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Polymers Aug 2023To measure the flexural strength (FS) of bulk-fill resin composites and assess their long-term water absorption and solubility properties with and without the inclusion...
OBJECTIVE
To measure the flexural strength (FS) of bulk-fill resin composites and assess their long-term water absorption and solubility properties with and without the inclusion of short glass fibres.
METHODS
One resin composite, everX Flow with fibres, and four commercially available bulk-fill composites without fibres, namely, PALFIQUE, Activa, SDR Plus, and Filtek Bulk Fill One, were tested. Six specimens (2 × 2 × 25 mm) were fabricated for each material and stored in water for 1 day and 30 days to measure the flexural strength using a three-point bending test. To evaluate water absorption and solubility, circular disks measuring 15 × 2 mm (n = 5) were immersed in water for 60 days, and their weights were recorded periodically. After 60 days, the specimens were dried for an additional 21 days to determine solubility.
RESULTS
Flexural strength values ranged from 101.7 to 149.1 MPa. Significant distinctions were observed among the resin composites at the onset of the study ( < 0.05). The highest FS value was identified in everX Flow, while ACT exhibited the lowest ( < 0.05). However, the flexural strength values exhibited a significant decrease with increased storage time ( < 0.05), except for ACT, which demonstrated a noteworthy increase. Concerning water absorption and solubility, ACT displayed the highest absorption, while the range of solubility varied from -0.88 to 5.8 μg/mm. ACT also had the highest solubility, whereas everX Flow exhibited negative solubility.
SIGNIFICANCE
The addition of short fibres, along with potential differences in matrix composition, enhanced the flexural strength of everX Flow. However, the substantial reduction in flexural strength observed in everX Flow and SDR following exposure to water corroborates the manufacturers' recommendation to apply a conventional resin composite cap on these materials.
PubMed: 37631507
DOI: 10.3390/polym15163452 -
International Journal of Neonatal... Aug 2023A universal screening research study was conducted in six hospitals to identify the clinical sensitivity of polymerase chain reaction (PCR) testing on newborn dried...
A universal screening research study was conducted in six hospitals to identify the clinical sensitivity of polymerase chain reaction (PCR) testing on newborn dried blood spots (DBSs) versus saliva specimens for the diagnosis of congenital cytomegalovirus (cCMV). CMV DNA positive results from DBSs or saliva were confirmed with urine testing. Findings of several false-positive (FP) saliva PCR results prompted an examination of a possible association with donor milk. Documentation of the frequency of positive saliva results, including both true-positive (TP) and FP status from clinical confirmation, occurred. The frequency of donor milk use was compared for TP and FP cases. Of 22,079 participants tested between 2016 and 2022, 96 had positive saliva results, 15 were determined to be FP, 79 TP, and 2 were excluded for incomplete clinical evaluation. Newborn donor milk use was identified for 18 (19.14%) of all the positive saliva screens. Among the 15 FPs, 11 (73.33%) consumed donor milk compared to 7 of the 79 TPs (8.8%) (OR 28.29, 95% CI 7.10-112.73, < 0.001). While milk bank Holder pasteurization inactivates CMV infectivity, CMV DNA may still be detectable. Due to this possible association, screening programs that undertake testing saliva for CMV DNA may benefit from documenting donor milk use as a potential increased risk for FP results.
PubMed: 37606483
DOI: 10.3390/ijns9030046 -
International Journal of Neonatal... Aug 2023To investigate COVID-19 surveillance among pregnant women, the California Genetic Disease Screening Program conducted a screening performance and seroprevalence...
