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1.
J Zoo Wildl Med ; 55(2): 301-312, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38875187

ABSTRACT

The wild rhinoceros populations have declined drastically in the past decades because the rhinoceros are heavily hunted for their horns. Zoological institutions aim to conserve rhinoceros populations in captivity, but one of the challenges of ex situ conservation is to provide food sources that resemble those available in the wild. Considering that the mammalian gut microbiota is a pivotal player in their host's health, the gut microbiota of rhinoceros may also play a role in the bioavailability of nutrients. Therefore, this study aims to characterize the fecal microbiome composition of grazing white rhinoceros (WR; Ceratotherium simum) and greater one-horned rhinoceros (GOHR; Rhinoceros unicornis) as well as the browsing black rhinoceros (BR; Diceros bicornis) kept in European zoos. Over the course of 1 yr, 166 fecal samples in total were collected from 9 BR (n = 39), 10 GOHR (n = 56), and 14 WR (n = 71) from 23 zoological institutions. The bacterial composition in the samples was determined using 16S rRNA gene Illumina sequencing. The fecal microbiomes of rhinoceros clustered by species, with BR clustering more distantly from GOHR and WR. Furthermore, the data report clustering of rhinoceros microbiota according to individual rhinoceros and institutional origin, showing that zoological institutions play a significant role in shaping the gut microbiome of rhinoceros species. In addition, BR exhibit a relatively higher microbial diversity than GOHR and WR. BR seem more susceptible to microbial gut changes and appear to have a more diverse microbiome composition among individuals than GOHR and WR. These data expand on the role of gut microbes and can provide baseline data for continued efforts in rhinoceros conservation and health status.


Subject(s)
Animals, Zoo , Gastrointestinal Microbiome , Perissodactyla , Animals , Perissodactyla/microbiology , Animals, Zoo/microbiology , Europe , Bacteria/classification , Bacteria/isolation & purification , Bacteria/genetics , Species Specificity , Feces/microbiology , RNA, Ribosomal, 16S/genetics , RNA, Bacterial/genetics
2.
Infect Genet Evol ; 87: 104644, 2021 01.
Article in English | MEDLINE | ID: mdl-33246081

ABSTRACT

INTRODUCTION: Pemphigus is a chronic autoimmune blistering disease. Pemphigus blisters can damage the natural skin barrier and increase the risk of life-threatening conditions. Colonization of pemphigus wounds with methicillin-resistant Staphylococcus aureus (MRSA) prolongs wound healing and increases mortality rate. Assessing MRSA prevalence, types, and toxin and adhesion genes can facilitate the detection of MRSA strains which cause infections, selection of appropriate treatments, and healing of pemphigus wounds. This study aimed to determine the SCCmec, the direct repeat unit (dru) types (dts), and the toxin, MSCRAMM, and biofilm genes of MRSA strains isolated from pemphigus wounds. METHODS: In this cross-sectional study, 118 S. aureus isolates were gathered from 118 patients with pemphigus. MRSA detection was performed using the mecA gene. Using the polymerase chain reaction method, all MRSA isolates were assessed for the presence of the sea, seb, sec, tst, eta, pvl, hla, hlb, MSCRAMM, and ica genes. Typing and subtyping were performed through respectively SCCmec typing and dru typing methods. The Bionumerics software was used for analyzing the data and drawing the minimum spanning tree. FINDINGS: From 118 S. aureus isolates, 51 were MRSA. SCCmec typing revealed the prevalence of SCCmec II with a prevalence of 64.7% (33 out of 51 isolates) and SCCmec III with a prevalence of 35.3% (18 out of 51 isolates). Dru typing indicated seven dts, namely dts 10a, 10g, 10m, 13i, 8h, 8i, and 9ca in two main clusters. The dt9ca was a new dru type and was registered in the dru-typing database (www.dru-typing.org). The prevalence rates of the hla, sea, and sec genes in MRSA isolates were respectively 54.9%, 27.4%, and 1.9%, while the hlb, seb, eta, and pvl genes were not detected at all. Only one MRSA with SCCmec III and dt10a carried the tst encoding gene. MSCRAMM gene analysis revealed the high prevalence of the eno (31.3%) and the fib (21.5%) genes. The prevalence rates of the icaA and icaD biofilm formation genes were 3.9% and 5.8%, respectively. There were no significant differences between the two detected SCCmec types and between the two detected dts clusters respecting the prevalence of the encoding genes of virulence factors and MSCRAMMs. CONCLUSION: The toxin genes hla and sea are prevalent among MRSA strains with SCCmec II and III isolated from pemphigus wounds. The most prevalent dts are dt10a and dt10g among MRSA with SCCmec III and dt8h and dt8i among MRSA with SCCmec II.


