Engorgement Rates Research Articles

Usefulness of Antigen Carbohydrate 125 and N-Terminal Pro-B-Type Natriuretic Peptide for Assessing Congestion in Chronic Heart Failure: Insights from the CARDIOREN Registry

Introduction: A comprehensive assessment of congestion, including circulating biomarkers, is recommended in patients with acute heart failure. The circulating biomarkers natriuretic peptides (NPs) and carbohydrate antigen-125 (CA125) could be useful for congestion assessment in ambulatory chronic heart failure (CHF), but there is only limited information about their applicability in this context. Therefore, this study aimed to examine the association of plasma CA125 and NP levels with clinical and ultrasound congestion parameters in CHF. Methods: This is a cross-sectional substudy of the Cardioren Spanish Registry, which enrolled 1,107 patients with CHF from 13 tertiary hospitals in Spain between October 2021 and February 2022. Through ambulatory visits, we performed a comprehensive assessment of congestion-related parameters, including clinical variables (orthopnea, peripheral edema, and jugular engorgement, represented by the composite congestion score [CCS]), echocardiography variables (lung B-lines and inferior vena cava [IVC] diameter), and circulating biomarkers (CA125 and NPs). The association of the NP and CA125 levels with the clinical and echocardiographic congestion parameters was examined by multiple linear and logistic regression analyses. Results: This substudy included 802 patients for whom all the biomarker parameters were available {median age, 74 (interquartile range [IQR], 63–81) years; 65% male}. The proportion of patients with left ventricular ejection fraction ≥50% and estimated glomerular filtration rate <60 was 34% and 58%, respectively. The median CCS was 0 (IQR: 0–1), with 45% of the sample exhibiting a median CCS of ≥1. The jugular engorgement, peripheral edema, and orthopnea rates were 32%, 21%, and 21%, respectively. A total of 35% of patients who underwent ultrasound examination showed lung B-lines, and the median IVC diameter was 16 mm. The median CA125 and NTproBNP levels were 14 U/mL (IQR: 9–28) and 1,382 pg/mL (IQR: 563–3,219), respectively. Multivariate analysis showed that higher CA125 levels were independently associated with higher odds of peripheral edema (p = 0.023) and lung B-lines (p < 0.001). Further, NTproBNP was positively associated with jugular engorgement (p < 0.001), orthopnea (p = 0.034), and enlarged IVC diameter (p = 0.031). Conclusions: Clinical signs of congestion are frequent in CHF. In the ambulatory setting, NTproBNP was associated with parameters linked to intravascular congestion such as orthopnea, jugular engorgement, and IVC diameter, whereas CA125 was associated with extravascular volume overload parameters (peripheral edema and lung B-lines).

Efficacy of sugar‐protein non‐membranous dietary system for diapause egg production in Aedes albopictus mosquitoes under short‐day conditions

AbstractThe Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae), is a global vector of dengue, chikungunya and zika viruses. With extreme adaptability of survival as diapause eggs, this mosquito has invaded and established in temperate climatic zones. The diapause eggs are specially programmed to overcome the harsh winter conditions in temperate habitats. In the laboratory, diapausing females are reared from early larval instars under short‐day conditions (21°C and 16D:8 L photoperiods). Aedes albopictus is normally fed on Guinea pigs for the rearing of diapause mosquitoes which requires ethical approval from the animal use committee and costly arrangements. Therefore, the present study was conducted to find whether bovine serum albumin protein (10%) with sucrose (5%) solution (SAP‐10) offered through a membrane‐free feeding system would result in an alternative diet for the production of diapause eggs in comparison to blood‐feeding. This feeding system shows a considerable rate of engorgement of diapausing females under short‐day conditions and produced 30.8 diapause eggs/female in comparison to blood‐feeding on a guinea pig (40.9 eggs/female). The diapause rate of viable eggs for the SAP‐10 diet (95.28%) was similar to the blood‐feeding (96.32%). The findings suggest that the present diet feeding system is a promising tool for the rearing of diapause Ae. albopictus mosquitoes under short‐day conditions. Further studies are suggested to evaluate the physiological and developmental aspects of mosquitoes reared on the diet.

