Abstract P2-05-19: Pathway-based analysis of breast cancer

Objective: Although HER2 and ER pathways are predominant pathways altered in breast cancer, it is now well accepted that many other signaling pathways are also involved in the pathogenesis of breast cancer, especially in triple negative breast cancer. The understanding of these additional pathways may assist in identifying new therapeutic approaches for breast cancer.

Methods: 13 invasive ductal carcinoma tissues and 5 benign breast tissues were analyzed for the mRNA expression level of 1243 cancer pathway-related genes using SmartChip (WaferGen, CA), a real-time PCR-base method. In addition, the levels of 154 cancer pathway-related proteins and phosphoproteins were measured using our innovative Protein Pathway Array.

Results: Out of 1,243 mRNAs, 68.7% were detected in breast cancer and 73 mRNAs were statistically significant between benign and cancer tissues. Of these mRNAs, 105 only expressed in breast cancer tissues and 33 mRNAs only expressed in normal breast tissues. Out of 154 proteins and phosphoproteins, 39% were detected in cancer tissues and 50 proteins were significantly differentiated between tumor and normal tissues. Interestingly, only 3 genes (CDK6, Vimentin and SLUG) showed decrease of both protein and mRNA. Six proteins (BCL6, CCNE1, PCNA, PDK1, SRC and XIAP) showed differentially expressed between tumor and normal tissues but no differences were observed at mRNA levels. Analyses of mRNA and protein data using Ingenuity Pathway Analysis showed more 15 pathways were altered in breast cancers and 6 of them shared between mRNAs and proteins, including p53, IL17, HGF, NGF, PTEN and PI3K/AKT.

Conclusion: There is a broad dysregulation of various pathways in breast cancer both at protein levels and mRNA levels. It is important to note that mRNA expression does not correlate with protein level, suggesting that different regulation mechanisms between proteins and mRNAs.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-05-19.

An ammonium sulfate/ethanol aqueous two-phase system combined with ultrasonication for the separation and purification of lithospermic acid B from Salvia miltiorrhiza Bunge

We studied the effect of ultrasonication extraction technology combined with ammonium sulfate/ethanol aqueous two-phase system (ATPS) for the separation of lithospermic acid B (LAB) from Salvia miltiorrhiza Bunge. According to the literature and preliminary studies, ammonium sulfate concentration, ethanol concentration, pH, ultrasonication power, ultrasonication time and the ratio of solvent-to-solid were investigated using a single factor design to identify the factors affecting separation. Taking into consideration a simultaneous increase in LAB recovery (R (%)) and partition coefficient (K), the best performance of the ATPS was obtained at 25°C and pH 2 using ammonium sulfate 22% (w/w) and ethanol 30% (w/w). To keep the solvent-to-solid ratio at 10, response surface methodology was used to find the optimal ultrasonication power and ultrasonication time. Quadratic models were predicted for LAB yield in the upper phase. Optimal conditions of 572.1 W ultrasonication power and 42.2 min produced a maximum yield of LAB of 42.16 mg g(-1) sample. There was no obvious degradation of LAB with ultrasound under the applied conditions, and the experimental yield of LAB was 42.49 mg g(-1) sample and the purity was 55.28% (w/w), which was much higher than that obtained using conventional extraction. The present study demonstrated that ultrasound coupled with aqueous two-phase systems is very efficient tool for the extraction and purification of LAB from Salvia miltiorrhiza Bunge.

Expressed sequence tag-simple sequence repeat-based molecular variance in two Salicornia (Amaranthaceae) populations

Salicornia spp is one of the most salt-tolerant vascular plants and is native to salt marshes and estuaries. We developed expressed sequence tag derived-simple sequence repeat (EST-SSR) markers for estimating genetic diversity and marker-assisted Salicornia breeding. Six polymorphic EST-SSRs of 40 detected 27 alleles, ranging from three to five alleles per locus. The average number of alleles per locus was 4.33 and 4.17, and the major allele frequency at locus DY529765 was high, being 0.859 and 0.857 in S. bigelovii and S. europea, respectively. Gene diversity, heterozygosity and polymorphism information content were highest at locus DY529950 and similar in these two species. Gene diversity increased with increase in the number of alleles that had a low major allele frequency at a locus. Six polymorphic loci effectively discriminated 46 taxa into three clusters via different analyses. Significant deviation of F(ST) from zero in three suggested populations for six loci indicated population differentiation and limited gene flow among them. A reduced median network established that taxon SB65 is primitive. SMART (simple modular architecture research tool) analysis of peptide sequences of six EST-SSRs showed that loci DY529765, DY529950 and EC906203 contained transmembrane, TLC, AgrB and NTR domains and might be involved in salinity stress tolerance. These EST-SSRs are a valuable resource for marker development and may be useful in marker-assisted Salicornia breeding.

One-year monthly survey of rotavirus, astrovirus and norovirus in three sewage treatment plants (STPs) in Beijing, China and associated health risk assessment

To evaluate the presence and distribution of the three main viruses (rotavirus, astrovirus, and norovirus) responsible for human acute gastroenteritis in sewerage systems, a one-year study was carried out in Beijing, China. A total of 96 samples of influent and effluents from three sewage treatment plants (STPs) were collected from November 2006 to October 2007. Silica was used to concentrate viral particles from water samples and a reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) method was used for detection of viruses. Virus(es) could be detected in 35.4% (34/96) of the water samples analysed, where human rotavirus was the most frequently detected one (32.3%, 31/96), followed by human astrovirus (6.3%, 6/96) and human norovirus (3.1%, 3/96). According to the quantitation results of rotaviruses, which were gained by the real-time quantitative RT-PCR method with SYBR Green I, it was known that the distributions of rotaviruses in influents and effluents of three STPs were quite similar, i.e., abundant in cold weather (from October to March) and less prevalent in warm weather (from April to September). According to the estimated exposure dose and exposure frequency, as well as the acceptable annual risk level, it was shown that the rotaviruses in the reused wastewater after conventional treatment process presented potential risk to human health through both occupational and accidental exposure.

One-year monthly survey of rotavirus, astrovirus and norovirus in three sewage treatment plants in Beijing, China and associated health risk assessment

To evaluate the presence and distribution of the three main viruses (rotavirus, astrovirus, and norovirus) responsible for human acute gastroenteritis in sewerage system an one-year study was carried out in Beijing, China. A total of 96 samples of influent and effluents from three sewage treatment plants (STPs) were collected from November 2006 to October 2007. Silica was used to concentrate viral particles from water samples and a reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) method was used for detection of viruses. Viruses could be detected in 35.4% (34/96) of the water samples analyzed, where human rotavirus was the most frequently detected (32.3%, 31/96), followed by human astrovirus (6.3%, 6/96) and human norovirus (3.1%, 3/96). According to the quantitation results of rotaviruses, which were gained by the real-time quantitative RT-PCR method with SYBR Green I , it was known that the distributions of rotaviruses in influents and effluents of three STPs were quite similar, i.e., abundant in cold weather (from October to March) and less prevalent in warm weather (from April to September). According to the estimated exposure dose, exposure frequency, as well as the acceptable annual risk level, it was shown that the rotaviruses in the reused wastewater after conventional treatment process presented potential risk to human health through both occupational and accidental exposure.

