Chan Hao Sien, Hezerul Abdul Karim, Nouar AlDahoul
Soil-transmitted helminth (STH) infections continuously affect a large proportion of the global population, particularly in tropical and sub-tropical regions, where access to specialized diagnostic expertise is limited. Although manual microscopic diagnosis of parasitic eggs remains the diagnostic gold standard, the approach can be labour-intensive, time-consuming, and prone to human error. This paper aims to utilize a vision language model (VLM) such as Microsoft Florence that was fine-tuned to localize all parasitic eggs within microscopic images. The preliminary results show that our localization VLM performs comparatively better than the other object detection methods, such as EfficientDet, with an mIOU of 0.94. This finding demonstrates the potential of the proposed VLM to serve as a core component of an automated framework, offering a scalable engineering solution for intelligent parasitological diagnosis.
Konan Yao Jean Rodrigue, Ta Bi Tra Dieudonné, Berté Djakaridja
et al.
Vector control (VC) is one of the strategies employed to manage African trypanosomoses. This study aimed at assessing the effectiveness of a VC campaign against Glossina palpalis palpalis using tiny targets (TTs) impregnated with insecticide in an isolated, protected forest in Abidjan, Côte d’Ivoire, while considering ecological, genetic, and operational factors. Between January 2020 and September 2022, 2,712 TTs were deployed at 684 sites, covering a total area of 1.7 km2. VC monitoring was conducted using Vavoua traps during 12 evaluation surveys, between June 2020 and March 2023. Five months after the initial TT deployment, tsetse fly density had decreased by 98.53%. Although tsetse density remained low due to TT redeployment and reinforcement, there was a significant increase a few months after the last redeployment. VC appeared to have minimal impact on the genetic structuring of G. p. palpalis. This suggested recruitment of local surviving tsetse flies all along the VC campaign due to a low probability of tsetse coming into contact with TTs, or to the evolution of behavioral or physiological resistance to control efforts. The genetic study revealed that one of the microsatellite markers used, the GPCAG locus, exhibited a selection signature possibly in response to VC. This could partly explain the challenges encountered in eliminating a seemingly isolated tsetse population thriving in a particularly favorable habitat.
Abstract The N-terminal cleavage of the norovirus major capsid protein VP1 during in vitro expression is a widely observed phenomenon, yet the underlying mechanisms remain poorly understood. This study aimed to determine how N-terminal insertion sequences affect the cleavage and assembly of virus-like particles (VLPs). To this end, a series of recombinant GII.6 VP1 proteins with varied N-terminal insertion peptides were constructed and expressed using a baculovirus expression system. The expression, integrity, and assembly status of these proteins were analyzed using Western blot (WB), SDS-PAGE, transmission electron microscopy (TEM), and peptide fingerprinting analysis. Furthermore, a recombinant protein with a N-terminal FLAG tag was also constructed and expressed to investigate the characteristics of N-terminal cleavage. Our findings indicate that varied N-terminal insertion peptides produced different cleavage patterns with some peptide sequences showing inhibition of N-terminal cleavage. N-terminal FLAG-tagged fragment was not detected in cell lysate, further suggesting the complexity of the N-terminal cleavage. These results provide new insights into the molecular mechanisms of VP1 processing and its implications for virus-like particle (VLP) assembly.
Babesiosis is a tick-borne parasitic disease caused by the intraerythrocytic protozoan Babesia spp. and transmitted primarily by Ixodes ticks. The geographical distribution of the parasites coincides with the regions where their tick vectors are prevalent. More than 50 cases of human babesiosis have been reported in Europe, mainly associated with Babesia divergens, which causes acute disease in cattle and is transmitted by Ixodes ricinus. In contrast, the incidence of the disease in the USA is approximately 2000 cases per year, with the main causative agent being Babesia microti and the tick vector being Ixodes scapularis. Although babesiosis is primarily an animal disease, humans can also become acutely ill, particularly splenectomized and immunocompromised individuals. Clinical manifestations range from asymptomatic to severe disease with symptoms including fever, chills, hemoglobinuria and anemia. There is a risk of potentially fatal complications such as acute respiratory, renal or multi-organ failure, particularly in vulnerable populations. Diagnosis is primarily based on light microscopy and PCR testing, while serological methods are more appropriate for epidemiological studies. Treatment regimens typically include a 7-10 day course of either atovaquone plus azithromycin or clindamycin plus quinine. Human cases are associated with outdoor activities or living in rural areas during the warm months when tick activity is at its peak. Because of the increasing incidence in endemic regions and the potentially serious clinical consequences, babesiosis should be considered in the differential diagnosis of febrile illnesses of unknown origin.
