-
West African Journal of Medicine Oct 2023Caries is controlled by several factors including exposure to diets rich in carbohydrates, tooth susceptibility, and the presence of some oral flora bacteria such as...
BACKGROUND
Caries is controlled by several factors including exposure to diets rich in carbohydrates, tooth susceptibility, and the presence of some oral flora bacteria such as Streptococcus mutans (S. mutans) and Lactobacilli sp. Tooth demineralisation occurs when the pH in the oral cavity is lower than the critical pH of 5.5 which occurs because of the production of acid by the acidogenic bacteria in the oral flora when they break down sugars (substrate) for energy.
OBJECTIVE
The objective of this study was to determine the salivary Streptococcus mutans and Lactobacillus counts and their association with resting pH of saliva and dental caries in pre-school children in Lagos.
MATERIALSAND METHODS
Fifty preschoolers with and without caries were recruited from the dental clinic and staff primary school in Lagos University Teaching Hospital, Idi-araba respectively. Saliva was collected in Thioglycollate media. The resting pH of the saliva was measured immediately in the clinic with a pH meter (Jenway pH meter, PHS 25). In the laboratory, the samples were streaked on Mitis salivarius bacitracin agar (MSB) and Rogosa agar for S. mutans and Lactobacillus respectively and incubated anaerobically for 48 hours at 37°C. Biochemical tests and morphological characteristics of colonies were used to identify S. mutans and Lactobacillus.
RESULTS
The children were aged between 45 to 71 months with a mean age of 56.66 7.17 months. The mean age of the caries-free group was 55.48 7.57 months and that of caries active group was 57.84 6.76 months. The caries-active subjects recorded significantly higher bacterial counts of S. mutans and Lactobacillus compared to the cariesfree subjects. Streptococcus mutans and Lactobacillus showed a negative and highly significant correlation with resting pH (r = - 0.38 and r = - 0.32 value respectively).
CONCLUSION
The resting pH of saliva in both groups was within normal values. Streptococcus mutans and Lactobacillus counts were significantly inversely correlated to the resting pH value of saliva. Streptococcus mutans and Lactobacillus counts were significantly higher in the caries active group.
CONTEXTE
La carie est contrôlée par plusieurs facteurs dont l'exposition à des régimes riches en glucides, la sensibilité des dents et la présence de certaines bactéries de la flore buccale telles que Streptococcus mutans (S. mutans) et Lactobacilli sp.. La déminéralisation des dents se produit lorsque le pH dans la cavité buccale est inférieur au pH critique de 5,5 qui se produit à la suite de la production d'acide par les bactéries acidurogènes dans la flore buccale lorsqu'elles décomposent les sucres (substrat) pour l'énergie.
BUT ET OBJECTIF
L'objectif de cette étude était de déterminer le nombre de Streptococcus mutans et de Lactobacillus et leur association avec le pH au repos de la salive et des caries dentaires chez les enfants d'âge préscolaire à Lagos.
MATÉRIEL ET MÉTHODES
Cinquante enfants d'âge préscolaire avec et sans caries ont été recrutés respectivement à la clinique dentaire et à l'école primaire du personnel de l'hôpital universitaire de Lagos, Idiaraba. La salive a été recueillie dans un milieu au thioglycolate. Le pH au repos de la salive a été mesuré immédiatement en clinique avec un pHmètre (Jenway pH meter, PHS 25).Au laboratoire, les échantillons ont été striés sur gélose bacitracine Mitis salivarius (MSB) et gélose Rogosa pour S. mutans et Lactobacillus respectivement et incubés en anaérobiose pendant 48 heures à 37°C. Des tests biochimiques et des caractéristiques morphologiques des colonies ont été utilisés pour identifier S. mutans et Lactobacillus.
