Allergy: Evaluation of 16 years (2007-2022) results of the shared external quality assessment program in Belgium, Finland, Portugal and The Netherlands.

OBJECTIVES: This paper evaluates 16 year results of the Allergy EQA program shared by EQA organisers in Belgium, Finland, Portugal, and The Netherlands. METHODS: The performance of Thermo Fisher and Siemens user groups (in terms of concordance between both groups, between laboratory CV, prevalence of clinically significant errors) and suitability of samples (stability and validity of dilution of patient samples) are evaluated using data of 192 samples in the EQA programs from 2007 to 2022. Measurands covered are total IgE, screens and mixes, specific IgE extracts and allergen components. RESULTS: There is perfect (53 %), acceptable (40 %) and poor (6 %) concordance between both method groups. In case of poor concordance the best fit with clinical data is seen for Thermo Fisher (56 %) and Siemens (26 %) respectively. The between laboratory CV evolves from 7.8 to 6.6 % (Thermo Fisher) and 7.3 to 7.7 % (Siemens). The prevalence of blunders by individual laboratories is stable for Siemens (0.4 %) and drops from 0.4 to 0.2 % for Thermo Fisher users. For IgE, the between year CV of the mean of both user groups is 1 %, and a fifteen-fold dilution of a patient sample has an impact of 2 and 4 % on the recovery of Thermo Fisher and Siemens user groups. CONCLUSIONS: The analytical performance of Thermo Fisher is slightly better than that of Siemens users but the clinical impact of this difference is limited. Stability of the sample and the low impact of dilution on the recovery of measurands demonstrates the suitability for purpose of the EQA program.

Response of aquatic insects to an environmental gradient in Amazonian streams.

The increasing land use in the Amazon region has resulted in the widespread substitution of forest areas with pasture and bauxite mining. These land uses reduce the forest cover of streams and modify their characteristics, reducing the diversity of aquatic insect assemblages. In the present study, we aimed to identify the threshold of the assemblages of the larvae of insects of the orders Ephemeroptera, Plecoptera, and Trichoptera (collectively known as EPT), and adults of the order Odonata, along an environmental gradient of land use and land cover (LULC). We sampled 30 streams along an environmental gradient determined by the proportion of forest, pasture, and bauxite mining observed within the catchment of each stream. We identified 12 taxa associated with forest (nine positively and three negatively) and four negatively associated with pasture. However, no taxa were associated explicitly with the bauxite mining gradient. As forest is converted to pasture, the abundance and frequency of occurrence of the taxa sensitive to pasture are reduced, reflecting their environmental sensitivity and their potential as sentinels of preserved streams. The identification of the thresholds of the EPT and odonates taxa allowed us to determine which of these organisms are positively or negatively associated with the environmental gradient of LULC in Amazonian streams. We hope that the results of the present study can be applied in future biomonitoring programs, particularly for monitoring the response of aquatic insects to the degradation of streams.

Aquatic insects and their environmental predictors: a scientometric study focused on environmental monitoring in lotic environmental.

Since early studies about aquatic ecology, it has been found that changes in environmental conditions alter aquatic insect communities. Based on this, the combined study of environmental conditions and aquatic insect communities has become an important tool to monitor and manage freshwater systems. However, there is no consensus about which environmental predictors and facets of diversity are more useful for environmental monitoring. The objective of this work was to conduct a scientometric analysis to identify the main environmental predictors and biological groups used to monitor and manage lotic freshwater systems. We conducted a scientometric study on the Web of Science platform using the following words: stream, river, aquatic insect, Ephemeroptera, Plecoptera, Trichoptera, Odonata, Heteroptera, Chironomidae, bioindicator, environmental change, anthropic, and land use. Although most of the environmental predictors employed are local, intrinsic of freshwater systems using local environmental and associated landscape variables is a better strategy to predict aquatic insect communities. The facets of diversity most used are composition and richness of species and genera, which are not efficient at measuring the loss of ecosystem services and extinction of phylogenetic lineages. Although very important, these functional and phylogenetic facets are poorly explored for this purpose. Even though tropical regions are the most diverse globally and are experiencing major losses of native vegetation, these ecosystems are the least studied, a knowledge gap that needs addressing to better understand the effect of anthropogenic activities on the diversity of aquatic insects.