We introduce a generalized version of the frog model to describe the invasion of a parasite population in a spatially structured immobile host population with host immunity on the integer line. Parasites move according to simple symmetric random walks and try to infect any host they meet. Hosts, however, own an immunity against the parasites that protects them from infection for a random number of attacks. Once a host gets infected, it and the infecting parasite die, and a random number of offspring parasites is generated. We show that the positivity of the survival probability of parasites only depends on the mean offspring and mean height of immunity. Furthermore, we prove through the construction of a renewal structure that given survival of the parasite population parasites invade the host population at linear speed under relatively mild assumptions on the host immunity distribution.
Akram A. Da’dara, Catherine S. Nation, Patrick J. Skelly
Abstract Background Schistosomiasis is a parasitic disease caused by trematodes of the genus Schistosoma. The intravascular worms acquire the nutrients necessary for their survival from host blood. Since all animals are auxotrophic for riboflavin (vitamin B2), schistosomes too must import it to survive. Riboflavin is an essential component of the coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD); these support key functions of dozens of flavoenzymes. Methods Here, using a combination of metabolomics, enzyme kinetics and in silico molecular analysis, we focus on the biochemistry of riboflavin and its metabolites in Schistosoma mansoni (Sm). Results We show that when schistosomes are incubated in murine plasma, levels of FAD decrease over time while levels of FMN increase. We show that live schistosomes cleave exogenous FAD to generate FMN and this ability is significantly blocked when expression of the surface nucleotide pyrophosphatase/phosphodiesterase ectoenzyme SmNPP5 is suppressed using RNAi. Recombinant SmNPP5 cleaves FAD with a Km of 178 ± 5.9 µM and Kcat/Km of 324,734 ± 36,347 M− 1.S− 1. The FAD-dependent enzyme IL-4I1 drives the oxidative deamination of phenylalanine to produce phenylpyruvate and H2O2. Since schistosomes are damaged by H2O2, we determined if SmNPP5 could impede H2O2 production by blocking IL-4I1 action in vitro. We found that this was not the case; covalently bound FAD on IL-4I1 appears inaccessible to SmNPP5. We also report that live schistosomes can cleave exogenous FMN to generate riboflavin and this ability is significantly impeded when expression of a second surface ectoenzyme (alkaline phosphatase, SmAP) is suppressed. Recombinant SmAP cleaves FMN with a Km of 3.82 ± 0.58 mM and Kcat/Km of 1393 ± 347 M− 1.S− 1. Conclusions The sequential hydrolysis of FAD by tegumental ecto-enzymes SmNPP5 and SmAP can generate free vitamin B2 around the worms from where it can be conveniently imported by the recently described schistosome riboflavin transporter SmaRT. Finally, we identified in silico schistosome homologs of enzymes that are involved in intracellular vitamin B2 metabolism. These are riboflavin kinase (SmRFK) as well as FAD synthase (SmFADS); cDNAs encoding these two enzymes were cloned and sequenced. SmRFK is predicted to convert riboflavin to FMN while SmFADS could further act on FMN to regenerate FAD in order to facilitate robust vitamin B2-dependent metabolism in schistosomes.
