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1.
Clin Oral Implants Res ; 35(2): 179-186, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37985190

RESUMEN

AIM: To compare measurements on images obtained by magnetic resonance imaging (MRI) and cone beam CT (CBCT) for height, width, and area in alveolar bone sites in human jaw specimens. MATERIAL AND METHODS: Forty edentulous alveolar posterior sites in human cadaver specimens were imaged using CBCT scanners, and with zero-echo-time MRI (ZTE-MRI). Semi-automatic volume registration was performed to generate representative coronal sections of the sites related to implant planning. ZTE-MRI sections were also presented after grayscale inversion (INV MRI). Three observers measured bone height, bone width 5 mm from the alveolar crest, and bone area stretching from the width measurement to the top of the alveolar crest in the images. Interobserver agreement was assessed by intra-class correlation coefficients (ICC). The measurements were analyzed using two-way repeated measures ANOVA factoring observer and image type. RESULTS: ICC was >0.95 for bone height, width, and bone area. No significant differences among observers (p = 0.14) or image type (p = 0.60) were found for bone height. For bone width, observer (p = 0.14) was not a significant factor, while ZTE-MRI produced width estimates that were significantly different and systematically smaller than CBCT-based estimates (p ≤ 0.001). Observer (p = 0.06) was not a significant factor regarding the bone area measurements, contrary to the imaging type where ZTE-MRI led to significantly smaller area estimates than CBCT (p ≤ 0.001). CONCLUSION: Bone height measurements were essentially equivalent using CBCT and MRI. This was found regardless of grayscale choice for the MRI. However, ZTE-MRI resulted in smaller estimates of bone width and area.


Asunto(s)
Implantes Dentales , Humanos , Proceso Alveolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Cadáver , Imagen por Resonancia Magnética
2.
Artículo en Inglés | MEDLINE | ID: mdl-37990981

RESUMEN

OBJECTIVES: Diagnostic imaging is crucial for implant dentistry. This review provides an up-to-date perspective on the application of digital diagnostic imaging in implant dentistry. METHODS: Electronic searches were conducted in PubMed focusing on the question 'when (and why) do we need diagnostic imaging in implant dentistry?' The search results were summarised to identify different applications of digital diagnostic imaging in implant dentistry. RESULTS: The most used imaging modalities in implant dentistry include intraoral periapical radiographs, panoramic views and cone beam computed tomography (CBCT). These are dependent on acquisition standardisation to optimise image quality. Particularly for CBCT, other technical parameters (i.e., tube current, tube voltage, field-of-view, voxel size) are relevant minimising the occurrence of artefacts. There is a growing interest in digital workflows, integrating diagnostic imaging and automation. Artificial intelligence (AI) has been incorporated into these workflows and is expected to play a significant role in the future of implant dentistry. Preliminary evidence supports the use of ionising-radiation-free imaging modalities (e.g., MRI and ultrasound) that can add value in terms of soft tissue visualisation. CONCLUSIONS: Digital diagnostic imaging is the sine qua non in implant dentistry. Image acquisition protocols must be tailored to the patient's needs and clinical indication, considering the trade-off between radiation exposure and needed information. growing evidence supporting the benefits of digital workflows, from planning to execution, and the future of implant dentistry will likely involve a synergy between human expertise and AI-driven intelligence. Transiting into ionising-radiation-free imaging modalities is feasible, but these must be further developed before clinical implementation.

3.
Lasers Med Sci ; 38(1): 101, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37060370

RESUMEN

To evaluate the applicability of photobiomodulation therapy (PBM-T) in the management of xerostomia and OM. Fifty-three patients with head and neck squamous cell carcinoma were randomized into two groups: Sham and PBM-T. The Sham group received artificial saliva and laser simulation, while the PBM-T group received artificial saliva and PBM-T. Xerostomia-related quality of life (QoL), the presence or absence of OM lesions, the decayed-missing-filled teeth (DMFT) index, and periodontal charts were evaluated. The results of the QoL questionnaire, DMFT index, and periodontal chart were analyzed with the Kruskal-Wallis test, followed by the Student-Newman-Keuls test, while OM findings were compared using the Mann-Whitney test. QoL scores significantly increased in the Sham group (p < 0.0001), denoting more severe xerostomia symptoms (p = 0.0074), and decreased in the PBM-T group, indicating no or very mild xerostomia. Higher grades of OM were found in the Sham group than the PBM-T group (p = 0.0001). There was no significant difference in DMFT index or periodontal charts between the groups (p > 0.05). PBM-T improved QoL in patients with head and neck cancer treated with radiotherapy, whether as radiation alone or as an adjunct to chemotherapy and surgery.


