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1.
Infection ; 2024 May 04.
Article in English | MEDLINE | ID: mdl-38703288

ABSTRACT

BACKGROUND: Community-acquired (CA) and healthcare-associated (HCA) infections caused by carbapenemase-producing Enterobacterales (CPE) are not well characterized. The objective was to provide detailed information about the clinical and molecular epidemiological features of nosocomial, HCA and CA infections caused by carbapenemase-producing Klebsiella pneumoniae (CP-Kp) and Escherichia coli (CP-Ec). METHODS: A prospective cohort study was performed in 59 Spanish hospitals from February to March 2019, including the first 10 consecutive patients from whom CP-Kp or CP-Ec were isolated. Patients were stratified according to acquisition type. A multivariate analysis was performed to identify the impact of acquisition type in 30-day mortality. RESULTS: Overall, 386 patients were included (363 [94%] with CP-Kp and 23 [6%] CP-Ec); in 296 patients (76.3%), the CPE was causing an infection. Acquisition was CA in 31 (8.0%) patients, HCA in 183 (47.4%) and nosocomial in 172 (48.3%). Among patients with a HCA acquisition, 100 (54.6%) had been previously admitted to hospital and 71 (38.8%) were nursing home residents. Urinary tract infections accounted for 19/23 (82.6%), 89/130 (68.5%) and 42/143 (29.4%) of CA, HCA and nosocomial infections, respectively. Overall, 68 infections (23%) were bacteremia (8.7%, 17.7% and 30.1% of CA, HCA and nosocomial, respectively). Mortality in infections was 28% (13%, 14.6% and 42.7% of CA, HCA and nosocomial, respectively). Nosocomial bloodstream infections were associated with increased odds for mortality (adjusted OR, 4.00; 95%CI 1.21-13.19). CONCLUSIONS: HCA and CA infections caused by CPE are frequent and clinically significant. This information may be useful for a better understanding of the epidemiology of CPE.

2.
Eur J Clin Microbiol Infect Dis ; 43(4): 797-803, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38356016

ABSTRACT

Fourier-transform infrared (FTIR) spectroscopy has the potential to be used for bacterial typing and outbreak characterization. We evaluated FTIR for the characterization of an outbreak caused by Elizabethkingia miricola. During the 2020-2021 period, 26 isolates (23 clinical and 3 environmental) were collected and analyzed by FTIR (IR Biotyper) and core-genome MLST (cgMLST), in addition to antimicrobial susceptibility testing. FTIR spectroscopy and cgMLST showed that 22 of the isolates were related to the outbreak, including the environmental samples, with only one discordance between both methods. Then, FTIR is useful for E. miricola typing and can be easily implemented in the laboratory.


Subject(s)
Flavobacteriaceae , Humans , Multilocus Sequence Typing , Spectroscopy, Fourier Transform Infrared , Flavobacteriaceae/genetics , Disease Outbreaks
3.
Front Microbiol ; 12: 774386, 2021.
Article in English | MEDLINE | ID: mdl-34867914

