[Application of microfluidic assays for cardiovascular disease markers in early warning and rapid diagnosis].

Cardiovascular disease is a major threat to human health and has become the leading cause of death worldwide; therefore, early diagnosis and treatment are of great value. Due to its miniaturization, integration, and ease of operation, microfluidic technology enables the rapid, multi-target detection of cardiovascular disease markers and significantly facilitates the early and rapid diagnosis of cardiovascular disease. This article reviews the research progress of microfluidics in cardiovascular disease detection, analyzes its advantages and weaknesses in the rapid detection of protein, lipid, and nucleic acid biomarkers, hopes to provide a reference to promote the quick detection technology of cardiovascular disease, and thus proposes new considerations for the early management of cardiovascular disease.

Menthol in Combination with Iontophoresis Promotes Natamycin Penetration through the Cornea: In Vitro and In Vivo Studies.

We studied whether menthol can promote penetration of natamycin, a representative antifungal macrolide agent, through the cornea. Natamycin penetration was examined using an in vitro iontophoresis system that simulates clinical scenario; menthol (0.1-0.3%, w/v) was added to the donor reservoir of a standard Franz diffusion chambers. In vivo effects of menthol on natamycin penetration were examined in a set of bioassays using rabbits inoculated with Aspergillus fumigatus in the right eye. Potential irritation to the rabbit eye was examined using a standard test. Menthol significantly (p<0.05) potentiated the effects of iontophoresis on natamycin penetration. The optimal combination seemed to be 0.2% menthol in combination with 3 mA/cm2 iontophoresis.

[Epidemiological characteristics of COVID-19 monitoring cases in Yinzhou district based on health big data platform].

Objective: To understand the epidemiological characteristics of COVID-19 monitoring cases in Yinzhou district based on health big data platform to provide evidence for the construction of COVID-19 monitoring system. Methods: Data on Yinzhou COVID-19 daily surveillance were collected. Information on patients' population classification, epidemiological history, COVID-19 nucleic acid detection rate, positive detection rate and confirmed cases monitoring detection rate were analyzed. Results: Among the 1 595 COVID-19 monitoring cases, 79.94% were community population and 20.06% were key population. The verification rate of monitoring cases was 100.00%. The total percentage of epidemiological history related to Wuhan city or Hubei province was 6.27% in total, and was 2.12% in community population and 22.81% in key population (P<0.001). The total COVID-19 nucleic acid detection rate was 18.24% (291/1 595), and 53.00% in those with epidemiological history and 15.92% in those without (P<0.001).The total positive detection rate was 1.72% (5/291) and the confirmed cases monitoring detection rate was 0.31% (5/1 595). The time interval from the first visit to the first nucleic acid detection of the confirmed monitoring cases and other confirmed cases was statistically insignificant (P>0.05). Conclusions: The monitoring system of COVID-19 based on the health big data platform was working well but the confirmed cases monitoring detection rate need to be improved.

[A pathological report of three COVID-19 cases by minimal invasive autopsies].

