Functional analysis of the CPS I upstream sequences with a cat assay

Expression plasmids (pKCPS-CAT) containing carbamyl phosphate synthetase (CPS I) upstream sequences of different lengths were constructed, and the function and characteristics of the sequences were studied with the CAT assay. Results showed that the CPS I upstream sequences exerted highly tissue-specific control on CPS I gene expression, and the -113 approximately -38 bp region relative to the cap site was found to be indispensable for CPS I gene transcription. The -1700 approximately -161 bp region contains sequences which confer an enhancing effect on CPS I gene transcription. Dexamethasone and thioproline (a differentiation inducer) showed enhancing effects on CPS I gene transcription in hepatoma cells. These results would have significance in studies on the gene regulation of CPS I associated with the mechanism of hepatocyte differentiation and carcinogenesis.

Isolation and characterization of PC-3 human prostatic tumor sublines which preferentially metastasize to select organs in S.C.I.D. mice

We have developed and partially characterized a mouse model system for studying human prostate tumor cell metastases in vivo. To develop this model we have selected highly invasive (3 x I.) and non-invasive (3 x N.I.) PC-3 human prostatic tumor sublines based on enhanced and diminished capacities to migrate across a reconstituted basement membrane barrier (Matrigel) in Boyden chamber chemotactic assays. When the 3 x I. cells were injected intravenously (i.v.) in the tail vein of severe combined immune deficient (scid) mice, the cells initially metastasized to a wide variety of tissues as demonstrated by using [125I] IUdR labeled cells and histology. Four distinct sublines were eventually isolated which preferentially metastasized at approximately 80% efficiency to the lumbar vertebrae (PC-3 ML), the mandibular region of the right cheek (PC-3 MC), the rib cartilage (PC-3 MR), and the right front knee bone (PC-3 MK), respectively. Implantation experiments at different sites indicated that organ metastases may somehow be conferred on the tumor subclones by the host tissue.

Regulation of kinesin expression and type IV collagenase secretion in invasive human prostate PC-3 tumor sublines

PC-3 human prostatic tumor sublines have been previously isolated which exhibit striking differences in their invasive and metastatic phenotypes. This work has been extended here to measure and compare the levels of kinesin, a microtubule-dependent translocator molecule, in the PC-3 sublines. Western blots, slot blots, radiolabeling, and immunoprecipitation analysis showed that kinesin was expressed in the highly invasive and metastatic sublines at levels which were elevated above the base-line levels observed in the parent PC-3 cells. In comparison, kinesin was not expressed in detectable amounts in the noninvasive cell lines. The conditioned medium of the metastatic PC-3 sublines contained a heat- and trypsin-sensitive protein which exhibited a dosage-dependent capacity to stimulate increased kinesin expression, type IV collagenase secretion, and invasion of Matrigel by the metastatic sublines. The noninvasive sublines failed to secrete a similar stimulatory factor(s) or respond to the conditioned medium of metastatic sublines. Various growth factors and cytokines tested (platelet-derived growth factor, epidermal growth factor, insulin-like growth factor, formylmethionineleucinephenylalanine) had no significant effect on either kinesin expression or protease secretion and invasion. Pertussis toxin blocked the stimulatory effects of the conditioned medium, but other agents known to interfere with adenylate cyclase pathways (i.e., cholera toxin, forskolin, 8-bromoadenosine) failed to block stimulation. The data show for the first time that kinesin, protease secretion, and the resulting invasion process may be regulated in a coordinated manner by an autocrine factor(s) which activates G-protein-dependent processes.

Arm abscesses caused by Clostridium botulinum

Wound botulism is an uncommon disorder that continues to be rarely reported in the United States. A 34-year-old intravenous heroin user was admitted to the Loma Linda, Calif., Veterans Administration hospital with multiple abscesses on his forearms. His clinical course was compatible with botulism, and his culture and serum were positive for Clostridium botulinum toxin type A. Early culture and/or serum identification can lead to prompt diagnosis, treatment, and improvement in the morbidity and mortality rates of this disease.

