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نقش ابن جزّار در توسعه دانش پزشکی و داروسازی مغرب اسلامی
No full textBackground and Aim: Muslims studied medical sciences in the third century AH After translating the works of other peoples and each land in their vast territory contributed to the growth and development of this scientific heritage. The Islamic Maghreb, which extended from the west of Egypt to the shores of the Atlantic Ocean, played a major role in cultivating great physicians and pharmacists and presenting the works and results of their efforts to humanity. This study aims to explain Ibn Jazzar’s role in the development of medical knowledge and pharmacy in Islamic Maghrib.
Methods: The method is descriptive-analytical, library and based on historical data and statements. After reviewing historical sources and references, the materials was categorized, data analyzed and the article was written.
Ethical Considerations: The ethical aspects of library research, including the originality of texts, honesty and trustworthiness, have been observed.
Results: The findings show that Ibn Jazzar, a famous Moroccan physician and pharmacist, in addition to practicing medicine, paid attention to producing medical knowledge through studying and comparing the medical works of Greek predecessors and writing numerous works in the fields of medical knowledge, botany and pharmacy.
Conclusion: The results which were obtained through answering the research questions show that Ibn Jazzar Maghrib grew up in the stable conditions of the Fatimid era and his family profession, which was medicine, led him to this profession. In addition to medicine, he also paid special attention to pharmacy, which provided the basis for the separation of these sciences. Ibn Jazzar left behind valuable works in the fields of medicine and pharmacy and played an important role in expanding the scientific and civilizational boundaries of Islam in the field of medical sciencesزمینه و هدف: مسلمانان پس از ترجمه آثار اقوام دیگر، مطالعه علوم پزشکی را از قرن سوم قمری آغاز نمودند و هر سرزمینی از قلمرو پهناور آنان به سهم خود در رشد و بالندگی این میراث علمی کوشید. سرزمین مغرب اسلامی که از غرب سرزمین مصر تا سواحل اقیانوس اطلس را دربر میگرفت، در پرورش پزشکان و داروسازان بزرگ و تقدیم آثار و نتایج زحمات آنان به بشریت سهم عمدهای داشت. هدف از این پژوهش تبیین نقش ابن جزّار در توسعه دانش پزشکی و داروسازی مغرب اسلامی است.
روش: روش این تحقیق توصیفی ـ تحلیلی، کتابخانهای و مبتنی بر دادهها و گزارههای تاریخی است و پس از فیشبرداری از منابع و مأخذ تاریخی، به دستهبندی مطالب، تحلیل دادهها و نگارش مقاله اقدام شده است.
ملاحظات اخلاقی: در پژوهش حاضر جنبههای اخلاقی مطالعه کتابخانهای شامل اصالت متون، صداقت و امانتداری رعایت شده است.
یافتهها: یافتههای تحقیق نشان میدهد که ابن جزّار، طبیب و داروساز معروف مغربی، ضمن طبابت اهتمام فراوانی به تولید دانش پزشکی از طریق مطالعه و مقایسه آثار پزشکی متقدمین یونانی و تألیف آثار متعدد در حوزه دانش پزشکی، گیاهشناسی و داروسازی داشته است.
نتیجهگیری: نتایج این پژوهش که از طریق پاسخ به پرسشهای تحقیق حاصل شده است، نشان میدهد که ابن جزّار مغربی در اوضاع باثبات عصر فاطمیان رشد و نمو یافت و پیشه و حرفه خانوادگیاش که طبابت بود، او را به سوی این حرفه سوق داد. او ضمن طبابت، به داروسازی نیز به صورت تخصصی توجه داشت و موجبات تفکیک این علوم را فراهم آورد. ابن جزّار آثار ارزشمندی در زمینههای پزشکی و داروسازی از خود بر جای گذاشت و نقش مهمی در گسترش مرزهای علمی و تمدنی اسلام در حوزه علوم پزشکی داشت
Biofilm Formation of Foodborne Pathogens and Strategies of Its Prevention and Biocontrol: A Review
Get PDFBackground and Objective: Foodborne pathogens and cross-contamination of food products pose a serious risk to the food industry as many outbreaks are associated with biofilm formation, which increases post-processing contaminations and risks to public health. This review aimed to study the biofilm formation of spoilage and pathogenic bacteria in foods and on food contact surfaces, which subsequently represent serious challenges to the food industry and may decrease shelf life and increase transmission of diseases.
