Nanocristais de besifloxacino para o tratamento de conjuntivite bacteriana: preparação, caracterização físico-química e toxicidade / Besifloxacin nanocrystals for treating bacterial conjunctivitis: preparation, physicochemical characterization, and toxicity

A conjuntivite bacteriana tem significante impacto na Saúde Pública. Essa infecção representa mais de um terço das doenças oculares relatadas em âmbito global. É uma doença altamente contagiosa causada por variedade de bactérias aeróbias e anaeróbias. Diferentes antibióticos empregados no tratamento dessa doença têm apresentado elevada incidência de resistência bacteriana. Dentre os antibióticos de última geração, destaca-se o besifloxacino, antibiótico de quarta geração da classe das fluoroquinolonas, indicado exclusivamente para uso oftálmico tópico. Entretanto, esse fármaco possui baixa solubilidade em água, diminuindo sua biodisponibilidade. Tendo em vista superar esse desafio, foi proposta abordagem nanotecnológica para o desenvolvimento de nanocristais desse fármaco. A preparação de nanocristais de besifloxacino empregando moagem via úmida em escala reduzida foi promissora empregando tensoativo Povacoat®. O Diâmetro hidrodinâmico médio (DHM) da partícula foi de aproximadamente 550 nm, com índice de polidispersão (IP) menor que 0,2. Esse resultado permitiu aumentar a solubilidade de saturação em aproximadamente duas vezes em relação a matéria-prima, possibilitando aumentar a velocidade de dissolução desse fármaco e melhorar sua biodisponibilidade e segurança. Além disso, foi validado o método para quantificação do besifloxacino por CLAE, apresentando especificidade, linearidade no intervalo de 20 a 80µg/mL (r= 0,9996), precisão por repetibilidade (DPR= 1,20%, 0,84% e 0,39%), precisão intermediária (DPR= 0,94%) e exatidão 99,03%. Estudo de estabilidade acelerado (90 dias) na condição 40°C±2°C/75%UR±5%UR e estudo de estabilidade de acompanhamento (150 dias) na condição: 25°C ± 2°C / 60% UR ± 5% UR evidenciaram a estabilidade do teor no período avaliado. Ainda, a nanossuspensão de besifloxacino 0,6% m/m (nanocristais) na dose máxima (500 mg/kg) e o estabilizante Povacoat® (750 mg/kg) não apresentaram toxicidade em larvas de G. mellonella. A concentração inibitória mínima (CIM) para a formulação inovadora foi de 0,0960 µg/mL e 1,60 µg/mL frente a Staphylococcus aureus e Pseudomonas aeruginosa, respectivamente, confirmando eficácia in vitro

Bacterial conjunctivitis greatly impacts the population's health, presenting more than a third of eye diseases reported worldwide. It is an infection caused by various aerobic and anaerobic bacteria and is highly contagious. Therefore, it presents a high incidence of bacterial resistance to the antibiotics commonly used for treatment. Among the most recent antibiotics, besifloxacin is a fourth-generation fluoroquinolone antibiotic indicated exclusively for topical ophthalmic use. Due to its importance in treating bacterial conjunctivitis and its low solubility in the water, a nanotechnological approach was proposed to develop besifloxacin nanocrystals. The preparation of besifloxacin nanocrystals using small-scale wet milling was promising using Povacoat® surfactant. The particle's average hydrodynamic diameter (DHM) was approximately 550 nm, with a polydispersity index (IP) of less than 0.2. This result increased the saturation solubility approximately two times concerning the raw material, making it possible to increase the dissolution rate of this drug and improve its bioavailability and safety. In addition, the method for quantification of besifloxacin by HPLC was validated, presenting specificity, linearity in the range of 20 to 80µg/mL (r= 0.9996), precision by repeatability (DPR= 1.20%, 0.84% and 0.39%), intermediate precision (DPR= 0.94%) and accuracy 99.03%. Accelerated stability study (90 days) at 40°C±2°C/75%RH±5%RH condition and follow-up stability study (150 days) at 25°C ± 2°C / 60% RH ± condition 5% RH showed the stability of content in the evaluated period. Furthermore, the 0.6% besifloxacin nanosuspension (nanocrystals) at the maximum dose (500 mg/kg) and the Povacoat® stabilizer (750 mg/kg) did not show toxicity in G. mellonella larvae. The minimum inhibitory concentration (MIC) to innovative formulation was 0.0960 µg/mL and e 1.60 µg/mL against Staphylococcus aureus and Pseudomonas aeruginosa, respectively, confirming in vitro efficacy

Aerobic microbial taxa dominate deep subsurface cores from the Alberta oil sands.