Pro-inflammatory Cytokines and Resistant Hypertension: Potential for Novel Treatments?

PURPOSE OF REVIEW: To gather data from studies evaluating the pro-inflammatory profile of individuals with resistant hypertension (RH), and bring a clinical update of new and potential complementary therapies to treat inflammation in RH. RECENT FINDINGS: Increases in pro-inflammatory cytokines are related to elevated blood pressure and target organ damage in RH patients. Clinical and experimental studies have shown that some biological therapies, especially TNF-α inhibitors, regulated pro- and anti-inflammatory cytokines associated with improvements in clinical outcomes, although they are not yet reported in RH. New emerging therapies to treat inflammation in RH, although promising, are still hypotheses that have not been scientifically confirmed in clinical trials. For this reason, inflammation-target treatments, such as the TNF-α and IL-6 inhibitors, should be encouraged for testing as complementary therapies in RH in order to elucidate their potential benefits.

Analytical performance of 17 general chemistry analytes across countries and across manufacturers in the INPUtS project of EQA organizers in Italy, the Netherlands, Portugal, United Kingdom and Spain.

BACKGROUND: Optimum patient care in relation to laboratory medicine is achieved when results of laboratory tests are equivalent, irrespective of the analytical platform used or the country where the laboratory is located. Standardization and harmonization minimize differences and the success of efforts to achieve this can be monitored with international category 1 external quality assessment (EQA) programs. METHODS: An EQA project with commutable samples, targeted with reference measurement procedures (RMPs) was organized by EQA institutes in Italy, the Netherlands, Portugal, UK, and Spain. Results of 17 general chemistry analytes were evaluated across countries and across manufacturers according to performance specifications derived from biological variation (BV). RESULTS: For K, uric acid, glucose, cholesterol and high-density density (HDL) cholesterol, the minimum performance specification was met in all countries and by all manufacturers. For Na, Cl, and Ca, the minimum performance specifications were met by none of the countries and manufacturers. For enzymes, the situation was complicated, as standardization of results of enzymes toward RMPs was still not achieved in 20% of the laboratories and questionable in the remaining 80%. CONCLUSIONS: The overall performance of the measurement of 17 general chemistry analytes in European medical laboratories met the minimum performance specifications. In this general picture, there were no significant differences per country and no significant differences per manufacturer. There were major differences between the analytes. There were six analytes for which the minimum quality specifications were not met and manufacturers should improve their performance for these analytes. Standardization of results of enzymes requires ongoing efforts.

Effects of leptin and leptin receptor SNPs on clinical- and metabolic-related traits in apparent treatment-resistant hypertension.

Leptin is associated to the lack of blood pressure control as well as target organ damage in resistant hypertensive (RH) subjects. Single-nucleotide polymorphisms (SNPs) rs7799039 and rs1137101 in leptin (LEP) and leptin receptor (LEPR) genes, respectively, are associated with cardiovascular disease and metabolic syndrome. We evaluated the association of these two SNPs with clinical and biochemical features in 109 apparent treatment-RH subjects (aTRH) and 125 controlled hypertensives. Homozygous genotypes GG (n = 43) vs. AA (n = 14) for rs7799039 and AA (n = 34) vs. GG (n = 26) genotypes for rs1137101 were compared in aTRH subjects. There was no difference in leptin levels among both SNPs. On the other hand, LEP SNP (GG vs. AA) associated with the levels of glycated haemoglobin (6.4 ± 1.4 vs. 7.8 ± 2.3%, p = 0.03), insulin (8.6 ± 4.6 vs. 30.6 ± 27.7 uUI/mL, p = 0.01), HDL-cholesterol (51 ± 16 vs. 39 ± 11 mg/dL, p = 0.001) and PWV (9.5 ± 2.1 vs. 11.2 ± 2.8 m/s, p = 0.03). LEPR SNP (AA vs. GG), associated with heart rate (69 ± 12 vs. 67 ± 12 bpm, p = 0.03), fat mass (31 ± 11 vs. 24 ± 8 kg, p = 0.03) and triglycerides levels (175 ± 69 vs. 135 ± 75 mg/dL, p = 0.03). These findings may be clinically useful for identifying a group of aTRH who may have a LEP and/or LEPR gene variants, which may predispose this specific group to worse or better outcomes.

