A simplified molecular tool for detecting the Chagas etiological agent using a vector feces sample in field conditions.

Triatomine bugs are vectors of Trypanosoma cruzi, the etiologic agent of Chagas disease in the American continent. Here, we have tested a loop-mediated isothermal amplification (LAMP) test for a direct detection of T. cruzi in feces of Triatoma infestans, the main vector of this parasite in the Southern Cone of America. The analytical evaluation showed positive results with samples of triatomine feces artificially inoculated with DNA from strains of T. cruzi corresponding to each Discrete Typing Units (I-VI), with a sensitivity of up to one parasite per reaction. Conversely, the reaction yielded negative results when tested with DNA from Trypanosoma rangeli and other phylogenetically related and unrelated organisms. In triatomines captured under real field conditions (from urban households), and defined as positive or negative for T. cruzi using the reference microscopy technique, the LAMP test achieved a concordance of 100 %. Our results demonstrate that this LAMP reaction exhibits excellent analytical specificity and sensitivity without interference from the fecal matrix, since all the reactions were conducted without purification steps. This simple molecular diagnostic technique can be easily used by vector control agencies under field conditions.

Genetic polymorphisms of inflammatory and bone metabolism related proteins in a population with dental implants of the Basque Country. A case-control study.

BACKGROUND: Peri-implantitis (PI) is a frequent inflammatory disorder characterised by progressive loss of the supporting bone. Not all patients with recognised risk factors develop PI. The aim of this study is to evaluate the presence of single nucleotide polymorphisms (SNP) of inflammatory and bone metabolism related proteins in a population treated with dental implants from the Basque Country (Spain). METHODS: We included 80 patients with diagnosis of PI and 81 patients without PI, 91 women and 70 men, with a mean age of 60.90 years. SNPs of BMP-4, BRINP3, CD14, FGF-3, FGF-10, GBP-1, IL-1α, IL-1ß, IL-10, LTF, OPG and RANKL proteins were selected. We performed a univariate and bivariate analysis using IBM SPSS® v.28 statistical software. RESULTS: Presence of SNPs GBP1 rs7911 (p = 0.041) and BRINP3 rs1935881 (p = 0.012) was significantly more common in patients with PI. Patients with PI who smoked (> 10 cig/day) showed a higher presence of OPG rs2073617 SNP (p = 0.034). Also, BMP-4 rs17563 (p = 0.018) and FGF-3 rs1893047 (p = 0.014) SNPs were more frequent in patients with PI and Type II diabetes mellitus. CONCLUSIONS: Our findings suggest that PI could be favoured by an alteration in the osseointegration of dental implants, based on an abnormal immunological response to peri-implant infection in patients from the Basque Country (Spain).

Clinical analysis of the tooth-implant papilla for two narrow-diameter titanium-zirconium implants in the anterior area: prospective controlled clinical study.

BACKGROUND: Rehabilitation of the anterior area when the mesio-distal space is reduced is a challenge for the clinician, due to the patient's anatomical limitations and aesthetic requirements. Narrow Diameter Implants (NDI) are an option of treatment when the standard diameter implant is not possible, but the evidence is scarce. This prospective clinical study aims to analyze the formation of the tooth-implant papilla between the implant and the adjacent natural tooth in the maxillary lateral incisors and mandibular incisors. METHODS: A total of 40 patients treated with NDI, of titanium-zirconium (Ti-Zr) alloy i.e., 2.9 mm Test Group (TG) and 3.3 mm Control Group (CG), were included. The mesiodistal distance between the adjacent natural teeth was used for implant selection, maintaining 1.5 mm between the fixation and the adjacent tooth. Clinical assessment was performed by a clinical examiner at 6 and 12 months after the final prosthesis. The primary variable was the Jemt Papillary Index. Also, implant survival rate (SR), complications, Implant Stability Quotient (ISQ), and patient-reported outcomes measures (PROMs) such as aesthetics, chewing, phonation, comfort, and self-esteem were analyzed. RESULTS: A significant amount of papilla filling was observed concerning the baseline, with a trend towards more formation of the papilla in the TG, with a JPI score of 3. No significant differences were observed between the two groups regarding implant SR, clinical parameters, and complications. In terms of PROMs, a higher satisfaction in the TG was observed, with significant intergroup differences for aesthetics, comfort, self-esteem, and primary stability ISQ (TG: 59.05 (SD: 5.4) vs. CG: 51.55 (SD: 5.7)). CONCLUSIONS: The 2.9 mm diameter Ti-Zr implants achieved a formation of papilla similar to 3.3 mm implants in the anterior region at 12 months of follow-up after the final prosthetic restoration. The use of Ti-Zr implants with a diameter of 2.9 mm to rehabilitate single teeth in areas of the anterior region, where the mesiodistal distance is limited, showed favorable clinical results and a high degree of satisfaction during 1 year of observation similar to 3.3 mm dental implants. TRIAL REGISTRATION: This study was retrospectively registered in ClinicalTrials.gov with the number NCT05642520, dated 18/11/2022.