Little is known about the microbial ecology of the subsurface oil sands in Northern Alberta, Canada. Biodegradation of low molecular weight hydrocarbons by indigenous microbes has enriched high molecular weight hydrocarbons, resulting in highly viscous bitumen. This extreme subsurface environment is further characterized by low nutrient availability and limited access to water, thus resulting in low microbial biomass. Improved DNA isolation protocols and increasingly sensitive sequencing methods have allowed an in-depth investigation of the microbial ecology of this unique subsurface environmental niche. Community analysis was performed on core samples (n = 62) that were retrieved from two adjacent sites located in the Athabasca Oil Sands at depths from 220 to 320 m below the surface. Microbial communities were dominated by aerobic taxa, including Pseudomonas and Acinetobacter. Only one core sample microbial community was dominated by anaerobic taxa, including the methanogen Methanoculleus, as well as Desulfomicrobium and Thauera. Although the temperature of the bitumen-containing subsurface is low (8°C), two core samples had high fractions of the potentially thermophilic taxon, Thermus. Predominance of aerobic taxa in the subsurface suggests the potential for in situ aerobic hydrocarbon degradation; however, more studies are required to determine the functional role of these taxa within this unique environment.

Longitudinal Analyses of Gut-Associated Bacterial Microbiota in Ulcerative Colitis Patients.

BACKGROUND: The normal colonic microbiota is associated with the etiology of ulcerative colitis (UC). Several bacterial species are associated with the initiation and amplification of disease process. However, the etiology and mechanism of UC are poorly understood. The present study aimed to investigate, characterize, and compare the main composition of the mucosa-associated intestinal microflora in colonoscopic biopsy specimens of UC and non-UC patients. METHODS: Aerobic and facultative-anaerobic mucosa-associated bacteria were isolated and diagnosed from colonoscopic biopsy specimens of 40 UC patients and 40 patients without UC. Patients were selected as control from the same centers and colonoscopy was carried out for other reasons (mainly colorectal screening). Isolation and characterization for aerobic and facultative-anaerobic intestinal bacteria were carried out by conventional culture techniques. DNA extraction from biopsies and polymerase chain reaction (PCR) amplification of bacterial 16S rRNA with gene-targeted and species-specific primers was performed for detection of anaerobic bacterial species. RESULTS: Several species of mucosa-associated aerobic and facultative anaerobic bacteria were found in biopsy specimens and there were no significant differences between UC patients and non-UC patients. Our investigation for detection of the anaerobic intestinal flora showed Faecalibacterium prausnitzii, Prevotella, and Peptostreptococcus productus were the predominant microflora in controls and have significant differences (P = 0.002, 0.025 and 0.039, respectively). CONCLUSION: This is the first investigation of the intestinal mucosa-associated microflora in patients with UC in Iran. These results, although limited by sample size, allow a better understanding of changes in mucosa-associated bacterial flora in these patients, showing that decrease of Faecalibacterium prausnitzii, Provetella, and Peptostreptococcus productus in the intestinal tract may translate into a reduction in the important role of this beneficial bacterial species, which can lead to reduced protection of the gut mucosa and UC development.

Phylogeny and genomics of SAUL, an enigmatic bacterial lineage frequently associated with marine sponges.

