction between D3S2 and D3S3 on the short arm of human chromosome 3

The interval between the D3S2 and D3S3 loci on human chromosome 3p is a frequent site of deletions in a number of different cancers and contains the most common fragile site in man. Both loci have been physically mapped to 3p but because heterozygosity for D3S3 is so infrequent, recombination between them could not be determined accurately by using family studies. Sperm typing can measure recombination between DNA polymorphisms even in a single individual and thus can make use of polymorphisms with a low PIC. The recombination fraction between D3S2 and D3S3 was estimated to be 0.28 based on analyzing 189 and 77 sperm from two doubly heterozygous donors, respectively. These results demonstrate one of the ways in which sperm typing can complement pedigree analysis in constructing genetic maps.

Genomic typing of hepatitis C viruses present in China

Hepatitis C virus (HCV) genomic clones were obtained from the serum of Chinese HCV carriers using a polymerase chain reaction-based approach. Consensus sequences were derived from (1) the structural region (nt 1-1543) for one carrier, (2) the hypervariable region V (nt 1156-1233) from four carriers and (3) region V3 from four carriers. Region V3, located in the nonstructural domain NS5 (nt 7066-7137), has been previously shown to be a particularly good marker for the genomic typing of HCV isolates [Inchauspe et al., Proc. Natl. Acad. Sci. USA 88 (1991) 10292-10296]. Comparison of these sequences with sequences from geographically distinct HCV isolates indicates that Chinese HCV strains are closely related to, though distinguishable from, Japanese prototype strains. One amino acid motif, GGAA, located in region V, was found to be conserved only among Chinese isolates. This may define a new subgroup among HCV isolates.

Gamma delta T-cell receptor repertoire in acute multiple sclerosis lesions

Gamma delta T cells are a distinct lymphocyte population that can exhibit reactivity with heat shock proteins over-expressed at inflammatory sites. As gamma delta T cells may be involved in the central nervous system (CNS) inflammatory process in multiple sclerosis (MS), we examined T-cell populations in MS plaque tissue by quantitative immunohistochemistry and sequence analysis of T-cell antigen receptor (TCR) delta chains. Gamma delta T cells that express the variable (V) gene segments V delta 1, V delta 2, and V gamma 2 (V gamma 9) were found to accumulate in acute, demyelinating MS plaques and appeared to have undergone clonal expansion, most likely because of recognition of a specific CNS ligand. Further, 60-kDa and 90-kDa heat shock proteins (hsp60 and hsp90), which may be target antigens for autoreactive gamma delta T cells, were found to be expressed in normal CNS tissue and overexpressed in acute MS plaques. In acute plaques, hsp60 was found in foamy macrophages, while hsp90 was detected in reactive astrocytes. These results provide evidence for a role of gamma delta T cells in active stages of MS.

Characterization of rickettsial attachment to host cells by flow cytometry

The mechanisms of rickettsial attachment have been studied by measuring quantitative changes in rickettsial binding to host cells by flow cytometry after different treatments of the rickettsiae and host cells. Time-dependent binding of Rickettsia conorii to host cells was demonstrated by the increasing intensity of host cell surface fluorescence of rickettsia-host cell combinations when examined with a rickettsia-specific monoclonal antibody. More than 70% of host cells had intensity of fluorescence above the threshold value after 10 min of incubation, owing to rickettsiae bound to the cell surface, and the greatest fluorescence intensity indicative of binding occurred at 20 min. The binding kinetics was rickettsial dose dependent. The binding of rickettsiae to host cells was greatly decreased when host cells or rickettsiae were treated with 1% paraformaldehyde for 30 min or 0.25% trypsin for 5 or 15 min, respectively. Rickettsiae that were heated at 56 degrees C for 15 min lost more than 80% of their ability to attach to host cells. R. rickettsii, an organism closely related to R. conorii, competitively inhibited the attachment of R. conorii (51% inhibition when mixed in equal numbers). These results indicate that the rickettsial binding structures are trypsin and heat sensitive and likely to be surface proteins.

T cell receptor V alpha-V beta repertoire and cytokine gene expression in active multiple sclerosis lesions

