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1.
J Clin Periodontol ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956881

RESUMEN

AIM: To compare the subgingival microbiota of patients receiving supportive periodontal care (SPC) with and without subgingival instrumentation, over 2 years. MATERIALS AND METHODS: This study was a randomized clinical trial that included 62 participants (50.97 ± 9.26 years old; 40 females) who completed non-surgical periodontal therapy. Participants were randomly assigned to receive oral prophylaxis with oral hygiene instructions alone (test) or in combination with subgingival instrumentation (control) during SPC. Pooled subgingival biofilm samples were obtained from four sites per patient at SPC baseline and at 3, 6, 12, 18, and 24 months. Real-time polymerase chain reaction was used for absolute quantification of Eubacteria and the target bacteria Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. Data were analysed using generalized estimating equations, taking into consideration the clustering of observations within individuals. RESULTS: No significant differences were found between the experimental groups regarding the mean counts of Eubacteria and target bacteria, as well as the periodontal parameters at the sampled sites. Although significant variability in bacterial counts was present during SPC, all counts after 2 years were not statistically different from those at baseline. Bacterial counts were associated with the presence of plaque, bleeding on probing, mean probing depth ≥3 mm, and follow-up period. CONCLUSIONS: SPC with or without subgingival instrumentation can result in comparable subgingival microbiological outcomes. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov: NCT01598155 (https://clinicaltrials.gov/study/NCT01598155?intr=supragingival%20control&rank=4#study-record-dates).

2.
Chaos ; 34(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949533

RESUMEN

In this paper, we propose a novel control approach for opinion dynamics on evolving networks. The controls modify the strength of connections in the network, rather than influencing opinions directly, with the overall goal of steering the population toward a target opinion. This requires that the social network remains sufficiently connected, the population does not break into separate opinion clusters, and that the target opinion remains accessible. We present several approaches to address these challenges, considering questions of controllability, instantaneous control, and optimal control. Each of these approaches provides a different view on the complex relationship between opinion and network dynamics and raises interesting questions for future research.

3.
J Helminthol ; 98: e7, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38225903

RESUMEN

Semperula wallacei (Issel, 1874) is a species of terrestrial slug that occurs in southeast China and the Pacific Basin and is the only species of its genus that occurs beyond the Oriental region and to the east of Wallace's line in the Australian region, where it has probably been introduced. In this study, we report for the first time S. wallacei as an intermediate host for Angiostrongylus cantonensis (Chen, 1935) based on histological and molecular analyses of slugs from Tuamasaga, Samoa, deposited at the Medical Malacological Collection (Fiocruz-CMM). DNA was obtained from the deparafinized tissues scraped from specimen slides. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) targeted to the internal transcribed spacer 2 (ITS2) region were carried out using the restriction enzyme Cla I. The RFLP profile observed for our larval specimen of S. wallacei was identical to the profile previously established for A. cantonensis, demonstrating that S. wallacei can be naturally infected with A. cantonensis and is likely to be an intermediate host for this parasitic nematode species in the field. The potential for geographical range expansion of S. wallacei in the Pacific Basin, its small size, and the general role of veronicellids as crop pests and hosts of nematodes, indicate the significance of S. wallacei as an invasive species in the Pacific Basin. Our work also highlights the importance of biological collections for investigating the environmental impact of invasive species on agriculture, public health, and biodiversity conservation.


Asunto(s)
Angiostrongylus cantonensis , Angiostrongylus , Gastrópodos , Nematodos , Infecciones por Strongylida , Animales , Angiostrongylus cantonensis/genética , Australia , Moluscos/parasitología , Especies Introducidas , Infecciones por Strongylida/veterinaria , Infecciones por Strongylida/parasitología
4.
Osteoporos Int ; 34(12): 2003-2012, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37658999

