Suceptibilidad in vitro al ajoene de aislados de candida albicans C. parapsolosis y C. krusei: obtenidos de pacientes con onicomicosis y su relación con el tratamiento tópico / Suceptibility in vitro to the ajoene of isolated of candida albicans C. parapsolosis and C. krusei obtained from patient with onycomycosis and their relationship with tropical treatment

Ajoene es un compuesto órganosulfurado, obtenido originalmente de extractos alcohólicos del ajo, y presenta una actividad antimicótica que ha sido ampliamente demostrada. En este trabajo estudiamos la suceptibilidad in vitro al ajoene de levaduras aisladas de pacientes con onicomicosis, siguiendo directrices de NCCLS M27-A con modificaciones (RPMI 2 por ciento G y uso de un hemocitómetro). Se determinaron la CMI y CI de ajoene, fluconazol y terbinafina. Los valores del CMI oscilaron entre (2,34 - 70,2 µM/ml), y la CI entre (0,26 - 7,08 µM/ml), y se relacionaron con la actividad in vivo mostrada por este compuesto. Para ello fueron seleccionados 8 pacientes con diagnóstico clínico y micológico de onicomicosis. Seis recibieron ajoene solución 0,4 por ciento y fluconazol 150 mg/semanales por 4 meses, con controles clínicos y micológicos a los 30, 60 y 90 días. Todos los pacientes tratados con ajoene mostraron después de cuatro meses de tratamiento, una importante mejoría de los síntomas, y siete de los ocho tratados mostraron cura micológica

Estudio de la suceptibilidad in vitro de aislados de microsporum canis al ajoene terbinafina y griseofulvina: utilizando el método de microdilución / Suceptibility in vitro of microsporum canis to ajoene terninafine and griseofulvin: evaluatiom of a microdilution test

Ajoene es un agente seguro y eficaz en el tratamiento de algunas dermatofitosis; ha mostrado su actividad sobre aislados de microsporum canis, prefilándose como una potencial droga para el tratamiento tópico de la tinea capitis; por ello consideramos relevante determinar la suceptibilidad in vitro de seis aislados de microsporum canis, obtenidos de pacientes con dicha patología, a los antifúngicos ajoene, terbinafina y griseofulvina, utilizando procedimientos establecidos por el NCCLS M38-A, con algunas modificaciones. Para el compuesto ajoene los valores de la CIM y CI estuvieron entre 30-204 µM y 1,45-2,96 µM; las CIMs y CI de terbinafina se localizaron entre 10-30 µM y 0,02-0,12 µM para la griseofulvina entre 10-30 µM y 1,08-3,91 µM, respectivamente. M. canis fue suceptible a ajoene de manera dosis-dependiente, pudiendo este compuesto constituir una alternativa eficiente para el tratamiento de la tinea capitis

Sandfly fauna of endemic leishmaniasis foci in Anzoátegui State, Venezuela.

A census of the sandfly fauna was undertaken in 1993-98 in 5 endemic leishmaniasis foci situated at different altitudes in Anzoátegui State, Venezuela. From the 17 species of Lutzomyia identified, we believe that Lu. ovallesi, Lu. panamensis and Lu. gomezi are the probable vectors of cutaneous leishmaniasis, while Lu. evansi might transmit visceral leishmaniasis.

Efficacy of ajoene in the treatment of tinea pedis: a double-blind and comparative study with terbinafine.

Ajoene, an organosulfur compound originally isolated from garlic, has been shown to be effective in short-term treatment of tinea pedis. We compare the safety and effectiveness of twice-daily topical application during 1 week of 0.6% and 1% ajoene and 1% terbinafine in the treatment of tinea pedis. Seventy soldiers from the Venezuelan Armed Forces, with clinical and mycologic diagnosis of tinea pedis, were included in this study. However, only 47 were available for final evaluation. The patients were randomly distributed into 3 treatment groups: 0.6% ajoene, 1% ajoene, and 1% terbinafine. Clinical follow-up shows a rapid decline in the signs and symptoms in all groups. Efficacy of the treatments, measured as mycologic cure, 60 days after the end of the therapy was 72% for 0.6% ajoene, 100% for 1% ajoene, and 94% for 1% terbinafine. This represents the first demonstration of the therapeutic application of an inhibitor of phospholipid biosynthesis in human dermatophytosis.

Ajoene in the topical short-term treatment of tinea cruris and tinea corporis in humans. Randomized comparative study with terbinafine.

