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At least 505 records · Page 28Linked to original sources
PubMed2004

Randomized, double-blind, controlled trial of mifepristone in capsule versus tablet form followed by misoprostol for early medical abortion.

OBJECTIVE: To compare the efficacy and side-effects of mifepristone 75 mg in capsule form versus 150 mg in tablet form followed by misoprostol for medical termination of early pregnancy. STUDY DESIGN: In a prospective randomized, double-blind, placebo-controlled trial, a total of 480 women who were 49 days or less pregnant were randomized by means of a random number table to receive either two tablets in the morning and one tablet 12 h later for 2 days (group A) or three capsules orally twice daily for 2 days, the first dose being double all subsequent doses (group B). After a further 48 h, 600 microg misoprostol was given orally. Successful abortion was defined as complete abortion with no need for surgical aspiration. RESULTS: There were no significant differences between the two study groups in the rates of complete abortion (95.4% in group A versus 96.3% in group B), incomplete abortion (3.8% in group A, 3.3% in group B) and continued pregnancy (0.8% in group A, 0.4% in group B). No significant difference in the duration and amount of vaginal bleeding was observed. The incidence of side-effects, such as vomiting, nausea, headache, diarrhea and lower abdominal pain was similar in the two groups. CONCLUSIONS: Our results indicate that 75 mg mifepristone in capsule form combined with 600 microg misoprostol is as effective and safe as 150 mg mifepristone in tablet form for the termination of pregnancy up to 49 days.

Abortifacient Agents, Nonsteroidal↗
PubMed2006

Nobiletin, a citrus flavonoid, suppresses phorbol ester-induced expression of multiple scavenger receptor genes in THP-1 human monocytic cells.

Unregulated uptake of oxidized low-density lipoproteins (ox-LDL) via macrophage scavenger receptors (SRs) such as lectin-like ox-LDL receptor-1 (LOX-1) is a key event in atherosclerosis. In this study, we examined the effects of five selected food phytochemicals on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced LOX-1 mRNA expression in THP-1 human monocyte-like cells. Nobiletin, a citrus polymethoxylated flavone, markedly reduced it in dose- and time-dependent manners. It also suppressed the phosphorylation of extracellular signal-regulated protein kinase (ERK) 1/2, c-Jun NH2-terminal kinase (JNK) 1/2, and c-Jun (Ser-63), thereby inhibiting the transcriptional activity of activator protein-1. Further nobiletin attenuated expression of SR-A, SR-PSOX, CD36, and CD68, but not CLA-1, mRNA, leading to the blockade of DiI-acLDL uptake. Together, our results suggest that nobiletin is a promising phytochemical for regulating atherosclerosis with reasonable action mechanisms.

Carbocyanines↗
PubMed2026

Insights into the fate and dynamics of antibiotic resistance in multidrug-resistant Bacillus cereus during in vitro simulated gastrointestinal digestion.

Bacillus cereus, an important pathogen responsible for causing foodborne diseases worldwide, releases pore-forming enterotoxins, which target host epithelial cells, leading to osmotic lysis and ultimately manifesting as diarrheal syndrome. Moreover, some B. cereus strains carry antimicrobial resistance genes that confer multidrug resistance against a spectrum of antibiotics. Characterizing the survival traits of multidrug-resistant (MDR) B. cereus strains in the intestinal microenvironment is essential for developing targeted strategies to effectively manage diarrheal foodborne diseases caused by this pathogen. This study used whole-genome sequencing (WGS) to evaluate the pre- and post-digestion toxigenic potential, antimicrobial resistance profiles, and genetic diversity of MDR B. cereus strains isolated from food samples in Guangdong Province, China. The four B. cereus isolates investigated in this study exhibited a genetic diversity, as determined by multilocus sequence typing analysis of WGS data. All four isolates produced the diarrheal toxins Hbl, Nhe, and CytK to varying levels, indicative of their potential to cause outbreaks of foodborne diseases. Each of the four isolates exhibited resistance to more than three classes of antibiotics, fulfilling the criterion for multidrug resistance. At an initial concentration of 9 log colony-forming units (CFU)/mL, the intestinal concentration of these four isolates crossed the threshold required to induce widespread diarrhea in the general population. Under rice slurry protection, all tested isolates maintained intestinal concentration beyond the threshold when the initial concentration was increased to ≥8 log CFU/mL. Moreover, the upregulations of genes associated with acid tolerance, bile tolerance and stress response were observed in the surviving MDR B. cereus isolates. Digestion markedly altered the antibiotic resistance profiles of the MDR B. cereus isolates. In the absence of a food matrix, the MDR isolates lost their resistance to imipenem, meropenem, amoxicillin-clavulanic acid, and trimethoprim-sulfamethoxazole post-digestion and was influenced by the initial concentration of the strains. In the presence of food matrix rice slurry, the effects of digestion on the antibiotic resistance of MDR B. cereus isolates can be mitigated, enabling them to maintain their antibiotic resistance to the greatest extent. Most remarkably, after digestion, the isolates Bce055 and Bce166 exhibited newly emergent resistance to cefotetan and trimethoprim-sulfamethoxazole, respectively. Our findings clarify the fate of MDR B. cereus isolates in the gastrointestinal tract and inform the development of prevention and control strategies for foodborne diseases caused by this pathogen.

