RESUMO
In this work, we tried to replicate and extend prior research on the relationship between social network size and the volume of the amygdala. We focused on the earliest evidence for this relationship (Bickart et al., Nature Neuroscience 14(2), 163-164, 2011) and another methodologically unique study that often is cited as a replication (Kanai et al., Proceedings of the Royal Society B: Biological Sciences, 279(1732), 1327-1334, 2012). Despite their tight link in the literature, we argue that Kanai et al. (Proceedings of the Royal Society B: Biological Sciences, 279(1732), 1327-1334, 2012) is not a replication of Bickart et al. Nature Neuroscience 14(2), 163-164 (2011), because it uses different morphometric measurements. We collected data from 128 participants on a 7-Tesla MRI and examined variations in gray matter volume (GMV) in the amygdala and its nuclei. We found inconclusive support for a correlation between measures of real-world social network and amygdala GMV, with small effect sizes and only anecdotal evidence for a positive relationship. We found support for the absence of a correlation between measures of online social network and amygdala GMV. We discuss different challenges faced in replication attempts for small effects, as initially reported in these two studies, and suggest that the results would be most helpful in the context of estimation and future meta-analytical efforts. Our findings underscore the value of a narrow approach in replication of brain-behavior relationships, one that is focused enough to investigate the specifics of what is measured. This approach can provide a complementary perspective to the more popular "thematic" alternative, in which conclusions are often broader but where conclusions may become disconnected from the evidence.
Assuntos
Tonsila do Cerebelo , Substância Cinzenta , Imageamento por Ressonância Magnética , Tonsila do Cerebelo/fisiologia , Tonsila do Cerebelo/diagnóstico por imagem , Humanos , Substância Cinzenta/fisiologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/anatomia & histologia , Masculino , Adulto , Feminino , Adulto Jovem , Rede Social , AdolescenteRESUMO
People vary in their general ability to compare, identify, and remember objects. Research using latent variable modeling identifies a domain-general visual recognition ability (called o) that reflects correlations among different visual tasks and categories. We measure associations between a psychometrically-sensitive measure of o and a neurometrically-sensitive measure of visual sensitivity to shape. We report evidence for distributed neural correlates of o using functional and anatomical regions-of-interest (ROIs) as well as whole brain analyses. Neural selectivity to shape is associated with o in several regions of the ventral pathway, as well as additional foci in parietal and premotor cortex. Multivariate analyses suggest the distributed effects in ventral cortex reflect a common mechanism. The network of brain areas where neural selectivity predicts o is similar to that evoked by the most informative features for object recognition in prior work, showing convergence of 2 different approaches on identifying areas that support the best object recognition performance. Because o predicts performance across many visual tasks for both novel and familiar objects, we propose that o could predict the magnitude of neural changes in task-relevant areas following experience with specific task and object category.
Assuntos
Reconhecimento Visual de Modelos , Córtex Visual , Humanos , Reconhecimento Visual de Modelos/fisiologia , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Encéfalo , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Vias Visuais/fisiologiaRESUMO
People with superior face recognition have relatively thin cortex in face-selective brain areas, whereas those with superior vehicle recognition have relatively thick cortex in the same areas. We suggest that these opposite correlations reflect distinct mechanisms influencing cortical thickness (CT) as abilities are acquired at different points in development. We explore a new prediction regarding the specificity of these effects through the depth of the cortex: that face recognition selectively and negatively correlates with thickness of the deepest laminar subdivision in face-selective areas. With ultrahigh resolution MRI at 7T, we estimated the thickness of three laminar subdivisions, which we term "MR layers," in the right fusiform face area (FFA) in 14 adult male humans. Face recognition was negatively associated with the thickness of deep MR layers, whereas vehicle recognition was positively related to the thickness of all layers. Regression model comparisons provided overwhelming support for a model specifying that the magnitude of the association between face recognition and CT differs across MR layers (deep vs. superficial/middle) whereas the magnitude of the association between vehicle recognition and CT is invariant across layers. The total CT of right FFA accounted for 69% of the variance in face recognition, and thickness of the deep layer alone accounted for 84% of this variance. Our findings demonstrate the functional validity of MR laminar estimates in FFA. Studying the structural basis of individual differences for multiple abilities in the same cortical area can reveal effects of distinct mechanisms that are not apparent when studying average variation or development.
