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P Gajdos

Publications and source records attributed to P Gajdos.

At least 37 records · Page 2Linked to original sources

[Electrophysiologic study of 10 cases of Miller Fisher syndrome].

The association of ophthalmoplegia, ataxia and areflexia was described by Miller Fisher in 1956. It is postulated as a variant of the Guillain Barré syndrome. We report 10 Miller Fisher syndrome patients admitted in an intensive care unit between June 1990 and February 1999 who were selected according to clinical criteria of Ropper and Wijdicks. All patients had motor and sensory nerve conduction studies and electromyography, nine had visual and brainstem auditory evoked potentials and two had short latency somatosensory evoked potentials. Peripheral neuropathy was found in all patients. All had sensory nerve changes and some were severe. Motor nerve conduction abnormalities were observed in 7 only cases with moderate increase of F latency in 3 cases and compound muscle action potential reduction in 3 other cases. In the last case, motor conduction abnormalities was more severe, characterized by conduction velocity slowing in both distal and proximal sites and by temporal dispersion of action potentials. All brainstem auditory evoked studies were normal. In 4 patients, MRI studies were normal. These data support that brainstem is preserved in MFS. Only one patient had visual evoked potential abnormalities. Optic neuropathy is debated in Miller Fisher and in Guillain Barré syndrome. As a conclusion, in MFS peripheral neuropathy is always present with severe sensitive changes and moderate motor changes (This is different as compared to Guillain Barré syndrome according to electrophysiological data). We did not find involvement of brainstem in our patients with Miller Fisher syndrome.

Adolescent↗

[Respiratory disorders during sleep and myasthenia].

A sleep apnea syndrome is described by several studies in patients with myasthenia gravis. Apnea and hypopnea are mainly not obstructive and occur predominantly in rapid eye movement (REM) sleep. They are associated with oxygen desaturation. Although the sleep apnea index is not correlated with myasthenia gravis severity, it becomes less important as myasthenia gravis improves. Risk factors for the development of sleep apnea in myasthenia gravis patients are age, restrictive pulmonary syndrome, diaphragmatic weakness and daytime alveolar hypoventilation. Sleep apnea are not related to a central cholinergic effect in myasthenia gravis caused either by anticholinesterase used to treat myasthenia gravis or by antibodies to muscle acetylcholine receptors. Indeed acetylcholine receptors in brain are antigenically distinct from acetylcholine receptors in skeletal muscle. Sleep apneas are more likely caused by peripheral mechanisms. Correlation between sleep apnea and total lung capacity as well as the importance of diaphragmatic weakness in myasthenic patients may explain their predominance in REM sleep and their reduction with clinical improvement in the myasthenia gravis.

Diaphragm↗

[Detection of minimal residual disease in Ewing's sarcoma using RT-PCR].

BACKGROUND: More than 90% of Ewing's sarcomas (ES) contain a fusion of the EWS and FLI-1 genes, due to the t(11;22)(q23;q12) translocation. At the molecular level, the EWS-FLI-1 rearrangement shows great diversity. Specifically, many different combinations of exons from EWS-FLI-1 encode in-frame fusion transcripts and result in differences in length and composition of the chimeric protein, which function as an oncogenic aberrant transcription factor. The finding of this translocation gives evidence for the presence of ES cells. The aim of this prospective study was to verify applicability of the RT-PCR method for the detection of minimal residual disease in patients with ES. METHODS AND RESULTS: Conditions for the detection of Ewing's sarcoma cells by means of the reverse-transcriptase polymerase chain reaction (RT-PCR) at fusion transcripts in peripheral blood, bone marrow (BM) and autologous hematopoietic stem cell grafts in patients with ES were appointed. 31 samples of BM, 5 samples of blood and 7 peripheral blood grafts obtained from 23 patients were investigated. Presence of tumor cells was identified in 7 BM samples from 7 different patients (31 samples from 16 patients), all the peripheral blood and graft samples were negative. CONCLUSIONS: The high sensitivity of RT-PCR method in detection of cells bearing t(11;22)(q23;q12) was demonstrated in the experimental model and clinical samples. Likewise the literary statements, the RT-PCR method was found to be more sensitive than cytology.

Adolescent↗

[High-dose chemotherapy in the treatment of children with malignant lymphoma].

