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1.
Environ Toxicol Chem ; 40(10): 2861-2873, 2021 10.
Article in English | MEDLINE | ID: mdl-34314524

ABSTRACT

The use of pesticides for plague control in agroecosystems generates a threat to wildlife and a major problem for human health. Pesticide compounds are also an important source of water and atmosphere contamination. Although insecticides are effective on their target organisms, they often affect organisms that are not their target. The aim of the present study was to research the effects of 3 types of neurotoxic insecticides-a pyrethroid (cypermethrin), a neonicotinoid (imidacloprid), and an organophosphate (chlorpyrifos)-on behavioral and physiological parameters of Pardosa saltans spider (Lycosidae). Our study analyzed for the first time the exploratory behavior of the spider mothers in the presence of these 3 insecticides on their egg-sacs and also on the ground. We also evaluated the oxidative stress effects on the juveniles hatched in the egg-sac protected by silk in relation to variations in detoxification enzymes (catalase, glutathione reductase, superoxide dismutase, glutathione-S-transferase, and glutathione peroxidase) and lipid peroxidation (reactive oxygen species [ROS]). The results show that these insecticides are repellents for mothers (cypermethrin is the most repellent), and maternal behavior is modified after detection of an insecticide on their egg-sac but mothers do not abandon their egg-sacs. These neurotoxic insecticides affect the juveniles inside their egg-sac. Cypermethrin and chlorpyrifos caused more oxidative stress in juveniles than did imidacloprid. The ROS generated by these insecticides seemed to be adequately eliminated by the juveniles' antioxidant systems. Environ Toxicol Chem 2021;40:2861-2873. © 2021 SETAC.


Subject(s)
Chlorpyrifos , Insecticides , Pesticides , Pyrethrins , Spiders , Animals , Chlorpyrifos/toxicity , Female , Glutathione Transferase/metabolism , Humans , Insecticides/toxicity , Mothers , Oxidative Stress , Pesticides/pharmacology , Pyrethrins/toxicity , Reactive Oxygen Species , Silk/pharmacology , Spiders/metabolism
2.
Pestic Biochem Physiol ; 165: 104559, 2020 May.
Article in English | MEDLINE | ID: mdl-32359558

ABSTRACT

Spiders are found among the most important predators of plague insects of numerous agricultural systems. They are the most numerous representatives of the Class Arachnid and are widely distributed in numerous ecosystems. Due to multiple variables, living beings are exposed to quantitative transitions of their energetic reserves, which affect their sensitivity before the different xenobiotics. In the present study we evaluate the effect of cypermethrin (pyrethroid) on different metabolic/energetic stages of the spider Polybetes pythagoricus (Sparassidae). We firstly studied LD50 of cypermethrin on young, males and, pre-vitellogenic and post-vitellogenic females. The activity of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione-S-transferase (GST) and acetylcholinesterase (AChE) was analyzed. Results indicate that young have a higher caloric content compared to adults, females have a higher caloric content than males and vitellogenesis generates a great calory decrease in females. The LD50 was significantly lower in young (10%) (103 ng/g weight) in relation to the three models of adults (969-1108 ng/g weight). Vitellogenesis causes an increase of free radicals as a result of the different metabolic processes which manifest as an increase in the lipid peroxidation. Doses at the LD30 and LD40 levels of cypermethrin did not generate alterations in any of the enzymes analyzed in young, this fact may probably provoke an increase of lipid peroxidation (evaluated as a great MDA increase). The activity of the enzymes linked to oxidative stress was altered by this doses in the three adult models, the enzymatic activity CAT, GR, and GST was sex-dependent. Post-vitellogenic females showed a greater activity of CAT, SOD, GST and GR before the xenobiotics than pre-vitellogenic ones, probably as a consequence of metabolic stress generated during vitellogenesis.