Assuntos
Reconhecimento Facial , Adulto , Mapeamento Encefálico , Face , Humanos , Imageamento por Ressonância Magnética , Masculino , Reconhecimento Visual de Modelos , Lobo Temporal/diagnóstico por imagemRESUMO
The expertise hypothesis suggests the fusiform face area (FFA) is more responsive to faces than to other categories because of experience individuating faces. Accordingly, individual differences in FFA's selectivity for faces should relate to differences in behavioral face-recognition ability. However, previous studies have not demonstrated this, while the comparable association is often observed with nonface objects. We created a training paradigm with conditions sufficient to observe the same effect with faces. First, we selected subjects with a wide range of behavioral face-recognition abilities, then we manipulated experience with an artificial race of faces based on subjects' pretraining ability, maximizing variability in face individuation. Neural selectivity was measured for Caucasian faces and artificial-race faces relative to control objects. Selecting subjects for greater variability in face-recognition ability revealed an association between behavior and FFA selectivity for Caucasian faces, with an effect exclusive to the middle right FFA (FFA2). Manipulating experience with artificial-race faces led to stronger brain-behavior correlation for artificial-race faces, also in right FFA2. Group analyses showed an overlap of these effects for Caucasian and artificial-race faces in right FFA2. The right FFA2 appears particularly sensitive to experience with faces just as it is for nonface objects.
Assuntos
Reconhecimento Facial/fisiologia , Adolescente , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto JovemRESUMO
Just as people vary in their perceptual expertise with a given domain, they also vary in their abilities to imagine objects. Visual imagery and perception share common mechanisms. However, it is unclear whether domain-specific expertise is relevant to visual imagery. Although the vividness of visual imagery is typically measured as a domain-general construct, a component of this vividness may be domain-specific. For example, individuals who have gained perceptual expertise with a specific domain might experience clearer mental images within this domain. Here we investigated whether perceptual expertise for cars relates to visual imagery vividness in the same domain, by assessing the correlations between a widely used domain-general measure of visual imagery vividness (the Vividness of Visual Imagery Questionnaire; Marks in British Journal of Psychology, 64, 17-24, 1973), a new measure of visual imagery vividness specific to cars, and behavioral tests of car expertise. We found that domain-specific imagery relates most strongly to general imagery vividness and less strongly to self-reported expertise, while it does not relate to perceptual or semantic expertise.
Assuntos
Imaginação , Competência Profissional , Percepção Visual , Adulto , Feminino , Humanos , Masculino , Inquéritos e QuestionáriosRESUMO
The fusiform face area (FFA) is defined by its selectivity for faces. Several studies have shown that the response of FFA to nonface objects can predict behavioral performance for these objects. However, one possible account is that experts pay more attention to objects in their domain of expertise, driving signals up. Here, we show an effect of expertise with nonface objects in FFA that cannot be explained by differential attention to objects of expertise. We explore the relationship between cortical thickness of FFA and face and object recognition using the Cambridge Face Memory Test and Vanderbilt Expertise Test, respectively. We measured cortical thickness in functionally defined regions in a group of men who evidenced functional expertise effects for cars in FFA. Performance with faces and objects together accounted for approximately 40% of the variance in cortical thickness of several FFA patches. Whereas participants with a thicker FFA cortex performed better with vehicles, those with a thinner FFA cortex performed better with faces and living objects. The results point to a domain-general role of FFA in object perception and reveal an interesting double dissociation that does not contrast faces and objects but rather living and nonliving objects.