Results and Conclusion: Chemical and physical methods (e.g. sanitizing with chemicals and heat treatment) are not sufficiently applicable for biofilm removal in food sectors due to the increase of bacterial resistances, ingredient damages and possible residues in food matrix. During meat processing, the environment is filled with complex multispecies communities of microorganisms, majorly connected to the surface forming biofilms that are difficult to treat. Furthermore, bacterial cell relationships between various genera and species play a key role in the attachment process and formation of strong biofilms, as well as in the resistance of the biofilm community members against antimicrobial treatments. Thus, control of these biofilms are difficult in food industries since the biofilm cells secrete exopolymeteric substances that include preventing barrier or lessening contact with environmental stresses such as antimicrobial agents as well as the host immune system. Biofilms are highly resistant to conventional antimicrobial therapies and lead to persistent infections. Hence, there is a high need for novel strategies other than conventional antibiotic therapies to control biofilm-based infections. Bacterial biofilm formation and its problems in the food industry were discussed in this study in addition to various safety strategies aiming to provide novel insights into biofilm control in the food industry for improving food quality and safety.
Conflict of interest: The authors declare no conflict of interest.
Introduction
A biofilm is a complex community of microorganisms that adhere to a surface, forming multiple layers that protect their growth, proliferation and survival [1]. It can lead to antibiotic resistances, nosocomial infections and food-borne illnesses. However, biofilms benefit the microbes by helping them in adhesion, metabolite exchange, quorum sensing and drug resistance [2]. Microbial biofilms are composed of diverse bacteria surrounded by their exopolysaccharides and typically attached to biotic and abiotic surfaces, resulting in food poisoning with diarrhea, vomiting, enteritis, stomach discomfort and headaches in humans [3, 4]. Presence of biofilms in food-processing environments, food contact surfaces, processing equipment such as stainless steel, rubber, plastic and Teflon and completed products increases danger of spoiling, diminishes shelf life and increases possibilities of infectious disease outbreaks associated with foods [5]. Search for efficient ways to control microbes and their biofilms still needs further efforts [6]. This review covered topics associated with particular microorganisms that create biofilms in the food sector, illustrating the biofilm formation process, stages of development, interactions between microorganisms and various novel methods and strategies of biocontrol.
Results and Discussion
Biofilm Formation
Several factors affect biofilm formation, including metabolism, signaling molecules, culture media, matrix and variations in cellular and genetic makeup [7]. Generally, biofilm formation consists of four common steps (Figure 1), initially produced on biotic or abiotic surfaces through reversible and irreversible adhesion, using adhesive proteins, lipopolysaccharides, flagella and pili [8]. Furthermore, biofilm maturation occurs in two stages of cell-to-cell communication and production of auto-inducer molecules. These molecules primarily consist of proteins, exopolysaccharides, DNA, RNA, enzymes, microbial cells and water with water being the major component responsible for nutrient movement within the biofilm matrix. Exopolysaccharides serve as a protective shield, enhancing microbial adhesion within biofilms, ensuring their structural integrity and facilitating nutrient acquisition [9,10,11].
1.1 Formation of Biofilm in Food Industry
In the food industry, surfaces and equipment that come into contact with foods are often occupied by microorganisms that can form biofilms [12,13]. Bacterial biofilms in foods pose severe hazards to human health, leading to systemic diseases, food intoxication and gastroenteritis and presence of bacterial biofilms on tables, staff gloves, animal carcasses, water, milk and other liquid pipelines has been documented [14].
1.2 Biofilm Resistance to Antimicrobial Agents
Bacteria living in biofilms show 10 to 1000-fold increases in drug resistance, compared to their planktonic stages. Various multidrug-resistant (MDR) bacteria such as Salmonella spp., methicillin-resistant Staphylococcus aureus (MRSA), Listeria monocytogenes, Campylobacter jejuni, Escherichia coli O157:H7 and vancomycin-resistant enterococci (VRE) have been linked to foodborne outbreaks, presenting a significant public health threat [15]. Based on the estimates, biofilm matrix and EPS prevent bacteria from antibiotic exposure, providing them an adaptive advantage by preventing chemical stressors from penetrating deeper biofilm regions [16]. In biofilms, quorum sensing and horizontal gene transfer are the most commonly observed mechanisms [17]. Biofilm awareness in fight against MDR bacteria needs further discussion and persistence of biofilms in foods creates an ideal environment for resistance mechanism exchange; hence, greater awareness of these dangers is necessary.
1.3 Quorum Sensing System
Quorum sensing system is a communication system between the cells that allows them to send chemical signals, enabling cooperative gene expression, which leads to increased population density, enhanced biofilm formation and increased production of extracellular polymeric substances [18]. Recent studies have shown that Gram-negative bacteria produce acylated homoserin lactones (AHLs) as autoinducers, while Gram-positive bacteria use peptides (AIPs) [19].
