Iron acquisition by Actinobacillus suis: identification and characterization of a single-component haemoglobin receptor and encoding gene

Actinobacillus suis is an important swine pathogen. As with other pathogens, the ability of A. suis to acquire iron within the host is crucial for virulence. Here, we investigated the ability of seven strains of A. suis to acquire iron from haemoglobins. In growth assays, all strains could use porcine, bovine and human haemoglobins as iron sources for growth. Using solid phase binding assays, membranes derived from all strains, grown under iron-restricted conditions, were shown to bind all three haemoglobins. Competition binding assays indicated that these haemoglobins were bound by the same receptor and an affinity procedure allowed the isolation and identification of an iron-repressible, haemoglobin-binding polypeptide (approximately 105 kDa) from all strains. Nucleotide sequence analyses revealed that A. suis possesses a gene (hgbA) that encodes a homologue of the Actinobacillus pleuropneumoniae haemoglobin-binding protein, HgbA. hgbA, encoding a mature protein of 105 kDa, was shown to be preceded by a hugZ homologue; putative promoter sequences and a putative Fur box were located upstream of hugZ and RT-PCR revealed that hugZ and hgbA are co-transcribed and iron-repressible. It is concluded that the acquisition of haemoglobin-bound iron by A. suis involves a single-component receptor that is up-regulated in response to iron restriction.     

Adipose stem cell side population in the mouse

Adipose tissue has become a reliable source of adult stem cells, which appear to possess a yet‐undetermined degree of plasticity. With the difficulties associated with harvesting adult bone marrow stem cells, adipose tissue may represent a valuable and easily acquired source of stem cells. Stem cells have been identified using the DNA binding dye Hoechst 33342 and flow cytometry in various tissues known as the side population (SP). The present study shows, for the first time, the presence of side population stem cells in adult adipose tissues. Flow cytometric identification and isolation of this subpopulation of stem cells revealed that in the mouse there are 2.5% of adipose SP cells within the stromal vascular fraction of adipose tissue. In culture, mouse adipose SP cells showed the capacity to undergo in vitro differentiation into osteogenic, chondrogenic and adipogenic lineages. In NOD/SCID mice, freshly sorted mouse adipose SP cells were able to engraft and assist in wound healing. This animal model study showed that adipose SP cells were able to regenerate epithelial layers and connective tissue with minor scar formation. The ability of this novel cell population within adipose tissue to undergo directional differentiation in vitro and to regenerate skin in vivo has potential impact for uses in surgical dermal applications. Copyright © 2009 John Wiley & Sons, Ltd.     

Non Alcoholic Fatty Liver Disease in Southern Iran: A Population Based Study

Background

Population based studies on prevalence and risk factors of NAFLD in Iranian population are few. The prevalence of NAFLD and non alcoholic steatohepatitis (NASH) in Iranians varies from 2.9% to 7.1% in general population and 55.8% in patients with type 2 diabetes mellitus.

Objectives

To determine the prevalence and determinants of non alcoholic fatty liver disease (NAFLD) in a sample of adult Iranian general population.

Patients and Methods

This was a cross-sectional study being performed in Shiraz, southern Iran during a 10-month period from November 2010 to September 2011 through cluster random sampling of Iranian general population in Shiraz region. All individuals undergone anthropometric, blood pressure measurements, thorough medical history and physical examinations. Laboratory measurements included fasting blood glucose (FBS), lipid profile, complete blood count (CBC) and liver function tests. NAFLD was diagnosed by transabdominal ultrasonography.

Results

819 subjects were included in this study among which were 340 males (41.5%) and 479 females (58.5%) with the mean age of 43.1 ± 14.1 years. NAFLD was diagnosed in 176 (21.5%) subjects. Patients with NAFLD were significantly older (P < 0.001), had higher proportion of male gender (P = 0.004) and had higher BMI (P < 0.001). They also had higher prevalence of hypertension (P < 0.001), high FBS (P < 0.001), high cholesterol (P = 0.026), high triglyceride (P < 0.001) and high waist circumference (P < 0.001). Taking all these together, patients with NAFLD had significantly higher prevalence of metabolic syndrome when compared to healthy subjects (P < 0.001).

