Testing of In Vitro Susceptibility of Neisseria gonorrhoeae to Azithromycin: Comparison of Disk Diffusion and Reference Agar Dilution Methods.

Azithromycin in combination with ceftriaxone is recommended as the first-line treatment for uncomplicated gonorrhea in many countries. Therefore, monitoring of azithromycin susceptibility of Neisseria gonorrhoeae isolates is essential. In 2019, the Clinical and Laboratory Standards Institute (CLSI) listed the MIC breakpoint for a susceptible-only category to azithromycin, but breakpoints for disk diffusion are not yet available. In this study, we evaluated the usefulness of disk diffusion for testing the susceptibility of N. gonorrhoeae isolates to azithromycin. A total of 189 clinical isolates susceptible and nonsusceptible to azithromycin were used. Agar dilution MICs were correlated with inhibition zone diameters of azithromycin disks (15-µg) manufactured by BBL and Oxoid. In addition, an interlaboratory study involving two clinical microbiology laboratories was conducted. There was a strong correlation between disk diffusion and agar dilution for BBL disks (r = -0.74; P < 0.001) and Oxoid disks (r = -0.75; P < 0.001). Using a zone diameter breakpoint of ≥27 mm (susceptible) and ≤26 mm (nonsusceptible) yielded good separation between susceptible and nonsusceptible isolates and the least number of discrepancies. Compared to agar dilution, disk diffusion showed high agreement and kappa values of 95.2% and 0.899 (P < 0.001) for BBL disks and 96.8% and 0.933 (P < 0.001) for Oxoid disks, respectively. Major and very major discrepancies were observed in isolates with azithromycin MICs (1 and 2 µg/ml, respectively) near to the breakpoint. These data illustrate that disk diffusion could be a reliable method in clinical laboratories to test susceptibility to azithromycin in N. gonorrhoeae isolates.

Coaxial Spinning of All-Cellulose Systems for Enhanced Toughness: Filaments of Oxidized Nanofibrils Sheathed in Cellulose II Regenerated from a Protic Ionic Liquid.

Hydrogels of TEMPO-oxidized nanocellulose were stabilized for dry-jet wet spinning using a shell of cellulose dissolved in 1,5-diazabicyclo[4.3.0]non-5-enium propionate ([DBNH][CO2Et]), a protic ionic liquid (PIL). Coagulation in an acidic water bath resulted in continuous core-shell filaments (CSFs) that were tough and flexible with an average dry (and wet) toughness of ∼11 (2) MJ·m-3 and elongation of ∼9 (14) %. The CSF morphology, chemical composition, thermal stability, crystallinity, and bacterial activity were assessed using scanning electron microscopy with energy-dispersive X-ray spectroscopy, liquid-state nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, pyrolysis gas chromatography-mass spectrometry, wide-angle X-ray scattering, and bacterial cell culturing, respectively. The coaxial wet spinning yields PIL-free systems carrying on the surface the cellulose II polymorph, which not only enhances the toughness of the filaments but facilities their functionalization.

Genome-based epidemiology and antimicrobial resistance determinants of Neisseria gonorrhoeae isolates with decreased susceptibility and resistance to extended-spectrum cephalosporins in Argentina in 2011-16.

OBJECTIVES: Our aim was to describe the molecular epidemiology and antimicrobial resistance determinants of isolates of Neisseria gonorrhoeae with decreased susceptibility and resistance to extended-spectrum cephalosporins (ESCs) in Argentina in 2011-16. METHODS: Gonococcal isolates (n=158) with decreased susceptibility and resistance to ESCs collected in 2011-16 across Argentina were subjected to WGS and antimicrobial susceptibility testing for six antimicrobials. RESULTS: In total, 50% of the isolates were resistant to cefixime, 1.9% were resistant to ceftriaxone, 37.3% were resistant to azithromycin and 63.9% of the isolates showed an MDR phenotype. Resistance and decreased susceptibility to ESCs was mainly associated with isolates possessing the mosaic penA-34.001, in combination with an mtrR promoter A deletion, and PorB1b amino acid substitutions G120K/A121N. Phylogenetic analysis revealed two main clades of circulating strains, which were associated with the N. gonorrhoeae multiantigen sequence typing (NG-MAST) ST1407 and closely related STs, and characterized by a high prevalence rate, wide geographical distribution and temporal persistence. CONCLUSIONS: N. gonorrhoeae isolates with decreased susceptibility and resistance to ESCs in Argentina have emerged and rapidly spread mainly due to two clonal expansions after importation of one or two strains, which are associated with the international MDR NG-MAST ST1407 clone. The identification of the geographical dissemination and characteristics of these predominant clones may help to focus action plans and public health policies to control the spread of ESC resistance in Argentina. Dual antimicrobial therapy (ceftriaxone plus azithromycin) for gonorrhoea needs to be considered in Argentina.