Annexin A1 expression and its prognostic significance in human breast cancer

Annexin A1 (ANXA1) is a calcium- and phospholipid-binding protein and is considered to play an important role in tumorigenesis. However, the correlation between ANXA1 expression and tumor clinicopathological features in patients with breast cancer remains unclear. This study investigated the prognostic value of ANXA1 protein as breast cancer marker. Tissue microarray blocks, containing 20 cases of non-tumor breast tissue, 20 cases of benign breast lesion and 135 cases of breast cancer (107 with lymph node metastasis), were constructed. Expression of ANXA1 in these specimens was analyzed using immunohistochemistry. In non-tumor tissue and benign breast lesions, myoepithelial cells showed strong expression of ANXA1. Negative ANXA1 expression was significantly associated with advanced disease stage (P<0.05), especially pathological-N stage (P<0.01). The patients with loss of ANXA1 expression in tumor tissues showed a significantly worse overall survival compared with positive ones (P<0.05). ANXA1 did not correlate well with estrogen receptor (ER), progesterone receptor (PR) and HER2/neu status. Moreover, the level of ANXA1 expression in lymph node metastases was higher than corresponding primary breast cancer. These results suggest that ANXA1 may play a multifaceted role in breast cancer development, progression, and metastases.

The effect of soil organic matter on fate of polycyclic aromatic hydrocarbons in soil: A microcosm study

A microcosm study was conducted to address the influences of air-soil partition and sequestration on the fate of polycyclic aromatic hydrocarbons (PAHs) in soil. Sterilized and unsterilized soils with soil organic carbon (SOC) content ranging from 0.23 to 7.06% were incubated in a chamber with six PAHs supplied through air. After 100 d of incubation when the system approached pseudo-steady state, the PAHs concentrations in the unsterilized soils still correlated with SOC significantly, while the association did not exist for those sterilized. The lower degradation rate in the soil with higher SOC was likely the major reason for the association between SOC and PAHs concentrations, while the decreased surface porosity likely suppressed such correlation for the sterilized samples. The results indicated that the sequestration was likely the major mechanism for the accumulation of PAHs in soils, while both of the soil porosity and PAHs properties had observed influences.

First molecular detection of group A rotaviruses in drinking water sources in Beijing, China

The most prevalent group A rotavirus found in the diarrheic children was also determined in drinking water sources including raw water, treated water and tap water in Beijing, and then the possible contamination contributions to tap water for human consumption were discussed in this study. A total of 26 raw water samples, 77 treated water samples and 143 tap water samples in Beijing were collected for analysis of group A rotavirus from April 2006 to August 2007. According to the results, it was shown that group A rotaviruses occurred in 9 raw water samples (34.6%), 9 treated water samples (11.7%) and 32 tap water samples (22.4%) during the sampling period, and low disinfectant residuals or a vulnerability of the distribution system to pressure transients, in addition to raw water, may account for the group A rotaviruses contamination to tap water. The rotavirus contamination observed in this study may highlight a potential public health risk and illustrate the importance of including routine virological analysis of drinking water supplies during winter time in Beijing.

A directional passive air sampler for monitoring polycyclic aromatic hydrocarbons (PAHs) in air mass

A passive air sampler was developed for collecting polycyclic aromatic hydrocarbons (PAHs) in air mass from various directions. The airflow velocity within the sampler was assessed for its responses to ambient wind speed and direction. The sampler was examined for trapped particles, evaluated quantitatively for influence of airflow velocity and temperature on PAH uptake, examined for PAH uptake kinetics, calibrated against active sampling, and finally tested in the field. The airflow volume passing the sampler was linearly proportional to ambient wind speed and sensitive to wind direction. The uptake rate for an individual PAH was a function of airflow velocity, temperature and the octanol-air partitioning coefficient of the PAH. For all PAHs with more than two rings, the passive sampler operated in a linear uptake phase for three weeks. Different PAH concentrations were obtained in air masses from different directions in the field test.

Effects of diethylhexyl phthalate (DEHP) on INSL3 mRNA expression by Leydig cells derived from mouse embryos and in newborn mice

Insulin-like factor 3 (INSL3) regulates testicular descent during fetal life, and Insl3 gene inactivation results in cryptorchidism. Little is known, however, about whether the plasticizer diethylhexyl phthalate (DEHP), a contaminant found widely in the environment, influences INSL3 expression. In this study, primary cultures of Leydig cells from mouse embryos were treated in vitro with DEHP. We also treated pregnant mice with DEHP from gestation day 12 to postnatal day 3 in order to study the effect of DEHP in vivo. INSL3 mRNA expression levels in primary Leydig cell cultures and in the testes of newborn mice were significantly lower following DEHP treatment. DEHP also caused detrimental morphological changes in both primary cultures of Leydig cells and the testes of newborn mice. These results suggest that the downregulation of INSL3 mRNA by DEHP might cause abnormalities of gubernacular development, which might be one of the mechanisms for development of cryptorchidism.

Production and characterization of monoclonal antibodies to (poly100)S1 protein of avian infectious bronchitis virus

Fragments within S1 genes ((poly100)S1) of infectious bronchitis virus (IBV) strains ZJ971, M41 and SC021202 (SC) were subcloned into a prokaryotic expression vector and expressed in Escherichia coli. Monoclonal antibodies (mAbs) against the recombinant (poly100)S1 proteins were produced, characterized and used to analyse epitopes on the S1 subunit of IBV. Nine mAbs raising from the three (poly100)S1 proteins recognized five different epitopes of the S1 subunit, designated as S1-A, B, C, D and E. Epitopes S1-C and S1-D are common for the three IBV strains, while S1-A and S1-B exist on ZJ971 and M41 strains, and S1-E was a strain-specific epitope for SC strain. Immunocytochemistry indicated that all the mAbs to the (poly100)S1 proteins can react with the homologous S1 glycoprotein expressed in Vero cells. Moreover neutralization test demonstrated that only mAbs 6E2, 4F9 and 6G4 had neutralization activity for the homologous IBV. These mAbs to (poly100)S1 protein were potential candidates for detecting and distinguishing IBV strains, and also used to examine antigenic variation of the S1 protein.

Echinosporins as new cell cycle inhibitors and apoptosis inducers from marine-derived Streptomyces albogriseolus

Bioassay-guided fractionation of the ethyl acetate extract from the fermentation broth of marine-derived Streptomyces albogriseolus A2002 led to the isolation of echinosporin (1) and 7-deoxyechinosporin (2). Compound 1 inhibited the proliferation of tsFT210, K562 and HCT-15 cancer cells (IC(50) 91.5 microM, 25.1 microM and 247 microM respectively) and 2 showed the same effect on K562 cells (IC(50) 143 microM). Flow cytometric analysis suggested that 1 and 2 exert their anti-proliferative effects on those cells through inhibiting cell cycle at the G(2)/M phase and inducing apoptosis.