Conclusion

The prevalence of NAFLD in this group of Iranian adult general population is 21.5%. NAFLD in Iranian population is associated with male gender, old age, obesity, and features of metabolic syndrome.     

Different polysomnographic patterns in military veterans with obstructive sleep apnea in those with and without post-traumatic stress disorder

Introduction and objectives

Obstructive sleep apnea (OSA) is a prevalent disorder among military veterans. The goal of this study is to compare the polysomnographic patterns of OSA in military veterans who have a history of post-traumatic stress disorder (PTSD) with those of veterans who have not PTSD.

Materials and methods

Seventy-two Iranian military male veterans were classified into two groups: those with PTSD (40 cases) and those without PTSD (32 cases). Each participant was diagnosed with OSA using an overnight polysomnography, during which sleep-related parameters such as sleep efficiency (SE) and apnea-related events were detected. The body mass index (BMI) and Epworth Sleepiness Scale (ESS) were also assessed.

Results

For the PTSD group, mean age was 53.83?±?7.3 years, elapsed time since they participated in war was 28.3?±?3.4 years, apnea-hypopnea index (AHI) was 41.2?±?27, SE was 77.7?±?17.55%, ESS was 7.93?±?2.04, BMI was 26.5?±?5.7, and PLM index was 12.725?±?8.64. The above respective parameters for the non-PTSD group were 51.33?±?5.9 years, 28.3?±?3.4 years, 30.33?±?14.7, 82.4?±?15.65%, 10.08?±?3.02, 31.5?±?6.7, and 8.8?±?3.54. The relationships of AHI with ESS and BMI were not significant in PTSD group.

Conclusion

OSA in military veterans suffering from PTSD presents more often with insomnia than obesity or increased daytime sleepiness. These findings are different from those typically seen in non-PTSD veterans with OSA.

     

Determinants of Iranian dentists’ behaviour regarding infection control

Aim: To evaluate the determinants of Iranian dentists’ behaviour regarding infection control (IC). Design: A cross-sectional questionnaire survey. Setting: Iranian general dental practitioners (GDP) participating in a national dental congress. Methods: The GDPs filled in a self-administered questionnaire containing questions regarding their attitudes towards and their behaviour on several aspects of IC. Background factors included GDP’s year of birth, gender, and work-related factors. Statistical evaluation employed the Chi-square test, Cronbach alpha, and regression analysis. Results: In total, 479 GDPs returned the questionnaire. Their mean age was 38.6 years (SD = 9.4) and 53% were men. The vast majority of the GDPs had positive attitudes towards the inquired after IC criteria with no statistical difference based on the GDP’s background characteristics. Of all respondents, >70% reported that they inform the laboratory about the infection status of the sent items, disinfect impressions before sending to the laboratory, and wash patients’ mouths before working with high-speed or ultrasonic devices. Adherence to all the studied IC criteria was reported by 10% of the respondents; more frequently by younger GDPs and those with fewer experience years (P < 0.05). Conclusion: Greater emphasis on infection control programmes in dentists’ education is called for especially in continuing education.Key words: Infection control, general dental practice, Iran     

Pregabalin antinociception and its interaction with tramadol in acute model of pain

