Antivirulence and antipathogenic activity of Mayan herbal remedies against Pseudomonas aeruginosa

ETHNOPHARMACOLOGICAL RELEVANCE

The Yucatan Peninsula has a privileged wealth of vascular plants with which various Mayan herbal formulations have been developed. However, studies on their antipathogenic and antivirulence properties are scarce.

AIM OF THE STUDY

Identify antivirulence properties in Mayan herbal remedies and determine their antipathogenic capacity in burn wounds infected with Pseudomonas aeruginosa.

MATERIALS AND METHODS

An ethnobotanical study was conducted in Mayan communities in central and southern Quintana Roo, Mexico. Furthermore, the antipathogenic capacity of three Mayan herbal remedies was analyzed using an animal model of thermal damage and P. aeruginosa infection. Antivirulence properties were determined by inhibiting phenotypes regulated by quorum sensing (pyocyanin, biofilm, and swarming) and by the secretion of the ExoU toxin. The chemical composition of the most active herbal remedy was analyzed using molecular network analysis.

RESULTS

It was found that topical administration of the remedy called "herbal soap" (HS) for eleven days maintained 100% survival of the animals, reduced establishment of the bacteria in the burn and prevented its systemic dispersion. Although no curative effect was recorded on tissue damaged by HS treatment, its herbal composition strongly reduced swarming and ExoU secretion. Through analysis of Molecular Networks, it was possible to carry out a global study of its chemical components, and identify the family of oxindole monoterpenoid alkaloids and carboline and tetrahydropyrididole alkaloids. In addition, flavonols, flavan-3-ols, and quinic acid derivatives were detected.

CONCLUSIONS

The antipathogenic and antivirulence capacity of ancient Mayan remedies makes them a potential resource for developing new antibacterial therapies to treat burns infected by P. aeruginosa.

A new FRET-based fluorescent probe: Colorimetric and ratiometric detection of hypochlorite and anti-counterfeiting applications

Hypochlorite (ClO-), as the main component of widely used disinfectants in daily life, comes into closer contact with the human body, which can lead to a number of diseases. The high-performance method is increasingly needed to detect ClO- in our daily life. In this report, we successfully synthesized a FRET ratiometric fluorescent probe (NDAC) containing benzoxadiazole moieties and coumarin moieties bound via ethylenediamine. As expected, NDAC has excellent selectivity and anti-interference ability toward ClO-, and the ratio of fluorescence intensity (I471 nm/I533 nm) has a very good linear relationship with the concentration of ClO-, with a wide linear range (2.5-1750 μM) and low detection limit (0.887 μM). Furthermore, we have successfully applied it for the quantitative detection of ClO- in water samples in daily life. At the same time, there is a very clear change in the fluorescence color after the reaction of the NDAC with ClO-. The blue/green value (B/G) of this color change also shows a very good linear relationship to ClO- (5.0-1000 μM). Therefore, the NDAC has also been successfully used for test strip detection and quantitative detection of ClO- in actual samples through smartphone-based fluorescence image analysis, and this method can provide faster, more convenient and more accessible detection. In addition, NDAC sensors also have potential applications in the field of information anti-counterfeiting.

Novel compounds with dual inhibition activity against SARS-CoV-2 critical enzymes RdRp and human TMPRSS2

COVID-19 caused major worldwide problems. The spread of variants and limited treatment encouraged the design of novel anti-SARS-CoV-2 compounds. A series of compounds RH1-23 were designed to dually target RNA-dependent RNA polymerase (RdRp) and transmembrane serine protease 2 (TMPRSS2). Compared to remdesivir, in vitro screening indicated the highest selectivity and potent activity of RH11-13 with half maximum inhibitory concentration (IC50) 3.9, 5.7, and 19.72 nM, respectively. RH11-12 showed superior inhibition activity against TMPRSS2 and RdRP with IC50 (1.7 and 4.2), and (6.1 and 4.42) nM, respectively. WaterMap analysis and molecular dynamics studies demonstrated the superior enzyme binding activity of RH11 and RH12. On Vero-E6 cells, RH11 and RH12 significantly inhibited the viral replication with 66 % and 63.2 %, and viral adsorption with 44 % and 65 %, alongside virucidal effect with 51.40 % and 90.5 %, respectively. Furthermore, the potent activity of RH12 was tested on TMPRSS2-expressing cells (Calu-3) compared to camostat. RH12 exhibited selectivity index (26.05) similar to camostat (28.01) and comparable to its SI on Vero-E6 cells (22.6). RH12 demonstrated also a significant inhibition of the viral adsorption on Calu-3 cells with 60 % inhibition at 30 nM. The designed compounds exhibited good physiochemical properties. These findings indicate a broad-spectrum antiviral efficacy of the designed compounds, particularly RH12, with a promise for further development.

Emerging pharmacological approaches for Huntington's disease

Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by cognitive, motor, and psychiatric symptoms. Despite significant advances in understanding the underlying molecular mechanisms of HD, there is currently no cure or disease-modifying treatment available. Emerging pharmacological approaches offer promising strategies to alleviate symptoms and slow down disease progression. This comprehensive review aims to provide a critical appraisal of the latest developments in pharmacological interventions for HD. The review begins by discussing the pathogenesis of HD, focusing on the role of mutant huntingtin protein, mitochondrial dysfunction, excitotoxicity, and neuro-inflammation. It then explores emerging therapeutic targets, including the modulation of protein homeostasis, mitochondrial function, neuro-inflammation, and neurotransmitter systems. Pharmacological agents targeting these pathways are discussed, including small molecules, gene-based therapies, and neuroprotective agents. In recent years, several clinical trials have been conducted to evaluate the safety and efficiency of novel compounds for HD. This review presents an update on the outcomes of these trials, highlighting promising results and challenges encountered. Additionally, it discusses the potential of repurposing existing drugs approved for other indications as a cost-effective approach for HD treatment. The review concludes by summarizing the current state of pharmacological approaches for HD and outlining future directions in drug development. The integration of multiple therapeutic strategies, personalized medicine approaches, and combination therapies are highlighted as potential avenues to maximize treatment effectiveness.

Production of pyrimidine nucleosides in microbial systems via metabolic engineering: Theoretical analysis research and prospects

Pyrimidine nucleosides, as intermediate materials of significant commercial value, find extensive applications in the pharmaceutical industry. However, the current production of pyrimidine nucleosides largely relies on chemical synthesis, creating environmental problems that do not align with sustainable development goals. Recent progress in systemic metabolic engineering and synthetic biology has enabled the synthesis of natural products like pyrimidine nucleosides through microbial fermentation, offering a more sustainable alternative. Nevertheless, the intricate and tightly regulated biosynthetic pathways involved in the microbial production of pyrimidine nucleosides pose a formidable challenge. This study focuses on metabolic engineering and synthetic biology strategies aimed at enhancing pyrimidine nucleoside production. These strategies include gene modification, transcriptional regulation, metabolic flux analysis, cofactor balance optimization, and transporter engineering. Finally, this research highlights the challenges involved in the further development of pyrimidine nucleoside-producing strains and offers potential solutions in order to provide theoretical guidance for future research endeavors in this field.

A conserved role for AKT in the replication of emerging flaviviruses in vertebrates and vectors

One third of all emerging infectious diseases are vector-borne, with no licensed antiviral therapies available against any vector-borne viruses. Zika virus and Usutu virus are two emerging flaviviruses transmitted primarily by mosquitoes. These viruses modulate different host pathways, including the PI3K/AKT/mTOR pathway. Here, we report the effect on ZIKV and USUV replication of two AKT inhibitors, Miransertib (ARQ-092, allosteric inhibitor) and Capivasertib (AZD5363, competitive inhibitor) in different mammalian and mosquito cell lines. Miransertib showed a stronger inhibitory effect against ZIKV and USUV than Capivasertib in mammalian cells, while Capivasertib showed a stronger effect in mosquito cells. These findings indicate that AKT plays a conserved role in flavivirus infection, in both the vertebrate host and invertebrate vector. Nevertheless, the specific function of AKT may vary depending on the host species. These findings indicate that AKT may be playing a conserved role in flavivirus infection in both, the vertebrate host and the invertebrate vector. However, the specific function of AKT may vary depending on the host species. A better understanding of virus-host interactions is therefore required to develop new treatments to prevent human disease and new approaches to control transmission by insect vectors.

