Prophylaxis Research Articles

Efficacy Analysis of Bronchial Arterial Chemoembolization for Nonsmall Cell Lung Cancer: A Systematic Review and Meta-Analysis.

Objective: This study aims to comprehensively evaluate the efficacy and safety of bronchial arterial chemoembolization (BACE) in the treatment of advanced nonsmall cell lung cancer (NSCLC) through a meta-analysis of single-group rate, providing evidence-based guidance for clinical treatment. Materials and Methods: A systematic search was conducted in PubMed, the Cochrane Library, Embase, and Web of Science databases for relevant studies up to January 15, 2024. Inclusion criteria encompassed single-arm or multi-arm studies of nonrandomized controlled trials, observational studies, and single-arm studies in English language, focusing on NSCLC patients treated with BACE. Data extraction, quality assessment, and statistical analysis were performed following predefined protocols. Results: In total, 172 articles were initially retrieved, with 11 studies meeting the inclusion criteria. The included studies comprised 510 patients. Meta-analysis revealed significant heterogeneity among studies for median progression-free survival (PFS), median overall survival (OS), objective response rate, and disease control rate. The combined median PFS was 6.87 months (95% confidence interval [CI] 5.30-8.44), and the combined median OS was 13.68 months (95% CI 10.69-16.67). Subgroup analysis based on intervention measures demonstrated varying efficacy outcomes. Adverse reactions associated with BACE were generally mild, with no reports of grade 3 or higher adverse events. Conclusion: BACE emerges as a promising treatment modality for advanced NSCLC, exhibiting favorable efficacy and safety profiles.

CTNI-35. EVALUATE THE SAFETY AND PRELIMINARY EFFICACY OF THE COMBINATION OF NAVIFUS SYSTEM WITH RE-IRRADIATION FOR RGBM PATIENTS

Abstract The blood-brain barrier (BBB) remains the major obstacle in treating patients with malignant brain tumors. Radiation therapy (RT) is the mainstay adjuvant modality regardless of the BBB, but its effectiveness is hindered by the hypoxic microenvironment. Focused ultrasound (FUS) combined with systemic microbubbles has been shown to open the BBB and potentially increase regional perfusion. However, no clinical study has investigated the combination of RT with FUS-BBB opening (RT-FUS). Here, we report an interim analysis of an ongoing single-arm, prospective, pilot study (NCT04988750) combining RT-FUS for recurrent malignant high-grade glioma patients, where re-RT was considered for disease control. FUS-BBB opening was conducted within 2 hours before RT. Treatment responses were evaluated by objective response rate (ORR) using magnetic resonance imaging, progression-free survival, overall survival, and adverse events (AEs). In this pilot clinical trial, an interim analysis of six recurrent malignant high-grade glioma patients who underwent a total of 24 RT-FUS treatments was presented. Three patients experienced rapid disease progression after RT-FUS, while the other three patients had at least stable disease after RT-FUS, with or without salvage chemotherapy or targeted therapy. There were no FUS-related AEs, but re-RT-related grade three radiation necrosis was observed. The interim analysis of this ongoing clinical trial showed that the combination of RT-FUS was safe, with no FUS-related adverse effects. Two more cases will be recruited in this trial. A comprehensive analysis of radiation dosimetry and FUS energy distribution is expected after completing the final recruitment.

A ATUAÇÃO DO FISIOTERAPEUTA NA SAUDE DO IDOSO HIPERTENSO

According to the WHO, in 2050 the number of elderly people aged 60 and over will exceed the number of total children aged zero to 14 years old. Arterial hypertension (technical term) or high blood pressure (term used by the lay public) is a chronic disease that often affects elderly people, characterized by high levels of blood pressure in the arteries. It occurs when the maximum and minimum pressure values are equal to or exceed 140/90 mmHg (or 14 by 9) The objective of the Physiotherapy professional is to assist in the prevention of diseases or mainly in the care of patients with SAH, promoting quality of life, independence and improving the daily life of the elderly. Care needs to be provided or better applied so that this high population population follows a path where morbidity and mortality do not increase as a result of the health of the elderly.