Use of Whole Genome Sequencing for the Molecular Comparison of Neisseria gonorrhoeae Isolates With Decreased Susceptibility to Extended Spectrum Cephalosporins From 2 Geographically Different Regions in America.

BACKGROUND: Neisseria gonorrhoeae isolates with reduced susceptibility or resistance to the recommended first-line antimicrobial therapy have been described in several countries. The purpose of this study was to use genome analyses to compare the molecular characteristics of N. gonorrhoeae isolates with decreased susceptibility to extended-spectrum cephalosporin from Ontario, Canada, and Argentina. METHODS: A total of 128 N. gonorrhoeae isolates, collected in 2015, were included. The susceptibility to penicillin G, tetracycline, ciprofloxacin, cefixime, ceftriaxone, and azithromycin was determined using the agar dilution method. Isolates were subjected to whole genome sequencing, and an in silico analysis was performed to identify antimicrobial resistance determinants and for genotyping. RESULTS: Decreased susceptibility to extended-spectrum cephalosporin was mainly associated with penA mosaic allele 34.001, together with an mtrR promoter A deletion and porB1b alterations G120K/A121N. N. gonorrhoeae multiantigen sequence typing ST1407 or closely related genotypes were identified circulating in both regions. CONCLUSIONS: An international multi-drug resistant clone of N. gonorrhoeae was associated with decreased susceptibility to extended-spectrum cephalosporin (ESC) in 2 different regions in America. Evidence of clonal dissemination of the organism in some regions suggests that the strength of surveillance programs and establishment of collaborative projects are essential.

Emergence and Spread of Neisseria gonorrhoeae Isolates With Decreased Susceptibility to Extended-Spectrum Cephalosporins in Argentina, 2009 to 2013.

BACKGROUND: The emergence of Neisseria gonorrhoeae strains with decreased susceptibility to cephalosporins represents a major concern globally. The aim of this study was to examine the phenotypic and molecular characteristics of N. gonorrhoeae isolates with decreased susceptibility to ceftriaxone and cefixime in Argentina. METHODS: A total of 1987 isolates were collected during 2009 and 2013. The susceptibility to penicillin G, tetracycline, ciprofloxacin, cefixime, ceftriaxone, and azithromycin was determined using the agar dilution method. The major extended-spectrum cephalosporin resistance determinants (penA, mtrR, and porB1b) were sequenced in 42 N. gonorrhoeae isolates that showed decreased susceptibility to ceftriaxone (minimum inhibitory concentration [MIC], 0.06-0.125 mg/L) and cefixime (MIC, 0.125-0.25 mg/L). Genotyping by N. gonorrhoeae multiantigen sequence typing (NG-MAST) was performed. RESULTS: Between 2009 and 2013, there was a shift in the modal MICs for ceftriaxone. Among the 42 isolates exhibiting decreased susceptibility to ceftriaxone and cefixime, 95.2% were resistant to penicillin G, 95.2% to tetracycline, 97.6% to ciprofloxacin, and 33.3% to azithromycin. Thirty-five (83.3%) of the 42 isolates had a mosaic penA allele XXXIV, which has been previously associated with resistance to ceftriaxone and cefixime as well as treatment failures. The isolates that contained the mosaic penicillin-binding protein 2 (PBP2) XXXIV were associated with NG-MAST ST1407 or closely related genotypes. CONCLUSIONS: In Argentina, N. gonorrhoeae isolates with decreased susceptibility to cefixime and ceftriaxone have now emerged, mostly due to the introduction of the internationally spread multidrug-resistant NG-MAST ST1407.