Pelargonium necrotic spot virus: a new member of the genus Tombusvirus

A virus isolate from Pelargonium spp., provisionally designated UPEV (unknown pelargonium virus), had isometric particles 31-33 nm in diameter, with a granular surface structure similar to that of viruses in three genera of family Tombusviridae. Immunoelectron microscopy proved that UPEV was serologically distinct from all examined morphologically similar members of the family Tombusviridae. The induced cytopathology was characterized by large cytoplasmic virion aggregates and the formation of multivesicular bodies derived from mitochondria. Analysis of the complete ssRNA genome sequence revealed four open reading frames (ORFs) arranged like those of viruses in the genera Tombusvirus and Aureusvirus. Sequence comparisons indicated that three of the four ORFs had a high identity (52-97% identical amino acids) with the respective ORFs of tombusvirus species, especially with Carnation Italian ringspot virus, but not with those of viruses in other genera in Tombusviridae. On the contrary, UPEV coat protein had a low indentity (36-53% identical amino acids) with that of the aureusvirus Pothos latent virus. The data suggested that UPEV originated in a recombination event between a tombus- and an aureusvirus. According to its original host and symptom expression we proposed the new virus be named Pelargonium necrotic spot virus (PeNSV) and classified it as a distinct and new species in the genus Tombusvirus.

Rapid sample preparation method for PCR-based detection of Escherichia coli O157:H7 in ground beef

AIM

To develop an improved, rapid and sensitive sample preparation method for PCR-based detection of Escherichia coli O157:H7 in ground beef.

METHODS AND RESULTS

Fresh ground beef samples were experimentally inoculated with varying concentrations of E. coli O157:H7. PCR inhibitors were removed and bacterial cells were concentrated by filtration and centrifugation, and lysed using enzymatic digestion and successive freeze/thaw cycles. DNA was purified and concentrated via phenol/chloroform extraction and the Shiga toxin 1 gene (stx1) was amplified using PCR to evaluate the sample preparation method. Without prior enrichment of cells in broth media, the detection limit was 103 CFU g-1 beef. When a 6 h enrichment step was incorporated, the detection limit was 1 CFU g-1 beef. The total time required from beginning to end of the procedure was 12 h.

CONCLUSIONS

The sample preparation method developed here enabled substantially improved sensitivity in the PCR-based detection of E. coli O157:H7 in ground beef, as compared to previous reports.

SIGNIFICANCE AND IMPACT OF THE STUDY

Superb sensitivity, coupled with quick turn-around time, relative ease of use and cost-effectiveness, makes this a useful method for detecting E. coli O157:H7 in ground beef.

[Studies of mtDNA haplotype polymorphism of Rongcheng population in China]

The loss of one copy of two 9-bp repeats in mtDNA non-coding region V is often found in Asia and Pacific populations. Two hundred and ten samples from Rongcheng county, Shandong province were detected with the deletion frequency of 12.4%. A distribution map of frequencies of mtDNA 9-bp deletion among Asian and Pacific population was made with reference to other published data. Further discussion was made for the hypotheses of affinity and original model of those populations. PCR-RFLP was conducted to obtain the mtDNA polymorphism information in five other mtDNA regions except the 9-bp deletion in 95 samples. Twenty-seven different mtDNA haplotypes were found, and the relationships among these haplotypes have been analyzed by using MEGA2.0 and PHYLIP 3.57. Two new RFLP sites caused by point mutation were also found, which have not been reported in Chinese populations.

Differential detection of cytomegalovirus immediate-early messenger RNA in clinical samples using ligation-dependent PCR

BACKGROUND

Cytomegalovirus (CMV) causes life-threatening infections in immunocompromised patients, especially those with acquired immunodeficiency or organ transplants. Therefore, early detection of CMV is important to guide the clinical management of actively infected patients. Because detection of replicative transcripts indicates that the virus is in the process of being replicated in the infected cell, we applied a novel, sensitive, ligation-dependent (LD)-PCR method to detect CMV immediate-early (IE) messenger RNA (mRNA), an indicator of viral replication.

METHODS AND RESULTS

Viral mRNAs were released from infected cells by incubation in 5 M guanidinium thiocyanate, and IE mRNAs were captured onto magnetic beads through oligo(dT) capture probes. Two hemiprobes, each containing an IE mRNA-complementary region and a region for PCR primer binding, were captured by binding to the IE mRNA. These hemiprobes, bound on an IE mRNA in juxtaposition to one another, were linked together by a DNA ligase to form a full probe that served as the template for PCR amplification. This approach detected IE mRNAs in CMV-propagating cells, but not in supernatants containing only viral DNAs. Thirty-one clinical specimens were tested by LD-PCR; 18 specimens were positive (ten specimens, bronchoalveolar lavage [BAL]; five specimens, urine; two specimens, blood; one specimen, biopsy), 17 of which were confirmed by culture. Three culture-positive samples (two specimens, urine; one specimen, BAL) were missed by LD-PCR, and one urine sample was positive by LD-PCR but negative by culture.

CONCLUSION

LD-PCR assay is a reliable test for the early diagnosis of active CMV infection in patient specimens.

Detection of rare DNA targets by isothermal ramification amplification

We described previously a novel DNA amplification technique, termed ramification amplification (RAM) (Zhang et al., Gene 211 (1998) 277). This method was designed to utilize a circular probe (C-probe) that is covalently linked by a DNA ligase when it hybridizes to a target. Then, a DNA polymerase extends the bound forward primer along the C-probe and continuously displaces a downstream strand, generating a multimeric single-stranded DNA (ssDNA), analogous to in vivo 'rolling circle' replication of bacteriophage. This multimeric ssDNA then serves as a template for multiple reverse primers to hybridize, extend, and displace downstream DNA, generating a large ramified (branching) DNA complex, and resulting in an exponential amplification. Previously, we were able to achieve a significant amplification using phi29 DNA polymerase that has a high processivity and strong displacement activity. However, due to the intrinsic limitations of the polymerase, we only achieved a sensitivity of 10,000 target molecules, which is insufficient for most practical uses. Therefore, we tested several DNA polymerases and found that exo(-) Bst DNA polymerase meets the requirement for high sensitivity. By further improving the assay condition and format, we are able to detect fewer than ten targets in 1 h and to apply successfully this method for detection of Epstein-Barr virus in human lymphoma specimens.

[Somatic embryogenesis and plant regeneration in vitro from young shoots of Aralia elate (Miq.) Seem]

Explants excised from the young shoots of Aralia elata (Miq.) Seem. were cultured on MS media. Calli were induced from the explants on MS medium supplemented with 0.5 mg/L 2, 4-D, 0.5 mg/L BA and 0.5 mg/L NAA. Then these calli were transferred onto the MS medium containing 2.0 mg/L 2,4-D + 0.5 mg/L BA + 0.5 mg/L NAA and 0.2% activated charcoal. Under these conditions the somatic embryoids were observed and regenerated plants were obtained from somatic embryogenesis. Then, a experimental system with stability and high regenerating efficiency has been set up for the propagation of the young plants, the cell breeding technology and the control of somatic embryogenesis of Aralia elata (Miq.).

