[Synthesis and regulation of flavor compounds derived from brewing yeast: Esters].
This article focuses on esters, responsible for the floral and fruity beer flavor. Its formation depends on various enzymes and factors such as the concentration of wort nutrients, the amount of dissolved oxygen and carbon dioxide, fermentation temperature and mainly the genetics of the yeast used. We provide information about how the esters originate and how is the impact of different fermentative parameters on the final concentrations of these compounds and the quality of the end product. PMID: 29627148 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - April 10, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Isolation of Aspergillus tritici from internal environment (Chile): Ecological and clinical scope].
Authors: Vieille Oyarzo P, Cruz Choappa R, Piontelli Laforet E Abstract Indoor environments provide important protective habitats for humans, who live or work in them most of the time. Many of these environments lack ventilation, which affects the composition of microbial communities, especially that of the fungal community. The aim of this study is to report the isolation of Aspergillus section Candidi from indoor environments of the School of Medicine at Universidad de Valparaiso, Chile, and identification through morpho-physiological and molecular approaches. Their ecological and clinical features were highlight...
Source: Revista Argentina de Microbiologia - April 4, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Monitoring the degradation capability of novel haloalkaliphilic tributyltin chloride (TBTCl) resistant bacteria from butyltin-polluted site.
Authors: Hassan HA, Dawah SE, El-Sheekh MM Abstract Tributyltin (TBT) is recognized as a major environmental problem at a global scale. Haloalkaliphilic tributyltin (TBT)-degrading bacteria may be a key factor in the remediation of TBT polluted sites. In this work, three haloalkaliphilic bacteria strains were isolated from a TBT-contaminated site in the Mediterranean Sea. After analysis of the 16S rRNA gene sequences the isolates were identified as Sphingobium sp. HS1, Stenotrophomonas chelatiphaga HS2 and Rhizobium borbori HS5. The optimal growth conditions for biodegradation of TBT by the three strains were pH 9 ...
Source: Revista Argentina de Microbiologia - April 3, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Usefulness of rapid urease test samples for molecular analysis of clarithromycin resistance in Helicobacter pylori.
In conclusion, the biopsy specimens used for the rapid urease test were suitable samples for clarithromycin resistance detection in patients infected with H. pylori, which became especially useful in cases where the number or size of the biopsies is limited. In addition, this is the first report of a molecular analysis for clarithromycin resistance performed directly from gastric biopsies in our region. PMID: 29602600 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - April 1, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Usefulness of local health reports to link the incidence rate of diarrhea with the quality of drinking water].
In this study, we analyzed the reports of the health care center located in Vaqueros (Salta, Argentina) over an 8-month period. Moreover, we determined the concentration of Escherichia coli and Giardia spp. cysts in samples from four different drinking water sources. A statistical relationship between water quality and cases of diarrhea could not be found. However, using an odds ratio calculation, it was possible to determine that one of the studied drinking water systems acts as a protection factor in cases of diarrhea. The present work provides useful information for planning preventive measures by the local health syste...
Source: Revista Argentina de Microbiologia - March 25, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Development and storage studies of high density macrocapsules containing Lactobacillus spp. strains as nutritional supplement in young calves.
Authors: Astesana DM, Zimmermann JA, Frizzo LS, Zbrun MV, Blajman JE, Berisvil AP, Romero-Scharpen A, Signorini ML, Rosmini MR, Soto LP Abstract The aim of this study was to evaluate different production methodologies of probiotic macrocapsules with high bacterial densities destined to lactating calves. Three types of capsules containing Lactobacillus casei DSPV318T and Lactobacillus plantarum DSPV354T were prepared from an overnight culture in whey medium: (1) mixing the culture with calcium alginate and then, reincubating the capsules in whey (RC); (2) concentrating the biomass by centrifugation and mixing the pe...
Source: Revista Argentina de Microbiologia - March 24, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Prevalence of Trichomonas vaginalis and Human papillomavirus in female sex workers in Central Veracruz, Mexico.