Many marine sponges contain dense and diverse communities of associated microorganisms. Members of the 'sponge-associated unclassified lineage' (SAUL) are frequently recorded from sponges, yet little is known about these bacteria. Here we investigated the distribution and phylogenetic status of SAUL. A meta-analysis of the available literature revealed the widespread distribution of this clade and its association with taxonomically varied sponge hosts. Phylogenetic analyses, conducted using both 16S rRNA gene-based phylogeny and concatenated marker protein sequences, revealed that SAUL is a sister clade of the candidate phylum 'Latescibacteria'. Furthermore, we conducted a comprehensive analysis of two draft genomes assembled from sponge metagenomes, revealing novel insights into the physiology of this symbiont. Metabolic reconstruction suggested that SAUL members are aerobic bacteria with facultative anaerobic metabolism, with the capacity to degrade multiple sponge- and algae-derived carbohydrates. We described for the first time in a sponge symbiont the putative genomic capacity to transport phosphate into the cell and to produce and store polyphosphate granules, presumably constituting a phosphate reservoir for the sponge host in deprivation periods. Our findings suggest that the lifestyle of SAUL is symbiotic with the host sponge, and identify symbiont factors which may facilitate the establishment and maintenance of this relationship.

Selected Topics in Aerobic Bacteriology.

Aerobic Gram-positive and Gram-negative bacteria can be important pathogens in the immunocompromised host. These bacteria can be found in many environments, as part of the normal microbiota of the human host and animals, in soil and water, on plants, on fomites in the hospital, and on hospital equipment. This review provides information from relevant studies about what are the most common aerobic bacteria associated with patients who have cancer and/or are being treated for it, or who have other diseases which lead to immunodeficiencies, such as HIV, multiple myeloma, aplastic anemia, chronic diseases, and aging. A discussion of the appropriate laboratory tests needed for diagnosis of aerobic infections and information about antibiotics and susceptibility testing are also included.

Nocardioides ungokensis sp. nov., isolated from lake sediment.

A Gram-reaction-positive, aerobic, coccus- to rod-shaped, non-motile, non-spore-forming bacterium (strain UKS-03T) was isolated from a sediment sample of Ungok Lake in Gochang, Republic of Korea. The taxonomic position of this bacterium was determined in an investigation based on a polyphasic approach. On the basis of 16S rRNA gene sequence analysis, strain UKS-03T was shown to belong to the family Nocardioidaceae and to be related most closely to Nocardioides ginsengisegetis Gsoil 485T (98.5 % similarity), Nocardioides koreensis MSL-09T (98.4 %) and 'Nocardioides panaciterrulae' Gsoil 958 (97.3 %). Strain UKS-03T was characterized chemotaxonomically as having ll-2,6-diaminopimelic acid in its cell-wall peptidoglycan, MK-8(H4) as the predominant menaquinone, diphosphatidylglycerol and phosphatidylglycerol as the main polar lipids, and iso-C16 : 0, C17 : 1ω8c and C17 : 0 10-methyl as its major fatty acids. The G+C content of the genomic DNA was 71.9 mol%. Mean DNA-DNA relatedness values between strain UKS-03T and N. ginsengisegetis Gsoil 485T, N. koreensis KCTC 19272T and 'N. panaciterrulae' Gsoil 958 were 37.5 ± 7.2, 6.8 ± 0.9 and 3.1 ± 0.7 %, respectively. On the basis of the data from this polyphasic taxonomic study, strain UKS-03T represents a novel species of the genus Nocardioides, for which the name Nocardioides ungokensis sp. nov. is proposed. The type strain is UKS-03T ( = KACC 18304T = LMG 28591T).

Nocardioides echinoideorum sp. nov., isolated from sea urchins (Tripneustes gratilla).

A Gram-stain-positive, aerobic, non-motile, rod-shaped, yellow-pigment-producing bacterium, (designated strain CC-CZW004T), was isolated from seafood samples (sea urchins) at Penghu Island in Taiwan. Strain CC-CZW004T grew optimally at pH 7.0 and 30 °C in the presence of 3 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by strain CC-CZW004T with respect to other members of the genus Nocardioides. The novel strain shared highest 16S rRNA gene sequence similarities to Nocardioides daejeonensis JCM 16922T (96.4 %), Nocardioides pacificus JCM 19260T (96.3 %), and Marmoricola scoriae JCM 17444T (96.2 %). The major fatty acids of strain CC-CZW004T consisted of C17:0, C16:1ω5c, C17:1ω8c`, iso-C16:0 and C19:1ω11c/C19:1ω9c (summed feature 6). The diagnostic diamino acid in the cell wall was ll-2,6-diaminopimelic acid. The polar lipid profile was composed of major amounts of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and aminophospholipid. The DNA G+C content was 73.3 mol%. The predominant quinone system was menaquinone (MK-8). On the basis of polyphasic taxonomic evidences presented here, strain CC-CZW004T represents a novel species of the genus Nocardioides, for which the name Nocardioides echinoideorum sp. nov. is proposed. The type strain is CC-CZW004T ( = BCRC 16974T = JCM 30276T).

