Phorbol ester-induced apoptosis is accompanied by NGFI-A and c-fos activation in androgen-sensitive prostate cancer cells

We have previously demonstrated the induction of the early response transcription factor NGFI-A in castration-induced regression of the rat ventral prostate. We have developed an in vitro model to investigate the role of kinase signal transduction and early transcriptional regulation in apoptosis of androgen-sensitive prostate cells. Cell death was induced in the androgen-sensitive human prostate line, LNCaP, by addition of the protein kinase activator, 12-tetradecanoylphorbol 13-acetate (TPA). TPA-induced death of LNCaP cells was asynchronous and exhibited morphological and ultrastructural features indicative of apoptosis. Specifically, cytoplasmic contraction, condensation of nuclear chromatin, and formation of membrane-bound "apoptotic bodies" were observed. Additionally, the characteristic endonuclease-generated DNA ladder, commonly associated with apoptosis, was observed in TPA-treated LNCaP cultures. TPA-induced LNCaP apoptosis was preceded by rapid yet transient induction of the early response transcription factors NGFI-A and c-fos. In dose-response experiments, NGFI-A and c-fos gene activation parallels the induction of death in LNCaP cells. TPA-induced expression of NGFI-A and c-fos and death of LNCaP cultures were blocked by pretreatment with staurosporine, a potent inhibitor of several protein kinases. Based on these studies, we suggest that activation of a TPA-inducible kinase(s) mediates apoptosis of androgen-sensitive prostate cells by means of an intracellular pathway that may involve the transient activation of the early response transcription factors NGFI-A and c-fos.

Induction of zebrafish (Brachydanio rerio) P450 in vivo and in cell culture

1. Induction of zebrafish P450 by 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) was studied in liver tissue, primary liver cell culture and multipassage cell culture derived from zebrafish haploid and diploid embryos and liver. 2. TCDD induced two hepatic proteins (54 and 50 kDa) in vivo which were recognized by anti-trout P4501A1 IgG. The 54-kDa protein was induced by TCDD in primary and multipassage hepatocyte cultures and in haploid and diploid embryo-derived cells. The proteins in liver homogenates were not induced by aqueous exposure of zebrafish to beta-naphthoflavone (BNF). 3. Homogenates of zebrafish liver, cultured hepatocytes and embryo-derived cells also exhibited increased ethoxyresorufin O-deethylase (EROD) and 7-12-dimethyl-benz[a]anthracene (DMBA) hydroxylase activity following TCDD exposure.

[The use of finite population sampling and lot quality assurance sampling in estimating "immunization coverage rate" in villages (towns)]

We have used Finite Population Sampling and Lot Quality Assurance Sampling (LQAS) in a field survey of "immunization coverage rate" for EPI in three villages (towns) in Lanxi Zhejiang Province. The results showed that there was no significant difference (P > 0.05) between the rates of two samplings and between the rate of sampling and population. These results indicated that both Finite population Sampling and LQAS are cheap and simple, and can represent the immunization coverage level of population.

[Evaluation of the clinical acute electrophysiological effects of propafenone using transesophageal atrial pacing]

The clinical acute electrophysiological effects of propafenone were evaluated using transesophageal atrial pacing (TEAP) in 65 patients with various arrhythmias. The mean age of the patients was 41 years. Incremental pacing and programmed ectopic stimulation were performed on each patient before and during drug administration. Propafenone was given as a bolus injection of 1.5mg.kg-1 body weight followed by drip infusion at a rate of 1 mg.min-1. S-R, P wave, P-R and QRS intervals were prolonged from 194.43 +/- 21.59, 97.49 +/- 10.92, 148.00 +/- 16.20 and 82.21 +/- 7.18ms 223.00 +/- 29.25, 100.22 +/- 10.60, 166.60 +/- 20.10 and 86.54 +/- 7.19ms, respectively (P < 0.005), A-V conduction system effective refractory period (AVCSERP) was prolonged from 316.35 +/- 82.97ms to 360.31 +/- 82.67ms (P < 0.0001) in the treated group. There was no change of atrial ERP and QTc interval (P > 0.05). Fast and slow pathway ERP was prolonged by 13% and 28% of the control value, respectively (P < 0.015), and accessory pathway ERP was prolonged from 278.89 +/- 27.13ms to 305.56 +/- 33.58ms (P < 0.001), in the treated group. Sinus cycle length, corrected sinus nodal recovery time and total sinus-atrial conductive time were significantly prolonged (P < 0.0001). The results can partially explain the antiarrhythmic effects and the side effects of propafenone. TEAP is dependable in evaluating the clinical electrophysiological effects of drugs.