Prevalence of bla TEM-220 gene in Penicillinase-producing Neisseria gonorrhoeae strains carrying Toronto/Rio plasmid in Argentina, 2002 - 2011.

BACKGROUND: Penicillinase-producing Neisseria gonorroheae (PPNG) was first isolated in 1976. PPNG strains carrying bla TEM-1 and bla TEM-135 gene have been described in different countries. Recently, a novel bla TEM-220 allele was detected in PPNG isolates carrying Toronto/Rio plasmid. The prevalence and characteristics of TEM-220 strains worldwide are unknown, and therefore, it needs to be studied. The purpose of this study was to detect bla TEM-220 gene in PPNG strains possessing Toronto/Rio plasmid over a period of ten years in Argentina, and to evaluate the proportion of isolates producing non-TEM-220 containing the T539C substitution in the bla TEM allele. METHODS: One hundred and fifty one PPNG isolates carrying Toronto/Rio plasmid were studied between 2002 and 2011. A mismatch amplification mutation assay (MAMA) PCR was used to identify the T539C substitution in the bla TEM allele and a MAMA-PCR protocol was developed to detect the G547A substitution in the bla TEM-220. The reference agar dilution method of the Clinical and Laboratory Standard Institute (CLSI) was used for susceptibility testing to five ß-lactams antibiotics, ciprofloxacin, tetracycline and azithromycin. In all TEM-220-producing isolates, the whole bla TEM gene was sequenced and the isolates were typed using N. gonorroheae multiantigen sequence typing (NG-MAST). RESULTS: MAMA PCR successfully identified the G547A substitution in the bla TEM-220 allele. The proportion of isolates that possessed the bla TEM-220 allele was 2.6 %, and 93.2 % MAMA TEM-220 PCR-negative isolates showed the T539C substitution in the bla TEM gene. No differences in the susceptibility to five beta-lactam antibiotics tested were observed in PPNG isolates TEM-220-producing and PPNG isolates carrying the T539C substitution in the bla TEM gene. All TEM-220 isolates were indistinguishable by NG-MAST. CONCLUSION: This is the first study which shows the prevalence of bla TEM-220 in N. gonorrhoeae isolates carrying Toronto/Rio plasmid in Argentina. Although the bla TEM-220 allele does not appear to be associated with an extended spectrum beta-lactamase (ESBL) phenotype of resistance, a single nucleotide polymorphism added to the bla TEM-220 or bla TEM containing the T539C substitution could lead to the emergence of ESBL. Thus, it is imperative to investigate in surveillance programs, not only the plasmid type in PPNG isolates and the bla TEM allele associated, but phenotypical characteristics and geographical distribution of isolates.

Quorum sensing activity and control of yeast-mycelium dimorphism in Ophiostoma floccosum.

Quorum sensing (QS) activity in Ophiostoma fungi has not been described. We have examined the growth conditions on the control of dimorphism in Ophiostoma floccosum, an attractive biocontrol agent against blue-stain fungi, and its relationship with QS activity. In a defined culture medium with L-proline as the N source, a high inoculum size (10(7) c.f.u. ml(-1)) was the principal factor that promoted yeast-like growth. Inoculum size effect can be explained by the secretion of a QS molecule(s) (QSMs) responsible for inducing yeast morphology. QSM candidates were extracted from spent medium and their structure was determined by GC-MS. Three cyclic sesquiterpenes were found. The most abundant molecule, and therefore the principal candidate to be the QSM responsible for yeast growth of O. floccosum, was 1,1,4a-trimethyl-5,6-dimethylene-decalin (C15H24). Other two compounds were also detected.

White rot Basidiomycetes isolated from Chiloé National Park in Los Lagos region, Chile.