1.4 Horizontal Gene Transfer
Horizontal gene transfer is a widely recognized mechanism; through which, bacteria adapt and spread resistance to antimicrobial agents using mobile genetic elements (MGEs), which pose a significant threat to global public health [20]. Release and transfer of bacterial DNA play a role in biofilm synthesis and contribute to the spread of antibiotic resistance. Resistance plasmids can spread through the conjugation process, promoting development of resistant biofilms within the densely populated structure of biofilms. Over time, drug resistance leads to the preferential expression of certain genes, resulting in increased productions of proteins associated with virulence and antibiotic resistance, which can alter characteristics of biofilm resistance.
1.5 Common Foodborne Pathogens Forming Biofilms
Bacterial pathogens can contaminate meats because meats are rich in vitamins, minerals and proteins and include high water contents (75%) and acceptable pH ranges [21, 22]. The greatest dangers to food safety worldwide are environmentally hazardous microorganisms that can infect cattle during various processing procedures and foodborne illnesses associated with uncooked meats. These pollutants are challenging to clean off and disinfect, putting customers' health at major risks. A variety of bacterial pathogens can cause meat-borne diseases, by infecting animals or contaminating meat during meat processing such as Salmonella spp., E. coli, Campylobacter spp., L. monocytogenes, Yersinia enterocolitica, Brucella spp., Mycobacterium bovis, Bacillus anthracis and toxin-producing Staphylococcus aureus, Clostridium spp. and B. cereus [23]. Meat-borne diseases can be categorized into infections, intoxications, allergies, metabolic food disorders and idiosyncratic illnesses [24]. Harmful bacteria can build up on various equipment and biotic and abiotic surfaces and eventually create biofilms whereas over 90% of bacteria live. They create biofilms on gloves and surfaces of silicon, rubber plastic, glass and stainless steel [25]. Significance and effects of biofilms on the food industry have been demonstrated in several studies, where a variety of pathogens such as L. monocytogenes, Y. enterocolitica, C. jejuni, B. cereus and E. coli O157:H7 frequently cross-contaminate these food products [26]. Available studies have shown that the coexistence of multiple bacterial species could increase biofilm development and enhance pathogen persistence by promoting EPS production. Examples of these relevant biofilm-forming pathogens in the food industry are briefly described.
1.5.1 Gram-negative Bacteria
Approximately 80% of the available foods in Saudi Arabian markets are imported with 15.71% of these imports are meat-based. Escherichia coli, Salmonella spp. and Pseudomonas aeruginosa include several important virulence factors, form biofilms and easily contaminate meats. However, handling and consuming animal-derived products contaminated with E. coli biofilms can pose health risks while Shiga toxin-producing E. coli and Enterohaemorrhagic E. coli are important enteric pathogens linked to outbreaks and severe gastroenteritis. Verotoxigenic E. coli produce verotoxins while E. coli O157:H7 is a human pathogen responsible for outbreaks of bloody diarrhea and hemolytic uremic syndrome (HUS) and can be transmitted through raw milks, drinking waters, fresh meats and vegetables. A major element affecting production of E. coli biofilms is temperature. For example, after 7 d of incubation at 15 °C, quantity of adhering and planktonic cells increased on beef surfaces, which included a serious issue for meat processing plants [27]. Isolates with a higher capacity for mature biofilms showed resistance to sanitization [28].
Salmonella spp. propagate at 35–37 °C and includes two species of S. bongori and S. enterica, the most prevalent pathogens in the food industry and the causative agent in several foodborne outbreaks [29, 30]. Salmonella enterica is commonly associated with refrigerated poultry products stored on shelves during food processing or in supermarkets. Three various types of Salmonella are important for human health, including non-typhoid Salmonella, S. typhi and S. paratyphi. Fresh poultry and meat are highly prone due to their nutrient-rich content, high water activity and near-neutral pH (5.5–6.5), creating optimal environmental conditions for Salmonella spp., which are not spore-formers and can easily be destroyed by heat at 60 °C for 15–20 min. Furthermore, growth of most isolates was inhibited below 7 °C and pH 4.5, while nontyphoidal salmonellosis in the US is nearly 1.35 million illnesses per year [31]. Because many people reside in Saudi Arabia during haj and umrah seasons, a significant prevalence of Salmonella infection occurs [32]. Pseudomonas aeruginosa is wide spread on meat surfaces and in low-acid dairy products and affecting more than 2 million individuals and killing roughly 90,000 of them annually [33]. Because of its adaptability, P. aeruginosa may grow at temperatures lower than 7°C and contaminate fresh meat sold in stores, causing its spoilage via lipolytic, saccharolytic and proteolytic processes [34]. In addition, the microorganism secretes extracellular enzymes that cause breakdown of foods and includes a high degree of medication resistance, which can result in serious acute and chronic infections in immunocompromised people. Human infections usually affect the respiratory tract (RT), soft tissues, blood vessels, urinary tract (UT) and wounds [35]. Carbapenem-resistant strains of P. aeruginosa pose a hazard to public health [36]. Due to the abundance of EPS, cells can adhere to stainless-steel surfaces and create biofilms alone or with other pathogens and produce multispecies biofilms, increasing their stability and resistance [37].
