[A survey on blood lipid levels among newborns and healthy inhabitants in urban Shanghai from 1997 to 1999]

OBJECTIVE

To analyze the blood lipid levels among inhabitants of different ages in urban Shanghai by the end of 1990 and compare the results with those in 1970 s and 1980 s.

METHODS

Venous blood samples were collected from 3647 persons undergoing annual health examination, including workers and staff members, employees, functionaries, and students of factories, governmental organizations, institutions, enterprises, and schools. Umbilical blood samples were collected from 88 newborns. Serum TC, TG, LDL-C, and HDL-C were determined.

RESULTS

3647 blood samples were collected in total. It is found that: (1) The levels of blood lipids increased along with the age. The levels of TC and LDL-C among females over their fifty were higher that those among the males in the same age groups. The level of TG among females over fifty was similar to that among the males in the same age groups. The levels of LDL-C were higher in families in all of the age groups than those in the males of the same ages. (2) In comparison to those in 1970 s the levels of TC and TG in 1990 s were significantly higher by 6.79% - 17.69% and 21.95% - 45.53% respectively, and the level of HDL-C decreased by 8.02% - 29.19%. (3) The percentage of persons over forty with their TC levels over the upper normal limit was much larger in 1990 s than in 1970 s (for TC 11.57% vs. 4.40% among males and 16.02% vs. 5.40% among females, for TG 21.83% vs. 5.20% among males and 13.32% vs. 5.70% among females). and (4) The percentage of persons with their TC/HDL-C >or= 4 and TG >or= 1.70 mmol/L was much larger among persons over forty than among persons under forty (20.74% vs. 10.99% among males and 13.32% vs. 2.05% among females).

CONCLUSION

The mean serum TC, TG, and LDL-C levels increased and the HDL-C level decreased significantly among healthy inhabitants in urban Shanghai in 1990 s. Along with the rise of living standards of people, their mean lipid level increases too. Nutrition education is necessary.

U7C beamline and XAFS station of national synchrotron radiation laboratory

The XAFS station on beamline U7C of National Synchrotron Radiation Laboratory (NSRL) was completely constructed in December 1998. The source for XAFS station is from a 3-pole superconducting wiggler with magnetic field of 6 T inserted in the straight section of the storage ring. Using a Si(111) double crystal monochromator with a fixed slit, the X-ray intensity at the sample position is about 3x10(9) photons/second at the energy of 8980 eV of Cu K-edge. The Keithley 65 17 electrometers are used to record the electron charges that are produced in the ionization chambers. A high ratio of signal to noise has been obtained for the XAFS spectra of Cu, Ni and Fe foils. Furthermore, the XAFS spectrum of Cu foil in NSRL is in good agreement with that obtained in BSRF and KEK.

Antisweet saponins from Gymnema sylvestre

Three new oleanane-type triterpene glycosides (1-3), along with the sodium salt of alternoside II (4), were isolated from an ethanol extract of the leaves of Gymnema sylvestre. The structures of these new saponins were identified as 21 beta-O-benzoylsitakisogenin 3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucuronopyranoside (1), the potassium salt of longispinogenin 3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucuronopyranoside (2), and the potassium salt of 29-hydroxylongispinogenin 3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucuronopyranoside (3). The aglycon of 3, gymnemagenol (3a), was characterized as 3 beta,16 beta,28, 29-tetrahydroxyolean-12-ene. Structure elucidation was accomplished by interpretation of NMR (DQF-COSY, HMQC, and HMBC) results, FABMS, and hydrolysis. Saponin 1 and the sodium salt of alternoside II (4) exhibited antisweet activity.

Inverse association between intake of cereal fiber and risk of gastric cardia cancer

BACKGROUND & AIMS

Recent data show that salivary nitrites form carcinogenic nitrosamines, especially at the gastric cardia. Wheat fiber has been shown to neutralize such mutagen formation. Our aim was to evaluate the association between dietary fiber and cancers of the esophageal and gastric cardia.

METHODS

We examined data from a large-scale population-based case-control study of risk factors for adenocarcinoma of the gastric cardia and esophagus and squamous cell carcinoma of the esophagus.

