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.

Energy-driven integrated hardware-software optimizations using SimplePower

With the emergence of a plethora of embedded and portable applications, energy dissipation has joined throughput, area, and accuracy/precision as a major design constraint. Thus, designers must be concerned with both optimizing and estimating the energy consumption of circuits, architectures, and software. Most of the research in energy optimization and/or estimation has focused on single components of the system and has not looked across the interacting spectrum of the hardware and software. The novelty of our new energy estimation framework, SimplePower , is that it evaluates the energy considering the system as a whole rather than just as a sum of parts, and that it concurrently supports both compiler and architectural experimentation.

We present the design and use of the SimplePower framework that includes a transition-sensitive, cycle-accurate datapath energy model that interfaces with analytical and transition sensitive energy models for the memory and bus subsystems, respectively. We analyzed the energy consumption of ten codes from the multidimensional array domain, a domain that is important for embedded video and signal processing systems, after applying different compiler and architectural optimizations. Our experiments demonstrate that early estimates from the SimplePower energy estimation framework can help identify the system energy hotspots and enable architects and compiler designers to focus their efforts on these areas.

Synthesis and preliminary biological evaluations of CC-1065 analogues: effects of different linkers and terminal amides on biological activity

CC-1065 analogues possessing a biologically active CBI functional group and amide-substituted indole and benzofuran were synthesized. The IC(50) values of compounds 26, bearing two indoles, and 25, bearing only one indole, are 0.4 and 3 nM, respectively, against U937 leukemia cells in vitro. The IC(50) values of compounds 28, bearing a butyramino group, and 27, bearing an acetamino group, are 0.008 and 0.4 nM, respectively, against U937 leukemia cells in vitro. Compound 29, bearing a double-bond linker, is about 4-fold more potent than 25, bearing no double-bond linker. Compound 26 is highly potent against all cell lines tested in the NCI in vitro screening with IC(50) values in the 0.1-5 nM range for most cell lines. Compounds 26 and 30 are highly active against L1210 leukemia in mice. Compound 26 is also active against B16BL6 melanoma in mice. Most importantly, 26 and 30 are not myelosuppressive at therapeutically effective doses. The mechanism of tumor cell death is through induction of apoptosis, and is accompanied by DNA fragmentation.

Stimulation of adenosine A3 receptors in cerebral ischemia. Neuronal death, recovery, or both?

The role of the adenosine A3 receptor continues to baffle, and, despite an increasing number of studies, the currently available data add to, rather than alleviate, the existing confusion. The reported effects of adenosine A3 receptor stimulation appear to depend on the pattern of drug administration (acute vs. chronic), dose, and type of the target tissue. Thus, while acute exposure to A3 receptor agonists protects against myocardial ischemia, it is severely damaging when these agents are given shortly prior to cerebral ischemia. Mast cells degranulate when their A3 receptors are stimulated. Degranulation of neutrophils is, on the other hand, impaired. While reduced production of reactive nitrogen species has been reported following activation of A3 receptors in collagen-induced arthritis, the process appears to be enhanced in cerebral ischemia. Indeed, immunocytochemical studies indicate that both pre- and postischemic treatment with A3 receptor antagonist dramatically reduces nitric oxide synthase in the affected hippocampus. Even more surprisingly, low doses of A3 receptor agonists seem to enhance astrocyte proliferation, while high doses induce their apoptosis. This review concentrates on the studies of cerebral A3 receptors and, based on the available evidence, discusses the possibility of adenosine A3 receptor serving as an integral element of the endogenous cerebral neuroprotective complex consisting of adenosine and its receptors.

Cernuosides A and B, two sucrase inhibitors from Pulsatilla cernua

Two oleanane-type oligoglycosides, cernuosides A (1) and B (2), were isolated from the roots of Pulsatilla cernua (Ranunculaceae). Structure elucidation was accomplished by 1D and 2D NMR (DQF-COSY, TOCSY, HMQC, HMBC, and ROESY) methods, FABMS, and hydrolysis. Both compounds showed moderate activity against sucrase.

The seven-transmembrane receptor smoothened cell-autonomously induces multiple ventral cell types

Sonic Hedgehog (Shh) is a secreted protein that controls cell fate and mitogenesis in the developing nervous system. Here we show that a constitutively active form of Smoothened (Smo-M2) mimics concentration-dependent actions of Shh in the developing neural tube, including activation of ventral marker genes (HNF3beta, patched, Nkx2.2, netrin-1), suppression of dorsal markers (Pax-3, Gli-3, Ephrin A5) and induction of ventral neurons (dopaminergic, serotonergic) and ventrolateral motor neurons (Islet-1+, Islet-2+, HB9+) and interneurons (Engrailed-1+, CHX10+). Furthermore, Smo-M2's patterning activities were cell autonomous, occurring exclusively in cells expressing Smo-M2. These findings suggest that Smo is a key signaling component in the Hh receptor and that Shh patterns the vertebrate nervous system as a morphogen, rather than through secondary relay signals.