Infectivity of Plasmodium parasites to Aedes aegypti and Anopheles stephensi mosquitoes maintained on blood-free meals of SkitoSnack

BackgroundAedes and Anopheles mosquitoes are responsible for tremendous global health burdens from their transmission of pathogens causing malaria, lymphatic filariasis, dengue, and yellow fever. Innovative vector control strategies will help to reduce the prevalence of these diseases. Mass rearing of mosquitoes for research and support of these strategies presently depends on meals of vertebrate blood, which is subject to acquisition, handling, and storage issues. Various blood-free replacements have been formulated for these mosquitoes, but none of these replacements are in wide use, and little is known about their potential impact on competence of the mosquitoes for Plasmodium infection.MethodsColonies of Aedes aegypti and Anopheles stephensi were continuously maintained on a blood-free replacement (SkitoSnack; SS) or bovine blood (BB) and monitored for engorgement and hatch rates. Infections of Ae. aegypti and An. stephensi were assessed with Plasmodium gallinaceum and P. falciparum, respectively.ResultsReplicate colonies of mosquitoes were maintained on BB or SS for 10 generations of Ae. aegypti and more than 63 generations of An. stephensi. The odds of engorgement by SS- relative to BB-maintained mosquitoes were higher for both Ae. aegypti (OR = 2.6, 95% CI 1.3–5.2) and An. stephensi (OR 2.7, 95% CI 1.4–5.5), while lower odds of hatching were found for eggs from the SS-maintained mosquitoes of both species (Ae. aegypti OR = 0.40, 95% CI 0.26–0.62; An. stephensi OR = 0.59, 95% CI 0.36–0.96). Oocyst counts were similar for P. gallinaceum infections of Ae. aegypti mosquitoes maintained on SS or BB (mean ratio = [mean on SS]/[mean on BB] = 1.11, 95% CI 0.85–1.49). Similar oocyst counts were also observed from the P. falciparum infections of SS- or BB-maintained An. stephensi (mean ratio = 0.76, 95% CI 0.44–1.37). The average counts of sporozoites/mosquito showed no evidence of reductions in the SS-maintained relative to BB-maintained mosquitoes of both species.ConclusionsAedes aegypti and An. stephensi can be reliably maintained on SS over multiple generations and are as competent for Plasmodium infection as mosquitoes maintained on BB. Use of SS alleviates the need to acquire and preserve blood for mosquito husbandry and may support new initiatives in fundamental and applied research, including novel manipulations of midgut microbiota and factors important to the mosquito life cycle and pathogen susceptibility.Graphical

An optimized artificial blood feeding assay to study tick cuticle biology

Ticks, ectoparasitic arachnids, are prominent disease vectors impacting both humans and animals. Their unique blood-feeding phase involves significant abdominal cuticle expansion, sharing certain similarities with insects. However, vital aspects, including the mechanisms of cuticle expansion, changes in cuticular protein composition, chitin synthesis, and cuticle function, remain poorly understood. Given that the cuticle expansion is crucial for complete engorgement of the ticks, addressing these knowledge gaps is essential. Traditional tick research involving live animal hosts has inherent limitations, such as ethical concerns and host response variability. Artificial membrane feeding systems provide an alternative approach, offering controlled experimental conditions and reduced ethical dilemmas. These systems enable precise monitoring of tick attachment, feeding parameters, and pathogen acquisition. Despite the existence of various methodologies for artificial tick-feeding systems, there is a pressing need to enhance their reproducibility and effectiveness. In this context, we introduce an improved tick-feeding system that incorporates adjustments related to factors like humidity, temperature, and blood-feeding duration. These refinements markedly boost tick engorgement rates, presenting a valuable tool for in-depth investigations into tick cuticle biology and facilitating studies on molting. This refined system allows for collecting feeding ticks at specific stages, supporting research on tick cuticle biology, and evaluating chemical agents' efficacy in the engorgement process.

New artificial hematophagy system with attractive polymeric biofilm for maintenance of Culex quinquefasciatus (Diptera: Culicidae) in the laboratory

BackgroundMaintaining mosquito colonies in the laboratory requires a blood supply so that females' oocytes can mature and oviposition can take place. In this study, a new artificial hematophagy system for colonization and maintenance of Culex quinquefasciatus in the laboratory was developed and tested.MethodsWe developed an attractive polymeric biofilm including 25% l-lactic acid for use as a membrane in an artificial hematophagy system and compared the feeding rate of females with Parafilm-M®. We also evaluated the oviposition rate, larval survival and adult emergence of females fed through the attractive biofilm.ResultsThe average percentage of female Cx. quinquefasciatus fed through the attractive biofilm was 87%, while only 20% became engorged with Parafilm-M® (p < 0.0001). Feeding through the attractive biofilm developed in this study produced high levels of evaluated biological parameters; the percentage of egg laying by females that underwent artificial hematophagy through the biofilm was 90%, with an average of 158 eggs per raft. From these eggs, 97% of the larvae hatched, of which 95% reached the pupal stage. The adult emergence rate corresponded to 93% of pupae.ConclusionsInsects fed with attractant through the biofilm system had a higher engorgement rate compared to those fed through Parafilm-M®. Our study is preliminary and suggests that polymeric biofilm has great potential for artificially feeding mosquitoes in the laboratory. Based on this research, new studies will be carried out with biofilm and different systems.Graphical

