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C M Martinez

Publications and source records attributed to C M Martinez.

11 recordsLinked to original sources
PubMed2006

Characterization of a murine model of intranasal infection suitable for testing vaccines against C. abortus.

Mouse models have been widely used to test candidate vaccines against Chlamydophila abortus infection in mice. Although the induction of a systemic infection by endogenous or intraperitoneal inoculation is a useful tool for understanding the immune mechanism involved in the protection conferred by the vaccination, a different approach is necessary to understand other factors of the infection, such as mucosal immunity or the colonization of target organs. To test whether C. abortus intranasal model of infection in mice is a useful tool for testing vaccines in a first group of experiments mice, were infected intranasally with C. abortus to characterize the model of infection. When this model was used to test vaccines, two inactivated experimental vaccines, one of them adjuvated with QS-21 and another with aluminium hydroxide, and a live attenuated vaccine (strain 1B) were used. Non-vaccinated control mice died within the first 8 days, after displaying substantial loss of weight. Histologically, the mice showed lobar fibrinopurulent bronchointerstitial pneumonia. Prior immunization with QS-21 adjuvated vaccine or 1B vaccine presented mortality and the recipients showed a greater number of T cells in the lesions, especially CD8(+) T cells, than the control mice and mice immunized with vaccine adjuvated with aluminium hydroxide. The results confirm that the C. abortus intranasal model of infection in mice is a useful tool for testing vaccines.

Abortion, Veterinary↗
PubMed1998

Sordarins: in vitro activities of new antifungal derivatives against pathogenic yeasts, Pneumocystis carinii, and filamentous fungi.

GM 193663, GM 211676, GM 222712, and GM 237354 are new semisynthetic derivatives of the sordarin class. The in vitro antifungal activities of GM 193663, GM 211676, GM 222712, and GM 237354 against 111 clinical yeast isolates of Candida albicans, Candida kefyr, Candida glabrata, Candida parapsilosis, Candida krusei, and Cryptococcus neoformans were compared. The in vitro activities of some of these compounds against Pneumocystis carinii, 20 isolates each of Aspergillus fumigatus and Aspergillus flavus, and 30 isolates of emerging less-common mold pathogens and dermatophytes were also compared. The MICs of GM 193663, GM 211676, GM 222712, and GM 237354 at which 90% of the isolates were inhibited (MIC90s) were 0.03, 0.03, 0.004, and 0.015 microg/ml, respectively, for C. albicans, including strains with decreased susceptibility to fluconazole; 0.5, 0.5, 0.06, and 0.12 microg/ml, respectively, for C. tropicalis; and 0.004, 0.015, 0.008, and 0.03 microg/ml, respectively, for C. kefyr. GM 222712 and GM 237354 were the most active compounds against C. glabrata, C. parapsilosis, and Cryptococcus neoformans. Against C. glabrata and C. parapsilosis, the MIC90s of GM 222712 and GM 237354 were 0.5 and 4 microg/ml and 1 and 16 microg/ml, respectively. The MIC90s of GM 222712 and GM 237354 against Cryptococcus neoformans were 0.5 and 0.25 microg/ml, respectively. GM 193663, GM 211676, GM 222712, and GM 237354 were extremely active against P. carinii. The efficacies of sordarin derivatives against this organism were determined by measuring the inhibition of the uptake and incorporation of radiolabelled methionine into newly synthesized proteins. All compounds tested showed 50% inhibitory concentrations of <0.008 microg/ml. Against A. flavus and A. fumigatus, the MIC90s of GM 222712 and GM 237354 were 1 and 32 microg/ml and 32 and >64 microg/ml, respectively. In addition, GM 237354 was tested against the most important emerging fungal pathogens which affect immunocompromised patients. Cladosporium carrioni, Pseudallescheria boydii, and the yeast-like fungi Blastoschizomyces capitatus and Geotrichum clavatum were the most susceptible of the fungi to GM 237354, with MICs ranging from </=0.25 to 2 microg/ml. The MICs of GM 237354 against Trichosporon beigelii and the zygomycetes Absidia corymbifera, Cunninghamella bertholletiae, and Rhizopus arrhizus ranged from </=0.25 to 8 microg/ml. Against dermatophytes, GM 237354 MICs were >/=2 microg/ml. In summary, we concluded that some sordarin derivatives, such as GM 222712 and GM 237354, showed excellent in vitro activities against a wide range of pathogenic fungi, including Candida spp., Cryptococcus neoformans, P. carinii, and some filamentous fungi and emerging invasive fungal pathogens.

Adenosine Triphosphate↗
PubMed1997

Cidofovir use in acyclovir-resistant herpes infection.