Objective: To investigate the pathological characteristics and the clinical significance of novel coronavirus (2019-nCoV)-infected pneumonia (termed by WHO as coronavirus disease 2019, COVID-19). Methods: Minimally invasive autopsies from lung, heart, kidney, spleen, bone marrow, liver, pancreas, stomach, intestine, thyroid and skin were performed on three patients died of novel coronavirus pneumonia in Chongqing, China. Hematoxylin and eosin staining (HE), transmission electron microcopy, and histochemical staining were performed to investigate the pathological changes of indicated organs or tissues. Immunohistochemical staining was conducted to evaluate the infiltration of immune cells as well as the expression of 2019-nCoV proteins. Real time PCR was carried out to detect the RNA of 2019-nCoV. Results: Various damages were observed in the alveolar structure, with minor serous exudation and fibrin exudation. Hyaline membrane formation was observed in some alveoli. The infiltrated immune cells in alveoli were majorly macrophages and monocytes. Moderate multinucleated giant cells, minimal lymphocytes, eosinophils and neutrophils were also observed. Most of infiltrated lymphocytes were CD4-positive T cells. Significant proliferation of type Ⅱ alveolar epithelia and focal desquamation of alveolar epithelia were also indicated. The blood vessels of alveolar septum were congested, edematous and widened, with modest infiltration of monocytes and lymphocytes. Hyaline thrombi were found in a minority of microvessels. Focal hemorrhage in lung tissue, organization of exudates in some alveolar cavities, and pulmonary interstitial fibrosis were observed. Part of the bronchial epithelia were exfoliated. Coronavirus particles in bronchial mucosal epithelia and type Ⅱ alveolar epithelia were observed under electron microscope. Immunohistochemical staining showed that part of the alveolar epithelia and macrophages were positive for 2019-nCoV antigen. Real time PCR analyses identified positive signals for 2019-nCoV nucleic acid. Decreased numbers of lymphocyte, cell degeneration and necrosis were observed in spleen. Furthermore, degeneration and necrosis of parenchymal cells, formation of hyaline thrombus in small vessels, and pathological changes of chronic diseases were observed in other organs and tissues, while no evidence of coronavirus infection was observed in these organs. Conclusions: The lungs from novel coronavirus pneumonia patients manifest significant pathological lesions, including the alveolar exudative inflammation and interstitial inflammation, alveolar epithelium proliferation and hyaline membrane formation. While the 2019-nCoV is mainly distributed in lung, the infection also involves in the damages of heart, vessels, liver, kidney and other organs. Further studies are warranted to investigate the mechanism underlying pathological changes of this disease.

p16 gene expression in pancreatic cancer tissue and its importance in diagnosis.

The aim of this study was to assess the importance of p16 gene expressions in pancreatic cancer tissue for early diagnosis and treatment. Two groups were included in the study: an experimental group of 35 pancreatic cancer tissue specimens and a control group of 35 pancreatic cancer adjacent tissues collected during surgery. The expression of p16 gene in the two groups was observed using the immunohistochemical streptavidin peroxidase conjugated (S-P) method. The results were statistically interpreted using SPSS22.0 software. The positive expression rate of p16 in the experimental group was lower than that of the control group (p less than 0.05). Comparing the intensity of p16 gene expression, differentiation degree, clinical stage and metastases of nearby lymph nodes the differences had statistical significance (p less than 0.05). The intensity of p16 gene expression in high and medium differentiated pancreatic cancer group was higher than that of the low differentiated group. p16 gene expression in stages III and IV groups was lower than that in stages I and II groups. Differentiation degree, clinical stage, metastases of nearby lymph nodes and distant metastasss were negatively related with p16 gene expression (p less than 0.05). There was no correlation between age or gender and p16 gene expression. The decreased expression of p16 gene in pancreatic cancer tissue was negatively correlated with differentiation degree and clinical stage. Our results indicated that p16 can be used as a cue signal for diagnosing advanced pancreatic cancer.

First Report of Neofusicoccum parvum Causing Panicle Blight and Leaf Spot on Vitis heyneana in China.