Comparative study of the modified VISTA technique (m-VISTA) versus the coronally advanced flap (CAF) in the treatment of multiple Miller class III/RT2 recessions: a randomized clinical trial.

OBJECTIVES: To compare the percentage of mean root coverage (MRC%) obtained in the treatment of multiple Miller class III/RT2 gingival recessions using the modified VISTA (m-VISTA) technique versus the coronally advanced flap (CAF) technique, using a connective tissue graft (CTG) in both cases. MATERIALS AND METHODS: Twenty-four patients were randomly treated with m-VISTA (test group (TG) = 12) or CAF (control group (CG) = 12). A calibrated, experienced, and blinded examiner collected data related to multiple periodontal clinical variables, especially the recession (REC) in order to calculate the MRC% at 6 and 12 months, which was the primary outcome of the study. Also, the radiological bone level, the characteristics of the CTG, and postsurgical incidences were assessed. Finally, a descriptive and an analytical statistical analysis of the variables and their associations was performed. RESULTS: The recessions (n = 84) were located mainly in the mandible (n = 65) and in posterior sectors (premolars: n = 35; molars: n = 8). At 6 months, the MRC% was 61% (2 mm) for both study groups, and at 12 months, it increased to 73.26% (2.11 mm) in the TG and decreased to 56.49% (1.78 mm) in the CG. CONCLUSION: When approaching multiple Miller class III/RT2 recessions, there were no statistically significant differences in the MRC% at 6 and 12 months between the group treated with the m-VISTA technique and the group treated with the CAF. CLINICAL RELEVANCE: The characteristics of the m-VISTA technique, such as the closed approach, the mobilization of the papilla, and the coronal stabilization of the CTG, could facilitate the maturation of the tissues in the treatment of Miller class III/RT2 recessions. This would favor better root coverage. TRIAL REGISTRATION: NCT03258996.

The influence of larval density on triacylglycerol content in Aedes aegypti (Linnaeus) (Diptera: Culicidae).

Given the importance of Aedes aegypti as an arbovirus vector, understanding the impact of population density during larval development is fundamental to improve control methods. The aims of this study were to analyze the effects of larval density on the triacylglycerol (TAG) reserves, fecundity, and the size of mosquitos. To evaluate the influence of density on the amount of TAG in the different stages of development of A. aegypti, the larvae were reared in densities of 0.04, 0.32, and 0.8 larvae/ml, represented by D1, D2, and D3, respectively. Larval rearing density affected the amount of TAG in the different developmental stages of this insect. The group reared with the highest population density (D3) presented greater storage of TAG, except when analyzing the amount of TAG µg/protein in the fat body of blood-fed females. In addition, it was possible to observe higher resistance to fasting and a greater number of eggs laid. Insects reared in D2 and D3 were larger than those in the D1 group. This study provides interesting data for future investigations on how the density of larval rearing affects the lipid metabolism for synthesis and mobilization of TAG stored in A. aegypti and how it influences size and reproduction.

Urban infestation by Triatoma infestans (Hemiptera: Reduviidae), an overlooked phenomena for Chagas disease in Argentina.

