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BACKGROUND: Young adults with early-onset major depressive disorder (MDD) may be at high risk of progression to bipolar disorder. Although hypomanic symptoms are common in young people with depression, many do not reach the strict DSM-IV and ICD-10 criteria for hypomania. We used an emerging innovative framework for bipolar spectrum to evaluate this question. METHODS: Consecutive referrals to a psychiatric outpatient clinic at a university health service were assessed for recurrent episodes of depression. DSM-IV diagnoses were based on a SCID-1 interview. We used two approaches to delineate bipolar spectrum. The first focused on bipolar spectrum disorder (BSD, as defined by Ghaemi et al. [Can. J. Psychiatry 47 (2002) 125]), and the second on a symptoms perspective based on MDD with a history of hypomanic symptoms, using a 15-point hypomanic symptoms checklist with a cut-off > or =8 or more symptoms (modified from J. Affect. Disord. 73 (2003) 39 and J. Affect. Disord. 73 (2003) 73). Data were also obtained on family history of affective disorder, course and number of episodes of depression, symptom severity, psychosocial functioning, suicidality and deliberate self-harm, and drug and alcohol use. RESULTS: High rates of bipolar and bipolar spectrum disorder were identified. Under DSM-IV, 14 subjects (16.1%) had bipolar affective disorder and 73 subjects (83.9%) had recurrent MDD. Depending on the method used to diagnose bipolar spectrum, between 47.1% and 77.0% of the total cohort could be so diagnosed. Hypomanic symptom counts, irrespective of duration, yielded the highest estimates for bipolar spectrum. High rates of pharmacological hypomania were also identified: 12 subjects (16.4%) with recurrent MDD group reported this, and all could be diagnosed with bipolar spectrum. LIMITATIONS: The reliability of using the 15-point hypomanic scale for the diagnostic assignments was not tested. All subjects were recruited from a university health service and, given the affluence of their parents, findings may not generalise to other populations. Most importantly, because bipolar family history and pharmacological hypomania were part of the diagnostic criteria of the BSD group, they could not be used as external validators for Ghaemi's BSD construct. CONCLUSIONS: Bipolar disorders emerge as extremely common in this cohort of young adults with recurrent depression. Antidepressant-induced hypomania and high scores on a hypomanic symptoms checklist help to identify patients who are likely to have a bipolar spectrum illness, but who do not meet DSM-IV criteria for bipolar disorder. This is a preliminary study, and further evidence from external validating strategies are needed to verify the bipolar status of these patients in a larger and unselected cohort representing a broader socio-economic demographic profile.  相似文献   
94.
Stromal-derived factor-1 (SDF-1/CXCL12) and its receptor CXCR4 play crucial roles in leukocyte migration and activation, as well as embryogenesis, angiogenesis, cancer and viral pathogenesis. CXCR4 is one of the major human immunodeficiency virus-1 (HIV-1) coreceptors on macrophages. In many tissues macrophages are one of the predominant cell types infected by HIV-1 and act as a reservoir for persistent infection and viral dissemination. In patients infected by HIV-1, blood and tissue levels of transforming growth factor-beta1 (TGF-beta1) are increased. The purpose of this study was to evaluate the effects of TGF-beta1 on CXCR4 expression and function in primary human monocyte-derived macrophages (MDMs) and rat microglia. TGF-beta1 up-regulated CXCR4 and enhanced SDF-1alpha-stimulated ERK1,2 phosphorylation in these cells. The increased CXCR4 expression in human MDMs resulted in increased susceptibility of the cells to entry by dual-tropic CXCR4-using HIV-1 (D-X4). In contrast, TGF-beta1 failed to increase CCR5 expression or infection by a CCR5-using virus in MDMs. Our data demonstrate that TGF-beta1 enhances macrophage responsiveness to SDF-1alpha stimulation and susceptibility to HIV-1 by selectively increasing expression of CXCR4. The results suggest that increased expression of CXCR4 on macrophages may contribute to the emergence of dual-tropic X4 viral variants at later stages of HIV-1 infection.  相似文献   
95.
Simultaneous turnover of normal and dysfunctional C1-inhibitor (C1-INH) was carried out in 10 normal subjects and 13 patients with rheumatoid arthritis as a measure of the in vivo activation of C1 and the contact activatable enzymes. In the first series of experiments, dysfunctional protein We was used in simultaneous turnover studies in five normal subjects and nine patients. The fractional catabolic rate of the dysfunctional C1-INH, We, (FCR(d)) was unchanged in both groups but the fractional catabolic rate of the normal C1-INH (FCR(n)) was faster in the patients compared to the controls, in particular patients with vasculitis. The enzyme-dependent catabolism defined as FCR(n-d) X concentration of C1-INH X plasma volume, was raised in the patient group, and correlated with disease activity score (r = 0.83, P less than 0.05). Neither FCR(n) nor FCR(d) was dependent on C1-INH concentration. The latter was higher in the patients (206 mg/l compared with 155 mg/l) indicating a very high synthetic rate in the patients (280.81 micrograms/kg/h compared with 179.77 micrograms/kg). In the second series of turnovers in six patients and five normal subjects, another dysfunctional C1-INH, at, was used. The FCR of C1-INH was slower than C1-INH (We) (1.88%/h compared with 2.7%/h). Enzyme-dependent catabolism of C1-INH in these patients were raised and also correlated with disease activity score (r = 0.82, P less than 0.05).  相似文献   
96.
