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71.
Zusammenfassung In den Erythrozyten der beschriebenen Patientin, die klinisch an einer schweren hereditären nichtsphärozytären hämolytischen Anämie leidet, findet sich ein stark erhöhter Gehalt an den Adeninnukleotiden ADP und ATP. Versuche an substratfrei inkubierten intakten Erythrozyten zeigen eine verminderte Rate der ATP-Spaltung. Veränderungen der Aktivitäten von ATPasen oder Enzymen des Diphosphoglyzeratzyklus in Hämolysaten wurden dabei nicht gefunden. Da ein verminderter ATP-Abbau allein die Befunde nicht zu erklären vermag, wird gleichzeitig eine Störung in der Regulation der Nukleotidsynthese in den betroffenen Erythrozyten diskutiert. Erythrokinetische Untersuchungen mit51Cr ebenso wie mit DF32P ergaben einen Verlauf der Erythrozytenlebenszeitkurven, der auf eine zumindest quantitativ unterschiedliche Defektausprägung in zwei Erythrozytenpopulationen hinweist.Auch die Berechnung des absoluten ATP-Abfalles ergibt eine deutliche Verminderung in den pathologischen Zellen gegenüber der Norm. Er beträgt während der ersten 2 Stunden der Inkubation in den Patientenerythrozyten 0,83 nMol/ml Erythrozyten × min gegenüber 4,32 nMol in den Normalzellen. Berechnet man hieraus unter Berücksichtigung der jeweiligen Glykolyserate — näherungsweise — den absoluten ATP-Verbrauch der Zellen, so ergibt sich für die Patientenerythrozyten im Vergleich zu den Normalzellen eine Reduktion auf etwa 60%.Vortrag auf der 12. Tagung der Deutschen Gesellschaft für Hämatologie, Berlin, 17.–19. Oktober 1966. 相似文献
72.
Gastric perception thresholds are low and sensory neuropeptide levels high in helicobacter pylori-positive functional dyspepsia 总被引:7,自引:0,他引:7
Mönnikes H van der Voort IR Wollenberg B Heymann-Monnikes I Tebbe JJ Alt W Arnold R Klapp BF Wiedenmann B McGregor GP 《Digestion》2005,71(2):111-123
BACKGROUND AND AIMS: In functional dyspepsia (FD) decreased perception levels can be shown on gastric distension. Substance P (SP) and calcitonin gene-related peptide (CGRP) are involved in the sensitization of afferent neuronal pathways due to chronic inflammation. The role of Helicobacter pylori-induced gastric mucosal inflammation in the pathogenesis of FD is controversial. The aim of this study was to assess whether FD patients have altered mucosal concentrations of CGRP and SP, and to investigate whether this is associated with visceral hypersensitivity or H. pylori infection. METHODS: Gastrointestinal symptoms, H. pylori status, perception thresholds at gastric balloon distension, and gastric mucosal concentrations of CGRP and SP were determined in 13 FD patients and 18 healthy controls (HC). RESULTS: In H. pylori-positive FD patients discomfort and pain thresholds on gastric distension were lower compared to other groups. Antral mucosal levels of CGRP and SP were higher in H. pylori-positive subjects. In FD significantly negative correlations between discomfort and pain thresholds and antral mucosal concentrations of CGRP and SP were observed. CONCLUSIONS: In FD low perception thresholds on gastric distension are associated with high levels of CGRP and SP in the antrum, suggesting that sensory neuropeptides are involved in FD pathophysiology. 相似文献
73.
