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Bacteriophage-based Biocontrol of Escherichia coli O157:H7 in Beef: Investigating Sprayed Wraps for Enhanced Food Safety
Get PDFBackground and Objective: Escherichia coli O157:H7, a major foodborne bacterial pathogen, is commonly detected in the intestines of healthy cattle, deer, goats and sheep. It can readily contaminate veal, ground beef and hamburgers, causing a range of human diseases, including mild diarrhea, hemorrhagic colitis, hemolytic-uremic syndrome and thrombotic thrombocytopenic purpura. Various treatment strategies are used to reduce E. coli O157:H7 contamination, ranging from washing to chemical and physical food decontamination. The increase of antibiotic-resistant bacteria has hence increased interest in lytic bacteriophages as biocontrol agents. This study investigated the use of bacteriophages to control E. coli O157:H7 growth in experimentally contaminated meat.
Material and Methods: Six E. coli O157:H7 specific bacteriophages were isolated from sewage, purified via plaque assay and assessed individually and in cocktails for lytic activity at various multiplicity of infection rates. Temperature-dependent effects on adhesion and lytic efficiency were assessed at refrigeration and ambient conditions. Phages were further used in commercial polyethylene food wraps to assess realistic surface delivery performance on inoculated meat samples and long-term phage stability was monitored during storage at 4 °C.
Results and Conclusion: Single-phage treatments achieved up to 100% bacterial elimination at higher multiplicities of infection, while optimized phage cocktails completely eradicated bacteria. Temperature affected bacterial recovery, with refrigeration decreasing bacterial adhesion and slightly slowing phage-mediated lysis. Importantly, this study has introduced an innovative practical approach using phages onto commonly used commercial polyethylene plastic wraps, demonstrating 99 and 93% reductions when phage‑treated wraps were used after 20 min and 24 h storages, respectively. Long-term storage of phage tf1 at 4 °C for seven months demonstrated stable plaque-forming ability, verifying durability for practical uses. These results highlight bacteriophages as effective, safe and scalable interventions to control E. coli O157:H7 in meat products, providing a practical strategy to enhance food safety, particularly for pathogens with extremely low infectious doses.
Keywords: Bacteriophage biocontrol, Escherichia coli O157:H7, Food safety intervention, Meat contamination, Phage cocktail therapy, Polyethylene wrap application
Introduction
Escherichia coli O157:H7 was identified in 1983 and has since been addressed as a major foodborne bacterial pathogen affecting humans [1, 2]. It is commonly detected in the intestines of healthy cattle, deer, goats and sheep and can therefore readily contaminate veal, ground beef and hamburgers [3]. The E. coli O157:H7 produces Shiga toxins and is classified as an enteric bacterium responsible for diarrhea and dysentery, also known as enterohemorrhagic E. coli (EHEC) [4]. It causes a range of human diseases, including mild diarrhea, hemorrhagic colitis (HC), hemolytic-uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) [5]. Although other foodborne pathogens such as Listeria, Salmonella enterica Serovar Enteritidis and Shigella species have been isolated from meats, E. coli O157:H7 is particularly concerning due to its extremely low infectious dose, as few as 10 cells, and its ease of transmission during slaughter and meat processing [6]. The microorganism can spread directly from person to person, especially in child day-care settings and from animals to humans [7].
Globally, E. coli infections are estimated to cause 2.8 million cases annually, with approximately 63,000 cases of HC reported each year in the United States alone. Children are particularly susceptible to severe complications such as HUS, a leading cause of acute renal failure (ARF) [8]. Numerous studies have investigated the prevalence of E. coli O157:H7 in food products and the bacterium has been isolated from a variety of plant and animal-derived foods within several countries. Contamination is frequently associated with meat products due to exposure to intestinal contents during slaughter and processing. However, contamination has been reported in raw fruits and vegetables, often linked to the use of untreated animal waste or contaminated irrigation water. Reported prevalence rates vary by country and food type, but the detection of the pathogen in ready-to-eat foods highlights the risk of foodborne illness outbreaks [9]. From 2003 to 2012, 390 outbreaks of Shiga toxin-producing E. coli O157 in the United States led to 4,928 diseases, 1,272 hospitalizations and 33 deaths, with cattle serving as the primary reservoir and ground beef as the most common route of transmission. Undercooked ground beef and other non-intact cuts pose a high risk, making it critical to decrease contamination during beef production, processing and storage and to protect consumers through appropriate handling and cooking of raw beef products [10].
