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61.
This long-term follow-up study examined patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and only sensory
symptoms at first presentation, with emphasis on the development of motor symptoms and long-term disability. From all CIDP
patients referred to our Department between 1987 and 1995, seven had only sensory symptoms at first clinical presentation.
These were investigated according to a standard protocol, including a quantified clinical neurological examination and nerve
conduction studies. The mean duration of the disease before weakness developed was 3.1 years, but varied considerably (0.8–6.3
years). At follow-up, weakness developed in five patients and persisted in three of them. Five patients were not seriously
incapacitated by their disease (Rankin 1 or 2), four of them being in remission now and one showing a very slow progression
of disease. Two patients were moderately disabled (Rankin 3); one had severe persistent sensory ataxia and only weakness during
relapses and one had stepwise progression and moderate weakness. Motor nerve conduction studies revealed that the most notable
worsening in the entire group of patients was a decrease in distal compound muscle action potential amplitudes, indicating
the development of distal conduction block or axonal degeneration. These findings show that CIDP with only sensory symptoms
is a transient clinical stage that precedes the appearance of weakness in about 70% of patients. The long-term prognosis does
not differ from that of patients with CIDP who have weakness at the beginning of the disease.
Received: 3 December 1998 Received in revised form: 17 May 1999 Accepted: 2 July 1999 相似文献
62.
L-701,324, a selective antagonist at the glycine site of the NMDA receptor, counteracts haloperidol-induced muscle rigidity in rats 总被引:1,自引:1,他引:0
J. Konieczny Krystyna Ossowska Gert Schulze Helmut Coper Stanislaw Wolfarth 《Psychopharmacology》1999,143(3):235-243
Rationale: It has recently been suggested that the overactivity of glutamatergic neurotransmission may contribute to the pathophysiology
of Parkinson’s disease. Therefore, a search for new compounds which block glutamatergic receptors and show antiparkinsonian
properties in animal models of this disease seems to be justified. Objective: The aim of this study was to determine whether L-701,324 [7-chloro-4-hydroxy-3(3-phenoxy) phenylquinoline-2-(H)-one], a selective
and full antagonist at the glycine site of the NMDA receptor, counteracts parkinsonian-like muscle rigidity and catalepsy
induced by haloperidol in rats. Methods: The muscle tone was measured as the resistance developed to passive flexion and extension of the hind limb. Electromyographic
(EMG) activity was additionally recorded in the gastrocnemius and tibialis anterior muscles. Results: L-701,324 (2.5–40 mg/kg IP) dose-dependently decreased the muscle tone enhanced by haloperidol (1–5 mg/kg IP). Likewise, the
haloperidol-enhanced resting EMG activity and the EMG reflex response to passive movements were diminished by lower and almost
abolished by higher doses of L-701,324. However, up to a dose of 20 mg/kg IP, L-701,324 did not influence haloperidol (0.5
mg/kg IP)-induced catalepsy. Moreover, L-701,324 (1.25–5 mg/kg IP) given alone or together with haloperidol (0.5–1 mg/kg IP)
disturbed rotarod performance. Gross observation of behaviour indicated that rats injected with L-701,324 in doses equal to
or higher than 5 mg/kg, alone or in combination with haloperidol, were markedly ataxic, i.e. rats showed signs of disturbed
balance and loss of control over their hind limbs. Conclusions: The present study suggests that L-701,324 exhibits a beneficial action in the animal model of parkinsonian rigidity, but not
that of parkinsonian akinesia. Nonetheless, this compound is not devoid of motor side-effects.
Received: 1 February 1998 / Final version: 20 October 1998 相似文献
63.