Ajoene (CAS 92284-99-6), an organic trisulphur originally isolated from garlic, has an antimycotic activity which has been widely demonstrated both in vitro and in vivo. The objective of this work was to compare the safety and effectiveness of ajoene (0.6%, gel) with terbinafine (CAS 91161-71-6) (1%, cream) for the treatment of tinea corporis and tinea cruris. The patients selected were 60 soldiers with clinical and mycological diagnosis of either dermatophytosis. They were distributed at random in two treatment groups, one treated with ajoene at 0.6% and the other with terbinafine at 1%. All patients were evaluated clinically and mycologically 30 and 60 days after completion of the treatment, which was considered effective when clinical signs and symptoms had disappeared and the mycological cultures were negative. Thirty days after treatment, the percent healing rate was 77 and 75 for the groups treated with ajoene and terbinafine, respectively. Sixty days after treatment, the healing rate 73% and 71% for the groups treated with ajoene and terbinafine, respectively. These results and those obtained in previous studies confirm that ajoene is a new agent for the topic treatment of superficial mycoses, and for the first time show the therapeutic usefulness of an inhibitor of phospholipids biosynthesis in eukaryotes.

Seasonal and nocturnal domiciliary human landing/biting behaviour of Lutzomyia (Lutzomyia) evansi and Lutzomyia (Psychodopygus) panamensis (Diptera; Psychodidae) in a periurban area of a city on the Caribbean coast of eastern Venezuela (Barcelona; Anzoátegui State).

In recent years, in addition to American cutaneous leishmaniasis (ACL), a significant number of cases of American visceral leishmaniasis (AVL) have been reported in periurban areas of Barcelona city (Anzoátegui State, Venezuela). We studied the bionomics of Lutzomyia (Lutzomyia) evansi and Lutzomyia (Psychodopygus) panamensis, possible vectors of AVL and ACL, respectively, in El Rincón, a periurban village of that city. To evaluate the seasonal domiciliary landing/biting activity of sandflies on human bait, a house was chosen in El Rincón. Landing catches were carried out between 18:00 and 06:00, once a month for a year. The results show the presence of 2 species, Lu. (Lu.) evansi (89.9%) and Lu. (Psy.) panamensis (10.1%). Lu. evansi was most abundant in the months of October and July, associated with the bimodal cycle of annual rainfall in the area. Maximum landing/biting activity of Lu. evansi was observed at 24:00 and 03:00. These findings suggest that at this time of the year and at these hours there is heightened risk of the transmission of AVL. Lu. panamensis monthly abundance also shows a direct association with rainfall and maximum landing/biting activity was observed between 02:00 and 03:00. The lower domiciliary abundance of Lu. panamensis suggests its greater importance in the extradomiciliary transmission of ACL.

Epidemiologic characterization of American cutaneous leishmaniasis in an endemic region of eastern Venezuela.

The status of American cutaneous leishmaniasis was investigated from 1985 to 1991 to provide an epidemiologic characterization of the disease in Bergantin, a rural community in the northeastern part of Anzoátegui State, Venezuela. The study revealed the presence of the infection during the period analyzed, with an average incidence of 50.2 cases per 10,000 inhabitants and this number has increased 1.5 times during the last two years. Three villages where clinical cases had been recorded were selected for a comparison of their prevalence data. These villages comprise the human population in the high and low altitude limits of Bergantin. Immunologic assessment of the inhabitants used two different antigen preparations to examine responses to parasites associated with the cutaneous and visceral forms of the disease. The leishmanin skin test (LST) was used in a sample of 276 individuals (46.3% of the inhabitants) and resulted in an overall positivity of 16.7%. The percentage of LST positivity varied with age and sex, yet analysis of this response and the prevalence for each village reflected the specific characteristics of these localities. La Montaña, situated at 800 meters above sea level, had the highest prevalence (800 cases per 10,000 inhabitants) and the most positive LST response (21.2%) in comparison with the two other villages situated at a lower altitude (300 meters above sea level).

Scorpion poisoning in the Acosta and Caripe Counties of Monagas State, Venezuela. part 1: characterization of some epidemiological aspects.

Scorpion poisoning was surveyed in Acosta and Caripe counties, located in the Turimiquire subregion of Monagas State, Venezuela, aiming to expand information on stings by characterizing some epidemiological aspects. From 1987 to 1993, 298 cases of scorpion stings were recorded in Acosta and Caripe counties. Acosta had 212 cases, with an annual incidence rate of 18.3 (cases per 10,000 inhabitants) and a period median incidence rate of 128 . The scorpion poisoning index is 4.18 times greater in Acosta than in Caripe, confirming the former as a hyperendemic zone for this type of injury, with a phenomenon of cyclical temporal fluctuations and an upward trend. This area is infested with scorpions of the genus Tityus. Our results show that the region surveyed in Monagas State is endemic for scorpion stings, posing a major public health problem.