Induction of tissue-type plasminogen activator by ionizing radiation in human malignant melanoma cells

Two differently timed extracellular and intracellular enzymatic and mRNA peaks of tissue-type plasminogen activator (t-PA) were induced following ionizing radiation. The first peak appeared within 10 min following X-irradiation but rapidly declined. The appearance of early t-PA mRNA transcripts and enzymatic activity were not prevented by actinomycin D treatment. In contrast, cycloheximide prevented the early, minor enzymatic induction peak of t-PA. Stabilization of t-PA mRNA transcripts appears to be an early initial response of human cells to ionizing radiation, since the synthesis of new mRNA transcripts within the first 30 min was not observed via nuclear run-on analyses. Nearly 12 h following X-irradiation, a second major enzymatic peak of t-PA was observed. Cycloheximide or actinomycin D treatments blocked the later t-PA response. t-PA mRNA levels were induced greater than 100-fold in 4 h by ionizing radiation as assayed via Northern or nuclear run-on analyses. During the major induction period, t-PA mRNA transcripts reached their maximum levels at 4-8 h, and intracellular enzyme levels accumulated 6-8 h after X-irradiation. Unirradiated U1-Mel cells demonstrated only low basal levels of t-PA mRNA and enzymatic activity. Similar induction responses were found following UV-irradiation or 12-O-tetradecanoyl-phorbol-13-acetate (PMA) treatments. Normal human fibroblast (i.e., GM 2936B, GM2907A, and IMR-90) cells also demonstrated the induction of t-PA, although only one later enzymatic peak was detected. The induction of t-PA mRNA levels and intracellular and extracellular enzymatic activities for these cells were 50-fold lower than with U1-Mel cells given equitoxic doses of X-rays. Differential expression of t-PA in some tumor as compared to normal tissues may be utilized in future chemotherapeutic regimens.

[Inhibition by polyamine biosynthesis inhibitor DFMO of the growth of transplanted human colon cancer in nude mice]

A human colon cancer cell line Hce-8693 was heterotransplanted in nude mice. polyamine biosynthesis inhibitor alpha-difluoromethylornithine (DFMO) showed a marked reproducible inhibition in this model. The size and weight of transplanted tumor in DFMO group were smaller than those of the control group and the average inhibition rate was 72.8% (P less than 0.001). DFMO showed higher tumor inhibitory rate than 5-Fu (35.4%) (P less than 0.001). Furthermore, DFMO demonstrated less severe bone marrow inhibition in the nude mice than 5-Fu (20.0% vs 53.2%, P less than 0.001). There was no synergistic action in these two drugs at the experimental doses. The concentration of putrescine and spermidine in the serum and tumor tissue in the DFMO group were 70% lower than those of the control group (P less than 0.001). These results indicate that the anti-tumor effect of DFMO might be explained by the inhibition of polyamine biosynthesis and this study provides an experimental basis for future clinical application of DFMO.

Photodynamic therapy for 50 patients with skin cancers or precancerous lesions

Hematoporphyrin photodynamic therapy (HpD-PDT) was used to treat 50 patients (51 lesions) with skin cancers or precancerous lesions. The preliminary results were satisfactory, with 44 cases (45 lesions) obtaining excellent results, 4 cases good, 1 case fair, and 1 case poor. The effective rate was 98%, the significant remission rate 96%, and the complete remission rate 88.2%. Exposure to sunlight should be avoided after HpD injection, since it produces photosensitivity. A follow-up for 1 to 3 years confirmed that HpD-PDT is a good new adjuvant therapy for selected cases. It brings a hopeful future to the treatment of skin cancers.

[Effects of gossypol and GnRHa on the prostaglandins contents of endometriotic cell and in situ]

In order to study a direct effect of some traditional and western medicine on the prostaglandins (PGs) of endometriosis, endometriotic cell and endometrial cell in situ were cultured in vitro. 6-keto-PGF1 alpha and thromboxane (TXB2) were measured in the above cells using the RIA from the superfusates. These PGs changes after gossypol acetate, progesterone, danazol and gonadotrophin releasing hormone agonist (GnRHa) treatment were studied. High PGs levels were observed in endometriotic cell, and higher in endometrial cell in situ of patients than in endometrial cell of healthy persons (P less than 0.01). After treatment with drug (but not GnRHa), the prostacyclin (PGI2) and TXB2 content were reduced in endometriotic cell, and the TXB2 contents were reduced in endometrial cell in situ (P less than 0.01). These results indicate that endometriotic cell and endometrial cell in situ can produce more PGI2 and TXB2--at least in vitro, which perhaps may provide an explanation for the puzzling clinical phenomenon of endometriosis. Gossypol acetate, progesterone and danazol inhibit PGI2 and TXB2 content in endometrial cell of patients with endometriosis. It is pertinent to ask whether these drugs can be used to improve endometriosis-associated infertility or dysmenorrhea as well.

