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OBJECTIVE: We describe the case of a patient who developed an episode of catatonia during the course of her life-long obsessive-compulsive disorder (OCD) and discuss issues related to the etiopathogenesis, differential diagnosis, and therapeutic management of this association. BACKGROUND: Catatonia is conventionally considered a heterogeneous syndrome of motor dysregulation characterized by mutism, immobility, negativism, posturing (catalepsy), stereotypies, and echophenomena. The relationship between OCD and catatonia is still misunderstood and poses significant challenges to the diagnosis and treatment of patients with both conditions. METHOD: Naturalistic follow-up of a single case. RESULTS: A patient with OCD developed catatonia in concert with deteriorating mood, thought, and behavior. This atypical clinical presentation of individuals with OCD and the list of differential diagnosis raised during the patient's clinical assessment are discussed on 3 different levels: symptomatic presentation, comorbidity pattern, and pharmacodynamic mechanisms involved. CONCLUSIONS: The development of a systematic therapeutic plan for patients with OCD and comorbid catatonia includes: the fine-tuning of the antiobsessional treatment; management of comorbid disorders that may engender catatonia; prompt discontinuation, and subsequent slow reintroduction of drugs deemed to trigger toxic reactions or to worsen comorbid disorders and, ultimately, the catatonia; and the implementation of specific anticatatonia measures.  相似文献   
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Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne's disease (JD), a chronic gastroenteritis of ruminants and other animals, including primates. Many evidences suggested association of MAP to Crohn's disease, a chronic granulomatous gastrointestinal disease of humans with strong similarities with JD. The present study attempts to evaluate global gene regulation in MAP, which has not been addressed previously, despite the availability of MAP genome sequence. For this purpose, we investigated: (i) the presence of sigma factors and their relationship to sigma factors of other mycobacteria (M. avium subsp.avium, M. tuberculosis, M. bovis, M. leprae and M. smegmatis), and (ii) their expression during different growth conditions and in vitro infection of intestinal epithelial Caco2 cells. MAP genome contains 19 putative sigma factor, but only 12 belong to gene families common to other mycobacteria. Gene expression was evaluated with Real-Time PCR during growth in 7H9 medium and mycobactin J, in 7H9 medium plus mycobactin J and lisozyme, and during infection of Caco2 cells: very different expression patterns were observed and, on the whole, only 7 sigma factors were found to be expressed. sigJ was upregulated during the infection of Caco2 cells. Even if only few sigma factors were expressed in the three conditions tested, the overall high numbers of MAP sigma factors suggests a noteworthy flexibility of this pathogen. Thus, this first report on expression of MAP sigma factors opens the way to an extensive characterization of global gene regulation, as a key to understand strategies of survival and mechanisms of infections used by this organism.  相似文献   
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In the course of a phase I trial, in which recombinant IL-2 (rIL-2) was infused intraperitoneally (i.p.) in patients with peritoneal carcinomatosis, we evaluated the effect on "tumor-associated lymphocytes" (TAL) isolated from the ascitic fluid. No major changes in the percentages of cells expressing the CD3, CD4, CD8, Leu-7, OKM1 and WT-31 antigens were detected either in TAL or in peripheral blood lymphocytes (PBL) after 7 days of rIL-2 infusion. In contrast the percentages of TAL (but not PBL) expressing surface IL-2 receptor (Tac), or LAK-1 antigen were sharply increased. Analysis of cytolytic functions showed a potentiation of the lytic activity against natural-killer (NK) sensitive K562 target cells and the de novo appearance of lytic activity against fresh melanoma cells. In one patient IFN-gamma was detected in the ascitic fluid following rIL-2 infusion. T-cell clones derived from the patient were analyzed for the IFN-gamma production. While only approximately 40% of PB-derived control clones produced medium to low amounts of IFN-gamma, all of the TAL-derived clones produced medium to high amounts of the lymphokine.  相似文献   
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A Western blot to detect anti-HSP70 autoantibodies has been reported to be of diagnostic value for immune-mediated hearing loss patients. While setting up this Western blot in our lab, we detected two main problems. First, some patients were positive for antibodies to a 70-kDa protein when tested against a whole cell lysate, but negative if the antigen used was purified HSP70. Second, if high amounts of purified HSP70 were loaded on the gel, both patients and healthy controls were positive. We have developed and optimized an ELISA as an alternative to the Western blot. This assay is more appropriate to identify positive and negative individuals because it is semi-quantitative. The ELISA is also more sensitive, requiring very low concentrations of the antigen and thus minimizing false positives. Finally, we demonstrated that immune-mediated hearing loss patients recognize mainly the native form of HSP70, a fact that potentially leads to false negatives when a denaturing Western blot assay is used for diagnosis. To test the diagnostic value of the ELISA, we performed a blind test with 70 hearing loss patients, as well as 30 healthy controls. A sensitivity of 84% and a specificity of 93% were obtained, superior to what has been reported so far for the Western blot.  相似文献   