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system with presumed autoimmune etiology. A recent study has suggested the presence of a restricted T cell receptor (TCR) V alpha repertoire in MS lesions. The presence of such a restricted TCR repertoire at the site of inflammation would have important consequences for the pathogenesis and the ultimate treatment of MS. To further characterize the TCR V alpha and V beta repertoire in MS plaque tissue, we examined a series of 26 histologically well-characterized central nervous system (CNS) tissue specimens from six MS patients as well as samples from five normal postmortem cases and a case of subacute sclerosing panencephalitis. RNA was extracted from frozen sections and cDNAs were amplified by polymerase chain reaction using primers for TCR V alpha (V alpha 1-18) and V beta (V beta 1-19) gene families. This analysis demonstrated a broad TCR V alpha-V beta repertoire in active lesions, while fewer TCR V genes were detected in chronic plaques and control samples. Even though a large number of TCR V alpha and V beta gene segments were present in the majority of active lesions, there were clear differences in the TCR repertoire between plaques from the same case, suggesting that local events influence the TCR repertoire at the level of T cell recruitment or T cell expansion. Examination of cytokine mRNAs demonstrated that IL-1 mRNA was present in the majority of acute and subacute plaques, while IL-2 and IL-4 mRNA were detected in only a few acute lesions. These data demonstrate that the TCR repertoire in MS plaques is polyclonal. However, autoreactive alpha/beta T cells thought to be critical in the initiation of the inflammatory process probably represent a minor fraction of T cells in active MS plaques and may use a limited number of TCR V gene segments for recognition of the autoantigen.

Cloning of two adult hamster globin cDNAs (alpha and beta major)

A cDNA library was prepared from poly(A) mRNA extracted from adult anemic hamster spleen erythroid cells. cDNA clones containing inserts coding for adult alpha and beta major globin chains were isolated. Their identity was confirmed by (a) translation of hybrid selected mRNA and (b) nucleotide sequence analysis of the inserts and comparison to the adult globin cDNAs of mouse, rabbit and human. Availability of sequences for embryonic (Li et al. (1992) Biochim. Biophys. Acta 1130, 218-220) and adult globin cDNAs (this report) will aid in investigations of the molecular mechanisms involved in the globin ontogeny of hamsters.

[Epidemic investigation of genital mycoplasma hominis infection in women]

The genital mycoplasma hominis infection in women was investigated at Xiaguan district, Nanjin in June, 1990. Leucorrheas from 722 women were tested with ELISA for the antigen of M. hominis. The prevalences of genital M. hominis were not statistically different among age and occupation groups. Women having pregnancy more than three times had a significantly higher infection rate, it is suggested that induced abortion might provide chances of the infection. The prevalence was significantly different among groups of various contraceptive means, it is lower in the group of contraceptive condom and higher in the group of intrauterine device.

Cloning and sequence analysis of two embryonic beta-like globin cDNAs (y and z) of hamster

A cDNA library was prepared from poly(A) mRNA extracted from 9-day hamster-yolk-sac erythroid cells. Two clones containing inserts coding for embryonic beta-like z or y globin-chains were isolated. Their identity was confirmed by (a) translation of hybrid selected mRNAs and (b) nucleotide sequence analysis of the inserts and comparison to the embryonic beta-like globin genes of Balb/c mouse. Availability of sequences for embryonic and adult globin cDNAs will aid in investigations of the molecular mechanisms of the globin switch in hamster YSEC.

Failure of the lipid peroxidation inhibitor, U74006F, to prevent postischemic selective neuronal injury

The lipid peroxidation inhibitor, U74006F, was tested for neuroprotective properties using the rat four-vessel occlusion model. Adult Wistar rats (136) were randomized to receive pretreatment with either vehicle or U74006F, and exposed to either 15 min (n = 103) or 5 min (n = 33) of transient but severe forebrain ischemia. Surviving criterial animals were reperfused for 72 h, and in the multidose experiments, animals were injected with repeated doses of U74006F or vehicle during the reperfusion period. Vehicle-treated animals exposed to 15 min of ischemia sustained 60 +/- 35% (n = 16) CA1 pyramidal cell necrosis whereas U74006F-treated animals lost 61 +/- 30% (3 mg/kg, n = 9), 42 +/- 35% (10 mg/kg, n = 15), 62 +/- 28% (5 x 10 mg/kg, n = 10), and 74 +/- 30% (8 x 10 mg/kg, n = 10) of CA1 pyramidal cells. No improvement was seen in the injury to cortex or striatum with either pre- or pre- and posttreatment with U74006F. For animals suffering 5 min of transient forebrain ischemia, vehicle-treated rats lost 19 +/- 26% (n = 14), whereas U74006F-treated (8 x 10 mg/kg) animals lost 36 +/- 39% (n = 15) of CA1 neurons. In addition, no protection was discerned in the mildly injured striatum or cortex of these animals. Given the potent effect of U74006F in inhibiting iron-dependent lipid peroxidation in vitro, we question the importance of oxy radicals in the mechanism of postischemic selective neuronal injury in vivo.

