Trp64Arg polymorphism of the beta 3-adrenergic receptor gene is associated with increased plasma leptin levels in obese Chinese women

BACKGROUND

beta 3-Adrenergic receptors are predominantly expressed in the fat cells of visceral adipose tissue in humans. They mediate catecholamine-induced lipolysis and thermogenesis of adipose tissue, which are important for the regulation of energy expenditure and, therefore, body weight. Recently, a Trp64Arg polymorphism of the beta 3-adrenergic receptor gene was reported to be associated with obesity and obesity-related metabolic complications in some ethnic populations. Leptin, a protein secreted by adipocytes, is proposed as a signal linkage between the central nervous system and peripheral fat storage. It has been shown in rodents that leptin may activate the sympathetic nervous system and, thus, beta 3-adrenergic receptors in adipose tissue. However, little is known about the relationship between the Trp64Arg polymorphism and plasma leptin in humans.

METHODS

To determine the effects of the beta 3-adrenergic receptor gene Trp64Arg mutation on anthropometric measures, metabolic parameters and plasma leptin levels, 188 premenopausal Chinese women (mean age +/- standard deviation, 32 +/- 10 years) with body mass index (BMI) between 16.1 and 59.8 kg/m2 were investigated. Trp64Arg polymorphism was determined by DNA analysis, body fat mass by bioelectric impedance analysis and plasma leptin by radioimmunoassay.

RESULTS

Trp64Arg allele frequency was 15% in this population and there was no homozygous Arg64Arg mutant. When the subjects were divided into three groups based on BMI values (BMI < 22.2, n = 60; 22.2 < or = BMI < or = 29.5, n = 63; BMI > 29.5 kg/m2, n = 65), there was no difference in Trp64Arg allele frequency (16% vs 11% vs 18%, p = 0.149). Across the three groups, plasma leptin correlated positively with BMI (r = 0.843, p < 0.0001) and total fat mass (r = 0.824, p < 0.0001). Within each BMI tertile, the waist to hip ratio, fat mass, plasma lipids, glucose and insulin were relatively similar between Trp64Trp homozygotes and Trp64Arg heterozygotes. However, Trp64Arg heterozygotes had higher plasma leptin levels than Trp64Trp homozygotes (35.9 +/- 11.0 vs 30.0 +/- 12.8 ng/ml, p = 0.0023) in those with BMI above 29.5 kg/m2, a difference which remained after adjustment for body fat mass (p = 0.024).

CONCLUSIONS

Trp64Arg polymorphism of the beta 3-adrenergic receptor gene is not associated with obesity in Chinese women. Plasma leptin concentrations correlate well with BMI and total fat mass. For obese Chinese women, the Trp64Arg genotype of the beta 3-adrenergic receptor gene may contribute to an increased plasma leptin level.

Gastrocolic fistula due to adenocarcinoma of the colon: simulation of primary gastric leiomyosarcoma on CT

This article describes the CT findings in two patients with adenocarcinoma of the colon and gastrocolic fistula which simulated the classic appearance of gastric leiomyosarcoma on CT. The role of CT in the diagnosis of gastrocolic fistula is also discussed.

High plasma leptin concentrations in hypertensive men but not in hypertensive women

OBJECTIVE

Previous studies on humans have reported higher leptin levels in women than in men, independent of body fat, and leptin has been correlated with insulin resistance in men but not in women. Since insulin resistance is thought to play a role in raising blood pressure, we investigated sex differences in leptin concentrations between hypertensive and normotensive individuals.

METHODS

Ninety-two nondiabetic hypertensive patients (48 men and 44 women) and 92 age, body mass index (BMI)-matched normotensive control individuals were studied. Fasting plasma glucose, insulin, leptin and lipoprotein concentrations, glucose and insulin responses to 75 g oral glucose tolerance test (OGTT) and insulin suppression tests were determined.

RESULTS

Fasting plasma leptin concentrations were higher in hypertensive men than in normotensive men (5.1 +/- 0.5 versus 3.9 +/- 0.4 ng/ml, P = 0.015). However, fasting plasma leptin concentrations were not significantly different between hypertensive and normotensive women (11.8 +/- 1.0 versus 10.9 +/- 1.0 ng/ml, P = 0.440). Fasting plasma leptin concentrations showed good correlation with BMI, body fat, fasting plasma insulin concentrations, and insulin area to OGTT in both men and women (all P < 0.001). However, fasting plasma leptin concentrations were related to steady-state plasma glucose (SSPG) concentrations, a measure of insulin sensitivity by insulin suppression test, in men only (P < 0.001). After adjustment for body fat amount, age and duration of hypertension, fasting plasma leptin levels still correlated significantly with SSPG concentrations in men. These four variables together accounted for a 67.9% variation in fasting plasma leptin levels in men. In women, body fat amount was the only significant determinant for plasma leptin levels. These four variables accounted for a 78.2% variation in plasma leptin levels in women.

CONCLUSIONS

Our study confirmed a sex difference in leptin levels both in hypertensive and normotensive subjects. Higher plasma leptin concentrations in hypertensive men but not in hypertensive women when compared with normotensive control individuals was also demonstrated. These observations are consistent with the findings that plasma leptin is correlated with insulin sensitivity in men but not in women. Further studies are needed to understand the causes and consequences of sex effects on leptin in blood pressure regulation.

Spatial and temporal expression of UDP-galactose: ceramide galactosyl transferase mRNA during rat brain development

We studied the expression of UDP-galactose: ceramide galactosyl transferase (CGT) mRNA in postnatal rat brains using an in situ hybridization technique. From P0 to P16, there was a defined temporal and spatial pattern to the earliest acquisition of CGT mRNA expression. In the forebrain, CGT mRNA-expressing (CGT+) cells were first detected in regions outside the subventricular zone around the lateral ventricle at P2. Cells in the external capsule, internal capsule and corpus callosum were later found to be CGT-positive. At P8 to P16, CGT+ cells were found in the thalamus, striatum, occipital and frontal cortex. In the case of midbrain and hindbrain, the first CGT+ signals were detected in the medullary raphe of the medulla oblongata at P0. CGT+ cells were subsequently located in the cerebellum, midbrain and pons from P4 to P16. That is, in regions closer to the areas in which CGT+ cells were first found, CGT mRNA expression was observed much earlier. These findings support the notion that there are at least two discrete waves of CGT mRNA signal expression in the forebrain and hindbrain.

Expression of brain-derived neurotrophic factor in catecholaminergic neurons of the rat lower brainstem after colchicine treatment or hemorrhage

Widespread brain-derived neurotrophic factor messenger RNA expression has been detected in the region of catecholamine groups of the rat lower brainstem, while few brain-derived neurotrophic factor-immunoreactive cells were found in this area. In the present study, a double-color immunofluorescence technique for brain-derived neurotrophic factor and tyrosine hydroxylase after colchicine treatment was employed to evaluate the possible presence of brain-derived neurotrophic factor immunoreactivity in the catecholaminergic cells of the rat lower brainstem. We detected many new brain-derived neurotrophic factor-immunoreactive cells in the A1, A2, A4, A6-A10 and C1-C3 cell groups and in the other lower brainstem nuclei where, without colchicine treatment, brain-derived neurotrophic factor messenger RNA was expressed, but not brain-derived neurotrophic factor immunoreactivity. In addition, the catecholaminergic neurons were found to express brain-derived neurotrophic factor immunoreactivity with the co-existence being greatest, in percentage terms, in medullary catecholaminergic cell groups. Hypotensive hemorrhage, which activates medullary catecholaminergic neurons, induced the expression of brain-derived neurotrophic factor immunoreactivity in catecholaminergic neurons (A1/C1 and C2). The results demonstrate that brain-derived neurotrophic factor is regulated by neuronal activity in medullary catecholaminergic cell groups involved in central cardiovascular regulation.

