Tumour size in adrenal tumours: its importance in the indication of adrenalectomy and in surgical outcomes-a single-centre experience.

OBJECTIVE: To evaluate the relevance of tumour size in adrenal tumours in the estimation of malignancy risk and in the outcomes of adrenalectomy. METHODS: We evaluate the histological results and surgical outcomes (intraoperative and postsurgical complications) in a retrospective single-centre cohort of patients without history of active extraadrenal malignancy with adrenal tumours consecutively operated in our centre during January 2010 and December 2020. We compared these results in lesions smaller and larger than 40, 50, and 60 mm. RESULTS: Of 131 patients with adrenal tumours who underwent adrenalectomy, 76 (58.0%) had adrenal masses measuring ≥ 40 mm; 47 were > 50 mm and 28 > 60 mm. The final diagnosis was adrenocortical carcinoma (ACC) in 7 patients, pheochromocytoma in 35, and benign lesions in the remaining. All patients with ACC had adrenal masses > 50 mm, with Hounsfield units > 40 and low lipidic content in the CT. The risk of ACC and pheochromocytoma increased as tumour size did. The diagnostic accuracy of tumour size was quite good for the prediction of ACC (AUC-ROC 0.883). Nevertheless, when only adrenal tumours with HU < 40 were considered, the risk of ACC was 0% independent of tumour size. For pheochromocytomas, the risk was of 8.6% independent of tumour size for lesions with < 20HU. The risk of intraoperative and postoperative complications was independent of tumour size. CONCLUSION: Risk of malignancy and of pheochromocytoma increased as tumour size increased, but, in the presurgical estimation of malignancy risk and of pheochromocytoma, not only tumour size, also lipidic content and other radiological features, should be considered. The risk of complications was independent of tumour size, but hospital stay was longer in patients with complication or open approach.

Model reduction of genome-scale metabolic models as a basis for targeted kinetic models.

Constraint-based, genome-scale metabolic models are an essential tool to guide metabolic engineering. However, they lack the detail and time dimension that kinetic models with enzyme dynamics offer. Model reduction can be used to bridge the gap between the two methods and allow for the integration of kinetic models into the Design-Built-Test-Learn cycle. Here we show that these reduced size models can be representative of the dynamics of the original model and demonstrate the automated generation and parameterisation of such models. Using these minimal models of metabolism could allow for further exploration of dynamic responses in metabolic networks.

Protocol for presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas: a multidisciplinary approach.

OBJECTIVE: To offer a practical guide for the presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas (PGLs). METHODS: This protocol was based on a comprehensive review of the literature and on our own multidisciplinary team's experience from managing pheochromocytoma and sympathetic PGLs at a referral center. RESULTS: Patients with pheochromocytomas and sympathetic paragangliomas (PGLs) may develop potentially life-threatening complications, especially during surgical procedures. A complete biochemical, radiological, genetic, and cardiological assessment is recommended in the preoperative stage as it provides an evaluation of the risk of surgical complications and malignancy, allowing individualization of the presurgical treatment. Treatment with α-blockade and proper volume expansion in the preoperative stage significantly reduces the perioperative morbidity. During surgery, the anesthesiologist should look for a deep anesthetic level that inhibits the cardiovascular effects of catecholamines to minimize the risk of intraoperative complications. CONCLUSIONS: An optimal presurgical evaluation of pheochromocytomas/ sympathetic PGL requires a multidisciplinary approach, including a complete hormonal, radiological, cardiac, genetic, and functioning evaluation in most cases. A proper preoperative evaluation in combination with strict blood pressure and heart rate control, and blood volume status optimization, will significantly reduce the risk of intraoperative and perioperative complications. In those patients who unfortunately develop intraoperative complications, the role of the anesthesiologist is essential since the selection of the appropriate management has a direct impact on morbimortality reduction.

Systemic administration of probiotics reduces the severity of apical periodontitis.