ABSTRACT

Circulating recombinant forms (CRFs) are important components of the HIV-1 pandemic. Among 110 reported in the literature, 17 are BF1 intersubtype recombinant, most of which are of South American origin. Among these, all 5 identified in the Southern Cone and neighboring countries, except Brazil, derive from a common recombinant ancestor related to CRF12_BF, which circulates widely in Argentina, as deduced from coincident breakpoints and clustering in phylogenetic trees. In a HIV-1 molecular epidemiological study in Spain, we identified a phylogenetic cluster of 20 samples from 3 separate regions which were of F1 subsubtype, related to the Brazilian strain, in protease-reverse transcriptase (Pr-RT) and of subtype B in integrase. Remarkably, 14 individuals from this cluster (designated BF9) were Paraguayans and only 4 were native Spaniards. HIV-1 transmission was predominantly heterosexual, except for a subcluster of 6 individuals, 5 of which were men who have sex with men. Ten additional database sequences, from Argentina (n = 4), Spain (n = 3), Paraguay (n = 1), Brazil (n = 1), and Italy (n = 1), branched within the BF9 cluster. To determine whether it represents a new CRF, near full-length genome (NFLG) sequences were obtained for 6 viruses from 3 Spanish regions. Bootscan analyses showed a coincident BF1 recombinant structure, with 5 breakpoints, located in p17 gag , integrase, gp120, gp41-rev overlap, and nef, which was identical to that of two BF1 recombinant viruses from Paraguay previously sequenced in NFLGs. Interestingly, none of the breakpoints coincided with those of CRF12_BF. In a maximum likelihood phylogenetic tree, all 8 NFLG sequences grouped in a strongly supported clade segregating from previously identified CRFs and from the CRF12_BF "family" clade. These results allow us to identify a new HIV-1 CRF, designated CRF66_BF. Through a Bayesian coalescent analysis, the most recent common ancestor of CRF66_BF was estimated around 1984 in South America, either in Paraguay or Argentina. Among Pr-RT sequences obtained by us from HIV-1-infected Paraguayans living in Spain, 14 (20.9%) of 67 were of CRF66_BF, suggesting that CRF66_BF may be one of the major HIV-1 genetic forms circulating in Paraguay. CRF66_BF is the first reported non-Brazilian South American HIV-1 CRF_BF unrelated to CRF12_BF.

4.
Viruses ; 13(1)2021 Jan 12.
Article in English | MEDLINE | ID: mdl-33445523

ABSTRACT

The extraordinary genetic variability of human immunodeficiency virus type 1 (HIV-1) group M has led to the identification of 10 subtypes, 102 circulating recombinant forms (CRFs) and numerous unique recombinant forms. Among CRFs, 11 derived from subtypes B and C have been identified in China, Brazil, and Italy. Here we identify a new HIV-1 CRF_BC in Northern Spain. Originally, a phylogenetic cluster of 15 viruses of subtype C in protease-reverse transcriptase was identified in an HIV-1 molecular surveillance study in Spain, most of them from individuals from the Basque Country and heterosexually transmitted. Analyses of near full-length genome sequences from six viruses from three cities revealed that they were BC recombinant with coincident mosaic structures different from known CRFs. This allowed the definition of a new HIV-1 CRF designated CRF108_BC, whose genome is predominantly of subtype C, with four short subtype B fragments. Phylogenetic analyses with database sequences supported a Brazilian ancestry of the parental subtype C strain. Coalescent Bayesian analyses estimated the most recent common ancestor of CRF108_BC in the city of Vitoria, Basque Country, around 2000. CRF108_BC is the first CRF_BC identified in Spain and the second in Europe, after CRF60_BC, both phylogenetically related to Brazilian subtype C strains.


Subject(s)
Genome, Viral , Genotype , HIV Infections/epidemiology , HIV Infections/virology , HIV-1/classification , HIV-1/genetics , Recombination, Genetic , Genetic Variation , Humans , Molecular Epidemiology , Phylogeny , Phylogeography , Public Health Surveillance , Sequence Analysis, DNA , Spain/epidemiology , Viremia
5.
Front Microbiol ; 10: 655, 2019.
Article in English | MEDLINE | ID: mdl-31001231

