Neutrophil extracellular traps formation: effect of Leishmania major promastigotes and salivary gland homogenates of Phlebotomus papatasi in human neutrophil culture.

BACKGROUND: Leishmaniasis as a neglected tropical disease (NTD) is caused by the inoculation of Leishmania parasites via the bite of phlebotomine sand flies. After an infected bite, a series of innate and adaptive immune responses occurs, among which neutrophils can be mentioned as the initiators. Among the multiple functions of these fighting cells, neutrophil extracellular traps (NETs) were studied in the presence of Leishmania major promastigotes and salivary gland homogenates (SGH) of Phlebotomus papatasi alone, and in combination to mimic natural conditions of transmission. MATERIAL & METHODS: The effect of L. major and SGH on NETs formation was studied in three different groups: neutrophils + SGH (NS), neutrophils + L. major (NL), neutrophils + L. major + SGH (NLS) along with negative and positive controls in 2, 4 and 6 h post-incubation. Different microscopic methods were used to visualize NETs comprising: fluorescence microscopy by Acridine Orange/ Ethidium Bromide staining, optical microscopy by Giemsa staining and scanning electron microscopy. In addition, the expression level of three different genes NE, MPO and MMP9 was evaluated by Real-Time PCR. RESULTS: All three microscopical methods revealed similar results, as in NS group, chromatin extrusion as a sign of NETosis, was not very evident in each three time points; but, in NL and especially NLS group, more NETosis was observed and the interaction between neutrophils and promastigotes in NL and also with saliva in NLS group, gradually increased over times. Real-time reveals that, the expression of MPO, NE and MMP9 genes increased during 2 and 4 h after exposure, and then decreased at 6 h in most groups. CONCLUSION: Hence, it was determined that the simultaneous presence of parasite and saliva in NLS group has a greater impact on the formation of NETs compared to NL and NS groups.

Efficacy of Hemoperfusion in Severe and Critical Cases of COVID-19.

INTRODUCTION: Uncontrolled overproduction of inflammatory mediators is predominantly observed in patients with severe COVID-19. The excessive immune response gives rise to multiple organ dysfunction. Implementing extracorporeal therapies may be useful in omitting inflammatory mediators and supporting different organ systems. We aimed to investigate the effectiveness of hemoperfusion in combination with standard therapy in critically ill COVID-19 patients. METHOD: We conducted a single-center, matched control retrospective study on patients with confirmed SARS-CoV-2 infection. Patients were treated with hemoperfusion in combination with standard therapy (hemoperfusion group) or standard treatment (matched group). Hemoperfusion or hemoperfusion and continuous renal replacement therapies were initiated in the hemoperfusion group. The patients in the matched group were matched one by one with the hemoperfusion group for age, sex, oxygen saturation (SPO2) at the admission, and the frequency of using invasive mechanical ventilation during hospitalization. Two types of hemoperfusion cartridges used in this study were Jafron© (HA330) and CytoSorb® 300. RESULT: A total of 128 COVID-19-confirmed patients were enrolled in this study; 73 patients were allotted to the matched group and 55 patients received hemoperfusion. The median SPO2 at the admission day in the control and hemoperfusion groups was 80% and 75%, respectively (p value = 0.113). The mortality rate was significantly lower in the hemoperfusion group compared to the matched group (67.3% vs. 89%; p value = 0.002). The median length of ICU stay was statistically different in studied groups (median, 12 days for hemoperfusion group vs. 8 days for the matched group; p < 0.001). The median final SPO2 was statistically higher in the hemoperfusion group than in the matched group, and the median PaCO2 was lower. CONCLUSION: Among critically ill COVID-19 patients, based on our study, the use of hemoperfusion may reduce the mortality rate and improve SPO2 and PaCO2.

Visual transformer and deep CNN prediction of high-risk COVID-19 infected patients using fusion of CT images and clinical data.