Subject(s)
Adhesins, Bacterial/genetics , Anti-Bacterial Agents/therapeutic use , Bacterial Toxins/genetics , Biofilms/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/genetics , Pemphigus/microbiology , Virulence Factors/genetics , Cross-Sectional Studies , Genetic Variation , Genotype , Humans , Iran/epidemiology , Pemphigus/drug therapy
3.
Sci Total Environ ; 741: 140404, 2020 Nov 01.
Article in English | MEDLINE | ID: mdl-32887011

ABSTRACT

Allergic rhinitis caused by pollen exposure is one of the most common allergic diseases. Therefore monitoring pollen levels in ambient air is an important tool in research and health care. Most European monitoring stations collect airborne pollen at rooftop levels for measurements in the larger surrounding of the sampling station, and not in the direct environment of sensitized subjects. Here we present the development and evaluation of a portable pollen sampler, called "Pollensniffer", that was designed to collect pollen in the immediate environment of allergic subjects. Validation of the Pollensniffer against the standard volumetric pollen sampler showed for most pollen types high correlations between the number of pollen collected by those two devices (Spearman's Correlation Coefficient > 0.8); the Pollensniffer appeared to collect on average 5.8 times more pollen per hour than the static sampler. Pollen monitoring was performed using this Pollensniffer at street level at 3 different locations in the city of Leiden during 22 weeks in 2017 and 21 weeks in 2018, during three 15-min periods a day and at one day in the week. The results showed that the pollen levels for birch and grass pollen can significantly differ from location to location and per time of day. Furthermore, the Pollensniffer measurements at street level showed that birch and grass pollen grains were detected 1 1/2 and 2-3 weeks, respectively, before detection at rooftop level. The street measurements show that allergic subjects can encounter varying pollen levels throughout the city and that they can be exposed to grass and birch pollen and may experience hay fever symptoms, even before the sampler at rooftop level registers these pollen.


Subject(s)
Allergens , Rhinitis, Allergic, Seasonal , Betula , Cities , Humans , Pollen/immunology
4.
PLoS One ; 15(6): e0235093, 2020.
Article in English | MEDLINE | ID: mdl-32584878

ABSTRACT

Bacterial biofilms are one of the major issues in the treatment of chronic infections such as chronic wounds, where biofilms are typically polymicrobial. The synergy between species can occur during most polymicrobial infections, where antimicrobial resistance enhances as a result. Furthermore, self-produced extracellular polymeric substance (EPS) in biofilms results in a high tolerance to antibiotics that complicates wound healing. Since most antibiotics fail to remove biofilms in chronic infections, new therapeutic modalities may be required. Disruption of EPS is one of the effective approaches for biofilm eradication. Therefore, degradation of EPS using enzymes may result in improved chronic wounds healing. In the current study, we investigated the efficacy of trypsin, ß-glucosidase, and DNase I enzymes on the degradation of dual-species biofilms of Pseudomonas aeruginosa and Staphylococcus aureus in a wound-like medium. These species are the two most common bacteria associated with biofilm formation in chronic wounds. Moreover, the reduction of minimum biofilm eradication concentration (MBEC) of meropenem and amikacin was evaluated when combined with enzymes. The minimum effective concentrations of trypsin, ß-glucosidase, and DNase I enzymes to degrade biofilms were 1 µg/ml, 8 U/ml, and 150 U/ml, respectively. Combination of 0.15 µg/ml trypsin and 50 U/ml DNase I had a significant effect on S. aureus-P. aeruginosa biofilms which resulted in the dispersal and dissolution of all biofilms. In the presence of the enzymatic mixture, MBECs of antibiotics showed a significant decrease (p < 0.05), at least 2.5 fold. We found that trypsin/DNase I mixture can be used as an anti-biofilm agent against dual-species biofilms of S. aureus-P. aeruginosa.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biofilms , Pseudomonas Infections/drug therapy , Pseudomonas aeruginosa/physiology , Staphylococcal Infections/drug therapy , Staphylococcus aureus/physiology , Wound Infection/drug therapy , Wounds and Injuries/microbiology , Biofilms/drug effects , Biofilms/growth & development , Drug Therapy, Combination , Humans , Wound Infection/microbiology
5.
Environ Monit Assess ; 192(5): 269, 2020 Apr 06.
Article in English | MEDLINE | ID: mdl-32253518

