[Relationship between microsatellite instability and hepatocyte growth factor expression and their prognostic significance in colorectal cancer].

OBJECTIVE: To investigate the expression of hepatocyte growth factor (HGF) and its relationship with microsatellite instability (MSI) and their influence on survival in patients with colorectal cancer. METHODS: Immunohistochemistry (IHC) was used to detect the expression of HGF and MSI in 98 specimens of colorectal cancer. Tumors lacking protein expression of any of the four mismatch repair genes (MLH1, PMS2, MSH2 or MSH6) were labelled as MSI, and the rest were considered as microsatellite stable (MSS). The associations between expression and clinicopathological factors were assessed using Chi-square tests. Kaplan-Meier curves, log-rank test, and Cox regression were used to analyze the association between biomarker expressions and overall survival. RESULTS: The incidence rate of MSI in 98 colorectal specimens was 32.7%, and was statistically significantly correlated with the location of tumor and differentiation degree (P<0.05). The HGF-expression rate was 71.4%. The patients with an MSI tumor had a significantly higher HGF expression, compared with the patients with an MSS tumor (P=0.048). The 5-year survival rate of MSI group and MSS group were 39.8% and 58.7%, respectively (P=0.009). The 5-year survival rate of HGF-positive group and HGF-negative group were 46.2% and 67.9% (P=0.035). The multivariate analysis showed that lymphocytic infiltration, TMN stage, MSI and HGF are independent prognostic factors in colorectal cancer (P<0.05 for all). CONCLUSIONS: HGF is highly expressed in colorectal cancer patients with microsatellite instability. Both microsatellite instability and HGF are independent factors affecting the prognosis in patient with colorectal cancer.

Molecular cloning and expression profile of an ATP-binding cassette (ABC) transporter gene from the hemipteran insect Nilaparvata lugens.

The ATP-binding cassette (ABC) transporters belong to a large superfamily of proteins that have important physiological functions in all living organisms. In insects, ABC transporters have important functions in the transport of molecules, and are also involved in insecticide resistance, metabolism, and development. In this study, the Nilaparvata lugens Stal (Hemiptera: Delphacidae) ABCG (NlABCG) gene was identified and characterized. The complete mRNA sequence of NlABCG was 2608-bp long, with an open reading frame of 2064 bp encoding a protein comprised of 687 amino acids. The conserved regions include three N-glycosylation and 34 phosphorylation sites, as well as seven transmembrane domains. The amino acid identity with the closely related species Acyrthosiphon pisum was 42.8%. Developmental expression analysis using quantitative real-time reverse transcriptase PCR suggested that the NlABCG transcript was expressed at all developmental stages of N. lugens. The lowest expression of NlABCG was in the 1st instar, and levels increased with larval growth. The transcript profiles of NlABCG were analyzed in various tissues from a 5th instar nymph, and the highest expression was observed in the midgut. These results suggest that the sequence, characteristics, and expression of NlABCG are highly conserved, and basic information is provided for its functional analysis.

Can abundant colloid exclude oncocytic (Hürthle cell) carcinoma in thyroid fine needle aspiration? Cytohistological correlation of 127 oncocytic (Hürthle cell) lesions.

OBJECTIVE: The objective of the present study was to find out whether the presence or absence of certain cytological features can exclude oncocytic (Hürthle cell) carcinoma in thyroid fine needle aspiration (FNA) to minimize unnecessary surgery. METHODS: Over a 17-year period, 127 hypercellular, oncocyte-exclusive, lymphocyte-absent aspirates obtained via ultrasound-guided FNA with on-site assessment had histology slides for review. The presence or absence of six cytological features (microfollicular arrangement, discohesive single cells, small cell dysplasia, large cell dysplasia, transgressing blood vessels and colloid) and one histological feature (macrofollicular component) were determined for each case independently by two cytopathologists. RESULTS: Histology showed 12 (9.4%) cases of Hashimoto thyroiditis, 23 (18.1%) oncocytic adenomatoid nodules in nodular goitre, 66 (52.0%) oncocytic adenomas and 26 (20.5%) oncocytic carcinomas (13 minimally invasive without angioinvasion, six minimally invasive with angioinvasion, seven widely invasive). Histologically, a macrofollicular component was present in seven of 26 (26.9%) oncocytic carcinomas, including one case with abundant thin colloid. A microfollicular arrangement, discohesive single cells, small cell dysplasia, large cell dysplasia and transgressing vessels were present in oncocytic carcinoma, oncocytic adenoma and oncocytic adenomatoid nodules in nodular goitre. CONCLUSIONS: A macrofollicular component is frequently present in oncocytic carcinoma, oncocytic adenoma and oncocytic adenomatoid nodules in nodular goitre. None of the cytological features studied, including abundant colloid, can exclude oncocytic carcinoma. Oncocytic carcinoma can only be excluded by thorough histological examination of thyroidectomy specimens. A molecular marker is needed to triage oncocytic lesions in thyroid FNA.