Despite the urgent need to control E. coli O157:H7 contamination, current treatment methods vary in effectiveness and present challenges. To effectively decrease or eradicate E. coli O157:H7 contamination, a variety of treatment methods are currently used, ranging from simple washing of foods to chemical (peroxyacetic acid, chlorine dioxide, sodium hypochlorite and organic acids) or physical (irradiation, pasteurization, high-pressure processing and pulsed electric fields) decontamination techniques. These methods vary in their efficacy, costs and effects on the sensory quality and visual appeal of foods. However, their practical use is limited because several of these treatments can modify texture, flavor and nutritional attributes and some also increase concerns associated to residue safety and toxicity. Furthermore, they are not universally usable within all food types, which limits their feasibility and consistency in real processing environments [11]. Although antibiotics are used as effective chemical agents for removing these bacteria, increasing reports of antibiotic-resistant bacteria suggest that an alternative effective method is needed [12]. The growing threat of multidrug-resistant bacterial pathogens necessitates urgent investigation of alternatives to traditional antibiotics [13].
Regarding the limitations of current treatments, bacteriophage therapy, first developed by Felix d’Herelle and historically overshadowed by antibiotics, has re-emerged as a promising alternative to traditional antibiotics. This is due to its specificity, ability to target biofilms, minimal side effects and potentials to decrease antibiotic resistance development [14]. In food safety, bacteriophages offer unique advantages because of their narrow host range, which enables them to eliminate pathogenic E. coli strains without harming beneficial microbiota [15]. Coliphages, in particular, are abundant in environments such as sewages, animal wastes and water sources, making them accessible for isolation and use against foodborne pathogens [16]. One challenge to their use is the possible emergence of phage-resistant bacteria; however, this can be addressed through the use of phage cocktails composed of multiple phages with complementary host specificities. Such formulations not only broaden the range of susceptible bacterial targets but also decrease the likelihood of resistance development. Moreover, phages include the ability to evolve in bacteria, allowing them to overcome resistance mechanisms that limit the effectiveness of antibiotics. These characteristics have provided a way for regulatory acceptance of several phage-based products in the food industry, particularly for the control of E. coli O157:H7 in beef and fresh products, highlighting their potential as sustainable and innovative tools to enhance food safety [17].
Bacteriophages have been recognized as safe for use in food production and are classified as generally recognized as safe (GRAS) by the U.S. Food and Drug Administration (FDA). While phages targeting E. coli O157:H7 such as EcoShield and SecureShield E1 have received GRAS approval for use in beef and other food products, similar approvals exist for phages against other foodborne pathogens. The GRAS phages are valued for their specificity, safety for human consumption, minimal effects on the food sensory characteristics and ability to decrease pathogen levels without contributing to antimicrobial resistance [18]. This research investigated the use of bacteriophages as biocontrol agents to control the propagation of artificially contaminated E. coli O157:H7 in meat samples.
Materials and Methods
2.1. Bacteria cultivation
Lyophilized E. coli O157:H7 PTCC 1860 was provided by the Persian Type Culture Collection (PTCC), Iran. The strain was cultured on tryptic soy agar plates at 37 °C for 16–18 h. For storage, bacterial cultures were suspended in tryptic soy broth (TSB) with 15% glycerol and stored at -80 °C. Bacterial counts were determined as colony-forming units (CFU) defined as viable bacterial cell capable of forming a visible colony on solid media.