BACKGROUND: Despite the globally reducing hospitalization rates and the much lower risks of Covid-19 mortality, accurate diagnosis of the infection stage and prediction of outcomes are clinically of interest. Advanced current technology can facilitate automating the process and help identifying those who are at higher risks of developing severe illness. This work explores and represents deep-learning-based schemes for predicting clinical outcomes in Covid-19 infected patients, using Visual Transformer and Convolutional Neural Networks (CNNs), fed with 3D data fusion of CT scan images and patients' clinical data. METHODS: We report on the efficiency of Video Swin Transformers and several CNN models fed with fusion datasets and CT scans only vs. a set of conventional classifiers fed with patients' clinical data only. A relatively large clinical dataset from 380 Covid-19 diagnosed patients was used to train/test the models. RESULTS: Results show that the 3D Video Swin Transformers fed with the fusion datasets of 64 sectional CT scans + 67 clinical labels outperformed all other approaches for predicting outcomes in Covid-19-infected patients amongst all techniques (i.e., TPR = 0.95, FPR = 0.40, F0.5 score = 0.82, AUC = 0.77, Kappa = 0.6). CONCLUSIONS: We demonstrate how the utility of our proposed novel 3D data fusion approach through concatenating CT scan images with patients' clinical data can remarkably improve the performance of the models in predicting Covid-19 infection outcomes. SIGNIFICANCE: Findings indicate possibilities of predicting the severity of outcome using patients' CT images and clinical data collected at the time of admission to hospital.

Benefit of Hemoadsorption Therapy in Patients Suffering Sepsis-Associated Acute Kidney Injury: A Case Series.

INTRODUCTION: Sepsis is defined as life-threatening organ dysfunction in result of the host's dysregulated response to infection and septic shock. Sepsis-associated kidney injury is usually defined as concurrent presence of acute kidney injury (AKI) and sepsis without other significant causative factors. METHOD: The current retrospective study was conducted to elucidate beneficial and side effects of CytoSorb®. A total of 17 patients were primarily treated with continuous renal replacement therapy in combination with CytoSorb. The demand for norepinephrine, mean arterial pressure, lactate, and procalcitonin (PCT) levels, as well as ICU length of stay, was measured. RESULT: The blood lactate levels decreased by 32.30% when comparing mean levels before and after treatment. All patients who survived (n = 14) had reduction in vasopressor demand to 68.96% of their initial dose before the start of treatment. Hospital survival was greater in patients who initially had higher vasopressor demand compared to their nonsurviving counterparts, but in whom vasopressor dosages were reduced significantly during their treatments. Mortality as predicted by APACHE II score in the overall patient population was 79.9%, whereas, the observed ICU mortality was 31%. The baseline PCT levels on patients received 1, 2, and 3 CytoSorbs were 27.08 ± 5.81 ng/mL, 13.28 ± 2.62 ng/mL, and 21.03 ± 6.56 ng/mL, respectively. Observed PCT levels at 24 h after the last treatment on patients received 1, 2, and 3 CytoSorb were 31.55 ± 15.70 ng/mL, 5.61 ± 1.77 ng/mL, and 8.11 ± 3.62 ng/mL, respectively. CONCLUSION: In conclusion, it seems that applying the CytoSorb in combination with CRRT in ICU septic patients with AKI, is related to a significant decrease in mortality, if the integrity and continuity of the treatment be kept, as much as possible. This study presented an effectively positive outcome with cytokine adsorber treatment as an adjuvant along with standard treatment in a high-risk mortality case of septic shock with organ failure.

Blood purification with CytoSorb in critically ill COVID-19 patients: A case series of 26 patients.

Severe forms of the coronavirus disease 2019 (COVID-19) can progress to sepsis-like complications accompanied by "cytokine storm" for which the most effective treatment has not yet been established. Our study describes the results of CytoSorb hemoadsorption in COVID-19 patients treated on the intensive care unit (ICU). In this retrospective study, 26 patients with COVID-19 and acute respiratory distress syndrome (ARDS) were treated with hemoadsorption therapy. Pre-, and post-treatment values (clinical and laboratory) were compared. Data are expressed as mean (confidence intervals, CI), or median [interquartile ranges, IQR], as appropriate. Patients received 2 hemoadsorption treatments. This resulted in a significant decrease in norepinephrine requirements, and inflammatory marker plasma concentrations (procalcitonin, C-reactive protein, ferritin) when comparing pre versus post treatment levels. The PaO2 /FiO2 and overall organ function (ie, Sequential Organ Failure Assessment-SOFA score) also improved significantly. Patients stayed on the ICU for 9 days and 21 of them survived. To the best of our knowledge, this is one of the largest case series to date reporting early experiences on extracorporeal hemoadsorption therapy in SARS-CoV-2 positive patients with hyperinflammation and moderate ARDS. Treatment proved to be effective, technically feasible and well-tolerated.