Ramification amplification: a novel isothermal DNA amplification method

We have developed a novel isothermal DNA amplification method with an amplification mechanism quite different from conventional PCR. This method uses a specially designed circular probe (C-probe) in which the 3' and 5' ends are brought together in juxtaposition by hybridization to a target. The two ends are then covalently linked by a T4 DNA ligase in a target-dependent manner, producing a closed DNA circle. In the presence of an excess of primers (forward and reverse primers), a DNA polymerase extends the bound forward primer along the C-probe and displaces the downstream strand, generating a multimeric single-stranded DNA (ssDNA), analogous to the "rolling circle" replication of bacteriophages in vivo. This multimeric ssDNA then serves as a template for multiple reverse primers to hybridize, extend, and displace downstream DNA, generating a large ramified (branching) DNA complex. This ramification process continues until all ssDNAs become double-stranded, resulting in an exponential amplification that distinguishes itself from the previously described nonexponential rolling circle amplification. In this report, we prove the principle of ramification amplification. By using a unique bacteriophage DNA polymerase, Ø29 DNA Polymerase, that has an intrinsic high processivity, we are able to achieve significant amplification within 1 hour at 35 degrees C. In addition, we applied this technique for in situ detection of Epstein-Barr viral sequences in Raji cells.

Nonimmune hydrops fetalis and activation of the renin-angiotensin system after asphyxia in preterm fetal sheep

This study examined the hypothesis that the development of hydrops fetalis after asphyxia in the 0.6 gestation sheep fetus would be associated with activation of the fetal renin-angiotensin system (RAS). Fetuses were randomly assigned to either sham occlusion (n = 7) or to 30 min of asphyxia induced by complete umbilical cord occlusion for 30 min (n = 8). Asphyxia led to severe bradycardia and hypotension that resolved after release of occlusion. After occlusion, plasma renin concentration was significantly increased in the asphyxia group compared with controls (P < 0.005) after 3 min (16.3 +/- 5.3 vs. 4.1 +/- 1.3 ng. ml(-1). h(-1)), and 72 h (30.6 +/- 6.3 vs. 3.7 +/- 1.2 ng. ml(-1). h(-1)). Renal renin concentrations and mRNA levels were significantly greater in the asphyxia group after 72 h of recovery. All fetuses in the asphyxia group showed generalized tissue edema, ascites, and pleural effusions after 72 h of recovery. In conclusion, asphyxia in the preterm fetus caused sustained activation of the RAS, which was associated with hydrops fetalis.

Serum hepatitis C virus RNA levels and histologic findings in liver allografts with early recurrent hepatitis C

BACKGROUND

Histopathologic features of early recurrent hepatitis C after orthotopic liver transplantation (OLTx) may be modified by immunosuppressive therapy or complicated by other conditions. Hepatitis C virus (HCV) RNA level usually increases after OLTx, but its correlation to histologic findings is not clear.

OBJECTIVE

To evaluate the histologic findings of early recurrent hepatitis C in liver allografts and its correlation to serum HCV RNA level.

METHODS

We studied 14 patients who underwent OLTx for chronic HCV infection. Thirty liver biopsy specimens and HCV RNA levels of 22 corresponding plasma samples obtained during the first 6 months following OLTx were analyzed. The control group (9 patients, 25 biopsy specimens) was chosen at random from patients with chronic liver disease other than HCV who were undergoing OLTx, and all tested negative for HCV RNA by polymerase chain reaction after OLTx.

RESULTS

Statistically significant pathological features of early recurrent HCV infection were the number of acidophilic bodies, piecemeal necrosis, lymphocyte predominance in the portal tracts, and fibrous septum. These findings and histologic activity index scores increased with time after OLTx. The HCV RNA levels determined by branched DNA assay showed no significant correlation with histologic features. However, patients with higher histologic activity index scores tended to have higher RNA levels.

CONCLUSIONS

Liver biopsy specimens are helpful for the diagnosis or confirmation of early recurrent hepatitis C in liver allografts, but serial biopsy specimens are sometimes required for definite diagnosis. The HCV RNA levels are usually higher in patients who display signs of more severe liver damage.

[Studies on single cell cloning of Ginkgo biloba L]

OBJECTIVE

To investigate the relations of the productivity stability of to the homogenization of Ginkgo biloba cells by single cell clones.

METHOD

Using plant single cell plate culture technique.

RESULTS

Adding 500 ml.L-1L-glutamine in the medium increased greatly the cell plating efficiency (PE), and within the range 0.5-5.0 x 10(4) Cell.ml-1 of the initial cell density, the PE increased with the increment of the cell density. Of the 48 cell clones obtained, the GKB content in G-22 clone reached 0.099%; and most of the clones remain stable in growth and GKB production during subcultures.

CONCLUSION

During the cell and tissue culture of G. biloba, the application of plant single cell cloning technique helps to a certain extent solve the problem of productivity instability of ginkgolide.

[The dynamic measurements of human body's unbalance]

A through study of the postural stability of 40 subjects has been conducted with a stabilometer and the computer system. The subjects stand on the testing platform for 10 seconds and meanwhile the sum of frequency spectrum is being analyzed. The most men subjects maintain a little sway well within timits during the trials. The testing conditions include open eyes, close eyes, 10 degrees, 20 degrees, 30 degrees of platform inclination, transverse vision tracking, longitudinal vision tracking and vectorial vision tracking, All testing results show that there are unbalance differences between different age groups under different conditions.

Intramolecular interaction of yeast TFIIB in transcription control

The general transcription factor TFIIB is a key component in the eukaryotic RNA polymerase II (RNAPII) transcriptional machinery. We have previously shown that a yeast TFIIB mutant (called YR1m4) with four amino acid residues in a species-specific region changed to corresponding human residues affects the expression of genes activated by different activators in vivo. We report here that YR1m4 can interact with several affected activators in vitro. In addition, YR1m4 and other mutants with amino acid alterations within the same region can interact with TATA-binding protein (TBP) and RNAPII normally. However, YR1m4 is defective in supporting activator-independent transcription in assays con-ducted both in vitro and in vivo. We further demonstrate that the interaction between the C-terminal core domain and the N-terminal region is weakened in YR1m4 and other related TFIIB mutants. These results suggest that the intramolecular interaction property of yeast TFIIB plays an important role in transcription regulation in cells.

Effects of placental insufficiency on the ovine fetal renin-angiotensin system

We postulated that chronic placental insufficiency would be associated with reduced expression of renal renin and angiotensinogen genes in the fetal sheep. Placental development was restricted in ewes by removing the majority of caruncles prior to mating (placentally restricted (PR) group). The weights of PR fetuses were significantly reduced (P < 0.05, 2.98 +/- 0.33 kg) compared to control fetuses (4.20 +/- 0.30 kg). Kidney weights were also significantly reduced in the PR fetuses (P < 0.05, 8.4 +/- 0.9 g) compared with control fetuses (12.2 +/- 1.3 g). The ratios of renal renin/-actin mRNA levels were significantly reduced in PR fetuses (P < 0.001, 0.35 +/- 0.02) when compared to control animals (0.98 +/- 0.13). The renal angiotensinogen mRNA/18S rRNA ratio was significantly lower (P < 0.05, 0.28 +/- 0.13) in PR fetuses compared with control fetuses (0.72 +/- 0.10), while hepatic angiotensinogen was unaffected. There was a positive correlation between renal renin mRNA and renal angiotensinogen mRNA levels (r = 0.65, P < 0.05, n = 12). It is unlikely that these changes in renal angiotensinogen and renin mRNA were due to the small increment in plasma cortisol levels (< 5 nmol l-1). There was, however, a positive correlation between arterial PO2 and renal renin mRNA (r2 = 0.77, P < 0.01). Plasma renin levels were not different between the two groups. Thus, restriction of nutrient and oxygen supply throughout fetal life was associated with suppression of renal renin and renal angiotensinogen gene expression, with no effect on hepatic angiotensinogen mRNA levels. This specific suppression of fetal renal renin and angiotensinogen expression could alter the activity of the intrarenal RAS and so affect growth and development of the kidney.