2.2. Isolation and purification of bacteriophages
Bacteriophages were isolated from environmental water, sewage and slaughterhouse sewage samples. Briefly, 100 mL of sewage samples were collected in sterile bottles and transported to the laboratory. To enrich bacteriophages, samples were mixed with 200 mL of TSB media and inoculated with the E. coli host and then incubated overnight at 37 °C. Chloroform was added to the mixture for 10 min to lyse the bacterial cells, followed by centrifugation to remove debris. The resulting supernatants, containing potential bacteriophages, were assessed against host bacteria using double-layer agar method [19]. After overnight incubation at 37 °C, plates were investigated for plaques. Single plaques were isolated and subjected to repeated culture using double-layer agar technique to purify individual bacteriophages. Isolated bacteriophages were stored in SM buffer at 4 °C. Phage titers were expressed as plaque-forming units (PFU), where one PFU corresponded to an infectious phage particle that produced a visible plaque on a bacterial lawn.
2.3. Contaminated-meat experiments
Fresh beef was purchased from a local butchery and cut into similar pieces. Their sterility was assessed before use. For experimental contamination, E. coli O157:H7 was cultured overnight and a bacterial suspension was prepared at a concentration of 10⁷ CFU.mL-1. Meat samples were immersed in the suspension and agitated for 10 min to allow bacterial adhesion. The multiplicity of infection (MOI) was reported as the ratio of phage particles (PFU) to bacterial cells (CFU).
2.3.1. Single Phage Treatment
Meat samples were divided into three groups and suspended in sterile water, including untreated meat (control), meat treated with E. coli O157:H7 at 10⁷ CFU.mL-1 (bacteria only), meat contaminated with E. coli O157:H7 (10⁷ CFU.mL-1) and subsequently treated with a specific bacteriophage at 10⁸ PFU.mL-1 (phage-treated). All samples were agitated for 20 min; after which, aliquots were serially diluted (10-¹, 10-² and 10-³) for plating on eosin methylene blue (EMB) agar. Sampling and culturing were repeated after 60 min to assess bacterial decrease over time. The entire procedure was carried out at room temperature (RT) and 4 °C to assess the effect of temperature on phage efficacy.
2.3.2. Phage Cocktail Treatment
A mixture of three bacteriophages (TF1, TF2 and SC) was used in meat samples inoculated with E. coli O157:H7 (10⁷ CFU.mL-1) at a total phage concentration of 10⁸ PFU.mL-1. To further assess the cocktail performance, an additional trial was carried out; in which, each phage was used individually at 10⁸ PFU.mL-1.
2.4. Contaminated ground beef experiments
Ground beef was prepared from the meat under sterile laboratory conditions and divided into three portions of equal weight. One portion was untreated as a control. The second portion was inoculated with E. coli O157:H7 at a concentration of 5 × 10⁸ CFU.mL-1 without further treatment. The third portion was similarly contaminated with the bacteria, agitated for 20 min to ensure homogenized distribution and then treated with a bacteriophage suspension at 10⁸ PFU.mL-1. These experiments were carried out at RT and 4 °C.
2.5. Plastic wrap treatment with bacteriophages
Beef samples were covered with plastic wrap under various conditions. The wrap included commercial food-grade low-density polyethylene available in the market. In the control setup, uncontaminated beef was wrapped with untreated plastic. A second setup involved contaminated beef wrapped with plastic that did not contain bacteriophages. In the phage-treatment setup, plastic wrap was pretreated with a suspension containing 10⁹ PFU.mL-1 bacteriophages by spraying and storing at 4 °C for 20 min and then used in contaminated beef for 30 min at 4 °C. To further assess the protective effect of wraps over time, additional plastic sheets were incubated at 4 °C for 24 h after sprayed with the phage suspension followed by covering beef samples for 30 min.
2.6. Statistical analysis
All experiments were carried out in three replicates (n = 3). Quantitative data were presented as mean ± SD (standard deviation). Error bars in figures represented SD of the replicates.