Wood decomposition is an important component in forest ecosystems but information about the diversity of fungi causing decay is lacking. This is especially true for the temperate rain forests in Chile. These investigations show results of a biodiversity study of white-rot fungi in wood obtained from Chiloé National Park in Los Lagos region, Chile. Culturing from white-rotted wood followed by sequencing of the complete internal transcribed spacer region of the ribosomal DNA (rDNA) or partial large subunit region of the rDNA, identified 12 different species in the Basidiomycota. All of these fungi were characterized as white rot fungi and were identified with a BLAST match of 97 % or greater to sequences in the GenBank database. Fungi obtained were species of Phlebia, Mycoacia, Hyphodontia, Bjerkandera, Phanerochaete, Stereum, Trametes, and Ceriporiopsis. This report identifies for the first time in Chile the species Ceriporiopsis subvermispora, Hyphodontia radula, Phlebia radiata, Phanerochaete affinis, Peniophora cinerea, Stereum gausapatum, Phlebia setulosa and Phanerochaete sordida. Scanning electron microscopy was used to characterize the type of decay caused by the fungi that were isolated and a combination of selective lignin degraders and simultaneous white rot fungi were found. Fungi that cause a selective degradation of lignin are of interest for bioprocessing technologies that require modification or degradation of lignin without cellulose removal.

[Neisseria gonorrhoeae identification. Usefulness of the Vitek 2C NH card]. / Identificación de Neisseria gonorrhoeae. Utilidad de la tarjeta 2 NH del sistema Vitek 2C.

A total of 115 unique clinical isolates of Neisseria gonorrhoeae and 54 strains of other genera and species included in the database of the NH card were tested by the Vitek 2C System (bioMèrieux, Marcy L'Etoile, Francia). The gonoccocal isolates had been previously identified by conventional biochemical tests and by the latex agglutination test with monoclonal antibodies using the Phadebact Monoclonal GC Test (Bactus AB, Sweden). The NH card correctly identified 111 (96.5 %) strains of 115 isolates; one strain was identified with low discriminatory power (0.86 %), one (0.86 %) was misidentified (as Neisseria meningitidis) whereas the other two (1.7 %) remained unidentified. The NH card for N. gonorrhoeae identification provided 100 % specificity. The results were available within 6 hours. The NH card could be considered a reliable and useful tool for routine use in Neisseria gonorrhoeae identification.

Screening and Identification of Coastal Chilean Thraustochytrids for Arachidonic Acid Production: Biotechnological Potential of Ulkenia visurgensis Lng2-Strain.

Thraustochytrids are unicellular heterotrophic marine protists that have been described as producing a high content of polyunsaturated fatty acids (PUFAs). Among them, arachidonic acid (ARA) stands out as a precursor of several mediators of pivotal importance for the immune system. However, the biotechnological potential of thraustochytrids for ARA production has not been developed. The objective of this study is to isolate and identify native strains from different Chilean coastal environments and evaluate in vitro the effect of culture parameters such as C/N ratio (19 and 33) and temperature (15 °C and 23 °C) on biomass production and arachidonic acid content. A total of nine strains were identified and classified into four genera of the Thraustochitridae family. The Lng2 strain with 99% identity belongs to the species Ulkenia visurgenis and was the most prominent one for ARA production. Temperature had an effect on the PUFA profile but not on the ARA content nor on the biomass yield. Additionally, the C/N ratio has been identified as a key parameter. The ARA productivity increased by 92% (from 0.6 to 8.3 ARA mg/g-DW) and its total biomass by 62.7% (from 1.9 to 5.1 g/L) at a high C/N ratio (33) as compared to the control.

Relationship between Structural Characteristics of Cellulose Nanocrystals Obtained from Kraft Pulp.

Kraft pulp cellulose was hydrolyzed using sulfuric acid, under different thermophysical conditions of temperature, time, pulp concentration, and sonication time. The experimental design revealed the effect of these conditions and their interaction on the hydrolysis yield obtained. In addition, the top five cellulose nanocrystals (CNCs) yields from this experiment design were analyzed. The results obtained indicated that CNCs possess a morphology that can be described as individualized rod particles, with average diameters less than 50 nm and different size distribution. In the analysis of CNCs features, significant Pearson correlations were established between the crystallinity of the CNC, CNC yield, and interplanar crystallites distance (Δd/d). The thermogravimetric (DTG) profiles exhibited two CNCs degradation stages, where the second stage CNCs degradation showed a significative correlation with CNC sulfur content. In our analysis, the crystallographic parameters exhibited a correlation with the mechanical behavior of the CNC, since the potential variation between the distances of the crystalline planes is related to the stress and deformation present in the crystallites of CNCs. This study provides new knowledge regarding CNCs, further enhancing information for CNC-based industries and the processability of CNCs for the development of new materials.