Crosstalk between obesity and MMP-9 in cardiac remodelling -a cross-sectional study in apparent treatment-resistant hypertension.

The balance between matrix metalloproteinases (MMP) and their tissue inhibitors (TIMP) plays a key role in the development of hypertension and obesity. We aimed to evaluate the levels of MMP-2 and 9 and TIMP-2 and -1 in obese and non-obese apparent treatment-resistant hypertensive subjects (aTRH) and its association with cardiac hypertrophy. This cross-sectional study enrolled 122 subjects and divided into obese aTRH (n = 67) and non-obese (n = 55) group. Clinical and biochemical data were compared between both groups, including office BP, ambulatory BP, plasma MMP-2 and 9, TIMP-2 and 1 and left ventricular mass index (LVMI). We found higher MMP-9 levels and MMP-9/TIMP-1 ratio in obese aTRH subjects but no difference in MMP-2 and TIMP-1 levels. Obesity influenced MMP-9 levels [ß = 20.8 SE =8.6, p = 0.02) independently of potential confounders. In addition, we found a positive correlation between MMP-9 and anthropomorphic parameters. Finally, obese aTRH subjects with left ventricular hypertrophy (LVH) had greater MMP-9 levels compared with non-obese with LVH. Our study suggests that MMP-9 levels are influenced by obesity and may directly participate in the progressive LV remodelling process, suggesting a possible role for a higher cardiovascular risk in apparent resistant hypertensive subjects.

Effect of oil palm on the Plecoptera and Trichoptera (Insecta) assemblages in streams of eastern Amazon.

The production of oil palm is expected to increase in the Amazon region. However, expansion of oil palm plantation leads to significant changes in the physical structure of aquatic ecosystems, mainly through the reduction of riparian vegetation that is essential for aquatic biodiversity. Here, we evaluated the effects of oil palm on the physical habitat structure of Amazonian stream environments and assemblages of Plecoptera and Trichoptera (PT), ​both found in these streams. We compared streams sampled in oil palm plantations (n = 13) with natural forest areas ("reference" streams, n = 8), located in the eastern Amazon, Brazil. Our results showed that oil palm streams were more likely to be in close proximity to roads, had higher pH values, and higher amounts of fine substrate deposited in the channel than reference streams. Further, these environmental changes had important effects on the aquatic invertebrate assemblages, reducing the abundance and richness of PT. Nevertheless, the genera composition of the assemblages did not differ between reference and oil palm (PERMANOVA, pseudo-F (1,19) = 1.891; p = 0.111). We conclude that oil palm production has clear negative impacts on aquatic environments and PT assemblages in Amazonian streams. We recommend that oil palm producers invest more in planning of road networks to avoid the construction of roads near to the riparian vegetation. This planning can minimize impacts of oil palm production on aquatic systems in the Amazon.

Deregulation of Soluble Adhesion Molecules in Resistant Hypertension and Its Role in Cardiovascular Remodeling.

BACKGROUND: Resistant hypertension (RHTN) and target organ damage are linked to increased inflammatory biomarkers, which may regulate adhesion molecules, such as intracellular adhesion molecule-1 (ICAM-1); vascular cell adhesion molecule-1 (VCAM-1); and the platelet (P-selectin) and endothelial (E-selectin) selectins. We investigated a previously unknown relationship between soluble P-selectin (sP-selectin), E-selectin (sE-selectin), ICAM-1 (sICAM-1) and VCAM-1 (sVCAM-1) with RHTN and target organ damage. METHODS AND RESULTS: We included 110 subjects diagnosed for true RHTN and 112 mild-moderate hypertensive (HTN) patients. Blood pressure parameters, pulse wave velocity and left ventricular mass index (LVMI) were measured. Adhesion molecules were measured on ELISA. Both sP-selectin and sE-selectin were increased; in contrast, sICAM-1 was reduced in RHTN compared with HTN patients, while similar sVCAM-1 was noted in the groups. sP-selectin and sVCAM-1 were elevated in the presence of arterial stiffness (sP-selectin: 104±47 vs. 89±45 ng/ml, P<0.05; sVCAM-1: 1,189±411 vs. 1,060±412 ng/ml, P<0.05) and cardiac hypertrophy (sP-selectin: 105±51 vs. 88±43 ng/ml, P<0.05; sVCAM-1: 1,170±433 vs. 1,040±383 ng/ml, P<0.05) in all HTN patients. sP-selectin was associated with target organ damage after adjustment for age and BP. Apart from potential confounders, sE-selectin was a significant indicator of RHTN. CONCLUSIONS: The adhesion molecule sP-selectin plays a role in cardiovascular damage, and sE-selectin in resistance to antihypertensive therapy. (Circ J 2016; 80: 1196-1201).

