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At least 253 records · Page 14Linked to original sources
PubMed2006

[A controlled clinical trial of long course chemotherapy regimens containing rifabutin in the treatment of multi-drug resistant pulmonary tuberculosis].

OBJECTIVE: To evaluate the curative effect and safety of a long course regimen containing Chinese-made rifabutin as compared to the regimen containing rifapentine in the treatment of multi-drug resistant pulmonary tuberculosis. METHOD: During 18 month treatment, 130 patients with multi-drug resistant pulmonary tuberculosis were divided into a treatment group (rifabutin, pasiniazide, levofloxacin, ethambutol, ethionamide, amikacin for 3 months, rifabutin, pasiniazide, levofloxacin, ethambutol, ethionamide for 6 months, rifabutin, pasiniazide, levofloxacin, ethambutol for 9 months), and a control group (rifapentine, pasiniazide, levofloxacin, ethambutol, ethionamide, amikacin for 3 months, rifabutin, pasiniazide, levofloxacin, ethambutol, ethionamide for 6 months, rifabutin, pasiniazide, levofloxacin, ethambutol for 9 months) with proportion 1:1 random, and parallel compared method. RESULTS: After intensive phase, the sputum negative conversion rates (smear negative, culture negative) of the treatment group and the control group were 41.54% (27/65) and 35.94% (23/65), chi(2) = 2.42, P > 0.05, respectively. The remarkable effective rates in chest X-ray of the two groups were all 10.77% (7/65), chi(2) = 0.01, P > 0.05, and the effective rates were 67.69% (44/65) and 56.92% (37/65), chi(2) = 1.44, P > 0.05, respectively. At the end of the treatment, the sputum negative conversion rate (smear negative, culture negative) of the treatment group was 75.0% (48/65), and of the control group was 65.08% (41/65), chi(2) = 1.88, P > 0.05. The remarkable effective rates in chest X-ray of the two groups were 46.15% (30/65) and 44.62% (29/65), chi(2) = 0.02, P > 0.05, and the effective rates were 76.92% (50/65) and 73.85% (48/65), chi(2) = 0.19, P > 0.05, respectively. The cavity closure rates were 23.64% (13/55) and 33.33% (17/51), chi(2) = 0.00, P > 0.05, respectively. CONCLUSION: Regimens containing rifabutin or rifapentine. are very effective in sputum negative conversion rate, lesion absorption and cavity closing for the treatment of multi-drug resistant pulmonary tuberculosis, with good safety and tolerance.

Adult↗
PubMed1990

[Antibiotics and anti-inflammatory agents: drug interactions].

Antibiotics (AB) are sometimes used in patients taking anti-inflammatory drugs (AID) (steroidal and non steroidal anti-inflammatory drugs). At the present time, the usefulness of AID in bacterial infections has been established in a limited number of clinical situations. AID are able to modify the kinetics of AB through different mechanisms which are illustrated by results obtained with cephalosporins and phenylbutazone or diclofenac. In some conditions, these modifications might have consequences on in vivo effect of AB. Conversely, some AB are able to alter metabolism and/or kinetics of some steroids. Interactions of AI on AB toxicity have also been investigated on kidney and central nervous system. AB/AI kinetic interactions have to be investigated for a better understanding of the mechanisms through which AI improve the evolution of an infectious process.

Animals↗
PubMed2003

Antiatherothrombotic effects of nicotinic acid.

Cardiovascular event reduction in hypercholesterolemic subjects appropriately emphasizes the prominent role of statin therapy; however, niacin (nicotinic acid) is also an effective lipid-altering agent that prevents atherosclerosis and reduces cardiovascular events. Niacin has multifarious lipoprotein and anti-atherothrombosis effects that improve endothelial function, reduce inflammation, increase plaque stability, and diminish thrombosis. Niacin reduces the atherogenicity of low-density lipoprotein (LDL) by changing the distribution of small LDL to large LDL subclass, and the susceptibility of LDL to oxidative modification. It is the most effective agent for increasing high-density lipoprotein cholesterol. Moreover, it favorably alters high-density lipoprotein composition, increasing apolipoprotein AI relative to apolipoprotein AII. Niacin reduces blood viscosity through a variety of mechanisms, thus improving blood flow and perfusion through stenotic segments of the vasculature. Finally, niacin has cardioprotective effects that may limit ischemia-reperfusion injury. By preserving glycolysis during periods of ischemia and improving subendocardial blood flow during reperfusion, niacin can improve the functional recovery of the myocardium.