RESUMEN

Renal osteodystrophy (ROD) starts early and progresses with further loss of kidney function in patients with chronic kidney disease (CKD). There are four distinct types of ROD based on undecalcified bone biopsy results. Adynamic bone disease and osteomalacia are the predominant forms of low bone turnover, while hyperparathyroid bone disease and mixed uremic osteodystrophy (MUO) are typically associated with high bone turnover. MUO is a prevalent but poorly described pathology that demonstrates evidence of osteomalacia on top of the high bone formation/resorption. The prevalence of MUO ranges from 5 to 63% among different studies. The pathogenesis of MUO is multi-factorial. Altered phosphate homeostasis, hypocalcemia, vitamin D deficiency, increased FGF-23, interleukins 1 and 6, TNF-α, amyloid, and heavy metal accumulation are the main inducers of MUO. The clinical findings of MUO are usually non-specific. The use of non-invasive testing such as bone turnover markers and imaging techniques might help to suspect MUO. However, it is usually impossible to precisely diagnose this condition without performing bone biopsy. The principal management of MUO is to control the maladaptive hyperparathyroidism along with correcting any nutritional mineral deficiencies that may induce mineralization defect. MUO is a common but still poorly understood bone pathology category; it demonstrates the complexity and difficulty in understanding ROD. A large prospective bone biopsy-based studies are needed for better identification as proper diagnosis and management would improve the outcome of patients with MUO.


Asunto(s)
Enfermedades Óseas Metabólicas , Resorción Ósea , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica , Osteomalacia , Insuficiencia Renal Crónica , Humanos , Osteomalacia/complicaciones , Estudios Prospectivos , Huesos , Insuficiencia Renal Crónica/complicaciones , Enfermedades Óseas Metabólicas/complicaciones , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/complicaciones
5.
J Helminthol ; 96: e86, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36454026

RESUMEN

The giant African land snail, Achatina fulica, is an important invasive species in many countries, where it causes losses in biodiversity and agriculture, as well as impacting the health of both humans and animals, as the intermediate host of medically important nematodes. The present study is based on a comprehensive review of the literature on the nematodes that have been found in association with A. fulica, worldwide. We searched a number of different databases and used the findings to investigate the methods used to extract and identify the nematodes, their larval stages, and environment and collecting procedures of the infected molluscs. Between 1965 and 2021, 11 nematode species were recorded in association with A. fulica in 21 countries. Most of the studies recorded associations between A. fulica and Angiostrongylus cantonensis, which causes cerebral angiostrongyliasis in humans and Aelurostrongylus abstrusus, which provokes pneumonia in felines. The nematodes were extracted primarily by artificial digestion with hydrochloric acid or pepsin, and identified based on their morphology or through experimental infection to obtain the adult. In most cases, the nematodes were at larval stage L3, and the infected A. fulica were collected from anthropogenic environments. The results demonstrate the importance of A. fulica as a host of nematodes of medical and veterinary importance, as well the contribution of anthropogenic environments to the occurrence of the parasites, and give information about the different methods used to collect and identify the nematodes found associated with this species.


Asunto(s)
Angiostrongylus cantonensis , Infecciones por Strongylida , Adulto , Humanos , Animales , Gatos , Aves , Alimentos , Infecciones por Strongylida/veterinaria , Larva , Caracoles
6.
Ann Pharm Fr ; 79(3): 230-243, 2021 May.
Artículo en Francés | MEDLINE | ID: mdl-33159849

RESUMEN

Radiopharmaceuticals are commonly used in children in nuclear medicine. Because of physiological differences in growing children and their radiosensitivity, precautions must be taken throughout the medication use process. The aim of this work is to propose recommendations, under the aegis of the Société française de radiopharmacie (SoFRa), for each subsystem of the process, in order to ensure the safety of pediatric patients. Furthermore, an analysis of two surveys on diagnostic radiopharmaceuticals dosage used in different nuclear medicine departments in France is detailed. Recommendations for therapeutic radiopharmaceuticals are also provided. Specificities of the preparation for pediatric patients are discussed through the example of the radiopharmaceuticals for lung perfusion scintigraphy. The preparation of individual dose and administration are also described. In nuclear medicine, radiopharmacist's expertise is essential for patient safety. A multidisciplinary approach is necessary to secure pediatric radiopharmaceutical use process.


