Causative Research Articles

Prevalence of <i>Wuchereria bancrofti</i> and <i>Plasmodium Spp.</i> infection in <i>Anopheles</i> mosquitoes and human blood sampled from Matayos in Busia County, Western Kenya

INTRODUCTION Lymphatic filariasis and malaria are mosquito-borne diseases and are co-endemic in coastal Kenya. We evaluated the occurrence of co-infections with Wuchereria bancrofti and Plasmodium falciparum, the causative agents of Lymphatic filariasis and malaria, respectively, in humans and known Anopheles vectors from Matayos constituency, Busia County, western Kenya. MATERIALS AND METHODS The samples were collected purposively based on clinical case reports. Members of the An. gambiae and An. funestus species complexes present and the presence of W. bancrofti and P. falciparum were detected using Polymerase Chain Reaction (PCR). Positive PCR amplicons were purified and Sanger sequenced. RESULTS In this study, 292 Anopheles mosquitoes were analyzed, and 288 of these (98.63%) were successfully identified by PCR. The majority of mosquitoes identified belonged to the An. funestus complex (85.76%) while An. gambiae complex mosquitoes comprised 14.24%. Two W. bancrofti infections were detected in the mosquitoes, one each in An. leesoni and An. funestus s.s. with an infection rate of 0.46% and 4.17% respectively. No P. falciparum was detected in the mosquito or human blood samples and only 2 blood samples (2.17%) were positive for W. bancrofti. Phylogenetic analysis based on the sequenced 18S rRNA gene showed that all W. bancrofti sequences from this study shared a close relationship with W. bancrofti sequences distributed in other regions. No case of co-infection of P. falciparum and W. bancrofti was found in the mosquito or blood samples analyzed. CONCLUSION This study confirms the presence of W. bancrofti infection in the human population and mosquito vectors in Matayos. The study also indicated that the majority of Anopheles mosquitoes from the study area belong to An. funestus complex. This study recommends additional screening before Mass Drug Administration, and that mosquito control programs be strengthened in the study area.

Potato NPH3/RPT2-like (NRL) member StNRL-9 interacts with Stphots and negatively regulates late blight resistance.

Blue light enhances the susceptibility of Nicotiana benthamiana to Phytophthora infestans, a causative agent of late blight disease. Investigating how blue light affects potato late blight resistance is an interesting aspect of exploring new ways to control late blight disease. Blue light photoreceptor phototropins (phot1, phot2) and their downstream interact protein StNRL1 have been shown to negatively regulate late blight resistance. In order to investigate whether other potato NPH3/RPT2-Like (NRL) family members are involved in regulating late blight resistance, this study focused on the potato NRL proteins containing RxSxS motif at the C-terminus. Another potato NRL protein StNRL-9, containing RxSxS motifs, was found to negatively regulate P. infestans resistance in potato and N. benthamiana. Overexpression of StNRL-9 in potato and N. benthamiana suppresses the accumulation of reactive oxygen species (ROS) and expression of the PTI marker genes NbWRKY7 and NbWRKY8. Similar to StNRL1, StNRL-9 interacts with the blue light receptors Stphot1 and Stphot2 on the cell membrane and could promote the degradation of a positive immune regulator StSWAP70. However StNRL-9 does not inhibit INF1-mediated cell death (ICD), whichis different from the StNRL1 that inhibits ICD, indicating that both StNRL1 and StNRL-9 inhibit plant immunity in diverse ways. This study provides valuable information for further exploration of how plant phototropins and NRL family proteins regulate plant immunity.