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Mycobacterium tuberculosis, the etiological agent of tuberculosis, has lost many coding and noncoding regions in its genome during the course of evolution. We performed region-of-difference (RD) analysis using PCR-based genotyping of 131 M. tuberculosis clinical isolates obtained from four different countries, namely, India, Peru, Libya, and Angola. Our studies revealed that RD patterns are often distinct for strains circulating in specific geographical regions and can be used to trace the descent and spread of an isolate from its original reservoir. We describe our findings, which show that no single isolate from the four countries (n = 131) had all the 15 RDs either deleted or retained. Tuberculosis-specific deletion 1 (TbD1) was found to be conserved in 23% of the Indian isolates, indicating their possible ancient origin. RD9 was the most conserved region, RD11 was predominantly deleted, and RD6 was the most variable among the isolates in our collection irrespective of their geographic region. In contrast to earlier reports, our results demonstrate that the deletion of RD1 does not correlate with a decrease in the virulence potential of M. tuberculosis, as Indian isolates (n = 30) examined by us were from diseased individuals and yet had lost the RD1 region. Our results further illustrated that the intactness of the RD5 region may be associated with increased virulence of the organism. This study highlights that the RDs in M. tuberculosis genomes are geographically distributed and specific and may possibly be associated with virulence spectrum.  相似文献   
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The kinetic characteristics of muscle capillary blood flow (Qcap) during recovery from exercise are controversial (e.g. one versus two phases). Furthermore, it is not clear how the overall Qcap kinetics are temporally associated with muscle oxygen uptake (VO2m) kinetics. To address these issues, we examined the kinetics of Qcap estimated from the rearrangement of the Fick equation (Qcap=VO2m/C(a-v)O2) using the kinetics of pulmonary VO2 (VO2p, primary component) and deoxy-haemoglobin concentration ([HHb]) as indices of VO2m and C(a - v)O2 (arterio-venous oxygen difference) kinetics, respectively. VO2p (l min-1) was measured breath by breath and [HHb] (microm) was measured by near infrared spectroscopy during moderate (M; below lactate threshold, LT) and heavy exercise (H, above LT) in nine subjects. The kinetics of Qcap were biphasic, with an initial fast phase (tauI; M=9.3+/-4.9 s and H=6.0+/-3.8 s) followed by a slower phase 2 (tauP; M=29.9+/-8.6 s and H=47.7+/-26.0 s). For moderate exercise, the overall kinetics of Qcap (mean response time [MRT], 36.1+/-8.6 s) were significantly slower than the kinetics of VO2p (tauP; 27.8+/-5.3 s) and [HHb] (MRT for [HHb]; 16.2+/-6.3 s). However, for heavy exercise, there was no significant difference between MRT-[HHb] (34.7+/-10.4 s) and tauP for VO2p (32.3+/-6.7 s), while MRT for Qcap (48.7+/-21.8 s) was significantly slower than MRT for [HHb] and tauP for VO2p. In conclusion, during recovery from exercise the estimated Qcap kinetics were biphasic, showing an early rapid decrease in blood flow. In addition, the overall kinetics of Qcap were slower than the estimated VO2m kinetics.  相似文献   
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Over the last decade, we have witnessed an explosion of information regarding the function of glycoconjugates, carbohydrate-binding proteins, and the elucidation of the sugar code. This progress has yielded not only important insights into fundamental areas of glycobiology but has also influenced other fields such as immunology and molecular medicine. A family of galactoside-binding proteins, called galectins, has emerged recently as a novel kind of bioactive molecules with powerful, immunoregulatory functions. Different members of this family have been shown to modulate positively or negatively multiple steps of the inflammatory response, such as cell-matrix interactions, cell trafficking, cell survival, cell-growth regulation, chemotaxis, and proinflammatory cytokine secretion. To introduce a comprehensive overview of these new advances, here we will explore the molecular mechanisms and biochemical pathways involved in these functions. We will also examine the role of these proteins in the modulation of different pathological processes, such as chronic inflammation, autoimmunity, infection, allergic reactions, and tumor spreading. Understanding the intimate mechanisms involved in galectin functions will help to delineate selective and novel strategies for disease intervention and diagnosis.  相似文献   
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