BACKGROUND: Children with primary refractory or recurrent malignant lymphoma have usually poor prognosis. Less than 10% of those, who were treated with conventional-dose regimens had survived for 2 years. In an attempt to improve the outcome for these patients, we explored the role of consolidation high-dose chemotherapy with autografting. METHODS AND RESULTS: Forty-five patients with poor-prognosis lymphoma, of whom 27 were males, underwent megatherapy between January 1992 and December 1999. High-dose chemotherapy was indicated in patients with poor initial response to first-line chemotherapy (14 cases) or in the relapse (31 cases). The group consisted of 27 patients with Hodgkin's disease and 18 patients with non-Hodgkin's lymphoma. The median age was 14.7 years. The conditioning for Hodgkin's disease patients contained cyclophosphamide, etoposide and busulfan or carmustine. Patients with non-Hodgkin's lymphomas received cyclophosphamide, etoposide and busulfan or total body irradiation. Bone marrow was used as the source of haemopoietic stem cells in ten patients, peripheral blood in twenty-eight, and both sources were used in seven patients. After the median follow-up of 47 months, the final survival was 61%. Eleven patients died of the disease progression, four of the infectious complications, one at a car accident. Median time to relapse after the transplantation was 7.5 months. CONCLUSIONS: Further improvement of these results will require earlier transplantation, improved preparative regiments or early posttransplant immunotherapy.

Adolescent↗

Compartmentalised inducible nitric-oxide synthase activity in septic shock.

BACKGROUND: Previous experimental studies support a role for inducible nitric-oxide synthase (iNOS) in the pathogenesis of severe sepsis. The aim of the study was to characterise iNOS activity in different tissues in patients with septic shock. METHODS: 13 consecutive patients with septic shock caused by cellulitis were enrolled. Skin, muscle, fat, and artery samples were obtained from normal, inflamed, and putrescent areas to measure iNOS activity, and concentrations of tumour necrosis factor alpha (TNFalpha) and interleukin 1beta (IL-1beta). In two patients, iNOS activity was also assessed in peripheral blood mononuclear cells (PBMC) incubated with microorganisms causing the sepsis, or in macrophages isolated from suppurating peritoneal fluid incubated with IL-1beta. FINDINGS: Compared with normal and inflamed areas, iNOS activity was increased in putrescent areas for muscle (71-fold [95% CI 20-259] vs normal areas, 69-fold [19-246] vs inflamed areas; p<0.01 for each) and for fat (68-fold [23-199] and 49-fold [18-137], respectively; p<0.01), but not for skin. Compared with normal areas, putrescent areas of arteries showed increased iNOS expression (1280-fold [598-3153]; p<0.01). Compared with normal areas, TNFalpha and IL-1beta were increased in putrescent areas of arteries (223-fold and 41-fold, respectively; p<0.01 for each). PBMCs and tissue macrophages expressed iNOS. Plasma nitrite/nitrate concentrations inversely correlated with mean arterial pressure and systemic vascular resistance. INTERPRETATION: In human septic shock we found that iNOS activity is compartmentalised at the very site of infection and parallels expression of TNFalpha and IL-1beta. PBMCs and tissue macrophages can be a cellular source for iNOS.

Adipose Tissue↗

A 3-level prognostic classification in septic shock based on cortisol levels and cortisol response to corticotropin.