Multiplex PCR for gastrointestinal parasites in stool: Benchmarking against direct microscopy and simplex PCR

PURPOSE

To develop and validate a multiplex conventional PCR assay to simultaneously detect Cryptosporidium spp., Entamoeba histolytica, and Giardia lamblia in diarrheal samples as a rapid, cost-effective, and sensitive diagnostic tool for prevalent co-infections for improved diagnostic accuracy and efficiency in resource-limited settings.

METHODS

Stool samples collected from patients with gastrointestinal symptoms after taking written consent, processed via wet mount, iodine mount, and PCR assays. Cohen's kappa statistical analysis was done to test agreement.

RESULT

Among 240 patients, 28.75% showed intestinal protozoa via Microscopy; Single-plex and multiplex PCR demonstrated 100% concordance, detecting 27.9%; confirmed by sequencing. Highest parasite positivity was observed in transplant and immunocompromised patients, with moderate to almost perfect agreement between microscopy and molecular methods.

CONCLUSION

Multiplex-conventional PCR offers superior sensitivity and specificity over microscopy and 100% concordance with single-plex PCR, enabling rapid, cost-effective diagnosis of multiple parasites from single stool sample. Its adoption could revolutionize parasitic infection management in routine diagnostics.

First report of abdominal sepsis caused by a recently described species: Chimaeribacter arupi

We present a case of a 34-year-old patient with abdominal sepsis caused by an infrequent species: Chimaeribacter arupi. Genomic analysis confirmed the identification which is difficult to achieve by other methods so far. To our knowledge, this represents the first case of infection by this species reported in Argentina.

Revisiting the dimensions of universal vaccine with special focus on COVID-19: Efficacy versus methods of designing

Even though the use of SARS-CoV-2 vaccines during the COVID-19 pandemic showed unprecedented success in a short time, it also exposed a flaw in the current vaccine design strategy to offer broad protection against emerging variants of concern. However, developing broad-spectrum vaccines is still a challenge for immunologists. The development of universal vaccines against emerging pathogens and their variants appears to be a practical solution to mitigate the economic and physical effects of the pandemic on society. Very few reports are available to explain the basic concept of universal vaccine design and development. This review provides an overview of the innate and adaptive immune responses generated against vaccination and essential insight into immune mechanisms helpful in designing universal vaccines targeting influenza viruses and coronaviruses. In addition, the characteristics, safety, and factors affecting the efficacy of universal vaccines have been discussed. Furthermore, several advancements in methods worthy of designing universal vaccines are described, including chimeric immunogens, heterologous prime-boost vaccines, reverse vaccinology, structure-based antigen design, pan-reactive antibody vaccines, conserved neutralizing epitope-based vaccines, mosaic nanoparticle-based vaccines, etc. In addition to the several advantages, significant potential constraints, such as defocusing the immune response and subdominance, are also discussed.

Discovery and evolution of berberine analogues as anti-Helicobacter pylori agents with multi-target mechanisms

Thirty protoberberine derivatives, of which twenty five were new, were synthesized and evaluated for their anti-Helicobacter pylori (HP) activities, taking 2,3,10-trimethoxy-9-p-methylbenzylaminoprotopalmatine chloride 1 as the lead. Among them, berberine (BBR) derivative 7c displayed the highest potency against six tested metronidazole (MTZ)-resistant strains and two tested MTZ-susceptible strains with the MIC values of 0.4-1.6 μg/mL with favorable druglike profiles including low toxicity and high stabilities in plasma and artificial gastric fluid. Mechanistic study revealed that 7c might target HP urease with IC50 value of 0.27 μg/mL against Jack bean urease. Furthermore, 7c might change the permeability of the bacterial membrane and direct interact with HP DNA, which also contribute to its bactericidal activity. Therefore, BBR derivatives constituted a new family of anti-HP candidates, with the advantage of good safety profile and multi-target mechanisms, and are worthy for further investigation.

Risk factors for resistant gram-positive bacteremia in febrile neutropenic patients with cancer

BACKGROUND

Gram-positive bacteria are frequently resistant to empirical beta-lactams in febrile neutropenic patients with cancer. As microbiology and antibiotic susceptibility changes, we reevaluated the risk factors for resistant Gram-positive bacteremia in febrile neutropenic patients with cancer.

METHODS

Episodes of bacteremic febrile neutropenia in Seoul National University Hospital from July 2019 to June 2022 were reviewed. Resistant Gram-positive bacteria were defined as a pathogen susceptible only to glycopeptide or linezolid in vitro (e.g., methicillin-resistant staphylococci, penicillin-resistant viridans streptococci, and ampicillin-resistant enterococci). Episodes were compared to identify independent risk factors for resistant Gram-positive bacteremia.

RESULTS

Of 225 episodes, 78 (34.7%) involved resistant Gram-positive bacteremia. Multivariate analysis revealed that breakthrough bacteremia while being administered antibiotics (adjusted odds ratio [aOR], 6.794; 95% confidence interval [95% CI], 3.130-14.749; P < 0.001) and catheter-related infection (aOR 4.039, 95% CI 1.366-11.946; P = 0.012) were associated with resistant Gram-positive bacteremia. Chronic liver disease (aOR 0.231, 95% CI 0.059-0.905; P = 0.035) and hypotension at bacteremia (aOR 0.454, 95% CI 0.218-0.945; P = 0.035) were inversely associated with resistant Gram-positive bacteremia.

CONCLUSIONS

Resistant Gram-positive bacteria should be considered in breakthrough bacteremia and catheter-related infection in febrile neutropenic patients with cancer.

White light-driven enhanced cerium-doped carbon dots activity to combat multidrug-resistant bacterial infection

Infections caused by multidrug-resistant (MDR) bacteria are increasing and becoming an urgent global health crisis. The discovery and development of novel antibacterial agents to combat MDR are highly desirable. Here, we report the fabrication of cerium-doped carbon dots (CeCDs) with a simple hydrothermal method, which exhibit intrinsic broad efficacy against MDR bacteria including clinical isolates while maintaining low cytotoxicity and hemolytic effects. Importantly, the antibacterial activity of CeCDs is dramatically improved owing to the generation of reactive oxygen species (ROS) upon white light irradiation. Comprehensive analyses revealed that the CeCDs can penetrate the bacterial wall, disrupt the cell membrane, and prevent the biofilm formation, possibly hindering the bacterial resistance development. And the interaction of CeCDs with lipopolysaccharide (LPS) may contribute to the higher activity against Gram-negative bacteria strains. The treatment of CeCDs in a murine skin infection model can significantly reduce the number of bacteria on infected sites and accelerate wound healing by irradiation with light. Overall, CeCDs show great promise as low-cost and efficient antibacterial agents for chronic wounds and may be served as a powerful weapon to fight against the growing threat of MDR bacterial infection.

Key considerations for pathogen surveillance in wastewater

Wastewater surveillance (WWS) has received significant attention as a rapid, sensitive, and cost-effective tool for monitoring various pathogens in a community. WWS is employed to assess the spatial and temporal trends of diseases and identify their early appearances and reappearances, as well as to detect novel and mutated variants. However, the shedding rates of pathogens vary significantly depending on factors such as disease severity, the physiology of affected individuals, and the characteristics of pathogen. Furthermore, pathogens may exhibit differential fate and decay kinetics in the sewerage system. Variable shedding rates and decay kinetics may affect the detection of pathogens in wastewater. This may influence the interpretation of results and the conclusions of WWS studies. When selecting a pathogen for WWS, it is essential to consider it's specific characteristics. If data are not readily available, factors such as fate, decay, and shedding rates should be assessed before conducting surveillance. Alternatively, these factors can be compared to those of similar pathogens for which such data are available.

