Objective: To explore the relationship between extracellular enzymes activity and virulence of Candida glabrata clinical isolates based on the infection model of Galleria mellonella larvae. Methods: Using experimental research methods, 71 strains of non-repetitive Candida glabrata were collected from Qinghai Provincial People's Hospital from June 2021 to January 2022. Bovine serum protein agar medium, egg yolk agar medium, sheep blood agar medium, Tween-80 agar medium and triglyceride agar medium were used to detect the aspartyl protease activity, phospholipase activity, hemolysis activity, esterase activity and lipase activity of Candida glabrata. Median lethal concentration (LC₅₀) was calculated by using 1.25×10⁸ CFU/ml,2.50×10⁸ CFU/ml,3.75×10⁸ CFU/ml,5.00×10⁸ CFU/ml suspension of Candida glabrata ATCC2001 to infect Galleria mellonella larvae. Histopathological and etiological analysis was performed to determine whether the infection model was successfully established. The clinical isolates of Candida glabrata were configured to infect Galleria mellonella larvae with LC₅₀ concentration to detect the pathogenicity of Galleria mellonella larvae.Spearman test or Pearson test were used to analyze the correlation between the extracellular enzyme activity of Candida glabrata clinical isolates and the pathogenicity of Galleria mellonella larvae. Results: 71 strains of Candida glabrata isolated clinically were detected to have low hemolytic activity after 2 days of culture. Aspartyl protease was detected after 4 days of culture, among which 7 strains (9.86%), 19 strains (26.76%) and 45 strains (63.38%) showed low, medium and high aspartyl protease activity. After 7 days of culture, 71 strains did not detect phospholipase, esterase and lipase activities. Candida glabrata on Galleria mellonella larvae of LC₅₀=2.5×10⁸ CFU/ml Fungal spore were found in the intestinal tissue pathological section of Galleria mellonella larvae in the experimental group, and Candida glabrata was identified by the microbial Mass Spectrometry after culture, while no fungi were found in the pathological section and culture of the control group. Spearman test shows that, there was a linear positive correlation between aspartyl protease activity and the survival rate of Galleria mellonella larvae (r = 0.73, P<0.01), the difference was statistically significant.Pearson test shows that, there was no significant linear relationship between hemolytic activity and survival rate of Galleria mellonella larvae (r = 0.16, P = 0.34), the difference was not statistically significant. Conclusion: The clinical isolates of Candida glabrata in this study had aspartyl protease activity and low hemolytic activity, but no phospholipase, esterase and lipase activity. The activity of aspartyl aspartyl protease of Candida glabrata was positively correlated with the pathogenicity of Galleria mellonella larvae.
Animals ; Sheep ; Larva/microbiology* ; Virulence ; Candida glabrata ; Agar ; Moths/microbiology* ; Esterases ; Aspartic Acid Proteases ; Lipase

Glioblastoma is the most common primary cranial malignancy, and chemotherapy remains an important tool for its treatment. Sanggenon C(San C), a class of natural flavonoids extracted from Morus plants, is a potential antitumor herbal monomer. In this study, the effect of San C on the growth and proliferation of glioblastoma cells was examined by methyl thiazolyl tetrazolium(MTT) assay and 5-bromodeoxyuridinc(BrdU) labeling assay. The effect of San C on the tumor cell cycle was examined by flow cytometry, and the effect of San C on clone formation and self-renewal ability of tumor cells was examined by soft agar assay. Western blot and bioinformatics analysis were used to investigate the mechanism of the antitumor activity of San C. In the presence of San C, the MTT assay showed that San C significantly inhibited the growth and proliferation of tumor cells in a dose and time-dependent manner. BrdU labeling assay showed that San C significantly attenuated the DNA replication activity in the nucleus of tumor cells. Flow cytometry confirmed that San C blocked the cell cycle of tumor cells in G_0/G_1 phase. The soft agar clone formation assay revealed that San C significantly attenuated the clone formation and self-renewal ability of tumor cells. The gene set enrichment analysis(GSEA) implied that San C inhibited the tumor cell division cycle by affecting the myelocytomatosis viral oncogene(MYC) signaling pathway. Western blot assay revealed that San C inhibited the expression of cyclin through the regulation of the MYC signaling pathway by lysine demethylase 4B(KDM4B), which ultimately inhibited the growth and proliferation of glioblastoma cells and self-renewal. In conclusion, San C exhibits the potential antitumor activity by targeting the KDM4B-MYC axis to inhibit glioblastoma cell growth, proliferation, and self-renewal.
Humans ; Glioblastoma/genetics* ; Bromodeoxyuridine/therapeutic use* ; Signal Transduction ; Proto-Oncogene Proteins c-myc/metabolism* ; Agar ; Cell Proliferation ; Cell Line, Tumor ; Apoptosis ; Jumonji Domain-Containing Histone Demethylases/metabolism*

