Normal insulin-dependent activation of Akt/protein kinase B, with diminished activation of phosphoinositide 3-kinase, in muscle in type 2 diabetes

To determine whether the serine/threonine kinase Akt (also known as protein kinase B) is activated in vivo by insulin administration in humans, and whether impaired activation of Akt could play a role in insulin resistance, we measured the activity and phosphorylation of Akt isoforms in skeletal muscle from 3 groups of subjects: lean, obese nondiabetic, and obese type 2 diabetic. Vastus lateralis biopsies were taken in the basal (overnight fast) and insulin-stimulated (euglycemic clamp) states. Insulin-stimulated glucose disposal was reduced 31% in obese subjects and 63% in diabetic subjects, compared with lean subjects. Glycogen synthase (GS) activity in the basal state was reduced 28% in obese subjects and 49% in diabetic subjects, compared with lean subjects. Insulin-stimulated GS activity was reduced 30% in diabetic subjects. Insulin treatment activated the insulin receptor substrate-1-associated (IRS-1-associated) phosphoinositide 3-kinase (PI 3-kinase) 6.1-fold in lean, 3.7-fold in obese, and 2.4-fold in diabetic subjects. Insulin also stimulated IRS-2-associated PI 3-kinase activity 2.2-fold in lean subjects, but only 1.4-fold in diabetic subjects. Basal activity of Akt1/Akt2 (Akt1/2) and Akt3 was similar in all groups. Insulin increased Akt1/2 activity 1.7- to 2. 0-fold, and tended to activate Akt3, in all groups. Insulin-stimulated phosphorylation of Akt1/2 was normal in obese and diabetic subjects. In lean subjects only, insulin-stimulated Akt1/2 activity correlated with glucose disposal rate. Thus, insulin activation of Akt isoforms is normal in muscle of obese nondiabetic and obese diabetic subjects, despite decreases of approximately 50% and 39% in IRS-1- and IRS-2-associated PI 3-kinase activity, respectively, in obese diabetic subjects. It is therefore unlikely that Akt plays a major role in the resistance to insulin action on glucose disposal or GS activation that is observed in muscle of obese type 2 diabetic subjects.

P-selectin and ICAM-1 mediate endotoxin-induced neutrophil recruitment and injury to the lung and liver

The role of leukocyte adhesion molecules in endotoxin-induced organ injury was evaluated by administering intraperitoneal Salmonella enteritidis lipopolysaccharide (LPS) to wild-type (WT) mice, P-selectin-deficient mice, intercellular adhesion molecule (ICAM)-1-deficient mice, and P-selectin-ICAM-1 double-mutant mice. In WT mice, there was a sevenfold increase in the number of neutrophils present in the pulmonary vascular lavage fluid, and there were sevenfold more intracapillary neutrophils by electron-microscopic (EM) morphometry at 4 h after intraperitoneal LPS compared with that in control mice. Extravascular albumin accumulation increased approximately twofold in the lungs and liver of WT mice treated with LPS. In the double-mutant mice, although overall mortality after intraperitoneal LPS was not attenuated, there was a significant delay in mortality in the P-selectin-ICAM-1-deficient mutants compared with that in WT mice after intraperitoneal LPS (P < 0.01). Moreover, compared with LPS-treated WT mice, lung and liver extravascular albumin accumulation was significantly lower in LPS-treated P-selectin-ICAM-1 double-mutant mice. Lung myeloperoxidase activity, normalized per 1,000 circulating neutrophils, increased after endotoxin in WT and P-selectin-deficient mice but not in P-selectin-ICAM-1 double-mutant mice. In addition, lung and liver myeloperoxidase activity per 1,000 circulating neutrophils in endotoxin-treated ICAM-1-deficient mice and P-selectin-ICAM-1 double mutants was significantly lower compared with that in endotoxin-treated WT mice. These data suggest that P-selectin and ICAM-1 significantly contribute to lung and liver injury after systemic endotoxemia.

Correlation between expression of matrix metalloproteinase-2 (MMP-2), and matrix metalloproteinase-9 (MMP-9) and angiogenesis in colorectal adenocarcinoma

Matrix metalloproteinases-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), which degrade extracellular matrix, are believed to play a crucial role in tumor invasion and metastasis. Angiogenesis is also perceived as an important step in tumor growth and metastasis. To investigate the expression of MMPs and the correlation between the expression of MMPs and angiogenesis in colorectal adenocarcinoma, we studied 72 cases of colorectal adenocarcinoma in Inha University Hospital from 1996 to 1997. We evaluated the expression of MMPs by immunohistochemistry and angiogenesis by counting the microvessels. The expression of MMP-2 was increased according to the Astler-Coller stage (p< 0.05). Angiogenesis in the metastatic group was higher than that of the localized one (p<0.05). The expression of MMP-2 positively correlated with angiogenesis (p<0.05), and marked expression of MMP-9 positively correlated with angiogenesis (p<0.05). The present results suggest that the expression of MMP-2 provides clues for tumor progression and angiogenesis provides significant information to predict whether metastasis is present in colorectal adenocarcinoma.

Biliary lymphoepithelioma-like carcinoma not associated with Epstein-Barr virus

We report the case of a 64-year-old man who presented with a hepatic mass and macronodular cirrhosis. The pathologic findings revealed a lymphoepithelioma-like carcinoma arising in the hepatobiliary tract that was morphologically identical to nasopharyngeal undifferentiated carcinoma. However, this tumor was not associated with Epstein-Barr virus infection in molecular studies. Macronodular cirrhosis associated with hepatitis C virus was present in the background liver.

Effects of 2-bromopropane on spermatogenesis in the Sprague-Dawley rat

In 1995, 2-bromopropane (2-BP) was associated with occupational reproductive and hematopoietic toxicity in Korea. The effect of 2-BP on spermatogenesis, or Leydig cells, has not been determined in adult rats. In the present study, 40 ten-week-old Sprague-Dawley (SD) rats were treated orally with 3.5 g/kg/d of 2-BP for 3 consecutive days. At 1, 3, 5, 7, 14, 28, 42, and 70 d after treatment, testes were perfused with Karnovsky's solution or immersed in Bouin's solution, embedded in plastic or Epon and evaluated with light and electron microscopy. DNA ploidy distributions of testicular suspensions were determined by flow cytometry, which allowed comparison of quantitative spermatogenesis with histopathologic observations. Degeneration of spermatogonia was observed during Stages I-IV in seminiferous tubules on Day 1 after treatment. Spermatocytes, spermatids, Sertoli cells, and Leydig cells appeared normal in the early stage of the study. Whereas spermatid retention in Stages IX-XI was observed on Day 7 after treatment, depletion of spermatocytes and spermatids continued over time, followed by a marked increase of germ cells on Day 42 after treatment. However, the seminiferous tubules did not completely recover by study termination. Leydig cell cellularity increased mildly without any significant morphologic modification at the end of the study. Immunohistochemistry using an antibody against proliferating cell nuclear antigen (PCNA), showed an increased number of immunoreactive Leydig cells in the interstitium. In the flow cytometry analysis, proportions of diploid and tetraploid cells gradually decreased time-dependently until Day 28 after treatment, but showed an increase on Day 42, followed by a decrease on Day 70 after treatment. These data are strengthened by qualitative descriptions of lesions observed by histopathology. These results suggest that a high dose of 2-BP can decrease spermatogenesis by adversely affecting spermatogonia followed by depletion of spermatocytes, spermatids, and spermatozoa, with subsequent testicular atrophy. The atrophied testes may not regenerate completely. The number of Leydig cells may increase mildly with 10 weeks of recovery.