Vector-borne transmission of Chagas disease in urban areas of Argentina has been an overlooked phenomena. We conducted the first comprehensive cross-sectional study of domestic infestation with Triatoma infestans and vector infection with Trypanosoma cruzi in a metropolitan area of San Juan, Argentina. Our results document the occurrence of T. infestans infected with T. cruzi in human sleeping quarters. In this urban setting, we also show that infestation was associated with construction materials, the presence of chickens, cats and a large number of dogs that can provide blood meals for the vector. Our findings reveal new challenges for vectorial control agencies.

Description of the modified vestibular incision subperiosteal tunnel access (m-VISTA) technique in the treatment of multiple Miller class III gingival recessions: a case series.

BACKGROUND: Gingival recession is a common finding in the adult population. It is considered a challenge for clinicians to obtain a complete root coverage of Miller class III recession. The aim of this case series was to assess the outcomes achieved with the use of modified VISTA technique (m-VISTA) in patients having multiple Miller class III recessions after 6 months. METHODS: Ten patients (six women and four men; mean age: 53 years), who showed multiple Miller class III recessions (depth ≥ 2 mm) and who met the established inclusion and exclusion criteria, were treated by postgraduate students with the use of m-VISTA technique. RESULTS: A total of 38 recessions were performed. The recessions were mainly located in the mandible (80%), which included six molars. The mean baseline recession was 3.12 mm. Post the intervention, a mean root coverage of 58.72% was achieved, with complete root coverage observed in 29% of the recessions. CONCLUSIONS: m-VISTA may offer several advantages in the treatment of Miller class III gingival recession. Nevertheless, more clinical trials with a longer follow-up period are needed to arrive at a concrete conclusion about its advantages. TRIAL REGISTRATION: NCT03258996. Data registration: 08/18/2017.

Complete root coverage in the treatment of Miller class III or RT2 gingival recessions: a systematic review and meta-analysis.

BACKGROUND: The primary objective of this systematic review and meta-analysis was to assess the evidence on complete root coverage (CRC) achieved by periodontal plastic techniques in the treatment of Miller class III/RT2 gingival recessions, comparing techniques developed along the twentieth century (pre-twenty-first) versus surgical approaches of the twenty-first century (21st). METHODS: An electronic bibliographic search was carried out in four databases up to December 2019, focusing on studies that reported CRC results in Miller class III or RT2 recessions treatment with at least a six-month follow-up. In addition, a random-effects models' meta-analysis was performed for the CRC, comparing pre-twenty-first versus twenty-first century techniques at 6 months, 12 months and more than 12 months. RESULTS: Thirty-seven publications were included. A total of 933 gingival recessions were treated, 298 with pre-twenty-first century surgical techniques and 635 with techniques from the twenty-first century. CRC was achieved at 6 months on half of the recessions (pre-twenty-first: 57.60% vs. 21st: 51.11%), but decreased markedly for twenty-first century techniques at 12 months (pre-twenty-first: 63.82% vs. 21st: 32.87%). Thereafter, this difference was the other way around (> 12 months: pre-twenty-first: 5.26% vs. 21st: 19.65%). The meta-analysis showed a high heterogeneity, with no significant differences amongst the techniques. CONCLUSIONS: Although CRC might be achievable by treating Miller class III or RT2 recessions with any of the described techniques, its long-term stability is not predictable. More randomized clinical trials with longer follow-ups and several visits, are needed. In addition, the patient's satisfaction should also be assessed.

Role of Porphyromonas gingivalis in oral squamous cell carcinoma development: A systematic review.