Parkinson's disease (PD) is a progressive neurodegenerative disease, and it is caused by the loss of dopaminergic neurons in the basal ganglia (BG). Currently, there is no definite cure for PD, and available treatments mainly aim to alleviate its symptoms. Due to impaired neurotransmitter-based information transmission in PD, molecular communication-based approaches can be employed as potential solutions to address this issue. Molecular Communications (MC) is a bio-inspired communication method utilizing molecules for carrying information. This mode of communication stands out for developing bio-compatible nanomachines for diagnosing and treating, particularly in addressing neurodegenerative diseases like PD, due to its compatibility with biological systems. This study presents a novel treatment method that introduces an Intelligent Dopamine Rate Modulator (IDRM), which is located in the synaptic gap between the substantia nigra pars compacta (SNc) and striatum to compensate for insufficiency dopamine release in BG caused by PD. For storing dopamine in the IDRM, dopamine compound (DAC) is swallowed and crossed through the digestive system, blood circulatory system, blood-brain barrier (BBB), and brain extracellular matrix uptakes with IDRMs. Here, the DAC concentration is calculated in these regions, revealing that the required exogenous dopamine consistently reaches IDRM. Therefore, the perpetual dopamine insufficiency in BG associated with PD can be compensated. This method reduces drug side effects because dopamine is not released in other brain regions. Unlike other treatments, this approach targets the root cause of PD rather than just reducing symptoms.
Rozita Konstantinou, Ihsan Kanbaz, Okan Yurduseven
et al.
We propose a novel approach for boosting the realized gain in enhanced directivity arrays with both active and parasitic dipoles as radiating elements. The optimization process involves two main objectives: maximizing the end-fire gain and minimizing the reflection coefficient to ensure high realized gain. In the first step, the current excitation vector of the fully driven array is selected to maximize the end-fire gain. Then, all but one of the dipoles are reactively loaded according to their input impedance. Following that, the optimization focuses on the inter-element distance, computing the one that offers a favorable balance between the gain and the total efficiency. This multi-objective optimization leverages the differential evolution (DE) algorithm and utilizes a simple wire dipole as the unit element. Full-wave simulations further confirm the accuracy of our theoretical results. Our two- and three-element parasitic arrays achieve realized gain comparable to state-of-the-art designs, without relying on intricate unit elements or resource-intensive simulations. Moreover, our four- and five-element parasitic arrays deliver the highest realized gain values reported in the literature. The simplicity of our approach is validated by significant time savings, with theoretical models completing optimizations much faster than full-wave simulations. Additionally, a sensitivity analysis confirms the robustness of the proposed optimization algorithm, demonstrating that the optimized design parameters remain effective even under small deviations in loads and element positions. Finally, the proposed parasitic arrays are well-suited for base station antennas due to their compact design, reduced power consumption, and simplified hardware requirements, making them ideal for modern communication systems.
Branko Mitic, Philipp Seeböck, Jennifer Straub
et al.
Fast detection of emerging diseases is important for containing their spread and treating patients effectively. Local anomalies are relevant, but often novel diseases involve familiar disease patterns in new spatial distributions. Therefore, established local anomaly detection approaches may fail to identify them as new. Here, we present a novel approach to detect the emergence of new disease phenotypes exhibiting distinct patterns of the spatial distribution of lesions. We first identify anomalies in lung CT data, and then compare their distribution in a continually acquired new patient cohorts with historic patient population observed over a long prior period. We evaluate how accumulated evidence collected in the stream of patients is able to detect the onset of an emerging disease. In a gram-matrix based representation derived from the intermediate layers of a three-dimensional convolutional neural network, newly emerging clusters indicate emerging diseases.
Any disease or infection that can spread spontaneously from animals to humans or humans to animals is called
zoonosis. The origin of more than 60% of human infections is zoonotic diseases. It covers many pathogens,
including bacteria, viruses, fungi, protozoa, and parasites. The emergence, distribution, and patterns of
zoonoses are significantly influenced by several factors, including climate change, animal movement, agentrelated factors, natural factors, and human impacts. Q fever has been neglected as a zoonotic disease in many
developing countries. The causative agent of this disease is the bacterium Coxiella burnetii (C. burnetii), which
is resistant to environmental factors such as heat and many disinfectant compounds, resulting in long-term risk
of disease for humans and animals. Since the infection is usually asymptomatic, it is mainly undiagnosed in
animals until adverse pregnancy outcomes occur in a herd. In humans, infection leads to severe endocarditis
and vascular infection in chronic cases. Despite the importance of this disease, limited information is available
about the molecular epidemiology and evolution of this pathogen. Genomic studies can also help to investigate
the prevalence of this disease. Likewise, the pathogenesis of C. burnetii should be examined by molecular
studies. Programs of awareness and ensuring the pasteurization of dairy products before human consumption
will help prevent many zoonotic diseases, including Q fever.
