Size-dependent molecular interaction of nontraditional 2D antibiotics withStaphylococcus aureus.

The application of nanomaterials for their antibacterial properties is the subject of many studies due to antibiotic resistance of pathogen bacteria and the necessity of omitting them from food and water resources. Graphene oxide (GO) is one of the most popular candidates for antibacterial application. However, the optimum condition for such an effect is not yet clear for practical purposes. To shed light on how GO and bacteria interaction depends on size, a wide range of GO flake sizes from hundreds of µm2going down to nano-scale as low as 10 N m2was produced. In anin-vitrosystematic study to inhibitStaphylococcus aureusgrowth, the correlation between GO flake size, thickness, functional group density, and antibacterial activity was investigated. The GO suspension with the average size of 0.05 µm2, in the order of the size of the bacteria itself, had the best bacteriostatic effect onS. aureuswith the minimum inhibitory concentration value of 8 µg ml-1, well within the acceptable range for practical use. The bacteriostatic effect was measured to be a 76.2% reduction of the colony count over 2 h of incubation and the mechanism of action was the wrapping and isolation of cells from the growth environment. Furthermore,in-vivoanimal studies revealed that 16 µg ml-1of the optimum GO has efficient antibacterial performance against the methicillin-resistant strains of the bacteria with an enhanced wound healing rate and tensiometrial parameters which is important for realized targets.

A New Amphotericin B-loaded Trimethyl Chitosan Nanoparticles as a Drug Delivery System and Antifungal Activity on Candida albicans Biofilm.

Amphotericin B (AmB) is an effective antifungal agent; however, the application of AmB is associated with a number of drawbacks. Application of nanoparticles (NPs) is known to improve the efficiency of drug delivery to the target tissues, compared to the traditional methods. In this study, a novel method of NPs preparation was developed. The trimethyl chitosan (TMC) was synthesized using low molecular weight chitosan and was used for the preparation of TMC-NPs through ionic gelation method. Afterward, AmB-loaded TMC-NPs (TMC-NPs/AmB) were prepared and their drug delivery potential was testes. The TMC-NPs and TMC-NPs/AmB were characterized for their structure, particle size, Zeta potential, polydispersity index, morphology, loading efficiency, loading capacity, in vitro release profile, release kinetic, and entrapped AmB potency. The cytotoxicity and antifungal activity of TMC-NPs/AmB against Candida albicans biofilm were evaluated. The quaternization of TMC was estimated to be 36.4%. The mean particle size of TMC-NPs and TMC NPs/AmB were 210±15 and 365±10 nm, respectively, with a PDI of 0.30 and 0.4, ZP of +34±0.5 and +28±0.5 mV, respectively. Electron microscopy analysis indicated uniform spherical shapes with smooth surfaces. The TMC-NPs/AmB indicated LE of 76% and LC of 74.04 % with a potency of 110%. The release profile of TMC-NPs/AmB was best explained by the Higuchi model. The initial release after 10 h was obtained at 38%, and the rates of release after 36 and 84 h were determined at 67% and 76% respectively, which was significantly different (P<0.05) from previous time points. The minimum inhibitory concentration (MIC) (50%) of NPs/AmB and AmB were 0.65 and 1.75 µg/mL, and the MIC 80% were determined at 1.95 and 7.75 µg/mL, respectively, demonstrating a significant improvement in antifungal activity. The half-maximal inhibitory concentration for TMC-NPs/AmB and AmB were estimated at 86 and 105 µg/mL, respectively, indicating a significant reduction in cytotoxicity and the adverse effect. This study could successfully introduce a practical method to synthesize TMC-NPs. The encapsulation process was efficient and significantly improved the antifungal activity of AmB. The developed method can be applied to improve the feasibility of oral delivery while reducing the adverse effects associated with traditional methods.

Subtilisin Gene Activity in Dermatophytes: A study on the Presence of the Subtilisin Gene in Trichophyton verrucosum and Microsporum gypseum in Clinical and Nonclinical Samples in Tehran, Iran.