OBJECTIVE: The target of the current systematic review is to gather and synthesize the most recent scientific information about the role of Porphyromonas gingivalis in the molecular pathways of oral squamous cell carcinoma (OSCC). BACKGROUND: Oral squamous cell carcinoma is the most common malignancy of the oral cavity, with a poor prognosis and a low survival rate. Etiology is multifactorial but consumption of tobacco and alcohol is the most important risk factors. P gingivalis is a Gram-negative anaerobic bacterium commonly found in oral microbiota that has been linked to periodontal disease (PD), and recently to OSCC. However, its association with OSCC development is not well defined. MATERIAL AND METHODS: A bibliographic research was carried out selecting articles published until 2019, on PubMed, Web of Science, and Scopus databases, with the keywords "Porphyromonas gingivalis," "oral cancer," "oral squamous cell carcinoma," and "periodontal pathogen." RESULTS: Seventeen articles, 14 in vitro and three in animal models, were selected. Models mimicking OSCC were OSCC pre-established cell lines (11 studies), OSCC/ healthy human biopsies (three studies), and animals with OSCC (three studies). P gingivalis strains used to cause infection in these studies were ATCC 33277, 381, and W83. CONCLUSIONS: Porphyromonas gingivalis could play an important role in OSCC development and could be involved in three different stages: epithelial-mesenchymal transition of malignant cells, neoplastic proliferation, and tumor invasion. Current findings emphasize the convenience of treatment and control approaches of PD as part of the primary prevention of OSCC.

Evaluation and characterization of multimorbidity profiles, resource consumption and healthcare needs in extremely elderly people.

OBJECTIVES: Spanish population lifespan is one of the longest in the world. Moreover, it is known that elderly people have less chronic illnesses associated with aging. Our aims were to determine how Clinical Risk Group (CRG) predicts future use of healthcare resources in extremely elderly people without diabetes (T2DM) and to explore CRG correlation with health conditions. DESIGN: Prospective cross-sectional study. SETTING: Rio Hortega University Hospital. PARTICIPANTS: Hospitalized patients >80 years old without T2DM, during 2017. MAIN OUTCOME MEASURES: Mental status was evaluated using Pfeiffer test (SPMQS), Basic Activities of Daily Living (BADLs) and Instrumental Activities of Daily Living (IADLs) were estimated using the Older Americans Resources and Services questionnaire. Comorbidity was evaluated using Charlson index (CI) and health-related quality of life (HRQoL) with EuroQoL (EQ5D3L). CRG classification system was obtained from electronic clinical records. Data were analyzed using SPSS v.15.0. RESULTS: In total, 305 patients were identified (59% women), mean age 88 ± 5 and 38% were aged >90. Estimated HRQoL was 0.43 ± 0.33 for EQ5D3L-index-value. Mean dependence level was 6.2 ± 5 for BADLs and 9.2 ± 5 for IADLs. In total, 31.6% of patients had severe cognitive impairment with a mean score of 5.4 ± 3.6 in SPMQS. In total, 30.2% of patients were categorized as G3, and presented high comorbidity more frequently than the rest. Corrected CI mean score was 6.2 ± 1.7. Significant relationship was founded in survival time, number of admissions and CI score. CONCLUSIONS: Using predictive risk models like CRG is supposed to assess the complexity of morbidity but in our extremely elderly population partially fail in stratify and predict health resource consumption.

Do 'difficult to identify' pulmonary vein connections explain continuing high recurrence rates after atrial fibrillation ablation?

Despite the emerging technical evolution of the last two decades, the primary success rate of single-procedure pulmonary vein isolation (PVI), the cornerstone for any atrial fibrillation ablation procedure, is highly variable ranging from 53% to 92%. The recent development of ultra-high-density electroanatomic mapping systems, capable of acquiring and annotating multiple electrograms, with high spatiotemporal precision, which are processed by automated algorithms to generate activation and substrate maps to support and guide ablation procedures, has opened a new stage in cardiac electrophysiology. In this article, we review the existing evidence on the utility of high-density mapping on catheter-based PVI, the possibility to detect pulmonary vein potentials that remain undetected when using a standard approach and its potential relevance to the clinical outcome, and how this new technology is providing novel pathophysiological insights on complete PVI and atrial fibrillation ablation outcomes.

One-year results of a nonsurgical treatment protocol for peri-implantitis. A retrospective case series.