ABSTRACT

In Western Europe, the HIV-1 epidemic among men who have sex with men (MSM) is dominated by subtype B. However, recently, other genetic forms have been reported to circulate in this population, as evidenced by their grouping in clusters predominantly comprising European individuals. Here we describe four large HIV-1 non-subtype B clusters spreading among MSM in Spain. Samples were collected in 9 regions. A pol fragment was amplified from plasma RNA or blood-extracted DNA. Phylogenetic analyses were performed via maximum likelihood, including database sequences of the same genetic forms as the identified clusters. Times and locations of the most recent common ancestors (MRCA) of clusters were estimated with a Bayesian method. Five large non-subtype B clusters associated with MSM were identified. The largest one, of F1 subtype, was reported previously. The other four were of CRF02_AG (CRF02_1; n = 115) and subtypes A1 (A1_1; n = 66), F1 (F1_3; n = 36), and C (C_7; n = 17). Most individuals belonging to them had been diagnosed of HIV-1 infection in the last 10 years. Each cluster comprised viruses from 3 to 8 Spanish regions and also comprised or was related to viruses from other countries: CRF02_1 comprised a Japanese subcluster and viruses from 8 other countries from Western Europe, Asia, and South America; A1_1 comprised viruses from Portugal, United Kingom, and United States, and was related to the A1 strain circulating in Greece, Albania and Cyprus; F1_3 was related to viruses from Romania; and C_7 comprised viruses from Portugal and was related to a virus from Mozambique. A subcluster within CRF02_1 was associated with heterosexual transmission. Near full-length genomes of each cluster were of uniform genetic form. Times of MRCAs of CRF02_1, A1_1, F1_3, and C_7 were estimated around 1986, 1989, 2013, and 1983, respectively. MRCA locations for CRF02_1 and A1_1 were uncertain (however initial expansions in Spain in Madrid and Vigo, respectively, were estimated) and were most probable in Bilbao, Spain, for F1_3 and Portugal for C_7. These results show that the HIV-1 epidemic among MSM in Spain is becoming increasingly diverse through the expansion of diverse non-subtype B clusters, comprising or related to viruses circulating in other countries.

6.
Biotechnol Biofuels ; 11: 86, 2018.
Article in English | MEDLINE | ID: mdl-29619082

ABSTRACT

BACKGROUND: 2,5-Furandicarboxylic acid is a renewable building block for the production of polyfurandicarboxylates, which are biodegradable polyesters expected to substitute their classical counterparts derived from fossil resources. It may be produced from bio-based 5-hydroxymethylfurfural or 5-methoxymethylfurfural, both obtained by the acidic dehydration of biomass-derived fructose. 5-Methoxymethylfurfural, which is produced in the presence of methanol, generates less by-products and exhibits better storage stability than 5-hydroxymethylfurfural being, therefore, the industrial substrate of choice. RESULTS: In this work, an enzymatic cascade involving three fungal oxidoreductases has been developed for the production of 2,5-furandicarboxylic acid from 5-methoxymethylfurfural. Aryl-alcohol oxidase and unspecific peroxygenase act on 5-methoxymethylfurfural and its partially oxidized derivatives yielding 2,5-furandicarboxylic acid, as well as methanol as a by-product. Methanol oxidase takes advantage of the methanol released for in situ producing H2O2 that, along with that produced by aryl-alcohol oxidase, fuels the peroxygenase reactions. In this way, the enzymatic cascade proceeds independently, with the only input of atmospheric O2, to attain a 70% conversion of initial 5-methoxymethylfurfural. The addition of some exogenous methanol to the reaction further improves the yield to attain an almost complete conversion of 5-methoxymethylfurfural into 2,5-furandicarboxylic acid. CONCLUSIONS: The synergistic action of aryl-alcohol oxidase and unspecific peroxygenase in the presence of 5-methoxymethylfurfural and O2 is sufficient for the production of 2,5-furandicarboxylic acid. The addition of methanol oxidase to the enzymatic cascade increases the 2,5-furandicarboxylic acid yields by oxidizing a reaction by-product to fuel the peroxygenase reactions.

