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BACKGROUND: Dental implant materials play a pivotal role in the success of restorative dentistry. This study comprehensively compares the mechanical and esthetic properties of three commonly used dental implant materials: titanium, zirconia, and ceramic. OBJECTIVE: This study aimed to provide insights into the suitability of titanium, zirconia, and ceramic for various clinical applications within implant dentistry. METHODS: Ninety dental implants, 30 for each material, were selected based on their well-established usage in dental implantology. Mechanical properties, including tensile strength, modulus of elasticity, and fatigue resistance, were assessed using state-of-the-art testing machines. Esthetic properties, such as color stability and translucency, were scrutinized through immersion in staining solutions and spectrophotometer measurements. Fracture properties and biocompatibility were also evaluated. RESULTS: Mechanical testing revealed that titanium exhibited the highest tensile strength (810 ± 55 MPa), while zirconia demonstrated the highest modulus of elasticity (208 ± 8 GPa). Titanium also displayed the greatest fatigue resistance (1,010,000 ± 95,000 cycles), whereas zirconia had the highest hardness (1190 ± 45 Vickers hardness number (VHN)). Esthetically, zirconia showed superior color stability (ΔE: 1.7 ± 0.2), while ceramic exhibited the highest translucency (TP%: 15.3 ± 1.7). Zirconia presented the lowest surface roughness (0.28 ± 0.04 µm). CONCLUSION: This study provides insights into potential dental implant material performance, with zirconia emerging as a promising alternative. Future research should validate these findings in clinical settings, considering a broader array of variables and long-term outcomes.
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BACKGROUND: Physical activity (PA) plays an important role in optimizing health outcomes throughout pregnancy. In many low-income countries, including Nepal, data on the associations between PA and pregnancy outcomes are scarce, likely due to the lack of validated questionnaires for assessing PA in this population. Here we aimed to evaluate the reliability and validity of an adapted version of Global Physical Activity Questionnaire (GPAQ) among a sample of pregnant women in Nepal. METHODS: A cohort of pregnant women (N=101; age 25.9±4.1 years) was recruited from a tertiary, peri-urban hospital in Nepal. An adapted Nepali version of GPAQ was administered to gather information about sedentary behavior (SB) as well as moderate and vigorous PA across work/domestic tasks, travel (walking/bicycling), and recreational activities, and was administered twice and a month apart in both the 2nd and 3rd trimesters. Responses on GPAQ were used to determine SB (min/day) and total moderate to vigorous PA (MVPA; min/week) across all domains. GPAQ was validated against PA data collected by a triaxial accelerometer (Axivity AX3; UK) worn by a subset of the subjects (n=21) for seven consecutive days in the 2nd trimester. Intra-class correlation coefficients (ICC) and Spearman's rho were used to assess the reliability and validity of GPAQ. RESULTS: Almost all of the PA in the sample was attributed to moderate activity during work/domestic tasks or travel. On average, total MVPA was higher by 50 minutes/week in the 2nd trimester as compared to the 3rd trimester. Based on the World Health Organization (WHO) guidelines, almost all of the participants were classified as having a low or moderate level of PA. PA scores for all domains showed moderate to good reliability across both the 2nd and 3rd trimesters, with ICCs ranging from 0.45 (95%CI: (0.17, 0.64)) for travel PA at 2nd trimester to 0.69 (95%CI: (0.51, 0.80)) for travel PA at 3rd trimester. Reliability for total MVPA was higher in the 3rd trimester compared to 2nd trimester [ICCs 0.62 (0.40, 0.75) vs. 0.55 (0.32, 0.70)], whereas the opposite was true for SB [ICCs 0.48 (0.19, 0.67) vs. 0.64 (0.46, 0.76)]. There was moderate agreement between the GPAQ and accelerometer for total MVPA (rho = 0.42; p value <0.05) while the agreement between the two was poor for SB (rho= 0.28; p value >0.05). CONCLUSIONS: The modified GPAQ appears to be a reliable and valid tool for assessing moderate PA, but not SB, among pregnant women in Nepal.