Reclassification of the first Bacillus tropicus phage calls for reclassification of other Bacillus temperate phages previously designated as plasmids

Bacillus tropicus is a recently identified subspecies of the Bacillus cereus group of bacteria that have been shown to possess genes associated with antimicrobial resistance (AMR) and identified as the causative agent for anthrax-like disease in Chinese soft-shelled turtles. In addition, B. tropicus has demonstrated great potential in the fields of bioremediation and bioconversion. This article describes the comparative genomics of a Bacillus phage vB_Btc-RBClinn15 (referred to as RBClin15) infecting the recently identified B. tropicus AOA-CPS1. RBClin15 is a temperate phage with a putative parABS partitioning system as well as an arbitrium system, which are presumed to enable extrachromosomal genome maintenance and regulate the lysis/lysogeny switch, respectively. The temperate phage RBClin15 has been sequenced however, was erroneously deposited as a plasmid in the NCBI GenBank database. A BLASTn search against the GenBank database using the whole genome sequence of RBClin15 revealed seven other putative temperate phages that were also deposited as plasmids in the database. Comparative genomic analyses shows that RBClin15 shares between 87 and 92% average nucleotide identity (ANI) with the seven temperate phages from the GenBank database. All together RBClin15 and the seven putative temperate phages share common genome arrangements and < 29% protein homologs with the closest phages, including 0105phi7-2. A phylogenomic tree and proteome-based phylogenetic tree analysis showed that RBClin15 and the seven temperate phages formed a separate branch from the closest phage, 0105phi7-2. In addition, the intergenomic similarity between RBClin15 and its closely related phages ranged between 0.3 and 47.7%. Collectively, based on the phylogenetic, and comparative genomic analyses, we propose three new species which will include RBClin15 and the seven temperate phages in the newly proposed genus Theosmithvirus under Caudoviricetes.

Virulence genes and antibiotic susceptibility patterns of Escherichia coli isolated from nosocomial urinary tract infections in the northwest of Iran during 2022-2023: A cross-sectional study.

Urinary tract infections (UTIs) are prevalent among hospitalized patients, constituting the most frequent health-care infections. Uropathogenic Escherichia coli (UPEC) is leading causative agent of UTIs. The present study was aimed to examine the susceptibility of UPEC isolates obtained from nosocomial cases to antibiotics, as well as their biofilm formation capability and frequency of virulence genes. A total of 100 UPEC isolates were collected from nosocomial UTIs at Imam Reza Hospitals in Tabriz, Iran, spanning from April 2022 to January 2023. The antimicrobial susceptibility patterns were evaluated using the disk diffusion method, along with the detection of broad-spectrum β-lactam enzymes (ESBLs) and carbapenemases. The ability of isolates to form biofilms was assessed using the microtiter-plate method, while the PCR method was employed to identify the presence of virulence genes. The highest resistance was observed toward piperacillin (82%), followed by aztreonam and ciprofloxacin (81%), while the lowest resistance was found against piperacillin/tazobactam (12%) and meropenem (9%). ESBLs were detected in 62% of the isolates. The microtiter-plate results revealed strong, moderate, and weak biofilm formation abilities in 32%, 33%, and 24% of the isolates, respectively. The most prevalent virulence gene was fimA (74%) followed by hlyF (68%), papA (44%), papC (32%), iroN (26%), and cnf (20%). The elevated levels of resistance to multiple antimicrobial agents, coupled with the co-presence of virulence genes and biofilm formation abilities, contribute to the persistence of UPEC-related infections, particularly in hospitalized patients. These findings underscore the necessity of implementing an effective program to control nosocomial UTIs caused by UPEC in the healthcare centers.

Pediatric limbal stem cell deficiency: An overview of a rarely studied pathology.

