Impact of antagonistic yeasts from wine grapes on growth and mycotoxin production by Alternaria alternata.

AIMS: Alternaria alternata is a major contaminant of wine grapes, meaning a health risk for wine consumers due to the accumulation of toxic metabolites. To develop a successful biofungicide, the effectiveness of epiphytic wine grape yeasts against A. alternata growth and toxin production was assessed in vitro under temperature and aW conditions that simulate those present in the field. METHODS AND RESULTS: The effect of 14 antagonistic yeasts was evaluated on growth and alternariol (AOH), alternariol monomethyl ether (AME) and tenuazonic acid (TA) production by three A. alternata strains in a synthetic medium with composition similar to grape (SN) at three temperatures (15, 25 and 30°C). All Metschnikowia sp. yeast strains evaluated completely prevented A. alternata growth and mycotoxin production at all temperatures in SN medium. Meanwhile, the growth inhibition exerted by Starmerella bacillaris yeast strains was higher at 30°C, followed by 25 and 15°C, being able to show a stimulating or inhibiting effect. Hanseniaspora uvarum yeast strains showed a growth promoting activity higher at 15°C, followed by 25 and 30°C. Even at conditions where A. alternata growth was stimulated by the S. bacillaris and H. uvarum yeasts, high inhibitions of mycotoxin production (AOH, AME and TA) were observed, indicating a complex interaction between growth and mycotoxin production. CONCLUSION: There is a significant influence of temperature on the effectiveness of biocontrol against A. alternata growth and mycotoxin production. Metschnikowia sp. strains are good candidates to compose a biofungicide against A. alternata. SIGNIFICANCE AND IMPACT OF THE STUDY: Among the different antagonistic yeasts evaluated, only Metschnikowia sp. strains were equally effective reducing A. alternata growth and mycotoxin at different temperatures underlining the importance of considering environmental factors in the selection of the antagonists.

Factors of the epidemiological triad that influence the persistence of human papilloma virus infection in women with systemic lupus erythematosus.

We studied the epidemiologic triad-related factors influencing human papilloma virus (HPV) persistence in Mexican women with systemic lupus erythematosus (SLE). Patients aged ≥18 years with SLE (American College of Rheumatology criteria), with and without HPV persistence, were selected. Groups were analyzed by (1) host: clinical disease characteristics; (2) agent: (I) infectious (prevalence, incidence, HPV genotype and co-infections (≥2 HPV genotypes or mycoplasmas)), (II) chemical (contraceptives and immunosuppressive drugs) and (III) physical (vitamin D deficiency) and (3) environment. A total of 121 SLE patients were selected over a two-year period. (1) Host: mean age 45.8 years and disease duration 12.7 years. (2) Agent: (I) infectious. HPV infection prevalence in the second sample was 26.4%, high-risk HPV genotypes 21.5% and co-infections 7.4%. HPV infection incidence was 13.2%, persistence 13.2% and clearance 15.7%. (II) Chemical: use of oral hormonal contraceptives 5% and immunosuppressive treatment 97.5%. (III) Physical: Vitamin D levels were similar in both groups. (3) Environment: (I) natural. A total of 60.6% of patients were residents of Puebla City. (II) Social: The mean education level was 10.9. Poverty levels were: III degree 52.4%, IV degree 28% and II degree 17%. (III) Cultural behavioral: Onset of sexual life was 20.5 years, 10% had ≥3 sexual partners and 51.2% were postmenopausal. In conclusion, no factor of the epidemiologic triad was associated with HPV infection prevalence.

Water activity and temperature effects on growth and mycotoxin production by Alternaria alternata strains isolated from Malbec wine grapes.