CONTEXT: The hypothalamic-pituitary-adrenal axis is a major determinant of the host response to stress. The relationship between its activation and patient outcome is not known. OBJECTIVE: To evaluate the prognostic value of cortisol levels and a short corticotropin stimulation test in patients with septic shock. DESIGN AND SETTING: Prospective inception cohort study conducted between October 1991 and September 1995 in 2 teaching hospital adult intensive care units in France. PARTICIPANTS: A total of 189 consecutive patients who met clinical criteria for septic shock. INTERVENTION: A short corticotropin stimulation test was performed in all patients by intravenously injecting 0.25 mg of tetracosactrin; blood samples were taken immediately before the test (T0) and 30 (T30) and 60 (T60) minutes afterward. MAIN OUTCOME MEASURES: Twenty-eight-day mortality as a function of variables collected at the onset of septic shock, including cortisol levels before the corticotropin test and the cortisol response to corticotropin (delta max, defined as the difference between T0 and the highest value between T30 and T60). RESULTS: The 28-day mortality was 58% (95% confidence interval [CI], 51%-65%) and median time to death was 17 days (95% CI, 14-27 days). In multivariate analysis, independent predictors of death (P < or = .001 for all) were McCabe score greater than 0, organ system failure score greater than 2, arterial lactate level greater than 2.8 mmol/L, ratio of PaO2 to fraction of inspired oxygen no more than 160 mm Hg, cortisol level at T0 greater than 34 microg/dL and delta max no more than 9 microg/dL. Three groups of patient prognoses were identified: good (cortisol level at T0 < or = 34 microg/dL and delta max > 9 microg/dL; 28-day mortality rate, 26%), intermediate (cortisol level at T0 34 microg/dL and delta max < or = 9 microg/dL or cortisol level at T0 > 34 microg/dL and delta max > 9 microg/dL; 28-day mortality rate, 67%), and poor (cortisol level at T0 > 34 microg/dL and delta max < or = 9 microg/dL; 28-day mortality rate, 82%). CONCLUSION: Our data suggest that a short corticotropin test has a good prognostic value and could be helpful in identifying patients with septic shock at high risk for death.

Adult↗

Validity and reliability of two muscle strength scores commonly used as endpoints in assessing treatment of myasthenia gravis.

Valid and reliable measurements of muscle impairment are needed to assess therapeutic efficacy in patients with generalized myasthenia gravis (MG). In 22 patients we compared the validity and interobserver reliability of two scoring methods commonly used as main endpoints in clinical trials, i.e., the Myasthenic Muscle Score (MMS) ranging from 0 to 100 (normal) and the Quantified Myasthenia Gravis Strength Score (QMGSS) ranging from 0 (normal) to 39. Each score is correlated more with functional scale and less with the patient's self-evaluation. Using intraclass correlation we found strong agreement between observers for both the MMS (r = 0.906) and the QMGSS (r = 0.905). The correlation between MMS and QGMSS was high (r = 0.87). The reliability of neither score depended on any specific item, since the removal of individual items did not significantly alter the intraclass correlation coefficient (ranging from 0.86 to 0.93).

Adult↗

Association of herpes simplex virus encephalitis and paraneoplastic encephalitis - a clinico-pathological study.

A 57 year-old woman developed acute limbic encephalitis and brainstem dysfunction. Anti-HU antibodies were repeatedly detected in serum and CSF. Postmortem examination showed necrotic and hemorrhagic lesions in the temporal lobes characteristic of herpes simplex virus encephalitis, which was confirmed by immunocytochemistry, and Purkinje cell loss with proliferation of Bergman glia and myelin loss in the external aspect of the dentate nuclei characteristic of paraneoplastic encephalitis. PCR-assay performed on temporal tissue extracts was positive for HSV-1. There was no identifiable neoplasm. This unusual association raises the possibility of a link between the two diseases.

Antibodies↗

[Contribution of intravenous immunoglobulins to the treatment of myasthenia].

Myasthenia Gravis (MG) is an autoimmune disease characterized by the production of auto antibodies directed against the acetylcholine receptor of the neuro-muscular synapse. The signs and symptoms are a muscular deficit involving the spinal or cranial muscles. The degree of weakness changes spontaneously over shorter or longer periods. Some exacerbations, called myasthenia crisis, involve the respiratory muscle and are life-threatening. The prognosis of these crisis has been transformed by the use of mechanical ventilation. Treatments directed on immune-regulation such as thymectomy, corticosteroids or immunossupressive drugs contribute to the improvement in functional status and reduce the risk of exacerbation. Plasma exchanges lead to a rapid improvement of weakness during exacerbations. They are, despite the lack of controlled study, the reference treatment for acute exacerbations. More recently, high doses of immunoglobulins have been proposed and a controlled study has shown that they could be an alternative for the treatment of acute exacerbations of MG. Indication of immunoglobulin in the long term management of MG is not established.

Adrenal Cortex Hormones↗

[Corticotherapy in severe infectious states].