Potential role of hippocampal neurogenesis in spinal cord injury induced post-trauma depression

It has been reported both in clinic and rodent models that beyond spinal cord injury directly induced symptoms, such as paralysis, neuropathic pain, bladder/bowel dysfunction, and loss of sexual function, there are a variety of secondary complications, including memory loss, cognitive decline, depression, and Alzheimer's disease. The large-scale longitudinal population-based studies indicate that post-trauma depression is highly prevalent in spinal cord injury patients. Yet, few basic studies have been conducted to address the potential molecular mechanisms. One of possible factors underlying the depression is the reduction of adult hippocampal neurogenesis which may come from less physical activity, social isolation, chronic pain, and elevated neuroinflammation after spinal cord injury. However, there is no clear consensus yet. In this review, we will first summarize the alteration of hippocampal neurogenesis post-spinal cord injury. Then, we will discuss possible mechanisms underlie this important spinal cord injury consequence. Finally, we will outline the potential therapeutic options aimed at enhancing hippocampal neurogenesis to ameliorate depression.

Exploring the antiviral inhibitory activity of Niloticin against the NS2B/NS3 protease of Dengue virus (DENV2)

Dengue virus (DENV2) is the cause of dengue disease and a worldwide health problem. DENV2 replicates in the host cell using polyproteins such as NS3 protease in conjugation with NS2B cofactor, making NS3 protease a promising antiviral drug-target. This study investigated the efficacy of 'Niloticin' against NS2B/NS3-protease. In silico and in vitro analyses were performed which included interaction of niloticin with NS2B/NS3-protease, protein stability and flexibility, mutation effect, betweenness centrality of residues and analysis of cytotoxicity, protein expression and WNV NS3-protease activity. Similar like acyclovir, niloticin forms strong H-bonds and hydrophobic interactions with residues LEU149, ASN152, LYS74, GLY148 and ALA164. The stability of the niloticin-NS2B/NS3-protease complex was found to be stable compared to the apo NS2B/NS3-protease in structural deviation, PCA, compactness and FEL analysis. The IC50 value of niloticin was 0.14 μM in BHK cells based on in vitro cytotoxicity analysis and showed significant activity at 2.5 μM in a concentration-dependent manner. Western blotting and qRT-PCR analyses showed that niloticin reduced DENV2 protein transcription in a dose-dependent manner. Besides, niloticin confirmed the inhibition of NS3-protease by the SensoLyte 440 WNV protease detection kit. These promising results suggest that niloticin could be an effective antiviral drug against DENV2 and other flaviviruses.

Characterizing the gastrointestinal microbiome diversity in endangered Malayan Siamang (Symphalangus syndactylus): Insights into group composition, age variability and sex-related patterns

BACKGROUND

The gut morphology of Symphalangus syndactylus exhibits an intermediate structure that aligns with its consumption of fruit and ability to supplement its diet with leaves. The Siamang relies on its gut microbiome for energy extraction, immune system development, and the synthesis of micronutrients. Gut microbiome composition may be structured based on several factors such as age, sex, and habitat. No study has yet been carried out on the gut microbiota of the Hylobatidae members in Malaysia especially S. syndactylus.

METHODS

This study aims to resolve the gut microbiome composition of S. syndactylus by using a fecal sample as DNA source, adapting high-throughput sequencing, and 16S rRNA as the targeted region.

RESULTS

A total of 1 272 903 operational taxonomic units (OTUs) reads were assigned to 22 phyla, 139 families, and 210 genera of microbes. The {Unknown Phylum} Bacteria-2 is the dominant phyla found across all samples. Meanwhile, {Unknown Phylum} Bacteria-2 and Firmicutes are genera that have the highest relative abundance found in the Siamang gut.

CONCLUSIONS

This study yields nonsignificance relationship between Siamang gut microbiome composition with these three factors: group, sex, and age.

Severe community‑acquired pneumonia caused by Legionella gormanii in combination with influenza A subtype (H1N1) virus in an immunocompetent patient detected by metagenomic next‑generation sequencing: A case report

Legionella pneumonia is an atypical form of pneumonia caused by Legionella gormanii that can also lead to multiple organ diseases, including acute respiratory distress syndrome and multiple organ dysfunction syndrome. Legionella gormanii requires a long incubation period for culture in clinical practice using BCYE medium. The specificity of serum for serological detection is low, resulting in a relatively high rate of missed Legionella diagnoses. Contracting the H1N1 virus can lead to the misdiagnosis of Legionella gormanii. Metagenomic next-generation sequencing (mNGS) is a novel tool that can rapidly and accurately identify potential Legionella gormanii strains. A severe case of community-acquired pneumonia in a 79-year-old patient was reported. The patient was diagnosed with Legionella gormanii and influenza A subtype (H1N1) virus using mNGS at The First Affiliated Hospital, Zhejiang University School of Medicine. After anti-Legionella and antiviral therapy, the number of reads identifying Legionella gormanii in bronchoalveolar lavage fluid using mNGS decreased from 665 to 112 as the patient's condition gradually improved. A search of PubMed revealed few reports of Legionella gormanii in association with the influenza A subtype (H1N1) virus. Patients with severe pneumonia caused by Legionella and influenza A subtype H1N1 virus infections should be screened early for infections using methods such as mNGS. This approach enables early and precise treatment, simplifying the administration of antibiotics and enhancing patient outcomes.

The potential of marine natural Products: Recent Advances in the discovery of Anti-Tuberculosis agents

Tuberculosis (TB) is an infectious airborne disease caused by Mycobacterium tuberculosis. Since the 1990 s, many countries have made significant progress in reducing the incidence of TB and associated mortality by improving health services and strengthening surveillance systems. Nevertheless, due to the emergence of multidrug-resistant TB (MDR-TB), alongside extensively drug-resistant TB (XDR-TB) and TB-HIV co-infection, TB remains one of the lead causes of death arising from infectious disease worldwide, especially in developing countries and disadvantaged populations. Marine natural products (MNPs) have received a large amount of attention in recent years as a source of pharmaceutical constituents and lead compounds, and are expected to offer significant resources and potential in the fields of drug development and biotechnology in the years to come. This review summarizes 169 marine natural products and their synthetic derivatives displaying anti-TB activity from 2013 to the present, including their structures, sources and functions. Partial synthetic information and structure-activity relationships (SARs) are also included.

Prevalence and types of methicillin-resistant Staphylococcus aureus (MRSA) in meat and meat products from retail outlets and in samples of animal origin collected in farms, slaughterhouses and meat processing facilities. A review

Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of nosocomial and community infections, in some cases severe and difficult to treat. In addition, there are strains of MRSA that are specifically associated with food-producing animals. For this reason, in recent years special attention has been paid to the role played by foodstuffs of animal origin in infections by this microorganism. With the aim of gaining knowledge on the prevalence and types of MRSA in meat and meat products, a review was undertaken of work published on this topic since 2001, a total of 259 publications, 185 relating to meat samples from retail outlets and 74 to samples of animal origin collected in farms, slaughterhouses and meat processing facilities. Strains of MRSA were detected in 84.3% reports (156 out of 185) from retail outlets and 86.5% reports (64 out of 74) from farms, slaughterhouses and meat processing facilities, although in most of the research this microorganism was detected in under 20% of samples from retail outlets, and under 10% in those from farms, slaughterhouses and meat processing facilities. The meat and meat products most often contaminated with MRSA were pork and chicken. In addition to the mecA gene, it is crucial to take into consideration the mecB and mecC genes, so as to avoid misidentification of strains as MSSA (methicillin-susceptible Staphylococcus aureus). The great variety of methods used for the determination of MRSA highlights the need to develop a standardized protocol for the study of this microorganism in foods.

