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This study aims to identify dental materials and their effectiveness in preventing caries in patients after chemotherapy and radiotherapy for the head and neck. The electronic search was performed in PubMed, Science Direct, Embase and Scopus. All 653 articles found passed through a double-blinded screening process. The exclusion of articles by reading titles and abstracts selected 16 articles for full reading, of which 4 were included into the study. A risk of bias analysis for non-randomized and randomized articles was performed using respectively the ROBINS I and ROB II tools. The data extraction suggested that the casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), in association with fluorine, is able to form harder surfaces compared to the control group, the intraoral fluoride-releasing system (IFRS) effectiveness is similar to the fluorine in gel and a mouthwash composed of natural enzymes (Oral7) did not demonstrate effectiveness in the prevention dental caries. New randomized controlled clinical trials are necessary to evaluate the effectiveness of prevention when applying dental materials in patients after treatment of head and neck cancer.

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The major rDNA genes are composed of tandem repeats and are part of the nucleolus organizing regions (NORs). They are highly conserved and therefore useful in understanding the evolutionary patterns of chromosomal locations. The evolutionary dynamics of the karyotype may affect the organization of rDNA genes within chromosomes. In this study, we physically mapped 18S rDNA genes in 13 Neotropical ant species from four subfamilies using fluorescence in situ hybridization. Furthermore, a survey of published rDNA cytogenetic data for 50 additional species was performed, which allowed us to detect the evolutionary patterns of these genes in ant chromosomes. Species from the Neotropical, Palearctic, and Australian regions, comprising a total of 63 species from 19 genera within six subfamilies, were analysed. Most of the species (48 out of 63) had rDNA genes restricted to a single chromosome pair in their intrachromosomal regions. The position of rDNA genes within the chromosomes appears to hinder their dispersal throughout the genome, as translocations and ectopic recombination are uncommon in intrachromosomal regions because they can generate meiotic abnormalities. Therefore, rDNA genes restricted to a single chromosome pair seem to be a plesiomorphic feature in ants, while multiple rDNA sites, observed in distinct subfamilies, may have independent origins in different genera.

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RESUMEN: Aunque la radiografía panorámica no es una prueba de diagnóstico inicial para detectar la aterosclerosis carotídea, no podemos ignorar su valor al ver estas lesiones como hallazgos incidentales que pueden ser grandes aliados en el diagnóstico temprano y la prevención de eventos vasculares graves. El objetivo de este estudio fue evaluar la prevalencia de calcificaciones en la bifurcación de la arteria carótida en las radiografías panorámicas de rutina como principio diagnóstico, así como su relación con los factores de riesgo cardiovascular en individuos brasileños. Se analizaron 449 exámenes de radiografía panorámica de la base de datos del Departamento de Radiología de la Facultad de Odontología de Piracicaba, UNICAMP, São Paulo, Brasil. Después de obtener mediciones de la presión arterial e información sobre el tabaquismo y las enfermedades sistémicas, fue buscado en la radiografía panorámica la presencia o ausencia de la masa radiopaca en las regiones de las vértebras cervicales C3-C4. En el caso de una imagen sugestiva de ateroma, se realizó una radiografía anteroposterior para confirmar el diagnóstico. Aplicamos la prueba estadística de Chi-cuadrado con distribución normal y muestras independientes y aleatorias con un intervalo de confianza del 95 %. La confirmación de calcificaciones carotideas se produjo en el 8,5 % de la población de estudio (38 casos). No encontramos ninguna relación entre la presencia de calcificaciones con el tabaquismo, con el sexo o con datos previos de antecedentes familiares. Sin embargo 49,1 % de los casos estaban por encima de sesenta años y tenía asociación significativa con la hipertensión (P = 0,006). El mayor riesgo se presenta en pacientes ancianos hipertensos y, por lo tanto, hacemos hincapié en la importancia de una observación minuciosa de las radiografías panorámicas en la búsqueda de cualquier alteración de la anatomía normal y si es así, proceder con la derivación lo antes posible para un diagnóstico concluyente por parte de un especialista, pudiendo así ayudar en la prevención de episodios vasculares graves.