The climbing vine, Vitis heyneana Roem. & Schult, is a member of the grape family endemic to Asia. Its fruits are used in wine production, and its roots, stems, and leaves can be used in medicinal materials. This plant is grown in Southwest China, as well as in India, Bhutan, and Nepal. Mulao Autonomous County in Guangxi Province is the only artificial cultivation area in China. During the summer of 2013, a panicle blight and leaf spot were detected on V. heyneana on four farms in Mulao Autonomous County. The symptoms were observed from the onset of florescence through fruit harvest. Brown lesions initially appeared at the base of a panicle and then extended to the whole panicle, finally causing the panicle to die and fruit to drop. When the disease developed on leaves, the symptom initially appeared as small dark brown circular spots, later enlarging into irregular spots (average diameter 6 mm) with a light brown center and dark brown rim. With severe disease, some individual leaves were affected by numerous spots, leading to premature senescence. Small sections of diseased tissue excised from 10 panicle and 10 leaf samples were plated on potato dextrose agar (PDA) and incubated at 28°C. Fungal colonies developed, initially with abundant white aerial mycelium, which turned olivaceous gray after 5 days and formed black pycnidia after 25 days. The conidia were hyaline, ellipsoidal to fusiform, externally smooth, thin-walled, and nonseptate. Thirty conidia were measured; the dimensions were 12.0 to 17.5 × 4.0 to 6.0 µm. Morphological characteristics of the isolates were similar to the descriptions of Neofusicoccum parvum (3). The isolate MPT-1 was selected as a representative for molecular identification. Genomic DNA was extracted and used for PCR to amplify the internal transcribed spacer (ITS) region and partial translation elongation factor 1-alpha (EF1-α) gene, using primers ITS1/ITS4 and EF1-728F/EF1-986R, respectively. The obtained ITS sequence (GenBank Accession No. KJ599627) and EF1-α sequence (KM921768) showed >99% homology with several GenBank sequences of N. parvum. Morphological and molecular results confirmed the isolate as N. parvum. For pathogenicity tests, detached, young healthy panicles and leaves of V. heyneana were surface-sterilized, wounded by sterile needle, and inoculated with mycelial plugs (3 mm in diameter) of four N. parvum isolates. Ten panicles and 10 leaves were used for every isolate. Control panicles and leaves were treated with sterile PDA plugs. All the samples were placed in a humid chamber (RH 90%, 28°C, 12 h of light) for 3 days. Symptoms similar to those observed in the field developed on all panicles and leaves inoculated with N. parvum isolates. N. parvum was reisolated from all inoculated, symptomatic tissues. The controls remained symptomless. N. parvum has been reported to cause trunk canker on V. vinifera (2), dieback on Cupressus funebris (3), and a leaf spot on Myristica fragrans (1). To our knowledge, this is the first report of N. parvum causing panicle blight and leaf spot on V. heyneana in China. Panicle blight caused a large number of fruits to drop and reduced the yield seriously. Some effective measures should be taken to control this disease. References: (1) V. Jayakumar et al. New Dis. Rep. 23:19, 2011. (2) J. Kaliternam et al. Plant Dis. 97:1656, 2013. (3) S. B. Li et al. Plant Dis. 94:641, 2010.

First Report of Lettuce Chlorotic Leaf Rot Disease Caused by Phytoplasma in China.

Lettuce (Lactuca sativa) as annual or biennial crop is an important vegetable in China. The lettuce variety Feiqiao, which is extensively cultivated in autumn and winter, is grown for its stem and is a characteristic species bred in Yong'an City. Since October 2005, a new disease of lettuce has been observed sporadically in the fields. Initially, chlorotic symptoms, or a faded red color, were observed on the inner leaves of the infected lettuce plants. Then, the inner leaves bleached and appeared pale, while the top leaves became straight and elongated, and stopped growing. Gummosis was observed at the base of young leaves, and the whole plant became stunted and died. The disease was named lettuce chlorotic leaf rot disease. In 2008, there was a disease outbreak in Yong'an City with an incidence of approximately 30%. In 2012, total DNA was extracted from 0.1 g of leaf tissue collected from 20 symptomatic and five asymptomatic lettuce plants using the CTAB method. A PCR analysis was performed using the phytoplasma-specific primer set R16mF2/R16mR1 (1). An approximately 1.4-kb amplicon was obtained from all 20 symptomatic plants, but no corresponding DNA fragment was amplified from the five asymptomatic plants. PCR products were cloned in Escherichia coli DH5α, using the pMD18-T vector (TaKaRa, Japan), and two isolates were sequenced. The two 1,431-bp sequences were identical (GenBank Accession No. KJ668578). A BLAST analysis revealed a 99% identity between lettuce chlorotic leaf rot phytoplasma and mulberry dwarf phytoplasma, a group 16SrI phytoplasma described by Win et al. in 2012 (3). After analyzing with iPhyclassifier, the virtual RFLP pattern derived from the 16S rDNA F2n/R2 fragment was most similar to the reference pattern of the 16Sr group I, subgroup B (NC_005303), with a pattern similarity coefficient of 0.99 (2). Additionally, the leaf veins and roots with symptoms were processed for ultrastructural examinations using transmission electron microscopy. Many typical phytoplasma-like bodies were observed in the sieve elements in the leaf veins and roots, and they were spherical to oval or dumbbell shaped and 200 to 800 nm in diameter. In agreement with these findings, seven strains of phytoplasma from 16SrI-A and 16SrI-B subgroups were reported in association with lettuce plants exhibiting various types of symptoms which were not completely consistent with those observed in China (4). To our knowledge, this is the first report of a phytoplasma associated with lettuce in China. References: (1) R. E. Davis et al. Microbiol. Res. 158:229, 2003. (2) W. Wei et al. Int. J. Syst. Evol. Microbiol. 57:1855, 2006. (3) N. K. K. Win et al. J. Gen. Plant Pathol. 78:264, 2012. (4) J. Zhang et al. Phytopathology 94:842, 2004.