RESULTS

We found a strong dose-dependent inverse association between total dietary fiber intake and risk of gastric cardia adenocarcinoma, which was driven mainly by intake of cereal fiber. The odds ratio among individuals in the highest quartile of cereal fiber intake compared with the lowest was 0.3 (95% confidence interval, 0.2-0.5; P trend < 0.0001). High intake of cereal fiber was also associated with a moderately decreased risk of esophageal adenocarcinoma, but no linear dose-risk trend was observed. There was no association between dietary fiber and esophageal squamous cell carcinoma.

CONCLUSIONS

High intake of cereal fiber may significantly lower the risk of gastric cardia cancer.

Inverse association between intake of cereal fiber and risk of gastric cardia cancer

BACKGROUND & AIMS

Recent data show that salivary nitrites form carcinogenic nitrosamines, especially at the gastric cardia. Wheat fiber has been shown to neutralize such mutagen formation. Our aim was to evaluate the association between dietary fiber and cancers of the esophageal and gastric cardia.

METHODS

We examined data from a large-scale population-based case-control study of risk factors for adenocarcinoma of the gastric cardia and esophagus and squamous cell carcinoma of the esophagus.

RESULTS

We found a strong dose-dependent inverse association between total dietary fiber intake and risk of gastric cardia adenocarcinoma, which was driven mainly by intake of cereal fiber. The odds ratio among individuals in the highest quartile of cereal fiber intake compared with the lowest was 0.3 (95% confidence interval, 0.2-0.5; P trend < 0.0001). High intake of cereal fiber was also associated with a moderately decreased risk of esophageal adenocarcinoma, but no linear dose-risk trend was observed. There was no association between dietary fiber and esophageal squamous cell carcinoma.

CONCLUSIONS

High intake of cereal fiber may significantly lower the risk of gastric cardia cancer.

Reduction of inflammatory response in the mouse brain with adenoviral-mediated transforming growth factor-ss1 expression

Background and Purpose-Chemokines have been shown to play an important role in leukocyte and monocyte/macrophage infiltration into ischemic regions. The purpose of this study is to identify whether overexpression of the active human transforming growth factor-ss1 (ahTGF-ss1) can downregulate expression of monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha), and intercellular adhesion molecule-1 (ICAM-1) and reduce ischemic brain injury.

METHODS

-Overexpression of transforming growth factor-ss1 (TGF-ss1) was achieved through adenoviral gene transfer. Five days after adenoviral transduction, the mouse underwent 30 minutes of middle cerebral artery occlusion followed by 1 to 7 days of reperfusion. TGF-ss1, MCP-1, MIP-1alpha, and ICAM-1 were detected by enzyme-linked immunosorbent assay and immunohistochemistry. Infarct areas and volumes were measured by cresyl violet staining.

RESULTS

-MCP-1 and MIP-1alpha expression is increased after middle cerebral artery occlusion, and double-labeled immunostaining revealed that MCP-1 is colocalized with neurons and astrocytes. Viral-mediated TGF-ss1 overexpression was significantly greater at measured time points, with a peak at 7 to 9 days. The expression of MCP-1 and MIP-1alpha, but not ICAM-1, was reduced in the mice overexpressing ahTGF-ss1 (P:<0.05). Furthermore, infarct volume was significantly reduced in the mice overexpressing ahTGF-ss1 (P:<0.05).

CONCLUSIONS

-This study demonstrates that MCP-1 and MIP-1alpha expressed in the ischemic region may play an important role in attracting inflammatory cells. The reduction of MCP-1 and MIP-1alpha, but not ICAM-1, in the mice overexpressing ahTGF-ss1 suggests that the neuroprotective effect of TGF-ss1 may result from the inhibition of chemokines during cerebral ischemia and reperfusion.

Incidence of ovarian cancer among alcoholic women: a cohort study in Sweden

Linkage of nationwide databases in Sweden allowed us to evaluate the incidence of ovarian cancer among 36,856 women diagnosed with alcoholism between 1965 and 1994. Mean duration of follow-up was 9.6 years, for a total of 317,518 person-years at risk. The expected number of cases of ovarian cancer was calculated by multiplying the number of person-years by 5-year age group and calendar year-specific incidence rates of ovarian cancer in Sweden. The effect measure was the standardized incidence ratio (SIR), with 95% confidence intervals (CIs). Our results indicate an overall deficit of cases of ovarian cancer of about 14% among women with a diagnosis of alcoholism. This deficit is particularly strong and statistically significant among alcoholic women younger than 60 years (SIR = 0.76, 95% CI 0.58-1.00). This deficit is compatible with the reported reduction of gonadotrophin levels among alcoholic women younger than 60 years and with the hypothesis invoking these gonadotrophins in the etiology of ovarian cancer.