New cycloartane glycosides from Cimicifuga dahurica

Two new cylcoartane glycosides along with a known compound, 12beta-hydroxycimigenol 3- O-alpha- L-arabinopyranoside, were isolated from the rhizomes of Cimicifuga dahurica (Ranunculaceae). The structures of the new compounds were elucidated as cimigenol 3- O-alpha- L-arabinopyranoside and 25- O-acetylcimigenol 3- O-alpha- L-arabinopyranoside on the basis of chemical and spectral evidence.

Characterization of the human suppressor of fused, a negative regulator of the zinc-finger transcription factor Gli

Drosophila Suppressor of fused (Su(fu)) encodes a novel 468-amino-acid cytoplasmic protein which, by genetic analysis, functions as a negative regulator of the Hedgehog segment polarity pathway. Here we describe the primary structure, tissue distribution, biochemical and functional analyses of a human Su(fu) (hSu(fu)). Two alternatively spliced isoforms of hSu(fu) were identified, predicting proteins of 433 and 484 amino acids, with a calculated molecular mass of 48 and 54 kDa, respectively. The two proteins differ only by the inclusion or exclusion of a 52-amino-acid extension at the carboxy terminus. Both isoforms were expressed in multiple embryonic and adult tissues, and exhibited a developmental profile consistent with a role in Hedgehog signaling. The hSu(fu) contains a high-scoring PEST-domain, and exhibits an overall 37% sequence identity (63% similarity) with the Drosophila protein and 97% sequence identity with the mouse Su(fu). The hSu(fu) locus mapped to chromosome 10q24-q25, a region which is deleted in glioblastomas, prostate cancer, malignant melanoma and endometrial cancer. HSu(fu) was found to repress activity of the zinc-finger transcription factor Gli, which mediates Hedgehog signaling in vertebrates, and to physically interact with Gli, Gli2 and Gli3 as well as with Slimb, an F-box containing protein which, in the fly, suppresses the Hedgehog response, in part by stimulating the degradation of the fly Gli homologue. Coexpression of Slimb with Su(fu) potentiated the Su(fu)-mediated repression of Gli. Taken together, our data provide biochemical and functional evidence for the hypothesis that Su(fu) is a key negative regulator in the vertebrate Hedgehog signaling pathway. The data further suggest that Su(fu) can act by binding to Gli and inhibiting Gli-mediated transactivation as well as by serving as an adaptor protein, which links Gli to the Slimb-dependent proteasomal degradation pathway.

Tobacco, alcohol and the risk of gastric cancer by sub-site and histologic type

Few studies have provided information on the role of smoking and alcohol in the carcinogenesis of gastric cancer by sub-site and histologic type. The relationship of snuff dipping with risk of gastric cancer has also been rarely studied. In a population-based case-control study conducted in 5 counties of Sweden from February 1989 to January 1995, a total of 90 cases of gastric cardia cancer, 260 and 164 cases of distal gastric cancer of intestinal and diffuse types, respectively, and 1164 frequency-matched control subjects were personally interviewed about life-time smoking, use of smokeless tobacco and use of alcohol 20 years ago. Current smokers had a higher risk than never-smokers for all 3 kinds of gastric adenocarcinoma [odds ratio (OR) 1.7, 95% confidence interval (CI) 1.0-3.1 for gastric cardia adenocarcinoma; OR 1.8, 95% CI 1.2-2.7 for distal gastric cancer of intestinal type; and OR 2.2, 95% CI 1.4-3.5 for distal gastric cancer of diffuse type], and the risk rose with increasing dose and duration of smoking among current smokers. However, no elevated risk was observed for ex-smokers. Neither intake of alcoholic beverages nor snuff dipping was associated with an increased risk of any type of cardia or gastric cancer. Our study did not support the hypothesis that the role of tobacco differs by sub-site and histologic sub-type of gastric cancer.

Tobacco, alcohol and the risk of gastric cancer by sub-site and histologic type

Few studies have provided information on the role of smoking and alcohol in the carcinogenesis of gastric cancer by sub-site and histologic type. The relationship of snuff dipping with risk of gastric cancer has also been rarely studied. In a population-based case-control study conducted in 5 counties of Sweden from February 1989 to January 1995, a total of 90 cases of gastric cardia cancer, 260 and 164 cases of distal gastric cancer of intestinal and diffuse types, respectively, and 1164 frequency-matched control subjects were personally interviewed about life-time smoking, use of smokeless tobacco and use of alcohol 20 years ago. Current smokers had a higher risk than never-smokers for all 3 kinds of gastric adenocarcinoma [odds ratio (OR) 1.7, 95% confidence interval (CI) 1.0-3.1 for gastric cardia adenocarcinoma; OR 1.8, 95% CI 1.2-2.7 for distal gastric cancer of intestinal type; and OR 2.2, 95% CI 1.4-3.5 for distal gastric cancer of diffuse type], and the risk rose with increasing dose and duration of smoking among current smokers. However, no elevated risk was observed for ex-smokers. Neither intake of alcoholic beverages nor snuff dipping was associated with an increased risk of any type of cardia or gastric cancer. Our study did not support the hypothesis that the role of tobacco differs by sub-site and histologic sub-type of gastric cancer.

