77 resultados para behavioural phenotypes

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: The alpha1A-adrenergic receptor (alpha(1A)-AR) regulates the cardiac and peripheral vascular system through sympathetic activation. Due to its important role in the regulation of vascular tone and blood pressure, we aimed to investigate the association between the Arg347Cys polymorphism in the alpha(1A)-AR gene and blood pressure phenotypes, in a large sample of Brazilians from an urban population. Methods: A total of 1568 individuals were randomly selected from the general population of the Vitoria City metropolitan area. Genetic analysis of the Arg347Cys polymorphism was conducted by polymerase chain reaction/restriction fragment length polymorphism. We have compared cardiovascular risk variables and genotypes using ANOVA, and Chi-square test for univariate comparisons and logistic regression for multivariate comparisons. Results: Association analysis indicated a significant difference between genotype groups with respect to diastolic blood pressure (p = 0.04), but not systolic blood pressure (p = 0.12). In addition, presence of the Cys/Cys genotype was marginally associated with hypertension in our population (p = 0.06). Significant interaction effects were observed between the studied genetic variant, age and physical activity. Presence of the Cys/Cys genotype was associated with hypertension only in individuals with regular physical activity (odds ratio = 1.86; p = 0.03) or younger than 45 years (odds ratio = 1.27; p = 0.04). Conclusion: Physical activity and age may potentially play a role by disclosing the effects of the Cys allele on blood pressure. According to our data it is possible that the Arg347Cys polymorphism can be used as a biomarker to disease risk in a selected group of individuals.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Duchenne muscular dystrophy (DMD) is a human disease characterized by progressive and irreversible skeletal muscle degeneration caused by mutations in genes coding for important muscle proteins. Unfortunately, there is no efficient treatment for this disease; it causes progressive loss of motor and muscular ability until death. The canine model (golden retriever muscular dystrophy) is similar to DMD, showing similar clinical signs. Fifteen dogs were followed from birth and closely observed for clinical signs. Dogs had their disease status confirmed by polymerase chain reaction analysis and genotyping. Clinical observations of musculoskeletal, morphological, gastrointestinal, respiratory, cardiovascular, and renal features allowed us to identify three distinguishable phenotypes in dystrophic dogs: mild (grade I), moderate (grade II) and severe (grade III). These three groups showed no difference in dystrophic alterations of muscle morphology and creatine kinase levels. This information will be useful for therapeutic trials, because DMD also shows significant, inter- and intra-familiar clinical variability. Additionally, being aware of phenotypic differences in this animal model is essential for correct interpretation and understanding of results obtained in pre-clinical trials.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Cytoadherence of Plasmodium falciparum-infected red blood cells is mediated by var gene-encoded P. falciparum erythrocyte membrane protein-1 and host receptor preference depends in most cases on which of the 50-60 var genes per genome is expressed. Enrichment of phenotypically homogenous parasites by panning on receptor expressing cells is fundamental for the identification of the corresponding var transcript. Methods: P. falciparum 3D7 parasites were panned on several transfected CHO-cell lines and their var transcripts analysed by i) reverse transcription/PCR/cloning/sequencing using a universal DBL alpha specific oligonucleotide pair and ii) by reverse transcription followed by quantitative PCR using 57 different oligonucleotide pairs. Results: Each cytoadherence selected parasite line also adhered to untransfected CHO-745 cells and upregulation of the var gene PFD995/PFD1000c was consistently associated with cytoadherence to all but one CHO cell line. In addition, parasites panned on different CHO cell lines revealed candidate var genes which reproducibly associated to the respective cytoadherent phenotype. The transcription profile obtained by RT-PCR/cloning/sequencing differed significantly from that of RT-quantitative PCR. Conclusion: Transfected CHO cell lines are of limited use for the creation of monophenotypic cytoadherent parasite lines. Nevertheless, 3D7 parasites can be reproducibly selected for the transcription of different determined var genes without genetic manipulation. Most importantly, var transcription analysis by RT-PCR/cloning/sequencing may lead to erroneous interpretation of var transcription profiles.