Asunto(s)
Neoplasias de Cabeza y Cuello , Terapia por Luz de Baja Intensidad , Estomatitis , Xerostomía , Humanos , Calidad de Vida , Saliva Artificial , Estomatitis/etiología , Estomatitis/radioterapia , Estomatitis/patología , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/radioterapia , Xerostomía/etiología , Xerostomía/radioterapia , Terapia por Luz de Baja Intensidad/métodos
4.
Acta Odontol Scand ; 81(3): 241-248, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36112428

RESUMEN

OBJECTIVES: To compare alveolar bone height and width measurements from zero-echo-time MRI (ZTE-MRI) and cone beam CT (CBCT), in human specimens. MATERIAL AND METHODS: Twenty posterior edentulous sites in human cadaver specimens were imaged with CBCT and ZTE-MRI. Bone height and width at 1, 3, 5, 7 and 9 mm from the top of the alveolar ridge was measured by two trained observers in cross-sections of a site where an implant was to be planned. Twenty percent of the sample was measured in duplicate to assess method error and intra-observer reproducibility (ICC). The differences between CBCT and ZTE-MRI measurements were compared (t-test). RESULTS: Inter- and intra-observer reproducibility was >0.90. The method error (average between observers) for bone height was 0.45 mm and 0.39 mm, and for bone width (average) was 0.52 mm and 0.80 mm (CBCT and ZTE-MRI, respectively). The majority of the bone measurement differences were statistically insignificant, except bone width measurements at 5 mm (p ≤ .05 for both observers). Mean measurement differences were not larger than the method error. CONCLUSION: ZTE-MRI is not significantly different from CBCT when comparing measurements of alveolar bone height and width.


Asunto(s)
Proceso Alveolar , Tomografía Computarizada de Haz Cónico , Humanos , Reproducibilidad de los Resultados , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/anatomía & histología , Tomografía Computarizada de Haz Cónico/métodos , Imagen por Resonancia Magnética , Cadáver
5.
Zoo Biol ; 42(4): 577-581, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36959717

RESUMEN

The golden lancehead (Bothrops insularis) is a critically endangered snake endemic to Queimada Grande Island, southeastern Brazil. Captive breeding programs are vital for the conservation of this species. This study evaluates the gestation of two females golden lanceheads using radiography and ultrasonography. The first female was collected on the island while reproductively active (late vitellogenesis or early pregnancy) and kept in captivity. This female gave birth to five neonates after an 8-month gestation period, which is longer than estimates based on specimens preserved in museums. The second female copulated in captivity in July and probably ovulated in October. In this case, no embryonic development was detected, and the female deposited 14 undeveloped eggs approximately 6 months after ovulation.


Asunto(s)
Bothrops , Femenino , Animales , Embarazo , Animales de Zoológico , Brasil
6.
J Oral Maxillofac Surg ; 79(12): 2499-2506, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34339622

RESUMEN

Several treatment protocols for medication-related osteonecrosis of the jaw (MRONJ) have been published. Despite the efficacy of surgical therapy of approximately 90% as primary therapy, the role of other agents, such as drug administration, should not be underestimated. Based on previous experience with osteoradionecrosis, the association of pentoxifylline and tocopherol has shown encouraging results in MRONJ patients. Despite the need for long-term use of the combination, compliance has been good. However, studies in breast cancer patients revealed that pentoxifylline can require dose reduction or discontinuation due to nausea and epigastric pain. Cilostazol has been used as a substitute for pentoxifylline in peripheral artery disease. Herein we report a case in which cilostazol replaced pentoxifylline at a dose of 100mg, 2 times/day with tocopherol 500UI, 2 times/day, in a 77-year-old female patient that could not tolerate pentoxifylline for the management of MRONJ. After an uneventful 22 months of follow-up, a cone-beam computed tomography revealed complete bone formation and no signs of recurrence. Cilostazol may be a useful and safe alternative to pentoxifylline as part of MRONJ management protocols.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos , Conservadores de la Densidad Ósea , Osteonecrosis , Osteorradionecrosis , Preparaciones Farmacéuticas , Anciano , Cilostazol , Femenino , Humanos , Osteonecrosis/inducido químicamente , Osteonecrosis/diagnóstico por imagen , Osteonecrosis/tratamiento farmacológico , Tocoferoles/uso terapéutico
7.
Molecules ; 26(24)2021 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-34946705