Ultrastructure and pollen morphology of Bromeliaceae species from the Atlantic Rainforest in Southeastern Brazil.

Pollen grain morphology of Bromeliaceae species collected in areas of the Atlantic Rainforest of southeastern Brazil was studied. The following species were analyzed: Aechmea bambusoides L.B.Sm. & Reitz, A. nudicaulis (L.) Griseb., A. ramosa Mart. ex Schult.f., Ananas bracteatus (Lindl.) Schult.f., Billbergia distachia (Vell.) Mez, B. euphemiae E. Morren, B. horrida Regel, B. zebrina (Herb.) Lindl., Portea petropolitana (Wawra) Mez, Pitcairnia flammea Lindl., Quesnelia indecora Mez, Tillandsia polystachia (L.) L., T. stricta Sol., T. gardneri Lindl., T. geminiflora Brongn. and Vriesea grandiflora Leme. Light and scanning electron microscopy were used and the species were grouped into three pollen types, organized according to aperture characteristics: Type I - pantoporate pollen grains observed in P. petropolitana, Type II - 2-porate pollen grains, observed in the genera Ananas, Aechmea and Quesnelia, and Type III - 1-colpate pollen grains, observed in the genera Billbergia, Pitcairnia, Tillandsia and Vriesea. Pollen data led to the construction of an identification key. The results showed that the species analyzed can be distinguished using mainly aperture features and exine ornamentation, and that these characteristics may assist in taxonomic studies of the family.

An international study of how laboratories handle and evaluate patient samples after detecting an unexpected APTT prolongation.

BACKGROUND: An unexpectedly detected prolonged activated partial thromboplastin time (APTT) can be a harmless laboratory finding, but can also reflect a thrombotic tendency or a bleeding disorder. The assistance of laboratory professionals in the interpretation of an unexpectedly detected prolonged APTT (uAPTT) is often required. The way in which uAPTTs are evaluated in laboratories was assessed in this international study with the aim of determining whether laboratory professionals are able to fulfill this need. METHODS: Postanalytical practices after uAPTT were investigated and the mixing study methodology (if used) was studied by circulating a case report with a questionnaire to staff in the invited laboratories. In addition, the interpretations of those staff regarding the presence or absence of inhibitors in three APTT mixing study scenarios were examined. RESULTS: Large within- and between-country variations were detected in both postanalytical practices and mixing study methodologies among the 990 responding laboratories, 90% of which were in 13 countries. Shortcomings regarding the investigation of uAPTTs leading to potentially incorrect or delayed clinical diagnoses were found in 88% of the laboratories. Of the laboratories to which the interpretative questions were sent, 49% interpreted all mixing study scenarios correctly. uAPTTs were investigated appropriately and all mixing study scenarios interpreted correctly in parallel in only 9.6% of the participating laboratories. CONCLUSIONS: The clinical requirement for the assistance of laboratory professionals in the interpretation of uAPTTs cannot be met at most of the participating laboratories. Laboratory professionals should be trained in the evaluation of ordinary laboratory tests, such as that for uAPTTs.

Increased arterial stiffness in resistant hypertension is associated with inflammatory biomarkers.