RÉSULTATS
Les enfants étaient âgés de 45 à 71 mois avec un âge moyen de 56,66 ± 7,17 mois. L'âge moyen du groupe sans carie était de 55,48 ± 7,57 mois et celui du groupe avec carie active était de 57,84 ± 6,76 mois. Les sujets actifs carieux ont enregistré un nombre de bactéries significativement plus élevé de S. mutans et Lactobacillus par rapport aux sujets sans caries. Streptococcus mutans et Lactobacillus ont montré une corrélation négative et hautement significative avec la valeur du pH au repos (r = - 0.38 et r = - 0.32 respectivement) .
CONCLUSION
Le pH au repos de la salive dans les deux groupes était dans les valeurs normales. Les numérations de Streptococcus mutans et de Lactobacillus étaient significativement inversement corrélées à la valeur du pH de la salive au repos. Les numérations de Streptococcus mutans et de Lactobacillus étaient significativement plus élevées dans le groupe actif carieux.
MOTS-CLÉS
Numération bactérienne, Streptococcus mutans, Lactobacillus, pH delasalive,Enfants d'âgepréscolaire.
Topics: Humans; Child, Preschool; Child; Streptococcus mutans; Saliva; Agar; Dental Caries; Nigeria; Cyclophosphamide; Doxorubicin
PubMed: 37906512
DOI: No ID Found -
Angewandte Chemie (International Ed. in... Mar 2021Monitoring the pH in tumor lesions provides abundant physiological information. However, currently developed pH sensors only achieve sensitive detection in the settled...
Monitoring the pH in tumor lesions provides abundant physiological information. However, currently developed pH sensors only achieve sensitive detection in the settled response region around the pH transition point (pH ). To realize tumor pH monitoring with high sensitivity within a wider response region, reported here are serial pH adjustable sensors (pTAS) that simply regulate the component ratio of second near-infrared (NIR-II) emission aza-BODIPY (NAB) donor and pH sensitive rhodamine-based pre-acceptor (NRh) in Förster resonance energy transfer system. Combining the pH response regions of pTAS, a twofold widened pH detection range (6.11-7.22) is obtained compared to the pH settled sensor (6.38-6.94). With an adjustable pH , in vivo tumor pH increase and decrease processes could be dynamically visualized through dual-channel ratiometric bioimaging within the NIR-II window, with a coefficient of variation under 1 % compared to the standard pH meter.
Topics: Animals; Boron Compounds; Cell Line, Tumor; Female; Fluorescence Resonance Energy Transfer; Fluorescent Dyes; Hydrogen-Ion Concentration; Mice, Nude; Monitoring, Physiologic; Neoplasms; Rhodamines; Tumor Microenvironment; Mice
PubMed: 33300662
DOI: 10.1002/anie.202012021 -
Sleep Medicine Mar 2023
Topics: Humans; Polysomnography; Electric Impedance; Sleep Apnea, Obstructive; Continuous Positive Airway Pressure; Hydrogen-Ion Concentration
PubMed: 36724566
DOI: 10.1016/j.sleep.2022.11.043 -
Neuropsychologia Nov 2017Musical sounds, along with speech, are the most prominent sounds in our daily lives. They are highly dynamic, yet well structured in the temporal domain in a...
Musical sounds, along with speech, are the most prominent sounds in our daily lives. They are highly dynamic, yet well structured in the temporal domain in a hierarchical manner. The temporal structures enhance the predictability of musical sounds. Western music provides an excellent example: while time intervals between musical notes are highly variable, underlying beats can be realized. The beat-level temporal structure provides a sense of regular pulses. Beats can be further organized into units, giving the percept of alternating strong and weak beats (i.e. metrical structure or meter). Examining neural processing at the meter level offers a unique opportunity to understand how the human brain extracts temporal patterns, predicts future stimuli and optimizes neural resources for processing. The present study addresses two important questions regarding meter processing, using the mismatch negativity (MMN) obtained with electroencephalography (EEG): 1) how tempo (fast vs. slow) and type of metrical structure (duple: two beats per unit vs. triple: three beats per unit) affect the neural processing of metrical structure in non-musically trained individuals, and 2) how early music training modulates the neural processing of metrical structure. Metrical structures were established by patterns of consecutive strong and weak tones (Standard) with occasional violations that disrupted and reset the structure (Deviant). Twenty non-musicians listened passively to these tones while their neural activities were recorded. MMN indexed the neural sensitivity to the meter violations. Results suggested that MMNs were larger for fast tempo and for triple meter conditions. Further, 20 musically trained individuals were tested using the same methods and the results were compared to the non-musicians. While tempo and meter type similarly influenced MMNs in both groups, musicians overall exhibited significantly reduced MMNs, compared to their non-musician counterparts. Further analyses indicated that the reduction was driven by responses to sounds that defined the structure (Standard), not by responses to Deviants. We argue that musicians maintain a more accurate and efficient mental model for metrical structures, which incorporates occasional disruptions using significantly fewer neural resources.
