The retinoblastoma gene product regulates Sp1-mediated transcription

We have demonstrated that the retinoblastoma gene product (Rb) can positively regulate transcription from the fourth promoter of the insulinlike growth factor II gene. Two copies of a motif (the retinoblastoma control element) similar to that found in the human c-fos, transforming growth factor beta 1, and c-myc promoters are responsible for conferring Rb regulation to the fourth promoter of the insulinlike growth factor II gene. We have shown that the transcription factor Sp1 can bind to and stimulate transcription from the retinoblastoma control element motif. Moreover, by using a GAL4-Sp1 fusion protein, we have directly demonstrated that Rb positively regulates Sp1 transcriptional activity in vivo. These results indicate that Rb can function as a positive regulator of transcription and that Sp1 is one potential target, either directly or indirectly, for transcriptional regulation by Rb.

[Chemical studies on immunologically active polysaccharides of Ganoderma lucidum(Leyss. ex Fr.) Karst]

BN3B, the polysaccharide component of the fruit of Ganoderma lucidum, has been shown to have immune activity. From BN3B four homogeneous polysaccharides were separated and purified. Chemical studies on the main components BN3B1 and BN3B3 indicated that BM3B1 contained only glucose and should be a glucan containing beta-(1----6) and (1----3)glycoside bonds and that BN3B3 was an arabinogalactan containing beta-(1----6) and (1----3)glycoside bonds.

[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.

[Description of six new species of the family Anthomyiidae from Mountain Emei]

1. Eutrichota (Parapegomyia) tuberifolia Deng, Fan et Li, sp. nov. Male: Body length 6mm. The new species is related to Eutrichota (Parapegomyia) socculata Zett., 1938, both with the posterior lobe of pregonites well extended. But the former differs from the latter by the expanded fore part of posterior twig of pregonite and a deep concaving on anterior part of postgonite beyond the setuta. Holotype male, paratypes 2 male male (kept in Department of Parasitology, West China University of Medical Sciences), Leidongping, Mt. Emei, Sichuan, China, July 1983, coll Deng Anxiao. 2. Pegohylemyia apiciquadrata Deng, Fan et Li, sp. nov. male: Body length 6.5mm. The new species resembles Pegohylemyia spinisternata Suwa, 1974 and is characterized by a quadrately apex of cerci and an eagle-beaked apex of postgonites. Holotype male (kgpt in Shanghai Institute of Entomology), paratypes 4 male male (kept in Department of Parasitology, West China University of Medical Sciences) Jinding Mt. Emei, Sichuan, China, July 1984, coll. Deng Anxiao. 3. Pegohylemyia macrospinigera Deng, Fan et Li, sp. nov. male: Body length 6mm. The new species is similar to Pegohylemyia zhuoniensis Jin, 1983 in shape of the cerci and surstyli, having a round but not pointed apex of postgonite and a rank of much strong bristles on the inner side of 5th sternite. Holotype male, paratypes 4 male male (as is stated above No. 2), Huayanding, Mt. Emei, Sichuan, China, July 1984, coll. Deng Anxiao. 4. Pegohylemyia Pardocephalla Deng, Fan et Li, sp. nov. male: Body length 6mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Plant regeneration from cotyledon protoplasts of Xinjiang muskmelon

Cotyledon protoplasts were isolated from seedlings of Xinjiang muskelon (Cucumis melo var.saccharinus) grown under sterile conditions and cultured in modified Miller medium. High frequency division of the protoplast-derived cells was observed. Agarose bead culture with B6S3 tobacco crown gall nurse cells was found most suitable for the cotyledon protoplasts when compared with other culture methods. Intact plants were regenerated from the protocalli by a two-step culture procedure with liquid and then solid media.