Subject(s)
Pyrethrins , Spiders , Animals , Antioxidants , Catalase , Ecosystem , Female , Glutathione , Glutathione Peroxidase , Glutathione Transferase , Lipid Peroxidation , Male , Oxidative Stress , Superoxide Dismutase
3.
J Comp Physiol B ; 190(3): 261-274, 2020 05.
Article in English | MEDLINE | ID: mdl-32078039

ABSTRACT

The aim of this study was to evaluate energetic source used by juveniles of a terrestrial oviparous invertebrate during the earliest periods of their life. Growth, behavioural activities and energy contents of Pardosa saltans spiderlings' residual vitellus were monitored during 8 days after their emergence from their egg-sac until they disperse autonomously. The life-cycle of juvenile after emergence can be divided into three periods: a gregarious while juveniles are aggregated on their mother, dismounting off their mother's back and dispersion. We present the first biochemical study of residual vitellus and energy expenditure during these three periods. At emergence, the mean weight of juveniles was 0.59 mg and energy stock from residual vitellus averaged 51 cal/g wet mass. During gregarious period, the weight of the juveniles aggregated on their mother did not vary significantly and juveniles utilized only 1 cal/day from their residual vitellus. During the period from dismounting until their first exogenous feed, juveniles lost weight and used 30% of their residual vitellus stock. Proteins from the residual vitellus contributed principally to their energy expenditure during this period: 1.5 µg protein/day. Juveniles' first exogenous feeding was observed 7-8 days after emergence, when 70% of residual vitellus energy had been utilized. Juveniles dispersed after eating, reconstituting an energy stock comparable to that observed at emergence from egg-sac (50 cal/g wet mass). This new energy stock contains mainly lipids unlike the energy stock from the residual vitellus.


Subject(s)
Arthropod Proteins/analysis , Egg Proteins/analysis , Energy Metabolism , Lipids/analysis , Ovum/chemistry , Spiders/physiology , Animals , Carbohydrates/analysis , Female , Predatory Behavior
4.
J Comp Physiol B ; 189(3-4): 335-350, 2019 08.
Article in English | MEDLINE | ID: mdl-30953127

ABSTRACT

Vitellogenesis represents one of the most vital processes of oviparous species during which various proteins, carbohydrates, and lipids are synthesized and stored inside the developing oocytes. Through analyzing protein changes in the midgut diverticula, hemolymph, and ovaries of females throughout the different vitellogenic stages of the spider Polybetes pythagoricus, we determined the origin of the different proteins involved in the formation of lipovitellins (LVs) along with the existence of a linkage between the hemocyanin and this vital process. An increase in the total protein content of the midgut diverticula, hemolymph, and ovary occurred throughout vitellogenesis followed by a decrease in those levels after laying. The presence of hemocyanin in egg and in LV2, as well as its accumulation in the ovary throughout the vitellogenesis process, was determined. Considering that all biologic processes depend on the correct structure and function of proteins, this study establishes, for the first time for the Order Araneae, the coexistence of three different origins of vitellogenesis-related proteins: one predominantly ovarian involving peptides of 120, 75, 46, and 30 kDa; another extraovarian one originated from the midgut diverticula and represented by a 170 kDa peptide, and a third hemolymphatic one, represented by the 67 kDa peptide.


Subject(s)
Gene Expression Regulation, Developmental/physiology , Spiders/physiology , Vitellogenesis/physiology , Animals , Egg Proteins/genetics , Egg Proteins/metabolism , Female , Lipoproteins/genetics , Lipoproteins/metabolism , Male , Proteins/metabolism , Reproduction/physiology
5.
Br J Dermatol ; 178(5): 1119-1127, 2018 05.
Article in English | MEDLINE | ID: mdl-29315480

