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81.
82.
To improve the selection of donors for allogeneic stem cell transplantation, it is important to identify reliable parameters that predict CD34+-cell yields after granulocyte-colony stimulating factor (G-CSF)-induced peripheral blood stem cell (PBSC) mobilization. We retrospectively investigated the peripheral blood (PB) kinetics of white blood cells (WBCs), CD34+ cells, matrix metalloproteinases (MMP)-9 and -2, and tissue inhibitors of metalloproteinases (TIMP)-1 and -2 in 15 healthy donors during their treatment with G-CSF. All donors received 10 microg/kg of recombinant human G-CSF once a day subcutaneously. Leukapheresis was initiated after 4 days of G-CSF treatment, and G-CSF treatment continued until the last day of leukapheresis. WBC and CD34+ cell numbers in the PB rose after 2 and 3 or 4 days of G-CSF treatment, respectively. The PB CD34+ cell numbers on day 4 correlated weakly with the increase in WBC counts from day 1 to day 2 (R(2) = 0.254, P = 0.056). There were also positive correlations between the CD34+ cell numbers in the PBSC products on day 4 and the CD34+ cells in the PB on days 1 and 4 (R(2) = 0.768, P < 0.0001 and R(2) = 0.816, P < 0.0005, respectively). The MMP-9 plasma levels on days 1 and 4 also correlated positively with the day 4 circulating CD34+ cell numbers (R(2) = 0.393, P < 0.05 and R(2) = 0.406, P = 0.01, respectively). In conclusion, the CD34+ cell numbers in the PB steady state may be a useful parameter selecting allogeneic PBSC donors.  相似文献   
83.
Vasospasm is a phenomenon often present in human cases after subarachnoidal haemorrhage. Its aetiology and pathophysiology are unknown. As a resultcases of vasospasm do not respond to any known pharmacological therapy. We present in this paper; a practical application of intravascular surgery for vasospasm. In this procedure the requirement for a portable digital subtraction unit, transcranial Doppler sonography, and being able to determine quickly the neurological state of the patient are very important points. The use of monitoring equipment is especially indispensable during the carrying out of percutaneous transluminal angioplasty (PTA), which should be performed as soon as possible after the occurrence of vasospasm. The case of a 54-year-old male patient suffering from a ruptured anterior cerebal artery aneurysm was studied. Neck clipping was performed on the second day. On the fifth day the neurological state was stupor, and transcranial Doppler sonography (TCD) revealed a flow velocity of over 100 cm s–1. PTA was performed on the sixth day. The bilateral middle cerebral artery was dilated and the flow velocity slowed to within the normal range. The neurological state improved to clouding of consciousness after PTA. On the eighteenth day, the patient's conciousness and bilateral carotid angiograms revealed the vessels to be dilated still. It was concluded that PTA therapy, and the use of a portable digital substraction unit and TCD sonography, for vasospasm caused by subarachnoidal haemorrhage is useful and effective.  相似文献   
84.
Propionibacterium acnes is the only microorganism isolated from sarcoid lesions by bacterial culture. Numerous P. acnes genomes are found in lymph node samples from Japanese and European patients with sarcoidosis, whereas a few genomes are found in some non-sarcoid samples. The high frequency and specificity of detecting P. acnes within sarcoid granulomas suggests that this indigenous bacterium causes granuloma formation in many patients with sarcoidosis. P. acnes is the most common commensal bacterium in the lungs and lymph nodes. Occasional detection of P. acnes in non-granulomatous areas of these organs from non-sarcoid patients suggests that host factors are more critical than agent factors in the etiology of sarcoidosis. A particular protein, i.e., trigger factor, from P. acnes causes a cellular immune response only in sarcoid patients. The P. acnes trigger-factor protein induces pulmonary granulomas in mice sensitized with the protein and adjuvant, but only in those with latent P. acnes infection in their lungs. Eradication of P. acnes by antibiotics prevents the development of granulomas in this experimental model. P. acnes can cause latent infection in the lung and lymph nodes and persists in a cell wall-deficient form. The dormant form is endogenously activated under certain conditions and proliferates at the site of latent infection. In patients with P. acnes hypersensitivity, granulomatous inflammation is triggered by intracellular proliferation of the bacterium. Proliferating bacteria may escape granulomatous isolation, spreading to other organs. Latent P. acnes infection in systemic organs can be reactivated by another triggering event, leading to systemic sarcoidosis.  相似文献   
85.
Background: In airway smooth muscle, muscarinic receptor stimulation is thought to increase calcium (Ca2+) sensitivity via a guanosine 5'-triphosphate (GTP)-binding protein/protein kinase C (PKC)-mediated mechanism. This study tested the hypothesis that halothane reduces Ca2+ sensitivity during muscarinic receptor stimulation by inhibiting these second messenger pathways.

Methods: A beta-escin permeabilized canine tracheal smooth muscle preparation was used in which the cytosolic Ca2+ concentration ([Ca sup 2+]i) is controlled and the GTP-binding protein/PKC pathways remain intact and can be activated. The muscarinic receptor was activated with acetylcholine plus GTP; the GTP-binding proteins were directly activated with a nonhydrolyzable form of GTP, guanosine 5'-O-(3-thiotriphosphate; GTP gamma S); and PKC was directly activated with the PKC agonist phorbol 12,13-dibutyrate (PDBu).