Drug Resistance, Multiple, Bacterial↗
PubMed2005

Protective effects of antimicrobial peptides derived from the beetle Allomyrina dichotoma defensin on endotoxic shock in mice.

Synthetic peptides, Arg-Leu-Tyr-Leu-Arg-Ile-Gly-Arg-Arg-NH2 (peptide A) and Arg-Leu-Arg-Leu-Arg-Ile-Gly-Arg-Arg-NH2 (peptide B), derived from the beetle Allomyrina dichotoma defensin, have not only antimicrobial activities but also anti-inflammatory effects by inhibiting tumour necrosis factor-alpha(TNF-alpha) production. In the present study, we evaluated the lipopolysaccharide (LPS)-binding activities and the protective effects of these peptides on LPS-induced lethal shock in d-galactosamine (GalN)-sensitized mice. These peptides were shown to bind to erythrocytes coated with LPS and the binding activity of peptide A to LPS was significantly higher than those of peptide B and polymyxin B. Mice were injected intraperitoneally with peptide A or B at doses of 25, 50, 100 and 150 mg/kg before an injection of Salmonella abortusequi LPS (5 microg/kg) and GalN (1 g/kg) (LPS+GalN). All of wild-type mice died within 24 h after challenged with LPS+GalN. All of TNF-alpha-deficient mice challenged with LPS+GalN survived. An injection of peptide A immediately after challenge with LPS+GalN resulted in significantly improved survival rates in a dose dependent manner. Peptide B showed only minor protection. The levels of TNF-alpha in the ameliorated mice by peptide A were significantly lower than those of challenge control, suggesting a suppressive effect of peptide A on TNF-alpha production. Furthermore, peptide A-treated mice showed significantly lower levels of asparate aminotransferase and alanine aminotransferase when compared to challenge control. Concordantly, hemorrhage and necrosis in the liver of peptide A-treated mice were less apparent than those of untreated control mice. These results suggest that peptide A has a protective effect on LPS-induced mortality in this mouse model.

Agglutination↗
PubMed2002

Within-herd use of boar semen at 5 degrees C, with a note on electronic monitoring of oestrus.

A system was designed to allow a small swine farm in a northern latitude to use its own boars for artificial insemination (AI) conveniently. Semen was collected twice weekly for 3 day use (days 0, 1 and 2), extended in an egg yolk extender and stored at 5 degrees C. Farm personnel were trained to manage the entire AI programme. For simplicity all semen collected was used for insemination. In the first test 47 gilts and 15 sows were inseminated with semen from four boars. One boar was subfertile with a farrowing rate of 36%. The averages for the other boars ranged from 71 to 100%. Then semen was collected from seven boars and all was used to inseminate 70 gilts and 55 sows with 3 x 10(9) or more sperm. Overall 63% farrowed an average of 10.1 piglets per litter. Litter size for sows was 1.5 piglets larger than for gilts. There was no difference in farrowing rate when more than 3 x 10(9) sperm were inseminated. The feasibility of initiating a complete AI programme within a small herd using herd boars was established. However, selection of the boars, use of only high quality semen, and experience with detecting oestrus was required to increase the farrowing rate. The use of various agents to protect sperm against cold shock below 15 degrees C is worthy of further investigation. A new type of electronic probe, which measures the conductivity of cervical mucus, could be helpful if a boar is not available for conventional detection of oestrus.