Summary Dogs were inoculated with either an Ethiopian or Mexican rabies virus strain. The distribution of viral antigen and lesions were studied by immunofluorescence, histologic and electron microscopic techniques. In all dogs inoculated with the Ethiopian rabies virus strain, tremendous whorls of filamentous fluorescing aggregates were observed throughout the brain; these were not observed in dogs inoculated with the Mexican virus.Lesions consisted of neuronal degeneration and neuronophagia, associated with large inclusion bodies and widespread inflammation in dogs inoculated with the Ethiopian isolate. All observed portions of the brain and spinal cord were affected. In general, lesions were much less severe with the Mexican isolate. Occasional astrocytes were observed to have inclusions in dogs inoculated both with the Ethiopian and Mexican strains.Most neurons examined electronmicroscopically showed signs of infection, varying from a small granular or finely fibrillar viral matrix to numerous matrices accompanied by prolific numbers of virus particles occupying much of the perikaryon. These were found in all dogs inoculated with the Ethiopian strain but were rare with the Mexican isolate. Viral budding occurred from membranes of the rough endoplasmic reticulum, outer lamella of the nuclear envelope, and rarely from the plasma membrane.With 15 FiguresThis work was done while the senior author (Visiting Scientist) was being supported by the Swedish Aid for Research Cooperation with Developing Countries Project 77/89 A 9–49 U-forsk, through the Department of Bacteriology and Epizootology, Biomedicum, P.O. Box 583, S-75123 Uppsala, Sweden.  相似文献   
97.
A chordoma was examined by electron microscopy. It was composed of stellate and physaliphorous cells. The fine structure of these cells is described. Transitional type cells are also described and it is suggested that the physaliphorous cells develop from the stellate cells through a process of vacuolation. Two types of vacuoles are described, `smooth-walled' and `villous' endowed with numerous structureless microvilli. Some observations on stained sections are discussed.  相似文献   
98.
Vitamin B(12) levels in erythrocytes were low in untreated hypochromic anaemia, rose to abnormally high levels during therapy with iron alone, and finally slowly fell to normal. These changes were similar to those previously found in pernicious anaemia in response to vitamin B(12) therapy and in folate-deficiency anaemia in response to folic acid, thus changes in erythrocyte B(12) levels are not always due directly to changes in B(12) metabolism but may be secondary to changes in the levels of other haematinic factors.  相似文献   
99.
Tetanus toxoid has been used widely as an adjuvant. The atoxic fragment C from tetanus toxin (TetC) is potently immunogenic when expressed in Salmonella vaccine strains and has been used as a fusion partner for antigens (Ag). However, there has been no formal comparison of the immunomodulatory impact of TetC on its fusion partners. In this study, we have addressed this important issue. The protective 28-kDa glutathione S-transferase (GST) from Schistosoma haematobium (Sh28GST) was expressed either as a fusion to TetC or as the full-length Sh28GST alone in a nonvirulent aroA-attenuated strain of Salmonella enterica serovar Typhimurium. The Sh28GST proteins were soluble and stably expressed in Salmonella, as evaluated by Western blotting with TetC and/or Sh28GST antisera. Mice were immunized orally with a single dose of the live recombinant Salmonella. The constructs were stable in mice but, dramatically, only the strain expressing the TetC-Sh28GST fusion elicited significant antibody (Ab) responses directed against Sh28GST as determined by enzyme-linked immunosorbent assay. An analysis of the isotype profiles showed that these mice also produced anti-Sh28GST immunoglobulin A and GST-neutralizing assays revealed high levels of neutralizing Abs in sera. These are important correlates of protection in schistosomiasis. In addition, stimulation of spleen cells from immunized mice with Sh28GST Ag showed that both strains, expressing Sh28GST alone or the TetC-Sh28GST fusion, were able to stimulate the secretion of Th1-related cytokines (gamma interferon and interleukin 2) to comparable levels. Thus, TetC has modulated the immune responses generated against its fusion partner, Sh28GST, by markedly enhancing the Ab responses elicited. These results have important implications in the rational development of live vaccines.  相似文献   
100.
A previously described sequence-based epidemiological typing method for clinical and environmental isolates of Legionella pneumophila serogroup 1 was extended by the investigation of three additional gene targets and modification of one of the previous targets. Excellent typeability, reproducibility, and epidemiological concordance were determined for isolates belonging to both serogroup 1 and the other serogroups investigated. Gene fragments were amplified from genomic DNA, and PCR amplicons were sequenced by using forward and reverse primers. Consensus sequences are entered into an online database, which allows the assignment of individual allele numbers. The resulting sequence-based type or allelic profile comprises a string of the individual allele numbers separated by commas, e.g., 1,4,3,1,1,1, in a predetermined order, i.e., flaA, pilE, asd, mip, mompS, and proA. The index of discrimination (D) obtained with these six loci was calculated following analysis of a panel of 79 unrelated clinical isolates. A D value of > 0.94 was obtained, and this value appears to be sufficient for use in the epidemiological investigation of outbreaks caused by L. pneumophila. The D value rose to 0.98 when the results of the analysis were combined with those of monoclonal antibody subgrouping. Sequence-based typing of L. pneumophila is epidemiologically concordant and discriminatory, and the data are easily transportable. This consensus method will assist in the epidemiological investigation of L. pneumophila infections, especially travel-associated cases, by which it will allow a rapid comparison of isolates obtained in more than one country.  相似文献   
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