Emergence of high level azithromycin-resistant Neisseria gonorrhoeae strain isolated in Argentina.

One Neisseria gonorrhoeae strains highly resistant to azithromycin AzHLR (MIC >2048 mg/L) was isolated in Argentina in 2001 and it has been characterized by N. gonorrhoeae multiantigen sequence typing (NG-MAST) as ST696, suggesting a different event to other isolates in Europe. Neither, mtrR mutations or presence of mef gene were detected.

Resistencia antibiótica y aspectos clínicos de Neisseria gonorrhoeae anorrectal en un hospital de CABA, Argentina / Antimicrobial resistance and clinical aspects in anorectal Neisseria gonorrhoeae in a hospital in CABA, Argentina

La infección por Neisseria gonorrhoeae (NG) es considerada de alta prioridad en salud pública, por su capacidad para desarrollar resistencia a la mayoría de los antibióticos empleados para tratarla. La presentación anorrectal suele ser asintomática y frecuente en hombres que tienen sexo con hombres (HSH). En Argentina, se recomienda terapia antibiótica dual (ceftriaxona+azitromicina/doxiciclina) como primera línea empírica. Este estudio observacional y retrospectivo se realizó para evaluar el porcentaje de positividad de NG anorrectal, el perfil de sensibilidad a penicilina, tetraciclina, ciprofloxacina, ceftriaxona, cefixima y azitromicina, así como los aspectos clínicos-epidemiológicos de los pacientes atendidos entre 20/10/2015 y 20/03/2020 en consultorios coloproctológicos de un hospital público. Se detectaron 55/436 hisopados rectales positivos para NG (13%). El 95% era HSH y 71%, VIH+. En 18/55 NG fue la única infección. Las co-infecciones más frecuentes: HPV (38%) y C. trachomatis (35%). La sensibilidad a cefalosporinas de espectro extendido (CEE) y a azitromicina fueron 100% y 98%, respectivamente. Se observó la emergencia local de los primeros cinco aislamientos de NG anorrectal con sensibilidad reducida (SR) a CEE, el primer aislamiento con categoría no-sensible a azitromicina y otro con SR a azitromicina concomitantemente con SR a CEE. Aunque el uso de terapia empírica dual sigue siendo adecuado para nuestra institución, se observó la emergencia de aislamientos con SR y NS a las drogas de primera línea, evidenciando la importancia de la vigilancia epidemiológica a nivel local para definir los tratamientos empíricos.

Neisseria gonorrhoeae (NG) infection is considered a high public health priority because of its ability to develop resistance to most of the antibiotics used to treat it.The anorectal presentation is generally asymptomatic and frequent in men who have sex with men (MSM). In Argentina, dual therapy (ceftriaxone+azithromycin/doxycycline) is recommended as first line empiric therapy.This observational and retrospective study was conducted to evaluate the percentage of anorectal NG positivity, the susceptibility profile to penicillin, tetracycline, ciprofloxacin, ceftriaxone, cefixime and azithromycin, as well as the clinical-epidemiological aspects of patients attended between 20/10/2015 and 20/03/2020 in coloproctology of a public hospital.We detected 55/436 positive rectal swabs for NG (13%). 95% were MSM and 71% were PLHIV. In 18/55 NG was the only infection. The most frequent co-infections: HPV (38%) and C. trachomatis (35%).Susceptibility to extended-spectrum cephalosporins (ESCs) and azithromycin was 100% and 98%, respectively. Local emergence of the first five anorectal NG isolates with decreased susceptibility (DS) to ESCs, the first isolate with nonsusceptible category to azithromycin and another with DS to azithromycin concomitantly with DS to ESCs were observed.Although the use of dual empirical therapy continues to be adequate for our institution, the emergence of isolates with DS and NS to first-line drugs was observed, evidencing the importance of epidemiological surveillance at the local level to define empirical treatments

Comparison of disk diffusion and agar dilution methods for gentamicin susceptibility testing of Neisseria gonorrhoeae.

