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2.
Biomed Pharmacother ; 142: 112006, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34392085

ABSTRACT

P2X7 receptor promotes inflammatory response and neuropathic pain. New drugs capable of impairing inflammation and pain-reducing adverse effects extracted from plant extracts have been studied. Physalis angulate L. possesses traditional uses and exhibits antiparasitic, anti-inflammatory, antimicrobial, antinociceptive, antimalarial, antileishmanial, immunosuppressive, antiasthmatic. diuretic, and antitumor activities. The most representative phytochemical constituents identified with medicinal importance are the physalins and withanolides. However, the mechanism of anti-inflammatory action is scarce. Although some physalins and withanolides subtypes have anti-inflammatory activity, only four physalins subtypes (B, D, F, and G) have further studies. Therefore, we evaluated the crude ethanolic extract enriched with physalins B, D, F, and G from P. angulata leaves, a pool containing the physalins B, D, F, G, and the physalins individually, as P2X7 receptor antagonists. For this purpose, we evaluated ATP-induced dye uptake, macroscopic currents, and interleukin 1-ß (IL-1ß) in vitro. The crude extract and pool dose-dependently inhibited P2X7 receptor function. Thus, physalin B, D, F, and G individually evaluated for 5'-triphosphate (ATP)-induced dye uptake assay, whole-cell patch-clamp, and cytokine release showed distinct antagonist levels. Physalin D displayed higher potency and efficacy than physalin B, F, and G for all these parameters. In vivo mice model as ATP-induced paw edema was potently inhibited for physalin D, in contrast to physalin B, F, and G. ATP and lipopolysaccharide (LPS)-induced pleurisy in mice were reversed for physalin D treatment. Molecular modeling and computational simulation predicted the intermolecular interactions between the P2X7 receptor and physalin derivatives. In silico results indicated physalin D and F as a potent allosteric P2X7 receptor antagonist. These data confirm physalin D as a promisor source for developing a new P2X7 receptor antagonist with anti-inflammatory action.


Subject(s)
Acute Lung Injury/drug therapy , Physalis/chemistry , Plant Extracts/pharmacology , Secosteroids/pharmacology , Acute Lung Injury/physiopathology , Animals , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/isolation & purification , Anti-Inflammatory Agents/pharmacology , Computer Simulation , Disease Models, Animal , Dose-Response Relationship, Drug , HEK293 Cells , Humans , Male , Mice , Models, Molecular , Plant Extracts/administration & dosage , Plant Leaves , Purinergic P2X Receptor Antagonists/administration & dosage , Purinergic P2X Receptor Antagonists/isolation & purification , Purinergic P2X Receptor Antagonists/pharmacology , Receptors, Purinergic P2X7/drug effects , Secosteroids/isolation & purification
4.
J Phys Condens Matter ; 32(7): 075602, 2020 Feb 13.
Article in English | MEDLINE | ID: mdl-31671418

ABSTRACT

We develop a comparative study of the extended Hubbard model on three-site clusters of triangular and linear geometries, searching for geometrical-frustration effects on thermodynamic properties. Using exact diagonalization, we evaluate physical quantities such as specific heat, entropy, and spin correlations as functions of temperature, varying interaction parameters and electron density. In particular, we highlight the existence of clear signatures of frustration in the thermal behavior of the electronic specific heat in triangular clusters, which allows us to suggest that specific-heat measurements may be an important experimental tool to detect geometrical frustration in correlated-electron systems.

5.
Int J Oral Maxillofac Surg ; 48(11): 1485-1491, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31088706

ABSTRACT

This study was performed to evaluate the linear and volumetric effects of a technique for reconstruction of the posterior atrophic mandible, including the final bone gain of the graft, by three-dimensional assessment. Thirteen individuals were recruited into the study and submitted to a total of 15 mandibular autogenous bone block surgeries. Cone beam computed tomography images were obtained at three different times. Bone graft length and thickness, and the volume, height, and width of the graft were measured. Data were compared statistically among the time points using the Friedman test, and cluster analysis was performed to identify the association between the study variables and the resorption rate (α = 0.05). Linear analysis of the width and height of the recipient area at the different time points revealed a statistically significant difference. The final average increase in height was 1.6 mm; all subjects showed an average volume gain of 3.412mm3, and 77% of the subjects showed an average graft resorption of 0.688mm3 construction of three-dimensional vertical defects of the posterior mandible resulted in good healing with minimal complications and minimal bone graft resorption, favouring vertical bone gain.