To investigate COVID-19 surveillance among pregnant women, the California Genetic Disease Screening Program conducted a screening performance and seroprevalence evaluation of maternal SARS-CoV-2 antibodies detected in banked newborn dried blood spots (DBS). We obtained seropositive results for 2890 newborn DBS from cohorts in 2020 and 2021 using Enable Bioscience's Antibody Detection by Agglutination-PCR (ADAP) assay for SARS-CoV-2 antibodies. To infer maternal infection, we linked 312 women with a known laboratory-confirmed COVID-19 episode with their newborn's DBS SARS-CoV02 antibody result. Among 2890 newborns, we detected 453 (15.7%) with SARS-CoV-2 antibodies in their DBS. Monthly snapshot statewide seroprevalence among neonates was 12.2% (95% CI 10.3-14.1%, =1156) in December 2020 and 33.3% (95% CI 29.1-37.4%, = 26) in March 2021. The longest time recorded from COVID-19 infection to a seropositive neonatal result was 11.7 months among the 312 mothers who had an available SARS-CoV-2 PCR test result. Approximately 94% (153/163) of DBS were seropositive when a known maternal infection occurred earlier than 19 days before birth. The estimated relative sensitivity of DBS to identify prevalent maternal infection was 85.1%, specificity 98.5% and PPV 99.2% ( = 312); the sensitivity was lowest during the December 2021 surge when many infections occurred within 19 days of birth. Fifty pre-pandemic specimens (100% seronegative) and 23 twin-pair results (100% concordant) support an intrinsic specificity and PPV of ADAP approaching 100%. Maternal infection surveillance is limited by a time lag prior to delivery, especially during pandemic surges.
PubMed: 37606480
DOI: 10.3390/ijns9030043 -
Marine Drugs Jul 2023The macroalga could be a sustainable and nutritional food resource. However, its composition may vary according to its environment and to processing methods used. To...
The macroalga could be a sustainable and nutritional food resource. However, its composition may vary according to its environment and to processing methods used. To investigate these variations, wild from Quebec were harvested in October 2019 and June 2020, and dried (40 °C, ≃5 h) or stored as frozen controls (-80 °C). The chemical (lipids, proteins, ash, carbohydrates, fibers), mineral (I, K, Na, Ca, Mg, Fe), potential bioactive compound (carotenoids, polyphenols, β-carotene, α-tocopherol) compositions, and the in vitro antioxidant activity and angiotensin-converting enzyme (ACE) inhibition potential of water-soluble extracts were determined. The results suggested a more favorable macroalgae composition in June with a higher content of most nutrients, minerals, and bioactive compounds. October specimens were richer only in carbohydrates and carotenoids. No significant differences in antioxidant or anti-ACE inhibitory activities were found between the two harvest months. The drying process did not significantly impact the chemical and mineral compositions, resulting in only small variations. However, drying had negative impacts on polyphenols and anti-ACE activities in June, and on carotenoids in October. In addition, a concentration effect was observed for carotenoids, β-carotene and α-tocopherol in June. To provide macroalgae of the highest nutritional quality, the drying process for June specimens should be selected.
Topics: alpha-Tocopherol; beta Carotene; Rhodophyta; Antioxidants; Seaweed; Carotenoids; Carbohydrates; Polyphenols
PubMed: 37504923
DOI: 10.3390/md21070392 -
Journal of Pharmacological and... 2023Pharmacokinetic/pharmacodynamic modelling has emerged as a valuable technique for understanding drug exposure and response relationships in drug development....
INTRODUCTION
Pharmacokinetic/pharmacodynamic modelling has emerged as a valuable technique for understanding drug exposure and response relationships in drug development. Pharmacokinetic data are often obtained by taking multiple blood samples, which may disturb physiological parameters and complicate study designs. Wearable automatic blood sampling systems can improve this limitation by collecting dried blood samples at programmable time points without disrupting cardiovascular parameters. It is the objective of this study to evaluate the bioanalysis of DBS in comparison to conventional blood sampling techniques and to optimize the recovery of various compounds spiked into canine blood dried on filter paper tape.
METHODS
Incubated blood samples from Beagle dogs were spiked with 16 different compounds and half of the whole blood sample was centrifuged to obtain plasma. After the dried blood sample drops were dried, liquid chromatography-mass spectrometry methods were used to analyze the samples. The study explored different anticoagulants, sample preparation methods and technical approaches to best determine the compound concentrations in dried blood samples.
RESULTS
With the two anticoagulants tested and using the optimized sample preparation methods and technical approaches we employed, the bioanalysis of dried blood samples can provide equivalent results to conventional blood sampling techniques.
DISCUSSION
Automated blood sampling systems have the potential to provide increased numbers of blood samples, providing substantially more Pharmacokinetic data within safety pharmacology studies without disrupting physiological parameters. They can provide a viable alternative to traditional methods of obtaining blood for various other types of studies or analyses.
