Valorization of rice biomass by a green approach to release phenolic compounds and their antioxidant activities.

In the present context, we have assessed the green approach for the extraction of phenolics from agro-residues of rice viz., rice bran, and rice straw using water as an extracting solvent. The extraction was optimized with respect to time, temperature, pH, and solid (agro-residues) to liquid (water) ratio. The hydrolysates obtained were determined for phenolics and their antioxidant activities. The maximum total phenolic content (61.32 mg/100 g GAE), flavonoid content (13.19 mg/100 g QE), and tannin content (58.33 mg/100 g TAE) were obtained for rice bran followed by rice straw at pH 5, 1:20 (solid: liquid) for 10 min of extraction. Also, higher antioxidant properties (78.03% for DPPH, 86.45% for ABTS, and 0.85 absorbance at 700 nm for FRAP) were observed for the extracts of rice bran. Caffeic acid, gallic acid, p-coumaric acid, syringic acid, ferulic acid, 2,5-dihydroxy benzoic acid, kaemferol, quercetin, and epicatechin were analyzed by HPLC in both the rice biomass used. This study significantly converts rice biomass to antioxidative phenolic compounds under simple extraction conditions favoring the waste management process and also adding value to the waste biomass.

Strategies of Bioceramics, Bioactive Glasses in Endodontics: Future Perspectives of Restorative Dentistry.

Prevalently, there is a primary strategy to cure caries using restorative materials notably bioceramics. Existing synthetic materials stimulate natural tooth structure with acceptable interfacial bonding and esthetic and biomechanical qualities with better durability. Several bioceramics have been introduced and investigated for their potentialities as restorative materials. Biomineralization of tooth initiates repair and regeneration of natural dental tissue and reinstating the integrity of periodontium. In the evolution of bioceramics in the aspects of different essential composition for dental application, recent technology and modern strategies revolutionize the restorative dentistry. Bioglass is one among the important bioceramics as a restorative material, and by regulating the properties of the material, it is possible to construct improved formulation towards restoration. This article reviews the current revolution of endodontics, existing restorative materials, and technologies to be achieve for engineering materials with the better design.

Effect of disinfectants on the tear strength of addition silicone impression material - An in vitro study.

Addition silicone is a newer type of silicone impression material which has high dimensional stability, accuracy, and flexibility. They are mostly used for fixed restorations such as crowns and bridges. They have high tear strength; however, this strength may be altered upon disinfection. Disinfection of addition silicone prior use is important to reduce the microbial load. The aim of this study is to check whether there is any change in tear strength of addition silicone on disinfection with two commercially available disinfectants. Zhermack Elite HD + Putty material was tested in this study. Base and catalyst material was mixed and the material was cut into strips of dimension 70 mm × 10 mm × 2 mm. Five strips were immersed in sterillium and five strips were immersed in glutaraldehyde solution. These strips were then tested for their tear strength using Instron E3000 Universal Testing Machine. The values obtained were recorded in SPSS software version 22 (IBM SPSS Statistics for Windows, Version 23.0. Armonk, NY: IBM Corp.) for analysis and the P was obtained. The mean tear strength of Group 1, addition silicone immersed in sterillium disinfecting solution was found to be 7.148 ± 2.654 kN/m. The mean tear strength of Group 2, addition silicone immersed in glutaraldehyde disinfectant solution was found to be 7.326 ± 4.062 kN/m. An unpaired Student's t-test was done and P was found to be 0.235. The tear strength values between the groups was statistically not significant. Hence the tear strength of addition silicone was found to be greater in the glutaraldehyde disinfectant solution group.

Estimation of wettability of topical fluoride gel on anterior and posterior teeth: An in vitro study.

The surface area determination has a vital role in measuring the properties of liquid and solid substances. Fluoride is a potent remineralizing agent of the teeth. The surface area is measured using a goniometer. The main aim of this study is to estimate the wettability of topical fluoride gel on the anterior and posterior teeth surfaces. Topical acidulated phosphate fluoride (APF) gel was taken in small quantities. Anterior and posterior teeth were collected, and their superficial unaltered enamel sections were used as the surface where the contact angle (CA) is determined. The surface wettability is determined using Ossila goniometer to measure CA. Each stage was mounted on a mechanical stage of the goniometer. A calibrated microsyringe was used to dispense drops of the APF gel over the surface of the specimen Group A (anterior tooth cut section) and Group B (posterior tooth cut section). This procedure is repeated for all specimen samples. The mean of CAs of the anterior teeth (88.41°) was greater when compared with the mean of posterior teeth (80.36°) CA. P value found using the paired t-test of SPSS software is found to be 0.271 (>0.05), hence statistically not significant. The greater the CA, the lower is the degree of wettability on the teeth surfaces. The mean CA of the topical fluoride APF gel on the anterior tooth surface is greater when compared to the posterior tooth surface. This signifies that greater wettability is seen on posterior tooth surfaces.