The first solid-state 171Yb nuclear magnetic resonance spectra

The first powder and magic-angle spinning (MAS) experiments on 171Yb are reported. The divalent ytterbium compound RbYbI3 was studied by solid-state 171Yb nuclear magnetic resonance (NMR) and a powder spectrum of axial symmetry was obtained. The principal components of the chemical shielding tensor were determined as sigma 11 = sigma 22 = -62 ppm and sigma 33 = 124 ppm. An inversion-recovery experiment showed an anisotropic relaxation behavior with the parallel component relaxing faster than the perpendicular component (T1 perpendicular = 426 ms, T1 parallel = 298 ma). The natural line width of 800 Hz, which corresponds to an effective T2 of 0.4 ms, was obtained from the MAS spectrum.

Somatotropin and insulin-like growth factor-I concentrations in plasma and milk after daily or sustained-release exogenous somatotropin administrations

Effects of daily injectable or sustained-release bovine somatotropin (bST) administrations on plasma and milk bST and insulin-like growth factor-I (IGF-I) concentrations were monitored in 74 lactating cows through early, mid- and late lactation. Treatments beginning at wk 4 of lactation were excipient (CO, 24 cows) at 2 wk intervals, daily injections of 10.3 mg bST (DI, 25 cows) and 350 mg sustained-release bST at 2 wk intervals (SR, 25 cows). The duration of treatments was 40 wk. Data were first analyzed for the overall mean concentrations covering the 40 wk treatment period. Overall mean plasma bST, milk bST and plasma IGF-I concentrations were significantly increased by both bST treatments (p < 0.05). On the other hand, milk IGF-I concentrations were significantly increased (p < 0.05) only in the DI group. Next, data were analyzed according to stage of lactation. The bST treatments resulted in significant increases (p < 0.05) in plasma and milk bST concentrations for all early, mid- and late lactation periods. Even though plasma IGF-I concentrations were higher (p < 0.05) in all lactation periods for bST treatment groups, higher milk IGF-I concentrations (p < 0.05) occurred only in mid- and late lactation periods for the DI group. The patterns of bST and IGF-I concentrations in milk follows those of the plasma after bST treatments.

Suitability of autoclaved tap water for preparation of ELISA reagents and washing buffer

The suitability of autoclaved tap water for the preparation of ELISA reagents and washing buffer was compared with that of ultrapure water, in a standard indirect ELISA for the detection of antibodies to pseudorabies virus (PRV). The performance of the assay, using autoclaved tap water (AT-ELISA) compared favourably to that of the standard assay, using ultrapure water (UP-ELISA) in detecting anti-PRV antibodies in sequential serum samples from a pig experimentally infected with PRV. While both the UP-ELISA and AT-ELISA proved reliable in detecting anti-PRV antibodies in a coded proficiency serum panel (n = 60), the AT-ELISA detected fewer positive sera than the UP-ELISA in evaluating a limited number (n = 80) of field samples. The results suggest that autoclaved tap water may be substituted for ultrapure water for the preparation of ELISA reagents when or where ultrapure water may not be available.

Specificity of DnaK-peptide binding

The sequence specificity of DnaK substrate binding has been studied using a peptide display library. Based on the amino acid patterns that appeared in this selection, short peptides were synthesized for direct measurements of DnaK affinity. The results show that peptides enriched in internal hydrophobic residues are preferential DnaK substrates, and negatively charged peptides have poor affinity. The isolated C-terminal domain of DnaK binds peptides. Peptide dissociation studies indicate that bound peptides are released from the C-terminal fragment and from DnaK at identical rates. ATP stimulates peptide dissociation from DnaK but not from the C-terminal fragment.