Intro: To optimise surgical outcomes and minimise the risk of infections, effective communication and teamwork are essential in the operating theatre (OT). In this pilot study, we mapped the OT team dynamics and roles in infection and safety-related practices. Methods: Between November 2021 and February 2022, data were gathered from adult surgical teams at a tertiary hospital in India. Data included direct ethnographic observations of OT activities and interactions, sociograms of targeted infection and safety-related communication, measurement of OT traffic, and focus group discussions with teams. Qualitative data were coded and analysed using a grounded theory approach. Quantitative data were analysed using descriptive statistics. Findings: Data gathered from 51 hours of direct observations across ten surgical pathways include 16 sociograms and 15 traffic-flow maps. Team hierarchies and dynamics are directly influenced by the senior surgeon. The OT staff adhere to implicitly understood roles, creating a missed opportunity for infection-related interventions. Instances of non-verbal communication are common, especially for routine activities. While the surgical and anaesthetic residents and technicians lead most tasks during procedures, the scrub nurse acts as a mediator coordinating and activating tasks among role players across hierarchies. Despite this role, the plan of events is not always communicated to them ahead of the procedure resulting in multiple door openings to source equipment and disposables. Traffic flow, counted by the number of door openings reach up to 14-15 per five minutes, with implications for infection management. Communication around the WHO checklist was limited. Conclusion: While interventions exist to optimise care in the OT, implementation challenges remain. Assigning explicit roles and responsibilities for actioning, including the WHO checklist completion, to specific team members is critical. On reflexive feedback to teams, the visual methods utilised provided an effective means for team reflection and an awareness of practices that may compromise infection management and patient safety.
Foad Alzoughool, Suhad Abumweis, Lo’ai Alanagreh
et al.
Objectives The aim of this study was to evaluate the association of pre-existing cardiovascular comorbidities, including hypertension and coronary heart disease, with coronavirus disease 2019 (COVID-19) severity and mortality. Methods PubMed, ScienceDirect, and Scopus were searched between January 1, 2020, and July 18, 2020, to identify eligible studies. Random-effect models were used to estimate the pooled event rates of pre-existing cardiovascular disease comorbidities and odds ratio (OR) with 95% confidence intervals (95% CIs) of disease severity and mortality associated with the exposures of interest. Results A total of 34 studies involving 19,156 patients with COVID-19 infection met the inclusion criteria. The prevalence of pre-existing cardiovascular disease in the included studies was 14.0%. Pre-existing cardiovascular disease in COVID-19 patients was associated with severe outcomes (OR, 4.1; 95% CI, 2.9 to 5.7) and mortality (OR, 6.1; 95% CI, 2.9 to 12.7). Hypertension and coronary heart disease increased the risk of severe outcomes by 3 times (OR, 3.2; 95% CI, 2.0 to 3.6) and 2.5 times (OR, 2.5; 95% CI, 1.7 to 3.8), respectively. No significant publication bias was indicated. Conclusion COVID-19 patients with pre-existing cardiovascular comorbidities have a higher risk of severe outcomes and mortality. Awareness of pre-existing cardiovascular comorbidity is important for the early management of COVID-19.
Special situations and conditions, Infectious and parasitic diseases
Background: The hospital environment can be an important source for the transmission of pathogens, However, there are rare reports revealing the contamination of carbapenemase-producing enterobacterales (CPE) in the hospital environment. The aim of this study was to investigate the presence of CPE in hospital environments and their relation to clinical strains. Methods: Environmental samples were collected from three tertiary university hospitals between June 2017 and August 2019. The environmental samples were inoculated on CHROMagar™ KPC plates. A multiplex PCR and sequencing were used for six carbapenemase genes. Multi-locus sequence typing (MLST) was performed for CPE of Klebsiella pneumoniae, Escherichia coli, and Enterobacter cloacae complex from the environmental and clinical specimens. Results: 20 carbapenem-resistant Enterobacteriaceae (CRE) strains were detected in the beds of patients, toilet bowl, sink, patient’s gown, electromanometer, and keyboard. K. pneumoniae was the most common, followed by Serratia marcescens, E. cloacae complex, E. coli, and Citrobacter freundii. Nineteen CRE were CPE. Eighteen of 19 CPEs produced KPC-2 carbapenemase, and one CPE (E. coli) produced NDM-5. We confirmed that the STs of K. pneumoniae-producing KPC-2 (ST 307 and ST11) and E. coli producing KPC-2 (ST648) from hospital environment were the same as those from patients. Conclusion: We believe that the hospital environment can be an important route for CPE transmission. Therefore, continuous surveillance and management are needed to prevent hospital-acquired infections (HAI) by transmission of CPE.
