Evaluation of in vivo Lethality and in vitro Cytotoxic Effect of Odontobuthus bidentatus Scorpion Venom.

The results of numerous studies have revealed that some deadly scorpion venoms are composed of various bioactive molecules that have significant cytotoxic effects on cancer cells. In this study, the in vivo lethality and cytotoxic effect of Odontobuthus bidentatus venom were evaluated in different cancer cell lines. Through MTT assay, the cytotoxic effects of O. bidentatus scorpion venom were analyzed on the MCF-7, A549, AGS, HepG2, and Ht-29 cancer cell lines and Hu02 normal cells. To this end, six venom fractions were obtained through a Sephadex G-50 column, and the cytotoxic effects of isolated fractions were evaluated on A549 lung cancer cells. The median lethal dose of O. bidentatus scorpion venom was determined at 0.73 mg/kg by intravenous administration of different venom doses in male BALB/c mice according to the Spearman-Karber method. The O. bidentatus scorpion whole venom had a significant cytotoxic effect on MCF-7, A549, and AGS cells. The treatment of A549 cells with various concentrations of fraction F1 showed that this fraction significantly induced growth inhibitory effect on the cells in a dose-dependent manner, compared to untreated cells.

Analysing the HERV-K env, np9, rec and gag expression in cervical tissues.

Cervical cancer is considered to be the fourth common cancer. It is assumed that numerous risk factors, especially infectious ones, can have a detrimental effect on cervical cancer. In this study, we evaluated the expression of Herv-K env, np9, rec and gag in cervical tissues. After RNA extraction and cDNA sensitizing of 12 cervical cancer tissues and CIN3, 51 CIN1,2 and 18 normal ones, Herv-K env, np9, rec and gag were assessed using quantitative real-time PCR analysis. There was a decrease in the level of HERV-K env expression in cervical cancer and CIN 1-3 in compression with normal tissues. Cervical cancer and CIN3 indicated the most increase in expression. Meanwhile, we observed an increase in gag and rec expression in CIN 1,2; although cervical cancer and CIN 3 had a decrease in rec and gag expression, we did not report any changes in np expression. In conclusion, given the relationship between HERV-associated genes and cervical cancer, our study suggests that these genes can be useful for cancer diagnosis. However, further investigations are needed to provide a better perspective about the effectiveness of these genes in the diagnostic strategies of gastrointestinal cancer. These results are just an observation that could open a wider investigation to test the correlation between the expression of these genes and cervical cancer.

Molecular Identification of Mycoplasma agalactiae in Iran Based on P30 Gene.

Mycoplasma agalactiae (M. agalactiae) is known as the main etiological agent of contagious agalactia (CA). The CA is a disease affecting dairy sheep and goats, the main characteristics of which include keratoconjunctivitis, arthritis, and mastitis. This pathogen results in milk production reduction and suppression, thereby leading to serious economic loss. In the present study, 125 sheep and goat samples were collected from 15 provinces of Iran. Cultural and molecular methods were used for sample characterization. After extracting genomic DNAs using the phenol/chloroform method, the PCR technique was employed to detect Mycoplasma genus in 163bp fragment of 16S rRNA gene (M-PCR) and M. agalactiae in 800bp fragment of conserve and specific P30 lipoprotein gene (P30-PCR) in cultural and clinical samples. Finally, to validate the experimental approach, a 375 bp amplicon of P80 lipoprotein was amplified using the MA-PCR. Out of 125 samples under investigation, 43 cases were positive, and Mycoplasma colonies were observed in the pleuropneumonia-like organisms agar culture. Based on the results of the M-PCR method, 61 specimens (out of 125 samples) were scored positive for Mycoplasma presence. Furthermore, 20 samples were positive according to the P30-PCR data. It should be mentioned that the MA-PCR was performed based on the P80 gene on 125 total samples to furtherverify the results for M.agalactiae detection. Based on the obtained data, P30 and P80 genes were presented and amplified in all Iranian M. agalactiae isolates (n=20). Our results indicated that the P30 gene was conserved and specific to all Iranian M. agalactiae isolates and this new P30-PCR method (as an MA-PCR technique) might be useful in the detection of this pathogen.

