In situ prostate cancer gene therapy using a novel adenoviral vector regulated by the caveolin-1 promoter

Caveolin-1, a structural component of caveolae, is overexpressed in metastatic and androgen-resistant prostate cancer and highly expressed in tumor-associated endothelial cells. The mouse cav-1 promoter was cloned and placed upstream of the HSV-tk gene in an adenoviral vector (Adcav-1tk) and compared with a cytomegalovirus (CMV) or Rous sarcoma virus (RSV) promoter-driven HSV-tk, AdCMVtk and AdRSVtk vectors, respectively. Mouse and human prostate cancer cells and mouse endothelial cells were infected with Adcav-1tk, AdCMVtk or control vectors without the HSV-tk gene (Adcav-1 and AdCMV) and subsequently treated with ganciclovir (GCV). GCV-mediated in vitro cytotoxicity induced by the Adcav-1tk vector was comparable to that for AdCMVtk in multiple mouse and human prostate cancer cell lines. To evaluate the activity of Adcav-1tk in vivo, orthotopic mouse prostate cancer tumors were generated with RM-9 cells and injected in situ with Adcav-1tk, AdCMVtk, AdRSVtk, or AdCMVbetagal (control) and treated with GCV. All three HSV-tk transducing vectors produced statistically significant reductions in wet weight and increased apoptotic indices compared with the control vector. However, only Adcav-1tk produced significant necrosis, and only Adcav-1tk and AdRSVtk caused significant decreases in microvessel density. In conclusion, Adcav-1tk demonstrated efficacy in vitro and in vivo in preclinical models of prostate cancer. Our results suggest that the cav-1 promoter may have unique benefits in targeting gene therapy to prostate cancer and its associated vasculature.

Prostate-specific antigen response and systemic T cell activation after in situ gene therapy in prostate cancer patients failing radiotherapy

In an extended phase I/II study we evaluated 36 prostate cancer patients with local recurrence after radiotherapy who received single or repeated cycles of replication-deficient adenoviral vector (ADV)-mediated herpes simplex virus-thymidine kinase (HSV-tk) plus ganciclovir (GCV) in situ gene therapy with respect to serum PSA levels, alterations in immune cells, and numbers of apoptotic cells in needle biopsies. An initial cycle of HSV-tk plus GCV gene therapy caused a significant prolongation of the mean serum PSA-doubling time (PSADT) from 15.9 to 42.5 months (p = 0.0271) and in 28 of the injected patients (77.8%) there was a mean PSA reduction (PSAR) of 28%. It took a mean of 8.5 months for the PSA to return to the initial PSA (TR-PSA) value. A repeated cycle of gene therapy failed to significantly extend PSADT but did result in significant increases in PSAR (29.4%) and TR-PSA (10.5 months). Moderately increased serum adenovirus antibody titers were generally observed 2 weeks after initial vector injection. Also at this time there was a statistically significant increase in the mean percent of CD8(+) T cells positive for the HLA-DR marker of activation in peripheral blood (p = 0.0088). Studies using prostate biopsies obtained at the same time point demonstrated that vector DNA was detectable by PCR in most samples yet all patients remained positive for prostate cancer in at least one biopsy core. Further analysis demonstrated a correlation between the level of CD8(+) cells and the number of apoptotic cells in biopsies containing cancer cells (p = 0.042). We conclude that repeated cycles of in situ HSV-tk plus GCV gene therapy can be administered to prostate cancer patients who failed radiotherapy and have a localized recurrence. Biological responses to this experimental therapy including increases in PSADT, PSAR, and TR-PSA, and activated CD8(+) T cells present in the peripheral blood, were demonstrated. Interestingly, the density of CD8(+) cells in posttreatment biopsies correlated with the number of apoptotic cells.

[In vitro and in vivo experiment of transduction of reporter gene into tumors by E5 gene delivery system]

OBJECTIVE

To investigate the spectrum of tumors into which the E5 gene delivery system can transduce reporter gene so as to establish a platform technology that one gene delivery system can be used to treat multiple types of tumors.

METHODS

The E5 delecvery system was used to transduce reporter genes into various types of IGF I R positive tumor cell lines in vitro and into different IGF I R positive tumors transplanted subcutaneously in nude mice in vivo. The efficiency of trasduction was examined.

RESULTS

The E5 delivery system transferred reporter genes into five types of tumor cells that over-express IGFIR in vitro and transferred reporter genes into different tumors transplanted subcutaneously in nude mice that over-express IGFIR in vivo too. The transduction rate was positively correlated with the expression rate of IGFIR. However, the E5 delivery system failed to transfer reporter genes into tumor cedll lines in vitro and the tumors transplanted subcutaneously in nude mice in vivo, both of which were without IGF I R expression.

CONCLUSION

E5 delivery system has rather remarkable target-ability and extensive usefulness. It has the potentiality in gene therapy of cancer.

Dietary 4-HPR suppresses the development of bone metastasis in vivo in a mouse model of prostate cancer progression