AIMS: To study the effects of water activity (aW ; 0·99, 0·98, 0·97, 0·96 and 0·95), temperature (15, 25 and 30°C), incubation time (7-28 days), and their interactions on mycelial growth and alternariol (AOH), alternariol monomethyl ether (AME) and tenuazonic acid (TA) mycotoxin production on a synthetic nutrient (SN) media similar to grape composition by three strains of Alternaria alternata isolated from wine grapes from Argentina. METHODS AND RESULTS: Interacting conditions of aW , temperature and time of incubation were used to examine growth and mycotoxin production. All strains were able to grow at 0·95 aW , but maximum growth rates were obtained at 0·99 aW and 25°C. Maximum levels of AOH, AME and TA were obtained at 0·99 aW and 25°C, but high amounts of TA were also obtained at 0·96 aW and 15 or 30°C. Production of AOH and AME was favoured over TA at 25°C. TA levels were more sustained than AOH and AME. CONCLUSION: The optimum and marginal conditions for growth and mycotoxin production by A. alternata on a SN media similar to grape composition were in agreement, but certain stressful conditions for growth evaluated also promote mycotoxin production. SIGNIFICANCE AND IMPACT OF THE STUDY: Temperature and aW conditions that allows growth and mycotoxin production are those normally found during wine grape ripeness in the field. Therefore, efforts should be made to prevent Alternaria presence and mycotoxin production in wine grapes.

Impact of liver steatosis on the correlation between liver stiffness and fibrosis measured by transient elastography in patients coinfected with human immunodeficiency virus and hepatitis C virus.

We assessed the effect of different hepatic conditions such as fibrosis, steatosis and necroinflammatory activity on liver stiffness as measured by transient elastography in HIV/HCV-coinfected patients. We studied all consecutive HIV/HCV-coinfected patients who underwent liver biopsy and elastography between January 2007 and December 2008. Liver fibrosis was staged following METAVIR Cooperative Study Group criteria. Steatosis was categorized according to the percentage of affected hepatocytes as low (≤10%), moderate (<25%) and severe (≥25%). A total of 110 patients were included. Fibrosis was distributed by stage as follows: F0, n = 13; F1, n = 47; F2, n = 29; F3, n = 18; and F4, n = 3. Liver biopsy revealed the presence of hepatic steatosis in 68 patients (low to moderate, n = 53; and severe n = 15). By univariate regression analysis, fibrosis, necroinflammatory activity, and the degree of steatosis were correlated with liver stiffness. However, in a multiple regression analysis, steatosis and fibrosis were the only independent variables significantly associated with liver stiffness. With a cut-off of 9.5 kPa to distinguish patients with F ≤ 2 from F ≥ 3, elastography led to a significantly higher number of misclassification errors (25%vs 5%; P = 0.014), most of which were false positives for F ≥ 3. Our study suggests that the correlation between liver stiffness and fibrosis as estimated by transient elastography may be affected by the presence of hepatic steatosis in HIV/HCV-coinfected patients.

Comparison of transient elastography and liver biopsy for the assessment of liver fibrosis in HIV/hepatitis C virus-coinfected patients and correlation with noninvasive serum markers.

Transient elastography (FibroScan) is a novel, rapid and noninvasive technique to assess liver fibrosis. Our objective was to compare transient elastography (TE) and other noninvasive serum indexes as alternatives to liver biopsy in HIV/hepatitis C virus (HCV)-coinfected patients. The fibrosis stage (METAVIR Score), TE, the aspartate aminotransferase-to-platelet ratio index, the Forns fibrosis index, FIB-4 and HGM-2 indexes were assessed in 100 patients between January 2007 and January 2008. The diagnostic values were compared by calculating the area under the receiver operating characteristic curves (AUROCs). Using TE, the AUROC (95% CI) of liver stiffness was 0.80 (0.72-0.89) when discriminating between F 2, 0.93 (0.85-1.00) when discriminating between F 3 and 0.99 (0.97-1.00) when discriminating between F or= 3, the AUROCs of TE were significantly higher than those obtained with the other four noninvasive indexes. Based on receiver operating characteristic curves, three cutoff values were chosen to identify F or= 3 (>or=11 kPa) and F4 (>or=14 kPa). Using these best cutoff scores, the negative predictive value and positive predictive value were 81.1% and 70.2% for the diagnosis of F or= 3 and 100% and 57.1% for the diagnosis of F4. Thus, Transient elastography accurately predicted liver fibrosis and outperformed other simple noninvasive indexes in HIV/HCV-coinfected patients. Our data suggest that TE is a helpful tool for guiding therapeutic decisions in clinical practice.

Impact of water activity and temperature on growth and alternariol and alternariol monomethyl ether production of Alternaria alternata isolated from soybean.