In situ localization of neuronal nitric oxide synthase (nNOS) mRNA in the rat retina

We performed a comparative study on the distribution of neuronal nitric oxide synthase (nNOS) immunoreactivity and mRNA in a normal rat retina using immunocytochemistry and in situ hybridization technique. As in previous studies, we found NOS immunoreactive (NOS-IR) cells and fibers in inner and outer plexiform layers (IPL and OPL), inner nuclear layer (INL) and inner photoreceptor segment (IPS). However, very little nNOS-IR could be detected in groups of amacrine cells and ganglion cells localized in ganglion cell layer (GCL). However, in situ hybridization showed that intense NOS mRNA signals were mainly found in the GCL and INL while weak or no mRNA signals were detected in IPL, OPL, outer nuclear layer (ONL) and IPS. This difference suggests that nNOS proteins may be transported through axons into the terminals in the IPL and OPL after they were synthesized with nNOS mRNA templates in the INL. In the case of nNOS mRNA in GCL, synthesizing nNOS proteins may move outside the eyeball and carry out tasks in central nervous system. The difference of nNOS mRNA and nNOS IR means that the complete concurrence of nNOS IR and in situ hybridization results may not always occur in the rat retina.

Low-grade gastric mucosa-associated lymphoid tissue lymphoma: correlation of radiographic and pathologic findings

PURPOSE

To describe upper gastrointestinal (Gl) examination findings of low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to correlate them with pathologic examination findings.

MATERIALS AND METHODS

A retrospective review of upper Gl examinations was performed in 25 patients with proved low-grade gastric MALT lymphomas. Upper Gl examinations were reviewed for common findings and most probable diagnosis, and these findings were correlated with pathologic findings in resected specimens in 15 patients.

RESULTS

The common findings at upper Gl examination included mucosal nodularity (n = 13), ulcer (n = 12), rugal thickening (n = 6), mass (n = 4), and enlarged areae gastricae (n = 2). The most probable diagnoses were early gastric carcinoma (n = 7), advanced gastric carcinoma (n = 6), gastritis (n = 9), and lymphoma (n = 3). Of 17 lesions found on resected specimens, six ulcers and two masses were not depicted at barium study. Disorganized convergent rugae projecting to multiple points and vague ulcer margins were present in four and seven lesions, respectively. Multiple ulcers were seen in two patients.

CONCLUSION

Although the common radiographic and pathologic findings observed in low-grade gastric MALT lymphomas were similar to those of gastric carcinomas or gastritis, disorganized convergent rugae, vague ulcer margins, and multiplicity of lesions may be helpful in differentiating them from gastric carcinomas or gastritis.

Gender differences in relation to leptin concentration and insulin sensitivity in nondiabetic Chinese subjects

OBJECTIVE

To investigate the relationship between fasting plasma leptin concentrations and insulin resistance in Chinese men and women.

DESIGN

Cross-sectional study design.

SUBJECTS

Ninety-six nondiabetic Chinese (51 men and 45 women) with body mass index (BMI) between 18.4-35.8 kg/m2 were studied.

MEASUREMENTS

Plasma glucose and insulin concentrations were measured every 30 min for 2 h after a 75 g oral glucose load. The degree of insulin resistance was assessed using a modified insulin suppression test. Plasma leptin values were determined by radioimmunoassay.

RESULTS

Fasting plasma glucose, glucose areas, fasting insulin, insulin areas, most of the lipoprotein concentrations and steady state plasma glucose (SSPG) concentrations were relatively similar between men and women. Despite the fact that men had higher BMI values (26.1 +/- 0.5 vs 24.7 +/- 0.5 kg/m2, P < 0.05), fasting plasma leptin concentrations were significantly lower in men than in women (4.9 +/- 0.5 vs 9.0 +/- 0.8 ng/ml, P < 0.001). Fasting leptin values were positively related to SSPG concentrations by simple correlation analysis in both sexes. However, this relationship persisted in men (r = 0.513, P < 0.01) but not in women (r = 0.119, P = NS) after adjustment for BMI. Multiple regression analysis showed that SSPG concentrations, BMI, glucose and insulin responses together accounted for 62.5% and 52.2% of the variation in plasma leptin concentrations in Chinese men and women respectively.

CONCLUSION

Fasting plasma leptin concentrations were lower in Chinese men than in Chinese women despite the higher BMI observed in men. After adjustment for BMI, plasma leptin values correlated with the degree of insulin resistance in men but not in women.

Improved fluorescent determination method of cellular sphingoid bases in high-performance liquid chromatography

Precolumn orthophthaldehyde (OPA) labeling method of sphingoid bases, sphingosine and sphinganine, was investigated to obtain high fluorescent detectability. In order to improve the fluorescent yield, we investigated the optimal solubility of sphingoid bases for five pre-incubation solvents by incorporating the heating procedure before OPA derivatization. The pre-incubation in ethanol prominently increased the fluorescent peak height of OPA derivative for each sphingoid bases in high performance liquid chromatography. About ten-fold increase of detectability was archived by pre-incubating lipid extracts pellets in ethanol at 60 degrees C for 30 min. Optimal derivatization was performed in 30 min at ambient temperature and the fluorescent intensity of OPA derivative was stable for two weeks at 4 degrees C. The detection limit of sphingosine was 0.1 pmol as injected amount. This method was applied to the determination of cellular sphingosine and sphinganine in various human lung cancer cells. This OPA procedure was prospective to be useful for quantitating the amount of sphingoid bases in other cancer cells.

Constitutive activation of extracellular signal-regulated kinase in human acute leukemias: combined role of activation of MEK, hyperexpression of extracellular signal-regulated kinase, and downregulation of a phosphatase, PAC1

Extracellular signal-regulated kinase (ERK) is an important intermediate in signal transduction pathways that are initiated by many types of cell surface receptors. It is thought to play a pivotal role in integrating and transmitting transmembrane signals required for growth and differentiation. Constitutive activation of ERK in fibroblasts elicits oncogenic transformation, and recently, constitutive activation of ERK has been observed in some human malignancies, including acute leukemia. However, mechanisms underlying constitutive activation of ERK have not been well characterized. In this study, we examined the activation of ERK in 79 human acute leukemia samples and attempted to find factors contributing to constitutive ERK activation. First, we showed that ERK and MEK were constitutively activated in acute leukemias by in vitro kinase assay and immunoblot analysis. However, in only one half of the studied samples, the pattern of ERK activation was similar to that of MEK activation. Next, by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and immunoblot analysis, we showed hyperexpression of ERK in a majority of acute leukemias. In 17 of 26 cases (65.4%) analyzed by immunoblot, the pattern of ERK expression was similar to that of ERK activation. The fact of constitutive activation of ERK in acute leukemias suggested to us the possibility of an abnormal downregulation mechanism of ERK. Therefore, we examined PAC1, a specific ERK phosphatase predominantly expressed in hematopoietic tissue and known to be upregulated at the transcription level in response to ERK activation. Interestingly, in our study, PAC1 gene expression in acute leukemias showing constitutive ERK activation was significantly lower than that in unstimulated, normal bone marrow (BM) samples showing minimal or no ERK activation (P =.002). Also, a significant correlation was observed between PAC1 downregulation and phosphorylation of ERK in acute leukemias (P =.002). Finally, by further analysis of 26 cases, we showed that a complementary role of MEK activation, ERK hyperexpression, and PAC1 downregulation could contribute to determining the constitutive activation of ERK in acute leukemia. Our results suggest that ERK is constitutively activated in a majority of acute leukemias, and in addition to the activation of MEK, the hyperexpression of ERK and downregulation of PAC1 also contribute to constitutive ERK activation in acute leukemias.

Border malaria characters of reemerging vivax malaria in the Republic of Korea

Since 1993, the number of vivax malaria cases has increased every year in the northern part of the Republic of Korea (ROK). This study was designed to characterize factors related to the reemergence of malaria in the ROK. A total of 21 cases diagnosed in 1993 and 1994 distributed sporadically in the narrow zone along the demilitarized zone (DMZ). Of total 317 civilian inhabitant cases reported in 1994-1997, 287 cases were studied and 80.8% of them resided within 10 km from the southern border of the DMZ. The frequency distribution of anti-Plasmodium vivax antibody titers using indirect fluorescent antibody test was compared in three villages in relation with distance from the DMZ. The number of inhabitants with high antibody titers was larger in the village nearest to the border than that in more distant villages. The present results highly suggested that the reemerging vivax malaria start in the border area, most possibly caused by infected mosquitoes which flew across the border. This pattern of transmission repeated year after year.

Splanchnic arterial stenosis or occlusion: diagnosis at Doppler US

PURPOSE

To determine the diagnostic accuracy of Doppler ultrasonography (US) in the detection of high-grade stenosis or occlusion of the celiac artery (CA) and superior mesenteric artery (SMA) and validate the previously reported Doppler US criteria.