SUMMARY: Although panoramic radiography is not an initial diagnostic test for detecting carotid atherosclerosis, we cannot ignore its value in viewing these lesions as incidental findings that can be great allies in early diagnosis and prevention of serious vascular events. The aim was to evaluate the prevalence of calcifications in the bifurcation of the carotid artery on routine panoramic radiographs as a diagnostic principle, as well as its relationship with cardiovascular risk factors in Brazilians. We analyzed 449 panoramic radiography exams from the database of the Department of Radiology of the Faculty of Dentistry of Piracicaba, UNICAMP, São Paulo, Brazil. After obtaining blood pressure measurements and information on smoking and systemic diseases, the researcher observed on the panoramic radiograph, the presence or absence of the radiopaque mass in the regions of the cervical vertebrae C3-C4. In the case of a suggestive image of atheroma, an anteroposterior radiography was performed to confirm the diagnosis. The Chi-square test of normal distribution for independent and random samples with a 95 % confidence interval was applied to the data. Confirmation of carotid calcifications occurred in 8.5 % of the study population (38 cases). We did not find any relationship between the presence of calcifications with smoking, sex or previous family history. However, 49.1 % of cases occurred above sixty years old and there was a significant relationship with hypertension (P = 0.006). The greatest risk was presented in elderly and hypertensive patients, so we highlight the importance of a thorough observation by the dentist of panoramic radiographs to detect any alteration of the normal anatomy and in the positive case, proceed with the referral as soon as possible for a conclusive diagnosis by a specialist, being able to thus assist in the prevention of severe vascular episodes.

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Hydrophobic oil droplets, particles, and air bubbles can be dispersed in water as kinetically stabilized dispersions. It has been established since the 19th century that such objects harbor a negative electrostatic potential roughly twice larger than the thermal energy. The source of this charge continues to be one of the core observations in relation to hydrophobicity, and its molecular explanation is still debated. What is clear though is that the stabilizing interaction in these systems is understood in terms of electrostatic repulsion via Derjaguin, Landau, Verwey, and Overbeek theory. Recent work [A. P. Carpenter et al., Proc. Natl. Acad. Sci. U. S. A. 116, 9214 (2019)] has added another element into the discussion, reporting the creation of bare near-zero charged droplets of oil in neat water that are stable for several days. Key to the creation of the droplets is a rigorous glassware cleaning procedure. Here, we investigate these conclusions and show that the cleaning procedure of glassware has no influence on the electrophoretic mobility of the droplets and that oil droplets with near-zero charge are unstable. We provide an alternative possible explanation for the observations involving glass surface chemistry.

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Two experiments were designed to evaluate the impact of puberty status and the administration of melengestrol acetate (MGA) before onset of the breeding period on ovulatory responses (Exp. 1) and conception rate after AI performed on estrus detection during 10 d and the pregnancy rate through 80 d of breeding period (Exp. 2) of pasture-grazed beef heifers. In Exp. 1, heifers (15 pubertal and 15 prepubertal) received 0.5 mg per heifer/d -1 of MGA over 14 d. No differences in the ovulatory responses were found 10 d after the MGA administration (pubertal = 46.7% vs. prepubertal P = 53.3%; P = 0.72). In Exp. 2, 368 heifers were randomly assigned to groups according to pubertal status and the MGA treatment. All heifers were inseminated on estrus detection for up 10 d after MGA administration and following exposure to bulls between 20 and 80 d. The MGA-treated heifers exhibited a greater AI service rate than control heifers (72.1 vs. 41.6%;P < 0.01); however, heifers receiving MGA had lower conception results following AI (51.6 vs. 71.4%; P = 0.01). In addition, MGA-treated heifers were more likely to have a corpus luteum in the middle of the breeding period (95.3 vs. 87.5%;P < 0.01), although the Cox proportional hazard of pregnancy rate was similar (P = 0.29) at the end of the breeding period. At onset of the breeding period, pubertal heifers presented a greater pregnancy rate following AI (pubertal P = 42.2% vs. prepubertal P = 24.9%; P = 0.01). Therefore, pubertal heifers seem to have greater overall reproductive efficiency than prepubertal heifers, particularly at the beginning of the breeding period. Interestingly, administration of MGA before the onset of the breeding period increased AI service rate but did not alter the rate of pregnancy throughout the breeding period of pasture-grazed beef heifers.

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Many processes in chemistry and physics rely on the structure, growth or change of material buried in solids. The impenetrable surrounding medium often prohibits the study of such material in situ. Nonlinear light scattering can be used to observe the internal structure of a crystalline state embedded inside another solid state. Vibrational sum frequency scattering patterns of polymer microspheres, consisting of both amorphous and crystalline material, reveal the size of the buried microstructure and the optical components of the second-order susceptibility of the material. The vibrational spectra reveal the molecular structure.

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Five cases of eosinophilic meningoencephalitis presumed to be caused by the rat lungworm, Angiostrongylus cantonensis, are reported from localities in or near Havana, Cuba. The first typical case occurred in 1973. Lungworms identified as A. cantonensis were found in rats from the same localities. The clinical picture in the Cuban cases, as in cases from other countries, is that of a self-limiting disease without apparent sequelae.

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