Antibiotic therapy in sepsis: No next time for a second chance!

WHAT IS KNOWN AND OBJECTIVE: Sepsis is a life-threatening organ dysfunction associated with a high rate of morbidity and mortality. Appropriate antibiotic therapy remains the cornerstone of sepsis and septic shock management. COMMENT: Although the early initiation of antimicrobial agents in the treatment of sepsis is widely acknowledged, the selection and adjustment to optimal dosage can be equally important. Since significant pathophysiological changes in the critically ill patients lead to altered pharmacokinetics of antibiotics, early consideration of pharmacokinetic/pharmacodynamic (PK/PD) properties is necessary for optimal antibiotic dosing in sepsis and should be integrated in practice. WHAT IS NEW AND CONCLUSION: Where possible, an individualized antibiotic dosing approach through the application of therapeutic drug monitoring (TDM) service should replace the conventional dosing in critically ill patients with sepsis. Finally, antimicrobial stewardship can help improve clinical outcomes.

Epidemiological survey on Cutaneous Leishmaniasis in southwestern Iran.

BACKGROUND & OBJECTIVES: Cutaneous leishmaniasis (CL) is still a public health threat in many rural areas of Iran. It causes considerable morbidity among a huge number of people in the endemic areas. Khuzestan is considered as a CL focus in Iran and recently several cases have been reported from Shush County. The aim of the current study was to determine different aspects of CL epidemiology in this County. METHODS: The study was conducted in four villages in the rural district of Shush County. In order to survey the scar and acute rate of the disease, 100 inhabitants were questioned in each village. In addition, to determine the reservoir host and vector of the disease, rodents were captured using Sherman traps, and sandflies were collected from around the rodent burrows using sticky paper traps. RESULTS: The scar and acute lesion rates were reported as 5.26 and 0.57% among inhabitants, respectively. Fifty-four rodents including Tatera indica (55.5%), Nesokia indica (33.3%), Mus musculus (9.3%) and Rattus norvegicus (1.9%) were captured and identified. Nested PCR showed 3 out of 54 rodents infected with Leishmania major. In total, 1122 sandflies were collected, and Leishmania major detected in Phlebotomus papatasi (4.35%), Sergentomyia dentata (23%), and Sergentomyia clydei (10%). INTERPRETATION & CONCLUSION: Zoonotic cutaneous leishmaniasis due to L. major prevailed in this area. The common and the main vector was Ph. papatasi and, T. indica seems to be the main while N. indica as a secondary reservoir host of the disease in this area.

Comparing Therapeutic Efficacy and Safety of Epoetin Beta and Epoetin Alfa in the Treatment of Anemia in End-Stage Renal Disease Hemodialysis Patients.

BACKGROUND: Anemia is one of the most prevalent complications in patients with chronic kidney disease, which is believed to be caused by the insufficient synthesis of erythropoietin by the kidney. This phase III study aimed to compare the efficacy and safety of CinnaPoietin® (epoetin beta, CinnaGen) with Eprex® (epoetin alfa, Janssen Cilag) in the treatment of anemia in ESRD hemodialysis patients. METHODS: In this randomized, active-controlled, double-blind, parallel, and non-inferiority trial, patients were randomized to receive either CinnaPoietin® or Eprex® for a 26-week period. The primary endpoints of this study were to assess the mean hemoglobin (Hb) change during the last 4 weeks of treatment from baseline along with the evaluation of the mean weekly epoetin dosage per kilogram of body weight that was necessary to maintain the Hb level within 10-12 g/dL during the last 4 weeks of treatment. As the secondary objective, safety was assessed along with other efficacy endpoints. RESULTS: A total of 156 patients were included in this clinical trial. There was no statistically significant difference between treatment groups regarding the mean Hb change (p = 0.21). In addition, the mean weekly epoetin dosage per kg of body weight for maintaining the Hb level within 10-12 g/dL showed no statistically significant difference between treatment arms (p = 0.63). Moreover, both products had comparable safety profiles. However, the incidence of Hb levels above 13 g/dL was significantly lower in the CinnaPoietin® group. CONCLUSION: CinnaPoietin® was proved to be non-inferior to Eprex® in the treatment of anemia in ESRD hemodialysis patients. The trial was registered in Clinicaltrials.gov (NCT03408639).

