Authentic temperature-regulation of a heat shock gene inserted into yeast on a high copy number vector. Influences of overexpression of HSP90 protein on high temperature growth and thermotolerance

Heat shock protein HSP90 is relatively abundant in eukaryotic cells even in the absence of heat shock. Its precise function is still unclear, although it is apparently required in higher levels for growth at high temperatures. In this study Saccharomyces cerevisiae transformants were constructed with 50-150 copies of the homologous heat-inducible gene for HSP90 (HSP82) present on a high copy number episomal vector. These transformants were then used to demonstrate: (i) that this heat shock gene displays essentially normal regulation when present in yeast at high copy numbers; (ii) that yeast is an expression host suitable for the high level synthesis of HSP90; and (iii) that increasing normal cellular levels of HSP90 affects a number of physiological properties. The HSP82 gene is normally single-copy in the haploid yeast genome, yet even at 50 to 150 copies per cell it displayed almost normal basal and heat shock-induced levels of expression. Proper regulation of the heat shock element sequence controlling HSP82 is therefore not lost at high gene copy levels. In unstressed cultures in exponential growth at 25 degrees C the low basal expression of the multiple HSP82 gene copies caused a 3 to 7-fold HSP90 overproduction, but HSP90 levels increased 10-fold to 30-40% of total cell protein following temperature upshift to 39 degrees C for 75 min. Heat induction of the chromosomal genes for other heat shock proteins in the same cells was not suppressed relative to cells which were isogenic but for the possession of just a single HSP82 gene, this constituting further evidence that yeast can authentically regulate a large number of heat shock genes. HSP90 overproduction was not protective against heat killing, causing strain-dependent reductions in growth at 37.5 degrees C and in thermotolerance.

Glycosphingolipids of rabbit endometrium and their changes during pregnancy

The glycolipids of nonpregnant and pregnant rabbit endometrium were characterized using a combination of biochemical and immunochemical techniques. Quantitative analyses indicated a 70% decline in acidic glycolipid (ganglioside) content during early pregnancy (day 6), and a 2.5-fold increase in neutral glycolipid content during later pregnancy (day 26). The major gangliosides of rabbit endometrium were identified by thin-layer chromatography as GM3 and GD3, with minor amounts of GM1, GD1a and GT1b. The major neutral glycolipids were identified similarly as globo-series structures Gb3 and Gb4. Monoclonal antibodies (mAbs) directed to glycolipid antigens permitted the detection of additional glycolipid species, including sialylated, sulfated and fucosylated lacto-series structures. Difucosyl Ley structure (defined by mAb AH-6) and sulfated-galactosyl structure (defined by mAb VESP 6.2) were identified by indirect immunofluorescence along the luminal surface of the endometrium during the implantation period. Rapid changes in the glycolipid composition of endometrial cells during early pregnancy may facilitate embryo adhesion and trophectoderm outgrowth during implantation.

[Anti-inflammatory effect of differently processed rhizoma Typhon] off

Rat was employed to study the anti-inflammatory effect of Rhizoma Typhon processed by different methods. The result showed that processed and raw Rhizoma Typhon had similar action. With the new processing method similar anti-inflammatory effect was obtained compared with the old processing method.

Immunohistochemical identification of cytotoxic lymphocytes using human perforin monoclonal antibody

Perforin is a potent cytolytic pore-forming protein expressed in cytoplasmic granules of cytotoxic T lymphocytes and natural killer cells. A new monoclonal antibody raised against human perforin was used to detect both in vitro and in vivo perforin expression in cytotoxic cells. Immunohistochemical analysis of human peripheral blood mononuclear cells cultured in recombinant interleukin-2 (rIL-2) showed strong granular cytoplasmic staining of the IL-2 activated cytotoxic cells. Fresh-frozen tissue sections from patients with heart allograft rejection were also stained. Strong granular cytoplasmic staining of the mononuclear inflammatory infiltrate characteristic for perforin in cardiac allograft rejection was observed. The detection and quantitative analysis of perforin-associated cytotoxic cells by the human anti-perforin monoclonal antibody will help to evaluate the significance of these functionally distinct cytotoxic cells in human tissue.