Topics: Acoustic Stimulation; Adult; Auditory Perception; Brain; Electroencephalography; Evoked Potentials, Auditory; Female; Humans; Male; Music; Young Adult
PubMed: 28987905
DOI: 10.1016/j.neuropsychologia.2017.10.007 -
Transplantation Proceedings May 2019After its initial difficulties were overcome, lung transplantation became an accepted and effective treatment for end-stage lung disease. Patients can take part in...
BACKGROUND
After its initial difficulties were overcome, lung transplantation became an accepted and effective treatment for end-stage lung disease. Patients can take part in almost all kinds of sports after lung transplantation, including high-altitude mountaineering, which is an extreme sport even for healthy individuals. Several articles have been published about high-altitude tolerance of transplanted patients. However, this was the first high-altitude expedition that included only lung transplant patients.
METHODS
The Vienna lung transplantation team organized an expedition in 2017 to conquer the peak of Mount Kilimanjaro, which consisted of 10 lung transplanted patients and 24 accompanying medical personnel. The participants were tested before and several times during the hike to evaluate their general and cardiopulmonary status, the severity of altitude sickness, and radio-morphologic changes. The results of the lung transplanted patients were compared to the results of their healthy companions.
RESULTS
The group started at 2360 meters and reached the 5895-meter-high summit of Mount Kilimanjaro after 6 days on June 18, 2017. Eight transplant patients and 24 escorting medical personnel reached the peak. This means that the success rate was 94%, which is significantly higher than the reported 85% for this route. The 2 transplant patients who did not make the summit turned back on the first and second day because they lacked the necessary fitness for the trip. We did not see a significant difference in the results regarding cardiopulmonary status or the severity of altitude sickness, although we observed mildly higher blood pressure and altitude sickness score results in the lung transplant group.
CONCLUSION
Based on our experiences, we can state that a stable patient after lung transplantation who attains the necessary physical fitness can achieve similar or even better physical results than an average healthy individual.
Topics: Adult; Altitude; Female; Humans; Lung; Lung Transplantation; Male; Middle Aged; Mountaineering; Tanzania; Transplant Recipients
PubMed: 31101210
DOI: 10.1016/j.transproceed.2019.04.004 -
PloS One 2020Human height is a simple measure with great applicability. Usually, stadiometers are used to measure height accurately. However, these may be impractical to transport...
BACKGROUND
Human height is a simple measure with great applicability. Usually, stadiometers are used to measure height accurately. However, these may be impractical to transport and expensive. Therefore, we developed a portable and low-cost laser height metre (LHM).
OBJECTIVE
We aimed to (1) determine intrarater and interrater reliability of our LHM and compare it to a wall-fixed stadiometer, (2) examine its agreement with the same stadiometer, and (3) determine the minimum number of recordings needed to obtain an accurate and reliable height measurement using the LHM.
METHODS
We recruited 32 participants (18+ years)-both men and women. Two raters performed assessments on the same day blinded to each other and their reference standard measurements. We calculated intraclass correlation coefficient (ICC), coefficient of variation (CV), standard error of measurement (SEM), and Bland-Altman plots with limits of agreement (LOA).
