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1.
Braz. j. biol ; 82: 1-7, 2022. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468546

RESUMEN

The composition of macro endoparasites associated with the lizard Norops fuscoauratus (Squamata) was analysed in two localities in the Atlantic Forest on the northeast of Brazil between December 2012 and July 2015. 74 specimens of N. fuscoauratus were examined and five species of helminths were reported, being: (a) for the population of Pernambuco: Cystacanth (Prevalence=37.5%), Physaloptera retusa Rudolphi, 1819 (Prevalence=4.16%), larva of flatworm (Prevalence=2.08%), Rhabdias sp. (Prevalence=2.08%) and Strongyluris oscari Travassos, 1923 (Prevalence=2.08%), and (b) of Alagoas: S. oscari (Prevalence=17.85%) and Rhabdias sp. (Prevalence=3.57%). The differences in the composition of endoparasites in the two populations are attributed to individualities of environments occupied by the lizards. The collection period does not influence the abundance of parasites, but when associated with sex, there was a positive correlation with the abundance of helminths, with more females than males being infected with parasites in the rainy season.


A composição de macro endoparasitas associada com o lagarto Norops fuscoauratus (Squamata) foi analisada em duas localidades da Mata Atlântica no nordeste do Brasil, entre dezembro de 2012 e julho de 2015. 74 espécimes foram examinados e cinco espécies de helmintos foram encontradas, sendo: (a) para a população de Pernambuco: Cistacanto (Prevalência=37.5%), Physaloptera retusa Rudolphi, 1819 (Prevalência=4.16%), larva de platelminto (Prevalência=2.08%), Rhabdias sp. (Prevalência =2.08%) e Strongyluris oscari Travassos, 1923 (Prevalência =2.08%) e (b) Alagoas: S. oscari (Prevalência=17.85%) e Rhabdias sp. (Prevalência =3.57%). As diferenças na composição dos endoparasitas nas duas populações pode ser atribuída as individualidades dos ambientes ocupados por esses lagartos. O período de coleta não influenciou na abundância de parasitas, mas quando associado com o sexo, houve uma correlação positiva com a abundância de helmintos, com mais fêmeas do que machos, infectadas na estação chuvosa.


Asunto(s)
Animales , Helmintos , Lagartos/parasitología , Spiruroidea
2.
Braz. j. biol ; 822022.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468733

RESUMEN

Abstract The composition of macro endoparasites associated with the lizard Norops fuscoauratus (Squamata) was analysed in two localities in the Atlantic Forest on the northeast of Brazil between December 2012 and July 2015. 74 specimens of N. fuscoauratus were examined and five species of helminths were reported, being: (a) for the population of Pernambuco: Cystacanth (Prevalence=37.5%), Physaloptera retusa Rudolphi, 1819 (Prevalence=4.16%), larva of flatworm (Prevalence=2.08%), Rhabdias sp. (Prevalence=2.08%) and Strongyluris oscari Travassos, 1923 (Prevalence=2.08%), and (b) of Alagoas: S. oscari (Prevalence=17.85%) and Rhabdias sp. (Prevalence=3.57%). The differences in the composition of endoparasites in the two populations are attributed to individualities of environments occupied by the lizards. The collection period does not influence the abundance of parasites, but when associated with sex, there was a positive correlation with the abundance of helminths, with more females than males being infected with parasites in the rainy season.


Resumo A composição de macro endoparasitas associada com o lagarto Norops fuscoauratus (Squamata) foi analisada em duas localidades da Mata Atlântica no nordeste do Brasil, entre dezembro de 2012 e julho de 2015. 74 espécimes foram examinados e cinco espécies de helmintos foram encontradas, sendo: (a) para a população de Pernambuco: Cistacanto (Prevalência=37.5%), Physaloptera retusa Rudolphi, 1819 (Prevalência=4.16%), larva de platelminto (Prevalência=2.08%), Rhabdias sp. (Prevalência =2.08%) e Strongyluris oscari Travassos, 1923 (Prevalência =2.08%) e (b) Alagoas: S. oscari (Prevalência=17.85%) e Rhabdias sp. (Prevalência =3.57%). As diferenças na composição dos endoparasitas nas duas populações pode ser atribuída as individualidades dos ambientes ocupados por esses lagartos. O período de coleta não influenciou na abundância de parasitas, mas quando associado com o sexo, houve uma correlação positiva com a abundância de helmintos, com mais fêmeas do que machos, infectadas na estação chuvosa.