Identification and characterization of humic substances-degrading bacterial isolates from an estuarine environment

Bacterial isolates were obtained from enrichment cultures containing humic substances extracted from estuarine water using an XAD-8 resin. Eighteen isolates were chosen for phylogenetic and physiological characterization based on numerical importance in serial dilutions of the enrichment culture and unique colony morphology. Partial sequences of the 16S rRNA genes indicated that six of the isolates were associated with the alpha subclass of Proteobacteria, three with the gamma-Proteobacteria, and nine with the Gram-positive bacteria. Ten isolates degraded at least one (and up to six) selected aromatic single-ring compounds. Six isolates showed ability to degrade [(14)C]humic substances derived from the dominant salt marsh grass in the estuary from which they were isolated (Spartina alterniflora), mineralizing 0.4-1.1% of the humic substances over 4 weeks. A mixture of all 18 isolates did not degrade humic substances significantly faster than any of the individual strains, however, and no isolate degraded humic substances to the same extent as the natural marine bacterial community (3.0%). Similar studies with a radiolabeled synthetic lignin ([beta-(14)C]dehydropolymerisate) showed measurable levels of degradation by all 18 bacteria (3.0-8.8% in 4 weeks), but mineralization levels were again lower than that observed for the natural marine bacterial community (28.2%). Metabolic capabilities of the 18 isolates were highly variable and generally did not map to phylogenetic affiliation.

[Effect of amniotic membrane on expressions of TGF-beta 1, collagens I, III and fibronectin in rabbit corneal healing after photorefractive keratectomy]

OBJECTIVE

To observed the effect of amniotic membrane transplantation (AMT) on expressions of transforming growth factor-beta 1(TGF-beta 1), collagens I, III and fibronectin (FN) in rabbit corneal healing after photorefractive keratectomy (PRK), and investigate the anti-scarring formation mechanism of AMT.

METHODS

Ten rabbits underwent bilateral PRK to correct 8 diopters of myopia. One eye was randomly transplanted with preserved human amniotic membrane, and the other eye served as the control. The expressions of TGF-beta 1, collagens I, III and FN were studied by immunohistochemistry at 4 weeks after operation.

RESULTS

The expression of TGF-beta 1 in corneal epithelium and keratocytes and collegans in anterior stroma was significantly less in AMT group than in the control group. The expressions of collagens III and FN in anterior stroma of ablation area were also significantly less in AMT group than in the control group. The staining of collagen I had no significant difference between the AMT group and the control group.

CONCLUSION

The expressions of TGF-beta 1, collagens III and FN can be suppressed by amniotic membrane after PRK. These data suggest that part of the anti-scarring effect of AMT may be mediated through the suppression of TGF-beta 1, collagens III and FN expression.

No increased risk of breast cancer after cholecystectomy

An increased risk of breast cancer after cholecystectomy has been proposed, but the results in different studies have not been consistent. To explore this potential association, we conducted a large, population-based, record-linkage, cohort study in Sweden. The cohort consisted of 154,283 women who had been cholecystectomized during the period 1965-1994. The cohort was followed up for breast cancer by the Swedish Cancer Register. The standardized incidence ratio (SIR), the ratio of the observed to the expected number of incident cancers derived from the entire Swedish population, estimated relative risk. During a follow-up of 31 years, we observed 3,879 cases of breast cancer in the cohort vs. 3,843 expected [SIR = 1.01, 95% confidence interval (CI) 0.98-1.04]. No significant difference in risk was observed across duration of follow-up or age at follow-up. Among women followed up for more than 20 years after cholecystectomy, the observed 403 cases of breast cancer rendered an SIR of 0.96 (95% CI 0.87-1.06). The results remained virtually unchanged after controlling for possible confounding effects of obesity and diabetes. Also, we did not find any evidence of an association between gall stone disease per se and the risk of breast cancer. We conclude that cholecystectomy and breast cancer are not likely to be associated.