ABSTRACT

BACKGROUND: Iris naevi and iris freckles have a frequency of 4% and 50% in the European population, respectively. They are associated with dysplastic naevi, but few studies have examined their link to cutaneous melanoma. OBJECTIVES: To assess whether iris pigmented lesions are a predictive indicator for cutaneous melanoma. METHODS: This is a melanoma case-control study of 1254 European-background Australians. Sun exposure and melanoma history, a saliva sample for DNA analysis and eye photographs taken with a digital camera were collected from 1117 participants. Iris images were assessed by up to four trained observers for the number of iris pigmented lesions. The data were analysed for correlations between iris pigmented lesions and melanoma history. RESULTS: Case participants over the age of 40 had similar numbers of iris pigmented lesions to age matched controls (mean 5·7 vs. 5·2, P = 0·02), but in younger case and control participants there was a greater difference (mean 3·96 vs. 2·19, P = 0·004). A logistic regression adjusted for age, sex, skin, hair and eye colour, skin freckling and naevus count found that the presence of three or more iris pigmented lesions increases the melanoma risk 1·45-fold [95% confidence interval (CI) 1·07-1·95]. HERC2/OCA2 rs12913832 and IRF4 rs12203592 influenced both eye colour and the number of iris pigmented lesions. On the HERC2/OCA2 A/A and A/G genotype background there was an increasing proportion of blue eye colour when carrying the IRF4 T allele (P = 3 × 10-4 ) and a higher number of iris pigmented lesions with the IRF4 T/T homozygote (P = 3 × 10-9 ). CONCLUSIONS: Iris pigmented lesion count provides additional predictive information for melanoma risk above that from conventional risk factors.


Subject(s)
Iris Neoplasms/pathology , Melanoma/pathology , Nevus, Pigmented/pathology , Skin Neoplasms/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Eye Color/genetics , Female , Genotype , Guanine Nucleotide Exchange Factors/genetics , Humans , Interferon Regulatory Factors/genetics , Iris Neoplasms/genetics , Male , Melanoma/genetics , Melanosis/pathology , Middle Aged , Nevus, Pigmented/genetics , Phenotype , Skin Neoplasms/genetics , Skin Pigmentation/physiology , Ubiquitin-Protein Ligases , Young Adult
6.
J Comp Physiol B ; 188(2): 211-224, 2018 03.
Article in English | MEDLINE | ID: mdl-28761984

ABSTRACT

The development of Pardosa saltans wolf spiders inside an egg sac includes two periods: an embryonic period and a post-embryonic period after hatching. We investigated spiderlings' energy expenditure to assess energetic costs during the different embryonic and post-embryonic developmental stages during which they are confined within their egg sac. We focused on the following developmental stages: egg, embryonic stages 1 and 2, and two stages, separated by a moult, during post-embryogenesis inside the egg sac: "juvenile instars 1 and 2" until emergence of 2 instar juveniles from their egg sac. We present the first biochemical characterization of the vitellus of wolf spiders' eggs, embryos and juveniles. Lipovitellins (LV) are composed of four apolipoproteins of 116, 87, 70 and 42 kDa, respectively, and LV represent 35-45% of total protein during development. The principal LV lipids are triglycerides, phospholipids, free fatty acids and sterols. Egg caloric content averaged 127 cal/g (proteins: 91 cal/g, lipids: 33 cal/g, carbohydrates: 3 cal/g). During development from undivided egg to emerged "juvenile 2", 67% of proteins, 51% of carbohydrates and 49% of triglycerides stocks were depleted. At the end of the post-embryonic period, at emergence from egg sac, body energy stock of "juveniles 2" was 38% of the initial calorie stocks in the eggs.


Subject(s)
Spiders/embryology , Spiders/physiology , Animals , Arthropod Proteins/physiology , Egg Proteins/physiology , Embryo, Nonmammalian/physiology , Embryonic Development , Female , Lipids/physiology , Ovum/physiology
8.
Environ Sci Pollut Res Int ; 24(2): 1322-1337, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27771882