Asunto(s)
Pediatría , Radiofármacos , Niño , Francia , Humanos
7.
Ann Pharm Fr ; 78(1): 76-86, 2020 Jan.
Artículo en Francés | MEDLINE | ID: mdl-31796264

RESUMEN

The Radiopharmaceutical Health Products circuit or RHP (radiopharmaceutical drugs, radiopharmaceutical preparation and radioactive implantable medical devices) is a complex process that nowadays requires computerization. This circuit must be in accordance with both the legislation on medicinal products and the legislation on artificial radioelements. It is acknowledged that computerization of the circuit; possibly different within each organization, provides assistance to stakeholders: pharmaceutical analysis of prescription, pharmaceutical preparation and preparation of doses to be dispensed and waste management for example. The software also allows real-time monitoring of the activity and traceability of the various pharmaceutical processes. In addition, they are generally interfaced with equipment used routinely: dose calibrator, dose dispensing equipment. In the absence of any legislation for these software products, which are not considered either as medical devices or as software to assist prescription or dispensation, a working group, under the aegis of the Société Française de Radiopharmacie (SoFRa), has written a minimum set of specifications for these radiopharmaceutical software products. The analyses of the risk maps of different hospital structures allowed a global analysis and synthesis of the different processes, settings, interfaces and requirements for the proper use of these software. The specifications include the very specific requirements of radiopharmacy (notion of radioactive decay, complex preparations with chemical synthesis, traceability.) and will allow software publishers to propose tools adapted to our practice and the RHP circuit.


Asunto(s)
Radiofármacos , Programas Informáticos , Certificación , Sistemas de Computación , Relación Dosis-Respuesta en la Radiación , Humanos , Farmacias/organización & administración , Residuos Radiactivos , Radiofármacos/administración & dosificación , Radiofármacos/efectos adversos , Programas Informáticos/normas , Administración de Residuos
8.
J Helminthol ; 93(6): 775-777, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30205852

RESUMEN

Many molluscs may be infected with angiostrongylid larvae. Following the histopathological diagnosis of abdominal angiostrongyliasis in a grape farmer from southern Brazil, molluscs in the area were investigated. During a nocturnal search, 245 specimens of slugs were collected and identified as the invasive Chinese slug Meghimatium pictum. Angiostrongylus costaricensis worms were recovered from mice that were experimentally infected with larvae obtained from 11 (4.5%) of the molluscs. This study presents the first report of M. pictum being identified as an intermediate host for A. costaricensis. Most of the slugs were collected from grape plants, which suggests that transmission may be associated with grape consumption.


Asunto(s)
Angiostrongylus/aislamiento & purificación , Gastrópodos/parasitología , Infecciones por Strongylida/parasitología , Vitis/parasitología , Angiostrongylus/clasificación , Angiostrongylus/genética , Animales , Brasil , Gastrópodos/clasificación , Humanos , Especies Introducidas , Ratones , Infecciones por Strongylida/transmisión
9.
Arch Toxicol ; 92(7): 2275-2295, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29869127

RESUMEN

3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy") is a widespread drug of abuse with known neurotoxic properties. The present study aimed to evaluate the differential toxic effects of MDMA in adolescent and aged Wistar rats, using doses pharmacologically comparable to humans. Adolescent (post-natal day 40) (3 × 5 mg/kg, 2 h apart) and aged (mean 20 months old) (2 × 5 mg/kg, 2 h apart) rats received MDMA intraperitoneally. Animals were killed 7 days later, and the frontal cortex, hippocampus, striatum and cerebellum brain areas were dissected, and heart, liver and kidneys were collected. MDMA caused hyperthermia in both treated groups, but aged rats had a more dramatic temperature elevation. MDMA promoted serotonergic neurotoxicity only in the hippocampus of aged, but not in the adolescents' brain, and did not change the levels of dopamine or serotonin metabolite in the striatum of both groups. Differential responses according to age were also seen regarding brain p-Tau levels, a hallmark of a degenerative brain, since only aged animals had significant increases. MDMA evoked brain oxidative stress in the hippocampus and striatum of aged, and in the hippocampus, frontal cortex, and striatum brain areas of adolescents according to protein carbonylation, but only decreased GSH levels in the hippocampus of aged animals. The brain maturational stage seems crucial for MDMA-evoked serotonergic neurotoxicity. Aged animals were more susceptible to MDMA-induced tissue damage in the heart and kidneys, and both ages had an increase in liver fibrotic tissue content. In conclusion, age is a determinant factor for the toxic events promoted by "ecstasy". This work demonstrated special susceptibility of aged hippocampus to MDMA neurotoxicity, as well as impressive damage to the heart and kidney tissue following "ecstasy".