Infectious and parasitic diseases, Public aspects of medicine
Meningitis and meningococcal septicemia are potentially life-threatening illnesses; young people in educational institutions have been repeatedly exposed to outbreaks of meningococcal infections. Since invasive meningococcal disease is preceded by pharyngeal carriage of Neisseria meningitidis, ascertaining the prevalence of meningococcal carriage in this population is of utmost importance. The aim of this study was to determine the rate of meningococcal carriage in students of Shahid Beheshti University of Medical Sciences. This cross-sectional study was conducted on pharyngeal swab specimens of 251 healthy asymptomatic students from November 2019 for one year. A questionnaire was used to find correlation between isolation of Neisseria spp. and the place of residence, number of roommates, antibiotic use in the last month, and smoking. One sample from each student was used for culture on general and selective culture media for Neisseria spp. Polymerase chain reaction was used for the final diagnosis of Neisseria meningitidis. Participants in the study included 222 medical students (88.4%), 23 nursing students (9.2%) and 6 radiology students (2.4%). Mean (IQR1) age of students was 23 years, 134 students were female, (53.4%); 234 students were single, (93.2%). 92 students (36.7%) lived in dormitories. Neisseria were isolated from 18 specimens (7.2%), of which 11 (4.4%) were pigmented bacteria. PCR assay did not detect Neisseria meningitidis in any of the samples. This study showed that meningococcal bacteria were not detected in any of the oropharyngeal specimens from students participating in the study during the one-year study period.
In this work we study the role of parasitic interactions and microwave crosstalk in a system of two superconducting artificial atoms interacting via a single-mode coplanar waveguide. Through a general description of the effective dynamics of the atoms, beyond the two-level approximation, we show that the atom selectivity (ability to individually address an atom) is only dependent on the resultant phasor associated to the drives used to control the system. We then exploit the benefits of such a drive-dependent selectivity to describe how the coherent population inversion occurs in the atoms simultaneously, with no interference of residual atom-atom interaction. In this scenario the parasitic interaction works as a resource to fast and high fidelity control, as it gives rise to a new regime of frequencies for the atoms able to suppress effective atom-atom coupling (idling point). To end, we show how an entangling $i$SWAP gate is implemented with fidelity higher than $99\%$, even in presence of parasitic interactions. More than that, we argue that the existence of this interaction can be helpful to speed up the gate performance. Our results open prospects to a new outlook on the real role of such ``undesired" effects in a system of superconducting artificial atoms.
Kuma Diriba,1 Ephrem Awulachew,1 Gemechu Churiso2 1Department of Medical Laboratory Sciences, Health Science and Medical College, Dilla University, Dilla, Ethiopia; 2Department of Medical Laboratory Sciences, Immunology Unit, Health Science and Medical College, Dilla University, Dilla, EthiopiaCorrespondence: Kuma Diriba Tel +251913384550Email kumadiriba47@gmail.comBackground: Tuberculosis (TB) remains a major global health problem causing death among millions of people each year. The new barrier that challenges the control of tuberculosis is the emerging and the increasing number of drug-resistant TB that becomes a world concern. This study aimed to determine the magnitude of rifampicin-resistant Mycobacterium tuberculosis (RR-MTB) among presumptive TB patients attending Dilla University Referral Hospital, Gedeo Zone, Ethiopia.Methods: A retrospective cross-sectional study was conducted at Dilla University Referral Hospital from January 2014 to December 2020. Sputum results were done using Xpert MTB/RIF assay and other necessary data were collected from the registration logbooks using a standardized data extraction format and analyzed using SPSS version 23 statistical software.Results: A total of 17,745 presumptive TB patients were included, of which 62.2% were males. The overall prevalence of Mycobacterium tuberculosis (MTB) was 11.8%, of which 5.1% were confirmed to have RR-MTB. Extra-pulmonary TB was reported in 1.5% of the study participants. The highest prevalence of MTB and RR-MTB was recorded in 2017 with a prevalence of 20.1% and 8.5%, respectively. All age groups were significantly associated with a higher prevalence of MTB (p < 0.036). TB patients with a history of previous treatment and HIV positive were significantly associated with MTB (P < 0.021), while RR-MTB was only significantly associated with patients with a history of previous treatment (P < 0.018).Conclusion: A high magnitude of MTB and RR-MTB was reported among TB patients with HIV and a history of previous treatment. Therefore, coordinated efforts should be applied to the improvement of treatment adherence of known TB cases, and appropriate control and prevention methods to reduce the emergence and increase of MTB and RR-MTB cases.Keywords: presumptive TB, MTB, RR-MTB, Xpert MTB/RIF assay, previous treatment, HIV/TB
Grace D. Cullen, Tara M. Davidson, Zachary A. Yetmar
et al.