The objective of this study was to determine the prevalence of T. vaginalis and HPV infections in FSWs in the city of Orizaba, Veracruz, Mexico. Samples from 105 FSWs were obtained by cervical swab and analyzed. The identification of T. vaginalis and HPV was performed by molecular methods. HPV DNA was identified in 5.71% of the samples with the presence of HPV16, HPV18, and HPV58. A percentage of 25.7% samples were positive for T. vaginalis for optical microscopy and 23.8% for PCR. The results of the study indicate the need to incorporate more sensitive methods for the timely diagnosis of STIs as well as comprehensive heal...
Source: Revista Argentina de Microbiologia - March 21, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Susceptibility to β-lactams in β-hemolytic streptococci.
Susceptibility to β-lactams in β-hemolytic streptococci. Rev Argent Microbiol. 2018 Mar 13;: Authors: Bonofiglio L, Gagetti P, García Gabarrot G, Kaufman S, Mollerach M, Toresani I, Vigliarolo L, von Specht M, Lopardo HA Abstract Group A (GAS), B (GBS), C (GCS) and G (GGS) β-hemolytic streptococci are important human pathogens. They cause infections of different severity and frequency. Nowadays, after 70 years of use, penicillin is still universally active against GAS, GCS and GGS. However, therapeutic failures have been recorded in 2-28% of pharyngitis cases (median: 12%) attribu...
Source: Revista Argentina de Microbiologia - March 21, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Carbapenemases in Acinetobacter baumannii. Review of their dissemination in Latin America.
Authors: Rodríguez CH, Nastro M, Famiglietti A Abstract Carbapenem resistance in gram-negative bacteria by production of carbapenemases is one of the most challenging issues regarding healthcare worldwide. We review the epidemiology and prevalence of carbapenemases in carbapenem-resistant Acinetobacter baumannii isolates from Latin American countries. High resistance rates to antimicrobial agents, particularly to carbapenems, are observed in this region. OXA-23 is the most widely disseminated class D-carbapenemase; it is present in all the countries of the region and is frequently associated to endemic clone...
Source: Revista Argentina de Microbiologia - March 21, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Characterization of extraintestinal pathogenic Escherichia coli strains isolated from household dogs and cats in Buenos Aires, Argentina].
In this study we characterized 85 extraintestinal pathogenic isolates genetically isolated from canines and felines. We used the Clermont scheme that includes intestinal (A and B1) and extraintestinal (B2 and D) phylogroups, virulence markers (pap1-2, pap3-4, sfa, afa, hlyA, aer and cnf) and hybrid pathogens. A percentage of 69.4% of the isolates belonged to phylogroup A; 1.2% to phylogroup B1; 16.5% to phylogroup B2 and 12.9% to phylogroup D. The most commonly found gene was sfa (21/85), followed by pap1-2 and cnf (20/85) and pap3-4 (19/85). No hybrids were detected. Animal isolates should be studied due to the zoonotic p...
Source: Revista Argentina de Microbiologia - March 21, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Scientific communication and the social practice of writing].
Authors: Zawoznik M PMID: 29519325 [PubMed - in process] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - March 11, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Demodex genus: colonizing parasites of healthy people or mites associated with ocular pathology?]
Authors: Mongi F, Laconte L, Casero RD Abstract Demodex folliculorum and Demodex brevis are mites that are responsible for human demodicosis affecting skin and frequently linked to ocular diseasess. The aim of this work was to determine the association between Demodex sp. and eyelid and eyelash diseases and to establish the predisposing factors for acquiring this parasitic disease. Eyelashes from symptomatic and asymptomatic patients (n=72) between 9 and 82 years old were analyzed, where 53% were positive for Demodex sp., of which 66% manifested ocular symptoms and pathologies, blepharitis and dry eye being prevale...
Source: Revista Argentina de Microbiologia - February 12, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Comparison of the identification results of Candida species obtained by BD Phoenix ™ and Maldi-TOF (Bruker Microflex LT Biotyper 3.1).
Comparison of the identification results of Candida species obtained by BD Phoenix™ and Maldi-TOF (Bruker Microflex LT Biotyper 3.1). Rev Argent Microbiol. 2018 Feb 05;: Authors: Marucco AP, Minervini P, Snitman GV, Sorge A, Guelfand LI, Moral LL, Integrantes de la Red de Micología CABA Abstract In patients with invasive fungal infections, the accurate and rapid identification of the genus Candida is of utmost importance since antimycotic sensitivity is closely related to the species. The aim of the present study was to compare the identification results of species of the genus Candida obt...