Susceptibility status of wild population of Phlebotomus sergenti (Diptera: Psychodidae) to different imagicides in a endemic focus of cutaneous leishmaniasis in northeast of Iran.

BACKGROUND & OBJECTIVES: Phlebotomine sandflies (Diptera: Psychodidae) transmit several important zoonotic diseases to humans and leishmaniasis is one of them. Two types of leishmaniasis, viz. visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) are endemic in Iran. The main vector of anthroponotic cutaneous leishmaniasis (ACL) is Phlebotomus sergenti. The aim of the present study was to determine the susceptibility status of wild strain of P. sergenti to different imagicides of DDT, bendiocarb and permethrin at the median lethal time, LT50 level. METHODS: Sandflies were collected from selected village in North Khorasan Province, northeast of Iran from indoors using CDC light-traps. Susceptibility test was carried out against DDT (4%), bendiocarb (0.1%) and permethrin (0.75%) for all the females according to WHO method, and mortality was calculated. Species identification was carried out using the morphological keys. Data were analysed using probit regression analysis to determine the LT50 and LT90 values. RESULTS: In total, 851 female P. sergenti sandflies were tested. LT50 values to DDT (4%), Bendiocarb (0.1%) and permethrin (0.75%) were 15.4, 19.2 and 6.3 min respectively. The values for LT90 were 51.1, 47.4 and 18.6 min respectively. The mortality rates for 1 h exposure time to DDT, bendiocarb and permethrin were 89.8 ± 1.4; 93.6 ± 1.4; and 95.6 ± 1.7%, respectively. INTERPRETATION & CONCLUSION: The suscesptibility studies revealed development of resistance against DDT (4%) in the wild strain of P. sergenti population. Monitoring and mapping of insecticide resistance in the region is recommended for vector control.

Anti Leishmania activity of Lucilia sericata and Calliphora vicina maggots in laboratory models.

Use of sterile fly larvae (maggots) of blow flies for the treatment of many different types of skin and soft tissue wounds is called Maggot debridement therapy (MDT). The larvae of blow flies secrete a broad spectrum of compounds with diverse mechanisms of action in the gut and salivary glands called excretion/secretion (ES) products which showed to have antimicrobial activities against Gram negative and positive bacteria. Cutaneous leishmaniasis (CL) which is the common form of leishmaniasis is difficult to treat. In this study, the effect of ES from 2nd and 3rd stages of L. sericata and C. vicina larvae on in vitro Leishmania major amastigote growth in macrophage was evaluated. The effect of ES on Leishmania growth was estimated by assessing the rate of macrophage infection and the number of amastigotes per infected macrophages. In addition, the anti Leishmania activities of larval and ES of L. sericata and C. vicina on the skin lesion induced by L. major infection was evaluated in susceptible BALB/c mice. The results showed that ES of both flies reduced the number of infected macrophages; 2.6 and 1.5-fold using L. sericata ES and C. vicina ES, respectively, and inhibited amastigotes growth in macrophages; 2.03 and 1.36-fold by L. sericata ES and C. vicina ES, respectively as compared to the control group. The results showed that L. sericata ES was significantly more effective than C. vicina ES to inhibit in vitro L. major amastigotes growth, The size of lesion was significantly smaller in BALB/c mice treated with L. sericata ES than treated with C. vicina ES. The results of in vivo experiments suggested that pre-treatment with ES derived from L. sericata may have some protective effects on the development of L. major lesion. Therefore, it seems that maggot ES might be considered as a possible candidate for the treatment of cutaneous leishmaniasis.