Oxamflatin is a novel antitumor compound that inhibits mammalian histone deacetylase

Oxamflatin [(2E)-5-[3-[(phenylsufonyl) aminol phenyl]-pent-2-en-4-ynohydroxamic acid] induces transcriptional activation of junD and morphological reversion in various NIH3T3-derived transformed cell lines. We found that oxamflatin showed in vitro antiproliferative activity against various mouse and human tumor cell lines with drastic changes in the cell morphology and in vivo antitumor activity against B16 melanoma. Oxamflatin caused an elongated cell shape with filamentous protrusions as well as arrest of the cell cycle at the G1 phase in HeLa cells. These phenotypic changes of HeLa cells were apparently similar to those by trichostatin A (TSA), a specific inhibitor of histone deacetylase (HDAC). The effect of oxamflatin on the transcriptional activity of the cytomegalovirus (CMV) promoter was examined and compared with known HDAC inhibitors, TSA, sodium n-butyrate, and FR901228. Oxamflatin as well as all these inhibitors greatly enhanced the transcriptional activity of the CMV promoter in a dose-dependent manner. Oxamflatin, like TSA, inhibited intracellular HDAC activity, as a result of which marked amounts of acetylated histone species accumulated. Finally, effects on expression of several endogenous genes involved in cell morphology and cell cycle control in HeLa cells were analysed. Expression of gelsolin, cyclin E and Cdk inhibitors including p21WAF1/Cip1 was highly augmented, while that of cyclin A and cyclin D1 was decreased by oxamflatin. These results suggest that changes in the expression pattern of the genes regulating cell morphology and the cell cycle due to histone hyperacetylation are responsible for the antitumor activity, the morphological change and the cell cycle arrest induced by oxamflatin.

Sex differences in dizocilpine (MK-801) neurotoxicity in rats

The sex differences in the clinical signs and the distribution of astrocytic glial fibrillary acidic protein (GFAP) induced by an N-methyl-d-aspartate antagonist, dizocilpine (MK-801), were examined. A single intraperitoneal injection of MK-801 (5 mg/kg body weight) caused a prolonged recumbency (35-40 h), leading to a severe loss of body weight in female rats, in contrast to a light effect in males, independent of age. Early salivation or lacrimation was also severe in females and delayed bloody lacrimation was observed in females only. The pretreatment with 17β-estradiol (0.1 or 1.0 mg/kg body weight) made early signs worse in both sexes, but a remarkable mortality (20-40%) was observed in females only. The treatment with MK-801 greatly enhanced GFAP expression in retrospenial cortex of both sexes with a higher enhancement in females. The MK-801-induced expression of GFAP was further increased by the pretreatment with 17β-estradiol (1 mg/kg body weight) in females. Overall, the expression of GFAP in the retrospenial cortex of rats treated with MK-801 appeared to be higher in females than males, somewhat in parallel with more severe clinical signs in females. The results indicate the higher sensitivity of female rats to MK-801 neurotixicity, and the possible involvement of 17β-estradiol in the sex differences of the sensitivity.

Identification of Vibrio parahaemolyticus strains at the species level by PCR targeted to the toxR gene

The DNA colony hybridization test with the polynucleotide probe for Vibrio parahaemolyticus toxR gene was performed. All 373 strains of V. parahaemolyticus gave positive results, and the strains belonging to four other Vibrio species including Vibrio alginolyticus gave weakly positive results, suggesting that toxR sequence variation may reflect the phylogenetic relationships of Vibrio species. We then established a toxR-targeted PCR protocol for the specific detection of V. parahaemolyticus.

Organophosphate-induced brain injuries: delayed apoptosis mediated by nitric oxide

The features of organophosphate-induced brain injuries were investigated. Rats were poisoned intraperitoneally with 9 mg/kg (1.8 LD(50)) of diisopropylfluorophosphate. Pyridostigmine bromide (0.1 mg/kg) and atropine methylnitrate (20 mg/kg), which are centrally inactive, were pre-treated intramuscularly to reduce the mortality and eliminate peripheral signs. Diisopropylfluorophosphate induced severe limbic seizures, and early necrotic and delayed apoptotic brain injuries. The necrotic brain injury was observed to be maximal as early as 1 h after diisopropylfluorophosphate treatment predominently in hippocampus and piriform/entorhinal cortices, showing a spongiform change (malacia) of neuropils in severe cases. In contrast, typical apoptotic (TUNEL-positive) cells started to appear at 12 h in thalamus, and a mixed type in amygdala. Separately, nitrite/nitrate content in cerebrospinal fluid was found to significantly increase after 2 h, reaching a maximal level at 6 h. Pre-treatment with l-N(G)-nitroarginine, an inhibitor of nitric oxide synthase, reduced nitrite/nitrate content and, noteworthy, attenuated only apoptotic brain injury in all four brain regions without affecting seizure intensity and necrotic injury. Taken together, the delayed apoptotic injury of brain induced by diisopropylfluorophosphate poisoning in rats might be mediated in part through nitric oxide production.

Neuronal differentiation of neuro 2a cells by inhibitors of cell cycle progression, trichostatin A and butyrolactone I

Trichostatin A (TSA, 17 nM), a specific and reversible inhibitor of histone deacetylase induced neurite network formation at and after 4 days. The networks were preserved for at least 3 weeks in the presence of TSA. Butyrolactone I (BLI, 23.6 microM), an inhibitor of cdc2 and cdk2 kinases, also induced neurite extension. Both compounds enhanced the acetylcholinesterase activity of the cells. Cell cycle progression of the cells was blocked by TSA (17 nM) at G1 phase alone. Furthermore, the level of histone hyperacetylation and p21(WAF1) expression in TSA-treated cells increased transiently. These findings suggest that the induction of the neuronal differentiation in Neuro 2a cells by these agents requires the cell cycle arrest at G1 phase, which is caused by inhibition of cycline dependent kinase, a target molecule of BLI and p21(WAF1).

Screening and selection of acid and bile resistant bifidobacteria

Human fecal samples were used as a source of Bifidobacterium strains which are resistant to both acid and bile. The procedure used for screening was as follows: enrichment of Bifidobacterium strains with Bifidobacterium-selective transgalacto-oligosaccharide-propionate (TP) medium followed by acid (pH 2.0) and bile salt stressing (1.5% bile salt (w/v)). Two selected Bifidobacterium strains, designated HJ 30 and SI 31, showed considerably higher rates of survival when incubated in 50 mM phosphate buffer solution adjusted to pH 2.0 or 3.0 or in 50 mM phosphate buffer (pH 7.0) containing 0.5 or 1.0% (w/v) bile salt. HJ 30 and SI 31 were the only strains to have significant growth in Man Rogosa Sharpe (MRS) medium at 0.15% bile salt. All strains tested had similar growth rates in the absence of bile or at an initial pH value of 5.0 or 7.0 as determined by optical density measurements. For SI 31 the number of viable cell counts remained high (6 x 10(7) cfu/ml) for up to 72 h when grown in the skim milk medium, whereas all other strains examined declined to below 10(5) cfu/ml. These results demonstrate that the screening procedures developed in this study are effective for the selection of acid and bile resistant Bifidobacterium strains.