Problems associated with the measurement of mean circulatory filling pressure by the atrial balloon technique in anaesthetized rats

To examine the existence of pressure equilibrium between tributary veins and the central vena cava during the mean circulatory filling pressure manoeuvre, pressures in the hepatic portal vein, renal vein, and inferior vena cava were determined at 4-s intervals over a 20-s period of circulatory arrest induced by inflating a right atrial balloon in normal blood volume, 10% volume depletion, and 10% volume expansion states in urethane-anaesthetized rats. Portal vein pressure determined 8 s after arrest during volume depletion and expansion was significantly higher than vena caval pressure (6.2 ± 0.8 vs. 3.4 ± 0.2 and 7.7 ± 0.5 vs. 6.2 ± 0.4 mmHg (1 mmHg = 133.32 Pa), respectively; p < 0.01): this pressure disequilibrium continued for 16 s during volume expansion and for the entire 20 s during volume depletion. Renal vein pressure was equal to vena caval pressure during this manoeuvre. Portal vein pressure at normal blood volume was not significantly different from vena caval pressure following circulatory arrest (4.6 ± 0.3 vs. 3.8 ± 0.4 mmHg, respectively). Following ganglionic blockade, portal vein pressure was still significantly higher than vena caval pressure for 12 s during volume alterations. At the 8th s of the arrest the portal pressure determined in volume depletion was 3.6 ± 0.3 mmHg and the inferior vena caval pressure was 2.6 ± 0.4 mmHg (p < 0.05). Under the volume expansion condition, the respective values were 6.5 ± 0.3 and 5.3 ± 0.4 mmHg (p < 0.05). We conclude that, under conditions of blood volume alterations, there is no pressure equilibrium between the portal vein and the inferior vena cava when mean circulatory filling pressure is measured by this technique; a transhepatic barrier independent of reflex control during the measurement of mean circulatory filling pressure appears to play a role in obstructing the establishment of pressure equilibrium within the venous system.Key words: mean circulatory filling pressure, vascular capacitance, hepatic portal vein pressure, unstressed volume.

MRI-T2 values in the differentiation of recurrence and fibrosis after radiation of nasopharyngeal carcinoma

The possibility of T2 values in the differentiation of local recurrence and irradiation fibrosis was studied prospectively in 36 patients with nasopharyngeal carcinoma (NPC) after radiotherapy. All the patients had a soft-tissue mass in the nasopharynx demonstrated by CT. Fourteen patients had tumor recurrence, 20 radiation fibrosis, 1 postradiation edema, and 1 inflammatory change. The control group consisted of 8 patients with untreated NPC. It was found that T2 was longer in patients with tumor than in patients with radiation fibrosis. We conclude that MRI may be used as a noninvasive method for differentiating radiation fibrosis from local recurrent NPC, but the prolonged T2 value of tumor is not specific and may be seen in radiation edema and infection.

Alteration of the binding specificity of cellular retinol-binding protein II by site-directed mutagenesis

Rat cellular retinol-binding protein II (CRBP II) is an abundant 134-residue intestinal protein that binds all-trans-retinol and all-trans-retinal. It belongs to a family of homologous, 15-kDa cytoplasmic proteins that bind hydrophobic ligands in a noncovalent fashion. These binding proteins include a number of proteins that bind long chain fatty acids. X-ray analyses of the structure of two family members, rat intestinal fatty acid-binding protein and bovine myelin P2 protein, indicate that they have a high degree of conformational similarity and that the carboxylate group of their bound fatty acid interacts with a delta-guanidium group of at least 1 of 2 "buried" arginine residues. These 2 Arg residues are conserved in other family members that bind long chain fatty acids and in cellular retinoic acid-binding protein, but are replaced by Gln109 and Gln129 in CRBP II. We have genetically engineered two amino acid substitutions in CRBP II: 1) Gln109 to Arg and 2) Gln129 to Arg. The purified Escherichia coli-derived CRBP II mutant proteins were analyzed by fluorescence and nuclear magnetic resonance spectroscopy. Both mutants exhibit markedly decreased binding of all-trans-retinol and all-trans-retinaldehyde, but no increased binding of all-trans-retinoic acid. Arg substitution for Gln109 but not for Gln129 produces a dramatic increase in palmitate binding activity. Analysis of the endogenous fatty acids associated with the purified E. coli-derived proteins revealed that E. coli-derived intestinal fatty acid binding protein and the Arg109 CRBP II mutant are complexed with endogenous fatty acids in a qualitatively and quantitatively similar manner. These results provide evidence that this internal Arg may play an important role in the binding of long chain fatty acids by members of this protein family.