Septic shock is one of the leading cause of death in modern countries. Scientists have made huge improvement in the understanding of mechanisms of inflammation, and the sequence of activation of the various pro and anti-inflammatory markers is now well known. By contrary, physicians have failed to improve survival from septic shock, in spite of the development of specific targets of the various points of the cytokine cascade sought to have a key role in host survival to sepsis. Corticosteroids were among the first anti-inflammatory drugs, which have been tested in high quality randomised controlled trials. These trials clearly showed that patients with septic shock are unlikely to benefit from a short course of a large dose of an anti-inflammatory steroid. More recent findings highlighting the role of the integrity of the hypothalamic-pituitary -adrenal axis to appropriately respond to a septic insult, have led to a reappraisal of the use of steroids in septic shock. Several high quality randomised controlled trials have evaluated the efficacy and safety of a prolonged treatment with low dose hydrocortisone in severe sepsis. These trials strongly suggested that this strategy of corticotherapy reduced the morbidity of septic shock and may favourably affect survival from septic shock.

Adrenal Cortex Hormones↗

[Treatment of myasthenia: role of corticoids and immunosuppressive agents].

OPTIMAL TREATMENT: Myasthenia is an autoimmune disease related to a recognized autoantigen. Treatment is aimed at providing symptomatic relief or a pathophysiological effect. The latter approach, with corticosteroid and immunosuppressor regimens, has proven to be effective, improving functional improvement, but at the cost of prolonged treatment over several years with the risk of major adverse effects. Indications and treatment modalities must be carefully weighed. INITIATING TREATMENT: The question is when to start corticosteroids or immunosuppressors. A regimen should be initiated when, after all aggravating factors have been eliminated, a well-conducted anticholinesterase treatment remains ineffective with persistent major muscular deficit and brain stem disorders (deglutition, ventilation). Corticosteroids and immunosuppressors are also indicated if acute episodes occur, even if they regress. TREATMENT REGIMENS: To date, no controlled study has validated any particular therapeutic protocol. Both corticosteroids and immunosuppressors are known to provide major improvement in 80% of patients. No one immunosuppressor has been found to be more effective, but azathioprine is prescribed preferentially because of its lower profile of adverse effects. IN CLINICAL PRACTICE: Response is relatively rapid to corticosteroids which are recommended in combination with azathioprine at treatment onset for more severe cases (brain stem signs or recurrent acute episodes) or secondarily in case of resistance to moderate dose corticosteroids. In all cases, treatment must be prolonged for several years. Relapses are frequent after treatment withdrawal.

Acute Disease↗

Treatment of children and adolescents with non-Hodgkin's lymphoma (results based on the NHL Berlin-Frankfurt-Münster 90 protocols).

BACKGROUND: To determine the feasibility and results of treating children with non-Hodgkin's lymphomas (NHL) according to very intensive protocols based on the German Berlin Frankfurt Münster NHL 90 study. METHODS AND RESULTS: From 1991 until 1995 eighty two patients less than 18 years of age with NHL were admitted to our department. Sixty three of them were eligible for the study. The entire group consisted of 43 males and 20 females (ratio 2.1:1). Median age was 10 2/12 years. Eleven had stage I disease, 4 stage II, 29 stage III and 19 stage IV disease. Histologies represented were: large cell lymphoma 22, lymphoblastic lymphoma 19, and Burkitt lymphoma 10 patients. In 12 cases the immunophenotype was not further classified as to B-cell or T-cell subtype. Patients were stratified into the therapy groups "B" or "non B" according to histopathology, clinical stage and LDH level. Therapy for the B group consisted of 2, 4 or 6 courses of intensive 5 day pulses of 6 drugs. Patients in the non B group received the protocol for acute lymphoblastic leukemia including reinduction and CNS irradiation for advanced stages. At a median follow-up of 35 months the probability of event free survival (pEFS) at 5 years 70% and overall survival 73% for entire group. For therapy group B pEFS was 76%. The non B therapy group had a pEFS 60% (p = 0.22). There was a significantly better outcome for children classified as stage I and II. There was no statistical difference between stage III and IV. Treatment results were comparable between NHL subtypes, except for large cell lymphomas, which did significantly better (pEFS 90%). CONCLUSIONS: The use of protocols based on BFM 90 study in the Czech Republic was feasible. The pEFS are approximately 10% lower than the German study but comparable to some other studies. Outcome for large cell lymphomas was excellent. Reduction of treatment related complication and mortality rate as well as more precise classification are required.

Adolescent↗

Inappropriate sympathetic activation at onset of septic shock: a spectral analysis approach.