Potential roles of Culicoides spp. (Culicoides imicola, Culicoides oxystoma) as biological vectors of bluetongue virus in Yuanyang of Yunnan, P. R. China.

Culicoides plays a crucial role as an insect vector in the field of veterinary medicine. The transmission of significant viruses such as bluetongue virus (BTV) and African horse sickness virus (AHSV) by this insect poses a substantial threat, leading to the development of severe diseases in domestic animals. This study aimed to explore the Culicoides species, identify their blood-meal sources, and assess the presence of BTV and AHSV carried by Culicoides in Yuanyang County, Yunnan Province. The aim was to gain insights into the potential vectors of these two viruses and elucidate their potential roles in the transmission of pathogens. The midges were collected from cattle (Bos indicus), pig (Sus scrofa), and goat (Capra hircus) pens in Yuanyang County, Yunnan Province in June 2020. Initial identification of midges was conducted through morphological characteristics, followed by molecular identification using the cytochrome C oxidase subunit I (COI) gene. The determination of Culicoides blood-meal sources was accomplished using specific primers targeting the cytochrome b (Cyt b) gene from potential hosts. BTV and AHSV RNA were identified in Culicoides pools through the application of reverse transcriptase PCR and quantitative real-time PCR. Nucleotide homology and phylogenetic analysis were performed using MegAlign (DNAStar) and Mega 6.0 software. A total of 6,300 Culicoides, consisting of C. oxystoma, C. arakawai, C. imicola, and C. innoxius, were collected from cattle, pigs, and goat pens. The engorgement rates for these species were 30.2%, 54.6%, 75%, and 66.7%, respectively. In the cattle pen, the prevailing species is C. oxystoma (100%). In the pig pen, C. arakawai dominates (70%), with C. oxystoma following at 30%. In the goat pen, C. imicola holds the majority (45.45%), trailed by C. oxystoma (25%), C. innoxius (20.45%), and C. arakawai (9.09%). These Culicoides species were identified as feeding on cattle, pigs, goats, chickens (Gallus gallus), and humans (Homo sapiens). The positivity rates for BTV were 20.00% and 11.54% in blood-fed specimens of C. imicola and C. oxystoma, respectively. Conversely, the positivity rates for BTV in non-blood-fed specimens were 0.00% and 6.67% for C. imicola and C. oxystoma, respectively. BTV was not detected in C. arakawai and C. innoxius. The specimens (YY86) from C. imicola that tested positive for BTV had the closest genetic relationship to YTS-4 isolated from Mangshi, Yunnan Province in 1996. All test results for the nucleic acid of AHSV were negative. The study reveals variations in the species distribution, community composition, blood sucking rate, and blood-feeding sources of Culicoides across different habitats. Notably, C. imicola and C. oxystoma emerge as potential vectors for the transmission of BTV in local animals. Accordingly, this investigation provides crucial insights that can serve as a valuable reference for the prevention and control of BTV in local animals, particularly from the perspective of vector management.

In vitro feeding of all life stages of two-host Hyalomma excavatum and Hyalomma scupense and three-host Hyalomma dromedarii ticks

Ticks are blood-sucking ectoparasites and can transmit various pathogens of medical and veterinary relevance. The life cycle of ticks can be completed under laboratory conditions on experimental animals, but the artificial feeding of ticks has attracted increased interest as an alternative method. This study represents the first report on the successful in vitro feeding of all life stages of two-host tick species, Hyalomma scupense and Hyalomma excavatum, and the three-host tick Hyalomma dromedarii. The attachment and engorgement rates of adults were 84% (21/25) and 76% (19/25) for H. scupense females. For adult H. excavatum and H. dromedarii, 70% (21/30) and 34.4% (11/32) of the females attached and all attached females successfully fed to repletion. The oviposition rates of the artificially fed females were 36.4%, 57.1% and 63.1% for H. dromedarii, H. excavatum and H. scupense, respectively, with a reproductive efficiency index varying between 44.3 and 60.7%. For the larvae, the attachment and engorgement rates were 44.2% (313/708) and 42.8% (303/708) for H. dromedarii, 70.5% (129/183) and 56.8% (104/183) for H. excavatum and 92.6% (113/122) and 55.7% (68/122) for H. scupense. The attachment and engorgement rates for the nymphs were 90.2% (129/143) and 47.6% (68/143) for H. dromedarii, 66.7% (34/51) and 41.2% (21/51) for H. excavatum, and 44.1% (30/68) and 36.8% (25/68) for H. scupense. Molting rates of the immature stages varied between 71.3% (216/303) and 100% (68/68) for the larvae and between 61.9% (13/21) and 96% (24/25) for the nymphs. The successful in vitro feeding of all stages of the three Hyalomma species makes this method a valuable tool for tick research, with potential applications in studies on the pathogens transmitted by these tick species such as Theileria annulata.