The effects of the synthetic retinoid N-(4-hydroxyphenyl) retinamide (4-HPR) on prostate cancer metastasis in vivo were evaluated in the mouse prostate reconstitution (MPR) model. MPRs were produced by infection of either heterozygous (+/-) or nullizygous (-/-) p53-mutant fetal prostatic epithelial cells with the recombinant retrovirus Zipras/myc 9. Previous studies have documented that loss of p53 function potentiates metastasis in this model system. MPRs were grafted into homozygous (+/+) p53 male mice, fed a 4-HPR containing diet or a control diet and maintained until the status of tumor progression dictated sacrifice. Under these experimental conditions, treatment with 4-HPR did not have a significant effect on primary tumor wet weight for either p53 +/- or p53 -/- MPRs. For, p53 +/- MPRs the animals fed the 4-HPR diet had a slight improvement in survival and a significant reduction in the number of mesenteric metastases (P = 0.0477, t-test). Notably, in p53 +/- MPRs the incidence of metastasis to lumbar spine and sternum was 92% in the control animals compared to 54% in the 4-HPR treated animals (P = 0.035, chi2-test). In p53 -/- MPRs there was a trend toward a reduction in the number of soft tissue metastases to lung and liver in the 4-HPR group relative to the control diet group and a statistically significant reduction in the incidence of metastasis to bone was demonstrated in that 50% of control animals versus 30% of 4-HPR treated p53 -/- animals harbored bone metastases (P = 0 < 0.05, chi2-test). Cell lines were established from portions of the primary tumor and from selected metastatic deposits in each experimental group. Clonal analysis, by retroviral integration pattern, indicated increased clonal diversity in both the primary tumors and metastasis-derived cell lines from 4-HPR treated animals relative to the control animals. In vitro treatment with 4-HPR did not reveal discriminating differences between cell lines derived from primary tumors and bone metastases or control and treatment groups in regard to growth arrest or apoptotic responses. Overall these studies indicate limited anti-tumor and anti-metastatic activity in this highly aggressive in vivo mouse model of prostate cancer, yet 4-HPR treatment significantly suppressed the development of bone metastases in p53 +/- and p53 -/- MPRs revealing a novel and potentially clinically useful activity of this retinoid.

Caveolin-1 mediates testosterone-stimulated survival/clonal growth and promotes metastatic activities in prostate cancer cells

Previously, we demonstrated that up-regulation of caveolin-1 (cav-1) was associated with prostate cancer metastasis, biochemical recurrence after radical prostatectomy, and androgen insensitivity. The objective of this study was to characterize the regulation of cav-1 by testosterone (T) and to test the effects of cav-1 on prostate cancer cell survival/clonal growth and metastatic activities. Our results demonstrated that T up-regulated cav-1 protein levels in part through transcriptional regulation and significantly enhanced survival of prostate cancer cell lines ABAC3 and LNCaP after serum starvation (>40% and >60% increased viability, respectively) and in an extended clonogenic assay (approximately 4-fold and 6-fold increase in colonies, respectively). Importantly, antisense cav-1 inhibited the survival effects of T in these assay systems. Modest but not high levels of adenoviral vector-mediated cav-1 expression alone also significantly increased viability (>40%) and clonal growth (10-fold increase in colonies) after serum starvation. Analysis of spontaneous metastasis in stably transfected antisense cav-1 mouse prostate cancer cell clones demonstrated reduction of spontaneous lymph node metastasis incidence (13%), spontaneous lymph node metastasis volume (46%), and experimental lung metastasis incidence (40%) compared with vector control cell clones. Surgical castration further reduced spontaneous lymph node metastasis incidence and volume (18% and 28%, respectively) in antisense cancer cell clones, but not in vector control clones. Our studies demonstrate that cav-1 is a downstream effector of T-mediated prostate cancer cell survival/clonal growth and that modest levels of cav-1 can independently promote prostate cancer cell survival/clonal growth and metastatic activities.

[Apoptosis of bone marrow cells aplastic anemia patients treated with cyclosporin A]

OBJECTIVE

To evaluate the effects of cyclosporin A (CsA) on the apoptosis of bone marrow cells of aplastic anemia (AA) patients.

METHODS

The apoptosis of and Fas antigen expression on the bone marrow mononuclear cells (MNC) in 25 AA patients and 10 normal controls were assayed by TUNEL and FACS, respectively.

RESULT

The percentage of CD(34)(+) cells was decreased significantly in AA patients than in normal controls (P < 0.05), and so did the percentage of CD(34)(+)Fas(+) cells (P < 0.05). The percentage of apoptotic cells in AA patients was higher than that of controls (P < 0.01). After the patients were treated with CsA for 2 months, the percentage of apoptotic cells was decreased (P < 0.01). The percentage of CD(34)(+)Fas(+) cells was positively correlated with that of apoptotic cells in AA patients.

CONCLUSION

Fas is involved in the apoptosis of CD(34)(+) cells of AA patients. CsA could reduce the percentage of apoptosis of bone marrow cells in AA patients.

Role of digital artery adrenoceptors in Raynaud's disease

Raynaud's disease is characterized by excessive cutaneous vasoconstriction in response to ambient cold. A functional disturbance in the local regulation of digital vasomotion has been proposed. The purpose of this study was to determine whether there is an alteration in the postjunctional adrenergic receptors in the digital circulation of patients with Raynaud's disease. Furthermore, we sought to determine whether this abnormality was responsible for the excessive cold-induced vasoconstriction in these patients. Finger blood flow was measured by strain-gauge venous occlusion plethysmography in 10 patients with Raynaud's disease and in 10 normal volunteers in a 22 degrees C room. Measurements of finger blood flow and mean systemic arterial pressure were made during intra-arterial infusions of the alpha 1-adrenergic antagonist, prazosin, or the alpha 2-adrenergic antagonist, yohimbine, at room temperature and during local cooling of the hand. Basal finger blood flow in normal subjects was significantly greater than that of patients (8.6 +/- 2.7 vs 1.7 +/- 0.5 ml/100 ml per min; normal vs Raynaud's subjects; p < 0.05). In normal subjects, either prazosin or yohimbine induced dose-dependent increases in finger blood flow. The maximal increase in finger blood flow induced by prazosin was significantly greater than that in response to yohimbine (29.2 +/- 10.1 vs 2.8 +/- 2.1 ml/100 ml per min; prazosin vs yohimbine; p < 0.05). By contrast, in the Raynaud's patients, prazosin or yohimbine induced maximal increases in finger blood flow that were not significant (7.1 +/- 1.8 vs 5.0 +/- 2.2 ml/100 ml per min; prazosin vs yohimbine; p = NS). The response to prazosin in Raynaud's patients was significantly less than that of the normal volunteers (p < 0.05). In normal subjects, during intra-arterial infusion of vehicle alone, cooling induced a 52.6 +/- 5.8% reduction in finger blood flow. This cold-induced vasoconstriction was blunted, but not qualitatively altered, by either adrenergic antagonist. In the Raynaud's patients, during the intra-arterial infusion of the vehicle, cooling induced a 68.2 +/- 7.8% reduction in finger blood flow. Infusion of either adrenergic antagonist blunted, but did not qualitatively alter, the response to cold. Finger blood flow is less in patients with Raynaud's disease than in normal subjects when studied in a 22 degrees C room. In normal subjects, postjunctional alpha 1-adrenergic receptors appear to predominate in the control of digital vasoconstriction. Postjunctional alpha 1- and alpha 2-adrenoceptors play an equal role in adrenergic regulation of finger blood flow in patients with Raynaud's disease. In both normal and Raynaud's subjects, selective antagonism of alpha 1- or alpha 2-adrenergic receptors does not abolish local cold-induced vasoconstriction. Therefore, it is likely that a nonadrenergic mechanism contributes to local cold-induced vasoconstriction.