The monkeypox virus-host interplays

Monkeypox virus (MPXV) is a DNA virus belonging to the Orthopoxvirus genus within the Poxviridae family which can cause a zoonotic infection. The unexpected non-endemic outbreak of mpox in 2022 is considered as a new global threat. It is imperative to take proactive measures, including enhancing our understanding of MPXV's biology and pathogenesis, and developing novel antiviral strategies. The host immune responses play critical roles in defensing against MPXV infection while the virus has also evolved multiple strategies for immune escape. This review summarizes the biological features, antiviral immunity, immune evasion mechanisms, pathogenicity, and prevention strategies for MPXV.

Burkholderia cenocepacia ST-250 in cystic fibrosis patients in Switzerland: Genomic investigation of transmission routes

This report describes the characterization of Burkholderia cenocepacia isolates belonging to sequence type (ST)-250, detected in eight patients with cystic fibrosis (CF) in Switzerland. We retrospectively analyzed 18 isolates of B. cenocepacia ST-250 isolated between 2003 and 2015 by whole-genome sequencing and evaluated clinical and epidemiological data. Single nucleotide polymorphism analysis of the B.°cenocepacia ST-250 lineage showed that the isolates from all patients cluster tightly, suggesting that this cluster has a recent common ancestor. Epidemiological investigations showed that six out of eight patients acquired B.°cenocepacia ST-250 in the years 2001-2006, where participation in CF summer camps was common. Two patients were siblings. Genomic relatedness of the B. cenocepacia ST-250 isolates supported transmission by close contact, however, a common source or nosocomial routes cannot be excluded. With respect to the fatal outcome in six patients, our study shows the importance of infection control measurements in CF patients with B.°cenocepacia.

Approaches based on miRNAs in Behçet's Disease: Unveiling pathogenic mechanisms, diagnostic strategies, and therapeutic applications

Behçet's Disease (BD) is an intricate medical puzzle, captivating researchers with its enigmatic pathogenesis. This complex ailment, distinguished by recurrent mouth and genital lesions, eye irritation, and skin injuries, presents a substantial obstacle to therapeutic research. This review explores the complex interaction of microRNAs (miRNAs) with BD, highlighting their crucial involvement in the disease's pathophysiology. miRNAs, recognized for regulatory influence in diverse biological processes, hold a pivotal position in the molecular mechanisms of autoimmune diseases, such as BD. The exploration begins with examining miRNA biogenic pathways and functions, establishing a foundational understanding of their regulatory mechanisms. Shifting to the molecular landscape governing BD, the review highlights miRNA-mediated impacts on critical signaling pathways like Notch, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and protein kinase B (AKT)/mammalian target of rapamycin (mTOR), offering insights into intricate pathophysiological mechanisms. Dissecting the immunological landscape reveals the profound influence of miRNAs on BD, shedding light on the intricate modulation of immune responses and offering novel perspectives on disease etiology and progression. Beyond molecular intricacies, the review explores the clinical relevance of miRNAs in BD, emphasizing their potential as diagnostic and prognostic indicators. The discussion extends to the promising realm of miRNA-based therapeutic interventions, highlighting their potential in alleviating symptoms and altering disease progression. This comprehensive review, serving as a valuable resource for researchers, clinicians, and stakeholders, aims to decipher the intricate molecular tapestry of BD and explore the therapeutic potential of miRNAs.

Gastrointestinal parasites of cats in the Middle East (2000-2023): A literature review

BACKGROUND/OBJECTIVE

Gastrointestinal parasites in stray cats are of significant clinical and zoonotic importance and pose a potential threat to public health. Hence, the current review has practical implications as it aims to present the diversity and the prevalence of cat parasites in Middle Eastern countries.

METHODS

The research process was rigorous and thorough, spanning from 2000 to 2023. Data collection and analysis were conducted utilizing multiple international and national databases, including Google Scholar, Scopus, PubMed, and Irandoc. This meticulous approach ensures the reliability and validity of the findings, providing a solid foundation for further research and preventive measures.

RESULTS

A total of 159 articles were collected and comprehensively reviewed. Among these, 85 articles were from Iran, 25 from Türkiye, 20 from Iraq, 11 from Egypt, five from Qatar, three from Cyprus, three from Kuwait, and one each from the UAE, Saudi Arabia, Syria, Lebanon, Jordan, Israel, and Palestine. Toxocara cati was the most prevalent nematode, exhibiting the highest prevalence in Iran, ranging from 8% to 90%, followed by Egypt, with a range of 8.23% to 58.7%. In comparison, the lowest prevalence was recorded in Qatar at 8%. Hydatigera taeniaeformis, a common cestode in the feline, showed the highest prevalence in Qatar, with a range of 73.6% to 75.8%, while the lowest was in Kuwait at 0.8%. In Iran, the prevalence ranged from 0.9% to 64.7%. Toxoplasma gondii, a cosmopolitan protozoan, showcased the highest prevalence in Lebanon at 78.1% and the lowest in the UAE at 0.8%. In Iran, the prevalence ranged between 1.2% and 90%. Additionally, noteworthy patterns regarding the distribution and potential risk factors associated with these parasites were observed. While gender variations were not significant, environmental conditions such as high humidity and absence of sunlight exposure, along with the age and behavior of cats, were among the risk factors associated with the prevalence of parasites.

CONCLUSION

The prevalence of parasites among stray cats in Iran and other Middle Eastern countries remains notably high. This emphasizes the urgent need for a series of control and preventive measures. Implementing effective anti-parasitic strategies and emphasizing the development of multiple diagnostic methods are essential.

Varicella‑zoster virus‑associated meningitis followed peripheral facial palsy: A case report

Although central nervous system infection following varicella zoster virus infection is relatively common, subsequent peripheral nervous system infection is comparatively rare. The present case documents a case of meningitis after varicella-zoster virus (VZV) infection, which was then followed by peripheral facial palsy. Specifically, a 54-year-old female patient was first admitted to Shengli Oilfield Central Hospital (Dongying, China) with headache and fever. Physical examination revealed herpes that formed along the intercostal nerve in the left forebreast, armpit and back. Subsequently, neurological examination found cervical resistance in more than three fingers (neck resistance of less than two transverse fingers is not evidence of meningeal irritation; the neck resistance of this patient was approximately three transverse fingers, so the patient was presumed to be positive for meningeal irritation, highly suggestive of meningitis) and Kernig sign was positive. There were no significant abnormalities according to brain MRI and lumbar puncture pressure was 330 mmH2O. In addition, the leukocyte count was 734x106/l, 50% monocyte count, 50% multinucleated cells, chloride levels of 109.1 mmol/l, protein levels of 235 mg/dl and glucose levels of 4.18 mmol/l in the cerebrospinal fluid. DNA and RNA metagenomic detection of pathogenic microorganisms in the cerebrospinal fluid revealed the presence of VZV. The patient was therefore treated with acyclovir, ceftriaxone, mannitol and methylprednisolone, but then developed right peripheral facial palsy at 10 days after treatment. This complication was not found in the literature, and the occurrence of facial neuritis was unexpected. The active period of VZV virus was 21 days, and the patient had herpes 5 days before admission. The active period of the virus was considered to have subsided and the patient was in the recovery period. Moreover, the results of lumbar puncture showed that the white blood cells, the proportion of neutrophils and the protein in cerebrospinal fluid were all decreasing, which also indicated that the patient had entered the recovery period. The patient was discharged 18 days after admission. In conclusion, observations from the present case suggested that the clinical manifestations of VZV infection can be complex and varied, requiring the clinician to have an accurate understanding of its disease progression and treatment.

Novel β-lactam-β-lactamase inhibitors as monotherapy versus combination for the treatment of drug-resistant Pseudomonas aeruginosa infections: A multicenter cohort study

BACKGROUND

Data comparing the clinical outcomes of novel β-lactam-β-lactamase inhibitors given in combination versus monotherapy for the treatment of multidrug-resistant (MDR) P. aeruginosa infections are lacking.

METHOD

This retrospective cohort study included patients who received novel β-lactam-β-lactamase inhibitors as monotherapy or in combination for the treatment of MDR P. aeruginosa infections. The study was conducted between 2017 and 2022 in 6 tertiary care hospitals in Saudi Arabia. Overall in-hospital mortality, 30-day mortality, clinical cure, and acute kidney injury (AKI) were compared between recipients of monotherapy versus combination using multivariate logistic regression analysis.