Subject(s)
Alveolar Ridge Augmentation , Bone Resorption , Bone Transplantation , Cone-Beam Computed Tomography , Humans , Mandible
6.
J Helminthol ; 92(2): 244-249, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28349851

ABSTRACT

Cylindrospermopsis raciborskii (Woloszynska) is a photosynthetic cyanobacterium that can produce cytotoxic (cylindrospermopsin) and neurotoxic cyanotoxins (saxitoxins). In Brazil the strains of C. raciborskii are reported to produce only saxitoxins (STX) and their effect on fish parasites has not been tested to date. The fish Poecilia vivipara Bloch and Schneider is a common host for the trematode Pygidiopsis macrostomum Travassos off the coast of Rio de Janeiro, and this fish-parasite interaction is a model for behavioural and ecotoxicological studies. The aim of this work was to evaluate the motility of metacercariae of P. macrostomum from P. vivipara exposed to 40 mg l-1 and 400 mg l-1 of crude lyophilized extract of the cyanobacterium C. raciborskii (CYRF-01) for 48 h. The fish were separated into groups of ten individuals and, after exposure, five fish from each group were dissected for counting and checking the motility of metacercariae. The other five fish were dissected after 48 h in clean water. The detection and quantification of STX in the solutions of cyanobacteria, and the gills and guts of fish, were performed by an enzyme-linked immunosorbent assay. The crude extract of C. raciborskii caused temporary paralysis in metacercariae of P. macrostomum after exposure of fish to both concentrations, and the motility recovered after the fish were kept for 48 h in clean water. STX was detected in the guts and gills of all fish analysed, suggesting that this toxin is involved in the paralysis of metacercariae. This is the first report on the action of neurotoxins in metacercariae of fish.


Subject(s)
Cylindrospermopsis/chemistry , Metacercariae/drug effects , Saxitoxin/toxicity , Tissue Extracts/toxicity , Trematoda/drug effects , Trematode Infections/parasitology , Animals , Host-Parasite Interactions/drug effects , Movement/drug effects , Neurotoxins/pharmacology , Neurotoxins/toxicity , Poecilia/parasitology , Saxitoxin/pharmacology , Tissue Extracts/chemistry , Tissue Extracts/pharmacology , Trematoda/physiology
7.
Genet Mol Res ; 16(1)2017 Mar 22.
Article in English | MEDLINE | ID: mdl-28340263

ABSTRACT

Myrciaria dubia (camu-camu) is an Amazon tree that produces a tart fruit with high vitamin C content. It is probably the fruit with the highest vitamin C content among all Brazilian fruit crops and it can be used to supplement daily vitamin C dose. This property has attracted the attention of consumers and, consequently, encouraged fruit farmers to produce it. In order to identify and select potential accessions for commercial exploitation and breeding programs, M. dubia has received considerable research attention. The identification and characterization of genetic diversity, as well as identification of the population structure of accessions preserved in germplasm banks are fundamental for the success of any breeding program. The objective of this study was to evaluate the genetic variability of 10 M. dubia populations obtained from the shores of Reis Lake, located in the municipality of Caracaraí, Roraima, Brazil. Fourteen polymorphic inter simple sequence repeat (ISSR) markers were used to study the population genetic diversity, which resulted in 108 identified alleles. Among the 14 primers, GCV, UBC810, and UBC827 produced the highest number of alleles. The study illustrated the suitability and efficiency of ISSR markers to study the genetic diversity of M. dubia accessions. We also revealed the existence of high genetic variability among both accessions and populations that can be exploited in future breeding programs and conservation activities of this species.