The keratinolytic activities of dermatophyte species are accompanied by the secretion of enzymes, such as serine proteases, which are coded by the Subtilisin (SUB) genes. This study aimed to determine the presence of the SUB genes in the clinical and nonclinical samples of Trichophyton verrucosum and Microsporum gypseum. Isolation was carried out by direct and laboratory examination. Following that, for the determination of the presence of the SUB gene, polymerase chain reaction with specific primers was conducted. The frequencies of the SUB gene were observed in almost 66% of the isolates. Statistical analysis showed a significant relationship between the presence of the SUB gene and the samples collected from human, animals, and soil (p ˂0.005). The current investigation has been the first study of the presence/absence of the SUB gene in the clinical and nonclinical isolates of T. verrucosum and M. gypseum in Iran which may be a new step to perform further studies.

Identification of Dairy Fungal Contamination and Reduction of Aflatoxin M1 Amount by Three Acid and Bile Resistant Probiotic Bacteria.

Aflatoxins (AFs) released by fungi are observed in the cow&rsquo;s milk even after pasteurization. Aflatoxin M1 (AFM1) has particularly an incredible clinical significance, as a critical carcinogenic agent for humans. Several strategies have been implemented for lowering the AFM1 amount, such as the employment of probiotics, particularly lactobacilli or lactic acid bacteria (LAB). However, this strategy has not been applied routinely until today. This study aimed to evaluate the effect of three LABs on the reduction of AFM1 in traditional milk and cheese samples. In total, 85 milk (n=45) and cheese (n=40) samples were obtained from the open markets of Shiraz, Iran, from February to June 2018. Additionally, the AFM1 levels were evaluated, compared to those of the National Iranian Standard. The data were then analyzed in SPSS software (version 20) through the Chi-square test. Statistical analysis was performed at a 95% confidence level (p-value of &lt;0.00001). Out of 50 purchased LABs, the efficient antifungal property and resistance to bile salts were observed in five strains. The mean value of these five strains was calculated after adding 5 ppm AFM1, compared to natamycin. The strains with a reduction in AFM1 level were sequenced and registered in the NCBI database.In total, 15 samples with contamination higher than the allowed limit included Penicillium spp, Aspergillus niger, Saccharomyces cerevisia, Saccharomyces paradoxus, and Yarrowia lipolytica.The results also showed reduced AFM1 levels in three LAB-treated strains. Lactobacillus fermentum CECT562 (T), Lactobacillus brevis ATCC14869 (T), and Enterococcus faecium LMG 11423 (T) had this capability to 0.05, 0.03, and 0.03 respectively. The National Iranian Standard should be implemented to have control over traditional dairy products with more care. The three LABs selected in the current study revealed a significant effect on reducing AFM1 levels in traditional milk and cheese.

Systemic infection with Candida albicans in breast tumor bearing mice: Cytokines dysregulation and induction of regulatory T cells.

OBJECTIVE: The effect of candidemia on immunologic parameters in breast tumor bearing patients is not well studied. Here, we hypothesised that candidemia in the tumor background may change the outcome of immunologic parameters and tumor condition. METHOD: Mice were divided into four groups, including normal, tumor, Candida infected (only Candidiasis) and tumor/Candidiasis groups. Tumor changes were recorded daily after tumor transplantation and induction of candidemia. Splenocytes of mice were harvested, cultured, and stimulated with PHA; afterwards, IL-4, IL-10, IFN-γ, TNF-α and TGF-ß cytokines were assessed using ELISA kits. We also evaluated the population of CD4+CD25+Foxp3+ regulatory T cells in the tumor infiltrated and splenocytes. RESULTS: The results showed that infection with C. albicans decreased the IFN-γ/IL-4 ratio in tumor/candidiasis and candidiasis groups versus their non-infected controls. IL-10, TGF-ß and TNF-α levels increased in the candidiasis group. In addition, Candidemia led to an increase in the Treg population in tumor microenvironment and splenocytes of experimental groups compared with non-infected controls. Finally, candidemia increased tumor growth of tumor/Candidiasis group compared with the tumor group. CONCLUSION: It seems that systemic infection with C. albicans could not only induce regulatory T cells but also result in dysregulation of cytokine network and thereby facilitate tumor growth.