ABSTRACT

The recent availability of small and low-cost sensor carrying unmanned aerial systems (UAS, commonly known as drones) coupled with advances in image processing software (i.e., structure from motion photogrammetry) has made drone-collected imagery a potentially valuable tool for rangeland inventory and monitoring. Drone-imagery methods can observe larger extents to estimate indicators at landscape scales with higher confidence than traditional field sampling. They also have the potential to replace field methods in some instances and enable the development of indicators not measurable from the ground. Much research has already demonstrated that several quantitative rangeland indicators can be estimated from high-resolution imagery. Developing a suite of monitoring methods that are useful for supporting management decisions (e.g., repeatable, cost-effective, and validated against field methods) will require additional exploration to develop best practices for image acquisition and analytical workflows that can efficiently estimate multiple indicators. We embedded with a Bureau of Land Management (BLM) field monitoring crew in Northern California, USA to compare field-measured and imagery-derived indicator values and to evaluate the logistics of using small UAS within the framework of an existing monitoring program. The unified workflow we developed to measure fractional cover, canopy gaps, and vegetation height was specific for the sagebrush steppe, an ecosystem that is common in other BLM managed lands. The correspondence between imagery and field methods yielded encouraging agreement while revealing systematic differences between the methods. Workflow best practices for producing repeatable rangeland indicators is likely to vary by vegetation composition and phenology. An online space dedicated to sharing imagery-based workflows could spur collaboration among researchers and quicken the pace of integrating drone-imagery data within adaptive management of rangelands. Though drone-imagery methods are not likely to replace most field methods in large monitoring programs, they could be a valuable enhancement for pressing local management needs.


Subject(s)
Conservation of Natural Resources , Environmental Monitoring/methods , Remote Sensing Technology , Aircraft , California , Ecosystem , Image Processing, Computer-Assisted
6.
Microb Pathog ; 139: 103894, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31805320

ABSTRACT

INTRODUCTION: Tuberculosis (TB) is considered as a serious complication of organ transplant; therefore, the detection and appropriate treatment of active TB infection is highly recommended for the reduction of mortality in the future. The aim of this review was to conduct a systematic review and meta-analysis assessing the prevalence of active TB infection in transplant recipients (TRs). MATERIAL AND METHODS: Electronic databases, including MEDLINE (via PubMed), SCOPUS and Web of Science were searched up to December 24, 2017. The prevalence of active TB was estimated using the random effects meta-analysis. Heterogeneity was evaluated by subgroup analysis. Data were analyzed by STATA version 14. RESULTS: The pooled prevalence of post-transplant active TB was estimated 3% [95% CI: 2-3]. The pooled prevalence of active TB in different transplant forms was as follows: renal,3% [95% CI: 2-4]; stem cell transplant (SCT), 1% [95% CI: 0-3]; lung, 4% [95% CI: 2-6]; heart, 3% [95% CI: 2-4]; liver, 1% [95% CI: 1], and hematopoietic stem cell transplant (HSCT), 2% [95% CI: 1-3]. The prevalence of different clinical presentations of TB was as follows: pulmonary TB (59%; 95% CI: 54-65), extra pulmonary TB (27%; 95% CI: 21-33), disseminated TB (15%; 95% CI: 12-19) and miliary TB (8%; 95% CI: 4-13). The pooled prevalence of different diagnostic tests was as follows: chest X-ray, 57% [95% CI, 46-67]; culture, 56% [95% CI, 45-68]; smear, 49% [95% CI, 40-58]; PCR, 43% [95% CI, 40-58]; histology, 26% [95% CI, 20-32], and tuberculin skin test, 19% [95% CI, 10-28]. CONCLUSION: A high suspicion level for TB, the early diagnosis and the prompt initiation of therapy could increase the survival rates among SOT patients. Overall, renal and lung TRs appear to have a higher predisposition for acquiring TB than other type of recipients. Monitoring of the high-risk recipients, prompt diagnosis, and appropriate treatment are required to manage TB infection among TRs especially in endemic areas.