1.5.2 Gram-positive bacteria
Listeria monocytogenes is a rod-shaped, non-spore-forming, facultative-anaerobic Gram-positive bacterium. It causes human infections of listeriosis, a serious illness that includes septicemia and meningitis, particularly in immunocompromised individuals and is capable of growing at temperatures ranging 3–45 °C with the optimal temperature of 30–37 °C [38]. Listeria monocytogenes is a harmful foodborne microorganism that is killed by pasteurization. Consumption of dairy products, meats, fishes, fruits, soft cheeses, ice creams and poultries has been linked to listeriosis epidemics [39]. It can form biofilms on surfaces commonly detected in the food industry and is resistant to treatments with heat up to 60 °C [40]. It can thrive in a broad range of conditions, including high salinities (10%), cold temperatures (4 °C), low water activities (< 0.9) and wide pH ranges (4.1–9.6) [41]. Post-processing contamination with Listeria spp. may be resulted from inadequate cleaning and poor separation techniques between ready-to-eat and raw foods [42]. In addition, L. monocytogenes is one of the most significant pathogenic microorganisms due to its high mortality rates (15.6%) and one of the major causes of hospitalizations and deaths in the US [43].
Staphylococcus aureus is responsible for staphylococcal food poisoning (SFP) and produces enterotoxins within the temperature range of 10–46 °C. Staphylococcus genus includes more than 50 recognized species; of which, S. aureus is commonly detected in food products and reaches foods through raw materials and grows best on meat, poultry and egg products. In food production chain, it may develop biofilms on living and non-living surfaces, resist desiccation and thrive on a variety of surfaces. Furthermore, strains of S. aureus that produce enterotoxins have been identified in a variety of food samples. [44]. Other Gram-positive bacteria such as Brochothrix thermosphacta and Carnobacterium spp. can form biofilms in the meat-processing environment [45].
1.6 Strategies for Controlling Biofilm Formation in the Food Industry
Pathogenic bacteria that form biofilms create strong defenses against antibiotics and are difficult to treat. Removing these biofilms is a critical challenge due to the severe effects on public health [46, 47]. Chemical and physical methods have been used to inhibit bacterial biofilms in the food industry. Chemical treatments can help; however, mechanical treatments such as clean-in-place are not effective. The most reliable way to prevent bacterial biofilm growth is through aseptic processing, routine disinfection and equipment sterilization. Various disinfectants and novel biofilm elimination methods of the food industry are briefly summarized (Figure 2).
1.6.1 Chemical and Physical Treatments
Biofilms can be treated with concentration and time-dependent chemical sanitizers. Decreasing bacterial populations to human-safe levels is the goal of sanitation. Sanitizing food-processing equipment is necessary to avoid cross-contamination between batches of foods. Stages of general cleaning methods for places that handle and manufacture foods include physical pre-cleaning, detergent washing, rinsing, sanitation, final rinsing and drying. Spraying detergents in form of foam or aerosol spray is possible as long as the right doses and time are used for surface contact. Alkaline and acidic chemicals are widely used as detergents in the food industry. A majority of disinfectants are safe to use on non-food-contact surfaces; nevertheless, food-contact and occasionally non-contact surfaces should be rinsed with high-quality water. The most popular sanitizer in the food industry is aqueous ClO2, which acts well against B. cereus endospores in biofilms on steel surfaces [48]. In the food industry, chlorine-based sanitizers are most frequently used; nevertheless, several microorganisms have developed resistance to chlorine treatments. Food factories frequently use sodium hypochlorite or NaOCl [49]. Moreover, hydrogen peroxide (H2O2) and NaClO were successful in removing biofilms of S. aureus and P. aeruginosa; however, aqueous ClO2 was more effective than NaOCl in eliminating E. coli O157:H7 biofilms [50]. In the food industry, H2O2 is a powerful oxidizing disinfectant that is often used. When it is exposed to biofilms, H2O2 produces free radicals that kill the bacteria at concentrations of 0.08–5%, without harmful side effects. Quaternary ammonium compounds are frequently used as sanitizers, removing biofilms and leading to bacterial lysis [51]. Steam heat treatment is a method used to decrease number of harmful bacteria and biofilm populations in production areas [52]. Non-thermal plasma is a partially ionized gas with low temperature and promising antibacterial characteristics. It can destroy bacterial biofilms of Pseudomonas spp., S. enterica and Bacillus spp. Ozone breaks down the cellular envelopes of a variety of microorganisms, including viruses, bacterial biofilms and protozoans.