Aerobic bacteria in post surgical wound infections and pattern of their antimicrobial susceptibility in Ayder Teaching and Referral Hospital, Mekelle, Ethiopia.

BACKGROUND: Post surgical wound infections are global problem in the field of surgery associated with long hospital stay, higher treatment expenditure, morbidity and mortality. Hence to address the limited data in Ethiopia on post surgical wound infections, we conducted this research to determine the prevalence and antimicrobial susceptibility patterns of aerobic bacteria in post-surgical wound infected patients in Ayder teaching and referral hospital, Mekelle, Ethiopia. METHODS: Hospital based prospective cross sectional study was carried-out in 128 patients who had undergone surgery in general surgery and orthopaedic wards, and showed symptoms of infection clinically from January to June 2012. Standard bacteriological methods were used for bacterial isolation and antimicrobial susceptibility pattern. RESULTS: A total of 128 patients (98 male and 30 female) with clinical signs of post surgical wound infections were enrolled. The age of the patients ranged from 15-79 years (with mean 35.95 ± 19.01 years). Out of the 128 wound swabs taken, 96/128 (75%) were culture positive aerobically, yielding 123 bacterial isolates. Out of these the predominant bacterial isolates were Staphylococcus aureus 44 (35.77%), Klebsiella species 29 (22.76%) and Coagulase negative Staphylococci (CoNS) 18 (14.63%). No bacterial isolates was found to be sensitive to all antibiotics tested. Isolated bacteria showed 102/123 (82.92%) multi drug resistance to the commonly used antibiotics in the hospital. However, 54/ 65 (83.1%) of Gram negative and 58/58 (100%) of Gram positive isolates were sensitive to Gentamicin and Vancomycin, respectively. CONCLUSION: Prevalence of was Post-operative wound infections rate in this current study was 75% and multi drug resistance was seen in 102/123(82.92%) of the isolates leaving clinicians with few choices of drugs for the treatment of post surgical wound infected patients. This underscores for periodic surveillance of etiologic agent and antibiotic susceptibility to prevent further emergence and spread of resistant bacteria pathogens.

Accuracy of the cytopathology, bacterioscopy, and vaginal flora culture.

INTRODUCTION: An over-population of vaginal microorganisms causing inflammatory processes renders it difficult to properly assess the cytopathological exam that aims to screen precedent cervical lesions. On the contrary, the occurrence of the microbial flora saprophyte does not influence correct cythodiagnosis. OBJECTIVE: To assess the composition of vaginal tract aerobic microorganisms of asymptomatic women in menacme and post-menopause, and to analyze the accuracy of cytopathologic, bacterioscopic exams, and culturing of the flora. METHODS: The women were first submitted to a focused anamnestic interrogatory and then submitted to gynecological exam. A sample of the vaginal fluid was collected with a culture swab and a smear was made on two glass slides for stained bacterioscopic exam (GRAM). The collection of material was then compiled in a cytopathologic smear analysis. All women signed the free and informed consent letter and the project was approved by the Ethics Research Board of Hospital São Paulo - UNIFESP. RESULTS: Bacterioscopy and culture proved to be better than the cytopathologic exam in featuring the bacilli and cocci. The bacterioscopy provided a better detection of the presence of bacilli (p < 0.001); no statistical difference was seen between both exams with respect to the detected cocci. The beta-hemolytic Streptococcus group was of significance in post-menopausal women (p < 0.05). CONCLUSION: In this study, the bacterioscopic and culture exams of the vaginal fluid were more effective in assessing the vaginal flora and in the detection of bacilli, compared to the cytopathological exam.