MATERIALS AND METHODS

During a recent 36-month period, 82 patients were prospectively examined with Doppler US of the splanchnic arteries and with lateral abdominal aortography, regardless of their abdominal symptoms. The previously reported diagnostic criteria with the fasting peak systolic velocity measurement were prospectively used in all patients. The results of Doppler US were compared with those of lateral aortography.

RESULTS

The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of Doppler US for the detection of 70% or greater CA stenosis or occlusion were 100%, 87%, 57%, 100%, and 89%, respectively; for 70% or greater SMA stenosis or occlusion, these values were 100%, 98%, 93%, 100%, and 99%, respectively.

CONCLUSION

Owing to its high accuracy in the diagnosis of high-grade splanchnic arterial stenosis or occlusion, Doppler US can be used as a screening method to help detect CA or SMA stenosis or occlusion and can reduce the use of unnecessary, invasive angiography.

Lack of association between genetic variation in the beta3-adrenergic receptor gene and insulin resistance in patients with coronary heart disease

The beta-adrenergic system plays a critical role in regulating lipolysis and thermogenesis. Recent studies have suggested that a missense Trp64Arg mutation in the beta3-adrenergic receptor gene is involved in visceral obesity and insulin resistance. We investigated the effect of this mutation on insulin resistance in patients with angiographically documented coronary heart disease ([CHD]n = 137) and normal subjects (n = 188). Plasma glucose and insulin responses to a 75-g oral glucose tolerance test and insulin resistance measured by the insulin suppression test, were determined in 58 (42%) patients with CHD and 121 (64%) controls. The genotype and allele frequency of the beta3-adrenergic receptor did not differ between patients with CHD and controls. The blood pressure, body mass index (BMI), waist to hip ratio, fasting plasma glucose, insulin, and lipid, and plasma glucose and insulin responses to the glucose load were relatively similar in subjects with and without the mutation in CHD and normal groups. The degree of insulin sensitivity, ie, the steady-state plasma glucose concentration, was not significantly different between subjects with and without the mutation in the CHD group (11.3 +/- 1.2, n = 11 v 11.9 +/- 0.6 mmol/L, n = 47, P = NS) and control group (8.4 +/- 0.7, n = 30 v 8.2 +/- 0.4 mmol/L, n = 91, P = NS). We conclude that Trp64Arg polymorphism of the beta3-adrenergic receptor gene does not likely play a major role in the development of CHD in the Chinese population. In addition, it appears to have no association with the insulin resistance syndrome in either CHD or non-CHD subjects.

Laparoscopic wedge resection of benign gastric tumor

BACKGROUND/AIMS

In the past 2 years, 9 patients diagnosed as benign gastric tumor pre-operatively underwent laparoscopic wedge resection of stomach at National Taiwan University Hospital. Among them, 6 were females and 3 were males.

METHODOLOGY

Histopathologically, 7 of 9 cases were of gastrointestinal stromal tumor (GIST). The clinical characteristics of this group were retrospectively reviewed and compared with another 12 cases of benign gastric tumor receiving open wedge resection in the same period.

RESULTS

There were no differences in sex, age, and pre-operative diagnosis in these two groups. It took a significantly longer operation time in the laparoscopic group than it did in the open group (205.71 vs. 97.5 min, p<0.05). However, the patients of the laparoscopic group started post-operative oral intake earlier (4.0 vs. 5.58 days, p<0.05), had shorter hospital stays (6.67 vs. 10.77 days, p<0.05), and lower analgesic usage rate (55% vs. 100%). There were no differences in operative complication rates.

CONCLUSIONS

Laparoscopic resection of benign-gastric tumor is recommended as a minimally invasive procedure.

Foci of eosinophil-related necrosis in the liver: imaging findings and correlation with eosinophilia

OBJECTIVE

The purpose of our study was to describe CT and sonographic findings of foci of eosinophil-related hepatic necrosis and to correlate those findings with eosinophil counts in the peripheral blood.

MATERIALS AND METHODS

We retrospectively reviewed 17 helical CT and 16 sonographic examinations (including follow-up examinations) in 10 patients with pathologically proven foci of eosinophil-related necrosis. Underlying causes were anisakiasis (n = 2), malignant neoplasms (n = 3), hypereosinophilic syndrome (n = 3), and idiopathic (n = 2). CT and sonographic images were reviewed by consensus by three radiologists, with an emphasis on the morphology and distribution of foci. Imaging findings were correlated with eosinophil counts in the peripheral blood.

RESULTS

All foci of eosinophil-related necrosis were observed as focal hypoattenuating lesions on all phases of helical CT and as focal hypoechoic lesions on sonography. Foci varied in size and were round or oval. The number of these foci seemed to be in proportion to the percentage of eosinophils in the peripheral blood. Most foci showed interval regression on follow-up CT or sonography as peripheral blood eosinophil counts decreased.

CONCLUSION

Foci of eosinophil-related necrosis cause focal hepatic lesions of varying size, shape, and number on helical CT and sonography. The number and extent of these foci were closely correlated to eosinophil counts in the peripheral blood.

Elevated plasma proinsulin/insulin ratio is a marker of reduced insulin secretory capacity in healthy young men

AIM

To examine whether reduced insulin secretory capacity or increased insulin secretory demand is associated with elevated ratio of plasma proinsulin to immunoreactive insulin (PI/IRI ratio) in non-diabetic subjects.

SUBJECTS AND METHODS

We measured various indices of insulin secretory function and insulin sensitivity by frequently sampled intravenous glucose tolerance test (FSIGT) and hyerglycemic glucose clamp in 21 healthy young men. We then examined the relationships between these indices and PI, IRI, or PI/IRI ratio in the fasting state.

RESULTS

Insulin sensitivity index (SI) measured by FSIGT correlated inversely with basal IRI (r=-0.53, P < 0.01) and PI levels (r=-0.57, P < 0.01), but there was no significant correlation between SI and PI/IRI ratio (r=0.26, NS). On the other hand, PI/IRI ratio correlated inversely with insulin secretory indices, such as acute insulin responses during FSIGT (r =-0.46, P < 0.01) and hyperglycemic glucose clamp (r=-0.54, P < 0.01) and submaximum insulin response during hyperglycemic glucose clamp (r=-0.59, P < 0.01).

CONCLUSIONS

These results indicate that elevated PI/IRI ratio may serve as a marker of reduced insulin secretory function in non-diabetic subjects.

Iodized oil retention due to postbiopsy arterioportal shunt: a false positive lesion in the investigation of hepatocellular carcinoma

BACKGROUND

Iodized-oil computed tomography (CT) is useful for the diagnosis of hepatocellular carcinoma, but there may be false-positive results in patients who have undergone some percutaneous transhepatic interventional procedures. The purpose of the present study was to verify the correlation between subsegmental hepatic parenchymal retention of iodized oil on CT and the arterioportal shunt caused by liver biopsy.

METHODS

Iodized-oil CT scans were reviewed in 24 patients with hepatic tumors who had liver biopsy and subsequent iodized oil chemoembolization. Iodized oil chemoembolization was performed shortly after biopsy (1-10 days; mean = 2.6 days). The results were correlated with hepatic arteriography, with a special emphasis on the presence of hepatic arterioportal shunt.

RESULTS

Wedge-shaped subsegmental retention of iodized oil along or adjacent to the biopsy needle path was observed in iodized-oil CT in 17 of the 24 patients. In three patients, there was subsegmental enhancement on prebiopsy helical dynamic liver CT at the same area of iodized oil retention, and therefore iodized oil retention was considered to be due to hepatocellular carcinoma. In the remaining 13 (54%) patients, the peripheral iodized oil retention was considered to be due to biopsy-induced arterioportal shunt. In all these patients, arterioportal shunt was confirmed by hepatic arteriography.

CONCLUSION

Wedge-shaped hepatic parenchymal retention of iodized oil is commonly observed in iodized-oil CT due to biopsy-induced arterioportal shunt, and this appearance should not be confused with a hepatocellular carcinoma.

Technology development in breath microanalysis for clinical diagnosis

A new generation of breath tests detects trace amounts of endogenous volatile organic compounds (VOCs) present in the breath. The breath microanalysis is potentially fast and convenient. It opens up a new promising area of using the breath test as a noninvasive diagnostic tool for a variety of diseases. Recent developments in microanalysis technology are expected to greatly facilitate the use of the breath test in clinical evaluations and applications, and these developments are described in the present review.