Efficacy of ajoene, an organosulphur derived from garlic, in the short-term therapy of tinea pedis.

The present report shows the efficacy of ajoene, a garlic-derived organic trisulphur, for short-term therapy of tinea pedis. The use of ajoene as a 0.4% (w/w) cream resulted in complete clinical and mycological cure in 27 of 34 patients (79%) after 7 days of treatment. The remaining seven patients (21%) achieved complete cure after seven additional days of treatment. All patients were evaluated for recurrence of mycotic infections 90 days after the end of treatment, yielding negative cultures for fungus. These results show that ajoene is an alternative, efficient and low-cost antimycotic drug for short-term therapy of tinea pedis. The fact that ajoene can be easily prepared from an alcoholic extract of garlic may make it suitable for Third World public health care.

Evidence for direct coupling of primary agonist-receptor interaction to the exposure of functional IIb-IIIa complexes in human blood platelets. Results from studies with the antiplatelet compound ajoene.

Ajoene, (E,Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide, is a potent antiplatelet compound isolated from alcoholic extracts of garlic. In vitro, ajoene reversibly inhibits platelet aggregation as well as the release reaction induced by all known agonists. In this paper we show that ajoene has a unique locus of action, that is not shared by any other known antiplatelet compound. For example, ajoene inhibits agonist-induced exposure of fibrinogen receptors, as well as intracellular responses such as activation of protein kinase C and the increase in cytoplasmic free calcium induced by receptor-dependent agonists (collagen, ADP, PAF, low-dose thrombin). On the other hand, with agonists that can by-pass (at least partially) the receptor-transductor-effector sequence, such as high-dose thrombin, PMA, NaF, only the exposure of fibrinogen receptors is blocked by ajoene. Binding of fibrinogen to chymotrypsin-treated platelets is only slightly inhibited by ajoene. The results reported here also show that: (a) ajoene does not act as a calcium chelator, does not impair the initial agonist-receptor interaction and does not influence the basal levels of intracellular inhibitors of platelet activation such as cyclic GMP; (b) the locus of action of ajoene is a yet unknown molecular step that links, in the case of physiological agonists, specific agonist-receptor complexes to the sequence of the signal transduction system on the plasma membrane of platelets. In the case of non-physiological, receptor-independent agonists (PMA, NaF), we can only speculate on the hypothesis that they somehow mimic the effect of the agonist-receptor complexes on the signal transduction system; and (c) the exposure of fibrinogen receptors is not a direct consequence of other intracellular processes. These observations clearly show, for the first time, that the exposure of fibrinogen receptors is a membrane event proximally and obligatorily coupled to the occupancy of other membrane receptors by their agonists without any intervention by the cytoplasmic biochemical processes. Additional results support the involvement of G-proteins in these early events of platelet activation. Furthermore, a role of the beta tau subunits of G-proteins in the exposure of fibrinogen receptors is proposed.

Reversible prevention of platelet activation by (E,Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide (ajoene) in dogs under extracorporeal circulation.

Ajoene ((E,Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide), an organosulfur compound derived from garlic inhibits platelet activation induced ex vivo by all known agonists. The effect of ajoene on the thrombocytopenia associated with the circulation of blood through extracorporeal devices such as dialyzers or oxygenators was studied under the following conditions: Ex vivo using fresh, heparinized human blood, circulating through a dialyzer or oxygenator, and in vivo, in dogs subjected to extracorporeal circulation. In both experimental conditions ajoene proved very efficacious in preventing platelet loss (60-65% loss in controls vs. 15-20% loss in the presence of ajoene, p less than 0.01). Moreover, recuperation of platelet function was achieved after 3-4 h in the in vivo experiments.

The molecular basis of the antiplatelet action of ajoene: direct interaction with the fibrinogen receptor.

Ajoene, the major antiplatelet compound derived from garlic inhibits the fibrinogen-supported aggregation of washed human platelets (ID50 = 13 microM) and, inhibits binding of 125I-fibrinogen to ADP-stimulated platelets (ID50 = 0.8 microM). In both cases, the inhibition is of the mixed non-competitive type. Furthermore, fibrinogen-induced aggregation of chymotrypsin-treated platelets is also inhibited by ajoene in a dose-dependent manner (ID50 = 2.3 microM). Other membrane receptors such as ADP or epinephrine receptors are not affected by ajoene. Ajoene strongly quenches the intrinsic fluorescence emission of purified glycoproteins IIb-IIIa (ID50 = 10 microM). These results indicate that the antiaggregatory effect of ajoene is causally related to its direct interaction with the putative fibrinogen receptor.