Assuntos
Córtex Cerebral/anatomia & histologia , Reconhecimento Visual de Modelos , Adolescente , Adulto , Face , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tamanho do Órgão , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Reconhecimento Psicológico/fisiologia , Adulto JovemRESUMO
Corticosteroid-binding globulin (CBG) is involved in the regulation of cortisol delivery. Neutrophil elastase-mediated cleavage of high to low affinity CBG (haCBG to laCBG) induces cortisol release at inflammatory sites. Past studies have shown reduced CBG in obesity, an inflammatory state, particularly in central adiposity/metabolic syndrome. We performed an observational, cross-sectional study of the effects of obesity, age and sex on ha/laCBG in 100 healthy volunteers. Total and haCBG levels were 11% higher in women but did not vary with age or menopausal status. Total CBG levels were lower with increased body weight and waist circumference; laCBG levels were lower with increased body weight, waist circumference, body mass index and body fat; higher haCBG levels were seen with increased body fat. The relation between CBG and adiposity appeared to be driven predominantly by the metabolic syndrome group. The results suggest reduced CBG cleavage in central obesity, possibly contributing to the characteristic inflammatory phenotype of the central obesity and metabolic syndrome. The mechanism of gender differences in CBG levels is unclear.
Assuntos
Síndrome Metabólica/metabolismo , Obesidade Abdominal/metabolismo , Transcortina/metabolismo , Adiposidade , Estudos de Coortes , Feminino , Voluntários Saudáveis , Humanos , Hidrocortisona/sangue , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Obesidade Abdominal/sangueRESUMO
Corticosteroid-binding globulin (CBG, transcortin) is the primary cortisol binding protein. It is a non-inhibitory serine protease inhibitor, capable of conformational change from a high cortisol-binding affinity form to a low affinity form upon cleavage of its reactive centre loop by various proteases, such as neutrophil elastase. The burgeoning inflammatory role of CBG applies to acute, severe inflammation where depletion is associated with mortality, and to chronic inflammation where defects in cortisol delivery may perpetuate inflammation. Naturally occurring human mutations influence a wide range of CBG properties and point toward a role in hitherto unexplained chronic musculoskeletal pain and fatigue disorders as well as potentially affecting fertility outcomes including offspring gender. In vitro and knock-out animal models of CBG propose a role for CBG in cortisol transport to the brain, providing a foundation for understanding the human observations in those with CBG mutations and sex differences in stress-related mood and behaviour. Finally, CBG measurement has a practical role in the estimation of free cortisol, useful in clinical circumstances where CBG levels or cortisol binding affinity is reduced. Taken together, novel data suggest a role for cortisol in targeted cortisol delivery, with implications in acute and chronic inflammation, as well as roles in metabolism and neurocognitive function, implying that CBG is a multifaceted component in the mechanisms of hypothalamic-pituitary-adrenal axis related homeostasis.
Assuntos
Transcortina/metabolismo , Animais , Doença/genética , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Humanos , Modelos Biológicos , Mutação/genética , Transcortina/química , Transcortina/genéticaRESUMO
How much do people differ in their abilities to recognize objects, and what is the source of these differences? To address the first question, psychologists have created visual learning tests including the Cambridge Face Memory Test (Duchaine & Nakayama, 2006) and the Vanderbilt Expertise Test (VET; McGugin et al., 2012). The second question requires consideration of the influences of both innate potential and experience, but experience is difficult to measure. One solution is to measure the products of experience beyond perceptual knowledge-specifically, nonvisual semantic knowledge. For instance, the relation between semantic and perceptual knowledge can help clarify the nature of object recognition deficits in brain-damaged patients (Barton, Hanif, & Ashraf, Brain, 132, 3456-3466, 2009). We present a reliable measure of nonperceptual knowledge in a format applicable across categories. The Semantic Vanderbilt Expertise Test (SVET) measures knowledge of relevant category-specific nomenclature. We present SVETs for eight categories: cars, planes, Transformers, dinosaurs, shoes, birds, leaves, and mushrooms. The SVET demonstrated good reliability and domain-specific validity. We found partial support for the idea that the only source of domain-specific shared variance between the VET and SVET is experience with a category. We also demonstrated the utility of the SVET-Bird in experts. The SVET can facilitate the study of individual differences in visual recognition.