The cornea is the outermost transparent layer of the eye, and the continuous renewal of the corneal epithelium is important for its transparency. This process is primarily facilitated by corneal stem cells, most of which are found at the limbus. However, any deterioration or damage in this region leads to corneal conjunctivalization and consequent limbal stem cell deficiency (LSCD), which compromises corneal transparency. LSCD is an important condition, especially in the pediatric population, as it can lead to corneal vascularization, opacity and ultimately loss of vision and subsequent amblyopia, unlike adults. Although pediatric LSCD is often due to chemical injuries, as in adults, it is also caused by conditions such as congenital aniridia, Steven Johnson Syndrome and various other immunological disorders. Appropriate and timely treatment in pediatric LSCD is of particular importance in preventing progression to amblyopia, unlike adults. Accurate staging of the disease is essential for the necessary medical and surgical treatment decision. While medical approaches are at the forefront to eliminate the causative agent and improve the ocular surface in reversible cases, it is essential to replace the limbal stem cells lost in advanced disease. For these replacement procedures, it is noteworthy that there is a tendency for minimally invasive methods compared to adults to avoid possible complications due to long life expectancy in children. In conclusion, although there are various reviews on limbal stem cell deficiency (LSCD) in adults, we believe that this review for childhood LSCD will make an important contribution to the literature, since the relevant literature currently reported for the pediatric population is limited.

Detection of Hepatovirus A (HAV) in wastewater indicates widespread national distribution and association with socioeconomic indicators of vulnerability.

Wastewater-based epidemiology, which seeks to assess disease occurrence in communities through measurements of infectious disease biomarkers in wastewater, may represent a valuable tool for understanding the occurrence of hepatitis A infections in communities. In this study, we measured concentrations of Hepatovirus A (HAV) RNA, in samples from 191 wastewater treatment plants spanning 40 US states and the District of Columbia from September 2023 to June 2024 and compared the measurements with traditional measures of disease occurrence. Nationally, 13.76% of the 21,079 wastewater samples were positive for HAV RNA, and both concentrations and positivity rates were associated with NNDSS hepatitis A case data nationally (Kendall rank correlation coefficient = 0.20, concentrations; and 0.33, positivity rate; both P < 0.05). We further demonstrated that higher rates of wastewater HAV detection were positively associated with socioeconomic indicators of vulnerability including homelessness and drug overdose deaths (both P < 0.0001). Areas with above average levels of homelessness were 48% more likely to have HAV wastewater detections, while areas with above average levels of drug overdose deaths were 14% more likely to have HAV wastewater detections. Using more granular case data, we present a case study in the state of Maine that reinforces these results and suggests a potential lead time for wastewater over clinical case detection and exposure events. The ability to detect HAV RNA in wastewater before clinical cases emerge could allow public health officials to implement targeted interventions like vaccination campaigns.IMPORTANCEDespite the existence of a highly effective vaccine for hepatitis A, outbreaks in vulnerable populations remain common. The disease can be asymptomatic or subclinical, and disproportionately impacts populations with inadequate access to healthcare, leading to a severe underestimation of the occurrence of this viral infection. This study investigates the potential for wastewater measurements of biomarkers of the causative agent of hepatitis A (HAV RNA) to provide insights into disease occurrence. Results highlight the potential for wastewater-based epidemiology to be a complementary tool to traditional surveillance for monitoring and controlling HAV transmission.

Confirmation of Candidatus Liberibacter asiaticus in Asian Citrus Psyllids and Detection of Asian Citrus Psyllids in Commercial Citrus in Georgia (U.S.A.).

The Asian citrus psyllid (ACP) is the vector of Candidatus Liberibacter asiaticus (CLas), the causal agent of citrus greening or Huanglongbing (HLB), one of the most devastating citrus diseases worldwide. The citrus industry in Georgia (U.S.A.) is in the process of a rapid expansion, and based on experiences with HLB in Florida, there is great concern about the potential impacts of HLB on this emerging industry. Prior to 2023, ACP had been identified in residential citrus trees in isolated Georgia counties but little to no testing of psyllids for CLas had occurred. However, in 2023, one individual psyllid collected from Chatham County was confirmed positive for CLas by PCR and sequencing. Furthermore, during 2023, ACP adults and nymphs were identified for the first time in a Georgia commercial citrus grove. The finding of ACP in a commercial planting represents a significant risk for CLas dissemination, and thereby has the potential to stall the rapid expansion of Georgia's citrus industry. In the coming years, surveillance and testing of ACP from commercial groves will be essential for the early detection and management of HLB and its vector to reduce HLB spread within Georgia's commercial groves.