Involvement of phospholipase A2 activation in anthrax lethal toxin-induced cytotoxicity

The molecular mechanism of cytotoxic effect exerted by the lethal toxin (LeTx) of Bacillus anthracis is not well understood. In the present study, using primary culture of mouse peritoneal macrophages, we have investigated possible cytotoxic mechanisms. LeTx was not found to induce high levels of nitric oxide (NO) production for NO-mediated toxicity. Fragmentation of DNA, a biochemical marker of apoptosis, was not observed in LeTx-treated cells. Pretreatment of cells with antioxidants such as melatonin and dehydroepiandrosterone (DHEA) did not protect the LeTx-induced cytotoxicity. However, addition of phospholipase A2 (PLA2) inhibitors (quinacrine, p-bromophenacyl bromide, manoalide, butacaine) to the culture medium resulted in the inhibition of cytotoxicity of LeTx in a dose-dependent manner. LeTx-induced cytotoxicity was also inhibited by the tyrosine-specific protein kinase inhibitor genistein, but not by the protein kinase C inhibitors staurosporine or H-7. The results of these studies indicate a role for PLA2 and protein kinase in the cytotoxic mechanism of macrophages by anthrax lethal toxin.

Glucosamine infusion in rats rapidly impairs insulin stimulation of phosphoinositide 3-kinase but does not alter activation of Akt/protein kinase B in skeletal muscle

Glucosamine, a metabolite of glucose via the hexosamine biosynthetic pathway, potently induces insulin resistance in skeletal muscle by impairing insulin-induced GLUT4 translocation to the plasma membrane. Activation of phosphoinositide (PI) 3-kinase is necessary for insulin-stimulated GLUT4 translocation, and the serine/threonine kinase Akt/protein kinase B (PKB) is a downstream mediator of some actions of PI 3-kinase. To determine whether glucosamine-induced insulin resistance could be due to impaired signaling, we measured insulin receptor substrate (IRS)-1 and insulin receptor tyrosine phosphorylation; PI 3-kinase activity associated with IRS-1, IRS-2, and phosphotyrosine; and Akt activity and phosphorylation in skeletal muscle of rats infused for 2 h with glucosamine (6.0 mg x kg(-1) x min(-1)) or saline. Euglycemic-hyperinsulinemic clamp studies (12 mU x kg(-1) x min(-1) insulin) in awake rats showed that glucosamine infusion resulted in rapid induction of insulin resistance, with a 33% decrease in glucose infusion rate (P < 0.01). Tissues were harvested after saline alone (basal), 1 min after an insulin bolus (10 U/kg), or after 2 h of insulin clamp in saline- and glucosamine-infused rats. After 1 min of insulin stimulation, phosphorylation of IRS-1 and insulin receptor increased 6- to 8-fold in saline-infused rats and 7- to 10-fold in glucosamine-infused rats. In saline-infused rats, 1 min of insulin stimulation increased PI 3-kinase activity associated with IRS-1, IRS-2, or phosphotyrosine 7.6-, 6.4-, and 10-fold, respectively. In glucosamine-infused rats treated for 1 min with insulin, PI 3-kinase activity associated with IRS-1 was reduced 28% (P < 0.01) and that associated with phosphotyrosine was reduced 43% (P < 0.01). Insulin for 1 min stimulated Akt/PKB activity approximately 5-fold in both saline- and glucosamine-infused rats; insulin-induced hyperphosphorylation of Akt/PKB was not different between groups. Glucosamine infusion alone had no effect on tyrosine phosphorylation of the insulin receptor or IRS-1 or on stimulation of PI 3-kinase or Akt/PKB activity. However, 2 h of insulin clamp reduced PI 3-kinase activity associated with IRS-1, IRS-2, or phosphotyrosine to <30% of that seen with 1 min of insulin. No effect of glucosamine was seen on these signaling events when compared with 2 h of insulin clamp without glucosamine. Our data show that 1) glucosamine infusion in rats is associated with an impairment in the early activation of PI 3-kinase by insulin in skeletal muscle, 2) this insulin-resistant state does not involve alterations in the activation of Akt/PKB, and 3) prolonged insulin infusion under clamp conditions results in a blunting of the PI 3-kinase response to insulin.

Effect of long-term exercise on gene expression of insulin signaling pathway intermediates in skeletal muscle

To elucidate the molecular mechanism underlying insulin sensitivity, we have thought to investigate gene expression of insulin signaling pathway intermediates in skeletal muscle from sedentary and endurance-trained rats. Adult male Sprague-Dawley rats were trained for 9 weeks on a treadmill; 30 m/min at a 6 degrees incline, 90 min/day, 5 days/week. The levels of PI 3-kinase, GLUT4, p70 S6 kinase and Ras mRNA were significantly increased by 89, 40, 38, and 47%, respectively, with running training; however, the Nck mRNA level was decreased by 24%. mRNA levels of SHP-2, Grb2, Sos, Shc, GAP, p62 and p90 S6 kinase were unaltered by running training. We have previously reported that endurance training increases mRNA levels of insulin receptor, IRS-1 and ERK1 in skeletal muscle of rats. Taken together, our data suggest that gene expression of the insulin signal pathway intermediates is modulated by endurance training that may be associated with alteration of insulin sensitivity.

A new treatment for syringoma. Combination of carbon dioxide laser and trichloroacetic acid

BACKGROUND

Although syringoma represents a benign tumor of skin appendage, multiple and diffuse facial lesions can cause cosmetic problems for the affected individuals. Scarring, recurrence and postinflammatory hyperpigmentation can be serious troubles, especially for oriental people receiving various therapeutic modalities.

OBJECTIVE

The purpose of this study was to evaluate the histopathologic and clinical efficacy of a new therapeutic approach for syringoma, consisting of combination of carbon dioxide (CO2) laser and 50% trichloroacetic acid (TCA).

METHODS

Eighty skin biopsy specimens (45 patients) were evaluated to determine the depth of syringoma lesion. Among these, 28 specimens were obtained after a single test-pulse of CO2 laser (focused, superpulsed mode, power setting of 0.7-2 watts, beam diameter of 0.1 mm, pulse duration of 0.1 seconds), and 3 specimens after one pass of CO2 laser and 50% TCA. The depths of laser-induced vaporization and TCA-induced tissue necrosis were measured. Twenty patients were treated with the combination therapy of CO2 laser (two passes of laser) and 50% TCA. Clinical effectiveness and complications of combination therapy were evaluated by direct observation and photographs.

RESULTS

Tumor depth: Analysis of eight specimens revealed tumor depth of 0.70 +/- 0.20 mm (mean +/- SD), ranging from 0.4-1.2 mm. There were no correlations between tumor depth and age of onset or duration of the tumor. Laser penetration depth: CO2 laser irradiation, 0.7-2 watts, induced vaporization of 0.29 +/- 0.12 mm in depth with carbonized rim of 0.1 +/- 0.03 mm width (n = 28 from 15 patients). With laser power of 1 watt, vaporization ranged from 0.17-0.45 mm in depth. Laser and TCA induced necrosis: TCA application resulted in extra tissue necrosis of 0.22-0.25 mm in depth beyond the level achieved by laser vaporization.

CLINICAL FINDINGS

Among the 20 patients treated with the combination therapy, therapeutic effect for 11 patients was excellent, 6 patients showed good clinical response, and 3 patients were fair. There were no serious complications resulting from this procedure such as infection, scarring or textural change.