Specific serology for emerging human coronaviruses by protein microarray.

We present a serological assay for the specific detection of IgM and IgG antibodies against the emerging human coronavirus hCoV-EMC and the SARS-CoV based on protein microarray technology. The assay uses the S1 receptor-binding subunit of the spike protein of hCoV-EMC and SARS-CoV as antigens. The assay has been validated extensively using putative cross-reacting sera of patient cohorts exposed to the four common hCoVs and sera from convalescent patients infected with hCoV-EMC or SARS-CoV.

Transforming growth factor-ß1 modulates lipopolysaccharide-induced cytokine/chemokine production and inhibits nuclear factor-κB, extracellular signal-regulated kinases and p38 activation in dendritic cells in mice.

Tolerogenic dendritic cells (DCs) are crucial for peripheral tolerance mediated by a variety of cytokines, including transforming growth factor-ß1 (TGF-ß1). We have observed that TGF-ß1-treated DCs (TGFß-DCs) were resistant to the maturation stimulus of lipopolysaccharide (LPS) and that TGF-ß1 down-regulated Toll-like receptor 4 (TLR4) expression on DCs. The purpose of this study was to analyze whether TGF-ß1 affected the production of cytokines/chemokines and proteins in the TLR4 signal transduction pathway following LPS stimulation. We observed that TGF-ß1 induced a significant increase in interleukin (IL)-10, impaired IL-12 secretion, and attenuated messenger RNA (mRNA) expression of chemokines CCL2, CCL3, and CXCL10 in DCs following LPS administration. We also noted that TGF-ß1 suppressed LPS-induced activation of nuclear factor (NF)-κB, extracellular signal-related kinases (ERK)-1/2, and p38 in DCs. Taken together, our results identified the suppressive effects of TGF-ß1 on TLR4 signal transduction, strengthening the notion that TGFß-DCs are a unique type of tolerogenic DC exhibiting distinct characteristics.

Phase II trial of a 2-h infusion of gemcitabine plus carboplatin as first-line chemotherapy for advanced non-small-cell lung cancer.

PURPOSE: To evaluate the efficacy and safety of the combination of using gemcitabine as a rate infusion of 10 mg/m(2) per min with carboplatin in front-line chemonaive patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Fifty-four chemonaive patients with stage IIIB or IV NSCLC have been included, 44 males and 10 females, with a median age 63 years (range 19-75). Thirty-two (59%) patients had adenocarcinoma, 13 (24%) squamous cell, 1 (2%) large cell carcinoma and 8 (15%) others. Eight (15%) had stage IIIB and 46 (85%) stage IV. Treatment was consisted of 1,200 mg/m(2) gemcitabine given as a 2-h continuous infusion (10 mg/m(2) per min) on days 1 and 8 of each cycle an AUC 5 carboplatin as on day 1, repeating each cycle for every 21 days. A total of 223 chemotherapy cycles were administered, with a median of four cycles per patient (range 1-6), and 15 (28%) patients received all six cycles. RESULTS: Of the 54 patients enrolled, all were evaluated for toxicity and 51 assessed for response. The overall response rate was 41% (95% confidence interval, 28-57%) with complete and partial responses of 4 and 37%, respectively. The median time to disease progression was 5.0 months (95% CI, 3.7-6.3 months), and median overall survival time was 11.5 months (95% CI, 9.9-13.1 months). One-year survival was 42%. The main grade 3-4 toxicity (according to the WHO scale) consisted of neutropenia (56%) and thrombocytopenia (57%). Patients were required platelet transfusion in 27 cycles (12%) and hematopoietic growth factors support care in 56 (25%) cycles. No bleeding episodes were recorded. Grade 3 nausea/vomiting occurred in 6% and grade 1-2 skin rash occurred in 43%. CONCLUSIONS: Prolonged gemcitabine infusion combined with carboplatin is manageable and tolerated, and its efficacy is similar to that of other chemotherapeutic schemes used for NSCLC treatment.