Alcohol and breast cancer risk: the alcoholism paradox

A population-based cohort study of 36 856 women diagnosed with alcoholism in Sweden between 1965 and 1995 found that alcoholic women had only a small 15% increase in breast-cancer incidence compared to the general female population. It is therefore apparent, contrary to expectation, that alcoholism does not increase breast-cancer risk in proportion to presumed ethanol intake.

Factors affecting sentinel node localization during preoperative breast lymphoscintigraphy

Variable success rates for identifying axillary (AX) sentinel nodes in breast cancer patients using preoperative lymphoscintigraphy have been reported. We evaluated the effects of age, weight, breast size, method of biopsy, interval after biopsy, and imaging view on the success of sentinel node identification and on the kinetics of radiopharmaceutical migration.

METHODS

Preoperative breast lymphoscintigraphy was performed in consecutive breast cancer patients from February 1998 to December 1998. The ipsilateral shoulder was elevated on a foam wedge and the arm was abducted and elevated overhead. Imaging using this modified oblique view of the axilla (MOVA) started immediately after peritumoral injection of Millipore-filtered 99mTc-sulfur colloid and continued until AX sentinel nodes were identified. Anterior views were obtained after MOVA. AX, internal mammary (IM), and clavicular (CL) basins were monitored in all patients. MOVA was compared with the anterior view for sentinel node identification. Age, weight, breast size, method of biopsy, interval after biopsy, and primary tumor location were evaluated for their effects on sentinel node localization and transit times from injection to arrival at the sentinel nodes.

RESULTS

Seventy-six lymphoscintigrams were obtained for 75 patients. AX sentinel nodes were revealed in 75 (99%) cases. IM or CL sentinel nodes were found in 19 (25%) cases and were not related to tumor location; exclusive IM drainage was present in 1 (1%) case. Identification of AX sentinel nodes was equivalent with MOVA and anterior views in 18 (24%) patients, was better with MOVA in 20 (26%) patients, and was accomplished only with MOVA in 38 (50%) patients. Median transit time was 17.5 min (range, 1 min to 18 h) after injection, and larger breast size was associated with increased transit time. No effect of age, weight, biopsy method, interval from biopsy, or tumor location on transit time was found.

CONCLUSION

Use of MOVA can improve identification of AX sentinel nodes. Although AX drainage is the predominant pattern, a tumor in any portion of the breast can drain to IM sentinel nodes. Transit time was influenced by breast size. Overall short arrival times with this technique allow sentinel lymph node dissection to be performed on the same day as lymphoscintigraphy.

Activation of mitogen-activated protein kinases after permanent cerebral artery occlusion in mouse brain

The purpose of this study was to examine the activation, topographic distribution, and cellular location of three mitogen-activated protein kinases (MAPKs) after permanent middle cerebral artery occlusion (MCAO) in mice. Phosphorylated MAPKs expression in the ischemic region was quantified using Western blot analysis and localized immunohistochemically using the diaminobenzide staining and double-labeled immunostaining. Extracellular signal-regulated kinases 1 and 2 (ERK1 and ERK2), p38 mitogen-activated protein (p38), and c-Jun NH2-terminal kinase or stress-activated protein kinase (SAPK/JNK) were initially activated at 30 minutes, 10 minutes, and 5 minutes, respectively, after focal cerebral ischemia. Peak expression represented a 2.7-fold, 3.7-fold, and 4.8-fold increase in each of these MAPKs, respectively. The immunohistochemical expressions of ERK1, ERK2, p38, and SAPK/JNK protein paralleled the Western blot analysis results. Double-labeled immunofluorescent staining demonstrated that the neurons and astrocytes expressed ERK1, ERK2, p38, and SAPK/JNK during the early time points after MCAO. The current results demonstrate that brain damage after ischemia rapidly triggers time-dependent ERK1, ERK2, p38, and SAPK/ JNK phosphorylation, and reveals that neurons and astrocytes are involved in the activation of the MAPK pathway. This very early expression of MAPKs suggests that MAPKs may be closely involved in signal transduction during cerebral ischemia.

The changes of TGF-alpha, TGF-beta 1 and basic FGF messenger RNA expression in rabbit cornea after photorefractive keratectomy

OBJECTIVE

To study the mechanism of haze formation and investigate the expression changes of transforming growth factor-alpha (TGF-alpha), transforming growth factor-beta 1(TGF-beta 1) and basic fibroblast growth factor (bFGF) mRNA in corneal epithelium and stroma after photorefractive keratectomy (PRK).