Vulcaniibacterium tengchongense gen. nov., sp. nov. isolated from a geothermally heated soil sample, and reclassification of Lysobacter thermophilus Wei et al. 2012 as Vulcaniibacterium thermophilum comb. nov.

A thermotolerant Gram-staining negative and aerobic bacterium, designated strain YIM 77520(T), was isolated from a geothermally heated soil sample collected at Rehai National Park, Tengchong, Yunnan Province, South-West China. Cells of the strain were found to be rod-shaped and colonies were light beige and circular. The strain was found to grow in the presence of 0-2 % (w/v) total salts (optimum, 0 %), at pH 6.0-8.0 (optimum, pH 7.0) and 25-55 °C (optimum, 45 °C). The only quinone detected was Q-8 and the genomic DNA G+C content was determined to be 66.9 mol%. The major fatty acids (>10 %) were identified as iso-C16:0 and iso-C15:0. The phospholipids were found to consist of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, five unknown phospholipids and three aminophospholipids. Based on the 16S rRNA gene sequence analysis, strain YIM 77520(T) was found to form a cluster with Lysobacter thermophilus YIM 77875(T) and showed the highest 16S rRNA gene sequence similarity to L. thermophilus YIM 77875(T) (96.0 %). These two strains formed a distinct lineage of the family 'Xanthomonadaceae'. On the basis of the morphological and chemotaxonomic characteristics, as well as genotypic data, a new genus, Vulcaniibacterium gen. nov. is proposed with Vulcaniibacterium tengchongense sp. nov. as the type species. The type strain of V. tengchongense sp. nov. is strain YIM 77520(T) (=DSM 25623(T) = CCTCC AB 2011152(T)). Furthermore we propose that L. thermophilus Wei et al. 2012 is reclassified in the new genus as Vulcaniibacterium thermophilum comb. nov. (type strain YIM 77875(T) = CCTCC AB 2012064(T) = KCTC 32020(T)) based on polyphasic data.

Aliidiomarina sanyensis sp. nov., a hexabromocyclododecane assimilating bacterium from the pool of Spirulina platensis cultivation, Sanya, China.

A novel Gram-negative, rod shaped, motile, non-spore-forming, aerobic, brominated flame retardant hexabromocyclododecane-assimilating bacterium, designated strain GYP-17(T), was isolated from a pool of marine Spirulina platensis cultivation, Sanya, China. Colonies on 1/10 strength of marine Glycerol Enriched Medium plates were circular, dark-brown, 1-2 mm in diameter, and with regular margins. Growth occurred at 10-45 °C, 1-10 % (w/v) NaCl and pH of 7-9. The polar lipids were composed of phosphatidylethanolamine, three unidentified phospholipids and one unidentified polar lipid. The major fatty acids were iso-C17:1ω9c/10-methyl-C16:0 (summed feature 9, 20.75 %), iso-C15:0 (17.70 %) and C16:0 (6.40 %). The major respiratory quinone was Q-8. The DNA G + C content of the type strain was 53.6 mol%. Phylogenetic analysis revealed that strain GYP-17(T) was a member of the genus Aliidiomarina and closely related to Aliidiomarina haloalkalitolerans with a 16S rDNA sequence similarity of 96.36 %. Results from the polyphasic taxonomy study support the conclusion that strain GYP-17(T) represents a novel Aliidiomarina species, for which the name Aliidiomarina sanyensis sp. nov. is proposed. The type strain of A. sanyensis is GYP-17(T) (=KCTC 32218(T) =LMG 27471(T)).