RESULT

118 patients and 82 patients were included in monotherapy and combination therapy arms, respectively. The cohort represented an ill population with 56% in the intensive care unit and 37% in septic shock. A total of 19% of patients presented with bacteremia. Compared to monotherapy, combination therapy did not significantly differ in clinical cure (57% vs. 68%; P = 0.313; OR, 0.63; 95% CI, 0.36-1.14) in-hospital mortality (45% vs. 37%; P = 0.267; OR, 1.38; 95% CI, 0.78-2.45), or 30-day mortality (27% vs. 24%; P = 0.619; OR, 1.18; 95% CI, 0.62-1.25). However, AKI (32% vs. 12%; P = 0.0006; OR, 3.45; 95% CI, 1.67-7.13) was significantly more common in patients who received combination therapy.

CONCLUSION

Novel β-lactam-β-lactamase inhibitors when used in combination with other antibiotics did not add clinical benefit compared to their use as monotherapy in the treatment of MDR P. aeruginosa infections. A Combination regimen was associated with an increased risk of nephrotoxicity.

A case report of acute Q fever with low-read detection of Coxiella burnetii genome by next-generation metagenomic sequencing

The case presents a 47-year-old man with sudden abdominal pain and fever, but the cause was uncertain. Through metagenomic next-generation sequencing (mNGS) and detecting Q fever antibodies in serum, along with the patient's clinical and epidemiological history, a precise diagnosis was made, enabling timely and proper treatment.

Carbapenem-resistant Klebsiella pneumoniae strains isolated from clinical specimens in Siirt, Türkiye; molecular characterization and antimicrobial resistance genes detection

This study aimed to molecularly identify carbapenem-resistant Klebsiella pneumoniae (CRKP) strains isolated from clinical samples and to determine antibiotic resistance genes. Only carbapenem-resistant strains were included in our study. Of the 35 CRKP strains, 18 (51.4%) were extensive drug, 11 (31.4%) were multi-drug, and 6 (17.1%) were pan-drug resistances. PCR amplification revealed that 25% of the strains carried the OXA-51, 20% the OXA-48, and %5 the OXA23 genes. Multilocus sequence typing (MLST) analysis based on seven house-keeping genes revealed sequence type 39. The capsule and O-antigen types were determined as KL103 and O2a, respectively. WGS analysis revealed the existence of β-lactamase, aminoglycoside, sulfonamide, Phenicol, and Fosfomycin-resistant genes. While the K. pneumoniae OmpK37 gene was detected in all 3 strains, the OmpK36 gene was detected only in the CRSU20 strain. This study is important as it is the first study to perform molecular analysis of CRKP strains from Siirt, Türkiye.

Preference and regulation mechanism mediated via mobile genetic elements for antibiotic and metal resistomes during composting amended with nano ZVI loaded on biochar

This study assessed the effectiveness of nano zero-valent iron loaded on biochar (BC-nZVI) during swine manure composting. BC-nZVI significantly reduced the abundance of antibiotic resistance genes (ARGs), metal resistance genes (MRGs), and mobile genetic elements (MGEs). BC-nZVI modified the preference of MGEs to carry ARGs and MRGs, and the corrosion products of BC-nZVI could destroy cell structure, hinder electron transfer between cells, and weaken the association between ARGs, MRGs, and host bacteria. Functional genes analysis revealed that BC-nZVI down-regulated the abundance of genes affecting the transmission and metabolism of ARGs and MRGs, including type IV secretion systems, transporter systems, two-component systems, and multidrug efflux pumps. Furthermore, the BC-nZVI decreased genes related to flagella and pili production and cell membrane permeability, thereby hindering the transfer of ARGs, MRGs, and MGEs in the environment. Redundancy analysis demonstrated that changes in the microbial community induced by BC-nZVI were pivotal factors impacting the abundance of ARGs, MRGs, and MGEs. Overall, this study confirmed the efficacy of BC-nZVI in reducing resistance genes during swine manure composting, offering a promising environmental strategy to mitigate the dissemination of these contaminants.

Development of progressive multifocal leukoencephalopathy after cord blood transplantation in a patient with refractory angioimmunoblastic T-cell lymphoma

A patient undergoing cord blood transplantation for refractory angioimmunoblastic T-cell lymphoma was subsequently managed with long-term immunosuppressants for chronic graft-versus-host disease (GVHD). On day 591 post-transplant, she exhibited disorientation and cognitive dysfunction. Magnetic resonance imaging (MRI) of the brain revealed two hyperintense foci in the white matter, suggestive of progressive multifocal leukoencephalopathy (PML). However, we did not include PML in the differential diagnosis at that time. Unfortunately, she developed progressive cognitive impairment, and repeated brain MRIs showed a progression in lesion size. She was still taking immunosuppressants to control her GVHD, therefore we suspected PML. The diagnosis of PML was confirmed through the detection of a John Cunningham (JC) virus in the cerebrospinal fluid on day 640 post-transplant. This report highlights the critical need to consider PML in differential diagnoses for post-allogeneic transplant patients, especially those who exhibit progressive neurological symptoms while on prolonged immunosuppressant therapy.

In vitro interactions of combinations of colistin with meropenem, rifampicin and tigecycline in colistin-resistant, biofilm-forming Klebsiella pneumoniae

In this study, it was aimed to reveal the in vitro interactions of combinations of colistin with meropenem, rifampicin and tigecycline in colistin-resistant, biofilm-forming Klebsiella pneumonia. A total of 30 isolates, 15 of which formed biofilms and 15 did not form biofilms, were randomly selected from K. pneumoniae isolates growing in blood samples. The synergy rates of colistin-meropenem, colistin-tigecycline, colistin-rifampicin combinations in planktonic/sessile bacteria are; It was determined as 83,3%/73,3%, 66,6%/33,3%, 100%/60% respectively. Biofilm inhibitory concentration (BIC) of colistin, meropenem, tigecycline, and rifampicin significantly increased after biofilm formation. The synergistic activity seen in the sessile form was independent of the planktonic form. Although a high synergistic effect was observed in the meropenem-colistin combination on sessile bacteria, colistin had very high BIC ​​in all combinations. Large-scale studies are needed in which the number of isolates studied is large, bacterial resistance profiles are evaluated genomically, and various antimicrobial groups are included.

Cellulose from bacteria as a delivery system for improved treatment of infectious diseases: A review of updates and prospects

Cellulose from bacteria is a high-purity biomaterial naturally produced by bacteria as part of their metabolic process. Although it inherently lacks antimicrobial activity, its modification with bioactive substances can significantly enhance its efficacy beyond that of the original compounds. This biomaterial features a unique ability to retain substantial quantities of liquids within its three-dimensional network, making it a prime candidate for biomedical applications. Versatile in its properties, it can be utilized across various industries. Previous research has highlighted its capacity to exhibit antimicrobial properties and to encapsulate nanostructured materials, thereby augmenting its antibacterial effectiveness. This review focuses on the use of cellulose from bacteria as a carrier for active compounds, specifically targeting antibacterial activity against drug-resistant strains. We explore its role in innovative bacterial cellulose-based systems, which present a promising solution for tackling bacterial resistance. This review aims to showcase the potential of bacterial cellulose in developing new devices and treatment strategies that address critical concerns in global health.

Antibiotic adjuvants against multidrug-resistant Gram-negative bacteria: important component of future antimicrobial therapy

The swift emergence and propagation of multidrug-resistant (MDR) bacterial pathogens constitute a tremendous global health crisis. Among these pathogens, the challenge of antibiotic resistance in Gram-negative bacteria is particularly pressing due to their distinctive structure, such as highly impermeable outer membrane, overexpressed efflux pumps, and mutations. Several strategies have been documented to combat MDR Gram-negative bacteria, including the structural modification of existing antibiotics, the development of antimicrobial adjuvants, and research on novel targets that MDR bacteria are sensitive to. Drugs functioning as adjuvants to mitigate resistance to existing antibiotics may play a pivotal role in future antibacterial therapy strategies. In this review, we provide a brief overview of potential antibacterial adjuvants against Gram-negative bacteria and their mechanisms of action, and discuss the application prospects and potential for bacterial resistance to these adjuvants, along with strategies to reduce this risk.