3.
Braz. j. biol ; 82: e241819, 2022. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1278484

RESUMEN

The composition of macro endoparasites associated with the lizard Norops fuscoauratus (Squamata) was analysed in two localities in the Atlantic Forest on the northeast of Brazil between December 2012 and July 2015. 74 specimens of N. fuscoauratus were examined and five species of helminths were reported, being: (a) for the population of Pernambuco: Cystacanth (Prevalence=37.5%), Physaloptera retusa Rudolphi, 1819 (Prevalence=4.16%), larva of flatworm (Prevalence=2.08%), Rhabdias sp. (Prevalence=2.08%) and Strongyluris oscari Travassos, 1923 (Prevalence=2.08%), and (b) of Alagoas: S. oscari (Prevalence=17.85%) and Rhabdias sp. (Prevalence=3.57%). The differences in the composition of endoparasites in the two populations are attributed to individualities of environments occupied by the lizards. The collection period does not influence the abundance of parasites, but when associated with sex, there was a positive correlation with the abundance of helminths, with more females than males being infected with parasites in the rainy season.


A composição de macro endoparasitas associada com o lagarto Norops fuscoauratus (Squamata) foi analisada em duas localidades da Mata Atlântica no nordeste do Brasil, entre dezembro de 2012 e julho de 2015. 74 espécimes foram examinados e cinco espécies de helmintos foram encontradas, sendo: (a) para a população de Pernambuco: Cistacanto (Prevalência=37.5%), Physaloptera retusa Rudolphi, 1819 (Prevalência=4.16%), larva de platelminto (Prevalência=2.08%), Rhabdias sp. (Prevalência =2.08%) e Strongyluris oscari Travassos, 1923 (Prevalência =2.08%) e (b) Alagoas: S. oscari (Prevalência=17.85%) e Rhabdias sp. (Prevalência =3.57%). As diferenças na composição dos endoparasitas nas duas populações pode ser atribuída as individualidades dos ambientes ocupados por esses lagartos. O período de coleta não influenciou na abundância de parasitas, mas quando associado com o sexo, houve uma correlação positiva com a abundância de helmintos, com mais fêmeas do que machos, infectadas na estação chuvosa.


Asunto(s)
Animales , Masculino , Femenino , Ascarídidos , Helmintos , Lagartos , Brasil , Bosques
4.
Braz J Biol ; 82: e241819, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34161426

RESUMEN

The composition of macro endoparasites associated with the lizard Norops fuscoauratus (Squamata) was analysed in two localities in the Atlantic Forest on the northeast of Brazil between December 2012 and July 2015. 74 specimens of N. fuscoauratus were examined and five species of helminths were reported, being: (a) for the population of Pernambuco: Cystacanth (Prevalence=37.5%), Physaloptera retusa Rudolphi, 1819 (Prevalence=4.16%), larva of flatworm (Prevalence=2.08%), Rhabdias sp. (Prevalence=2.08%) and Strongyluris oscari Travassos, 1923 (Prevalence=2.08%), and (b) of Alagoas: S. oscari (Prevalence=17.85%) and Rhabdias sp. (Prevalence=3.57%). The differences in the composition of endoparasites in the two populations are attributed to individualities of environments occupied by the lizards. The collection period does not influence the abundance of parasites, but when associated with sex, there was a positive correlation with the abundance of helminths, with more females than males being infected with parasites in the rainy season.


Asunto(s)
Ascarídidos , Helmintos , Lagartos , Animales , Brasil , Femenino , Bosques , Masculino
5.
Insect Mol Biol ; 27(5): 556-563, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29663605

RESUMEN

To investigate the effects of two nectar nonprotein amino acids, ß-alanine and γ-aminobutyric acid (GABA), on Osmia bicornis survival and locomotion, two groups of caged bees were fed with sugar syrup enriched with ß-alanine and GABA, respectively. A further control group was fed with sugar syrup. Five behavioural categories were chosen according to the principle of parsimony and intrinsic unitary consistency from start to end, and recorded by scan sampling: two states (remaining under paper or in tubes) and three events (walking on net, feeding from flower and flying). We also analysed the amino acid content of haemolymph sampled from an additional 45 bees fed the same diets (15 per diet type). Bees fed with ß-alanine had a significantly shorter survival time than those fed with the control and GABA diets. The GABA diet induced higher levels of locomotion than ß-alanine. The former nonprotein amino acid was only detected in the haemolymph of bees fed GABA. The results suggest that insects consuming nonprotein amino-acid-rich diets absorb and transfer these substances to the haemolymph and that nonprotein amino acids affect survival and locomotion. Ecological consequences are discussed in the framework of plant reproductive biology.


