ASSOCIATION BETWEEN THE STREPTOCOCCUS MUTANS BIOFILM FORMATION AND DENTAL CARIES EXPERIENCE AND ANTIBIOTICS RESISTANCE IN ADULT FEMALES

Objectives: The aim of this study was to consider the potential association between the formation of salivary streptococcus biofilms and the incidence of caries, as well as with the occurrence of antibiotic resistance among adult mothers in Sana'a, Yemen. Study design: A total of 261; 25-35 year old females were chosen. Clinical examination of females were performed to estimate dental caries experience with the Silness-Loe index, as well as stimulated saliva were collected to assess biofilm production by the phenotypic method i.e. Tissue culture palate methods (TCPM). Finally, antibiogram susceptibility pattern of isolated S. mutans was done by Kirby-Bauer disc diffusion method for 6 β-Lactam antibiotics (ampicillin, penicillin, amoxicillin, cefotaxime, methicillin and cefazolin) and 4 non β-Lactam antibiotics (clindamycin, erythromycin, lincomycin and vancomycin). Results: When isolated S. mutans were exposed to biofilm detection by TCP method, 31 (12.2%) showed high biofilm formation capacity, 46 (18%) showed moderate biofilm formation capacity, while 184 (72.2%) showed non / weak formation capacity of biofilm. The overall rate of biofilm formation was 30.2%. There was an escalation in the rate of formation of S. mutans biofilms with an increased degree of caries index. The S. mutans biofilms positve showed a higher rate of resistance than non/weak biofilm formation e.g ampicillin (28.6% versus 12.9%, p = 0.002), amoxicillin (77.9% versus 18%, p <0.0001), and penicillin (79.2 % versus 23%, <0.0001) etc. Conclusion: The present study proved that S. mutans is still the major bacteria isolate from the oral cavity, but few persons might not have significant number of S. mutans in oral cavity. The S. mutans biofilm - producers were more able to cause dental caries compared to the S. mutans biofilm-non-producers. Drug resistant factor in the S. mutans isolates was found to be associated with S. mutans biofilm formation. Peer Review History: Received 12 November 2020; Revised 20 Decembe; Accepted 5 January, Available online 15 January 2021 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file: Comments of reviewer(s): Average Peer review marks at initial stage: 6.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Dr. Alfonso Alexander Aguileral, University of Veracruz, Mexico, [email protected] Dr. George Zhu, Tehran University of Medical Sciences, Tehran, Iran, [email protected] Similar Articles: CAUSES FOR EXTRACTION OF PERMANENT TEETH IN GENERAL DENTAL PRACTICES IN YEMEN PREVALENCE OF STAPHYLOCOCCUS AUREUS IN DENTAL INFECTIONS AND THE OCCURRENCE OF MRSA IN ISOLATES

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AN OVERVIEW ON CURRENT REGULATION AND EVALUATION OF BIOCIDAL PRODUCTS

Universal Journal of Pharmaceutical Research ◽

10.22270/ujpr.v4i5.315 ◽

2019 ◽

Author(s):

Aslı ŞAHİNER ◽

Evren ALGIN YAPAR

Keyword(s):

Peer Review ◽

Chemical Substance ◽

Biological Action ◽

Insect Repellents ◽

Biocidal Products ◽

Unique System ◽

Natural Oil ◽

Review Reports ◽

E Mail ◽

Biocidal Product

A biocidal product is a substance or mixture prepared to limit, destroy, neutralize or control the effects of a harmful microorganism, plants and animals. The active substance in a biocidal product can be a natural oil or extract, a chemical substance or a microorganism, virus or fungus. Biocides consist of four main groups: disinfectants, preservatives (wood, paint, etc.), pest control and other type of biocidal products. A biocidal substance can also be added to a product to make the product itself into a biocidal product. These products range from disinfectants, hand sanitizers, preservatives, insect repellents, to rodenticides and insecticides and are used to protect humans, animals, materials and articles by controlling the intended target organism by a chemical or biological action. To make sure the use of biocidal products do not have unacceptable risks for people, animals and the environment, they are regulated to control their marketing, sale and use. In the current study biocidal products have been overviewed in the scope of current European Union regulations, product types and conformity tests. Peer Review History: UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file Average Peer review marks at initial stage: 5.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewer(s) detail: Name: Dr. Barkat Ali Khan Affiliation: Kampala International University , Uganda E-mail: [email protected] Name: Dr. Sally A. El-Zahaby Affiliation: Pharos University in Alexandria, Egypt E-mail: [email protected] Comments of reviewer(s):