Serum Levels of Vitamins and Trace Elements in Patients with Visceral Leishmaniasis: a Systematic Review and Meta-analysis

Visceral leishmaniasis (VL), a fatal disease prevalent in more than 70 countries, poses significant health challenges, particularly in poor communities with limited access to healthcare. Vitamins and trace elements play a crucial role in immune function and may influence susceptibility to VL. This systematic review and meta-analysis aimed to assess the differences in serum vitamin and trace element levels in VL patients compared to healthy individuals. We conducted an extensive search of databases (PubMed, Embase, and Google Scholar) to identify potentially eligible articles published from inception to June 2023. Data extraction and quality assessment were carried out by two reviewers independently. RevMan software (version 5.4) was used for analysis. Standardized mean difference (SMD) with a confidence interval (CI) of 95% was used to summarize the findings. Ten studies comprising 546 VL patients and 535 controls were included in our study. The findings revealed significantly reduced serum retinol levels in VL patients in comparison to controls (SMD: - 0.67; 95% CI: [- 1.05, - 0.28]; p = 0.0008). Serum zinc levels were also substantially lower in VL patients, regardless of controls recruited from endemic (SMD: - 2.65; 95% CI: [- 3.86, - 1.44]; p < 0.0001) or non-endemic regions (SMD: - 1.99; 95% CI: [- 3.02, - 0.96]; p < 0.0002). However, VL patients exhibited significantly increased serum copper levels compared to controls (SMD: 2.51; 95% CI: [0.70, 4.32]; p = 0.007). Patients with VL had lower serum levels of zinc and retinol and higher levels of copper, indicating a possible role of these micronutrients in influencing VL susceptibility and progression.

Detection of foodborne pathogens in contaminated food using nanomaterial-based electrochemical biosensors

Foodborne pathogens are a grave concern for the for food, medical, environmental, and economic sectors. Their ease of transmission and resistance to treatments, such as antimicrobial agents, make them an important challenge. Food tainted with these pathogens is swiftly rejected, and if ingested, can result in severe illnesses and even fatalities. This review provides and overview of the current status of various pathogens and their metabolites transmitted through food. Despite a plethora of studies on treatments to eradicate and inhibit these pathogens, their indiscriminate use can compromise the sensory properties of food and lead to contamination. Therefore, the study of detection methods such as electrochemical biosensors has been proposed, which are devices with advantages such as simplicity, fast response, and sensitivity. However, these biosensors may also present some limitations. In this regard, it has been reported that nanomaterials with high conductivity, surface-to-volume ratio, and robustness have been observed to improve the detection of foodborne pathogens or their metabolites. Therefore, in this work, we analyze the detection of pathogens transmitted through food and their metabolites using electrochemical biosensors based on nanomaterials.

Inflammatory gene regulation by Cdc42 in airway epithelial cells

Cytokine release from airway epithelial cells is a key immunological process that coordinates an immune response in the lungs. We propose that the Rho GTPase, Cdc42, regulates both transcription and trafficking of cytokines, ultimately affecting the essential process of cytokine release and subsequent inflammation in the lungs. Here, we examined the pro-inflammatory transcriptional profile that occurs in bronchial epithelial cells (BEAS-2B) in response to TNF-α using RNA-Seq and differential gene expression analysis. To interrogate the role of Cdc42 in inflammatory gene expression, we used a pharmacological inhibitor of Cdc42, ML141, and determined changes in the transcriptomic profile induced by Cdc42 inhibition. Our results indicated that Cdc42 inhibition with ML141 resulted in a unique inflammatory phenotype concomitant with increased gene expression of ER stress genes, Golgi membrane and vesicle transport genes. To further interrogate the inflammatory pathways regulated by Cdc42, we made BEAS-2B knockdown strains for the signaling targets TRIB3, DUSP5, SESN2 and BMP4, which showed high differential expression in response to Cdc42 inhibition. Depletion of DUSP5 and TRIB3 reduced the pro-inflammatory response triggered by Cdc42 inhibition as shown by a reduction in cytokine transcript levels. Depletion of SESN2 and BMP4 did not affect cytokine transcript level, however, Golgi fragmentation was reduced. These results provide further evidence that in airway epithelial cells, Cdc42 is part of a signaling network that controls inflammatory gene expression and secretion by regulating Golgi integrity. Summary sentence:We define the Cdc42-regulated gene networks for inflammatory signaling in airway epithelial cells which includes regulation of ER stress response and vesicle trafficking pathways.

Serodiversity, antibiotic resistance, and virulence genes of Vibrio parahaemolyticus in oysters collected in coastal areas of northwestern Mexico between 2012 and 2020

This study aimed to determine the prevalence of V. parahaemolyticus in oysters from the northwestern coast of Mexico and to identify the serotypes, virulence factors, and antibiotic resistance of the strains. Oyster samples were collected from 2012 to 2020 from the northwest coast of Mexico; biochemical and molecular methods were used to identify V. parahaemolyticus from oysters; antiserum reaction to determine V. parahaemolyticus serotypes, and PCR assays were performed to identify pathogenic (tdh and/or trh) or pandemic (toxRS/new, and/or orf8) strains and antibiotic resistance testing. A total of 441 oyster samples were collected and tested for V. parahaemolyticus. Forty-seven percent of oyster samples were positive for V. parahaemolyticus. Ten different O serogroups and 72 serovars were identified, predominantly serotype O1:KUT with 22.2% and OUT:KUT with 17.3%. Twenty new serotypes that had not been previously reported in our region were identified. We detected 4.3% of pathogenic clones but no pandemic strains. About 73.5% of strains were resistant to at least one antibiotic, mainly ampicillin and ciprofloxacin; 25% were multi-drug resistant. In conclusion, the pathogenic strains in oysters and antibiotic resistance are of public health concern, as the potential for outbreaks throughout northwestern Mexico is well established.

Analysis of metagenome and metabolome disclosed the mechanisms of Dendrobium officinale polysaccharide on DSS-induced ulcerative colitis-affected mice

Currently, there is no known cause for ulcerative colitis (UC), an inflammatory bowel disease that is difficult to treat. This assay aimed to investigate the protective effects and mechanisms of Dendrobium officinale polysaccharide (DOP) in mice with acute UC induced by dextran sulphate sodium (DSS). We found that DOP could improve weight loss, decrease the disease activity index (DAI), and regulate the release of interleukin 2 (IL-2), IL-4, IL-6, and IL-10 in DSS-induced acute UC mice. Additionally, DOP preserved the integrity of the intestinal barrier in UC mice by increasing goblet cell density and maintaining tight junctions. DOP significantly enhanced total antioxidant capacity (T-AOC), and reduced glutathione (GSH), nitric oxide (NO), and malondialdehyde (MDA) levels in the bloodstream. In terms of serum biochemistry, DOP markedly elevated levels of bilirubin (BIL), alkaline phosphatase (ALP), total bile acid (TBA), creatinine (Crea), and creative kinase isoenzyme (CKMB). Furthermore, DOP increased the relative abundance of Lactobacillales. DOP also improved intestinal health and stimulated the synthesis of potent anti-inflammatory and antiviral substances by regulating the metabolism of purines, prostaglandins, and leukotrienes. Therefore, DOP can be considered a functional dietary supplement for the treatment of UC, as it improves the condition of DSS-induced UC mice.