AIM: To evaluate the effect of systemic administration of probiotics on the severity of apical periodontitis (AP). METHODOLOGY: Twenty-four male Wistar rats were used. AP was induced in the maxillary left/right first molars. The animals were arranged into groups: Control, Lactobacillus rhamnosus, and Lactobacillus acidophilus. Probiotics were administered orally for gavage (109 colony-forming units diluted in 5 mL of water for 30 days) during the development of AP. After 30 days, cardiac puncture was performed to analyse the complete blood count. Moreover, microbiological analysis of the root canal contents and saliva was performed. Then, the animals were euthanized and the jaw removed for histopathological and IL-10, IL-1ß and IL-6 immunolabeling analyses. After the Shapiro-Wilk test of normality, the Kruskal-Wallis followed by Dunn's test was performed for nonparametric data, and analysis of variance followed by the Tukey test was performed for parametric data (P < 0.05). RESULTS: No significance difference was observed in the blood profiles and in the counts of microorganisms from the saliva samples among the groups (P > 0.05). Total microorganism counts in the root canal, the inflammatory infiltrate and the immunostaining for IL-1ß and IL-6 in AP were significantly lower in the probiotic groups when compared with the control group (P < 0.05). IL-10 was significantly more immunolabled in the probiotic groups than in the control group (P < 0.05). CONCLUSION: Supplementation with probiotics (Lactobacillus rhamnosus and Lactobacillus acidophilus) had a significant effect on the severity of apical periodontitis in rats, demonstrating the anti-inflammatory effect of probiotics on the development of apical periodontitis.

Diabetes and necrotizing soft tissue infections-A prospective observational cohort study: Statistical analysis plan.

BACKGROUND: Necrotizing soft tissue infections (NSTIs) are rare but carry a high morbidity and mortality. The multicenter INFECT project aims to improve the understanding of the pathogenesis, clinical characteristics, diagnosis, and prognosis of NSTIs. This article describes the study outline and statistical analyses that will be used. METHODS: Within the framework of INFECT project, patients with NSTI at 5 Scandinavian hospitals are enrolled in a prospective observational cohort study. The goal is to evaluate outcome and characteristics for patients with NSTI and diabetes compared to patients with NSTI without diabetes. The primary outcome is mortality at 90 days after inclusion. Secondary outcomes include days alive and out of ICU and hospital, SAPS II, SOFA score, infectious etiology, amputation, affected body area, and renal replacement therapy. Comparison in mortality between patients with diabetes type 1 and 2 as well as between insulin-treated and non-insulin-treated diabetes patients will be made. Clinical data for diabetic patients with NSTI will be reported. CONCLUSION: The study will provide important data on patients with NSTI and diabetes.

Necrotizing soft tissue infections - a multicentre, prospective observational study (INFECT): protocol and statistical analysis plan.

BACKGROUND: The INFECT project aims to advance our understanding of the pathophysiological mechanisms in necrotizing soft tissue infections (NSTIs). The INFECT observational study is part of the INFECT project with the aim of studying the clinical profile of patients with NSTIs and correlating these to patient-important outcomes. With this protocol and statistical analysis plan we describe the methods used to obtain data and the details of the planned analyses. METHODS: The INFECT study is a multicentre, prospective observational cohort study. Patients with NSTIs are enrolled in five Scandinavian hospitals, which are all referral centres for NSTIs. The primary outcomes are the descriptive variables of the patients. Secondary outcomes include identification of factors associated with 90-day mortality and amputation; associations between affected body part, maximum skin defect and Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score and 90-day mortality; 90-day mortality in patients with and without acute kidney injury (AKI) and LRINEC score of six and above or below six; and association between affected body part at arrival and microbiological findings. Exploratory outcomes include univariate analyses of baseline characteristics associations with 90-day mortality. The statistical analyses will be conducted in accordance with the predefined statistical analysis plan. CONCLUSION: Necrotizing soft tissue infections result in severe morbidity and mortality. The INFECT study will be the largest prospective study in patients with NSTIs to date and will provide important data for clinicians, researchers and policy makers on the characteristics and outcomes of these patients.

The effects of tracheal tube cuffs filled with air, saline or alkalinised lidocaine on haemodynamic changes and laryngotracheal morbidity in children: a randomised, controlled trial.