OBJECTIVES: The aim of this study was to assess the clinical outcomes of a nonsurgical treatment protocol for peri-implantitis and to evaluate the influence that some factors could have on the results of this treatment. MATERIAL AND METHODS: In this retrospective case series, patients with at least one implant with peri-implantitis, treated with a nonsurgical protocol and with a one-year follow-up, were included. Clinical parameters (probing depth, recession, bleeding, and/or suppuration on probing) were collected at baseline, 6 weeks, 3, 6, and 12 months. Radiographic bone levels were assessed in periapical radiographs taken at baseline and 12 months. An analysis of the factors significantly associated with marginal bone level changes was performed. Descriptive and analytic statistics were carried out at the patient and at the implant level, as well as a multiple linear regression analysis. RESULTS: Data from 37 patients with 70 implants were analyzed. There was a general and consistent improvement from baseline compared to all follow-up points in the clinical variables. A significant radiographic bone gain of 0.91 mm was observed. The factors significantly associated were baseline plaque index, sex, and age at patient level, and type of prosthesis and implant location at implant level. CONCLUSIONS: Within the limitations of this study, this nonsurgical treatment protocol might be considered as a first treatment option for peri-implantitis. More studies are needed, with larger sample sizes and longer follow-ups, to confirm these outcomes and their long-term stability.

The eco-epidemiology of Triatoma infestans in the temperate Monte Desert ecoregion of mid-western Argentina.

BACKGROUND: The eco-epidemiological status of Chagas disease in the Monte Desert ecoregion of western Argentina is largely unknown. We investigated the environmental and socio-demographic determinants of house infestation with Triatoma infestans, bug abundance, vector infection with Trypanosoma cruzi and host-feeding sources in a well-defined rural area of Lavalle Department in the Mendoza province. METHODS: Technical personnel inspected 198 houses for evidence of infestation with T. infestans, and the 76 houses included in the current study were re-inspected. In parallel with the vector survey, an environmental and socio-demographic survey was also conducted. Univariate risk factor analysis for domiciliary infestation was carried out using Firth penalised logistic regression. We fitted generalised linear models for house infestation and bug abundance. Blood meals were tested with a direct ELISA assay, and T. cruzi infection was determined using a hot-start polymerase chain reaction (PCR) targeting the kinetoplast minicircle (kDNA-PCR). FINDINGS: The households studied included an aged population living in precarious houses whose main economic activities included goat husbandry. T. infestans was found in 21.2% of 198 houses and in 55.3% of the 76 re-inspected houses. Peridomestic habitats exhibited higher infestation rates and bug abundances than did domiciles, and goat corrals showed high levels of infestation. The main host-feeding sources were goats. Vector infection was present in 10.2% of domiciles and 3.2% of peridomiciles. Generalised linear models showed that peridomestic infestation was positively and significantly associated with the presence of mud walls and the abundance of chickens and goats, and bug abundance increased with the number of all hosts except rabbits. MAIN CONCLUSIONS: We highlight the relative importance of specific peridomestic structures (i.e., goat corrals and chicken coops) associated with construction materials and host abundance as sources of persistent bug infestation driving domestic colonisation. Environmental management strategies framed in a community-based programme combined with improved insecticide spraying and sustained vector surveillance are needed to effectively suppress local T. infestans populations.

Phenotypic Plasticity In Response To Seasonal Variation In Populations of Culex (Melanoconion) Bastagarius.

The present study aimed to determine the effects of seasonal variation on phenotypic variation in Culex bastagarius, using geometric morphometric analysis based on wing shape and size. Samples were collected in the Guapiaçu Ecological Reserve, in Rio de Janeiro, Brazil. Mosquitoes were captured once every 2 months (December 2012-January 2014) using light traps. The results of geometric morphometric analysis revealed variations in wing size; however, variability was not evident in wing shape. The present study provides novel data regarding phenotypic plasticity of Cx. bastagarius that have been scarcely addressed in the past.

Long-Term Trends in Mosquito Vector Populations and Their Impact on Yellow Fever Outbreaks in Atlantic Forest Fragments of Rio De Janeiro, Brazil (2016-2021).