Detection of medullary thyroid microcarcinoma using ultrasound-guided fine needle aspiration cytology.

OBJECTIVE: Compared with incidental papillary thyroid microcarcinoma (microPTC), incidental medullary thyroid microcarcinoma (microMTC) is clinically more significant. The objective of the present study was to summarize our experience in detecting microMTCs. METHODS: From 1995 to 2011, there were 10825 thyroid fine needle aspirates (FNAs) guided using high-resolution ultrasound with on-site preparation and evaluation by a cytopathologist. Of the 140 microcarcinomas detected, 132 were microPTCs and eight were microMTCs, which are the subject of the present study. RESULTS: All eight cases were incidentalomas and none of the five women and three men, age 37-70 years, had a family history of MTC. One patient had two FNAs at an interval of 10 months, two had a single lymph node metastasis and one had a 0.1-cm tumour nodule near the main tumour. Four of five plasmacytoid cell microMCTs had irregular borders; two round cell and one rectangular cell tumours had smooth borders. In contrast, 17 larger MTCs diagnosed in the same period included seven plasmacytoid, four giant cell and six spindle cell types. All five plasmacytoid microMTCs were correctly diagnosed on FNA, but the round cell and rectangular cell tumours were undercalled as follicular lesions. Sampling of colloid from adjacent follicles was noted in microMTCs. Two were diagnosed on histology following recommended surgery and one was diagnosed on recommended repeat FNA. CONCLUSIONS: US-guided FNA of thyroid lesions is a powerful tool in the detection of microMTCs, provided that cytopathologists are alerted to the pitfalls described in the present study.

Mapping and fine mapping of quantitative trait loci for the number of vertebrae in a White Duroc × Chinese Erhualian intercross resource population.

The number of vertebrae is associated with body size and meat production in pigs. To identify quantitative trait loci (QTL) for the number of vertebrae, phenotypic values were measured in 1029 individuals from a White Duroc × Chinese Erhualian intercross F(2) population. A whole genome scan was performed with 194 microsatellite markers in the F(2) population. Four genome-wide significant QTL and eight chromosome-wide significant QTL for the number of vertebrae were identified on pig chromosomes (SSC) 1, 2, 6, 7, 10 and 12. The most significant QTL was detected on SSC7 with a confidence interval of 1 cM, explaining 42.32% of the phenotypic variance in the thoracic vertebral number. The significant QTL on SSC1, 2 and 7 confirmed previous reports. A panel of 276 animals representing seven Western and Chinese breeds was genotyped with 34 microsatellite markers in the SSC7 QTL region. No obvious selective sweep effect was observed in the tested breeds, indicating that intensive selection for enlarged body size in Western commercial breeds did not wipe out the genetic variability in the QTL region. The Q alleles for increased vertebral number originated from both Chinese Erhualian and White Duroc founder animals. A haplotype block of approximately 900 kb was found to be shared by all Q-bearing chromosomes of F(1) sires except for one distinct Q chromosome. The critical region harbours the newly reported VRTN gene associated with vertebral number. Further investigations are required to confirm whether VRTN or two other positional candidate genes, PROX2 and FOS, cause the QTL effect.

Depolymerization of microtubules increases the motional freedom of molecular probes in cellular plasma membranes.