CONCLUSION

The application of 50% TCA after CO2 laser irradiation was effective for removing deep-seated syringoma cells and for reducing the side effects, especially scarring. To the best of our knowledge, this is the first study introducing the combination of CO2 laser and TCA for removal of syringoma.

phd1+, a histone deacetylase gene of Schizosaccharomyces pombe, is required for the meiotic cell cycle and resistance to trichostatin A

A gene named phd1+ encoding a protein highly homologous to the yeast and human histone deacetylases, such as Saccharomyces cerevisiae Rpd3p and human HDAC1, was cloned from Schizosaccharomyces pombe. The immune complex isolated from S. pombe cells expressing Phd1 fused to the FLAG epitope showed histone deacetylase activity, which was inhibited by trichostatin A (TSA), a specific inhibitor of histone deacetylase. The null mutation of phd1+ resulted in a marked decrease in the total cellular histone deacetylase activity and an increase in the sensitivity to TSA. Although the phd1 disruptant showed no obvious defect in the mitotic cell cycle or mating, both homothallic haploid and heterothallic diploid cells failed to form spores in the absence of phd1+. These results indicate that phd1+ encodes a histone deacetylase, which is involved in the meiotic cell cycle in S. pombe.

Incidence and predictors of cervical dysplasia in patients with minimally abnormal Papanicolaou smears

OBJECTIVE

To estimate the incidence of dysplasia in patients with Papanicolaou smears showing atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesions (SIL) and to identify clinical predictors of dysplasia in these patients.

METHODS

Patients referred for ASCUS and low-grade SIL were reviewed retrospectively. All patients were evaluated with immediate colposcopy. A multivariate logistic regression analysis was performed to identify clinical predictors of histologic SIL and histologic high-grade SIL.

RESULTS

One hundred thirty-seven (34%) of 406 consecutive patients had histologic SIL. Regression analysis identified age (under 35 versus 35 years or above) and initial smear (low-grade SIL versus ASCUS) as statistically significant predictors of histologic SIL and high-grade SIL (P < .001). When patient outcomes were analyzed by age and initial Papanicolaou smear results, the subgroup of patients 35 years or older with ASCUS had low incidences of histologic SIL (14%) and high-grade SIL (1%). The other subgroups (under 35 years with ASCUS, under 35 years with low-grade SIL, and 35 years or older with low-grade SIL) had incidences of histologic SIL and histologic high-grade SIL of at least 28% and 14%, respectively.

CONCLUSION

The high incidence of dysplasia in patients with minimally abnormal Papanicolaou smears suggests that immediate colposcopy might be appropriate for many of these patients. Age and initial Papanicolaou smear are predictive of dysplasia and might be used to select patients who have low incidence of dysplasia and might not require immediate colposcopy.

Isolation of an Escherichia coli O157:H7 strain producing Shiga toxin 1 but not Shiga toxin 2 from a patient with hemolytic uremic syndrome in Korea

Escherichia coli strains isolated from patients with diarrhea or hemolytic uremic syndrome (HUS) at Pusan University Hospital, South Korea, between 1990 and 1996 were examined for traits of the O157:H7 serogroup. One strain isolated from a patient with HUS belonged to the O157:H7 serotype, possessed a 60-MDa plasmid, the eae gene, and ability to produce Shiga toxin 1 but not Shiga toxin 2. Arbitrarily primed PCR analysis suggested that this strain is genetically very close to a O157:H7 strain isolated in Japan.

Attenuated phase-shifting masks of chromium aluminum oxide

Chromium aluminum oxide was chosen as a new candidate for use as an attenuated phase-shifting mask (Att-PSM) material. The compositions of films were correlated with optical properties. With the measured and the fitted data, we simulated the transmittance and the phase shift using the matrix method. Consequently, we acquired optimum parameters for Att-PSM's, such as Al/Cr = 1.9-2.5 and d = 120 nm at a 193-nm wavelength, Al/Cr = 1.0-1.7 and d = 128 nm at a 248-nm wavelength, and Al/Cr = 0-0.1 and d = 170 nm at a 365-nm wavelength. This simulation was verified by transmittance measurement.

Diagnostic and therapeutic advances in gynecologic oncology: screening for gynecologic cancer

Endometrial carcinoma is associated with a good prognosis because patients tend to present with early disease. Mass screening is therefore unlikely to be of benefit. High-risk populations may benefit from screening, but no prospective studies have demonstrated a benefit in any population. The most promising modality for screening appears to be TVS, and a normal TVS may also preclude the need for further evaluation of symptomatic patients. The appropriate use of TVS in patients on tamoxifen is currently unknown. Hysteroscopy and endometrial biopsy may have a role in the evaluation of symptomatic patients but do not appear promising as screening modalities.

FR901228, a potent antitumor antibiotic, is a novel histone deacetylase inhibitor

Screening for microbial metabolites that induce transcriptional activation of the SV40 promoter resulted in the identification of two known compounds, FR901228 and trichostatin A (TSA). FR901228 is a potent antitumor drug that is currently under clinical investigation. TSA is a specific inhibitor of histone deacetylase. Despite structural unrelatedness, both FR901228 and TSA greatly enhanced the transcriptional activity of the SV40 promoter in an enhancer-dependent manner. The effects of FR901228 on the cell cycle, chromatin structure, and histone acetylation were examined and compared with those of TSA. Both compounds caused arrest of the cell cycle at both G1 and G2/M phases and induction of internucleosomal breakdown of chromatin. FR901228, like TSA, inhibited intracellular histone deacetylase activity, as a result of which marked amounts of acetylated histone species accumulated. FR901228 is therefore a new type of histone deacetylase inhibitor, whose chemical structure is unrelated to known inhibitors such as trichostatins and trapoxins.

Characterization of the leupeptin-inactivating enzyme from Streptomyces exfoliatus SMF13 which produces leupeptin

Leupeptin-inactivating enzyme (LIE) was purified from Streptomyces exfoliatus SMF13 by ammonium sulphate fractionation of cell-free culture broth, ultrafiltration, anion-exchange chromatography on DEAE-Sephadex A-50 and gel filtration chromatography on Sephadex G-75. The molecular mass of the purified enzyme was measured as 34700 Da and the N-terminal amino acid sequence was APTPPDIPLANVPA. Acetyl-leucine, leucine and argininal were identified as the products of leupeptin inactivated by the LIE, indicating that leupeptin is inactivated by hydrolysis of peptide bond between leucine and leucine and between leucine and argininal of leupeptin (acetyl-leucine-leucine-argininal). Synthetic-peptide substrates specificity of LIE showed that LIE has absolute specificity for peptide bonds with leucine in the P1 position, suggesting that LIE is a leucine-specific protease. The optimum pH and temperature were pH 9.0 and 45 degrees C, respectively. LIE activity was inhibited by metalloprotease inhibitors such as EDTA, EGTA, o-phenanthroline and bestatin, but activated by Mg2+ and Ca2+, suggesting that the enzyme is a metalloprotease. Aerial-mycelium growth and aerial spore formation of S. exfoliatus SMF13 were inhibited by the addition of bestatin, an inhibitor of LIE. The inhibition of morphological differentiation was due to the inhibition of trypsin-like protease (TLP) activity, which is essential for aerial-mycelium formation and is inhibited specifically by remaining leupeptin that was not inactivated. These results show that LIEs play a role in controlling the amount of leupeptin during colony development. Therefore, it is suggested that the physiological function of LIE is to inactivate leupeptin when or where TLP activity is required for aerial-mycelium formation.