1.6.2 Elimination of Biofilms Using Biological Strategies
In recent years, a more efficient and ecologically friendly control method for the elimination of or managing growth of dangerous biofilms is use of enzymes, bacteriophages, bacteriocin and plant extracts, which have been discussed based on safe and green approaches to control pathogen biofilm formation.
1.6.2.1 Enzyme against bacterial Biofilm
Enzymes or proteins are biologically active macromolecules against biofilm formation since proteases or other degrading enzymes have shown the ability to inhibit biofilm formation [53]. Enzymes are detected to include therapeutic functions in removal of pathogenic biofilms and can widely be used in detergents of food industries. In recent times, a variety of enzymes enriched products have been commercialized that include tablets, rinsing solutions, chewing gums for dental treatments and denitrifies containing enzymes such as lysins, dextranase, mutants that can serve to play an effective role in disintegration of the biofilm matrix [54]. The most often used enzyme types vary depending on the makeup of the biofilm as proteases, cellulases, polysaccharide depolymerases, alginate lyases and dispersin B [55]. Proteinase K and lysozyme have been verified to include promising antibiofilm activities [56]. The α-amylase enzyme includes potential to operate as an antibiofilm agent against bacterial species that produce biofilms, including S. aureus and P. aeruginosa [57]. Protease formulations were effective in eliminating S. aureus biofilms from polystyrene surfaces; however, combinations of protease, amylase and cellulase were needed to eradicate biofilms of P. aeruginosa. Cellulase effectively inhibited biomass and microcolony formation by P. aeruginosa on glass surfaces in partial [58].
1.6.2.2. Bacteriophages against Biofilm
Bacteriophages (phages) are bacterial viruses, acknowledged as the most diverse and abundant entities. Bacteriophages are mostly used in primary production to ensure food safety, biosanitization and biopreservation [59]. Phages can break down biofilms spread through developed biofilms and then show their antimicrobial characteristics inside them. Phage treatments are injected directly into food products during the biopreservation processes to extend the food shelf life and used in biosanitization to avoid biofilms on equipment surfaces [60]. Bacteriophages can create enzymes that break down the biofilm structure and presence of phage receptor sites such as endolysins and depolymerases. Use of phages as biocontrol agents in foods is affected by various factors, including the food matrix, surface area and structure, bacterial species, inhibitory compound and phage dose [61]. A commercial product, LISTEXTM, has been developed from the bacteriophage P100, which uses an enzymatic process to cause cell lysis and EPS breakdown. The US Department of Agriculture (USDA) has approved use of this natural, non-toxic phage product. It is effective against L. monocytogenes. Additionally, it seems that L. monocytogenes biofilms are susceptible to phage biocontrol. Phage Guard Listex, which uses phage P100, effectively removes biofilms from stainless steel surfaces. A user of Listeria phage P100 (under the commercial name of Listex P100) is a biological agent, formed to remove the biofilms in processed meat products [62]. In addition, a phage cocktail was used for 1 h to destroy and decrease pathogen populations of E. coli O157:H7 on stainless steels, ceramic tiles and high-density polyethylene coupons [63]. Endolysin is the second kind of enzyme produced by phages that include potential uses for sanitization. During the final stage of their lytic cycle, they release progeny of virions through the breakdown of the cell wall, which were active against Gram-positive bacteria [64]. Depolymerases are types of enzyme that may prevent production of biofilms and break down capsular polysaccharides in Gram-negative bacteria [65].