Plasma leptin concentrations are related to body fat mass and gender but not to thyroid dysfunction

Leptin, a newly defined protein synthesized and secreted from fat cells in both animals and humans, has gained wide attention. Many studies have been conducted on its roles in the regulation of body fat storage, energy expenditure and body weight changes. Thyroid dysfunction is known to have influences on the above changes in humans and these changes may in turn lead to a variation in circulating leptin levels. In addition, a sex dimorphism of plasma leptin levels has been a constant finding in many studies. However, the relationship between body fat mass and gender to plasma leptin levels in patients with various thyroid dysfunction has been rarely discussed together. A total of 134 patients with various thyroid function status were included in this study (hyperthyroidism: n = 50, hypothyroidism: n = 24, and euthyroidism: n = 60). Plasma leptin concentrations were compared between different thyroid function groups, and compared with body fat mass and body mass index (kg/m2) to check if these two parameters affect the circulating leptin levels. There were no significant differences between plasma leptin concentrations in the different thyroid function groups (Mean +/- SD: hyperthyroidism: 8.5 +/- 5.4 ng/ml, range: 1.5-25.8; hypothyroidism: 8.4 +/- 4.7 ng/ml, range: 1.8-20.1, and euthyroidism: 7.3 +/- 4.5 ng/ml, range: 0.6-20.9). Rather, a significant gender difference was found, with female subjects having two-fold higher levels than males when all study subjects were encompassed (female: 8.8 +/- 4.9 ng/ml, range: 11.7-25.8 vs male: 4.1 +/- 2.1 ng/ml, range 0.6-8.1, p < 0.001) or when thyroid function status was analyzed separately (hyperthyroidism: female: 9.7 +/- 5.5 ng/ml vs male: 4.3 +/- 2.1 ng/ml, p < 0.001; hypothyroidism: female: 9.7 +/- 4.6 ng/ml vs male: 4.4 +/- 2.4 ng/ml, p = 0.015; and euthyroidism: female: 7.9 +/- 4.5 ng/ml vs male: 3.6 +/- 1.9 ng/ml, p = 0.013). Plasma leptin concentrations had strong correlation with body fat mass in both females (r = 0.47, p < 0.001) and males (r = 0.71, p < 0.001). Good correlation was also observed between plasma leptin concentrations and body mass index in females (r = 0.51, p < 0.001) and males (r = 0.78, p < 0.001). Plasma leptin concentrations were not different in thyroid dysfunction. A significant gender difference existed and a positive correlation between body fat mass and BMI to plasma leptin was observed.

Assessment of pancreatic invasion in patients with advanced gastric carcinoma: usefulness of the sliding sign on sonograms

OBJECTIVE

The purpose of our study was to determine the value of the sliding sign on sonograms in evaluating direct pancreatic invasion of advanced gastric carcinoma.

SUBJECTS AND METHODS

Sonography was performed prospectively on 70 patients with pathologically proven advanced gastric carcinoma. Sonography was directed at the detection of motion between the gastric mass and the pancreas. When the gastric mass showed complete sliding motion against the pancreas or partial sliding motion with a preserved echogenic fat plane between the two organs on respiration or on extrinsic compression with a transducer (positive sliding sign), patients were considered to have no pancreatic invasion. When the gastric mass had no sliding motion against the pancreas or partial sliding motion with a disrupted echogenic fat plane between the two organs (negative sliding sign), patients were considered to have pancreatic invasion. After sonography, all patients underwent surgery and the results of sonography were compared with the findings at surgery and pathology.

RESULTS

Of the 70 patients, 17 had pancreatic invasion and 53 had no evidence of pancreatic invasion at surgery and pathology. The sliding sign on sonography yielded an 80% sensitivity, 96% specificity, and 90% accuracy for the diagnosis of pancreatic invasion.

CONCLUSION

Application of the sliding sign on sonography was simple and highly accurate in the diagnosis of pancreatic invasion by advanced gastric carcinoma. The sliding sign may prove useful in the preoperative detection of pancreatic invasion by gastric carcinoma when CT has been inconclusive.

Family aggregation and maternal inheritance of Chinese type 2 diabetes mellitus in Taiwan

BACKGROUND

Type 2 diabetes mellitus (DM) is a well-known familial disease, although the genetics of this complex condition remains unclear. Recent evidence suggests the significance of maternal inheritance. However, the pattern of family aggregation and the influence of other family relatives on the mode of transmission in Chinese patients with diabetes are lacking.

METHODS

We interviewed 449 patients (151 men and 298 women) with type 2 DM who were aged between 35 and 74 years with a mean age of 58 +/- 1 years in a referral hospital in central Taiwan. We recorded a detailed family history of diabetes for each patient.

RESULTS

Overall, 60% of diabetic patients had at least one diabetic family member. Among these index patients, 22.5% had a diabetic mother compared with 12.0% who had a diabetic father (p < 0.001). Approximately 29% of diabetic patients had at least one diabetic sister compared with 24% who had at least one diabetic brother (p = 0.13). A total of 27% of diabetic men had a diabetic mother, compared with 20% of diabetic women. Women with diabetes had more diabetic sisters than did diabetic men. In contrast, diabetic men had a significantly increased percentage of diabetic family members on the maternal side or paternal uncles or aunts than did diabetic women. The percentage of diabetic patients who had a diabetic mother decreased as their age increased. The maternal effect disappeared in the diabetic patients who were over 65 years old. Statistical differences between diabetic fathers and mothers were observed when DM was diagnosed in patients under 65 years of age.

CONCLUSIONS

We documented the presence of family aggregation and significant maternal inheritance in Chinese patients with type 2 DM in Taiwan. Further prospective study is needed to monitor the offspring of diabetic parents and other relatives in order to clarify the true mode of family aggregation and maternal transmission of type 2 DM.

Regression of ductus arteriosus aneurysm in a neonate demonstrated by three-dimensional computed tomography

We present a case of ductus arteriosus aneurysm in a neonate in whom the diagnosis was made by echocardiography, three-dimensional surface rendering computed tomography (CT) and was subsequently confirmed by angiography. Regression of aneurysm after indomethacin treatment was clearly demonstrated in a follow-up CT scan. To our knowledge, this is the first report of ductus arteriosus aneurysm and its regression detected by 3D surface rendering CT.

Regenerative nodules in liver cirrhosis: findings at CT during arterial portography and CT hepatic arteriography with histopathologic correlation

PURPOSE

To determine the appearance of regenerative nodules in patients with liver cirrhosis at computed tomography (CT) during arterial portography (CTAP) and CT hepatic arteriography (CTHA).

MATERIALS AND METHODS

CTAP and CTHA of the liver were performed in 28 consecutive patients with hepatocellular carcinoma (HCC) who were scheduled to undergo partial resection of the liver. Helical CTAP was performed after contrast material injection into the superior mesenteric artery followed by helical CTHA after contrast material injection into the hepatic artery. CT scans were analyzed for the presence of identifiable nodules and their size; results were correlated with gross and microscopic findings.

RESULTS

Resected livers showed cirrhosis in 20 patients, chronic hepatitis in four, and normal liver in four. Among the 20 patients with cirrhosis, regenerative nodules were demonstrated as enhancing 3-10 mm nodules surrounded by lower attenuation fibrous septa 0.8-1.5 mm thick at CTAP in seven patients and nonenhancing nodules of the same size surrounded by enhancing fibrous septa at CTHA in 15 patients. The degree of fibrosis determined the conspicuity of nodules.

CONCLUSION

Regenerative nodules in cirrhotic liver are visualized as enhancing nodules surrounded by lower attenuation thin septa at CTAP and nonenhancing nodules surrounded by enhancing fibrous septa at CTHA. CTHA is more sensitive than CTAP in depicting regenerative nodules (P < .005).

