Resumo Este trabalho tem como objetivo introduzir e discutir a metodologia de Shaw-Deser para descrever a interação entre matéria e radiação via simetria de calibre (abeliana/não abeliana). Nas entrelinhas, a mensagem que pretendemos passar é como a “impressão digital” da simetria de calibre local está contida na simetria de calibre global, por meio de uma interação corrente-campo (Dirac/Schwinger) e uma análise mais algébrica (iterativa), complementando a abordagem geométrica de Yang-Mills/Utiyama.

Abstract The aim of this work is to present and discuss the Shaw-Deser methodology to describe the interaction between matter and radiation by gauge symmetry (abelian/non-abelian). Between the lines, the message we intend to convey is how the “ fingerprint ” of local gauge symmetry is contained in global gauge symmetry, through a current-field interaction (Dirac/Schwinger) and a more algebraic (iterative) analysis, complementing the geometrical approach of Yang-Mills/Utiyama.

Resumo Este trabalho tem como objetivo discutir o comportamento de campos quânticos à temperatura finita. Primeiramente introduziremos os ingredientes relativísticos, quânticos e térmicos de maneira fenomenológica (Planck-Einstein) ao descrever o comportamento das partículas de radiação em equilíbrio com uma cavidade, o celebrado problema do corpo negro. Em seguida, mostraremos que a linguagem implícita do fenômeno físico em questão é uma linguagem de campos escalares não massivos de Klein-Gordon-Fock em (3+1) dimensões em equilíbrio térmico. Com este intuito, estudaremos o problema no formalismo de operadores e, a posteriori, no formalismo de integração funcional via matriz densidade de estados. Além disso, abordaremos o problema em diferentes representações (coordenadas/momento). A conexão entre uma teoria quântica no espaço de Minkowski e uma teoria quântica em equilíbrio no espaço Euclidiano por meio de uma rotação de Wick (tempo imaginário) será mostrada por meio das transformações de similaridade.

Abstract The aim of this work is to discuss the behavior of quantum fields at finite temperature. Initially, we will introduce phenomenologically the basic relativistic, quantum and thermal elements (Planck-Einstein), by describing the behavior of radiation in equilibrium with a cavity, the celebrated black body problem. Then, we will show that a proper language for describing this physical phenomena is the language of non-massive scalar fields (Klein-Gordon-Fock) in (3 + 1) dimensions, at thermal equilibrium. For this purpose, we will study the problem in the formalism of operators and a posteriori in the formalism of functional integration, by considering the density matrix of states. In addition, we will approach the problem in different representations (coordinates/momentum). The connection between a quantum theory in Minkowski space-time and a quantum theory in thermal equilibrium in Euclidean space by means of a Wick rotation (imaginary time) will be implemented by means of the appropriate similarity transformations.

Endometriosis is a benign, estrogen-dependent disease with symptoms such as pelvic pain and infertility, and it is characterized by the ectopic distribution of endometrial tissue. The expression of the ID2, PRELP and SMOC2 genes was compared between the endometrium of women without endometriosis in the proliferative phase of their menstrual cycle and the eutopic and ectopic endometrium of women with endometriosis in the proliferative phase. Paired tissue samples from 20 women were analyzed: 10 from endometrial and peritoneal endometriotic lesions and 10 from endometrial and ovarian endometriotic lesions. As controls, 16 endometrium samples were collected from women without endometriosis in the proliferative phase of menstrual cycle. Analysis was performed by real-time polymerase chain reaction (PCR). There was no significant difference between gene expression in the endometrium of women with and without endometriosis. The ID2 gene expression was increased in the most advanced stage of endometriosis and in ovarian endometriomas, the PRELP was more expressed in peritoneal lesions, and the SMOC2 was highly expressed in both peritoneal and endometrioma lesions. Considering that the genes studied participate either directly or indirectly in cellular processes that can lead to cell migration, angiogenesis, and inappropriate invasion, it is possible that the deregulation of these genes caused the development and maintenance of ectopic tissue.

The objective of this prospective study was to determine the plasma levels of nitric oxide (NO) in women with chronic pelvic pain secondary to endometriosis (n=24) and abdominal myofascial pain syndrome (n=16). NO levels were measured in plasma collected before and 1 month after treatment. Pretreatment NO levels (μM) were lower in healthy volunteers (47.0±12.7) than in women with myofascial pain (64.2±5.0, P=0.01) or endometriosis (99.5±12.9, P<0.0001). After treatment, plasma NO levels were reduced only in the endometriosis group (99.5±12.9 vs 61.6±5.9, P=0.002). A correlation between reduction of pain intensity and reduction of NO level was observed in the endometriosis group [correlation = 0.67 (95%CI = 0.35 to 0.85), P<0.0001]. Reduction of NO levels was associated with an increase of pain threshold in this group [correlation = -0.53 (-0.78 to -0.14), P<0.0001]. NO levels appeared elevated in women with chronic pelvic pain diagnosed as secondary to endometriosis, and were directly associated with reduction in pain intensity and increase in pain threshold after treatment. Further studies are needed to investigate the role of NO in the pathophysiology of pain in women with endometriosis and its eventual association with central sensitization.

The objective of the present study was to estimate the prevalence of chronic pelvic pain in the community of São Luís, capital of the State of Maranhão, Northeastern Brazil, and to identify independent conditions associated with it. A cross-sectional study was conducted, including a sample of 1470 women older than 14 years predominantly served by the public health system. The interviews were held in the subject's home by trained interviewers not affiliated with the public health services of the municipality. The homes were visited at random according to the city map and the prevalence of the condition was estimated. To identify the associated conditions, the significant variables (P=0.10) were selected and entered in a multivariate analysis model. Data are reported as odds ratio and 95% confidence interval, with the level of significance set at 0.05. The prevalence of chronic pelvic pain was 19.0%. The independent conditions associated with this diagnosis were: dyspareunia (OR=3.94), premenopausal status (OR=2.95), depressive symptoms (OR=2.33), dysmenorrhea (OR=1.77), smoking (OR=1.72), irregular menstrual flow (OR=1.62), and irritative bladder symptoms (OR=1.90). The prevalence of chronic pelvic pain in Sao Luís is high and is associated with the conditions cited above. Guidelines based on prevention and/or early identification of risk factors may reduce the prevalence of chronic pelvic pain in São Luís, Brazil.

The objective of this study was to determine the inter- and intra-examiner reliability of pain pressure threshold algometry at various points of the abdominal wall of healthy women. Twenty-one healthy women in menacme with a mean age of 28 ± 5.4 years (range: 19-39 years) were included. All volunteers had regular menstrual cycles (27-33 days) and were right-handed and, to the best of our knowledge, none were taking medications at the time of testing. Women with a diagnosis of depression, anxiety or other mood disturbances were excluded. Women with previous abdominal surgery, any pain condition or any evidence of inflammation, hypertension, smoking, alcoholism, or inflammatory disease were also excluded. Pain perception thresholds were assessed with a pressure algometer with digital traction and compression and a measuring capacity for 5 kg. All points were localized by palpation and marked with a felt-tipped pen and each individual was evaluated over a period of 2 days in two consecutive sessions, each session consisting of a set of 14 point measurements repeated twice by two examiners in random sequence. There was no statistically significant difference in the mean pain threshold obtained by the two examiners on 2 diferent days (examiner A: P = 1.00; examiner B: P = 0.75; Wilcoxon matched pairs test). There was excellent/good agreement between examiners for all days and all points. Our results have established baseline values to which future researchers will be able to refer. They show that pressure algometry is a reliable measure for pain perception in the abdominal wall of healthy women.