Subject(s)
Myrtaceae/genetics , Trees/genetics , Alleles , Brazil , Fruit/chemistry , Fruit/genetics , Fruit/metabolism , Genetic Markers/genetics , Genetic Variation , Microsatellite Repeats , Myrtaceae/growth & development , Myrtaceae/metabolism , Phylogeny , Plant Breeding/methods , Polymorphism, Genetic , Trees/growth & development , Trees/metabolism , Vitamin A/biosynthesis
8.
J Helminthol ; 91(5): 605-612, 2017 Sep.
Article in English | MEDLINE | ID: mdl-27669886

ABSTRACT

Oncicola venezuelensis Marteau, 1977 was found parasitizing adults of Leopardus pardalis (Linnaeus) found dead in Serra da Capivara National Park, Piauí state, Brazil, a new geographical locality reported for the species. The diversity of Oncicola Travassos, 1916 species is large, but genetic data are scarce. This article presents the results of genetic, morphological and ultrastructural studies carried out for taxonomic purposes. The first ultrastructural view showed a globular, short proboscis with 36 hooks, divided into six longitudinal rows of six hooks each. Hooks differ in size and shape: hooks I, II and III have a 'chisel-shaped' tip. The genetic profile included new sequences of ribosomal DNA ITS1, 5.8S and ITS2, and partial 28S rRNA regions. The results of maximum-likelihood tree analyses for each region showed Oligacanthorhynchidae Southwell et Macfie, 1925 close to Gigantorhynchidae Hamann, 1892 (supported >91%). Both use mammals and birds as definitive hosts. Morphological and ultrastructural studies combined with genetic analysis shed more light on the diversity of Oncicola species.


Subject(s)
Acanthocephala/genetics , Acanthocephala/ultrastructure , Felidae/parasitology , Acanthocephala/classification , Acanthocephala/isolation & purification , Animals , Brazil , Cluster Analysis , DNA, Helminth/chemistry , DNA, Helminth/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Phylogeny , RNA, Ribosomal, 28S/genetics , RNA, Ribosomal, 5.8S/genetics , Sequence Analysis, DNA
9.
J Fish Dis ; 40(2): 191-203, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27260384

ABSTRACT

Pygidiopsis macrostomum and Ascocotyle (Phagicola) pindoramensis (Digenea: Heterophyidae) parasitize guppies as intermediate hosts and, respectively, fish-eating mammals or birds as definitive hosts. Heterophyids have zoonotic potential, and molecular studies associated with morphological and ecological aspects have helped to clarify their taxonomy and phylogeny. Poecilia vivipara naturally parasitized by metacercariae of both species (100% prevalence) exhibit no external signs of parasitism. In this work, four new sequences of P. macrostomum (18S rDNA, 28S rDNA and ITS2 rDNA) and one new sequence of A. (P.) pindoramensis (mtDNA cox-1) are presented. Phylogeny reconstructions linked P. macrostomum to other heterophyids, but the separation of the Heterophyidae and Opisthorchiidae remains unclear. Additionally, we used indirect immunocytochemistry and the phalloidin-fluorescence techniques allied with confocal laser scanning microscopy to describe muscular and neuronal structures of P. macrostomum. A complex arrangement of muscular fibres is associated with the tegument, suckers, gut and reproductive system. Radial fibres around the ventral sucker are thick, branched and extend to the body wall. High-resolution confocal imaging revealed a typical digenean muscular arrangement and important heterophyid morphological traits. These data will support future control measures to reduce the parasitism in guppies reared in fish farming systems, especially for aquarium and experimental purposes.