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Hemoglobinopathies were included in the Brazilian Neonatal Screening Program on June 6, 2001. Automated high-performance liquid chromatography (HPLC) was indicated as one of the diagnostic methods. The amount of information generated by these systems is immense, and the behavior of groups cannot always be observed in individual analyses. Three-dimensional (3-D) visualization techniques can be applied to extract this information, for extracting patterns, trends or relations from the results stored in databases. We applied the 3-D visualization tool to analyze patterns in the results of hemoglobinopathy based on neonatal diagnosis by HPLC. The laboratory results of 2520 newborn analyses carried out in 2001 and 2002 were used. The ""Fast"", ""F1"", ""F"" and ""A"" peaks, which were detected by the analytical system, were chosen as attributes for mapping. To establish a behavior pattern, the results were classified into groups according to hemoglobin phenotype: normal (N = 2169), variant (N = 73) and thalassemia (N = 279). 3-D visualization was made with the FastMap DB tool; there were two distribution patterns in the normal group, due to variation in the amplitude of the values obtained by HPLC for the F1 window. It allowed separation of the samples with normal Hb from those with alpha thalassemia, based on a significant difference (P < 0.05) between the mean values of the ""Fast"" and ""A"" peaks, demonstrating the need for better evaluation of chromatograms; this method could be used to help diagnose alpha thalassemia in newborns.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: The Rivermead Behavioural Memory Test (RBMT) assesses everyday memory by means of tasks which mimic daily challenges. The objective was to examine the validity of the Brazilian version of the RBMT to detect cognitive decline. Methods: 195 older adults were diagnosed as normal controls (NC) or with mild cognitive impairment (MCI) or Alzheimer`s disease (AD) by a multidisciplinary team, after participants completed clinical and neuropsychological protocols. Results: Cronbach`s alpha was high for the total sample for the RBMT profile (PS) and screening scores (SS) (PS=0.91, SS=0.87) and for the AD group (PS=0.84, SS=0.85), and moderate for the MCI (PS=0.62, SS=0.55)and NC (PS=0.62, SS=0.60) groups. RBMT total scores, Appointment, Pictures, Immediate and Delayed Story, Immediate and Delayed Route, Delayed Message and Date contributed to differentiate NC from MCI. ROC curve analyses indicated high accuracy to differentiate NC from AD patients, and, moderate accuracy to differentiate NC from MCI. Conclusions: The Brazilian version of the RBMT seems to be an appropriate instrument to identify memory decline in Brazilian older adults.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tick saliva contains molecules that are inoculated at the site of attachment on their hosts in order to modulate local immune responses and facilitate a successful blood meal. Bovines express heritable, contrasting phenotypes of infestations with the cattle tick, Rhipicephalus (Boophilus) microplus: breeds of Bos taurus indicus are significantly note resistant than those of Bos taurus taurus. Tick saliva may contain molecules that interfere with adhesion of leukocytes to endothelium and resistant hosts may mount an inflammatory profile that is more efficient to hamper the tick`s blood meal. We show in vitro that adhesion of peripheral blood mononuclear cells to monolayers of cytokine-activated bovine umbilical endothelial cells was significantly inhibited by tick saliva. The inflammatory response to bites of adults of R. microplus mounted by genetically resistant and susceptible bovine hosts managed in the same pasture was investigated in vivo. The inflammatory infiltrates and levels of message coding for adhesion molecules were measured in biopsies of tick-bitten and control skin taken when animals of both breeds were exposed to low and high tick infestations. Histological studies reveal that cutaneous reactions of resistant hosts to bites of adult ticks contained significantly more basophils and eosinophils compared with reactions of the susceptible breed. Expression of the adhesion molecules - intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and P-selectin - was higher in adult-infested skin of susceptible hosts undergoing low infestations compared to resistant hosts; when host was exposed to high infestations expression of these adhesion molecules was down-regulated in both phenotypes of infestations. Expression of leukocyte adhesion glycoprotein-1 (LFA-1) was higher in skin from susceptible hosts undergoing low or high infestations compared to resistant hosts. Conversely, higher levels of E-selectin, which promotes adhesion of memory T cells, were expressed in skin of resistant animals. This finding may explain the resistant host`s ability to mount more rapid and efficient secondary responses that limit hematophagy and infestations. The expression profiles observed for adhesion molecules indicate that there are differences in the kinetics of the inflammatory reactions mounted by resistant and susceptible hosts and the balance between tick and host is affected by the number of tick bites a host receives. We show that the contrasting phenotypes of infestations seen in bovines infested with R. microplus are correlated with differences in the cellular and molecular composition of inflammatory infiltrates elicited by bites with adult ticks. (C) 2009 Published by Elsevier B.V.