We studied the effects of tracheal tube cuffs filled with air, saline or alkalinised lidocaine on haemodynamic changes during tracheal extubation and postoperative laryngotracheal morbidity in children. We randomly allocated 164 children aged 3-13 years undergoing general anaesthesia to one of four groups; tracheal tube cuffs filled with air (n = 41); saline (n = 41); alkalinised lidocaine 0.5% (n = 41); or alkalinised lidocaine 1% (n = 41). Intracuff pressure was monitored and maintained below 20 cmH2 O. The mean (SD) increases in systolic blood pressure after tracheal extubation compared with before extubation were 10.9 (10.8) mmHg, 7.3 (17.7) mmHg, 4.1 (10.5) mmHg and 1.9 (9.5) mmHg in the air, saline, 0.5% and 1% alkalinised lidocaine groups, respectively (p = 0.021). The mean (SD) increases in diastolic blood pressure after tracheal extubation compared with before extubation were 3.9 (9.7) mmHg, 7.9 (14.6) mmHg, 0.7 (10.4) mmHg and 3.6 (6.9) mmHg in the air, saline, 0.5% and 1% alkalinised lidocaine groups, respectively (p = 0.019). The mean (SD) increases in heart rate after tracheal extubation compared with before extubation were 14.2 (7.6) beats.min-1 , 15.5 (13.1) beats.min-1 , 5.2 (9.6) beats.min-1 and 4.1 (6.6) beats.min-1 in the air, saline, 0.5% and 1% alkalinised lidocaine groups, respectively (p < 0.001). The incidence of sore throat 8 h after tracheal extubation was 22.0% in the air-filled group, 9.8% in the saline group, 4.9% in the 0.5% alkalinised lidocaine group and 2.4% in the 1% alkalinised lidocaine group, p = 0.015. We conclude that filling the tracheal tube cuff with alkalinised lidocaine-filled reduces the haemodynamic response to tracheal extubation and postoperative laryngotracheal morbidity in children.

Maize endophytic bacteria as mineral phosphate solubilizers.

In the present study, we demonstrated the in vitro activity of endophytic phosphate-solubilizing bacteria (PSB). Fifty-five endophytic PSB that were isolated from sap, leaves, and roots of maize were tested for their ability to solubilize tricalcium phosphate and produce organic acid. Partial sequencing of the 16S rRNA-encoding gene showed that the isolates were from the genus Bacillus and different species of Enterobacteriaceae. The phosphate solubilization index on solid medium and phosphate solubilization in liquid medium varied significantly among the isolates. There was a statistically significant difference (P ≤ 0.05) for both, the values of phosphate-solubilizing activity and pH of the growth medium, among the isolates. Pearson correlation was statistically significant (P ≤ 0.05) between P-solubilization and pH (R = -0.38), and between the gluconic acid production and the lowering of the pH of the liquid medium at 6 (R = 0.28) and 9 days (R = 0.39). Gluconic acid production was prevalent in all the PSB studied, and Bacillus species were most efficient in solubilizing phosphate. This is the first report on the characterization of bacterial endophytes from maize and their use as potential biofertilizers. In addition, this may provide an alternative strategy for improving the phosphorus acquisition efficiency of crop plants in tropical soils.

Impaired CD23 and CD62L expression and tissue inhibitors of metalloproteinases secretion by eosinophils in adults with atopic dermatitis.