BACKGROUND: Increased levels of inflammatory biomarkers such as interleukin-6 (IL-6), 10 (IL-10), 1ß (IL-1ß), tumor necrosis factor-α (TNF-α) high-sensitivity C-reactive protein (hs-CRP) are associated with arterial stiffness in hypertension. Indeed, resistant hypertension (RHTN) leads to unfavorable prognosis attributed to poor blood pressure (BP) control and target organ damage. This study evaluated the potential impact of inflammatory biomarkers on arterial stiffness in RHTN. METHODS: In this cross-sectional study, 32 RHTN, 20 mild hypertensive (HTN) and 20 normotensive (NT) patients were subjected to office BP and arterial stiffness measurements assessed by pulse wave velocity (PWV). Inflammatory biomarkers were measured in plasma samples. RESULTS: PWV was increased in RHTN compared with HTN and NT (p < 0.05). TNF-α levels were significantly higher in RHTN and HTN than NT patients. No differences in IL-6 levels were observed. RHTN patients had a higher frequency of subjects with increased levels of IL-10 and IL-1ß compared with HTN and NT patients. Finally, IL-1ß was independently associated with PWV (p < 0.001; R(2) = 0.5; ß = 0.077). CONCLUSION: RHTN subjects have higher levels of inflammatory cytokines (TNF-α, IL-1ß and IL-10) as well as increased arterial stiffness, and detectable IL-1ß levels are associated arterial stiffness. These findings suggest that inflammation plays a possible role in the pathophysiology of RHTN.

Diurnal versus nocturnal pollination success in Billbergia horrida Regel (Bromeliaceae) and the first record of chiropterophily for the genus.

Billbergia horrida is endemic of the Atlantic Forest fragments in southeastern Brazil and characterized by flowers with typical traits for pollination by nocturnal animals. Although the majority of Billbergia species rely on diurnal pollination by hummingbirds, B. horrida is also visited by bats and this study evidences for the first time the occurrence of chiropterophily within the genus. The role of different groups of pollinators on the reproductive success of B. horrida was evaluated, as well as the correlation of nectar features in sustaining these animals during different periods of the day. Bats contributed to 82.1% of fruit set of B. horrida. Hummingbirds, in turn, contributed to only 10% of fruit set, and were poorly related to the reproductive success of this species. Amounts of nectar production and sugar concentration were similar to those of other chiropterophilous bromeliads and only the nectar volume changed significantly throughout the period of flower availability. Recurring visits by hummingbirds were probably because the flowers of B. horrida were open for 24h, offering energetic rewards for daytime visitors and due to the presence of other attractive bromeliad species growing at the same phorophyte and flowering at the same time.

Resistant or refractory hypertension: are they different?

Resistant hypertension (RHTN) consists in a condition where blood pressure (BP) levels remain uncontrolled despite the use of at least three drugs or if the control happens with four or more drugs. Throughout the last 50 years, it has been increasingly studied, and its phenotypes have been identified. The term refractory hypertension has been used concurrently with RHTN all those years, but in the last decade, it has been applied to the most afflicted part of RHTN--defined as the uncontrolled RHTN or as the uncontrolled RHTN who needs five or more drugs. Differences between those two phenotypes are being recently identified, especially classifying refractory subjects as having more: (1) cardiovascular risk, (2) target organ damage, (3) African-descending race, (4) coronary heart disease and myocardial ischemia, (5) aldosterone excess, (6) deregulation of adipokines, and (7) possible sympathetic hyperactivation. We review the most important studies in both resistant and refractory hypertension to gather the up-to-date data regarding the characteristics of these two high-risk groups of patients.

Tadalafil-induced improvement in left ventricular diastolic function in resistant hypertension.