Bioassay evaluation of residual activity of attractive toxic sugar-treated barrier fence in the control of Phlebotomus papatasi (Diptera: Psychodidae).

BACKGROUND & OBJECTIVES: Phlebotomus papatasi is the main vector of the zoonotic cutaneous leishmaniasis (ZCL) in Qom Province and many other provinces of Iran. Attractive toxic sugar baits (ATSB) treated barrier fence is one of the new methods for controlling the vectors such as sandflies. The present study was designed to evaluate the residual activity of ATSB-treated barrier fence that was used in control of P. papatasi. METHODS: Following the selection of villages in Markazi district of Qom Province, central Iran during 2015 for ATSB and ASB (bait containing no active ingredient) methods; barrier fences on the ground in front of the rodent's colony were installed. A total of four conical tubes were installed and fixed on surfaces of treated barrier net of dimension 25 Χ 25 cm at biweekly interval. In each conical tube, 10 sand flies were released and after 3 min of exposure they were transferred to sterile cups. After 24 h, the obtained results were recorded according to the survival and mortality rate of sandflies. These tests were carried out five days after the installation of barrier fences, and repeated every 15 days until the mortality rate decreased to 60-65%. RESULTS: The bioassay tests results showed that the mortality rate of P. papatasi on ATSB-treated barrier fence for 5, 15, 30 and 45 days after spraying was 100, 95.83, 88.18 and 66.67% respectively, which decreased to 50.83% after 60 days. INTERPRETATION & CONCLUSION: Persistence and residual activity of the active ingredient of the bait in the hot and dry climatic conditions of Qom Province remained significantly effective for at most 45 days, which subsequently decreased at a high rate. Hence, every 45 days barrier fences need to be impregnated with ATSB bait. The method also appeared cost-effective and could be practical in implementation of vector control programmes against ZCL.

Modeling the Distribution of Cutaneous Leishmaniasis Vectors (Psychodidae: Phlebotominae) in Iran: A Potential Transmission in Disease Prone Areas.

Cutaneous leishmaniasis (CL) is now the main vector-borne disease in Iran. Two forms of the disease exist in the country, transmitted by Phlebotomus papatasi and Phlebotomus sergenti s.l. Modeling distribution of the vector species is beneficial for preparedness and planning to interrupt the transmission cycle. Data on sand fly distribution during 1990-2013 were used to predict the niche suitability. MaxEnt algorithm model was used for prediction using bioclimatic and environmental variables (precipitation, temperature, altitude, slope, and aspect). Regularized training, area under the curve, and unregularized training gains were 0.916, 0.915, and 1.503, respectively, for Ph. papatasi. These values were calculated as 0.987, 0.923, and 1.588 for Ph. sergenti s.l. The jackknife test showed that the environmental variable with the highest gain when used in isolation has the mean temperature of the wettest quarter for both species, while slope decreases the gain the most when it is omitted from the model. Classification of probability of presence for two studied species was performed on five classes using equal intervals in ArcGIS. More than 60% probability of presence was considered as areas with high potential of CL transmission. These areas include arid and semiarid climates, mainly located in central part of the country. Mean of altitude, annual precipitation, and temperature in these areas were calculated 990 and 1,235 m, 273 and 226 mm, and 17.5 and 16.4°C for Ph. papatasi and Ph. sergenti s.l., respectively. These findings can be used in the prediction of CL transmission potential, as well as for planning the disease control interventions.

Effectiveness of a clinical protocol implemented to standardize snakebite management in Iran: initial evaluation.