Gestational changes in fetal renal and hepatic angiotensinogen mRNA and protein

The aim of the study was to determine the amount of angiotensinogen expression and its protein product in fetal sheep liver and kidney in the last third of gestation. Angiotensinogen mRNA was measured by RNase protection assay and its protein levels were measured by radioimmunoassay. Levels were measured at 80, 95, 111, 125 and 139 days. Angiotensinogen mRNA was present in all fetal liver and kidney samples tested. The ratio of hepatic angiotensinogen mRNA/18 S rRNA increased by 100% (P < 0.001) and angiotensinogen levels increased by 33% (P < 0.001) in fetal sheep from 80 to 139 d. Over the same period the ratio of renal angiotensinogen mRNA/18 S rRNA increased by 170% (P < 0.001) and renal angiotensinogen protein increased by 41% (P < 0.001). The levels of angiotensinogen mRNA and its protein in the adult kidney were less than in kidneys of 139 d old fetuses (P < 0.01). There was a direct relationship between levels of angiotensinogen mRNA and its protein in the liver (r = 0.53, P < 0.01, n = 25) and in the kidney (r = 0.75, P < 0.0001, n = 24). These findings demonstrate that there is a significant increase in both hepatic and renal angiotensinogen gene expression in the last third of gestation in the fetal sheep and that this increase is associated with an increase of angiotensinogen levels in both tissues. This increase in angiotensinogen in late gestation could influence the activity of both the intrarenal and circulating renin angiotensin systems.

Effects of aortic ligation on the renin angiotensin system in hydronephrotic mice

A model of aortic ligation in mice with a hydronephrotic kidney (absence of macula densa) was used to determine the effects of aortic ligation on the renal renin-angiotensin system (RAS). Blood pressure increased from 83 +/- 2 to 133 +/- 8 mmHg within 7 days after aortic ligation (p < 0.01). Aortic ligation increased plasma renin (p < 0.01); renin (p < 0.05) and renin mRNA levels (p < 0.001) rose in the ischaemic kidney. In mice with a left hydronephrotic kidney without ischaemia, blood pressure did not change significantly. Plasma renin levels from the left renal vein were lower than from the contralateral vein, but renin (p < 0.01) and renin mRNA levels (p < 0.05) in the hydronephrotic kidney were higher than in the contralateral kidney. In mice with hydronephrosis that had an aortic ligature, blood pressure increased from 81 +/- 2 to 135 +/- 6 mmHg (p < 0.01). Plasma renin increased; renin and renin mRNA levels increased significantly in the ischaemic hydronephrotic kidney (p < 0.01), but not in the contralateral kidney. Thus, the presence of the macula densa is critical for renin release but not for renin gene expression. Aortic ligation results in a significant rise in blood pressure and the activity of the RAS. The mechanisms may involve a baroreceptor and/or an unknown factor.

TT virus infection is widespread in the general populations from different geographic regions

By PCR screening, we found an extremely high prevalence of TT virus (TTV) in the general populations from different geographic regions. This suggests that TTV may be a common DNA virus with no clear disease association in humans. TTV genotyping by phylogenetic analysis was also performed.

Human papillomavirus may be common within nasopharyngeal carcinoma of Caucasian Americans: investigation of Epstein-Barr virus and human papillomavirus in eastern and western nasopharyngeal carcinoma using ligation-dependent polymerase chain reaction

BACKGROUND

Nasopharyngeal carcinoma (NPC), particularly those tumors endemic to the Far East, commonly harbor Epstein-Barr virus (EBV), thought to serve as an important oncogenic promoter. Human papillomavirus (HPV) is associated with a proportion of upper aerodigestive tract carcinomas. We hypothesized that HPV might also contribute to the pathogenesis of NPC, and we queried whether geographic and racial distinctions may be identified between NPC of the Far East versus those diagnosed in Caucasian American patients with regard to the interrelationship of histologic subtype and viral infection.

MATERIALS AND METHODS

Formalin-fixed paraffin-embedded tissue (FFPET) from 30 patients (6 Caucasian Americans, 1 Chinese American, 14 and 9 patients from Korea and China, respectively) were studied using the ligation-dependent polymerase chain reaction (LD-PCR). These cases were histologically classified according to the World Health Organization (WHO) schema for NPC. Consensus target probes complementary to the L1 region of over 30 HPV types, as well as target probes complementary to EBER-1 (EBV-related nontranslated latency-associated RNA), were used to amplify target sequences.

RESULTS

Seven of 30 NPC (23%) contained HPV sequences. There were 6 Caucasian American patients with NPC; 3 cases (50%) were HPV positive (HPV+). Two of these Caucasian Americans had WHO type I tumors: one was HPV+ and EBV negative (EBV-) and the other was HPV-/EBV+. The remaining Caucasian American NPCs were WHO-II/III tumors which tested as follows: two were coinfected with HPV and EBV, the other two contained EBER but not HPV sequences. The single Oriental American patient had a WHO-III NPC which was HPV-/EBV+. Of the Eastern NPC patients, 4 (1 WHO-I, 3 WHO-II/III) of 23 (17%) NPCs contained HPV sequences as well as EBV. Conclusion. Human papillomavirus appears to be uncommonly (17%) associated with NPC in patients from the Far East and was detected more often (50%) in NPC from American Caucasian patients. Some of these tumors conformed to our perceptions and expectations of NPC (eg, WHO-I tumors being EBV-/HPV+ and WHO-III tumors being EBV+/HPV-), but other tumors did not conform to these expectations (eg, WHO-III NPC occasionally harboring both HPV and EBV). There appears to be a broad profile in the relationship between HPV, EBV, and NPC histologic subtype. Unfortunately, the number of American Caucasian cases studied are too small to allow for strong conclusions.