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FORMULATION AND EVALUATION OF PHARMACEUTICALY STABLE SERUM OF DUCHESNEA INDICA (ARBENAN)

Universal Journal of Pharmaceutical Research ◽

10.22270/ujpr.v6i1.538 ◽

2021 ◽

Author(s):

A. Mumtihanah Mursyid ◽

Risda Waris

Keyword(s):

Peer Review ◽

Leaf Extract ◽

Ethanolic Extract ◽

Ethanol Extract ◽

Initial Stage ◽

Unique System ◽

Duchesnea Indica ◽

Leaf Powder ◽

Review Reports ◽

Stable Leaf

Objective: Arbenan (Duchesnea indica) plants contain saponins, flavonoids, and tannins which have antioxidant activity. The purpose of this research is to perform formulation and evaluation extract ethanol of Arbenan leaves in the form of serum which is pharmaceutically stable. Method: Arbenan leaf powder was macerated with ethanol solvent, and then left for 3-4 days while stirring repeatedly, and then filtering. Furthermore, the liquid ethanol extract that has been obtained is evaporated using a Rotary Vacum Evaporator was used to evaporate the extract. Prepared extract was used to evaluate various parameters like organoleptics, homogeneity, viscosity, and pH. Result: All formulations were having typical smell, light brown color and a little thick consistency. Formulations of leaf extract of Arabenan with four variations bases have shown to have good stability after stress condition. It can be seen from the evaluation result are organoleptics, homogeneity, viscosity, rheology, and pH. Conclusion: Study concludes that a stable leaf extract of Arabenan can be effectively formulated into a serum by the means of various bases. Peer Review History: Received 8 January 2021; Revised 13 February; Accepted 4 March, Available online 15 March 2021 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file: Reviewer's Comments: Average Peer review marks at initial stage: 5.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewer(s) detail: Dr. Marwa A. A. Fayed, University of Sadat City, Egypt, [email protected] Prof. Dr. Ali Gamal Ahmed Al-kaf, Sana'a university, Yemen, [email protected] Ahmad Najib, Universitas Muslim Indonesia, Makassar, Indonesia, [email protected] Similar Articles: PHYTOCHEMICAL, ANTI-INFLAMMATORY, ANALGESIC, ANTIPYRETIC AND ACUTE TOXICITY OF PSIADIA PUNCTULATA GROWING IN YEMEN ANTIHYPERLIPIDEMIC EFFECT OF THE ETHANOLIC EXTRACT OF SCAEVOLA TACCADA (GAERTN) ROXB. LEAVES ETHNOBOTANY, PHYTOCHEMISTRY AND PHARMACOLOGY OF OCHNA SCHWEINFURTHIANA: A REVIEW

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The Role of Genetic Factors in the Outbreak Mechanism of Dental Caries

Journal of Clinical Pediatric Dentistry ◽

10.17796/1053-4628-42.1.6 ◽

2018 ◽

Vol 42 (1) ◽

pp. 32-36 ◽

Cited By ~ 5

Author(s):

Junko Shimomura-Kuroki ◽

Tomoko Nashida ◽

Yukio Miyagawa ◽

Tsuneo Sekimoto

Keyword(s):

Regression Analysis ◽

Dental Caries ◽

Multiple Regression Analysis ◽

Candidate Genes ◽

Multiple Regression ◽

Permanent Teeth ◽

Caries Experience ◽

Nucleotide Polymorphisms ◽

Streptococcus Sobrinus ◽

Mucosal Cells

Objective: The aim of the present study was to investigate the relationships between cariogenic bacterial infection and single nucleotide polymorphisms (SNPs) in candidate genes associated with dental caries, and to explore the factors related to caries in children.Study design: Children aged 3 to 11 years were selected. Detection of cariogenic bacteria (Streptococcus mutans, Streptococcus oralis, Streptococcus sobrinus and Lactobacillus) from the plaque of each patient, and SNP analyses of five candidate genes (MBL2, TAS2R38, GLUT2, MMP13 and CA6) were performed using DNA isolated from buccal mucosal cells. The dental caries experience in primary and permanent teeth was determined using the decayed, missing and filled teeth (DMFT) index, and the effects of the observed factors on the DMFT value were analyzed by multiple regression analysis. Results: The results of the multiple regression analysis showed that the DMFT value significantly increased in the presence of S. mutans or S. sobrinus (p < 0.001), while the dmft/DMFT value decreased in the presence of nucleobase C in MBL2 (p < 0.05). Conclusion: These results suggest that the MBL2 gene is related to the pathogenesis of dental caries.