Cholesterol, HDL↗
PubMed2005

Fulvestrant, a new treatment option for advanced breast cancer: tolerability versus existing agents.

Owing to its favourable tolerability profile versus cytotoxic chemotherapy, endocrine therapy is the treatment of choice for postmenopausal women with hormone receptor-positive advanced breast cancer (ABC). However, tolerability concerns associated with some endocrine treatments and the potential for cross-resistance has helped to drive the need for new, effective and better-tolerated agents. Fulvestrant is a new type of oestrogen receptor antagonist with no agonist effects. In phase III trials, fulvestrant has been shown to be at least as effective as the third-generation aromatase inhibitor (AI) anastrozole in the treatment of postmenopausal women with ABC progressing on prior tamoxifen therapy. Fulvestrant is administered as a once-monthly 250 mg intramuscular injection into the gluteus muscle. Here we review the tolerability of fulvestrant in the treatment of postmenopausal women with hormone-sensitive ABC and compare it with that of the four most frequently prescribed endocrine treatments for advanced disease (tamoxifen, anastrozole, letrozole and exemestane). Compared with these agents, fulvestrant is well tolerated and is associated with a lower incidence of joint disorders compared with the non-steroidal AIs and none of the potential androgenic side-effects that are sometimes seen with steroidal AIs. It is also associated with hot flushes compared with tamoxifen. Fulvestrant therefore provides clinicians and patients with a useful, well-tolerated option for the treatment of hormone-sensitive ABC. Integration of such agents into the endocrine treatment sequence may extend the opportunity for using well-tolerated therapies before chemotherapy needs to be considered and thus may improve quality of life for patients with ABC. The overall safety profiles of newer agents such as fulvestrant will become increasingly clear with their ongoing use.

Anastrozole↗
PubMed2006

Controlled release of avermectin from porous hollow silica nanoparticles: influence of shell thickness on loading efficiency, UV-shielding property and release.

Preparation and characterization of porous hollow silica nanoparticles (PHSNs), with various shell thicknesses in the range of 5-45 nm and a pore diameter of about 4-5 nm, were investigated. PHSNs were fabricated via a sol-gel route with two different structure-directing templates and their shell thickness could be controlled by adjusting the reactant ratio of Na2SiO3.9H2O/CaCO3. The produced PHSNs were applied as controlled pesticide release carriers to study the effects of the shell thickness on the loading efficiency for avermectin, the UV-shielding property for the loaded avermectin and the controlled release of the loaded avermectin from the carriers. It was found that the amount of loaded avermectin decreases with the increase of shell thickness, while the UV-shielding property of PHSNs for avermectin is improved as the shell gets thicker. In addition, the shell thickness has a significant impact on avermectin release. Increasing the shell thickness in the range of 5-45 nm leads to a more sustained release by decreasing the release rate of the pesticide from PHSNs, showing that the shell thickness is one of the main controlling factors for the active agent release from such systems.

Delayed-Action Preparations↗
PubMed2006

Incidence and management of side effects associated with aromatase inhibitors in the adjuvant treatment of breast cancer in postmenopausal women.