Results and Discussion
Four bacteriophages were isolated from municipal sewage and two others from slaughterhouse wastewater. These were designated as tf1-tf4 and sc-sg, respectively. Of the six bacteriophages isolated, tf1 was chosen for further individual assessments based on its distinct plaque morphology. This produced large, clear and well-defined plaques, suggesting high lytic efficiency and strong bactericidal potential against E. coli O157:H7. In contaminated beef experiments, when 106 PFU.mL-1 of tf1 bacteriophage was used at RT against 107 CFU.mL-1 of E. coli O157:H7, 65% ±0.5 of bacteria were removed after 20 min (MOI = 0.1) at RT. Increasing phage dose up to 109 PFU.mL-1 led to 99% ±0.4 bacterial elimination (MOI = 100), as shown in Figure 1.
Exposure with phage for 60 min at RT, addition of 107 PFU.mL-1 of phage to 106 CFU.mL-1 of bacteria resulted in nearly 93.5% ±0.4 elimination (MOI = 10). However, bacteria were more effectively removed, when treated by 108 PFU.mL-1 phage even up to 99% ±0.2 (MOI = 100). Elimination rate was 100%, when 109 PFU.mL-1 of phage was added to 107 CFU.mL-1 of bacteria (MOI = 1000), as shown in Figure 2. Bacterial decreases are shown at the second y axis (right y axis).
For assessing the effect of phage cocktail, including tf1, tf2 and sc, cocktails with two various formulas were assessed. Meat containing 107 CFU.mL-1 bacteria was exposed to a dose of 108 PFU.mL-1 cocktail phages and showed nearly 99% ±0.1 of bacteria being lysed after 20 min and 99.5% ±0.1 after 60 min. When a cocktail included 108 PFU.mL-1 separately, bacterial removal was 100%; as shown in Figure 3. Comparison of performance between single-phage (Figure 1-2) and cocktail treatments (Figure 3) indicated that while tf1 alone achieved strong bacterial decrease at higher MOIs, the cocktails demonstrated enhanced efficacy and reliability in reaching levels below infectious (< 100 CFU) and ingestion (< 10 CFU) thresholds. The optimized cocktail not only maintained 99% bacterial elimination but achieved complete eradication when used at equivalent individual phage titers, demonstrating superior robustness in ensuring bacterial counts fall below clinically relevant exposure limits.
In ground beef experiments, meat samples were inoculated with E. coli O157:H7 at an initial concentration of 107 CFU.mL-1 and then treated with 108 PFU.mL-1 of bacteriophages for either 20 or 60 min at 25 and 4 °C. Bacterial recovery from the meat was affected by temperature, as adhesion decreased at refrigeration temperature, compared to ambient conditions, consistent with the lower metabolic activity and decreased surface interactions of bacteria at colder environments. After 20 min of phage exposure, bacterial counts decreased by 96.4% ±0.1 at 25 °C and 82.0% ±0.4 at 4 °C (Figure 4). When exposure time was extended to 60 min, decrease rates increased to 99.95% ±0.05 and 87.0% ±0.5 at 25 and 4 °C, respectively, indicating that phage-host interactions were kinetically dependent, with higher temperatures favoring further efficient adsorption and subsequent lysis. These findings suggested that rapid refrigeration of meat could decrease infection risk by limiting bacterial attachment, even though phage-mediated lysis occurred further slowly at lower temperatures
Contaminated meat samples were covered for 30 min with plastic wraps coated with 109 PFU.mL-1 phage for 20 min and 24 h. significant viable cell decreases, at the two conditions were observed with the greatest decrease in the 20 min-treated plastic wrap, compared to controls without phages. This included 99.0% ±0.9, compared to 93% ±2 in 24 h-treated group; as shown in Figure 5.
To assess the long-term stability of phage tf1, its plaque-forming ability was assessed over a 7 m storage at 4 °C. At a 10⁻⁷ dilution, plaque counts were consistent within all measured time points, showing no appreciable decreases in infectivity (Figure 6). The average plaque count calculated from all sampling intervals was stable, further verifying the persistence of active phage particles during prolonged storage. Minor deviations observed between the months were included within the expected range of experimental variability, which might be seen due to the counting precision or inherent assay fluctuations. Overall, these results indicated that phage tf1 preserved its infective capacity and structural integrity for at least 7 m under refrigerated conditions, highlighting its strong potential for use in long-term biocontrol uses.