METHODS

Sixteen white rabbits were randomly divided into 4 groups, and PRK was performed on each eye of 12 rabbits. The haze formation was examined under a slit-lamp microscope at the 1st, 2nd and 3rd month after PRK, and the expressions of TGF-alpha, TGF-beta 1 and bFGF mRNA were detected with in situ hybridization.

RESULTS

The corneal haze formed at the 1st month after PRK. The most prominent haze formation was observed at the 2nd month, and declined gradually at the 3rd month after ablation. TGF-alpha mRNA expression was presented on the normal corneal epithelium and not on the corneal stroma. TGF-beta 1 and bGFG mRNA were expressed by both corneal epithelium and stroma. The capacities for cornea tissue expression of three growth factors mRNA increased after PRK, and the peaks appeared on the 1st, 2nd month. The extent for expressions of three growth factors related proportionally to the haze formation.

CONCLUSION

Three growth factors took part in promoting corneal wound healing after PRK, and might contribute to corneal haze formation and development.

Antioxidants and cancers of the esophagus and gastric cardia

Antioxidant vitamins have attracted considerable attention in previous studies of esophageal squamous-cell carcinoma, but dietary studies of adenocarcinoma of the esophagus and gastric cardia remain sparse. Treating these tumors as distinct diseases, we studied intakes of vitamin C, beta-carotene and alpha-tocopherol in a nationwide population-based case-control study in Sweden, with 185, 165, and 258 cases of esophageal adenocarcinoma, esophageal squamous-cell carcinoma, and gastric cardia adenocarcinoma, respectively, and 815 controls. Subjects with a high parallel intake of vitamin C, beta-carotene, and alpha-tocopherol showed a 40-50% decreased risk of both histological types of esophageal cancer compared with subjects with a low parallel intake. Antioxidant intake was not associated with the risk of gastric cardia adenocarcinoma. Separately, vitamin C and beta-carotene reduced the risk of esophageal cancers more than alpha-tocopherol. We found that antioxidant intake is associated with similar risk reductions for both main histological types of esophageal cancer. Our findings indicate that antioxidants do not explain the diverging incidence rates of the 2 histological types of esophageal cancer. Moreover, our data suggest that inverse associations with esophageal squamous-cell carcinoma and adenocarcinoma may be stronger among subjects under presumed higher oxidative stress due to smoking or gastroesophageal reflux, respectively. Our results may be relevant for the implementation of focused, cost-effective preventive measures.

[Analysis on genetic pattern of familial type II diabetes mellitus]

OBJECTIVE

To analyse hereditary familial type II diabetes mellitus (type II DM), including its pattern and the transmitted expression on different sex of type II DM.

METHODS

Familial analysis, segregation analysis, tests were used for multifactorial inheritance and threshold analysis. One hundred seventy-seven pedigrees of familial type II DM were studied.

RESULTS

The heritability of familial type II DM was 143.06% +/- 3.3%. One dominant major gene might influence the genesis of type II DM. There were 214 nuclear families in 3 different mating types: U x U, U x A and A x A. The segregation ratios of U x U, U x A and A x A were 0.4703, 0.4838 and 0.6712 respectively. The results of tests for multifactorial inheritance and segregation analysis indicated that the genetic pattern of U x A and A x A nuclear families was not multifactorial inheritant and autosomal recessive (AR) but autosomal dominant (AD) inheritance. The genetic pattern of U x U nuclear families was neither AD nor AR inheritance.

CONCLUSION

There was genetic heterogeneity in type II DM discovered with subgroupes of autosomal dominant inheritance in type II DM.

Dietary antioxidant intake and the risk of cardia cancer and noncardia cancer of the intestinal and diffuse types: a population-based case-control study in Sweden