Attenuation of temporary focal cerebral ischemic injury in the mouse following transfection with interleukin-1 receptor antagonist

The proinflammatory cytokine interleukin-1 beta (IL-1beta) is thought to play an important role in the stimulation of the inflammatory response following ischemia and reperfusion. This study investigated the inflammatory effect of IL-1beta during transient focal cerebral ischemia and reperfusion in the mouse transduced with the interleukin-1 receptor antagonist (IL-1ra) gene. An adenoviral vector encoding, either the human IL-1ra gene (AdRSVIL-1ra) or the LacZ gene (AdRSVlacZ) or normal saline, were injected into the right lateral ventricles of adult CD-1 mice (n=96). Five days later, the mice received 1 h temporary middle cerebral artery occlusion (tMACAO) followed by 23 h reperfusion. Cerebral blood flow (CBF), infarct volume, blood-brain barrier (BBB) permeability, and the number of intracellular adhesion molecule-1 positive vessels were measured to determine the effect of IL-1beta during postischemic reperfusion. Infarct volume in the AdRSVIL-1ra-transduced mice was markedly reduced compared to the AdRSVlacZ-transduced and saline-injected mice (36.0+/-5.3 mm(3) vs. 60.0+/-6.2 mm(3), 69. 5+/-6.3 mm(3), after 23 h of reperfusion, n=6-8 per group, p<0.05). BBB disruption and intracellular adhesion molecule-1 expression (135+/-23 vs. 311+/-40 and 357+/-51, n=6-8 per group, p<0.05) in the AdRSVIL-1ra-transduced mice were also less than that of the AdRSVlacZ-transduced and saline-injected mice. Our studies demonstrated that overexpression of IL-1ra in the mouse brain can downregulate intracellular adhesion molecule-1 expression both in the cortex and basal ganglia, which suggests that IL-1beta may play an important role in the activation of the inflammatory response during focal cerebral ischemia by promoting leukocyte adhesion to endothelial cells. The decrease of BBB disruption in AdRSVIL-1ra-transduced mice suggests that the endothelial cells may be a target for IL-1beta during postischemic reperfusion.

[Effect of alum on intestinal microecological balance in mice]

OBJECTIVE

To observe the degree of microecological imbalance induced by alum in normal intestine of mice, and the bacterial adherence activity in the intestine of the mice administered orally with alum.

METHODS

The mice were medicated orally with alum of small and large doses (0.25 g/kg and 1 g/kg) for 8 weeks, then 5 weeks after stopping administration of alum, microflora analysis and bacterial adherence to intestinal mucosal epithelial cells were carried out respectively.

RESULTS

Eight weeks after administration with alum, the counts of Bifidobacteria and Lactobacilli decreased significantly, but the numbers of pathogenetic E. Coli increased significantly. The adherence rate of Bifidobacteria to the enterocytes of mice reduced markedly, but E. Coli was on the contrary of Bifidobacteria. Five weeks after the ceasing of medication, the intestinal flora were balanced, the adherence rate of both strains as mentioned above recovered to normal level.

CONCLUSION

The imbalance of intestinal flora of mice administered with alum for a long time were only the transient change of bacterial counts. The imbalance of intestinal flora and the adherence rate of bacteria regained normal status five weeks after cancelling action factor.

Thermodynamic contribution of nucleoside modifications to yeast tRNA(Phe) anticodon stem loop analogs

The determination of the structural and functional contributions of natural modified nucleosides to tRNA has been limited by lack of an approach that can systematically incorporate the modified units. We have produced a number of oligonucleotide analogs, of the anticodon of yeast tRNA(Phe) by, combining standard automated synthesis for the major nucleosides with specialty chemistries for the modified nucleosides. In this study, both naturally occurring and unnatural modified nucleotides were placed in native contexts. Each oligonucleotide was purified and the nucleoside composition determined to validate the chemistry. The RNAs were denatured and analyzed to determine the van't Hoff thermodynamic parameters. Here, we report the individual thermodynamic contributions for Cm, Gm, m1G, m5C, psi. In addition m5m6U, m1psi, and m3psi, were introduced to gain additional understanding of the physicochemical contribution of psi and m5C at an atomic level. These oligonucleotides demonstrate that modifications have measurable thermodynamic contributions and that loop modifications have global contributions.

A YAC-based physical map of the mouse genome

A physical map of the mouse genome is an essential tool for both positional cloning and genomic sequencing in this key model system for biomedical research. Indeed, the construction of a mouse physical map with markers spaced at an average interval of 300 kb is one of the stated goals of the Human Genome Project. Here we report the results of a project at the Whitehead Institute/MIT Center for Genome Research to construct such a physical map of the mouse. We built the map by screening sequenced-tagged sites (STSs) against a large-insert yeast artificial chromosome (YAC) library and then integrating the STS-content information with a dense genetic map. The integrated map shows the location of 9,787 loci, providing landmarks with an average spacing of approximately 300 kb and affording YAC coverage of approximately 92% of the mouse genome. We also report the results of a project at the MRC UK Mouse Genome Centre targeted at chromosome X. The project produced a YAC-based map containing 619 loci (with 121 loci in common with the Whitehead map and 498 additional loci), providing especially dense coverage of this sex chromosome. The YAC-based physical map directly facilitates positional cloning of mouse mutations by providing ready access to most of the genome. More generally, use of this map in addition to a newly constructed radiation hybrid (RH) map provides a comprehensive framework for mouse genomic studies.