Rifampin resistance among individuals with extrapulmonary tuberculosis: 4 years of experience from a reference laboratory.

Information is limited about the drug resistance patterns in extrapulmonary tuberculosis (EPTB) in Iran. This study aimed to determine the prevalence of EPTB and to investigate the drug-resistance pattern in Mycobacterium tuberculosis strains collected from extrapulmonary samples at the Tehran regional TB reference laboratory. Extrapulmonary specimens from individuals with suspected TB referred to the TB reference laboratories in five cities of Iran were collected. Both standard conventional methods (culture and direct smear microscopy) and Xpert MTB/RIF assay were used for the identification of mycobacteria. Drug susceptibility testing was done using Xpert MTB/RIF. The proportion method on Lowenstein-Jensen medium was performed for confirmation. Between 2016 and 2020, a total of 12 050 clinical specimens from individuals with suspected TB were collected, of which 10 380 (86%) were pulmonary specimens and 1670 (14%) were extrapulmonary. Of the extrapulmonary specimens, 85 (5.0%) were positive for M. tuberculosis, and the remaining 1585 (95.0%) samples were negative by standard methods. Of 85 M. tuberculosis isolates, drug susceptibility testing was performed for 32 isolates, of which 1 (3.1%, 95% CI 0.0%-9.4%) was rifampin resistant and 31 (96.9%, 95% CI 90.1%-100%) were pan-susceptible. The rifampin-resistant isolate was also resistant to isoniazid, so was assigned as a multidrug-resistant TB. Our study indicated the frequency of drug-resistance among EPTB in Iran. Establishing rapid diagnostic methods for detection of drug-resistance in EPTB, performing drug susceptibility testing for all EPTB cases to provide effective treatment, and continuous monitoring of drug resistance, are suggested for prevention and control of drug resistance in EPTB in Iran.

Genotyping and drug susceptibility testing of Mycobacterium tuberculosis in Iran: a multi-centre study.

Tuberculosis (TB) is a deadly infection and caused 1.4 million deaths in 2018. Assessing the geographic distribution of major lineages of Mycobacterium tuberculosis can contribute greatly to TB control. Mycobacterial interspersed repetitive unit variable number tandem repeat (MIRU-VNTR) typing is commonly used to differentiate various lineages of M. tuberculosis. A total of 2747 clinical specimens were collected consecutively from October 2018 through June 2019. Clinical isolates were identified as M. tuberculosis using standard biochemical tests. The standard 15-locus MIRU-VNTR typing was used for the genotyping of clinical isolates. Drug susceptibility testing was performed using the conventional proportion method. From the collected specimens, 100 were culture positive for M. tuberculosis. Using MIRU-VNTR, 99 different patterns were detected among the 100 isolates. They were distributed in one cluster comprising two strains and 98 unique patterns. Most of our isolates were similar to New-1 and Delhi/CAS strains. Of the M. tuberculosis isolates, 83 (83.0%) were pan-susceptible and 17 (17.0%) were resistant to at least one drug. Our study showed that MIRU-VNTR is a useful method for studying the genetic diversity of M. tuberculosis isolates in different regional settings and will help the health authorities to construct a preventive programme for TB.

Epidemiology of herpes simplex and varicella zoster virus in cerebrospinal fluid of patients suffering from meningitis in Iran.

From the early 18th century that "meningitis" outbreak was firstly recorded in Geneva, it is one of the alarming health problems worldwide. Different infectious risk factors may contribute to the progression of meningitis. Herpes simplex virus (HSV) and Varicella-zoster virus (VZV) are just some noticeable risk factors among many involved in the progression of this disease. In this study, 415 meningitis suspected patients were recruited with some symptoms, such as fever, headache, nausea or vomiting, seizure, rash, dizziness from four different hospitals of Iran and molecular examinations of samples were performed by using specific primers of HSV½ and VZV via real-time PCR. Out of 415 included patient 41 (9.8 %) were VZV and six (1.4 %) cases were HSV ½ positive. Fever was the most frequent symptom by 315 (76 %) of patients with median temperature of 38 °C in all included patients. The median WBS counts of CSF in VZV positive, HSV½ positive, and all included cases were 1567 × 106 /L, 1257 × 106 /L, and 766 × 106 /L (range 0-21200), respectively. In conclusion, as the rate of VZV infection was high among children patients and it was associated with the absence of vaccination program for chickenpox in Iran, we suggested that VZV is one of the plausible hallmarks in meningitis.