Animals↗
PubMed2004

Probucol inactivates ABCA1 in the plasma membrane with respect to its mediation of apolipoprotein binding and high density lipoprotein assembly and to its proteolytic degradation.

Probucol has been shown to inhibit the release of cellular lipid by helical apolipoprotein and thereby to reduce plasma high density lipoprotein. We attempted to explore the underlying mechanism for this effect in human fibroblast WI-38. Probucol inhibited the apoA-I-mediated cellular lipid release and binding of apoA-I to the cells in a dose-dependent manner. It did not influence cellular uptake of low density lipoprotein, transport of cholesterol to the cell surface whether de novo synthesized or delivered as low density lipoprotein, and overall cellular content of cholesterol, although biosynthesis of lipids from acetate was somewhat increased. Probucol did not affect the mRNA level of ABCA1, and ABCA1 was recovered along with marker proteins for plasma membrane regardless of the presence of probucol. However, the protein level of ABCA1 increased, and the rate of its decay in the presence of cycloheximide was slower in the probucol-treated cells. ABCA1 in the probucol-treated cells was resistant to digestion by calpain but not by trypsin. We concluded that probucol inactivates ABCA1 in the plasma membrane with respect to its function in mediating binding of and lipid release by apolipoprotein and with respect to proteolytic degradation by calpain.

ATP Binding Cassette Transporter 1↗
PubMed2005

[Growth-inhibiting and anti-metastasis effects of Weichang'an Decoction on orthotopic transplant nude mouse model of human gastric cancer].

OBJECTIVE: To evaluate the growth-inhibiting and anti-metastasis effects of Weichang'an Decoction (WCAD) on orthotopic transplant nude mouse model of human gastric cancer. METHODS: Forty-one nude mice were implanted with SGC-7901 cells at orthotopic site, whereas 25 were implanted with SGC-7901 cells subcutaneously. Then the nude mice in each transplantation model were divided into the same three groups which were WCAD-treated group with WCAD 0.5 ml/d taken orally, 5-FU-treated group with 5-FU 50 mg/kg intraperitoneally injected weekly and untreated control group with physiological saline 0.5 ml/d taken orally. The growth-inhibiting rates of transplant tumors were detected and the metastatic lesions were examined in the orthotopic transplant mouse model while PCNA-positive rate and apoptotic index (AI) were observed in the subcutaneous transplant mouse model. RESULTS: The growth-inhibiting rates in the WCAD-treated and 5-FU-treated groups of orthotopic transplant mouse model were 40.82% and 37.92% respectively whereas those of subcutaneous transplant mouse model were 48.70% and 60.10%. The incidence rates of metastasis in perigastric lymph notes, lymph nodes in the porta hepatis, liver, diaphragm and peritoneum in the WCAD-treated and 5-FU-treated groups were lower than those in the untreated control group, and the total metastasis rates in the WCAD-treated, 5-FU-treated and the untreated control groups were 30.77%, 28.57% and 71.43% respectively with significant differences (P<0.05). The total PCNA-positive rates in the WCAD-treated and 5-FU-treated groups were obviously lower than that in the untreated control group (P<0.05 or P<0.01) while the AI was higher than that in the untreated control group (P<0.01). The growth-inhibiting rate, total PCNA-positive rate and total metastasis rate in the WCAD-treated group had no significant differences as compared with those in the 5-FU-treated group, but the AI in the WCAD-treated group was significantly higher than that in the 5-FU-treated group (P<0.05). CONCLUSION: WCAD has the inhibiting effects on tumor growth and metastasis of gastric cancer which is orthotopic implanted onto nude mice. This effect may be obtained by proliferation suppression and apoptosis induction in cancer.

Animals↗
PubMed2002

Resveratrol induced serine phosphorylation of p53 causes apoptosis in a mutant p53 prostate cancer cell line.