7.
Sci Total Environ ; 574: 744-750, 2017 Jan 01.
Article in English | MEDLINE | ID: mdl-27664761

ABSTRACT

Solar ultraviolet (UV) radiation is one of the most important factors in the development of skin cancer in human, solar erythema and skin aging. Nevertheless, numerous studies have shown the benefits of UV solar radiation in moderate doses, such as the reduction of blood pressure and mental health, treatment of various diseases, and the synthesis of vitamin D in the skin. This paper analyses data from solar ultraviolet erythemal (UVER) irradiance in W/m2 measured in a northern mid-latitude as Valencia (Spain) for the period 2003-2010. To estimate effective solar UV radiation in the production of vitamin D (UVD) we used the relationship proposed by McKenzie et al. (2009). It was obtained for one month for each season the minimum exposure time needed around solar noon and at 9 UTC and 15 UTC (Coordinated Universal Time) to obtain the recommended daily dose of 1000IU. Also, it has been calculated time for erythema induction around solar noon for the same months. The median UVER daily dose during the summer months was 4000J/m2day, and 700J/m2day in winter. With regard to UVD, the median UVD daily dose in summer season was 7700J/m2day, and in winter it was 1000J/m2day. Around noon in January it takes more than two hours of solar exposure to obtain the recommended daily dose of vitamin D, whereas the rest of the year range between 7min on July and 31min on October. For the same months around noon, exposure times to produce erythema were obtained, these being of higher value to the previous. The results show that it is difficult to obtain the recommended vitamin D doses in winter in a northern mid-latitude, as the human body is almost entirely covered in this season.


Subject(s)
Seasons , Sunlight , Ultraviolet Rays , Vitamin D/biosynthesis , Erythema , Humans , Spain
8.
Photochem Photobiol Sci ; 13(4): 671-9, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24535504

ABSTRACT

Exposure to ultraviolet (UV) radiation is a major environmental risk factor in the development of skin cancers and it occurs mainly during outdoor activities. The purpose of this study is to quantify the UV exposure suffered by amateur athletes (tennis players, hikers and runners) in their training schedules. The study on tennis player exposure took place at a tennis club in Valencia during the month of June 2011. With respect to the hiking group, the hikes studied took place in several mountainous areas of Spain and France from June to August 2011. Finally, the exposure suffered by ten runners while participating in a running circuit in the province of Valencia, from March to November 2011, was studied. The athletes were monitored using personal dosimeters (VioSpor), with the tennis players and runners wearing them on the wrist and the hikers on the shoulder. The median daily personal UV exposure for the hikers was 8.1 Standard Erythema Dose (SED) and for the tennis players 7.5 SED per day of training. The runners received a median of 14.6 SED while participating in the running circuit and about 2 SED per competition day. Median daily UV exposure of the hikers and tennis players exceeded 5 SED, which means that, in the case of non-sun-adapted skin type III and the non-use of sun protection, erythema may be induced in these subjects. However, the exposure suffered by the runners did not exceed the maximum personal exposure of 5 SED. Accordingly, it is necessary to encourage the use of high protection sunscreens and protective clothing and to avoid UV exposure in the hottest part of the day.


Subject(s)
Environmental Exposure/analysis , Sports , Ultraviolet Rays , Altitude , Female , France , Humans , Male , Ozone , Radiation Dosage , Radiometry , Running , Seasons , Shoulder , Spain , Tennis , Time Factors , Wrist
9.
Photochem Photobiol ; 90(4): 911-8, 2014.
Article in English | MEDLINE | ID: mdl-24494834

ABSTRACT

Excessive exposure to ultraviolet radiation (UVR) is considered the most important environmental risk factor in the development of melanoma and skin cancer. Outdoor workers are among those with the highest risk from exposure to solar UVR, as their daily activities constantly expose them to this radiation source. A study was carried out in Valencia, Spain, in summer 2012 and involved a group of 11 workers for a period of six 2-day recordings. Sensitive spore-film filter-type personal dosimeters (VioSpor) were used to measure erythemal UVR received by environmental agents in the course of their daily work. Median 2-day UV exposure was 6.2 standard erythema dose (SED), with 1 SED defined as effective 100 J m(-2) when weighted with the Commission Internationale de L'Eclairage's (CIE) erythemal response function. These workers were found to receive a median of 8.3% total daily ambient ultraviolet erythemal radiation. Comparison with the occupational UV exposure limit showed that the subjects had received an erythemal UV dose in excess of occupational guidelines, indicating that protective measures against this risk are highly advisable.