Combined use of mini-laparoscope and conventional laparoscope in laparoscopic cholecystectomy: preservation of minimal invasiveness

Mini-laparoscopic cholecystectomy using a 2-mm mini-laparoscope has been reported to be beneficial but technically difficult. This study attempted to evaluate the relative efficacy of a new method, which provides the benefits of both conventional and mini-laparoscopic cholecystectomy. From March 1997 to December 1997, 143 patients (49 men, 94 women, mean age 52.6 years, range 20-79), American Society of Anesthesiology (ASA) class I-II, underwent elective cholecystectomy by a combination of a 2-mm mini-laparoscope and 10-mm conventional laparoscope (combined lap-aroscopic cholecystectomy, C group) in National Taiwan University Hospital, Taipei, Taiwan. The entire procedure was done through four ports (one 11-mm port and three 2-mm ports). For comparison, records from 46 patients receiving mini-laparoscopic cholecystectomy (M group, 17 men, 29 women, mean age 49.0 years, range 26-76) and 139 patients receiving conventional laparoscopic cholecystectomy (L group, 47 men, 92 women, mean age 51.2 years, range 28-82) by the same operative team were included retrospectively. Mean operation time, time until first postoperative oral intake, dosage of analgesic, and postoperative hospital stay as well as possible complications were compared. No significant differences concerning the age, sex, and ASA classification were identified between all groups. The operative time of the C group (59.9 +/- 17.3 min, p = 0.420) but was significantly shorter than that of the M group (72.8 +/- 26.5 min, p < 0.001). No differences concerning the analgesic usage (0.5 +/- 0.8 unit vs. 0.4 +/- 0.7 unit, p = 0.372), postoperative oral intake (4.4 +/- 1.9 h vs. 3.3 +/- 2.3 h, p = 0.067), and postoperative hospital stay (1.7 +/- 0.7 days vs. 1.7 +/- 0.7 days, p = 0.941) were found between the C group and the M group. However, compared with the L group, analgesic usage (0.5 +/- 0.8 unit vs. 0.8 +/- 1.0 unit, p = 0.003) and time until first postoperative oral intake (4.4 +/- 1.9 h vs. 6.2 +/- 3.0 h, p < 0.001) were less, and the postoperative hospital stay (1.7 +/- 0.7 days vs. 2.0 +/- 0.9 days, p = 0.002) was significantly shorter in the C group. Combined use of the mini-laparoscope and the conventional laparoscope in cholecystectomy provides the benefits of both conventional laparoscopic and mini-laparoscopic cholecystectomy. It is easier to perform than cholecystectomy that uses the mini-laparoscope alone and results in a much smaller wound with less pain than conventional laparoscopic cholecystectomy. It is a feasible, safe procedure, and the minimal invasiveness of mini-laparoscopic cholecystectomy is preserved. It is an alternative way to deal with gallstone disease, especially for younger women, who tend to be more concerned about cosmetic outcome.

A study of the effect of suction drainage on microvascular anastomosis

The effect of suction drainage on the patency of microvascular anastomosis was evaluated in 20 rats. No anastomosed vessels were sucked into the suction drain. Histologic examination of the specimens showed normal healing of the endothelium across the anastomotic site and no evidence of thrombus formation. The results indicate that the suction pressure does not affect the patency of microvascular anastomosis.

Overexpression of p53 is not associated with drug resistance of gastric cancers to 5-fluorouracil-based systemic chemotherapy

BACKGROUND/AIMS

Recent in vitro evidence has strongly suggested that most anti-cancer drugs exert their cytotoxic effects via a p53-dependent apoptosis pathway. An intact p53 molecule appears to be a prerequisite for the cancer cells to be susceptible to these drugs. In this study, we specifically examined if overexpression of p53 may confer drug resistance on human gastric cancer.

METHODOLOGY

All patients were treated by an empirical HDFL regimen (weekly 24-hour infusion of 5-FU, 2,600 mg/m2 and leucovorin, 300 mg/m2) in a prospective phase II clinical trial. Among them, patients with adequate pre-chemotherapy gastric cancer tissues for immunohistochemical studies were selected for this study. A p53 DO7 monoclonal antibody was used to detect the overexpression of p53. The results were designated as "-" or "+" by the independent interpretation of two pathologists.

RESULTS

A total of 30 patients, 18 men and 12 women, with a median age of 61.5 years (range: 32-78 years), were studied. There were 15 responders and 15 non-responders to HDFL chemotherapy. The percentage of p53 overexpression with positive DO7 staining was 20.0% (6 out of 30). There were no significant differences in the pertinent clinicopathologic features between the patients with positive staining of p53 and the patients with negative staining of p53. Three out of 6 (50.0%) patients with positive staining of p53 and 12 out of 24 (50.0%) patients with negative staining of p53 responded to chemotherapy, respectively (p = 1.000 by Fisher's exact test).

CONCLUSIONS

Our data suggested that the overexpression of p53 does not predict drug resistance to 5-FU of human gastric cancer.

Current status of vivax malaria among civilians in Korea

A result of national malaria surveillance in Korean civilians was described. Since a case of indigenous vivax malaria was detected in 1993, a total of 2,198 cases was confirmed by blood smear up to 1997. Of them, 1,548 cases were soldiers serving in the demilitarized zone (DMZ), while 650 cases were civilians. Number of civilian cases was 3 in 1994, 19 in 1995, 71 in 1996, and 557 in 1997. Of them, 239 were ex-soldiers who discharged after military service in the prevalent areas such as Paju, Yonchon, Kimpo, Kangwha, Tongduchon in Kyonggi-do and Chorwon in Kangwon-do while 308 patients were civilian residents in the prevalent areas. Seventy-two patients, living nationwide, had a history of visiting the prevalent areas during transmission season. Only 32 civilian patients denied any relation with the prevalent areas. As a whole, a half of the civilian cases was diagnosed when living in non-prevalent areas. Male patients in their twenties was the highest in number. Annual parasite index is steadily elevated in residents living in the prevalent areas. Monthly incidence showed an unimodal distribution, forming a peak in August. Ex-soldiers exhibited a delayed incubation ranging from 153 to 452 days (279 +/- 41 days). The time required for diagnosis was shortened from 23.6 days in 1995 to 13.7 days in 1997. Although the current epidemic of vivax malaria started as a border malaria, it seems highly probable that vivax malaria is established in the local areas and responsible for at least a part of transmission.

Genetic analysis of the insulin receptor gene in Chinese patients with extreme insulin resistance

BACKGROUND

Many patients with extreme insulin resistance in combination with acanthosis nigricans are reported to have defective insulin receptor genes. Because acanthosis nigricans is commonly accompanied by severe hyperinsulinemia and obesity, and obesity is a major factor in insulin resistance, this study was initiated to assess the prevalence of mutations in the insulin receptor gene in Chinese patients with extreme insulin resistance defined by hyperinsulinemia, obesity and acanthosis nigricans.

METHODS

Exons 1-22 of the insulin receptor gene were amplified by polymerase chain reaction (PCR) by from genomic DNA from 13 young subjects with clinical and metabolic features of extreme insulin resistance. They were also screened for nucleotide variation using single-strand conformation polymorphism (SSCP) combined with nucleotide sequence analysis.

RESULTS

Variant SSCP patterns were detected in exons 1, 3, 6, 11, 12 and 17 of the insulin receptor gene. However, sequencing of amplified DNA fragments revealed that none of the variations were mutations. The SSCP variant in exon 1 was caused by a novel intron polymorphism (G-->T at position 13, 5' intron), while the SSCP variant in exon 12 was caused by a novel silent polymorphism Thr789 (ACG-->ACA). Variants in exons 3 and 17 corresponded to known silent polymorphisms: Gln276 (CAA-->CAG) and His1068 (CAC-->CAT), respectively. Another three variants in exons 3, 6 and 11 were also identified as known polymorphisms in the flanking introns. In addition, two alterations, a silent polymorphism Gly8 (GGA-->GGG) and a polymorphism in the 3' flanking intron (T-->G at position 74), were observed in exon 1 of the insulin receptor gene.

CONCLUSIONS

Although the prevalence of insulin receptor gene mutations in this Chinese study population might be underestimated because of the sensitivity of SSCP, these results suggest that mutations at the insulin receptor locus are uncommon in subjects with features of hyperinsulinemia, obesity and acanthosis nigricans.

Helicobacter pylori-seronegative gastric carcinoma: a subset of gastric carcinoma with distinct clinicopathologic features

BACKGROUND/AIMS

The frequent association of gastric atrophy and intestinal metaplasia in gastric cancer (GC) might preclude serologic detection of Helicobacter pylori (H. pylori) infection in GC. By using polymerase chain reaction (PCR) for detection, we would like to determine whether there exists a subset of genuinely H. pylori-negative GC patients, and whether they have distinct clinicopathologic features or not.