Source: Revista Argentina de Microbiologia - February 10, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Effectiveness of Beauveria bassiana (Baubassil ®) on the common cattle tick Rhipicephalus microplus in the Department of Guajira, Colombia].
[Effectiveness of Beauveria bassiana (Baubassil®) on the common cattle tick Rhipicephalus microplus in the Department of Guajira, Colombia]. Rev Argent Microbiol. 2018 Feb 02;: Authors: Tofiño Rivera AP, Ortega Cuadros M, Pedraza Claros B, Perdomo Ayola SC, Moya Romero DC Abstract The effectiveness of Baubassil®(Beauveria bassiana) on the tick Rhipicephalus (Boophilus) microplus was evaluated. In the in vitro phase, the optimal germination temperature of the fungus was determined by microcultures at 25, 30 and 35°C and the mortality of ticks. In the field, in a randomized design, 30 ...
Source: Revista Argentina de Microbiologia - February 8, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Detection of Chlamydia abortus in bovine reproductive losses in the province of La Pampa, Argentina].
This study shows the first detection of Chlamydiaceae and C. abortus DNA on reproductive losses of bovine cattle in Argentina, and the described prevalence value (4.78%) should be taken as baseline value due to the type of samples analyzed. Detection of genetic material from Chlamydiaceae not matching any of the studied species could be due to intraspecies variants or local species not yet described. Further research on Chlamydia infections in bovine cattle in Argentina is imperative to describe their range, to analyze their economic and zoonotic implications and to make recommendations about prevention and control measure...
Source: Revista Argentina de Microbiologia - January 21, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Non reported spa types in our country in Staphylococcus aureus from adult patients of a school hospital, Santa Fe - Argentina].
Authors: Tomatis C, Baroni MR, Mendosa MA, Nagel A, Mollerach A, Alvarez C, Zurbriggen ML, Cristobal S, Segovia G, Méndez ELA Abstract Staphylococcus aureus is a pathogen associated a different kind of infection. Molecular markers are useful tools to study microbial epidemiology. Twenty two methicillin-resistant S. aureus (MRSA) and 23 methicillin-susceptible S. aureus (MSSA) were studied by mecA gene, SCCmec cassette, Panton Valentine leucocidin (PVL) and spa polymorphism. The clinical data patients were analyzed. MSSA was prevalent in samples different from skin and soft tissue (SST) and in hospitalized pa...
Source: Revista Argentina de Microbiologia - January 19, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Bioconversion of hemicellulosic materials into ethanol by yeast, Pichia kudriavzevii 2-KLP1, isolated from industrial waste.
Authors: Elahi A, Rehman A Abstract In the present work, a yeast strain Pichia kudriavzevii was identified on the basis of 18S rDNA, showing maximum growth at 30°C and pH 7.0. Among all the complex polysaccharides used, wheat bran proved to be the best substrate as indicated by the maximum growth of the yeast strain. The yeast isolate was capable of producing xylanase both intra- and extra-cellularly, the dominant form being extracellular. The maximum enzyme activity was determined at pH 5.0 and at 50°C. Na+, Mg2+ and Fe2+ presence caused a substantial increase in enzyme activity while a slight decrease (4....
Source: Revista Argentina de Microbiologia - January 19, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Detection and characterization of Shiga toxin-producing Escherichia coli in children treated at an inter-zonal pediatric hospital in the city of La Plata].
This study shows that STEC of different serotypes and genotypes circulate in the city of La Plata and surroundings. Despite the genetic diversity observed between the O157:H7 isolates, some were indistinguishable by the subtyping techniques used. PMID: 29336911 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - January 19, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Bartonella henselae: Serological evidence in pediatric patients with clinical suspicion of cat scratch disease].