Genetic Diversity and Recombination Analysis of Canine Parvoviruses Prevalent in Central and Eastern China, from 2020 to 2023

Canine parvovirus type-2 (CPV-2), the primary causative agent of serious canine enteric diseases, is highly contagious and associated with high fatality rates worldwide. To comprehend the current emergence of CPV-2 in central and eastern China, 130 rectal swabs from domestic or stray dogs with gastroenteritis symptoms were collected during 2020–2023. A total of 118 positive samples were detected via polymerase chain reaction, and further used to amplify and sequence the VP2 gene. Sequence analysis of the deduced amino acids of VP2 protein indicated that CPV-2c was the most prevalent variant (n = 106, 89.83%), followed by the novel CPV-2a (n = 10, 8.47%) and CPV-2b (n = 2, 1.69%) variants. The VP2 protein from the obtained and reference strains showed 86.95% (AH2103 and HB2108) to 99.94% identity. Based on the nine predicted recombination events, some prevalent CPV-2c strains were highly similar to previously isolated strains, indicating their complex evolution and recombination. The predicted analysis suggested that mutations in the antigen epitope (Val219Ile, Phe267Tyr, and Asn426Glu) and other mutations (Met87Leu, Ile101Thr, and Ser297Ala) affect the tertiary structure of the VP2 protein. This research will help us understand the recent evolution and mutation of Chinese CPV-2 and provide suggestions for updating the CPV-2 vaccine.

Potential novel HIV-1 reverse transcriptase inhibitors: a modeling and evaluation approach

Human immunodeficiency viru (HIV) is the causative agent of acquired immunodeficiency syndrome (AIDS), a disease that severely weakens the immune system and makes patients more susceptible to infections. Although there is no definitive cure for HIV, advances in drug development offer promising prospects. In this study, we targeted HIV-1 reverse transcriptase by performing virtual screening (VS) to identify novel candidate compounds. From a database of compounds similar to the inhibitor thymidine-5'-triphosphate (TTP), three compounds (CID441663, CID123650073, and CID123789980) were selected for their docking scores, which outperformed those of the reference compound TTP (-6.2302 kcal/mol). These compounds were then subjected to ADMET, PASS, and DFT analyses. Interestingly, all three ligands showed a broad spectrum of predicted antiviral activity, including targets related to human herpes virus and HIV. Specifically, while TTP primarily targets HIV-1 reverse transcriptase, the top three ligands were predicted to target HIV-1 integrase, with CID441663 and CID123789980 displaying higher confidence in this target compared to CID123650073. These findings suggest that the candidate ligands should undergo further in vitro validation to determine their precise roles as inhibitors or antagonists, and to confirm their selective targeting of HIV-related proteins.

Biosensing technology for detection and assessment of pathogenic microorganisms.

At present, the prevalence of infectious diseases is rising annually, making it an important risk factor for human health that should not be neglected. Consequently, infection control and prevention have become even more important. The key to determining and designing the most effective anti-infectious medication depends upon the immediate and accurate identification of the causative agent. The standard techniques used for routine infection screening and surveillance tests are shifting toward biosensors. Furthermore, biosensors are projected to be employed for microbiological detection to satisfy the higher accuracy required for clinical diagnosis. This is because of their compact size, real-time monitoring and ability to analyze large sample numbers with less sophistication and manpower requirement, which have allowed them to develop quickly with extensive uses. Biosensors have multiple applications in food safety, environmental surveillance, drug sensing and national security because they offer several advantages such as quick response, outstanding sensitivity, remarkable selectivity, high degree of accuracy and precision, ease of use and affordable price. This review highlights the performance aspects of recently developed biosensors for the detection of infectious bacteria and viruses in biological and environmental samples and emphasizes the significance of nanotechnology in signal amplification for enhanced biosensor performance and dependability.