RESUMEN

The binding between anticancer drugs and double-stranded DNA (dsDNA) is a key issue to understand their mechanism of action, and many chemical methods have been explored on this task. Molecular docking techniques successfully predict the affinity of small molecules into the DNA binding sites. In turn, various DNA-targeted drugs are electroactive; in this regard, their electrochemical behavior may change according to the nature and strength of interaction with DNA. A carbon paste electrode (CPE) modified with calf thymus ds-DNA (CPDE) and computational methods were used to evaluate the drug-DNA intercalation of doxorubicin (DOX), daunorubicin (DAU), idarubicin (IDA), dacarbazine (DAR), mitoxantrone (MIT), and methotrexate (MTX), aiming to evaluate eventual correlations. CPE and CPDE were immersed in pH 7 0.1 mM solutions of each drug with different incubation times. As expected, the CPDE response for all DNA-targeted drugs was higher than that of CPE, evidencing the drug-DNA interaction. A peak current increase of up to 10-fold was observed; the lowest increase was seen for MTX, and the highest increase for MIT. Although this increase in the sensitivity is certainly tied to preconcentration effects of DNA, the data did not agree entirely with docking studies, evidencing the participation of other factors, such as viscosity, interfacial electrostatic interactions, and coefficient of diffusion.


Asunto(s)
Antineoplásicos/química , ADN/química , Sustancias Intercalantes/química , Simulación del Acoplamiento Molecular
8.
Microb Pathog ; 147: 104273, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32473391

RESUMEN

The present study was developed to characterize, at the species level, 34 strains of Aeromonas spp., previously isolated from stressed tambaqui fish (Colossoma macropomum), to elucidate virulence factors, as well as their antibiotic resistance profile. Amplification of the gyrB gene identified the strains as A. hydrophila, A. dhakensis, A. caviae, A. veronii and A. jandaei. Bacterial virulence was evaluated by enzymatic assays for phenotypical production of hemolysins, proteases and lipases followed by the search for genes codifying the enzymes ß-hemolysin, serine protease and lipase. Phenotypical production of virulence factors was diversified and proteolytic activity demonstrated to be a common expression among the strains. On the other hand, the lip gene encoding extracellular lipase was the most expressed. Furthermore, A. hydrophila was the most prevalent species isolated from tambaqui in our work.


Asunto(s)
Aeromonas , Characiformes , Infecciones por Bacterias Gramnegativas , Aeromonas/genética , Animales , Antibacterianos , Infecciones por Bacterias Gramnegativas/veterinaria , Virulencia
9.
AIDS Behav ; 23(12): 3375-3383, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31102107

RESUMEN

The objective of this cross-sectional survey was to assess the prevalence of psychoactive substance use (PSU) in people attending 11 French Sexual Transmitted Infection Centers, and to specify their profiles (PSU and link with risky sexual behaviors) using the ascending hierarchical clustering method. Among the 5220 individuals who completed the survey, 55.6% were men and the median age was 24 years [IQR: 20-31]. Among the participants, 2751 (52.7%) reported PSU at least once in their life. Ascending hierarchical clustering identified seven distinct profiles of participants based on their PSU. This study shows a high prevalence of PSU and alcohol consumption in this young population. Moreover, subgroup analysis allowed identifying groups of psychoactive substance users who presented specific risks or vulnerabilities and who should be priority targets for interventions, particularly sexual minority groups.