Gentamicin is a promising antibiotic for the treatment of multidrug-resistant gonorrhea. The aim of this study was to analyze the suitability and reliably of disk diffusion to monitor the susceptibility to gentamicin. We studied 237 Neisseria gonorrhoeae isolates obtained in 2013 and 2015. Reference MICs were correlated with inhibition zone diameters (in millimeters) of gentamicin 10 µg disks manufactured by BBL and Oxoid. The Pearson correlation between disk diffusion and agar dilution was r = -.68 (P < 0.001) for BBL disk and r = -.71 (P < 0.001) for Oxoid disk. No very major or major discrepancies were detected. However, a high percentage of minor discrepancies was observed (44.7%, BBL disk) and (21.9%, Oxoid disk). By adjusting the susceptible breakpoint to S ≥ 17 mm, the minor discrepancies rate was reduced to 19.4% (BBL disk) and 10.1% (Oxoid disk). The disk diffusion may be a screening method in clinical laboratories to detect the gentamicin susceptibility of N. gonorrhoeae.

Isolation and Characterization of Cellulose Nanocrystals from Rejected Fibers Originated in the Kraft Pulping Process.

In the final process of the bleached kraft pulp there are some cellulose fibers that are separated from the main fibers stream; these fibers are rejected and considered as a low quality fibers, these fibers are known as rejected fiber (RF). In the present work the potential use of these fibers for Cellulose Nanocrystals (CNCs) synthesis was studied. The physical and chemical properties of synthesized CNCs were characterized through different techniques such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), and Thermogravimetric Analysis (TGA). Results demonstrate the feasibility of CNCs synthesis with a yield of 28.1% and 36.9%, and crystallinity of 73.5% and 82.7%. Finally, the morphology and synthesis conditions suggest that this industrial reject fiber (RF) could be used as a source for the CNCs production, thus adding value to the kraft process and opening new possibilities for innovation in the pulp industry.

Infección por neisseria gonorrhoeaey fenotipos de resistencia antimicrobiana,Mar del Plata, 2005-2010 / Neisseria gonorrhoeae infection and phenotypes of antimicrobial resistance, Mar del Plata, 2005-2010 / Infecção por Neisseria gonorrhoeae e fenótipos de resistência antimicrobiana, Mar del Plata, 2005-2010

Se realizó un estudio epidemiológico de tipo descriptivo retrospectivo, para determinar la tasa de infección por Neisseria gonorrhoeae y sus fenotipos de resistencia a los antimicrobianos, en 666 pacientes adultos de ambos sexos que asistieron al servicio al Servicio de ITS del Instituto Nacional de Epidemiología "Dr. Juan H. Jara"- ANLIS "Dr. Carlos G. Malbrán", de la ciudad de Mar del Plata, entre los años 2005-2010. Para el diagnóstico de infección por N. gonorrhoeae, las muestras fueron obtenidas por hisopados endocervicales e hisopados uretrales a varones y luego cultivadas. Los aislamientos fueron remitidos al Laboratorio Nacional de Referencia en ITS para completar el estudio de sensibilidad antimicrobiana. Se obtuvo una tasa de infección por N. gonorrhoeae del 12,2% [IC 95%: 9,83-14,95]. Los fenotipos de resistencia más prevalentes resultaron QRNG/CMRNG (resistencia a quinolonas conjuntamente con resistencia cromosómica a penicilina y tetraciclina), QRNG (resistencia a quinolonas), PPNG (cepa productora de penicilinasa) y CMTR (resistencia cromosómica a tetraciclina). En el marco de la vigilancia epidemiológica de las infecciones producidas por N. gonorrhoeae, el rol del laboratorio consiste no sólo en monitorear la incidencia de casos en la población sino también el perfil de resistencia a los antibióticos de uso terapéutico, a fin de controlar la enfermedad.