A host shift as the origin of tomato bacterial canker caused by Clavibacter michiganensis.

The Actinomycetota (formerly Actinobacteria) genus Clavibacter includes phytopathogens with devasting effects in several crops. Clavibacter michiganensis, the causal agent of tomato bacterial canker, is the most notorious species of the genus. Yet, its origin and natural reservoirs remain elusive, and its populations show pathogenicity profiles with unpredictable plant disease outcomes. Here, we generate and analyse a decade-long genomic dataset of Clavibacter from wild and commercial tomato cultivars, providing evolutionary insights that directed phenotypic characterization. Our phylogeny situates the last common ancestor of C. michiganensis next to Clavibacter isolates from grasses rather than to the sole strain we could isolate from wild tomatoes. Pathogenicity profiling of C. michiganensis isolates, together with C. phaseoli and C. californiensis as sister taxa and the wild tomato strain, was found to be congruent with the proposed phylogenetic relationships. We then identified gene enrichment after the evolutionary event, leading to the appearance of the C. michiganesis clade, including known pathogenicity factors but also hitherto unnoticed genes with the ability to encode adaptive traits for a pathogenic lifestyle. The holistic perspective provided by our evolutionary analyses hints towards a host shift event as the origin of C. michiganensis as a tomato pathogen and the existence of pathogenic genes that remain to be characterized.

Epidemiological profile and mortality of infective endocarditis over the past decade: a systematic review and meta-analysis of 133 studies comprising 132,355 cases

Abstract Background Understanding the epidemiology of infective endocarditis (IE) is crucial in the context of an aging population, increased comorbidities, and the heightened occurrence of healthcare-associated cases. Comprehensive data on causative agents, affected valves, and associated mortality are essential for current clinical practice. Methods This systematic review was conducted according to the PRISMA guidelines. A random effects model meta-analysis was conducted. Eligible studies reporting outcomes on IE were identified through a search of the PubMed/Medline database from 2010 to 2021. Results One hundred-thirty-three studies with 132,584 patients from six continents were included in the analysis. The most common causative agents of IE were Staphylococci species in 36% of cases, followed by Streptococci species in 26% of cases and Enterococci species in 10% of cases. Of the studies providing further speciation, the predominant species was Staphylococcus aureus with an incidence of 29%, followed by Viridans Streptococcus with an incidence of 12%. We found an in-hospital/30-day mortality of 17% (CI: 16%-19%) from 109 studies worldwide. In the subgroup analysis, the highest mortality rates were observed in Latin America 33% (CI: 28%-38%) and Africa 25% (CI: 21%-30%), while the lowest mortality rates were reported in Oceania 13% (CI: 8%-19%), followed by North America 14% (CI: 11%-18%), Asia 15% (CI: 12%-18%), and Europe 17% (CI: 16%-19%). The aortic valve was affected in 46% of cases, followed by the mitral valve in 43%. Tricuspid valve IE and multivalvular IE were identified in 7% and 14% of the cases, respectively. Conclusion Our study highlights the shift in epidemiological profile of IE over the last decade with S. aureus identified as the most common causative microorganism of IE in almost one third of cases. IE remains a highly morbid and fatal condition with high mortality rates even in tertiary and high-expertise centers worldwide. While left-sided IE is by far more common, right-sided IE and multivalvular IE are not rare entities and should be considered early in the differential of patients presenting with suspected IE to decrease the risk of future complications.Global burden of infective endocarditis.