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Murein Hydrolase LytF of Streptococcus sanguinis and the Ecological Consequences of Competence Development

Applied and Environmental Microbiology ◽

10.1128/aem.01709-17 ◽

2017 ◽

Vol 83 (24) ◽

Cited By ~ 5

Author(s):

Nyssa Cullin ◽

Sylvio Redanz ◽

Kirsten J. Lampi ◽

Justin Merritt ◽

Jens Kreth

Keyword(s):

Dental Caries ◽

Oral Cavity ◽

Cell Morphology ◽

Biofilm Formation ◽

Oral Bacteria ◽

Tooth Surface ◽

Content Type ◽

Streptococcus Sanguinis ◽

Murein Hydrolase ◽

Biofilm Development

ABSTRACT The overall health of the oral cavity is dependent on proper homeostasis between health-associated bacterial colonizers and bacteria known to promote dental caries. Streptococcus sanguinis is a health-associated commensal organism, a known early colonizer of the acquired tooth pellicle, and is naturally competent. We have shown that LytF, a competence-controlled murein hydrolase, is capable of inducing the release of extracellular DNA (eDNA) from oral bacteria. Precipitated LytF and purified LytF were used as treatments against planktonic cultures and biofilms. Larger amounts of eDNA were released from cultures treated with protein samples containing LytF. Additionally, LytF could affect biofilm formation and cellular morphology. Biofilm formation was significantly decreased in the lytF-complemented strain, in which increased amounts of LytF are present. The same strain also exhibited cell morphology defects in both planktonic cultures and biofilms. Furthermore, the LytF cell morphology phenotype was reproducible in wild-type cells using purified LytF protein. In sum, our findings demonstrate that LytF can induce the release of eDNA from oral bacteria, and they suggest that, without proper regulation of LytF, cells display morphological abnormalities that contribute to biofilm malformation. In the context of the oral biofilm, LytF may play important roles as part of the competence and biofilm development programs, as well as increasing the availability of eDNA. IMPORTANCE Streptococcus sanguinis, a commensal organism in the oral cavity and one of the pioneer colonizers of the tooth surface, is associated with the overall health of the oral environment. Our laboratory showed previously that, under aerobic conditions, S. sanguinis can produce H2O2 to inhibit the growth of bacterial species that promote dental caries. This production of H2O2 by S. sanguinis also induces the release of eDNA, which is essential for proper biofilm formation. Under anaerobic conditions, S. sanguinis does not produce H2O2 but DNA is still released. Determining how S. sanguinis releases DNA is thus essential to understand biofilm formation in the oral cavity.

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Selected Restoration and Tooth Conditions: United States, 1988–1991

Journal of Dental Research ◽

10.1177/002203459607502s06 ◽

1996 ◽

Vol 75 (2_suppl) ◽

pp. 661-671 ◽

Cited By ~ 10

Author(s):

B.A. White ◽

T.F. Albertini ◽

L.J. Brown ◽

D. Larach-Robinson ◽

M. Redford ◽

...