BACKGROUND: Eosinophils are multifunctional, polymorphonuclear leucocytes that secrete proteins within cytoplasmic granules, such as cytokines, chemokines, metalloproteinases (MMPs) and metalloproteinases tissue inhibitors (TIMPs). Although eosinophilia is a hallmark of atopic dermatitis (AD), several functional aspects of eosinophils remain unknown. OBJECTIVE: We aimed to evaluate the phenotype and functional response of eosinophils under staphylococcal enterotoxin B (SEB) and Toll-like receptor (TLR)-2/6 (FSL-1) stimulation in the secretion of CCL5, MMPs and TIMPs in adults with AD. METHODS: Forty-one adult patients with AD and 45 healthy controls enrolled for the study. Phenotype of eosinophils from granulocytes of peripheral blood was analysed by flow cytometry. We performed evaluation of CCL5 (cytometric bead array), MMP and TIMP (ELISA) secretion, in culture supernatants of purified eosinophils stimulated with SEB or TLR2/6 agonist (FSL-1). RESULTS: We found a higher frequency of LIN1- CCR3+ eosinophils, and decreased expression of CD23 and CD62L receptors in eosinophils of AD patients. There was no difference in MMP and TIMP serum levels between the evaluated groups. However, we detected decreased basal levels of TIMP-1, TIMP-2 and CCL5 in culture supernatants from purified, unstimulated eosinophils from AD patients. CONCLUSION: In adults with AD, phenotypical features of eosinophils reveal decreased expression of early activation and L-selectin receptors. Regarding the functional profile of purified eosinophils related to tissue remodelling in atopic dermatitis, innate immune stimulation (TLR2/6 agonist and SEB) did not affect the ratio of MMP/TIMPs secretion in AD. Our findings reinforce the potential breakdown in tissue remodelling process mediated by eosinophils in AD.

Relationship between galactomannan structure and physicochemical properties of films produced thereof.

In this work five sources of galactomannans, Adenanthera pavonina, Cyamopsis tetragonolobus, Caesalpinia pulcherrima, Ceratonia siliqua and Sophora japonica, presenting mannose/galactose ratios of 1.3, 1.7, 2.9, 3.4 and 5.6, respectively, were used to produce galactomannan-based films. These films were characterized in terms of: water vapour, oxygen and carbon dioxide permeabilities (WVP, O 2 P and CO 2 P); moisture content, water solubility, contact angle, elongation-at-break (EB), tensile strength (TS) and glass transition temperature (T g ). Results showed that films properties vary according to the galactomannan source (different galactose distribution) and their mannose/galactose ratio. Water affinity of mannan and galactose chains and the intermolecular interactions of mannose backbone should also be considered being factors that affect films' properties. This work has shown that knowing mannose/galactose ratio of galactomannans is possible to foresee galactomannan-based edible films properties.

Is Neoseiulus wearnei the Neoseiulus californicus of Australia?

Species of the family Phytoseiidae are known as predatory mites, some of them being used in crops to control mite pests, all around the world. Neoseiulus (=Cydnodromus) californicus is among the most commonly used Phytoseiidae species in biological control programs, especially in vineyards, orchards and vegetable fields. This species is distributed world-wide but has never been reported from Australia. On the other hand, specimens morphologically close to N. californicus have been assigned to a species called Neoseiulus wearnei, only reported from Australia. Investigations based on morphological and molecular comparisons were carried out to investigate whether these two taxa are conspecific. Morphological analyses showed no significant difference between specimens identified as N. wearnei and N. californicus. Similarly, genetic distances between these taxa were null, showing that all these specimens belong to the same species. Although it is not yet possible to conclude that all the specimens identified as N. wearnei are N. californicus, we can conclude that N. californicus is present in Australia. The information about the biology of N. californicus can thus now be applied to the Australian population of this species for biological control purposes.

Spectrophotometric Analysis of Apical Extrusion of Sodium Hypochlorite using Different Irrigation Protocols in an Ex Vivo Model of Immature Teeth.

OBJECTIVE: To evaluate the effect of different agitation methods on apical extrusion of 1.5% sodium hypochlorite (NaOCl) in an ex vivo model of immature teeth. METHODS: Sixty extracted human inferior incisors were prepared to simulate immature teeth and embedded in an artificial root socket made of silicone impression material. The teeth were then divided into four groups: Conventional needle irrigation (CNI) alone, CNI supplemented with Ultrasonic Irrigant Activation (UIA), EasyClean (EC), or XP-endo Finisher (XPF). Extruded NaOCl was collected, reacted with m-cresol purple, and its absorbance values were measured. The data were statistically analyzed using One-way analysis of variance with a significance level of 5%. RESULTS: All groups showed apically extruded irrigating solution, and the mean volumes of extruded NaOCl did not differ significantly between any of the test groups (p⟩0.05). CONCLUSION: The activation of 1.5% NaOCL by UIA, EC, or XPF as supplementary to CNI does not promote greater apical extrusion when compared to CNI alone in simulated immature teeth.