PURPOSE: Resveratrol (Calbiochem, La Jolla, California) is a naturally occurring stilbene reported to cause apoptosis in various cultured cancer cells. In the current study the effect of resveratrol was determined in the androgen insensitive DU 145 prostate cancer cell line. Induction of apoptosis and activation of apoptosis related signal transduction pathways were measured. MATERIALS AND METHODS: DU 145 cells were treated with resveratrol and apoptosis was measured by determining nucleosome content. Activation of mitogen activated protein kinase (MAPK) (extracellular signal-regulated kinase 1/2), p53 content and serine-15 phosphorylation of p53 were measured by immunoblot. Electrophoretic mobility shift assay of p53 binding to DNA, and measurement of p21 and glyceraldehyde-3-phosphate dehydrogenase messenger RNA were also done. RESULTS: Resveratrol induced apoptosis in DU 145 cells. The stilbene activated MAPK and caused increased abundance of p53 and serine-15 phosphorylated p53. Resveratrol induced serine-15 phosphorylation of p53 was blocked by PD 98059 (Calbiochem), a MAPK kinase inhibitor, implicating MAPK activation in the phosphorylation of p53. PD 98059 also inhibited resveratrol induced apoptosis. These results suggest that apoptosis induction by resveratrol in DU 145 cells requires serine-15 phosphorylation of p53 by MAPK. Inhibition of MAPK dependent serine-15 phosphorylation resulted in reduced p53 binding to a p53 specific oligonucleotide on electrophoretic mobility shift assay. Pifithrin-alpha (Calbiochem), a p53 inhibitor, blocked resveratrol induced serine-15 phosphorylation of p53 and p53 binding to DNA. Resveratrol caused a p53 stimulated increase in p21 messenger RNA. Transfection of additional wild-type p53 into DU 145 cells induced apoptosis, which was further enhanced by resveratrol treatment. CONCLUSIONS: Resveratrol causes apoptosis in DU 145 prostate cancer cells. This action depends on the activation of MAPK, increase in cellular p53 content, serine-15 phosphorylation of p53 and increased p53 binding to DNA.

Antineoplastic Agents, Phytogenic↗
PubMed2004

[Efficacy of imatinib mesylate, a specific inhibitor of BCR/ABL tyrosine kinase, on chronic myeloid leukemia in blast phase].

BACKGROUND & OBJECTIVE: Chronic myeloid leukemia (CML) in blast phase is refractory with a poor prognosis. This study was to evaluate efficacy of imatinib mesylate, a specific inhibitor of BCR/ABL tyrosine kinase, on CML in blast phase. METHODS: Nineteen patients with CML in blast phase (imatinib treatment group) received induction of cytarabine-based standard chemotherapy for 2 cycles, and 400 mg/d of imatinib mesylate for 4 weeks. Patients with no remission received 600 mg/d of imatinib mesylate for another 8 weeks. Treatment of 600 mg/d of imatinib mesylate was maintained if it showed effects after 8 weeks, otherwise it would be stopped. Twenty-two patients with CML in blast phase (historical control group) received inducement of cytarabine-based chemotherapy for 2 cycles, and other regimens of consolidation or continuous induction. RESULTS: Sixteen patients of imatinib treatment group achieved no hematologic remission after induction. After treated with imatinib mesylate, 6 of 16 (38%) achieved hematologic complete remission (CHR), and major cytogenetic response; 2 of 16(13%) achieved hematologic partial remission (PHR); 1 of 16 (6%) returned to chronic phase with minor cytogenetic response. Total hematologic response rate of imatinib treatment group was 57%; 1-year survival rate was 38% (6/16). Eighteen patients of historical control group achieved no hematologic remission after inducement. After treated with other regimens, 2 (11%) achieved CHR, and 1 (6%) achieved PHR. Total hematologic response rate of historical control group was 17%; 1-year survival rate was 6%(1/18), significantly lower than that of imatinib treatment group (P< 0.05). CONCLUSIONS: Imatinib mesylate may have anti-leukemic activity, and prolong survival time of patients with CML in blast phase. But problems of tumor relapse, and drug resistance are still present.

Adolescent↗
PubMed2005

[Killing effect of 131I-Herceptin on breast cancer cell lines in vitro].