OBJECTIVE: Agar dilution method (ADM) was used as the golden standard to evaluate the consistency of Epsilometer test (E-test) in detecting the sensitivity of Helicobacter pylori (H. pylori) to metronidazole. METHODS: From August 2018 to July 2020, patients with H. pylori infection treated for the first time in Peking University Third Hospital for gastroscopy due to dyspepsia were included in this study. Gastric mucosas were taken from the patients with H. pylori infection. H. pylori culture was performed. Both the ADM and E-test were applied to the antibiotic susceptibility of H. pylori to metro-nidazole, and the consistency and correlation between the two methods were validated. RESULTS: In the study, 105 clinical isolates of H. pylori were successfully cultured, and the minimum inhibitory concentration ≥ 8 mg/L was defined as drug resistance. Both ADM and the E-test showed high resistance rates to metronidazole, 64.8% and 62.9%, respectively. Among them, 66 drug-resistant strains were detected by ADM and E-test, and 37 were sensitive strains, so the consistency rate was 98.1%. Two strains were evaluated as drug resistance by ADM, but sensitive by the E-test, with a very major error rate of 1.9%. There was zero strain sensitive according to ADM but assessed as resistant by the E-test, so the major error rate was 0%. Taking ADM as the gold standard, the sensitivity of E-test in the detection of metronidazole susceptibility was 97.1% (95%CI: 0.888-0.995), and the specificity was 100% (95%CI: 0.883-1.000). Cohen's kappa analysis showed substantial agreement, and kappa coefficient was 0.959 (95%CI: 0.902-1.016, P < 0.001). Spearmans correlation analysis confirmed this correlation was significant (r=0.807, P < 0.001). The consistency evaluation of Bland-Altman method indicated that it was good, and there was no measured value outside the consistency interval. In this study, cost analysis, including materials and labor, showed a 32.2% higher cost per analyte for ADM as compared with the E-test (356.6 yuan vs. 269.8 yuan). CONCLUSION The susceptibility test of H. pylori to metronidazole by E-test presents better agreement with ADM. Because it is less expensive, less labor intensive, and more rapid, it is an easy and reliable method for H. pylori susceptibility testing.
Humans ; Metronidazole/therapeutic use* ; Helicobacter pylori ; Agar/therapeutic use* ; Disk Diffusion Antimicrobial Tests ; Microbial Sensitivity Tests ; Helicobacter Infections/drug therapy* ; Anti-Bacterial Agents/therapeutic use*

PURPOSE: The purpose of this study was to evaluate the antimicrobial effects of a toothbrush with light-emitting diodes (LEDs) on periodontitis-associated dental biofilm attached to a zirconia surface by static and dynamic methods. MATERIALS AND METHODS: Zirconia disks (12 mm diameter, 2.5 mm thickness) were inserted into a 24-well plate (static method) or inside a Center for Disease Control and Prevention (CDC) biofilm reactor (dynamic method) to form dental biofilms using Streptococcus gordonii and Fusobacterium nucleatum. The disks with biofilm were subdivided into five treatment groups-control, commercial photodynamic therapy (PDT), toothbrush alone (B), brush with LED (BL), and brush with LED+erythrosine (BLE). After treatment, the disks were agitated to detach the bacteria, and the resulting solutions were spread directly on selective agar. The number of viable bacteria and percentage of bacterial reduction were determined from colony counts. Scanning electron microscopy (SEM) was performed to visualize alterations in bacterial morphology. RESULTS: No significant difference in biofilm formation was observed between dynamic and static methods. A significant difference was observed in the number of viable bacteria between the control and all experimental groups (P < 0.05). The percentage of bacterial reduction in the BLE group was significantly higher than in the other treated groups (P < 0.05). SEM revealed damaged bacterial cell walls in the PDT, BL, and BLE groups, but intact cell walls in the control and B groups. CONCLUSION: The findings suggest that an LED toothbrush with erythrosine is more effective than other treatments in reducing the viability of periodontitis-associated bacteria attached to zirconia in vitro.
Agar ; Bacteria ; Biofilms ; Cell Wall ; Centers for Disease Control and Prevention (U.S.) ; Dihydroergotamine ; Erythrosine ; Fusobacterium nucleatum ; In Vitro Techniques ; Microscopy, Electron, Scanning ; Photochemotherapy ; Streptococcus gordonii ; Toothbrushing