10.
Chemistry ; 20(1): 106-12, 2014 Jan 03.
Article in English | MEDLINE | ID: mdl-24311368

ABSTRACT

Tetrafluorinated analogues of both UDP-galactopyranose and UDP-galactofuranose have been synthesized and assayed against UDP-galactopyranose mutase, a key enzyme for Mycobacterium tuberculosis cell wall biosynthesis. Competition assays and STD-NMR spectroscopy techniques have evidenced not only the first unambiguous case of affinity enhancement through local sugar polyfluorination, but also showed that tetrafluorination can still have a beneficial effect on binding when monofluorination at the same position does not.


Subject(s)
Bacterial Proteins/metabolism , Intramolecular Transferases/metabolism , Bacterial Proteins/antagonists & inhibitors , Biocatalysis , Carbohydrates/chemistry , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/metabolism , Fluorine/chemistry , Galactose/analogs & derivatives , Galactose/chemistry , Galactose/metabolism , Halogenation , Intramolecular Transferases/antagonists & inhibitors , Magnetic Resonance Spectroscopy , Mycobacterium tuberculosis/enzymology , Protein Binding , Uridine Diphosphate/analogs & derivatives , Uridine Diphosphate/chemistry , Uridine Diphosphate/metabolism
11.
Photochem Photobiol Sci ; 12(11): 1976-83, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24057156

ABSTRACT

Children are a special group since epidemiological evidence indicates that excessive exposure to sunlight at an early age increases the risk of skin cancer in later life. The purpose of this study is to quantify children's UV exposure when skiing, using dosimeters (VioSpor) placed on the shoulders of 10 participants. The children received a median daily Standard Erythema Dose of 2.1 within a range of 4.9-0.71, this being approximately 35% of the calculated 24 h ambient UV radiation on the horizontal plane. According to the results obtained, young skiers are exposed to UV radiation that can potentially cause skin damage and erythema and increase the risk of skin cancer in the course of a lifetime. These findings emphasise the need for adequate protective measures against solar radiation when skiing. The results also suggest that sun-protection campaigns should be undertaken aimed at children engaged in outdoor sports, including winter activities.


Subject(s)
Erythema , Radiation Dosage , Skiing , Skin , Ultraviolet Rays , Child , Dose-Response Relationship, Radiation , Erythema/etiology , Humans , Skin/blood supply , Skin/pathology , Skin/radiation effects , Ultraviolet Rays/adverse effects
12.
J Expo Sci Environ Epidemiol ; 23(5): 525-30, 2013.
Article in English | MEDLINE | ID: mdl-22739681

ABSTRACT

Exposure to ultraviolet radiation (UVR) has long been recognized as the most important environmental risk factor for melanoma and skin cancer. Outdoor workers are among the groups most at risk from exposure to solar UVR in their daily activities. Sensitive spore-film filter-type personal dosimeters (VioSpor) were used to measure the biologically effective UVR received by construction workers in the course of their daily work. The study took place in Valencia, Spain, in July 2010 and involved a group of eight workers for a period of 5 days. The median UV exposure was 6.11 standard erythema dose (SED) per day, with 1 SED defined as effective 100 J/m(2) when weighted with the Commission Internationale de L'Eeclairage erythemal response function. These workers were found to receive a median of 13.9% of total daily ambient ultraviolet erythemal radiation (UVER). Comparison with the occupational UVR exposure limit showed that the subjects had received UVER exposure in excess of occupational guidelines, indicating that protective measures against this risk are highly advisable.