Compressing and focusing a short laser pulse by a thin plasma lens

We consider the possibility of using a thin plasma slab as an optical element to both focus and compress an intense laser pulse. By thin we mean that the focal length is larger than the lens thickness. We derive analytic formulas for the spot size and pulse length evolution of a short laser pulse propagating through a thin uniform plasma lens. The formulas are compared to simulation results from two types of particle-in-cell code. The simulations give a greater final spot size and a shorter focal length than the analytic formulas. The difference arises from spherical aberrations in the lens which lead to the generation of higher-order vacuum Gaussian modes. The simulations also show that Raman side scattering can develop. A thin lens experiment could provide unequivocal evidence of relativistic self-focusing.

Multicenter, double-blind, placebo-controlled, multiple-challenge evaluation of reported reactions to monosodium glutamate

BACKGROUND

The frequency of reactions reported to occur after the consumption of monosodium glutamate (MSG) is the subject of controversy.

OBJECTIVE

We conducted a multicenter, multiphase, double-blind, placebo-controlled study with a crossover design to evaluate reactions reportedly caused by MSG.

METHODS

In 3 of 4 protocols (A, B, and C), MSG was administered without food. A positive response was scored if the subject reported 2 or more symptoms from a list of 10 symptoms reported to occur after ingestion of MSG-containing foods within 2 hours. In protocol A 130 self-selected reportedly MSG-reactive volunteers were challenged with 5 g of MSG and with placebo on separate days (days 1 and 2). Of the 86 subjects who reacted to MSG, placebo, or both in protocol A, 69 completed protocol B to determine whether the response was consistent and dose dependent. To further examine the consistency and reproducibility of reactions to MSG, 12 of the 19 subjects who responded to 5 g of MSG but not to placebo in both protocols A and B were given, in protocol C, 2 challenges, each consisting of 5 g of MSG versus placebo.

RESULTS

Of 130 subjects in protocol A, 50 (38. 5%) responded to MSG only, 17 (13.1%) responded to placebo only (P <. 05), and 19 (14.6%) responded to both. Challenge with increasing doses of MSG in protocol B was associated with increased response rates. Only half (n = 19) of 37 subjects who reacted to 5 g of MSG but not placebo in protocol A reacted similarly in protocol B, suggesting inconsistency in the response. Two of the 19 subjects responded in both challenges to MSG but not placebo in protocol C; however, their symptoms were not reproducible in protocols A through C. These 2 subjects were challenged in protocol D 3 times with placebo and 3 times with 5 g of MSG in the presence of food. Both responded to only one of the MSG challenges in protocol D.

CONCLUSION

The results suggest that large doses of MSG given without food may elicit more symptoms than a placebo in individuals who believe that they react adversely to MSG. However, neither persistent nor serious effects from MSG ingestion are observed, and the responses were not consistent on retesting.

Subharmonic resonances in plasmas: exponential and superexponential growth of driven relativistic plasma waves

Subharmonic resonant beat-wave excitation of nonlinear relativistic plasma waves is studied analytically and in particle-in-cell simulations. We find that if the frequency separation of the lasers, Deltaomega, is 2omega(p) or 3omega(p) ( omega(p) is the plasma frequency), then plasma waves are still excited at omega(p) but they grow exponentially or superexponentially rather than secularly. Both of these subharmonic resonant instabilities saturate due to relativistic detuning. The analytical growth rates and saturation levels agree with the simulation results.

Mutual attraction of laser beams in plasmas: braided light

Using a variational method, we show that an effective attractive force exists between two Gaussian laser beams in a plasma because of a mutual coupling from relativistic mass corrections. The effective force can be generalized to other nonlinearities. This force can cause two laser beams to spiral around each other with a rotation period that is proportional to the Rayleigh length. These orbits are stable if the ratio of the orbit diameter to the laser spot size d(0)/W(0)</=sqrt[2]. Three-dimensional particle-in-cell simulations are presented which confirm the mutual attraction.

An increase in pectin methyl esterase activity accompanies dormancy breakage and germination of yellow cedar seeds

Pectin methyl esterase (PME) (EC 3.1.1.11) catalyzes the hydrolysis of methylester groups of cell wall pectins. We investigated the role of this enzyme in dormancy termination and germination of yellow cedar (Chamaecyparis nootkatensis [D. Don] Spach) seeds. PME activity was not detected in dormant seeds of yellow cedar but was induced and gradually increased during moist chilling; high activity coincided with dormancy breakage and germination. PME activity was positively correlated to the degree of dormancy breakage of yellow cedar seeds. The enzyme produced in different seed parts and in seeds at different times during moist chilling, germination, and early post-germinative growth consisted of two isoforms, both basic with isoelectric points of 8.7 and 8.9 and the same molecular mass of 62 kD. The pH optimum for the enzyme was between 7.4 and 8.4. In intact yellow cedar seeds, activities of the two basic isoforms of PME that were induced in embryos and in megagametophytes following dormancy breakage were significantly suppressed by abscisic acid. Gibberellic acid had a stimulatory effect on the activities of these isoforms in embryos and megagametophytes of intact seeds at the germinative stage. We hypothesize that PME plays a role in weakening of the megagametophyte, allowing radicle emergence and the completion of germination.