[Hypocrellin A induced photodamage to the fluidity of human erythrocyte membranes and membranes of some phospholipid liposomes]

In this paper, the photodamage of Hypocrellin A to the fluidity of human erythrocyte membranes and some kinds of membranes of phospholipid liposomes was investigated by measuring the changes in fluorescence polarization of the membranes. The results showed that the photosensitization effect of HA caused the decrease of membrane fluidity of the phospholipid (DPPC, DPPC/DPPE, phospholipid of erythrocyte membranes) liposomes. The DPPC and DPPC/DPPE liposomes were more sensitive to the damage than the phospholipid liposomes of erythrocyte membranes. To human erythrocyte membranes, the photodamage effect of HA caused its fluidity first increased and then, with the increment of illumination time, decreased. To spectrin-depleted and trypsin-treated erythrocyte membranes, this kind of change in fluidity was inhibited. All of the results indicated that phospholipids and proteins play different roles in the photodamage of HA to the fluidity of membranes. Membrane proteins, especially spectrin, were the key factor involved in the changes of the fluidity.

Impaired insulin secretion of aging: role of renal failure and hyperparathyroidism

Available data indicate that insulin secretion is impaired with aging. Almost all the studies that examined insulin secretion by old animals did not take into consideration the state of renal function or the blood levels of parathyroid hormone (PTH). Old animals may have chronic renal failure (CRF) and secondary hyperparathyroidism, and both of these conditions impair insulin secretion. It is possible, therefore, that the impaired insulin secretion of aging is not due to old age per se, but rather to associated CRF and excess PTH. The present study examined this issue in adult (6 month old) and senescent rats (2 year old) with and without CRF and excess PTH. Senescent rats without CRF had normal renal function and normal blood levels of PTH, and the values were not different from those observed in adult rats. Creatinine clearance in senescent rats with CRF was significantly (P less than 0.01) lower and serum levels of PTH were significantly (P less than 0.01) higher than in senescent animals without CRF and than in the adult rats as well. Only the senescent rats with CRF displayed glucose intolerance during intravenous glucose tolerance test. For any given level of blood glucose, plasma insulin levels were lower in senescent rats with CRF than in the adult rat or senescent animals without CRF.(ABSTRACT TRUNCATED AT 250 WORDS)

[Anti-inflammation and toxicity of radix Aconiti coreni and rhizoma Tyhon]

Rats, mice, pigeons and rabbits were employed to study the anti-inflammatory and toxic actions of Radix Aconiti coreni and rhizoma Tyhon. The result shows that Radix Aconiti coreni and rhizoma Tyhon have similar anti-inflammatory action. rhizoma Tyhon has an obvious stimulating effect on eye conjunctiva as well as throat and stomach mucosa, while Radix Aconiti coreni does not.

[A case-control study of dangerous factors related to infertility]

This paper reports the case-control study of dangerous factors related to infertility in Henan province during 1987-1988. There were two groups. One was a primary infertility group with 319 couples. The other was a normal fertility group with 714 couples, who were neighbours of the first group, among whom the women's age range was within 6 years old. The survey materials were analyzed by SAS programmes in the computer. The methods of analysis were single factor and logistic regression analysis of factors. The results of single factor analysis showed that in male, infertility had a close relationship with eating edible rude cotton seed oil; suffering from Varicocele; hydrocele of tunica vaginalis; sex dysplasia; breast dysplasia; puberty enuresis; parotitis after puberty; familial infertility and working under high temperature conditions. In female, menstrual disorder; a sexuality or pain during coitus; familial infertility; TB and other chronic diseases might be major contributors to the incidence of infertility. The results of logistic regression analysis of the factors related to infertility suggested that in male, eating edible rude cotton seed oil, suffering form varicocele; sex dysplasia; puberty enuresis; and in female, menstrual disorder; TB; consanguineous marriage, lower rate of coitus, frequent contact with pernicious substances might be major dangerous factors causing infertility. The results of the logistic regression analysis were different from those of the single factor analysis because the former not only analyzed the major influence of each factor but also considered the comprehensive effects of the relevant factors.