ABSTRACT

The present study analyzes a battery of biomarkers in the water bug Belostoma elegans from a stream polluted with organic matter (OMS), and another one considered as reference site (RS) during spring-summer season (December to March). Biochemical parameters of glucidic, lipidic and oxidative metabolic pathways were analyzed in males and females of this insect. In general, no significant differences were observed in all biomarkers assayed between both sexes, except lactate concentration which was higher in males than in females (p < 0.0006) in the first three months. About carbohydrate metabolism parameters, only pyruvate-kinase showed significant differences between insects collected in both streams (p < 0.05) during December. However, the total lipid content, saturated fatty acid, and mainly triacylglycerol were higher in insects from RS compared to those from OMS (p < 0.002) in all sampled months. Levels of lipoperoxidation, protein oxidation, reduced glutathione and glutathione-S-transferase activity showed no differences between insects collected from both streams. Nevertheless, the significant increase observed in superoxide dismutase and catalase activities (p < 0.004) could be due to the elevated oxidative metabolism in insects from RS compared to those from OMS with lower dissolved oxygen. Regarding those responding parameters, males accounted for the differences between the two sites during the study period. In conclusion, our results support that lipidic energetic reserves and antioxidant enzyme activities in B. elegans could be used as biomarkers of environmental pollution by organic matter.


Subject(s)
Environmental Monitoring , Hemiptera/metabolism , Water Pollutants, Chemical/analysis , Animals , Argentina , Biomarkers/metabolism , Environmental Monitoring/methods , Female , Fresh Water , Glutathione/metabolism , Male , Rivers , Seasons , Superoxide Dismutase/metabolism
9.
Eur J Orthod ; 30(2): 190-8, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18263890

ABSTRACT

Orthodontic treatment is mainly dependent on the loads developed by metal wires. The load developed by a buckled orthodontic wire is of great concern for molar distalization and cannot be simply derived from mechanical properties measured through classical tests (i.e. tensile, torsion, and bending). A novel testing method, based on the Eulerian approach of a simple supported beam, has been developed in order to measure the load due to buckling of orthodontic wires. Elastic titanium molybdenum alloy (TMA; SDS Ormco) and superelastic Nitinol (3M Unitek) and copper nickel-titanium (NiTi; SDS Ormco) wires, each having a rectangular cross section of 0.016 x 0.022 square inches (0.41 x 0.56 mm(2)), were used. The wires were activated and deactivated by loading and unloading. In order to analyse thermo-mechanical properties in buckling, mechanical tests were assisted by calorimetric measurements through differential scanning calorimetry (DSC). Statistical analysis to determine differences between the samples was undertaken using two-way analysis of variance (ANOVA) and Tukey's post hoc test, and one-way ANOVA to assess differences between the tested wires under similar conditions and different materials. The results suggest that the load due to buckling depends on material composition, wire length, the amount of activation, temperature, and deformation rate. The results can be considered as the lower bound for the loads experienced by teeth as far as a buckled wire is concerned. At a temperature higher than the austenite finish transition temperature, superelastic wires were strongly dependent on temperature and deformation rate. The effect due to an increase of deformation rate was similar to that of a decrease of temperature. Load variations due to temperature of a superelastic wire with a length of 20 mm were estimated to be approximately 4 g/degrees C. The high performance of an applied superelastic wire may be related to the high dynamics of the load in relation to temperature.


Subject(s)
Dental Alloys , Dental Stress Analysis/methods , Orthodontic Wires , Alloys , Analysis of Variance , Calorimetry, Differential Scanning , Copper , Elasticity , Materials Testing , Nickel , Stress, Mechanical , Titanium
11.
Int J Oral Maxillofac Surg ; 36(7): 583-7, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17368852

ABSTRACT

The aim of this longitudinal study was to determine the effects of orthognathic surgery on signs and symptoms of temporomandibular disorders (TMD) and on pressure pain thresholds (PPTs) of the jaw muscles. Fourteen consecutive class III patients undergoing pre-surgical orthodontic treatment were treated by combined Le Fort I osteotomy and bilateral sagittal ramus osteotomy. The clinical examination included the assessment of signs and symptoms of TMD and the assessment of PPTs of the masseter and temporalis muscles. Anamnestic, clinical and algometric data were collected during five sessions over a 1-year period. Seven out of 14 patients presented with disc displacement with reduction at baseline, whereas four patients (two of them were new cases) did so at the end of follow up (p>0.05). None of the patients were diagnosed with myofascial pain of the jaw muscles at the beginning or end of follow up. PPTs of the masseter and temporalis muscles did not change significantly from baseline values throughout the whole study period. The occurrence of signs and symptoms of TMD fluctuates with an unpredictable pattern after orthognathic surgery for class III malocclusions.