[Detection of fetal cells in maternal blood by fluorescence in situ hybridization]

OBJECTIVE

To isolate fetal nucleated cells from maternal blood and determine its fetal origin.

METHODS

Enrichment and isolation of nucleated cells in maternal blood from 20 samples in the first trimester of pregnancy, 20 samples in the mid-trimester of pregnancy, and 15 samples after delivery. Fluorescence in situ hybridization was performed using Y specific probe PY3.4 to identify fetal cells.

RESULTS

Fifteen women in the first trimester and 15 women in the mid-trimester of pregnancy carried male fetuses. The rates of positive cells were 1:6528.0 and 1:2783.8 respectively, and there was a highly significant difference when these rates were compared with the positive cells rate of the 10 female fetuses in the same trimesters. No significant difference in positive cells rate was found between 1 week after delivery and the mid-trimester of pregnancy, nor was it found between 3 months after delivery and the 10 samples of female fetuses in the same time.

CONCLUSION

These data suggest that fetal cells can be detected as early as from 50 days of gestation in maternal blood, in the meantime, the rate of fetal cells will increase with gestational age. One week after delivery, fetal cells still exist, and 3 months after delivery, the fetal cells will no longer be detected.

Caveolin-1 is regulated by c-myc and suppresses c-myc-induced apoptosis

Recent data indicating that overexpression of caveolin-1 as well as c-myc are relatively common features of advanced prostate cancer prompted us to test for potential cooperative interactions between caveolin-1 and c-myc that would be consistent with malignant progression. We used the well-characterized Rat1AmycERT cells to show that the caveolin-1 gene is down-regulated at the level of transcription by c-myc. By maintaining relatively high levels of caveolin-1 with an adenoviral vector or in stably transfected clones we show that caveolin-1 can suppress c-myc-induced apoptosis. Further we established human prostate cancer cell lines with the mycER construct and show that clones with increased caveolin-1 are more resistant to myc-induced apoptosis and have increased capacity for growth in soft agar when c-myc is activated.

Identification of differentially expressed genes in nasopharyngeal carcinoma by means of the Atlas human cancer cDNA expression array

PURPOSE

To investigate genes of critical areas, including cell cycle/growth control, apoptosis, oncogene/tumor suppressors and growth factor/cytokines, that are differentially expressed in nasopharyngeal carcinoma.

METHODS

The Human Cancer cDNA Atlas, which contains 588 genes relating to tumor biology, was used to screen normal nasopharyngeal tissue, nasopharyngeal cancer (NPC). The reverse transcription/polymerase chain reaction was used to confirm the expression pattern of some genes identified by Atlas hybridization.

RESULTS

The differentially expressed cell cycle/growth control regulators in NPC showed a stronger tendency toward cell proliferation with the up-regulation of cyclin D1, cyclin D2 etc. The expression pattern of apoptosis-related genes demonstrated the up-regulation of both anti-apoptotic factors such as the BCL-2-related protein A1, TRAF3, the inhibitor of apoptosis protein A1 (IAPI) and apoptotic pathway elements such as Fas/Apo-1, Apo-2 ligand etc. Among oncogenes/tumor suppressors, MDM2, STAT1 and STAT2 were found to be up-regulated in NPC. The expression profile of growth factors/cytokines showed the up-regulation of many growth-enhancing factors such as EGR1, tumor-derived growth factor 1, platelet-derived growth factor A chain etc. as well as Th1-type cytokines e.g. interleukin-1beta and interferons. A smaller number of genes were down-regulated in nasopharyngeal cancer, such as those encoding ERK1, Raf, secreted apoptosis-related protein 1, CD27BP, transforming growth factor beta2, pre-B-cell-stimulating factor homologue etc.

CONCLUSION

The consistent tendency toward cell proliferation, the possibility of a stronger antiapoptotic force that operates on the normal apoptotic pathway, or the autocrine or paracrine growth factors may account for the development of NPC. Some genes are reported for the first time to have changed expression in nasopharyngeal carcinoma. The simple, quick, and high-throughput method of profiling gene expression by cDNA array hybridization provides us with a quick overview of key factors that may be involved in NPC, and may identify genes suitable for further study of carcinogenesis mechanism or targets for possible molecular diagnosis or therapy.

Mouse prostate reconstitution model system: A series of in vivo and in vitro models for benign and malignant prostatic disease

BACKGROUND

An elucidation of the complex, morphological and molecular changes that underlie benign and malignant prostatic disease will likely lead to improved methods of diagnosis and therapy for those disorders. To identify and understand the interrelation of the phenotypic and genetic changes inherent in these important diseases requires the development and use of in vivo and in vitro models that closely mimic specific aspects of the disease process. Once the suspected molecular underpinnings of prostatic disease are uncovered, in vivo and in vitro models will be required for further testing of the functional significance of specific genetic alterations as they are identified. In addition models of prostatic disease are necessary to evaluate novel therapeutic approaches.

METHODS

The mouse prostate reconstitution (MPR) model system was developed more than a decade ago with these specific needs in mind. Over the years, specific modifications of the MPR model have demonstrated its versatility and applicability for the study of benign and malignant prostatic disease, including metastatic progression.

RESULTS

We discuss various modifications of the MPR model system made for its application to specific aspects of prostatic disease; the clinically relevant information that has been gleaned thus far from the use of this model system; and advances on the horizon for the expansion of its role in prostate research.

CONCLUSIONS

The MPR model system has contributed substantially to the understanding and treatment of benign and malignant prostatic diseases. Additional modifications in this series of in vivo and in vitro models will likely lead to further advances.