OBJECTIVE: This study was designed to evaluate the effectiveness of a new protocol implemented to standardize snakebite management in Iran. METHODS: In this study, 27 patients treated according to the new protocol in 2012 (P+) were compared with 22 patients treated according to the previous modality in the year before implementation of the protocol (P-) in Mashhad Medical Toxicology Centre (MTC). Demographic characteristics and treatment details of all patients were recorded prospectively. Envenomation severity of each victim was assessed according to snakebite severity score (SSS). RESULTS: After implementation of the protocol, a smaller percentage of patients received antivenom (AV) therapy (78% vs 95%; P=.079). In spite of no significant difference in baseline severity of envenomation between the 2 groups (SSS [mean±SD], 34.8±18.1 vs 35.5±17.4; P=.801), the P+ group received significantly fewer AV vials (8.4±6.8 vs 12.1±5.6 vials; P=.042) and had a significantly shorter length of hospital stay (2.2±1.5 vs 3.2±1.8 days; P=.027). Moreover, smaller proportion of P+ patients experienced recurrence of venom-induced effects; however, the difference was not significant (18.5% vs 36%; P=.159). The reduction in use of antiallergy treatments to prevent or treat acute hypersensitivity reactions approached statistical significance (41% vs 68%; P=.051). These findings denote a reduction in AV use of approximately 4 vials and a reduction in hospital stay of 1 day for each patient, which translates to approximately $196/patient in healthcare cost savings. CONCLUSIONS: Implementation of a snakebite management protocol at MTC reduced overall antivenom usage, use of antiallergy interventions, and length of hospital stay.

Synthesis and in vitro study of cisplatin-loaded Fe3O4 nanoparticles modified with PLGA-PEG6000 copolymers in treatment of lung cancer.

In the field of cancer therapy, magnetic nanoparticles modified with biocompatible copolymers are promising vehicles for the delivery of hydrophobic drugs such as Cisplatin. The major aim of this effort was to evaluate whether Cisplatin-Encapsulated magnetic nanoparticles improved the anti-tumour effect of free Cisplatin in lung cancer cells. The PLGA-PEG triblock copolymer was synthesised by ring-opening polymerisation of d,l-lactide and glycolide with polyethylene glycol (PEG6000) as an initiator. The bulk properties of these copolymers were characterised using Fourier transform infrared spectroscopy. Cisplatin-loaded nanoparticles (NPs) were prepared by double emulsion solvent evaporation technique and were characterised for size, drug entrapment efficiency (%), drug content (% w/w), and surface morphology. In vitro release profile of cisplatin-loaded NP formulations was determined. Cytotoxic assays were evaluated in lung carcinoma (A549)-treated cells by the MTT assay technique. In addition, the particles were characterised by X-ray powder diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. The anti-proliferative effect of Cisplatin appeared much earlier when the drug was encapsulated in magnetic nanoparticles than when it was free. Cisplatin-Encapsulated magnetic nanoparticles significantly enhanced the decrease in IC50 rate. The in vitro cytotoxicity test showed that the Fe3O4-PLGA-PEG6000 magnetic nanoparticles had no cytotoxicity and were biocompatible. The chemotherapeutic effect of free Cisplatin on lung cancer cells is improved by its encapsulation in modified magnetic nanoparticles. This approach has the prospective to overcome some major limitations of conventional chemotherapy and may be a promising strategy for future applications in lung cancer therapy.

Giant Coronary Artery Aneurysm Due to Implantation of Drug-Eluting Stent.

Development of coronary artery aneurysm after implantation of a drug-eluting stent is a rare complication. The mechanism behind aneurysm formation is unknown, but studies suggest hypersensitivity and inflammatory reactions elicited by the stent polymer. Here, we report a case of a 57-year-old man who was treated with a sirolimus-eluting CypherTM stent in the left anterior descending artery due to stable angina pectoris and left circumflex artery due to dissection. Coronary aneurysm formation at the site of stent implantation was discovered three years after the stents were deployed, and progression of the aneurysms was seen in the coronary artery angiography. We hypothesize about the mechanism of aneurysm formation and present management of the aneurysms.

Metabolic health's central role in chronic kidney disease progression: a 20-year study of obesity-metabolic phenotype transitions.