The objective of this study was to determine the effect of water activity (a(w); 0.995, 0.98, 0.96, 0.94, 0.92, and 0.90), temperature (5, 18, 25, and 30 degrees C), incubation time (7 to 35 days), and their interactions on mycelial growth and alternariol (AOH) and alternariol monomethyl ether (AME) production. Two Alternaria alternata strains isolated from soybeans in Argentina were grown on 2% soybean extract agar. Maximum growth rates were obtained at the highest a(w) (0.995) and 25 degrees C, with growth decreasing as the water availability of the medium was reduced. Maximum amount of AOH was produced at 0.98 a(w) and 25 degrees C for both strains. Maximum AME production was obtained for both strains at 30 degrees C but different a(w) values, 0.92 and 0.94, for the strains RC 21 and RC 39, respectively. The concentrations of both toxins varied considerably depending on the a(w) and temperature interactions assayed. The two metabolites were produced from 5 to 30 degrees C and at a(w) values of 0.92 to 0.995. Although at 5 and 18 degrees C little mycotoxin was produced at a(w) lower than 0.94. Two-dimensional profiles of a(w) by temperature interactions were developed from these data to identify areas where conditions indicate a significant risk from AOH and AME accumulation on soybeans. All the conditions of a(w) and temperature that resulted in maximum production of both toxins are those found during soybean development in the field. Thus, field conditions are likely to be conducive to optimum A. alternata growth and toxin production.

Frequency of Toxoplasma gondii in pork meat in Ocotlán, Jalisco, Mexico.

Toxoplasmosis is an infection caused by Toxoplasma gondii, an intracellular obligate parasite. Its transmission has usually been attributed to ingestion of undercooked or raw meat. The frequency of T. gondii in pork, the most common meat for human consumption in Jalisco, Mexico, is unknown; in Guadalajara city high prevalence of human toxoplasmosis has been documented. Forty-eight samples of pork meat from butcher shops in Ocotlán city were analyzed. Through bioassay, 50 g of tissue was homogenized in an acidic pepsin solution and inoculated subcutaneously to previously immunosuppressed mice. Blood samples from the mice tail vein were obtained before inoculation and 7, 14, 28, and 45 days postinoculation to analyze anti-Toxoplasma immunoglobulin (Ig) M and IgG antibody kinetics by indirect enzyme-linked immunosorbent assay. For histopathology, small fragments of the brain, lungs, heart, and skeletal muscle were extracted on day 45 and were stained with hematoxylin and eosin. Also, DNA was extracted from the pork meat for PCR amplification of the B1 gene. Even though all pork samples were negative by histopathology and PCR, IgG and IgM antibodies against T. gondii were detected in 1 of the 48 inoculated mice, reflecting a frequency of 2.1% positive pork meat, which is lower than expected but similar to that found in other regions.

Effect of environmental factors on tenuazonic acid production by Alternaria alternata on soybean-based media.

AIMS: To determine the effects of water activity (a(W); 0.995-0.90), temperature (5, 18, 25 and 30 degrees C), time of incubation (7-35 days) and their interactions on tenuazonic acid (TA) production on 2% soybean-based agar by two Alternaria alternata strains isolated from soybean in Argentina. METHODS AND RESULTS: TA production by two isolates of A. alternata was examined under interacting conditions of a(W), temperature and time of incubation on 2% soybean-based agar. Maximum TA production was obtained for both strains at 0.98 a(W), but at 30 and 25 degrees C for the strains for RC 21 and RC 39, respectively. The toxin concentration varied considerably depending on a(W), temperature, incubation time and strain interactions. TA was produced over the temperature range from 5 to 30 degrees C and a(W) range from 0.92 to 0.995, however at 5 and 18 degrees C little TA was produced at a(W) below 0.94. Contour maps were developed from these data to identify areas where conditions indicate a significant risk for TA accumulation. CONCLUSIONS: The optimum and marginal conditions for TA production by A. alternata on soybean-based agar were identified. The results indicated that TA production by A. alternata is favoured by different temperatures in different strains. SIGNIFICANCE AND IMPACT OF THE STUDY: Data obtained provide very useful information for predicting the possible risk factors for TA contamination of soybean as the a(W) and temperature range used in this study simulate those occurring during grain ripening. The knowledge of TA production under marginal or sub-optimal temperature and a(W) conditions for growth are relevant as improper storage conditions accompanied by elevated temperature and moisture content in the grain can favour further mycotoxin production and lead to reduction in grain quality.