Herpes infections continue to be prevalent, especially in immunocompromised patients. Some of these patients will develop resistant HSV infections. Therefore, it is important to explore new treatment options. Animal studies have shown cidofovir to be effective in the treatment and prevention of HSV infections. Human data are limited, with only one randomized, double-blind, placebo-controlled trial performed to date. The results from this study look promising; however, due to the small sample size, a larger clinical trial is warranted. The human data available as case reports are suboptimal in the quality of reporting time frames for resolution of lesions/symptoms and outcomes of therapy. Another problem with the case report data is that the TK status of the herpes simplex isolates was not reported. This would have helped substantiate the acyclovir resistance seen in these patients. It was evident in these case reports that acyclovir resistance can be overcome, as acyclovir-resistant strains became sensitive following cidofovir therapy. This may be because TK(+) viruses have been shown to establish latency more readily than do TK(-) viruses. This pattern suggests that alternating between acyclovir and cidofovir therapies may provide a strategy to manage the emergence of alternatively acyclovir-sensitive and -resistant infections. At present, only the intravenous formulation of cidofovir is commercially available. Advantages of the intravenous formulation include weekly dosing and efficacy. Disadvantages are the complexity of administration and the adverse effect profile. The most common adverse effects with this formulation include nephrotoxicity manifested as proteinuria (12%), and increased creatinine (5%) and neutropenia (15%). Administration of probenecid and NaCl 0.9% hydration are used to reduce the incidence and severity of nephrotoxicity in patients who are receiving cidofovir. Probenecid also has toxicities, including nausea, vomiting, headache, fever, and flushing. The topical formulation of cidofovir looks promising for mucocutaneous HSV infection because it is usually undetectable in the blood following topical administration. Therefore, systemic adverse effects should be minimized. A cidofovir gel product (Forvade, Gilead Sciences) is currently being reviewed by the Food and Drug Administration for the treatment of refractory HSV. Ultimately, more controlled clinical studies are necessary to determine whether routine cidofovir use can be justified in patients with acyclovir-resistant HSV infection.

Acyclovir↗
PubMed1990

Comparative study of toxic lead effect on gill and haemoglobin of tilapia fish.

This study was designed to determine the 72-h LC50 of lead for tilapia fish (Oreochromis hornorum), as well as the effect of exposure to sublethal lead concentrations (15, 23, 31, 39 and 47% of the LC50) on gill tissue lysosomal membranes of the fish and thaemoglobin concentration in blood. The LC50 value was found to be 202 mg Pb2+ l-1. Exposure to sublethal lead concentrations for 72 h showed significant increases in the lability of gill lysosomal membranes, measured by the release of acid phosphatase. Changes in membrane lability and in haemoglobin concentration were dependent on the amount of lead used during the exposure. We considered that the membrane lability is an adequate parameter to assay for monitoring lead contamination in water, because it is more sensitive than the haemoglobin concentration in blood.

Acid Phosphatase↗
PubMed1976

Pneumomediastinum following a surgical renal biopsy.

A case of pneumomediastinum, which appeared after a biopsy of the right kidney by minimal lumbotomy, is reported. The anatomicopathological condition of the renal fragment obtained was judged to be focal and segmental hyalinosis. We wish to emphasize the rarity of such a complication, the type of electrocardiographic changes observed, and the rapid and spontaneous recuperation of the patient without further repercussions.

Adult↗
PubMedDate not supplied

The cardiac toxicity of anabolic steroids.

Anabolic steroids are synthetic derivatives of testosterone that were developed as adjunct therapy for a variety of medical conditions. Today they are most commonly used to enhance athletic performance and muscular development. Both illicit and medically indicated anabolic steroid use have been temporally associated with many subsequent defects within each of the body systems. Testosterone is the preferred ligand of the human androgen receptor in the myocardium and directly modulates transcription, translation, and enzyme function. Consequent alterations of cellular pathology and organ physiology are similar to those seen with heart failure and cardiomyopathy. Hypertension, ventricular remodeling, myocardial ischemia, and sudden cardiac death have each been temporally and causally associated with anabolic steroid use in humans. These effects persist long after use has been discontinued and have significant impact on subsequent morbidity and mortality. The mechanisms of cardiac disease as a result of anabolic steroid use are discussed in this review.

Anabolic Agents↗
PubMedDate not supplied

Atrial fibrillation and anabolic steroids.

A young male bodybuilder, consuming large doses of anabolic steroids (AS), presented to the Emergency Department (ED) with symptomatic rapid atrial fibrillation (AF). Echocardiogram revealed significant septal hypokinesis, and posterior and septal wall thickness at the upper limit of normal for highly trained athletes. The atrial fibrillation had not recurred at 10 weeks after discontinuation of AS use. Consumption of these agents in athletes has been associated with hypertension, ischemic heart disease, hypertrophic cardiomyopathy, and sudden death.

Adult↗
PubMedDate not supplied

Use of automated reminders for tuberculin skin test return.

INTRODUCTION: This study assessed the impact of automated telephone reminders on tuberculin skin test returns. METHODS: A total of 701 English-speaking and Spanish-speaking patients of a public health immunization program were randomly assigned to an intervention or a control group. Those in the intervention group received an automated telephone reminder to return for the reading of their skin test. RESULTS: Automated telephone reminders significantly reduced return failures 53% (from 14% to 7%) when the scheduled interval between test administration and reading was three days, but had no impact for a two-day interval. Effectiveness of reminders did not differ significantly by patient age, gender, or language (English versus Spanish). CONCLUSIONS: Results suggest the value of automated reminder calls for intra-appointment intervals as short as three days.

Adolescent↗