Characterization of the functionally related sites in the neural inducing gene noggin

Previously we have shown that blocking bone morphogenetic protein (BMP) receptor signaling by a dominant negative BMP receptor causes neurogenesis in Xenopus animal caps (ACs), whereas the physiological neural inducer noggin acts as a homodimer physically binding to BMP-4 and disrupting its signaling at the ligand level. The present study attempted to elucidate the relationship between the structure and function of noggin. By replacing some cysteine residues with serine residues through a site-directed mutagenesis strategy, we generated three noggin mutants, C145S, C205S, and C(218, 220, 222)S (3CS). Although mRNAs encoded by these mutants were translated as efficiently as wild-type (WT) noggin mRNA, they behaved differently when expressed in vivo. Expression of WT noggin or C205S in Xenopus ACs converted the explants (prospective ectoderm) into neural tissue, indicated by the neural-like morphology and expression of the pan neural marker NCAM in the ACs. In contrast, ACs expressing C145S or 3CS sustained an epidermal fate like the control caps. Similar results were observed in the mesoderm where C205S (but not C145S and 3CS) displayed dorsalizing activity as well as WT noggin. Altogether, our results suggest that Cys145 alone or Cys(218, 220, 222) as a whole in noggin protein is required for the biological activities of noggin, probably participating in the dimerization of noggin with BMP-4 or itself.

Review of alleged reaction to monosodium glutamate and outcome of a multicenter double-blind placebo-controlled study

Monosodium glutamate (MSG) has a long history of use in foods as a flavor enhancer. In the United States, the Food and Drug Administration has classified MSG as generally recognized as safe (GRAS). Nevertheless, there is an ongoing debate exists concerning whether MSG causes any of the alleged reactions. A complex of symptoms after ingestion of a Chinese meal was first described in 1968. MSG was suggested to trigger these symptoms, which were referred to collectively as Chinese Restaurant Syndrome. Numerous reports, most of them anecdotal, were published after the original observation. Since then, clinical studies have been performed by many groups, with varying degrees of rigor in experimental design ranging from uncontrolled open challenges to double-blind, placebo controlled (DBPC) studies. Challenges in subjects who reported adverse reactions to MSG have included relatively few subjects and have failed to show significant reactions to MSG. Results of surveys and of clinical challenges with MSG in the general population reveal no evidence of untoward effects. We recently conducted a multicenter DBPC challenge study in 130 subjects (the largest to date) to analyze the response of subjects who report symptoms from ingesting MSG. The results suggest that large doses of MSG given without food may elicit more symptoms than a placebo in individuals who believe that they react adversely to MSG. However, the frequency of the responses was low and the responses reported were inconsistent and were not reproducible. The responses were not observed when MSG was given with food.

[The expression of Fas antigen and plasma levels of sFas and sFasL in patients with aplastic anemia]

OBJECTIVE

To investigate the role of Fas/FasL system in the pathogenesis of aplastic anemia (AA) and its correlation with clinical status.

METHODS

Plasma levels of sFas and sFasL and the expression of Fas antigen on mononuclear cell (MNC) membrane in 32 AA patients and 24 normal controls were assayed by ELISA and FACS, respectively.

RESULTS

The percentage of CD(34)(+)Fas(+) cells was significantly higher (P < 0.05) in AA patients than that in normal controls, and the percentage of CD(34)(+)Fas(+) cells in severe AA patients was much higher than that in chronic AA patients (P < 0.05). The percentage of CD(34)(+)Fas(+) cells was negatively correlated with the course of disease. The levels of sFas were significantly lower (P < 0.05) in AA patients than that in normal controls, and the sFas levels in severe AA were much lower than those in chronic AA (P < 0.05). The percentage of CD(34)(+)Fas(+) cells was negatively correlated with sFas level.

CONCLUSION

Fas/FasL system aberration is involved in the pathogenesis of AA.

[A study on relationship between hypertension and polymorphism of ACE gene in male Yi people in Liangshan Yi autonomous prefecture, Sichuan]

OBJECTIVE

To explore relationship between polymorphism of ACE gene and hypertension.

METHODS

A cross-sectional study was conducted and PCR technique was used to analyze gene polymorphism.

RESULTS

Genotypes DD, ID and II of ACE gene accounted for 13.0% and 9.7%, 50.9% and 48.4%, and 36.1% and 41.9%, respectively, in the normotensives and hypertensives. Frequencies of I and D alleles for ACE gene were 61.6% and 66.1%, and 38.4% and 33.9%, respectively, in the normotensives and hypertensives. There was no significant difference in distribution of II, ID and DD genotypes and I/D allele frequencies of ACE gene between the hypertensives and normotensives in male Yi people.

CONCLUSION

Association between polymorphism of ACE gene and hypertension was uncertain.

A mutation in a methionine tRNA gene suppresses the prp2-1 Ts mutation and causes a pre-mRNA splicing defect in Saccharomyces cerevisiae

The PRP2 gene in Saccharomyces cerevisiae encodes an RNA-dependent ATPase that activates spliceosomes for the first transesterification reaction in pre-mRNA splicing. We have identified a mutation in the elongation methionine tRNA gene EMT1 as a dominant, allele-specific suppressor of the temperature-sensitive prp2-1 mutation. The EMT1-201 mutant suppressed prp2-1 by relieving the splicing block at high temperature. Furthermore, EMT1-201 single mutant cells displayed pre-mRNA splicing and cold-sensitive growth defects at 18 degrees. The mutation in EMT1-201 is located in the anticodon, changing CAT to CAG, which presumably allowed EMT1-201 suppressor tRNA to recognize CUG leucine codons instead of AUG methionine codons. Interestingly, the prp2-1 allele contains a point mutation that changes glycine to aspartate, indicating that EMT1-201 does not act by classical missense suppression. Extra copies of the tRNA(Leu)(UAG) gene rescued the cold sensitivity and in vitro splicing defect of EMT1-201. This study provides the first example in which a mutation in a tRNA gene confers a pre-mRNA processing (prp) phenotype.