Synthesis and broad-spectrum biocidal effect of novel gemini quaternary ammonium compounds

Since the discovery of antimicrobial agents, the misuse of antibiotics has led to the emergence of bacterial strains resistant to both antibiotics and common disinfectants like quaternary ammonium compounds (QACs). A new class, 'gemini' QACs, which contain two polar heads, has shown promise. Octenidine (OCT), a representative of this group, is effective against resistant microorganisms but has limitations such as low solubility and high cytotoxicity. In this study, we developed 16 novel OCT derivatives. These compounds were subjected to in silico screening to predict their membrane permeation. Testing against nosocomial bacterial strains (G+ and G-) and their biofilms revealed that most compounds were highly effective against G+ bacteria, while compounds 7, 8, and 10-12 were effective against G- bacteria. Notably, compounds 6-8 were significantly more effective than OCT and BAC standards across the bacterial panel. Compound 12 stood out due to its low cytotoxicity and broad-spectrum antimicrobial activity, comparable to OCT. It also demonstrated impressive antifungal activity. Compound 1 was highly selective to fungi and four times more effective than OCT without its cytotoxicity. Several compounds, including 4, 6, 8, 9, 10, and 12, showed strong virucidal activity against murine cytomegalovirus and herpes simplex virus 1. In conclusion, these gemini QACs, especially compound 12, offer a promising alternative to current disinfectants, addressing emerging resistances with their enhanced antimicrobial, antifungal, and virucidal properties.

Wake biofilm up to enhance suicidal uptake of gallium for chronic lung infection treatment

The hypometabolic and nutrient-limiting condition of dormant bacteria inside biofilms reduces their susceptibility to antibacterial agents, making the treatment of biofilm-dominating chronic infections difficult. Herein, we demonstrate an intratracheal aerosolized maltohexaose-modified catalase-gallium integrated nanosystem that can 'wake up' dormant Pseudomonas aeruginosa biofilm to increase the metabolism and nutritional iron demand by reconciling the oxygen gradient. The activated bacteria then enhance suicidal gallium uptake since gallium acts as a 'Trojan horse' to mimic iron. The internalized gallium ions disrupt biofilms by interfering with the physiological processes of iron ion acquisition and utilization, biofilm formation, and quorum sensing. Furthermore, aerosol microsprayer administration and bacteria-specific maltohexaose modification enable accumulation at biofilm-infected lung and targeted release of gallium into bacteria to improve the therapeutic effect. This work provides a potential strategy for treating infection by reversing the dormant biofilm's resistance condition.

Insights into the association of the Chlamydia trachomatis type III secretion chaperone complex, Scc4:Scc1, from sequential expression in Escherichia coli

Chlamydia trachomatis (CT) is the bacterial pathogen responsible for causing the most common sexually transmitted disease in the United States. This obligate, intracellular Gram-negative bacterium has a type III secretion system (T3SS) to invade host cells. CopN is an important effector, plug protein that mediates early interactions between the host and Chlamydia. CopN is chaperoned by a heterodimer, T3SS chaperone complex containing Scc4 and Scc1. Scc4 is a unique, bifunctional protein that, in addition to its T3SS chaperone activity, acts as an RNA polymerase (RNAP) binding protein. We hypothesized that the two functions occur at different points in CT's developmental cycle with Scc4 acting alone in the early-to-mid stages and the Scc4:Scc1 complex chaperoning CopN in the mid-to-late stages. To study the Scc4:Scc1 complex by NMR, we previously explored various methods of associating Scc4 and Scc1 in vitro to produce the complex with chain-selective isotopic labeling. Though co-expressed Scc4 and Scc1 form a stable complex, the in vitro association studies suggest that partial protein denaturation and/or components in E. coli lysate are necessary to form the stable complex. In this study Scc4 and Scc1 were sequentially expressed in E. coli under the control of different promoters, allowing separate isotopic labeling of each chain and complex formation in vivo. Sequential expression resulted in no or unstable complex formation depending on the culture medium used. These results, taken together with previous in vitro association studies, suggest that Scc4 and Scc1 assemble co-translationally to form the stable Scc4:Scc1 complex in E. coli.

A comprehensive review on biological funnel mechanism in lignin valorization: Pathways and enzyme dynamics

Lignin, a significant byproduct of the paper and pulp industry, is attracting interest due to its potential utilization in biomaterial-based sectors and biofuel production. Investigating biological methods for converting lignin into valuable products is crucial for effective utilization and has recently gained growing attention. Several microorganisms effectively decomposed low molecular weight lignins, transforming them into intermediate compounds via upper and lower metabolic pathways. This review focuses on assessing bacterial metabolic pathways involved in the breakdown of lignin into aromatic compounds and their subsequent utilization by different bacteria through various metabolic pathways. Understanding these pathways is essential for developing efficient synthetic metabolic systems to valorize lignin and obtain valuable industrial aromatic chemicals. The concept of "biological funneling," which involves examining key enzymes, their interactions, and the complex metabolic pathways associated with lignin conversion, is crucial in lignin valorization. By manipulating lignin metabolic pathways and utilizing biological routes, many aromatic compounds can be synthesized within cellular factories. Although there is insufficient evidence regarding the complete metabolism of polyaromatic hydrocarbons by particular microorganisms, understanding lignin-degrading enzymes, regulatory mechanisms, and interactions among various enzyme systems is essential for optimizing lignin valorization. This review highlights recent advancements in lignin valorization, bio-funneling, multi-omics, and analytical characterization approaches for aromatic utilization. It provides up-to-date information and insights into the latest research findings and technological innovations. The review offers valuable insights into the future potential of biological routes for lignin valorization.

Endophytic microbial diversity associated with commercial cultivar and crop wild relative banana variety could provide clues for microbial community management

Endophytes, microorganisms inhabiting internal plant tissues, play a pivotal role in plant growth and disease resistance. Moreover, previous studies have established that Musa plants derive disease protective functions from their microbiome. Notably, one of the crop wild relatives of banana, the Calcutta 4 variety, exhibits resistance to various phytopathogens such as Pseudocercospora fijiensis (P. fijiensis), while the Williams commercial cultivar (cv.) is highly susceptible. Therefore, this study aims primarily to characterize and compare the endophytic microbiota composition of Calcutta 4 and Williams banana plants when grown sympatrically. Alongside, differences in endophytic microbiome between plant sections (shoot or roots), growth phases (in vitro or greenhouse) and fitness factors such as the addition of plant growth-promoting bacteria Bacillus subtilis EA-CB0575 (T2 treatment) or infection by P. fijiensis (T3 treatment) were examined. Both culture-dependent and -independent techniques were used to evaluate these differences and assess the culturability of banana endophytes under varying conditions. Microbial cultures resulted in 331 isolates distributed across 54 genera when all treatments were evaluated, whereas 16 S sequencing produced 9510 ASVs assigned in 1456 genera. Alpha and beta diversity exhibited significant differences based on plant section, with an increase in phylogenetic diversity observed in plants with pathogen infection (T3) compared to control plants (T1). Additionally, four differentially abundant genera associated with nitrogen metabolism were identified in T3 plants and seven genera showed differential abundance when comparing varieties. When culture-dependent and -independent methods were compared, it was found that isolates represented 3.7 % of the genera detected by culture-independent methods, accounting for 12-41 % of the total data depending on the treatment. These results are crucial for proposing management strategies derived from crop wild relatives to enhance the resilience of susceptible commercial varieties against fitness factors affecting crop development. Additionally, they help to decipher the pathogenic effects of P. fijiensis in banana plants and advance the understanding of how plant domestication influences the endosphere.

Self-activated hydrogel cascade reactor integrated with glucose oxidase and silver nanoparticle for enhanced treatment of bacterial infection

The recognition of silver nanoparticles (AgNPs) as a nanozyme with peroxidase-like activity has offered a promising solution to address the challenges of bacterial resistance and argyria risk. However, the catalytic efficacy of AgNPs is limited by the need for a strong acidic environment and high concentrations of hydrogen peroxide (H2O2). In this work, we developed a self-activated hydrogel cascade reactor (AUGP) for enhanced treatment of bacterial infection. The AUGP integrates the properties of glucose oxidase (GOx) and polyacrylamide (pAAm) hydrogel microsphere. The confinement effect of pAAm hydrogel microsphere enables glucose oxidation to occur in a confined space, which creates an acidic environment to activate AgNPs activity, initiating the cascade reaction between GOx and AgNPs. Meanwhile, the confinement effect facilitates the accumulation of a high local concentration of H2O2, allowing AUGP to generate hydroxyl radicals (•OH) without the need for external H2O2. Additionally, the release of Ag+ from AUGP is achieved upon the generation of •OH. The synergistic action of Ag+ and •OH confers exceptional antibacterial efficacy to AUGP. Importantly, the etching effect of H2O2 ensures the absence of any residual AgNPs, reducing the risk of argyria. In vivo studies validated the efficacy of AUGP in wound disinfection with minimal toxicity.