METHODOLOGY

IgG antibodies against H. pylori were determined by ELISA in sera, and H. pylori DNA was detected by PCR in resected gastric specimens from 160 GC patients. Clinicopathologic characteristics were then compared among group A: seropositive, group B: seronegative but PCR-positive, and group C: seronegative and PCR-negative.

RESULTS

Among 160 patients, 105 (65.6%) were classified as group A, 25 (15.6%) as group B, and 30 (18.8%) as group C. Group B patients were older and had more infiltrative tumor growth than group A. Group C had a significantly higher frequency of female predominance, and their cancers were of a more cardiac location and of the diffuse histologic subtype than those of groups A and B.

CONCLUSIONS

A significant portion (15.6%) was negative to ELISA but positive to PCR, suggesting that older ages and infiltrative tumor growth might preclude serologic detection of H. pylori infection by impairing humoral responses. Although the majority (81.2%) has a strong association with H. pylori infection, an H. pylori-negative subset indeed exists and has distinct clinicopathologic features, supporting that causes other than H. pylori infection are involved in GC carcinogenesis.

Effects of Aspergillus fumigatus culture filtrate on antifungal activity of human phagocytes in vitro

BACKGROUND

Aspergillus fumigatus can colonise the airways and the lungs with localised underlying conditions and occasionally invade the surrounding lung tissues even in subjects without systemic predisposing factors, presumably by escaping the local host defences. The aim of this study was to investigate the effects of A fumigatus culture filtrate (ACF) on the activities of human phagocytes--inhibition of germination of A fumigatus spores by alveolar macrophages (AMs) and hyphal damage by polymorphonuclear leucocytes (PMNs)--which are the critical host defences against A fumigatus.

METHODS

Spores were incubated with AMs at a ratio of 1:1 in a medium containing different concentrations of ACF for 10 hours at 37 degrees C. Spore germination was visualised with light microscopy and the inhibition rate was calculated. The percentage of hyphal damage caused by PMNs pretreated with various concentrations of ACF was measured by a colorimetric tetrazolium metabolic assay.

RESULTS

The inhibition rate of spore germination by AMs cultured with medium alone (control) was 90 (0.8)% whereas that by AMs cultured with the medium containing 10% ACF was significantly (p < 0.05) reduced to 41.7 (4.6)%. ACF suppressed the inhibition of spore germination in a dose dependent manner without altering the phagocytosing activity against the spores. The percentage of hyphal damage caused by PMNs pretreated with medium-199 (control) was 78.1 (2.3)% compared with 65.3 (2.8)% when PMNs were pretreated with 50% ACF (p < 0.05).

CONCLUSIONS

A fumigatus releases biologically active substance(s) which suppress the inhibition of spore germination by AMs and also suppress PMN mediated hyphal damage, and thus may contribute to the pathogenicity of this fungus.

Overexpression of p53 in different subtypes of intestinal metaplasia and gastric cancer

p53 immunostaining was evaluated in cancerous epithelia and adjacent intestinal metaplasia of 135 gastric cancer specimens. The differential p53 overexpression in different subtypes of intestinal metaplasia and gastric cancer suggests that type III intestinal metaplasia is the commonest lesion in dysplasia-carcinoma transition, particularly in the intestinal type of gastric cancer.

Effects of alkaline protease or restrictocin deficient mutants of Aspergillus fumigatus on human polymorphonuclear leukocytes

Several substances including proteases and restrictocin have been suggested as candidates for virulence determinants in invasive pulmonary aspergillosis. However, the roles of such substances are not well understood. This study compared the in vitro suppressive effects of Aspergillus fumigatus culture filtrates (ACFs), on the functions of human polymorphonuclear leukocytes (PMNLs), the principal cells in the host defence against aspergillus hyphae, from a clinically isolated wild-type and isogenic mutant strains which lack production of elastolytic alkaline protease (Alp) and/or restrictocin. ACFs were obtained by culturing conidia of each strain in Medium- 199 at 37 degrees C for 5 days. ACFs of the wild-type significantly (p<0.01) suppressed chemotaxis, superoxide anion (O2-) release and PMNL-mediated hyphal damage, compared with the control (Medium-199). ACFs of the mutant strains that lack Alp or restrictocin significantly (p<0.01) suppressed chemotaxis and O2(-)-release, but did not suppress hyphal damage, compared with the control. The wild-type significantly (p<0.01) suppressed chemotaxis of PMNLs compared with the mutant strains lacking Alp or restrictocin, whereas there were no significant differences in suppression of O2(-)-release and hyphal damage by PMNLs. ACF of a mutant strain that lacks both Alp and restrictocin had much less activity, but significantly (p<0.01) suppressed chemotaxis of PMNLs compared with the control. In conclusion, alkaline protease and restrictocin may play roles in the suppressive effect of Aspergillus fumigatus culture filtrates on the functions of human polymorphonuclear leukocytes. Other antiphagocytic substances produced by Aspergillus fumigatus remain to be identified.

Overexpression of p53 predicts shorter survival in diffuse type gastric cancer

BACKGROUND

It has been suggested that p53 plays an important part in gastric carcinogenesis but the data remain inconclusive.

METHODS

Alteration of the tumour suppressor gene p53 was prospectively investigated by immunohistochemistry in 168 primary gastric cancers.

RESULTS

Positive staining, indicative of gene mutations, was detected in 34 tumours (20.2 per cent). No correlation was observed between expression of p53 and various clinicopathological factors, including age, sex, tumour site, gross type, tumour size, depth of invasion, lymph node metastases, distant metastases, and tumour node metastasis stage. However, p53 overexpression was different between intestinal and diffuse type gastric cancer. Survival analysis revealed a significant survival disadvantage of p53 expression in diffuse type gastric cancer (P=0.039) but not in the intestinal type. Multivariate analysis of all 168 patients revealed that independent predictors of recurrent disease included age, invasion depth and nodal involvement but not p53 expression.

CONCLUSION

The presence of p53 overexpression may identify a subset of more aggressive tumours with a poor prognosis in diffuse type gastric cancer.

Engagement of CD99 induces up-regulation of TCR and MHC class I and II molecules on the surface of human thymocytes

CD99 is a cell surface molecule involved in the aggregation of lymphocytes and apoptosis of immature cortical thymocytes. Despite its high level expression on immature cortical thymocytes, the functional roles of this molecule during thymic selection are only now being elucidated. Examination of the effects of CD99 engagement on the expression kinetics of the TCR and MHC class I and II molecules, which are involved primarily in thymic positive selection, revealed a marked up-regulation of these proteins on the surface of immature thymocytes. This increase was the result of accelerated mobilization of molecules stored in cytosolic compartments to the plasma membrane, rather than increased RNA and protein synthesis. Confocal microscopic analysis revealed the changes in subcellular distribution of these molecules. When CD99 was engaged, TCR and MHC class I and II molecules were concentrated at the plasma membrane, particularly at cell-cell contact sites. The TCRlow subpopulation of immature double positive thymocytes was much more responsive to CD99-mediated up-regulation than was the TCRhigh population. These findings suggest that CD99-dependent up-regulation may have possible implication in positive selection during thymocyte ontogeny.

Angiotensinogen gene polymorphism is associated with insulin resistance in nondiabetic men with or without coronary heart disease

BACKGROUND

Variants of the angiotensinogen gene may increase the risk of having arterial hypertension and coronary heart disease (CHD), but their effect on insulin resistance remains unknown.

METHODS

We determined M235 and T174 allele status and fasting plasma glucose, insulin, and lipids values in nondiabetic men with CHD documented on angiography (n = 102) and in a control group (n = 145). Plasma glucose and insulin responses to 75 gm oral glucose tolerant test and insulin resistance as measured by an insulin suppression test were also carried out in 46 (45%) patients with CHD and in 73 (50%) members of a control group.

RESULTS

We found no association between M235T status and blood pressure, fasting plasma glucose, insulin, most of the lipids values, and insulin resistance in patients with CHD and normal subjects. Nevertheless, compared with individuals with homozygotes T174, subjects with heterozygotes T174M were associated with greater glucose and insulin response to the oral glucose tolerance test and insulin resistance indicated by higher steady state plasma glucose concentrations in patients with CHD (14.7+/-0.9 vs 11.3+/-0.7 mmol/L, p < 0.04). Similar findings were found in the control group, with higher steady-state plasma glucose values in individuals with heterozygotes T174M than in those with homozygotes T174 (10.1+/-1.4 vs 7.7+/-0.4 mmol/L, p < 0.05).