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Coronavirus Disease-2019 tests require a Nasopharyngeal (NP) and/or Oropharyngeal (OP) specimen from the upper airway, from which virus RNA is extracted and detected through quantitative reverse transcription-Polymerase Chain Reaction (qRT-PCR). The viability of the virus is maintained after collection by storing the NP/OP swabs in Viral Transport Media (VTM). We evaluated the performance of four transport media: locally manufactured ("REVITAL") Viral Transport Media (RVTM), Standard Universal Transport Media (SUTM), PBS and 0.9% (w/v) NaCl (normal saline). We used laboratory cultured virus to evaluate: i) viral recovery and maintaining integrity at different time periods and temperatures; ii) stability in yielding detectable RNA consistently for all time points and conditions; and iii) their overall accuracy. Four vials of SARS-CoV-2 cultured virus (2 high and 2 low concentration samples) and 1 negative control sample were prepared for each media type (SUTM, RVTM, PBS and normal saline) and stored at the following temperatures, -80°C, 4°C, 25°C and 37°C for 7 days. Viral RNA extractions and qRT-PCR were performed at 1, 2, 3, 4 and 7 days after inoculation with the cultured virus to assess virus stability and viral recovery. Ct values fell over time at 25°C and 37°C, but normal saline, PBS, RVTM and SUTM all showed comparable performance in maintaining virus integrity and stability allowing for the detection of SARS-CoV-2 RNA. Overall, this study demonstrated that normal saline, PBS and the locally manufactured VTM can be used for COVID-19 sample collection and testing, thus expanding the range of SARS-CoV-2 viral collection media.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Solución Salina , ARN Viral/genética , ARN Viral/análisis , Manejo de Especímenes , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Prueba de COVID-19RESUMEN
OBJECTIVES: Here we examined the reproducibility and validity of a dietary screener which was translated and adapted to assess diet quality among pregnant Nepalese women. METHODS: A pilot cohort of singleton pregnant women (N = 101; age 25.9 ± 4.1 years) was recruited from a tertiary, periurban hospital in Nepal. An adapted Nepali version of the PrimeScreen questionnaire, a brief 21-item dietary screener that assesses weekly consumption of 12 healthy and 9 unhealthy food groups, was administered twice, and a month apart, in both the 2nd and 3rd trimesters. Up to four inconsecutive 24-h dietary recalls (24-HDRs) were completed each trimester and utilized as the reference method for validation. For each trimester, data from multiple 24-HDRs were averaged across days, and items were grouped to match the classification and three weekly consumption categories (0-1, 2-3, or 4 + servings/week) of the 21 food groups represented on the PrimeScreen. RESULTS: Gwet's agreement coefficients (AC1) were used to evaluate the reproducibility and validity of the adapted PrimeScreen against the 24-HDRs in both the 2nd and 3rd trimester. AC1 indicated good to excellent (≥ 0.6) reproducibility for the majority (85%) of food groups across trimesters. There was moderate to excellent validity (AC1 ≥ 0.4) for all food groups except for fruits and vegetables in the 2nd trimester, and green leafy vegetables and eggs in both the 2nd and 3rd trimesters. CONCLUSIONS: The modified PrimeScreen questionnaire appears to be a reasonably valid and reliable instrument for assessing the dietary intake of most food groups among pregnant women in Nepal.