Metastasis-related genes in prostate cancer

The identification of genes specifically related to the development of metastatic disease in prostate cancer is complicated by tumor cell heterogeneity and the presence of expressed sequences that are not related to metastasis. A system was designed to minimize these complications using differential display-polymerase chain reaction (DD-PCR) together with genetically paired cell lines derived from primary mouse prostate cancer and their associated metastases generated in vivo by the metastatic mouse prostate cancer reconstitution model. Using this system, a number of metastasis-related sequences were identified, including a cDNA that encodes caveolin-1.

[The development of a hemorrhologity observating and measuring instrument]

A new instrument for observing blood cell state and the process of variation on hemorrheology has been developed. There are three ways of shear rate: setting by hand, automatically setting and simulating pulsative state. It can provide different variable flow fields. The shear rate can be set in the range from 0.1 to 1000 s-1. It needs only a little blood. It can be easyly and rapidely operated. it has clear images. The hemorrheology state of blood cells can be directly perceived through thd instrument by eyes. The display and measurement and record of blood cell's hemorrheology state can be finished in real time dynamically and simultaneously.

[Systemic inflammatory response syndrome in critical patients - an analysis of 1,292 cases]

OBJECTIVE

To study the significance of the occurrence and the development of systemic inflammatory response syndrome (SIRS) in critical patients.

METHODS

The clinical data of 1292 patients accepted by our hospital in ten months from October 1995 to July 1996 were analyzed. The patients met at least two of the criteria for SIRS such as fever, hypothermia, tachycardia, tachypnea or abnormal white blood cell count.

RESULTS

1292 (67.7%) of the 1909 patients investigated met two or more of the criteria for SIRS. In the 1292 cases, those who met two, three or four of the criteria were respectively 467 (36.1%), 526 (40.7%) and 299 (23.1%). 149 patients (11.5%) in the 1292 cases died of multiple organ dysfunction syndrome (MODS). In which 33 (7.1%), 57 (10.8%) and 59 (19.7%) respectively in patients with two, three and four of the criteria for SIRS. The proportion of patients suffering from acute respiratory distress syndrome, metabolic function dysfunction, disseminated intravascular coagulation and acute renal failure increased with the increase in the number of SIRS criteria that the patients met and with the increase in the proportion of patients progressing from SIRS to septic shock. The mortality rate of the patients also gradually increased while the patients with SIRS were developing sepsis, severe sepsis and septic shock, but there was no statistical significance (P > 0.05).

CONCLUSION

It is suggested that bacterial infection, severe trauma and acute pancreatitis might cause SIRS and compensatory anti-inflammatory response syndrome might play an important role in the maintenance of internal environment of the body. A comprehensive understanding of SIRS might be of help to the management of critical diseases.

Suppression of caveolin expression induces androgen sensitivity in metastatic androgen-insensitive mouse prostate cancer cells

Although prostate cancer cells are often initially sensitive to androgen ablation, they eventually lose this response and continue to survive, grow and spread in the absence of androgenic steroids. The mechanism(s) that underlie resistance to androgen ablation therapy remain mostly unknown. We have demonstrated that elevated caveolin protein levels are associated with human prostate cancer progression in pathological specimens. Here we show that suppression of caveolin expression by a stably transfected antisense caveolin-1 cDNA vector converted androgen-insensitive metastatic mouse prostate cancer cells to an androgen-sensitive phenotype. Orthotopically grown tumors and low-density cell cultures derived from antisense caveolin clones had increased apoptosis in the absence of androgenic steroids, whereas similarly grown tumors and cells from vector (control) clones and parental cells were not sensitive to androgens. Studies using a representative antisense caveolin clone showed that selection for androgen resistance in vivo correlated with increased caveolin levels, and that adenovirus-mediated caveolin expression blocked androgen sensitivity. Our results identify a new candidate gene for hormone-resistant prostate cancer in man and indicate that androgen insensitivity can be an inherent property of metastatic prostate cancer.

Elevated expression of caveolin is associated with prostate and breast cancer

To identify genes associated with prostate cancer progression, we developed a strategy involving the use of differential display-PCR with a panel of genetically matched primary tumor- and metastasis-derived mouse prostate cancer cell lines. We isolated a cDNA fragment with homology to the mouse caveolin-1 gene. Northern blotting with this fragment revealed increased caveolin expression in metastasis-derived cell lines relative to primary tumor-derived cell lines. Western blotting with a polyclonal caveolin antibody confirmed increased caveolin protein in metastasis-derived mouse cell lines and expression in three of four human prostate cancer cell lines. Immunohistochemical analysis of a human prostate cancer cell line demonstrated a prominent granular pattern of caveolin accumulation. Subsequent analysis of mouse and human prostate specimens revealed minimal caveolin expression in normal epithelium with abundant staining of smooth muscle and endothelium. The frequency of caveolin-positive cells was increased in prostate cancer with markedly increased accumulation of caveolin and a granular staining pattern in lymph node metastatic deposits. In human breast cancer specimens, increased caveolin staining was detected in intraductal and infiltrating ductal carcinoma as well as nodal disease. Caveolin therefore appears to be associated with human prostate cancer progression and is also present in primary and metastatic human breast cancer.

[CYP2D6 and GSTM1 genetic polymorphism and lung cancer susceptibility]

OBJECTIVE

To evaluate the relationship between CYP2D6 and GSTM1 genetic polymorphism and lung cancer susceptibility among Cantonese in China.

METHODS

In a case-control study, PCR was used to identify CYP2D6 and GSTM1 genotypes and restriction enzyme BstNI was used to identify a specific point mutation of CYP2D6.

RESULTS

Between lung cancer patient group and normal control group CYP2D6 genetic polymorphism did not show frequency distribution differences but that of GSTM1 did (58.7% n = 46, 35.7%, n = 70, P < 0.05) OR = 2.56(1.11-2.44).

CONCLUSION

There is no association between CYP2D6 G-A mutation and lung cancer susceptibility, while individuals with GSTM1 -/- genotype are susceptible to lung cancer.

