This paper introduces the Blinder-Oaxaca decomposition method to be applied in explaining inequality in health outcome across any two groups. In order to understand every aspect of the inequality, ...multiple regression model can be used in a way to decompose the inequality into contributing factors. The method can therefore be indicated to what extent of the difference in mean predicted outcome between two groups is due to differences in the levels of observable characteristics (acceptable and fair). Assuming the identical characteristics in the two groups, the remaining inequality can be due to differential effects of the characteristics, maybe discrimination, and unobserved factors that not included in the model. Thus, using the decomposition methods can identify the contribution of each particular factor in moderating the current inequality. Accordingly, more detailed information can be provided for policy-makers, especially concerning modifiable factors. The method is theoretically described in detail and schematically presented. In the following, some criticisms of the model are reviewed, and several statistical commands are represented for performing the method, as well. Furthermore, the application of it in the health inequality with an applied example is presented.
Studies show that Epstein-Barr virus (EBV) infection can play a role in malignancy and increase the risk of gastric cancer (GC). The objective of this research was to pinpoint genes whose expression ...may be influenced by EBV and play a role in the development of GC.
Candidate genes potentially susceptible to expression modulation in the presence of EBV were identified through the analysis of GSE185627 and GSE51575 datasets. The association of candidate genes with GC and the survival rate of patients was investigated based on the cancer genome atlas (TCGA) data. Also, pathways related to candidate genes were examined through the MsigDB database. The PPI network was used to identify Hub genes. To corroborate the obtained results, we utilized the RT-qPCR method, employing GC samples from both EBV + and EBV-cases, as well as adjacent normal samples.
Our results showed that genes upregulated by the EBV in the GC cell line, as well as in EBV + samples, are significantly linked to pathways involving the immune response, inflammation, and the P53 pathway. Conversely, genes downregulated by EBV are closely linked to pathways involving cell proliferation and mTORC1. Examining the candidate genes revealed that a considerable portion of genes susceptible to downregulation under the influence of EBV exhibit oncogenic roles based on TCGA data. Moreover, some of these genes are associated with an unfavorable prognosis. Protein-protein interaction network analysis of candidate genes highlighted IFI44L and OAS2 as potential hub genes in the EBV-GC axis. Our RT-qPCR results further validated these findings, demonstrating that the expression levels of IFI44L and OAS2 were higher in EBV + samples compared to both healthy and EBV-samples.
Our study underscores the capacity of EBV to exert regulatory control over genes associated with GC malignancy. In addition to its inflammatory effects, EBV elicits transcriptomic changes that appear to attenuate the progression of GC.
Although MOOCs platforms offer a unique way to provide information for a large cohort of participants, only a small percentage of participants complete MOOCs. The high number of dropouts in MOOCs is ...a key challenge, and the literature suggests that it can be affected by participants' motivation. However, it is not known how and to what extent motivation influences participants’ dropout in MOOCs. There is a need to provide an overview of the role of motivation in MOOCs’ retention. In this study, we aimed to identify motivational factors and theories that affect participants’ retention in MOOCs and explain how does motivation supports participants to complete MOOCs. To do so, a systematic review was conducted using specific inclusion and exclusion criteria and a set of relevant keywords and databases which resulted in 50 relevant publications. Our analysis led us to identify six main motivational factors that influence participants’ MOOCs completion including academic, social, course, personal, professional, and technological motives. These factors were divided into two main categories including need-based motivation and interest-based motivation. The results showed that academic motives play the most important role in participants’ MOOCs retention compared to the other factors. It was also found that self-determination theory was used as the most dominant theory to support participants’ motivation for MOOCs completion. In addition, the results revealed that the motivational factors not only impacts participants’ MOOCs retention directly, but also this impact is mediated by participant satisfaction, self-regulation, attitude toward using MOOCs, performance, engagement, and level of participation. Based on the results, further implications for practice and future research are provided.