Efficacy of recombinant enolase as a candidate vaccine against Haemaphysalis longicornis tick infestation in mice.

Tick infestation causes a significant threat to human and animal health, requiring effective immunological control methods. This study aimed to investigate the potential of recombinant Haemaphysalis longicornis enolase protein for tick vaccine development. The exact mechanism of the recently identified enolase protein from the H. longicornis Jeju strain remains poorly understood. Enolase plays a crucial role in glycolysis, the metabolic process that converts glucose into energy, and is essential for the motility, adhesion, invasion, growth, and differentiation of ticks. In this study, mice were immunized with recombinant enolase, and polyclonal antibodies were generated. Western blot analysis confirmed the specific recognition of enolase by the antiserum. The effects of immunization on tick feeding and attachment were assessed. Adult ticks attached to the recombinant enolase-immunized mice demonstrated longer attachment time, increased blood-sucking abilities, and lower engorgement weight than the controls. The nymphs and larvae had a reduced attachment rate and low engorgement rate compared to the controls. Mice immunized with recombinant enolase expressed in Escherichia coli displayed 90% efficacy in preventing tick infestation. The glycolytic nature of enolase and its involvement in crucial physiological processes makes it an attractive target for disrupting tick survival and disease transmission. Polyclonal antibodies recognize enolase and significantly reduce attachment rates, tick feeding, and engorgement. Our findings indicate that recombinant enolase may be a valuable vaccine candidate for H. longicornis infection in experimental murine model.

Evaluation of "Caserotek" a low cost and effective artificial blood-feeding device for mosquitoes.

Entomological research studies on mosquito vector biology, vector competence, insecticide resistance, dispersal, and survival (using mark-release-recapture techniques) often rely on laboratory-reared mosquito colonies to produce large numbers of consistently reared, aged, and sized mosquitoes. We developed a low-cost blood feeding apparatus that supports temperatures consistent with warm blooded animals, using commonly available materials found in low resource environments. We compare our system ("Caserotek") to Hemotek and glass/membrane feeding methods. Two experiments were conducted with Aedes aegypti (Linnaeus 1762) and one with Anopheles darlingi (Root 1926) (Diptera: Culicidae); 3 replicates were conducted for each experiment. Aedes aegypti female mosquitoes were provided chicken blood once per week for 30 min (Experiment #1) for 14 days or 1 hour (Experiment #2) for 21 days. Anopheles darlingi were fed once for 1 hour (Experiment #3). Blood-feeding rates, survival rates, and egg production were calculated across replicates. Caserotek had a significantly higher 30-min engorgement rate (91.1%) than Hemotek (47.7%), and the glass feeder (29.3%) whereas for 1-hour feeding, Hemotek had a significantly lower engorgement rate than either of the other two devices (78% versus 91%). Thirty-day survival was similar among the feeding devices, ranging from 86% to 99%. Mean egg production was highest for the Caserotek feeder (32 eggs per female) compared to the glass feeder and Hemotek device (21-22 eggs per female). Our new artificial feeding system had significantly higher blood feeding rates than for more expensive artificial systems and was equivalent to other fitness parameters. Caserotek only requires the ability to boil water to maintain blood temperatures using a Styrofoam liner. It can be easily scaled up to large production facilities and used under austere conditions.

A simple non-invasive method to collect soft tick saliva reveals differences in Ornithodoros moubata saliva composition between ticks infected and uninfected with Borrelia duttonii spirochetes.