Topics: Animals; Dogs; Tandem Mass Spectrometry; Chromatography, Liquid; Blood Specimen Collection; Plasma; Anticoagulants
PubMed: 37482323
DOI: 10.1016/j.vascn.2023.107296 -
Parasites & Vectors Jul 2023As the control of malaria remains heavily dependent on vector management interventions, it is important to understand the impact of these on mosquito populations....
Validation of a method for the dry preservation and rehydration of Anopheles gambiae sensu lato for parity analysis to assess the impact of vector control measures in the field.
BACKGROUND
As the control of malaria remains heavily dependent on vector management interventions, it is important to understand the impact of these on mosquito populations. Age-grading is a valuable tool for this; however, logistical challenges in remote, resource-poor areas make current methodologies difficult to incorporate into clinical trials and routine surveillance. Our aim was to validate a methodology that could be easily implemented in such settings. Using dried mosquito specimens instead of freshly killed ones, we validated the commonly used ovarian tracheation technique for assessing population age structure.
METHODS
Laboratory-reared Anopheles coluzzii mosquitoes with known parity status were dry preserved in silica gel for up to 12 weeks and rehydrated prior to parity assessment. The results were compared to parity results for freshly killed mosquitoes from the same colony. Preserved, field-caught Anopheles gambiae sensu lato (s.l.) from Guinea-Bissau were assessed by three different assessors blinded to each other's scores. An overall index of agreement was calculated using inter-rater reliability of all assessor pairings. The impact of preservation time was investigated using a one-way ANOVA to look for differences in assessor agreement over three time periods.
RESULTS
The parity status was correctly identified for 90% of dry preserved and rehydrated insectary-reared An. coluzzii and for 98% of freshly killed insectary-reared An. coluzzii. The inter-rater reliability was highest (0.94) for freshly killed An. coluzzii. The results for all time points showed excellent strength of agreement between assessors. For field-caught An. gambiae s.l., the overall index of agreement between all three assessors was 0.86 (95% confidence interval 0.78-0.93), indicating almost perfect agreement. There was no significant difference between assessor agreement between time frames.
CONCLUSIONS
Dry preserving and rehydrating Anopheles mosquitoes provides an alternative to using freshly killed mosquitoes to assess the efficacy of a control intervention in remote settings where it is logistically difficult to dissect fresh specimens. This method also provides the flexibility required for parity assessment to be done on larger scales over bigger areas.
Topics: Animals; Anopheles; Fluid Therapy; Mosquito Vectors; Reproducibility of Results
PubMed: 37454212
DOI: 10.1186/s13071-023-05866-2 -
Clinical Chemistry and Laboratory... Jan 2024The collection of capillary blood microsamples via finger-prick has several advantages over traditional blood collection. It is considered convenient and more... (Review)
Review
The collection of capillary blood microsamples via finger-prick has several advantages over traditional blood collection. It is considered convenient and more patient-centric, enabling collection of the sample by the patient at her/his home with subsequent analysis in the lab following postal shipment. Determination of the diabetes biomarker HbA in self-collected microsamples to remotely monitor diabetes patients seems to be a very promising option which could eventually lead to better treatment adaptations and disease control. This is especially convenient/relevant for patients living in areas where venipuncture is impractical, or to support virtual consultations using telemedicine. Over the years, a substantial numbers of reports on HbA and microsampling have been published. However, the heterogeneity of the applied study designs and data evaluation is remarkable. This review provides a general and critical overview of these papers, along with specific points of attention that should be dealt with when aiming at implementing microsampling for reliable HbA determination. We focus on the used (dried) blood microsampling techniques, collection conditions, stability of the microsamples, sample extraction, analytical methods, method validation, correlation studies with conventional venous blood samples and patient satisfaction. Lastly, the possibility of using liquid instead of dried blood microsamples is discussed. Liquid blood microsampling is expected to have similar advantages as dried blood microsampling and several studies suggest it to be a suitable approach to collect samples remotely for subsequent HbA analysis in the lab.
Topics: Humans; Female; Blood Specimen Collection; Dried Blood Spot Testing; Phlebotomy; Diabetes Mellitus
PubMed: 37419657
DOI: 10.1515/cclm-2023-0228 -
Journal of Immunological Methods Aug 2023Dried serum spots that are well prepared can be attractive alternatives to frozen serum samples for shelving specimens in a medical or research center's biobank and...