The objective of this study was to analyze the serological evidence of B. henselae infection in pediatric patients that met the clinical/epidemiological criteria for suspected CSD. We studied 92 patients, who were categorized into four serological groups: 1) IgG (+)/IgM(+), 31,5% (n=29); 2) IgG (-)/IgM(+), 10,9% (n=10); 3) IgG (+)/IgM(-), 9,8% (n=9); 4) IgG (-)/IgM(-), 47,8% (n=44). These findings aim to promote future works for investigating the seroprevalence of Bartonella spp. in Argentina, which will allow us to know the importance of this zoonosis in our population and to evaluate new cut-off points of the technique. ...
Source: Revista Argentina de Microbiologia - January 19, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Serological study of brucellosis in Argentine Creole sheep.
This study showed that the total positive percentage of brucellosis due to B. ovis was 2.9%. Excluding the animals mixed with the Suffolk breed; seropositivity would be 0.6%. All animals tested negative for brucellosis caused by B. melitensis. PMID: 29310845 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - January 10, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Diseases and pests noxious to Pleurotus spp. mushroom crops.
Authors: Bellettini MB, Bellettini S, Fiorda FA, Pedro AC, Bach F, Fabela-Morón MF, Hoffmann-Ribani R Abstract The Pleurotus genus is one of most extensively studied white-rot fungi due to its exceptional ligninolytic properties. It is an edible mushroom that possesses biological effects, as it contains important bioactive molecules. It is a rich source of nutrients, particularly proteins, minerals as well as vitamins B, C and D. In basidiomycete fungi, intensive cultivations of edible mushrooms can often be affected by some bacterial, mold and virus diseases that rather frequently cause dramatic production ...
Source: Revista Argentina de Microbiologia - January 3, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Bacillus subtilis with endocellulase and exocellulase activities isolated in the thermophilic phase from composting with coffee residues.
Authors: Siu-Rodas Y, Calixto-Romo MLA, Guillén-Navarro K, Sánchez JE, Zamora-Briseño JA, Amaya-Delgado L Abstract The goal of this study was to isolate, select and characterize bacteria with cellulolytic activity from two different coffee residue composting piles, one of which had an internal temperature of 57°C and pH 5.5 and the other, a temperature of 61°C, and pH 9.3. Culture media were manipulated with carboxymethylcellulose and crystalline cellulose as sole carbon sources. The enzyme activity was assessed by hydrolysis halo formation, reducing sugar production and zymograms. Thre...
Source: Revista Argentina de Microbiologia - January 3, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Characterization of the genetic variability of field strains of Brucella canis isolated in Antioquia].
Authors: Vidal Arboleda JL, Ortiz Roman LF, Olivera Angel M Abstract Brucella canis is a facultative intracellular pathogen responsible for canine brucellosis, a zoonotic disease that affects canines, causing abortions and reproductive failure; and the production of non-specific symptoms in humans. In 2005 the presence of B. canis in Antioquia was demonstrated and the strains were identified as type 2. The sequencing of the genome of a field strain denoted Brucella canis str. Oliveri, showed species-specific indel events, which led us to investigate the genomic characteristics of the B. canis strain isolated and to...
Source: Revista Argentina de Microbiologia - December 29, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Characterization of Rhodococcus sp. A5wh isolated from a high altitude Andean lake to unravel the survival strategy under lithium stress.
Authors: Belfiore C, Curia MV, Farías ME Abstract Lithium (Li) is widely distributed in nature and has several industrial applications. The largest reserves of Li (over 85%) are in the so-called "triangle of lithium" that includes the Salar de Atacama in Chile, Salar de Uyuni in Bolivia and Salar del Hombre Muerto in Argentina. Recently, the use of microorganisms in metal recovery such as copper has increased; however, there is little information about the recovery of lithium. The strain Rhodococcus sp. A5wh used in this work was previously isolated from Laguna Azul. The assays revealed that this s...
Source: Revista Argentina de Microbiologia - December 15, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Temporal diversity dynamics of the arbuscular mycorrhizal fungi of Larrea tridentata (Sesse & Mocino ex DC) Coville in a semi-arid ecosystem].
