[Attachment of bacillus Calmette-Guerin to bladder cancer cells and the expression of interleukin-6 biological activity]

In order to elucidate the mechanisms of antitumor efforts of bacillus Calmette-Guerin (BCG), the effects of attachment of BCG to bladder carcinoma cell line EJ and the role of fibronectin in the in vitro experiment were studied. At the same time, the IL-6 biological activity in the medium of EJ cells was determined and the IL-6 biological activity in presence of BCG compared. The results indicated that BCG attached strongly to EJ cells, and the maximal attachment to the cells with BCG occurred 48 hours after culture. Fibronectin could significantly increase the attachment and not acclerate the proliferation of EJ cells. In the presence of fibronectin-conditioned medium, the maximal percentage of the tumor cells with attached BCG was 74.22%. Under this condition of experiment, there was IL-6 biological activity in the medium of EJ cells. The treatment of EJ cells with BCG did not regulate the expression of IL-6.

Effects of liuwei dihuang wan [symbol: see text:bd and some other TCM drugs on bone biomechanics and serum 25 (OH)D3 content in rats

After a relatively long-term injection of hydrocortisone into rats, the strength of bone (anti-stress capacity) reduced evidently, while the rigidity (anti-deformity capacity) increased markedly (ie, bone fragility elevated). At the same time, the content of serum 25(OH)D3 decreased remarkably. After oral administration of Liuwei Dihuang Wan ([see symbol: see text]), anti-stress capability of bone increased evidently and its anti-deformity capability returned to normal; however, there was no elevation of serum 25(OH)D3 content. The effect of Longmu Zhuanggu Chongji ([see symbol: see text]) or Jisheng Shenqi Wan (see symbol: see text]) was lower than that of Liuwei Dihuang Wan. The experiments suggests that Liuwei Dihuang Wan is beneficial to preventing and curing osteoporosis, but no correlation between its mechanism and the metabolism of 25(OH)D3 was demonstrated.

[A new species of Thermoplasma]

An extremely thermoacidophilic strain, ES-23, was isolated from a self-heating coal spoil pile, Sichuan, China. The new isolate grows between 50 and 75 degrees C with optimum 70 degrees C and pH 1.0-5.0 with optimum 2.0. Strain ES-23 is aerobic and facultative autotrophic depending both heterotrophically on organic compounds and autotrophically on elemental sulfur as energy source and CO2 as carbon source. G-, spherical or oval with 0.9-1.5 microns in diameter. The autotrophic growth showed peri pilus-like structure. Cells Lack a rigid cell wall and surrounded only by a single triple layed membrane containing ether lipids. GC content of DNA is 38 mol%(Tm). It has been determined as a new species of Thermoplasma genus and named Thermoplasma thiooxidans sp. nov.

Close reciprocal regulation of beta 1- and beta 2-adrenergic receptors by dexamethasone in C6 glioma cells: effects on catecholamine responsiveness

We studied the regulation of beta-adrenergic receptor (AR) subtypes co-existing in rat C6 glioma cells to clarify the importance of subtype ratio in responses to catecholamines. Radioligand binding studies with [125I]-cyanopindolol showed that beta 1- and beta 2-ARs co-existed in this cell line in approximately an 80:20 ratio. Norepinephrine (NE) and epinephrine (EPI) were equally potent in increasing cAMP accumulation, consistent with a primarily beta 1-response, although both beta 1- and beta 2-components of the response could be isolated using selective agonists (NE and zinterol), and antagonists (CGP 20712A and ICI 118,551). Little or no evidence of beta 3-ARs could be found in this cell line. Treatment of cells with 500 nM dexamethasone (DEX) for 48 hr increased the proportion of beta 2-ARs (20 to 60%). However, a reciprocal decrease in beta 1-ARs resulted in no change in total beta-ARs. Studies on the time-(12 to 72 hr) and concentration- (5 nM to 5000 nM) dependence of DEX treatment showed that increases in beta 2-ARs were closely linked to decreases in beta 1-ARs with little or no change in total receptor density observed at any time or in any concentration studied. Treatment with DEX also increased beta 2- and decreased beta 1-mediated cAMP responses, but did not alter the response to the nonselective agonist, isoproterenol. Northern blot analysis showed a 2- to 3-fold increase in beta 2-AR mRNA, but no change in beta 1-AR mRNA, after exposure to 50 or 500 nM DEX for 48 hr. Surprisingly, after DEX treatment, NE and EPI were still equally potent in activating cAMP accumulation, although responses to the beta 2-selective agonist, zinterol, were increased. These studies show a close reciprocal regulation by DEX of the relative proportions of beta 1- and beta 2-AR subtypes in C6 cells. The functional significance of the changing subtype ratios does not appear to be related to catecholamine responsiveness.