OBJECTIVE: Third-generation aromatase inhibitors (AIs) are effective and generally well-tolerated as adjuvant therapy. These AIs are now being introduced for the adjuvant treatment of postmenopausal patients with estrogen-receptor-positive early-stage breast cancer. However, questions remain about their long-term safety. This paper summarizes the adverse events reported in third-generation AI trials and comments on the appropriate management of these drug-induced adverse events in patients. METHODS: Papers relating to anastrozole, exemestane, and letrozole were identified through Medline searches, and proceedings of recent oncology meetings were also reviewed to capture relevant emerging data. RESULTS: The most commonly reported adverse events associated with adjuvant AI therapy include hot flushes and musculoskeletal complaints/arthralgia. The incidence of endometrial cancer and thromboembolic events is significantly lower with an AI than with tamoxifen. However, there is a small but significant increase in the risk of osteoporosis and fractures with AI therapy. A potential negative effect on the cardiovascular system, specifically on lipid metabolism, has not been conclusively demonstrated. No significant differences in overall quality of life were observed in studies comparing AIs with tamoxifen or placebo. CONCLUSION: AIs alone and sequenced after tamoxifen are an appropriate option for adjuvant endocrine therapy for most postmenopausal patients with hormone-responsive breast cancer. The incidence of some side effects such as endometrial cancer, stroke, or pulmonary embolism associated with tamoxifen is decreased. Monitoring and management of bone loss associated with AI treatment are essential and are being addressed in ongoing trials. Further studies with longer follow-up are required to clarify the effects of AIs on lipid metabolism and cardiovascular health.

Antineoplastic Agents, Hormonal↗
PubMed2003

[Bio-panning of antagonistic peptides against HAb18G/CD147 and their function of anti-hepatoma invasion].

OBJECTIVE: To screen out the HAb18G/CD147 binding peptides and find out an antagonist against hepatoma invasion. METHODS: HAb18G/CD147 was purified by affinity chromatographic method and the antigen binding peptides acquired by bio-panning a phage-displayed 12-peptide library. After obtaining the sequence of the selected phage-displayed peptides, all the 9 peptides were synthesized by solid-phase method and identified by mass spectrograph. The peptides' anti-metastatic function was tested by Boyden Chamber assay. RESULTS: The purified HAb18G/CD147, identified by Western blot (molecular weight about 65 kd) could be used to bio-pan the phage-displayed peptide library. After 3 rounds of bio-panning, 9 positive phage clones were selected and sequenced. The synthesized peptides had uneven inhibitory activities and three of them were able to markedly inhibit the hepatoma cell invasion (P < 0.01). The most effective peptide decreased by 90.1% of hepatoma cells migrating through the Boyden Chamber membrane as compared with the control. CONCLUSION: Bio-panning the phage-displayed peptide library can be used successfully to screen out the antigen binding peptides. Hepatoma metastatic potential can be inhibited by peptide antagonist which could be a good foundation of developing peptide therapeutic agent against hepatoma metastasis.

Animals↗
PubMed2006

Selection of optimal adjuvant endocrine therapy for early-stage breast cancer.

Oophorectomy was found to cause regression of advanced breast cancer toward the end of the 19th century. Decades later, the discovery that estrogen plays a central role in this process eventually led to two important consequences: first, different modalities were developed to suppress or antagonize estrogen; and second, the ability to detect estrogen receptor in breast cancer tissue became a predictor of response to treatment--probably the best marker for response among all solid tumors. Tamoxifen, which works by competitively antagonizing hormonal receptors in breast cancer cells, has been for the past three decades the standard of care for adjuvant therapy for any woman with hormone receptor-positive early breast cancer, regardless of nodal status or menopausal setting. But as we strive to improve the utility of antagonizing or suppressing estrogen, new modalities are being developed. In the premenopausal setting, the advent of gonadotropin hormone-releasing hormone (also known as luteinizing hormone-releasing hormone) analogues has allowed for medical and reversible suppression of ovarian function. This method has already been proven as effective as chemotherapy in preventing recurrence, and ongoing trials are aiming to better define its role in the adjuvant setting. In the postmenopausal setting, aromatase inhibitors (AIs) have revolutionized the adjuvant treatment of hormone-responsive cancers of all stages. The current standard of care has come to include AIs, as an alternative, in sequence, of after 5 years of tamoxifen. Ongoing research continues to develop agents to overcome hormonal therapy resistance.

Adult↗
PubMed1999

Management of gingival overgrowth associated with generalized enamel defects in a child.

Gingival overgrowth is usually associated with systemic conditions or treatment (e.g. blood dyscrasias, anti-epileptic or immunosuppressive agents). A child is presented, who had enlarged gingiva associated with a generalized enamel defect (amelogenesis imperfecta (AI), hypoplastic type) and document the periodontal and restorative management of this case.