In spite of diverging incidence trends, subsite, and subtype-specific gastric cancer data on the association with dietary antioxidants are sparse. We aimed to test whether the apparent protective effect of antioxidants is mainly confined to noncardia (distal) cancer of the intestinal subtype, to which most of the incidence decline in gastric cancer has been ascribed. In a Swedish study base (total population 1.3 million), we interviewed 567 cases uniformly classified to subsite (cardia vs. noncardia) and subtype (intestinal vs. diffuse), and 1165 population-based controls, frequency matched for age and sex. Serologic data on H. pylori status was available for a subset of 542 individuals. Ascorbic acid (vitamin C) was inversely associated with all subsites and subtypes of gastric cancer in a significant dose-response manner (all p<0.05), with risk reductions between 40% and 60%. beta-carotene was also strongly and negatively associated with risk, particularly with the intestinal type. The associations with alpha-tocopherol (vitamin E) were less clear. The highest parallel intake of all three antioxidants (quartiles 4), compared to those with the lowest parallel intakes (quartiles 1), was associated with a 70% lower risk of developing noncardia cancer (OR 0.3, 95% CI 0.1-0.9). Our results suggest that antioxidants might be especially beneficial among subjects at increased risk for gastric cancer such as smokers and those infected by H. pylori. We conclude that a high intake of antioxidants, as a consequence of high consumption of fruit and vegetables, may lower the risk not only for gastric cancer of the intestinal type, but also for diffuse type adenocarcinoma and cardia cancer.

Dietary antioxidant intake and the risk of cardia cancer and noncardia cancer of the intestinal and diffuse types: a population-based case-control study in Sweden

In spite of diverging incidence trends, subsite, and subtype-specific gastric cancer data on the association with dietary antioxidants are sparse. We aimed to test whether the apparent protective effect of antioxidants is mainly confined to noncardia (distal) cancer of the intestinal subtype, to which most of the incidence decline in gastric cancer has been ascribed. In a Swedish study base (total population 1.3 million), we interviewed 567 cases uniformly classified to subsite (cardia vs. noncardia) and subtype (intestinal vs. diffuse), and 1165 population-based controls, frequency matched for age and sex. Serologic data on H. pylori status was available for a subset of 542 individuals. Ascorbic acid (vitamin C) was inversely associated with all subsites and subtypes of gastric cancer in a significant dose-response manner (all p<0.05), with risk reductions between 40% and 60%. beta-carotene was also strongly and negatively associated with risk, particularly with the intestinal type. The associations with alpha-tocopherol (vitamin E) were less clear. The highest parallel intake of all three antioxidants (quartiles 4), compared to those with the lowest parallel intakes (quartiles 1), was associated with a 70% lower risk of developing noncardia cancer (OR 0.3, 95% CI 0.1-0.9). Our results suggest that antioxidants might be especially beneficial among subjects at increased risk for gastric cancer such as smokers and those infected by H. pylori. We conclude that a high intake of antioxidants, as a consequence of high consumption of fruit and vegetables, may lower the risk not only for gastric cancer of the intestinal type, but also for diffuse type adenocarcinoma and cardia cancer.

Dietary antioxidant intake and the risk of cardia cancer and noncardia cancer of the intestinal and diffuse types: a population-based case-control study in Sweden

In spite of diverging incidence trends, subsite, and subtype-specific gastric cancer data on the association with dietary antioxidants are sparse. We aimed to test whether the apparent protective effect of antioxidants is mainly confined to noncardia (distal) cancer of the intestinal subtype, to which most of the incidence decline in gastric cancer has been ascribed. In a Swedish study base (total population 1.3 million), we interviewed 567 cases uniformly classified to subsite (cardia vs. noncardia) and subtype (intestinal vs. diffuse), and 1165 population-based controls, frequency matched for age and sex. Serologic data on H. pylori status was available for a subset of 542 individuals. Ascorbic acid (vitamin C) was inversely associated with all subsites and subtypes of gastric cancer in a significant dose-response manner (all p<0.05), with risk reductions between 40% and 60%. beta-carotene was also strongly and negatively associated with risk, particularly with the intestinal type. The associations with alpha-tocopherol (vitamin E) were less clear. The highest parallel intake of all three antioxidants (quartiles 4), compared to those with the lowest parallel intakes (quartiles 1), was associated with a 70% lower risk of developing noncardia cancer (OR 0.3, 95% CI 0.1-0.9). Our results suggest that antioxidants might be especially beneficial among subjects at increased risk for gastric cancer such as smokers and those infected by H. pylori. We conclude that a high intake of antioxidants, as a consequence of high consumption of fruit and vegetables, may lower the risk not only for gastric cancer of the intestinal type, but also for diffuse type adenocarcinoma and cardia cancer.