Subject(s)
Transplant Recipients , Tuberculosis/epidemiology , Tuberculosis/etiology , Disease Management , Disease Susceptibility , Humans , Organ Transplantation/adverse effects , Prevalence , Public Health Surveillance , Tuberculosis/diagnosis , Tuberculosis/therapy
7.
BMC Microbiol ; 19(1): 291, 2019 12 12.
Article in English | MEDLINE | ID: mdl-31830915

ABSTRACT

BACKGROUND: Pseudomonas aeruginosa is a nosocomial pathogen that causes severe infections in immunocompromised patients. Biofilm plays a significant role in the resistance of this bacterium and complicates the treatment of its infections. In this study, the effect of lyticase and ß-glucosidase enzymes on the degradation of biofilms of P. aeruginosa strains isolated from cystic fibrosis and burn wound infections were assessed. Moreover, the decrease of ceftazidime minimum biofilm eliminating concentrations (MBEC) after enzymatic treatment was evaluated. RESULTS: This study demonstrated the effectiveness of both enzymes in degrading the biofilms of P. aeruginosa. In contrast to the lyticase enzyme, ß-glucosidase reduced the ceftazidime MBECs significantly (P < 0.05). Both enzymes had no cytotoxic effect on the A-549 human lung carcinoma epithelial cell lines and A-431 human epidermoid carcinoma cell lines. CONCLUSION: Considering the characteristics of the ß-glucosidase enzyme, which includes the notable degradation of P. aeruginosa biofilms and a significant decrease in the ceftazidime MBECs and non-toxicity for eukaryotic cells, this enzyme can be a promising therapeutic candidate for degradation of biofilms in burn wound patients, but further studies are needed.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Glucan Endo-1,3-beta-D-Glucosidase/pharmacology , Multienzyme Complexes/pharmacology , Peptide Hydrolases/pharmacology , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/genetics , beta-Glucosidase/pharmacology , A549 Cells , Burns/microbiology , Cell Line, Tumor , Cell Survival/drug effects , Cystic Fibrosis/microbiology , Humans , Microbial Sensitivity Tests , Pseudomonas Infections/microbiology
8.
J Med Microbiol ; 67(7): 915-921, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29873628

ABSTRACT

PURPOSE: Staphylococcus haemolyticus has emerged as a highly antimicrobial-resistant healthcare-associated pathogen, in particular for patients admitted to neonatal intensive care. The objective of this study was to study the nature of SCCmec types among MDR-SH strains isolated from paediatric patients. METHODOLOGY: S. haemolyticus strains (n=60) were isolated from paediatric patients. Antibiotic resistance patterns were established using the disk agar diffusion and micro-broth dilution methods. SCCmec typing was performed using whole-genome sequencing (WGS) and an additional PCR analysis. RESULTS: All S. haemolyticus isolates demonstrated multidrug resistance. Using WGS, various novel mec types and combinations of SCCmec types were found, including a new composite island [SCCmec type V (Vd)+SCC cad/ars/cop] comprising 30 % of the strains. SCCmec type V was identified in 23 % of the isolates. A combination of the mecA gene enclosed by two copies of IS431 and absence of the mecRI and ccr genes was identified in 11 strains. In total, mecA regulatory genes were absent in all SH isolates used in this study. CONCLUSION: A high diversity of SCCmec elements with the prevalence of a new composite island was determined among MRSH strains. The structure of the composite island represented by MDR-SH strains in this study, in combination with the presence of a restriction-modification system type III, is described for the first time in this study. The presence of an 8 bp direct repeat (DR) and the sequences flanking the DR may support the integration of the mecA gene complex as a composite transposon (IS431-mecA-IS431) independently from recombinase genes.