Introduction: We developed a new simple method to assess the composition of proteinaceous components in the saliva of Ornithodoros moubata, the main vehicle for pathogen transmission and a likely source of bioactive molecules acting at the tick-vertebrate host interface. To collect naturally expectorated saliva from the ticks we employed an artificial membrane feeding technique using a simple, chemically defined diet containing phagostimulants and submitted native saliva samples collected in this way for liquid chromatography-mass spectrometry (LC-MS) analysis. These experiments were conducted with groups of uninfected ticks as well as with O. moubata infected with B. duttonii. The ticks exhibited a fair feeding response to the tested diet with engorgement rates reaching as high as 60-100% of ticks per feeding chamber. The LC-MS analysis identified a total of 17 and 15 proteins in saliva samples from the uninfected and infected O. moubata nymphs, respectively. Importantly, the analysis was sensitive enough to detect up to 9 different proteins in the samples of saliva containing diet upon which as few as 6 nymphal ticks fed during the experiments. Some of the proteins recognized in the analysis are well known for their immunomodulatory activity in a vertebrate host, whereas others are primarily thought of as structural or "housekeeping" proteins and their finding in the naturally expectorated tick saliva confirms that they can be secreted and might serve some functions at the tick-host interface. Most notably, some of the proteins that have long been suspected for their importance in the vector-pathogen interactions of Borrelia spirochetes were detected only in the samples from infected ticks, suggesting that their expression was altered by the persistent colonization of the tick's salivary glands by spirochetes. The simple method described herein is an important addition to the toolbox available to study the vector-host-pathogen interactions in the rapidly feeding soft ticks.

Sugar Bait Composition Containing Ivermectin Affect Engorgement and Mortality of the Mosquito Aedes aegypti (Diptera: Culicidae).

Toxins and attractants have been studied and used in sugar baits for mosquitoes. However, little importance has been given to the combination of sugar concentration, bait composition, and their relationship with mosquito engorgement and mortality. Therefore, the present study evaluated the effects of three concentrations of sucrose on baits with and without an attractant (concentrated guava juice), on engorgement and mortality rates of adult Aedes aegypti (Linnaeus, Diptera: Culicidae). Toxic sugar baits (TSB) and attractant toxic sugar baits (ATSB) containing 10, 50, and 70% sucrose and 100 ppm ivermectin (IVM) were prepared to assess engorgement and mortality rates. Subsequently, different concentrations of IVM (0.312-100 ppm) in TSB and ATSB were prepared with sucrose concentrations of 10 and 70% to determine the lethal concentrations (LC50 and LC90) values. Engorgement on the baits was observed under a stereomicroscope, and mortality was followed up to 48 h after feeding. In general, more mosquitoes engorged on TSB regardless of the sugar concentration, while higher concentrations of sugar in ATSBs resulted in higher numbers of mosquitoes engorging. A large increase in the LC90 of IVM was observed for females feeding on ATSBs and TSBs with 70% sucrose relative to those feeding on baits with lower sugar concentrations. No such effect was observed for males.

RNAi-mediated knockdown of arginine kinase genes leads to high mortality and negatively affect reproduction and blood-feeding behavior of Culex pipiens pallens.

Arginine kinase (AK) is one of the crucial enzymes involved in energy metabolism in invertebrates, and has been proposed as the target for RNA interference (RNAi)-based control of agricultural insect pests. While there is only one AK gene in most insects, two AK genes were identified in Culex pipiens pallens, the primary vector of lymphatic filariasis and epidemic encephalitis. The full-length cDNA sequences of CpAK1 and CpAK2 genes were obtained by reverse transcription PCR(RT-PCR) and rapid amplification of cDNA ends (RACE). The expression levels of CpAK1 and CpAK2 in different developmental stages and tissues were detected by reverse transcription quantitative PCR (RT-qPCR). The role of CpAK1 and CpAK2 in the reproduction and blood feeding behavior was analyzed using RNA interference (RNAi). Full-length cDNAs of CpAK1 and CpAK2 were isolated from Cx. pipiens pallens. Analysis of the expression pattern revealed that the mRNA level of CpAK1 was significantly higher than CpAK2 in all development stages and tissues examined, and the expressions of both CpAK1 and CpAK2 were upregulated in response to blood feeding. The co-knockdown of CpAK1 and CpAK2 mediated by RNAi led to high mortality (74.3%) of adult female mosquitoes and decreased hatchability (59.9%). Remarkably, the blood feeding rate and the engorgement rate of the female mosquitoes were negatively affected by co-injection of dsRNAs targeting CpAK1 and CpAK2. CpAK1 and CpAK2 were detected in all developmental stages and tissues, but showed divergence in expression level. RNAi-mediated knockdown of AK genes leads to high mortality and negatively affect blood-feeding behavior of Cx. pipiens pallens, suggesting that AK could be used for the target of RNAi-based mosquito control in the future.