Heredity and risk of cancer of the esophagus and gastric cardia

The importance of genetic factors in the etiology of esophageal cancer is uncertain. We addressed the question of heredity in a population-based, nationwide case-control study conducted in Sweden during 1995 through 1997. The study involved 189 patients with esophageal adenocarcinoma, 262 with cardia adenocarcinoma, 167 with esophageal squamous cell carcinoma, and, for comparison, 820 control subjects. Familial occurrence of cancer was explored at face-to-face interviews. Logistic regression, with multivariate adjustment for potential confounders, was used to calculate odds ratios (ORs), which estimated relative risk. Occurrence of esophageal cancer among first-degree relatives did not increase the risk of adenocarcinoma or squamous cell carcinoma of the esophagus. Neither were there any significant associations with familial occurrence of gastric cancer or other gastrointestinal tumors. The risk of cardia adenocarcinoma was moderately increased among persons with first-degree relatives with gastric cancer (OR, 1.6; 95% confidence interval, 1.0-2.6). Familial occurrence of any cancer was not associated with increased risks of any of the three studied tumors. In conclusion, heredity does not seem to contribute importantly to the occurrence of esophageal cancer of any histological type. A weak association between familial gastric cancer and the risk of cardia cancer may represent a genetic link.

Prospective observational study of sentinel lymphadenectomy without further axillary dissection in patients with sentinel node-negative breast cancer

PURPOSE

Immediate complete axillary lymphadenectomy (ALND) after sentinel lymphadenectomy (SLND) has confirmed that tumor-negative sentinel nodes accurately predict tumor-free axillary nodes in breast cancer. Therefore, we hypothesized that SLND alone in patients with tumor-negative sentinel nodes would achieve axillary control, with minimal complications.

PATIENTS AND METHODS

Between October 1995 and July 1997, 133 consecutive women who had primary invasive breast tumors clinically </= 4 cm in diameter and no axillary lymphadenopathy were prospectively entered onto a trial of SLND using vital blue dye. Sentinel nodes were examined by standard microscopy or immunohistochemistry. SLND was the only axillary surgery if sentinel nodes were tumor-free. Completion ALND was performed only if sentinel nodes contained metastases or if they were not identified. Excluded from subsequent analysis were patients with unsuspected multifocal carcinoma and those who refused completion ALND. The complication and axillary recurrence rates after SLND without ALND were determined.

RESULTS

Sentinel nodes were identified in 132 (99%) of 133 patients. Eight patients were excluded from further analysis. Of the 125 assessable patients, 57 had tumor-positive sentinel nodes and one had an unsuccessful mapping procedure; these patients underwent completion ALND. In the remaining 67 patients (54%), SLND was the only axillary procedure. Complications occurred in 20 patients (35%) undergoing ALND after SLND but in only two patients (3%) undergoing SLND alone (P =.001). There were no local or axillary recurrences at a median follow-up of 39 months.

CONCLUSION

Complication rates are negligible after SLND alone. An absence of axillary recurrences supports SLND as an accurate staging alternative for breast cancer and suggests that routine ALND can be eliminated for patients with histopathologically negative sentinel nodes.

Residential randon exposure and lung cancer risk in Misasa, Japan: a case-control study

In order to investigate an association between residential radon exposure and risk of lung cancer, a case-control study was conducted in Misasa Town, Tottori Prefecture, Japan. The case series consisted of 28 people who had died of lung cancer in the years 1976-96 and 36 controls chosen randomly from the residents in 1976, matched by sex and year of birth. Individual residential radon concentrations were measured for 1 year with alpha track detectors. The average radon concentration was 46 Bq/m3 for cases and 51 Bq/m3 for controls. Compared to the level of 24 or less Bq/m3, the adjusted odds ratios of lung cancer associated with radon levels of 25-49, 50-99 and 100 or more Bq/m3, were 1.13 (95% confidence interval; 0.29-4.40), 1.23 (0.16-9.39) and 0.25 (0.03-2.33), respectively. None of the estimates showed statistical significance, due to small sample size. When the subjects were limited to only include residents of more than 30 years, the estimates did not change substantially. This study did not find that the risk pattern of lung cancer, possibly associated with residential radon exposure, in Misasa Town differed from patterns observed in other countries.