The EHEC are pathogenic E. coli strains that produce Shiga toxins and cause HC and its life-threatening sequelae of HUS [20]. Since identification of serotype O157:H7 in 1983, many outbreaks associated with EHEC have been reported in the United States and E. coli O157:H7 has become one of the most important foodborne pathogens [21]. It causes severe human disease worldwide. It seems important to eliminate this pathogen in appropriate way [5]. Antibiotics were always an option; however, with increasing antibiotic-resistant strains due to use of antibiotics in cow feed, an alternative treatment is needed [22].
In a study, the overall prevalence of Shiga toxin-producing E. coli in raw beef samples collected from an industrial slaughterhouse in Hamadan, Iran, was 10.4%, with one isolate (12.5%) belonged to the O157 serogroup and the rest isolates of 87.5% classified as non-O157. The prevalence of O157 (1.3%) was similar to that reported in Iran (e.g., 1.35% in Mashhad), greater than those reported from the EU (0.3%), the U.S. (0.8%) and Brazil (1%) and less than those reported in Nigeria (2.2%) and Australia (1.7%). The study verified cattle as a reservoir for Shiga toxin-producing E. coli and highlighted seasonal and animal-associated factors such as spring sampling and the use of feeder cattle, which might contribute to the prevalence [23]. Additionally, they reported that 5.3% of raw poultry meat samples were contaminated with E. coli O157 strains. Out of 257 samples, 36% of the samples contained E. coli isolates, with 38.7% of the isolates identified as Shiga toxin-producing E. coli carrying virulence genes such as stx1, stx2 and eae. The isolates showed significant genetic diversity and high resistance to antibiotics, including nalidixic acid, tetracycline, ampicillin and trimethoprim-sulfamethoxazole [24].
Since discovery of bacteriophages, they included therapeutic potential as natural enemies of bacteria and phase-based elimination of bacteria in agriculture and food industry was started [25]. Therefore, bacteriophages have been reported as good antibiotic alternatives. They provide a highly specific, environmental-friendly effective means of controlling bacterial pathogens in agriculture; thereby, contributing to efforts against the increase of antibiotic resistance in the food sector [26].
This study aimed isolation of effective bacteriophages for biocontrol of E. coli O157:H7 in beef and ground beef. Six phages were isolated and assessed in suspension and spray methods on beef and beef ground samples at RT and 4 °C. The use of the submersion method to assess bacterial attachment to meat showed less bacterial recovery at 4 °C, compared to 25 °C, verifying that adhesion and phage inactivation efficiency were modulated by temperature, likely due to differences in bacterial physiology and phage adsorption kinetics. These findings highlighted the importance of environmental conditions and exposure time in optimizing phage-based biocontrol strategies in meat systems. Furthermore, the effect of various MOIs were assessed after incubation times of 20 and 60 min. The results showed that the phage treatment eliminated 82 to 100% of E. coli O157:H7. Phage cocktails included a better elimination rate. In a similar study, a cocktail of all three phages was assessed for their ability to lyse the bacterium in vivo and in vitro. The phage cocktail totally eradicated E. coli O157:H7 from beef surfaces in seven out of nine experiments. They have isolated phages from bovine farmyard slurry samples. The study achieved superior results when using phage cocktails similar to those used in this study, suggesting that a combination of multiple phages could enhance the effectiveness against the target bacteria. Another bacteriophage cocktail of three lytic phages for E. coli O157:H7 was investigated for its ability to decrease experimental cont
Lipid Profile of Children With Nephrotic Syndrome Admitted to a Tertiary Care Hospital: Lipid Profile in Nephrotic Syndrome