Use of Encapsulated Polyphenolic Compounds in Health Promotion and Disease Prevention: Challenges and Opportunities

Plant-derived phenolic compounds are recognized to provide several health benefits for humans, including anticancer, anti-inflammatory, and antioxidant proprieties. Their bioavailability in the human body has a significant impact on these outcomes. Their bioaccessibility and bioavailability are highly dependent on the structure and manner in which phenolics enter into the organism, through a complex food matrix, for instance, or as pure isolates. Furthermore, the bioaccessibility of phenolic compounds in the body is greatly impacted by interactions with a broad range of other macromolecules (such as proteins, lipids, dietary fibers, and polysaccharides) in food or during digestion. Encapsulation is a process that can improve bioaccessibility and bioavailability by guaranteeing coating of the active ingredients, controlled release, and targeted distribution to specific parts of the digestive system. However, this field has not yet received enough attention, due to the complex mechanisms through which phenolics act in the body. This review attempts to shed light on the results of research that has been performed on the potential and therapeutic benefits of encapsulated polyphenols in both health and disease.

The possibilities of using ursodeoxycholic acid in the practice of a gastroenterologist and therapist

Relevance. Ursodeoxycholic acid (UDCA) is a natural hydrophilic bile acid, which initially found its use in the treatment of a number of liver diseases as a first–line therapy. UDCA reduces the secretion of cholesterol into bile and is actively used in the treatment and prevention of gallstone disease; UDCA also has the ability to stimulate hepatobiliary secretion, which is important for patients with primary biliary cholangitis and primary sclerosing cholangitis. More recent studies have shown the pleiotropy of the effects of UDCA, in terms of effects on pathophysiological processes in the liver and the entire hepatobiliary complex, for example, anti-inflammatory and antifibrotic effects, immunomodulatory and anticarcinogenic effects. Even more interesting and important were the complex mechanisms of the effect of UDCA on the development and progression of non-alcoholic fatty liver disease (NAFLD) and, further, on the pathogenetic relationships of NAFLD and cardio-vascular pathology. The article examines the possibilities of using UDCA in diseases of the gastrointestinal tract and, more broadly, the possibilities of the drug in influencing NAFLD and the development and progression of cardiovascular and metabolic diseases.

Benefits of Camel Milk over Cow and Goat Milk for Infant and Adult Health in Fighting Chronic Diseases: A Review

The nutritional composition, antimicrobial properties, and health benefits of camel milk (CAM), cow milk (COM), and goat milk (GOM) have been extensively studied for their roles in managing diabetes and cardiovascular diseases (CVD). This review compares these milk types’ nutritional and therapeutic properties, emphasizing their applications in chronic disease management. CAM is rich in insulin-like proteins, vitamins, minerals, and bioactive compounds that benefit glycemic control and cardiovascular health. It also exhibits potent antioxidants, anti-inflammatory, and lipid-lowering effects, which are crucial for managing diabetes and reducing CVD risk factors. While COM and GOM provide essential nutrients, their impact on metabolic health differs. GOM is known for its digestibility and antihypertensive properties, whereas COM’s higher lactose content may be less suitable for diabetic patients. CAM’s unique nutritional profile offers distinct therapeutic benefits, particularly for diabetes and CVD management. Further research is needed to clarify its mechanisms of action and optimize its clinical application for chronic disease prevention and management.