OBJECTIVE: To study the specific killing effect of (131)I-labeled Herceptin on breast cancer cell lines positive for Her-2 expression. METHODS: Anti-Her-2 monoclonal antibody Herceptin was labeled with (131)I by means of IODO-GEN, and the killing effects of Herceptin on SK-BR-3, MCF-7 and A549 cell lines expressing Her-2 were evaluated with MTT assay. RESULTS: (131)I-Herceptin had immunoactivity had to that of Herceptin but possessed stronger killing effects on the cell lines expressing Her-2 than Herceptin and (131)I used alone (P<0.05). Its killing effect on cell lines negative or only weakly positive for Her-2 expression was similar to that of (131)I and Herceptin. CONCLUSION: (131)I-Herceptin can specifically kill Her-2-positive cancer cells in vitro.

Antibodies, Monoclonal↗
PubMed2002

An overview of the pharmacology and pharmacokinetics of the newer generation aromatase inhibitors anastrozole, letrozole, and exemestane.

BACKGROUND: The newer generation, nonsteroidal aromatase inhibitors (AIs) anastrozole and letrozole have shown superior efficacy compared with tamoxifen as first-line treatments and compared with megestrol acetate as second-line therapy in postmenopausal women with advanced breast carcinoma. In an open-label, Phase II trial, it was reported that exemestane showed numerical superiority compared with tamoxifen for objective response and clinical benefit. Because these agents ultimately may be administered for periods of up to 5 years in the adjuvant setting, it is of increasing importance to assess their tolerability and pharmacologic profiles. METHODS: In the absence of data from direct clinical comparisons, the published literature was reviewed for the clinical pharmacology, pharmacokinetic characteristics, and selectivity profiles of anastrozole, letrozole, and exemestane. RESULTS: At clinically administered doses, the plasma half-lives of anastrozole (1 mg once daily), letrozole (2.5 mg once daily), and exemestane (25 mg once daily) were 41-48 hours, 2-4 days, and 27 hours, respectively. The time to steady-state plasma levels was 7 days for both anastrozole and exemestane and 60 days for letrozole. Androgenic side effects have been reported only with exemestane. Anastrozole treatment had no impact on plasma lipid levels, whereas both letrozole and exemestane had an unfavorable effect on plasma lipid levels. In indirect comparisons, anastrozole showed the highest degree of selectivity compared with letrozole and exemestane in terms of a lack of effect on adrenosteroidogenesis. CONCLUSIONS: All three AIs demonstrated clinical efficacy over preexisting treatments. However, there were differences in terms of pharmacokinetics and effects on lipid levels and adrenosteroidogenesis. The long-term clinical significance of these differences remains to be elucidated.

Anastrozole↗
PubMed1999

Treatment of hepatitis caused by cytomegalovirus with allitridin injection--an experimental study.

To demonstrate the anti-cytomegalovirus (CMV) activity of allitridin injection (AI), an active anti-infection component of garlic, the in vitro effects of AI on human CMV (HCMV) AD169 and 7 newly isolated strains from patients and its in vivo effect on mice of murine CMV (MCMV) hepatitis were assessed. It was found that plaque reduction rate reached 63.5% after infected cells were treated with cell maximal tolerable concentration (7.5 micrograms/ml) of AI. Meanwhile, flow cytometric analysis for effect of AI on expression of HCMV immediate-early antigen (IEA) showed that IEA inhibition rate of 7 isolated strains was in the range from 43.3% to 66.7%, with a mean of 58.4%, similar to that of AD169 strain (60.5%). On the other hand, in vivo anti-CMV activity of AI was evaluated in terms of liver pathological changes, liver function and viral replication. Six model mice with MCMV hepatitis received the treatment of AI for 2 weeks. The severity of liver damage, levels of sALT and MCMV IE genes expression in liver tissues in the treated mice were significantly lower than those of the corresponding untreated controls. Our results showed that AI had an obvious anti-CMV activity both in vitro and in vivo.

Allyl Compounds↗
PubMed2004

High-density lipoproteins: multifunctional vanguards of the cardiovascular system.