No full textBackground and Aim: Hyperlipidemia is typically detected in active nephrotic syndrome(NS) and normalizes with the resolution of the proteinuria. This study assessed the lipidprofile of children with NS during active disease and remission.Methods: This prospective observational study was conducted at ICMH, Bangladesh, fromJuly 2021 to June 2022. Sixty children with NS (1-18 years), including both first attack andrelapse cases, were enrolled. A detailed history and thorough clinical examination were carriedout. Serum fasting lipid profiles were measured during active disease and again 4 weeksafter achieving remission. After collecting all the required data, analysis was conducted usingSPSS software, version 24.0.Results: The majority of children (70%) were relapse cases. The mean age of the studyparticipants was 5.15±2.97 years, with a predominance of males (61.7%). Mean serumcholesterol, low-density lipoprotein (LDL), and triglycerides (TG) levels were elevated inall groups, while high-density lipoprotein (HDL) levels were normal in all groups duringactive disease. During remission, serum cholesterol, TG, and LDL levels were significantlyreduced in both first attack and relapse cases. LDL levels returned to normal in all groups,but total cholesterol (TC) and TG remained high in the frequently relapsing NS (FRNS) andsteroid-dependent NS (SDNS) groups. Serum albumin levels were low in all groups, withsignificantly lower levels observed in the FRNS group.Conclusion: During active disease, serum cholesterol, TG, and LDL levels were elevated inboth first attack and relapse cases. Serum TC and TG remained persistently high in FRNSand SDNS
Endodontic Management of a C-shaped Mandibular Second Premolar with Four Canals and Four Apical Foramina: A Case Report
Get PDFA thorough understanding of root canal morphology is critical for achieving predictable outcomes in endodontic therapy. Anatomical variations in mandibular second premolars are uncommon compared to other teeth, and the coexistence of a C-shaped root canal configuration with four independent canals and four separate apical foramina is exceptionally rare. This case report describes the nonsurgical endodontic management of a mandibular second premolar exhibiting this unique morphology, confirmed through cone-beam computed tomography (CBCT) and magnification. A 52-year-old male was referred by a prosthodontist for elective root canal treatment before post placement. CBCT imaging revealed a C-shaped root in the coronal third that bifurcated into four separate canals at the midroot level, each terminating in an independent apical foramen. Nonsurgical treatment was performed over two visits, using meticulous chemo-mechanical preparation, intracanal calcium hydroxide dressing, and warm vertical compaction obturation. At the 9-month follow-up, the tooth was functional, asymptomatic, and radiographically stable. This case underscores the importance of preoperative assessment with advanced imaging and magnification in identifying and successfully treating rare endodontic anatomies
Guided Endodontic Management of Pulp Canal Obliteration in a Maxillary Canine with Root Resorption and Prior Iatrogenic Deviation: A Case Report
Get PDFThis case report describes the successful guided endodontic treatment of a maxillary left canine (#23) with pulp canal obliteration (PCO) in a 30-year-old female patient. The patient had a history of orthodontic treatment and Le Fort I orthognathic surgery, both recognized as potential factors contributing to canal calcification. The patient had a history of a failed root canal treatment, contributing to incomplete canal instrumentation and iatrogenic damage (gouging) during access cavity preparation. The case was referred for completion of treatment. Upon referral, clinical and radiographic examinations revealed advanced canal obliteration, procedural gouging from the prior attempt, and a radiolucent line suggestive of a horizontal root fracture. Cone-beam computed tomography (CBCT) confirmed the extent of canal calcification, ruled out the suspected fracture, and showed a localized palatal external root resorption, likely related to previous orthodontic forces. Given the complexity of the case, a static-guided endodontic technique was selected as the preferred treatment approach. A custom 3D-printed guide, generated from merged CBCT and intraoral scan data, enabled conservative and accurate access to the calcified canal. Although a hand K-file fractured during canal negotiation, the fragment was successfully retrieved using ultrasonic devices under magnification. The tooth was treated successfully. Clinical and radiographic follow-ups at six and twelve months confirmed resolution of the periapical lesion and complete symptom relief, demonstrating that guided endodontics can serve as a safe and effective treatment option in teeth with PCO
Prolonged Penile Erection in an Adolescent with Angelman Syndrome under Aripiperazole: A Case Report: Prolonged penile erection in Angelman syndrome