1.6.2.3 Bacteriocins against biofilms
Lactic acid bacteria (LAB) are used to produce fermented foods and the most important genera in controlling spoilage and pathogenic microbes are Lactobacillus and Bifidobacterium due to the production of bacteriocins and acids. Bacteriocins from LAB are used as alternatives to chemical food preservatives. They can spread through cell membranes and release internal components such as K+ and inorganic phosphate or they can prevent production of proteins, RNA and DNA [66]. Due to its safety in the gastrointestinal system, bacteriocin has extensively been
Assessment of the Phytochemical Profile, Free Radical Scavenging and Antibacterial Effects of Pilea symmeria from Mizoram, India: Therapeutic properties of Pilea symmeria
No full textAntibacterial and free radical scavenging properties of Pilea symmeria, a traditional medicinal plant from Mizoram, India, have been examined in this study. Chloroform, ethanol, and aqueous were used to extract the plant components. Extracts were phytochemically analyzed qualitatively and quantitatively. The extracted sample were tested for their ability to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3- ethylbenzothiazoline-6-sulfonic acid) ABTS, and superoxide anion (O2•(-)) radicals. An antibacterial susceptibility test was performed against the bacterial strain Escherichia. coli, Bacillus subtilis and Klebsiella pneumoniae using disc diffusion method. The broth microdilution method determined the minimum inhibitory concentration (MIC). Plating samples from a well of MIC and above concentrations on a new agar plate determined minimum bactericidal concentration (MBC). Various phytochemicals, including terpenoids, tannins, flavonoids, cardiac glycosides, steroids, alkaloids, saponins, and phlobatannins, were present in the various extracts of P. symmeria. Phytochemical analysis by LC-MS revealed the presence of 34 major compounds having various biological activities. The most potent radical scavenger was ethanol extract, which contains the highest overall phenolic and flavonoid content with the lowest IC50 value. The various extracts also suppressed the tested organisms' growth in a concentration-dependent manner. Therefore, our results suggested that P. symmeria extracts contain various phytochemicals with anti-radical and anti-bacterial activities and can potentially develop into novel phytomedicines
Magnesium Phosphate Cements for Endodontic Applications: A Critical Review of Promise and Pitfalls
Get PDFMagnesium phosphate cements (MPCs) have recently gained attention as potential materials for endodontic applications due to their rapid setting, favourable mechanical properties, and bioactive potential. Laboratory and preclinical studies indicate that MPCs can form apatite-like structures, exhibit good compressive strength, and support cell viability, suggesting promising biological interactions. However, several limitations remain unresolved. The acid–base setting reaction of MPCs is strongly exothermic, which may pose a risk to pulp or periapical tissues, and ammonium-containing formulations can release cytotoxic ammonia, although partial mitigation is possible through sodium phosphate substitution. Rapid setting enhances handling in controlled conditions but may complicate placement in complex root canal anatomies. While in vitro studies suggest comparable or superior sealing ability relative to conventional calcium silicate cements, human clinical evidence is minimal or absent. Degradation and resorption profiles of MPCs may further affect their suitability as scaffolds in regenerative endodontics. Overall, MPCs represent promising investigational materials, yet claims regarding clinical readiness are premature. Careful evaluation of their physicochemical behaviour, biological safety, and practical handling is essential before consideration for routine clinical use
Precision Immunotherapy for NSCLC: Multi-epitope Peptide Vaccine Targeting VEGF-A, TGF-β and MAGE-A3 Increases Antitumor Key Cytokine Balance
Get PDFIntroduction: Lung cancer remains the leading cause of cancer-related mortality worldwide, underscoring the urgent need for advancements in treatment options. Although, current standard interventions, including surgery, radiotherapy and chemotherapy are widely employed, a significant number of patients experience relapses, highlighting the critical demand for innovative therapeutic strategies. This study was conducted to develop and evaluate a novel multi-epitope peptide vaccine designed from VEGF-A, TGF-β and MAGE-A3 markers, with the aim of enhancing therapeutic efficacy. Lung cancer remains the leading cause of cancer-related mortality worldwide, underscoring the pressing need for more effective therapeutic interventions. Although current standard treatments—including surgery, radiotherapy, and chemotherapy—are widely utilized, a substantial proportion of patients experience disease recurrence, highlighting the necessity for innovative therapeutic strategies. In this study, we developed and evaluated a novel multi-epitope peptide vaccine constructed from VEGF-A, TGF-β, and MAGE-A3 markers, with the objective of enhancing therapeutic efficacy.
Materials and Methods: Optimal epitopes from VEGF-A, TGF-β, and MAGE-A3 were systematically identified and selected, and subsequently conjugated using a KKK linker to form the final multi-epitope vaccine construct. Two groups of BALB/c mice were immunized with the peptide at concentrations of 10 mg/mL and 100 mg/mL, following an immunization protocol that included three weekly administrations. In the fourth week, spleen tissue was collected from the mice to assess the expression levels of IFN-γ, IL-4, IL-6, TNF-α, and IL-10 cytokine genes, thereby enabling a comprehensive evaluation of the immunogenic and functional efficacy of the peptide vaccine.