Asunto(s)
Abejas/fisiología , Locomoción , beta-Alanina/fisiología , Ácido gamma-Aminobutírico/fisiología , Animales , Femenino , Hemolinfa/metabolismo , Mortalidad
6.
J Vet Med ; 2017: 3102567, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28492060

RESUMEN

A Target Animal Safety protocol was used to examine adverse events in male and female Fischer F344/NTac rats treated with increasing doses of a subcutaneous implant of a lipid suspension of buprenorphine. A single injection of 0.65 mg/kg afforded clinically significant blood levels of drug for 3 days. Chemistry, hematology, coagulation, and urinalysis values with 2- to 10-fold excess doses of the drug-lipid suspension were within normal limits. Histopathology findings were unremarkable. The skin and underlying tissue surrounding the drug injection were unremarkable. Approximately 25% of a cohort of rats given the excess doses of 1.3, 3.9, and 6.5 mg/kg displayed nausea-related behavior consisting of intermittent and limited excess grooming and self-gnawing. These results confirm the safety of cholesterol-triglyceride carrier systems for subcutaneous drug delivery of buprenorphine in laboratory animals and further demonstrate the utility of lipid-based carriers as scaffolds for subcutaneous, long-acting drug therapy.

8.
Plant Biol (Stuttg) ; 17(3): 734-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25353653

RESUMEN

Pumpkin (Cucurbita pepo L.) pollen is starchy, sucrose-poor and recalcitrant, features opposite to those of several model species; therefore, some differences in carbohydrate metabolism could be expected in this species. By studying pumpkin recalcitrant pollen, the objective was to provide new biochemical evidence to improve understanding of how carbohydrate metabolism might be involved in pollen functioning in advanced stages. Four stages were analysed: immature pollen from 1 day before anthesis, mature pollen, mature pollen exposed to the environment for 7 h, and pollen rehydrated in a culture medium. Pollen viability, water and carbohydrate content and activity of enzymes involved in carbohydrate metabolism were quantified in each stage. Pollen viability and water content dropped quickly after dehiscence, as expected. The slight changes in carbohydrate concentration and enzyme activity during pollen maturation contrast with major changes recorded with ageing and rehydration. Pumpkin pollen seems highly active and closely related to its surrounding environment in all the stages analysed; the latter is particularly evident among insoluble sucrolytic enzymes, mainly wall-bound acid invertase, which would be the most relevant for sucrose cleavage. Each stage was characterised by a particular metabolic/enzymatic profile; some particular features, such as the minor changes during maturation, fast sucrolysis upon rehydration or sharp decrease in insoluble sucrolytic activity with ageing seem to be related to the lack of dormancy and recalcitrant nature of pumpkin pollen.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Cucurbita/metabolismo , Flores/fisiología , Polen/metabolismo , Cucurbita/fisiología , Ambiente , Sacarosa/metabolismo , beta-Fructofuranosidasa/metabolismo
9.
J Vet Med ; 2014: 365673, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26464927

RESUMEN

Subcutaneous drug implants are convenient systems for the long-term delivery of drugs in animals. Lipid carriers are logical tools because they generally allow for higher doses and low toxicity. The present study used an US Food and Drug Administration Target Animal Safety test system to evaluate the safety of a subcutaneous implant of a cholesterol-triglyceride-buprenorphine powder in 120 BALB/c mice. Mice were evaluated in 4- and 12-day trials with 1- and 5-fold doses of the intended 3 mg/kg dose of drug. One male mouse treated with three 3 mg/kg doses and surgery on days 0, 4, and 8 died on day 9. The cause of death was not determined. In the surviving 119 mice there was no evidence of skin reaction at the site of the implant. Compared to control animals treated with saline, weight measurements, clinical pathology, histopathology, and clinical observations were unremarkable. These results demonstrate that the lipid carrier is substantially safe. Cholesterol-triglyceride-drug powders may provide a valuable research tool for studies of analgesic and inflammatory drug implants in veterinary medicine.

