[Gingival crevicular aspartate aminotransferase levels in periodontitis patients before and after periodontal treatment]

Gingival crevicular fluid samples were collected from 296 teeth from 40 subjects, including 19 rapidly progressive periodontitis (RPP), 8 chronic adult periodontitis (CAP), 7 marginal gingivitis (MG) and 6 healthy subjects (H). The activities of aspartate aminotransferase (AST) in each sample were tested. The results were as follows: (1) The two groups with destructive periodontal disease (RPP and CAP) had greater GCF-AST levels than that from the two non-destructive groups (MG and H). (2) The GCF-AST activities showed significant positive correlations with clinical periodontal parameters, such as probing depth, attachment loss, bleeding index and suppuration. (3) Four weeks after thorough full-mouth root planing, both clinical parameters and GCF-AST levels decreased significantly. The present study suggests that GCF-AST activity might be a sensitive and objective marker for detection of periodontal tissue destruction and inflammation.

Construction of hybridomas secreting monoclonal antibody against sweet potato feathery mottle virus and use of antibody for detection of SPFMV

Two hybridomas stably secreting monoclonal antibodies (McAb) against sweet potato feathery mottle virus (SPFMV) were constructed by fusing mouse myeloma (Sp2/0-Ag14) with mouse splenocytes immunized with SPFMV-LF. The McAb secreted by the two hybridomas specifically reacted with both SPFMV-LF (China strain) and SPFMV-RC (American strain) in dot-blot-ELISA. A large amount of McAb was produced with BALB/c mice. The titer of hybridoma cultured supernatant was 1:256, and that of the ascitic fluids was 1:1 x 10(4); and the immunoglobulins of McAb were IgG2a and IgG3 respectively. The detection of SPFMV-infected sweet potato plants with McAb confirmed that the McAb obtained in this test were desirable for large-scale routine surveys of SPFMV. This study on construction of hybridomas and detection of SPFMV using McAb is the first report in the world.

Effects of chronic nicotine and haloperidol administration on muscarinic receptor-mediated phosphoinositide turnover in rat brain slices

Muscarinic receptor-mediated phosphoinositide (PI) turnover in rat brain slices was assessed after chronic administration of nicotine (12 mg/kg/day) or haloperidol decanoate (1.5 mg/kg/day), either alone or in combination, for 6 weeks. Nicotine alone did not significantly alter carbachol-induced inositol monophosphate (IP1) accumulation in the frontal cortex, but did result in a significant increase in the hippocampus, and in a decrease in the striatum. Haloperidol alone attenuated carbachol-stimulated IP1 accumulation in all three brain regions. Chronic treatment with combined nicotine and haloperidol resulted in no significant change in carbachol-sensitive IP1 accumulation in either the frontal cortex or hippocampus but did result in a decrease in the striatum. The results suggest significant cross-talk between cholinergic and dopaminergic systems in affecting PI metabolism.

Activation of BPV-1 replication in vitro by the transcription factor E2

Soluble extracts from uninfected murine cells supplemented with purified viral E1 and E2 proteins support the replication of exogenously added papilloma virus DNA. The E2 transactivator stimulates the binding of the E1 replication protein to the minimal origin of replication and activates DNA replication. These results support the concept that transcription factors have a direct role in the initiation of DNA replication in eukaryotes by participating in the assembly of a complex at the origin of replication.

[Rational close planting in raising the seedlings of Panax quinguefolium linn]

It has been found that the effect of planting density is hardly noticeable for one-year-old seedlings, but very apparent for 2-year-old ones. With the increase of planting density, the leaf area gets smaller, stem higher, and root thinner and shorter. The larger the planting density. The smaller the dry weights of canopy and root and the root-canopy ratio. It is thus advocated that rational planting densities be selected according to the proper cultivation systems.

The expression of human intercellular adhesion molecule-2 is refractory to inflammatory cytokines

The beta 2-integrin CD11a/CD18 binds to the intercellular adhesion molecules (ICAM)-1 (CD54) and ICAM-2. ICAM-1 has a wide distribution, and its expression is up-regulated by various cytokines. In contrast, ICAM-2 has a more restricted distribution, and is mainly expressed on endothelial cells. In the present study we show that it is not induced by inflammatory cytokines or other treatments on any of several cells studied. Moreover, antibodies to the intercellular adhesion ligands were not able to block all CD11a/CD18-dependent adhesion, indicating the presence of additional CD11a/CD18 ligands.

[A study on the development of vertebral column in reference to the gestational ages of fetuses]

The anteroposterior radiographs and ultrasound measurements of vertebral columns ranging from 12 to 33 weeks' gestation were studied. Two kinds of regressive equations were developed: one for estimating the length of cervical, thoracic and lumbar regions of vertebral column in accordance to gestational ages, and the other for estimating the gestational ages on the basis of the length of cervical, thoracic and lumbar regions of vertebral column. The normal values with confidence interval in accordance to the length of lumbar vertebral column for estimating the gestational ages were obtained. Also presented were the adjusted values of intercept between the data of ultrasound measurement and X-ray measurement. The ossification centers of neural arch appeared first in the upper cervical vertebrae, then they extended towards the lower vertebrae. Ossification centers for the vertebral centra appeared first in the lower thoracic/upper lumbar region and then extended to the lower and upper centra, respectively. Combining the length of lumbar vertebral column with the appearance time of the ossification centers of cervical vertebral centra, sacral vertebral centra and sacral neural arch, the authors set a standard for assessing the developmental condition of 12-23 weeks' fetuses.