Subject(s)
Drug Resistance, Multiple, Bacterial , Genes, Bacterial , Genetic Variation , Genomic Islands , Staphylococcal Infections/microbiology , Staphylococcus haemolyticus/drug effects , Staphylococcus haemolyticus/genetics , Anti-Bacterial Agents , Child, Preschool , Genotyping Techniques , Humans , Infant , Infant, Newborn , Microbial Sensitivity Tests , Polymerase Chain Reaction , Sequence Analysis, DNA , Staphylococcus haemolyticus/classification , Staphylococcus haemolyticus/isolation & purification , Whole Genome Sequencing
9.
Pediatr Infect Dis J ; 37(2): 186-190, 2018 02.
Article in English | MEDLINE | ID: mdl-28767617

ABSTRACT

BACKGROUND: Group B Streptococcus (GBS or S. agalactiae) is a major cause of severe disease in neonates. In perinatal infections or early-onset disease, GBS is transmitted vertically to the newborn from the birth canal during labor and delivery. Limited information is available on the prevalence of GBS recto-vaginal colonization among pregnant women in Iran. METHODS: We performed a systematic search by using different electronic databases including Medline (via Pubmed), Embase, Web of Science and Iranian Database. Meta-analysis was performed by Comprehensive Meta-Analysis (Biostat V2.2) software. RESULTS: Of 250 articles published from January 2000 to September 2016, 25 studies that reported incidence of GBS colonization in pregnant women were included in this review. The meta-analyses showed that the prevalence of GBS colonization among Iranian pregnant women was 9.8% (95% confidence interval, 7.9-12). CONCLUSIONS: The results of this study indicate that GBS screening measures and chemoprophylaxis guidelines concerning GBS infections must be established for pregnant women in Iran, and these guidelines must provide guidance for obstetricians, midwives and neonatologists on the prevention of GBS infections.


Subject(s)
Pregnancy Complications, Infectious/epidemiology , Streptococcal Infections/epidemiology , Streptococcus agalactiae , Carrier State/epidemiology , Female , Humans , Iran/epidemiology , Pregnancy , Prevalence , Rectum/microbiology , Vagina/microbiology
10.
J Glob Antimicrob Resist ; 12: 202-206, 2018 03.
Article in English | MEDLINE | ID: mdl-29107767

ABSTRACT

OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) is considered a major cause of infection and mortality in burn patients, especially when nosocomially acquired. However, limited information is available on the prevalence of MRSA among burn patients in Iran. METHODS: A systematic search was performed using different electronic databases including Medline (via PubMed), Embase, Web of Science and Iranian Database. A meta-analysis was performed using Comprehensive Meta-Analysis Software (BioStat v.2.2). Use of a fixed- or random-effects model was used based on a heterogeneity test, and publication bias was assessed using Begg rank correlation and Egger weighted regression methods. RESULTS: Of 555 articles published from January 2000 to January 2016, 13 studies were included in this review. The meta-analyses showed that the prevalence of MRSA infection in burn patients was 77.9% (95% confidence interval 70.2-84.0%) among culture-positive cases. CONCLUSIONS: The results of this study indicate that the prevalence of MRSA among burn patients is very high in Iran. Thus, a comprehensive infection control strategy based on hand hygiene, education and training in antibiotic prescribing, environmental cleaning, contact precautions, good antibiotic stewardship and an active surveillance system on the basis of international criteria is urgently needed.


Subject(s)
Burns/microbiology , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Staphylococcal Infections/microbiology , Anti-Bacterial Agents/pharmacology , Humans , Iran/epidemiology , Methicillin/pharmacology , Methicillin-Resistant Staphylococcus aureus/classification , Methicillin-Resistant Staphylococcus aureus/genetics
11.
PLoS One ; 12(12): e0189539, 2017.
Article in English | MEDLINE | ID: mdl-29281709