This study investigates the risk of chronic kidney disease (CKD) across four metabolic phenotypes: Metabolically Healthy-No Obesity (MH-NO), Metabolically Unhealthy-No obesity (MU-NO), Metabolically Healthy-Obesity (MH-O), and Metabolically Unhealthy-Obesity (MU-O). Data from the Tehran Lipid and Glucose Study, collected from 1999 to 2020, were used to categorize participants based on a BMI ≥ 30 kg/m2 and metabolic health status, defined by the presence of three or four of the following components: high blood pressure, elevated triglycerides, low high-density lipoprotein, and high fasting blood sugar. CKD, characterized by a glomerular filtration rate < 60 ml/min/1.72 m2. The hazard ratio (HR) of CKD risk was evaluated using Cox proportional hazard models. The study included 8731 participants, with an average age of 39.93 years, and identified 734 incidents of CKD. After adjusting for covariates, the MU-O group demonstrated the highest risk of CKD progression (HR 1.42-1.87), followed by the MU-NO group (HR 1.33-1.67), and the MH-O group (HR 1.18-1.54). Persistent MU-NO and MU-O posed the highest CKD risk compared to transitional states, highlighting the significance of exposure during early adulthood. These findings emphasize the independent contributions of excess weight and metabolic health, along with its components, to CKD risk. Therefore, preventive strategies should prioritize interventions during early-adulthood.

Association Between Wolbachia Infection and Susceptibility to Deltamethrin Insecticide in Phlebotomus papatasi (Diptera: Psychodidae), the Main Vector of Zoonotic Cutaneous Leishmaniasis.

Background: Phlebotomus papatasi (Diptera: Psychodidae) is the main vector of zoonotic cutaneous leishmaniasis. Wolbachia is a symbiotic alphaproteobacteria of arthropods that can be involved in susceptibility or resistance. This study aimed to investigate the relationship between Wolbachia and Deltamethrin susceptibility/resistance in Ph. papatasi. Deltamethrin filter papers (0.00002%) were used to test sand fly field collected from southern Iran. After the test, PCR amplification of the Wolbachia surface protein gene (wsp) was used to measure Wolbachia infection rate in the killed, surviving, and control groups. Result: The rates of infection by Wolbachia strain (wPap, super group A) differed between killed (susceptible) and surviving (resistant) Ph. papatasi specimens. The rate of Wolbachia infection in susceptible individuals was more than twice (2.3) (39% vs. 17%) in resistant individuals with the same genetic background. This difference was highly significant (p < 0.001), indicating a positive association between Wolbachia infection and susceptibility to Deltamethrin. In addition, the results showed that Deltamethrin can act as a PCR inhibitor during detection of Wolbachia in Ph. papatasi. Conclusion: Results of this study show that Wolbachia is associated with Deltamethrin susceptibility level in Ph. papatasi. Also, as Deltamethrin has been identified as a PCR inhibitor, great care must be taken in interpreting Wolbachia infection status in infected populations. The results of this study may provide information for a better understanding of the host-symbiont relationship, as well as application of host symbiosis in pest management.

Assessing Survival of Transgenic Bacteria, Serratia AS1 and Enterobacter cloacae, in Sugar Bait, White Saxaul Plant (Haloxylon persicum) and Rodent Barrow's Soil, A Contained-Field Study for Paratransgenesis Approach.

Background: The viability and persistence of engineered bacterium candidates in field conditions is one of the considerable challenges in the paratransgenesis approach to fighting vector-borne diseases. Methods: In this study two engineered bacterium candidates to produce paratransgenic sand flies, Serratia AS1 and Enterobacter cloacae expressing m-Cherry fluorescent were applied on the leaves of the white saxaul plant (Haloxylon persicum), sugar bait, and rodent burrow soil and their persistent time was tested in desert condition, Matin Abad County, Isfahan, August 2022. A PBS suspension of 109 cells/ml was used for sugar bait, spraying on plant leaves (∼10 cm2) and 10 cm2 of rodent burrow soil. Sand fly samples were taken daily and were plated on LB Agar and the fluorescent cells were counted after 24 hours. Results: Time course in general caused a decrease in the number of bacteria for both strains. The two strains were persistent in sugar bait and on plant leaves for four days and on soil for two days. Although there were slight differences between the number of the bacteria in sugar baits, which was not significant (P< 0.05). The number of E. cloacae surviving on plant and in soil were significantly (P< 0.0001 and P= 0.046) higher than Serratia AS1. Conclusion: This study shows that plants or sugar bait are useful routes for delivery of the transformed bacteria for the paratransgenesis approach, although, the bacteria ought to be sprayed on plants or sugar baits should be replaced with new ones in four days intervals.