Feedback control of mitosis in budding yeast

We have investigated the feedback control that prevents cells with incompletely assembled spindles from leaving mitosis. We isolated budding yeast mutants sensitive to the anti-microtubule drug benomyl. Mitotic arrest-deficient (mad) mutants are the subclass of benomyl-sensitive mutants in which the completion of mitosis is not delayed in the presence of benomyl and that die as a consequence of their premature exit from mitosis. A number of properties of the mad mutants indicate that they are defective in the feedback control over the exit from mitosis: their killing by benomyl requires passage through mitosis; their benomyl sensitivity can be suppressed by an independent method for delaying the exit from mitosis; they have normal microtubules; and they have increased frequencies of chromosome loss. We cloned MAD2, which encodes a putative calcium-binding protein whose disruption is lethal. We discuss the role of feedback controls in coordinating events in the cell cycle.

Chronic haloperidol treatment attenuates receptor-mediated phosphoinositide turnover in rat brain slices

The long-term effects of haloperidol on phosphoinositide turnover in rat brain slices were investigated. Continuous treatment with haloperidol decanoate (21 mg/kg I.M. biweekly for 6 weeks) significantly attenuated carbachol- and norepinephrine (NE)-induced inositol phosphate accumulation in rat frontal cortex and hippocampus. In the striatum, the haloperidol treatment also significantly decreased carbachol-stimulated inositol phosphate level but did not significantly affect NE-sensitive phosphoinositide turnover. These effects were not observed in rats treated with a single dose of haloperidol (1.5 mg/kg). Basel levels of inositol phosphate in these 3 brain regions did not change following continuous or single haloperidol doses.

[Etiological diagnoses in 53 cases of pneumonia]

Secretion was taken from lower respiratory tract for bacterial culture using Japanese made single-sheath catheter brush (SSC) via fiberoptic bronchoscopy in 53 cases with community acquired pneumonia and 16 control cases without pulmonary infection. The results showed that bacteria were isolated in 42 out of the 53 patients, the organisms being pathogenic in 39 out of the 53 (73.5%). Among the bacteria isolated from the 42 cases, gram-negative bacilli accounted for the highest rate of 36% and pneumococcus the next of 31%. There were only 3 cases yielding contamination. It is shown that SSC technique has less chance of contamination and is convenient and practical.

v-myb and v-ets cooperate for the mitogenic stimulation of primary fibroblasts by avian E26 retrovirus

By using a series of deletion mutants, we have shown that the stimulation of fibroblast growth by E26 requires the cooperation of the two oncogenes, v-myb and v-ets, fused in the nuclear viral product. Of the two DNA-binding domains, only one must be present to promote anchorage-independent growth, whereas that of v-myb is required to allow growth in low serum medium. Furthermore, the v-ets oncogene comprises multifunctional domains.

Direct interaction between Sp1 and the BPV enhancer E2 protein mediates synergistic activation of transcription

The physical interaction of heterologous site-specific DNA-binding proteins is an important theme in eukaryotic transcriptional regulation. In this paper, we show that the cellular transcription factor Sp1 and the BPV-1 (bovine papillomavirus type 1) enhancer protein E2 activate transcription synergistically from two papilloma viral promoters and a series of synthetic promoter constructs in transient transfection experiments. Furthermore, Sp1 can target E2 to a promoter region even in the absence of a specific E2 DNA-binding motif. Biochemical experiments establish that Sp1 enhances E2 binding to its sites and that the two proteins form a specific complex. Sp1 sequesters distally bound E2 to the promoter region by formation of stable DNA loops, visualized by electron microscopy. These experiments substantiate the notion that enhancer binding proteins are targeted to promoter regions by direct interaction with proteins that bind proximal to the transcriptional start site.

The activation domain of the bovine papillomavirus E2 protein mediates association of DNA-bound dimers to form DNA loops

The E2 transactivator protein of bovine papillomavirus binds its specific DNA target sequence as a dimer. We have found that E2 dimers, preformed in solution independent of DNA, exhibit substantial cooperativity of DNA binding as detected by both nitrocellulose filter retention and footprint analysis techniques. If the binding sites are widely spaced, E2 forms stable DNA loops visible by electron microscopy. When three widely separated binding sites reside on the DNA, E2 condenses the molecule into a bow-tie structure. This implies that each E2 dimer has at least two independent surfaces for multimerization. Two naturally occurring shorter forms of the protein, E2C and E8/E2, which function in vivo as repressors of transcription, do not form such loops. Thus, the looping function of E2 maps to the 161-amino acid activation domain. These results support the looping model of transcription activation by enhancers.