PURPOSE: Left ventricular hypertrophy and diastolic dysfunction (LVDD) remain highly frequent markers of cardiac damage and risk of progression to symptomatic heart failure, especially in resistant hypertension (RHTN). We have previously demonstrated that administration of sildenafil in hypertensive rats improves LVDD, restoring phosphodiesterase type 5 (PDE-5) inhibition in cardiac myocytes. METHODS: We hypothesized that the long-acting PDE-5 inhibitor tadalafil may be clinically useful in improving LVDD in RHTN independently of blood pressure (BP) reduction. A single blinded, placebo-controlled, crossover study enrolled 19 patients with both RHTN and LVDD. Firstly, subjects received tadalafil (20 mg) for 14 days and after a 2-week washout period, they received placebo orally for 14 days. Patients were evaluated by office BP and ambulatory BP monitoring (ABPM), endothelial function (FMD), echocardiography, plasma brain natriuretic peptide (BNP-32), cyclic guanosine monophosphate (cGMP) and nitrite levels. RESULTS: No significant differences were detected in BP measurements. Remarkably, at least four echocardiographic parameters related with diastolic function improved accompanied by decrease in BNP-32 in tadalafil use. Although increasing cGMP, tadalafil did not change endothelial function or nitrites. There were no changes in those parameters after placebo. CONCLUSION: The current findings suggest that tadalafil improves LV relaxation through direct effects PDE-5-mediated in the cardiomyocytes with potential benefit as an adjunct to treat symptomatic subjects with LVDD such as RHTN patients.

The white-coat effect is an independent predictor of myocardial ischemia in resistant hypertension.

White-coat hypertension (WCH), commonly found in pseudoresistant hypertension, does not pose higher cardiovascular risk than hypertensive status. However, when the decrease of the out-of-office blood pressure does not reach normal levels - the white-coat effect (WCE) - the repercussions are still obscure. We investigated the repercussions of the WCE in myocardial perfusion in resistant hypertension (RHTN). We enrolled 129 asymptomatic RHTN subjects - divided into WCE (n = 63) and non-WCE (n = 66) - to perform rest and stress myocardial perfusion scintigraphy and biochemical tests. Groups were equal regarding age, gender and body mass index. There was a high prevalence of WCE (49%). WCE was associated with higher prevalence of myocardial ischemia (49.2% vs 7.6%, p < 0.001), microalbuminuria (60.3% vs 36.4%, p = 0.01) and higher heart rate (72 [64-80] vs 64 [60-69], p < 0.001), compared with non-WCE patients. On an adjusted logistic regression, heart rate was considered a predictor of WCE (OR = 1.10, 95% CI 1.04-1.15; p < 0.001), but not MA (OR = 1.8, 95% CI 0.8-3.9; p = 0.15). On a second model of adjusted logistic regression, WCE was an independent predictor of myocardial ischemia (OR = 14.7, 95% CI 4.8-44.8; p < 0.001). We found a high prevalence of WCE in RHTN, and this effect may predict silent myocardial ischemia in this subset of hypertensive patients. In this group of hypertensives special attention should be given to the WCE.

Trichoptera Life Stages Present Distinct Responses to Environmental Conditions in Amazonian Streams.

Biological communities have their biodiversity patterns affected by environmental, spatial, and biogeographic factors that vary from taxa to taxa, and often between life stages. This is especially true when there are differences in the habitat the species use in each of them. Individuals of the insect order Trichoptera are mostly aquatic in their larval stage and terrestrial in their adult stage, which may result in different behaviors and environmental requirements. Our goal was to evaluate the congruence between the larval and adult stages of Trichoptera in Amazonian streams regarding their abundance, richness, and assemblage composition. Additionally, we tried to identify the main environmental factors related to each life stage. For this, larvae and adults of Trichoptera were sampled in the same sites at 12 streams in the Caxiuanã National Forest, Pará state, Brazil. Adult assemblages had greater richness of genera and abundance of individuals than the larval ones, and there was no congruence in the genera composition between these life stages. Our results also showed that different environmental variables structured Trichoptera larvae and adults. Since the sampling of larvae and adults proved to be complementary in the studied streams, we advise that Trichoptera diversity surveys consider both life stages of these organisms.

Systematic challenges and opportunities in insect monitoring: a Global South perspective.