Oral health-related quality of life in patients with temporomandibular disorders: A case-control study considering psychological aspects.

OBJECTIVES: This case-control study aimed to compare patients with temporomandibular disorders (TMD) and healthy controls in terms of oral health-related quality of life (OHRQoL) considering Graded Chronic Pain Scale (GCPS) scores, pain duration, psychological impairment and demographic characteristics. METHODS: A total of 75 patients with TMD and 75 healthy controls were recruited. The short version of Oral Health Impact Profile (OHIP-14) was administered for evaluating the OHRQoL. Psychosocial impairments were assessed using the General Health Questionnaire-28 (GHQ-28). The Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) axis I and II were also used for patient diagnosis and collecting GCPS scores, pain duration, age and gender. Independent-sample t tests, Pearson's chi-square tests and multiple logistic and linear regression models were applied for statistical analysis. RESULTS: The mean age of the patients was 34.3±12.4 years. A female-to-male ratio of 6:1 was seen in the TMD group. The prevalence and severity of the OHIP were significantly different between the TMD and control groups (66.7% vs 12.0% and 18.0 vs 9.2, respectively). According to multiple logistic regression for OHIP prevalence and multiple linear regression for OHIP severity in the TMD group, GCPS scores and pain duration, followed by psychological impairment, were the most important predictors of the OHRQoL. CONCLUSION: TMD negatively affected the OHRQoL, particularly in patients with psychological impairments. Meanwhile, age and gender did not seem to have a serious effect. Hence, promoting the quality of life of patients with TMD requires emphasis on chronic pain management and maintaining good mental health.

The Effect of Locally Administered Pamidronate on Autogenous Bone Graft in Maxillofacial Reconstruction: A Randomized Clinical Trial.

BACKGROUND: Although bone grafts are commonly used in reconstructive surgeries, they are sensitive to local perfusion and are thus prone to severe resorption. Biphosphonates can inactivate osteoclasts and can be used to control the undesirable bone resorption. OBJECTIVE: To assess the effect of administration of biphosphonates on bone resorption. METHODS: 20 patients with bony defects who were candidates for free autogenous grafts were randomized into "pamidronate" and "control" groups. Bone segments were soaked in either pamidronate solution or normal saline and were inserted into the area of the surgery. Bone densities were measured post-surgery and in 6-month follow-up. Data were obtained via Digora software and analyzed. RESULTS: The mean±SD bone density in pamidronate group changed from 93.4±14.6 to 93.6±17.5 (p<0.05); in the control group the density decreased from 89.7±13.2 to 78.9±11.4 (p<0.05). The mean difference of bone density in anterior areas of the jaws showed higher DXA in comparison to posterior regions (p=0.002). CONCLUSION: Locally administered pamidronate affects reduction in bone resorption.

The cytokinesis-blocked micronucleus assay: dose-response calibration curve, background frequency in the population and dose estimation.