10.
Panminerva Med ; 55(2): 217-24, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23676962

RESUMEN

AIM: The R577X polymorphism of the alpha-actinin-3 (ACTN3) gene and the IVS1-6G>A polymorphism of the ciliary neurotrophic factor (CNTF) gene have been associated with a favourable muscle phenotype (more muscle fibres with high glycolytic activity), reduced predisposition for congenital dystrophy and resistance to sarcopenia in old age. The aim of this study was to look for evidence of selective pressure towards genotypes favourable for strong muscle activity in a sample of national-level Italian athletes. METHODS: We analysed two stop codon polymorphisms in the DNA of 50 Italian athletes, specialised in power or endurance sports, and compared their genotypic distribution with those of a population of 50 controls. In a representative sub-group of athletes (N.=42) we then compared the genetic data with anaerobic threshold, assessed by an incremental exercise test up to exhaustion. RESULTS: The athlete group showed an allelic distribution of ACTN3 (R/R:64%, R/X:16%, X/X:20%) and CNTF (G/G:72%, G/A:26%, A/A:2%), significantly imbalanced towards alleles R/R and G/G, respectively, compared to controls (ACTN3=R/R:40% R/X:22% X/X:38% and CNTF=G/G:52%, G/A:24%, A/A:24%) (p=0.0024 and p=0.0001, respectively). Only the ACTN3 577X/X polymorphism showed a significant association with the anaerobic threshold of athletes (F-ratio= 4.037; p=0.025). Factorial ANOVA demonstrated a non significant interaction between favourable allelic patterns of ACTN3 and CNTF genes on aerobic performance in the athlete group. CONCLUSION: The relationship found between favourable muscle phenotype and this genetic profile may have interesting implications in sport performance and training, athlete selection and different clinical activities, such as physical rehabilitation and modifying phenotypes associated with neuromuscular diseases.


Asunto(s)
Actinina/genética , Atletas , Factor Neurotrófico Ciliar/genética , Músculo Esquelético/fisiología , Resistencia Física/genética , Polimorfismo Genético , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Prueba de Esfuerzo , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Italia , Masculino , Fuerza Muscular/genética , Consumo de Oxígeno/genética , Fenotipo
11.
Braz J Biol ; 72(4): 929-33, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23295524

RESUMEN

The parameters of infection by lung parasites from two sympatric lizards, Mabuya arajara and Anolis brasiliensis, from the Atlantic Rainforest of the lower slope of Chapada do Araripe in Northeastern Brazil were analyzed between September, 2009 and July, 2010. A total of 202 lizards were collected. 125 specimens were from Mabuya arajara and 77 from Anolis brasiliensis. M. arajara was infected by the pentastomid Raillietiella mottae while A. brasiliensis was infected by the nematode Rhabdias sp., with an overall prevalence of 1.6% and 28.6%, respectively. The mean intensity of infection by Rhabdias sp. was 3.63 ± 2.58 (range 1-15). The body size and sex of lizards did not influence the intensity of infection by Rhabdias sp. The overall prevalence was also not different between males and females hosts in A. brasiliensis. Both Anolis brasiliensis and Mabuya arajara represent a new host to Rhabdias sp. and Raillietiella mottae, respectively.


Asunto(s)
Lagartos/parasitología , Enfermedades Pulmonares Parasitarias/veterinaria , Enfermedades Parasitarias en Animales/epidemiología , Pentastomida , Infecciones por Rhabditida/veterinaria , Rhabditoidea/aislamiento & purificación , Animales , Brasil/epidemiología , Femenino , Lagartos/clasificación , Enfermedades Pulmonares Parasitarias/epidemiología , Enfermedades Pulmonares Parasitarias/parasitología , Masculino , Enfermedades Parasitarias en Animales/parasitología , Prevalencia , Infecciones por Rhabditida/epidemiología
12.
Proc Natl Acad Sci U S A ; 107(5): 1924-9, 2010 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-20080618