Subject(s)
Occupational Exposure , Sunlight , Humans , Skin/radiation effects , Spain
13.
Int J Biometeorol ; 56(2): 371-7, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21560029

ABSTRACT

Ultraviolet (UV) exposure is the major environmental factor involved in the development of skin cancers and occurs mainly during outdoor activities. During summer schools, children receive regular and significant solar ultraviolet erythemal radiation (UVER) while practising outdoor activities. Personal dosimeters (VioSpor) were attached to the shoulders of schoolchildren and used to quantify their exposure to UVER. The study took place in Valencia, Spain, during July 2008, with three age groups (7-8, 9-10 and 11-12 years old) and involved about 15 schoolchildren. The median (25, 75 percentiles) twice-daily UV exposure values for all groups was 5.49 (3.59, 8.00) standard erythemal doses (SEDs), where 1 SED is defined as effective 100 Jm(-2) when weighted with the CIE erythemal response function. Exposure ratio (ER) is defined as the ratio between the personal dose on a selected body site and the corresponding ambient dose received on a horizontal plane during the same exposure period. The median (25, 75 percentiles) ER value for all groups in the study was 5.9% (4.1, 8.7).


Subject(s)
Radiation Dosage , Sunlight , Ultraviolet Rays , Child , Humans , Radiation Monitoring/instrumentation , Schools , Seasons , Spain
14.
Curr Protein Pept Sci ; 13(8): 816-30, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23305367

ABSTRACT

Diseases that result from infection are, in general, a consequence of specific interactions between a pathogenic organism and the cells. The study of host-pathogen interactions has provided insights for the design of drugs with therapeutic properties. One area that has proved to be promising for such studies is the constituted by carbohydrates which participate in biological processes of paramount importance. On the one hand, carbohydrates have shown to be information carriers with similar, if not higher, importance than traditionally considered carriers as amino acids and nucleic acids. On the other hand, the knowledge on molecular recognition of sugars by lectins and other carbohydrate-binding proteins has been employed for the development of new biomedical strategies. Biophysical techniques such as X-Ray crystallography and NMR spectroscopy lead currently the investigation on this field. In this review, a description of traditional and novel NMR methodologies employed in the study of sugar-protein interactions is briefly presented in combination with a palette of NMR-based studies related to biologically and/or pharmaceutically relevant applications.


Subject(s)
Carbohydrate Metabolism , Drug Design , Magnetic Resonance Spectroscopy/methods , Proteins/metabolism , Disease , Health , Humans , Protein Binding , Proteins/chemistry
15.
Photodermatol Photoimmunol Photomed ; 27(6): 311-7, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22092735

ABSTRACT

BACKGROUND: The purpose of this study is to quantify ultraviolet (UV) exposure of several groups of amateur athletes in their training or recreational schedules. METHODS: The athletes were monitored using dosimeters (VioSpor).The study took place in Valencia, Spain, from May to July 2010, and involved a group of 10 mountaineers, four tennis players and five runners. RESULTS: The mean daily personal UV exposure for mountaineers was 9.48 ± 3.23 standard erythema dose (SED). The tennis players received a mean of 10.65 ± 1.57 SED for every 2 days of training, and the runners received a mean of 7.62 ± 4.28 SED for every 5 days of training. CONCLUSION: Mountaineers received a higher dose of UV exposure and have a higher exposure ratio than the tennis players, probably because they spent more time outdoors. However, the runners received a low dose of UV exposure, perhaps because their training takes place in the evening. Mean daily UV exposure of the mountaineers and tennis players exceeded 5 SED, which means that, in the case of non-sun-adapted skin type III and the non-use of sun protection, erythema may be induced in these subjects. Accordingly, it is necessary to encourage the use of high protection sunscreens and protective clothing, and to avoid UV exposure in the hottest part of the day.