[An epidemiological survey of gallstones with gray-scale ultrasound]

Gray-scale real-time ultrasound has been employed to investigate gallstone with a positive result of 553 cases out of 15,856 healthy subjects in city and countryside, the incidence being 34.88%. The feature of incidence is as follows: 1. The incidence of the simple gallbladder stone is more common than that of the other sites (male is about 81.15%, female is about 87.29%); 2. The incidence of gallstones of city residents is higher than that of the country people with significant difference statistically (P less than 0.01); 3. The incidence of gallstone in female city residents is higher than male, about 2.5:1, which shows significant difference. (P less than 0.01); 4. The incidence of gallstones in female city residents is higher than in countryside (P less than 0.01); 5. There is no significant difference in the incidence of gallstone between male and female in the countryside (P greater than 0.05); 6. There is no significant difference in the incidence of gallstones between city male and the male in the countryside (P greater than 0.05); 7. Either in the city or in the countryside, it has been shown that there is a tendency of increasing incidence of gallstone with age in both sexes (P less than 0.01). The relationship between the gallstone and the clinical symptoms has been discussed in this paper.

[A short revision of the species group Pegomya acklandi, with description of a new species (Anthomyiidae, Diptera)]

A key to 1 Japanese and 18 Chinese species of the Pegomya acklandi group, including 1 new species, is given below: 1(4) Apical border of the lateral lobe of 5th sternite with an angular notch. 2(3) Hairs on the basal part of surstylus rather thick and numerous; inner side of the twig of surstylus with a tubercle; apex of postgonite hook-like. ... Pegomya densipilosa Li et Deng, 1984. 3(2) Basal part of surstylus with sparse hairs; postgonite bluntly rounded at the apex ... P. rhagolobos Li et Deng, 1984. 4(1) No angular notch on the apical border of the lateral lobe of 5th sternite. 5(10) Aedeagus of fork type. 6(9) Lateral lobe of the 5th sternite with an arch of long setae. 7(8) Arch of long setae of the lateral lobe of 5th sternite in 2 rows and the apex extremely expanded; acrophallus with a hook bent to the paraphallus at the distal end; A3 twice as long as its width ... P. semiannula Li et Deng, 1984. 8(7) Lateral lobe of 5th sternite cone-shaped; acrophallus pointed apically and slightly curved; A3 as long as its width ... P. laterisetiata Deng et Li, 1988. 9(6) Setae on the lateral lobe of 5th sternite rather sparse and short; a strong seta behind the cerca; acrophallus with a small hook at the distal end; A3 as long as its width ... P. unimediseta Deng et Li, 1988.(ABSTRACT TRUNCATED AT 250 WORDS)

[The measurement of radial bone mineral content in children]

The bone mineral contents of radius of 255 boys and 243 girls (7 to 16 year old of the Han nationality, living in Chengdu) were measured with Bone Mineral Analyzer (Type:SPA-I). The standard values of g/cm was made. There was a positive correlation between the value in boys or girls and chronological age, height or weight. The coefficients were respectively 0.83, 0.77, 0.64 in boys and 0.82, 0.82, 0.82 in girls (P less than 0.005). At the age of 13 (in boys or in girls) the value of the g/cm was the highest.

[Comparative clinical study of rheumatoid arthritis treated by triptolide and an ethyl acetate extract of Tripterygium wilfordii]

It was satisfactory using the ethyl acetate extract of Tripterygium wilfordii (TW) to treat rheumatoid arthritis (RA). The results showed that the ethyl acetate extract of TW was the effective component part of TW. Although the therapeutic effect of 15 cases with RA cured by triptolide was as effective as the ethyl acetate extract of TW, triptolide could impair some patients' hearts. This suggested that triptolide was one of the main effective elements of TW, but it was also one of the main toxic elements. Clinical research indicated that: (1) the effect of TW in treating RA was the synergistic action of elements with triptolide as the main; (2) triptolide may act as a major standard of controlling the quality of the preparation of TW and assure clinical use safely.