Markus Haass Gert Richardt Albert Schömig 《Naunyn-Schmiedeberg's archives of pharmacology》1992,346(4):410-418
Summary The role of the cardiac energy status in the potassium-evoked exocytosis of both noradrenaline and the sympathetic co-transmitter neuropeptide Y (NPY) was investigated in the guinea-pig perfused heart. The transmitter release was stimulated by potassium depolarization (10–80 mmol/l) during normoxic perfusion (pO2 > 100 mmHg) in the presence of glucose (11 mmol/l) and at various periods (5–40 min) of cardiac energy depletion. Energy depletion was induced either by anoxia (pO2 < 5 mmHg) or by cyanide intoxication (1 mmol/l), both in combination with glucose-free perfusion. Endogenous noradrenaline and NPY were determined in the coronary venous overflow by high-pressure liquid chromatography combined with electrochemical detection and by radioimmunoassay, respectively.Under normoxic conditions potassium depolarization evoked a co-release of both transmitters [molar ratio 862 (noradrenaline) :1 (NPY)] at a threshold concentration of 40 mmol/l potassium. This transmitter overflow was characterized by its dependence on extracellular calcium and calcium influx through voltage-dependent neuronal calcium channels of the N-type. Cardiac energy depletion was accompanied by an acceleration and an enhancement of the potassium-evoked transmitter overflow. In comparison to normoxia, a 10-fold increased transmitter overflow with a comparable molar ratio [709 noradrenaline :1 (NPY)] was evoked by 40 mmol/l potassium after 10 min of either anoxia or cyanide intoxication. This sensitization to potassium depolarization reached a peak after 10 min of energy depletion and was characterized by a markedly reduced threshold concentration (10 mmol/l potassium). The enhanced sympathetic transmitter overflow in anoxia was suppressed by addition of glucose (11 mmol/l) to the perfusion buffer, suggesting that the sensitization of the overflow of noradrenaline and NPY to potassium depolarization requires a cessation of energy metabolism. The sensitization of the potassium-evoked (20 mmol/l) sympathetic transmitter overflow by energy depletion was further characterized: Consistent with an exocytotic release mechanism, the overflow was calcium-dependent. In contrast to normoxia, however, blockade of neuronal N-type calcium channels by either co-conotoxin (100 nmol/1) or cadmium chloride (50 mol/l) failed to reduce the potassium-evoked overflow of noradrenaline and NPY. In anoxia blockade of sodium-proton exchange by amiloride (1 mmol/l) or more specifically by ethylisopropylamiloride (1 mol/l) markedly attenuated the potassium-evoked transmitter overflow. Likewise, suppression of the potassium-evoked overflow of noradrenaline and NPY from the energy-depleted heart was achieved by extracellular acidosis (pH 6.0). In contrast, during normoxia blockade of sodium-proton exchange by either ethylisopropylamiloride (1 mol/l) or by extracellular acidosis (pH 6.0) did not affect the potassium-evoked (80 mmol/l) transmitter overflow. These findings suggest that the sensitization of sympathetic nerve endings to potassium depolarization, caused by cardiac energy depletion, requires sodium entry into the sympathetic nerve ending via sodium-proton exchange.The results of the present study indicate, that the threshold concentration for the potassium-evoked exocytotic release of noradrenaline and NPY from the guinea-pig isolated perfused heart is intimately coupled to the energy status of cardiac sympathetic nerve fibres. The energy status not only determines the quantity of the transmitters released but also the mode of sodium and calcium entry triggering the depolarization-evoked transmitter overflow.Preliminary findings were reported at the 63rd Scientific Sessions of the American Heart Association, Dallas/USA (Haass et al., 1990b) and at the Annual Meeting of the European Section of the International Society for Heart Research, Leuwen/Belgium (Haass et al. 1991b)Supported by a grant from the Deutsche Forschungsgemeinschaft (SFB 320 — Herzfunktion and ihre Regulation)
Correspondence to M. Haass at the above address 相似文献
64.
65.