[Study on thixotropic parameters of whole blood from healthy children]

With low shear-30 rheometer, the authors used a modified protocol to measure thixotropic parameters of whole blood from 200 healthy newborns and children, so as to suggest the normal range of blood thixotropic parameters in four age groups, namely, the newborns, 1 year- group, 5 year- and 10-15 year group. The results demonstrated that the thixotropic parameters in the newborn group were higher than those in other three groups. However, these thixotropic parameters in the group 1-10 years were lower than those in the 10-15 year group. No significant sex differences were noted among the fore three groups, but sex differences appeared obviously in the 10-15 year group. It implied that the changes relying on the age is consistent with children's growth, development and physiologic activities.

Selective inhibition of natural killer but not natural cytotoxic activity in a cloned cell line by delta-9-tetrahydrocannabinol

Natural killer (NK) and natural cytotoxic (NC) activities are spontaneously generated against certain tumors in vitro and their contribution to tumor immunity is being extensively investigated. We report here that the interleukin-2 (IL-2)-dependent murine cell line, NKB61A2, which we recently found to express both NK and NC functions, can be modulated selectively by 9 delta-tetrahydrocannabinol (THC). THC, a major psychoactive metabolite of marijuana, could significantly inhibit NK activity without altering NC activity in NKB61A2 cells. Inhibition of NK function occurred at a post-binding stage because effector/target conjugation was unaffected by THC. With regard to NC function, neither the cytotoxic activity of the cells nor release of tumor necrosis factor was interrupted by THC. Therefore, THC may provide a useful tool for dissociating the mechanism of NK and NC activities within a single population of cells.

Human nonmuscle myosin heavy chains are encoded by two genes located on different chromosomes

We report the cloning of cDNAs encoding two different human nonmuscle myosin heavy chains designated NMMHC-A and NMMHC-B. The mRNAs encoding NMMHC-A and NMMHC-B are both 7.5 kb in size but are shown to be the products of different genes, which are localized to chromosome 22q11.2 and chromosome 17q13, respectively. In aggreement with previously reported results using avian tissues, we show that the mRNAs encoding the two myosin heavy chain isoforms are differentially expressed in rat nonmuscle and muscle tissues as well as in a number of human cell lines. The cDNA sequence encoding the 5' portion of the NMMHC-A isoform completes the previously published 3' cDNA sequence encoding a human myosin heavy chain, thus providing the cDNA sequence encoding the entire NMMHC-A amino acid sequence. Comparison of this sequence to cDNA clones encoding the amino-terminal one third of the NMMHC-B sequence (amino acids 58-718) shows them to be 89% identical at the amino acid level and 74% identical at the nucleotide level.

3 alpha-androstanediol glucuronide in virilizing congenital adrenal hyperplasia: a useful serum metabolic marker of integrated adrenal androgen secretion

To determine whether serum 3 alpha-androstanediol glucuronide (3AG) reflects the overall effect of integrated adrenal androgen secretion in the virilizing form of congenital adrenal hyperplasia (CVAH), circadian levels (0800, 1200, 1600, and 2000 h) of serum 3AG and 17-hydroxyprogesterone (17OHP) or 11-deoxycortisol (S), androstenedione (A), testosterone (T), and 24-h urinary 17-ketosteroids (17KS) were examined in seven patients (pts) with classical 21-hydroxylase deficiency (21OHD) and one pt with classical 11 beta-hydroxylase deficiency (11 beta OHD). Hormonal studies were conducted during the second day of dexamethasone (Dex) administration (2 mg/day). In five poorly controlled CVAH pts, including the 11 beta OHD pt, highly elevated baseline morning (AM) serum 17OHP or S as well as A levels, and elevated AM T levels in three pts decreased markedly in the evening (PM), while elevated serum 3AG showed no significant circadian changes; 17KS levels were markedly elevated for age. During Dex, moderately or slightly elevated AM 17OHP, A, or T in two to four pts with 21OHD decreased to the normal range in the PM. In the pt with 11 beta OHD, S, A, and T levels were suppressed. 3AG levels were modestly elevated or normal, without circadian changes, in these pts; 17KS levels were elevated or normal. In two other 21OHD pts, modestly elevated AM baseline 17OHP and A levels decreased in the PM; elevated AM T decreased in one pt in the PM; modestly elevated 3AG levels showed no circadian changes; 17KS levels were modestly elevated. During Dex, normal or slightly elevated serum steroids and 17KS levels were associated with normal or high normal 3AG levels without circadian changes. In one postpubertal female with 21OHD, modestly elevated AM baseline 17OHP levels decreased at 2000 h; normal A and T levels throughout the day and low normal 17KS were associated with slightly low 3AG levels, without circadian variation. During Dex treatment, normal 17OHP, A, T, and low 17KS levels were associated with low 3AG levels without circadian variation. In all pts as a group, an excellent correlation (r = 0.9) was found between either 0800 h or mean, or 2000 h serum 3AG levels and 17KS. In addition, AM and PM serum 3AG levels in five normal women were similar. We conclude that the high correlation between serum 3AG and urinary 17KS and the absence of a significant circadian variation in 3AG indicate that serum 3AG, regardless of sample time, is a useful metabolic index of integrated adrenal androgen secretion in CVAH.

