RESUMO
AIMS: The aim of this study was to optimize the potential of Beauveria bassiana through cell electrofusion technique with emphasis on improving its thermotolerance and virulence against western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae) (WFT). METHODS AND RESULTS: Nine B. bassiana isolates were tested against western flower thrips, F. occidentalis (Thysanoptera: Thripidae) (WFT) to estimate their pathogenicity and speed of infection under laboratory conditions. The isolates were also exposed to 25, 36, 38 and 40°C, for 24, 48, 72 and 120 h. Two isolates with the highest virulence against WFT and highest thermotolerance were selected and paired using a cell electrofusion technique to obtain a single strain that was both highly virulent and thermotolerant. To determine the hybrid conidia among the fusion cells, each selected isolate was loaded with a different nuclei-staining fluorescent dye before the fusion process. Hybridized fungal strains were acquired by a series of sequential dilutions and were tested for thermotolerance and virulence against WFT. Those that demonstrated both characteristics (high thermotolerance and virulence) similar to or greater than the parental isolates were considered hybrids. CONCLUSIONS: The results demonstrated that genetic transformation using cell electrofusion can be used to obtain hybrid isolates of fungal pathogens that contain the desired genes from selected isolates. Further DNA-based analysis is required to determine the genetic variation between hybrids and the parental isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to demonstrate genetic transformation in B. bassiana by use of cell electrofusion and it could be developed to create superior hybrid isolates with various desired properties for integrated pest management and industrial uses in the future.
Assuntos
Beauveria/genética , Termotolerância/genética , Animais , Beauveria/patogenicidade , Beauveria/fisiologia , Controle Biológico de Vetores/métodos , Tisanópteros , Transformação Genética , VirulênciaRESUMO
Assuntos
Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Silicose , Tuberculose , Humanos , Tuberculose/epidemiologia , Prevalência , Doenças Pulmonares Intersticiais/epidemiologia , Silicose/epidemiologia , Fibrose Pulmonar Idiopática/epidemiologiaRESUMO
AIM: A unique characteristic of some new bonding systems in operative dentistry is they combine conditioning and priming agents into a single acidic primer solution for simultaneous use on both enamel and dentin. Combining conditioning and priming into a single treatment step results in improvement in both time and cost-effectiveness to the clinician and, indirectly, to the patient. The purpose of this study was to determine the effects of the use of a self-etching primer on the bond strength of orthodontic brackets and on the bracket/adhesive failure mode. METHODS AND MATERIALS: Thirty-six fresh bovine incisors were collected and stored in a solution of 0.1% (weight/volume) thymol. The criteria for tooth selection included intact buccal enamel, no cracks caused by the presence of the extraction forceps, and no defects. The teeth were cleansed and polished with pumice and rubber prophylactic cups for ten seconds. Brackets were bonded to the teeth according to one of three protocols following the manufacturers' instructions--Group 1: Conventional multistep bonding system (control group) (n=12); Group 2: Self-etching primer system (n=12); and Group 3: Acid+self-etching primer system (n=12). Specimens were loaded to failure in a Zwick test machine (Zwick GmbH & Co, Ulm, Germany). Shear bond strengths were measured at a crosshead speed of 5 mm/min. RESULTS: The mean shear bond strength in megapascals (Mpa) (standard deviation) were 11.7 (4.2), 10.5 (4.4), and 10.9 (4.8) for Groups 1, 2, and 3, respectively. The analysis of variance (ANOVA) was used to compare the three groups. The results indicated no significant difference in the bond strength between the three groups (P=0.800). The results of the Chi square test, evaluating the residual adhesives on the enamel surfaces, revealed no significant difference between the three groups (P=0.554). CONCLUSION: Results of the present in vitro study indicate the use of self-etching primers may be an alternative to conventional phosphoric acid pre-treatment in orthodontic bonding.
Assuntos
Colagem Dentária , Braquetes Ortodônticos , Cimentos de Resina , Condicionamento Ácido do Dente/métodos , Análise de Variância , Animais , Bovinos , Distribuição de Qui-Quadrado , Descolagem Dentária , Esmalte Dentário , Análise do Estresse Dentário , Ácidos Fosfóricos , Resistência ao CisalhamentoRESUMO
AIM: The main purpose of this study was to assess the prevalence and distribution of decayed, missing, and filled teeth (DMFT) and enamel hypoplasia in 12-year old students in junior high school in Iran. MATERIALS AND METHODS: This descriptive study was carried out in 2001 on 1,223 12-year old students, which were randomly selected in Yazd and Hadi-Shahr, Iran. A questionnaire was designed to record the status of the teeth along with the occupational and educational levels of parents. Data was analyzed using SPSS software, the Chi-square test, and analysis of variance (ANOVA). RESULTS: The mean DMFT score was 1.8 +/- 1.75 and 28.6% of the students were caries-free. There was no significant relationship between DMFT and the rate of dental caries with parents' education and occupation. The percentage of enamel hypoplasia was 32.7%. No statistically significant relationships were found between hypoplasia and DMFT with regard to gender. The relationship between enamel hypoplasia with DMFT score and dental caries was statistically significant. CONCLUSION: In the present study findings for DMFT scores in 12-year old junior high school children are higher than global standards according to the World Health Organization (WHO) references for the year 2000. There was a strong association between enamel hypoplasia and dental caries, and this subject suggests early diagnosis of enamel defects, health education programs, and suitable treatments should be emphasized in junior high school-aged children.
Assuntos
Cárie Dentária/complicações , Cárie Dentária/epidemiologia , Hipoplasia do Esmalte Dentário/complicações , Hipoplasia do Esmalte Dentário/epidemiologia , Análise de Variância , Distribuição de Qui-Quadrado , Criança , Índice CPO , Escolaridade , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Ocupações , Prevalência , Inquéritos e QuestionáriosRESUMO
Hepatitis B virus (HBV) infection, one of the major health priorities, accounts approximately for 350 million chronic cases and a global total of 33 million people were living with human immunodeficiency virus (HIV) in the world.Co-infection with HIV and the HBV presents a significant challenge to health care providers, with different prevalence rates in different parts of the world. It is important to screen all HIV infected individuals for HBV infection and reverse. Infection with HBV becomes more violent in patients co-infected with human immunodeficiency syndrome. HIV/HBV co-infected individuals are at increased risk of chronic hepatitis, cirrhosis, and hepatocellular carcinoma, and of experiencing HAART toxicity. In this review, the latest statistics on epidemiology of HIV, HBV and their co-infection has been presented along with prominent characteristics of HBV. Transmission routes which are the common between HBV and HIV are described and the most important ones are described according to the regional and age features. Also, there is a series of actions being performed once HBV infections occur to prevent HIV or to diagnose if the HBV-infected individuals are also infected with HIV. As in treatment case, some of the frequent treatment methods including applying interferon and using nucleoside and nucleotide analogues have been discussed. Finally, we would explain the new recommendations for treating patients who were co-infected with HBV and HIV, including staging HBV and HIV treatment, based on the stage of each disease. It also outlines the optimal treatment options, whether the patient is treated for HBV first, HIV first, or HIV and HBV together.