The autonomic cardiovascular control was investigated in 10 patients with septic shock, 10 patients with sepsis syndrome, and six tilted healthy subjects. Overall variability, high- and low-frequency components (AUC, HF, and LF, beats/min(2)/Hz or mm Hg(2)/Hz) from heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressures spectra were obtained from 5-min recordings. LF(HR)/HF(HR) and the square root of LF(SBP)/LF(HR) (alpha) were used as indices of sympathovagal interaction and baroreflex control of the heart, respectively. Compared with tilted control subjects and patients with sepsis syndrome, septic shock is characterized by reduction in: (1) HR variability, i.e., decreased AUC(HR) (p = 0.007), LF(HR) (p = 0.002), and LF(HR)/HF(HR) (p = 0.0002); (2) DBP variability, i.e., decreased AUC(DBP) (p = 0.003) and LF(DBP) (p = 0.001), (3) alpha (p = 0.003). In septic shock, LF(HR)/HF(HR), alpha, and LF(DBP) correlated with mean blood pressure (r = 0.67, p = 0.04, r = 0.64, p = 0.03, and r = 0.88, p = 0.0008, respectively), and with plasma norepinephrine levels (r = -0.65, p = 0.03, r = -0.79, p = 0.006, and r = -0.69, p = 0.03, respectively). In conclusion, onset of septic shock is characterized by high concentrations of circulating catecholamines but impaired sympathetic modulation on heart and vessels, suggesting that central autonomic regulatory impairment contributes to circulatory failure.

Adult↗

Mechanisms underlying effects of nocturnal ventilation on daytime blood gases in neuromuscular diseases.

The hypothesis that, in neuromuscular and chest wall diseases, improvement in central respiratory drive explains the effects of night-time ventilation on diurnal gas exchanges was tested. The effects at 6 months, 1, 2 and 3 yrs of intermittent positive pressure ventilation (IPPV) on arterial blood gas tension, pulmonary function, muscle strength, sleep parameters, respiratory parameters during sleep and ventilatory response to CO2 were evaluated in 16 consecutive patients with neuromuscular or chest wall disorders. As compared with baseline, after IPPV daytime arterial oxygen tension (Pa,O2) increased (+2.3 kPa at peak effect) and arterial carbon dioxide tension (Pa,CO2) and total bicarbonate decreased (-1.8 kPa and -5 mmol x L(-1), respectively) significantly; vital capacity, total lung capacity, maximal inspiratory and expiratory pressures and alveolar-arterial oxygen gradient did not change; the apnoea-hypo-opnoea index and the time spent with an arterial oxygen saturation (Sa,O2) value <90% decreased (-24 and -101 min, respectively), sleep efficiency and mean Sa,O2 increased (+16% and +5%, respectively); and ventilatory response to CO2 increased (+4.56 L x min(-1) x kPa(-1)) significantly. The reduction in Pa,CO2 observed after IPPV correlated solely with the increase in the slope of ventilatory response to the CO2 curve (r=-0.68, p=0.008). In neuromuscular or chest wall diseases, improvement of daytime hypoventilation with nocturnal intermittent positive pressure ventilation may represent an adaptation of the central chemoreceptors to the reduction of profound hypercapnia during sleep or reflect change in the quality of sleep.

Adult↗

Selective impairment of serum antibody repertoires toward muscle and thymus antigens in patients with seronegative and seropositive myasthenia gravis.

We analyzed the antibody (Ab) repertoires of IgM and IgG of patients with seropositive and patients with seronegative myasthenia gravis (MG) toward self antigens by means of a quantitative immunoblotting technique using normal human tissue extracts as sources of self antigens. Repertoires of reactivities of IgG and IgM with liver, kidney and stomach antigens were conserved between myasthenic patients and controls. IgG and IgM Ab repertoires toward muscle antigens differed significantly between patients with seropositive MG and healthy donors, as assessed by multiparametric statistical analysis. Patterns of Ab reactivities to muscle antigens were similar in patients with seronegative MG and healthy controls. Antibody repertoires of IgG and IgM toward thymus antigens of both seropositive and seronegative MG patients, differed significantly from those of healthy individuals. Our results indicate that MG is characterized by a selective impairment of self-reactive Ab repertoires toward muscle and thymus antigens. The observation that self-reactive Ab repertoires toward thymus antigens are similar in patients with seropositive and seronegative MG suggests that both forms of MG share common immunopathological features.

Adult↗