A standardised low-cost membrane blood-feeder for Aedes aegypti made using common laboratory materials.

Blood feeding is a necessary part of laboratory studies involving mosquitoes and other hematophagous arthropods of interest in medical and ecological research. However, methods involving hosts may present serious risks, require ethics approvals and can be expensive. Here we describe an insect blood feeder made using common laboratory materials, which is low cost (<US$100) and can be constructed and operated with little technical expertise. We compared the blood feeder containing an artificial blood diet, Skitosnack, to direct human arm feeding for Aedes aegypti (Diptera: Culicidae), in terms of engorgement rate, fecundity and hatch rate. No significant difference in fecundity between the two approaches was found, (mean±SD); direct human arm: 56±26 eggs/female, artificial method: 47±25 eggs/female, P=0.569. Engorgement rates (direct human arm: 97.8±4%, artificial: 64.1±23%, P<0.05) and hatch rates (direct human arm: 75±12%, artificial: 59±14%, P<0.05) were lower in the artificially fed mosquitoes. Despite these differences, we maintained a healthy mosquito colony for 10 generations using the artificial feeding approach. Results from this comparison are within the range of other studies which compared direct host feeding with an artificial feeding method. We anticipate that the blood feeder presented here could substantially reduce costs usually required to establish a standardised and effective blood feeding method for maintaining mosquito colonies or conducting experiments, extending the capability of laboratories especially where research resources are limited, but vector-borne diseases common.

Doenitin-1: A novel Kunitz family protein with versatile functions during feeding and reproduction of the tick Haemaphysalis doenitzi.

As obligate blood-feeding ectoparasites, ticks secrete a great diversity of antithrombin molecules during feeding. In this study, a novel antithrombin gene named Doenitin-1 was characterized from the tick Haemaphysalis doenitzi. It has an open reading frame size of 426 bp; it encodes 141 amino acids and has a predicted molecular weight of 15.8 kDa. The fibrinogen coagulation test showed that the time of coagulation was increased significantly with increase in rDoenitin-1 protein concentration, and the activated partial thromboplastin time (APTT) and prothrombin time (PT) assays showed that rDoenitin-1 significantly prolonged the coagulation time of APTT, indicating that rDoenitin-1 has an anticoagulant activity in vitro. In addition, rDoenitin-1 presents a significant inhibitory activity in thrombin and cathepsin G. The hemolysis rate of rDoenitin-1 in healthy human blood cells was 4.25%, and no obvious hemolysis activity was observed. The comparison with other life stages shows that the higher expression occurs in adults, and tissue comparison indicated a higher expression in the midgut. The RNAi results indicated that interference of Doenitin-1 significantly reduced the engorgement rate and egg hatchability of H. doenitzi, and that the engorged body weight was slightly reduced. In conclusion, the results suggested that the novel gene Doenitin-1 functions in blood-feeding of H. doenitzi and performs various functions during feeding and reproduction of H. doenitzi. Doenitin-1 may be a potential vaccine candidate for tick control and for developing new antithrombotic drugs in the future.

A Study to Assess the Effectiveness of Structured Teaching Programme on Knowledge Regarding Management and Prevention of Breast Engorgement among primigravida Mothers in Selected Hospitals at Rohtas District