Reduced lysyl oxidase messenger RNA levels in experimental and human prostate cancer

To identify genes associated with prostate cancer progression, we developed a strategy involving the use of differential display PCR and a panel of genetically matched primary tumor- and metastasis-derived mouse prostate cancer cell lines. We analyzed sequences that were differentially stimulated by transforming growth factor-beta1 in primary tumor-versus metastasis-derived cell lines, based on our previous studies indicating that acquisition of differential responses to this growth factor could result in phenotypic traits that facilitate tumor metastasis from specific cell clones within the primary tumor. Using this system, we isolated and sequenced a cDNA fragment that encoded mouse lysyl oxidase (LO) and was induced by transforming growth factor-beta1 in primary tumor but not in metastasis-derived cells. Northern blotting analysis revealed increased LO expression in a panel of primary tumor cell lines but significantly reduced or nondetectable expression in their matched metastatic counterparts. Further in situ hybridization analysis revealed LO expression in normal mouse prostate epithelium but, in most cases, progressive loss of expression in primary prostate cancer and associated metastatic lesions. Importantly, in situ hybridization studies of normal human prostate and prostate malignancies revealed a similar loss of expression during progression to metastasis. The progressive loss of LO expression during prostate cancer progression provides information that may increase our understanding of the mechanisms that underlie this disease. In addition, LO may provide a useful molecular marker and/or establish a novel therapeutic target for prostate cancer.

[A deep regional impedance method measuring the blood distribution in the lung]

A new deep regional impedance method to measure the blood distribution in the lung has been developed. Using a multi-electrode system, the method simultaneously detects impedance information of chest, and back including lung and the thorax, then extracts the impedance information directly from lung with a special data processing approach in order to eliminate thorax effect on the measurement. The salt pool experiment and the preliminary application of measuring the blood distribution in the lung have been made. The results show that the method raises the relative sensitivity and the distinguishability of the blood measurement in the lung, and as a new deep regional impedance measurement method, it has a good prospects of clinical application in the future.

[The development of a multifunction shear flow field generating device]

A new shear flow field generating device has been developed. It can be widely used in the basic research of hemorheology, clinical test and measurement. It has rich functions and can make dynamic measurement of hemorheology parameters. There are three work ways of shear rate: setting by hand, automatically setting and simulating pulsative state. It can provide different variable flow fields. The shear rate can be set in the range from 0.1 to 1000 s-1.

[Antioxidative effect of constituents of herba Epimedii (ESPS)]

Herba Epimedii is a traditional Yang invigorating Chinese herb widely used in clinic. The experimental results have shown that ESPS obviously increases superoxide dismutase(SOD) activity of red cells and liver in aged mice and rats, and increases glutathione peroxidase(GSH-Px) activity of red cells in aged mice. On the other hand, ESPS obviously helps to reduce the content of serum and liver lipoperoxide(LPO) in aged mice and rats, as well as the content of lipofuscin(LF) in cardiac muscle of aged mice. The results suggest that being helpful in increasing SOD and GSH-Px activities and inhibiting the formation of LPO and LF, ESPS may be a good antiageing agent.

[Experimental study on bone formation in a denser coral used for repairing cortical defects in dogs]

The present study was designed to investigate a coral skeleton, Favites, which was originated from the reef builders in Hainan island, as a bone substitute. The coral Favites, like porites, is composed of anagonite (CaCO3), but contains less volume of porosity, higher strength and denser construction than Porites. After implanted into cortical bone defects in mandibles and femurs of dogs, skeleton fragment of coral Favites demonstrated good biocompatibility and biodegradability. A resorption of the implant and a simultaneous apposition of new bone was observed. Coral Favites was totally replaced by newly formed bone after a period of time from 6-8 months. Compared to Porites, Favites has a lower rate of resorption and therefore the defects of host bone are repaired completely without any lost of bone volume. The results showed that coral Favites may be used as a bone substitute for the segmental defects of mandibles.

[Effect of active constituents of Herba Epimedii on hypothalamic monoamine neurotransmitters and other brain functions in aging rats]

The active constituents of Herba Epimedii can raise the hypothalamic monoamine neurotransmitters levels in aging male rats and improve the learning and memory in aging rats and mice. It can also inhibit the activities of AchE both in brain tissues and whole blood in mice.

A novel electric design for electromagnetic stimulation--the Slinky coil

A novel coil design for inductive electromagnetic stimulation of neural cells has been simulated and experimentally tested. This coil improves the focal effect of a magnetic stimulator, and it reduces its inductance, hence the efficiency of the system is improved. The basic structure of the device is derived from the popular "Slinky" toy. The actual device is formed by winding different numbers of loops forming a helical coil on a half torus. The loops are bunched at the axis of the torus. The coil, due to its geometry, generates a unique distribution of eddy currents in nearby tissues which is favorable compared to a solenoid type stimulator. This renders the Slinky coil more selective than conventional coils used for magnetic stimulation. The distribution of eddy currents was analyzed using Matlab, following Faraday's Law of Induction. Improved focality permits the current through the coil to be reduced for the same effect. In addition, the reduced inductance of the Slinky coil decreases the power requirement; thus, the improved efficiency of the system may allow the generation of bursts of pulses, and expand the utilization of the system to possible functional activation of certain neuro-muscular structures when peripheral nerves are stimulated.

Loss of p53 function leads to metastasis in ras+myc-initiated mouse prostate cancer

To study the interactions between dominantly acting oncogenes and tumor suppressor genes we used p53 'knockout' mouse urogenital sinus tissue for retroviral transduction of ras and myc in the mouse prostate reconstitution (MPR) model system. Epithelial hyperplasia was observed in all wild-type p53 MPRs with one small focal cancer and no evidence of metastasis. Prostatic cancer was found in 100% of the heterozygous and homozygous p53 mutant MPRs with metastatic deposits in 95% of the mice. The pattern of metastasis was remarkably similar to that in human prostate cancer with gross metastatic deposits in the lung, lymph nodes, bone and liver of many animals. Progression of carcinomas in the ras+myc-initiated heterozygous p53 mutant MPRs was invariably associated with either complete loss, partial deletion or loss of expression of the wild-type p53 allele. Southern blotting analysis of proviral-cellular DNA junction fragments in primary carcinomas and cell lines derived from metastatic deposits revealed that metastases do not necessarily seed out from the most abundant clone in the primary carcinoma.

