Biomedical subjects

W Ye

Publications and source records attributed to W Ye.

At least 55 records · Page 3Linked to original sources

PubMed2001

Hepatic cytoreduction followed by a novel long-acting somatostatin analog: a paradigm for intractable neuroendocrine tumors metastatic to the liver.

BACKGROUND: Optimal management of symptomatic neuroendocrine tumors that metastasize to the liver is controversial. We investigated aggressive hepatic cytoreduction and postoperative administration of octreotide long-acting release (LAR), a long-acting somatostatin analog. METHODS: Between December 1992 and August 2000, 31 patients underwent hepatic surgical cytoreduction (20 carcinoid, 10 islet cell, and 1 medullary). All patients had progressive symptoms refractory to conventional therapy. RESULTS: Hepatic cytoreduction (resection, cryosurgery, and/or radiofrequency ablation) eliminated symptoms in 27 patients (87%) and decreased secretion of hormones by an overall mean of 59%. When minor symptoms returned and/or hormonal levels increased during follow-up, adjuvant therapy was started. Ten patients received adjuvant octreotide LAR once a month, and 21 received other adjuvants. At a median postoperative follow-up of 26 months, 16 patients had progressive/recurrent disease, 13 had died of their disease, and 2 remained free of disease. Median symptom-free interval was 60 months (95% confidence interval, 48-72) with octreotide LAR and 16 months (95% confidence interval, 10-29) with other adjuvants (P = .0007). Two-year symptom-free survival rate was 100% with octreotide LAR and 33% with other adjuvants. CONCLUSIONS: Hepatic surgical cytoreduction can palliate progressive symptoms associated with liver metastases from intractable neuroendocrine tumors. Postoperative adjuvant therapy with octreotide LAR can prolong symptom-free survival.

Adult↗

PubMed2001

Attenuation of ischemia-induced mouse brain injury by SAG, a redox-inducible antioxidant protein.

Cerebral ischemia resulting from a disruption of blood flow to the brain initiates a cascade of events that causes neuron death and leads to neurologic dysfunction. Reactive oxygen species are thought, at least in part, to mediate this disease process. The authors recently cloned and characterized an antioxidant protein, SAG (sensitive to apoptosis gene), that is redox inducible and protects cells from apoptosis induced by redox agents in a number of in vitro cell model systems. This study reports a neuroprotective role of SAG in ischemia/reperfusion-induced brain injury in an in vivo mouse model. SAG was expressed at a low level in brain tissue and was inducible after middle cerebral artery occlusion with peak expression at 6 to 12 hours. At the cellular level, SAG was mainly expressed in the cytoplasm of neurons and astrocytes, revealed by double immunofluorescence. An injection of recombinant adenoviral vector carrying human SAG into mouse brain produced an overexpression of SAG protein in the injected areas. Transduction of AdCMVSAG (wild-type), but not AdCMVmSAG (mutant), nor the AdCMVlacZ control, protected brain cells from ischemic brain injury, as evidenced by significant reduction of the infarct areas where SAG was highly expressed. The result suggests a rather specific protective role of SAG in the current in vivo model. Mechanistically, SAG overexpression decreased reactive oxygen species production and reduced the number of apoptotic cells in the ischemic areas. Thus, antioxidant SAG appears to protect against reactive oxygen species-induced brain damage in mice. Identification of SAG as a neuroprotective molecule could lead to potential stroke therapies.

Adenoviridae↗

PubMed2001

Risk of pancreatic cancer after cholecystectomy: a cohort study in Sweden.

BACKGROUND: Although some experimental studies have indicated that cholecystectomy may increase the risk of pancreatic cancer, data from epidemiological studies are conflicting. AIMS: We conducted a register based retrospective cohort study to explore the relationship between cholecystectomy and pancreatic cancer. SUBJECTS: The cohort included 87 263 men and 181 049 women with a documented cholecystectomy for cholelithiasis between 1965 and 1997. METHODS: By record linkage to the nationwide and virtually complete registers of Cancer, Emigration, and Causes of Death, the cohort was followed up until the occurrence of any cancer, emigration, death, or the end of follow up, 31 December 1997, whichever came first. Relative risk was estimated by standardised incidence ratio (SIR) using the Swedish nationwide sex, age, and calendar year specific cancer incidence rates as reference. RESULTS: During the period of observation, 1053 cases of pancreatic cancer were found, among which 231 (22%) occurred within 12 months after operation. After excluding cases and person years accrued during the first two years of follow up, we observed a non-significant 6% excess risk for pancreatic cancer (95% confidence interval (CI) -2 to 14%). The relative risk did not increase with increasing follow up duration, with a SIR equal to 0.98 (95% CI 0.79-1.20) 20 years or more after operation. Patients with a comorbidity of diabetes or chronic pancreatitis had higher relative risks (SIR=1.79, 95% CI 1.39-2.28; SIR=3.17, 95% CI 1.37-6.24, respectively). After excluding patients with recorded diabetes or chronic pancreatitis, the relative risk was close to unity (SIR=1.01, 95% CI 0.94-1.09). CONCLUSIONS: Our findings do not support the hypothesis that cholecystectomy increases the subsequent risk of pancreatic cancer.