[The effect of hypocrellin A on the lipid bilayer of erythrocyte membrane]

In this paper, using human erythrocyte membrane, the effect of Hypocrellin A on the lipid bilayer of the membrane was studied by measuring the change of the fluidity of the membrane, the energy transfer of the fluorescent probes, the shift of the fluorescent emission peaks, and the split of band-a of Hypocrellin A. The results showed that in the presence of HA, the fluidity of erythrocyte membrane was increased, the fluorescence intensity of the probes was decreased, and the fluorescence peaks shifted blue. These phenomena took place more seriously with the increment of HA concentration. Meanwhile, the band-a of HA excitation spectra was splitted. It was suggested from all of the results that HA could significantly perturb the lipid bilayer of erythrocyte membrane, there were interactions existing between the Hypocrellin A and the membrane. The HA was mainly located in the middle range of the membrane lipid bilayer when in high concentration (mainly to the 12-16 positions of the long chain fatty acid).

Rapid diagnosis of Legionella infection by a nonisotopic in situ hybridization method

The authors report a nonradioactive adaptation of DNA hybridization technology for the direct detection of Legionella organisms in situ in routinely processed histologic specimens. The probe used consisted of synthetic oligodeoxynucleotides, complementary to the ribosomal RNA of all clinically relevant Legionella species, labeled with biotinylated dUTP at their 3' ends. By in situ DNA hybridization and detection with an avidin-alkaline phosphatase complex. Legionella was visualized by light microscopy within the alveoli of lung specimens in 9 of 13 direct fluorescent antibody- or culture-positive cases of Legionnaires' disease. No cross-hybridization was observed in lung specimens infected with Pseudomonas aeruginosa, Klebsiella pneumoniae, Streptococcus pneumoniae, or other pathogens. The authors' results illustrate a novel adaptation of in situ DNA hybridization techniques, usually used for viruses, to the detection of a bacterial organism. The method enables direct visualization of bacterial nucleic acid in infected tissues and may facilitate early diagnosis and treatment of legionellosis.

Immunohistochemical estrogen receptor assessment in hyperplastic, neoplastic, and physiologic endometria

Endometrial hyperplasias and some endometrial carcinomas arise in a setting of estrogen excess. Steroid hormones interact with cells via specific receptors; assessing receptor levels may indicate a tissue's potential for interaction with that hormone. To examine estrogen receptor (ER) levels in endometrial hyperplasia, endometrial carcinoma, and physiologically cycling endometrium, an immunohistochemical technique utilizing a monoclonal anti-estrophilin (estrogen receptor) antibody was applied to formalin-fixed, paraffin-embedded tissue. In complex hyperplasia and grade I adenocarcinoma, the mean percentages of epithelial cells demonstrating nuclear staining for ER was mildly decreased compared to proliferative endometrium. A trend was noted toward less ER staining in atypical hyperplasia compared to non-atypical complex hyperplasia. ER varied with physiologic cycling of the endometrium. ER was also present in atrophic endometrium, myometrium, adenomyosis, and leiomyomata. Immunohistochemistry permits localization of ER and is a useful technique in ER assessment of endometrial hyperplasias and carcinomas.

Histologic and immunohistochemical analysis of nine endometrial stromal tumors: an unexpected high frequency of keratin protein positivity

Nine cases of endometrial stromal tumors were examined by light microscopy and a battery of immunostains for diagnostic purposes. Eight of the cases were originally classified as endometrial stromal tumors and one as an epithelioid leiomyoma. Three of six (50%) endometrial stromal sarcomas stained positively for keratin/cytokeratin. All of these same tumors stained for vimentin. One case originally considered an epithelioid leiomyoma on light microscopy was later diagnosed as a uterine tumor with sex cord features following strong positive immunostaining with keratin/cytokeratin antibodies and negative staining with antidesmin. These results show that immunoreactivity for epithelial differentiation may be present in endometrial stromal tumors. The diverse immunostaining patterns of the stromal tumors reflect the probable histogenesis of these neoplasms from primitive totipotential stem cells which may differentiate along epithelial and various mesenchymal cell lines.