[Temporal diversity dynamics of the arbuscular mycorrhizal fungi of Larrea tridentata (Sesse & Mocino ex DC) Coville in a semi-arid ecosystem]. Rev Argent Microbiol. 2017 Dec 06;: Authors: Hernández-Zamudio G, Sáenz-Mata J, Moreno-Reséndez A, Castañeda-Gaytán G, Ogaz A, Carballar-Hernández S, Hernández-Cuevas L Abstract Arbuscular mycorrhizal fungi (AMF) of arid and semiarid ecosystems are important for the development of plants that grow under biotic stress in wild or in agro-ecosystems. There is little information on the temporal diversity of these...
Source: Revista Argentina de Microbiologia - December 12, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Streptococcus agalactiae bacteremia in non-pregnant adult patients at two teaching hospitals.
Authors: Saad EJ, Baenas DF, Boisseau CS, García MJ, Núñez SA, Sanchez PE, Balderramo DC, Hernández D, Caeiro JP Abstract Streptococcus agalactiae or group B streptococcus (GBS) is a frequent pathogen in immunocompromised adults. The aim of this study was to determine the relative frequency, clinical presentation, antimicrobial susceptibility profile, and risk factors associated with GBS bacteremia in non-pregnant adult patients. We conducted a retrospective analysis of blood cultures performed in two hospitals between the years 2009-2013. From 1110 bacteremia episodes, 13 were caused by...
Source: Revista Argentina de Microbiologia - December 12, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

In vitro effect of Chrysosporium indicum and Chrysosporium keratinophylum on Toxocara canis eggs.
Authors: Bojanich MV, Basualdo JA, Giusiano G Abstract The degree of antagonism exercised by fungi on geohelminth development varies according to the morphological alterations caused by different fungal species. Saprophytic fungi may exert ovicidal or ovistatic effects. The aim of this study was to apply scanning electron microscopy (SEM) to observe the action of two soil saprophytic species of Chrysosporium (C. indicum and C. keratinophylum) on Toxocara canis eggs. The fungal strains to be tested were incubated for 28 days at 28°C in 2% water agar with a suspension of unembryonated T. canis eggs. A suspension ...
Source: Revista Argentina de Microbiologia - December 11, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Bovine respiratory syncytial virus seroprevalence and risk factors in feedlot cattle from C órdoba and Santa Fe, Argentina.
Bovine respiratory syncytial virus seroprevalence and risk factors in feedlot cattle from Córdoba and Santa Fe, Argentina. Rev Argent Microbiol. 2017 Nov 30;: Authors: Ferella A, Pérez Aguirreburualde MS, Margineda C, Aznar N, Sammarruco A, Dus Santos MJ, Mozgovoj M Abstract Bovine respiratory syncytial virus (BRSV) is one of the causative agents of respiratory disease in cattle all over the world, leading to important economic losses. The aim of this work was to determine the seroprevalence of BRSV in feedlot cattle of Argentina and the risk factors associated with the disease. Results s...
Source: Revista Argentina de Microbiologia - December 5, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Isolation of saprophytic Leptospira spp. from a selected environmental water source of Argentina.
Authors: Scialfa E, Grune S, Brihuega B, Aguirre P, Rivero M Abstract Ten Leptospira spp. strains were isolated from water samples from Nievas stream, Olavarría, Buenos Aires province (Argentina). The isolates showed the typical motility and morphology of the genus Leptospira under dark field microscopy, developing in liquid EMJH medium after eight days of incubation at 13°C and 30°C. All isolates were negative by the Multiple Locus Variable Number Tandem Repeat Analysis (MLVA). Molecular identification by 16S rRNA gene sequencing identified all isolates as nonpathogenic leptospires. Four isolates sh...
Source: Revista Argentina de Microbiologia - December 5, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Antimicrobial susceptibility in isolates of Streptococcus equi subsp. equi from Buenos Aires province, Argentina].
Authors: Bustos CP, Marfil MJ, Lanza NS, Guida N Abstract Streptococcus equi subsp. equi is the etiologic agent of strangles, an infectious disease affecting the upper respiratory tract and head and neck lymph nodes of equines. Routine antimicrobial therapy includes penicillin (PEN) as antibiotic of first choice. Streptococci are usually susceptible to PEN and only a few antimicrobial studies had been performed. The aim of this work was to study the antimicrobial susceptibility profile of S. equi from Buenos Aires, Argentina. Ninety-two isolates were studied by the single disk method to PEN, cefotaxime, erythromyci...