Asunto(s)
Envejecimiento/efectos de los fármacos , Encéfalo/efectos de los fármacos , Fiebre/inducido químicamente , N-Metil-3,4-metilenodioxianfetamina/toxicidad , Síndromes de Neurotoxicidad/etiología , Envejecimiento/metabolismo , Animales , Encéfalo/metabolismo , Dopamina , Fiebre/metabolismo , Corazón/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Síndromes de Neurotoxicidad/metabolismo , Ratas Wistar , Serotonina
10.
Skin Res Technol ; 24(2): 235-241, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29057515

RESUMEN

BACKGROUND/PURPOSE: During the injection of a fluid in a tissue model, the fluid might be affected by the needle tip configuration and the number of channels. Thus, the objective of the present work is to observe the influence of different needle tips and number of channels on the spread of a fluid. METHODS: Fluid distribution data were obtained after injecting 0.3 mL of fluid into a foamed polymer model with a velocity of 2 mm/s. The spread area and the depth were determined for 3 different types of hypodermic needles: Single channel needles with bevel tip and blunt tip and a needle with conical tip and 3 internal channels. RESULTS: The bevel tip provides a higher spread in the direction where the bevel points and reaches larger depths than the other two needles. The spread for the blunt tip and the polymer needle is equally distributed on both sides of the needle. The largest horizontal area around the tip is achieved by the 3-channel needle. CONCLUSION: The tip configuration and number of channels have an influence on the distribution of fluid. The bevelled needle directs the fluid and reaches larger depths compared with the 3-channel needle that gets more horizontal spread.


Asunto(s)
Agujas/normas , Administración Cutánea , Animales , Diseño de Equipo , Gelatina/administración & dosificación , Humanos , Inyecciones , Modelos Anatómicos , Polímeros , Piel Artificial , Acero , Porcinos , Viscosidad , Agua/administración & dosificación
11.
Int Braz J Urol ; 43(6): 1195, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28379670

RESUMEN

A 41-year-old male presented at Emergency Department (ED) with right flank pain associated with hematuria for 3 days. Patient had a previous history of nephrolithiasis. The physical examination and blood tests were normal. Urine analyses showed haematuria > 1.000.000/µL. After clinical evaluation, a computer tomography (CT) showed right ureteral dilata¬tion caused by a 5 mm proximal stone and a distal intraluminal mass of 8 cm in length. In this setting, an ureteroscopic biopsy was performed and revealed a large polypoid lesion histologically suggestive of fibroepithelial polyp. Due to technical difficulties (intraluminal mass length and technical issue for the passage of guidewire) and after discussing all available minimally invasive options, we opted for a laparoscopic approach. Instead of ureterectomy of the affected segment of the ureter, as classically performed, we proceeded with an ureterotomy, blunt dissection of the tumor and ureterolithotomy, with complete removal of the mass. This approach did not require ureteral anastomosis and the ureteral dilatation facilitated its primary closure. No complications occurred, even after 3 years of follow-up.