[The value of residual volume testing in determining degree of emphysema in patients with pneumoconiosis]

A comparative study of chest roentgenograms and the value of RV/TLC% in determining degree of emphysema of patients with pneumoconiosis and workers exposed to dust was made in 400 cases. Accordance rate of RV/TLC% with roentgenograms in determining emphysema in the same subjects was 61.1% and that in the patients group, 67.7%. Moreover, the accordance rate increased with grade of pneumoconiosis diagnosed. The results showed that RV/TLC% was valuable in determining emphysema of patients with pneumoconiosis. The classes of degree of emphysema were proposed according to the testing value of RV/TLC%.

[Correlation between retinal nerve fiber layer defect, neuroretinal rim area and visual impairment in primary open angle glaucoma]

120 eyes of normal subjects, 150 eyes of ocular hypertension, and 132 eyes of primary open angle glaucoma (POAG) were examined the retinal nerve fiber layer (RNFL), neuroretinal rim area (NRA), visual field, dark adaptation and pattern reversal visual evoked potential (PVEP), revealing that RNFL defect and NRA correlated with visual field defect, threshold of dark adaptation and latency of PVEP. RNFL examination using red free photographic technique yielded 96% sensitivity in glaucoma detection and 95% specificity in identifying normal eyes. Modified semiquantitative criterion for assessing RNFL defect had a good reproducibility. The mean NRA in normal eyes was 2.22 +/- 0.35 mm2. Therefore, 95% of the normal subjects had rim areas greater than 1.64 mm2; 82% of patients with POAG had NRA less than 1.64 mm2. 20.1% of the eyes of ocular hypertension had RNFL defect and 37.6% had NRA below the 95% lower point, suggesting that some patients with increased intraocular pressure could have structural abnormalities. The authors proposed that ocular hypertension without visual field defect but with significant RNFL defect and/or NRA decrease should be regarded as in a preliminary stage of POAG.

Aetiologic study on an influenza-like epidemic in horses in China

About thirty thousands horses were affected and hundreds of them died in an epidemic caused by equine 2 influenza virus (H3N8) in China. The estimated morbidity and mortality accounted for 81% and 2%, respectively. The viral protein and RNA electrophoresis patterns revealed that the new isolates were antigenically different from the prototype strain influenza A/eq/Miami/1/63(H3N8). Therefore, the representative strain of the equine 2 subtype of influenza A virus recommended for producing reference reagents, vaccines, and for serological diagnosis must have been altered by antigenic drift.

[Gas chromatograms of fatty acids from Rickettsia and their similarities]

Fatty acid compositions of 7 strains of Rickettsia were analyzed by a on-line GC/MS system. These strains were R. prowazekii E, R. conorii Simko, R. rickettsii R, R. sibirica Barbash and 246, R. sinkiangensis Jinghe, and R. heilungkiangensis 54. The samples were purified by means of the concentrated salt-ether method. There were about 50 peaks in the fatty acid profiles, and 16 of these peaks were determined, i.e. C22:0, C19:0, C18:0, C18:1, C18:2, C17:0, C16:0, C16:1, 3-OH-C14:0, C15:0, C14:0, C13:0, 2-OH-C12:0, C12:0, 2-OH-C10:0, and C11:0. The major fatty acids were the saturated straight chain acids (e.g. C16:0, C18:0, C14:0) and the unsaturated straight chain acids (e.g. C18:1, C18:2, C16:1). Similarities of fatty acid profiles of tested strains were discriminated by the improved Kulik-Vincent method. The result showed that the KV's coefficient of strains Jinghe and 246 was 97.0%, and the KV's coefficient of strains 54 and the others was 81.6-94.6%.