Insect monitoring is pivotal for assessing biodiversity and informing conservation strategies. This study delves into the complex realm of insect monitoring in the Global South-world developing and least-developed countries as identified by the United Nations Conference on Trade and Development-highlighting challenges and proposing strategic solutions. An analysis of publications from 1990 to 2024 reveals an imbalance in research contributions between the Global North and South, highlighting disparities in entomological research and the scarcity of taxonomic expertise in the Global South. We discuss the socio-economic factors that exacerbate the issues, including funding disparities, challenges in collaboration, infrastructure deficits, information technology obstacles and the impact of local currency devaluation. In addition, we emphasize the crucial role of environmental factors in shaping insect diversity, particularly in tropical regions facing multiple challenges including climate change, urbanization, pollution and various anthropogenic activities. We also stress the need for entomologists to advocate for ecosystem services provided by insects in addressing environmental issues. To enhance monitoring capacity, we propose strategies such as community engagement, outreach programmes and cultural activities to instill biodiversity appreciation. Further, language inclusivity and social media use are emphasized for effective communication. More collaborations with Global North counterparts, particularly in areas of molecular biology and remote sensing, are suggested for technological advancements. In conclusion, advocating for these strategies-global collaborations, a diverse entomological community and the integration of transverse disciplines-aims to address challenges and foster inclusive, sustainable insect monitoring in the Global South, contributing significantly to biodiversity conservation and overall ecosystem health. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.

Acute cardiac and hemodynamic effects of sildenafil on resistant hypertension.

PURPOSE: Failure to control blood pressure (BP) despite the use of three or more drugs characterizes resistant hypertension (RHTN). Impaired endothelial function is associated with this condition and phosphodiesterase-5 inhibitors (PDE5i)-inhibiting cGMP breakdown-reduce BP in RHTN patients. We hypothesized that acute administration of PDE5i could ameliorate hemodynamic, endothelial parameters and left ventricular diastolic function (LVDF) in RHTN patients. Also, an exploratory analysis was performed to assess the influence of the T-786C endothelial NO synthase polymorphism on those responses. METHODS: Subjects (n = 26) underwent a 6-month clinical screening for RHTN diagnosis. Increasing doses of oral sildenafil were given at 30 min intervals (37.5, 50 and 100 mg) while continuous non-invasive hemodynamic measures were assessed. LVDF, flow mediated dilation (FMD), nitrite and cGMP levels were also determined. RESULTS: Mean arterial pressure and total peripheral resistance decreased in all patients (84.17 ± 21.04 to 75 ± 17.21 mmHg; 1149 ± 459.7 to 1037 ± 340 dyn.s/cm(-5), respectively). Likewise, sildenafil improved diastolic dysfunction parameters (Left atrial volume: 25 ± 5.8 to 20 ± 4.4; IVRT: 104 ± 19.33 to 88 ± 15.22; E/e' septal: 9.7 ± 3.8 to 7.9 ± 2.9; E/e' lateral: 7.7 ± 3.4 to 6.4 ± 3.2). No statistical changes were found in FMD, nitrite and cGMP with PDE5i. CONCLUSION: Our data suggest PDE5i acutely improves diastolic function and hemodynamic profile in RHTN subjects, despite unchanging endothelial dysfunction.

Comparison of different methods of obtaining the rapid shallow breathing index.

OBJECTIVE: To compare the Rapid Shallow Breathing Index (RSBI) obtained by the ventilometer and from mechanical ventilation parameters. METHODS: Randomized crossover trial, including 33 intubated patients, on mechanical ventilation for at least 24 hours, undergoing spontaneous breathing test. Patients were submitted to the measurement of RSBI by four methods: disconnected from the ventilator through the ventilometer; in Pressure Support Ventilation (PSV) mode at a pressure of 7.ßcm H2O; in Continuous Positive Airway Pressure (CPAP) mode at a pressure of 5.ßcmH2O with flow trigger; in CPAP mode at a pressure of 5.ßcmH2O with pressure trigger. RESULTS: No significant difference was detected between the RSBI obtained by the ventilometer and in the CPAP mode with flow and pressure triggers, however, in the PSV mode, the values were lower than in the other measurements (p.ß<.ß0.001). By selecting patients from the sample with higher RSBI (... 80 cycles.min-1.L-1), the value of the index obtained by the ventilometer was higher than that obtained in the three options of ventilation methods. CONCLUSION: The RSBI obtained in the CPAP mode at a pressure of 5.ßcmH2O, in both triggers types, did not differ from that measured by the ventilometer; it is, therefore, an alternative when obtaining it from mechanical ventilation parameters is necessary. However, in the presence of borderline values, the RSBI measured by ventilometer is recommended, as in this method the values are significantly higher than in the three ventilation modalities investigated.