CONCLUSION

We suggest that the angiotensinogen T174M allele might be associated with insulin resistance in nondiabetic men with and without CHD.

An immunohistochemical study of E-cadherin expression with correlations to clinicopathological features in gastric cancer

BACKGROUND/AIMS

Reduced expression of E-cadherin leading to loss of cellular adhesion is crucial for cancer invasion and metastasis. The aim of this study is to investigate the role of E-cadherin in gastric tumorigenesis.

METHODOLOGY

Immunohistochemical expression of E-cadherin was analyzed and correlated with clinicopathological characteristics of 122 patients with gastric cancer.

RESULTS

Reduced E-cadherin expression was noted in 71 tumors (58.2%), while all normal epithelium showed a normal expression. Correlation of E-cadherin status to histological subtypes and growth patterns revealed a significantly higher frequency of reduced expression in diffuse type (46/60, 76.7%), advanced tumors (48/68, 70.6%) and stage III/IV (39/53, 73.6%) than that in intestinal type (25/62, 40.3%, p<0.0001), early tumors (23/54, 42.6%, p<0.005) and stage I/II (32/69, 46.4%, p<0.005) respectively. Moreover, abnormal expression was more frequent in tumors with positive lymph node metastasis (45/62, 72.6%), peritoneum seeding (10/11, 90.9%) and venous permeation (27/37, 73%) than that in tumors without lymph node metastasis (26/60, 43.3%, p<0.005), peritoneum seeding (61/111, 55.0%, p<0.05) and venous permeation (44/85, 51.8%, p<0.05). There is no statistical difference between E-cadherin expression and the status of perineural invasion or H. pylori infection. Analysis of survival for patients demonstrated that reduced E-cadherin expression was correlated with poor prognosis.

CONCLUSIONS

These data indicate that impaired expression of E-cadherin is an important characteristic of gastric cancer and contributes to histogenesis, tumor growth, metastasis and poor survival.

Advantages of laparoscopic splenectomy for splenomegaly due to hematologic diseases

Recent advancements in laparoscopic surgery have made laparoscopic splenectomy possible. We retrospectively compared the outcomes of laparoscopic versus open splenectomy in patients with idiopathic thrombocytopenic purpura (ITP) or beta-thalassemia. From July 1993 to July 1997, 52 patients (ITP, 43 cases; beta-thalassemia, 9 cases) underwent either laparoscopic (30 patients, 9 men, 21 women; average age, 36.9 years) or conventional open splenectomy (22 patients, 5 men, 17 women; average age, 34.3 years). The two groups were similar in terms of sex, age, diagnosis, duration of disease, preoperative platelet count, and spleen size. The mean surgical time, estimated amount of blood loss, duration of postoperative recovery, analgesic usage, and complications were compared between the two groups. Laparoscopic splenectomy was successful in 29 (97%) of the 30 patients. The mean surgical time in the laparoscopy group was longer than in the open splenectomy group (190.6 vs 113.9 minutes, p < 0.01). The laparoscopy group had earlier postoperative oral intake (15.2 vs 52.6 hours, p < 0.01), less usage of analgesics (meperidine 50 mg/unit, 1.1 vs 2.8 units, p < 0.01) and a shorter postoperative hospital stay (4.1 vs 6.8 days, p < 0.01). The estimated blood loss, incidence of accessory spleen, surgical complication rate, and recurrence rate of thrombocytopenia were similar in the two groups. Our findings show that laparoscopic splenectomy in patients with ITP or beta-thalassemia is as safe as the open approach. While laparoscopy required a longer surgical time, the recovery period was shorter, analgesic use was less, and physical discomfort was less severe.

Gastric cancer risk in relation to Helicobacter pylori infection and subtypes of intestinal metaplasia

Helicobacter pylori (H. pylori) infection and intestinal metaplasia (IM) are each associated with an increased risk of gastric cancer (GC). To explore further the influences of H. pylori and IM on GC, H. pylori and subtypes of IM were evaluated in 135 sex and age-matched case and control pairs. Odds ratios (ORs) with 95% confidence intervals of developing GC were calculated for each risk factor using multiple logistic regression analysis. ORs for H. pylori infection and IM were 2.43 (1.29-4.65) and 4.59 (2.58-8.16), respectively, and those for different IM subtypes gave values of 0.82 (0.28-2.36) for type I, 2.03 (0.95-4.34) for type II and 39.75 (14.34-110.2) for type III. Stratification analysis by histological subtype and stage of GC showed a particularly high OR for IM in intestinal type (12.8, 4.73-34.83) and early GC (6.40, 2.25-18.18). Our data indicate that both H. pylori and IM are related to GC risk. Type III IM is a more specific marker of premalignancy, with relevance, in particular, to the early and intestinal type of GC.

Fifteen years' experience with gastric partitioning for obesity treatment

Most reports derived from experiences in Western countries indicate that surgery offers the best hope for morbidly obese patients. We report our experience with gastric partitioning in 63 Chinese patients (17 men and 46 women) aged 14 to 42 years, whose preoperative excess weights ranged from 62.3% to 166.7% above their ideal body weight. Transverse stapling was performed in 30 patients treated before April 1983, while vertical stapling gastric partitioning with a window and a Marlex band to encircle the outlet tract was done in 33 patients after that. No patient died, but one had leakage at the anastomosis. Success was defined as a return to within 50% of the ideal body weight. Vertical-windowed gastric partitioning with a Marlex-banded outlet resulted in a significantly higher success rate than transverse stapling--70% vs 37%. Our experience suggests that vertical-windowed gastric partitioning with a Marlex-banded outlet is a safe and effective surgical treatment for morbidly obese Chinese people.

Relatively low expression of multidrug resistance-1 (MDR-1) and its possible clinical implication in gastric cancers

The mechanism of drug resistance of gastric cancer cells has rarely been investigated. We specifically examine the magnitude and the biologic significance of multidrug resistance-1 (MDR-1) expression in human gastric cancer. All patients had previously been treated in prospective clinical trials for advanced gastric cancer in our institution. Patients with adequate prechemotherapy gastric cancer tissues for immunohistochemical studies by a C219 monoclonal antibody were selected for the determination of the expression rate of MDR-1. The results were designated as negative or positive by the independent interpretation of two pathologists. A subgroup of patients who had been treated with doxorubicin- or etoposide-containing regimens were selected for further correlation with drug sensitivity. Between 1990 and 1996, a total of 60 patients, 38 men and 22 women with a median age of 55 years, were studied. Eight (13.3%; 95% confidence interval, 6%-25%) of them had MDR-1 expression. None of the pertinent clinicopathologic features, including the histopathologic types of the tumors and the extent of the diseases, correlated with the expression of MDR-1. Among the 30 patients who had received doxorubicin- or etoposide-containing combination chemotherapy, 3 (10%; 95% confidence interval, 3%-27%) were designated positive for MDR-1 expression. None of the 3 patients responded to chemotherapy, whereas 19 (70.4%) of the 27 patients who had not expressed MDR-1 did respond (p=0.041 by Fisher's exact test). We conclude that the expression of MDR-1 in gastric cancer is relatively low. Its expression, however, is clinically relevant and is useful in predicting the chemoresistance of patients with gastric cancer receiving doxorubicin- or etoposide-containing combination chemotherapy.

High expression of thymidylate synthase is associated with the drug resistance of gastric carcinoma to high dose 5-fluorouracil-based systemic chemotherapy

BACKGROUND

In the past 4 years, the weekly 24-hour infusion of high dose 5-fluorouracil (5-FU) and leucovorin in the treatment of patients with advanced gastric carcinoma has been prospectively studied at the authors' institution. This has enabled them to explore the possibility that the level of expression of thymidylate synthase (TS), the target enzyme of 5-FU, is related to the drug sensitivity of gastric carcinoma to 5-FU-based chemotherapy.

METHODS

To be eligible for this study, patients were required to have received high dose 5-FU and leucovorin chemotherapy (weekly 24-hour infusions of 5-FU, 2,600 mg/m2, and leucovorin, 300 mg/m2) and to have had adequate prechemotherapy gastric carcinoma tissues for immunohistochemical study. TS106 monoclonal antibody was used to detect the expression of TS. A visual scoring system, which ranged from 0 to 3+, was adopted by 2 independent pathologists to semiquantitate the intensity of TS expression.