No full textAngelman syndrome (AS) is a genetic neurodevelopmental disorder characterized by mental retardation, ataxia, and happy social behavior. Aripiprazole is an atypical antipsychotic drug used for treating irritability in patients with autism spectrum disorder in > 6-year-old children and adolescents. Notably, prolonged penile erection is an unknown complication of Aripiprazole. Therefore, the present case report aimed to present a unique prolonged penile erection in an adolescent with Angelman syndrome under Aripiprazole. In this case report, priapism occurred several hours after consuming 5 mg of Aripiprazole. Since he was neither a cigarette smoker nor an alcohol abuser, had no medical issues, and did not report any history of penile or perineal trauma, the urologist suggested that the priapism he experienced might be linked to the use of Aripiprazole. Fortunately, he recovered after stopping the medication. Generally, we mentioned controversial results from previous case reports on the effect of Aripiprazole. It is unknown why some case reports noted priapism post Aripiprazole use, and some mentioned priapism palliation by switching to this drug from other antipsychotics. While it seems that the tendency to priapism may be an idiosyncratic reaction or the α1-adrenergic receptors change or disorders in the predisposed patient, there is a need for further comprehensive studies on this issu
Pediatric-Onset Neuromyelitis Optica Spectrum Disorder in Isfahan: Insights from a Cross-Sectional Study
Get PDFObjectives:
Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune demyelinating disease of the central nervous system. While NMOSD predominantly affects adults, pediatric-onset NMOSD (PONMOSD) cases are increasingly recognized, necessitating a better understanding of the disease in this population. This study aims to provide a comprehensive insight into the manifestations and management of PONMOSD.
Material & Methods:
This study was conducted at the Isfahan MS Clinic, Iran, recruiting 182 NMOSD patients between March 2021 and March 2022. Board-certified neurologists performed diagnosis and examination, applying the 2015 NMOSD diagnostic criteria. Clinical data were collected and analyzed, including demographic information, onset symptoms, family history, treatment, and MRI findings.
Results:
Eighteen patients with PONMOSD (9.9% of the total) were identified. The study cohort had a female-to-male ratio 2.6:1, with the most common onset symptoms being optic neuritis (ON) and transverse myelitis (TM). AQP4-Ab was positive in 66.7% of the patients, with longitudinally extensive transverse myelitis (LETM) being the most common MRI finding. Azathioprine and Rituximab were the most commonly used treatments in patients, respectively. Treatment response was generally favorable, with most patients responding to therapy.
Conclusion:
The present study provides valuable insights into the clinical characteristics and management of pediatric-onset NMOSD. Despite challenges in diagnosis and treatment, early recognition and appropriate management strategies can lead to improved outcomes in this population. Further research is needed to optimize diagnostic criteria and therapeutic approaches for pediatric NMOSD
The Epidemiology of Epileptic Spasm and Affecting Factors on One-Year Prognosis: A Study in Tabriz Children’s Hospital
No full textObjectives:
Epileptic Spasm (ES) is a special type of convulsive disorder that primarily occurs in infants, typically within the first year of life. This disorder is usually resistant to routine anticonvulsant drugs. This study aims to evaluate the epidemiology and factors affecting one-year prognosis in patients with ES in Tabriz Children’s Hospital.
Materials & Methods:
This descriptive-analytical cross-sectional study focused on patients diagnosed with ES who were referred to the neurology department of Tabriz Children’s Hospital between 2015 and 2019. Data was collected using a census sampling method and a checklist that included demographic information and clinical and treatment histories. The results were then reported statistically.
Results:
Thirty-seven patients were studied, with 15 (40.5%) exhibiting flexor seizures, eight (21.7%) extensor seizures, and 14 (37.8%) mixed seizures. The most common causes were prenatal insult (10 cases, 27.0%), cryptogenic (9 cases, 24.3%), and Central Nervous System (CNS) malformations (6 cases, 16.2%). Electroencephalography findings included modified hypsarrhythmia in 12 cases (30.8%), hypsarrhythmia in 16 (41.0%), and frequent epileptiform discharge in nine (23.1%). MRI and CT scans showed abnormalities in three cases (8.1%) and 16 cases (43.2%), respectively. Treatment involved Phenobarbital in 35 patients (94.6%), Vigabatrin in 29 (78.4%), and ACTH in 11 (29.7%). The one-year prognosis indicated 25 patients (67.6%) experienced disease recurrence, seven (18.9%) recovered with complications, and two (5.4%) died.