Infection is a rare cause of orbital apex syndrome (OAS) and most commonly occurs in immunocompromised hosts. We report a case of OAS in an elderly immunocompetent female due to invasive aspergillosis and Staphylococcus aureus co-infection. The patient required both surgical debridement and prolonged courses of antibiotic and antifungal therapy. Invasive fungal disease must be considered in cases of OAS, even in patients without classic risk factors.
Toxoplasmosis in humans is a zoonotic parasitic disease caused by a ubiquitous protozoan, Toxoplasma gondii. Toxoplasmosis is an opportunistic infection that can cause serious damage in immunocompromised patients. While in the non-immunocompromised individuals it is most often latent and asymptomatic, about one-third of the world’s population is estimated to be infected. Toxoplasmosis is the most common cause of posterior uveitis in non-immunocompromised individuals and the second most common cause of chorioretinitis after cytomegalovirus infection in people with HIV / AIDS. The infection can be acquired congenitally or postnatally and ocular lesions may present during or years after the occurance of the acute infection. Molecular biology techniques to diagnose ocular toxoplasmosis have been available for many years and are now accessible as standard laboratory tests in many countries. Aqueous humor or vitreous evaluation to detect parasite DNA by polymerase chain reaction or specific antibodies may provide evidence for diagnosis. Oral pyrimethamine and sulfadiazine plus corticosteroids are an effective therapy for ocular toxoplasmosis. Recent data supports the use of other treatment options, including intravitreal antibiotics. The aim of the present review is to discuss briefly the new diagnostic and treatment approaches for ocular toxoplasmosis.
Recently, [8] has proposed that heterogeneity of infectiousness (and susceptibility) across individuals in infectious diseases, plays a major role in affecting the Herd Immunity Threshold (HIT). Such heterogeneity has been observed in COVID-19 and is recognized as overdispersion (or "super-spreading"). The model of [8] suggests that super-spreaders contribute significantly to the effective reproduction factor, R, and that they are likely to get infected and immune early in the process. Consequently, under R_0 = 3 (attributed to COVID-19), the Herd Immunity Threshold (HIT) is as low as 5%, in contrast to 67% according to the traditional models [1, 2, 4, 10]. This work follows up on [8] and proposes that heterogeneity of infectiousness (susceptibility) has two "faces" whose mix affects dramatically the HIT: (1) Personal-Trait-, and (2) Event-Based- Infectiousness (Susceptibility). The former is a personal trait of specific individuals (super-spreaders) and is nullified once those individuals are immune (as in [8]). The latter is event-based (e.g cultural super-spreading events) and remains effective throughout the process, even after the super-spreaders immune. We extend [8]'s model to account for these two factors, analyze it and conclude that the HIT is very sensitive to the mix between (1) and (2), and under R_0 = 3 it can vary between 5% and 67%. Preliminary data from COVID-19 suggests that herd immunity is not reached at 5%. We address operational aspects and analyze the effects of lockdown strategies on the spread of a disease. We find that herd immunity (and HIT) is very sensitive to the lockdown type. While some lockdowns affect positively the disease blocking and increase herd immunity, others have adverse effects and reduce the herd immunity.