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Dieta , Mujeres Embarazadas , Femenino , Humanos , Embarazo , Adulto Joven , Adulto , Nepal , Reproducibilidad de los Resultados , Verduras , Encuestas y Cuestionarios , Encuestas sobre DietasRESUMEN
The Axin family of scaffolding proteins regulates a wide array of developmental and post-developmental processes in eukaryotes. Studies in the nematode Caenorhabditis elegans have shown that the Axin homolog PRY-1 plays essential roles in multiple tissues. To understand the genetic network of pry-1, we focused on a set of genes that are differentially expressed in the pry-1-mutant transcriptome and are linked to reproductive structure development. Knocking down eight of the genes (spp-1, clsp-1, ard-1, rpn-7, cpz-1, his-7, cdk-1, and rnr-1) via RNA interference efficiently suppressed the multivulva phenotype of pry-1 mutants. In all cases, the ectopic induction of P3.p vulval precursor cell was also inhibited. The suppressor genes are members of known gene families in eukaryotes and perform essential functions. Our genetic interaction experiments revealed that in addition to their role in vulval development, these genes participate in one or more pry-1-mediated biological events. Whereas four of them (cpz-1, his-7, cdk-1, and rnr-1) function in both stress response and aging, two (spp-1 and ard-1) are specific to stress response. Altogether, these findings demonstrate the important role of pry-1 suppressors in regulating developmental and post-developmental processes in C. elegans. Given that the genes described in this study are conserved, future investigations of their interactions with Axin and their functional specificity promises to uncover the genetic network of Axin in metazoans.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Envejecimiento , Animales , Proteína Axina/genética , Proteína Axina/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Femenino , Redes Reguladoras de Genes , Vulva/metabolismoRESUMEN
Diabetic retinopathy (DR), one of the leading causes of blindness, is mainly diagnosed based on the vascular pathology of the disease. Current treatment options largely focus on this aspect with mostly insufficient therapeutic long-term efficacy. Mounting evidence implicates mitochondrial dysfunction and oxidative stress in the central etiology of DR. Consequently, drug candidates that aim at normalizing mitochondrial function could be an attractive therapeutic approach. This study compared the mitoprotective compounds, idebenone and elamipretide, side-by-side against two novel short-chain quinones (SCQs) in a rat model of DR. The model effectively mimicked type 2 diabetes over 21 weeks. During this period, visual acuity was monitored by measuring optokinetic response (OKR). Vision loss occurred 5-8 weeks after the onset of hyperglycemia. After 10 weeks of hyperglycemia, visual function was reduced by 65%. From this point, the right eyes of the animals were topically treated once daily with the test compounds. The left, untreated eye served as an internal control. Only three weeks of topical treatment significantly restored vision from 35% to 58-80%, while visual acuity of the non-treated eyes continued to deteriorate. Interestingly, the two novel SCQs restored visual acuity better than idebenone or elamipretide. This was also reflected by protection of retinal pathology against oxidative damage, retinal ganglion cell loss, reactive gliosis, vascular leakage, and retinal thinning. Overall, mitoprotective and, in particular, SCQ-based compounds have the potential to be developed into effective and fast-acting drug candidates against DR.
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Antioxidantes/uso terapéutico , Retinopatía Diabética/tratamiento farmacológico , Ubiquinona/análogos & derivados , Animales , Antioxidantes/farmacología , Masculino , Mitocondrias/efectos de los fármacos , Oligopéptidos/farmacología , Oligopéptidos/uso terapéutico , Ratas , Ratas Long-Evans , Ubiquinona/farmacología , Ubiquinona/uso terapéutico , Visión OcularRESUMEN
Congenital granular cell lesion, or congenital epulis, is a rare lesion of the newborn. The sight of a newborn infant with congenital epulis can be startling for both parents and healthcare professionals. The lesion appears most commonly in the maxillary alveolar ridge, with predominance in females. The etiology and histogenesis of the lesion remain obscure. This lesion can pose a risk of airway obstruction or can interfere with feeding. The report presented here describes a case of congenital granular cell lesion in the left maxillary region. The lesion was causing a feeding problem and, hence, was excised under local anesthesia.
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Neoplasias Gingivales/congénito , Neoplasias Maxilares/congénito , Biopsia , Diagnóstico Diferencial , Femenino , Humanos , Recién NacidoRESUMEN
Functional, esthetic and endodontic restoration of a pulpally involved permanent incisor with root dilaceration often presents a daunting clinical challenge. The outcome of conventional treatment modalities like surgical removal of the tooth followed by orthodontic closure of the space is time consuming and esthetically compromising. Even the prosthetic and implantalogical rehabilitation after extraction is not possible until the patient reaches certain age; while the compliance is a problem with the use of removable partial denture in young children. Autoalloplastic anterior tooth transplantation can lead to physical and psychological trauma in a young individual. Thus endo-esthetic management of such teeth helps in maintaining both morphology and esthetics in a growing child until the permanent long lasting prosthetic solution is sought after the complete development of the dentition and jaws. This treatment option for a pulpally involved permanent incisor with root dilaceration involves completing the endodontic treatment in a partially calcified and aberrantly located root canal followed by the use of light transmitting fiber post and core build up using composite resin.