Two women with cerebral venous thrombosis: oral contraceptives?

Two cases of cerebral venous thrombosis are reported. Patients were apparently healthy 39 and 28-year old females with non-specific presenting features. Image findings were characteristic of cerebral sinus thrombosis. The younger patient received progesterone to treat placental abruption eight years previously; she had cerebral venous thrombosis while using oral contraception. Both patients had used contraceptive pills for a long time. Oral hormonal contraceptives may increase the risk of vascular events, even in people without personal or family history of venous thrombosis. Modern imaging methods have contributed to early diagnosis, but the possibility of under diagnosis still persists. This report aims to increase the awareness of health-workers about cerebral venous thrombosis in women, an entity often misdiagnosed, under diagnosed and under-reported.

Surgical and postsurgical management of abdominal paragangliomas and pheochromocytomas.

PURPOSE: To describe our current protocol for surgical and postsurgical management of abdominal paragangliomas (PGLs) and pheochromocytomas, with a special focus on multidisciplinary management in centres with experience. METHODS: The physicians involved in the management of patients with abdominal PGLs and pheochromocytomas of our hospital reviewed systematically current knowledge on the surgical management of abdominal PGLs and pheochromocytomas. RESULTS: Currently, surgery is considered the treatment of choice for abdominal PGLs and pheochromocytomas. The choice of surgical approach is determined based on the location of the lesion, size, patient́s body habitus and the likelihood of malignancy. Laparoscopic surgery is usually considered the gold standard approach for pheochromocytomas, but open access should be considered in invasive and/or potentially malignant tumours >8-10 cm and for abdominal PGLs. Postsurgical management of pheochromocytomas and PGLs includes close hemodynamic monitoring and treatment of postsurgical complications, the pathological study of the surgical specimen, reassessment of hormonal and/or radiological status and planning of follow-up based on the risk of recurrence and malignancy. CONCLUSION: Surgery represents the treatment of choice of most abdominal PGLs and pheochromocytomas. Optimal postsurgical evaluation, including hemodynamic, pathological, hormonal, and radiological evaluation, should be performed by a multidisciplinary team specializing in PGL/pheochromocytoma management.

Clinical Usefulness of Prostate-specific Membrane Antigen-ligand Positron Emission Tomography/Computed Tomography for the Detection of Prostate Cancer Biochemical Recurrence after Primary Radiation Therapy in Patients with Prostate-specific Antigen Below the Phoenix Threshold: Systematic Review and Meta-analysis.

AIMS: After primary radiotherapy, biochemical recurrence is defined according to the Phoenix criteria as a prostate-specific antigen (PSA) value >2 ng/ml relative to the nadir. Several studies have shown that prostate-specific membrane antigen (PSMA)-ligand positron emission tomography/computed tomography (PET/CT) can help in detecting recurrence in patients with low PSA values. This study aimed to assess the detection rate and patterns of PSMA-ligand PET/CT uptake in patients with suspected biochemical recurrence after primary radiotherapy and with PSA levels below the Phoenix threshold. MATERIALS AND METHODS: The meta-analysis was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Articles providing data on patients with suspected prostate cancer recurrence after primary radiotherapy with a PSA value below the Phoenix threshold and who underwent PSMA-ligand PET/CT were included. Quality assessment was carried out using the Quality Assessment of Diagnostic Accuracy Studies-2 tool (QUADAS-2). RESULTS: In total, five studies were included, recruiting 909 patients (202 with PSA ≤2 ng/ml). The PSMA-ligand detection rate in the patients with ≤2 ng/ml ranged from 66 to 83%. The most frequent source of PSMA-ligand PET/CT uptake was local recurrence, followed by lymph node metastasis and bone metastasis. PSMA-ligand PET/CT uptake due to local-only recurrence was more likely in patients with PSA ≤2 ng/ml compared with PSA > 2 ng/ml: risk ratio 0.72 (95% confidence interval 0.58-0.89), P = 0.003. No significant differences were observed in the detection of PSMA-ligand uptake in other areas. Limitations include a lack of biopsy confirmation, cohort reports with small sample sizes and a potentially high risk of bias. CONCLUSION: A significant detection of PSMA-ligand-avid disease was observed in patients with PSA levels below the Phoenix threshold. There was a higher likelihood of detecting local-only uptake when the PSA value was ≤2 ng/ml. The findings suggest that a critical review of the Phoenix criteria may be warranted in the era of PSMA-ligand PET/CT and highlight the need for further prospective trials.