[Effect of mutagenesis at Ser 177 residue in penicillin G acylase on activity of the enzyme]

The technique of cassette and site-specific mutagenesis were used to study the role of residue No. 177 in penicillin G acylase (PGA, EC 3.5.1.11). Ser is conserved at residue No. 177 in all penicillin binding proteins. We got a series of mutants in which the amino acid at residue No. 177 was replaced by other amino acids through the site-specific and cassette mutagenesis, and we characterized the mutants by colony hybridization, NIPAB paper test and DNA sequence analysis. These mutants all show no activity of enzyme, even if the Ser residue was replaced by Thr, Gly and Ala respectively. The results show that Ser residue may be essential for substrate-binding or catalysis of PGA.

[Effect of temperature on the expression of penicillin G acylase gene at the level of post-translational processing]

The expression of penicillin G acylase (PGA) gene is sensitive to temperature. Cells of E. coli DH 5 alpha harboring a plasmid pWGA carrying a gene for PGA produce active PGA at low level at 37 degrees C, but can synthesize significant amount of the enzyme below 30 degrees C. Active PGA is formed from a 94 KD precursor processed through remove of a signal peptide and a spacer peptide to yield an enzyme that contain a 23 KD (alpha) and 65 KD (beta) subunit. This paper reported the effect of temperature on transcription, translation, and post-translational processing of PGA gene expression. We detected the transcription of PGA gene by Northern blot, and found the amount of PGA mRNA at 37 degrees C much more than that 30 degrees C when the cells of DH 5 alpha (pWGA) were cultured. It is evident that the precursor processing step(s) is sensitive to temperature.

Oral clofilium produces sustained lowering of defibrillation energy requirements in a canine model

The effect of long-term oral administration of antiarrhythmic drugs on defibrillation energy requirements is not well understood. We examined the effect of clofilium, a drug that prolongs cardiac action potential duration without slowing cardiac conduction, on defibrillation energy requirements and ventricular effective refractory periods in a canine model during a 3-week period. Epicardial patch electrodes were implanted in 12 dogs, and baseline testing was conducted under fentanyl anesthesia on day 7. An oral clofilium (100 mg/day) regimen was started on day 8. Six clofilium-treated and six control dogs underwent repeated testing on days 14, 21, and 28 after surgery. Truncated trapezoidal shocks were given repeatedly at various stored energies in random order; delivered current and impedance were measured; and delivered energy was calculated. The energy and current for 50% success in defibrillation (E50 and I50, respectively) were determined. For control animals, E50 increased by a mean 34 +/- 78%, 60 +/- 83%, and 69 +/- 122% compared with baseline (day 7) on days 14, 21, and 28, respectively. In contrast, E50 in clofilium-treated dogs decreased by 39 +/- 62%, 24 +/- 33%, and 32 +/- 15% on days 14, 21, and 28, respectively. Mean current requirements (I50) remained relatively stable compared with baseline in control animals (-7 +/- 39%, +25 +/- 36%, +40 +/- 75% on days 14, 21, and 28, respectively). After clofilium administration I50 decreased by 36 +/- 22%, 32 +/- 17%, and 33 +/- 17% on days 14, 21, and 28, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

[Study of lipid peroxidation in patients with chronic renal failure]

The levels of lipid peroxide in plasma and erythrocyte membrane, the contents of blood superoxide dismutase and copper, zinc, iron in plasma, and erythrocyte membrane fluidity were investigated in patients with chronic renal failure (CRF). In comparison with the health subjects the levels of lipid peroxide in plasma and erythrocyte membrane were significantly higher, the contents of blood superoxide dismutase were significantly lower in the patients with CRF. The plasma copper increased and plasma zinc decreased, but plasma iron remained unchanges in the patients of CRF. We found that rises of lipid peroxide in erythrocyte membrane were closely related to changes of microviscosity in them.