Breast engorgement is common among postnatal mothers especially in primigravida mothers. Breast engorgement is triggered by intensified lactogenesis causing from a reduced blood level of steroid hormone in postpartum women and with increased prolactin concentrations. The incidence rate of breast engorgement throughout the world is 1:8000 and in India 1:6500. Objectives Of The Study: To assess the knowledge of primi mother’s regarding breast engorgement through pretest.To find out the effectiveness of structured teaching programme on knowledge regarding breast engorgement problem among primi mother’s through post-test.To find out the association between post-test knowledge score with selected demographic variables. Materials And Methods : The research approach used in the present study is quantitative research approach and the research design is one group pretest and post test design is chosen for conducting the study , where there is no randomization and control group . In this design all the subjects were selected by convenience sampling technique and were given a pre-test and then post-test were conducted after they receive an intervention. The setting of the study were selected hospitals of Rohtas District. The target population comprises of all the primigravida mothers . The accessible population in this study are all the primigravida mothers in selected hospitals of rohtas district . Structured questionnaire was prepared containing a set of questions , were asked by the sample. The investigator collected the data from the 50 primigravida mothers , who came for antenatal checkup or who was admitted in ward of Sadar Hospital and NMCH. Results: Nearly 70% of the mothers are of the age group 19-25 years , 30% of the age group 26-35 years, no mother are below age of 18 years and no mothers are above 35 years.About 22% of the mother are not having any formal education, 8% of the mother’s qualification was diploma, 50% of them are graduated , 6% are postgraduated and 14% have other qualification.Approx. 92% of the primigravida mothers are housewife , 3% are teacher and 1% have other occupation.About 40% of the mothers belong to nuclear family , 50% are from joint family and 10% of mothers belong to extended family. About 92% of the primi mother are hindu and remaining 8% to muslim religion.About 2% of the primi mothers have previous information from internet , 4% have previous information from books and 94% have previous information from health professionals.The mean score of concept of breast engorgement is raised from 8.74 (SD=2.365) in pretest( Margin of error = 8.74 ±0.655 at 95% confidence interval ) to 17.58 ( SD=1.69) in post-test ( Margin of Error = 17.58 ± 0.468 at 95% confidence interval ) . The t test computed between the pre-test and post-test knowledge of primigravida mothers ( t=22.7870) was highly significant at 1% level. Conclusion: The obtained findings of the study led to the following conclusions:Majority of the primigravida mothers suffered from the breast engorgement. Deficit of knowledge regarding prevention and management of breast engorgement existed in varying degree of primigravida mothers in all the learning need area.

Low Risk Perception about Ticks and Tick-Borne Diseases in an Area Recently Invaded by Ticks in Northwestern Italy.

Risk perception, together with the adoption of measures to prevent tick bites, may strongly influence human exposure to ticks and transmitted pathogens. We created a questionnaire to evaluate how people perceive the health risk posed by ticks in an area recently invaded by these arthropods, in the western Italian Alps. Moreover, through a collaborative effort with park rangers and physicians, we investigated which tick species bite humans and their infection with pathogens (Borrelia burgdorferi s.l., Anaplasma phagocytophilum, and spotted-fever group Rickettsiae). Apart from two Dermacentor marginatus bites, we identified Ixodes ricinus (n = 124) as the main species responsible for tick bites. The investigated pathogens infected 25.4% of tested I. ricinus. The evaluation of the engorgement rate of biting I. ricinus revealed that they had been likely feeding on humans for 24 h or more, suggesting a high probability of pathogen transmission. Indeed, the questionnaires revealed that people infrequently adopt preventive measures, such as inspecting the body for ticks, although most respondents claimed that ticks are a threat to human health. Having suffered from previous tick bites was positively associated with the adoption of personal protection measures. Given the increasing incidence of tick-borne diseases in the region, the public should be better informed about the possibility of being bitten by infected ticks in order to mitigate the risk.

Engorgement of Rhipicephalus haemaphysaloides ticks blocked by silencing a protein inhibitor of apoptosis.

Inhibitors of apoptosis (IAPs) are regulators of cell death and may play a role in the salivary glands of ticks during blood-feeding. We cloned the open reading frame (ORF) sequence of the IAP gene in Rhipicephalus haemaphysaloides (RhIAP). The RhIAP ORF of 1887bp encodes a predicted protein of 607 amino acids, which contains three baculovirus IAP repeat domains and a RING finger motif. A real-time PCR assay showed that RhIAP mRNA was expressed in all the tick developmental stages (eggs, larvae, nymphs, and adults) and in all tissues examined (midgut, ovary, salivary glands, fat body, and hemolymph). Western blot showed that the protein level of RhIAP in salivary glands increased during tick blood-feeding and decreased towards the end of tick engorgement. RhIAP gene silencing in vitro experiments with salivary glands demonstrated that RhIAP could be effectively knocked down within 48h after dsRNA treatment, and as a consequence, salivary glands displayed apoptotic morphology. RhIAP gene silencing also inhibited tick blood-feeding and decreased the engorgement rate. These data suggest that RhIAP might be a suitable RNAi target for tick control.