Amelogenesis Imperfecta↗
PubMedDate not supplied

Possible pathomechanism of autoimmune hepatitis.

The hepatotropic viruses, measles, and herpesviruses as well as different drugs were repeatedly shown to act presumably as a trigger in patients with autoimmune hepatitis (AI-H). On the other hand, it is known that viral infections stimulate interferon production, which inactivates the cytochrome P-450 enzymes involved in the metabolism of several endogenous substances and exogenous environmental agents. Moreover, it was reported that several cytokines, including interferons, as well as transforming growth factor beta1 and human hepatocyte growth factor, which are abundantly produced and released in the body during infections, also downregulated expression of major cytochrome P-450 and/or other biotransformation enzymes. It seems that all these factors, in addition to individual immune response and the nature and amount of the neoantigen(s) produced, impair the equilibrium of bioactivation and detoxication pathways, thus leading to the development of AI-H in a genetically predisposed person continually exposed to harmful environmental factor(s). Possible increased/decreased density of lysine residues at position D-related human leukocyte antigen locus (DR)beta71 of the antigen-binding groove may affect the eventual steroid-sparing effect of this critical amino acid at the cellular level. In addition, some food additives, such as monosodium glutamate (MSG) and/or aspartame regularly consumed in excessive amounts, may eventually disturb the delicate balance between a positively charged amino acid residue at position DRbeta71 (lysine or arginine) and a negatively charged amino acid residue at position P4 on the antigenic peptide (glutamic acid or aspartic acid). This may favor formation of a salt bridge between these amino acid residues within the hypervariable region 3 on the alpha-helix of the DRbeta polypeptide and facilitate autoantigen presentation and CD4 T-helper cell activation. MSG and aspartate may also depress serum concentrations of growth hormone, which downregulate the activity of several cytochrome P-450 hepatic and other drug-metabolizing enzymes, thus increasing sensitivity to some environmental agents and possibly influencing efficacy of treatment regimens and final outcome of patients with type 1 AI-H.

Female↗
PubMed2003

Origin and characteristics of adverse events in aromatase inhibition therapy for breast cancer.

Estrogen is critical in the progression and probably also in the initiation of breast tumors. Two classes of pharmacologic agents currently used in the treatment of estrogen receptor-positive breast tumors are the selective estrogen receptor modulators such as tamoxifen that block the interaction of estrogen with its cognate receptor, and the aromatase inhibitors (AIs) that block the final enzymatic step in the estrogen biosynthetic pathway. Recent data from first-line phase III trials in postmenopausal patients with hormone receptor-positive or -unknown metastatic breast cancer suggest that AIs are at least equivalent to or more effective than tamoxifen in this setting. As a result AIs are being evaluated in the adjuvant setting and may eventually displace tamoxifen as the endocrine therapy of choice for postmenopausal patients with breast cancer. Among the side effects of therapy that were observed in metastatic trials, AIs have shown less vascular and uterine adverse events than tamoxifen. Some concern exists, however, regarding their effect on lipid metabolism and bone turnover. To be acceptable for adjuvant treatment, AIs will have to show not only an advantage in efficacy, but also that any concerns from potential side effects may be managed appropriately. This article reviews the safety profile of AIs, discussing events related to their chemical structure, their specificity, and the effects of estrogen deprivation on target organs.

Antineoplastic Agents, Hormonal↗
PubMed2006

Retention of paclitaxel in cancer cells for 1 week in vivo and in vitro.