Dried serum spots that are well prepared can be attractive alternatives to frozen serum samples for shelving specimens in a medical or research center's biobank and mailing freshly prepared serum to specialized laboratories. During the pre-analytical phase, complications can arise which are often challenging to identify or are entirely overlooked. These complications can lead to reproducibility issues, which can be avoided in serum protein analysis by implementing optimized storage and transfer procedures. With a method that ensures accurate loading of filter paper discs with donor or patient serum, a gap in dried serum spot preparation and subsequent serum analysis shall be filled. Pre-punched filter paper discs with a 3 mm diameter are loaded within seconds in a highly reproducible fashion (approximately 10% standard deviation) when fully submerged in 10 μl of serum, named the "Submerge and Dry" protocol. Such prepared dried serum spots can store several hundred micrograms of proteins and other serum components. Serum-borne antigens and antibodies are reproducibly released in 20 μl elution buffer in high yields (approximately 90%). Dried serum spot-stored and eluted antigens kept their epitopes and antibodies their antigen binding abilities as was assessed by SDS-PAGE, 2D gel electrophoresis-based proteomics, and Western blot analysis, suggesting pre-punched filter paper discs as handy solution for serological tests.
Topics: Humans; Reproducibility of Results; Antibodies; Filtration; Paper
PubMed: 37419022
DOI: 10.1016/j.jim.2023.113519 -
Heliyon Jun 2023The disposal of paper mill sludge waste generated by the paper industry is a tough and challenging task. In this work, an attempt is made to develop various value-added...
The disposal of paper mill sludge waste generated by the paper industry is a tough and challenging task. In this work, an attempt is made to develop various value-added products namely bricks, briquettes, ground chakra base, and eco-friendly composites from the secondary paper mill sludge (PMS). The secondary PMS was initially dewatered to remove the moisture content, ground to powder, and mixed with cement, MSand. quarry dust, and fly ash to produce bricks. The brick specimens were tested for compressive strength, water absorption, and efflorescence as per the standards and found to be 5.29 ± 0.11 N/mm, 3.84 ± 0.13% respectively, and have NIL efflorescence. The PMS is mixed with paraffin wax and compressed in a squeeze moulding to form briquettes and observed that the percentage of ash content in the briquette is 66.6% which is less than that of the PMS. Further, a ground chakra base is produced using a slurry of starch and dried in a heater at 60° exhibiting better properties. An eco-friendly composite pottery product was developed by mixing PMS, clay, and starch and tested for breakage.
PubMed: 37416675
DOI: 10.1016/j.heliyon.2023.e17517 -
Simultaneous detection and differentiation of dengue and chikungunya viruses for commercial utility.Virusdisease Jun 2023The diagnosis of Dengue and Chikungunya infections during acute phase is a priority considering emerging pattern and increasing trends of their infections. The present...
The diagnosis of Dengue and Chikungunya infections during acute phase is a priority considering emerging pattern and increasing trends of their infections. The present study describes the commercial development and validation of RT-PCR test for the simultaneous detection of of DEN and CHIK viral RNA in a single tube from human plasma samples. Multistep one step RT-PCR assay was developed and validated for detection and discrimination of DEN and CHIK along with exogenous internal control. The test was evaluated for commercial use using 3 different lots to determine analytical sensitivity, specificity, precision and stability. The external clinical evaluation was performed at NABL accredited lab with known positive and negative Chikungunya and Dengue specimens and comparator assay method. The findings showed that the test could identify CHIK and DEN viral nucleic acid in clinical samples within 80 min, without any cross-reactivity. The analytical detection limit of the test was 1.56 copies/µl for both. The clinical sensitivity and specificity was ≥ 98% and provide a high-throughput and screen up to 90 samples in a single run. It is available in a freeze-dried format and can be used in both the manual and automated platforms. This unique combo test, PathoDetect™ "CHIK DEN Multiplex PCR Kit" enables simultaneous, sensitive, specific detection of DENV and CHIKV and serves as "ready to use" platform for commercial use. It would aid the differential diagnosis as early as day 1 of the infection and facilitate screen-and-treat approach.
PubMed: 37408546
DOI: 10.1007/s13337-023-00822-1