Subject(s)
Athletes , Running , Tennis , Ultraviolet Rays/adverse effects , Female , Humans , Male , Protective Clothing , Radiometry/methods , Spain , Sunscreening Agents/pharmacology , Time Factors
16.
Photochem Photobiol Sci ; 10(4): 523-30, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21180746

ABSTRACT

To quantify schoolchildren's exposure to ultraviolet erythemal radiation (UVER), personal dosimeters (VioSpor) were used to measure biologically effective ultraviolet (UV) radiation received in the course of their daily school activities. The study took place in two primary schools in Valencia (39°28'N), Spain, for several weeks from March 2008 until May 2009, with two age groups (6-8 years and 10-11 years) and involved about 47 schoolchildren. The median daily UV exposure values for all age groups and solar height intervals considered in the study ranged from 1.31 to 2.11 standard erythemal doses (SEDs). Individual UV exposure was analyzed as a function of age, gender and dosimeter position. Significant statistical differences were found between different age groups, with the younger age group receiving higher statistically significant UVER exposure. It was also found that boys received significantly higher UVER exposure than girls. It was also noted that shoulder dosimeters registered higher readings than wrist dosimeters. Exposure ratio (ER) is defined as the ratio between the personal dose on a selected anatomical site and the corresponding ambient dose on a horizontal plane. The median ER for all age groups and solar height intervals in the study range from 4.5% to 10.7%, with higher values at lower solar heights.


Subject(s)
Radiation Monitoring , Ultraviolet Rays , Age Factors , Child , Female , Humans , Male , Sex Factors , Spain , Sunlight
17.
Biochemistry ; 49(40): 8779-93, 2010 Oct 12.
Article in English | MEDLINE | ID: mdl-20825165

ABSTRACT

Predominantly, rice Os3BGlu7 operates as a ß-d-glucosidase (EC 3.2.1.21), while barley HvBII acts as a ß-d-mannosidase (EC 3.2.1.25). Saturation transfer difference nuclear magnetic resonance (STD NMR) and transferred nuclear Overhauser effect (trNOE) spectroscopy in conjunction with quantum mechanics/molecular mechanics (QM/MM) modeling and docking at the 6-31+G* level were used to investigate binding of S- and O-linked gluco- and manno-configured aryl-ß-d-glycosides to Os3BGlu7 and HvBII. Kinetic analyses with 4-nitrophenyl ß-d-thioglucoside (4NP-S-Glc) and 4-nitrophenyl ß-d-thiomannoside (4NP-S-Man) indicated that the inhibitions were competitive with apparent K(i) constants of 664 and 710 µM for Os3BGlu7 and 95 and 266 µM for HvBII, respectively. The STD NMR and trNOESY experiments revealed that 4NP-S-Glc and 4NP-S-Man bound weakly in (4)C(1) conformations to Os3BGlu7; 4NP-S-Glc adopted (3)S(5) (B(3,O)) or (1)S(3) ((1,4)B) conformations, and 4NP-S-Man preferred (4)C(1) geometry, when bound to HvBII. The QM modeling and docking, based on GLIDE scores, predicted that 4NP-O-Glc, 4NP-O-Man, and 4NP-S-Man bound preferentially in (1)S(3) geometries to both enzymes, contrary to 4NP-S-Glc that could also adopt a (4)C(1) conformation, although in a "flipped-down" ring position. The experimental and computational data suggested that in glycoside recognition and substrate specificity of Os3BGlu7 and HvBII, a combination of the following determinants is likely to play key roles: (i) the inherent conformational and spatial flexibilities of gluco- and manno-configured substrates in the enzymes' active sites, (ii) the subtle differences in the spatial disposition of active site residues and their capacities to form interactions with specific groups of substrates, and (iii) the small variations in the charge distributions and shapes of the catalytic sites.


Subject(s)
Glycosides/metabolism , Hordeum/enzymology , Mannosides/metabolism , Oryza/enzymology , beta-Glucosidase/metabolism , beta-Mannosidase/metabolism , Glycosides/chemistry , Hordeum/chemistry , Mannosides/chemistry , Models, Molecular , Nuclear Magnetic Resonance, Biomolecular , Oryza/chemistry , Protein Binding , Substrate Specificity , beta-Glucosidase/chemistry , beta-Mannosidase/chemistry
18.
Photochem Photobiol ; 86(3): 716-21, 2010.
Article in English | MEDLINE | ID: mdl-20158673