[Clinical study on effect of Chinese herbal medicine for supplementing kidney and qi and activating blood circulation in treating intrauterine growth retardation of fetus]

OBJECTIVE

To explore the therapeutic effect and its possible mechanism on using Chinese herbal medicine (CHM) for supplementing Kidney and Qi, and activating blood circulation in treating intrauterine growth retardation of fetus (IUGR).

METHODS

Fifty-five cases of IUGR were observed, 30 of them were treated with CHM and 25 treated with amino acid for control.

RESULTS

The neonatal birth weight in the CHM group was markedly greater than that in the control group. Not only the maternal fundal height and abdominal circumference, but also the fetal growth parameters, including biparietal diameter, head circumference, abdominal circumference, femur length in the CHM group increased much faster than those in the control group. After CHM treatment, the maternal serum levels of estriol (E3) and human placental lactogen (hPL) were close to the normal pregnancy group, but the levels in the control group were significantly different from the normal range. The umbilical venous plasma concentration of essential amino acids was markedly improved after treatment, however, the improvement in the CHM group was more significant than that in the control group. No adverse effect of CHM was found both in mother and fetus.

CONCLUSION

CHM for supplementing Kidney and Qi, and activating blood circulation was more effective in the improvement of placental function and amino acid transportation than those of amino acid.

Epidemiological study of the risk factors of rampant caries in Shanghai children

OBJECTIVE

To explore the risk factors associated with rampant caries and to provide suggestions for prevention and clinical treatment.

METHODS

On the basis of a field survey, case-control study was performed to isolate variables possibly related to rampant caries in children. Data analysis was performed with individual analysis and multiple unconditional logistic regression. Four logistic models were developed.

RESULTS

The risk factors of rampant caries were cariogenic foods and bottle-feeding with sugar containing bovine milk; an increased risk of caries was also associated with duration of breast-feeding.

CONCLUSION

Overuse of cariogenic foods and unsuitable patterns of infant feeding were the most important risk factors associated with rampant caries.

Thermodynamic contribution of nucleoside modifications to yeast tRNA(Phe) anticodon stem loop analogs

The determination of the structural and functional contributions of natural modified nucleosides to tRNA has been limited by lack of an approach that can systematically incorporate the modified units. We have produced a number of oligonucleotide analogs, of the anticodon of yeast tRNA(Phe) by, combining standard automated synthesis for the major nucleosides with specialty chemistries for the modified nucleosides. In this study, both naturally occurring and unnatural modified nucleotides were placed in native contexts. Each oligonucleotide was purified and the nucleoside composition determined to validate the chemistry. The RNAs were denatured and analyzed to determine the van't Hoff thermodynamic parameters. Here, we report the individual thermodynamic contributions for Cm, Gm, m1G, m5C, psi. In addition m5m6U, m1psi, and m3psi, were introduced to gain additional understanding of the physicochemical contribution of psi and m5C at an atomic level. These oligonucleotides demonstrate that modifications have measurable thermodynamic contributions and that loop modifications have global contributions.

[Evaluation of therapeutic effects of portoenterostomy: reported of 426 cases]

OBJECTIVES

To investigate the selection of the types of anastomosis and to evaluate the therapeutic effects of portoenterostomy.

METHODS

From 1993 to 1998, 426 patients with obstructive jaundice underwent portoenterostomy. The patients included 236 cases (56%) of hilar strictures in hepatolithiasis, 98 cases (23%) of end-stage periampullary tumors, 64 cases (15%) of proximal cholangiocarcinoma, and 28 cases (6%) of congenital choledochus cyst. Reconstruction of biliary tract was performed after resection of affected duct or palliative bypass for end-stage carcinoma. The types of anastomosis included extra or hilar hepatic bilioenterostomy (160 cases, 37%), and intra-hepatic duct anastomosis with different type of hepatectomy (266 cases, 63%), in which anastomosis was performed by round ligament approach (34 cases, 8%), and anastomosis through gallbladder fossa (15 cases, 4%).

RESULTS

Short- and 1-6 year follow-up showed that jaundice of patients was completely relieved by suitable type of bilioenterostomy.

CONCLUSIONS

The good therapeutic effects of bilioenterostomy are based on the correct selection of anastomosis methods.

Five new triterpene saponins from Pulsatilla patens var. multifida

Five new oleanane-type glycosides (1-5), along with two known triterpene saponins, were isolated from the roots of Pulsatilla patens var. multifida (Ranunculaceae). The structures of the new triterpene saponins were elucidated as 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-galactopyranosyl hederagenin 28-O-beta-D-glucopyranosyl ester (1), hederagenin 3-O-[beta-D-glucopyranosyl(1-->2)][beta-D-glucopyranosyl(1-->6)]-beta -D-galactopyranoside (2), 3-O-beta-D-glucopyranosyl bayogenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (3), 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-galactopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (4), and 3-O-[beta-D-glucopyranosyl(1-->2)][beta-D-glucopyranosyl(1-->6)]-beta -D-galactopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (5). Structure elucidation was accomplished by 1D and 2D NMR (HMQC, HMBC, and ROESY) methods, FABMS, and hydrolysis.