Spinal evoked potential P2 wave elicited by C fiber input and depressed by analgesic factors

Spinal cord potentials were recorded from the surface of the spinal cord of rats. The effects of various treatments on a positive wave following the original P wave, which was evoked by strong electrical stimulation and named the P2 wave, were investigated. The results of this study demonstrate that capsaicin applied on to the sciatic nerve, intrathecal injection of morphine, electroacupuncture and noxious heat applied to the hindpaw contralateral to the recording side could suppress the P2 wave. These data suggest that P2 is mediated by C afferents and might be useful as a new indicator of spinal nociception.

Effects of somatotropin on milk yield and physiological responses during summer farm and hot laboratory conditions

The effects of bST on performance and physiological responses of lactating cows was studied under farm summer and laboratory heat conditions. Twelve cows, 90 to 50 d postpartum, were injected with either bST or vehicle solution for 30 d under farm summer and 10 d under either laboratory thermoneutral or heat conditions. Somatotropin increased milk yield by 6.1 (21%), 8.1 (32%), and 7.3 kg (35%) under the farm summer, laboratory thermoneutral, and heat conditions, respectively. Somatotropin also increased milk fat by 15 and 19% and dry matter intake by 16 and 18% under laboratory thermoneutral and heat conditions, respectively. Somatotropin increased the efficiency of feed conversion into milk without any significant changes in body weight and temperatures. Somatotropin reduced plasma concentrations of triiodothyronine and cortisol and had no effect on plasma prolactin and insulin concentrations. Somatotropin did not increase water intake; however, hematocrit was decreased. The results suggest that stimulatory effects of bST on milk production are still observed on heat-stressed cows without any significant indications of additional heat stress.

Rapid freezing of the mouse blastocyst: effects of cryoprotectants and of time and temperature of exposure to cryoprotectant before direct plunging into liquid nitrogen

This study investigates the effects of time and temperature of exposure to a high concentration (4.5 M) of dimethyl sulfoxide (DMSO), glycerol, 1,2-propanediol (PROH), or a mixture of DMSO and glycerol (DG) in a solution containing 0.25 M sucrose, on the survival and development of rapidly frozen mouse blastocysts. Embryos had significantly (P less than 0.01) higher rates of survival and development when exposed to cryoprotectant at 0 degree C compared with room temperature. The time of exposure to cryoprotectant at either 0 degree C or room temperature before being plunged into liquid nitrogen significantly (P less than 0.01) affected the survival and development of frozen-thawed embryos. Survival and development of blastocysts in vitro and in vivo was significantly (P less than 0.05) higher when exposed at 0 degree C for 10 min to DG, DMSO and glycerol than to PROH. It is concluded that, unlike early-cleavage stage embryos, blastocysts need to be equilibrated at a low temperature (0 degree C) with high concentrations of cryoprotectant before rapid freezing. Exposure of blastocysts to 4.5 M cryoprotectant and 0.25 M sucrose at room temperature either was toxic or else markedly reduced their viability after freezing and thawing, depending on the duration of the initial exposure.

[Survey of Bacillus thuringiensis and Bacillus sphaericus from soils of four provinces of China and their principal biological properties]

A number of isolates of Bacillus thuringiensis and Bacillus sphaericus were obtained from soils of Southwestern Area and Shaanxi Province of China. Among isolates of B. thuringiensis were under 13 sorts of serotype in total of 23 sorts of B. thuringiensis and about 20% of auto-agglutinate strains. Rules of ecologic distribution of two sorts of bacteria were analysed. Toxicities on six species of insects, morphology and crystal proteins of B. thuringiensis, as well as toxicities, morphology and crystal proteins of B. sphaericus, were investigated. 22 strains of more efficient of B. thuringiensis and 2 strains of more efficient of B. sphaericus were obtained. It was shown that B. thuringiensis is actually soil microorganism, and resource of B. thuringiensis is much fruitful in Southwestern Area of China.

[Study of dental maturity in children aged 3-16 years in Chengdu]

Dental maturity was studied in a group of 903 healthy children (boys: 465, girls: 438) born in Chengudu from 1972 through 1988. Dental maturity was estimated by the method of Demirjian and Goldstein, which is based on the development of seven left mandibular permanent teeth; teeth formation was studied. The standard and curves of dental maturity for Chengdu children (boys and girls) were constructed. At 3-5 years old, boys had their dental maturity slightly earlier than girls; there was no significant difference between boys and girls (P greater than 0.05). At the age of 7-14, girls were more advanced than boys (P less than 0.05). Developmental curves of seven left mandibular permanent teeth were plotted. The sexual difference was smaller at the crown developmental stage, and it increased during the root development. In all, girls were more advanced by 0.45 year than boys. The maximum average difference was 0.85 year for the canine. The time that each developmental stage has taken was shorter in 50% of girls as compared with that in boys, and it was longer in 28% of girls. There was no difference between boys and girls in the remaining 22% of cases.