Asunto(s)
Heterosexualidad/estadística & datos numéricos , Uso de la Marihuana/epidemiología , Conducta Sexual/estadística & datos numéricos , Minorías Sexuales y de Género/estadística & datos numéricos , Trastornos Relacionados con Sustancias/epidemiología , Adolescente , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Estimulantes del Sistema Nervioso Central , Estudios Transversales , Femenino , Francia/epidemiología , Infecciones por VIH/epidemiología , Alucinógenos , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Asunción de Riesgos , Encuestas y Cuestionarios , Adulto Joven
10.
J Comput Chem ; 39(20): 1424-1432, 2018 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-29607518

RESUMEN

Quantum tunneling paths are important in reactions when there is a significant component of hydrogenic motion along the potential energy surface. In this study, variational transition state with multidimensional tunneling corrections are employed in the calculations of the thermal rate constants for hydrogen abstraction from the cis-CH3 OCHO by O (3 P) giving CH3 OCO + OH (R1) and CH2 OCHO + OH (R2). The structures and electronic energies are computed with the M06-2X method. Benchmark calculations with the CBSD-T approach give an enthalpy of reaction at 0 K for R1 (-2.8 kcal/mol) and R2 (-2.5 kcal/mol) which are in good agreement with the experiment, i.e. -2.61 and -1.81 kcal/mol. At the low and intermediate values of temperatures, small- and large-curvature tunneling dominate the kinetics of R1, which is the dominant path over the range of temperature from 250 to 1200 K. This study shows the importance of multidimensional tunneling corrections for both R1 and R2, for which the total rate constant at 298 K calculated with the CVT/µOMT method is 8.2 × 10-15 cm3 molecule-1 s-1 which agrees well with experiment value of 9.3 × 10-15 cm3 molecule-1 s-1 (Mori, Bull. Inst. Chem. Res. 1981, 59, 116). © 2018 Wiley Periodicals, Inc.

11.
ScientificWorldJournal ; 2018: 2878215, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30224902

RESUMEN

The objective of the research was to evaluate changes of dietetic functional mixed cerrado fruit jam (marolo, sweet passion fruit, and soursop) processed in a vacuum pot and stored for 180 days in BODs at 25°C and 35°C. The parameters evaluated were pH, soluble solids (SS), titratable acidity (TA), total sugars (TS), total carotenoids (TC), total phenolics (TP), vitamin C, antioxidant activity (DPPH), and microbiological analysis. There was a significant effect of storage time on pH, SS, TA, TC, TS, and TP. Vitamin C and DPPH showed an effect for the temperature x storage time interaction. Statistical models are not adjusted for pH and SS, presenting an average of 4.15 and 61%, respectively. Carotenoids decreased up to105 days; total sugars increased up to 105 days. The TP, vitamin C, and DPPH, at the temperatures evaluated, showed a decrease up to 105 days. Yeasts and filamentous fungi were not detected.


Asunto(s)
Annona/microbiología , Dietética/normas , Almacenamiento de Alimentos/normas , Alimentos en Conserva/microbiología , Alimentos en Conserva/normas , Passiflora/microbiología , Annona/química , Ácido Ascórbico/análisis , Fenómenos Químicos , Dietética/métodos , Conservación de Alimentos/métodos , Conservación de Alimentos/normas , Almacenamiento de Alimentos/métodos , Calor/efectos adversos , Passiflora/química , Factores de Tiempo
12.
J Appl Microbiol ; 121(3): 811-20, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27159339

RESUMEN

AIM: The objective of this study was to identify and characterize lactic acid bacteria isolated from human milk, with an emphasis on their probiotic properties. METHODS AND RESULTS: The strains were tested for their ability to inhibit growth of Enterococcus faecalis, Salmonella enterica subsp. enterica serotype Enteritidis, Listeria monocytogenes, Staphylococcus aureus and Escherichia coli, as well as for susceptibility to antimicrobial agents and for acid pH and bile salt tolerance. Gram-positive and catalase-negative were selected and identified as Enterococcus (83·3%) after sequencing the 16S rDNA gene. All the isolates inhibited growth of Ent. faecalis and S. serotype Enteritidis, 97% inhibited growth of L. monocytogenes and Staph. aureus and 78·8% inhibited growth of E. coli. Most of the isolates were resistant to gentamicin (50%) and vancomycin (47%). Twelve isolates grew when subjected to pH 3·0 and 0·1% bile salts. At lower pH (2·5-2·0), Ent. faecalis F1 and Weissella confusa F8 were more efficient. CONCLUSION: It was possible to isolate from human milk the lactic acid bacteria with potential for use as probiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactic acid bacteria isolated of nursing mothers have probiotic properties.