[Obliteration of empty sella for therapy of empty sella syndrome by transsphenoidal and transfrontal approach]

Seven cases of empty sella syndrome were reported, among them 2 cases were primary empty sella syndrome, 5 cases were secondary empty sella syndrome. 5 cases were operated with the obliteration by transsphenoidal approach, 2 cases were operated by transfrontal approach. 6 cases were cured, the symptoms in one case was not improved due to the primary hydrocephalus. This syndrome is associated with defect of sellar diaphragm, benign intracranial hypertension, long-term administration of Bromocriptine, surgery and radiotherapy of pituitary gland. Main clinical features are headache, damage of vision and visual fields, hypopituitarism. Obliteration of empty sella by transsphenoidal approach is a simple and effective method.

Analysis of messenger RNA within virions of IBV

The presence of subgenomic mRNAs (sgRNAs) in virions of infectious bronchitis virus was examined by probing Northern blots of RNA extracted from virions using as a probe a cDNA of the 3'-terminal nucleocapsid protein (N) gene. The sgRNAs were readily detected even after extensive purification of virions and after RNase A treatment of virions. The molar ratio of gRNA to each sgRNA was in the range 25 to 400 for IBV-M41 and 10 to 30 for IBV-Beaudette. After comparison with the molar ratios of genomic to intracellular viral sgRNAs it was estimated that the efficiency of incorporation of gRNA into virions was approximately 100 to 500-fold greater than for sgRNAs in the case of M41 and 20 to 100-fold for Beaudette, depending on the sgRNA species. It is concluded that sgRNAs can be present within IBV virions. Approximately 1 in 3 Beaudette virions and 1 in 20 M41 particles might contain a single copy of one sgRNA.

Quantitative single-photon emission computed tomography: basics and clinical considerations

Although quantitative single-photon emission computed tomography (SPECT) has been the goal of much research effort for a number of years, only recently has it received wide interest, especially for clinical applications. It has been increasingly recognized that the achievement of quantitative SPECT will increase the accuracy of measurements, such as dimensions of specific regions of interest, absolute amount of radioactivity, and dosimetry calculations, and substantially reduce reconstruction image artifacts and distortions, thus, greatly improving clinical diagnosis. This article provides a review of the definition of terms, major factors affecting SPECT quantitation and their degrading effects on SPECT image quality, and methods to compensate for these effects. Compensation methods include those that make certain approximations for ease of implementation and those that provide more accurate compensation by modeling the imaging process more exactly, usually at the cost of increased complexity and computational requirements. Different reconstruction and compensation methods may be compared through the use of phantom cardiac and brain SPECT studies. The clinical efficacy of the methods may be demonstrated by applying them to a clinical thallium-201 myocardial perfusion SPECT study. The results clearly demonstrate that, by modeling the imaging process and/or image degrading factors three-dimensionally, quantitative reconstruction and compensation methods provide the best image quality and quantitative accuracy. Important research efforts and developmental work being conducted currently to bring quantitative SPECT into routine clinical use are also discussed.

Effects of insulin-like growth factor-I and its analogues on bovine hydrogen peroxide release by neutrophils and blastogenesis by mononuclear cells

The biological potencies of recombinant human insulin-like growth factor-I (IGF-I) and two of its analogues were examined for hydrogen peroxide release by neutrophils and blastogenesis by mononuclear cells. The binding affinities of these peptides for bovine serum IGF-binding proteins (IGFBPs) and IGF-I receptors on bovine neutrophils and mononuclear cells were also investigated. Relative to control treatment containing no IGF-I, preincubation of neutrophils with 12.5 micrograms/l of IGF-I, des(1-3)IGF-I (an analogue of human IGF-I lacking the N-terminal tripeptide Gly-Pro-Glu) and long R3 IGF-I (an analogue of human IGF-I with arginine replacing glutamate at position 3 of human IGF-I and the N-terminal extension Met-Phe-Pro-Ala-Met-Pro-Leu-Ser-Ser-Leu-Phe-Val-Asn) increased the release of H2O2 by 65%, 64% and 32% respectively. However, the difference in stimulating the release of H2O2 between long R3 IGF-I and other two (IGF-I and des(1-3)IGF-I) was reduced at a dosage of 100 micrograms/l. In the absence or presence of 2.5% fetal calf serum (FCS), 100 micrograms/l of IGF-I, des(1-3)IGF-I but not long R3 IGF-I significantly stimulated thymidine incorporation into mononuclear cells. In addition, des(1-3)IGF-I was more potent than IGF-I in stimulating thymidine incorporation into mononuclear cells in the presence of 2.5% FCS.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of a depot injection of recombinant bovine somatotropin on follicular development and embryo yield in superovulated Holstein heifers