Adult↗

PubMed2001

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

UNLABELLED: 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.

Adenoviridae↗

PubMed2001

Incidence of cancer among patients with hidradenitis suppurativa.

BACKGROUND: On the basis of some case reports, a relationship has been suggested between hidradenitis suppurativa (HS) and the development of nonmelanoma skin cancer. OBJECTIVES: To confirm this relationship and to explore the risk of other cancers among patients with HS. PATIENTS: Patients with a discharge diagnosis of HS were obtained from the computerized database of hospital discharge diagnoses from January 1, 1965, through December 31, 1997. A total of 2119 patients with HS were identified. SETTING: All hospitals in Sweden. DESIGN: With record linkage to the Swedish National Cancer Registry, standardized incidence ratios (SIR [the ratio of the observed to expected incidence]) were calculated to estimate relative risk. RESULTS: The risk of developing any cancer in the cohort with HS increased 50% (95% confidence interval of SIR, 1.1-1.8, based on 73 observed cases). Statistically significant risk elevations were observed for nonmelanoma skin cancer (5 cases; SIR, 4.6; 95% confidence interval, 1.5-10.7), buccal cancer (5 cases; SIR, 5.5; 95% confidence interval, 1.8-12.9), and primary liver cancer (3 cases; SIR, 10.0; 95% confidence interval, 2.1-29.2). CONCLUSIONS: This study confirms an increased risk of nonmelanoma skin cancer among patients with HS. The risk for buccal cancer and primary liver cancer was also elevated among this cohort, but these associations should be interpreted cautiously because the combination of multiple significance testing and the few observed cases may have generated chance findings.

Adult↗

PubMed2001

Alcoholism and risk for cancer of the cervix uteri, vagina, and vulva.

We conducted a population-based cohort study to analyze the risk of developing cancers of the female genitals among 36,856 patients with a hospital discharge diagnosis of alcoholism (ICD-7: 307, 322; ICD-8: 291, 303; ICD-9: 291, 303, 305A) in Sweden between 1965 and 1995. The follow-up was done by linkages of national registries. Standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) were computed based on nationwide specific cancer rates. The first year of follow-up was excluded from all analyses to minimize the impact of selection bias. We found that alcoholic women had excess risks for in situ cervical cancer (SIR, 1.7; 95% CI, 1.6-1.9), for invasive cervical cancer (SIR, 2.9; 95% CI, 2.4-3.5), and for cancer of the vagina (SIR, 4.6; 95% CI, 2.2-8.5) but not for cancer of the vulva (SIR, 1.0; 95% CI, 0.4-2.0). The fact that alcoholics had an excess risk also for the in situ cancer suggests that the observed excess in invasive cervical cancer may not only be attributable to less use of Pap smear screening among them. The alcoholic women may be at higher risk for the progression from human papillomavirus infection to a malignant lesion for lifestyle-related reasons (promiscuity, smoking, use of contraceptive hormones, and dietary deficiencies). We conclude that alcoholic women are at high risk for in situ and invasive cervical cancer and for cancer of the vagina.

Adult↗

PubMed2001

[The relation between expression of basic fibroblast growth factor and mast cells in pterygium].

OBJECTIVE: To examine the expression and distribution of basic fibroblast growth factor (bFGF) and mast cells in pterygium, and evaluate its effects in the pterygium formation and progression. METHOD: The expression of bFGF and mast cell tryptase in 17 primary pterygia, 6 recurrent pterygia and 6 normal conjunctival specimens were studied. The mast cell count and bFGF expression situation were observed. RESULTS: The bFGF was specifically localized in the epithelium, blood vessels and a subset of connective tissue cells. The bFGF expression was increased in the recurrent pterygium. The numbers of infiltrating mast cells (five 400 x sights) were (45.47 +/- 5.50) cells and (48.83 +/- 3.19) cells in the primary and recurrent pterygium respectively. In the comparisons between the cells in the pterygium (primary and recurrent) and (4.24 +/- 2.36) cells in the normal connective tissue, there were significant differences (F = 200.3128; q = 26.6762, 23.7341; P < 0.05). The shape and distribution of all the tryptase-positive cells (mast cells) in the pterygium tissues were similar to that of the cells with bFGF expression in the connective tissue. And the majority of bFGF-positive cells (87.54 +/- 3.60)% were similar to that of mast cells in the connective tissue. CONCLUSIONS: All infiltrating mast cells in pterygium have bFGF-positive expression. The bFGF expression is increased in the epithelium, blood vessels and infiltrating mast cells of the pterygium, and may contribute to the formation and progression of a pterygium.

Adult↗

PubMed2001

[Genomic structure and proteins sequence analysis of full-length of segment A of three infections bursal disease viruses].