Results: Bioinformatics evaluations have revealed a promising multi-epitope peptide vaccine,SVRGKGKGQKRKRKKSKKKHHMVKISGGPHISYPPKKKRLESQQTNRRKKRALD.
This peptide notably enhances the expression of key cytokine genes, including TNF-α, IL-6, IFN-γ, IL-4 and IL-10 among the group that received the vaccine at a dose of 10. Even more pronounced levels of gene expression were observed at the higher dose of 100.
Conclusion: This multi-epitope peptide demonstrates considerable potential to elicit a robust immune response and effectively target cancer cells. We strongly recommend conducting further supplementary tests to evaluate its efficacy and possible side effects
Multidrug resistance patterns among clinical isolates of Acinetobacter baumannii from Imam Khomeini Hospital, Tehran
No full textBackground and Objectives
Acinetobacter baumannii has emerged as one of the most significant opportunistic pathogens in hospital environments due to its remarkable ability to acquire and disseminate antibiotic resistance genes. It is a major cause of healthcare-associated infections, particularly in intensive care units (ICUs), leading to ventilator-associated pneumonia, wound infections, and septicemia. The present study aimed to investigate the antibiotic resistance patterns of clinical A. baumannii isolates and to assess the prevalence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) phenotypes among them.
Materials and Methods
In this descriptive-analytical study, several clinical isolates of A. baumannii, categorized into ABI and ABH groups, were collected from hospitalized patients in a tertiary-care hospital. Bacterial identification was performed using standard biochemical and molecular methods. Antimicrobial susceptibility testing was conducted by the disk diffusion (Kirby–Bauer) method in accordance with CLSI guidelines.
Results
Antibiogram results showed that more than 50% of the isolates were resistant to imipenem and meropenem, while high levels of resistance were also observed to cephalosporins and fluoroquinolones. Colistin remained the most effective antibiotic, with only a small percentage of isolates showing resistance. Comparative analysis showed that isolates from the (ABI) group showed a broader resistance profile than isolates from the (ABH) group. Overall, 92% of the isolates were classified as multidrug-resistant (MDR) and 47% as extensively resistant (XDR).
Discussion
Implementation of rigorous antibiotic stewardship programs and continuous resistance surveillance are urgently needed to prevent the dissemination of MDR and XDR A. baumannii strains in clinical settings.
Conclusion
The findings of this study demonstrate an alarming prevalence of antibiotic resistance among A. baumannii isolates in the hospital environment, posing a serious threat to infection control and patient safety
Er:YAG Laser Versus Conventional Surface Treatment of Lithium Disilicate: In Vitro Study: Er:YAG Laser as surface treatment in lithium disilicate
No full textIntroduction: The high-power 2940 nm Er:YAG (erbium-doped yttrium aluminium garnet) laser increases the rough surface of lithium disilicate, increasing the bonding strength of ceramics when they are bonded to the tooth using resin matrix cement. This investigation aimed to compare the Er:YAG laser with the conventional surface treatment of lithium disilicate.
Methods: In this study, 50 lithium disilicate discs (5 mm diameter×2 mm thickness) were divided into five groups (n=10): Control group (CG) (10% hydrofluoric acid followed by 37% phosphoric acid), Group 1 (G1) (ER:YAG laser energy of 300 mJ/50 µs), Group 2 (G2) (Er:YAG laser energy of 400 mJ/50 µs), Group 3 (G3) (Er:YAG laser energy of 500 mJ/50 µs), and Group 4 (G4) (10% hydrofluoric acid, Er:YAG laser energy of 500 mJ/50 µs). After completing the surface treatments, 6 mm high Tygon was fixed and filled with self-adhesive dual resin cement (SET PP SDI Limited, Victoria, Australia). The samples were stored for 24 hours and subjected to shear tests until structural failure.
Results: ANOVA analysis found no statistically significant difference between the groups analyzed (P=0.0689). G2 had the highest bond strength with 12.6±3.2 MPa, while G1 had the lowest with 9.5±2.2 MPa, followed by the CG 9.8±3.2. It was observed that with higher laser irradiation power, the adhesive strength decreased, as evidenced in G3 with 11.6±1.9 MPa.
Conclusion: The radiation power of 400 mJ, frequency of 20 Hz, and pulse duration of 50 µs improved the bond strength between lithium disilicate and dual resin cement. However, the group that obtained the lowest strength was Group 3, with a laser energy of 500 mJ/50 µs, generating highly expulsive zones in lithium disilicate
Insights into Astrogliosis, Inflammation Processes, and Emerging Treatments by Exosome Therapy and LowLevel Laser Therapy for Spinal Cord Injury: A Systematic Review: Exosome therapy and low-level laser therapy for spinal cord injury
No full textIntroduction: Spinal cord injury (SCI) is among the most severe medical conditions, with profound impacts on global healthcare systems. SCI results in temporary or permanent loss of spinal cord function and is associated with high incidence rates, substantial economic burden, significant disability, and a low average age of onset. Astrogliosis and neuroinflammation play central roles in secondary injury and limit functional recovery. This systematic review examines pathophysiology, mechanisms of recovery, and emerging clinical treatment strategies for SCI.