Assuntos
Conhecimento , Psicolinguística , Semântica , Adulto , Idoso , Idoso de 80 Anos ou mais , Face , Feminino , Humanos , Individualidade , Internet , Masculino , Memória , Pessoa de Meia-Idade , Reconhecimento Psicológico , Reprodutibilidade dos Testes , Percepção Visual , Adulto JovemRESUMO
OBJECTIVE: Corticosteroid-binding globulin (CBG) is cleaved by neutrophil elastase converting the high-affinity (haCBG) conformation of CBG to a low-affinity (laCBG) conformation with a ninefold reduced cortisol-binding affinity. These in vitro data suggest that cortisol release by CBG cleavage results in the targeted delivery of cortisol to areas of inflammation. Our objective was to determine whether CBG cleavage alters circulating levels of haCBG and laCBG in vivo in proportion to sepsis severity. DESIGN: Prospective, observational cohort study in an adult tertiary level Intensive Care Unit in Adelaide, Australia. PATIENTS: Thirty-three patients with sepsis or septic shock grouped by illness severity [sepsis, septic shock survivors, septic shock nonsurvivors and other shock]. MEASUREMENTS: Plasma levels of haCBG and laCBG were assessed using a recently developed in-house assay in patients. Plasma total and free cortisol levels were also measured. RESULTS: Plasma total CBG and haCBG levels fell significantly, in proportion to disease severity (P < 0·0001 for both). There was a nonsignificant increase in free and total cortisol as illness severity worsened (P = 0·19 and P = 0·39, respectively). Illness severity was better correlated with haCBG levels than either free or total cortisol levels. CONCLUSIONS: Increasing illness severity in sepsis and septic shock is associated with markedly reduced circulating haCBG concentrations in vivo. We propose that low levels of haCBG in chronic inflammation may limit the availability of cortisol to inflammatory sites, perpetuating the inflammatory process.
Assuntos
Hidrocortisona/metabolismo , Inflamação/metabolismo , Sepse/metabolismo , Choque Séptico/metabolismo , Transcortina/metabolismo , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ligação Proteica , Sepse/sangue , Sepse/diagnóstico , Sepse/fisiopatologia , Índice de Gravidade de Doença , Choque Séptico/sangue , Choque Séptico/diagnóstico , Choque Séptico/fisiopatologia , Estatística como AssuntoRESUMO
The Vanderbilt Expertise Test for cars (VETcar) is a test of visual learning for contemporary car models. We used item response theory to assess the VETcar and in particular used differential item functioning (DIF) analysis to ask if the test functions the same way in laboratory versus online settings and for different groups based on age and gender. An exploratory factor analysis found evidence of multidimensionality in the VETcar, although a single dimension was deemed sufficient to capture the recognition ability measured by the test. We selected a unidimensional three-parameter logistic item response model to examine item characteristics and subject abilities. The VETcar had satisfactory internal consistency. A substantial number of items showed DIF at a medium effect size for test setting and for age group, whereas gender DIF was negligible. Because online subjects were on average older than those tested in the lab, we focused on the age groups to conduct a multigroup item response theory analysis. This revealed that most items on the test favored the younger group. DIF could be more the rule than the exception when measuring performance with familiar object categories, therefore posing a challenge for the measurement of either domain-general visual abilities or category-specific knowledge.