RESULTS
For both the LHM and stadiometer, we found ICC values of 0.99-1.00 (95% CI: 0.997-1.000) for both intrarater and interrater reliability. Regarding LHM intrarater reliability, SEM, CV, and LOA were 0.34 cm, 0.16%, and -1.07 to 0.73 cm, respectively. In terms of LHM interrater reliability, SEM, CV, and LOA were 0.27 cm, 0.12%, and -0.32 to 0.84 cm, respectively. As to agreement with stadiometers using one measurement, the mean difference was -0.14 cm and LOA ranged from -0.81 to 0.77 cm.
CONCLUSION
A portable and low-cost LHM, for measuring body height once, showed an excellent reproducibility within and between raters along with an acceptable agreement with a stadiometer thereby representing a suitable alternative.
Topics: Adult; Body Height; Female; Humans; Lasers; Male; Mobile Applications; Reproducibility of Results; Young Adult
PubMed: 32267891
DOI: 10.1371/journal.pone.0231449 -
Mikrochimica Acta Jan 2021A simple and feasible pH meter-based immunoassay is reported for detection of C-reactive protein (CRP) using glucose oxidase (GOD)-conjugated dendrimer loaded with...
A simple and feasible pH meter-based immunoassay is reported for detection of C-reactive protein (CRP) using glucose oxidase (GOD)-conjugated dendrimer loaded with platinum nanozyme. Initially, platinum nanozymes were loaded into the dendrimers through an in situ synthetic method. Then, GOD and monoclonal anti-CRP antibody with a high molar ratio were covalently conjugated onto carboxylated dendrimers via typical carbodiimide coupling. The immunoreaction was carried out with a competitive mode in a CRP-coated microplate. Along with formation of immunocomplex, the added glucose was oxidized into gluconic acid and hydrogen peroxide by GOD, and the latter was further decomposed by platinum nanozyme, thus accelerating chemical reaction in the positive direction. The produced gluconic acid changed the pH of detection solution, which was determined using a handheld pH meter. Under optimum conditions, the pH meter-based immunoassay gave a good signal toward target CRP from 0.01 to 100 ng mL. The limit of detection was 5.9 pg mL. An intermediate precision ≤ 11.2% was acquired with batch-to-batch identification. No nonspecific adsorption was observed during a series of procedures to detect target CRP, and the cross-reaction against other biomarkers was very low. Importantly, our system gave well-matched results for analysis of human serum samples relative to a referenced ELISA kit.Graphical abstract.
Topics: Antibodies, Immobilized; Antibodies, Monoclonal; C-Reactive Protein; Catalysis; Dendrimers; Glucose Oxidase; Humans; Hydrogen Peroxide; Hydrogen-Ion Concentration; Immunoassay; Limit of Detection; Metal Nanoparticles; Oxidation-Reduction; Platinum; Reproducibility of Results
PubMed: 33389237
DOI: 10.1007/s00604-020-04687-9 -
Caries Research 2017Evaluating the physiochemical processes at the tooth surface/bacteria interface is important for elucidating the etiology of dental caries. This study aimed to compare...
Evaluating the physiochemical processes at the tooth surface/bacteria interface is important for elucidating the etiology of dental caries. This study aimed to compare the mineral solubility and protein degradation of coronal enamel (CE) and root dentin (RD), and investigate the involvement of dissolved components in bacteria-induced pH changes using a model of tooth/bacteria interface. An experimental apparatus forming a well was made of polymethyl methacrylate, and a bovine tooth (CE or RD) specimen was fixed at the bottom of the well. A miniature pH electrode was placed on the tooth, and Streptococcus mutans NCTC 10449 cells, grown in 0.5% glucose-containing complex medium, were packed into the well. The pH at the tooth/S. mutans interface was monitored continuously for 120 min after the addition of 0.5% glucose at 37°C. S. mutans cells were recovered from the wells, and the amounts of lactate and calcium were measured using a portable lactate meter and a fluorescent dye, respectively. Proteolytic activity was also evaluated fluorometrically. The pH of the RD/S. mutans interface was significantly higher than that of the CE/S. mutans interface (30 min: 6.37 ± 0.12 vs. 6.18 ± 0.11, 60 min: 6.08 ± 0.14 vs. 5.66 ± 0.27, 90 min: 5.49 ± 0.24 vs. 5.14 ± 0.22, p < 0.05). Greater amounts of calcium were dissolved from RD (3.19 ± 0.74 µg/mL) than from CE (1.84 ± 0.68 µg/mL; p < 0.05), while similar amounts of lactate were produced. Proteolytic activity was not detected at any of the interfaces. These results indicate that RD is more soluble to bacteria-induced acidification than CE. This method can contribute to the evaluation and development of caries-preventive materials.