Impacto de la espectrometría de masas por MALDI-TOF MS en la identificación rápida de bacterias aeróbicas y anaeróbicas de importancia clínica / Impact of mass spectrometry by MALDI-TOF MS for the rapid identification of aerobic and anaerobic bacteria of clinical importance

Background: MALDI-TOF MS (Matrix Assisted Laser Desorption Ionization -Time of Flight Mass Spectrometry) technology, recently introduced in the microbiology laboratory has proven to be a precise and rapid method for bacterial identification. Objective: To evaluate the performance, costs associated and turnaround time of MALDI-TOF in a routine laboratory. Material and Method: Five hundred and sixty one clinical isolates (281 aerobes and 280 anaerobes) previously identified by conventional methods were evaluated. Discordances were resolved by means of 16S rRNA sequencing. Results: MALDI-TOF identified 95, 7% of the aerobes isolates and 86, 4% of the anaerobes. The groups with better performance were the enterobacteriacea and Bacteroides spp with 95% and 100% identification at the species level. The error rate of MALDI-TOF and conventional methods compared to sequencing was 0, 39% and 9, 4% respectively. The costs associated were 8 times lower with a turnaround time of 6 hours. Conclusion: MALDI-TOF proved to be simple, precise and less expensive technology compared to the traditional methods.

Introducción: La tecnología MALDI-TOF MS (Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry) incorporada recientemente en el laboratorio de microbiología ha demostrando ser un método rápido y preciso para la identificación bacteriana. Objetivo: Evaluar el desempeño de MALDI-TOF para la identificación de aislados clínicos, comparar los costos asociados y el tiempo en la entrega de resultados en un laboratorio de rutina. Material y Método: Se evaluaron un total de 561 aislados de pacientes (281 aeróbicos y 280 anaeróbicos estrictos) identificados previamente por métodos convencionales, los que fueron identificados por MALDI-TOF. Las discordancias fueron resueltas mediante secuenciación del 16S ARNr. Resultados: MALDI-TOF identificó adecuadamente a 95,7% de los aislados aeróbi-cos y 86,4% de los anaeróbicos estrictos, observándose el mayor porcentajes de identificación a nivel de especie en los grupos de enterobacterias y Bacteroides spp (95 y 100% respectivamente). La tasa de error de MALDI-TOF y métodos convencionales vs secuenciación fue de 0,39 y 9,4%, respectivamente. El costo asociado por identificación fue ocho veces menor que el de los métodos tradicionales con una demora promedio de seis horas en la entrega de resultados. Conclusión: MALDI-TOF mostró ser una tecnología simple, precisa y de menor costo que los métodos tradicionales.

Sialidase activity in aerobic vaginitis is equal to levels during bacterial vaginosis.

OBJECTIVE: To evaluate levels of proinflammatory cytokines and sialidase activity in aerobic vaginitis (AV) in relation to normal vaginal flora and bacterial vaginosis (BV). STUDY DESIGN: In this cross-sectional study, a total of 682 consecutive non-pregnant women attending the gynecology service were assessed and 408 women were included. Vaginal rinsing samples were collected from 223 women with microscopic finding of BV (n=98), aerobic vaginitis (n=25) and normal flora (n=100). Samples were tested for interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor (TNF)-α, and sialidase activity. RESULTS: Compared to women with normal flora, vaginal levels of IL-1ß were highly increased in both BV and AV (p<0.0001). Significantly higher vaginal IL-6 was detected in AV (p<0.0001) but not in BV, in relation to normal flora. Women with AV also presented increased IL-8 levels (p<0.001), while those with BV presented levels similar to normal flora. Sialidase was increased in BV and AV compared with the normal group (p<0.0001) but no difference in sialidase activity was observed between BV and AV. CONCLUSION: A more intense inflammatory host response occurs for AV than for BV when compared with normal flora. Furthermore, the increased sialidase activity in AV and BV indicates that both abnormal vaginal flora types can be harmful to the maintenance of a healthy vaginal environment.

Evaluation of the Bruker Biotyper and Vitek MS matrix-assisted laser desorption ionization-time of flight mass spectrometry systems for identification of nonfermenting gram-negative bacilli isolated from cultures from cystic fibrosis patients.