Source: Revista Argentina de Microbiologia - December 5, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Food mycology: ¿An emerging discipline?]
[Food mycology: ¿An emerging discipline?] Rev Argent Microbiol. 2017 Oct - Dec;49(4):303-304 Authors: Noemí Chulze S PMID: 29162231 [PubMed - in process] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - November 24, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Validation of the technique based on Dot blot for the detection of Cercospora kikuchii in soybean plants].
The objective was to validate this technique to guarantee the reliability of the results. For that purpose, 29 infected soybean plants and 31 healthy plants were processed, taking into account a 95% desired confidence level and a permissible error of 5%. The technique provided a diagnostic sensitivity of 93.3% and a diagnostic specificity of 96.7%. The efficiency was 95% and positive and negative predictive values were 96.6% and 93.5%, respectively. These results postulate it as a useful resource for the early detection of C. kikuchii in soybean plants. PMID: 29162301 [PubMed - as supplied by publisher] (Source: Revist...
Source: Revista Argentina de Microbiologia - November 24, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Native yeasts for alternative utilization of overripe mango pulp for ethanol production.
Authors: Buenrostro-Figueroa J, Tafolla-Arellano JC, Flores-Gallegos AC, Rodríguez-Herrera R, De la Garza-Toledo H, Aguilar CN Abstract Mango fruits (Mangifera indica L.) are highly perishable, causing postharvest losses and producing agroindustrial waste. In the present work, native yeasts were used to evaluate ethanol production in overripe mango pulp. The two isolated strains showed similar sequences in the 18S rDNA region corresponding to Kluyveromyces marxianus, being different to the data reported in the NCBI database. Values of up to 5% ethanol (w/v) were obtained at the end of fermentation, showing a...
Source: Revista Argentina de Microbiologia - November 24, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Molecular epidemiology and phylogenetic analysis of human papillomavirus infection in women with cervical lesions and cancer from the coastal region of Ecuador.
This study provides novel data on HPV epidemiology and evolution in Ecuador, which will be fundamental in the vaccine era. PMID: 29157596 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - November 22, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Glutamate dehydrogenase. Its diagnostic value in Clostridioides difficile diarrhea].
Authors: Vaustat D, Rollet R Abstract Clostridioides difficile is the main etiological agent of diarrhea associated with health care, it produces toxins and glutamate dehydrogenase (GDH), an enzyme that is highly conserved in this species. Rapid diagnosis and effective treatment produce prompt improvement of the patient and subsequent control of the microorganism spread. There are several techniques whose results are interpreted in the context of algorithms. However, the optimal diagnostic method is yet unknown. The performance of GDH as a screening test for the diagnosis of C. difficile diarrhea was assessed. Six ...
Source: Revista Argentina de Microbiologia - November 20, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Validation of a liquid chromatography/tandem mass spectrometry method for the detection of aflatoxin B1 residues in broiler liver.
Authors: Magnoli AP, González Pereyra ML, Monge MP, Cavaglieri LR, Chiacchiera SM Abstract Aflatoxin B1 is a carcinogenic and mutagenic mycotoxin produced mainly by Aspergillus flavus and Aspergillus parasiticus. It is the predominant mycotoxin found in raw materials used for the manufacture of broiler feeds. The aim of the present study was to develop a new and optimized method for the detection and quantification of aflatoxin B1 (AFB1) residues in broiler liver using solid phase extraction (SPE) clean-up and liquid chromatography-electrospray ionization/tandem mass spectrometry (LC-ESI-MS/MS) detection. Th...
Source: Revista Argentina de Microbiologia - November 18, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Scanning electron microscopic observations of early stages of interaction of Trichoderma harzianum, Gliocladium virens and Bacillus subtilis with Acaulospora colombiana.
Authors: Ortiz EM, Duchicela J, Debut A PMID: 29132715 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - November 15, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

A 14-20kDa protein binds to the upstream region of the phtM operon involved in the synthesis of phaseolotoxin in Pseudomonas syringae pv. phaseolicola NPS3121.