The full-length of segment A of three infectious bursal disease viruses (IBDV), including an attenuated strain HZ2, an attenuated vaccine strain JD1 and a virulent field isolate ZJ2000, were cloned by long RT-PCR and sequenced respectively. All the three results revealed the identity of IB-DV with two overlapping open reading frames (ORF) flanked by 5'- and 3'-noncoding regions(NCR) in 3259 bp long. The strains shared high identity with each other at nucleotide or deduced amino acid level, and also had four unique sites H253, N279, T284, R330 which are common in other attenuated and some classic or highly virulent strains. The virulent strain ZJ2000 had several key amino acid mutations located in hypervariant region of VP2 and near the VP2-VP4 cleavage site of polypeptide, which is probably related to the virulence. Sequence comparison supported that VP2 is not the sole determinant of the virulence. The highly conservation in 5'- and 3'-NCR of different strains indicated the NCR may be not responsible for the virulence. But the same conservation appeared in VP5 revealed another complex relationship between VP5 and the virulence.

Amino Acid Sequence↗

PubMed2001

[The effect of frozen storage for amniotic membrane ultrastructure].

OBJECTIVE: To observe the effect of frozen storage for amniotic membrane ultrastructure, and provide the experimental evidence for clinical use. METHODS: The amniotic membranes of fresh-obtained and -80 degrees C frozen storage 30 d, 60 d, 90 d and 180 d were examined with transmission electron microscope, and the ultrastructural changes were observed. RESULTS: The epithelium in the fresh-obtained amniotic membrane was observed as intact structure, abundant organelles in cytoplasm and intercellular contact with desmosome. A great quantity of collagen micro-fibrils were found in the stroma, and the light and shade striation were observed in the collagen micro-fibrils of fresh-obtained amniotic membrane. The epithelium degenerated and died gradually as the increase of frozen storage time. At the frozen storage of 90 days, the epithelial chromatin dissolved, organelles degenerated and mitochondrion vacuolated. At the frozen storage of 30 days and 60 days, the pattern of collagen micro-fibrils in stoma was similar to that in fresh-obtained amniotic membrane; At the frozen storage of 90 days, some of collagen micro-fibrils in stoma showed intumescence. At the frozen storage of 180 days, the number of collagen micro-fibrils in stoma decreased, and some of them showed intumescence and dissolvent. CONCLUSION: Frozen storage can result in amniotic membrane epithelium death and collagen micro-fibrils intumescence and dissolvent.

Adult↗

PubMed2001

[Preliminary study on relationship between TCM syndrome-type and insulin resistance in coronary heart disease].

OBJECTIVE: To observe the relationship between TCM Syndrome-type and insulin resistance (ISR) in coronary heart disease (CHD). METHODS: Fifty patients were divided into 3 groups according to the Syndrome Differentiation-typing in TCM, the Heart blood stasis (HBS) Syndrome group, the Phlegm-Turbid stagnation (PTS) Syndrome group and both Qi-Yin Deficiency (QYD) Syndrome group. The fasting blood glucose (FBG), fasting blood insulin (Ins), insulin antibody (IAA), islet cell antibody (ICA), glutamic acid decarboxylase antibody (GAD-Ab) and related blood lipid parameters in patients were determined and insulin sensitive index (ISI) was calculated simultaneously. Then the above-mentioned data were compared with those determined in 20 healthy control subjects. RESULTS: The levels of FBG and Ins in CHD group were higher than those in healthy control group significantly (P < 0.05), but ISI level was obviously lower (P < 0.01). Moreover, the positive ratio of IAA (40%) was higher in CHD group than that in the control group (5%) significantly (P < 0.01). Comparison between the 3 TCM Syndrome-type groups and the control group showed that ISI level in HBS and PTS group was obviously lower than that in the control and the QYD (P < 0.05) respectively, and the IAA positive ratio in the former 2 groups (50%, 47.3%) was higher than that in the later two (5%, P < 0.01 and 15.38%, P < 0.05) markedly. While Ins level increased only in the HBS group (P < 0.05). Besides, patients of HBS and PTS were accompanied by lipid metabolic disturbance. CONCLUSION: ISR presents in part of CHD patients particularly in those with HBS and PTS, which was partly due to the existence of IAA in patients serum.

Adult↗

PubMed2001

[An epidemiological study of risk factors of rampant caries in Shanghai children].

OBJECTIVE: To explore the risk factors of rampant caries in order to provide suggestion to prevention and clinical treatment. METHODS: A case control study and logistic regression were performed to observe some variables that possibly related to rampant caries in children on the base of a field survey. RESULTS: The risk factors of rampant caries were incepting cariogenic foods too much and bottle feeding with sugar containing bovine milk. The risk of suffering from rampant caries also increased with duration of breast feeding. CONCLUSION: Incepting cariogenic foods too much and unappropriate patterns of infant feeding were the important risk factors of rampant caries.

English Abstract↗

PubMed2000

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.

Journal Article↗

PubMed2000

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.

Adult↗

PubMed2000

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.

Adenocarcinoma↗

PubMed2000

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.

Adenocarcinoma↗

PubMed2000

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.

Animals↗

PubMed2000

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.

Animals↗

PubMed2000

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.

Amino Acid Substitution↗