BackgroundThe aim of present study was to investigate the antinociceptive effect of pregabalin and tramadol either alone and or in combination on acute model of pain.MethodsThe antinociceptive effect of intraperitoneal administration of pregabalin (1 to 400 mg/kg) and tramadol (10 to 80 mg/kg) or combination of them were measured after 30 and 60 min on hot-plate in terms of maximum possible effect (%MPE) in mice.ResultsAntinociceptive effect rose significantly for both pregabalin at doses 200 and 400 mg/kg and tramadol from 20 to 80 mg/kg in dose dependent manner. From linear equation the doses that increased antinociceptive effect by 50% (ED50) were 69 ± 8.2 mg/kg for tramadol and 246 ± 24 mg/kg for pregabalin. Unlike pregabalin, %MPE₃₀ (at 30^th min) of tramadol was significantly higher than its %MPE₆₀. The interaction after co-administration of non analgesic dose of 10 mg/kg of pregabalin with low analgesic dose of 30 mg/kg of tramadol resulted super-additive and %MPE30 and %MPE₆₀ were increased compared to each drug alone. In all other combination groups, the interaction were sub-additive particularly when non analgesic doses of each drug (10 mg/kg) were co-administrated and %MPE was decreased significantly compared to that of each drug alone.ConclusionPregabalin revealed a comparative antinociceptive effect as similar to tramadol in acute model of pain, but interaction between these two drugs depends highly on their proportion in the combination. The analgesia may increase but adverse effects such as seizurogenic effect of tramadol can be reduced in clinical setting if right proportion is used. More studies are required to understand the mechanisms and clinical implication of such combinations.     

Variation in omeprazole pharmacokinetics in a random Iranian population: a pilot study

Omeprazole is metabolized in the liver mainly by the polymorphic CYP2C19 enzyme. Considerable ethnic differences have been reported in the pharmacokinetics of omeprazole. The present study was conducted to evaluate the pharmacokinetic parameters of omeprazole after a single oral administration to a random Iranian population. Thirty healthy male subjects, aged 24–31 years, weighing 60–98 kg completed the study. Plasma concentrations of omeprazole were measured over a 12 h period after administration of a single oral dose of 20 mg omeprazole. The pharmacokinetic parameters were calculated from the plasma concentration–time profiles. Liquid chromatography coupled to tandem mass spectrometry (LC‐MS/MS) was used to quantify 5‐hydroxyomeprazole. The mean area under the concentration–time curve (AUC) from time zero to infinity (AUC_∞) values of omeprazole and the corresponding coefficient of variation (CV%) was 987.3 ng h/ml (65%). In general, most subjects showed a normal distribution. Only one subject showed a very high AUC compared with the corresponding mean AUC level. This subject had the highest half‐life and the lowest rate of elimination. The omeprazole metabolic ratio for this subject was 2.9, while for the others it was in the range 0.12–0.56. These results are consistent with previous literature that showed the existence of interindividual variability in omeprazole pharmacokinetics, even within a single ethnic group. Differences in the pharmacokinetics could be due to differences in the genetic make‐up of subjects as found in their omeprazole metabolic ratios. Copyright © 2012 John Wiley & Sons, Ltd.     

Epidemiological characteristics of fatal traffic accidents in Fars province,Iran: a community-based survey

Objectives

To determine the epidemiological characteristics of fatal traffic accidents in Fars province, Iran.

Study design

This cross-sectional study included 3642 traffic accident deaths in Fars province, Iran between November 2009 and November 2011. The data source was the Fars Forensic Medicine Registry, which covers the entire province. According to Iranian law, all deaths resulting from injuries or accidents must be investigated to determine the exact cause of death by autopsy. All such deaths are referred to forensic medicine centres in each city, and all data are sent to the main centre in Shiraz, the capital city of Fars province.

Results

Males accounted for 78.3% of the decedents (sex ratio of almost 3.6:1), and the mean ± standard deviation age of all decedents was 32.2 ± 20.3 years. Autopsy reports indicated that head trauma was the most common cause of death. Most collisions were vehicle–vehicle crashes (52.3%), with cars and motorcycles being the most prevalent modes of transport (39.6% and 24.6%, respectively). Fatal accidents were most common during the summer. Most fatal injuries (61.4%) occurred on outer-city roads and 27.4% occurred on inner-city roads. Significant associations were found between decedent's status (car driver, motorcycle driver or passenger, pedestrian or passenger) and interval between injury and death, light conditions at the scene of the accident, place of death, site of injury and cause of death.

Conclusion

Although the clinical management of trauma patients has improved in Iran, coordination between trauma system organizations is required to decrease the burden of injuries.