Determination of mycobiota and mycotoxins in pig feed in central Argentina.

AIMS: To evaluate the mycobiota and natural levels of aflatoxins, fumonisins and zearalenone present in compound feed and home-corn grains intended for fattening pigs. METHODS AND RESULTS: Total fungi, Fusarium and Aspergillus species occurrence were examined. Aflatoxins and zearalenone were detected by thin-layer chromatography and fumonisins by high-pressure liquid chromatography. Fungal counts were generally higher than 1 x 10(5) colony forming units (CFU) ml(-1). Aspergillus flavus, Aspergillus parasiticus and Fusarium verticillioides were the most prevalent species. FB(1) and FB(2) were detected in all feed and corn samples. Aflatoxin B(1) was detected in 33.33% of initial and growing feed and in 44.44% of final feed samples. It was not detected in corn samples. All feed and corn samples were negative for AFB(2), AFG(1), AFG(2) and ZEA presence during all growing stages tested. CONCLUSIONS: Fungal counts at all growing periods exceeded the levels proposed as feed hygienic quality limits. Aflatoxin levels in all feeds and fumonisin levels in many samples were higher than the established regulations. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of mycotoxins indicates the existence of contamination. This fact requires periodic monitoring to prevent the occurrence of mycotoxicosis in animal production, to reduce the economic losses and to minimize hazards to human health.

Complicaciones obstétricas relacionadas con la terapia antirretroviral en gestantes infectadas por el VIH / Obstetric complications related to antiretroviral therapy in pregnant women with HIV infection

IntroducciónEl porcentaje de gestantes infectadas por VIH que demandan embarazo ha aumentado en los países desarrollados debido a la estabilidad de la infección y la disminución de la transmisión vertical por los tratamientos antirretrovirales (TAR) y las medidas preventivas. Sin embargo, existe poca información respecto al efecto del TAR sobre el embarazo.MétodosEstudio retrospectivo de las gestantes infectadas por VIH con TAR controladas en el Hospital La Paz entre los años 2000-2017. Se estudiaron las complicaciones maternofetales.ResultadosSe recogieron 141 gestaciones en 112 mujeres infectadas por VIH. El TAR más utilizado fue la combinación de 2 inhibidores de la transcriptasa inversa análogos nucleosídicos+1 inhibidor de la proteasa (58,1%), con diferencias significativas entre los distintos tratamientos en cuanto a la carga viral plasmática, siendo indetectable en mayor medida con 2 inhibidores de la transcriptasa inversa análogos nucleosídicos +1 inhibidor de la transcriptasa inversa no nucleosídico, segunda pauta más utilizada. Las tasas de neonatos a término de bajo peso (<2.500g) (11,3%), partos pretérmino (11,1%) y rotura prematura de membranas pretérmino (5,6%) fueron mayores que en la población general. Aunque no hubo asociación, estas complicaciones fueron más frecuentes en gestantes con un inhibidor de la proteasa/ritonavir. No se relacionaron con la carga viral plasmática. No se encontró aumento en la tasa de interrupciones gestacionales, malformaciones ni diabetes gestacional.ConclusiónEn las gestantes infectadas por VIH con TAR está aumentada la tasa de neonatos a término de bajo peso, prematuridad y rotura prematura de membranas pretérmino en comparación con la población general, relacionándose especialmente con el tratamiento con un inhibidor de la proteasa, aunque sin asociación significativa.

IntroductionThe percentage of HIV-infected pregnant women seeking pregnancy has increased in developed countries due to the stability of the infection and the decrease in vertical transmission due to antiretroviral treatment (ART) and preventive measures. However, there is little information regarding the effect of ART on pregnancy.MethodsRetrospective study of HIV-infected pregnant women on ART monitored at Hospital La Paz between 2000-2017. Maternal-foetal complications were studied.ResultsOne hundred and forty-one gestations were collected in 112 HIV-infected women. The most commonly used ART was the combination of 2 nucleoside reverse transcriptase inhibitor analogues+1 protease inhibitor (58.1%), with significant differences between the different treatments in terms of plasma viral load being undetectable to a greater extent with 2 nucleoside reverse transcriptase inhibitor analogues+1 non-nucleoside reverse transcriptase inhibitor, the second most used regimen. The rates of low birth weight (<2,500g) term neonates (11.3%), preterm delivery (11.1%) and preterm premature rupture of membranes (5.6%) were higher than in the general population. Although there was no association, these complications were more frequent in pregnant women with a protease inhibitor/ritonavir. They were not related to plasma viral load. No increase in the rate of gestational terminations, malformations or gestational diabetes was found.ConclusionHIV-infected pregnant women on ART have an increased rate of low birth weight, prematurity, and preterm premature rupture of membranes at term compared to the general population, especially related to treatment with protease inhibitor, although without significant association.