The protective effects of lactoferrin feeding against endotoxin lethal shock in germfree piglets

The unique germfree, colostrum-deprived, immunologically "virgin" piglet model was used to evaluate the ability of lactoferrin (LF) to protect against lethal shock induced by intravenously administered endotoxin. Piglets were fed LF or bovine serum albumin (BSA) prior to challenge with intravenous Escherichia coli lipopolysaccharide (LPS), and temperature, clinical symptoms, and mortality were tracked for 48 h following LPS administration. Prefeeding with LF resulted in a significant decrease in piglet mortality compared to feeding with BSA (16.7 versus 73.7% mortality, P < 0.001). Protection against the LPS challenge by LF was also correlated with both resistance to induction of hypothermia by endotoxin and an overall increase in wellness, as quantified by a toxicity score developed for these studies. In vitro studies using a flow cytometric assay system demonstrated that LPS binding to porcine monocytes was inhibited by LF in a dose-dependent fashion, suggesting that the mechanism of LF action in vivo may be inhibition of LPS binding to monocytes/macrophages and, in turn, prevention of induction of monocyte/macrophage-derived inflammatory-toxic cytokines.

Apoptosis as a mechanism of 2-chloroethylethyl sulfide-induced cytotoxicity

Apoptosis is a mode of active cell death. We have examined whether 2-chloroethylethyl sulfide (CEES), a sulfur vesicating agent, triggers apoptosis as a cytotoxic mechanism. Incubation of thymocytes with CEES, resulted in an induction of apoptotic features of cell death. Treatment of cells with 100 microM CEES for 5 h increased DNA fragmentation to approximately 40% of control. The fragmentation of DNA was visualized by agarose gel electrophoresis. It showed ladder pattern of DNA fragmentation, which indicates internucleosomal cleavage of DNA. Further evidence of apoptosis was observed in morphological changes of nuclei by using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method. The percentage of TUNEL positive cells was dependent upon CEES concentrations. CEES induced the classical morphological features of apoptosis in nucleus. These features were accompanied by condensation of chromatin, which arranged in sharply declined clumps and fragmentation of nucleus. To study requirement for synthesis of new protein in CEES-induced apoptosis, we studied the effect of cycloheximide for apoptotic activity. This protein synthesis inhibitor did not suppress the CEES-induced apoptotic activity. Taken together, these results suggest that CEES-induced apoptosis as a cytotoxicmechanism and this process occurs independent of synthesis of new protein.

Detection of Escherichia coli O157:H7 in the beef marketed in Malaysia

Twelve strains of Escherichia coli O157:H7 were isolated from 9 of 25 beef samples purchased from retail stores in Malaysia. These strains produced Shiga toxin 2 with or without Shiga toxin 1 and had the eae gene and a 60-MDa plasmid. The antibiograms and the profiles of the arbitrarily primed PCR of the strains were diverse, suggesting that the strains may have originated from diverse sources.

Cloning of Novel Maltooligosaccharide-Producing Amylases as Antistaling Agents for Bread

For better understanding of the antistaling effect of starch-hydrolyzing enzymes, maltose-, maltotriose-, or maltotetraose-producing enzymes were applied to bread mix and the retrogradation rate of the bread was determined using differential scanning calorimetry. A new amylase isolated from Bacillus subtilis SUH 4-2, which selectively produces maltose and maltotriose from starch solution (amylase II), and another amylase from Streptomyces albus KSM-35, mainly producing maltotetraose and maltotriose (amylase IV), were cloned, characterized, and evaluated as antistaling agents for bread. Addition of amylase II or amylase IV significantly reduced the bread staling rate during 7 days of storage (p < 0.05), and especially amylase IV was as effective as a commercial enzyme, Novamyl. Analyses of the maltooligosaccharide composition of bread suggest that maltotriose and maltotetraose produced by the enzyme reaction are responsible for retarding bread retrogradation.

Porcine myelomonocytic markers: summary of the Second International Swine CD Workshop

Forty five mAbs submitted to the Second International Swine CD workshop were analyzed by six different laboratories for their possible reactivity with porcine myelomonocytic cells using flow cytometry and immunohistochemistry. As a result of these analyses, a new swine workshop cluster, SWC9, composed of two mAbs that recognize an antigen selectively expressed on mature macrophages, was defined. In addition, several mAbs were identified, allowing the differentiation of granulocytes from monocytes/macrophages, or monocytes from macrophages. Further work is required to identify the antigen recognized by these mAbs. Nevertheless, they should already prove useful for the identification of different stages in the macrophage maturation/differentiation, and will certainly aid analyses on the complexity of the mononuclear phagocyte system in the pig. Finally, the cross-reactivity of three anti-human CD14 mAbs with porcine myelomonocytic cells was established in this workshop.

Workshop studies with monoclonal antibodies identifying a novel porcine differentiation antigen, SWC9

Two monoclonal antibodies (mAb) within cluster M4 of the myeloid section of the Second International Swine CD Workshop, C4 (No. 144) and PM18-7 (No. 192), showed reactivity with thymocytes and among cells of myelomonocytic origin with mature macrophages but not with monocytes and granulocytes. Both mAb recognize a protein showing two bands of 205 kDa and 130 kDa under both reducing and non-reducing conditions. Although epitope mapping with these mAb could not be performed, this cluster received the SWC9 designation.

Does hysteroscopy improve upon the sensitivity of dilatation and curettage in the diagnosis of endometrial hyperplasia or carcinoma?

OBJECTIVE

The objective of this study was to determine whether hysteroscopy improved upon the diagnostic sensitivity of dilatation and curettage (D+C) in the detection of endometrial hyperplasia and carcinoma.

METHODS

A retrospective chart review was conducted of all patients undergoing hysteroscopy/D+C for abnormal uterine bleeding between 1991 and 1995. Hysteroscopic impressions and D+C diagnoses were compared.

RESULTS

Three hundred seventy-three patients were included in the study. Of the 61 patients with D+C demonstrating hyperplasia, the hysteroscopic impression was hyperplasia in 32 (52%). Of the 10 patients with D+C demonstrating carcinoma, the hysteroscopic impression was hyperplasia in 8 (80%) and carcinoma in 2 (20%). Two additional cases of carcinoma were diagnosed within 6 months of hysteroscopy/D+C, and both had been missed on both hysteroscopy and D+C. Of 204 patients with a normal hysteroscopic impression, 23 (11%) had hyperplasia on D+C.

CONCLUSIONS

Hysteroscopy did not improve upon the sensitivity of D+C in the detection of endometrial hyperplasia or carcinoma.

Phylogenetic analysis of the nef gene reveals a distinctive monophyletic clade in Korean HIV-1 cases

To study the genetic variation of the HIV-1 strains prevalent in South Korea, we analyzed the nef sequences derived from 46 HIV-1-positive individuals living in various geographic regions in Korea. Phylogenetic analysis revealed four subtypes of HIV-1: A (3 patients), B (41 patients), D (1 patient), and a type that could not be clearly classified to any known subtype (1 patient). Thirty-five of the 41 Korean subtype B isolates formed a distinct monophyletic clade that is not related to any of the international sequences from the Los Alamos Database or GenBank as of June 1997. Indeed, the presence of unique conserved sequences was identified among the Korean isolates in this Korean subtype B group. The variations in the nucleotide sequences of a majority (32 of 35) subtype B samples within the Korean clade were 1.9% to 8.8%, and amino acid sequences varied from 3.9% to 15.5%. These results suggest that HIV-1 strains currently present in South Korea might have originated from a few sources or might be developing through a certain selective pressure. This is the first report on the molecular nature of the HIV-1 infection present in South Korea.