Results: Free Ca2+ caused a concentration-dependent increase in force. Acetylcholine plus GTP significantly decreased the median effective concentration for free Ca2+ from 0.52 +/- 0.06 micro Meter to 0.21 +/- 0.02 micro Meter, demonstrating an increase in Ca2+ sensitivity. Halothane (0.99 +/- 0.04 mM, equivalent to approximately 4 minimum alveolar concentration in dogs) significantly attenuated this increase in Ca2+ sensitivity induced by acetylcholine plus GTP, increasing the median effective concentration for free Ca2+ from 0.21 +/- 0.02 micro Meter to 0.31 +/- 0.03 micro Meter. However, halothane did not affect the increases in Ca2+ sensitivity induced by GTP gamma S or PDBu.  相似文献   

86.
On the bases of the initial and follow-up results of patients who underwent percutaneous transluminal coronary angioplasty (PTCA) and percutaneous transvenous mitral commissurotomy (PTMC), the proper applications of these interventional therapies were discussed. The efficacy of PTMC on valvotomy was comparable to open mitral commissurotomy and the procedural safety was noticed. Our results supported the use of PTMC for patients with plicable mitral valve. Despite the good and acceptable results of elective PTCA, low initial success rate and high incidence of major cardiac events including mortality was noted in the group of urgent PTCA for patients with multivessel lesions. The urgent use of PTCA for refractory unstable angina should be restricted to selected patients without high-risk multivessel lesions.  相似文献   
87.
To expand the application of mitral valve reconstruction for pure mitral regurgitation due to diffuse leaflet prolapse, we have employed artificial chordae implantation using GPEP strips in 9 patients and 4-0 PTFE sutures in 20 patients since November 1986. The total number of GPEP strips implanted was 20 with a range from 1 to 4 (average 2.2 per patient) and 45 pairs of PTFE sutures with a range from 1 to 6 (average 2.3 per patient). There was one hospital death (3.4%). All other patients survived operation without valve-related complications except 1 patient who required reoperation for failure of mitral valve reconstruction. In 27 survivors free from reoperation, the amount of mitral regurgitation assessed postoperatively was none or trivial in 19 patients, mild in 7 and moderate in 1. All 27 patients improved to NYHA functional class I or II. So far, our results were no less acceptable than those with conventional procedures for mitral valve prolapse.  相似文献   
88.
Diagnosis of drug-induced pneumonia, which represents pulmonary toxicity caused by certain drugs, is difficult, as a large number of different drugs can elicit various immune-mediated diseases with distinct pathomechanisms. The drug-induced lymphocyte stimulation test (DLST) is widely used for diagnosing drug-induced pneumonia in Japan. Recent reports, however, indicate that DLST is not reliable for diagnosis of drug-induced pneumonia. To diagnose drug-induced pneumonia, a provocation test with the suspected drug is the most reliable method of assessing the relationship between the drug and pneumonia. We examined the correlation between the DLST and the provocation test in 6 cases of suspected drug-induced pneumonia. DLST was performed in all of the patients. The causes of pneumonia in all patients were confirmed by a provocation test. The DLST was positive in 3 of 6 cases of suspected drug-induced pneumonia, but the suspected drugs were ruled out by the provocation test. If we had relied solely on the DLST, these 3 cases would have been labeled as false allergy. The results of the DLST did not coincide with the results of the provocation test in any of the cases. Our results suggest that the DLST is not useful for the diagnosis of drug-induced pneumonia. Following provocation with the causative drug, reappearance of pulmonary infiltration was not observed in any of the cases. These findings indicate that a carefully performed provocation test is the safe and most reliable method.  相似文献   
89.
Deficiency of granulocyte-macrophage colony-stimulating factor (GM-CSF) in mice results in pulmonary alveolar proteinosis (PAP) from impaired surfactant catabolism by alveolar macrophages (AMs). Recently, we have shown that neutralizing anti-GM-CSF autoantibodies develop specifically in patients with idiopathic pulmonary alveolar proteinosis (iPAP). Analogous to murine PAP models, it is plausible that the autoantibodies reduce GM-CSF activity, resulting in AM dysfunction and surfactant accumulation. To examine this hypothesis, we estimated the neutralizing activity of the autoantibodies in the lungs of patients and characterized their biologic properties. GM-CSF bioactivity was completely abrogated in the bronchoalveolar lavage fluid (BALF) of patients with iPAP but not in healthy subjects. Autoantibodies were present in the alveoli in high concentrations and colocalized with GM-CSF. They recognized human GM-CSF with high avidity (K(AV) = 20.0 +/- 7.5 pM) and high specificity, reacting with its superstructure and neutralizing GM-CSF activity to a level 4000 to 58 000 times the levels of GM-CSF normally present in the lung. Although target epitopes varied among patients, GM-CSF amino acids 78 to 94 were consistently recognized. Thus, autoantibodies bind GM-CSF with high specificity and high affinity, exist abundantly in the lung, and effectively block GM-CSF binding to its receptor, inhibiting AM differentiation and function. Our data strengthen the evidence associating anti-GM-CSF autoantibodies with the pathogenesis of this disease.  相似文献   
90.
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