Clinicopathological factors predicting retroperitoneal lymph node metastasis and survival in endometrial cancer

BACKGROUND

By clarifying the significance of clinicopathological factors for retroperitoneal lymph node metastasis and survival of patients with endometrial cancer, we suggest ideas for optimal treatment of this disease.

METHODS

A retrospective study was conducted in 310 women with endometrial cancer who underwent surgery with retroperitoneal lymphadenectomy. To evaluate retroperitoneal lymph node metastasis, age-adjusted and multivariable analyses were carried out for six clinicopathological factors including pathological grade, myometrial invasion, cervical invasion, peritoneal cytology, lymphatic permeation and vascular invasion. To evaluate survival, besides the above factors, a positive rate of metastasis of dissected retroperitoneal lymph nodes was included.

RESULTS

In 40 patients (13%) with nodal metastasis, the average positive rate of metastasis of dissected retroperitoneal lymph nodes was 22%. For retroperitoneal lymph node metastasis, the odds ratio of deep myometrial invasion, cervical invasion and severe lymphatic permeation were 5.97, 2.72 and 12.01, respectively. For survival, the hazard ratios of the positive rates of metastasis of dissected retroperitoneal lymph nodes (both 25% and < 25%), positive peritoneal cytology and poor pathological grade were 7.10, 3.24, 3.82 and 3.27, respectively, and 5-year survival rates for them were 0, 50, 72 and 77%, respectively.

CONCLUSIONS

For retroperitoneal lymph node metastasis, lymphatic permeation, deep myometrial invasion and cervical invasion were the independent prognostic factors. For survival, retroperitoneal lymph metastasis, poor pathological grades and positive peritoneal cytology were the independent prognostic factors. The positive rate of metastasis of dissected retroperitoneal lymph metastasis plays an important role in predicting survival of endometrial cancer. Lymph node biopsy is insufficient in treatment of this disease.

[Surgical treatment of aortopulmonary septal defect]

OBJECTIVE

To study the surgical treatment of aortopulmonary septal defect.

METHOD

From January 1983 to December 1996, 5 patients with aortopulmonary septal defect (APSD) (2 male and 3 female) aged from 6 to 34 years (mean 17.4 years) underwent surgical treatment. According to Mori's were classification, 5 patients belonged to type I, 2 type II and 1 type III. The diameters of the defect ranged from 1.0 to 3.0 cm. The operations were performed under moderate hypothermic cardiopulmonary bypass. Pulmonary artery incision was performed, in 3 patients while aortic incision in the other 2. All defects were repaired by Dacron patch.

RESULT

There were no operative deaths and postoperative complications. During follow-up of 10 months to 12 years, no late complications and deaths were found.

CONCLUSION

The operation should be done early as possible whenever the diagnosis is established. The surgical repair should be taken under cardiopulmonary bypass. To chose an incision on the aorta is more reasonable than on the pulmonary artery. The use the dacron patch can prevent stenosis and recanalization after operation.

[Determination of acetylcholine and choline in microdialysates from rat brain by high performance liquid chromatography with electrochemical detection combined with a post-column immobilized enzyme reactor]

In the present work, acetylcholine(ACh) and choline(Ch) in the microdialysates from three brain areas of anesthetized rats and from hippocampus and frontal cortex of freely moving rats were simultaneously measured by high performance liquid chromatography(HPLC) with electrochemical detection combined with a post-column immobilized enzyme reactor(IMER). This assay was based on the separation of ACh and Ch on a polymer gel column followed by passage of the effluent through an IMER, on which the separated ACh and Ch reacted respectively to give each stoichiometric yield of hydrogen peroxide, which was detected electrochemically at a platinum electrode (potential + 0.5 V versus Ag/AgCl). The tip of concentric dialysis probe was made of the semipermeable dialysis membrane of 0.22 mm in outside diameter, and the effective length inserted into rat brain was 3.0 mm. The probe was perfused at a rate of 1 microL/min with Ringer's solution which contained 10 mumol/L (for anesthetized rats) or 1 mumol/L (for freely moving rats) neostigmine, a reversible cholinesterase inhibitor, to elevate ACh level in microdialysate. Before the experiment, the recovery of the probe in vitro was measured at room temperature, and the position of the probe was checked by histological procedure at the end of the experiment. In the range of 0.2-100 mumol/L, the relation between the amounts and the peak areas was linear (r = 0.9988 for ACh and r = 0.9985 for Ch). The detection limit for ACh and Ch, at a S/N ratio of two, was found to be 50 fmol per injection. The probe recoveries(%) for ACh and for Ch were 23.2 +/- 1.4 and 34.3 +/- 3.2(mean +/- SD) respectively. The basal levels of ACh in the microdialysates from striatum and frontal cortex of anesthetized rats as well as from hippocampus and frontal cortex of freely moving rats were 212 +/- 28 and 22 +/- 4 as well as 26 +/- 4 and 83 +/- 7(nmol/L, mean +/- SD, not corrected according to probe recovery) respectively. The perfusion of high concentration K+ (100 mmol/L) through the dialysis probe induced a large increase of ACh in the microdialysates. The critical points for HPLC analysis combined with IMER were briefly discussed.