Ultrafast electron dynamics in monolayer MoS2 interacting with optical pulse influenced by exchange field and waveform.

In this paper, we investigate the effect of waveform and carrier-envelope phase on the electron dynamics in monolayer MoS2 interacting with an ultrashort (few-femtosecond) optical pulse in the presence of magnetic exchange field. The waveform of the zero area pulse is characterized by Hermite-Gaussian polynomials associated with time-dependent and carrier-envelope phases. Because the duration of optical pulse is less than the characteristic electron scattering time (10-100 fs), the electron dynamics is coherent, and can be described by the time-dependent Schrödinger equation. We show, that the electron transition from valence band to conduction band is a deeply irreversible dynamics, which implies quantum electron dynamics is highly nonadiabatic. We study the effect of carrier-envelope phase and exchange field on the conduction band population for two types of waveform. Electron distribution in reciprocal space gives asymmetric hot spots in different K and K' valleys after the pulse ends (valley polarization effect), which is found to be more sensitive to carrier-envelope phase. The predicted effect provides new opportunities for the improvement of information processing in the petahertz domain and optoelectronics applications.

High-resolution melt curve analysis for rapid detection of rifampicin resistance in Mycobacterium tuberculosis: a single-centre study in Iran.

This study aimed to compare the diagnostic accuracy of high-resolution melting (HRM) analysis in comparison with Xpert MTB/RIF as well as conventional drug susceptibility testing (DST) for the detection of rifampicin (RIF) resistance in Mycobacterium tuberculosis in Iran. A comparative cross-sectional study was carried out from April 2017 to September 2018. A total of 80 culture-positive clinical samples selected during the study period were analysed for detection of RIF-resistant TB by conventional DST, Xpert MTB/RIF, and sequencing. Sensitivity and specificity of the HRM calculated according to DST was our reference standard test in this study. The overall sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of HRM assay were found to be 100%, 89.33%, 38.46%, and 100% respectively. The analysis demonstrated that the diagnostic accuracy of HRM tests is insufficient to replace Xpert MTB/RIF and conventional DST. HRM tests have the advantage of time to result and may be used in combination with culture. Further work to improve molecular tests would benefit from standardized reference standards and the methodology.

Mass-like band-gap creation in superconducting topological insulator due to mixed singlet and triplet states.

We investigate proximity-induced mixed spin-singlet and spin-triplet superconducting state on the surface states of a topological insulator. Such hybrid structure features fundamentally distinct electron-hole excitations and resulting effective superconducting subgap. Studying the particle-hole and time-reversal symmetry properties of the mixed state Dirac-Bogoliubov-de Gennes effective Hamiltonian gives rise to manifesting possible topological phase exchange of surface states, since the mixed-spin channels leads to appearance of a band gap on the surface states. This can be verified by evaluating topological invariant winding number for chiral eigenstates, via the introducing a chiral symmetry operator. We interestingly find the role of mixed-spin superconducting state as creating a mass-like gap in topological insulator by means of appearing new mixed-spin channels [Formula: see text] and [Formula: see text]. The interplay between superconducting spin-singlet and triplet correlations actually results in gaped surface states, where the size of gap can be controlled by tuning the relative s- and p -waves pairing potentials. We show that the system is in different topology classes by means of using chiral or no-chiral spin-triplet symmetry. In addition, the resulting effective superconductor subgap manipulated at the Fermi surface presents a complicated dependency on mixed-spin channels. Furthermore, we investigate the resulting subgap tunneling conductance in N/S, and also Josephson current in S/I/S junctions to unveil the influence of effective symmetry of mixed superconducting gap. The results can pave the way to realize the effective superconducting gap in noncentrosymmetric superconductors with mixed-spin state.

Characterization and full genome sequencing of a velogenic Newcastle disease virus (NDV) strain Ck/IR/Beh/2011 belonging to subgenotype VII(L).