RESUMEN

Two-component signal transduction systems are widespread in prokaryotes and control numerous cellular processes. Extensive investigation of sensor kinase and response regulator proteins from many two-component systems has established conserved sequence, structural, and mechanistic features within each family. In contrast, the phosphatases which catalyze hydrolysis of the response regulator phosphoryl group to terminate signal transduction are poorly understood. Here we present structural and functional characterization of a representative of the CheC/CheX/FliY phosphatase family. The X-ray crystal structure of Borrelia burgdorferi CheX complexed with its CheY3 substrate and the phosphoryl analogue reveals a binding orientation between a response regulator and an auxiliary protein different from that shared by every previously characterized example. The surface of CheY3 containing the phosphoryl group interacts directly with a long helix of CheX which bears the conserved (E - X(2) - N) motif. Conserved CheX residues Glu96 and Asn99, separated by a single helical turn, insert into the CheY3 active site. Structural and functional data indicate that CheX Asn99 and CheY3 Thr81 orient a water molecule for hydrolytic attack. The catalytic residues of the CheX.CheY3 complex are virtually superimposable on those of the Escherichia coli CheZ phosphatase complexed with CheY, even though the active site helices of CheX and CheZ are oriented nearly perpendicular to one other. Thus, evolution has found two structural solutions to achieve the same catalytic mechanism through different helical spacing and side chain lengths of the conserved acid/amide residues in CheX and CheZ.


Asunto(s)
Fosfoproteínas/química , Fosfoproteínas/metabolismo , Monoéster Fosfórico Hidrolasas/química , Monoéster Fosfórico Hidrolasas/metabolismo , Secuencias de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Borrelia burgdorferi/enzimología , Borrelia burgdorferi/genética , Dominio Catalítico , Secuencia Conservada , Cristalografía por Rayos X , Evolución Molecular , Modelos Moleculares , Complejos Multiproteicos , Fosfoproteínas/genética , Monoéster Fosfórico Hidrolasas/genética , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Transducción de Señal , Especificidad por Sustrato
14.
Vox Sang ; 97(2): 147-52, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19392786

RESUMEN

BACKGROUND: Blood samples from patients with sickle cell disease (SCD) present to transfusion service with numerous antibodies, making the searching for compatible red blood cells (RBC) a challenge. To overcome this problem we developed an effective strategy to meet needs of supplying RBC-compatible units to SCD patients using DNA arrays. METHODS: We selected DNA samples from 144 SCD patients with multiple (receiving > 5 units) transfusions previously phenotyped for ABO, Rh(D, C, c, E, e), K1, Fy(a) and Jk(a). We also selected DNA samples from 948 Brazilian blood donors whose ABO/RhD phenotype matched that of the patients. All samples were analysed by DNA array analysis (HEA Beadchip(TM), Bioarray Solutions) to determine polymorphisms associated with antigen expression for 11 blood group systems (Rh, Kell, Kidd, Duffy, MNS, Dombrock, Lutheran, Landsteiner-Wiener, Diego, Colton, Scianna); and one mutation associated with haemoglobinopathies. RESULTS: Based on genotype results we were able to predict phenotype-compatible donors needed in order to provide compatible units to this group of patients. Based on their ABO/Rh phenotype we were able to find in this pool of donors compatible units for 134 SCD patients. CONCLUSION: Blood group genotyping by DNA array contributes to the management of transfusions in SCD patients by facilitating the transfusion support with antigen-matched blood. It has the potential to improve the life of thousands of SCD-transfused patients by reducing mortality due to transfusion reactions and immunization.


Asunto(s)
Anemia de Células Falciformes/terapia , Antígenos de Grupos Sanguíneos/genética , Transfusión Sanguínea/métodos , Eritrocitos/inmunología , Isoantígenos/genética , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Antígenos de Grupos Sanguíneos/análisis , Brasil , Estudios de Casos y Controles , Genotipo , Humanos , Inmunofenotipificación , Isoantígenos/sangre
15.
Childs Nerv Syst ; 25(1): 21-8, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18690465

