Search results for "Aminoglycosides"
showing 10 items of 18 documents
Rapid generation of hydrogen peroxide contributes to the complex cell death induction by the angucycline antibiotic landomycin E
2017
Landomycin E (LE) is an angucycline antibiotic produced by Streptomyces globisporus. Previously, we have shown a broad anticancer activity of LE which is, in contrast to the structurally related and clinically used anthracycline doxorubicin (Dx), only mildly affected by multidrug resistance-mediated drug efflux. In the present study, cellular and molecular mechanisms underlying the anticancer activity of landomycin E towards Jurkat T-cell leukemia cells were dissected focusing on the involvement of radical oxygen species (ROS). LE-induced apoptosis distinctly differed in several aspects from the one induced by Dx. Rapid generation of both extracellular and cell-derived hydrogen peroxide alr…
Perspectives for the Treatment of Brucellosis in the 21st Century: The Ioannina Recommendations
2007
Policy Forum. Competing interests: ER has received research grants from Daiichi, Bayer, and Theravance and has served as a consultant to Pfizer, Theravance, Bayer, Wyeth, Rosetta, and BiondVax. Summary Points Brucellosis remains the commonest anthropozoonosis worldwide, and its treatment remains complex, requiring protracted administration of more than one antibiotic. In November 2006, a consensus meeting aimed at reaching a common specialist statement on the treatment of brucellosis was held in Ioannina, Greece under the auspices of the International Society of Chemotherapy and the Institute of Continuing Medical Education of Ioannina. The author panel suggests that the optimal treatment o…
Final report of the efficacy and safety of gemtuzumab ozogamicin (Mylotarg) in patients with CD33-positive acute myeloid leukemia in first recurrence
2005
BACKGROUND In this study, the authors analyzed the efficacy and safety of gemtuzumab ozogamicin (GO) (Mylotarg®), an antibody-targeted chemotherapy for CD33-positive acute myeloid leukemia (AML). METHODS Patients with CD33-positive AML in first recurrence were entered in 3 open-label, single-arm, Phase II studies. Patients received monotherapy with GO 9 mg/m2 as a 2-hour intravenous infusion in 2 doses separated by 2 weeks. Patients were evaluated for remission, survival, and treatment-emergent adverse events. RESULTS Two hundred seventy-seven patients (median age, 61 yrs) were treated with GO, and 71 patients (26%) achieved remission, which was defined as ≤ 5% blasts in the bone marrow wit…
Salvage therapy with high-dose cytarabine and mitoxantrone in combination with all-trans retinoic acid and gemtuzumab ozogamicin in acute myeloid leu…
2015
Outcome of patients with primary refractory acute myeloid leukemia remains unsatisfactory. We conducted a prospective phase II clinical trial with gemtuzumab ozogamicin (3 mg/m(2) intravenously on day 1), all-trans retinoic acid (45 mg/m(2) orally on days 4-6 and 15 mg/m(2) orally on days 7-28), high-dose cytarabine (3 g/m(2)/12 h intravenously on days 1-3) and mitoxantrone (12 mg/m(2) intravenously on days 2-3) in 93 patients aged 18-60 years refractory to one cycle of induction therapy. Primary end point of the study was response to therapy; secondary end points included evaluation of toxicities, in particular, rate of sinusoidal obstruction syndrome after allogeneic hematopoietic cell tr…
International survey of antibiotic dosing and monitoring in adult intensive care units
2023
Background: In recent years, numerous dosing studies have been conducted to optimize therapeutic antibiotic exposures in patients with serious infections. These studies have led to the inclusion of dose optimization recommendations in international clinical practice guidelines. The last international survey describing dosing, administration and monitoring of commonly prescribed antibiotics for critically ill patients was published in 2015 (ADMIN-ICU 2015). This study aimed to describe the evolution of practice since this time. Methods: A cross-sectional international survey distributed through professional societies and networks was used to obtain information on practices used in the dosing…
Glycoprotein molecules in the walls of Schizosaccharomyces pombe wild-type cells and a morphologically altered mutant resistant to papulacandin B
1990
SUMMARY: Schizosaccharomyces pombe cell walls contain two major glycoprotein species, I and II, with molecular masses of 2 x 106 and 5 x 105 Da respectively, as determined by gel filtration chromatography and PAGE. The ratio of sugar to protein is higher in species I than in species II. Much of the sugar in both glycoproteins (about 85% in wild-type cells) is O-linked to the peptide moiety. The morphological sph1 mutant is resistant to papulacandin B, and its cell wall contains less glycoprotein II (but not less glycoprotein I) than the parental wild-type strain, although glycoprotein II is still synthesized and released into the growth medium. Papulacandin B largely reverses the morphologi…
Isolation and characterization of Saccharomyces cerevisiae mutants resistant to aculeacin A
1991
Aculeacin A is a lipopeptide that inhibits beta-glucan synthesis in yeasts. A number of Saccharomyces cerevisiae mutants resistant to this antibiotic were isolated, and four loci (ACR1, ACR2, ACR3, and ACR4) whose products are involved in the sensitivity to aculeacin A of yeast cells were defined. Mutants containing mutations in the four loci were also resistant to echinocandin B, another member of this lipopeptide family of antibiotics. In contrast, acr1, acr3, and acr4 mutants were resistant to papulacandin B (an antibiotic containing a disaccharide linked to two fatty acid chains that also inhibits beta-glucan synthesis), but acr2 mutants were susceptible to this antibiotic. This result …
Formation of a new cell wall by protoplasts of Candida albicans: effect of papulacandin B, tunicamycin and Nikkomycin.
1987
SUMMARY: Incorporation of polysaccharides into the walls of regenerating protoplasts of Candida albicans was followed in the presence of papulacandin B, tunicamycin and nikkomycin. With the first drug, chitin was incorporated normally whereas incorporation of glucans and mannoproteins was significantly decreased. Tunicamycin decreased incorporation of all wall polymers when added at the beginning of the regeneration process but blocked only mannan and alkali-insoluble glucan incorporation when added after 5 h. Nikkomycin inhibited chitin synthesis, and the walls formed by the protoplasts were enriched in alkali-soluble glucan. Pulse-chase experiments suggested that a precursor-product relat…
A kinetic study on the regeneration ofCandida albicansprotoplasts in the presence of cell wall synthesis inhibitors
1993
Aculeacin A and papulacandin B block cell wall regeneration in Candida albicans protoplasts at an intermediate step in which the protoplasts have not yet synthesized the rigid structure of the cell wall and are therefore still osmotically sensitive. In the presence of the antibiotics, total synthesis of glucan is not significantly lowered with respect to control cells, although most of it appears either in the culture medium or in the regenerating wall as alkali-soluble glucan. Thus, it is proposed that echinocandins (such as aculeacin A) and papulacandins may not inhibit glucan synthesis per se but instead inhibit its incorporation into the supramolecular organization of the cell wall.
Fighting mycobacterial infections by antibiotics, phytochemicals and vaccines.
2011
Buruli ulcer is a neglected disease caused by Mycobacterium ulcerans and represents the world's third most common mycobacterial infection. It produces the polyketide toxins, mycolactones A, B, C and D, which induce apoptosis and necrosis. Clinical symptoms are subcutaneous nodules, papules, plaques and ulcerating oedemae, which can enlarge and destroy nerves and blood vessels and even invade bones by lymphatic or haematogenous spread (osteomyelitis). Patients usually do not suffer from pain or systematic inflammation. Surgery is the treatment of choice, although recurrence is common and wide surgical excisions including healthy tissues result in significant morbidity. Antibiotic therapy wit…