Salmonellosis, a zoonotic disease, is one of the leading causes of foodborne illness worldwide. It is responsible for most infections caused by consumption of contaminated food. In recent years, a ...significant increase in the resistance of these bacteria to common antibiotics has been observed, posing a serious threat to global public health. The aim of this study was to investigate the prevalence of virulent antibiotic-resistant Salmonella spp. strains in Iranian poultry markets. A total of 440 chicken meat samples were randomly selected from meat supply and distribution facilities in Shahrekord and tested for bacteriological contamination. After culturing and isolating the strains, identification was performed using the classical bacteriological method and PCR. To determine antibiotic resistance, a disc diffusion test was performed according to the recommendations of the French Society of Microbiology. PCR was used to detect resistance and virulence genes. Only 9% of the samples were positive for Salmonella. These were Salmonella typhimurium isolates. All Salmonella typhimurium serotypes tested positive for the rfbJ, fljB, invA and fliC genes. Resistance to TET, cotrimoxazole, NA, NIT, piperacillin/tazobactam and other antibiotics was found in 26 (72.2%), 24 (66.7%), 22 (61.1%) and 21 (58.3%) isolates, respectively. The sul1, sul2 and sul3 genes were present in 20, 12 and 4 of 24 cotrimoxazole-resistant bacteria, respectively. Chloramphenicol resistance was found in six isolates, but more isolates tested positive for the floR and cat two genes. In contrast, 2 (33%) of the cat three genes, 3 (50%) of the cmlA genes and 2 (34%) of the cmlB genes were all positive. The results of this investigation showed that Salmonella typhimurium is the most common serotype of the bacterium. This means that most of the antibiotics commonly used in the livestock and poultry industries are ineffective against most Salmonella isolates, which is important for public health.
The production of biofilms by S. aureus contributes significantly to treatment failures. The present study aims to establish the relationship between biofilm formation and antibiotic resistance and ...adhesion genes in Staphylococcus aureus strains isolated from raw cow milk in Shahrekord, Iran. A total of 90 samples of raw cow’s milk were collected. Presumptive S. aureus strains were obtained using Baird-Parker plates after enrichment in tryptone soy broth, and final colonies were selected from brain heart infusion. Additional tests such as coagulase were done, and the identification was confirmed by the detection of the aroA gene. Biofilm producing strains were screened using a spectrophotometry method applied to microplates. Crystal violet staining was used to quantify the formation of biofilm. An antibiotic susceptibility test was performed using the Kirby–Bauer disc diffusion method. PCR was used to detect several biofilm and antibiotics resistance related genes. The chi-square test and Fisher’s exact test were used to establish a statistically significant relationship between biofilm reaction and antibiotic resistance (p value <0.05). Results show a moderate (38.88%) recovery rate of S. aureus in milk and 65.71% of the isolates were strong biofilm producers. Antibiotic susceptibility tests show an alarming rate of resistance to beta-lactam antibiotics, especially penicillin (100%), ampicillin (91.42%), and oxacillin (71.42%). This finding correlates with antibiotic resistance gene detection, in which the gene blaZ was most found (71.42%), followed by mecA and Aac-D (42.85%). Detection of biofilm-related genes shows that all the genes targeted were found among S. aureus isolates. Statistical tests show a significant correlation between biofilm production and antibiotic resistance in S. aureus. This study revealed that there is a significant correlation between biofilm production and antibiotic resistance in S. aureus isolated from raw milk. These results highlight the need for regular surveillance of the occurrence of S. aureus strains in milk and milk products in Iran.