Among all living beings, mosquitoes account for the highest number of human fatalities. Our study aimed to determine mosquito egg abundance fluctuation from 2015 to 2020, in order to observe which years had the highest mosquito vector densities and whether they coincided with yellow fever virus outbreaks in both human and nonhuman primates. The study area included Atlantic Forest fragments in the state of Rio de Janeiro. Studies from the Diptera Laboratory at FIOCRUZ were selected and compared along a timeline period of the field collections. The highest peak in egg abundance from the analyzed studies was observed from 2016 to 2017 and from 2015 to 2016. The lowest egg abundance was during the collection periods from 2018 to 2019 and 2019 to 2020. The species with the highest abundance throughout all the periods of the studies analyzed was Haemagogus leucocelaenus, representing 87% of all epidemiological species identified. The species with the lowest abundance was Hg. Janthinomys, representing only 1%. Monitoring the population of mosquitoes is imperative for disease surveillance, as the rise in specimens of various vector species directly impacts the occurrence of yellow fever cases in both nonhuman primates and human populations.

Applicability of Traps for Collecting Mosquito Immatures (Diptera: Culicidae) for Entomological Surveillance of Arbovirus Vectors in a Remnant of the Atlantic Forest, Rio de Janeiro State, Brazil.

Diverse larval habitats significantly influence female mosquito oviposition. Utilizing traps that simulate these habitats is helpful in the study of the bioecology and characteristics of pathogen-transmitting species during oviposition. This study evaluated the feasibility of different traps in natural environments by comparing sampling methods and detecting the oviposition of epidemiologically important mosquitoes, with emphasis on Haemagogus species, in a fragment of the Atlantic Forest in Silva Jardim, Rio de Janeiro State, Brazil. Monthly collections were conducted from March 2021 to October 2023 using four types of traps: plastic containers, tires, bamboo, and sapucaia. Immatures were collected from these traps using a pipette, placed in plastic bags, and transported to the laboratory. Tire was the most efficient trap, showing the highest mosquito abundance (n = 1239) and number of species (S = 11). Conversely, the plastic container trap exhibited the lowest diversity (H = 0.43), with only two species and a low mosquito abundance (n = 26). The bamboo trap captured six species and recorded the second-highest diversity index (H = 1.04), while the sapucaia trap captured five species and had the third-highest diversity index (H = 0.91). Of the total immatures collected, 1817 reached adulthood, comprising 13 species, two of which are vectors of the sylvatic yellow fever virus: Haemagogus leucocelaenus and Haemagogus janthinomys. In conclusion, detecting key vectors of the sylvatic yellow fever virus in Brazil highlights the need for ongoing entomological and epidemiological surveillance in the study area and its vicinity. These efforts are crucial for monitoring vector presence and activity, identifying potential transmission hotspots, and devising effective control and prevention strategies.

Endoperiodontal lesions: diagnosis first, then treatment and not always tooth extraction: a cross-sectional survey in Spain and a proposal of a clinical treatment protocol.

Background: Endoperiodontal lesion (EPL) is defined as a pathological communication between pulpal and periodontal tissues. Currently, accurate diagnosis and treatment of this pathology are challenging. This study aims to identify the different endoperiodontal therapies to propose a clinical protocol to simplify and unify the criteria for EPL treatment. Material and Methods: Observational cross-sectional study through an electronic survey. This study matches STROBE guidelines. The anonymous questionnaire contained open-ended and close-ended questions and was distributed to dentistry professors of the UPV/EHU and different professionals from Spanish associations and scientific societies. The data collected were analyzed using descriptive and analytical statistics. Results: A total of 128 responses were obtained, of which 120 were active professionals or had not been so for less than 5 years. The majority of professionals were women (65.6%) and from the Basque Country (63.9%). A total of 86.6% reported having complementary studies to a degree or a bachelor's degree. The treatments performed by these professionals were similar to those reported in the literature, which started with root canal treatment when there was an endodontic origin (91.5%), and with basic periodontal treatment when periodontal (51.3%). Conclusions: Considering the current scientific evidence and the clinical practice of professionals in the treatment of EPL, we designed a clinical protocol. This protocol needs validation in larger populations and with longer follow-ups. Key words:Clinical protocol, Dental pulp diseases, Periodontal diseases, Review, Surveys and questionnaires.