[Effect of a mixture of Acanthopanax senticosus and Elsholtzia splendens on serum-lipids in patients with hyperlipemia]

The serum-lipids were determined in 31 hyperlipemia patients before and after treated with the mixture of Acanthopanax senticosus and Elscholtzia splendens. While the mean value of serum beta-lipoprotein decreased from 902 +/- 228 mg/dl to 608 +/- 189 mg/dl (P less than 0.001), the mean value of HDL-C increased from 52.6 +/- 12.5 mg/dl to 61.2 +/- 15.4 mg/dl (P less than 0.001). Thus the ratios of HDL-C to total cholesterol (HDL-C/TC) and to LDL-C (HDL-C/LDL-C) increased significantly, the arteriosclerosis index (AI) decreased significantly. The results indicate that the mixture of Acanthopanax senticosus and Elsholtzia splendens could improve the lipid-metabolism in hyperlipemia patients so that it might play a good role in preventing or alleviating arteriosclerosis.

Intravenous tryptophan tolerance test for liver function

An intravenous tryptophan tolerance test (ITrpTT) was designed for liver function since 95% Trp is metabolized by the liver. After an intravenous loading dose of 4 mg/kg body weight, serum levels of both free (F) and total (T) Trp were determined at 45 and 60 minutes. In normal controls and nonhepatic-disease patients, F45 (60) and T45 (60) did not exceed 7 mumol/L and 80 mumol/L, respectively, and F/T ratio not greater than 0.14. These were set up as cutoffs of upper normal limits. The test was abnormal in 87.5% of chronic persistent hepatitis (CPH) characterized by elevation of T45 (60), 100% of chronic active hepatitis (CAH) by elevation of F45 (60) and/or T45 (60), and 100% of hepatic cirrhosis by increase in F45 (60) and F/T ratio but not in T45 (60). The test seems to be more sensitive than the conventional tests for liver function. However, one should be cautious in interpretation of the test as there are some factors which might influence the Trp metabolism like exercise, alcoholism, corticosteroids and enzyme-inducers. It merits as an indication of liver dysfunction only when these factors are considered and excluded.

Maximum survival of frozen goat embryos is attained at the expanded, hatching and hatched blastocyst stages of development

Embryos were collected 5, 6 and 7 days after ovulation to determine their optimum stage of development for cryopreservation. The embryos were frozen using either glycerol or dimethyl sulfoxide (DMSO) as cryoprotectant, and then thawed and cultured to determine their viability. The rate of survival increased as the stage of development of the embryos increased. All hatched blastocysts survived freezing regardless of which cryoprotectant was used, whereas none of the 22 morulae frozen with DMSO survived, and only 12 of the 63 morulae frozen with glycerol survived. At the early blastocyst stage there was a significantly different result between freezing procedures (P less than 0.05) with greater survival rates obtained using DMSO rather than glycerol. The viability of goat embryos obtained at the early to hatched blastocyst stages, when collected 7 days after ovulation, was assessed by transferring half the embryos singly to recipients and freezing the remainder before transfer. When pregnancy was tested at the 7th week of gestation, the survival rate of fresh embryos was 67/111 (60%) compared with 64/109 (59%) for frozen-thawed embryos.

[Observation on the annual and seasonal changes of anatomic characteristics of the main root of Panax ginseng C.A. Meyer]

Annual dynamic of the main root of Panax ginseng shows that the cross-section of various tissues increases gradually with age, but the ratio of phloemxylem in cross-section decreases. Seasonal dynamic shows that cells of phellogen and cambium divide actively in June-July and gets retarded in August. Ecological conditions can influence annual and seasonal dynamics of the structure of the main root.

