The Antibacterial and Anti-biofilm Traits of the Novel BMAP-27-Melittin Conjugated Peptide Nanoparticle Against Streptococcus mutans: Clinical Isolates from Oral Cavity.

Background & Objective: The spread and development of drug-resistant bacterial strains has prompted the hunt for novel antibacterial polypeptides undergoing conformational changes to confer rapid bactericidal effects. The aim of this study was to evaluate the effect of novel BMAP27-Melittin conjugated peptide- nanoparticle (NP) against Streptococcus mutans as the primary pathogen from subgingival plaques. Methods: Sixty subgingival plaque samples were collected, and 39 S. mutans isolates were identified. The BMAP27-Melittin conjugated peptide was purchased from GenScript Company, USA. Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), Biofilm Inhibitory Concentration (BIC), and Biofilm Eradication Concentration (BEC) of BMAP27-Melittin-NP were calculated using the microtiter method. Results: Thirty-nine infected subjects were reported, including 24 males and 15 females (P=0.299). MIC, MBC, BIC, and BEC of BMAP27-Melittin-NP against S. mutans were 1.8, 2.9, 2.1, and 3.8µg/mL, respectively. The mean MBC, BEC, and BIC values were significantly lower among clinical isolates than S. mutans ATCC 35688 standard strain (P=0.032, 0.001, and 0.001, respectively). Conclusion: BMAP27-Melittin-NP demonstrated significant antibacterial and anti-biofilm effects against clinical isolates of S. mutans which can be considered a promising compound to prevent or treat dental caries and eradicate the oral infections.

Correlation between Clinical and Histopathological Diagnoses in Oral Cavity Lesions: A 12-Year Retrospective Study.

Objective: Proper diagnosis plays a key role in the treatment and prognosis of all diseases. Although histopathological diagnosis is still known as the gold standard, final diagnosis becomes difficult unless precise clinical descriptions are obtained. So, this study aimed to evaluate the concordance of the clinical and histopathological diagnoses of all oral and maxillofacial biopsy specimens in a 12-year duration. Materials and Methods: Archive files and clinical findings related to 3001 patients who had been referred to the Department of Oral Pathology during a 12-year period were reviewed. The recorded information in files included age, sex, lesion's location, clinical and histopathological diagnoses, and specialty of dentists. Results: Out of 3001 cases included and reviewed in this study, 2167 cases (72.2%) were consistent between clinical and histopathologic diagnoses. Age, sex, and clinician's specialty were indicated to have no significant effect on diagnosis (p values = 0.520, 0.310, 0.281, respectively), but location and type of lesion affected that (p values = 0.040 and 0.022, respectively). In regard to location, the highest concordance of clinical and histopathologic diagnoses was observed in mouth floor lesions, and the lowest one was in gingival mucosa. In terms of lesion category, the highest and the lowest concordance rates belonged to white and red lesions and pigmented lesions, respectively. Conclusion: The results of the present study show that the consistency of clinical and histopathological diagnoses was three times more than their inconsistency, and the accuracy of the clinicians was largely acceptable.

Evaluation of Candida albicans biofilm formation on conventional and computer-aided-design/computer-aided manufacturing (CAD/CAM) denture base materials.

Background and Purpose: The human mouth mucosal surface is colonized by indigenous microflora, which normally maintains an ecological balance among different species. However, certain environmental or biological factors may disrupt this balance, leading to microbial diseases. Candida albicans biofilms are formed on indwelling medical devices and have an association with both oral and invasive candidiasis. This study aimed to compare the amount of adherent C. albicans and the biofilm formed on different denture base materials. The adhesion of C. albicans to denture base materials is widely recognized as the main reason for the development of denture stomatitis. Materials and Methods: In total, 56 polymethyl methacrylate (PMMA) acrylic resin disc-shaped samples were divided into four groups as follows: 1) chemically polymerized PMMA, 2) heat-polymerized PMMA, 3) computer-aided design and computer-aided manufacturing (CAD/CAM) PMMA in high polish, and 4) CAD/CAM resins in glazed form. The adherent cells and formation of C. albicans strains (562, 1905, 1912, and 1949) biofilm were measured by the 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) method and use of a microplate reader. Moreover, morphological alterations of C. albicans cells were investigated using scanning electron microscopy (SEM). Results: The biofilm formation was significantly lower on CAD/CAM acrylic resins, compared to conventional denture base materials. The obtained results were confirmed by the SEM images of C. albicans biofilms. CAD/CAM PMMA-based polymers may be preferable to inhibit C. albicans biofilm formation and reduce Candida-associated denture stomatitis in long-term use. Conclusion: Based on the findings, the CAD/CAM technique can be used as an efficient technique for denture fabrication as it inhibits microbial accumulation, and consequently, microbial biofilm.

Protective Effects of the Probiotic Bacterium Streptococcus thermophilus on Candida albicans Morphogenesis and a Murine Model of Oral Candidiasis.