The Bruker Biotyper and Vitek MS matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) instruments were evaluated for the identification of nonfermenting gram-negative bacilli (NFGNB) by a blinded comparison to conventional biochemical or molecular methods. Two hundred NFGNB that were recovered from cultures from cystic fibrosis patients in the University of Iowa Health Care (UIHC) Microbiology Laboratory between 1 January 2006 and 31 October 2010 were sent to Mayo Clinic for analysis with the Bruker Biotyper (software version 3.0) and to bioMérieux for testing with Vitek MS (SARAMIS database version 3.62). If two attempts at direct colony testing failed to provide an acceptable MALDI-TOF identification, an extraction procedure was performed. The MS identifications from both of these systems were provided to UIHC for comparison to the biochemical or molecular identification that had been reported in the patient record. Isolates with discordant results were analyzed by 16S rRNA gene sequencing at UIHC. After discrepancy testing, the Bruker Biotyper result agreed with the biochemical or molecular method, with 72.5% of isolates to the species level, 5.5% to the complex level, and 19% to the genus level (3% not identified). The level of agreement for Vitek MS was 80% species, 3.5% complex, 6% genus, and 3.5% family (7% not identified). Both MS systems provided rapid (≤3 min per isolate) and reliable identifications. The agreement of combined species/complex/genus-level identification with the reference method was higher for the Bruker Biotyper (97% versus 89.5%, P = 0.004) but required an extraction step more often. Species-level agreement with the reference method was similar for both MS systems (72.5% and 80%, P = 0.099).

The removal of 1,4-dioxane from polyester manufacturing process wastewater using an up-flow Biological Aerated Filter (UBAF) packed with tire chips.

1,4-Dioxane is one of the by-products from the polyester manufacturing process, which has been carelessly discharged into water bodies and is a weak human carcinogen. In this study, a laboratory-scale, up-flow biological aerated filter (UBAF), packed with tire chips, was investigated for the treatment of 1,4-dioxane. The UBAF was fed with effluent, containing an average of 31 mg/L of 1,4-dioxane, discharged from an anaerobic treatment unit at H Co. in the Gumi Industrial Complex, South Korea. In the batch, a maximum of 99.5 % 1,4-dioxane was removed from an influent containing 25.6 mg/L. In the continuous mode, the optimal empty bed contact time (EBCT) and air to liquid flow rate (A:L) were 8.5 hours and 30:1, respectively. It was also found that the removal efficiency of 1,4-dioxane increased with increasing loading rate within the range 0.04 to 0.31 kg 1,4-dioxane/m(3)·day. However, as the COD:1,4-dioxane ratio was increased within the range 3 to 46 (mg/L COD)/(mg/L 1,4-dioxane), the removal efficiency unexpectedly decreased.

Microflora in maxillofacial infections--a changing scenario?

PURPOSE: Advances in isolation and culturing techniques have brought the role of anaerobic bacteria-causing maxillofacial infections to the fore. Recent literature also favors the role of anaerobes in maxillofacial infections. A prospective clinical and microbiological study was designed to check the validity of such claims. PATIENTS AND METHODS: This study included 88 patients who fulfilled the inclusion criteria. Pus was obtained by aspirating the involved spaces and culture and sensitivity tests were performed to determine the microbes involved and their sensitivity to various antibiotics. RESULTS: Upon isolating the various organisms causing infection, it was found that 68.2% were aerobes, 13.6% were mixed infections, and 9.1% were anaerobes. Streptococcus and Peptostreptococcus species were the most common among aerobes and anaerobes, respectively. On determining sensitivity to penicillin, 81.3% were sensitive and 18.8% were resistant. Coagulase-negative Staphylococcus and Staphylococcus aureus were predominantly resistant to penicillin. CONCLUSION: Analysis of the results indicated no change in microflora-causing infections in the maxillofacial region and penicillin remains the drug of choice in treating these infections.

The microbiology of the peri-implant sulcus following successful implantation of oral prosthetic treatments.

