Biomedical subjects
Publications and source records attributed to M A Calvo.
A study of one hundred Penicillium strains belonging to Raper and Thom's monoverticillate series was carried out. The data compiled led to the conclusion that there are no significant biochemical differences which would make possible an accurate separation of the strains belonging to the series.
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Authors report results of the study of a series of 50 children patients with Campylobacter enteritis. After insisting on the present frequency of this infectious agent as pathogen for human beings, they analyse the epidemiologic, clinic and therapeutic aspects.
The assay of hormone receptors in neoplastic tissues recognizes their sensitivity or autonomy with regard to the hormonal action. The hormone dependency of the activity of neoplastic tissues can be employed to select the cases having the highest probability to be benefited by the treatment with anti-hormones, castration or hypophysectomy, as in breast and prostatic cancers. Examining the case for prostatic cancer, the authors indicate that there is a good correlation between the predictive assay and the clinical evolution of the treated prostatic carcinoma employing the determination of cell receptors for 5-alpha-dihydrotestosterone (DHT) by exchange at 15 degrees C with the synthetic steroid methyltrienolone. The electrophoretic determination of binding of DHT to cell receptor a 4 degree C is a much less efficacious procedure.
The correlations between the physiological and morphological characteristics of various Microsporum strains were studied together with the inhibitory activities toward different microorganisms.
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The morphology of conidia in 211 species and 12 varieties belonging to the genus Penicillium Link ex Gray have been studied and compared. According to surface ornamentation, conidia have been classified into six groups: A, smooth-walled (7% of the species); B, delicately roughened (13%); C, warty (28%); D, echinate 910%); E, striate with low irregular ridges (36%); and F, striate with scarce high ridges or bars (6%). Whereas the first two groups are closely related in both shape and average size, a gradual reduction was observed in size and in the length/width (l/w) ratio in the remaining groups. Echinate conidia were globose, having the largest average size. Only four species produced conidia not surpassing 2 micrometers in diameter. Maximum length observed was 8 micrometers, and most elongated conidia had a l/w ratio of 3.5. Forty per cent of the species studied had globose conidia. Conidia of the monoverticillate species were generally smaller, more globose and frequently with ridges. In the Asymmetrica, the conidia were generally larger, and showed ridges in comparatively few species. Conidia of the Symmetrica, which were frequently striate with ridges, presented the most elongated forms. The largest average size was found in the conidia of the Polyverticillata which were generally warty. Finally, we have considered the variations in surface ornamentation of conidia during the evolution of the genus Penicillium and drawn attention to their possible relationship with certain habitats and ways of conidial dispersion.
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A total of 310 fungal strains isolated from starches intended for the manufacture of pharmaceuticals were tested to determine their toxicity to Brine shrimp (Artemia salina L.) larvae and Bacillus megaterium NRRL 1 366. Of them, 82 proved toxic for both biotests, 173 (82 + 91) toxic for at least one of the tests. The system based on the use of Brine shrimp larvae proved to be the more sensitive of the two assayed. Results are stated also for the different species of each genus.
Two strains of Aspergillus flavus Link ex Fr. and two strains of A. parasiticus Speare were cultured on crushed moist wheat (Triticum durum var. Pané no. 257) for aflatoxin production studies in correlation with morphological changes. The toxicogenic strains were adapted to the substratum by means of successive transfers at regular intervals (72 h.) The amount aflatoxins synthesized by the toxicogenic strains decreased gradually after succesive subculturing. The decrease was accompanied by marked morphological changes. One of the strains studied, A. flavus NRRL 3251, lost completely the capacity of aflatoxin synthesis after several subcultures, presenting at the same time strong morphological variations. A. flavus CBS 120.62 also lost its toxicogenicity after six subcultures.
Quantitative and qualitative studies were made of the fungi of the air in Barcelona City. The genera Cladosporium and Alternaria formed two of the most important components of the fungus population studied during a two-year period running from January 1976 through January 1978. Penicillium species formed the 16.3% of the total colonies while Aspergillus species represented only the 2.8%. The occurrence of the genera was greatly affected by climatic conditions. An attempt was made to summariza the data of various kinds of fungi on a volumetric basis. Most of the fungi reported here have been identified as far as genera.
During a two-year survey on the air-borne fungi in the atmosphere of Barcelona (Spain), the following genera were isolated in decreasing order: Aureobasidium, Rhizopus, Mucor, Arthrinium, Phoma, Fusarium, Trichoderma, and Botrytis.
During a two-year survey of the fungal flora present in the air of Barcelona, Spain, the following species of yeasts were isolated: Sporobolomyces roseus Kluyver et van Niel, Candida albicans (Robin) Berkhout, Rhodotorula glutinis (Fres.). Harrison var. glutinis and Rhodotorula minuta (Saito) Harrison. Diurnal and seasonal incidences are presented.
This paper summarizes the first results of a mycological survey on the spore content of the air in and outside of homes in Barcelona, Spain, including the records of several genera of microfungi isolated during a 15-month study period.
The genus Alternaria Nees formed one of the more important components of the fungus population of the air at Barcelone (Spain), during a two-year study, from February 1976 through January 1978. Results were based only on studied of colonies obtained by gravity-exposed plates. The occurrence of this genus was greatly affected by climatic conditions. In general. however, Alternaria appeared to prefer warmer weather. A total of six species of Alternaria was identified, of which, Alternaria alternata (Fries) Keissler was by far the commonest, representing 71.3% of all colonies.
This work deals with a study of the changes observed throughout the four seasons of the year concerning the number of fungi which can be found in the atmosphere of Barcelona. The results obtained will bring us to the conclusion that during the autumn and winter months the number of conidia per m3 is greater than in spring and summer. This observation would confirm the fact that generally speaking in autumn and winter, temperature decreases and humidity increases, while the opposite occurs in spring and summer. These phenomena would be directly related to our findings where we have established that an increase in temperature implies a reduction on the airborne fungi, while the remaining climatic factors taken into account would indicate an increase in the total fungal population. The same relation - phenomena were observed for the strains of the genus Cladosporium, Penicillium, Aureobasidium, Aspergillus and Alternaria, though with some modifications in the three later.
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