Background: Oral candidiasis is a frequent form of candidiasis, caused by Candida species, in particular, Candida albicans (C. albicans). The transition of C. albicans from yeast to hyphae allows its attachment to epithelial cells, followed by biofilm formation, invasion, and tissue damage. Hence, we investigated the effect of Streptococcus salivarius subspecies thermophilus (S thermophilus) on the growth as well as biofilm and germ-tube formation of C. albicans both in vitro and in vivo in a murine model. Methods: This experimental study was performed in the Department of Medical Mycology and Parasitology, School of Medicine, in collaboration with the Central Research Laboratory and the Comparative Biomedical Center, Shiraz University of Medical Sciences, Shiraz, Iran (2017 to 2018). The inhibitory activity of S. thermophilus against Candida species growth was evaluated using the broth microdilution method, and the inhibition of C. albicans biofilm formation was measured using the XTT assay. The inhibition of C. albicans germ-tube formation by S. thermophilus was evaluated using the plate assay and fluorescence microscopy. The experimental activity of the probiotic bacterium was assessed by culture and histopathological methods in six groups of five mice, comprising those treated with four concentrations of probiotics, fluconazole, and distilled water. The one-way analysis of variance, followed by a Tukey post hoc test, was used and a P value of less than 0.05 was considered significant. Results: S. thermophilus inhibited Candida species growth at concentrations of 16 to 512 µg/mL. This probiotic inhibited the formation of C. albicans biofilms and germ tubes in a dose-dependent manner. S. thermophilus significantly reduced the colony-forming units in the mice receiving 30 mg/mL of this probiotic treatment compared with the control group (P=0.024). The histopathological analysis showed that Candida colonization was diminished in the mice following the administration of the probiotic. Conclusion: Given the inhibitory activity of S. thermophilus against the growth, transition, and biofilm formation of C. albicans, it could be used in the management of oral candidiasis.

Multiplex polymerase chain reaction for detection of bacteremia during dental extraction.

AIM: Incidence of transient bacteremia following dental extractions ranges 30%-70% among adults and 58%-100% in children. This study aims to assess the multiplex polymerase chain reaction (PCR) technique in detection of transient bacteremia during dental extraction. METHODS: Twenty volunteers for dental extraction entered the study. Blood samples were taken at baseline and 30 seconds and 15 minutes after extraction. Five types of bacteria were selected, namely Streptococcus mutans, S. salivarius, S. sanguinis, Enterococcus faecalis and Lactobacillus. Blood samples were evaluated by microbial culture and multiplex PCR. RESULTS: Blood culture showed rates of 0%, 80% and 25% for bacteremia before, during and after dental extraction, respectively. A significant difference was observed between baseline and during extraction. Using PCR, bacteremia was deemed 20%, 100% and 30% before, during and after extraction, respectively, and a significant difference was witnessed between the baseline and during extraction. The highest incidence was at the 30-second mark after extraction, and the most prevalent type of bacteria was S. mutans. CONCLUSIONS: Multiplex PCR can be used to determine bacterial diversity with high accuracy during occurrence of bacteremia. Therefore, in cases where positive blood cultures only indicate the presence of one species, we recommend the use of this method to detect more diverse bacteria types.

The Association of Stone Opacity in Plain Radiography with Percutaneous Nephrolithotomy Outcomes and Complications.

PURPOSE: To investigate the influence of stone opacity in plain radiography on stone free rate and complications ofpercutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: A number of 101 patients who underwent PCNL between July-September 2015 wereprospectively included. Stone opacity was judged on preoperative plain Kidney-Ureter-Bladder X-ray. Stone freerate was evaluated two weeks after the operation by ultrasonography and KUB. RESULTS: There were 61 patients with opaque stones and 40 patients with non-opaque stones. The age, body massindex, preoperative creatinine, history of stone surgery, and stone size was not statistically different betweenpatients with opaque and non-opaque stones. Neither operation duration nor access numbers were statisticallysignificant between opaque and non-opaque stones. The frequency of stone free patients in opaque stones and nonopaquestones were 55/61 (90%) and 30/40 (75%) respectively (P = .04) The magnitude of hemoglobin drop inopaque stones and non-opaque stones were 1.9 ± 1.2 mg/dL versus 2.9 ± 1.7 mg/dL (P = .005). CONCLUSION: The stone free rate is lower and the magnitude of bleeding is higher in PCNL of non-opaque stoneswhen compared to opaque stones if rigid instruments are used for nephroscopy.

Serum inhibin B concentration as a prognostic factor for prediction of sperm retrieval in testis biopsy of patients with azoospermia.

BACKGROUND: This study was conducted to determine if serum inhibin B concentration can predict spermatogenesis in azoospermic infertile men. METHODS: This cross-sectional study included 70 patients with male-factor infertility referred to Alvand and Vali-e-Asr Infertility Centers, Tehran, Iran. All patients had azoospermia. Standard evaluation consisted of history and physical examination with extreme attention to sexual history and testis examination including testis size, consistency, and presence of varicocele. Laboratory evaluation done for all cases consisted of FSH, testosterone, LH, prolactin, and inhibin B. Testis biopsy was performed in all cases with acceptable testis volume and FSH. The mean inhibin B level was compared in groups with positive and negative sperm retrieval. RESULTS: The mean+/-SEM age of 70 azoospermic patients was 32.1+/-6.2 (range: 20 - 50) years. All couples had primary infertility with a mean+/-SEM duration of infertility of 74.3+/-7.7 months. The mean+/-SEM testicular volume was 10.14+/-0.75 mL. The mean+/-SEM FSH and LH levels were 17.55+/-1.68, and 11.33+/-0.99 mIU/mL, respectively. The mean+/-SEM serum prolactin and testosterone levels were 308.77+/-17.35 and 5.45+/-0.91 ng/dL, respectively. The mean+/-SEM serum inhibin B concentration was 138.23+/-28.58 (range: 15 - 1500) pg/mL. Sperm was not retrieved in 82% of the patients; in 13% of the cases, biopsy revealed spermatogenesis. The mean+/-SEM serum FSH level of positive and negative groups was 9.78+/-2.13 and 22.56+/-2.46 mIU/mL, respectively (P<0.05). The mean serum LH, prolactin, and testosterone levels were not statistically different between the two groups. The mean+/-SEM serum inhibin B was 129+/-45.46, and 158.93+/-47.24 pg/mL in positive and negative groups, respectively (P>0.05). CONCLUSION: Inhibin B concentration is not an appropriate predicting factor for testicular spermatogenesis.