Avian avulavirus 1, better known as Newcastle disease virus (NDV), causes substantial loss to the poultry industry in many developing countries. In this study we have characterized and fully sequenced the genome of a velogenic NDV strain named Beh (Ck/IR/Beh/2011) that has been used in our lab for a number of challenge and immunological studies over the last few years. This strain was isolated from poultry in the city of Behshahr, Mazandaran Province, Iran after an outbreak reported in the region in 2011. The intracerebral pathogenicity index (ICPI) was 1.8 in one-day-old chicks, characteristic of a velogenic NDV strain. Later, the virus was purified using a sucrose gradient centrifugation and used for next-generation sequencing (NGS). The results showed that the genome length was 15192 bp, similar to those of class II velogenic strains. In addition, the phylogenetic analysis based on the complete F gene showed that the NDV strain Beh has an F protein cleavage site 112RRQKR↓ F117 and belongs to the newly identified subgenotype VII(L). Based on the biological and genetic characterization, NDV strain Beh is now the best documented reference isolate representing the novel subgenotype VII(L) in Iran. Keywords: NDV; NGS; velogenic strain, subgenotype VII(L); phylogenetic analysis.

Comparison of the first Iranian native Ornithobacterium rhinotracheale vaccine with conventional vaccine: A challenge study.

BACKGROUND AND AIM: The best strategy to prevent or control an Ornithobacterium rhinotracheale (ORT) infection is vaccination. The present study aimed to compare the efficacy of the first Iranian inactivated ORT vaccine (Razi, Iran), which had been prepared from a native strain, with the Nobilis ORT Inac (Intervet, The Netherlands) through a challenge trial. MATERIALS AND METHODS: Seventy-two 1-day-old specific pathogen-free White Leghorn chickens were used in this study. The birds were divided randomly into four groups. Following the vaccination and challenge of the birds, the efficacy of the Razi and the Intervet ORT vaccines was evaluated by serological, bacteriological, and molecular methods. RESULTS: The antibody titer in vaccinated groups was determined to be significantly higher than unvaccinated birds. In addition, the difference in postmortem lesion scores between the vaccinated and unvaccinated birds was significant. The differences in the means of the antibody titers and postmortem lesion scores in birds that were vaccinated by the Razi and Intervet ORT vaccines were not significant. CONCLUSION: Considering the results of this study, it can be concluded that the Iranian native ORT vaccine was comparable to the Intervet vaccine. The Razi ORT vaccine has effectively decreased the duration of the ORT infection and can effectively protect the chickens against an ORT infection.

Bradykinin-Potentiating Factors of Venom from Iranian Medically Important Scorpions.

The venom of animals, including snakes, scorpions, and spiders is a complex combination of proteins, peptides, and other biomolecules as well as some minerals. Among the biomolecules of some animal’s venom, small peptides that lack disulfide bands known as Non-Disulfide Bridge Peptides (NDBPs) potentiate the bradykinin by preventing the conversion of angiotensin 1 to angiotensin 2 using the mechanism of inhibiting the Angiotensin-Converting Enzyme activity and finally reducing the blood pressure in the victims. This feature of the NDBPs of animal’s venom is suggested as the potential of biological drugs. This study aimed to isolate venom components of three species of Iranian medically important scorpions and study the bradykinin potentiating effect of them. The scorpion specimens were collected from the venomous animals and antivenom production department of Razi Vaccine and Serum Research Institute, Karaj, Iran. Moreover, venom extraction was performed by electrical shock (5 volts). The obtained liquid venom of three species specimens was frozen and lyophilized immediately and then preserved in a cool and dried place. The isolation of the venom components for each scorpion was carried out using high-performance liquid chromatography. The obtained ranges of venom fractions (zones) were tested on isolated tissues of guinea-pig ileum and rat uterus using organ bath instrumentation in several replicates. The bioassays resulted in the peptides, including Z1 and Z2 regions in the venom fractionsof the Hottentotta saulcyi, Z2 in Odontobuthus doriae, as well as Z2 and Z3 in Mesobuthus eupeus demonstrated bradykinin potentiating effect. It is concluded that Bradykinin Potentiating Factors were traceable in the venom of all three scorpion species. Therefore, these venoms have the therapeutic potential to exploit biological-based drugs.