Protein and glycoprotein abnormalities in platelets from human Chediak-Higashi syndrome: polyacrylamide gel electrophoretic study of platelets from five patients.

Polyacrylamide electrophoretic analysis of proteins and Tritium-labelled glycoproteins of the platelets from five patients with Chediak-Higashi Syndrome shows the existence of marked quantitative differences when compared to normal platelets. While the glycoprotein abnormalities are solely related to the plasma membrane, some of the abnormalities detected in the Coomasie blue pattern are probably representative of defects related to the dense bodies and the alpha-granules. Some of the abnormalities found may, in part, explain the variability of aggregatory responses described in these patients, as well as the marked tendency towards desaggregation exhibited by platelets from humans with the Chediak-Higashi Syndrome.

The storage pool deficiency in platelets from humans with the Chédiak-Higashi syndrome: study of six patients.

Functional and biochemical studies of platelets from human Chédiak-Higashi syndrome (CHS) are scarce and/or incomplete. In the present report, the aggregation response to a variety of inducers of platelet aggregation, the content of the dense granule constituents ATP, ADP, serotonin and calcium, the secretion of ATP, ADP, and calcium induced by thrombin, the total content of magnesium, the incorporation of 14C-adenine in the cytoplasmic pool of adenine nucleotides, as well as the content of intracellular cyclic-AMP, have been quantitated in six patients with CHS. Furthermore, data is presented on the kinetics of uptake of radiolabelled serotonin and its storage in human CHS platelets. An abnormal aggregation behaviour was found in all patients. However, the response of CHS platelets to the different inducers studied did not show a uniform pattern. The total content and the maximal amounts of the dense granule constituents secretable by thrombin were greatly decreased in all six patients. Total magnesium content was similar to that of normal platelets. The ATP/ADP ratio was higher than in controls. Uptake of radiolabelled serotonin by CHS platelets closely followed the uptake by normal platelets; during the first 2-3 min, however, incorporation of the amine by CHS platelets came rapidly to a plateau which contrasts with the steady, linear increase in uptake found in controls. CHS platelets loaded with radiolabelled serotonin and gel-filtered, showed a spontaneous release of radioactivity not observed in normal platelets under the same conditions. The cyclic-AMP content of CHS platelets was similar to that of normals. In contrast to platelets from patients with storage pool disease, the secretable calcium from CHS platelets represents a 67% of total platelet calcium (61% in normals), suggesting that the absolute values for the non-secretable portion in CHS platelets must be very low. The results reported confirm the existence of a true storage pool deficiency of the dense granule constituents as a common defect in CHS platelets. The variety of responses among patients, to the different aggregatory stimuli studied, can not be solely ascribed to the storage pool deficiency described.

Effects of garlic extract and of three pure components isolated from it on human platelet aggregation, arachidonate metabolism, release reaction and platelet ultrastructure.

We studied the effect of the methanol extract of garlic bulbs (EOG) and of three pure components isolated from it (F1, F2, F3), on human platelet aggregation induced by ADP, epinephrine, collagen, thrombin, arachidonate, PAF, and the ionophore A-23187. Incubation of PRP with EOG, either in methanol or in homologous PPP, inhibits platelet aggregation induced by all of the above mentioned agonists. F1, F2, and F3 also inhibit platelet aggregation, however, F3 was about four times more potent. Addition of EOG or F3 to platelets that have already been irreversibly aggregated by 10 microM ADP, induces rapid deaggregation. Inhibition of aggregation was still present after three hours. The inhibitory effect persisted even after the treated platelets were Gel-Filtered (GFP) or separated from plasma through a metrizamide gradient and resuspended in new homologous PPP. Thrombin-induced release of ATP from GFP was inhibited by 75-80% after EOG or F3 treatment. Incorporation of [3-H]-arachidonate by intact platelets was decreased by 50-60% in treated platelets. However, platelets incubated with the inhibitors after incorporation of radiolabeled arachidonate, although did not aggregate, produced, after thrombin activation similar amounts of radiolabeled TXB2 and lipoxygenase products as the controls. Electron microscopy of inhibited platelets, in the presence of thrombin, showed no degranulation but an increase of spherical forms. Our results suggest that the effects described might be mediate by a perturbation of the physicochemical properties of the plasma membrane rather than by affecting arachidonate or calcium metabolism in the cells. Chemical structures of F1, F2 and F3 have been provisionally assigned: F1 is diallytrisulfide, F2 is 2-vinyl-1,3-dithiene, and F3 is most probably allyl 1,5-hexadienyltrisulfide.