Busch MP; Laycock M; Kleinman SH; Wages JW Jr; Calabro M; Kaplan JE; Khabbaz RF; Hollingsworth CG 《Blood》1994,83(4):1143-1148
Blood donations in the United States have been screened for antibody to human T-lymphotropic virus type I (HTLV-I) by HTLV-I enzyme immunoassay (EIA) since November 1988. Specimens repeatedly found to be reactive by EIA undergo confirmation by supplementary serologic tests. We assessed the accuracy of blood center testing of 994 HTLV-I EIA repeat-reactive specimens in five US blood centers between November 1988 and December 1991. Of 410 confirmed HTLV-I/II donations, 407 (99.3%) were infected with HTLV-I/II, as determined by polymerase chain reaction (PCR) (403 cases) and by repeat serologic testing (4 cases). The three false- positive results occurred in the first year of testing. Of 425 HTLV- indeterminate specimens, 6 (1.4%) were found to be infected by PCR (5 with HTLV-II and 1 with HTLV-I). None of 159 confirmatory test-negative donations was PCR positive. Of HTLV-I/II-seropositive specimens, 80.2% to 95.4% could be typed as HTLV-I or HTLV-II by type-specific serologic assays. These results support recommendations that HTLV-I/II- seropositive donors should be advised that they are infected with HTLV- I, HTLV-II, or HTLV-I/II (depending on results of type-specific assays). HTLV-indeterminate donors should be advised that their results only rarely indicate HTLV infection. HTLV confirmatory test-negative donors should be reassured that they are not infected with HTLV-I or HTLV-II. 相似文献
74.
Reduction in CD8+ cell noncytotoxic anti-HIV activity in individuals receiving highly active antiretroviral therapy during primary infection 下载免费PDF全文
Stranford SA Ong JC Martinez-Marino B Busch M Hecht FM Kahn J Levy JA 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(2):597-602
Recent advances in the ability to detect people at the early stages of HIV infection now permit the initiation of antiretroviral treatment before the full complement of antiviral immune responses has evolved. However, the influence of early treatment interventions on the developing anti-HIV immune response is unknown. This study investigates the impact of standard highly active antiretroviral therapy (HAART) during the primary stages of HIV infection on the plasma HIV-1 RNA level, CD4(+) and CD8(+) lymphocyte counts, and the CD8(+) cell anti-HIV response. Individuals treated with HAART within 6 months of infection showed dramatic and rapid reductions in HIV-1 RNA levels along with modest increases in CD4(+) cell number and decreases in CD8(+) cell numbers. A significant reduction in the level of CD8(+) cell noncytotoxic suppression of HIV replication was observed over time in most participants receiving HAART. Importantly, those individuals choosing not to receive therapy maintained low but detectable HIV-1 RNA levels and showed no reduction in their CD8(+) cell antiviral response. These results suggest that either continued antigenic challenge is required to sustain CD8(+) cell-mediated anti-HIV activity, or that HAART has some inhibitory effect on this important immunologic function during the early stages of infection. 相似文献
75.
Jimme K Wiggers Bas Groot Koerkamp Zachri Ovadia Olivier R C Busch Dirk J Gouma Thomas M van Gulik 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(7):635-640
Objective
Routine extrahepatic bile duct (EBD) resection in non-jaundiced patients with gallbladder cancer (GBC) is controversial. The aim of this study was to retrospectively analyse patterns of recurrence in patients who underwent resection of GBC without routine EBD resection.Methods
This analysis referred to 58 patients who had undergone explorative laparotomy for GBC during 2000–2012 at a single, tertiary referral centre. Overall survival, time to recurrence, and patterns of recurrence were assessed in patients who underwent conventional negative-margin (R0) resection without routine EBD resection.Results
Of 58 patients submitted to explorative laparotomy for GBC, 26 (45%) patients underwent R0 resection without EBD resection (tumour stage T1b in five patients, T2 in 17, T3 in three, and T4 in one). The 3-year survival rate among these patients was 78% at a median follow-up of 33 months (range: 13–127 months). Seven patients developed recurrent disease at a median of 9 months (range: 2–25 months) after resection. No patients developed isolated recurrent disease at the EBD.Conclusions
Of 26 patients resected for GBC, none developed isolated recurrent disease at the EBD after conventional resection of GBC without EBD resection. This finding suggests that routine EBD resection is of no additional value. 相似文献76.