RESUMEN

OBJECTS: Technical aspects of local chemotherapy in inoperable brainstem gliomas by convection-enhanced delivery (CED) are still under experimental considerations. In this study, we characterize the feasibility of multiple cannula placements in the rat brainstem. MATERIALS AND METHODS: In 38 male Fisher rats, up to three guided screws were positioned in burr holes paramedian at 2.5 mm anterior and posterior to as well as at the lambdoid suture. Using Alzettrade mark pumps (1 microl/h flow rate over 7 days) either vehicle (5% dextrose) or 0.1 mg carboplatin was delivered via one, two, or three cannulas, respectively. During cannula insertion, electrocardiogram and respiratory rate was monitored. All rats were subsequently evaluated neurologically for 8 days. For drug distribution in coronal sections, the brain tissue concentration of platinum was measured. HE staining was used to evaluate the local site of drug delivery. Heart and respiratory rate remained within normal range during surgical procedure. Neurological scoring showed only mild neurological impairment in the groups receiving two or three cannulas, which resolved after vehicle delivery. However, after carboplatin delivery, this deficit remained unchanged. Drug distribution was more homogeneous in the three cannula group. Histological slices visualized edematous changes at the sight of cannula placement. CONCLUSION: The unilateral application of up to three cannulas in the brainstem of rats for local drug delivery studies is feasible. The remaining neurological deficit in carboplatin-treated animals underlines the need of low toxicity drugs for CED in the brainstem.


Asunto(s)
Tronco Encefálico/diagnóstico por imagen , Carboplatino/administración & dosificación , Cateterismo/métodos , Sistemas de Liberación de Medicamentos/métodos , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Tronco Encefálico/lesiones , Carboplatino/efectos adversos , Cateterismo/efectos adversos , Electrocardiografía/métodos , Estudios de Factibilidad , Masculino , Microinyecciones , Examen Neurológico/métodos , Examen Neurológico/estadística & datos numéricos , Radiografía , Ratas , Ratas Endogámicas F344 , Técnicas Estereotáxicas/instrumentación
16.
J. venom. anim. toxins incl. trop. dis ; 15(4): 745-761, 2009. ilus
Artículo en Inglés | LILACS | ID: lil-532757

RESUMEN

The phospholipase A2 superfamily encompasses 15 groups that are classified into: secreted PLA2 (sPLA2); cytosolic PLA2 (cPLA2); Ca2+-independent intracellular PLA2 (iPLA2); platelet-activating factor acetylhydrolase (PAF-AH); and lysosomal PLA2. Currently, approximately 700 PLA2 sequences are known, of which 200 are obtained from the venom gland of Crotalinae snakes. However, thus far, little information is available on cloning, purification and structural characterization of PLA2 from Crotalus durisssus cascavela venom gland. In the present work, we report the molecular cloning of a novel svPLA2 from C. d. cascavella (Cdc), a predominant rattlesnake subspecies in northeastern Brazil. The Cdc svPLA2 cDNA precursor is 689 nucleotides long and encodes a protein of 138 amino acid residues, with a calculated molecular mass of approximately 13,847 Da and an estimated isoelectric point of 5.14. Phylogenetic analysis of Crotalinae PLA2 reveals that Cdc PLA2 clustered with other acidic type IIA PLA2 homologues is also present in the venom of North American rattlesnakes. Hitherto, this study presents a novel PLA2 cDNA precursor from C. d. cascavella and data reported herein will be useful for further steps in svPLA2 purification and analysis.


Asunto(s)
Animales , Masculino , Clonación Molecular , Venenos de Crotálidos
17.
Toxicon ; 52(8): 897-907, 2008 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-18926840