Even though
(
) is a serious pathogen, its origin is unknown. Poultry (chicken, turkey, quail, goose, and ostrich) is consumed as a regular protein source by many people across the world; therefore, ...sanitary ways of delivering poultry for food are important for global health. As a result, the distribution of the virulence genes
,
,
,
, and
in
isolates in poultry meat, as well as their antibacterial resistance, was investigated. A Wilkins Chalgren anaerobic bacterial medium was used to cultivate 320 samples of raw poultry meat. Disk diffusion and multiplex-PCR were used to investigate both antimicrobial resistance and genotyping patterns.
was found in 20 of 320 (6.25 %) raw chicken meat samples. The highest incidence of
was found in chicken raw meat (15%), whereas no isolate was recovered from goose or quail raw meat (0.00%). Resistance to ampicillin (85%), tetracycline (85%), and amoxicillin (75%) were the most commonly detected in the tested
isolates. The percentage of
isolates with a multiple antibiotic resistance (MAR) index value of more than 0.2 was 17/20 (85%). The most prevalent genotypes detected were
(75%),
(75%),
(70%) and
(65%), and
(60%). The most typically detected genotype patterns were
(45 %),
(45 %), and
(30%).
,
+, and
- genotypes were found in 40%, 30%, and 30% of the population, respectively. In summary, fresh poultry meat was polluted by
, with the
,
, and
genotypes being more prevalent. The simultaneous occurrence of
,
,
,
, and
genotypes in antibiotic-resistant
bacteria raises a serious public health concern regarding the consumption of raw poultry. Future research should evaluate antimicrobial resistance among
isolates in Iran.
► The lead and cadmium concentration in sheep’s milk was higher than the other milks. ► This study showed the cadmium concentration in the samples was less than 500ng/ml. ► The results showed that ...lead contents in 2.9% of samples was higher than 20ng/ml. ► The results concluded that lead contents of milk in Iran might be hazardous to human.
In total, 137 goat, cow, sheep, and buffalo milk samples were collected in different regions of Iran and analysed to determine concentrations of lead and cadmium by a graphite furnace atomic absorption spectrometric method. The mean recovery of the analytical method was 96.3% and 104% for cadmium and lead, respectively. The mean lead and cadmium contents obtained from 137 samples were 1.93±1.48 (range: 0.18–6.11ng/ml) and 9.51±4.93ng/ml (range: 1.84ng/ml–30.50ng/ml), respectively. Lead concentration in 8.1% of sheep and 1.9% of cow milk samples was higher than the newly established Codex standard. The mean concentrations of cadmium and lead in animals aged ⩽3years (n=80; 1.40±1.05ng/ml and 7.91±3.60ng/ml, respectively) were lower than in animals aged >3years (n=58; 2.69±1.67ng/ml and 11.8±5.71ng/ml, respectively).
According to the presence of the weak, diabetic and immunosuppressive patients in hospitals, hospital foods should have a high quality and safety. Cooking a lot of foods higher than daily ...requirement, storage of cooked foods in an inappropriate condition and presence of nurses and servants in distribution of food to patients are the main reasons caused contamination of hospital foods. Shiga toxigenic
is one of the common cause of food poisoning in hospitals. The present research was carried out to study the distribution of virulence factors, O-serogroups and antibiotic resistance properties in STEC strains recovered from Iranian hospital food samples.
Five-hundred and eighty raw and cooked food samples were collected and immediately transferred to the laboratory.
-positive strains were subjected to PCR and disk diffusion method.
Thirty-nine out of 580 (6.72%) hospital food samples were contaminated with
. Raw (20%) and cooked meat (6%) were the most commonly contaminated samples. Raw samples had the higher prevalence of
(
<0.01). Samples which were collected in the summer season had the highest prevalence of bacteria (64.10%). Significant difference was seen between the prevalence of EHEC and AEEC subtypes (
<0.01). The most commonly detected virulence factors in both EHEC and AEEC subtypes were stx
and
. The most commonly detected serogroups were O26 (43.75%) and O157 (25%) and there were no positive results for O103, O145, O91, O113 and O128 serogroups.
(
)-
(100%),
(100%) and
(62.50%) were the most commonly detected antibiotic resistance genes. STEC strains harbored the highest levels of resistance against ampicillin (93.75%), gentamycin (93.75%), tetracycline (87.50%) and ciprofloxacin (81.25%). All of the STEC strains were resistant to at least 3 antibiotics, while the prevalence of resistance against more than 12 antibiotics were 12.50%.