A candidate precursor to serous carcinoma that originates in the distal fallopian tube.

The tubal fimbria is a common site of origin for early (tubal intraepithelial carcinoma or TIC) serous carcinomas in women with familial BRCA1 or 2 mutations (BRCA+). Somatic p53 tumour suppressor gene mutations in these tumours suggest a pathogenesis involving DNA damage, p53 mutation, and progressive loss of cell cycle control. We recently identified foci of strong p53 immunostaining-termed 'p53 signatures'-in benign tubal mucosa from BRCA+ women. To examine the relationship between p53 signatures and TIC, we compared location (fimbria vs ampulla), cell type (ciliated vs secretory), evidence of DNA damage, and p53 mutation status between the two entities. p53 signatures were equally common in non-neoplastic tubes from BRCA+ women and controls, but more frequently present (53%) and multifocal (67%) in fallopian tubes also containing TIC. Like prior studies of TIC, p53 signatures predominated in the fimbriae (80-100%) and targeted secretory cells (HMFG2 + /p73-), with evidence of DNA damage by co-localization of gamma-H2AX. Laser-capture microdissected and polymerase chain reaction-amplified DNA revealed reproducible p53 mutations in eight of 14 fully-analysed p53 signatures and all of the 12 TICs; TICs and their associated ovarian carcinomas shared identical mutations. In one case, a contiguous p53 signature and TIC shared the same mutation. Morphological intermediates between the two, with p53 mutations and moderate proliferative activity, were also seen. This is the first report of an early and distinct alteration in non-neoplastic upper genital tract mucosa that fulfils many requirements for a precursor to pelvic serous cancer. The p53 signature and its malignant counterpart (TIC) underline the significance of the fimbria, both as a candidate site for serous carcinogenesis and as a target for future research on the early detection and prevention of this disease.

Prevention of murine acute graft-versus-host disease by recipient-derived TGFbeta1-treated dendritic cells.

Acute graft-versus-host disease (GVHD) remains the major barrier to allogeneic bone marrow transplantation (allo-BMT). Evidence has accumulated that transforming growth factor beta1-treated dendritic cells (TGFbeta-DC), deficient in surface costimulatory molecules, inhibit alloantigen-specific T-cell responses and induce graft hyporeactivity. To analyze the effect of TGFbeta-DC on GVHD after allo-BMT, 5.0 x 10(6) recipient-derived TGFbeta-DC were injected into C57BL/6 (H-2b) with bone marrow-splenocyte grafts from major histocompatibility complex (MHC) disparate BALB/c mice (H-2d). Survival analysis showed TGFbeta-DC cotransplantation resulted in significant prolongation of allograft survival, namely a mean survival time (MST) of 44.3 +/- 4.5 days, versus the untreated MST of 9.5 +/- 0.6 days (P < .01). However, mature DC aggravated the GVHD with an MST of 6.6 +/- 0.6 days (P < .01). In addition, the third-party C3H-derived TGFbeta-DC did not enhance the survival rate (MST = 9.7 +/- 0.5 days). Furthermore, serum IFN-gamma, IL-12, and IL-18 levels in TGFbeta-DC cotransplanted mice were reduced compared with untreated BMT hosts, while serum IL-10 levels were not changed. These results suggest that TGFbeta-DC cotransplantation may attenuate the severity of GVHD after BMT.

The catalytic and GAF domains of the rod cGMP phosphodiesterase (PDE6) heterodimer are regulated by distinct regions of its inhibitory gamma subunit.