Superovulated Holstein heifers (n = 32) were given a depot injection of 500 mg recombinant bovine somatotropin (rBST) or vehicle at Day 4 of the estrous cycle (7 days before the first FSH injection); at Day 11, coincidentally with the first FSH injection; or at Day 15, the time of artificial insemination. Embryos were collected nonsurgically, and the number of corpora lutea was counted by ultrasonography at Day 7 after insemination. Blood samples were taken every second day, from Day 2 of the superovulatory cycle until the day of embryo collection, and were analyzed for progesterone, somatotropin and insulin-like growth factor-1 (IGF-1). Somatotropin-treated heifers at Day 11 had a significantly higher mean number of corpora lutea than the controls (18.1 vs 13.4; P </= 0.05). Day 4 treatment tended to increase the mean number of corpora lutea (15.4; P <- 0.10), and significantly increased the overall percentage of transferable embryos (74.6 vs 58.6%; P </= 0.01). In the control animals, plasma IGF-1 was uncorrelated to somatotropin (P > 0.63), but it was negatively correlated with progesterone (P </= 0.01), suggesting that IGF-1 production in the superovulated heifer may be related to ovarian development.

Mid-frequency hearing loss in rats following inhalation exposure to trichloroethylene: evidence from reflex modification audiometry

The present experiments were undertaken to characterize the hearing loss associated with 1,1,2-trichloroethylene (TCE) exposure. Adult male Long-Evans (LE) rats were exposed to TCE via inhalation (whole body) for 6 h/day for 5 days. The concentration-effect function (0-4000 ppm) was determined 3 weeks post-exposure. Animals were tested for auditory thresholds to 4, 8, 16, 24, 32, and 40-kHz tones using reflex modification audiometry. In a separate experiment, the time course of effects was determined by monitoring 16-kHz thresholds prior to, 1 h following each of the 5 exposure days, and 5 days, 1, 2, 4, 8, and 12 weeks post-exposure. At 14 weeks, these same animals were tested for thresholds to 0.5, 1, 2, 4, 8, 16, 24, 32, and 40-kHz tones. Results indicate elevated thresholds (hearing loss) for the 4000 ppm group at 8 and 16 kHz of approximately 18 and 30 dB, respectively. Time-course data demonstrated a rapid onset, a 20-dB loss at 16 kHz after the fifth exposure day, and a 40-dB loss by 2 weeks that persisted up to 14 weeks post-exposure. These data demonstrate an atypical and persistent, mid-frequency hearing loss in rats following inhalation exposure to TCE.

Clusters of interspersed repeated DNA sequences in the rice genome (Oryza)

We have characterized a repeated DNA sequence (RTL122) from rice (Oryza sativa L.) with respect to its organization in the rice genome and its distribution among rice and other plants. The results indicate that the RTL122 sequence is interspersed in the rice genome and limited to the genus Oryza. It is highly polymorphic and can be used to fingerprint rice varieties. A structure was observed in which several repeated sequences were clustered in DNA regions of 15-20 kb. We characterized three bacteriophage lambda clones that contained the RTL122 sequence. Southern analysis using probes derived from restriction fragments of the three lambda clones indicated that all fragments except one are interspersed repeated sequences and belong to different repeated sequence families. Subsequent slot blot hybridization showed that most of them are only present within the genus Oryza. Some of the Oryza-specific, physically linked sequences show the same phylogenetic distribution, which suggests that these sequences might have evolved in a coordinate fashion. On the other hand, some of the repeated sequences have a different distribution even though they are physically adjacent in the genome. We speculate that such blocks of interspersed repeated sequences may serve as hotspots for rapid changes in the rice genome.

Comparative toxicity of amyloid beta-peptide in neuroblastoma cell lines: effects of albumin and physalaemin

1. Synthetic amyloid beta-peptide was toxic to NB41A3 neuroblastoma cells in serum-free culture as judged by decreasing cell numbers and release of the cytosolic enzyme, lactic dehydrogenase. 2. Without amyloid beta-peptide, bovine serum albumin increased the number of cells surviving in culture. 3. In the presence of amyloid beta-peptide, BSA appeared to potentiate the amyloid beta-peptide toxicity. 4. The toxic dose response for amyloid beta-peptide varied between different cell lines (NB41A3, NB2a and IMR32), in a range of 100-1000 nM amyloid beta-peptide. 5. Amyloid beta-peptide toxicity was inhibited by the concurrent treatment of the cells with the tachykinin physalaemin with an ED50 of 10(-6) M.