Keyword(s):

Dental Caries ◽

Phase 1 ◽

Permanent Teeth ◽

Caries Experience ◽

Tooth Structure ◽

Health And Nutrition ◽

Dmf Index ◽

Oral Conditions ◽

The Impact ◽

Source Of Information

The DMF index provides one source of information on past and present dental caries experience; however, important limitations hinder its ability to characterize fully the impact of dental caries. The purpose of this paper is to describe a measure of selected restoration and tooth conditions that supplements information from the DMF index and to report on the application of this measure as part of the Third National Health and Nutrition Examination Survey, Phase 1, conducted between 1988 and 1991. Data from this survey were used to estimate the prevalence and severity of selected disaggregated physical and biological oral conditions among dentate adults aged 18 to 74 years. Trained, standardized, and calibrated dentist examiners assessed 28 permanent teeth or tooth spaces for each of 6,767 subjects. Teeth or tooth spaces were classified based on criteria for: defective intracoronal restorations, crowns, or bridges; gross loss of tooth structure associated with a restoration; pulpal involvement; or retained roots. Approximately 40.5%, or 61.6 million, dentate adults had at least one tooth or tooth space that met the criteria. Among all persons, an average of 0.9 teeth or tooth spaces met the criteria for at least one category. Adults with at least one scored tooth or tooth space had an average of 2.2 such teeth or tooth spaces. Data from this assessment supplement information available from the DMF index to provide a broader profile of the impact of dental caries on permanent teeth of US adults.

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The impact of histopathological celiac disease activity on dental enamel defects and dental caries

Journal of Baghdad College of Dentistry ◽

10.26477/jbcd.v32i1.2758 ◽

2020 ◽

Vol 32 (1) ◽

pp. 51-56

Author(s):

Zainab Q Al-Obaidi ◽

Nada J Radhi

Keyword(s):

Celiac Disease ◽

Dental Caries ◽

Disease Activity ◽

Villous Atrophy ◽

Dental Enamel ◽

Permanent Teeth ◽

Caries Experience ◽

Entire Body ◽

Enamel Defects ◽

The Impact

Background: Celiac disease is an autoimmune chronic disease that affects the human’s intestine and subsequently reflects its effect on the entire body health by retardation the absorption and immune mediated complications cause the involvement of oral health. The present study intended to evaluate the impact of the histopathological disease activity upon dental enamel defects and dental caries. Subjects and methods: Forty celiac-diseased patients aged 7-11 years were collected from 3 different teaching hospitals in Baghdad classified by means of the histopathological activity of the intestinal disease according to modified Marsh-Rostami classification. Dental enamel defects were measured by Aine’s classification, while dental caries experience and severity were measured using d1-4mfs/t and D1-4MFS/T. Results: The majority of the sample came with partial villous atrophy of the small intestine (Marsh III-a) and almost half of the sample were with no celiac disease specific dental enamel defects (Aine’s 0), while Aine’s I was the most predominant than Aine’s II. Most missed surfaces due to dental caries in permanent teeth came with Marsh II. Conclusion: The more the severity of celiac disease histopathological activity the more the severity of celiac specific dental enamel defects and the less experienced dental caries. Keywords: Celiac disease, histopathological activity, dental enamel defects, dental caries.

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Green Tea Polyphenol Epigallocatechin-3-Gallate-Stearate Inhibits the Growth of Streptococcus mutans: A Promising New Approach in Caries Prevention

Dentistry Journal ◽

10.3390/dj6030038 ◽

2018 ◽

Vol 6 (3) ◽

pp. 38 ◽

Cited By ~ 10

Author(s):

Amy Melok ◽

Lee Lee ◽

Siti Mohamed Yussof ◽

Tinchun Chu

Keyword(s):

Dental Caries ◽

Oral Cavity ◽

Streptococcus Mutans ◽

Biofilm Formation ◽

Morphological Changes ◽

The United States ◽

Chlorhexidine Gluconate ◽

Log Reduction ◽

Colony Forming Units ◽

Green Tea Polyphenol

Streptococcus mutans (S. mutans) is the main etiological bacteria present in the oral cavity that leads to dental caries. All of the S. mutans in the oral cavity form biofilms that adhere to the surfaces of teeth. Dental caries are infections facilitated by the development of biofilm. An esterified derivative of epigallocatechin-3-gallate (EGCG), epigallocatechin-3-gallate-stearate (EGCG-S), was used in this study to assess its ability to inhibit the growth and biofilm formation of S. mutans. The effect of EGCG-S on bacterial growth was evaluated with colony forming units (CFU) and log reduction; biofilm formation was qualitatively determined by Congo red assay, and quantitatively determined by crystal violet assay, fluorescence-based LIVE/DEAD assays to study the cell viability, and scanning electron microscopy (SEM) was used to evaluate the morphological changes. The results indicated that EGCG-S was able to completely inhibit growth and biofilm formation at concentrations of 250 µg/mL. Its effectiveness was also compared with a commonly prescribed mouthwash in the United States, chlorhexidine gluconate. EGCG-S was shown to be equally effective in reducing S. mutans growth as chlorhexidine gluconate. In conclusion, EGCG-S is potentially an anticariogenic agent by reducing bacterial presence in the oral cavity.