An in vitro study of the dose responses of human peripheral blood lymphocytes was conducted with the aim of creating calibrated dose-response curves for biodosimetry measuring up to 4 Gy (0.25-4 Gy) of gamma radiation. The cytokinesis-blocked micronucleus (CBMN) assay was employed to obtain the frequencies of micronuclei (MN) per binucleated cell in blood samples from 16 healthy donors (eight males and eight females) in two age ranges of 20-34 and 35-50 years. The data were used to construct the calibration curves for men and women in two age groups, separately. An increase in micronuclei yield with the dose in a linear-quadratic way was observed in all groups. To verify the applicability of the constructed calibration curve, MN yields were measured in peripheral blood lymphocytes of two real overexposed subjects and three irradiated samples with unknown dose, and the results were compared with dose values obtained from measuring dicentric chromosomes. The comparison of the results obtained by the two techniques indicated a good agreement between dose estimates. The average baseline frequency of MN for the 130 healthy non-exposed donors (77 men and 55 women, 20-60 years old divided into four age groups) ranged from 6 to 21 micronuclei per 1000 binucleated cells. Baseline MN frequencies were higher for women and for the older age group. The results presented in this study point out that the CBMN assay is a reliable, easier and valuable alternative method for biological dosimetry.

Identification of Mucorales isolates from soil using morphological and molecular methods.

BACKGROUND AND PURPOSE: Soil is the main habitat of saprophytic and pathogenic fungi. Mucoromycotina constitutes a large group of soil fungi, with certain opportunistic members causing systemic infections in immunocompromised hosts. The majority of human and animal infections are caused by the members of the genera Rhizopus, Mucor, Rhizomucor, Lichtheimia (Absidia), Cunninghamella, and Mortierella. Accordingly, in the present study, we aimed to isolate and identify the main genera of the order Mucorales, using molecular assays and morphological features. MATERIALS AND METHODS: In total, 340 soil samples were collected from seven public parks throughout the city and sidewalk gardens in 14 municipal districts in Isfahan, Iran. All the samples were cultured on the appropriate media, incubated at 27°C for 2- 4 days, and examined daily for visible fungal growth. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was applied and macroscopic, microscopic, and physiological characteristics were assessed to identify fungal colonies. RESULTS: 400 pure colonies, belonging to the orders Mucorales and Mortierellales, including the genera Lichtheimia, Rhizopus, Rhizomucor, Mucor, Cunninghamella, and Mortierella, were identified. The genus Rhizopus (35.5%) was the most frequent isolate, followed by Mucor (32.25%) and Rhizomucor (27.5%). CONCLUSION: The results emphasize the importance of opportunistic fungi in public areas and indicate the risk of exposure for immunocompromised individuals.

Bone Reconstruction following Application of Bone Matrix Gelatin to Alveolar Defects: A Randomized Clinical Trial.

BACKGROUND: Conventional dentoalveolar osseous reconstruction often involves the use of graft materials with or without barrier membranes. OBJECTIVE: To evaluate the efficacy of bone induction by bone matrix gelatin (BMG), delivered on an absorbable collagen sponge (ACS), compared to a placebo (ACS alone) in human alveolar socket defects. METHODS: 20 alveolar sockets from 10 healthy adults were studied. In all cases, both the mandibular premolar area and the contralateral premolar area (as the control site) were involved. In each of the 10 patients, the extraction sites were filled randomly with BMG and ACS. The repair response was examined on day 90. Qualitative histological and quantitative histometric analysis, including the percentage of new-formed bone fill and density were done. RESULTS: Assessment of the alveolar bone indicated that patients treated with BMG had significantly (p<0.05) better bone quality and quantity compared to the controls. In addition, bone density and histology revealed no differences between the newly induced and native bone. CONCLUSION: The data from this single-blind clinical trial demonstrated that the novel combination of BMG had a striking effect on de novo osseous formation for the bone regeneration.

Spreader graft placement: a simplified technique for young surgeons.

The spreader graft is a longitudinal graft placed between the dorsal septum and the upper lateral cartilage in a submucoperichondrial pocket. This graft has functional and aesthetic indications. Although placement and suturing of the spreader graft to the septum is an easy part of rhinoplasty for the experienced surgeon, it can be difficult and time-consuming for young surgeons. Here we suggest a very simple technique for easier placement and suturing of spreader grafts.

Finite element analysis on longitudinal and radial functionally graded femoral prosthesis.