Assuntos
Automóveis , Aprendizagem/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Psicometria/métodos , Adulto JovemRESUMO
Some research finds that face recognition is largely independent from the recognition of other objects; a specialized and innate ability to recognize faces could therefore have little or nothing to do with our ability to recognize objects. We propose a new framework in which recognition performance for any category is the product of domain-general ability and category-specific experience. In Experiment 1, we show that the overlap between face and object recognition depends on experience with objects. In 256 subjects we measured face recognition, object recognition for eight categories, and self-reported experience with these categories. Experience predicted neither face recognition nor object recognition but moderated their relationship: Face recognition performance is increasingly similar to object recognition performance with increasing object experience. If a subject has a lot of experience with objects and is found to perform poorly, they also prove to have a low ability with faces. In a follow-up survey, we explored the dimensions of experience with objects that may have contributed to self-reported experience in Experiment 1. Different dimensions of experience appear to be more salient for different categories, with general self-reports of expertise reflecting judgments of verbal knowledge about a category more than judgments of visual performance. The complexity of experience and current limitations in its measurement support the importance of aggregating across multiple categories. Our findings imply that both face and object recognition are supported by a common, domain-general ability expressed through experience with a category and best measured when accounting for experience.
Assuntos
Face , Percepção de Forma/fisiologia , Reconhecimento Psicológico/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Perceptual expertise, even within the visual domain, can take many forms, depending on the goals of the practiced task and the visual information available to support performance. Given the same goals, expertise for different categories can recruit common perceptual resources, which could lead to interference during concurrent processing. We measured whether irrelevant characters of one writing system produce interference during visual search for characters of another writing system, as a function of expertise. Chinese-English bilinguals and English readers searched for target Roman letters among other distractors in a rapid serial visual presentation (RSVP) sequence. Chinese character distractors interfered with Roman letter search more than pseudoletter distractors, only for bilingual readers, suggesting a common perceptual bottleneck for Roman and Chinese processing in experts with both domains. We ruled out an explanation at the level of phonetic codes, by showing that concurrent verbal rehearsal has no effect on the magnitude of such interference. These findings converge with results showing competition between faces and cars in car experts to suggest that different domains of expertise that overlap in their cortical representations also possess a common perceptual bottleneck.
Assuntos
Discriminação Psicológica/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Redação , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Adulto JovemRESUMO
Neuroimaging provides a unique tool to investigate otherwise difficult-to-access mental processes like visual imagery. Prior studies support the idea that visual imagery is a top-down reinstatement of visual perception, and it is likely that this extends to object processing. Here we use functional MRI and multi-voxel pattern analysis to ask if mental imagery of cars engages the fusiform face area, similar to what is found during perception. We test only individuals who we assumed could imagine individual car models based on their above-average perceptual abilities with cars. Our results provide evidence that cars are represented differently from common objects in face-selective visual areas, at least in those with above-average car recognition ability. Moreover, pattern classifiers trained on data acquired during imagery can decode the neural response pattern acquired during perception, suggesting that the tested object categories are represented similarly during perception and visual imagery. The results suggest that, even at high-levels of visual processing, visual imagery mirrors perception to some extent, and that face-selective areas may in part support non-face object imagery.
Assuntos
Automóveis , Face , Adulto , Reconhecimento Facial , Humanos , MasculinoRESUMO
Parathyroid hormone-related protein (PTHrP) is a causative factor of humoral hypercalcemia in breast cancer and other malignancies. We studied circulating PTHrP levels with three different immunoassays directed against different parts of the PTHrP molecule in 48 patients with breast cancer and eucalcemia. The methods used were: (a) a RIA with antibodies directed toward the midregion (63-78); (b) an immunofluorometric assay with two antibodies against 1-34 and 38-67; and (c) an immunoradiometric assay with antibodies against 1-40 and 1-72. Although most patients had PTHrP levels indistinguishable from normal when measured by all three methods, four patients had increased serum levels in the IFMA. PTHrP was detected by immunohistochemistry in tumors from nearly all patients. One patient with elevated PTHrP in plasma measured by IFMA showed intense staining of tumor by immunohistochemistry; the tumor was histologically graded as III (severe) and was the largest of all tumors in this patient group. The IFMA can identify increased serum PTHrP in some patients with breast cancer who are not hypercalcemic. This assay may be especially useful in screening patients for this tumor during a relative early phase of the disease.