Transgenic plants of turfgrass (Agrostis palustris Huds.) from microprojectile bombardment of embryogenic callus

Transgenic creeping bentgrass (Agrostis palustris Huds., cv. Pencross; Poaceae) plants have been obtained by microprojectile bombardment of and regeneration from embryogenic calli with a vector designed to deliver the β-glucuronidase (GUS) gene under the control of rice actin 1 5' regulatory sequences. Southern analysis of polymerase chain reaction (PCR)-amplified and restriction-digested genomic DNA of four transgenic plants regenerated from these cultures showed the unscrambled integration of the gus fragment. Northern blot analysis confirmed the expression of gus mRNA in one of the transgenic plants. Western blot analysis revealed a high level of accumulation of gus protein. Histochemical assays showed enzymatic activity of β-glucuronidase in all parts of the transgenic turfgrass plant. The order of gus expression level in different tissues of the transgenic plant is as follows: stem node > first young leaf > root tip > second / third / fourth young leaf > stem internode > root hair-zone.

Selective expression of mitogen-inducible cyclooxygenase in macrophages stimulated with lipopolysaccharide

Two forms of cyclooxygenase are known to be present in eukaryotic organisms: a cyclooxygenase (COX-1) first purified from ram seminal vesicles encoded by a 2.8-kilobase mRNA, and a newly discovered mitogen-inducible cyclooxygenase (COX-2) encoded by a 4-kilobase mRNA. Expression of these two forms of the enzyme in rat alveolar macrophages stimulated with lipopolysaccharide was investigated by 1) determining the activity of newly synthesized enzyme after inactivating the endogenous enzyme with aspirin; 2) comparing levels of newly synthesized enzyme proteins in cells treated with or without lipopolysaccharide; and 3) assessing the expression of the mRNAs encoding COX-1 and COX-2. Levels of enzyme proteins were assessed by Western blot analysis and immunoprecipitation of 35S-labeled enzyme using two different antibodies, one specific for COX-2 and the other recognizing both forms of the enzyme but preferentially recognizing COX-1. We report here that the enhanced cyclooxygenase activity induced by the bacterial lipopolysaccharide in rat alveolar macrophages is caused by selective expression of the COX-2. Expression of COX-2 in macrophages stimulated by lipopolysaccharide was completely inhibited by dexamethasone, whereas COX-1 was unaffected. In resting unstimulated macrophages, only COX-1 but not COX-2 was detected. Levels of mRNA for the COX-2 in macrophages were increased, but those of the COX-1 were not affected by lipopolysaccharide as assessed by reverse transcription coupled with polymerase chain reaction. These results indicate that increased synthesis of prostaglandins and thromboxanes in lipopolysaccharide-stimulated macrophages results from selective expression of COX-2.

In-vitro morphogenesis of corn (Zea mays L.) : I. Differentiation of multiple shoot clumps and somatic embryos from shoot tips

In-vitro methods have been developed to regenerate clumps of multiple shoots and somatic embryos at high frequency from shoot tips of aseptically-grown seedlings as well as from shoot apices of precociously-germinated immature zygotic embryos of corn (Zea mays L.). About 500 shoots were produced from a shoot tip after eight weeks of culture (primary culture and one subculture of four weeks) in darkness on Murashige and Skoog basal medium (MS) supplemented with 500 mg/L casein hydrolysate (CH) and 9 μM N(6)-benzyladenine (BA). In this medium, shoots formed in shoot tips as tightly packed "multiple shoot clumps" (MSC), which were composed of some axillary shoots and many adventitious shoots. When the shoot tips were cultured on MS medium containing 500 mg/L CH, 9 μM BA and 2.25 μM 2,4-dichlorophenoxyacetic acid (2,4-D), most of the shoots in the clumps were adventitious in origin. Similar shoot tips cultured on MS medium containing 500 mg/L CH, 4.5 μM BA and 2.25 μM 2,4-D regenerated many somatic embryos within eight weeks of culture. Somatic embryos were produced either directly from the shoot apical meristems or from calli derived from the shoots apices. Both the MSC and the embryos produced normal shoots on MS medium containing 2.25 μM BA and 1.8 μM indole-3-butyric acid (IBA). These shoots were rooted on MS medium containing 3.6 μM IBA, and fertile corn plants were grown in the greenhouse. The sweet-corn genotype, Honey N Pearl, was used for the experiments described above, but shoot-tip cultures from all of 19 other corn genotypes tested also formed MSC on MS medium containing 500 mg/L CH and 9 μM BA.