Subject(s)
Malocclusion, Angle Class III/surgery , Masseter Muscle/physiology , Pain Threshold/physiology , Temporal Muscle/physiology , Temporomandibular Joint Disorders/physiopathology , Adolescent , Adult , Facial Pain/physiopathology , Female , Follow-Up Studies , Humans , Joint Dislocations/physiopathology , Longitudinal Studies , Male , Mandible/surgery , Maxilla/surgery , Osteotomy/methods , Osteotomy, Le Fort/methods , Postoperative Complications , Range of Motion, Articular/physiology , Sound , Temporomandibular Joint Disc/physiopathology
12.
Prog Orthod ; 5: 4-17, 2004.
Article in English, Italian | MEDLINE | ID: mdl-15329744

ABSTRACT

A case of rehabilitation of an edentulous patient with loss of vertical dimension is presented here. This patient presents with a Class III dental and skeletal malocclusion with an anterior cross-bite. The objective of this case report is to demonstrate that an accurate assessment of vertical dimension is necessary for good rehabilitation. The original vertical dimension was determined by a series of tests including, kinesiographic, electromyographic and transcutaneous electronic neural stimulation (TENS). Subsequently, the lost vertical dimension was re-established orthodontically. These examinations revealed a general hypertonicity of masticatory muscles due to the lost vertical dimension. Additionally, radiographs of the temporomandibular joint showed anteriorly displaced condyles. Following the completion of orthodontic treatment osseointegrated implants were placed to restore the dental arches.


Subject(s)
Jaw, Edentulous, Partially/rehabilitation , Vertical Dimension , Adult , Dental Implants , Electromyography , Humans , Joint Dislocations/diagnostic imaging , Joint Dislocations/therapy , Male , Malocclusion, Angle Class III/therapy , Masseter Muscle/physiopathology , Muscle Hypertonia/therapy , Orthodontics, Corrective , Patient Care Planning , Radiography , Temporal Muscle/physiopathology , Temporomandibular Joint Disorders/diagnostic imaging , Temporomandibular Joint Disorders/therapy , Transcutaneous Electric Nerve Stimulation
14.
Am J Orthod Dentofacial Orthop ; 111(2): 141-8, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9057613

ABSTRACT

This report reviews the orthodontic treatment of a patient suffering from a metabolic disease controlled by medication. The patient also had periodontal problems on both hard and soft tissue support. The results of involvement of general medicine, periodontal surgery, and proper biomechanics is shown and the problems of the multidisciplinary treatment discussed.


Subject(s)
Malocclusion/therapy , Orthodontics, Corrective , Patient Care Team , Adolescent , Alveolar Process/pathology , Biomechanical Phenomena , Diastema/therapy , Female , Humans , Hypothyroidism/drug therapy , Incisor/abnormalities , Periodontal Diseases/complications , Periodontal Diseases/surgery , Thyroxine/therapeutic use , Tooth Abnormalities/complications , Tooth Eruption, Ectopic/complications , Tooth Movement Techniques
15.
Eur J Orthod ; 19(6): 629-36, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9458596

ABSTRACT

The present study investigated the effects of a recycling technique on orthodontic ceramic brackets by means of a scanning electron microscope analysis. The weight and dimension changes of brackets recycled one, five and ten times compared with new ones were evaluated. The results suggest that changes in weight (+4.27 mg), in buccal and base slot widths (-0.0013 inches), in slot depth (+0.0014 inches) and in the total bracket base area (+1.46 mm2) are of little clinical relevance. The shear bond strengths of recycled versus new ceramic brackets were then evaluated and compared. The mean values for new ceramic brackets and brackets recycled one, five and ten times were 15.52, 11.23, 10.10 and 10.04 MPa, respectively, indicating that recycled ceramic brackets provide shear bond strengths adequate for clinical use. Moreover, they exhibit bond failures mostly at the bracket/adhesive interface, without causing enamel damage.