RESUMEN

Snake venom metalloproteases encompass a large family of toxins, with approximately 200 members already catalogued, which exhibit a diversity of structures and biological functions. From this relatively large number, only a dozen examples of apoptosis-inducing metalloproteases, like VAP1 and 2 from the venom of Crotalus atrox, are known. Since most VAP1-like toxins ever characterized were purified from the venom of Viperidae species inhabiting diverse places on earth, we investigate the expression of VAP-like metalloproteases in the venom gland of three representative pit vipers of the Brazilian territory. By molecular cloning and quantitative real-time polymerase chain reaction, using as calibrator gene the Crotalus durissus terrificus homolog of VAP1, named crotastatin, it is reported here that VAP1/crotastatin-like homologues in the venom gland of Bothrops atrox, C. d. cascavella and Lachesis m. rhombeata are expressed at different levels. Hence, batroxstatins, the crotastatin-like precursors from B. atrox, are expressed 87 times more than crotastatin-1, from C. d. cascavella, and 7.5-fold that lachestatins, from L. m. rhombeata. Moreover, in silico structural analysis of amino acid sequences indicates that batroxstatin-2, crotastatins and lachestatin-1 and -2 which share the archetypal motifs and metal- binding sites of VAP1, are subgrouped in a branch that comprises some apoptosis-inducing toxins.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/genética , Venenos de Crotálidos/genética , Crotalus/genética , Metaloendopeptidasas/genética , Secuencia de Aminoácidos , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Secuencia de Bases , Simulación por Computador , Venenos de Crotálidos/química , Venenos de Crotálidos/metabolismo , Crotalus/metabolismo , Expresión Génica , Biblioteca de Genes , Modelos Lineales , Metaloendopeptidasas/metabolismo , Metaloproteasas/genética , Metaloproteasas/metabolismo , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , ARN Mensajero/análisis , Alineación de Secuencia
18.
Protoplasma ; 228(1-3): 73-7, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16937057

RESUMEN

Pollen accumulates starch reserves during development and the final stage of ripening. Before the anther opens, starch is totally or partially converted to pectins, glucose, fructose, sucrose, and to some unknown polysaccharides. Pollen is exposed to dispersing agents in an arrested developmental state which differs according to pollen water content. Pollen is classified as partially dehydrated or partially hydrated. The final water content may be reached before or after anther opening. Especially during exposure and dispersal, partially dehydrated pollen may interconvert soluble and insoluble reserves, modifying internal turgor pressure and hindering water loss or gain. Partially hydrated pollen is commonly devoid of mechanisms to conserve viability in time but has the advantage of quickly emitting pollen tubes on reaching the stigma.


Asunto(s)
Carbohidratos/análisis , Polen/química , Polen/crecimiento & desarrollo , Agua/análisis , Supervivencia Celular , Desecación
20.
Int J Toxicol ; 24(6): 443-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16393937

RESUMEN

Ototoxicity is a common side effect of platinum-based chemotherapy. Intratumoral drug delivery theoretically could reduce the ototoxic effects of systemic drug infusions. However, local delivery to central nervous system (CNS) tumors might promote ototoxicity through drug release into cerebrospinal fluid (CSF). This report describes an examination of the cytoarchitecture of vestibular cells of cynomolgus monkeys that had chronic brainstem infusions with the maximum tolerated dose (MTD) of carboplatin. The brainstems of adult monkeys were infused for 30 days at 0.42 mu l/h with 0.025 to 0.25 mg/kg (MTD) of carboplatin. The vestibular sensory epithelia of eight drug-treated animals were isolated for microscopic examination of vestibular hair cells and support cells. Local infusions produced chronic elevated CSF levels of platinum, neurological symptoms, and radiographic evidence of pontine injury. Histology revealed significant cell damage at the infusion sites. Microscopic examinations of vestibular support cells and hair cells demonstrate a small reduction in cell counts in the drug-treated monkeys compared to a noninfused control animal. Parametric and nonparametric tests show no effect of dose in predicting the vestibular cell counts. In this single study of eight monkeys, a dose-dependent reduction of vestibular hair cells or support cells was not observed in animals infused with brainstem infusions of 0.025 to 0.25 mg/kg of carboplatin.


Asunto(s)
Antineoplásicos/toxicidad , Tronco Encefálico/efectos de los fármacos , Carboplatino/toxicidad , Animales , Antineoplásicos/administración & dosificación , Tronco Encefálico/diagnóstico por imagen , Tronco Encefálico/patología , Carboplatino/administración & dosificación , Carboplatino/farmacocinética , Recuento de Células , Células Ciliadas Vestibulares/efectos de los fármacos , Células Ciliadas Vestibulares/patología , Pérdida Auditiva/inducido químicamente , Pérdida Auditiva/patología , Bombas de Infusión , Macaca fascicularis , Masculino , Dosis Máxima Tolerada , Necrosis , Platino (Metal)/sangre , Platino (Metal)/líquido cefalorraquídeo , Radiografía , Canales Semicirculares/efectos de los fármacos , Canales Semicirculares/patología , Coloración y Etiquetado , Vestíbulo del Laberinto/efectos de los fármacos
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