Subject(s)
DNA, Helminth/genetics , DNA, Ribosomal/genetics , Fish Diseases/epidemiology , Heterophyidae/physiology , Poecilia , Trematode Infections/veterinary , Animals , Brazil/epidemiology , Female , Fish Diseases/parasitology , Heterophyidae/anatomy & histology , Heterophyidae/genetics , Male , Microscopy, Confocal/veterinary , Phylogeny , Prevalence , Sequence Analysis, DNA/veterinary , Trematode Infections/epidemiology , Trematode Infections/parasitology
11.
Int J Oral Maxillofac Surg ; 43(6): 748-57, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24530034

ABSTRACT

The purpose of this systematic review was to evaluate clinical studies on the follow-up survival of implants inserted in the zygomatic bone for maxillary rehabilitation. A comprehensive search of studies published from 2000 to July 2012 and listed in the PubMed/MEDLINE, Embase, and Cochrane Library databases was performed in accordance with the PRISMA statement. Relevant studies were selected according to predetermined inclusion and exclusion criteria. The initial database search yielded 751 titles. After filtering, 313 abstracts were selected, culminating in 42 full text articles. Application of eligibility criteria led to the elimination of 17 articles. Hence 25 full-text articles were considered clinically relevant and were included. Calculations of the interval survival rates and cumulative survival rates of implants could be carried out on the data extracted from the final list of included studies for the different time intervals. These studies reported the insertion of a total of 1541 zygomatic implants and 33 implant failures. Failure generally occurred during the first year interval and was related to clinical complications, such as recurrent acute and chronic sinusitis. After a 36-month follow-up, the survival rate was 97.86%. Additional studies with longer follow-up periods, including the number of zygomatic implants inserted and details of the variations in the surgical techniques used and the impact of the maxillary morphology are still required.


Subject(s)
Dental Implantation, Endosseous/methods , Dental Implants , Dental Restoration Failure , Jaw, Edentulous/rehabilitation , Maxilla/surgery , Oral Surgical Procedures, Preprosthetic/methods , Zygoma/surgery , Dental Prosthesis, Implant-Supported , Humans , Treatment Outcome
12.
Acta Trop ; 127(1): 56-62, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23545127

ABSTRACT

Parasites with complex life cycles have the ability to change the behavior of their intermediate host in a way that increases their transmission rate to the next host. However, the level of behavioral changes can vary considerably, depending on the stage of parasite development and parasite intensity. To investigate the influence of such parameters, we evaluated the locomotory activity of the fish Poecilia vivipara prior to experimental infections, 7 days post-infection (dpi) and 14dpi with cercariae of the digenean Ascocotyle (Phagicola) pindoramensis. The locomotory activity was monitored using an image system, Videomex(®), linked to with a video camera able to record the swimming behavior of the fishes. At the end of the experiments, fishes were dissected and all metacercariae from the gills and mesenteries, the specific sites utilized by A. (P.) pindoramensis, were recovered and counted. There was a significant decrease in the swimming behavior of fishes after 14dpi. Similarly, we found a significant correlation between the swimming behavior of the fishes and parasite intensity in both sites of infection. It is surmised that the decrease in locomotory activity of P. vivipara caused by A. (P.) pindoramensis can disturb its predator-prey relationship in natural environment.


Subject(s)
Behavior, Animal , Fish Diseases/parasitology , Poecilia , Swimming , Trematode Infections/veterinary , Animals , Female , Fish Diseases/pathology , Male , Snails , Trematoda , Trematode Infections/parasitology , Trematode Infections/pathology , Video Recording
13.
J Appl Microbiol ; 114(4): 1158-65, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23279100

ABSTRACT

AIMS: To evaluate mannan oligosaccharide (MOS) and threonine effects on performance, small intestine morphology and Salmonella spp. counts in Salmonella Enteritidis-challenged birds. METHODS AND RESULTS: One-day-old chicks (1d) were distributed into five treatments: nonchallenged animals fed basal diet (RB-0), animals fed basal diet and infected with Salmonella Enteritidis (RB-I), animals fed high level of threonine and infected (HT-I), birds fed basal diet with MOS and infected (MOS-I), birds fed high level of threonine and MOS and infected (HT+MOS-I). Birds were inoculated at 2d with Salmonella Enteritidis, except RB-0 birds. Chicks fed higher dietary threonine and MOS showed performance similar to RB-0 and intestinal morphology recovery at 8 dpi. Salmonella counts and the number of Salmonella-positive animals were lower in HT+MOS-I compared with other challenged groups. CONCLUSION: Mannan oligosaccharides and threonine act synergistically, resulting in improved intestinal environment and recovery after Salmonella inoculation. SIGNIFICANCE AND IMPACT OF THE STUDY: Nutritional approaches may be useful to prevent Salmonella infection in the first week and putative carcass contamination at slaughter. This is the first report on the possible synergistic effect of mannan oligosaccharides and threonine, and further studies should be performed including performance, microbiota evaluation, composition of intestinal mucins and immune assessment.