OBJECTIVES: The purpose of this study is to determine methods of dental caries prevention by investigating the use of compounds of Diospyros kaki (D. kaki) peel, Momordica charantia (M. charantia), and Canavalia gladiata (C. gladiata) extracts to limit the cariogenic traits of Streptococcus mutans (S. mutans), such as their ability to proliferate and adhere to the tooth surface. METHODS: Broth microdilution and the agar spreading assay were used to determine the antimicrobial effect and minimum inhibitory concentration (MIC) of S. mutans extracts. In order to identify the adhesive ability of S. mutans at varying concentrations, culture plates were first stained with 1 ml of 0.01% crystal violet for 15 minutes at room temperature, and then eluted with 1 ml of EtOH:Acetone (8:2) solution for 15 minutes in a 37℃ incubator. Eluted solutions were then evaluated by use of a spectrophotometer at 575 nm. RESULTS: Experiments were conducted in order to investigate the effectiveness of D. kaki peel, M. charantia, and C. gladiata extracts on limiting the proliferation of S. mutans. The MIC was measured as an indication of whether the antibacterial activity of D. kaki peel, M. charantia, and C. gladiata extracts had a significant bacteriostatic effect on S. mutans. M. charantia extract was effective for growth inhibition on S. mutans at a minimum concentration of 0.25%. From the adhesion ability assay, M. charantia extract had an anti-adhesive effect. CONCLUSIONS: These results indicate that M. charantia extract demonstrates antibacterial activity and has an anti-adhesive effect on S. mutans. Due to these properties, M. charantia extract may be used to prevent dental caries.
Adhesives ; Agar ; Canavalia ; Dental Caries ; Diospyros ; Gentian Violet ; Incubators ; Microbial Sensitivity Tests ; Momordica charantia ; Momordica ; Streptococcus mutans ; Streptococcus ; Thiram ; Tooth

PURPOSE: The purpose of this study was to compare the diagnostic yield of five systematic randomized protocols using 12–20 biopsy cores with variably-sized phantoms. METHODS: A total of 100 prostate phantom models were produced by casting liquid devil's tongue jelly using silicone molds. Sets of 20 phantoms were created with the following volumes: 20 mL, 40 mL, 60 mL, 80 mL, and 100 mL. Three focal lesions were created by injecting 0.5 mL of warm agar solution stained with red, blue, and green ink into each phantom model. The focal lesions were verified by ultrasonography. The systematic randomized biopsy protocols consisted of 12, 14, 16, 18, and 20 biopsy cores. The diagnostic yield of the multiple systematic biopsy protocols was compared. RESULTS: The overall detection rates of each model set were 93.3% for 20 mL, 88.3% for 40 mL, 71.7% for 60 mL, 43.3% for 80 mL, and 30.0% for 100 mL. Statistically significant differences in the detection rate were found between 40 mL and 60 mL and between 60 mL and 80 mL. No statistically significant increase in the detection rate was observed within a given volume set even when the number of core biopsies increased from 12 to 20. CONCLUSION: The diagnostic yield of systematic randomized biopsies is inversely proportional to the phantom volume.
Agar ; Amorphophallus ; Biopsy* ; Fungi ; Ink ; Prostate* ; Silicon ; Silicones ; Tongue* ; Ultrasonography

Iran bears a remarkable variety of reptiles. One of the lizard families occurring in Iran is the Family Agamidae which is widely are distributed throughout the old world. The large-scaled rock agamid, Laudakia nupta, is one of the well-known agamid. There are few reports of cloacal microbial on reptiles hence their function in cloacae remains unknown. Laudakia nupta usually live in rural and urban areas and close vicinity to man, they are likely to play an important role in the spread of disease that may be caused by these microorganisms and their transmission to man. Therefore, the aim of this study was to identify the bacterial flora colonizing the cloacal region of Laudakia nupta using molecular studies. The cloacal fluids were directly placed on nutrient agar (NA) plates and incubated at 25 ± 2 ℃ for 48 h. The resulting bacterial colonies were transferred to fresh nutrient agar (NA) plates for molecular studies. Twelve isolates were obtained from 17 specimens of Laudakia nupta. All bacteria isolates were identified as Bacillus subtillis (5), Bacillus cereus (4), Bacillus sp. (1), Pseudomonas putida (1), and Pseudomonas sp. (1) based on partial sequences of the 16 s rRNA gene. This is the first comprehensive report of bacteria spp. associated with cloaca of Laudakia nupta using molecular studies. In this research, we found that Laudakia nupta can be a carrier of bacteria which can transfer microorganisms to hosts.
Agar ; Bacillus ; Bacillus cereus ; Bacteria ; Cloaca ; Colon ; Genes, rRNA ; Humans ; Iran ; Lizards ; Pseudomonas ; Pseudomonas putida ; Reptiles