Grove-Level Analysis of the Titer and Prevalence of ‘Candidatus Liberibacter asiaticus’ and Wolbachia in Diaphorina citri, Vector of Citrus Huanglongbing

Huanglongbing (HLB, or citrus greening disease) affects all citrus varieties worldwide. In the United States, Asia, and South America, the causal agent is ‘ Candidatus Liberibacter asiaticus’ ( CLas), a phloem-limited, uncultured alphaproteobacterium. The hemipteran insect vector Diaphorina citri (Asian citrus psyllid) acquires and transmits CLas in a circulative, propagative manner. In addition to CLas, D. citri hosts multiple symbiotic bacterial species including Wolbachia (wDi). In D. citri, wDi has been sequenced and studied, but specific roles in D. citri biology are unknown. Using well-established quantitative PCR methods, we measured CLas titer in D. citri collected from four groves in central Florida with distinct HLB management strategies and tested whether CLas and wDi titer were correlated in a subset of these insects. Grove site had the largest effect on CLas titer. Sex had no effect on CLas titer, whereas a higher wDi titer was correlated with noninfected insects. Our results suggest that more directed follow-up research is necessary and important to clarify whether field management tactics influence CLas titer in D. citri and to better understand gene-by-environment interactions among D. citri, wDi, and CLas. Now that millions of trees in Florida have been treated with injectable formulations of oxytetracycline, which is likely to decrease bacterial populations in D. citri, this study may represent the last biologically meaningful snapshot of grove-level vector-pathogen ecology in the state during the HLB epidemic.

Infantile Intraparenchymal Brain Abscess due to Streptococcus pyogenes

Introduction Group A ß-hemolytic streptococcus (GABHS) are the most common bacterial cause of tonsillitis, and can cause noninvasive diseases such as pharyngitis and impetigo, as well as more severe invasive diseases. The incidence of invasive disease is 1-3/100,000 per year, and the morbidity and mortality rate is high. GABHS is rarely lead to brain abscesses. Case Report Acute phase reactants were found to be high in a 40-day-old patient who presented with fever, irritability and focal seizures. Acute phase reactants were high. Transfontanel ultrasonography showed increased thickness, echo and blood supply in the meninges. Brain magnetic resonance imaging (MRI) and diffusion MRI revealed a thick-walled abscess in the right cerebral hemisphere and parietooccipital parenchyma with diffusion restriction on diffusion-weighted images. Cerebrospinal fluid (CSF) polymerase chain reaction (PCR) test revealed S. pyogenes,and S. pyogenes grown in CSF culture. Initially, meropenem, vancomycin, metronidazole antibiotherapy was applied. Treatment was revised to cefotaxime and vancomycin after culture antibiogram and was completed for 8 weeks. Seizures regressed. Control brain imaging showed improvement. Restriction in left lower extremity movements remained. Physical therapy and rehabilitation was recommended and he was discharged. Conclusion GABHS, which is the causative agent of acute tonsillitis, rarely causes invasive disease which has high mortality and morbidity.

The Influence of Health Education on Vaccination Coverage and Knowledge of the School Population Related to Vaccination and Infection Caused by the Human Papillomavirus

Background/Objectives: Human papillomavirus (HPV) is a causative agent of infections and cancers of the reproductive and digestive tract, and vaccination is the most effective prevention method. This research aimed to assess the impact of health education on vaccination coverage and knowledge of the school population related to HPV infection and vaccination. Methods: This non-randomized clinical trial included 170 participants out of the 221 students in the generation of 2022/2023, who were divided into a group of Subjects and Controls and who self-assessed their knowledge and tested knowledge at four and two time points, respectively. Results: The study examined whether there is a difference in the share of vaccinated students of the entire generation compared to the previous generation (62% vs. 47%). The self-assessment and assessment of one’s knowledge in the group of subjects was significantly lower before education than during other time points during the research. At “moment zero”, there was no significant difference in the knowledge assessment between the groups. However, after 8 weeks, the knowledge assessment was significantly higher in the Subject group. Conclusions: The results suggest a positive impact of health education, which may contribute to raising awareness about the importance of prevention and vaccination against HPV.