Expression and function assessment of two serpin-type serine protease inhibitors from Haemaphysalis doenitzi

Serine protease inhibitors (serpins) in ticks are implicated in the modulation of the vertebrate host response to the tick bite. Experimentally, it has been demonstrated that serpins interfere with tick-borne pathogen transmission. However, knowledge on serpins in the tick Haemaphysalis doenitzi is lacking. In this study, the expression of two serpin genes, named HDS1 and HDS2, were assessed in H. doenitzi, and their roles in immune regulation were further investigated. The expression of HDS1 and HDS2 showed no tissue specificity, with maximum expression levels detected in the hemolymph and salivary gland, respectively. Among the developmental stages, the highest expression of HDS1 and HDS2 were detected in larvae and adults, respectively. The recombinant protein rHDS1 displayed obvious inhibitory effects on trypsin and thrombin, whereas rHDS2 clearly inhibited thrombin only. In addition, rHDS1 and rHDS2 showed certain inhibitory activities against bacteria and fungi. The female engorgement body weight, female engorgement rate, and egg hatchability were significantly decreased after injection of double-stranded RNA (dsRNA) of HDS1 gene, whereas no significant effects were observed concerning the feeding period or attachment rate at 24 h after introduction via rabbit ears. When injected with dsRNA of HDS2 gene, no significant effect was observed on the attachment rate at 24 h after introduction into the rabbit ears, but the engorgement body weight and engorgement rate of female ticks were significantly decreased, and no egg hatchment occurred. The above results contribute to better understanding the function of serpins in the development and innate immunity of H. doenitzi.

Uptake and fecal excretion of Coxiella burnetii by Ixodes ricinus and Dermacentor marginatus ticks

BackgroundThe bacterium Coxiella burnetii is the etiological agent of Q fever and is mainly transmitted via inhalation of infectious aerosols. DNA of C. burnetii is frequently detected in ticks, but the role of ticks as vectors in the epidemiology of this agent is still controversial. In this study, Ixodes ricinus and Dermacentor marginatus adults as well as I. ricinus nymphs were fed on blood spiked with C. burnetii in order to study the fate of the bacterium within putative tick vectors.MethodsBlood-feeding experiments were performed in vitro in silicone-membrane based feeding units. The uptake, fecal excretion and transstadial transmission of C. burnetii was examined by quantitative real-time PCR as well as cultivation of feces and crushed tick filtrates in L-929 mouse fibroblast cells and cell-free culture medium.ResultsTicks successfully fed in the feeding system with engorgement rates ranging from 29% (D. marginatus) to 64% (I. ricinus adults). Coxiella burnetii DNA was detected in the feces of both tick species during and after feeding on blood containing 105 or 106 genomic equivalents per ml blood (GE/ml), but not when fed on blood containing only 104 GE/ml. Isolation and cultivation demonstrated the infectivity of C. burnetii in shed feces. In 25% of the I. ricinus nymphs feeding on inoculated blood, a transstadial transmission to the adult stage was detected. Females that molted from nymphs fed on inoculated blood excreted C. burnetii of up to 106 genomic equivalents per mg of feces.ConclusionsThese findings show that transstadial transmission of C. burnetii occurs in I. ricinus and confirm that I. ricinus is a potential vector for Q fever. Transmission from both tick species might occur by inhalation of feces containing high amounts of viable C. burnetii rather than via tick bites.

Caracterization of glutathione S-transferase of Dermacantor marginatus and effect of the recombinant antigen as a potential anti-tick vaccine

Dermacentor marginatus is one of the main tick species in northwestern China, and is a vector of various tick-borne pathogens. Tick control method largely depends on chemical agents, but the disadvantages of using such approach would cause environmental damage and the risk of developing tick resistance to acaricides. Vaccination of tick protective antigen is an eco-friendly approach which is an alternative and promising method to mitigate tick infestation in livestock. In the study, a mu-class glutathione S-transferase (GST) sequence of D. marginatus was cloned and the recombinant protein (rDmGST) was expressed. Transcriptional level of the GST was measured together with native GST activity of the tick. Finally, A vaccine trial on rabbits against D. marginatus was proceeded to evaluate the anti-tick effect of rDmGST. Results reveled that the CDs of the D. margiantus glutathione S-transferase mu 1 gene has 669 base pair nucleotide sequence encoding a 223 amino acid. The deduced GST protein sequence had over 95 % similarity with that of D. variabilis. The rDmGST was efficiently expressed soluble and purified by His trap affinity chromatography. Enzyme activity of native GST and transcriptional profiles of the GST showed up-regulation in different stages and organs of D. marginaus during blood feeding. Polyclonal antibody reacted with rDmGST in Western blotting. Tick challenge on rDmGST inoculated rabbits showed reductions in adult female engorgement rate, total egg mass and egg hatching rate with an overall vaccine efficacy of 43.69 %. The results of the experiment indicated the GST has potential value to be an effective protective antigen of D. marginatus.