Subject(s)
Animal Feed , Mannans/pharmacology , Salmonella Infections, Animal/prevention & control , Threonine/pharmacology , Animals , Cecum/microbiology , Diet/veterinary , Intestine, Small/anatomy & histology , Intestine, Small/drug effects , Male , Oligosaccharides/pharmacology , Salmonella enteritidis
14.
Int J Oral Maxillofac Surg ; 42(1): 113-9, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22776781

ABSTRACT

The aim of this study was to assess the improvement in psychosocial awareness of anophthalmic patients wearing ocular prostheses and its relationship with demographic characteristics, factors of loss/treatment, social activity, and relationship between professional and patient. Surveys including a form for evaluation of psychosocial pattern were conducted with 40 anophthalmic patients rehabilitated with ocular prosthesis at the Center of Oral Oncology in the authors' dental school from January 1998 to November 2010. The improvement in psychosocial awareness was assessed by comparing the perception of some feelings reported in the period of eye loss and currently. Wilcoxon tests were applied for comparison of patients' perception between the periods. χ(2) tests were used to assess the relationship between the improvement in psychosocial awareness and the variables of the study. In addition, the logistic regression model measured this relationship with the measure of odds ratio. The feelings of shame, shyness, preoccupation with hiding it, sadness, insecurity and fear were significant for improvement in psychosocial awareness. It was concluded that the anophthalmic patients wearing an ocular prosthesis has significant improvement in psychosocial awareness after rehabilitation.


Subject(s)
Anophthalmos/rehabilitation , Eye, Artificial/psychology , Adolescent , Adult , Aged , Aged, 80 and over , Anger , Anophthalmos/psychology , Attitude to Health , Child , Educational Status , Emotions , Employment/psychology , Eye Diseases/psychology , Eye Diseases/rehabilitation , Eye Injuries/psychology , Eye Injuries/rehabilitation , Fear , Female , Follow-Up Studies , Humans , Income , Interpersonal Relations , Male , Marital Status , Middle Aged , Professional-Patient Relations , Quality of Life , Self Concept , Shame , Shyness , Young Adult
15.
J Phys Condens Matter ; 24(25): 256005, 2012 Jun 27.
Article in English | MEDLINE | ID: mdl-22641091

ABSTRACT

We propose a three-dimensional model to describe magnetic interactions in a class of tantalite compounds of compositions A(x)A'(1-x)Ta(2)O(6), with A,A' = Fe, Co or Ni. Due to the quasi-two-dimensional nature of the magnetism in these compounds, experimental data have been previously interpreted using two-dimensional models. These are anisotropic Heisenberg models or Ising models and include competing exchange interactions from different neighbors. Taking into account all the relevant exchange terms, which include interplane interactions, we show that the latter allows us to understand the various low-temperature magnetic phases observed by neutron diffraction in this family of compounds. This is done by studying the eigenvalues of the exchange-interaction matrix in wavevector space for different sets of coupling parameters, of which those relative to in-plane interactions have been obtained from high-temperature series analysis of the magnetic susceptibility. This approach is rather general and the model presented here is directly applicable to isostructural compounds like ASb(2)O(6).