Sexual Reproduction and Stable Coexistence of Identical Competitors

Current competition theory predicts that species must be ecologically distinct in order to stably coexist in the same community. This prediction is based on the implicit assumption that the consequences of sexual reproduction can be ignored. If anything, it is generally assumed that sex will only add problems, such as failure of insemination and inbreeding depression to species that have become rare, thus hastening competitive exclusion. Here we suggest that sexual reproduction may also bring rare species advantages in terms of the rate of per capita population growth. The key to our argument is that species-specific density dependence in population growth can occur when sexual reproduction is explicitly considered. We show that density-dependent sex ratio, sexual conflict, and sexually transmitted diseases can all promote species coexistence without separate niches.Copyright 1998 Academic Press

Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group

Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system. While its etiology is not well understood, genetic factors are clearly involved. Until recently, most genetic studies in MS have been association studies using the case-control design testing specific candidate genes and studying only sporadic cases. The only consistently replicated finding has been an association with the HLA-DR2 allele within the major histocompatibility complex (MHC) on chromosome 6. Using the genetic linkage design, however, evidence for and against linkage of the MHC to MS has been found, fostering suggestions that sporadic and familial MS have different etiologies. Most recently, two of four genomic screens demonstrated linkage to the MHC, although specific allelic associations were not tested. Here, a dataset of 98 multiplex families was studied to test for an association to the HLA-DR2 allele in familial MS and to determine if genetic linkage to the MHC was due solely to such an association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta) in the MHC demonstrated strong genetic linkage (parametric lod scores of 4.60, 2.20 and 1.24, respectively) and a specific association with the HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results by HLA-DR2 status showed that the linkage results were limited to families segregating HLA-DR2 alleles. These results demonstrate that genetic linkage to the MHC can be explained by the HLA-DR2 allelic association. They also indicate that sporadic and familial MS share a common genetic susceptibility. In addition, preliminary calculations suggest that the MHC explains between 17 and 62% of the genetic etiology of MS. This heterogeneity is also supported by the minority of families showing no linkage or association with loci within the MHC.

Evolutionarily Stable Reproductive Strategies in Sexual Organisms. Part V-Joint Effects of Parent-offspring Conflict and Sibling Conflict in Perennial Plants

We develop a general treatment of the joint effects of parent-offspring conflict (conflict between broods) and sibling conflict (conflict within broods) in perennial plants. Parent-offspring conflict as well as sibling conflict are examined in the context of an integrated analysis of reproductive allocation, sex allocation, and the amount of resources invested in each offspring. We find that under a wide range of conditions the selected seed size is independent of reproductive effort or sex allocation. To the extent that the relationships between gamete output and resource investment are linear for both sex functions, the separate treatment of reproductive effort, sex allocation, and offspring size-number compromise in modern life-history theories is well justified, regardless of which side, parents or offspring, controls the allocation to individual seed offspring. We show that incorporation of sibling conflict results in even larger seed size, which in turn leads to even lower reproductive effort, than under pure parent-offspring conflict. If the costs of increased provisioning of selfish offspring are entirely borne by their brood mates, then offspring are selected to solicit parental care as long as they continue to benefit individually from more resources.Copyright 1998 Academic Press Limited

Further study of hepatitis C virus RNA detection in formalin-fixed, paraffin-embedded liver tissues by ligation-dependent polymerase chain reaction

Ligation-dependent polymerase chain reaction (LD-PCR) is a novel, simple and sensitive PCR assay that could be useful for the molecular diagnosis of various viral infections. This assay uses two capture probes for RNA isolation and two hemiprobes for the subsequent PCR. To investigate its usefulness in the field of pathological diagnosis, further study of this new PCR technology to detect hepatitis C virus (HCV) RNA was carried out in formalin-fixed, paraffin-embedded (FFPE) liver tissues and the results compared with those obtained by the reverse transcription (RT)-PCR method. We analyzed routinely processed FFPE liver specimens of surgical origin from 13 anti-HCV-seropositive Japanese patients with hepatocellular carcinoma (HCC). As a result, HCV-RNA was detected in FFPE liver specimens in 12 of the tested patients (92.3%) by the LD-PCR method without the use of reverse transcription. In contrast, HCV-RNA was detectable in eight out of 13 cases (61.5%) by the RT-PCR method. These results indicated that LD-PCR was useful for HCV-RNA detection in routinely processed FFPE liver specimens.

Evolutionarily Stable Reproductive Strategies in Sexual Organisms: IV. Parent-Offspring Conflict and Selection of Seed Size in Perennial Plants

The provisioning of offspring in sexually reproducing organisms provides an arena in which genetic conflict of interests between parents and their offspring may be expressed. While most existing models of parent-offspring-conflict consider the case of a parent that rears one offspring a year, this paper is concerned with perennial plants that produce many seeds at one time. Parent-offspring conflict is examined in the context of an integrated analysis of reproductive allocation, sex allocation, and the amount of resources invested in each offspring. I derive the evolutionarily stable strategy (ESS) results for the allocation of resources when the mother plant is in control as well as when the offspring are in control taking into account both density-independent and density-dependent population growth. To the extent that the relationships between gamete output and resource investment are linear for both sex functions, the separate treatment of reproductive effort, sex allocation, and offspring size-number compromise in modern life-history theories is justified, regardless of which side, parents or offspring, wins the conflict. In such cases, the ESS sex allocation is exactly what is found in traditional sex allocation theory, and the ESS reproductive effort maximizes the rate of population growth in density-independent populations, or the amount of resources allocated to reproduction during an average lifespan in density-dependent populations. In contrast to the previous theoretical conclusions based on the analyses of single-offspring cases, the ESS reproductive effort under the offspring's control of allocation to individual offspring is found to be lower than that when mothers are in control. This paradoxical result occurs because a mother producing fewer ovules fares better if she knows that each of her seed offspring will get more resources than the amount she is selected to give. The evolutionarily stable offspring size in both density-independent and density-dependent populations does not depend on mother's reproductive effort and investment-independent mortality, just as traditional models of offspring size-number trade-offs would predict.Copyright 1998 Academic Press Limited

Amplification of target-specific, ligation-dependent circular probe

We describe a novel polymerase chain reaction (PCR)-based gene amplification method utilizing a circularizable oligodeoxyribonucleotide probe (C-probe). The C-probe contains two target complementary regions located at each terminus and an interposed generic PCR primer binding region. The hybridization of C-probe to a target brings two termini in direct apposition as the complementary regions of C-probe wind around the target to form a double helix. Subsequent ligation of the two termini results in a covalently linked C-probe that becomes 'locked on to' the target. The circular nature of the C-probe allows for the generation of a multimeric single-stranded DNA (ssDNA) via extension of the antisense primer by Taq DNA polymerase along the C-probe and displacement of downstream strand, analogous to 'rolling circle' replication of bacteriophage in vivo. This multimeric ssDNA then serves as a template for multiple sense primers to hybridize, extend, and displace downstream DNA, generating a large ramified (branching) DNA complex. Subsequent thermocycling denatures the dsDNA and initiates the next round of primer extension and ramification. This model results in significantly improved amplification kinetics (super-exponential) as compared to conventional PCR. Our results show that the C-probe was 1000 times more sensitive than the corresponding linear hemiprobes for detecting Epstein-Barr virus early RNA. The C-probe not only increases the power of amplification but also offers a means for decontaminating carryover amplicons. As the ligated C-probes possess no free termini, they are resistant to exonuclease digestion, whereas contaminated linear amplicons are susceptible to digestion. Treatment of the ligation reaction mixture with exonuclease prior to amplification eliminated the amplicon contaminant, which could also have been co-amplified with the same PCR primers; only the ligated C-probes were amplified. The combined advantages of the C-probe and thermocycling have a broad applicability for the detection of both DNA and RNA. Finally, we described a novel isothermal amplification method, ramification extension amplification, utilizing circular nature of C-probe and displacement activity of DNA polymerase.