Perforated plate ventilation system and dynamics of infectious respiratory particle transmission

AbstractWith the removal of indoor pollutants and the assurance of air quality emerging as critical research topics, the optimization of the internal environment in offices, where people stay for extended periods, is essential for controlling the spread of infectious respiratory particles. Frequent movements of personnel and the operation of doors and windows within offices significantly impact the mechanisms of droplet transmission, warranting further investigation. This study employs computational fluid dynamics simulations to explore the droplet dispersion characteristics and pollutant removal efficiency of the simplified model of perforated plate ventilation system (PPVS) (the diameter of the air supply openings has been reasonably simplified and uniformly set to 0.02 m) in office settings, as well as the impact of dynamic door operation scenarios on droplet spread and concentrations in breathing zones. To optimize the ventilation system's pollutant removal efficiency, airflow velocities (2.86, 3.18, and 5.00 m/s) are varied, with simulations conducted at the optimal velocity of 3.18 m/s. The effects of continuous door operations, door‐opening directions (towards the office and towards the isolation room), and opening speeds (π/4, π/6, π/8, and π/10 rad/s) are also examined, revealing significant impacts on droplet spread. Results indicate that PPVS effectively reduces indoor pollutant concentrations at all tested airflow velocities, with the optimal speed identified as 3.18 m/s. Additionally, door‐opening direction and speed can significantly influence droplet spread. Opening doors towards isolation rooms at smaller angles (less than 30°) effectively reduces droplet concentrations in personnel breathing zones, thereby mitigating the risk of droplet transmission. Faster door‐opening speeds also contribute to lower droplet concentrations in these zones. This innovative study explores the impacts of PPVS and dynamic door operation dynamics on droplet transmission during respiratory disease outbreaks, providing valuable theoretical insights and technical support for disease prevention and indoor air quality improvement.

Impact of salmon farming in the antibiotic resistance and structure of marine bacterial communities from surface seawater of a northern Patagonian area of Chile

BackgroundAquaculture and salmon farming can cause environmental problems due to the pollution of the surrounding waters with nutrients, solid wastes and chemicals, such as antibiotics, which are used for disease control in the aquaculture facilities. Increasing antibiotic resistance in human-impacted environments, such as coastal waters with aquaculture activity, is linked to the widespread use of antibiotics, even at sub-lethal concentrations. In Chile, the world's second largest producer of salmon, aquaculture is considered the primary source of antibiotics residues in the coastal waters of northern Patagonia. Here, we evaluated whether the structure and diversity of marine bacterial community, the richness of antibiotic resistance bacteria and the frequency of antibiotic resistance genes increase in communities from the surface seawater of an area with salmon farming activities, in comparison with communities from an area without major anthropogenic disturbance.ResultsThe taxonomic structure of bacterial community was significantly different between areas with and without aquaculture production. Growth of the culturable fraction under controlled laboratory conditions showed that, in comparison with the undisturbed area, the bacterial community from salmon farms displayed a higher frequency of colonies resistant to the antibiotics used by the salmon industry. A higher adaptation to antibiotics was revealed by a greater proportion of multi-resistant bacteria isolated from the surface seawater of the salmon farming area. Furthermore, metagenomics data revealed a significant higher abundance of antibiotic resistant genes conferring resistance to 11 antibiotic families in the community from salmon farms, indicating that the proportion of bacteria carrying the resistance determinants was overall higher in salmon farms than in the undisturbed site.ConclusionsOur results revealed an association between bacterial communities and antibiotic resistance from surface seawater of a coastal area of Chile. Although the total bacterial community may appear comparable between sites, the cultivation technique allowed to expose a higher prevalence of antibiotic resistant bacteria in the salmon farming area. Moreover, we demonstrated that metagenomics (culture-independent) and phenotypic (culture-dependent) methods are complementary to evaluate the bacterial communities’ risk for antibiotic resistance, and that a human—influenced environment (such as salmon farms) can potentiate bacteria to adapt to environmental stresses, such as antibiotics.