ABSTRACT

UV exposure is considered to be one of the most important risk factors in skin cancers, mainly in outdoor occupational or recreational activities. Outdoor athletes such as cyclists receive regular and significant solar UV erythemal radiation (UVER). The aim of this work was to quantify UVER exposure of amateur cyclists over the course of several days in their training schedules. To quantify UVER exposure of this group, dosimeters (Viospor) were attached at the top of the helmet in the course of their training. The study took place in Valencia, Spain, in June to July 2008 and February to March 2009, and involved a group of five cyclists over a period of 4 days for each period. The mean 2-day personal UV exposure was 32.24 +/- 4.14 SED (standard erythema dose) in summer and 11.30 +/- 5.36 SED in the winter period. One SED is defined as an effective radiant exposure of 100 J m(-2) when weighted with the International Commission on Illumination (CIE) erythemal response function. The mean exposure ratio (ER) of cyclists was 0.37 +/- 0.04 in summer and 0.40 +/- 0.11 in winter. The cyclists received the highest UVER exposure in the summer period, but in both training periods UVER exposure was in excess of occupational and recreational guidelines, indicating that protective measures are very necessary.


Subject(s)
Bicycling , Environmental Exposure/analysis , Ultraviolet Rays/adverse effects , Environmental Exposure/standards , Erythema/etiology , Humans , Radiation Dosage , Seasons , Spain , Time Factors
19.
Photochem Photobiol ; 85(6): 1468-73, 2009.
Article in English | MEDLINE | ID: mdl-19709385

ABSTRACT

UVexposure is considered to be one of the most important risk factors in skin cancers, mainly in outdoor occupational activities. Outdoor workers receive regular and significant solar UV erythemal radiation (UVER). To quantify the UVER exposure of certain groups of workers, dosimeters are used to measure the biologically effective UV radiation received in the course of their daily work. Two groups of outdoor workers, composed of gardeners and lifeguards, were measured for UVER exposure using sensitive spore-film filter-type personal dosimeters (Viospor). The study took place in Valencia, Spain, in June and July 2008, and involved one group of four gardeners and another of five beach lifeguards for a period of 4 and 6 days, respectively. The gardeners' mean UV exposure was 4.13 +/- 0.60 SED day(-1), where 1 SED is defined as effective 100 J m(-2) when weighted with the CIE erythemal response function, whereas the lifeguards received 11.43 +/- 2.15 SED day(-1). The mean exposure ratio (ER) relative to ambient of gardeners was 0.09 +/- 0.01 and for lifeguards was 0.27 +/- 0.05. ER is defined as the ratio between the personal dose on a selected anatomical site and the corresponding ambient dose on a horizontal plane during the same exposure period. The lifeguards received the highest UVER exposure, although both groups had measured UVER exposure in excess of occupational guidelines, indicating that protective measures are necessary.


Subject(s)
Occupational Exposure , Radiation Monitoring , Ultraviolet Rays , Bathing Beaches/statistics & numerical data , Female , Gardening/statistics & numerical data , Humans , Male , Occupational Exposure/statistics & numerical data , Spain , Sunlight
20.
Photochem Photobiol ; 85(5): 1245-53, 2009.
Article in English | MEDLINE | ID: mdl-19496991

ABSTRACT

Values of measured and modeled diffuse UV erythemal irradiance (UVER) for all sky conditions are compared on planes inclined at 40 degrees and oriented north, south, east and west. The models used for simulating diffuse UVER are of the geometric-type, mainly the Isotropic, Klucher, Hay, Muneer, Reindl and Schauberger models. To analyze the precision of the models, some statistical estimators were used such as root mean square deviation, mean absolute deviation and mean bias deviation. It was seen that all the analyzed models reproduce adequately the diffuse UVER on the south-facing plane, with greater discrepancies for the other inclined planes. When the models are applied to cloud-free conditions, the errors obtained are higher because the anisotropy of the sky dome acquires more importance and the models do not provide the estimation of diffuse UVER accurately.

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