[Combined use of steroid hormone and low dose gossypol for antifertility and its mechanism in rats]

OBJECTIVE

To study the feasibility and the morphological mechanism of combined use of steroid hormone (methyltestosterone and ethinyl estradiol) and low dose gossypol for antifertility in adult Wistar rats.

METHODS

We used methyltestosterone 20 mg/(kg.d), ethinyl estradiol 100 micrograms/(kg.d), and gossypol 12 mg/(kg.d) to feed male rats for 6 weeks via gastric intubation to induce infertility, then used gossypol 12 mg/(kg.d) alone for another 12 weeks to maintain infertility. Testicular sperm counts, cauda epididymal sperm motility, and sperm silver staining were used to determine infertility and morphology of sperm at the end of the two phases. Testicular morphology of the rats was observed from HE and PAS staining of paraffin sections. F1 generation of the rats would be examined in a series of behavioral tests after their 6-week recovery periods.

RESULTS

There was no substantial change in testicular sperm counts of drugs-treated rats both for 6 weeks and 6 plus 12 weeks compared with that of control. But cauda epididymal sperm motility of drugs-treated rats went down to zero at the end of two phrases. The result of sperm silver staining showed that epididymal sperm were all deleterious of either segregation of sperm nucha from sperm head, or separation in annular granule of sperm tail. The observation of testicular morphology suggested that spermatogenesis is only partially affected. The ratios of stages II-III (9.3 +/- 3.4)% and stages IX-X (3.6 +/- 0.6)% were remarkably dropped, but that of stages IV-VI (36.7 +/- 5.0)% obviously ascended comparing with (26.8 +/- 1.7)%, (6.0 +/- 0.4)%, (24.5 +/- 2.7)% of control at the end of 6 plus 12 weeks. Moreover, no adverse effect was found in viscera tissue sections.

CONCLUSIONS

Steroid hormone made the procedure of spermatogenesis slower and low dose gossypol caused all sperm lose their activity in epididymis. Both affect the process of spermatogenesis from different endpoints and successfully induce infertility in short term. Low dose gossypol not only executes its antifertility function in epididymis, but also affects the quality of spermatozoal production in testis by impacting the procedures of both acrosomal formation and spermatozoal elongation, so it can completely maintain infertility in long term. The infertility was reversible that the infertile rats can be recovery in about 6 weeks. Their F1 generation were proved to be normal through a set of behavioral tests.

[Male contraception of triptonide and its function mechanism]

OBJECTIVE

The male contraceptive mechanism in rats of triptonide, isolated from Multiglycosides of Tripterygium wilfordii (GTW), was investigated.

METHODS

The dosage of triptonide was 200 micrograms/(kg.d), fed for 8 weeks via gastric intubation. Sperm counts, sperm motility, and sperm silver staining were used to test the antispermatogenic effect of triptonide; the study of morphology was learned from paraffin sections of testis and visceras of triptonide-treated rats; protamine was abstracted from testis by electrophoresis; using antisense mRNA of cyclin D1 and Cdk4 as prodes, we examined the expression of cyclin D1 and Cdk4 through hybridization in situ.

RESULTS

Sperm counts (26.43 +/- 3.90) x 10(6)/g and sperm motility(66.0 +/- 6.8)% of triptonide-treated rats were substantially different from those of control, (41.15 +/- 5.51) x 10(6)/g (P < 0.01) and (88.0 +/- 2.0)% (P < 0.001). Paraffin sections of testis of triptonide-treated rats stained by PAS showed that the number of spermatids per 100 sertoli cells (9.15 +/- 0.33) was remarkably decreased compared with control's (10.73 +/- 0.38) (P < 0.001). At the same time, delaying sperm-released process was observed, which affects the nature course of sperm. And the extended vacuoles of vary sizes, the segregation of cells in lumens were also found in the cross-section of testis of rats treated with triptonide. In addition, the contents of protamine (4.6 +/- 2.2)% was extremely decreased, compared with the control's (40.6 +/- 7.2)% (P < 0.001). By using antisense mRNA of cyclin D1 and Cdk4 as prodes, we detected that the expression of the genes was notably increased in spermatids.

CONCLUSIONS

The results suggest the antispermatogenic effect of triptonide is very well and it mainly plays its role on spermatids by increasing the expression of cyclin D1 and Cdk4, meanwhile, decreasing the biosynthesis of protamine. The appropriate target region of triptonide makes itself most potency to be a suitable male antifertility drug.