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SUDANESE EXPERIENCE OF HERBAL FORMULAS USED DURING COVID-19 INFECTION

Universal Journal of Pharmaceutical Research ◽

10.22270/ujpr.v5i5.485 ◽

2020 ◽

Author(s):

AzzaAbdelilah Ahmed Mohamed ◽

Mai Abdalla Humaida ◽

Ali Awadallah Saeed

Keyword(s):

Peer Review ◽

Virus Disease ◽

Off Label Use ◽

Review System ◽

Diabetes Therapy ◽

Off Label ◽

Initial Stage ◽

Unique System ◽

Review Reports

Objectives: Corona virus disease 2019 (COVID-19) outbreak is recent worldwide disaster which is considered by the WHO as Public Health Emergency of International Concern (PHEIC). Method: A quick survey was done in Khartoum state for the commonly utilize herbs and the succeeded formulas, 652 people participated in this survey either they use these herbs for themselves or their relative use it during the symptoms of COVID-19. Results: A 652 people participated in the quick survey for the commonly utilized herbs & the succeeded formulas either they use these herbs for themselves or their relative use it during the symptoms of COVID-19. Other products used as additives include (honey,vinegar,sesame oil, olive oil and salt). Conclusion: Sudanese experience that various traditional herbs, usage and different route of administration can effectively alleviate primary symptoms e.g. fever, cough, fatigue and reduce probability of developing severe Conditions. Peer Review History: Received: 8 September 2020; Revised: 7 October; Accepted: 20 October, Available online: 15 November 2020 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file Average Peer review marks at initial stage: 5.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewer(s) detail: Dr. Hebatalla Ibrahim Ahmed Abdel Hameed, Al-Azhar University, Faculty of Pharmacy (Girls), Nasr City, Cairo, Egypt [email protected] Dr. Mohamed Derbali, Faculty of Pharmacy, Monastir, Tunisia, [email protected] Comments of reviewer(s): Similar Articles: THE RISKS AND ADVANTAGES OF ANTI-DIABETES THERAPY IN THE POSITIVE COVID-19 PATIENT EUCALYPTUS ESSENTIAL OIL; AN OFF-LABEL USE TO PROTECT THE WORLD FROM COVID-19 PANDEMIC: REVIEW-BASED HYPOTHESES

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OCCLUSAL CHARACTERISTICS OF THE PRIMARY DENTITION AMONG A SAMPLE OF YEMENI PRE-SCHOOL CHILDREN

Universal Journal of Pharmaceutical Research ◽

10.22270/ujpr.v5i1.359 ◽

2020 ◽

Author(s):

Lamia A.T. Bin Yehia ◽

Khaled A AL-Haddad ◽

Mohammed A Al-labani ◽

Hassan Abdulwahab Al-Shamahy ◽

Hussein M Shaga-aldeen

Keyword(s):