Anja Ulmer Oleg Schmidt-Kittler J?rg Fischer Ulf Ellwanger Gernot Rassner Gert Riethmüller Gerhard Fierlbeck Christoph A Klein 《Clinical cancer research》2004,10(2):531-537
PURPOSE: The finding of melanoma cells in the peripheral blood, thus far mainly inferred from the PCR-based demonstration of tyrosinase mRNA, has been associated with metastatic melanoma. Neither the malignant nature nor the prognostic significance of circulating cells could be established. To address this question, we analyzed immunomagnetically isolated circulating melanoma cells for chromosomal aberrations and performed a clinical follow-up study of the enrolled patients. EXPERIMENTAL DESIGN: In a prospective study, blood samples were taken from 164 melanoma patients and 50 donors without malignant disease. Circulating melanoma cells were enriched by immunomagnetic cell sorting using a murine monoclonal antibody against the melanoma-associated chondroitin sulfate proteoglycan. To prove the malignant origin of the positive cells and to define their chromosomal aberrations, we analyzed the genomes of 15 individually isolated cells from seven patients by single-cell comparative genomic hybridization (SCOMP). RESULTS: Absolute and relative frequencies of circulating melanoma cells were associated with stage and with the presence or absence of detectable tumor. The detection of two or more cells correlated significantly with a reduced survival of patients with metastatic melanoma. All of the cells that were analyzed by SCOMP displayed multiple chromosomal changes and carried aberrations typical for melanoma. CONCLUSIONS: Immunomagnetic enrichment enables isolation and genomic characterization of circulating melanoma cells. The prognostic impact on survival of metastatic patients apparently reflects the aggressiveness of an ongoing tumor spread. Direct genomic analysis of the enriched and isolated cells will help to clarify the molecular-genetic basis of the establishment of generalized melanoma. 相似文献
66.
Tomas Norlander Sam-Hyun Kwon Gert Henriksson Karl Magnus Westrin Karin Sandstedt Pontus Stierna 《The Laryngoscope》1998,108(3):411-417
To investigate possible effects of corticosteroids on polyp formation and local bacterial colonization, pneumococcal sinusitis was experimentally induced in rabbits pretreated with betamethasone or saline. After 7 days, macroscopic polyps were counted post-mortem and on histologic slides after serial sectioning. Histologic sections were also examined with light microscopy. Macroscopic polyps were significantly fewer in animals given betamethasone, while there was no difference regarding the number of microscopic polyps. Ingrowth of pathogenic microorganisms was found in five of eight rabbits given placebo but in none of the animals treated with corticosteroids (P < 0.05). The reduced number of pathogenic strains in these animals may be explained by a better-preserved local host defense. The lower number of macroscopic polyps in the same animals could be because of a delayed mucosal repair and subsequent polyp formation. 相似文献
67.
Ilona Kryspin S rensen Eva Kristiansen Alicja Mortensen Gert M. Nicolaisen Jolanda A. H. Wijnands Henk J. van Kranen Coen F. van Kreijl 《Cancer letters》1998,130(1-2):217-225
Data from epidemiological studies suggest that isoflavones in soy may have a protective effect on the development of colon cancer in humans. Therefore, we have investigated whether soy isoflavones will inhibit intestinal tumour development in ApcMin mice. The mice were fed a Western-type high risk diet (high fat, low fibre and calcium) containing two different isolates of soy protein as a protein source. For the control and test groups this resulted in the administration of about 16 and 475 mg of total isoflavones per kg diet, respectively. As a positive control, a third group of mice was administered a low isoflavone diet supplemented with 300 ppm sulindac. No significant differences in the incidence, multiplicity, size and distribution of intestinal tumours were observed between Min mice fed low and high isoflavone-containing diets. However, a clear reduction in the number of small intestinal tumours was observed for the sulindac diet. Thus, in contrast to epidemiological studies, our results demonstrate that high amounts of soy isoflavones present in a Western-type high risk diet do not protect against intestinal tumour development in a relevant animal model such as the Min mice. 相似文献
68.