PROMOÇÃO DA SAÚDE E BEM-ESTAR EM IDOSOS ATRAVÉS DE PROGRAMAS DE EXERCICIOS FUNCIONAL: UMA REVISÃO INTEGRATIVA

This study presents an integrative review on the benefits of functional exercises for elderly health and well-being. With the global aging population and associated public health challenges, it is crucial to explore practices that enhance quality of life (SILVA; SANTOS, 2019). The research analyzed studies that highlight how functional training aids in maintaining physical fitness, autonomy, and disease prevention. Observed benefits include improvements in physical abilities, such as strength and balance, and cognitive function (ALMEIDA; CARDOSO, 2022), as well as a positive impact on social interaction and psychological well-being among the elderly (FREITAS; ALMEIDA, 2021). The study also discusses adapting exercise programs to meet individual needs, considering factors like health conditions and reduced mobility (RODRIGUES; LIMA, 2023)

AGRIBUSINESS STRATEGIES FOR MITIGATING RISKS IN THE TOMATO VALUE-CHAIN: FROM SOKOTO FIELDS TO MARKETS

This study examined the risks, attitudes, and management strategies of 100 tomato value chain actors (45 farmers and 55 marketers) aged 30-60 years in Sokoto Metropolis, Nigeria. A multi-stage sampling technique was employed to select respondents An interview schedule was used for the data collection, while descriptive statistics were used to analyze the data. The socioeconomic results reveal that all the respondents were male, mostly middle-aged (mean of 42 years), married. About 72% of the marketers are members of cooperative associations while none of the farmers were members. About 67% of the farmers and 33% of the marketers have a secondary occupation. Results revealed that farmers predominantly encountered pests and diseases infestation (mean score 5.00), yield variability (mean score 4.69), and price instability (mean score 4.69) as major risks. Marketers, on the other hand, cited perishability (mean score 4.98), price instability (mean score 4.96), and payment defaults (mean score 4.84) as critical challenges. While pest and disease control, crop diversification, and income diversification were common among farmers, marketers primarily relied on price negotiation, improved storage, and efficient transportation. The study concludes that enhancing extension services, promoting cooperatives, and improving infrastructure are crucial to mitigating risks and boosting the tomato value chain's sustainability in Sokoto.

The Role of Iron in Atherosclerosis and its Association with Related Diseases.

This review aims to elucidate the multifaceted role of iron in the pathogenesis of atherosclerosis. The primary objective is to summarize recent advances in understanding how iron contributes to atherosclerosis through various cellular mechanisms. Additionally, the review explores the therapeutic implications of targeting iron metabolism in the prevention and treatment of cardiovascular diseases. A growing body of literature suggests that excess iron accelerates the progression of atherosclerosis, with the deleterious form of iron, non-transferrin-bound iron (NTBI), particularly exacerbating this process. Furthermore, iron overload has been demonstrated to play a pivotal role in endothelial cells, vascular smooth muscle cells, and macrophages, contributing to plaque instability and disease progression by promoting lipid peroxidation, oxidative stress, inflammatory responses, and ferroptosis. Iron plays a complex role in atherosclerosis, influencing multiple cellular processes and promoting disease progression. By promoting oxidative stress, inflammation, and ferroptosis, iron exacerbates endothelial dysfunction, smooth muscle cell calcification, and the formation of macrophage-derived foam cells. Targeted therapies focusing on iron metabolism have proven effective in treating atherosclerosis and other cardiovascular diseases.

Evaluation of yield and stability of sugar beet (beta vulgaris L.) genotypes using GGE biplot and AMMI analysis