Subject(s)
Ceramics/chemistry , Orthodontic Brackets , Acrylic Resins/chemistry , Adhesives/chemistry , Analysis of Variance , Bisphenol A-Glycidyl Methacrylate/chemistry , Chemical Phenomena , Chemistry, Physical , Dental Bonding , Dental Enamel/ultrastructure , Dental Stress Analysis/instrumentation , Equipment Failure , Equipment Reuse , Evaluation Studies as Topic , Humans , Materials Testing , Microscopy, Electron, Scanning , Resin Cements/chemistry , Stress, Mechanical , Surface Properties
16.
Mondo Ortod ; 15(6): 645-58, 1990.
Article in Italian | MEDLINE | ID: mdl-2074879

ABSTRACT

The knowledge of force systems which are produced by orthodontic appliance is one of precondition for a rationale Orthodontic pretreatment. This article describes the force system developing when a straight wire is placed in two nonalligned brackets, to examine to typodont what is analysed by Burstone and Koenig in their study on six Classes.


Subject(s)
Dental Stress Analysis , Orthodontic Appliances , Orthodontics, Corrective/methods , Orthodontic Wires
17.
Mondo Ortod ; 15(6): 707-14, 1990.
Article in Italian | MEDLINE | ID: mdl-2074888

ABSTRACT

The Authors describe the unusual super-elastic property of the Japanese NiTi alloy wire. They examine the clinical applications in relation to the relatively constant force delivered during the deactivation and in relation to the new possibility to shape wire which are offered by the Archmate Wire Bender.


Subject(s)
Dental Alloys , Nickel , Orthodontic Wires , Titanium , Dental Stress Analysis/instrumentation , Elasticity , Hot Temperature , Materials Testing/instrumentation , Tensile Strength
18.
Arch Stomatol (Napoli) ; 31(4): 693-705, 1990.
Article in Italian | MEDLINE | ID: mdl-2100481

ABSTRACT

The authors report two cases of severe dentofacial skeletal anomalies, that are analyzed with radiologic diagnostic methods during the treatment. The dentoskeletal variation followed to the orthodontic-surgical therapy and the possible relapses are described.


Subject(s)
Cephalometry , Malocclusion, Angle Class III/surgery , Adult , Female , Humans , Male , Malocclusion, Angle Class III/diagnostic imaging , Malocclusion, Angle Class III/therapy , Mandible/surgery , Orthodontics, Corrective , Osteotomy , Patient Care Planning , Prognathism/surgery , Radiography , Recurrence , Syndrome
19.
Arch Stomatol (Napoli) ; 31(4): 723-42, 1990.
Article in Italian | MEDLINE | ID: mdl-2100484

ABSTRACT

The skeletal characteristics of dento-alveolar malocclusions condition the orthodontic therapy plane and produce typical and recurrent variables in the final shape in "Tweed occlusion". The study effects with templates made out of cephalometric average values of treatment in the different dental malocclusions, shows direction and amount of therapeutics correction. The behaviour of upper and lower incisors to achieve the normal occlusion is in relation with the characteristics of Angle's Class and with the necessity of therapeutics dental extractions.


Subject(s)
Cephalometry , Incisor/physiopathology , Malocclusion/therapy , Orthodontics, Corrective/methods , Adolescent , Face/anatomy & histology , Female , Humans , Male , Tooth Extraction
20.
Arch Stomatol (Napoli) ; 31(4): 793-820, 1990.
Article in Italian | MEDLINE | ID: mdl-2100490

ABSTRACT

The authors, described the typical cranio-facial anomalies in the border-line cases, consider the possibilities of the orthodontic therapy or else of the alternative orthodontic-surgical therapy. The advantages and disadvantages are commented.


Subject(s)
Malocclusion/therapy , Orthodontics, Corrective/methods , Humans , Malocclusion/surgery , Orthognathic Surgical Procedures , Osteotomy , Tooth Extraction , Vertical Dimension
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