Surface roughness changes of two composite resin restorative materials after thermocycling.

Composite is usually a mixture of two phases. The composites used in dentistry have high durability. The individual properties of each phase are important to increase the mechanical property of the composite. This study aimed to determine the surface roughness changes of two composite resin restorative materials after thermocycling. Two of the commercially available composites were chosen (RestoFill and SwissTEC). The composite disks of dimension 10 mm diameter and 3 mm height were prepared using silicone molds, and every increment was light cured for 30 s. A stylus profilometer was used to assess the surface roughness prethermocycling, and then, the disks were subjected to an integrated thermocycler (T.S-4.4) for 1000 cycles. The postsurface roughness was obtained after the thermocycling process using the same stylus profilometer. The surface parameter values before and after thermocycling of the SwissTEC sample is less than that of RestoFill. There was a significant difference between the Rz and Rq values of the two different commercially available composite materials. Thus, the present study concludes that thermocycling influenced the surface roughness of composite resin and increased the surface roughness of both the RestoFill and SwissTEC composites.

Evaluation of flexural strength of glass ionomer cement after immersion in fruit juices.

Glass ionomer cement (GIC) is a material used for restoration in dentistry. The stress in a material right before it yields in a flexure test is referred to as flexural strength. The aim of this study was to evaluate the flexural strength of two different glass ionomers after immersion in fruit juices. Five samples of D-Tech and Shofu GIC were prepared from each for the in vitro study. The eight samples were subjected to a flexural strength process and two were left as control which was followed by the determination of maximum force and displacement, then the collected data were used to determine flexural strength and analyzed using SPSS software (IBM SPSS Statistics for Windows, Version 22.0. Armonk, NY: IBM Corp). The mean value of flexural strength of the D-Tech GIC immersed in fruit juices is 4.4375 and the mean value of Shofu GIC immersed in fruit juices was 8.4975. Paired t-test was done between the two groups and the P value was 0.00, which is considered highly statistically significant. From this study, it is evident that the GIC brand Shofu has higher flexural strength compared to D-Tech. Flexural strength was decreased for both the GIC groups when immersed in grape juice.

Effect of carbonated beverages on flexural strength property of restorative glass ionomer cement.

Glass ionomer cement (GIC) releases fluorides and has good biocompatibility, carbonated drinks, sometimes known as fizzy drinks, are carbonated liquids that contain dissolved carbon dioxide, sweeteners, and natural or artificial flavoring. The aim of our study is to determine the flexural strength of GIC after immersing in carbonated beverages. Twelve samples of GIC filling material were used among which six samples prepared were from the Dtech brand and six were prepared from the Shofu brand for the in vitro study. Bar-shaped specimens were prepared from each group with the dimension of 2 mm × 2 mm × 25 mm. They were immersed in Sprite, fizz drinks, and in distilled water as a control group. The immersion period was 7 days. Then, the determination of maximum force and displacement was done using INSTRON E3000 (ElectroPuls) universal testing machine, then the collected data were used to determine flexural strength. The mean flexural strength of Dtech GIC was 24.84 ± 6.523 Mpa. The mean flexural strength of Dtech GIC was 18.57 ± 11.60 Mpa. The independent sample t-test showed that P = 0.247 (>0.05) which was statistically not significant. The flexural strength of GIC material decreased after being immersed in Sprite and fizz drinks.

Evaluation of tensile strength of surgical absorbable and nonabsorbable suture materials after immersion in different fruit juices: An in vitro study.

Surgical sutures are the most well-known surgical biomaterial device for ligating blood vessels. The primary goal of wound closure is to align wound margins to provide a closed and stable environment. Sutures with lesser tensile strength are susceptible to break throughout the healing process due to edema. To evaluate the tensile strength of absorbable and nonabsorbable suture materials after immersion in fruit juices. In this in vitro study, eight samples of commercially available sutures such as black silk and vicryl were divided into two groups: sample -1 were immersed in grape juice and sample -2 were immersed in lemon juice for 1 week. Universal testing machine INSTRON E300 UTM was used to test the tensile strength of various suture materials. The data are statistically analyzed using an independent t-test. The P < 0.05 was considered to be statistically significant. The mean of vicryl suture after immersion in grape and lemon juice was found to be 34.445 and 43.39; the mean value of black silk after immersion in grape and lemon juice was found to be 36.95 and 33.1. The tensile strength of black silk was slightly lower than the vicryl. Independent sample t-test showed that P = 0.561 (>0.05) which is statistically insignificant. Vicryl suture tested to have the highest tensile strength along with excellent knot holding capacity than black silk suture after immersion in fruit juices.