Asunto(s)
Bacterias/aislamiento & purificación , Leche Humana/microbiología , Probióticos/aislamiento & purificación , Bacterias/clasificación , Bacterias/genética , Femenino , Humanos , Ácido Láctico/metabolismo , Probióticos/clasificación , Probióticos/metabolismo
13.
Front Toxicol ; 6: 1368320, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38577564

RESUMEN

Perfluorooctanoic acid (PFOA) is a persistent environmental contaminant that can accumulate in the human body due to its long half-life. This substance has been associated with liver, pancreatic, testicular and breast cancers, liver steatosis and endocrine disruption. PFOA is a member of a large group of substances also known as "forever chemicals" and the vast majority of substances of this group lack toxicological data that would enable their effective risk assessment in terms of human health hazards. This study aimed to derive a health-based guidance value for PFOA intake (ng/kg BW/day) from in vitro transcriptomics data. To this end, we developed an in silico workflow comprising five components: (i) sourcing in vitro hepatic transcriptomics concentration-response data; (ii) deriving molecular points of departure using BMDExpress3 and performing pathway analysis using gene set enrichment analysis (GSEA) to identify the most sensitive molecular pathways to PFOA exposure; (iii) estimating freely-dissolved PFOA concentrations in vitro using a mass balance model; (iv) estimating in vivo doses by reverse dosimetry using a PBK model for PFOA as part of a quantitative in vitro to in vivo extrapolation (QIVIVE) algorithm; and (v) calculating a tolerable daily intake (TDI) for PFOA. Fourteen percent of interrogated genes exhibited in vitro concentration-response relationships. GSEA pathway enrichment analysis revealed that "fatty acid metabolism" was the most sensitive pathway to PFOA exposure. In vitro free PFOA concentrations were calculated to be 2.9% of the nominal applied concentrations, and these free concentrations were input into the QIVIVE workflow. Exposure doses for a virtual population of 3,000 individuals were estimated, from which a TDI of 0.15 ng/kg BW/day for PFOA was calculated using the benchmark dose modelling software, PROAST. This TDI is comparable to previously published values of 1.16, 0.69, and 0.86 ng/kg BW/day by the European Food Safety Authority. In conclusion, this study demonstrates the combined utility of an "omics"-derived molecular point of departure and in silico QIVIVE workflow for setting health-based guidance values in anticipation of the acceptance of in vitro concentration-response molecular measurements in chemical risk assessment.

14.
J Morphol ; 285(9): e21766, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39169635

RESUMEN

Hemiphractids have a singular mode of reproduction that involves maternal care. The Andean-endemic Gastrotheca marsupiata species group includes direct-developing and tadpole-bearing species, the latter trait being unique among Gastrotheca. Larval morphology has proven to be a valuable source of evidence to understand the taxonomy and evolution of frogs but remains understudied in Hemiphractids. Herein, we redescribe the larval cranium of G. espeletia, G. gracilis, G. marsupiata, G. peruana, G. pseustes, and G. riobambae, and describe those of G. aureomaculata, G. chrysosticta, G. litonedis, G. monticola and G. psychrophila. Additionally, based on the data gathered, we explore their phylogenetic significance, expanding the knowledge regarding Gastrotheca larval internal morphology. We suggest that the presence of the posterolateral process of crista parotica, the concave palatoquadrate, the quadratoorbital commissure, and the proximal commissures II and III are putative synapomorphies for Gastrotheca. Furthermore, we suggest the long pseudopterygoid process as a putative synapomorphy for Hemiphractyidae.