An epidemiological retrospective descriptive study was conducted in order to determine the rate of Neisseria gonorrhoeae infection and the antimicrobial resistance phenotypes in 666 adult patients of both sexes who attended the Sexually Transmitted Disease Service, at the National Institute of Epidemiology "Dr. Juan H. Jara"- ANLIS city of Mar del Plata, between the years 2005- 2010. For the diagnosis of N. gonorrhoeae infection, samples were obtained by endocervical swabs and urethral swabs in men. Microbiological growth on selective culture medium was identified using carbohydrate utilization. N. gonorrhoeae isolates were subsequently submitted to the National Reference Laboratory in STI for the study of antimicrobial susceptibility by determining the minimum inhibitory concentration. The N. gonorrhoeae infection rate was 12.2% [CI 95%: 9.83-14.95]. The most prevalent resistance phenotypes were QRNG/CMRNG (quinolone resistance in addition to chromosomal resistance to penicillin and tetracycline), QRNG (resistance to quinolone), PPNG (penicillinase producing strain) and CMTR (chromosomal resistance to tetracycline). As part of the epidemiological surveillance of infections by N. gonorrhoeae, the role of the laboratory is not only to monitor the incidence of cases in the population but also the antibiotic resistance profile for therapeutic use, in order to control the disease.

Um estudo epidemiológico de tipo descritivo retrospectivo foi realizado para determinar a taxa de infecção por Neisseria gonorrhoeae e seus fenótipos de resistência aos antimicrobianos em 666 pacientes adultos de ambos os sexos que compareceram no Serviço de ITS do Instituto Nacional de Epidemiología "Dr. Juan H. Jara, ANLIS "Dr. Carlos G. Malbrán" da cidade de Mar del Plata, entre os anos de 2005-2010. Para o diagnóstico de infecção por N. gonorrhoeae, as amostras foram obtidas por esfregaços endocervicais e esfregaços uretrais em homens e em seguida cultivadas. Os isolados foram encaminhados para o Laboratório Nacional de Referência em ITS para completar o estudo da sensibilidade antimicrobiana. Uma taxa de infecção de 12,2% em N. gonorrhoeae [IC 95%: 9,83-14,95] foi obtida. Os fenótipos de resistência mais prevalentes foram QRNG/CMRNG (resistência às quinolonas em conjunto com a resistência cromossômica à penicilina e tetraciclina), QRNG (resistência a quinolonas), PPNG (cepa produtora de penicilinase) e CMTR (resistência cromossômica à tetraciclina). Sob o controle epidemiológico das infecções produzidas por N. gonorrhoeae, o papel do laboratório é não só monitorar a incidência de casos na população, mas também o perfil de resistência aos antibióticos de uso terapêutico, visando a controlar a doença.

A screening method for detecting iron reducing wood-rot fungi.

A plate assay using the Fe(II) selective dye, ferrozine, for detecting wood-rot fungi with Fe(III) reductive abilities, was developed. The assay is fast, simple and, in most cases, more sensitive than the corresponding liquid medium test. The brown rot fungi, Gloeophyllum trabeum and Laetiporeus sulphureus, displayed higher iron reductive capabilities than white rot fungi, Trametes versicolor, Ganoderma australe and Ceriporiopsis subvermispora.

Identificación de Neisseria gonorrhoeae. Utilidad de la tarjeta 2 NH del sistema Vitek 2C / [Neisseria gonorrhoeae identification. Usefulness of the Vitek 2C NH card].

A total of 115 unique clinical isolates of Neisseria gonorrhoeae and 54 strains of other genera and species included in the database of the NH card were tested by the Vitek 2C System (bioMÞrieux, Marcy L’Etoile, Francia). The gonoccocal isolates had been previously identified by conventional biochemical tests and by the latex agglutination test with monoclonal antibodies using the Phadebact Monoclonal GC Test (Bactus AB, Sweden). The NH card correctly identified 111 (96.5

) strains of 115 isolates; one strain was identified with low discriminatory power (0.86

) was misidentified (as Neisseria meningitidis) whereas the other two (1.7

) remained unidentified. The NH card for N. gonorrhoeae identification provided 100

specificity. The results were available within 6 hours. The NH card could be considered a reliable and useful tool for routine use in Neisseria gonorrhoeae identification.