Brevibacterium spp. are gram-positive rods that are considered to be strictly nonpathogenic, and a very few cases of their infection in humans have been reported. In this study, we report a case of otitis caused by Brevibacterium otitidis. A 53-year-old woman, who visited the hospital, complained of symptoms, such as otorrhea from both ears, ear fullness, tinnitus, and hearing impairment, for several months. Ear discharge was cultured on blood agar for pathogen identification. Bacteria from the isolated colony were initially identified as Actinomyces odontolyticus by VITEK 2 (bioMerieux, France), whereas VITEK® MS (bioMerieux, France) identified them as Brevibacterium luteolum. Subsequently, bacteria from the isolated colony were confirmed as B. otitidis by 16S rRNA sequencing. Antimicrobial susceptibility testing confirmed their sensitivity to vancomycin and linezolid and resistance to clindamycin and penicillin. To our knowledge, this is the first reported case of otitis caused by B. otitidis in Korea.
Actinomyces ; Agar ; Bacteria ; Brevibacterium ; Clindamycin ; Ear ; Female ; Gram-Positive Rods ; Hearing Loss ; Humans ; Korea ; Linezolid ; Middle Aged ; Otitis ; Penicillins ; RNA, Ribosomal, 16S ; Tinnitus ; Vancomycin

Catabacter hongkongensis is an anaerobic gram-positive coccobacillus that was first isolated in Hong Kong. It is infectious and causes high mortality in patients with rare but underlying diseases. Alistipes indistinctus is an anaerobic gram-negative coccobacillus. This bacterium is a common member of the human intestinal microbiota. We report a case of C. hongkongensis and A. indistinctus isolated from blood cultures of a patient with acute appendicitis. A 35-year-old female patient with no specific medical history was admitted to the hospital due to abdominal pain, vomiting, nausea, and diarrhea experienced on the day before admission. On admission, laboratory tests revealed leukocytosis, neutropenia, and elevated C–reactive protein and procalcitonin levels. Following an abdominal computed tomography showing acute appendicitis with suspected perforation, emergency surgery was performed. Growth was observed in two anaerobic blood culture bottles after four days. After further culturing of the bacteria on Brucella Blood Agar, two types of bacteria were obtained. The two bacterial isolates, one gram-positive and one gram-negative, were unable to be identified using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Thus, 16S rRNA gene sequence analysis was performed, resulting in identification of the bacteria as C. hongkongensis and A. indistinctus. The patient was administered antibiotics and discharged two days after surgery. Although MALDI-TOF MS enables fast and accurate identification of bacteria, C. hongkongensis and A. indistinctus were not listed in the spectral library, and 16S rRNA gene sequence analysis was useful for identifying the two bacteria.
Abdominal Pain ; Adult ; Agar ; Anti-Bacterial Agents ; Appendicitis ; Bacteria ; Brucella ; Diarrhea ; Emergencies ; Female ; Gastrointestinal Microbiome ; Genes, rRNA ; Hong Kong ; Humans ; Leukocytosis ; Mass Spectrometry ; Mortality ; Nausea ; Neutropenia ; Sequence Analysis ; Vomiting

Chryseobacterium hominis is non-fermenting Gram-negative rod that was first identified as a novel species in 2007. Here, we report the first clinical case of C. hominis bacteremia, which was confirmed by MALDI-TOF MS and 16S rRNA gene sequencing. A 16-year-old boy diagnosed with acute lymphoblastic leukemia was hospitalized for three months. Two sets of blood culture test through a peripherally inserted central catheter (PICC), which was inserted a month ago, was performed when his white blood cell count declined and he had a high fever. Colonies of medium sizes that looked round, mucoid, sticky, and grayish on blood and chocolate agar plates were observed. Identification of bacteria using the VITEK MALDI-TOF MS system (BioMérieux, France) was not successful and the VITEK 2 system (BioMérieux, USA) indicated Sphingomonas paucimobilis, with a questionable level of confidence (92%). However, Microflex LT Biotyper (Bruker Daltonics, Germany) showed C. homins (log score: 1.81) and sequence of 16S rRNA showed a 100% identity with C. hominis. Piperacillin-tazobactam was administered since the isolate was susceptible to piperacillin-tazobactam but C. hominis showed growth in the next four follow-up culture of blood drawn through PICC. The fever subsided only after PICC was changed. The clinical prognosis and antimicrobial susceptibility test of C. hominis should be further studied.
Adolescent ; Agar ; Bacteremia ; Bacteria ; Cacao ; Catheters ; Chryseobacterium ; Fever ; Follow-Up Studies ; Genes, rRNA ; Humans ; Leukocyte Count ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Prognosis ; Sphingomonas