Autonomous Biological Control of Dactylopius opuntiae (Hemiptera: Dactyliiopidae) in a Prickly Pear Plantation With Ecological Management.

It is broadly known that the conservation of biological diversity in agricultural ecosystems contributes to pest control. This process was studied in a prickly pear plantation (Opuntia megacantha and Opuntia ficus-indica) located in central Mexico. No insecticides have been used on this plantation since 2000, and local farmers believe that the presence of different species of insects limits the growth of the wild cochineal (Dactylopius opuntiae Cockerell), which is one of the main pests in this crop. From August 2012 to November 2013, we estimated the number of cochineal per stem in the plantation and determined its spatial distribution pattern. In order to identify signs of population regulation, we obtained histograms of the frequency distribution of the size of the clusters and determined if distribution is adjusted to a power function (power law). We identified the cochineal predators and determined the correlation in their abundances. The greater abundance of cochineal occurred between summer and autumn while the minimum value was recorded in spring. The frequency distribution of the cochineal clusters had a high level of adjustment to a power function, suggesting the presence of population regulation processes. Six species that prey on cochineal were identified. Laetilia coccidivora and Hyperaspis trifurcata were the most active and their abundance was significantly correlated with the abundance of cochineal. We found that the probability of extinction of these insects in a cladode increases with its density, since the density and predator activity also increased. It is likely that, under these conditions, the cochineal have established an autonomous control.

Anti-diabetic effect on alloxanized and normoglycemic rats and some pharmacological evaluations of Tournefortia hartwegiana.

The purpose of the present investigation was to assess the pharmacological properties of Tournefortia hartwegiana Steud (Boraginaceae), used in traditional medicine for the treatment of diabetes, diarrhea and kidney pain in Morelos, Mexico. Administration of methanol extract from aerial parts of Tournefortia hartwegiana (310 mg/kg body weight/day) for 10 days, to normoglycemic and alloxan-induced diabetic rats, significantly lowered their blood glucose levels (37 and 36%, respectively, p<0.05). The anti-diabetic and hypoglycemic activities due to the MeOH extract were similar to those produced by metformin at 120 mg/kg (positive control, p<0.05). In contrast, the hexane, dichloromethane and MeOH extracts from the same species showed no significant spasmolytic effect and did not have activity in antibacterial and Artemia salina toxicity bioassays.

Genetic variability and fumonisin production by Fusarium proliferatum isolated from durum wheat grains in Argentina.

Fusarium proliferatum is a member of the Fusarium fujikuroi species complex (FFSC) involved in the maize ear rot together with Fusarium verticillioides, which is a very closely related species. Recently, different studies have detected natural fumonisin contamination in wheat kernels and most of them have shown that the main species isolated was F. proliferatum. Fusarium strains obtained from freshly harvested durum wheat samples (2008 to 2011 harvest seasons) from Argentina were characterized through a phylogenetic analysis based on translation elongation factor-1 alpha (EF-1α) and calmodulin (CaM) genes, determination of mating type alleles, and evaluation of fumonisin production capability. The strains were identified as F. proliferatum (72%), F. verticillioides (24%) and other Fusarium species. The ratio of mating type alleles (MAT-1 and MAT-2) obtained for both main populations suggests possible occurrence of sexual reproduction in the wheat fields, although this seems more frequent in F. proliferatum. Phylogenetic analysis revealed greater nucleotide variability in F. proliferatum strains than in F. verticillioides, however this was not related to origin, host or harvest year. The fumonisin-producing ability was detected in 92% of the strains isolated from durum wheat grains. These results indicate that F. proliferatum and F. verticillioides, among the fumonisin producing species, frequently contaminate durum wheat grains in Argentina, presenting a high risk for human and animal health.