[Study of the relation of the typology of nephrotic syndrome and red cell C3b receptor, T cell function]

This paper reports the determined results of rosette rates of red cell C3b receptor and active rosette (Ea) rates of T lymphocyte in 39 cases of nephrotic syndrome. Typology of nephrotic syndrome according to TCM differentiation symptoms, all the 39 cases were divided into three types: (1) 13 cases of deficiency of Qi of the Spleen with stagnancy of dampness; (2) 9 cases of deficiency of Yang of the Spleen and Kidney; (3) 17 cases of deficiency of Yin of the Liver and Kidney. The results showed that the red cell C3b receptor rosette rate and Ea rosette rate in 39 cases of nephrotic syndrome were significantly lower than those in the control. The difference between the two groups was very obvious (P less than 0.001) among the three types. The rosette rates of both in the deficiency of Qi of the Spleen and deficiency of Yang of the Spleen and Kidney were markedly decreased than those in the control (P less than 0.001). Whereas, the red cell C3b receptor rosette rate was lower than that in the control (P less than 0.01), and T cell Ea rosette rate showed no statistical difference (P greater than 0.05) in the deficiency of Yin of the Liver and Kidney. There was a close relationship between the immune dysfunction of red cell and the pathogenesis in nephrotic syndrome. There was markedly relationship between the pathogenesis of deficiency of Yang of the Spleen and Kidney and deficiency of Qi of Spleen with stagnancy of dampness and T cell immune dysfunction. While the Ea level in deficiency of Yin of the Liver and Kidney was closely correlated with the control. Probably this type was nephrotic nephrosis which had been treated with TCM-WM.

Specific recognition nucleotides and their DNA context determine the affinity of E2 protein for 17 binding sites in the BPV-1 genome

The DNA context of nucleotides that a protein recognizes can influence the strength of the protein-DNA interaction. Moreover, in prokaryotes, understanding the quantitative differences in binding affinities that result in part from the DNA context is often important in describing regulatory mechanisms. Nevertheless, these issues have not been a major focus yet for the investigation of protein-DNA interactions in eukaryotes. In this study, we explored the binding specificity and the range of affinities that the BPV-1 E2 transcriptional activator has for DNA. Because E2 binding sites are positioned near several different BPV-1 promoters, such quantitative information may be important to understand transcriptional regulatory mechanisms in BPV-1. Gel retardation assays and DNA footprinting were used to quantitate the affinities of the E2 binding sites in the viral genome. In the process, five sites were discovered, which, on the basis of sequence, had not been predicted previously to interact with the E2 protein. Equilibrium and kinetic studies show that the range of E2 affinities of the 17 sites varied over 300-fold. The sequence elements responsible for E2 recognition of DNA were determined by missing contact analysis of several sites and a point mutation analysis of one site. The results presented show that the affinity of an E2 binding site is to a large extent determined by the availability of specific contacts, but the data also strongly suggest that DNA structure plays an important role.

Search for satellite reflections and low-temperature study of the 1223 and 2212 Tl–Ba–Ca–Cu–O superconductors

The structures of the 1223 and 2212 phases of the T1-Ba-Ca-Cu-O system have been determined at 125 K. No satellite reflections were observed in extensive searches at both room and low temperature. The temperature dependence of the thermal parameters of the thallium atoms confirms the presence of a static disorder beyond that already incorporated in the refinements.

Pre-mRNA splicing mutants of Schizosaccharomyces pombe

A collection of temperature sensitive (ts-) mutants was prepared by chemical mutagenesis of a wild type Schizosaccharomyces pombe strain. To screen the ts- mutants for pre-mRNA splicing defects, an oligodeoxynucleotide that recognizes one of the introns of the beta-tubulin pre-mRNA was used as a probe in a Northern blot assay to detect accumulation of intron sequences. This screening procedure identified three pre-mRNA splicing mutants from 100 ts- strains. The three mutants are defective in an early step of the pre-mRNA splicing reaction; none accumulate intermediates. The precursors that accumulate at 37 degrees C are polyadenylated. Analysis of the splicing of another pre-mRNA showed that the mutations are not specific for beta-tubulin. The total RNA pattern in the three splicing mutants appears to be normal. In addition, the amounts of the spliceosomal snRNAs are not drastically changed compared to the wild type and splicing of pre-tRNAs is not blocked. Genetic analyses demonstrate that all three splicing mutations are tightly linked to the ts- growth defects and are recessive. Crosses among the mutants place them in three complementation groups. The mutants have been named prp1, prp2 and prp3.