Rhizomania is the most destructive sugar beet disease in the world, and in recent years, it has widespread in most of the sugar beet growing areas in Iran. Since the control of this soil-borne disease is a difficult task, the use of resistant genotypes is known as the best measure against the disease. The ultimate goal of sugar beet breeders is to produce genotypes that can be used in both infected and non-infected fields without any reduction in terms of yield and quality. Twenty-one sugar beet genotypes along with four controls were evaluated in randomized complete block design with four replications in fields with natural infection to rhizomania in five research stations. Important sugar beet traits including root yield, sugar yield, sugar content, and white sugar yield were evaluated for two years (2021 and 2022). For all traits, location was the main source of variation that spanned 33 to 55% of the total sum of the square followed by the location×year×genotype accounted for 3–40% of the variation. Based on the results of analysis of variance, multivariate stability parameters were computed to evaluate the genotypes’ stability. The first two principal components (IPCA1 and IPCA2) generated by GGE biplot contributed for 31.3 and 17.5% difference in genotype×environment interaction for root yield, respectively. According to the GGE biplot, genotypes RM-11 and RM-12 were identified as the winning genotypes across environments for both root yield and white sugar yield traits whereas AMMI model identified RM-14 and RM-9 (for root yield) and RM-1 (for white sugar yield) as best genotypes. Based on the ideal genotype ranking, RM-11 and RM-10 were the best performer with a high mean yield as well as stability in the studied environments. The biplot rendered using the weighted average of absolute scores (WAASB) and root yield and white sugar yield identified RM-11 and RM-9 as superior genotypes in terms of yield and stability. The selected genotypes can be used in breeding programs to transfer the disease resistance and cultivar development.

The intersection of financial modeling and public health: A conceptual exploration of cost-effective healthcare delivery

This review paper explores the intersection of financial modeling and public health, highlighting the importance of cost-effective healthcare delivery in contemporary health systems. Financial modeling serves as a crucial tool for policymakers, providing evidence-based insights that inform decision-making and optimize resource allocation. Key financial models, including cost-benefit analysis and predictive modeling, are examined for their applications in public health initiatives, particularly in areas such as preventive care and chronic disease management. The paper discusses core public health priorities—prevention, access, and quality—and the economic constraints faced by healthcare systems. Recommendations are provided for policymakers and healthcare professionals to enhance the application of financial models, emphasizing the need for training, investment in data infrastructure, and fostering cross-sector collaborations. By leveraging financial modeling, public health systems can achieve improved health outcomes while maximizing resource efficiency, ultimately contributing to a more sustainable and equitable healthcare landscape.. Keywords: Financial Modeling, Public Health, Cost-Effectiveness, Healthcare Delivery, Resource Allocation, Preventive Care.

Sense of Community in the context of disease prevention and health promotion: A scoping review of the literature

BackgroundThe centrality of community engagement in disease prevention and health promotion interventions highlights the need to understand the contextual factors that shape participation. Sense of Community (SoC), characterized by feelings of belonging, connection, and interdependence among members of a community, has emerged as a key component of community capacity and is therefore expected to influence engagement outcomes. However, empirical evidence is needed to assess its actual impact on community engagement. Additionally, the literature lacks a broader synthesis of the role and implications of SoC in this context. This study aims to review the empirical literature on SoC in disease prevention and health promotion, with a special focus on its association with community engagement.MethodsA scoping review was conducted following the PRISMA guidelines, searching for empirical studies published between 1974 and 2023 via Scopus, Web of Science, and PubMed.ResultsNineteen studies were included in the review, revealing three key themes: (1) the community to which SoC refers – among intervention participants, within community coalitions, and defined by the place of residence; (2) the interpretation of SoC, either as a generic, intuitive concept or as a theoretically defined construct; (3) the ways in which SoC is studied – as a predictor of engagement but also as an outcome of the interventions. Generic SoC among intervention participants emerged as a positive outcome and a factor contributing to engagement. However, as the scope expanded to encompass broader communities and SoC became more theoretically grounded, these dynamics shifted. SoC related to the place of residence did not exhibit significant improvement after interventions. Broader community-level SoC showed positive associations with engagement among members of community coalitions, but evidence was less consistent among the individuals targeted by interventions.ConclusionsThe review highlighted a scarcity of empirical research on SoC despite its recognition as a key component of community capacity. Contextualizing SoC is crucial, as its interpretation significantly influences its role in disease prevention and health promotion interventions. Further research is needed to clarify whether SoC can foster engagement at all community levels, especially among the general population. This is particularly relevant amid the current context of escalating health needs and strained traditional resources, where community engagement is increasingly essential to ensuring the sustainable delivery of disease prevention and health promotion efforts. If SoC can drive widespread engagement, it could play a pivotal role in building more proactive and autonomous health-promoting communities.