Relation between coumarate decarboxylase and vinylphenol reductase activity with regard to the production of volatile phenols by native Dekkera bruxellensis strains under 'wine-like' conditions.

Dekkera/Brettanomyces bruxellensis is considered a major cause of wine spoilage, and 4-ethylphenol and 4-ethylguaiacol are the most abundant off-aromas produced by this species. They are produced by decarboxylation of the corresponding hydroxycinnamic acids (HCAs), followed by a reduction of the intermediate 4-vinylphenols. The aim of the present study was to examine coumarate decarboxylase (CD) and vinylphenol reductase (VR) enzyme activities in 5 native D. bruxellensis strains and determine their relation with the production of ethylphenols under 'wine-like' conditions. In addition, biomass, cell culturability, carbon source utilization and organic acids were monitored during 60 days. All strains assayed turned out to have both enzyme activities. No significant differences were found in CD activity, whilst VR activity was variable among the strains. Growth of D. bruxellensis under 'wine-like' conditions showed two growth phases. Sugars were completely consumed during the first growth phase. Transformation of HCAs into ethylphenols also occurred during active growth of the yeast. No statistical differences were observed in volatile phenol levels produced by the strains growing under 'wine-like' conditions, independently of the enzyme activity previously recorded. Furthermore, our results demonstrate a relationship between the physiological state of D. bruxellensis and its ability to produce ethylphenols. Inhibition of growth of D. bruxellensis in wine seems to be the most efficient way to avoid ethylphenol production and the consequent loss of wine quality.

Toxigenic fungal species and natural occurrence of mycotoxins in crops harvested in Argentina / Especies fúngicas toxigénicas y ocurrencia natural de micotoxinas en cultivos y productos cosechados en Argentina

Abstract Mycotoxins are secondary metabolites produced by fungal species that mainly belong to Aspergillus, Fusarium, Penicillium and Alternaria, which can grow in a variety of crops including cereals, oilseeds and fruits. Consequently, their prevalence in foods and by-products not only affects human and animal health but also causes important losses in both domestic and international markets. This review provides data about toxigenic fungal species and mycotoxin occurrence in different crops commonly grown in Argentina. This information will be relevant to establish adequate management strategies to reduce the impact of mycotoxins on human food and animal feed chains and to implement future legislation on the maximum permitted levels of these fungal metabolites.

Resumen Las micotoxinas son metabolitos secundarios producidos por diferentes especies fúngicas pertenecientes, principalmente, a los géneros Aspergillus, Fusarium, Penicillium y Alternaria. Dichos microorganismos pueden crecer en una gran variedad de cultivos, entre los que se incluyen cereales, oleaginosas y frutas. La presencia de micotoxinas en alimentos y subproductos no sólo afecta la salud humana y animal, sino que también causa pérdidas importantes en los mercados nacionales e internacionales. Esta revisión proporciona datos sobre la prevalencia de especies fúngicas toxigénicas y de micotoxinas en diferentes cultivos y productos cosechados en Argentina. Dicha información será relevante para establecer estrategias de manejo adecuadas para reducir la entrada de las micotoxinas en las cadenas alimentarias del hombre y de los animales, así como para establecer futuras legislaciones sobre los niveles máximos permitidos de dichos metabolitos.

Nanoemulsions for dermal controlled release of oleanolic and ursolic acids: In vitro, ex vivo and in vivo characterization.

The aim of the present study was to design and optimize a nanoemulsion for dermal administration of mixtures of natural or synthetic pentacyclic triterpenes with recognized anti-inflammatory activity. The composition of the developed nanoemulsions was obtained from pseudo-ternary phase diagrams, composed of castor oil as the oil phase, labrasol as the surfactant, transcutol-P as co-surfactant and propylene glycol as the aqueous phase. Different ratios of surfactant/co-surfactant mixture (Smix) (4:1, 3:1, 2:1, 1:1, 1:2 and 1:4) were produced, and Smix 4:1 was chosen based on the greater area of optimal nanoemulsion conditions. Two different nanoemulsions of mean droplet size below 600 nm were produced, loading mixtures of natural or synthetic pentacyclic triterpenes, respectively. The viscosity of nanoemulsion containing natural pentacyclic triterpenes was 51.97±4.57 mPas and that loaded with synthetic mixtures was 55.33±0.28 mPas. The studies of release and skin permeation were performed using Franz diffusion cells, adjusting the release kinetics of both formulations to Korsmeyer-Peppas model. No significant differences in permeation parameters between the two nanoemulsions were observed. The amount of drug retained in the skin was higher than the amount of drug that has permeated, favoring a local action. The results of the in vivo tests demonstrated that the developed formulations were not toxic and not irritant to the skin. The formulation loading a mixture of natural triterpenes showed greater ability to inhibit inflammation than that loading the synthetic mixture. The findings clearly corroborate the added value of o/w nanoemulsions for dermal delivery of pentacyclic triterpenes.