Variety is the spice: The role of morphological variation of Triatoma infestans (Hemiptera, Reduviidae) at a macro-scale.

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi (Chagas, 1909). One of the primary vectors of T. cruzi in South America is Triatoma infestans (Klug, 1834). This triatomine species is distributed across a huge latitudinal gradient, inhabiting domiciliary , peridomiciliary , and wild environments. Its wide geographic distribution provides an excellent opportunity to study the relationships between environmental gradients and intraspecific morphological variation. In this study, we investigated variations in wing size and shape in T. infestans across six ecoregions. We aimed to address the following questions: How do wing size and shape vary on a regional scale, does morphological variation follow specific patterns along an environmental or latitudinal gradient, and what environmental factors might contribute to wing variation? Geometric morphometric methods were applied to the wings of 162 females belonging to 21 T. infestans populations, 13 from Argentina (n = 105), 5 from Bolivia (n = 42), and 3 from Paraguay (n = 15). A comparison of wing centroid size across the 21 populations showed significant differences. Canonical Variate Analysis (CVA) revealed significant differences in wing shape between the populations from Argentina, Bolivia, and Paraguay, although there was a considerable overlap, especially among the Argentinian populations. Well-structured populations were observed for the Bolivian and Paraguayan groups. Two analyses were performed to assess the association between wing size and shape, geographic and climatic variables: multiple linear regression analysis (MRA) for size and Partial Least Squares (PLS) regression for shape. The MRA showed a significant general model fit. Six temperature-related variables, one precipitation-related variable, and the latitude showed significant associations with wing size. The PLS analysis revealed a significant correlation between wing shape with latitude, longitude, temperature-related, and rainfall-related variables. Wing size and shape in T. infestans populations varied across geographic distribution. Our findings demonstrate that geographic and climatic variables significantly influence T. infestans wing morphology.

Relationship between genetic diversity and morpho-functional characteristics of flight-related traits in Triatoma garciabesi (Hemiptera: Reduviidae).

BACKGROUND: Triatoma garciabesi, a potential vector of the parasitic protozoan Trypanosoma cruzi, which is the causative agent of Chagas disease, is common in peridomestic and wild environments and found throughout northwestern and central Argentina, western Paraguay and the Bolivian Chaco. Genetic differentiation of a species across its range can help to understand dispersal patterns and connectivity between habitats. Dispersal by flight is considered to be the main active dispersal strategy used by triatomines. In particular, the morphological structure of the hemelytra is associated with their function. The aim of this study was to understand how genetic diversity is structured, how morphological variation of dispersal-related traits varies with genetic diversity and how the morphological characteristics of dispersal-related traits may explain the current distribution of genetic lineages in this species. METHODS: Males from 24 populations of T. garciabesi across its distribution range were examined. The cytochrome c oxidase I gene (coI) was used for genetic diversity analyses. A geometric morphometric method based on landmarks was used for morpho-functional analysis of the hemelytra. Centroid size (CS) and shape of the forewing, and contour of both parts of the forewing, the head and the pronotum were characterised. Length and area of the forewing were measured to estimate the aspect ratio. RESULTS: The morphometric and phylogenetic analysis identified two distinct lineages, namely the Eastern and Western lineages, which coincide with different ecological regions. The Eastern lineage is found exclusively in the eastern region of Argentina (Chaco and Formosa provinces), whereas the Western lineage is prevalent in the rest of the geographical range of the species. CS, shape and aspect ratio of the hemelytra differed between lineages. The stiff portion of the forewing was more developed in the Eastern lineage. The shape of both portions of the hemelytra were significantly different between lineages, and the shape of the head and pronotum differed between lineages. CONCLUSIONS: The results provide preliminary insights into the evolution and diversification of T. garciabesi. Variation in the forewing, pronotum and head is congruent with genetic divergence. Consistent with genetic divergence, morphometry variation was clustered according to lineages, with congruent variation in the size and shape of the forewing, pronotum and head.