Methods: A comprehensive literature search was conducted across multiple databases, including PubMed, Scopus, and Web of Science, to identify relevant studies on SCI classification, pathophysiology, and treatment approaches, with a particular focus on Exosome and low level Laser therapy. The search included articles published up to September 2024, and key data were extracted for analysis.
Results: A total of 141 studies met the inclusion criteria. The pathogenesis of SCI involves an initial mechanical injury followed by a secondary cascade of molecular and cellular events that exacerbate tissue damage. Current treatment options primarily provide supportive care for patients with lifelong disabilities. Pharmacological interventions focus on neuroprotection, employing medications and therapeutic agents tailored to modulate degenerative processes. Non-pharmacological approaches, including growth factors, Low level laser therapy, cultured cells, and vitamins, offer additional therapeutic benefits. Laser therapy integration into SCI treatment is increasingly studied due to its anti‑inflammatory, neuroprotective, and analgesic effects. Exosome therapies have shown significant neuroprotective and neuroregenerative potential by addressing multiple pathological mechanisms in SCI.
Conclusion: A promising future direction lies in combining conventional pharmacological and surgical strategies with emerging therapies, particularly exosome therapy and LLLT, offers a promising approach to mitigate secondary injury, modulate astrogliosis, and enhance recovery in SCI patients. Comprehensive therapeutic strategies integrating pharmacological and nonpharmacological approaches with cutting-edge cell therapies hold significant promise for improving outcomes in SCI treatment
Evaluation of Vibradiofotology Technology using the ERECTOFIX Device in the Treatment of Erectile Dysfunction: A Randomized Controlled Double-Blind Pilot Study: Evaluation of vibradiofotology technology in erectile dysfunction treatment
No full textIntroduction: Over the past decade, energy-based therapies have been introduced as noninvasive and restorative treatment modalities for erectile dysfunction. Furthermore, previous studies have shown the efficacy of penile vibratory stimulation and photobiomodulation in treating erectile dysfunction. Integrating these therapeutic approaches, which are employed simultaneously in the Vibradiofotology technology, may lead to achieving better outcomes in the treatment of erectile dysfunction. This study aims to evaluate the efficacy of Vibradiofotology technology delivered via the Erectofix device in patients with erectile dysfunction.
Methods: In this randomized clinical trial, fifty-five patients diagnosed with erectile dysfunction were included. The patients were assigned to either the control group or the intervention group. In the intervention group, the patients received treatment with the Erectofix device for five sessions. Each session lasted 45 minutes and was administered once a week. Meanwhile, the control group received oral medication along with sham laser treatment.
Results: Among the fifty-five patients included in the study, 27 were assigned to the intervention group and 28 to the control group. The intervention group showed a significant improvement in each domain of the IIEF score compared to the control group. The erectile function showed a significantly greater increase in IIEF scores in the intervention group (19.59±5.57) compared to the control group (7.39±2.23; P<0.001). Furthermore, significant improvements were observed in orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction in the intervention group.
Conclusion: Vibradiofotology technology, which integrates different therapeutic approaches, may be a safe treatment option for erectile dysfunction. Improvements in IIEF scores, patients’ overall satisfaction, and erectile function can be promising in the efficacy of this modality. Nevertheless, due to the limitations of the present study, further research is required to investigate the potential benefits of this novel modality in improving patients’ quality of life
Correction to: Therapeutic Effects of Combination Therapy and Photobiomodulation Therapy on Retinal Regeneration: Correction
Get PDFIn the article titled “Therapeutic Effects of Combination Therapy and Photobiomodulation
Therapy on Retinal Regeneration” published in J Lasers Med Sci 2022;13:e36 (doi: 10.34172/jlms.2022.36), there was an error in the Ethical approval section.The ethics approval code was incorrectly reported as:“All protocols were confirmed by the Ethics Committee of Shahid Beheshti University of Medical Sciences (IR.SBMU.RETECH.REC.1400.008).”The correct ethics approval code is:IR.SBMU.REC.1400.008The corrected sentence should read:“ All protocols were confirmed by the Ethics Committee of Shahid Beheshti University of Medical Sciences (IR.SBMU.REC.1400.008 )