Metabolic syndrome in calcium oxalate stones: Is it so important in this type of lithiasis?

INTRODUCTION AND OBJECTIVE: The association of the metabolic syndrome with lithogenesis has been described, especially in uric acid stones. The aim of the work was to analyze the role of the metabolic syndrome in oxalocalcic lithogenesis. MATERIALS AND METHODS: Metabolic evaluation of 151 patients including biochemical, hormonal and 24-urine urine parameters, as well as characteristics associated with metabolic syndrome. The relationship between the characteristics associated with the metabolic syndrome and those related to lithogenesis was evaluated using Spearman's correlation coefficient (SCC), Student's t test and Fisher's exact test. RESULTS: The average body mass index (BMI) was 25.9 (SD 3.7). The median age was 51 years (18.6-84.8) and 64.9% were men. There were no statistically significant differences between hypertension and estradiol, testosterone, triglycerides or cholesterol (P=.191, .969, .454, .345, respectively). Regarding glucose, the mean was 114.5 and 93.5mg/dl in patients with and without hypertension (P=.000). The levels of glucose, estradiol, testosterone or cholesterol did not vary with proteinuria (P=.518, P=.227, P=.095, P=.218, respectively). The mean triglycerides were 185.6 and 108.2mg/dl in patients with and without proteinuria (P=.001). Hypertension and proteinuria were not associated (P=.586). BMI correlated with serum and urinary uric acid and urinary creatinine. CONCLUSIONS: There are few associations between the characteristics of the metabolic syndrome and the anomalies related to lithogenesis. Metabolic syndrome does not seem to have a relevant role in the development of oxalocalcic stones.

A limited LCA of bio-adipic acid: manufacturing the nylon-6,6 precursor adipic acid using the benzoic acid degradation pathway from different feedstocks.

A limited life cycle assessment (LCA) was performed on a combined biological and chemical process for the production of adipic acid, which was compared to the traditional petrochemical process. The LCA comprises the biological conversion of the aromatic feedstocks benzoic acid, impure aromatics, toluene, or phenol from lignin to cis, cis-muconic acid, which is subsequently converted to adipic acid through hydrogenation. Apart from the impact of usage of petrochemical and biomass-based feedstocks, the environmental impact of the final concentration of cis, cis-muconic acid in the fermentation broth was studied using 1.85% and 4.26% cis, cis-muconic acid. The LCA focused on the cumulative energy demand (CED), cumulative exergy demand (CExD), and the CO(2) equivalent (CO(2) eq) emission, with CO(2) and N(2) O measured separately. The highest calculated reduction potential of CED and CExD were achieved using phenol, which reduced the CED by 29% and 57% with 1.85% and 4.26% cis, cis-muconic acid, respectively. A decrease in the CO(2) eq emission was especially achieved when the N(2) O emission in the combined biological and chemical process was restricted. At 4.26% cis, cis-muconic acid, the different carbon backbone feedstocks contributed to an optimized reduction of CO(2) eq emissions ranging from 14.0 to 17.4 ton CO(2) eq/ton adipic acid. The bulk of the bioprocessing energy intensity is attributed to the hydrogenation reactor, which has a high environmental impact and a direct relationship with the product concentration in the broth.

Massive pleural effusion due to metastasis of prostate cancer.