Safety and tolerability of bronchoscopic and nebulised administration of bacteriophage

INTRODUCTION

Pseudomonas aeruginosa is an organism well known for causing significant morbidity and mortality in people living with chronic lung conditions such as cystic fibrosis. We describe the safety, tolerability, and potential efficacy of bronchoscopic and nebulised bacteriophage administration, offering insights into a potential breakthrough for the treatment of chronic infections particularly in children and adolescents.

METHOD

A 12-year-old female (F12) and a 17-year-old male (M17), both diagnosed with cystic fibrosis and chronic P. aeruginosa lung infection, underwent bacteriophage treatment (BT). The administration involved bronchoscopic instillation and subsequent nebulisation. This was performed concurrently with intravenous antibiotics and regular physiotherapy delivered in an in-patient setting for 14 days. Microbiological, clinical, and lung function assessments were conducted to assess this treatment modality.

RESULTS

No adverse events (fever, localised reaction, wheeze or bronchospasm) occurred during BT. F12 demonstrated a 4% increase, while M17 showed a 5% improvement in FEV1% from their best FEV1% over the past three years following BT. A 12% (F12) and an 8% (M17) improvement from baseline FEV1% was observed. For F12 P. aeruginosa was not isolated from her sputum despite 12 previous hospitalisations for intravenous antibiotics.

CONCLUSION

Bronchoscopic and nebulised routes of bacteriophage administration were well-tolerated in these two adolescents. This early report underscores the potential of this treatment modality and encourages clinicians and researchers to actively explore this innovative approach.

Portable SERS biosensor based on aptamer-assisted catalytic hairpin assembly signal amplification for ultrasensitive detection of Staphylococcus aureus

Bacteria infections pose a serious threat to public health, and it is urgent to develop facile and accurate detection methods. To meet the important need, a potable and high-sensitive surface enhanced Raman scattering (SERS) biosensor based on aptamer recognition and catalytic hairpin assembly (CHA) signal amplification was proposed for point-of-care detection of Staphylococcus aureus (S. aureus). The SERS biosensor contains three parts: recognition probes, SERS sensing chip, and SERS tags. The feasibility of the strategy was verified by gel electrophoresis, and the one-step test route was optimized. The bacteria SERS biosensor has a good linear relationship ranging from 10 to 107 CFU mL-1 with high sensitivity low to 5 CFU mL-1, and shows excellent specificity, uniformity, and repeatability on S. aureus identification and enumeration, which can distinguish S. aureus from other bacteria. The SERS biosensor shows a good recovery rate (95.73 %-109.65 %) for testing S. aureus spiked in milk, and has good practicability for detecting S. aureus infected mouse wound, which provides a facile and reliable approach for detection of trace bacteria in the real samples.

A super sandstorm altered the abundance and composition of airborne bacteria in Beijing

Sandstorm, which injects generous newly emerging microbes into the atmosphere covering cities, adversely affects the air quality in built environments. However, few studies have examined the change of airborne bacteria during severe sandstorm events. In this work, we analyzed the airborne bacteria during one of the strongest sandstorms in East Asia on March 15th, 2021, which affected large areas of China and Mongolia. The characteristics of the sandstorm were compared with those of the subsequent clean and haze days. The composition of the bacterial community of air samples was investigated using quantitative polymerase chain reaction (qPCR) and high-throughput sequencing technology. During the sandstorm, the particulate matter (PM) concentration and bacterial richness were extremely high (PM2.5: 207 µg/m3; PM10: 1630 µg/m3; 5700 amplicon sequence variants/m3). In addition, the sandstorm brought 10 pathogenic bacterial genera to the atmosphere, posing a grave hazard to human health. As the sandstorm subsided, small bioaerosols (0.65-1.1 µm) with a similar bacterial community remained suspended in the atmosphere, bringing possible long-lasting health risks.

The financial cost of coccidiosis in Algerian chicken production: a major challenge for the poultry sector

Coccidiosis, caused by parasites of the genus Eimeria, is a significant economic burden to the poultry industry. In this study, we conducted a comprehensive analysis to evaluate the financial losses associated with Eimeria infection in chickens in Algeria, relying on data provided by key stakeholders in the Algerian poultry industry to assess sub-clinical as well as clinical impact. We employed the updated 2020 version of a model established to estimate the cost of coccidiosis in chickens, taking into consideration specific cultural and technical aspects of poultry farming in Algeria. The findings predict economic losses due to coccidiosis in chickens of approximately £86.7 million in Algeria for the year 2022, representing £0.30 per chicken raised. The majority of the cost was attributed to morbidity (74.9%), emphasizing the substantial economic impact of reduced productivity including decreased bodyweight gain and increased feed conversion ratio. Costs associated with control measures made up 20.5% of the total calculated cost, with 4.6% of the cost related to mortality. These figures provide a clear indication of the scope and economic impact of Eimeria infection of chickens in Algeria, illustrating the impact of practices common across North Africa. They underscore the ongoing requirement for effective preventive and control measures to reduce these financial losses while improving productivity and welfare, ensuring the economic sustainability of the Algerian poultry industry.

Sigma metrics analysis of serology screening assays to enhance quality and efficiency in New Zealand blood services

Sigma metric analysis was conducted across two New Zealand Blood Services (NZBS) laboratories (Auckland and Christchurch) to optimize quality control (QC) procedures. We evaluated five assays (anti-HCV, HIV Ag/Ab combo, HTLV-I/II, HBsAg, and Syphilis) using internal quality control (IQC) and third-party daily QC data extracted from four Architect i2000SR instruments during Jan 2 -31st, 2023. Mean, standard deviation (SD), and coefficient of variation (CV%) were calculated, assuming zero bias. Sigma metrics were determined using the Total Allowable Error (TEa %) based on difference between positive control mean and signal-to-cutoff (s/co) cut-off. Most assays exhibited CV% values ≤10 % except for HBsAg IQC (18.5 %) and anti-HCV third-party QC (13.4 %) at Christchurch. TEa % ranged from 38 % to 90 %. Overall, the assays demonstrated Six Sigma performance (σ > 6), except for HBsAg IQC (3.97) and anti-HCV third-party QC (5.46) at Christchurch. These high-quality serology assays can benefit from simplified QC design without compromising blood safety.

Autochthonous Cryptococcus gattii genotype VGIIb infection in a Japanese patient with anti-granulocyte-macrophage colony-stimulating factor antibodies

A 31-year-old Japanese man presented with cerebral and pulmonary cryptococcosis. Cryptococcus gattii (C. gattii) genotype VGIIb was detected in the patient's sputum and cerebrospinal fluid specimens. The serum levels of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) antibodies were elevated in this patient, which has been associated with pulmonary alveolar proteinosis and is considered a risk factor for C. gattii infection. After undergoing >12 months of antifungal treatments, the patient showed improvements in symptoms and findings on brain and lung imaging. Several Japanese patients who develop C. gattii infection have also been reported; however, most of these patients have been infected outside Japan, as C. gattii infection is rare in Japan. Only one patient with C. gattii genotype VGIIb infection has been reported in Japan, and it is believed that this patient contracted the infection in China. In the present case, our patient has never been outside Japan, indicating that the infection originated in Japan. Our findings suggest that C. gattii might be spreading in Japan. Therefore, patients with positive serum anti-GM-CSF antibodies should be thoroughly monitored for C. gattii infection, even those living in Japan.