RESULTS

Between 1993 and 1996, a total of 30 patients, 18 men and 12 women, with a median age of 61.5 years, were enrolled. Of these patients, 16 (53.3%) and 14 (46.7%) had high and low expression of TS, respectively. Two of the 16 patients (12.5%) with high expression of TS and 13 of the 14 patients (92.9%) with low expression of TS responded to chemotherapy (P < 0.001, chi-square test). The median overall survival was 10 months for patients with low TS expression and 4 months for patients with high TS expression (P < 0.01, log rank test).

CONCLUSIONS

The data from this study suggest that the expression of TS, as determined by immunohistochemistry, is a relatively reliable indicator of whether 5-FU should be used in the treatment of patients with gastric carcinoma.

Absence of a seasonal variation in myocardial infarction onset in a region without temperature extremes

To evaluate whether the incidence of acute myocardial infarction (AMI) attack would have circadian, weekly and monthly variations in a subtropical area, 540 consecutive patients with AMI who were admitted to our coronary care units were analyzed. Six-hour intervals over 24 h, daily intervals in a week (7 days) and monthly intervals in a year (12 months) were studied, respectively. Results showed that there was a circadian variation in the onset of AMI with a morning (6 a.m. to noon) peak (34%, p < 0.01) but no secondary late evening (18-24 p.m.) peak. The incidence of AMI was significantly lower on Sundays (9%) than on the other weekdays (Monday through Saturday; p < 0.05). However, no monthly and seasonal variations in the incidence of AMI (no winter or summer peaks) were observed in this series. This study demonstrated a circadian variation in the onset of AMI attack with a predominant morning peak. The fewer AMI cases on Sundays compared to the other weekdays suggested that freedom from 'stress' or 'work-load' on Sundays might have an important impact on this low incidence of AMI. Unlike the large ranges in cold or hot weather found in temperate regions, the warm climate of a subtropical region does not affect the frequency of AMI.

Mucocele of the appendix: ultrasonographic and CT findings

BACKGROUND

Mucocele of the appendix is a rare disease entity, but preoperative diagnosis is very important. With the advent of ultrasonography (US) and computed tomography (CT), it has been possible to preoperatively diagnose mucocele of the appendix. We describe the spectrum of US and CT findings of mucocele of the appendix and the differential points from mimicking diseases.

METHODS

We evaluated 17 patients with pathologically proven mucocele of the appendix by using US and CT. Pathologic diagnoses of 17 patients were mucinous cystadenoma in 11 patients, mucinous cystadenocarcinoma in two, and mucosal hyperplasia in four. We analyzed morphologic characteristics of mucocele of the appendix at US and CT.

RESULTS

The typical US finding were a cystic mass with variable internal echogenicity, layered wall, and calcification in the wall. The CT finding was a well-encapsulated cystic mass with a wall of variable thickness. Both cases with focal nodular solid enhancing portion in the wall on CT were pathologically proven as mucinous cystadenocarcinoma.

CONCLUSION

US and CT were useful methods in diagnosing mucocele of the appendix and differentiating this condition from mimicking diseases. Nodular enhancing lesion in the wall of the mucocele may be a finding suggestive of malignant cause of mucocele.

High expression of thymidylate synthase is associated with the drug resistance of gastric carcinoma to high dose 5-fluorouracil-based systemic chemotherapy

BACKGROUND

In the past 4 years, the weekly 24-hour infusion of high dose 5-fluorouracil (5-FU) and leucovorin in the treatment of patients with advanced gastric carcinoma has been prospectively studied at the authors' institution. This has enabled them to explore the possibility that the level of expression of thymidylate synthase (TS), the target enzyme of 5-FU, is related to the drug sensitivity of gastric carcinoma to 5-FU-based chemotherapy.

METHODS

To be eligible for this study, patients were required to have received high dose 5-FU and leucovorin chemotherapy (weekly 24-hour infusions of 5-FU, 2,600 mg/m2, and leucovorin, 300 mg/m2) and to have had adequate prechemotherapy gastric carcinoma tissues for immunohistochemical study. TS106 monoclonal antibody was used to detect the expression of TS. A visual scoring system, which ranged from 0 to 3+, was adopted by 2 independent pathologists to semiquantitate the intensity of TS expression.

RESULTS

Between 1993 and 1996, a total of 30 patients, 18 men and 12 women, with a median age of 61.5 years, were enrolled. Of these patients, 16 (53.3%) and 14 (46.7%) had high and low expression of TS, respectively. Two of the 16 patients (12.5%) with high expression of TS and 13 of the 14 patients (92.9%) with low expression of TS responded to chemotherapy (P < 0.001, chi-square test). The median overall survival was 10 months for patients with low TS expression and 4 months for patients with high TS expression (P < 0.01, log rank test).

CONCLUSIONS

The data from this study suggest that the expression of TS, as determined by immunohistochemistry, is a relatively reliable indicator of whether 5-FU should be used in the treatment of patients with gastric carcinoma.

Laparoscopic resection of a primary retroperitoneal mucinous cystadenoma: report of a case

Primary retroperitoneal mucinous cystic tumors are extremely rare, and although their histogenesis is still uncertain, several theories have been proposed. Traditionally, transabdominal laparotomy and enucleation of the cyst is the treatment of choice and laparoscopic resection has not previously been reported. This paper presents the case of a 48-year-old woman in whom a primary retroperitoneal cystic mass, 15 x 13 x 9 cm in size, was successfully resected through the laparoscope. Pathological examination revealed a mucinous cystadenoma with borderline malignancy. The patient had a prompt recovery and there was no evidence of recurrence at her 8-month follow-up. However, the prevention of cystic fluid spillage during laparoscopic manipulation is important, especially when the pathology of the retroperitoneal cyst is unclear.

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.

Effect of the gasoline additives on PAH emission

PAH emission from the powered engines fueled by a 95 leadfree gasoline (95-LFG), a 92 leadfree gasoline (92-LFG) and a Premium leaded gasoline (PLG) with two gasoline additives (SA and SB) were collected using a PAH sampling system with a particulate interception device. Twenty one PAHs were analyzed primarily by an GC/MS, while eight metal elements were determined mainly by an ICP-AES. This investigation showed that the gasoline additives contain more amounts of carcinogenic PAHs than gasolines do. Blending these additives do raise the PAH content in the gasolines, simultaneously, will emit more amount of PAHs from the tailpipe of engine exhaust. It is suggested that before a gasoline additive is commercialized, an assessment on its PAH emission should be evaluated to make sure that the additive will not emit more PAHs and cause adverse effect on public health.

Clinicopathological significance of altered loci of replication error and microsatellite instability-associated mutations in gastric cancer

Replication errors (RERs) judged by microsatellite instability and its associated mutations have been recognized as an important mechanism in tumorigenesis of gastric cancers (GCs). To gain a deeper insight into its significance, we examined the frequency of RERs using nine microsatellite markers and screened mutations in the polydeoxyadenine tract of the transforming growth factor beta type II receptor gene (TGF-betaRII) and polydeoxyguanine tracts of insulin-like growth factor II receptor and BAX genes. Twenty-four (30%) of 80 patients with GC had RERs, of which 3, 8, and 13 had one, two, and three or more loci, respectively. In 13 tumors with RERs in three or more loci, frameshift mutations of TGF-betaRII, insulin-like growth factor II receptor, and BAX were identified in 12, 3, and 2, respectively. Compared with GC with none, one or two RER-positive loci as a group, GC with RERs in three or more loci showed a significantly higher frequency of antral location (12 of 13 versus 35 of 67; P = 0.01), intestinal subtype (11 of 13 versus 30 of 67; P = 0.01), and previous Helicobacter pylori infection (12 of 13 versus 41 of 67; P = 0.05) and a lower incidence of lymph node metastasis (5 of 13 versus 49 of 67; P = 0.02) and tended to be in an advanced stage (12 of 13 versus 54 of 67; P = 0.28). These data indicate that GC with multiple RERs manifest distinct clinicopathological characteristics, and that a high frequency of frameshift mutations involving the TGF-betaRII gene may be causatively linked with tumorigenesis and progression.