Effect of carbonated beverages on flexural strength of composite restorative material.

Carbonated beverages have side effects on oral health and general health. Flexural strength is a prime mechanical property of restorative material. The aim of this study is to know the effect of carbonated beverages on the flexural strength of composite restorative material. Two types of composites (Ivoclar and Restofill) were used as samples for comparative evaluation of flexural strength. The sample size is 10 where 5 of each type of composites are included. The obtained samples were immersed in carbonated beverages. One sample of each type was used as a control. After 24 h, the flexural strength of all the 10 samples was evaluated using the formula (3FL/2bd2), and the values were tabulated. Average values and graphs were done using SPSS software. The results showed the changes in flexural strength of both Ivoclar and Restofill materials when immersed in carbonated beverages. The mean value of all the samples was taken, and the standard deviation was calculated. After immersion in carbonated liquids, the mean value of Ivoclar and Restofill samples is 58.9 and 35.01, respectively. P = 0.718 (>0.05), which was not statistically significant. After immersion in Coke, the Restofill group exhibits more flexural strength than the Ivoclar group composite; however, the strength reduces when immersed in Sprite as compared to the Ivoclar group composite.

Effect of brushing simulation on the surface roughness of soft-tissue liners: An in vitro study.

Soft denture liners evenly distribute functional loads over denture-bearing tissues. The liners aid in more evenly distributing the pressures of mastication to the underlying tissues by absorbing some of the masticatory forces. The study aimed to evaluate the brushing simulation influence on the surface roughness property of soft-tissue liners. A total of eight samples of Avue brand soft-tissue liners with the composition of varnish base and varnish catalyst were suspended into a standard template extracted and numbered sequentially and surface roughness was calculated using a stylus profilometer. A total of 30,000 cycles brushing were done, where the first group samples were brushed with Colgate toothpaste and the second group brushed with Dabur Red toothpaste using a toothbrush simulator (ZM3.8 SD Mechatronik). The data of both pre- and postbrushing values were recorded manually and statistically uploaded on SPSS software version 22 and values were represented in clustered bar graph forms. The significance value of Ra was 0.321. The significance value of Rq was 0.211. The significance value of Rz was 0.354, hence statistically, insignificant. In the present study, the surface roughness of soft-tissue liners is reduced to a minimal extent after brushing simulation.

Comparative analysis of effect of fruit juices on surface roughness of bulk fill and flowable composite material.

Resin-based composites have been widely used to reconstruct anterior and posterior teeth, as dentistry has progressed and there has been an increasing interest in the creation of suitable materials to replace damaged tooth tissue. The aim of the study is to compare the effect of fruit juices on the surface roughness of bulk fill and flowable composite restorative material. A total of 8 bulk fill composite and flowable composite resin disc samples were made. These eight samples were tested for surface roughness following immersion in three juices which were pineapple juice, lime juice, orange juice, and distilled water as the control group. They were immersed at room temperature for 7 days. Surface roughness was evaluated by the Mitutoyo SJ-310 contact profilometer. It showed that there was a decrease in the Ra value of flowable composite when compared to bulk fill composite. Rq and Rz values were more for the flowable composite resin group. Flowable composite resin samples had more surface roughness than bulk fill dental composite restorative material after exposure to pineapple, lime, and orange juices.

Evaluation of flexural strength of bulk-fill composite resin after immersion in fruit juices: An in vitro study.

Resin-based composites are increasingly employed in dental restorations due to their esthetics. Flexural strength is the characteristic feature of a substance, and it can be described as the stress present in the material just before it renders in a flexure test. The purpose of this study was to determine the flexural strength of a bulk-fill composite following immersion in fruit juices. Ten samples of bulk-fill type composite filling material were created, with four samples from Restofill (Group 1) and four samples from Ivoclar Vivadent (Group 2). Out of which, four specimens of each brand were included for immersion in fruit juices; two specimens were kept as control. The eight samples were put through a flexural strength test, with four remaining as controls, before being measured for maximum force and displacement on the Instron E3000 universal testing equipment. SPSS version 23 (IBM SPSS Statistics for Windows, Version 23.0. Armonk, NY: IBM Corp.) was used to examine the calculated flexural strength. The composite Ivoclar has a mean flexural strength of 20.52, whereas the composite Restofill has a mean flexural strength of 20.55. The P value for the independent sample t-test between the two groups, Ivoclar and Restofill, was 0.089 (>0.05), which is statistically insignificant. It is clear from this research that the bulk-fill composite resin Ivoclar has a low flexural strength when compared to the sample Restofill after immersion in fruit juices.