The central effector of visual transduction in retinal rod photoreceptors, cGMP phosphodiesterase (PDE6), is a catalytic heterodimer (alphabeta) to which low molecular weight inhibitory gamma subunits bind to form the nonactivated PDE holoenzyme (alphabetagamma(2)). Although it is known that gamma binds tightly to alphabeta, the binding affinity for each gamma subunit to alphabeta, the domains on gamma that interact with alphabeta, and the allosteric interactions between gamma and the regulatory and catalytic regions on alphabeta are not well understood. We show here that the gamma subunit binds to two distinct sites on the catalytic alphabeta dimer (K(D)(1) < 1 pm, K(D)(2) = 3 pm) when the regulatory GAF domains of bovine rod PDE6 are occupied by cGMP. Binding heterogeneity of gamma to alphabeta is absent when cAMP occupies the noncatalytic sites. Two major domains on gamma can interact independently with alphabeta with the N-terminal half of gamma binding with 50-fold greater affinity than its C-terminal, inhibitory region. The N-terminal half of gamma is responsible for the positive cooperativity between gamma and cGMP binding sites on alphabeta but has no effect on catalytic activity. Using synthetic peptides, we identified regions of the amino acid sequence of gamma that bind to alphabeta, restore high affinity cGMP binding to low affinity noncatalytic sites, and retard cGMP exchange with both noncatalytic sites. Subunit heterogeneity, multiple sites of gamma interaction with alphabeta, and positive cooperativity of gamma with the GAF domains are all likely to contribute to precisely controlling the activation and inactivation kinetics of PDE6 during visual transduction in rod photoreceptors.

cGMP binding to noncatalytic sites on mammalian rod photoreceptor phosphodiesterase is regulated by binding of its gamma and delta subunits.

The binding of cGMP to the noncatalytic sites on two isoforms of the phosphodiesterase (PDE) from mammalian rod outer segments has been characterized to evaluate their role in regulating PDE during phototransduction. Nonactivated, membrane-associated PDE (PDE-M, alpha beta gamma2) has one exchangeable site for cGMP binding; endogenous cGMP remains nonexchangeable at the second site. Non-activated, soluble PDE (PDE-S, alpha beta gamma2 delta) can release and bind cGMP at both noncatalytic sites; the delta subunit is likely responsible for this difference in cGMP exchange rates. Removal of the delta and/or gamma subunits yields a catalytic alphabeta dimer with identical catalytic and binding properties for both PDE-M and PDE-S as follows: high affinity cGMP binding is abolished at one site (KD >1 microM); cGMP binding affinity at the second site (KD approximately 60 nM) is reduced 3-4-fold compared with the nonactivated enzyme; the kinetics of cGMP exchange to activated PDE-M and PDE-S are accelerated to similar extents. The properties of nonactivated PDE can be restored upon addition of gamma subunit. Occupancy of the noncatalytic sites by cGMP may modulate the interaction of the gamma subunit with the alphabeta dimer and thereby regulate cytoplasmic cGMP concentration and the lifetime of activated PDE during visual transduction in photoreceptor cells.

[A study on the anti-metastatic effects of CD3Ak cells in nude mice].

OBJECTIVE: To investigate whether cancer draining lymph node lymphocytes activated by CD3 McAB in vitro have anti-tumor effects in vivo. METHODS: Nude mice with highly metastatic human ovarian cancer were treated with CD3 McAB activated killer cells (CD3AK) from human ovarian cancer draining lymph node lymphocytes. 31 experimental nude mice were divided into 4 groups; the cisplatin group (7 mice), the CD3AK cells group (7 mice), the combined treatment group (7 mice), and control group (10 mice). Treatment began on the 10th day after tumor transplantation for a total of 80 days. RESULTS: The transplanted tumors disappeared in 1 mouse of CD3AK group, significant difference in the anti-metastatic effect was found between the CD3AK group (2/7 mice with metastasis) and the control group (8/10 mice with metastasis). Significant difference in average tumor volume was found between the CD3AK group (0.5788 +/- 0.2549) and the control group (1.5685 +/- 0.283). The tumor growth inhibition rate reached 63.1% in the CD3AK group. Significant difference in the serum level of progesterone was found between the CD3AK group (3.3843 +/- 0.5314) and the control group (6.3480 +/- 0.7615). Significant difference in the histiocyte increase in the lymph node sinuses was found between the CD3AK group (59/69) and the control group (55/94). CONCLUSION: These results suggest that CD3AK cells appear to be effective in tumor growth inhibition, anti-metastasis and enhancing host immunologic function.

Growth regulation of ovarian cancer cell line HO-8910 by transforming growth factor beta 1 in vitro.