PURPOSE: Clinically, the administration of paclitaxel for ovarian cancer on a dose-dense weekly schedule, rather than the conventional every-3-week schedule, might demonstrate greater tumor-cell death. Here, we investigate the pharmacokinetics and the pharmacodynamics of weekly paclitaxel in cancer cells in vivo and in vitro. EXPERIMENTAL DESIGN: Paclitaxel concentrations were measured by HPLC, and apoptotic cells were detected by TUNEL assay in paclitaxel-pretreated cervical cancer cells treated with paclitaxel (10 ng/ml) and in the tissues of cervical cancer patients treated with weekly paclitaxel (60 mg/m2/week). Polymerized tubulin was detected with a tubulin polymerization assay, and the BrdU cell proliferation assay was used to assess the effect of paclitaxel. RESULTS: Paclitaxel remained in the cancer tissues of six patients for 6 days after the last medication. In vitro, paclitaxel was retained in all cell lines for 24 h after its removal from the medium, and paclitaxel was still detectable in CaSki cells on day 7. Simultaneous treatment with depolymerizing drugs inhibited the retention of paclitaxel in cells and paclitaxel-induced polymerization of tubulin. After paclitaxel treatment, apoptotic cells were detected in cancer tissues and CaSki cells for 1 week. Under high magnification, apoptotic cells on day 7 after paclitaxel treatment showed multinucleation. CONCLUSIONS: Paclitaxel is unusual in that it accumulates especially in cancer cells and induces apoptosis for 1 week in vivo and in vitro. On the other hand, paclitaxel could not be detected in cancer tissues after 2 weeks. The administration of paclitaxel on a weekly schedule, rather than the standard every-3-week schedule, might produce greater tumor-cell death.

Antineoplastic Agents, Phytogenic↗
PubMed2003

Apoptosis in the normal and inflamed airway epithelium: role of zinc in epithelial protection and procaspase-3 regulation.

The epithelium lining the airways is a physical barrier as well as a regulator of physiological and pathological events in the respiratory system. Damage to the epithelium by oxidants released from inflammatory cells is a critical factor in the pathogenesis of airway inflammatory diseases such as bronchial asthma. In these diseases, excessive apoptosis may be a likely mechanism responsible for damage to, and sloughing, of airway epithelial cells. Factors that increase the airway epithelium's resilience to apoptosis are likely to lessen the severity of this disease. One such factor is the dietary metal zinc. A special role for labile intracellular pools of zinc as anti-apoptotic agents in the regulation of the caspases, has emerged over the past two decades. This review focuses on caspase-inhibitory functions of zinc in airway epithelial cells, apparent abnormalities of zinc homeostasis in asthmatics and studies from the authors' laboratory which showed that zinc was strategically localized in the apical cytoplasm of airway epithelium to control caspase-3 activated apoptosis. These findings are discussed in the context of recent data from a murine model of allergic asthma, showing that loss of airway epithelial zinc was accompanied by changes in levels of both procaspase-3 and active caspase-3 and that nutritional zinc deprivation further increased airway epithelial apoptosis. We hypothesize that zinc has a protective role for the airway epithelium against oxyradicals and other noxious agents, with important implications for asthma and other inflammatory diseases where the epithelial barrier is vulnerable and compromised.

Animals↗
PubMed2002

Antiproliferative and cytotoxic effect of a novel organotin compound on mammalian cells both in vitro and in vivo.

Organotin compounds are organometallic compounds showing various toxicological properties. Several organotin compounds also showed an antineoplastic effect. However, their relative mutagenic potential is not well established. In this study Et(2)SnCl(2).L [L=N-(2-pyridylmethylene)-4-toluidine] (OTC) has been subjected to investigation for its cytotoxic effect in mouse bone marrow cells (BMCs) and human peripheral blood lymphocyte cells (HPBLs). The Sn [bond] N bond in OTC is 2.46A which is greater than 2.39A and therefore, a better formation of tin-DNA complex can be expected. The present data indicate that OTC induced significant delay in cell kinetics and sister chromatid exchanges (SCEs) in both BMCs and HPBLs, whereas, induction of chromosome aberrations was found only in HPBLs. The presence of buthionine sulfoximine (BSO) modulated cellular sensitivity towards OTC in both cell systems. It may be inferred that the OTC could bind on DNA more easily owing to its structural advantage and this may explain the induction of DNA damage and the delay in cell proliferation. Since the cytotoxic effect of OTC is more in glutathione depleted cells, the concentration of OTC may be reduced to get an antitumour effect in GSH-depleted cells and thus minimizes its toxic side effect.

Animals↗