Depolymerization of microtubules resulted in an increase in the motional freedom of molecular probes in the plasma membranes of Chinese hamster ovary cells expressed by the order parameter, S, measured with two different lipid-soluble spin label probes, 5-doxyl stearic acid and 16-doxyl methylstearate. Treatment with a variety of microtubule-depolymerizing agents, including Colcemid, colchicine, vinblastine, podophyllotoxin, and griseofulvin, all had similar effects on motional freedom of the probes whereas beta-lumicolchicine was inactive. Several independent lines of evidence suggest that these changes in motional freedom of the probes were not the direct result of the interaction of these relatively hydrophobic drugs with the plasma membrane: the effects of the drugs were not immediate; the dose response of the Colcemid effect was the same as the dose response for depolymerization of microtubules; taxol, which stabilizes microtubules but does not affect motional freedom in the membranes, blocked the effect of Colcemid on motional freedom; a mutant cell line which is resistant to colchicine because of reduced uptake of the drug showed no effects of colchicine on probe motional freedom; and a Colcemid-resistant mutant cell line with an altered beta-tubulin showed no effect of Colcemid on motional freedom in the membrane. These results support the hypothesis that microtubules might affect, directly or indirectly, plasma membrane functions.

Proliferation of esophageal epithelial cells among residents of Linxian, People's Republic of China.

Histopathologic and tritiated thymidine labeling subjects were carried out on esophageal biopsy specimens of 44 human subjects with cytologic evidence of dysplasia from Linxian, People's Republic of China, a high-risk area for esophageal cancer. With the use of histopathologic criteria, 10 cases showed evidence of dysplasia, 20 hyperplasia, and 14 a near-normal morphology when compared with 21 normal cases studied previously from Jiaoxian, a low-risk area for esophageal cancer in the People's Republic of China. Significantly increased labeling indices were found in the esophageal mucosa of the dysplasia and hyperplasia subjects. There was a gradient of increased expansion in the basal layer of proliferating cells progressing from normal to hyperplasia to dysplasia, with the expansion twice as high in the epithelial cell lining in dysplasia when compared with the findings in the normal and near-normal groups. The correlation of proliferative abnormalities with the severity of precancerous lesions of the esophagus indicates that labeling studies may provide a sensitive adjunct to evaluate risk status and any modifications that might result from nutritional intervention.

Treatment of nanosized TiO2-containing wastewater by simultaneous electrocoagulation/electrofiltration.

In this work, a simultaneous electrocoagulation/electrofiltration (EC/EF) treatment module was employed to treat nanosized TiO2-containing wastewater. Nanosized TiO2-containing wastewater was obtained and treated by a self-designed EC/EF treatment module. To evaluate the performance of this novel treatment module, the effects of electric field strength (EFS), transmembrane pressure (TMP), and crossflow velocity (CV) on permeate qualities were investigated. Permeate qualities of concern included pH, turbidity, conductivity, chemical oxygen demand (COD), and total organic carbon (TOC). A full factorial design of experiments was adopted in this work. First, by keeping TMP and CV constant the effects of EFS on permeate qualities were studied. In this set of testing, it was noticed that an application of electric field greatly increased the filtration rate, which was further influenced by the magnitude of EFS. In all cases, the filtration rate decreased as the treatment time elapsed due mainly to fouling of the membrane. Further tests were conducted to study the effects of TMP on permeate qualities by keeping EFS and CV constant. Finally, the effects of CV on permeate qualities were studied by keeping EFS and TMP constant. It was found that the optimal operating conditions would be electric field strength of 166.7 V/cm, transmembrane pressure of 1 kgf/cm2, and crossflow velocity of 0.22cm/s. Under such conditions, permeate would have the following qualities: (1) pH, 6.32; (2) turbidity, 2.41 NTU; (3) conductivity, 15.11 microS/cm; (4) COD, 100.0 mg/L; and (5) TOC, 512.6 mg/L.

An in vitro and in vivo investigation of the phototoxic effect and its amelioration with radioprotective compounds.