16.
Rio de Janeiro; INCA; 2011. ilus.
Non-conventional in Portuguese | BDENF - Nursing | ID: biblio-1037424

ABSTRACT

Acompanhamento, evolução e os diferentes tipos de coberturas/curativos utilizados em um paciente oriundo de outra Instituição hospitalar, portador de Leucemia Mieloide Aguda/ LMA com uma úlcera por pressão em região dorsal esquerda, após quimioterapia para a realização de Transplante de Células Tronco Hematopoiéticas / TCTH


Subject(s)
Male , Female , Humans , Nursing Care , Pressure Ulcer , Drug Therapy
17.
J Phys Condens Matter ; 22(21): 215701, 2010 Jun 02.
Article in English | MEDLINE | ID: mdl-21393724

ABSTRACT

Motivated by the superconducting properties of the metallic oxide Cd(2)Re(2)O(7), whose crystal structure is of the pyrochlore type, we propose an electronic model on a checkerboard lattice, which can be viewed as a two-dimensional analog of the pyrochlore lattice. Including only charge degrees of freedom, we treat the model via a Bardeen-Cooper-Schrieffer (BCS) approximation, decoupling the interaction terms in real space. Going over to reciprocal space yields a BCS model with two coupled bands. Characteristic properties such as order parameters and specific heat as functions of temperature are obtained. We also discuss the symmetry properties of the superconducting gap in wavevector space and the behavior of the critical temperature as a function of the electronic doping for various values of the interaction strength.

18.
J Phys Condens Matter ; 22(49): 496004, 2010 Dec 15.
Article in English | MEDLINE | ID: mdl-21406790

ABSTRACT

We report new results on the magnetic properties of the FexCo1 - xTa2O6 series of compounds. Essentially using neutron-diffraction and magnetic measurements we study, in more detail, the low-x limit of the temperature versus x phase diagram, where a new bicritical point is observed. The complete phase diagram shows three different magnetic phases at low temperature, for a high, intermediate and very low iron content. These phases consist of distinct antiferromagnetic orderings, characterized by different pairs of propagation vectors. We obtain information about the intraplane exchange interactions by fitting a high-temperature series of the magnetic susceptibility. Here we improve on a previously employed model, showing that two non-equivalent next-nearest-neighbor interactions must be taken into account in order to allow for in-plane magnetic orderings that are consistent with the neutron-diffraction results.

19.
Bioorg Med Chem Lett ; 10(8): 695-8, 2000 Apr 17.
Article in English | MEDLINE | ID: mdl-10782666

ABSTRACT

Synthesis and SAR of N-[4-[(4,5-dihydropyrazolo[3,4-d]thieno[3,2-b]azepin-6(2H)-y l)carbonyl]phenyl]benzamides as arginine vasopressin (AVP) receptor antagonists are discussed. Potent orally active AVP receptor antagonists are produced when the benzamide moiety contains a phenyl group at the 2-position. Similar analogues of 4,6,7,8-tetrahydro-5H-thieno[3,2-b]azepine and VPA-985 are reported.


Subject(s)
Arginine Vasopressin/antagonists & inhibitors , Azepines/chemical synthesis , Azepines/pharmacology , Animals , Arginine Vasopressin/metabolism , Azepines/chemistry , Azepines/metabolism , Rats , Receptors, Vasopressin/metabolism , Structure-Activity Relationship
20.
Mem. Inst. Oswaldo Cruz ; 94(5): 645-8, Sept. 1999. ilus
Article in English | LILACS | ID: lil-241325

ABSTRACT

A study was carried out using macrophages cultured from the peritoneal exudate of dogs infected in vitro with three species of Leishmania: L. (L.) chagasi, L. (Viannia) braziliensis and L. (L.) amazonensis with the aim of investigating the growth kinetics and infectivity of these species in the host cell. Results were expressed as the percentage of macrophages infected measured at 24 hr intervals over six days in RPMI - 1640 culture medium at a temperature of 34-35oC. The findings open the possibility of using canine peritoneal cells as a model for the screenning of leishmanicide drugs and to study the pathogenesis of these species.


Subject(s)
Animals , Dogs , Male , Female , In Vitro Techniques , Leishmania/pathogenicity , Macrophages, Peritoneal/parasitology , Leishmania braziliensis/pathogenicity , Leishmania infantum/pathogenicity , Leishmania mexicana/pathogenicity , Leishmaniasis, Cutaneous , Leishmaniasis, Mucocutaneous , Leishmaniasis, Visceral
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