Assuntos
Neoplasias da Mama/química , Cálcio/sangue , Proteínas de Neoplasias/análise , Hormônio Paratireóideo/análise , Proteínas/análise , Adulto , Idoso , Neoplasias da Mama/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas de Neoplasias/sangue , Hormônio Paratireóideo/sangue , Proteína Relacionada ao Hormônio Paratireóideo , Proteínas/metabolismoRESUMO
Face recognition ability varies widely in the normal population and there is increasing interest in linking individual differences in perception to their neural correlates. Such brain-behavior correlations require that both the behavioral measures and the selective BOLD responses be reliable. The reliability of the location of the fusiform face area (FFA) has been demonstrated in several studies. Here, we address reliability of a different kind: reliability of the magnitude of responses to faces within this localized region. We calculated split-half reliability of face-selective responses within functionally defined posterior and anterior face-selective patches in the fusiform gyrus (FFA1/FFA2). We used data from two published studies that included both a functional localizer for face-selective regions and independent data suitable for quantifying face-selectivity. We found highly reliable face selectivity in both hemispheres that was highest in the centermost voxel(s) compared to larger regions of interest. Differences in face-selectivity between the two face patches within one hemisphere and across hemispheres were also reliable. Our results reveal considerable reliability of face-selective signals in and across FFA in adults. Given the good reliability of behavioral measures of face recognition, prior failures to find a relationship between the mean response to faces in FFA and behavioral face recognition in normal adult subjects are unlikely to be due to limitations of the measurements.
Assuntos
Reconhecimento Facial/fisiologia , Lobo Temporal/fisiologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Reprodutibilidade dos Testes , Lobo Temporal/diagnóstico por imagem , Adulto JovemRESUMO
BACKGROUND: While autism spectrum disorder (ASD) is characterized by both social communication deficits and restricted and repetitive patterns of behavior and interest, literature examining possible neural bases of the latter class of symptoms is limited. The fusiform face area (FFA) is a region in the ventral temporal cortex that not only shows preferential responsiveness to faces but also responds to non-face objects of visual expertise. Because restricted interests in ASD are accompanied by high levels of visual expertise, the objective of this study was to determine the extent to which this region responds to images related to restricted interests in individuals with ASD, compared to individuals without ASD who have a strong hobby or interest. METHODS: Children and adolescents with and without ASD with hobbies or interests that consumed a pre-determined minimum amount of time were identified, and the intensity, frequency, and degree of interference of these interests were quantified. Each participant underwent functional magnetic resonance imaging (fMRI) while viewing images related to their personal restricted interests (in the ASD group) or strong interest or hobby (in the comparison group). A generalized linear model was used to compare the intensity and spatial extent of fusiform gyrus response between groups, controlling for the appearance of faces in the stimuli. RESULTS: Images related to interests and expertise elicited response in FFA in both ASD and typically developing individuals, but this response was more robust in ASD. CONCLUSIONS: These findings add neurobiological support to behavioral observations that restricted interests are associated with enhanced visual expertise in ASD, above and beyond what would be expected for simply a strong interest. Further, the results suggest that brain regions associated with social functioning may not be inherently less responsive in ASD, but rather may be recruited by different environmental stimuli. This study contributes to our understanding of the neural basis of restricted interests in ASD and may provide clues toward developing novel interventions.