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The alarm response to skin extract has been well documented in fish. In response to skin extract, there is a decline in both locomotion activity and aggressive interactions. Our observation herein of these responses in the cichlid Nile tilapia, Oreochromis niloticus, confirmed the existence of the alarm response in this species. However, so far there has been a paucity of information on the autonomic correlates of this response. In this study, the ventilatory change in response to the chemical alarm cue was evaluated. This parameter was measured 4 min before and 4 min after exposure to 1 mL of either conspecific skin extract or distilled water (extract vehicle). Skin extract induced an increase in the ventilation rate, which suggested an anticipatory adjustment to potentially harmful stimuli. The chemical cue (alarm substance) also interfered with the prioritisation of responses to different environmental stimuli (stimuli filtering); this was suggested by the observation that the Nile tilapia declined to fight after exposure to a cue that indicates a risk of predation. Furthermore, histological analysis of the Nile tilapia skin revealed the presence of putative alarm substance-producing (club) cells.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Hemoglobin profile studies have been carried out in four samples from different districts of Porto Velho (Rondonia State) in the western Amazonian region of Brazil: Candelaria, Bate Estaca, Hemeron (at the State Blood Bank), and Sao Carlos. Samples from 337 unrelated individuals were collected during medical and paramedical team visits by professionals from the Instituto de Pesquisa em Patologia Tropical and the Centro de Pesquisa em Patologias Tropicais (both research institutes in tropical diseases). The aim of this study is to assess the frequency of alleles in the hemoglobin system, mainly alleles HB*A, *S, and *E. The overall phenotype frequencies were FIB A,S = 0.025, HB A,E = 0.006, and HB A,A = 0.969. Samples from the blood bank subjects and samples from the homogeneous areas of Silo Carlos and Candelaria plus Bate Estaca have a chi-square of heterogeneity of 6.383 (p = 0.041) and 8.406 (p = 0.015), respectively. The allele frequencies (HB*A = 0.984, HB*S = 0.012, and HB*E = 0.003) do not significantly differ from frequencies found in other Brazilian regions.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Compound forms of Charcot-Marie-Tooth (CMT) disease have been recently associated with unusually severe neuropathies, an observation that prompted the proposition that the additive effects of two mutations should be searched in patients whose clinical severity falls outside the common CMT phenotypes. In this report, we present a father and a daughter with a very mild and unusual disease that segregates with two mutations in PMP22 gene, the 17p11.2-p12 duplication and a Ser72Leu point mutation. We propose that the deleterious effects of each mutation are partially compensated by the functional effect of the other.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The objective of this study was to investigate behavioural changes in Holstein heifers caused by exogenous adrenocorticotropic hormone (ACTH) administration. Twelve 11-month-old heifers were submitted to either a single saline or ACTH injection and then the treatments were switched after 3 days (n = 12 heifers/treatment). Heifers were in full view throughout the experimental period and recordings started immediately after ACTH and saline administration (injection corresponded to time 0 min), with general activity patterns of each heifer recorded on videotape for 24 h. Behavioural results during the first two experimental hours showed that heifers were less active and spent more time lying following ACTH than after saline treatment (P = 0.04). Also, heifers spent significantly less time ruminating immediately following ACTH injection (P = 0.05). However, feed intake measured after 4 and 24 h was similar between treatments (P > 0.05). Overall, there was no significant influence of ACTH treatment on frequency or duration of behaviours during the 4- and 24-h periods following injection (P > 0.05). The rapid and minimal effect of ACTH injection on behaviour suggests that peripheral administration of ACTH can be used to measure reactivity of the adrenal cortex without inducing biologically significant consequences. (C) 2010 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Here we report on the clinical and genetic data for a large sample of Brazilian patients studied at the Hospital de Reabilitacao de Anomalas Craniofaciais-Universidade de Sao Paulo (HRAC-USP) who presented with either the classic holoprosencephaly or the holoprosencephaly-like (HPE-L) phenotype. The sample included patients without detected mutations in some HPE determinant genes such as SHH, GLI2, SIX3, TGIF, and PTCH, as well as the photographic documentation of the previously reported patients in our Center. The HPE-L phenotype has been also called of HPE ``minor forms"" or ""microforms,"" The variable phenotype, the challenge of genetic counseling, and the similarities to patients with isolated cleft lip/palate are discussed. (c) 2010 Wiley-Liss, Inc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Collared Crescentchest (Melanopareia torquata) is endemic to the Cerrado Biome, and distributed mainly in Brazil, but extending to Bolivia and Paraguay. Although considered of least concern globally, it is threatened in the state of Sao Paulo in