Mycobacterium simiae pulmonary disease in Iran: systematic review and meta-analysis.

Mycobacterium simiae is one of the most common nontuberculous mycobacteria (NTM) microorganisms causing lung disease in many countries in the world. A reliable estimate of the extent of M. simiae pulmonary disease has not been well investigated in Iran. We systematically searched multiple databases to identify relative studies. Studies were excluded if they did not use the American Thoracic Society (ATS) and Infectious Diseases Society of America (IDSA) diagnostic criteria for NTM diseases. Data were extracted independently and in duplicate. We assessed pooled estimate by using a random model effect, and sources of heterogeneity were assessed by using Cochran's Q and the I 2 statistic. The potential for publication bias was explored by using Begg's and Egger's tests. All analyses were conducted with Stata 14.0 (StataCorp, College Station, TX, USA). Of 172 articles identified, seven met the inclusion criteria. Of 355 patients who were culture positive for NTM, 82 had M. simiae pulmonary disease according to the ATS/IDSA diagnostic criteria. The pooled frequency of M. simiae pulmonary disease among patients with NTM was 25.0% (95% confidence interval, 16.8-33.2). No evidence of publication bias was observed among the included studies (p >0.05 for Begg's and Egger's tests). Clinical isolates of M. simiae are increasingly being recognized as a cause of pulmonary disease in Iran and need further attention by health authorities.

Prospective predictors of exacerbation status in severe asthma over a 3-year follow-up.

BACKGROUND: A predisposition to exacerbations is being recognized as a distinct phenotype with "previous exacerbations" representing the strongest clinical factor associated with future exacerbation. Thus, to identify additional novel biomarkers associated with asthma exacerbations, "past exacerbation status" must be included as a confounding factor. OBJECTIVE: This study aimed to characterize the clinical and biomarker features associated with asthma exacerbations in severe asthma. METHODS: We evaluated clinical parameters from 105 severe asthmatics yearly for 3 years, as well as their exacerbation status. We classified the subjects into 3 groups: (i) consistent non-exacerbators (CNE, subjects who did not experience any exacerbation over the 3-year period); (ii) consistent frequent exacerbators (CFE, subjects with frequent exacerbation, defined as those who had 2 or more exacerbations within 1 year, throughout the 3-year period); and (iii) intermittent exacerbators (IE). We conducted multivariate analysis for comparisons among the groups for multiple factors, including several Th2-related biomarkers, in addition to the "past exacerbation status." RESULTS: Thirty-nine subjects were classified as CNE, 15 as CFE, and 51 as IE. Frequent exacerbations in the previous year predicted exacerbations for the following year (P < .001). Among the several Th2-related biomarkers, only FeNO was associated with exacerbation status. When we analysed the data after the second visit, the impact of FeNO on predicting future exacerbation remained significant, even after considering the exacerbation status during the first year (P < .05). CONCLUSIONS AND CLINICAL RELEVANCE: Measurement of FeNO has a significant potential to predict future asthma exacerbation, which is independent of the "past exacerbation history."

The Characteristics of an Ovine Lymphoid Cell-Line sensitive to Vaccinal Infectious Bursal Disease Virus Strain.

Infectious bursal disease (IBD), also known as Gumboro disease, is a globally well-known disease with a significant socio-economic effect. For control of IBD, several commercial egg- and cell-based vaccines are prepared. The cell-based IBD vaccines are significantly cost-effective; however, it is essential to confirm their safety and efficacy. The main cell line used to product the cell-based IBD vaccines, is a primary chicken embryo fibroblast (CEF). Nevertheless, manipulation of CEF is extremely challenging and time-consuming. This study aimed to characterize a sensitive suspension cell culture from ovine lymphoid, according to WHO technical report series; No. 978, Annex III. This authentication covered the growth curves, sensitivity, stability, karyotyping and identifying the adventitious agents. This cell line passed all defined tests and was considered as a suitable one for IBD vaccine preparation in a large scale.