Downregulation of parathyroid hormone receptors in renal membranes from aged rats

The mechanism of the inhibition or blunting of parathyroid hormone (PTH)-stimulated Na(+)-Ca2+ exchange activity in renal cortical cells from aged rats was examined. The number of PTH binding sites in basolateral membranes prepared from adult (6 mo) and old (24 mo) rats was quantitated by the binding of the synthetic analogue 125I-labeled [Nle8,18, Tyr34]bPTH-(1-34) amide to the membrane. The maximum number of specific PTH binding sites, Bmax, was 92.7 +/- 9.3 and 36.7 +/- 6.1 fmol/mg protein, respectively, in membranes prepared from adult and old rats. The affinity of the receptor to PTH was unaffected with age. The level of PTH binding components (68 and 70 kDa) estimated by a ligand affinity blot technique using biotinylated bPTH-(1-34) as the ligand was similarly reduced in membranes isolated from senescent rats. To test the hypothesis that change in the number of PTH binding sites and level of PTH binding components represented an adaptive response to a high serum PTH level, rats were parathyroidectomized (PTX) and the changes were reexamined. Decreases in the number of PTH binding sites and PTH binding components were either partially or completely negated by the surgery. These findings suggest that the blunting of both the PTH-stimulated Na(+)-Ca2+ exchange and adenylate cyclase activities in the kidneys of aged rats was due, in part, to be loss of PTH receptors in basolateral membranes and that this defect could be partially reversed by removal of the parathyroid gland.

Infection of the heart by the human immunodeficiency virus

Heart muscle disease in the acquired immune deficiency syndrome (AIDS), characterized by electrocardiographic changes or congestive cardiomyopathy, is a documented clinical problem, but its pathogenesis is obscure. In AIDS the heart is known to be involved by a variety of opportunistic infections as well as Kaposi's sarcoma, but no causative relation with the development of cardiomyopathy has been established. This study reports evidence for direct infection of the heart in AIDS, not by an opportunistic pathogen but by the AIDS, not by an opportunistic pathogen but by the AIDS virus itself, the human immunodeficiency virus (HIV). For this study the technique of in situ deoxyribonucleic acid hybridization was applied to cardiac tissues obtained at autopsy from AIDS patients. Using sulfur-35-labeled ribonucleic acid probes encompassing the entire HIV genome, HIV nucleic acid sequences were detected in cardiac tissue sections from 6 of 22 patients examined who died of AIDS. The hybridization targets appeared to be cardiac myocytes, although their precise morphology was often obscured by the intensity of the signal. The myocardial cells showing a positive hybridization signal were sparse, often comprising only 1 or a few cells per section, and their number and location did not correlate obviously with any histopathologic or clinical evidence of heart muscle disease in these patients. It is conceivable that the presence of HIV nucleic acid sequences may represent a preclinical marker of impending AIDS-associated heart muscle disease. This sequela would not be recognized in many patients, including those in this series, who died rapidly of Pneumocystis carinii pneumonia, Kaposi's sarcoma and other well-documented manifestations of AIDS.(ABSTRACT TRUNCATED AT 250 WORDS)

[Role of "qi" in reaching affected area using acupuncture in "promoting blood circulation to remove blood stasis"]

In the present work, an experimental observation was carried out with the determination method of bioelectric impedance in 78 cases of chronic hepatitis, 58 cases of chronic obstructive pulmonary disease, 45 of obstructive thromboendarteritis and 65 of coronary heart disease, who were diagnosed definitely and possessed the symptoms and signs of blood stasis and produced change in hemodynamics. Yanglingquan (G. B. 34) and Zhangmen (Liv.13) acupoints on right side were needled and four indices of liver blood circulation were determined for chronic hepatitis. Bilateral Kongzui (Lu.6) acupoints were needled and seven indices of lung blood circulation were detected for chronic obstructive pulmonary disease. Acupoint along the pathway of channel were needled and six indices of blood circulation in the extremities were examined for obstructive thromboendarteritis. Bilateral Neiguan (P.6) acupoints were needled and four indices of the cardiovascular function were detected for coronary heart disease. Results showed 95 cases of the above four diseases having Qi reaching to affected area. 84 cases had propagated sensation along the channel. 67 cases had local sensation. Experimental results indicated that Qi reaching affected area produced obvious effects of dredging the meridian passage, and promoting blood circulation to remove blood stasis.