Regulation of cytochrome P450 expression in a novel liver cell line from zebrafish (Brachydanio rerio)

The expression and induction of cytochrome P450 by 2,3,7,8-tetrachlordibenzo-p-dioxin (TCDD) and beta-naphthoflavone (BNF) in a new liver cell line from adult zebrafish (Brachydanio rerio) were studied. Subcellular fractions from control, BNF- or TCDD-treated cells did not show detectable bands in immunoblots probed with antibodies to the constitutive forms of trout P450 (LMC1, LMC2, LMC3, LMC4, and LMC5), suggesting that either zebrafish liver cells lack P450s closely related to those constitutively expressed in trout or that the concentrations of the orthologous P450s were too low to be detected. However, upon exposure to TCDD, the cells expressed a major immunoreactive 54-kDa protein and a minor 50-kDa protein recognized by antibodies to rainbow trout P4501A1. These immunoreactive proteins were observed in microsomal and mitochondrial fractions of TCDD-treated cells but were not detected in cell cultures treated with dimethyl sulfoxide (DMSO) (vehicle control) or BNF. The activities of ethoxyresorufin O-deethylase (EROD) and 7,12-dimethylbenzanthracene (DMBA) hydroxylase were markedly increased by TCDD but not by BNF in this cell line. EROD activity was more sensitive than DMBA hydroxylase activity of TCDD-treated liver cells to diagnostic inhibitors such as alpha-naphthoflavone and anti-trout P4501A1 IgG. The TCDD-treated cells converted DMBA to various metabolites, one of which is the putative proximate carcinogen, DMBA-3,4-diol. These results suggest that TCDD, but not BNF, induces one or possibly two forms of P450 immunochemically and functionally related to trout P4501A1, in cultured zebrafish liver cells.

Presence of subgenomic mRNAs in virions of coronavirus IBV

The presence of subgenomic mRNAs in virions of IBV was examined by probing Northern blots of RNA extracted from virions using as a probe a cDNA of the 3'-terminal nucleocapsid protein (N) gene. This detects all five mRNAs because of the 3'-coterminal, nested-set arrangement of coronavirus mRNAs. The mRNAs were readily detected even after extensive purification of virions and after RNase A treatment of virions. In sucrose gradients the peaks of virus particles, genomic RNA (gRNA), and mRNAs were coincident. Cellular mRNA was not detected in virions. The molar ratio of gRNA to each mRNA ranged from about 10 to 30 for IBV-Beaudette and 25 to 800 for IBV-M41. The molar ratio of genomic to intracellular viral mRNAs was also determined. From this it was estimated that the efficiency of incorporation of gRNA into virions was at least 20- to 100-fold greater, depending on the mRNA species, for IBV-Beaudette and 100- to 500-fold for IBV-M41. It is concluded that most virions contain only gRNA or contain only one species of mRNA on average in addition to gRNA.

[Cordyceps sinensis in protection of the kidney from cyclosporine A nephrotoxicity]

To explore the protective effect of cordyceps sinensis (CS) on cyclosporine A nephro-toxicity (CsA-Nx) and the possible mechanism, we studied the kidney changes induced by CsA in rats by light microscopy (LM), electronic microscopy (EM) and morphometrical analysis. At the 15th day after receiving CsA, prominent vacuolation and necrosis were noted microscopically in proximal tubular cells and mitochondria swelling electronmicroscopically. Morphometrical study showed that the epithelial areas of both proximal and distal tubules in the CS group were larger than those of the control group. There were obvious vacuolation (90%) and necrosis in proximal tubular cells at different stages of chronic CsA-Nx. Interstitial edema with mild fibrosis was observed. Mitochondria abnormality was seen electronmicroscopically. Morphometrical analysis showed that the epithelial cell areas of tubules and glomeruli were smaller in the CsA group than those in the CS group. Both acute and chronic experiments showed that CS could protect the kidney from CsA-Nx and ameliorate the glomerular and interstitial injuries.