Clinical and molecular pathology of aggressive Schneiderian papilloma involving the temporal bone

BACKGROUND

Inverting papilloma is a benign but locally aggressive sinonasal tumor that rarely involves the middle ear or temporal bone.

METHODS

A report of a case and the molecular pathology of the tumor is presented.

RESULTS

A 35-year-old woman with a history of recurrent inverting papilloma of the left paranasal sinuses was found to have evidence of extension through the eustachian tube and extensive involvement of the temporal bone. Surgical management resulted in the patient being disease-free at 14 months. Molecular pathology studies of the resected tumor suggest an association with human papillomavirus.

CONCLUSIONS

Direct extension of the sinonasal tumor through the eustachian tube may represent the pathologic mechanism involved in the development of inverting papilloma involving the middle ear and temporal bone.

Evolutionarily Stable Reproductive Strategies in Sexual Organisms: III. The Effects of Lottery Density Dependence and Pollen Limitation

This paper extends our previous work on modelling, within a single framework, the allocation of resources to reproduction vs. survival and the male vs. female components of reproduction in perennial plants. We derive the evolutionarily stable strategy (ESS) results under pollen limitation for both hermaphroditic and dioecious plant populations held stable through density-dependent juvenile recruitment. Pollen limitation affects female reproductive allocation in our model because there is post-flowering provisioning of offspring. We find that pollen limitation is unimportant to the ESS reproductive allocation and sex allocation so long as there are enough seeds to fill the empty sites left by the death of adults. To the extent that the relationships between gamete output and resource investment are linear for both sexes or sex functions, the separate treatment of reproductive and sex allocation in modern life-history and sex-allocation theories is adequate. In such cases, the ESS sex allocation is exactly what is found in traditional sex allocation theory, and the ESS reproductive allocation of hermaphrodites or females in a dioecious species maximizes the amount of resources allocated to reproduction during an average lifespan, an analogue of the usual maximization principle in life-history theory modified to include the possibility of pollen limitation and extended seed maturation. The ESS reproductive allocation of males in a dioecious species maximizes lifetime pollen production, independent of pollen limitation and the female's resource allocation. Copyright 1997 Academic Press Limited

Detection of hepatitis C virus RNA using ligation-dependent polymerase chain reaction in formalin-fixed, paraffin-embedded liver tissues

Reverse transcription polymerase chain reaction (RT-PCR) has been used to detect hepatitis C virus (HCV) sequences in liver tissue. However, RT-PCR has a variable detection sensitivity, especially on routinely processed formalin-fixed, paraffin-embedded (FFPE) specimens. RNA-RNA and RNA-protein cross-links formed during formalin fixation is the major limiting factor preventing reverse trans criptase from extending the primers. To overcome this problem, we applied the ligation-dependent PCR (LD-PCR) for the detection of HCV RNA in FFPE liver tissue. This method uses two capture probes for RNA isolation and two hemiprobes for the subsequent PCR. Despite cross-links, the capture probes and the hemiprobes are able to form hybrids with HCV RNAs released from the FFPE tissue. The hybrids are isolated through binding of the capture probes to paramagnetic beads. The hemiprobes are then ligated by a T4 DNA ligase to form a full probe that serves as a template for the Taq DNA polymerase. A total of 22 FFPE liver specimens, 21 with hepatocellular carcinoma (HCC) and 1 with biliary cirrhosis secondary to bile duct atresia were selected for this study, of which 13 patients were HCV seropositive and 9 seronegative. HCV RNA was detectable by ID-PCR from all 13 HCV-seropositive HCCs and from 5 of 8 HCV-seronegative HCCs but not from the HCV-seronegative liver with biliary atresia. By contrast, RT-PCR detected HCV sequences in only 5 of the HCV-sero-positive and in 1 of the HCV-seronegative HCCs. To resolve the discordance between the LD-PCR and RT-PCR results, RT-PCR was performed on frozen liver tissue of the discrepant specimens, which confirmed the LD-PCR positive results. In conclusion, LD-PCR is a more sensitive method than RT-PCR for the detection of HCV sequences in routinely processed liver tissues. A high rate of HCV infection (86%) is found in HCC specimens, indicating a previously underestimated role of HCV in HCC pathogenesis.

Changes in renal renin gene expression in fetal sheep

1. Renin gene expression was investigated in kidneys from 13 foetal and four adult sheep. 2. The levels of renal renin mRNA in foetuses were greater than those in adult sheep (P < 0.001). 3. There was no significant difference in renin mRNA levels between foetuses aged 91 and 134 days (term 150 days). 4. The levels of renin gene expression were higher (178 +/- 5 units; P < 0.001) in foetuses at 142 days than levels in 91 (144 +/- 4 units) and 134 days old foetuses (146 +/- 6 units). 5. It is concluded that the high level of renin gene expression in the foetal kidney is responsible for the high levels of renin in the foetal circulation.

Novel, ligation-dependent PCR assay for detection of hepatitis C in serum

A simple, sensitive, and specific ligation-dependent PCR (LD-PCR) method for the detection of hepatitis C virus (HCV) RNA in serum is described. The assay uses two DNA capture probes for RNA isolation and two DNA hemiprobes for subsequent PCR. Each capture probe has a 3' sequence complementary to the conserved 5' untranslated region of HCV RNA and a biotin moiety at the 5' end capable of interacting with streptavidin-coated paramagnetic beads. Each hemiprobe contains a sequence complementary to the 5' untranslated region in juxtaposition to one another and a common sequence for PCR primer binding. In guanidinium thiocyanate solutions, the capture probes and the hemiprobes form a hybrid with their target, and the hybrid can be isolated from serum by the binding of the capture probes to the paramagnetic beads in the presence of a magnetic field. The hemiprobes can then be linked to each other by incubation with T4 DNA ligase to form a full probe that serves as a template for a PCR. When serial 10-fold dilutions of synthetic HCV RNA (10(7) to 10 molecules) were tested, there was a good correlation between the amount of PCR product and the initial number of RNA molecules, with a sensitivity of 100 HCV RNA molecules per reaction. Twenty-four specimens that had been tested by either a branched DNA probe (bDNA) assay (13 specimens) or a reverse transcription PCR (RT-PCR) assay (11 specimens) were also analyzed by LD-PCR. The results showed a good correlation among LD-PCR, RT-PCR, and the bDNA assay. However, both LD-PCR and RT-PCR were more sensitive than the bDNA assay when the HCV titer was low.