OBJECTIVE: To further understand the role of growth regulation of human ovarian cancer cells by transforming growth factor (TGF) beta 1. METHODS: The cell proliferation, cAMP synthesis, gene expression, and induction of programmed cell death (PCD) in human epithelial ovarian cancer cell line HO-8910 cells exposed to TGF beta 1 in vitro were studied. RESULTS: TGF beta 1 inhibited cell growth and DNA synthesis, and induced G0/G1 arrest in cell cycle. It could also trigger PCD in cells. This induction of PCD may occur within G0/G1 phase. Meanwhile, the assay also showed that TGF beta 1 could inhibit the mRNA expression of c-myc, EGFR and TGF beta 1 genes in cells. CONCLUSIONS: TGF beta 1 can not only act as an autocrine to inhibit cell proliferation, but also trigger PCD in HO-8910 cells. These functions may be fulfilled through some specific signal transduction pathways.

[Induction of apoptosis in human ovarian cancer cell line HO-8910 by transforming growth factor beta 1].

OBJECTIVE: To investigate the mechanism of inhibitory effects of Transforming Growth Factor beta 1 (TGF-beta 1) on human ovarian cancer cell in vitro. METHODS: The possibility of induction of apoptosis in human ovarian cancer cell line HO-8910 cells after treatment with TGF-beta 1 was studied by using methods of DNA electrophoresis, P1-staining, TdT-mediated dUTP-x nick end labeling and flow cytometer assay (FCM); and the kinetic change of expression of c-myc was also studied by relative quantified RT-PCR. RESULTS: DNA-strand nicks were present in cells after treatment with TGF-beta 1 at the final concentration of 20 ng/ml for 36 hours. The percent of labeled cells reached 75.55% on the time of 48 hours, PI staining-FCM assay also showed subdiploid peak of apoptotic cells at the same time. The typical apoptotic DNA ladder was present in genomic DNA preparation after treatment with TGF-beta 1 for 60 hours, meanwhile, the expression of c-myc in cells started to decrease beginning at treatment for 9 hours. CONCLUSIONS: TGF-beta 1 can induce apoptosis in HO-8910; such an inductive effect may occur mainly in G0/G1 phase. The effects of TGF-beta 1 on the inhibited expression of c-myc and on the enhancement of cAMP concentration may also play important roles in the process of apoptotic induction.

3-Ketoglycoside-mediated metabolism of sucrose in E. coli as conferred by genes from Agrobacterium tumefaciens.

Escherichia coli strains that did not have the ability to use sucrose as a sole carbon source gained this ability after receiving a cloned fragment of DNA from Agrobacterium tumefaciens. No invertase was detected in the sucrose-metabolizing E. coli, but evidence for the activity of certain enzymes, known to be produced by biotype 1 strains of Agrobacterium, were found. Evidence was found for the presence of D-glucoside 3-dehydrogenase (G3DH) and alpha-3-ketoglucosidase. The activity of enzyme extracts on 3-ketosucrose also indicated that 3-ketoglucose reductase, or some enzyme that acts on 3-ketoglucose, was present in the Suc+ E. coli as well. The fragment was found to complement a G3DH mutant of A. tumefaciens and was also found to confer chemotaxis towards sucrose in E. coli.

[Establishment and characterization of a model of highly metastatic human ovarian cancer transplanted subcutaneously into nude mice].

A model of highly metastatic human ovarian cancer transplanted subcutaneously into nude mice was established (NMSO). Although the NMSO transplanted tumors were passaged 23 times, they retained their highly metastatic behavior. A total of 57 adult Balc/c nude mice (8-14 weeks old) were inoculated (SC) with tumor, the transplantations were 100% successful and the average survival period was 159.9 days. 47 mice were dissected and 42 mice were found to have metastatic tumors. The earliest appearance of metastasis was 56 dys. 18 male nude mice all had metastasis. Histology and ultrastructure showed that the metastatic tumors retained their malignant features and secreting function of the original poorly differentiated human ovarian serous papillary cystadenocarcinoma. FCM analysis gave a 1.4 DNA index and the chromosome mode number was 54 (hyper-diploid), exhibiting the features of human carcinoma. The detection of correlative label material showed that most cancer cells were ER and PR positive. The use of NMSO model may lead to better understanding of the mechanism of metastasis and help search for anti-metastatic agents.