Authors: Álvarez-Morales A, Hernández-Morales A, Arvizu-Gómez JL Abstract Pseudomonas syringae pv. phaseolicola is a phytopathogenic bacterium in beans that produces a phytotoxin called phaseolotoxin, in whose synthesis a group of genes that belong to the "Pht cluster" are involved. This cluster comprises 23 genes arranged in 5 transcriptional units, two monocistronic (argK, phtL) and three polycistronic (phtA, phtD, phtM) operons, whose expression is increased at 18°C, correlating with the production of phaseolotoxin by the bacterium. So far, the regulatory mechanisms involved in...
Source: Revista Argentina de Microbiologia - November 15, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Production of a compost accelerator inoculant].
Authors: Medina Lara MS, Quintero Lizaola R, Espinosa Victoria D, Alarcón A, Etchevers Barra JD, Trinidad Santos A, Conde Martínez FV Abstract Composting was performed using a mixture of ovine manure and straw. Inoculum was extracted at five different phases of the composting process (18, 23, 28, 33 and 38 days after the start of the composting process) and its effect on reducing biotransformation time was evaluated in the composted ovine manure. The samples were preserved in a deep freezer, then lyophilized to obtain the inoculum, 50g of which was added to each treatment in the second experimental ph...
Source: Revista Argentina de Microbiologia - November 7, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Quercetin attenuates Staphylococcus aureus virulence by reducing alpha-toxin secretion].
This study shows that quercetin, a naturally occurring flavonoid, inhibits hemolytic activity in a dose-dependent manner and reduces alpha toxin secretion in culture supernatants of methicillin-sensitive and methicillin-resistant S.aureus. Furthermore, quercetin significantly prevents damage to human alveolar cells when co-cultured with S.aureus. Our results suggest that quercetin can reduce S.aureus virulence by affecting alpha-toxin secretion. PMID: 29100712 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - November 5, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Compatibility of chemical insecticides and entomopathogenic fungi for control of soybean defoliating pest, Rachiplusia nu.
Authors: Pelizza SA, Schalamuk S, Simón MR, Stenglein SA, Pacheco-Marino SG, Scorsetti AC Abstract Rachiplusia nu (Guenée) (Lepidoptera: Noctuidae) is one of the major lepidopteran pests defoliating soybeans (Glycine max Merrill) in Argentina. The combined use of chemical insecticides and entomopathogenic fungi is a promising pest-control option to minimize adverse chemical effects. In this work, we evaluated the interactions between five insecticides-two being considered biorational-and five fungal entomopathogenic strains under laboratory conditions in order to determine the possible usefulness of c...
Source: Revista Argentina de Microbiologia - October 29, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Yeast microbiota in artisanal cheeses from Corrientes, Argentina].
Authors: Cardozo MC, Fusco ÁJV, Carrasco MS Abstract The artisanal cheese from Corrientes (from the Spanish acronym QAC-Queso Artesanal de Corrientes/Artisanal Cheese from Corrientes) is a soft cheese elaborated with raw cow milk and an artisanal coagulant agent. Lactic bacteria contitute the main flora of this cheese although yeasts are also present in high quantities as secondary microbiota and might play a relevant role in cheese ripening. The aim of this work was to evaluate yeast occurrence during QAC elaboration and ripening, and the effect of seasonal variation. Yeasts were isolated and purified from ...
Source: Revista Argentina de Microbiologia - October 29, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Differentiation of pathogenic leptospires spp by PCR of ligB gene and sequencing].
The objective of this work was to develop a molecular technique to differentiate pathogenic Leptospira spp. A region of adhesin ligB, present only in the pathogenic species was amplified by PCR and sequenced. ligBRpet and ligBFpet primers were used, which amplified the target DNA from pathogenic L. interrogans reference strains serovars Pomona strain Pomona, Canicola strain Hond Utrecht IV, Copenhageni strain M 20, Wolffi strain 3705, Pyrogenes strain Salinem, Hardjo strain Hardjoprajitmo, L. borgpetersenii serovar Castellonis strain Castellon 3 and 4 pathogenic strains isolated from bovines, pigs, rats and opossums. L. bi...
Source: Revista Argentina de Microbiologia - October 28, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Persistence of the same genetic type of Mycoplasma hyopneumoniae in a closed herd for at least two years.