ABSTRACT

Earth's future carbon balance and regional carbon exchange dynamics are inextricably linked to plant photosynthesis. Spectral vegetation indices are widely used as proxies for vegetation greenness and to estimate state variables such as vegetation cover and leaf area index. However, the capacity of green leaves to take up carbon can change throughout the season. We quantify photosynthetic capacity as the maximum rate of RuBP carboxylation (Vcmax) and regeneration (Jmax). Vcmax and Jmax vary within-season due to interactions between ontogenetic processes and meteorological variables. Remote sensing-based estimation of Vcmax and Jmax using leaf reflectance spectra is promising, but temporal variation in relationships between these key determinants of photosynthetic capacity, leaf reflectance spectra, and the models that link these variables has not been evaluated. To address this issue, we studied hybrid poplar (Populus spp.) during a 7-week mid-summer period to quantify seasonally-dynamic relationships between Vcmax, Jmax, and leaf spectra. We compared in situ estimates of Vcmax and Jmax from gas exchange measurements to estimates of Vcmax and Jmax derived from partial least squares regression (PLSR) and fresh-leaf reflectance spectroscopy. PLSR models were robust despite dynamic temporal variation in Vcmax and Jmax throughout the study period. Within-population variation in plant stress modestly reduced PLSR model predictive capacity. Hyperspectral vegetation indices were well-correlated to Vcmax and Jmax, including the widely-used Normalized Difference Vegetation Index. Our results show that hyperspectral estimation of plant physiological traits using PLSR may be robust to temporal variation. Additionally, hyperspectral vegetation indices may be sufficient to detect temporal changes in photosynthetic capacity in contexts similar to those studied here. Overall, our results highlight the potential for hyperspectral remote sensing to estimate determinants of photosynthetic capacity during periods with dynamic temporal variations related to seasonality and plant stress, thereby improving estimates of plant productivity and characterization of the associated carbon budget.


Subject(s)
Photosynthesis , Plant Leaves/physiology , Chlorophyll/metabolism , Plant Leaves/metabolism , Regression Analysis , Seasons
12.
Genome Announc ; 5(29)2017 Jul 20.
Article in English | MEDLINE | ID: mdl-28729278

ABSTRACT

Using Illumina HiSeq and PacBio technologies, we sequenced the genome of the multidrug-resistant bacterium Staphylococcus haemolyticus, originating from a bloodstream infection in a neonate. The sequence data can be used as an accurate reference sequence.

13.
New Phytol ; 214(3): 1033-1048, 2017 May.
Article in English | MEDLINE | ID: mdl-27381054

ABSTRACT

Leaf age structures the phenology and development of plants, as well as the evolution of leaf traits over life histories. However, a general method for efficiently estimating leaf age across forests and canopy environments is lacking. Here, we explored the potential for a statistical model, previously developed for Peruvian sunlit leaves, to consistently predict leaf ages from leaf reflectance spectra across two contrasting forests in Peru and Brazil and across diverse canopy environments. The model performed well for independent Brazilian sunlit and shade canopy leaves (R2  = 0.75-0.78), suggesting that canopy leaves (and their associated spectra) follow constrained developmental trajectories even in contrasting forests. The model did not perform as well for mid-canopy and understory leaves (R2  = 0.27-0.29), because leaves in different environments have distinct traits and trait developmental trajectories. When we accounted for distinct environment-trait linkages - either by explicitly including traits and environments in the model, or, even better, by re-parameterizing the spectra-only model to implicitly capture distinct trait-trajectories in different environments - we achieved a more general model that well-predicted leaf age across forests and environments (R2  = 0.79). Fundamental rules, linked to leaf environments, constrain the development of leaf traits and allow for general prediction of leaf age from spectra across species, sites and canopy environments.


Subject(s)
Forests , Light , Plant Leaves/growth & development , Plant Leaves/physiology , Quantitative Trait, Heritable , Tropical Climate , Brazil , Geography , Models, Theoretical , Peru , Regression Analysis , Trees/anatomy & histology , Trees/growth & development
14.
Iran J Microbiol ; 8(3): 159-160, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27928481
15.
Environ Monit Assess ; 188(12): 676, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27858259

ABSTRACT

Time series of vegetation indices and remotely sensed phenological data offer insights about the patterns in vegetation dynamics. Both are useful sources of information for analyzing and monitoring ecosystem responses to environmental variations caused by natural and anthropogenic drivers. In the semi-arid region of Chile, climate variability and recent severe droughts in addition to land-use changes pose threats to the stability of local ecosystems. Normalized difference vegetation index time series (2000-2013) data from the moderate resolution imaging spectroradiometer (MODIS) was processed to monitor the trends and patterns of vegetation productivity and phenology observed over the last decade. An analysis of the relationship between (i) vegetation productivity and (ii) precipitation and temperature data for representative natural land-use cover classes was made. Using these data and ground measurements, productivity estimates were projected for two climate change scenarios (RCP2.6 and RCP8.5) at two altitudinal levels. Results showed negative trends of vegetation productivity below 2000 m a.s.l. and positive trends for higher elevations. Phenology analysis suggested that mountainous ecosystems were starting their growing period earlier in the season, coinciding with a decreased productivity peak during the growing season. The coastal shrubland/grassland land cover class had a significant positive relation with rainfall and a significant negative relation with temperature, suggesting that these ecosystems are vulnerable to climate change. Future productivity projections indicate that under an RCP8.5 climate change scenario, productivity could decline by 12% in the period of 2060-2100, leading to a severe vegetation degradation at lower altitudes and in drier areas.