RESUMO
OBJECTIVE: High concentrations of parathyroid hormone-related protein (PTHrP) have been found in goat milk but it is not known whether it can enter the circulation of the neonate. In this study we have developed a sensitive two-site lanthanide immunofluorometric assay (IFMA) using dissociation and enhancement time-resolved fluorometry to address this question. METHOD: Affinity-purified anti-PTHrP 38-67 raised in rabbit was biotinylated and immobilized in streptavidin-coated microtitration wells as a 'capture' antibody. As a signal, affinity-purified anti-PTHrP 1-34, raised in sheep, was labeled with an europium chelate. A sensitivity of 0.3 pmol/l was achieved. PTHrP levels were determined in the plasma of eleven neonatal, seven parturient and six non-pregnant, non-lactating goats as well as in goat milk. RESULTS: The circulating PTHrP levels (mean +/- S.D.) were significantly increased at day 1 (6.1 +/- 1.7 pmol/l: P < 0.01) and day 3 (3.5 +/- 0.6 pmol/l: P < 0.05) after birth in the male kids (n = 8) bottle-fed with milk from the dams, compared with before (2.2 +/- 0.7 pmol/l) and 30 min after (2.0 +/- 0.6 pmol/l) the first feeding and 14 days (2.4 +/- 0.8 pmol/l) later. In the female kids (n = 3) fed with formula there was no such increase and the concentrations remained between 1.6-1.9 pmol/l. In the parturient goats the mean +/- S.D. PTHrP levels before, during and after parturition were 2.9 +/- 1.7, 4.2 +/- 2.4 and 3.7 +/- 2.2 pmol/l respectively (n = 7) which demonstrated that plasma PTHrP was higher during and after parturition in comparison with before (P < 0.05). The levels in non-pregnant, non-lactating goats were 3.3 +/- 1.5 pmol/l (n = 6). PTHrP levels in goat milk were in the nanomolar range and were highest in the colostrum. CONCLUSIONS: A significant increase of plasma PTHrP was observed in goat kids fed with milk from their dams and this increase was not found in kids fed with formula. Plasma PTHrP was also increased during parturition.
Assuntos
Animais Recém-Nascidos/sangue , Prenhez/sangue , Proteínas/análise , Envelhecimento/sangue , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Feminino , Fluorimunoensaio , Alimentos Formulados , Cabras , Trabalho de Parto/sangue , Masculino , Metais Terras Raras , Leite/química , Proteína Relacionada ao Hormônio Paratireóideo , Fragmentos de Peptídeos/análise , Gravidez , Coelhos , Sensibilidade e Especificidade , Fatores de TempoRESUMO
OBJECTIVES: To determine whether a very small focus of prostate cancer in a needle biopsy specimen correlates with organ-confined disease or with favorable disease parameters. METHODS: Of 598 needle biopsies of the prostate performed from January 1990 through June 1994, 49 specimens (8.2%) contained a microscopic focus (less than 2 mm in length of the entire biopsy core specimen) of adenocarcinoma. For these 49 patients, the clinical and pathologic features were correlated. RESULTS: Of these 49 patients, 27 (55.1%) underwent either radical prostatectomy, with or without pelvic lymph node dissection (26), or pelvic lymph node dissection alone (1). Seven of these 27 patients (25.9%) had extraprostatic disease: lymph node involvement (1), positive surgical margins (5), or seminal vesicle invasion (1). Ten of the 49 patients (20.4%) underwent radiotherapy, and 12 (24.5%) chose hormonal therapy. The pathologic stage for these 22 patients could not be ascertained. However, despite the limited amount of disease in the biopsy specimen, 2 patients treated with radiotherapy suffered a relapse (mean interval to recurrence, 11.5 months), and 3 patients treated with hormonal therapy (early or delayed) had bony metastasis at the time of diagnosis. Overall, 12 of the 49 patients (24.5%) had unfavorable disease (as defined by extraprostatic disease on pathologic specimen, relapse after radiotherapy, or bony metastasis at the time of diagnosis). CONCLUSIONS: These findings suggest that a microscopic focus of prostatic adenocarcinoma in a needle biopsy specimen, per se, does not predict the pathologic stage or the biologic behavior of a tumor.