Björn L. Isfoss Christer Busch Helena Hermelin Anette T. Vermedal Marianne Kile Geir J. Braathen Bernard Majak Aasmund Berner 《Virchows Archiv : an international journal of pathology》2014,464(4):473-488
Survival after invasive bladder cancer has improved less than that of other common non-skin cancers. In many types of malignancy, treatment failure has been attributed to therapy-resistant stem-like cancer cells. Our aim was therefore to determine identities of stem cell marker-positive cells in bladder cancer tissue and to investigate possible associations between these cells and different forms of bladder neoplasia. We investigated tissue from 52 patients with bladder neoplasia and 18 patients with benign bladder conditions, from a cohort that had been previously described with regard to diagnosis and outcome. The samples were analysed immunohistologically for the stem cell markers aldehyde dehydrogenase 1 A1 (ALDH1) and CD44, and markers of cell differentiation. The majority of stem cell marker-positive cells were located in connective tissue, and a smaller fraction in epithelial tissue. Stem cell marker-positive cells exhibiting possible stem cell characteristics included cells in deeper locations of benign and malignant epithelium, and sub-endothelial cells in patients with or without neoplasia. Stem cell marker-positive cells with non-stem cell character included stellate cells, mast cells, endothelial cells, foamy histiocytes, and neurons. Significantly, ALDH1+ stellate cells and ALDH1+ mast cells were reduced in number in stroma of benign-appearing mucosa of bladder cancer patients. The stem cell markers ALDH1 and CD44 label several types of differentiated cells in bladder tissue. ALDH1+ stellate cells and mast cells appear to be reduced in stroma of normal-appearing mucosa of bladder cancer patients, and may be part of a “field effect” in cancer-near areas. 相似文献
77.
Florian Grahammer Nora Haenisch Frederic Steinhardt Lukas Sandner Malte Roerden Frederic Arnold Tomke Cordts Nicola Wanner Wilfried Reichardt Dontscho Kerjaschki Markus A. Ruegg Michael N. Hall Pierre Moulin Hauke Busch Melanie Boerries Gerd Walz Ferruh Artunc Tobias B. Huber 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(27):E2817-E2826
78.
Christine A. Conelea Andrew M. Busch Mark A. Catanzaro Cathy L. Budman 《Comprehensive psychiatry》2014
Objectives
Tourette Syndrome (TS) is a chronic neuropsychiatric condition that frequently persists into adulthood. Existing research has identified demographic and symptom-level variables associated with psychopathology and poor quality of life in TS. However, behavior patterns associated with enhanced or adaptive psychological and global functioning among adults with TS have yet to be empirically identified. The current study examined whether tic-specific activity restriction is related to emotional functioning and quality of life in adults with TS.Methods
Participants were 509 adults from the Tourette Syndrome Impact Survey who completed self-report measures of demographics, tic severity, emotional functioning, quality of life, and tic-related general and social activity restriction.Results
Partial correlations controlling for tic severity indicated that tic-related general and social activity restriction were significantly correlated with lower quality of life and poorer emotional functioning. Hierarchical linear regression models indicated that activity restriction significantly predicted lower quality of life and poorer emotional functioning when controlling for tic severity and demographic variables.Conclusions
Adults who restrict fewer activities due to tics, regardless of tic severity, experience greater quality of life and better emotional functioning. Clinically, adults with chronic tics may benefit from interventions focused on enhancing engagement in valued life activities. 相似文献79.
OG Pybus MA Suchard P Lemey FJ Bernardin A Rambaut FW Crawford RR Gray N Arinaminpathy SL Stramer MP Busch EL Delwart 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(37):15066-15071
We introduce a conceptual bridge between the previously unlinked fields of phylogenetics and mathematical spatial ecology, which enables the spatial parameters of an emerging epidemic to be directly estimated from sampled pathogen genome sequences. By using phylogenetic history to correct for spatial autocorrelation, we illustrate how a fundamental spatial variable, the diffusion coefficient, can be estimated using robust nonparametric statistics, and how heterogeneity in dispersal can be readily quantified. We apply this framework to the spread of the West Nile virus across North America, an important recent instance of spatial invasion by an emerging infectious disease. We demonstrate that the dispersal of West Nile virus is greater and far more variable than previously measured, such that its dissemination was critically determined by rare, long-range movements that are unlikely to be discerned during field observations. Our results indicate that, by ignoring this heterogeneity, previous models of the epidemic have substantially overestimated its basic reproductive number. More generally, our approach demonstrates that easily obtainable genetic data can be used to measure the spatial dynamics of natural populations that are otherwise difficult or costly to quantify. 相似文献
80.