south-eastern Brazil. In this study we examined the morphology and some aspects of behaviour of the Collared Crescentchest. Birds were captured with mist-nets using playback in September-December 2006 and October-November 2007. For each captured bird, we took a range of morphological measurements, looked for brood-patches and moult, and took a blood sample for genetic determination of sex. Of the 35 individuals captured, only five were female, probably as a result of behavioural differences between sexes, with males apparently responding more readily to the playback. Furthermore, birds with white dorsal patches exhibited more aggression or risk taking behaviour than birds without patches. However, there was no sexual dimorphism in any of the morphological or colour traits measured ( although the female sample was small). Brood-patches were present mainly in October and November, but we did not detect any cloacal protuberance. Among the four species that comprise the family Melanopareiidae, this is the first record of brood-patches in males.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mobius sequence is a congenital facial and abducens nerve palsy, frequently associated to abnormalities of extremities. Arthrogryposis multiplex congenital is defined as a congenital fixation of multiple joints seldom of neurogenic origin. Both sequences must have a genetic origin, but usually are sporadic cases related to environmental factors such as drugs exposition and maternal trauma. A 5-year-old girl and a 1-year-old boy were born with Mobius sequence and arthrogryposis multiplex congenital, respectively. During pregnancies, the mother had vaginal bleeding at 7 weeks and used crack (free-based cocaine) in the first trimester, respectively. The girl also has equinovarus talipes and autistic behavior. The boy has arthrogryposis with flexion contractures of the feet and knees. A vascular disruption, due to hemorrhage and cocaine exposure, causing a transient ischemic insult to embryos in a critical period of development may be responsible for distinct phenotypes in these cases.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Many of the controversies around the concept of homology rest on the subjectivity inherent to primary homology propositions. Dynamic homology partially solves this problem, but there has been up to now scant application of it outside of the molecular domain. This is probably because morphological and behavioural characters are rich in properties, connections and qualities, so that there is less space for conflicting character delimitations. Here we present a new method for the direct optimization of behavioural data, a method that relies on the richness of this database to delimit the characters, and on dynamic procedures to establish character state identity. We use between-species congruence in the data matrix and topological stability to choose the best cladogram. We test the methodology using sequences of predatory behaviour in a group of spiders that evolved the highly modified predatory technique of spitting glue onto prey. The cladogram recovered is fully compatible with previous analyses in the literature, and thus the method seems consistent. Besides the advantage of enhanced objectivity in character proposition, the new procedure allows the use of complex, context-dependent behavioural characters in an evolutionary framework, an important step towards the practical integration of the evolutionary and ecological perspectives on diversity. (C) The Willi Hennig Society 2010.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

There is increasing evidence that spinal glial cells play an important role in chronic pain states. However, so far no data on the role of microglia in muscle pain are available. The aim of the present study was to investigate the involvement of spinal microglial cells in chronic muscle pain. In a rat model of chronic muscle inflammation (injection of complete Freunds adjuvant into the gastrocnemius-soleus muscle) alterations of microglia were visualized with quantitative OX-42 immunohistochemistry in the dorsal horn of the segments L4 and L5 12 days after induction of inflammation. In behavioural experiments the influence of chronic intrathecally applied minocycline - a specific microglia inhibitor - or an antibody against tumour necrosis factor-alpha (TNF-alpha: a cytokine released from microglia) on pain-related behaviour was investigated after 1, 3, 6, and 12 days. The immunhistochemical data show that in the deep laminae of the spinal dorsal horn microglial cells reacted with morphological changes to the muscle inflammation. Following inflammation, the mean boundary length surrounding the OX-42 immunostained area was significantly shorter. This indicates that microglial cells were activated by the myositis and withdrew their processes. Chronic intrathecal administration of minocycline or anti TNF-alpha with an osmotic mini-pump largely normalised the inflammation-induced changes in spontaneous exploratory behaviour and attenuated the hypersensitivity to mechanical stimulation. Both the immunohistochemical and behavioural data show that spinal microglial cells are involved in nociceptive processes in the cause of a chronic muscle inflammation. (C) 2008 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.