Asunto(s)
Anuros , Evolución Biológica , Larva , Cráneo , Animales , Larva/anatomía & histología , Anuros/anatomía & histología , Cráneo/anatomía & histología , Filogenia
15.
Rev Lat Am Enfermagem ; 32: e4191, 2024.
Artículo en Inglés, Español, Portugués | MEDLINE | ID: mdl-38865557

RESUMEN

OBJECTIVE: to evaluate the usability of the ROBOVID mobile application for health education about COVID-19. METHOD: methodological study with an applied quantitative approach, developed with 21 adults, using an electronic form. Usability was assessed using the System Usability Scale. The Statistical Package for the Social Sciences software was used to analyze the data. RESULTS: the overall average score on the System Usability Scale questionnaire was 87.3, which classifies the usability of the ROBOVID application as the best achievable. Furthermore, the application has high scores for ease of memorization, user satisfaction and ease of getting to know the system, as well as excellent scores for absence of errors and speed in carrying out the tasks set. CONCLUSION: the ROBOVID application complies with the principles of usability in terms of efficiency, effectiveness and satisfaction in the evaluation of end users, showing that the application meets consumer needs in terms of its functionalities, demonstrating its viability in terms of the initial objectives. (1) ROBOVID was considered better achievable on the SUS scale by the participants. (2) The ROBOVID app meets the user's needs in terms of its functions. (3) ROBOVID helps individuals to take care of themselves and prevent COVID-19. (4) The ROBOVID app was evaluated as a useful, didactic and functional tool.


Asunto(s)
COVID-19 , Educación en Salud , Aplicaciones Móviles , Humanos , COVID-19/prevención & control , Adulto , Femenino , Masculino , Educación en Salud/métodos , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto Joven
16.
Artículo en Inglés | MEDLINE | ID: mdl-39261150

RESUMEN

Chimeric antigen receptor T-cell therapy represents an innovative approach to immunotherapy and currently stands out, particularly for oncohematological patients refractory to traditional treatments. Ongoing trials are further expanding its clinical use for new oncological and non-oncological indications, potentially leading to newer treatment options soon. This new approach, however, also presents challenges, including cardiovascular toxicity. Little is reported in pivotal studies, and some recent retrospective observations suggest a non-negligible incidence of side effects with presentation ranging from mild adverse cardiovascular events to fatal complications in which, in most cases, there is a direct or indirect association with cytokine release syndrome. In this literature review, the hypotheses of an important interface between cytokine release syndrome and cardiotoxicity by chimeric antigen receptor T-cell therapy will be addressed, as will current knowledge about risk factors for cardiotoxicity and recommendations for pre-therapy evaluation, post-infusion monitoring and clinical management of these complications.

17.
Mem Inst Oswaldo Cruz ; 108(1): 65-72, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23440117

RESUMEN

Multiple locus sequence typing (MLST) was undertaken to extend the genetic characterization of 29 isolates of Bacillus cereus and Bacillus thuringiensis previously characterized in terms of presence/absence of sequences encoding virulence factors and via variable number tandem repeat (VNTR). Additional analysis involved polymerase chain reaction for the presence of sequences (be, cytK, inA, pag, lef, cya and cap), encoding putative virulence factors, not investigated in the earlier study. MLST analysis ascribed novel and unique sequence types to each of the isolates. A phylogenetic tree was constructed from a single sequence of 2,838 bp of concatenated loci sequences. The strains were not monophyletic by analysis of any specific housekeeping gene or virulence characteristic. No clear association in relation to source of isolation or to genotypic profile based on the presence or absence of putative virulence genes could be identified. Comparison of VNTR profiling with MLST data suggested a correlation between these two methods of genetic analysis. In common with the majority of previous studies, MLST was unable to provide clarification of the basis for pathogenicity among members of the B. cereus complex. Nevertheless, our application of MLST served to reinforce the notion that B. cereus and B. thuringiensis should be considered as the same species.