We describe the case of a 72-year old male with pleural effusion associated with prostate cancer. There was a previous history of tobacco smoking (pack/year: 47) and of total prostatectomy followed by external beam radiation therapy seven years previously for prostate cancer. Furthermore, he was submitted to orchiectomy plus non-steroidal anti-androgen blockage, in addition to docetaxel-based chemotherapy and prednisone. After the beginning of chemotherapy, a progressive elevation in prostate specific antigen (PSA) levels was observed. On admission, he presented with fever, weight loss, and respiratory symptoms due to a massive right pleural effusion. Fluid samples obtained by needle aspiration showed haemorrhagic exudates without malignant cells. Pleural metastasis were detected by thorax imaging studies, and biopsy samples revealed prostate adenocarcinoma as the origin of his pleural effusion. Pleural fluid was drained and talc pleurodesis was performed. This report aims to describe the occurrence of massive pleural effusion due to metastasis of prostate cancer and emphasizes the role of pleural biopsy with immunohistochemical studies to characterize this diagnosis.

Herbivory and leaf traits of Amazonian tree species as affected by irradiance.

Herbivory is one of the major biotic stress factors that affect the establishment of plants. However, the main factors that drive herbivory in seedlings of Amazonian tree species are still not well understood. Here we investigated whether contrasting levels of irradiance influence herbivory according to different herbivory indicators and which leaf traits are most related to interspecific variation in herbivory under contrasting irradiance conditions. We measured the leaf area lost as a result of insect herbivory in five tree species planted in a silvicultural system of secondary forest enrichment according to two indicators, herbivore damage (accumulated since plant germination) and herbivory rate (measured over time), and two irradiance conditions, understorey PPFD 2.6 mol·m-2 ·day-1 ) and gap PPFD 33.1 mol·m-2 ·day-1 . Furthermore, we related the interspecific variation in herbivory to a set of leaf traits: SLA, RWC, sclerophylly, phenolic compound content, tannins, condensed tannins and non-structural carbohydrates. Herbivore damage was significantly affected by light availability and species, with the highest percentage variation observed in the Meliaceae (Carapa guianensis and Swietenia macrophylla). For the herbivory rate, only the interspecific variation was significant, with Bertholletia excelsa having the lowest rates. Chemical characteristics (phenolic compounds and tannins) were most related to herbivory rates, as well as highly influenced by light conditions. Non-structural carbohydrates (starch and sucrose) were also related to the interspecific variation in herbivory. The phenolic compounds and starch, as affected by light quantity, are species dependent. Thus, the selective pressure on herbivores may be driven by species-dependent responses to light conditions.

Ex vivo evaluation of the accuracy and coefficient of repeatability of three electronic apex locators using a simple mounting model: a preliminary report.

AIM: To compare ex vivo the accuracy and coefficient of repeatability of three electronic apex locators in locating the apical constriction. METHODOLOGY: Thirty-one single-rooted teeth were used. The teeth were sectioned at the cement--enamel junction. A mounting model was used for the measurement of electronic length (EL). The Root ZX-II, the Mini Apex Locator and the Novapex were used for electronic measurements. Each electronic measurement was obtained and repeated. After the last measurement, the file was cemented in place, and the apical 4 mm of each root canal was exposed. The distance from the tip of the file to the apical constriction was determined by three investigators and compared with the corresponding ELs. RESULTS: The coefficient of repeatability of all devices was acceptable: Root ZX-II, 0.04 mm; Mini Apex Locator, 0.10 mm; and Novapex, 0.08 mm. There was little variation in inter-examiner agreement; the rho(C) (Lin) correlation coefficient was 0.83 for examiners 1 and 2, 0.88 for examiners 1 and 3 and 0.99 for examiners 2 and 3. Using the Root ZX-II, 13 of 31 electronic measurements were located at the apical constriction (42%). Otherwise, the tip of the file was not located at the apical constriction in any of the electronic measurements with the other two devices. The Wilcoxon signed rank test did not reveal any statistical difference between the Root ZX-II measurements and the actual length (P = 0.628), but there was a statistical difference between the Mini Apex Locator and Novapex measurements and the actual length position (P < 0.05). CONCLUSIONS: The devices tested in this study had a high coefficient of repeatability. The Root ZX-II was accurate, but the Mini Apex Locator and Novapex were not accurate in locating the apical constriction.