Infective endocarditis on percutaneous aortic valve prosthesis: incidence, characteristics and comparison with endocarditis on surgically implanted aortic bioprostheses

Abstract Background Transcatheter aortic valve replacement (TAVR) has become a first-line therapeutic measure in patients with severe aortic stenosis, especially in selected patients who present a very high surgical risk; nevertheless, this technique is becoming increasingly widespread even among patients with a lower surgical risk. Infective endocarditis (IE) is an infrequent but very serious complication in patients undergoing TAVR implantation. The aforementioned generalization of this technique means that more and more patients are at risk of developing this complication which, in addition, seems to have some particularities with respect to endocarditis in other patients. Purpose The aim of our study was to analyze the incidence, clinical characteristics and mortality of IE in patients with TAVR, comparing them with IE in patients with surgically implanted prostheses (SAVR). Methods Observational, single-center, prospective cohort study including all cases of IE diagnosed and prospectively followed up in our center from 2008 to 2022, according to Duke or ESC diagnostic criteria, depending on the era. We identified cases of IE in patients with TAVR in this period and compared their characteristics with endocarditis in patients with surgical aortic prostheses. Results In our center 10 cases of IE have been diagnosed in patients with TAVR. Since 2008 this procedure has been successfully performed in 778 patients, which gives an incidence of 1.29% compared to 1.68% of its surgical counterpart with a total of 24 cases of IE. The clinical characteristics of these patients are shown in the table. With the exception of mean age (p= 0.006), there were no significant differences between the two groups. In approximately half of the cases the diagnosis was made early after valve replacement (&amp;lt;1 year after replacement). With respect to the causative microorganisms, the most prevalent agent was enterococci, followed by coagulase-negative staphylococci and staphylococcus aureus; in 17% of patients with SAVR the causative agent was not identified. The clinical evolution was similar in both groups, with a high proportion of severe complications and 50% of cardiac complications in the TAVR group. Half of the patients had a surgical indication at diagnosis, but only 50% underwent surgery. There were also no differences in mortality, which, nevertheless, was high, around 30%. Conclusions Despite the differences in mean age, no significant differences were found between the two groups. IE is an infrequent but serious complication in patients with prosthetic valves, with a high rate of serious complications and mortality regardless of its management.Baseline characteristics of patients

Antibacterial effects of Kampo products against pneumonia causative bacteria.

Community-acquired pneumonia is caused primarily by bacterial infection. For years, antibiotic treatment has been the standard of care for patients with bacterial pneumonia, although the emergence of antimicrobial-resistant strains is recognized as a global health issue. The traditional herbal medicine Kampo has a long history of clinical use and is relatively safe in treating various diseases. However, the antimicrobial effects of Kampo products against pneumonia-causative bacteria remain largely uncharacterized. In this study, we investigated the bacteriological efficacy of 11 Kampo products against bacteria commonly associated with pneumonia. Sho-saiko-To (9), Sho-seiryu-To (19), Chikujo-untan-To (91) and Shin'i-seihai-To (104) inhibited the growth of S. pneumoniae serotype 3, a highly virulent strain that causes severe pneumonia. Also, the growth of S. pneumoniae serotype 1, another highly virulent strain, was suppressed by treatment with Sho-saiko-To (9), Chikujo-untan-To (91), and Shin'i-seihai-To (104). Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against these strains ranged from 6.25-50 mg/mL and 12.5-25 mg/mL, respectively. Furthermore, Sho-saiko-To (9), Chikujo-untan-To (91), and Shin'i-seihai-To (104) suppressed the growth of antibiotic-resistant S. pneumoniae isolates. Additionally, Sho-saiko-To (9) and Shin'i-seihai-To (104) showed growth inhibition activity against Staphylococcus aureus, another causative agent for pneumonia, with MIC ranging from 6.25-12.5 mg/mL. These results suggest that some Kampo products have antimicrobial effects against S. pneumoniae and S. aureus, and that Sho-saiko-To (9) and Shin'i-seihai-To (104) are promising medicines for treating pneumonia caused by S. pneumoniae and S. aureus infection.