Asunto(s)
Neoplasias Fibroepiteliales/cirugía , Pólipos/cirugía , Neoplasias Ureterales/cirugía , Adulto , Humanos , Masculino , Neoplasias Fibroepiteliales/diagnóstico por imagen , Pólipos/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Neoplasias Ureterales/diagnóstico por imagen , Ureteroscopía/métodos
12.
Int J Dent Hyg ; 15(2): 135-141, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-26799625

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the impact of distinct phases of a non-surgical periodontal treatment protocol on oral health-related quality of life (OHRQoL). METHODS: Fifty-five participants (51.4 ± 9.4 years), diagnosed with both gingivitis and moderate-to-severe periodontitis, were included. Periodontal and OHRQoL (OHIP-14) data were collected before (Day 0) and after the supragingival (Day 30) and subgingival (Day 90) treatments. A linear mixed model was used. OHIP-14 scores, effect size, and ceiling and floor effects were calculated. RESULTS: The total OHIP-14 score was significantly higher at Day 0 (17.3 ± 10.5) compared to Day 30 (9.7 ± 8.3) and Day 90 (9.5 ± 7.4). Scores of all domains decreased significantly after the supragingival treatment. This response was maintained after the subgingival therapy, except in the physical pain and physical disability domains. Clinical variables were not associated with the change in OHIP scores. The effect size was 0.72 at Day 30 and 0.74 at Day 90. No ceiling and floor effect were observed. CONCLUSIONS: Perceptions on OHRQoL improved along periodontal therapy, particularly after the supragingival treatment, suggesting that this intervention might be considered important to reduce the negative impacts in oral health-related quality of life.


Asunto(s)
Raspado Dental , Gingivitis/terapia , Salud Bucal , Índice Periodontal , Periodontitis/terapia , Calidad de Vida , Adulto , Brasil , Femenino , Gingivitis/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Periodontitis/diagnóstico
13.
Physiol Genomics ; 48(11): 810-815, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27614204

RESUMEN

Recent genetic studies have revealed an association between polymorphisms at the ADAMTS7 gene locus and coronary artery disease (CAD) risk. Functional studies have shown that a CAD-associated polymorphism (rs3825807) affects ADAMTS7 maturation and vascular smooth muscular cell (VSMC) migration. Here, we tested whether ADAMTS7 (A/G) SNP is associated with cardiovascular (CV) survival in patients with established CAD. A cohort of 1,128 patients with angiographic proven CAD, who were followed up prospectively for a mean follow-up period of 63 (range 6-182) mo, were genotyped for rs3825807 A/G. Survival statistics (Cox regression) compared heterozygous (AG) and wild-type (AA) with the reference homozygous GG. Kaplan-Meier (K-M) survival curves were performed according to ADAMTS7 genotypes for CV mortality. Results showed that 47.3% of patients were heterozygous (AG), 36.5% were homozygous for the wild-type allele (AA) and only 16.2% were homozygous for the GG genotype. During the follow-up period, 109 (9.7%) patients died, 77 (6.8%) of CV causes. Survival analysis showed that AA genotype was an independent risk factor for CV mortality compared with reference genotype GG (HR = 2.7, P = 0.025). At the end of follow-up, the estimated survival probability (K-M) was 89.8% for GG genotype, 82.2% for AG and 72.3% for AA genotype (P = 0.039). Carriage of the mutant G allele of the ADAMTS7 gene was associated with improved CV survival in patients with documented CAD. The native overfunctional ADAMTS7 allele (A) may accelerate VSMC migration and lead to neointimal thickening, atherosclerosis progression and acute plaque events. ADAMTS7 gene should be further explored in CAD for risk prediction, mechanistic and therapeutic goals.


Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Proteína ADAMTS7/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
15.
J Anim Physiol Anim Nutr (Berl) ; 100(6): 1090-1096, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26857346

RESUMEN

In this study, we evaluated the requirements of calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na) and potassium (K) for sheep hair growth. Experimental diets contained different levels of metabolizable energy [ME; 0.96, 1.28, 1.72, 2.18 and 2.62 Mcal/kg of dry matter, (DM), corresponding to 4.23, 5.64, 7.58, 9.61 and 11.55 MJ/kg DM]. The lambs' hair (n = 48) at 2 months of age presented an average body weight (BW) of 12.05 ± 1.81 kg. At the beginning of the experiment, eight animals were slaughtered as a reference group to estimate the initial empty body weight and body composition. Net mineral requirements (g/day) ranged from 0.73 to 0.71 g of Ca, 0.51 to 0.49 g of P, 0.026 to 0.026 g of Mg, 0.16 to 0.19 g of Na and 0.15 to 0.13 g of K for animals with a BW ranging from 15 to 30 kg and a daily gain of 100 g. The results of this study indicate that the net macromineral requirements for weight gain in Morada Nova lambs are different from the values commonly recommended by the Agricultural and Food Research Council.