Mortality and cancer incidence in Misasa, Japan, a spa area with elevated radon levels

A historical cohort study was conducted in Misasa town, Tottori prefecture, Japan, where radon spas have been operating for a long time. Misasa town was divided into an elevated radon level area and a control area, with mean indoor radon levels of about 60 and 20 Bq/m3, respectively. In total, 3,083 subjects in the elevated radon level area and 1,248 in the control area, all aged 40 or older on January 1, 1976, were followed up until December 31, 1993, for a mean period of 14 years. The mortality rates from all causes exhibited no difference between the elevated radon level area and the control area for both sexes. No difference was observed in the incidence of all-site cancers (age, period-adjusted rate ratios by Poisson regression, RR = 1.06, 95% confidence interval (CI) 0.79-1.42 for males, RR = 0.90, 95% CI 0.65-1.24 for females), while stomach cancer incidence seemed to decrease for both sexes (RR = 0.70, 95% CI 0.44-1.11 for male, RR = 0.58, 95% CI 0.34-1.00 for female) and lung cancer incidence for males only seemed to increase (RR = 1.65, 95% CI 0.83-3.30 for male, RR = 1.07, 95% CI 0.28-4.14 for female) in the elevated radon level area. Caution is needed in the interpretation of these findings, however, since the individual exposure level was not measured and major confounding factors, such as smoking and diet, could not be controlled in this study.

[Comparative study on the effect of gossypol and T7 on human spermatozoa ATPase activity]

OBJECTIVE

A comparative study was carried out on the effect of two kinds of male contraceptive drugs, gossypol and the abstract of tripterygium wilfordii T7, on the human spermatozoa ATPase activity.

METHODS

The specific activity of total ATPase and Na-K ATPase of spermatozoa was assayed in this experiment.

RESULTS

(1) The effect of gossypol on the human spermatozoa ATPase activity is inhibitory and concentration-dependent; and (2) The abstract of tripterygium wilfodii T7 has no effect on the human spermatozoa ATPase activity.

CONCLUSIONS

The antifertility effects of gossypol and T7 are different.

[Excimer laser in situ keratomileusis for treatment of myopia]

OBJECTIVE

To evaluate the effectiveness of excimer laser in situ keratomileusis (LASIK) for treatment of myopia.

METHODS

928 eyes of 678 myopic patients who received LASIK were studied. The patients were divided into 3 groups according to preoperative diopters (-2.00 - -6.00D, -6.10 - -10.00D & -10.10 - -20.00D). The mean follow-up was 12 months (6 - 18 months) and the results were statistically analyzed.

RESULTS

12 months after surgery, in the first group the mean residual refraction was -0.24 +/- 0.50D in 86% and 92% of eyes were in the ranges of refraction +/- 0.50D and +/- 1.00D, the uncorrected visual acuities of 0.5 and 1.0 were in 99% and 86% of the eyes respectively. In the second group, the mean residual refraction was -0.47 +/- 0.64D, the refraction of 83% and 90% of eyes was in the ranges of +/- 0.50D and +/- 1.00D, and the uncorrected visual acuities in 95% and 79% of eyes were 0.5 and 1.0 respectively. In the third group, the mean residual refraction was -0.89 +/- 1.02D, the refraction of 36% and 62% of the eyes were in the ranges of +/- 0.50D and +/- 1.00D, and the uncorrected visual acuities in 68% and 45% of the eyes were 0.5 and 1.0 respectively. 47 eyes had been retreated with LASIK. 5 eyes lost two or more lines of the best corrected visual acuity due to irregular astigmatism, decentration and progressive myopic maculopathy.

CONCLUSION

The results indicate that LASIK can treat myopia in the range of -2.00 - -20.00 D effectively without vision threatening complications. Some modification of the surgical techniques and laser nomogram will help to improve predictability and stability of outcome.

Inhibition of TNFalpha attenuates infarct volume and ICAM-1 expression in ischemic mouse brain

The purpose of our study was to determine whether inhibiting the action of tumor necrosis factor-alpha (TNFalpha) attenuates brain injury and reduces inflammatory responses in the mouse during ischemia and reperfusion. Mice underwent middle cerebral artery occlusion (MCAO) for 1 h followed by 23 h reperfusion. Monoclonal neutralizing anti-murine TNFalpha antibody (mAb) was administrated intraventricularly in the mouse with temporary MCAO. Infarct volume in the anti-TNFalpha mAb treated mice was significantly smaller than that in the control group (p < 0.05). The number of intercellular adhesion molecule-1 (ICAM-1)-positive vessels in the ischemic area of the anti-TNFalpha mAb-treated group was significantly less than that in the control group. Our study demonstrated that blocking TNFalpha reduced brain injury and attenuated ICAM-1 expression during transient cerebral ischemia.

[Study on quality evaluation of Chinese traditional patent medicine with chemical patterm recognition (I)]

In this paper, the quality of Wuji Baifeng pills was comprehensively evaluated by a method of chemical pattern recognition, all the samples were divided into three grades (good, middling and poor). This method can be popularized and applied to evaluate quality of other Chinese traditional patent medicines.