Topics: Animals; Cattle; Dental Enamel; Dentin; Hydrogen-Ion Concentration; In Vitro Techniques; Solubility; Streptococcus mutans; Surface Properties; Tooth Crown; Tooth Root
PubMed: 28147347
DOI: 10.1159/000454781 -
Scientific Reports Jul 2020Fluorescent pH biosensors have gained importance owing to their low cost utilization in real time monitoring of biological and food samples in comparison to conventional...
Fluorescent pH biosensors have gained importance owing to their low cost utilization in real time monitoring of biological and food samples in comparison to conventional pH meters. The research reports a novel method of ultrasonic atomization for developing a fluorescent pH sensor for real-time analysis made of Fluorescein isothiocyanate (FITC)-dextran/FITC-dextran-Tris (2, 2'-bipyridyl) dichlororuthenium (II) hexahydrate as indicator and reference fluorophores, respectively. The process of ultrasonic atomization ensures formation of monodisperse dye immobilized alginate microspheres ensuring efficient pH sensing. The developed biosensor was tested on milk samples, which has a short life span and shows a significant fall in pH with time due to microbial spoilage. The proposed biosensor showed a linear range of pH 4-8 (R between 0.96-0.99 for different single/dual fluorophore biosensors) which suitably cover the pH of milk during the entire storage period and spoilage. The % recovery for predicted pH falls between 90-110% compared against standard pH meter, indicating a good accuracy of estimation and low turnaround time (10 min). Thus, real-time monitoring using fluorescent pH biosensor for milk samples may profoundly improve the economics of losses occurring in processing and storage with capability of in-package continuous quality assessment.
PubMed: 32616901
DOI: 10.1038/s41598-020-68005-2 -
BMJ Paediatrics Open 2019Gut microbiota plays an important role in the growth of children. The gut of children with optimum growth is enriched in certain species, especially and and ommensal...
BACKGROUND
Gut microbiota plays an important role in the growth of children. The gut of children with optimum growth is enriched in certain species, especially and and ommensal both contribute to formation of acidic stool, and an elevated faecal pH indicates reduction of these species in the gut. The purpose of the study was to investigate the association of faecal pH with childhood stunting.
METHODS
In this cross-sectional study, 100 children with length-for-age Z score (LAZ) <-1 aged between 12 and 18 months were enrolled from the ongoing Bangladesh Environmental Enteric Dysfunction study conducted in Dhaka, Bangladesh. LAZ was measured by anthropometry and data on factors affecting linear growth were recorded. Faecal pH measurement was done using pH metre on freshly collected non-diarrhoeal faecal samples following standard procedure. Multiple quantile regression was done to quantify the relation between faecal pH and LAZ scores.
RESULTS
The mean LAZ and faecal pH of the children were -2.12±0.80 and 5.84±1.11, respectively. Pearson correlation analysis showed a statistically significant negative correlation between stool pH and the LAZ scores (p<0.01). After inclusion of other factors affecting linear growth into the regression model, a statistically significant inverse association was observed between faecal pH and LAZ score (p<0.01).
CONCLUSION
Elevated faecal pH was found to have a significant association with stunted growth. As an indicator of gut microbiota status, faecal pH might have emerged as a possible indirect determinant of childhood stunting.
TRIAL REGISTRATION NUMBER
NCT02812615.
PubMed: 31646200
DOI: 10.1136/bmjpo-2019-000549