Reproducibility of stand-alone continuous-wave Doppler recordings of aortic flow velocity across bioprosthetic valves.

Continuous-wave Doppler spectra of aortic flow velocity were recorded in duplicate in 20 consecutive patients with aortic porcine valves by 1 technician and 3 occasions: initially and 1 week and 1 month later. The highest maximal aortic velocity recorded from at least 2 transducer locations was taken from 5 consecutive beats that did not vary. The 120 tracings were coded and read by 1 observer. In blinded fashion, 20 records were read twice and 26 were read by 2 interpreters. Variability was calculated from the square root of pooled variances and expressed in meters per second and also related to the mean velocity and expressed as percent coefficient of variation for the following categories: interpretive [intraobserver +/- 0.019 (0.8%), interobserver +/- 0.071 (2.7%)], technical [duplication +/- 0.048 (1.9%)], temporal/biologic [+/- 0.125 (5.0%)]. Doppler measurements of aortic velocity can achieve excellent reproducibility by maintaining constant technique. With a methodologic variability of +/- 2%, the variability associated with the passage of time was significantly different at +/- 5% and was a result of fluctuations in the physiology of a few subjects. Thus, the technique can distinguish small method errors from minor drifts of the biology and, by implication, detect the onset of bioprosthetic degeneration.

Autosomal recessive spondylo-epi-metaphyseal dysplasia (Irapa type) in a Mexican family: delineation of the syndrome.

Three sibs from a Mexican mestizo family affected with a spondylo-epi-metaphyseal dysplasia were studied. The clinical, radiological, and genetic findings were similar to those previously described in Venezuelan Indians of the Irapa tribe. The present patients permit confirmation of the syndrome and provide evidence for autosomal recessive inheritance. Genetic drift is postulated.

Bioactive oleanolic acid saponins and other constituents from the roots of Viguiera decurrens.

The bisdesmoside oleanolic acid saponin, 3-0-(methyl-beta-D-glucuronopyranosiduronoate)-28-0-beta-D-glucopyranosyl-oleanolate along with nine known compounds (two diterpenic acids, one chromene, three triterpenes, one steroidal glycoside, and two monodesmoside oleanolic acid saponins), were obtained from Viguiera decurrens roots. The chemical structure of the bisdesmoside oleanolic saponin was determined by chemical and NMR spectral evidence. A mixture of monodesmoside saponins displayed cytotoxic activity against P388 and COLON cell lines (ED50= 2.3 and 3.6 microg/ml, respectively). Two of the known compounds showed insecticidal activity against the Mexican bean beetle larvae (Epilachna varivestis).

Potential use of antioxidants for control of growth and fumonisin production by Fusarium verticillioides and Fusarium proliferatum on whole maize grain.

The effect of interactions between two food grade antioxidants butylated hydroxyanisole (BHA) and propyl paraben (PP, 100, 200, 500 microg g(-1)) and water activity (a(w), 0.995, 0.98, 0.95) of irradiated maize on lag phase prior to growth, growth rate and fumonisin production by Fusarium verticillioides and Fusarium proliferatum was evaluated at 25 degrees C. Both antioxidants had an effect on growth characteristics, and fumonisin production. However, this was dependent on the dose used and the a(w) treatment. At 500 microg g(-1) BHA and PP increased the lag phase prior to growth, and reduced the growth rate of both Fusarium species significantly, especially at 0.95 a(w). Both antioxidants significantly reduced the production of fumonisin by both Fusarium species, especially at 0.98 and 0.95 a(w). These results suggest that these antioxidants have potential for treatment of maize grain for controlling growth of these mycotoxigenic species and prevent fumonisin accumulation.