In-vitro morphogenesis of corn (Zea mays L.) : II. Differentiation of ear and tassel clusters from cultured shoot apices and immature inflorescences

The objective of this research was to study the in-vitro morphogenetic pattern of corn (Zea mays L.) shoot tips excised from aseptically-grown seedlings, and of expiants of axillary shoot buds, immature tassels and ears (staminate and pistillate inflorescences) obtained from greenhouse-grown corn plants. The seedling shoot tips and immature ears first regenerated clumps of multiple shoots within four weeks of culture on Murashige and Skoog (MS) basal medium supplemented with 500 mg/L casein hydrolysate (CH) and 9.0 μM N(6)-benzyladenine (BA). Multiple shoot clumps were also differentiated from spikelets of immature tassels cultured on MS medium containing 500 mg/L CH, 4.5 μM BA and 0.45 μM 2,4-dichlorophenoxy acetic acid (2,4-D). All these multiple shoot clumps in turn differentiated clusters of ears after further four subcultures at four-week intervals under light on MS medium supplemented with 500 mg/L CH and 2.25, 4.5, 9.0 or 18 μM BA. Axillary shoot buds readily differentiated clusters of ears within four weeks of the initial culture on these media. Secondary and tertiary ear clusters were initiated following subculture of primary ears on MS medium containing 500 mg/L CH and 4.5 or 9.0 μM BA. Most of the ear primordia developed into ears with well-developed ovaries and styles on subculture on MS medium containing 500 mg/L CH and 1.0 μM BA. Corn kernels were obtained after pollination of in-vitro-formed ears with pollens collected from greenhouse-grown corn. These kernels germinated in vitro and developed into mature corn plants in the greenhouse. Clusters of tassels were also differentiated in darkness from the multiple shoot clumps after six months successive subcultures but the spikelet primordia of tassels failed to develop fully under the in-vitro conditions tested. Somatic embryos arose directly from spikelet primordia of young tassels or ears on MS medium containing 500 mg/L CH and 4.5 μM 2,4-D, or indirectly from calli derived from spikelets of young tassels and ears on MS medium containing 500 mg/L CH and 9.0 μM 2.4-D.

Plant regeneration via somatic embryogenesis in creeping bentgrass (Agrostis palustris Huds.)

We have established a high-frequency plant regeneration system via somatic embryogenesis from mature seeds of creeping bentgrass (Agrostis palustris Huds). The effects of 2,4-dichlorophenoxyacetic acid (2,4-D), 3.6-dichloroo-anisic acid (dicamba) and 6-benzyladenine (BA) on callus formation and embryogenesis were evaluated. Callus produced on the Murashige and Skoog (MS) (1962) medium containing 2,4-D had low embryogenic potency. In the presence of 30 μM dicamba, addition of 2.25 to 9 μM BA significantly enhanced embryogenic callus formation over dicamba alone. Optimum frequency of somatic embryogenesis was achieved on MS basal medium containing 30 μM dicamba and 2.25 μM BA. Over 80% of somatic embryos germinated and formed plantlets on half-strength MS basal medium. These plantlets grew normally in the greenhouse.

Incorporation of [C]Glucose into Cell Wall Polysaccharides of Cotton Roots: Effects of NaCl and CaCl(2)

Cotton (Gossypium hirsutum L. cv Acala SJ-2) seedlings were grown in nutrient solutions with four combinations of NaCl (0.1 and 150 millimolar) and CaCl(2) (1 and 10 millimolar) for 7 days, and then exposed to [(14)C]glucose for 5 hours. Uptake and incorporation of [(14)C]glucose into various cell wall fractions of the root tips were determined. At 1 millimolar Ca(2+), treatment with 150 millimolar NaCl slightly stimulated uptake but considerably inhibited glucose incorporation into noncellulosic and cellulosic polysaccharides. Supplemental Ca(2+) did not affect incorporation of glucose into the noncellulosic fraction (regardless of NaCl treatment) but completely alleviated the inhibitory effect of NaCl on glucose incorporation into cellulose. We suggest that high Na(+) concentrations reduce synthesis of cellulose in cotton roots via disturbance of plasma membrane integrity and that supplemental Ca(2+) counteracts this effect. The effects on cellulose biosynthesis are proposed to be related to Ca(2+) displacement from the plasma membrane.

Study of lung flukes from Philippines: --a preliminary report

In this paper taxonomic study on paragonimus including their metacercariae obtained from the crabs collected from Sorsogon, Luzon, Philippines and adult worms and ova obtained through animal feeding, with light microscopy and scanning electron microscopy revealed that there may exist two or more species of lung flukes in Philippines. The occurrence of Semisulcospira libertina in addition to Antemelania dactylus (Lea) as an additional snail host is mentioned for the first time. The chromosome Karyotyping of the adult worms revealed that they belong to the diploid pattern. Electronic scanning showed that the cuticular spines of the Paragonimus from Sorsogon look like "pineapple ears" both in distribution and in appearance, a new finding that has not been recorded before. In the lungs of a white rat killed 290 days after infection, two adult worms were obtained within the solitary cyst. These 2 adult worms measured 4.5 x 2.5 mm and 4.5 x 3.0 mm respectively. Their unusually small size and somewhat round shape suggest that they may be of a different species from those hitherto reported in the Philippines. Clearcut evidence is presented for the first time, demonstrating the occurrence of the phenomenon of cross fertilization (allogamy) of lung flukes.