The Role of Predictive Analytics in Disease Prevention : A Technical Overview

This article explores the transformative potential of predictive analytics in healthcare, focusing on its applications in disease prevention and public health management. It examines the power of data integration from diverse sources, the use of predictive modeling for risk stratification, and the broader implications for public health surveillance and chronic disease management. The article also discusses the significant growth of AI in the healthcare market and highlights successful implementations of predictive analytics across various medical domains. Additionally, it addresses the key challenges in implementing these technologies, including data privacy concerns, integration issues, model accuracy, and ethical considerations. Through numerous case studies and statistical evidence, the article demonstrates how predictive analytics is revolutionizing healthcare by enabling more accurate, personalized, and proactive approaches to disease prevention and management.

18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Large-Vessel Vasculitis During Active and Inactive Disease Stages Is Associated with the Metabolic Profile, but Not the Macrophage-Related Cytokines: A Proof-of-Concept Study

Giant cell arteritis (GCA) is an autoimmune/autoinflammatory disease affecting large vessels in patients over 50 years old. The disease presents as an acute inflammatory response with two phenotypes, cranial GCA and large-vessel vasculitis (LV)-GCA, involving the thoracic aorta and its branches. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET-CT) is among the imaging techniques contributing to diagnosing patients with systemic disease. However, its association with soluble inflammatory markers is still elusive. This proof-of-concept study aims to identify novel soluble serum biomarkers in PET/CT-positive patients with LV-GCA and associate them with active (0 months) and inactive disease (6 months following treatment), in sequential samples. The most-diseased-segment target-to-background ratio (TBRMDS) was calculated for 13 LV-GCA patients, while 14 cranial GCA and 14 Polymyalgia Rheumatica patients with negative initial PET/CT scans served as disease controls. Serum macrophage-related cytokines were evaluated by cytometric bead array (CBA). Finally, previously published NMR/metabolomics data acquired from the same blood sampling were analyzed along with PET/CT findings. TBRMDS was significantly increased in active versus inactive disease (3.32 vs. 2.65, p = 0.006). The analysis identified nine serum metabolites as more sensitive to change from the active to inactive state. Among them, choline levels were exclusively altered in the LV-GCA group but not in the disease controls. Cytokine levels were not associated with PET/CT activity. Combining CRP, ESR, and TBRMDS with choline levels, a composite index was generated to distinguish active and inactive LV-GCA (20.4 vs. 11.62, p = 0.001). These preliminary results could pave the way for more extensive studies integrating serum metabolomic parameters with PET/CT imaging data to extract sensitive composite disease indexes useful for everyday clinical practice.

Towards an AI-Driven Cyber-Physical System for Closed-Loop Control of Plant Diseases

Plant diseases are a major biosecurity threat to food production and the bio-energy industry. Early detection and control of plant diseases can improve producers’ profitability and reduce environmental impacts from chemical inputs. We proposed to develop a cyber-physical system with three major components: an AI-driven imaging system for early stress detection, an autonomous robotic system to collect plant samples, and a sequencing pipeline to detect molecular signatures of pathogens for disease confirmation. This system is envisioned to control a detected disease by removing or pruning infected plants. This manuscript describes the major milestones achieved by this CPS project and provides a future perspective on disease control automation in agriculture.