Asunto(s)
Bacillus cereus/genética , Bacillus thuringiensis/genética , Repeticiones de Minisatélite/genética , Tipificación de Secuencias Multilocus , Bacillus cereus/patogenicidad , Bacillus thuringiensis/patogenicidad , Brasil , Genotipo , Filogenia , Reacción en Cadena de la Polimerasa , Factores de Virulencia/genética
18.
Zootaxa ; 3683: 427-38, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25250462

RESUMEN

The chondrocranium and hyobranchial morphology are described for the tadpoles of five species of Proceratophrys Miranda-Ribeiro. The chondrocranium of P. appendiculata, P boiei, P laticeps and P. tupinamba are very similar and can be distinguished from that of P. cristiceps by: 1) less developed processus muscularis; 2) thinner palatoquadrate; 3) broadest ethmoidal region; 4) longer cornua trabeculae; and 5) morphology f the suprarostral cartilages. A morphological variation among Proceratophrys boiei is described. It reveals the existence of at least three distinct evolutionary lineages under this name. A brief comparison with other cycloramphid species is also provided.


Asunto(s)
Anuros/anatomía & histología , Anuros/clasificación , Cartílago/anatomía & histología , Branquias/anatomía & histología , Filogenia , Cráneo/anatomía & histología , Animales , Anuros/crecimiento & desarrollo , Cartílago/crecimiento & desarrollo , Branquias/crecimiento & desarrollo , Larva/anatomía & histología , Larva/clasificación , Larva/crecimiento & desarrollo , Cráneo/crecimiento & desarrollo
19.
Zootaxa ; 3682: 277-304, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25243288

RESUMEN

We describe two new species of Proceratophrys allied to the P. appendiculata species complex by the presence of single and long palpebral appendages and a triangular rostral appendage. Proceratophrys izecksohni sp. nov. is characterized by having small to medium size (SVL 32.1-54.2 mm in males), elongated hindlimbs (thigh length plus tibia length corresponding to more than 90% of snout-vent length), a broad head (head width corresponding to 55% of the snout-vent length), and by the light brown gular region and a cream colored ventral surface with scattered brown dots. Proceratophrys belzebul sp. nov. is characterized by its medium size (SVL 40.5-51.3 mm in males), by the absence of contact between the nasals bones and between the nasals and frontoparietals, by a very reduced iliac projection, by having frontoparietal bones very depressed and broad rostrally, by the smooth surface of the squamosal and nasal, by shallow, inconspicuous ventral pits on the maxillae, and by the females presenting the gular region dark brown. The two new species were previously confused with P. appendiculata for which we provide a new diagnosis. A molecular analysis based on mitochondrial and nuclear genes recovers a monophyletic Proceratophrys with high support, and the two new species in a clade with P. appendiculata and P. tupinamba. The data also reinforce the idea that the species groups presently admitted to the genus are not monophyletic.


Asunto(s)
Anuros/anatomía & histología , Anuros/clasificación , Filogenia , Animales , Anuros/genética , Brasil , Núcleo Celular/genética , Femenino , Masculino , Proteínas Mitocondriales/genética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Especificidad de la Especie
20.
J Mol Model ; 29(2): 48, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36658290

RESUMEN

The equilibrium structures of BeO clusters and Be,Ti-decorated boranes were computed with the ωB97X-D method and the 6-31G + (2d,2p) and aug-cc-pVTZ basis sets to study their intermolecular interactions with hydrogen molecules. Thermochemical and molecular properties such as the harmonic vibrational frequency, dipole and quadrupole moments, and atomic charges are employed to understand the attractive interactions that control the adsorption process. Comparison of molecular properties and atomic charges of the studied compounds before and after H2 molecule adsorption shows that most of the interactions among the BeO clusters and boranes with H2 molecules constitute a combination of dispersion, electrostatic, and weak charge transfer interactions. Calculated values of Hirschfeld atomic charges and ΔEe (in parenthesis) (BeO)4.8H2 (0.028 e and -2.0 kcal.mol-1), (BeO)2.12H2 (0.030 e and -2.8 kcal.mol-1), B6Ti3.10H2 (0.045 e and -15.4 kcal.mol-1), and B6Ti3+.10H2 (0.058 e and -15.3 kcal.mol-1) show qualitative correlation between hydrogen atomic charges and electronic energy of hydrogen interaction. The ωB97X-D/6-31 + G(2d,2p) values of Gibbs free energy at 298.15 K for (BeO)4.8H2 B2H4Ti.4H2 and B6Ti3.10H2 clusters are equal to -5.0, -4.9, and -5.1 kcal.mol-1, respectively, which are within the range of energy parameters of materials that could be employed in hydrogen storage tanks for light vehicles.

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