Asunto(s)
Calcio/metabolismo , Magnesio/metabolismo , Necesidades Nutricionales , Fósforo/metabolismo , Ovinos , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Peso Corporal , Calcio/administración & dosificación , Dieta/veterinaria , Magnesio/administración & dosificación , Fósforo/administración & dosificación , Clima Tropical
16.
Genet Mol Res ; 14(4): 15242-8, 2015 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-26634487

RESUMEN

Cratylia argentea (Desv.) Kuntze (Fabaceae) is a drought-tolerant, perennial legume found primarily in Brazil, Bolivia, and Peru. The shrub is well adapted to acid soils and exhibits high productivity and nutritional value, characteristics that would favor its use as a dry season animal forage supplement in semiarid regions. In plant improvement programs, the production of elite hybrids with superior traits is generally achieved by crossing parents that exhibit the highest level of genetic divergence. Therefore, the aim of the present study was to assess genetic diversity among 13 accessions of C. argentea from the same population maintained in the active germplasm bank of Embrapa Meio-Norte using inter-simple sequence repeat (ISSR) markers. Genetic similarities between C. argentea accessions were estimated from Jaccard coefficients, and a dendrogram was constructed using the unweighted pair group method with arithmetic average (UPGMA). The set of 15 primers selected for ISSR analysis generated a total of 313 loci of which 79.23% were polymorphic. The mean number of bands per primer was 20.87, and the amplicons ranged from 280 to 3000 bp in size. Primers UBC834 and UBC827 generated the largest number of polymorphic loci and exhibited 90.91 and 100% polymorphism, respectively. The coefficients of genetic similarity among accessions varied between 0.49 and 0.73. UPGMA cluster analysis allowed the identification of four genotypic groups and demonstrated the existence of considerable variability within the collection. Potential progenitors were selected that would offer good possibilities of obtaining unusual and favorable combinations of genes in a plant breeding program.


Asunto(s)
Fabaceae/genética , Marcadores Genéticos/genética , Repeticiones de Microsatélite/genética , Brasil , Cruzamiento/métodos , Análisis por Conglomerados , ADN de Plantas/genética , Variación Genética/genética , Genotipo , Perú , Filogenia , Polimorfismo Genético/genética
17.
Phys Rev Lett ; 113(2): 025506, 2014 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-25062208

RESUMEN

Perfectly crystalline solids are excellent heat conductors. Prominent counterexamples are intermetallic clathrates, guest-host systems with a high potential for thermoelectric applications due to their ultralow thermal conductivities. Our combined experimental and theoretical investigation of the lattice dynamics of a particularly simple binary representative, Ba(8)Si(46), identifies the mechanism responsible for the reduction of lattice thermal conductivity intrinsic to the perfect crystal structure. Above a critical wave vector, the purely harmonic guest-host interaction leads to a drastic transfer of spectral weight to the guest atoms, corresponding to a localization of the propagative phonons.

18.
J Evol Biol ; 27(9): 1775-83, 2014 09.
Artículo en Inglés | MEDLINE | ID: mdl-24898362

RESUMEN

Hybrid male sterility is a common outcome of crosses between different species. Gene expression studies have found that a number of spermatogenesis genes are differentially expressed in sterile hybrid males, compared with parental species. Late-stage sperm development genes are particularly likely to be misexpressed, with fewer early-stage genes affected. Thus, a link has been posited between misexpression and sterility. A more recent alternative explanation for hybrid gene misexpression has been that it is independent of sterility and driven by divergent evolution of male-specific regulatory elements between species (faster male hypothesis). The faster male hypothesis predicts that misregulation of spermatogenesis genes should be independent of sterility and approximately the same in both hybrids, whereas sterility should only affect gene expression in sterile hybrids. To test the faster male hypothesis vs. the effect of sterility on gene misexpression, we analyse spermatogenesis gene expression in different species pairs of the Drosophila phylogeny, where hybrid male sterility occurs in only one direction of the interspecies cross (i.e. unidirectional sterility). We find significant differences among genes in misexpression with effects that are lineage-specific and caused by sterility or fast male regulatory divergence.