A novel Alcian yellow-toluidine blue (Leung) stain for Helicobacter species: comparison with standard stains, a cost-effectiveness analysis, and supplemental utilities

Helicobacter pylori (Hp) gastritis is a worldwide problem significantly associated with duodenal and gastric peptic ulcer disease, gastric carcinomas, and MALT-type lymphomas. A simple, rapid, reproducible, reliable, and inexpensive stain to detect the organism in gastric biopsy specimens is thus of great value. To assess the reliability and cost-effectiveness of a novel Alcian yellow-toluidine blue (Leung) stain for Hp, we stained 60 endoscopic mucosal biopsy specimens from patients with Hp gastritis and measured time to detection of organism, Hp numbers (scale, 1-5), and technical costs. We also stained serial 5-microm step sections of 17 of these cases with the Giemsa and modified Steiner (MS) methods, and similar measurements were made. Also, specimens from various normal gastrointestinal sites and metaplastic lesions, as well as four cases each of giardiasis and cryptosporidiosis, were stained with the Leung method. In the subset of 17 cases, the Leung stain enhanced detection time and compared favorably with the Giemsa method, though the MS method was somewhat superior. Hp scores were similar among all groups. Mean time to detection and Hp scores were similar in the larger (n = 60) group stained with hematoxylin and eosin and the Leung stain. Material costs and technologist's time for Giemsa stains, however, were greater than for the Leung stain, and technologist's time for MS was nearly fourfold that of the Leung stain. With the Leung method, mucus from all gastrointestinal sites and metaplastic lesions stained yellow, and this stain provided excellent contrast and morphologic definition in giardiasis and cryptosporidiosis. We suggest that the newly developed Alcian yellow-toluidine blue (Leung) histochemical stain is a good choice as the standard for routine Hp staining because it is the cheapest and easiest to prepare and because pathologists' detection with this stain compares favorably with detection times achieved with more traditional and established methods.

Effectiveness of procyclidine in combination with carbamate prophylactics against diisopropylfluorophosphate poisoning

The protective effect of cholinolytics such as procyclidine and atropine, in combination with carbamate prophylactics, against diisopropylfluorophosphate poisoning was examined in mice. Doses of carbamates were optimized, based on the maximum sign-free dose, the time course of cholinesterase inhibition and the protective potential against diisopropylfluorophosphate poisoning. Centrally-active physostigmine was more toxic than centrally-inactive pyridostigmine and the toxic signs of carbamates appeared to be closely related to the level of inhibition of brain cholinesterase activity. In combination with atropine, physostigmine was more effective than pyridostigmine in protecting mice intoxicated with diisopropylfluorophosphate. Moreover, centrally-active atropine sulfate was a more effective co-antidote to carbamates than centrally-inactive atropine methylnitrate. The most prominent protection was achieved with the combination of carbamates and procyclidine, a centrally-active cholinolytic showing anticonvulsion, which was also observed to prevent diisopropylfluorophosphate-induced convulsions (Kim et al., 1997). Taken together, it is suggested that procyclidine could be a possible substitute for atropine as an antidote to diisopropylfluorophosphate poisoning.

Co-existing gastric cancer and duodenal ulcer disease: role of Helicobacter pylori infection

BACKGROUND

The association of gastric cancer and chronic duodenal ulcer disease is considered rare. In fact duodenal ulcer disease is believed to somehow "protect" against the development of gastric cancer. Helicobacter pylori infection is an important factor in the development of gastric cancer. No detailed investigation on the prevalence of H. pylori in coexistence of gastric cancer and duodenal ulcer disease has been performed. We evaluated the frequency of H. pylori infection in the patients with co-existence of gastric cancer and duodenal ulcer disease.

MATERIALS AND METHODS

During the period March 1994 to February 1995, we collected data from 3,652 patients in whom esophagogastroduodenoscopy was done. During this period, when the cancerous or ulcerative lesions in stomach or duodenum were found, rapid urease tests were performed.

RESULTS

Six patients had concurrent gastric carcinoma and duodenal ulcer disease. Three of the cases had early gastric carcinoma; 2 had active duodenal ulcers and one had a duodenal ulcer scar; all 3 had positive rapid urease tests. The patients with early gastric cancer were younger than the individuals with advanced gastric cancer.

CONCLUSIONS

The co-existence of both diseases may be higher than reported from Western countries or from Peru which may either reflect the high prevalence of circulation of H. pylori ulcer and cancer strains in Korea and the co-infection with both types of organism in some individuals.

[Levels of thermostable direct hemolysin production by Vibrio parahaemolyticus strains carrying both tdh and trh genes]

One hundred and twenty-five strains of Vibrio parahaemolyticus carrying both the tdh and trh genes were selected from the strains isolated from the travelers with diarrhea by an hybridization test using polynucleotide probes. The levels of TDH produced by these strains and the association between the TDH levels and related characteristics in these strains were analyzed. The TDH level varied greatly from strain to strain, but none of the levels was as high as that of the typical Kanagawa phenomenon-positive strains. The strains were classified into "TDH producer" (18 strains), "Low-level TDH producer" (85 strains), and "No TDH producer" (22 strains) based on the results of a modified Elek test and the hemolysis assay on Wagatsuma agar. The highest TDH level achieved by the "TDH producer" was twofold lower than that of the Kanagawa phenomenon-positive strains as assayed by the RPLA method. All strains possessed the toxR gene. The trh1 and trh2 genes were detected in, respectively, 105 and 20 strains, and no correlation existed between the type of the trh gene and the levels of TDH produced. Considerable restriction fragment length polymorphism was observed with the tdh gene-bearing HindIII DNA fragment in different strains, but it was not related with the TDH level.

Interaction of divalent metal ions with Zn(2+)-glycerophosphocholine cholinephosphodiesterase from ox brain

The effect of divalent metal ions on the activity of glycerophosphocholine cholinephosphodiesterse from ox brain was examined. Zn(2+)- and Co(2+)-glycerophosphocholine cholinephosphodiesterases were prepared from the exposure of apoenzyme to Zn2+ and Co2+, respectively, and the properties of two metallo-phosphodiesterases were compared to those of native phosphodiesterase. Although two metallo-enzymes were similar in expressing Km value, optimum pH or sensitivity to Cu2+, they differed in the susceptibility to the inhibition by thiocholine or tellurite; while Co(2+)-phosphodiesterase was more sensitive to tellurites, Zn(2+)-phosphodiesterase was more susceptible to inhibition by thiocholine. In addition, Zn(2+)-phosphodiesterase was more thermo-stable than Co2+ enzyme. Separately, when properties of native phosphodiesterase were compared to those of each metallo-phosphodiesterase, native phosphodiesterase was found to be quite similar to Zn(2+)-phosphodiesterase in many respects. Even in thermo-stability, native enzyme resembled Zn(2+)-phosphodiesterase rather than Co(2+)-enzyme. Consistent with this, the stability of native phosphodiesterase was maintained in the presence of Zn2+, but not Co2+, Mn2+ was also as effective as Zn2+ in the stabilization of the enzyme. Noteworthy, the native enzyme was found to be inhibited competitively by Cu2+ with a Ki value of 20 microM, and its inhibitory action was antagonized effectively by Zn2+ or Co2+. Also, choline, another competitive inhibitor of the enzyme, appeared to antagonize the inhibitory action of Cu2+. Taken together, it is suggested that there may be multiple binding sites for divalent metal ions in the molecule of glycerophosphocholine cholinephosphodiesterase.