Subject(s)
Climate Change , Plant Development , Altitude , Chile , Climate , Droughts , Ecosystem , Environmental Monitoring , Grassland , Rivers , Satellite Imagery , Seasons , Temperature
16.
Genome Announc ; 4(3)2016 May 26.
Article in English | MEDLINE | ID: mdl-27231361

ABSTRACT

We present the first genome sequence for a strain of the main mycetoma causative agent, Madurella mycetomatis This 36.7-Mb genome sequence will offer new insights into the pathogenesis of mycetoma, and it will contribute to the development of better therapies for this neglected tropical disease.

17.
Int J Food Microbiol ; 228: 10-3, 2016 Jul 02.
Article in English | MEDLINE | ID: mdl-27082892

ABSTRACT

Extraintestinal pathogenic Escherichia coli sequence type 131 (ST131), typically fluoroquinolone-resistant (FQ-R) and/or extended-spectrum ß-lactamase (ESBL)-producing, has emerged globally. Among clinical isolates, ST131, primarily its H30-R and H30-Rx subclones, accounts for most antimicrobial-resistant E. coli and is the dominant E. coli strain worldwide. We assessed its prevalence and characteristics among raw chicken meat samples on sale in Palermo, Italy. A collection of 237 fluoroquinolone resistant and ESBL/AmpC producing E. coli isolates, which had been isolated from processed retail chicken meat in the period May 2013-April 2015, was analyzed. Established polymerase chain reaction methods were used to define ST131 and its H30 subclones, ESBL, AmpC, and plasmid-mediated quinolone resistance (PMQR) determinants. Amplified Fragment Length Polymorphism (AFLP) was performed to assess the relatedness among ST131 isolates. Out of the 237 E. coli isolates, 12 isolates belonged to the phylogenetic group B2. Based on the molecular definition of ExPEC, all isolates were attributed with the status of ExPEC. SNP-PCR results confirmed that nine isolates were ST131. SNP-PCR for H30-R and H30-Rx subclones showed that six and three ExPEC ST131 were positive for H30-R and H30-Rx, respectively. The results of AFLP showed that, except for four isolates grouped into two clusters which proved to be indistinguishable, the isolates under study were genetically heterogeneous. To the best of our knowledge, this is the first report of H30-R and H30-Rx subclones in animal food samples. Our findings appear to support the role of food chain in their transmission to humans.


Subject(s)
Chickens/microbiology , Extraintestinal Pathogenic Escherichia coli/isolation & purification , Food Microbiology , Meat/microbiology , Amplified Fragment Length Polymorphism Analysis , Animals , Drug Resistance, Bacterial , Extraintestinal Pathogenic Escherichia coli/classification , Extraintestinal Pathogenic Escherichia coli/drug effects , Fluoroquinolones/pharmacology , Italy , Phylogeny , Plasmids/genetics
18.
J Microbiol Methods ; 121: 44-9, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26747625