Asunto(s)
Drosophila/genética , Infertilidad Masculina/genética , Espermatogénesis/genética , Animales , Quimera , Femenino , Fertilidad , Regulación de la Expresión Génica , Masculino , Motilidad Espermática/genética
19.
Genet Mol Res ; 13(2): 4486-93, 2014 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-25036353

RESUMEN

Molecular markers are important for characterizing the genetic diversity of plants and can provide the basis for strategies to protect and conserve endangered populations. However, numerous molecular techniques are used, requiring an evaluation of fast and efficient methods to extract DNA. Since molecular studies of Caesalpinia ferrea are rare, it is important to develop and/or adapt a DNA extraction protocol that produces quality DNA samples to enable the design of strategies for the conservation of this threatened species. This study aimed to compare five methods for DNA extraction and to determine the most efficient protocol for C. ferrea. Sufficient genomic DNA was obtained from the leaves of C. ferrea using all the tested protocols to perform techniques involving molecular markers. Two protocols based on the detergent cetyl trimethyl ammonium bromide, as well as a commercial kit, yielded high concentrations of pure DNA. However, when polymerase chain reaction amplifications were performed, DNA was only successfully amplified from extractions performed with the commercial kit, which produced sufficient genomic DNA of good quality from the leaves of C. ferrea to perform techniques involving molecular markers.


Asunto(s)
Caesalpinia/genética , ADN de Plantas/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Bromuros/química , Detergentes/química , Hojas de la Planta/genética , Compuestos de Amonio Cuaternario/química , Juego de Reactivos para Diagnóstico
20.
Vet J ; 306: 106178, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38906413

RESUMEN

Thoracolumbar hydrated nucleus pulposus extrusion (TL-HNPE) is an increasingly recognised pathology with a substantial lack of literature describing its features. The aim of this retrospective case-control study was to analyse the clinical and magnetic resonance imaging (MRI) features of dogs with TL-HNPE compared to dogs affected with thoracolumbar intervertebral disc extrusion (TL-IVDE). Data from dogs diagnosed with TL-HNPE and TL-IVDE via MRI at two referral hospitals, were retrospectively collected and compared in terms of clinical signs and MRI features. Cases diagnosed with TL-IVDE were deemed controls. The MRI features of the affected IVD space, herniated IVD material, affected overlying spinal cord and local epaxial musculature were evaluated for each group. Fifty-one cases with TL-HNPE and 105 randomly selected cases of TL-IVDE were included. Several signalment and neurological signs were identified as statistically distinct between groups in univariate analysis. Multivariate analysis identified that dogs affected with TL-HNPE were typically older, less likely to be chondrodystrophic (62.2 % vs. 91 %), more frequently experiencing a peracute onset (90.2 % vs. 61.9 %) often attributed to a suspected trauma linked with exercise (37.3 % vs. 10.5 %), being less frequently progressive (41.2 % vs. 86.5 %) and with herniated disc material less frequently lateralised (72.6 % vs. 89.5 %) than cases with TL-IVDE. MRI-identifiable intervertebral disc degeneration was found in every TL-IVDE case but only in 60 % of TL-HNPE cases. TL-HNPEs were associated to significantly less spinal cord compression and less hyperalgesia than TL-IVDE.


Asunto(s)
Enfermedades de los Perros , Desplazamiento del Disco Intervertebral , Imagen por Resonancia Magnética , Núcleo Pulposo , Animales , Perros , Enfermedades de los Perros/diagnóstico por imagen , Imagen por Resonancia Magnética/veterinaria , Desplazamiento del Disco Intervertebral/veterinaria , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Estudios Retrospectivos , Núcleo Pulposo/diagnóstico por imagen , Núcleo Pulposo/patología , Masculino , Femenino , Estudios de Casos y Controles , Degeneración del Disco Intervertebral/veterinaria , Degeneración del Disco Intervertebral/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen
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