Electron spin resonance spectroscopy has been used to demonstrate that the phototoxic antimalarial drug, 6,8-dichloro-2-phenyl-a-2-piperidnylquinolinemethanol (WR 7930), when irradiated with long-wave ultraviolet (UV) light (lambda greater than 320 nm) while held in a glassy matrix at 73 degrees K, enters a triplet state and releases hydrogen atoms in its environment. The steady-state concentration of triplet WR 7930 molecules and of hydrogen atoms is reduced 2 to 3 times when mercaptoethylamine (MEA) is also present in the UV-irradiated glass. Organosulfur radicals form on MEA while hydrogen atoms and triplet-state molecules are reduced in number. Hydrogen atoms and triplet WR 7930 molecules are considered as mediators of the phototoxicity of the antimalarial drug. Thus, hydrogen atom scavanging and chemical quenching of the triplet state are possible mechanisms by which protection against phototoxic effects could be gained. Protection is demonstrated in mice receiving 20 mg per kg WR 7930 intraperitoneally and exposed to long-wave UV for 20 hr when the radioprotective aminothiol-forming compound, 2-(3-aminopropylamino) ethyl dihydrogen phosphorothioate (WR 2721), is administered at 400 mg per kg immediately before irradiation. When no protective drug is administered concurrently, WR 7930 administration results in intense erythema, edema, and eventual necrosis of ear tissues.

Molecular structures of two human DNA topoisomerase I retrosequences.

We have isolated recombinant lambda-phage clones that contain sequences complementary to the 3' half of the cDNA encoding human topoisomerase I (hTOP1). These lambda clones belong to three distinct classes: class-I clones contain sequences from the active gene located on human chromosome 20. Class-II and class-III clones contain sequences corresponding to the cDNA encoding hTOP1 from nucleotide (nt) 2208 to 3434 and from nt 1639 to 3434, respectively. These sequences exhibit the characteristic features of retroposons or retrosequences. They are most likely derived from truncated mRNA transcripts of the active gene. We propose to designate the truncated hTOP1 sequence located on chromosome 1 as the pseudogene 1 (psi 1-hTOP1) and the sequence on chromosome 22 as the pseudogene 2 (psi 2-hTOP1). Pseudogene psi 1-hTOP1 has two unique properties: it is flanked by upstream sequences which display promoter activity in transient expression assays, and it contains an open reading frame which could code for the 211 C-terminal amino acids of hTOP1. Pseudogene psi 2-hTOP1 is located within an AluI repetitive element and is flanked on one side by a (CA)21 stretch.

A new approach for EPR detection of hydroxyl radicals by reaction with sterically hindered cyclic amines and oxygen.

Sterically hindered cyclic amines react with hydroxyl radicals in the presence of oxygen to yield stable nitroxide radicals which can be detected by EPR. This reaction provides a nonconventional spin-trapping tool for detection of hydroxyl radicals.

A wide field electron microscopic analysis of the fiber constituents of the major splanchnic nerve in cat.

The fiber composition of the left major splanchnic nerve was studied in cats by electron microscopy. Comparisons were made between normal and partially degenerated nerve specimens following ventral rhizotomy (T3-L1), or spinal nerve division (T3-L1). Normal, major splanchnic nerves contained 2,500-4,000 myelinated and 10,000-15,000 unmyelinated fibers. Preganglionic fibers included approximately 90% of the finely myelinated (1-7 micrometers) and over 50% of the unmyelinated fibers. Removal of the sensory and preganglionic components by spinal nerve division revealed a third postganglionic fiber category. This included 13-38 small myelinated (1-5 micrometers) and 1,645-7,619 unmyelinated fibers. Finally, a comparison of normal and partially degenerated nerve specimens of both groups (ventral rhizotomy and spinal nerve cut) indicated that splanchnic afferents are made up of virtually all of the 120-350 large myelinated (8-14 micrometers) and 10% of the small myelinated (1-7 micrometers) fibers. A preliminary estimate indicated that about 10-20% of the unmyelinated fibers were sensory. The implications of these findings are discussed.

Mixed (composite) glandular-endocrine cell carcinoma of the stomach. Report of a case and review of literature.

A case of mixed (composite) glandular-endocrine cell carcinoma of the stomach is presented. Whereas the admixture of rare endocrine cells in ordinary adenocarcinoma of the stomach is a rather frequent occurrence, gastric tumors with an approximately equal proportion of glandular and endocrine cells are rare, and only 20 well-documented cases have been reported. Our case is unique in its range of histopathologic patterns, including well-differentiated and poorly differentiated adenoendocrine carcinoma as well as amphicrine differentiation. Immunohistochemical and electron microscopic findings are documented and the clinical characteristics of all reported cases tabulated. From the limited experience of these 21 cases, glandular-endocrine carcinoma of the stomach is found to have the following clinicopathologic features: It affects adults aged 32 to 74 years, (mean, 52.5 years) and has a male:female ratio of 1.3:1. It is located with almost equal frequency in the gastric body and antrum and has a poor prognosis, similar to that of advanced ordinary gastric carcinoma.