High presence of O157 serogroups, EHEC strains and animal-based antibiotics in cooked foods showed insufficiency of cooking time and temperature in the kitchens of hospitals. Judicious prescription of antibiotics and attentions to the principles of food safety can reduce the risk of resistant and virulent strains of STEC in hospital foods.
Pseudomonas aeruginosa (P. aeruginosa) is a pathogenic bacterium and one of the seafood's most common spoilage microorganisms. In this study, 470 fish samples collected randomly were evaluated for ...the presence of P. aeruginosa, antibiotic resistance, and frequency of virulence factors. Isolation of P. aeruginosa from fish samples was performed on cetrimide agar after an initial enrichment. Representative colonies were selected, and biochemical tests were conducted. An antibiotic resistance test was performed using the disk diffusion method. DNA was extracted, and antibiotic resistance genes, as well as virulence genes, were detected using PCR. Fresh fish showed the highest prevalence of P. aeruginosa (5%). No positive samples contaminated with P. aeruginosa were isolated from frozen fish samples. From smoked, salted, and dried fish, two samples (2.85–4%) were contaminated with P. aeruginosa. The antibiotic resistance against meropenem, imipenem, carbapenem, erythromycin, gentamicin, chloramphenicol, and enrofloxacin was 0%. The lowest antibiotic resistance pattern was observed in fresh fish, and the highest was observed in smoked, salted, and dried fish. Respectively, blaTEM, blaCTX-M, and blaSHV were the most abundant genes encoding antibiotic resistance. The most virulence genes were algD, algU, lasB, toxA, exoS, exoT, and apr. This study suggests that raw seafood could be a source of antibiotic-resistant P. aeruginosa and helps to spread resistance genes through the food chain. It seems that cross-contamination in the fishing, transportation, and supply of seafood can cause increased contamination with Pseudomonas aeruginosa in these products. Therefore, the hygienic principles can effectively reduce contamination by P. aeruginosa. Also, the prophylactic use of antibiotics in these products should be controlled.
Spices and herbs are potential vectors for virulent and pathogenic micro-organisms, which cause illness in consumers, contribute to spoilage, and reduce the durability of foodstuffs. The present ...study aims to provide relevant data about virulence and antibiotic resistance of Bacillus cereus isolated from various spices. A total of 200 samples of 8 types of spices (black pepper, chilli, white pepper, cumin, cinnamon, turmeric, curry powder, and sumac) were collected from various markets, retail shops, and sucuk production premises located in the Isfahan province of Iran. Presumptive B. cereus strains were obtained using Bacara Agar plates after enrichment in saline peptone water and final colonies were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Enterotoxin (HBL) and nonhaemolytic enterotoxin (NHE) production were assessed using the Duopath® Cereus Enterotoxins Test kit. The Kirby–Bauer disc diffusion method was applied as antibiotics susceptibility test. PCR was used to detect Emetic toxin gene (CES and CER) and enterotoxigenic toxin gene (cytK, nheA, hblC, and entFM). Results show a significant prevalence of B. cereus (42%) in spices. However, the spices meet food safety recommendations (<104 cfu/g). Antibiotics susceptibility test show alarming rate of resistance to beta-lactam antibiotics specially ampicillin (83.33%) and penicillin (82.14%). Concerning the toxin producing capacity more than half of the isolates (51.19%) produce NHE toxin and 27.38% produce HBL toxin. The most abundant gene were nheA, nheB, and nheC and a combination of 4 genes (entFM, nheA, hblC, and cytK) was detected in many isolates. In conclusion, the presence of multidrug resistant B. cereus strains carrying diarrhoeal toxin-encoding genes in spices intended for human consumption represents a serious health hazard. These results indicate the need for regular surveillance of the occurrence of B. cereus strains in spices and food products in Iran.
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