This study focused on developing a 3D finite element model of functionally graded femoral prostheses to decrease stress shielding and to improve total hip replacement performance. The mechanical properties of the modeled functionally graded femoral prostheses were adjusted in the sagittal and transverse planes by changing the volume fraction gradient exponent. Prostheses with material changes in the sagittal and transverse planes were considered longitudinal and radial prostheses, respectively. The effects of cemented and noncemented implantation methods were also considered in this study. Strain energy and von Mises stresses were determined at the femoral proximal metaphysis and interfaces of the implanted femur components, respectively. Results demonstrated that the strain energy increased proportionally with increasing volume fraction gradient exponent, whereas the interface stresses decreased on the prostheses surfaces. A limited increase was also observed at the surfaces of the bone and cement. The periprosthetic femur with a noncemented prosthesis exhibited higher strain energy than with a cemented prosthesis. Radial prostheses implantation displayed more strain energy than longitudinal prostheses implantation in the femoral proximal part. Functionally graded materials also increased strain energy and exhibited promising potentials as substitutes of conventional materials to decrease stress shielding and to enhance total hip replacement lifespan.

Blood pressure, height, weight and body mass index of primary school students in a low socio-economic district in Turkey.

AIM: This study was conducted to evaluate the growth and blood pressure measurements of the students. BACKGROUND: School health services are important to evaluate, protect and to improve the health status of the students. This study was conducted to evaluate the growth and blood pressure measurements of the students who were registered in a primary school with low socio-economic level in Kayseri Province in Türkiye between 1 April 2004 and 30 May 2004. The data were collected using questionnaire and health-screening forms. FINDINGS: It was determined that the average age was 9.77 +/- 2.41 in girls and 10.16 +/- 14.70 in boys. It was observed that the average height was 137.95 +/- 14.70 cm, and the average weight was 33.07 +/- 10.08 kg for all students. The girls between 10 years and 12 years old had a better average body mass index (kg/m(2)) (BMI) compared with boys. Boys between 6 years and 9 years old had a better BMI than the girls. The difference between the groups was considered statistically important (P = 0.006 and P = 0.002, respectively). Furthermore, 4.9% of the students were underweight and 2.2% of the students were obese. It was thought that there was a positive correlation among height, weight, BMI, age and the blood pressure values; and as BMI and age increased, so did the blood pressure value. CONCLUSION: Cooperation and dialogue need to be established among the school directorate, the families and the students to promote and encourage proper growth development and nutrition of the students within the school health services.

Meat balls: a pathognomonic ultrasound and computed tomography finding in mature cystic teratoma.

One of the commonest germ cell tumours are mature cystic ovarian teratomas. Although the imaging features of teratomas are highly variable, the sonographic and CT identification of fatty and calcific components are fairly suggestive. The case presented, however, is of an unusual, yet pathognomonic CT and ultrasound imaging appearance of an ovarian teratoma that was due to floating balls.

Evidence of resilience in families of children with autism.

BACKGROUND: Family resilience is a growing field of inquiry, investigating factors that contribute to a family's becoming stronger in spite of dealing with adversity. Despite the growing interest in studying family resilience, the topic has not been explored in families with children who have disabilities. This report, a part of a larger study--using both quantitative and qualitative methodologies--is an examination of factors of family resilience in the families of children with autism. Evidence of family resilience such as family connectedness and closeness, positive meaning-making of the disability, and spiritual and personal growth were identified and examined in this part of the study. METHOD: The study uses a survey methodology, analysing responses to several rating scales and written responses to three open-ended questions. Survey respondents consisted of 175 parents and other primary caregivers of a child with autism--ages between 2 and 18 years. RESULTS: Results suggest identification of specific resilience processes, such as: making positive meaning of disability, mobilization of resources, and becoming united and closer as a family; finding greater appreciation of life in general, and other people in specific; and gaining spiritual strength. CONCLUSIONS: This study presents evidence that a considerable number of families of children with autism display factors of resilience--reporting having become stronger as a result of disability in the family.