Perception of Health Professionals on Brain Drain in Nepalese Health Sector

Health workers are professionals who are engaged in the delivery of healthcare services to individuals. They include a wide range of roles such as doctors, nurses, midwives, paramedics, and support staff who provide clinical services to patients. They also encompass community health workers and public health professionals who work on disease prevention, health education, and improving access to healthcare. Health workers are essential for the functioning of health systems and play a critical role in ensuring the health and well-being of the population. Brain drain is increasing in Nepal day by day due to the many reasons, including the desire for better pay, work conditions, quality of life, high opportunities, more working hours, personal growth that make health workers leave. This situation is creating problem for Nepal’s health services. The main purpose of this study is to explore the perceptions of health professionals regarding brain drain in Nepal’s health sector. Through in-depth interviews and focused group discussions with various stakeholders, including doctors, nurses, pharmacist, health informatics, front line manager, the research aims to uncover the underlying factors contributing to emigration of skilled health workers. This study also examines the impact on Nepal’s healthcare system and suggest strategies to mitigate the loss of talent. This research contributes the deeper understanding of brain drain and provides insights for policy development to strengthen Nepal’s health sector.

Klrb1 Loss Promotes Chronic Hepatic Inflammation and Metabolic Dysregulation

Background/Objectives: CD161, encoded by the KLRB1 gene, is an inhibitory receptor expresses on various immune cell and has gained attention in immune checkpoint research. In recent studies, KLRB1 has been found to be one of the potential markers of liver diseases such as cirrhosis. Therefore, it will be important to understand what process KLRB1 involved in the liver for the prevention of liver diseases. Methods: We compared KO mice with wild-type controls by routine blood analysis and RNA-seq, and additionally performed H&E staining and qPCR to validate the differentially expressed genes (DEGs). Results:KO mice had fewer lymphocytes compared to the wild-type mice. A transcriptomic analysis showed that Klrb1 loss causes the upregulation of immune-related genes and pathways like NOD-like receptor and p53 signaling, while causing the downregulation of lipid metabolism-related genes. A protein interaction analysis indicated a potential cancer risk under chronic inflammation. Histological examination with H&E staining reveals an inflammatory response around the central venous vessels in the liver tissue of the KO mice. Conclusions: We conclude that Klrb1 knockout disrupts the immune and metabolic functions in the liver, which may possibly lead to chronic inflammation and malignancy risks. These findings highlight the role of Klrb1 in hepatic health.

Antibiotic concentrations induce morphological changes and increase biofilm formation in multi-antibiotic and heavy metal resistant Kluyvera cryocrescens and Serratia fonticola

Water pollution is the biggest challenge that has rendered existing water resources unusable due to contamination with antibiotics and heavy metals. Antibiotics are often used to treat bacterial diseases. Heavy metals, on the other hand, are micro-pollutants that pose a threat to aquatic systems, especially when they accumulate in nature. Increasing pollution and the uncontrolled use of antibiotics have exposed bacteria to non-lethal concentrations (sub-MIC), potentially leading to resistance. In this study, Kluyvera cryocrescens and Serratia fonticola were isolated from a freshwater source and characterised. The resistance profiles of the isolates to 16 antibiotics and 8 heavy metals were determined, revealing that they are multidrug-resistant. The effects of sub-MICs (MIC/2 and MIC/4) of antibiotics on biofilm formation, siderophore production, and cell morphology of bacteria were analysed. It was found that at some sub-MIC values of kanamycin, tetracycline, meropenem, erythromycin, and clarithromycin, biofilm formation by K. cryocrescens increased. An increase in biofilm production was also observed in S. fonticola at sub-MIC values of imipenem, meropenem, ceftazidime, ciprofloxacin, and clarithromycin. Moreover, significant morphological changes were observed in both isolates following treatment with meropenem, ciprofloxacin, and ceftazidime. After treatment with meropenem, the typical rod-shaped (bacillary) morphology of the isolates shifted to a round (coccoid) form. In contrast, the bacteria developed into long filaments after treatment with ciprofloxacin and ceftazidime. These changes in the bacteria may favour the development of resistance and pose challenges for the prevention and treatment of diseases. Therefore, it is crucial to understand how sub-MIC levels of antimicrobial agents alter the virulence properties of bacteria.