Heparin coating of vascular prostheses reduces thromboemboli

BACKGROUND

Synthetic conduits made from currently available materials are suboptimal for use in small-diameter vascular reconstruction because of their high surface thrombogenicity, which leads to failure.

METHODS

In this study control, heparin-irrigated, or heparin-bonded expanded polytetrafluoroethylene (ePTFE) grafts (4 mm long by 1 mm inner diameter) were implanted to reconstruct the iliac artery in male rats. The cremaster muscle was isolated as an island flap based on branches of the iliac artery downstream from the graft. Emboli were quantitated by using intravital fluorescent microscopy of the cremaster muscle's microcirculation.

RESULTS

The mean number of emboli observed per animal during a 20-minute period was 91 for the control group, 84 for the heparin-irrigated group, and 22 for the tridodecylmethylammonium chloride (TDMAC)-heparin group. The mean area of each embolus was 1057 microns 2 for control, 940 microns 2 for heparin-irrigated, and 808 microns 2 for TDMAC-heparin-coated grafts (p < 0.05 for TDMAC-heparin versus control or heparin-irrigated).

CONCLUSIONS

A TDMAC-heparin coating of ePTFE microvascular prostheses significantly reduces downstream microemboli.

Sustained release of antibiotic from a fibrin-gelatin-antibiotic mixture

To improve the therapeutic effect of antibiotics in the ear cavity postoperatively, a fibrin- and gelatin-based drug delivery system was designed and in vitro efficacy was evaluated. Four kinds of fibrin clot were made from ampicillin, gentamicin, and ofloxacin, and biologic assay was performed using Bacillus subtilis. The fibrin-gelatin-gentamicin mixture demonstrated antibiotic activity for up to 120 hours against B subtilis. Gentamicin was found to be released more slowly from the fibrin-gelatin mixture than from the fibrin mixture in this experiment. These results suggest that this device can be clinically used in a limited field such as postoperative care of ear infection.

Phenotype of porcine monocytic cells: modulation of surface molecule expression upon monocyte differentiation into macrophages

When porcine blood monocytes differentiate in vitro into macrophages, their morphology, as well as side scatter and forward scatter measured by flow cytometry, changed in a manner similar to that with human cells. During this differentiation, the initial high expression of CD molecules on porcine monocytes was down-regulated, with one exception--SWC9. Freshly isolated blood monocytes were SWC9-, but after culture the cells had become SWC9+. Thus, porcine monocytes were characterised as SWC3+SWC9-CD14high; macrophages were SWC3+SWC9+CD14low, the latter also displaying a down-regulation of CD11a/18, and, to a lesser degree, CD44. Both SWC9-CD14high monocytes and SWC9+CD14low macrophages were identifiable in freshly prepared monocytic cells from the spleen. Alveolar macrophages, on the other hand, were dominated by SWC9+CD14low cells, similar in phenotype to in vitro monocyte-derived macrophages. The consequences which these results have for studies on virus infections of porcine monocytic cells are discussed.

Note: purification of amylase secreted from Bifidobacterium adolescentis

Bifidobacterium adolescentis Int-57 isolated from human faeces produced extracellular amylase. The enzyme was purified from the culture supernatant fluids by ammonium sulphate precipitation, gel-filtration chromatography (Sephadex-G-75), ion-exchange chromatography (CM-cellulose) and FPLC. SDS-PAGE of the purified enzyme revealed a major band with an apparent molecular weight of 66 kDa. The pI was 5.2. Enzyme activity was optimal at 50 degrees C, and at pH 5.5. The enzyme was stable at 20-40 degrees C, and at pH 5-6 with a K(m) value of 2.4 g l-1 soluble starch. The activation energy was 42.3 kJ mol-1. The enzyme was significantly inhibited by maltose (10%), glucose (10%), Cu2+ (5 mmol l-1), Zn2+ (5 mmol l-1), N-bromosuccinimide (5 mmol l-1), EDTA (5 mmol l-1), I2 (1 mmol l-1) and activated by beta-mercaptoethanol (10 mmol l-1).

A role of nitric oxide in organophosphate-induced convulsions

The effects of nitric oxide-regulating compounds on convulsions and mortality of rats administered i.p. with diisopropylfluorophosphate was investigated. l-N(G)-nitroarginine methyl ester, a nitric oxide synthase inhibitor possessing an anticholinergic action, markedly attenuated the intensity of convulsions and significantly reduced the mortality rate. A similar result was obtained with anticholinergic procyclidine, an N-methyl-d-aspartate receptor antagonist. Noteworthy, l-N(G)-nitroarginine, another inhibitor of nitric oxide synthase, significantly attenuated the seizure intensity when administered in combination with atropine sulfate (5 mg/kg), though either l-N(G)-nitroarginine or atropine sulfate was inactive alone. It is suggested that nitric oxide may be a proconvulsant or a convulsion-promoting factor in anticholinesterase poisoning, and both the reduction of nitric oxide level and blockade of cholinergic systems may be required for more effective protection of seizures.

Helicobacter pylori infection and the risk of gastric cancer among the Korean population

Helicobacter pylori infection has been associated with chronic atrophic gastritis, a precursor of gastric cancer. We conducted a prospective, case-controlled study to investigate whether H. pylori infection increases the risk of gastric cancer in Korean people with a high risk of gastric cancer. We enrolled 160 gastric cancer patients who were confirmed by endoscopic biopsy during 1994 and 160 age-matched control subjects with non-ulcer dyspepsia were compared to document the relationship between H. pylori infection and gastric cancer. The presence of H. pylori infection was determined by the rapid urease test and/or histology by Wright-Giemsa staining. The overall presence of H. pylori infection was 60% in gastric cancer patients and 51.9% in age-matched control subjects (odds ratio 1.39; 95% confidence interval 0.894-2.17; P = 0.143). Carcinomas of cardia, body and antrum were not associated with H. pylori infection (odds ratio 1.43, 1.69 and 1.29, respectively; 95% confidence interval, 0.271-7.52, 0.787-3.62 and 0.689-2.43, respectively; P = 0.178, 0.177 and 0.642, respectively) nor was the intestinal or diffuse type of cancer (odds ratio 1.39 and 1.40, respectively; 95% confidence interval 0.791-2.45 and 0.681-2.87, respectively; P = 0.250 and 0.835, respectively). Gender was not a risk for gastric cancer. In contrast to previous studies, these results do not provide evidence of H. pylori infection for gastric carcinogenesis in Korea.

Progestin alone as primary treatment of endometrial carcinoma in premenopausal women. Report of seven cases and review of the literature

BACKGROUND

The standard treatment for endometrial carcinoma is staging laparotomy with total abdominal hysterectomy and bilateral salpingo-oophorectomy. In an attempt to preserve childbearing potential, selected patients with endometrial carcinoma were treated with progestin alone as primary therapy.