Molecular aspects of the calbindins

Studies from our laboratory concerning regulation of calbindin include regulation by 1,25-dihydroxycholecalciferol [1,25(OH)2D3], receptor regulation as a possible mechanism for modulating calbindin's response to hormone, tissue specific regulation and regulation by factors other than 1,25(OH)2D3. With regard to receptor regulation, we found that the induction of calbindin mRNA in intestine and kidney by 1,25(OH)2D3 is not accompanied by a corresponding alteration in vitamin D receptor (VDR) mRNA in the vitamin D-deficient, low calcium rat. However, in the vitamin D-replete rat, administration of 1,25(OH)2D3 results in an induction of both calbindin and VDR mRNA in these tissues. These results suggest the presence of an inhibitor of 1,25(OH)2D3-mediated receptor up-regulation in the vitamin D-deficient, low calcium animal. Glucocorticoids can also regulate calbindin gene expression. Dexamethasone treatment (50 micrograms.100 g body weight-1.d-1 for 4 d) results in a 75% decrease in rat intestinal calbindin-D9k mRNA. This decrease may be related to the inhibition of intestinal calcium absorption previously observed after glucocorticoid administration. Kidney calbindin-D28k mRNA is unaffected by glucocorticoid treatment, indicating tissue specificity of the glucocorticoid response. To evaluate more precisely the means whereby 1,25(OH)2D3 and other modulators can influence calbindin gene expression, we isolated the chromosomal gene for calbindin-D28k by screening a mouse genomic library in cosmid. Ros 17/2.8 cells were transfected with recombinant plasmids in which the mouse calbindin promoter is fused to the reporter gene encoding chloramphenicol acetyltransferase. Deletion studies have enabled us to identify sequence elements in the mouse calbindin-D28k gene that confer basal activation and a hormone inducible response.

Study on the pathogenic factors of Kashin-Beck disease

Kashin-Beck disease (KBD) is a chronic osteoarthritic disease, endemic in parts of China. Its etiology is unknown. Selenium deficiency, high concentration of organic matter (mainly fulvic acid) in drinking water, and severe contamination of grain by fungi have been proposed environmental causes. Free radicals, possible mediators between the environmental factors and origin of KBD, have been studied in this work. Drinking water from KBD-affected areas contains a higher level of semiquinone radicals than that from disease-free areas. In animal experiments, fulvic acid (FA) accumulated in the skeletal system as semiquinone radicals. Contamination of grain by Fusarium oxysporum or Alternaria alternata significantly increased the content of semiquinone radicals. Furthermore, corn grown in endemic areas had a higher content of radicals than that from disease-free areas. The g factor values for these radicals from contaminated corn were about 2.0040, in the range of semiquinone radical. In monolayer culture of human embryonic chondrocytes, FA and aqueous extracts of grain contaminated by Fusarium injured the chondrocytes and enhanced lipid peroxidation. Selenite and superoxide dismutase (SOD) protected the cells from injury by these toxins and reduced lipid peroxide. Lower glutathione peroxidase activities and higher levels of lipid peroxidation were also found in the children living in KBD-affected regions. Thus, FA and the mycotoxin, which are seen as exogenous free-radical carriers, are important environmental factors in the pathogenesis of Kashin-Beck disease; and selenium, vitamin C, and vitamin E, which inhibit free-radical formation, are considered to be protective.

Effects of p-chlorophenylalanine on thermoregulation and sleep in rats

Sleep/waking and body temperature (Tb) were recorded in male rats in a 12:12 light-dark photoperiod at one of 3 ambient temperatures (Ta's): 20, 30, or 32 degrees C. After adaptation to the sleep recording chamber for at least 48 h, the rats were injected with saline at the beginning of lights-on (day S1). Twenty-four hours later (day P1), they were injected with PCPA (300 mg/kg, i.p.) and recordings continued for 4 more days (P2-P5). At these Ta's, hypothalamic 5-HT was depleted by 66-75% 30 h post-PCPA. Changes in both amplitude and acrophase of Tb depended on Ta. Compared to S1, amplitude was reduced on P2-P4 at 20 degrees C and on P3-P4 at 30 degrees C. Acrophase was advanced on P1-P3 at Ta 20 degrees C only. Sleep variables were generally independent of Ta and largely unchanged in the dark. In the light, amounts of slow-wave sleep (SWS) were depressed on P2-P4, number of bouts decreased on P3-P5 and percent nocturnality decreased on P2-P5. Bout length was depressed on P2 and lengthened on P4-P5. Acrophase was delayed on P2-P4 at Ta 30 degrees C. Amounts of rapid-eye-movement sleep (REMS) were depressed on P1-P3. REMS bout length decreased on P1-P3. The decreases in number of REMS bouts seen on P1-P3 depended on Ta. Changes in percent nocturnality and acrophase of REMS were minor. Waking----SWS transitions decreased on P3-P5 while SWS----REMS transitions were reduced on P1-P2. These results suggest that PCPA affects circadian aspects of both Tb and sleep, that 5-HT is important in the initiation of SWS bouts, and finally that the mechanisms by which 5-HT depletion affects Tb, SWS and REMS are different.