Authors: Rebaque F, Camacho P, Parada J, Lucchesi P, Ambrogi A, Tamiozzo P Abstract Two cross-sectional studies were carried out in 2013 and 2015 monitoring for Mycoplasma hyopneumoniae presence in a swine farm. In these studies, the genetic diversity of M. hyopneumoniae was assessed in clinical specimens using a Multiple Locus Variable-number tandem repeat Analysis (MLVA) targeting P97 R1, P146 R3 and H4 loci. The samples from August 2015 showed the MLVA profile prevalent in June 2013, therefore it can be concluded that a same genetic type of M. hyopneumoniae can persist for at least two years in a closed herd. In...
Source: Revista Argentina de Microbiologia - October 28, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[First description of Sclerotium coffeicola on African mahogany in Mexico].
Authors: Pérez-Vera OA, Cibrián-Tovar D, T-Hanlin R Abstract A foliar disease was detected in the commercial plantation of Khaya senegalensis with three years of age in Huimanguillo, Tabasco, Mexico. Through the morphological and molecular characterization and the compliance of the Koch's postulates, it was concluded that the causal agent corresponds to the fungus Sclerotium coffeicola. This is the first report of S. coffeicola causing leaf spot on African mahogany in Mexico. PMID: 29054548 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - October 22, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Growth and photochemical efficiency of photosystem ii in seedlings of two varieties of Capsicum annuum L. inoculated with rhizobacteria and arbuscular mycorrhizal fungi].
Authors: Angulo-Castro A, Ferrera-Cerrato R, Alarcón A, Almaraz-Suárez JJ, Delgadillo-Martínez J, Jiménez-Fernández M, García-Barradas O Abstract Plant growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) are a biological alternative for the sustainable management of Capsicum annuum L. This research work evaluated the effects of both PGPR and AMF on bell pepper and jalapeno pepper plants. Five bacterial strains isolated from several locations in Estado de Mexico were used: [P61 (Pseudomonas tolaasii), A46 (P. tolaasii), R44 (Bacillus pumilus), BSP1.1...
Source: Revista Argentina de Microbiologia - October 22, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[MLVA analysis and virulence profile of community-acquired methicillin-resistant Staphylococcus aureus causing infections in Paraguayan children].
This study revealed the presence of CA-MRSA harbouring SCCmeciv with high genetic diversity, providing information not available in our country. PMID: 29054550 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - October 22, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Mycoplasma hominis bacteremia. An underestimated etiological agent].
We describe a case of bacteremia caused by M. hominis in a previously healthy woman after uterine curettage due to incomplete abortion. M. hominis could be an underestimated cause of bacteremia in immunocompetent patients. Mycoplasma organisms have fastidious growth requirements, are often difficult to culture on a cell-free medium and have no cell wall. The conventional method for detection may fail. This is the first report of M. hominis isolation from a positive automated blood culture (BD BACTEC, USA). PMID: 29054551 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - October 22, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Biofilm-forming capacity of blood-borne Candida albicans strains and effects of antifungal agents.
In conclusion, echinocandins were most effective against formed biofilms, while itraconazole was most effective for preventing biofilm formation. Standardized methods are needed for biofilm antifungal sensitivity tests when determining the treatment and prophylaxis of C. albicans infections. PMID: 28988900 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - October 12, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Detection of toxigenic Clostridioides [Clostridium] difficile: Usefulness of two commercially available enzyme immunoassays and a PCR assay on stool samples and stool isolates.
Authors: Legaria MC, Rollet R, Di Martino A, Castello L, Barberis C, Rossetti MA, Guardati MC, Fernández Canigia L, Carloni G, Litterio M, Rocchi M, Anchart EG, Trejo FM, Minnaard J, Klajn D, Predari SC Abstract The best laboratory diagnostic approach to detect Clostridioides [Clostridium] difficile infection (CDI) is a subject of ongoing debate. With the aim of evaluating four laboratory diagnostic methods, 250 unformed stools from patients with suspected CDI submitted to nine medical center laboratories from November 2010 to December 2011, were studied using: (1) an immunochromatographic rapid assay test t...
Source: Revista Argentina de Microbiologia - October 12, 2017 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research