BACKGROUND: Oral implants are widely used in partially and fully edentulous patients; however, the integration of an implant can be endangered by factors such as intraoral bacteria or inflammatory reactions. The purpose of this study was to evaluate the microbial flora present in the sulcus around dental implants and to assess the relationship between gingival health and microbial flora present. MATERIALS AND METHODS: Twenty patients who had received oral implants with no complications were followed for a period of 9 months. Assessment of probing depth, the presence of bleeding on probing and microbial sampling from the peri-implant sulcus were performed at three different time points- 4 weeks after surgery, 1 month and 6 months after loading. The samples were taken by paper points and transferred to the microbiology lab in thioglyocolate cultures. In order to do a colony count and isolate the aerobic capnophilic and anerobic bacteria the samples were cultured and incubated on laboratory media. The colonies were also identified using various diagnostic tests. Alterations in the presence of various bacterial species over time and gum health were tested using analysis of variance (ANOVA) with Tukey's test post hoc. RESULTS: The average pocket depth for each patient ranged from 1.37 ± 0.39 mm to 2.55 ± 0.72 mm. The bacteria isolated from the cultured samples included aerobic, facultative anerobic, obligate anerobic and capnophilic bacteria. CONCLUSION: The anerobic conditions created in the peri-implant sulcus might with time enhance the number of anerobic bacteria present following dental implant loading.

Methylobacterium bullatum sp. nov., a methylotrophic bacterium isolated from Funaria hygrometrica.

A novel, pink-pigmented aerobic, facultatively methylotrophic bacterial strain (F3.2(T)) isolated from the phyllosphere of Funaria hygrometrica, was analyzed using a polyphasic approach. Cells were Gram-negative, motile rods, strictly aerobic and non-spore-forming and exhibited surface structures varying in quantity, distribution and morphology. The isolate grew at 10-33°C over a pH range of 5.5-8.0 and in the presence of less than 1.0% NaCl. Strain F3.2(T) shared less than 70% DNA-DNA binding to the next type strain of the genus Methylobacterium (M. adhaesivum DSM 17169(T)). In addition to the major cellular fatty acid C(18:1)ω7c (81.7%), present in all Methylobacterium species (and also members of the genus Alphaproteobacteria), a high value (11.7%) of the fatty acids (summed feature) C(16:1)ω7c and/or iso-C(15:0)2OH was determined. Phylogenetic analyses based on 16S rDNA and methanol dehydrogenase gene sequences, DNA-DNA hybridization values, chemotaxonomic and phenotypic characteristics indicate that the strain F3.2(T) represents a novel species within the genus Methylobacterium. We propose the name Methylobacterium bullatum sp. nov. for this species. The type strain is the strain F3.2(T) (DSM 21893(T)=LMG 24788(T)).

Use of culture and molecular analysis to determine the effect of antibiotic treatment on microbial community diversity and abundance during exacerbation in patients with cystic fibrosis.

BACKGROUND: Anaerobic bacteria are increasingly regarded as important in cystic fibrosis (CF) pulmonary infection. The aim of this study was to determine the effect of antibiotic treatment on aerobic and anaerobic microbial community diversity and abundance during exacerbations in patients with CF. METHODS: Sputum was collected at the start and completion of antibiotic treatment of exacerbations and when clinically stable. Bacteria were quantified and identified following culture, and community composition was also examined using culture-independent methods. RESULTS: Pseudomonas aeruginosa or Burkholderia cepacia complex were detected by culture in 24/26 samples at the start of treatment, 22/26 samples at completion of treatment and 11/13 stable samples. Anaerobic bacteria were detected in all start of treatment and stable samples and in 23/26 completion of treatment samples. Molecular analysis showed greater bacterial diversity within sputum samples than was detected by culture; there was reasonably good agreement between the methods for the presence or absence of aerobic bacteria such as P aeruginosa (κ=0.74) and B cepacia complex (κ=0.92), but agreement was poorer for anaerobes. Both methods showed that the composition of the bacterial community varied between patients but remained relatively stable in most individuals despite treatment. Bacterial abundance decreased transiently following treatment, with this effect more evident for aerobes (median decrease in total viable count 2.3×10(7) cfu/g, p=0.005) than for anaerobes (median decrease in total viable count 3×10(6) cfu/g, p=0.046). CONCLUSION: Antibiotic treatment targeted against aerobes had a minimal effect on abundance of anaerobes and community composition, with both culture and molecular detection methods required for comprehensive characterisation of the microbial community in the CF lung. Further studies are required to determine the clinical significance of and optimal treatment for these newly identified bacteria.