Effect of thermocycling on the flexural strength of two different composite filling materials: An in vitro study.

Flexural strength is the bend strength or stress which causes failure in bending of the material. Composite is the widely used restorative material in the era of esthetic dentistry as it provides better esthetic and mechanical support for both posterior and anterior teeth. The term "thermocycling" refers to the process of changing temperatures in the mouth. Thus, the aim of the study was to determine the effect of thermocycling on flexural strength in two different composite filling materials. Twelve samples of packable type composite filling material, among which four samples prepared were from Restofill l (Group 1) and four were prepared from Ivoclar Vivadent (Group 2) for the study. Bar-shaped composite resin specimens were prepared with dimensions of 2 mm × 2 mm × 25 mm. Then, the eight samples were subjected to a thermocycling process and four left as control. This was followed by the determination of maximum force by a universal testing machine, and then, the collected data were used to determine flexural strength using the formula. The determining flexural strength was analyzed using SPSS version 23.0 by Independent sample t-test. The mean flexural strength of thermocycled Restofill composite filling material is 6.73, whereas the nonthermocycled Restofill sample showed 5.58 and the mean flexural strength of thermocycled Ivoclar Vivadent composite filling material was 5.08. The difference was not statistically significant with P = 0.978 >0.05. The current study concludes that the flexural strength of the Restofill composite (Group 1) was higher than the Ivoclar composite (Group 2). Hence, thermocycling affects the flexural strength of composite resin.

Effect of carbonated beverages on the color stability of bulk and flowable composite resin.

Tooth discoloration is considered as one of the most common dental problems among people, and in dentistry, the most common cases are claimed after the restoration. Therefore, in this research, we aim to evaluate the effect of carbonated beverages on the color stability of bulk and flowable composite resin. For the study, 12 composite disc samples were made using the standard dimensions of 10 mm diameter and 2 mm thick. To find the color stability, we used a VITA Easyshade spectrophotometer. We used two different composites of bulk fill and flowable composite resin; the composite brand we used was Tetric ecom plus; as an immersion medium, we used two different carbonated beverages, and the chosen beverages were Appy Fizz and 7Up. 24-h and 7-day postimmersion color stability was evaluated. In the results of postimmersion, we have found the Delta E value for 24 h immersion of flowable and bulk fill composite as 5.8115 and 7.4378, respectively; similarly, the Delta E value for 7 days immersion of flowable and bulk fill composite was 9.9559 and 10.1028, respectively. Using the independent "t"-test, we found that the significance is 0.633 and 0.328, which was statistically not significant. In the present study, when immersed in Appy Fizz juice and 7Up juice, bulk fill composite resins have shown greater discoloration when compared to flowable composite resin material. Thus, the flowable composite resin samples were more color stable.

Mutations causing Lopes-Maciel-Rodan syndrome are huntingtin hypomorphs.

Huntington's disease pathogenesis involves a genetic gain-of-function toxicity mechanism triggered by the expanded HTT CAG repeat. Current therapeutic efforts aim to suppress expression of total or mutant huntingtin, though the relationship of huntingtin's normal activities to the gain-of-function mechanism and what the effects of huntingtin-lowering might be are unclear. Here, we have re-investigated a rare family segregating two presumed HTT loss-of-function (LoF) variants associated with the developmental disorder, Lopes-Maciel-Rodan syndrome (LOMARS), using whole-genome sequencing of DNA from cell lines, in conjunction with analysis of mRNA and protein expression. Our findings correct the muddled annotation of these HTT variants, reaffirm they are the genetic cause of the LOMARS phenotype and demonstrate that each variant is a huntingtin hypomorphic mutation. The NM_002111.8: c.4469+1G>A splice donor variant results in aberrant (exon 34) splicing and severely reduced mRNA, whereas, surprisingly, the NM_002111.8: c.8157T>A NP_002102.4: Phe2719Leu missense variant results in abnormally rapid turnover of the Leu2719 huntingtin protein. Thus, although rare and subject to an as yet unknown LoF intolerance at the population level, bona fide HTT LoF variants can be transmitted by normal individuals leading to severe consequences in compound heterozygotes due to huntingtin deficiency.

Promotion of somatic CAG repeat expansion by Fan1 knock-out in Huntington's disease knock-in mice is blocked by Mlh1 knock-out.