Peer Review ◽

School Children ◽

Intestinal Parasites ◽

Primary Dentition ◽

Class I ◽

Class Iii ◽

Unique System ◽

Potential Risk Factors ◽

Review Reports ◽

E Mail

Objective: The occlusal features change dynamically in the growing children and any disruption in the complex craniofacial growth process may lead to malocclusion, which is a major concern for the pediatric community because of its effects on dental function and beauty, as well as on the child's psyche. The aim of the present study was to study the prevalence of different occlusal traits in the primary dentition of the randomly selected pre-school children from three to five years in the city of Sana’a, Yemen. Methods: The study includes 1106 pre-school children subjected to a dental examination performed in the school premise, using the Foster and Hamilton criteria for occlusal traits. As well as inter- and intra-calibration tests were conducted for assessing the degree of agreeability. Results: Results of the study showed that the Bilateral flush terminal molar relationship was found in 60%, bilateral mesial step in 27.9%, asymmetrical relationship in 8.5% and distal step in 3.5% of tested children. The Bilateral canine class I was detected in 62.8%, asymmetrical relationship (13.6%), class II (12.5%) and class III (11.1%). Normal over-jet (OJ) of 1-3 mm was identified in 39.2%, decreased OJ <1 mm (32.7%) and edge-to-edge (8.8%). Ideal over-bite (OB) of 1-50% was detected in 64.5% and increased OB of > 50% (19.7%). Conclusion: In conclusion theBilateral flush terminal molar, class I canine relationships, normal overjet (OJ) of 1-3mm were the most commonly found sagittal occlusal traits in the current study. Ideal over-bite (OB) of 1-50% were identified in more than half of the children. Peer Review History: Received 2 February 2020; Revised 21 February; Accepted 3 March, Available online 15 March 2020 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 7.0/10 Reviewer(s) detail: Name: Aya Mohammed Mohammed Essawy Affiliation: MTI University- Mokattam, Egypt E-mail: [email protected] Name: Dr. Nada Farrag Affiliation: Misr International University, Egypt E-mail: [email protected] Comments of reviewer(s): Similar Articles: COCCIDIAN INTESTINAL PARASITES AMONG CHILDREN IN AL-TORBAH CITY IN YEMEN: IN COUNTRY WITH HIGH INCIDENCE OF MALNUTRITION EVALUATION OF THE IMMUNE RESPONSE TO POLIO VACCINE IN MALNOURISHED CHILDREN IN SANA'A CITY PREVALENCE AND POTENTIAL RISK FACTORS OF HEPATITIS B VIRUS IN A SAMPLE OF CHILDREN IN TWO SELECTED AREAS IN YEMEN

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Disruption of L-Rhamnose Biosynthesis Results in Severe Growth Defects in Streptococcus mutans

Journal of Bacteriology ◽

10.1128/jb.00728-19 ◽

2019 ◽

Vol 202 (6) ◽

Cited By ~ 1

Author(s):

Andrew P. Bischer ◽

Christopher J. Kovacs ◽

Roberta C. Faustoferri ◽

Robert G. Quivey

Keyword(s):

Cell Wall ◽

Dental Caries ◽

Oral Cavity ◽

Streptococcus Mutans ◽

Biofilm Formation ◽

Etiologic Agent ◽

Growth Defect ◽

Cell Wall Polysaccharide ◽

Content Type ◽

Severe Growth

ABSTRACT The rhamnose-glucose cell wall polysaccharide (RGP) of Streptococcus mutans plays a significant role in cell division, virulence, and stress protection. Prior studies examined function of the RGP using strains carrying deletions in the machinery involved in RGP assembly. In this study, we explored loss of the substrate for RGP, l-rhamnose, via deletion of rmlD (encoding the protein responsible for the terminal step in l-rhamnose biosynthesis). We demonstrate that loss of rhamnose biosynthesis causes a phenotype similar to strains with disrupted RGP assembly (ΔrgpG and ΔrgpF strains). Deletion of rmlD not only caused a severe growth defect under nonstress growth conditions but also elevated susceptibility of the strain to acid and oxidative stress, common conditions found in the oral cavity. A genetic complement of the ΔrmlD strain completely restored wild-type levels of growth, whereas addition of exogenous rhamnose did not. The loss of rhamnose production also significantly disrupted biofilm formation, an important aspect of S. mutans growth in the oral cavity. Further, we demonstrate that loss of either rmlD or rgpG results in ablation of rhamnose content in the S. mutans cell wall. Taken together, these results highlight the importance of rhamnose production in both the fitness and the ability of S. mutans to overcome environmental stresses. IMPORTANCE Streptococcus mutans is a pathogenic bacterium that is the primary etiologic agent of dental caries, a disease that affects billions yearly. Rhamnose biosynthesis is conserved not only in streptococcal species but in other Gram-positive, as well as Gram-negative, organisms. This study highlights the importance of rhamnose biosynthesis in RGP production for protection of the organism against acid and oxidative stresses, the two major stressors that the organism encounters in the oral cavity. Loss of RGP also severely impacts biofilm formation, the first step in the onset of dental caries. The high conservation of the rhamnose synthesis enzymes, as well as their importance in S. mutans and other organisms, makes them favorable antibiotic targets for the treatment of disease.

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