METHODS

Patients were identified through searches of tumor registries and solicitation of consulting gynecologic oncologists at the affiliated institutions of the University of California-Los Angeles Center for the Health Sciences. Only those patients with a diagnosis of endometrial carcinoma treated with progestin alone as primary therapy were included in the study. Independent pathologic review was performed by a recognized expert gynecologic pathologist to exclude cases of endometrial hyperplasia. A MEDLINE search was conducted to identify reports of similarly treated patients.

RESULTS

Seven patients were treated with progestin alone for endometrial carcinoma at the study institution. Fourteen additional patients were identified through the literature search. Combining the data for all patients, 13 of 21 patients (62%) had an initial response to progestins. Three initial responders later developed recurrent disease, one of whom was found to have extrauterine disease at laparotomy. Eight of 21 patients (38%) did not respond to progestins and underwent more definitive treatment. None of these patients later developed recurrent disease. Six viable infants were delivered of three patients after therapy. Nineteen of 21 patients were alive without evidence of disease at last follow-up.

CONCLUSIONS

The results of this study show that premenopausal women with endometrial carcinoma may be treated successfully with progestin therapy alone as primary therapy to preserve childbearing potential.

Viral loads and E2/NS1 region sequences of hepatitis C virus in hepatocellular carcinoma and surrounding liver

OBJECTIVES

Numerous epidemiologic data have documented that chronic infection by hepatitis C virus (HCV) is a major risk factor for the development of hepatocellular carcinoma (HCC). But the molecular mechanism underlying these strong epidemiologic associations between HCV and HCC has not be elucidated. We observed the changes of HCV in HCC to investigate the association of HCV with HCC.

METHODS

We used competitive and quantitative polymerase chain reaction and dideoxy-nucleotide chain termination method to compare HCV titers and sequences of the hypervariable region of E2/NS1 region of four isolates from the HCC and surrounding cirrhotic liver tissues in tow anti-HCV positive patients.

RESULTS

The copy numbers of HCV-RNA were 1 x 10(6) and 4 x 10(6)/gm wet weight of HCC, and 8 x 10(7) and 3.2 x 10(8)/gm wet weight of cirrhotic liver tissues from patient-1 and -2. The sequence differences between HCV RNA in HCC and in cirrhotic liver were two and five nucleotides in patient-1 and in patient-2 respectively. The amino acid sequences were changed in one and two site in each patient.

CONCLUSION

These findings may suggest the possible etiological role of HCV in carcinogenesis of HCC, but complete sequence analysis of HCV including multiple isolates in the same patient, should be performed in many cases.

Adhesion formation after incisional hernia repair: a randomized porcine trial

Adhesion formation involving intraperitoneal contents is a significant complication of incisional hernia repair. We evaluated the rate of peritoneal adhesion formation following closure of experimentally induced large ventral fascial defects using selected synthetic prosthetic materials in a well standardized porcine model. Sixty 25 kg hogs had a 4 x 6 cm ventral fascial defect induced and were randomized to repair with either interrupted 0-Prolene suture, Marlex surgical mesh (Mx), GoreTex Dual Mesh (Gore-DM), or an experimental version of the latter having multiple 0.4 mm fenestrations (Gore-DMH). Mx mesh induced significantly more adhesions than did Gore-DM when the two materials were placed in a comparable manner (P < 0.001). Those animals whose defects were closed primarily with Prolene suture alone developed significantly fewer adhesions than either Mx or Gore-DM (with or without holes) when these materials were sutured in an overlaying (i.e., extraperitoneal) manner (Mx, P < 0.0001; Gore-DM, P < 0.05; Gore-DMH, P < 0.01). The intraperitoneal placement of the Gore-DM materials (i.e., underlay manner) resulted in a rate of adhesion formation that was not statistically different from that induced by closure with Prolene alone (P = 0.08 for Gore-DM and P = 0.07 for Gore-DMH). Our findings support the use of Gore-DM biomaterial as the preferred material in the repair of large abdominal fascial defects when the use of a synthetic prosthetic material is necessitated by the defect size.

Effects of calmodulin antagonists and anesthetics on the skin lesions induced by 2-chloroethylethyl sulfide

The effects of calmodulin antagonists and anesthetics on the skin lesions induced by an alkylating vesicant, 2-chloroethylethyl sulfide, were investigated using female hairless mice. 2-Chloroethylethyl sulfide, topically applied (0.6 microliter/5 mm in diameter) on the back skin of hairless mice, induced mild to moderate petechiae on the 1st day, and ulcers with a thick scab after 3 days. The healing process started after 6 days, resulting in shedding of scabs on 9.52 days. Water-soluble ointment bases showed some beneficial effects, whereas oily bases made the skin lesions worse. Trifluoperazine (0.5-1%) and thioridazine (2%), potent calmodulin antagonists, in Pluronic F-127 base substantially prevented the development of 2-chloroethylethyl sulfide-induced skin lesions. A similar effect was achieved with pentamidine (10%), another type of calmodulin antagonist, but not with ketoconazole, a weak calmodulin antagonist. In addition, anesthetics, such as lidocaine and pentobarbital, showed some protection, although at high concentrations (> 5%). As judged by the microscopic appearance, trifluoperazine successfully reduced the hemorrhage and the infiltration of inflammatory cells in early skin lesions, and the formation of thick scabs, which leads to granulomatous scar tissue in late lesions. These results suggest that some calmodulin antagonists and anesthetics in water-soluble bases might be a choice for the treatment of 2-chloroethylethyl sulfide-induced skin burns.

Adenosine transport inhibition ameliorates postischemic hypoperfusion in pigs

Cerebral ischemia is often followed by a period of delayed hypoperfusion that may contribute to tissue injury. We tested the hypothesis that augmentation of interstitial adenosine can improve tissue perfusion under this condition 10 min global ischemia was produced in two groups of isoflurane-anesthetized newborn pigs by occlusion of subclavian and brachiocephalic arteries, and changes in local cortical blood flow and cortical interstitial purine metabolites were measured using the combined hydrogen clearance-microdialysis technique. In one group, the dialysis probe was perfused with artificial cerebrospinal fluid buffer containing nitrobenzyl-thioinosine (NBT1, 100 mumol/l), a competitive inhibitor of adenosine transport. In the untreated group (n = 9), baseline cortical blood flow (39 +/- 3 ml/min/100 g) was depressed by 51 +/- 5% and 42 +/- 6% at 40 and 60 min, respectively, of postischemic reperfusion. NBTI increased baseline interstitial adenosine levels 2.4-fold which increased baseline cortical blood flow 1.5-fold to 60 +/- 4 ml/min/100 g, and increased both absolute adenosine levels as well as adenosine as a percentage of total purine metabolites throughout ischemia and reperfusion. As a result, the extent of postischemic hypoperfusion was significantly lessened in NBTI-treated animals (n = 9), with reductions in cortical blood flow of only 28 +/- 3% and 24 +/- 5% at 40 and 60 min of reperfusion, respectively. These results indicate that inhibition of adenosine transport by NBTI elevates interstitial adenosine concentration during and following cerebral ischemia, and concomitantly improves cortical perfusion in the post-ischemic period. The latter effect may contribute to the documented neuroprotective efficacy of adenosinergic therapy in cerebral ischemia.