FGF and Shh signals control dopaminergic and serotonergic cell fate in the anterior neural plate

During development, distinct classes of neurons are specified in precise locations along the dorso-ventral and anterior-posterior axes of the neural tube. We provide evidence that intersections of Shh, which is expressed along the ventral neural tube, and FGF8, which is locally produced at the mid/hindbrain boundary and in the rostral forebrain, create induction sites for dopaminergic neurons in the midbrain and forebrain. The same intersection, when preceded by a third signal, FGF4, which is expressed in the primitive streak, defines an inductive center for hindbrain 5-HT neurons. These findings illustrate that cell patterning in the neural plate is a multistep process in which early inducers, which initially divide the neural plate into crude compartments, are replaced by multiple local organizing centers, which specify distinct neuronal cell types within these compartments.

Pulsatilloside C from the roots of Pulsatilla chinensis

A new lupane-type triterpene saponin, pulsatilloside C (1), was isolated from the roots of Pulsatilla chinensis. Its structure was established to be 3beta,23-dihydroxylup-20(29)-en-28-oic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)- beta-D-glucopyranoside.

Ribosomal binding of modified tRNA anticodons related to thermal stability

The physicochemical contributions of modified nucleosides to tRNA functions are not well understood. In order to determine the contributions of specific modifications to tRNA stability as well as to ribosomal binding, ten variously modified yeast tRNA(Phe) anticodon stems and loops (tRNA(Phe)AC) were synthesized. Thermal denaturation studies on these synthetic 17mers show dramatic stabilization (or destabilization) by the presence of the various naturally occurring nucleoside modifications. Adapting a novel molecular biology approach (initially pioneered by Moazed and Noller), the interactions of these variously modified anticodons with the E. coli 16S rRNA "P-site" residues are being quantitated. The binding (affinity) constant (kD) of the tRNA(Phe)AC to the 8 of the ten 16S rRNA nucleosides that interact with tRNA and synthetic anticodons are being examined. We postulate that the "stabilizing" modifications (m1G37, psi 39, and m5C40) in the presence of an "open loop" will dramatically increase the binding affinity of the tRNA(Phe)AC to the 30S E. coli ribosomal subunit when compared to unmodified tRNA(Phe)AC. On the other hand, "destabilizing" modifications are expected to reduce the binding affinity of the tRNA(Phe)AC to the E. coli 30S ribosomal subunit. The results from these experiments have demonstrated the importance of nucleoside modifications to tRNA stability and ribosomal binding affinity, and will relate the structural contributions of nucleoside modifications to tRNA function.

[Hepatectomy for hepatolithiasis treatment of 354 cases]

OBJECTIVE

To evaluate the effect of hepatectomy for hepatolithiasis.

METHOD

354 patients with hepatolithiasis underwent hepatectomy in the past 10 years. The results were analysed retrospectively, including clinical findings, distribution of stones, patterns of operation, postoperative complications, and residual stones. The clinical data of the patients before 1990 were compared with those thereafter.

RESULT

Left hepatolithiasis was the most common form (323 patients). Left lateral lobectomy and left hepatectomy were most commonly employed (91.2%). 166 of the patients underwent concurrent cholangiojejunostomy. 13.8% patients had residual stones, and postoperative complications occurred in 60 patients, including 4 deaths. Few patients were reoperated on and the incidence of residual stones was lower after 1990. 88% the patients showed excellent or good result.

CONCLUSION

Hepatectomy is a procedure for the management of hepatolithiasis, but still requires combined plasty of stenotic intrahepatic bile ducts and cholangiojejunostomy to reduce the incidence of residual stones and recurrence.

[A case-control study on diet and gastric cancer]

OBJECTIVE

To study the relationship between consumption of fish sauce, diet, living-habit and risk of gastric cancer.

METHODS

A population-based 1:2 matched case-control study was conducted in Changle and Fuqing Cities of Fujian Province during May 1994 to July 1995. Totally, 272 matched pairs were investigated.

RESULTS

Risk state single-factor analysis indicated that there were significant associations between occurrence of gastric cancer and over consumption of fish sauce (OR = 2.57), pickled vegetables (OR = 1.41) and sea food (OR = 1.57), low consumption of fresh vegetables (OR = 1.95), citrus fruits (OR = 1.41), other fruits (OR = 1.31) and green tea (OR = 1.72), exposure to moldy cereals (OR = 2.32), taking meals at irregular times (OR = 5.47) and familial history of malignancy (OR = 3.27). No associations between risk of gastric cancer and smoking, alcohol drinking, amount of salft consumption, use of refrigerator were found. Analysis of risk state conditional logistic regression showed that fish sauce, pickled sea food, irregularly taking meals and familial history of malignancy were included in a set of risk factors for gastric cancer, with a summary attributable risk percentage of 75.49%.

CONCLUSION

Over consumption of fish sauce, pickled food, moldy cereals, irregularly taking meals and familial history of malignancy may be the local risk factors for high occurrence of gastric cancer, and fresh vegetables and fruits, green tea may have protective effects on it.