RNA interference protocols for gene silencing in the spittlebug Philaenus spumarius, vector of Xylella fastidiosa

RNA interference (RNAi) is double stranded RNA (dsRNA)-based gene silencing mechanism. Exogenous dsRNAs application to crops has raised as a powerful tool to control agricultural pests. In particular, several sap-feeder are important plant pathogens vectors, such as Philaenus spumarius, known as main vector of Xylella fastidiosa (Xf), causal agent of olive quick decline syndrome (OQDS) in southern Italy. Here, dsATP synthase beta (dsATP), dsLaccase (dsLacc) and dsGreen Fluorescent Protein (dsGFP) as control, were provided to spittlebug adults by microinjection or to nymphs fed on dsRNA-treated plant shoots. Treated insects were collected at different time points to monitor silencing efficiency over time, describing significant reduction of transcript levels from 8 to 24 days post treatment. Downregulation of target genes ranged from 2- to 16-fold compared to the corresponding dsGFP controls, where highest silencing effects were generally noticed for ATP synthase beta. Sequencing of libraries obtained from total smallRNA (sRNA) showed the generation of dsRNA-derived sRNAs by RNAi pathway, with majority of reads mapping exclusively on the correspondent dsRNA. Also, we characterized components of a functional RNAi machinery in P. spumarius. Further research is needed to clarify such mechanism, screen effective target lethal genes to reduce vector population and improve delivery strategies.

Sugarcane Yellow Leaf Virus – A Silent Threat?

Abstract Sugarcane yellow leaf virus (SCYLV) is the causal agent of yellow leaf disease, a significant threat to global sugarcane production. SCYLV is disseminated via infected planting material and transmitted by aphids, primarily by Melanaphis sacchari (Zehntner). The disease’s impact varies depending on the sugarcane cultivar, with some varieties showing little to no foliar symptoms, yet experiencing severe yield losses. Reliable diagnostic methods, including serological and molecular techniques, are crucial for accurate detection, though these methods vary in sensitivity. Advances in molecular techniques have revealed ten major SCYLV genotypes grouped into three phylogroups, further complicating detection efforts. Improved understanding of SCYLV’s distribution within the plant and its seasonal variability are yet to be understood. Management strategies focus on breeding SCYLV-resistant varieties, but this is challenging due to the virus’s variable impact on yield and the often asymptomatic nature of epidemics. Efforts to develop SCYLV-free propagative material have been implemented, but the virus can still spread via aphid vectors from neighbouring fields. Ongoing research aims to identify resistant cultivars, optimize diagnostic techniques, and better understand the epidemiology of SCYLV to mitigate its impact on sugarcane yield and quality. Information © The Authors 2024

Microbial Community Analysis Offers Insight into the Complex Origins of Plant Disease in a Smallholder Farm Context

Classical approaches to plant disease diagnosis assume a single pathogen/single disease paradigm. Here, we revisit the presumed role of Fusarium oxysporum as the causal agent of wilting and yellowing of chickpea plants on smallholder farms in Ethiopia. Contrary to expectations, detection of Fusarium DNA using conserved PCR primers failed to associate the pathogen with symptomatic plants. Instead, culture-independent sequencing of microbial communities nominated unexpected pathogens and revealed patchiness in the assembly of common microbial consortia. Surprisingly, tests of differential enrichment identified Phytophthora as the most common disease-associated taxon. More generally, across all field sites, multilevel pattern analysis identified indicator taxa whose patterns of co-occurrence demarcate discrete microbial communities and are consistent with a range of specific interactions, including mutualism and antagonism. Taken together, these data indicate that soilborne chickpea disease in Ethiopia has heterogeneous origins and that despite decades of emphasis and disease resistance breeding, the role of Fusarium as the frequent agent of chickpea disease in Ethiopia remains enigmatic.