The plasma level of high-density lipoprotein (HDL)-cholesterol is inversely correlated with coronary artery disease, the leading cause of death worldwide. HDL particles are thought to mediate the uptake of peripheral cholesterol and, through exchange of core lipids with other lipoproteins or selective uptake by specific receptors, return this cholesterol to the liver for bile acid secretion or hormone synthesis in steroidogenic tissues. HDL particles also act on vascular processes by modulating vasomotor function, thrombosis, cell-adhesion molecule expression, platelet function, nitric oxide release, endothelial cell apoptosis and proliferation. Many of these effects involve signal transduction pathways and gene transcription. Several genetic disorders of HDLs have been characterized at the molecular level. The study of naturally occurring mutations has considerably enhanced understanding of the role of HDL particles. Some mutations causing HDL deficiency are associated with premature coronary artery disease, while others, paradoxically, may be associated with longevity. Modulation of HDL metabolism for therapeutic purposes must take into account, not only the cholesterol content of a particle but its lipid (especially phospholipid) composition, apolipoprotein content, size and charge. Current therapeutic strategies include the use of peroxisome proliferating activator receptor-alpha agonists (fibrates) that increase apolipoprotein AI production and increase lipoprotein lipase activity, statins that have a small effect on HDL-cholesterol but markedly reduce low-density lipoprotein-cholesterol, the cholesterol/HDL-cholesterol ratio and niacin that increases HDL-cholesterol. Potential therapeutic targets include inhibition of cholesteryl ester transfer protein, modulating the ATP-binding cassette A1 transporter, and decreasing HDL uptake by scavenger receptor-B1. Novel therapies include injection of purified apolipoprotien AI and short peptides taken orally, mimicking some of the biological effects of apolipoprotein AI.

Cardiovascular System↗
PubMed2001

Abnormal ACTH-stimulation test in a patient with AIDS: adrenal insufficiency or toxoplasmosis?

We here report a 32-year old homosexual man with AIDS who had an abnormal ACTH stimulation test while taking megestrol actetate (megace). On further evaluation, he was found to have recurrent Non-Hodgkin lymphoma (spleen) and intracranial toxoplasmosis, perhaps imitating or aggravating symptoms suggestive of adrenal insufficiency (AI). We diagnosed secondary AI due to megace treatment and tapered this medication under simultaneous hydrocortisone replacement therapy. After the patient's intracranial toxoplasmosis had been treated with intravenous bactrim, his symptoms disappeared. We conclude that patients with AIDS on megace therapy should receive special attention in regards to the potential development of AI, especially in stress situations such as infections or pain.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Could exemestane affect insulin-like growth factors, interleukin 6 and bone metabolism in postmenopausal advanced breast cancer patients after failure on aminoglutethimide, anastrozole or letrozole?

Postmenopausal hormone-sensitive breast cancer is currently treated with either antioestrogens or aromatase inhibitors (AIs), due to the clinical efficacy and safety of these drugs. Today's challenge is the sequential use of AIs with different structure and no cross-resistance to improve the therapeutic outcome. The present study describes the biological action of the steroidal structure (SS)-AI exemestane (EXE), in patients progressing on aminoglutethimide (AG) or other non-steroidal structure (NSS)-AIs (letrozole or anastrozole). Thirteen patients were evaluated for serum insulin-like growth factor (IGF) components [total IGF-1, IGF-2 and IGF binding protein (IGFBP)-3], interleukin (IL)-6 system [IL-6 and soluble IL-6 receptor (sIL-6-R)] and bone metabolism markers [bone gla protein/osteocalcin (BGP), bone-specific isoform of alkaline phosphatase (BAP) and carboxy-telopeptide of type I procollagen (ICTP)]. IGF system components show a trend to increase both in patients progressing on AG and in patients progressing on other NSS-AIs. Such an increase depends on the wash-out length from the previous treatment and is strictly linked to the circulating oestrogen levels. Serum IL-6 and sIL-6-R are mainly related to the patients' clinical outcome. Bone formation (BGP and BAP) and bone resorption (ICTP) markers seem to be at equilibrium with oestrogen levels when starting EXE and do not appear to be uncoupled over treatment. The observed variations seem to be mainly linked to the circulating oestrogen levels rather than directly to the way of action of the AI employed.

Aged↗