Hypotension preferentially induces c-fos immunoreactivity in supraoptic vasopressin neurons

Immunoreactivity to Fos protein (Fos-IR) was detected in rat hypothalamic neurons within 1 h of onset of hemorrhage by withdrawing 4-5 ml of blood, which lowered the arterial blood pressure to 50-70 mm Hg. About 70% of vasopressin (AVP)-containing neurons in the supraoptic nucleus (SON) and 20% in the paraventricular nucleus (PVN) expressed Fos-IR. In contrast, 5% of oxytocin (OXY)-containing neurons in the SON and < 1% in PVN were Fos-IR. Intravenous infusion of the vasodilating agent, nitroprusside, which lowered the blood pressure to levels comparable to that attained by hemorrhage, induced Fos-IR in greater than 65% of AVP-containing neurons in the SON, while relatively few AVP neurons in the PVN were Fos positive. These results suggest that hemorrhage or hypotension preferentially induces c-fos expression in supraoptic AVP-containing neurons.

Synaptic mechanisms in sympathetic preganglionic neurons

Intracellular recordings from sympathetic preganglionic neurons (SPNs) in adult cat and neonatal rat spinal cord slices reveal four types of synaptic potentials, namely, excitatory postsynaptic potentials (EPSPs), inhibitory postsynaptic potentials (IPSPs), and slow EPSPs in both preparations, and a slow IPSP in cat SPNs. Pharmacological studies show that glutamate or a related excitatory amino acid and glycine are the probable mediators of EPSPs and IPSPs. There may be heterogenous mediators of slow EPSPs; substance P, serotonin, norepinephrine, and epinephrine are all probable mediators of slow EPSPs in subpopulations of SPNs. In the case of slow IPSPs, norepinephrine appears to be the likely transmitter. Finally, stimulation of ventral roots elicits a synaptic potential that appears to be caused by glutamate released from afferent fibers in the ventral roots. Our results indicate that a multitude of synaptic mechanisms exist in the rat SPNs by means of which inputs arising from sensory and supraspinal neurons are processed in a timely and orderly manner, thus ensuring highly organized but differentiated outputs to multiple peripheral target cells.

Hypovolemia induces Fos-like immunoreactivity in neurons of the rat supraoptic and paraventricular nuclei

Immunoreactivities to Fos proteins were detected in numerous neurons in the supraoptic, paraventricular and accessory neurosecretory nuclei 1 h following withdrawal of 4-5 cc of blood from the rat femoral arteries. Few or no positive cells were observed in the same nuclei in sham-operated or control animals. It is concluded that hypovolemia induces c-fos expression in hypothalamic neurons known to be associated with blood volume/pressure regulation.

[Research on the processing of Angelica based on the analysis of water soluble constituents]

In this paper, a comparative study on the contents of water-soluble and alcohol-soluble tannin and ferulic acid in Angelica and its processed products is reported. The result shows that different processing methods have significant effects on the above constituents, thus administering to the interpretation of the theory of Angelica processing.

Effect of membrane potential and cellular ATP on glutathione efflux from isolated rat hepatocytes

total glutathione (GSH) efflux was studied in isolated rat hepatocyte suspensions at repleted GSH content (45-55 nmol/10(6) cells). The increase in concentrations of medium K+ in place of Na+ caused a parallel fall in membrane potential and total GSH efflux. Ouabain (1 mM) and replacement of Na+ with choline caused a gradual fall in membrane potential and GSH efflux. Hyperpolarization of hepatocytes with lipophilic anions, thiocyanate, and nitrate was associated with significantly increased efflux. Total GSH efflux was inhibited by increasing concentrations of fructose, antimycin A, and carbonyl cyanide p-trifluoromethoxyphenylhydrazone, and there was a direct relationship between the rate of efflux and cellular ATP. Changes in total GSH efflux were paralleled by changes in GSH determined by high-performance liquid chromatography. Vanadate markedly inhibited efflux but caused only a modest decrease in cellular ATP. Fructose, antimycin A, and vanadate did not affect membrane potential or cell volume under the conditions at which efflux was inhibited. These results suggest independent requirements for both membrane potential and ATP in the transport of GSH.

Kinetics of glutathione efflux from isolated rat hepatocytes

The characteristics and kinetics of glutathione (GSH) efflux were examined in homogeneous suspensions of freshly isolated rat hepatocytes. GSH efflux was measured as its linear accumulation in the suspension medium. Appearance of GSH extracellularly was reflected in a quantitative loss in cellular GSH. However, the total GSH remained essentially unchanged, indicating minimal net synthesis of GSH under these experimental conditions. GSH efflux was sensitive to temperature, with a calculated Q10 value of 2.3. A wide range of cellular GSH concentration ranging from near complete and moderate depletion to severalfold the control values was achieved by treatment of animals or cells with various GSH depletors or inducers. At physiological (fed) and elevated (3-methylcholanthrene- and CoCl2-induced) cellular GSH, the rate of GSH efflux was near maximum. The rate fell dramatically to 50% maximum at a GSH concentration equaling 35 nmol/10(6) cells. A 48-h fast resulted in a 40% loss of cellular GSH, with a corresponding decrease in efflux rates. Addition of GSH to the incubation medium had no effect on efflux rates. The relationship of GSH efflux to cellular GSH concentration was characterized by apparent sigmoidal saturation kinetics. The data were fitted well by the Hill model with the following kinetic parameters: Vmax = 0.25 nmol X 10(6) cells-1 X min-1, Km = 3.5 mM, and n = 3. These results correspond very closely to our previous findings in the perfused liver.