Recent genome-wide association studies of age-at-onset in Huntington's disease (HD) point to distinct modes of potential disease modification: altering the rate of somatic expansion of the HTT CAG repeat or altering the resulting CAG threshold length-triggered toxicity process. Here, we evaluated the mouse orthologs of two HD age-at-onset modifier genes, FAN1 and RRM2B, for an influence on somatic instability of the expanded CAG repeat in Htt CAG knock-in mice. Fan1 knock-out increased somatic expansion of Htt CAG repeats, in the juvenile- and the adult-onset HD ranges, whereas knock-out of Rrm2b did not greatly alter somatic Htt CAG repeat instability. Simultaneous knock-out of Mlh1, the ortholog of a third HD age-at-onset modifier gene (MLH1), which suppresses somatic expansion of the Htt knock-in CAG repeat, blocked the Fan1 knock-out-induced acceleration of somatic CAG expansion. This genetic interaction indicates that functional MLH1 is required for the CAG repeat destabilizing effect of FAN1 loss. Thus, in HD, it is uncertain whether the RRM2B modifier effect on timing of onset may be due to a DNA instability mechanism. In contrast, the FAN1 modifier effects reveal that functional FAN1 acts to suppress somatic CAG repeat expansion, likely in genetic interaction with other DNA instability modifiers whose combined effects can hasten or delay onset and other CAG repeat length-driven phenotypes.

Patterns of CAG repeat instability in the central nervous system and periphery in Huntington's disease and in spinocerebellar ataxia type 1.

The expanded HTT CAG repeat causing Huntington's disease (HD) exhibits somatic expansion proposed to drive the rate of disease onset by eliciting a pathological process that ultimately claims vulnerable cells. To gain insight into somatic expansion in humans, we performed comprehensive quantitative analyses of CAG expansion in ~50 central nervous system (CNS) and peripheral postmortem tissues from seven adult-onset and one juvenile-onset HD individual. We also assessed ATXN1 CAG repeat expansion in brain regions of an individual with a neurologically and pathologically distinct repeat expansion disorder, spinocerebellar ataxia type 1 (SCA1). Our findings reveal similar profiles of tissue instability in all HD individuals, which, notably, were also apparent in the SCA1 individual. CAG expansion was observed in all tissues, but to different degrees, with multiple cortical regions and neostriatum tending to have the greatest instability in the CNS, and liver in the periphery. These patterns indicate different propensities for CAG expansion contributed by disease locus-independent trans-factors and demonstrate that expansion per se is not sufficient to cause cell type or disease-specific pathology. Rather, pathology may reflect distinct toxic processes triggered by different repeat lengths across cell types and diseases. We also find that the HTT CAG length-dependent expansion propensity of an individual is reflected in all tissues and in cerebrospinal fluid. Our data indicate that peripheral cells may be a useful source to measure CAG expansion in biomarker assays for therapeutic efforts, prompting efforts to dissect underlying mechanisms of expansion that may differ between the brain and periphery.

Genetic and Functional Analyses Point to FAN1 as the Source of Multiple Huntington Disease Modifier Effects.

A recent genome-wide association study of Huntington disease (HD) implicated genes involved in DNA maintenance processes as modifiers of onset, including multiple genome-wide significant signals in a chr15 region containing the DNA repair gene Fanconi-Associated Nuclease 1 (FAN1). Here, we have carried out detailed genetic, molecular, and cellular investigation of the modifiers at this locus. We find that missense changes within or near the DNA-binding domain (p.Arg507His and p.Arg377Trp) reduce FAN1's DNA-binding activity and its capacity to rescue mitomycin C-induced cytotoxicity, accounting for two infrequent onset-hastening modifier signals. We also idenified a third onset-hastening modifier signal whose mechanism of action remains uncertain but does not involve an amino acid change in FAN1. We present additional evidence that a frequent onset-delaying modifier signal does not alter FAN1 coding sequence but is associated with increased FAN1 mRNA expression in the cerebral cortex. Consistent with these findings and other cellular overexpression and/or suppression studies, knockout of FAN1 increased CAG repeat expansion in HD-induced pluripotent stem cells. Together, these studies support the process of somatic CAG repeat expansion as a therapeutic target in HD, and they clearly indicate that multiple genetic variations act by different means through FAN1 to influence HD onset in a manner that is largely additive, except in the rare circumstance that two onset-hastening alleles are present. Thus, an individual's particular combination of FAN1 haplotypes may influence their suitability for HD clinical trials, particularly if the therapeutic agent aims to reduce CAG repeat instability.