ABSTRACT

The fungal species Trichoderma harzianum is widely used as a biological agent in crop protection. To verify the continued presence of this fungus on plant roots manually inoculated with T. harzianum strain T22, a Q-PCR was designed using specific probes for this particular strain. To develop these molecular diagnostic tools, genome mining was first carried out to retrieve putative new regions by which different strains of T. harzianum could be distinguished. Subsequently, Sanger sequencing of the L-aminoacid oxidase gene (aox1) in T. harzianum was applied to determine the mutations differing between various strains isolated from the Trichoderma collection of Koppert Biological Systems. Based on the sequence information obtained, a set of hydrolysis probes was subsequently developed which discriminated T. harzianum T22 strains varying in only a single nucleotide. Probes designed for two strains uniquely recognized the respective strains in Q-PCR with a detection limit of 12,5ng DNA. Titration assays in which T. harzianum DNA from distinct strains was varied further underscored the specificity of the probes. Lastly, fungal DNA extracted from roots of greenhouse cultured tomato plants was analyzed using the probe-based assay. DNA from T. harzianum strain T22 could readily be identified on roots of greenhouse reared tomato plants inoculated with varying concentrations up to one week after treatment with a detection limit of 3e6 colony forming units of T. harzianum T22. We conclude that the Q-PCR method is a reliable and robust method for assessing the presence and quantity of T. harzianum strain T22 in manually inoculated plant material. Our method provides scope for the development of DNA based strain specific identification of additional strains of Trichoderma and other fungal biological control agents.


Subject(s)
DNA, Fungal/analysis , Multiplex Polymerase Chain Reaction/methods , Mycological Typing Techniques/methods , Plant Roots/microbiology , Solanum lycopersicum/microbiology , Trichoderma/genetics , Trichoderma/isolation & purification , Base Sequence , DNA, Fungal/genetics , Genes, Fungal , Molecular Sequence Data , Mycological Typing Techniques/economics , Soil Microbiology , Symbiosis
19.
Environ Manage ; 57(2): 283-97, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26407556

ABSTRACT

The overexploitation of water resources in arid environments often results in abandonment of large extensions of agricultural lands, which may (1) modify phenological trends, and (2) alter the sensitivity of specific phenophases to environmental triggers. In Mexico, current governmental policies subsidize restoration efforts, to address ecological degradation caused by abandonments; however, there is a need for new approaches to assess their effectiveness. Addressing this, we explore a method to monitor and assess (1) land surface phenology trends in arid agro-ecosystems, and (2) the effect of climatic factors and restoration treatments on the phenology of abandoned agricultural fields. We used 16-day normalized difference vegetation index composites from the moderate resolution imaging spectroradiometer from 2000 to 2009 to derive seasonal phenometrics. We then derived phenoclimatic variables and land cover thematic maps, to serve as a set of independent factors that influence vegetation phenology. We conducted a multivariate analysis of variance to analyze phenological trends among land cover types, and developed multiple linear regression models to assess influential climatic factors driving phenology per land cover analyzed. Our results suggest that the start and length of the growing season had different responses to environmental factors depending on land cover type. Our analysis also suggests possible establishment of arid adapted species (from surrounding ecosystems) in abandoned fields with longer times since abandonment. Using this approach, we were able increase our understanding on how climatic factors influence phenology on degraded arid agro-ecosystems, and how this systems evolve after disturbance.


Subject(s)
Agriculture/methods , Conservation of Natural Resources , Climate , Crops, Agricultural/growth & development , Ecosystem , Linear Models , Mexico , Models, Theoretical , Multivariate Analysis , Seasons , Time Factors
20.
Infect Genet Evol ; 38: 19-21, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26656742

ABSTRACT

Staphylococcus haemolyticus is a healthcare-associated pathogen and can cause a variety of lifethreatening infections. Additionally, multi-drug resistance (MDR), in particular methicillin-resistant S. haemolyticus (MRSH) isolates, have emerged. Dissemination of such strains can be of great concern in the hospital environment. A total number of 20S. haemolyticus isolates from blood cultures obtained from children were included in this study. A high prevalence of MDR-MRSH isolates with high MIC values to vancomycin was found and 35% of the isolates were intermediate resistant to vancomycin. Multilocus variable number of tandem repeats analysis (MLVF) revealed 5 MLVF types among 20 isolates of S. haemolyticus. Twelve isolates shared the same MLVF type and were isolated from different wards in a pediatric hospital in Iran. This is a serious alarm for infection control; i.e. in the absence of adequate infection diagnostics and infection control guidelines, these resistant strains can spread to other sectors of a hospital and possibly among the community.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteremia/microbiology , DNA, Bacterial , Drug Resistance, Bacterial , Staphylococcal Infections/microbiology , Staphylococcus haemolyticus/drug effects , Staphylococcus haemolyticus/genetics , Tandem Repeat Sequences , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Microbial Sensitivity Tests , Multilocus Sequence Typing , Staphylococcus haemolyticus/isolation & purification
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