Molecular analysis of the bacille Calmette-Guérin vaccine strain currently being used in Iran.

BACKGROUND: In developing countries, tuberculosis (TB) infection control remains a challenge. The bacille Calmette-Guérin (BCG) vaccine is the only effective vaccine available for TB control. Iran uses a local BCG vaccine strain with an unknown substrain. OBJECTIVE: To investigate the molecular characteristics of the current BCG strain being used in Iran using comparative genomics of the evolutionarily late strains, including BCG vaccines Pasteur, BCG-Danish, BCG-Glaxo, BCG-Prague, BCG-Frappier, BCG-Connaught and BCG-Moreau. METHODS: A total of 67 different vials of BCG vaccine were cultured. DNA was extracted using the modified cetrimonium bromide (CTAB) method, and multiplex polymerase chain reaction (PCR) was performed to determine four target genomic regions of difference (RD) 1, RD8, RD16 and SenX3-RegX3, and to see whether RD2 and RD14 were present. RESULTS: Our results showed that all studied batches were Mycobacterium bovis; molecular analysis revealed that the Iranian vaccine strains possess RD8, RD16 and SenX3-RegX3 regions but not RD1, RD2 and RD14. All of the vaccine batches analysed were compatible with BCG-Pasteur 1173p2, the original strain. CONCLUSION: All of the BCG strains studied were recognised as the BCG-Pasteur 1173p2 strain. No genetic diversity among stocks and ready-for-use vaccine vials were detected.

Detection of Ambler class A, B and D ß-lactamases among Pseudomonas aeruginosa and Acinetobacter baumannii clinical isolates from burn patients.

In this study, we evaluated the existence of classes A, B and D ß-lactamases among Pseudomonas aeruginosa (P.aeruginosa) and Acinetobacter baumannii (A.baumannii) strains isolated from burn patients in Tehran during the years 2012 and 2013. From these strains, the frequency of MBL (metallo-beta-lactamase) and ESBL (extended-spectrum beta-lactamase) producers were evaluated using CDDT (Combined Disk Diffusion Tests). The prevalence of some related genes, including blaIMP, blaVIM, blaSPM, blaKPC, blaGIM, blaDIM, blaBIC, blaOXA-48, blaCTX-M-15 and blaNDM genes, was evaluated using PCR and sequencing methods. Of the 75 non-fermenter isolates, 47 P.aeruginosa and 28 A.baumannii were isolated and identified. A high rate of resistance to common antibiotics was detected among A.baumannii isolates in particular, showing 100% resistance to 9 tested antibiotics. CDDT showed that 21 (28%) and 25 (34.25%) of the non-fermenter isolates were ESBL and MBL producers respectively. The prevalence of blaCTX-M-15 and blaIMP genes among the 75 non-fermenter isolates was 7 (9.3%) and 1 (1.3%), respectively. Fortunately, no other genes were detected in either of the non-fermenters. The mortality rate due to MBL-producing isolates was 5 (20%). This study showed specific resistance genes exist among some MBL and ESBL gram-negative non-fermenters which were isolated from burn patients in Tehran.

Dans cette étude, nous avons évalué l'existence des classes A, B et D de ß-lactamases chez les souches de Pseudomonas aeruginosa (P.aeruginosa) et Acinetobacter baumannii (A.baumannii) isolées des patients brûlés à Téhéran pendant les années 2012 et 2013. La fréquence des producteurs du MBL (métallo-bêta-lactamase) et du BLSE (bêta-lactamase à spectre étendu) a été évaluée par les tests de diffusion sur les disques combinées, et la prévalence de certains gènes liés (y compris les gènes blaIMP, blaVIM, blaSPM, blaKPC, blaGIM, blaDIM, blaBIC, blaOXA-48, blaCTX-M-15 et blaNDM) a été vérifiée avec des tests pour réaction en chaine à la polymérase et les méthodes de séquençage. Un totale de 75 isolats non-fermenteurs ont été isolés et identifiés : 47 étaient P.aeruginosa et 28 étaient A.baumannii. Un taux élevé de résistance aux antibiotiques communs a été détecté parmi les isolats d'A.baumannii en particulier, avec une résistance de 100% aux 9 antibiotiques testés. Les tests de diffusion des disques combinés a montré que 21 (28%) et 25 (34,25 %) des isolats non-fermenteur étaient producteurs du BLSE et du MBL respectivement. La prévalence des gènes blaCTX-M-15 et blaIMP parmi les 75 isolats non-fermenteurs était 7 (9,3%) et 1 (1,3%), respectivement. Heureusement, d'autres gènes n'ont pas été détectés. Le taux de mortalité due aux isolats producteurs des MBL était 5 (20%). Cette étude a montré que des gènes avec des résistances spécifiques existent parmi certains non-fermenteurs MBL et BLSE Gram-négatifs qui ont été isolés des patients brûlés à Téhéran.