Identification of Haynaldia villosa chromosomes added to wheat using a sequential C-banding and genomic in situ hybridization technique

Genomic in situ hybridization (GISH) offers a convenient and effective method for cytological detection, but can not determine the identity of the chromosomes involved. We integrated C-banding with GISH to identify Haynaldia villosa chromosomes in a wheat background. All chromosomes of H. villosa showed C-bands, either in telomeric regions or in both telomeric and centromeric regions, which allowed unequivocal identification of each H. villosa chromosome. The seven pairs of H. villosa chromosomes were differentiated as 1-7 according to their characteristic C-bands. Using a sequential C-banding and GISH technique, we have analyzed somatic cells of F3 plants from the amphiploid Triticum aestivum-H. villosa x 'Yangmai 158' hybrids. Three plants (94009/5-4,94009/5-8 and 94009/5-9) were shown to contain H. villosa chromosome(s). 94009/5-4 (2n = 45) had three H. villosa chromosomes (2, 3 and 4); 94009/5-8 (2n = 45) possessed one chromosome 4 and a pair of chromosome 5, and 94009/5-9 (2n = 43) was found to have one chromosome 6 of H. villosa. The combination of GISH with C-banding described here provides a direct comparison of the cytological and molecular landmarks. Such a technique is particularly useful for identifying and localizing alien chromatin and DNA sequences in plants.

Haemophilus parainfluenzae biliary tract infection: rationale for an ascending route of infection from the gastrointestinal tract

Haemophilus parainfluenzae was isolated from a bile specimen of a 56-year-old patient with elevated liver enzymes and chronic cholecystitis. Several factors contributing to nonbacteremic H. parainfluenzae infection of the biliary tract include (i) the not infrequent occurrence of H. parainfluenzae in stool specimens, (ii) the presence of an outer membrane protein similar to those found in enteric bacteria which facilitates adherence to the colonic mucosa, and (iii) an adequate supply of V factor (nicotinamide adenine dinucleotide) supplied from bile and the local flora, which is necessary for H. parainfluenzae's growth. Because H. parainfluenzae rarely occurs in the biliary tract, direct cultivation of bile specimens on chocolate agar seems unwarranted. However, bile specimens showing a gram-negative coccobacillus on a Gram-stained smear that fails to grow on routine media should be subcultured on chocolate agar.

Regression of LNCaP human prostate tumor xenografts in athymic nude mice by 13-cis-retinoic acid and androgen ablation

The present study was designed to investigate the effects of 13-cis-retinoic acid (13-cis-RA) (100 micrograms/mouse/day) and androgen ablation (castration) alone and in combination on growth of a human prostatic carcinoma line (LNCaP) transplanted to athymic nude mice as an experimental model. The results of these studies suggest that; (1) androgen ablation (castration) significantly decreased the size of LNCaP xenograft as compared to untreated animals; (2) when 13-cis-RA was administered to nude mice carrying established tumors (0.51 +/- 0.04 cm3), the tumor size was significantly reduced as compared to untreated controls (0.65 +/- 0.06 cm3 versus 1.63 +/- 0.12 cm3). About 50% of the animals in this group showed xenografts necrosis followed by complete regression of tumors by five months; (3) the combination of androgen ablation and 13-cis-RA treatment to nude mice carrying tumors showed synergistic effect in decreasing the tumor size. These results indicate that combination therapies based on androgen ablation and retinoid administration may be a useful approach for the treatment of prostate cancer.

Transthoracic fine-needle aspiration biopsy cytology of pulmonary neoplasms

The experience with 212 transthoracic fine-needle aspiration biopsy cytology specimens of mass lesions of the lung at a small Canadian hospital is reviewed. The technique showed a sensitivity of 78.0%, a specificity of 85.7%, a positive predictive value of 98.5%, and a negative predictive value of 25.0% when the cytological diagnoses were compared with the final clinicopathological diagnoses listed in the patients' charts. There was only one false positive diagnosis of malignancy. Diagnoses based on cytology of the aspirates were compared with histological diagnoses in 127 cases and the accuracy of typing of the major groups of carcinoma was assessed. Distinction between small-cell carcinoma and non-small-cell carcinoma was usually accurate and fairly good correlation was achieved for all major types of carcinoma. The results for typing of the neoplasm are not as good as those from larger centres in the world. The technique is considered to be useful even in the setting of a small hospital.

[Changes in soluble interleukin-2 receptor and its significance in nephrotic syndrome]

Serum and urine soluble interleukin-2 receptor (SIL-2R) levels were determined with ELISA method in 36 cases of nephrotic syndrome in order to investigate the significance of the change of SIL-2R level. The results showed the values in nephrotic stage group (n = 22) exceeded those in nephrotic stage remission group (n = 14, P < 0.01) and those in healthy controls (n = 20, P < 0.01). However, there was no difference of SIL-2R values either in serum or urine between nephrotic stage remission group and healthy controls (P > 0.05). Serum SIL-2R values were correlated with those of serum creatinine (r = 0.44, P < 0.01) and urine SIL-2R values were correlated with those of urine protein excretion (r = 0.48, P < 0.01). The study suggests that increased concentration of SIL-2R can serve as an indicator of nephrotic syndrome activation and/or exacerbation of renal dysfunction.

Is heterozygous advantage necessary for polymorphism in one-locus two-allele systems?

This paper presents a model of density-dependent selection in a continuously reproducing diploid population with two alleles at one locus. Using differential equations, we assume that the fertility of a mating pair is determined exclusively by the female. Genotypic fitness is defined as the average contribution of an individual of the genotype to the total population growth rate. The conditions for protected polymorphism are derived, and the most interesting new result is that genetic polymorphism does not necessarily require heterozygote superiority in fitness in diallelic one-locus systems if both fertility and viability selection are simultaneously operating in the population.

Basic mycology underscoring medically important fungi

This article details the basic mycologic features of yeast and mold-like fungi causing infections in humans. Concordant with the mycologic attributes delineating species identification, the pathogenic potential of mycotic agents is discussed with particular reference to intrinsic fungal virulence factors (e.g., exoenzymes) and host factors (e.g., neutrophil function, underlying disease) predisposing to colonization and infection.

[Nephrocalcinosis and clinical significance in early chronic renal disease]

Kidney tissue calcium content from 33 diagnostic human renal biopsies was measured to assess tissue calcium concentration early in the course of human renal disease. Renal calcium content was correlated significantly with serum creatinine (r = 0.71, P < 0.001), serum phosphate (r = 0.64, P < 0.001), and serum Ca x P product (r = 0.66, P < 0.001), but not with serum calcium (r = -0.17, P > 0.05). Threefold greater calcium content was measured in biopsied tissue than in normal renal tissue (315 +/- 169 vs 69 +/- 17 mg/kg renal tissue, P < 0.001). The mean level of serum phosphate and Ca x P product was higher in the patients with significant renal function impairment (Ser > 115 mumol/L) than in patients with normal renal function (1.76 +/- 0.33 mmol/L vs 1.29 +/- 0.18 mmol/L, P < 0.001; 43 +/- 4.7 vs 33 +/- 4.5 mmol 2/L2, P < 0.001, respectively). The mean serum calcium levels were not different in the two groups (1.97 +/- 0.24 mmol/L vs 2.07 +/- 0.16 mmol/L, P > 0.05). The results suggest that renal calcium deposition begins early in the course of various renal diseases, and hence may accelerate progression of chronic renal failure the severity of renal calcium deposition is correlated with hyperphosphatemia and with the level of renal impairment. Dietary phosphate restriction may be necessary early in the course of renal disease.