Aflatoxin and Reye's syndrome: a case control study.

Aflatoxin levels were determined in serum and urine of 17 patients with Reye's syndrome and in control subjects. No significant difference in aflatoxin levels was found for the two groups. However, 23% of all persons studied had levels of aflatoxin indicative of recent exposure. Aflatoxin levels were associated with ingestion of cornmeal and corn bread but not peanut-containing products. This prevalence of aflatoxin may be of public health importance.

Studies on the action of nystatin on cultured rat myocardial cells and cell membranes, isolated rat hearts, and intact rats.

The action of nystatin, a polyene antibiotic, was studied in rat myocardial cells, isolated rat hearts, and intact rats. Myocardial cells responded to 10 and 25 micrograms nystatin/ml with arrhythmias that could be minimized by elevated concentrations of K+ and Mg2+ or reversed by washing the cells. Similarly, the isolated heart responded to 100 micrograms nystatin/ml with arrhythmias that could be tempered by addition of elevated concentrations of K+ and Mg2+. The i.v. injection of the drug caused heart failure in intact animals at the 4-mg/kg dose level. At the subcellular level, nystatin made the myocardial cell membranes more rigid, as measured by electron spin resonance spectrometry. These findings indicate a parallel between physiocochemical changes caused by nystatin in the myocardial cell membrane and the biological changes caused by this drug in myocardial cells, isolated heart, and heart of the intact animal.

Dose dependency of aflatoxin B1 binding on human high molecular weight DNA in the activation of proto-oncogene.

The binding of aflatoxin B1, AFB1, a potent hepatocarcinogen, to various high molecular weight (HMW) DNAs from human normal liver and two liver cancer cell lines, Alexander primary liver carcinoma (PLC) and Mahlavu hepatocellular carcinoma (hHC) and from NIH/3T3 cell have been investigated. The kinetics of AFB1 binding to these DNAs showed similar initial rates but the extents of binding to the PLC and hHC DNAs seemed to be slightly higher. Preferential AFB1 bindings were identified in both PLC and hHC DNAs compared to normal liver DNA when analyzed by restriction endonuclease digestions and agarose gel electrophoresis. A critical AFB1 binding dosage, ranging 100 to 460 fmole/microgram DNA, was found to activate the carcinogenic effect of the Mahlavu hHC HMW DNA, but not normal liver HMW DNA, rendering it capable of inducing focal transformation in NIH/3T3 cell. Excessive AFB1 binding on the hHC and PLC HMW DNAs resulted in an "over-kill" of both cell transformation capability and templating activity of the DNA.

Mucinous adenocarcinoma of the endometrium with intestinal differentiation: a case report.

Mucinous differentiation of endocervical type has been well documented in endometrial carcinoma. However, we describe an unusual case of adenocarcinoma of the endometrium showing diffuse histological, immunohistochemical, and ultrastructural evidence of intestinal differentiation. Although intestinal differentiation has been described in mesodermally derived tissues including endocervix, ovary, and urinary tract, it has not been reported in normal endometrium. One previous case has been reported showing this pattern in endometrial carcinoma. Possible histogenetic mechanisms of this pattern are discussed.

Wide-field electron microscopy. A rapid method for the study of histologic material that provides a bridge between light and electron microscopy.

Wide fields of tissue can be rapidly examined by electron microscopy by use of Formvar films for the support of ultrathin sections on slot grids. The intervention of the grid bars of conventional mesh grids is avoided, and a continuous micrograph of the specimen at scanning magnifications can be obtained. Enough material is sublimed from the section and the supporting film by deliberate exposure to the electron beam to permit one to obtain an image with good contrast. This method of examination, which takes in all about two hours, permits examination of an extensive area of tissue in relation both to its topography at low magnifications and to its ultrastructural detail, and accordingly adds to electron microscopy a dimension characteristic of the lower powers of the light microscope. It offers the histopathologist the option of using micrographs taken during the scanning survey of a tissue to detect regions that can be readily re-examined at high magnification in the same ultrathin section.