Emergence of Pseudomonas aeruginosa cross-infection in children with cystic fibrosis attending an Iranian referral pediatric center.

BACKGROUND AND OBJECTIVES: This study was carried out with the objective of determining the genomic variability of P. aeruginosa strains isolated from patients suffering from cystic fibrosis or from environmental cultures collected from different locations in the unit they admitted. MATERIALS AND METHODS: A total of 57 clinical and environmental P. aeruginosa isolates were genotyped by enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR), and antimicrobial susceptibility testing was performed using the Clinical and Laboratory Standards Institute method. RESULTS: One predominant ERIC profile (type A) was identified in 46 strains (81% of all typed isolates) which was responsible for thirty-nine of 44 clinical isolates (89%) and 7 of 13 environmental isolates (54%). All clinical isolates were susceptible to piperacillin-tazobactam, ceftazidime and cefepime followed by ticarcillin, aztreonam, amikacin and tobramycin (96.5%). CONCLUSIONS: In our country CF patients are not segregated from other patients, and transmission of bacteria between these patients and other patients might occur in the wards via personal contact or contaminated environment. Future evaluation for policy of patient segregation is necessary and the elimination of contaminated sources and control of environmental spread and recurrent contamination risk is needed.

Enhancement and control of acoustic cavitation yield by low-level dual frequency sonication: a subharmonic analysis.

Evaluation of inertial cavitation is a significant problem where this mechanism of action is responsible for therapeutic applications such as drug delivery. It has shown that using multiple frequencies one is able to enhance and control induced cavitation. In this study, we used different sonication frequencies as 28 kHz, 130 kHz, 1 MHz, 3 MHz and their dual combinations to enhance acoustic cavitation. At each frequency, two different intensities were used and the subharmonic amplitude of each frequency in combinations was measured. It was observed that in combinations which include 28 kHz, the cavitation activity is enhanced. The 28 kHz subharmonic amplitude was used to compare these protocols in their ability to enhance cavitation. Besides, the area of cavitation damage was determined using an aluminum foil. Our results showed that the inertial cavitation activity increased at higher intensities and there is a significant correlation between the subharmonic amplitude and sonication intensity at each frequency (R>0.90). In addition, simultaneous combined dual-frequency orthogonal sonication at 28 kHz with other frequencies used can significantly increase the inertial cavitation activity as compared to the algebraic sum of the individual ultrasound irradiations in 28 kHz subharmonic frequency. The 28 kHz subharmonic amplitude for 28 kHz (0.04 W/cm(2)) and 3 MHz (2 and 1 W/cm(2)) combined dual frequency were about 4.6 and 1.5 times higher than that obtained from the algebraic sum of 28 kHz and 3 MHz irradiation, respectively. Also the 28 kHz subharmonic amplitude for combination of 28 kHz (0.04 W/cm(2)) and 1 MHz (2 and 1 W/cm(2)) were about 2.4 and 1.6 times higher than that obtained with their algebraic sum. Among different combinations, the continuous mode for two ultrasound sources of 28 kHz (0.04 W/cm(2)) and 3 MHz (2 W/cm(2)) is more effective than other combinations (p-value<0.05). The results of effective irradiation area showed no damaged aluminum foil in MHz sonication alone. However, there is significant difference between the effective irradiation area of combined dual frequency 28 kHz and 3 MHz with other irradiation modes (p-value<0.05) and it is limited locally.