Anna van Rhenen Nicole Feller Angèle Kelder August H Westra Elwin Rombouts Sonja Zweegman Marjolein A van der Pol Quinten Waisfisz Gert J Ossenkoppele Gerrit Jan Schuurhuis 《Clinical cancer research》2005,11(18):6520-6527
PURPOSE: In CD34-positive acute myeloid leukemia (AML), the leukemia-initiating event originates from the CD34(+)CD38(-) stem cell compartment. Survival of these cells after chemotherapy may lead to minimal residual disease (MRD) and subsequently to relapse. Therefore, the prognostic impact of stem cell frequency in CD34-positive AML was investigated. EXPERIMENTAL DESIGN: First, the leukemogenic potential of unpurified CD34(+)CD38(-) cells, present among other cells, was investigated in vivo using nonobese diabetic/severe combined immunodeficient mice transplantation experiments. Second, we analyzed whether the CD34(+)CD38(-) compartment at diagnosis correlates with MRD frequency after chemotherapy and clinical outcome in 92 AML patients. RESULTS: In vivo data showed that engraftment of AML blasts in nonobese diabetic/severe combined immunodeficient mice directly correlated with stem cell frequency of the graft. In patients, a high percentage of CD34(+)CD38(-) stem cells at diagnosis significantly correlated with a high MRD frequency, especially after the third course of chemotherapy. Also, it directly correlated with poor survival. In contrast, total CD34(+) percentage showed no such correlations. CONCLUSIONS: Both in vivo data, as well as the correlation studies, show that AML stem cell frequency at diagnosis offers a new prognostic factor. From our data, it is tempting to hypothesize that a large CD34(+)CD38(-) population at diagnosis reflects a higher percentage of chemotherapy-resistant cells that will lead to the outgrowth of MRD, thereby affecting clinical outcome. Ultimately, future therapies should be directed toward malignant stem cells. 相似文献
69.
Tumor lymphangiogenesis in inflammatory breast carcinoma: a histomorphometric study. 总被引:11,自引:0,他引:11
Ilse Van der Auwera Gert G Van den Eynden Cecile G Colpaert Steven J Van Laere Peter van Dam Eric A Van Marck Luc Y Dirix Peter B Vermeulen 《Clinical cancer research》2005,11(21):7637-7642
PURPOSE: At the time of diagnosis, metastatic dissemination of tumor cells via the lymphatic system has occurred in nearly all patients with inflammatory breast cancer (IBC). The objective of this study was twofold: (a) to determine which is the most suitable marker of lymph vessels in primary breast tumors and (b) to compare histomorphometric lymph vessel variables in IBC and non-IBC. EXPERIMENTAL DESIGN: Serial sections of 10 IBCs and 10 non-IBCs were immunostained for D2-40, LYVE-1, podoplanin, and PROX-1. Relative lymph vessel area, lymph vessel perimeters, and counts and lymphatic endothelial cell proliferation (LECP) were then measured in D2-40/Ki-67 double-immunostained sections of 10 normal breast tissues, 29 IBCs, and 56 non-IBCs. RESULTS: D2-40 was the most suitable antibody for staining peritumoral and intratumoral lymph vessels. D2-40-stained intratumoral lymph vessels were present in 80% of non-IBCs and 82.8% of IBCs (P = 0.76). In non-IBC, lymph vessels located in the tumor parenchyma were smaller and less numerous than those at the tumor periphery (P < 0.0001) whereas in IBC, intratumoral and peritumoral variables were not significantly different. The mean relative tumor area occupied by lymph vessels was larger in IBC than in non-IBC (P = 0.01). LECP at the tumor periphery was higher in IBC than in non-IBC: median LECP was 5.74% in IBC versus 1.83% in non-IBC (P = 0.005). CONCLUSIONS: The high LECP in IBC suggests that lymphangiogenesis contributes to the extensive lymphatic spread of IBC. 相似文献
70.
It has been argued in previous issues of this journal that health technology assessment can be used as a tool to assess the efficiency of pharmaceutical care by linking its impact on clinical and humanistic outcomes to the resources required to achieve these outcomes. Additionally, as policy-makers appreciate the need to evaluate projects on the basis of their costs and benefits, the application of health technology assessment to pharmaceutical care may serve as a way of communicating with policy-makers and informing policy on pharmaceutical care.This article elaborates on this idea by arguing that policy-makers will be more likely to appreciate the value of pharmaceutical care if researchers pay more attention to some methodological principles underlying health technology assessment in the context of pharmaceutical care, and if they take into account the decision-making context facing policy-makers. In order to raise the methodological quality of studies, researchers need to take care to define better the pharmaceutical care intervention; to evaluate the costs of the intervention and its impact on the utilization of other health services; and to aggregate the various clinical and humanistic outcome measures that are commonly used in this type of research. In order to increase the usefulness of study findings to policy-makers, researchers need to identify the multiple objectives that policy-makers pursue, and show how study findings will aid policy-makers in attaining these objectives. 相似文献