Matrix metalloproteinase inhibitors: a structure-activity study

Modifications around the dipeptide-mimetic core of a hydroxamic acid based matrix metalloproteinase inhibitor were studied. These variations incorporated a variety of natural, unnatural, and synthetic amino acids in addition to modifications of the P1' and P3' substituents. The results of this study indicate the following structural requirements: (1) Two key hydrogen bonds must be present between the enzyme and potent substrates. (2) Potent inhibitors must possess strong zinc-binding functionalities. (3) The potential importance of the hydrophobic group at position R3 as illustrated by its ability to impart greater relative potency against stromelysin when larger hydrophobic groups are used. (4) Requirements surrounding the nature of the amino acid appear to be more restrictive for stromelysin than for neutrophil collagenase, 72 kDa gelatinase, and 92 kDa gelatinase. These requirements may involve planar fused-ring aryl systems and possibly hydrogen-bonding capabilities.

[Study on GC fingerprint characteristic features of wuji baifeng pills]

In this paper, the fingerprint characteristic features that can be used for identification of Wuji Baifeng Pills were obtained by gas chromatographic analysis.

The non-uniform distribution of albumin in human and bovine cornea

In our previous studies, we noted a non-uniform distribution of protein tracer preferentially entering the anterior stromal lamellae of the cornea from the limbus. Given other differences reported previously between the anterior and posterior lamellae of the cornea, and the number of corneal disorders in which abnormalities are preferentially confined to either the anterior or posterior lamellae, we were prompted to examine the distribution of albumin in normal human and bovine cornea. The distribution of albumin in bovine and human cornea was studied immunohistochemically. Total soluble protein and albumin in the anterior 1/3 and posterior 2/3 of the central, middle and peripheral cornea of bovine eyes was measured biochemically. To aid in interpreting the findings, a theoretical model was developed based upon the combined effects of diffusive and convective transport. Using immunohistochemical methods, in both bovine and human eyes, intense staining of albumin was found in the anterior 1/3 of the corneal stroma. There was a gradual reduction in staining intensity from the limbus to the central cornea in the anterior corneal stroma. Less staining was found in the posterior 2/3 of corneal stroma. Additionally, a greater concentration of soluble protein and albumin was found in the anterior stroma than in the posterior stroma of the bovine eyes by biochemical analyses. The theoretical model demonstrated that this distribution of protein required a difference in excluded volume fraction between the anterior and posterior stroma and was consistent with a convective flux originating at the limbus and passing through the corneal stroma. The soluble proteins of the bovine and human cornea are preferentially concentrated in the anterior cornea and near the limbus. This distribution is likely due to differences in excluded volume fraction between the anterior and posterior stroma and a small convective flux passing through the cornea.

Signal model of noise in open-loop fiber-optic gyros

The characteristics of noise in fiber-optic gyros are analyzed quantitatively. Based on its physical characteristics and on autocorrelation function evidence, the noise is modeled as the addition of fractal Brownian motion (FBM) and Gaussian white noise (GWN). The value of self-similarlity parameter H in FBM and the intensity of GWN, sigma(w), in the model are robustly determined with an algorithm based on an orthonormal wavelet transform, which demonstrates well the coexistence of the long- and short-term correlation components of the gyro noise. Moreover, it is revealed that FBM dominates the gyro noise, whereas the GWN is minor.

Interendothelial junctions in normal human Schlemm's canal respond to changes in pressure

PURPOSE

To determine if changes in the structure and complexity of junctions between endothelial cells lining Schlemm's canal (SC) occur in normal human eyes with changes in perfusion pressure.

METHODS

Twelve normal human eyes were either perfusion-fixed (at 15 or 45 mm Hg) or immersion-fixed (0 mm Hg) in modified Karnovsky's fluid. 'Outflow facility was measured continually during the perfusion fixation. The intercellular junctions of the endothelial cells of SC were ultrastructurally examined in thin sections, including serial sections and freeze-fracture replicas. Morphometric data on the number of junctional strands per total length of tight junction were documented and categorized by the number of strands (one, two, or three or more). The length of endothelial cell overlap was measured on thin sections.

RESULTS

In freeze-fracture replicas, perfusion-fixed eyes demonstrated less complex junctions. At 15 mm Hg, 18.06% of the total junctional length was represented by three or more strands; at 45 mm Hg, this percentage decreased to 8.59%. In immersion-fixed eyes, 24.17% of the total junctional length was represented by three or more strands. These differences were statistically significant (P < 0.0012). In sections, the amount of endothelial cell overlap, and thus the length of paracellular pathway, was reduced in perfusion-fixed versus immersion-fixed eyes (P < 0.02). Extensive serial sectioning demonstrated that giant vacuoles were formed, either by individual endothelial cells or by two or more adjacent endothelial cells.

CONCLUSIONS

When compared with specimens fixed at zero pressure, overlap between endothelial cells of SC is reduced significantly when this cell layer is under conditions of flow similar to those encountered in vivo. The tight junctions between cells of the inner wall of SC become less complex with increasing pressure. Our data suggest that the paracellular pathway into SC in the normal eye is sensitive to modulation within a range of physiologically relevant pressures.