Conclusion:
The most common causes of ES are prenatal insults, cryptogenic factors, and CNS malformations. The key one-year prognoses include disease recurrence and recovery with complications
The Role of Demographic Characteristics and Personality Traits in COVID-19-Related Anxiety and Preventive Behaviors
Get PDFIntroduction: This study aimed to evaluate the role of demographic characteristics and personality traits in ascertaining the severity of COVID-19 induced anxiety and the effectiveness of preventive behaviors among university students in Iran.
Materials and Methods: This descriptive-correlational study included a sample of 203 students (47 males and 156 females) enrolled in universities located in Mashhad (Iran) in 2021. Data collection was conducted using standardized questionnaires such as COVID-19anxiety questionnaire, Big Five personality traits, Preventive behaviors, and demographic characteristics through online platforms via social media to comply with health protocols. Data analysis was performed using SPSS version 26. Descriptive statistics, independent t-tests, Pearson correlation coefficients, and stepwise regression analyses were conducted to analyze the data.
Results: The findings from the regression analysis indicated that the personality traits of agreeableness and conscientiousness significantly elucidated the variability in COVID-19 anxiety. Specifically, agreeableness emerged as a significant predictor of preventive behaviors. Furthermore, this study revealed that male students exhibited higher anxiety levels than their female counterparts, while females demonstrated a greater engagement in preventive behaviors. Moreover, the consumption of substances and alcohol was associated with heightened anxiety and diminished preventive behaviors.
Conclusion: The results underscore the necessity of considering both demographic characteristics and personality traits when designing interventions that aim at mitigating health crises. Notably, the traits of agreeableness and conscientiousness may help reduce anxiety and promote preventive behaviors within such contexts
Phylogenetic Groups and Antimicrobial Resistance among Uropathogenic Escherichia coli Isolates from Hospitalized Patients in Tehran
Get PDFBackground: The presence of Escherichia coli among uropathogens is increasing significantly worldwide. It accounts for a considerable amount of morbidity and high medical costs and also can lead to mortality. The current research aims to investigate E. coli antimicrobial susceptibility patterns and the molecular causes of E. coli resistance trends and virulence factors among phylogenetic groups of Uropathogenic Escherichia coli (UPEC) in Urinary tract infection (UTI) patients in a hospital in Tehran, Iran. The antimicrobial susceptibility of urinary E. coli isolates.
Materials and Methods: The antimicrobial susceptibility of urinary E. coli isolates was tested using the Kirby-Bauer agar disc diffusion method. In addition, resistance and virulence genes were monitored by polymerase chain reaction (PCR), and the clonal relation of isolates was studied by pulsed-field gel electrophoresis (PFGE).
Results: Studied isolates showed the highest susceptibility rates to MEM (95.7%), followed by TZP (90%). In contrast, resistance rates were found for AMP (100%), SXT (74%), and CIP (51.5%). ESBL-producing isolates were positive for blaTEM, blaCTX-M, and blaSHV by PCR, respectively. According to the adhesion gene analyses, fimH (85.8%) was the most prevalent among E. coli isolates, followed by aer (49.7%), hlyA (46.1%), and pap (38.9%). A total of 57 PFGE patterns and three clusters (A–C) were identified by the PFGE method. (cluster A: Non-ESBL & Sensitive to all Antibiotics use; Cluster B: The most common cluster in terms of TEM, CTX-M, or both; Cluster C: containing CTX-M gene and resistant to ceftriaxone and ciprofloxacin).
Conclusion: Our data showed ESBL rates were high in UTI E. coli isolated in the studied hospital. The UPEC isolates exhibited a high resistance rate to first- and second-generation cephalosporins and fluoroquinolone, which could result in serious public health risks. The relationship between virulence factors and resistance genes is complex and needs more studies specific to each area