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81.
Stem cell factor (SCF) has been shown to synergize with filgrastim to mobilize CD34(+) cells into the peripheral blood. To determine if addition of SCF to chemotherapy and filgrastim reduces the number of leukaphereses required to achieve a target yield of 5 x 10(6) CD34(+) cells/kg, 102 patients with multiple myeloma were randomized to receive mobilization chemotherapy with cyclophosphamide (4 g/m(2)) and either SCF (20 micrograms/kg/d) combined with filgrastim (5 micrograms/kg/d) or filgrastim alone (5 micrograms/kg/d), administered daily until leukaphereses were completed. After collection, patients were treated with myeloablative therapy supported by autologous peripheral blood progenitor cell (PBPC) infusion and filgrastim (5 micrograms/kg/d). There was a significant difference between the treatment groups in the number of leukaphereses required to collect 5 x 10(6) CD34(+) cells/kg (median of 1 v 2 for SCF + filgrastim and filgrastim alone, respectively, P =.008). Patients receiving the combination of SCF plus filgrastim had a 3-fold greater chance of reaching 5 x 10(6) CD34(+) cells/kg in a single leukapheresis compared with patients mobilized with filgrastim alone. The median CD34(+) cell yield was significantly increased for the SCF group in the first leukapheresis (11.3 v 4.0 x 10(6)/kg, P =.003) and all leukaphereses (12.4 v 8.2 x 10(6)/kg, P =.007). Total colony-forming unit-granulocyte-macrophage (CFU-GM) and mononuclear cell counts were also significantly higher in the SCF group in the first leukapheresis and in all leukaphereses. As expected for patients mobilized to an optimal CD34(+) cell yield, the time to engraftment was similar between the 2 treatment groups. Cells mobilized with the combination of SCF plus filgrastim were thus considered effective and safe for achieving rapid engraftment. Treatment with SCF plus filgrastim was well tolerated, with mild to moderate injection site reactions being the most frequently reported adverse events. There were no serious allergic-like reactions to SCF. The addition of SCF to filgrastim after cyclophosphamide for PBPC mobilization resulted in a significant increase in CD34(+) cell yield and a concomitant reduction in the number of leukaphereses required to collect an optimal harvest of 5 x 10(6) CD34(+) cells/kg.  相似文献   
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 A prospective clinical microbiological study of pleural fluid samples was conducted to investigate the etiology of pleural effusions and to evaluate two different methods for transport and culture of these samples. A total of 245 pleural fluid specimens were inoculated into a transport vial, an aerobic and an anaerobic blood culture vial, and a sterile tube. One hundred nine samples were from infectious patients and 128 from noninfectious patients. Gram stain had a sensitivity of 48% and a specificity of 100% as compared to culture. Of the total, 15.5% of the samples were positive for microorganisms, and 60% of the positive samples were nonpurulent pleural fluid. Single-organism growth was found in 23 samples (60.5%). Sixty-three microorganisms were isolated: 25 (39.7%) aerobic, 22 (35%) anaerobic, 13 (20.6%) mycobacteria, and three (4.7%) fungi. Of the 25 positive samples, excluding those samples that grew mycobacteria, nine (36%) were positive exclusively in the blood culture vials. Twelve organisms were isolated, only one of which did not grow in the anaerobic vial. Two (8%) samples were positive by conventional culture only, and 14 (56%) were positive by both methods. The microorganism isolation rate obtained with use of blood culture vials was significantly greater than that obtained with the conventional method of transport and culture. Sixty-three percent of the empyema patients had an associated underlying pathology, pneumonia being the most frequent. In conclusion, for microbiological study of pleural fluid, it seems appropriate to inoculate all samples, including nonpurulent samples, into both a sterile tube and an anaerobic blood culture vial.  相似文献   
83.

Background

The risk of skin cancer in patients treated with narrowband (NB) UV-B phototherapy is not well understood. Although experimental studies have shown that there is a risk, clinical studies have not detected an increased incidence of cancer following treatment. The aim of this study was to determine the incidence of nonmelanoma skin cancer (NMSC) in patients treated with NB UV-B phototherapy at a tertiary care hospital in the Mediterranean area.

Material and methods

We conducted a retrospective chart review of 474 patients who received whole-body NB UV-B phototherapy at our hospital between 2002 and 2016 and identified those diagnosed with NMSC during follow-up. We calculated the corresponding crude and standardized incidence rates and compared these with rates in the general population in a similar geographic area.

Results

Of the 474 patients, 193 (40.7%) were men and 281 (59.3%) were women. The mean (SD) follow-up period was 5.8 (3) years. The prevalence of NMSC at the end of the study period was 1.9% and the standardized incidence was 108.3 cases per 100 000 patient-years. The SIR of 1.9 in the study group was not significantly different from that of the general population. The number of patients who needed to be treated with NB UV-B phototherapy for 1 case of NMSC to occur was 1900.

Conclusion

NB UV-B phototherapy does not appear to be associated with an increased risk of NMSC  相似文献   
84.

Background

High-frequency deep brain stimulation (DBS) has become a widespread therapy used in the treatment of Parkinson's Disease (PD) and other diseases. Although it has proved beneficial, much recent attention has been centered around the potential of new closed-loop DBS implementations.

Objective

Here we present a new closed-loop DBS scheme based on the phase of the theta activity recorded from the motor cortex. By testing the implementation on freely moving 6-OHDA lesioned and control rats, we assessed the behavioral and neurophysiologic effects of this implementation and compared it against the classical high-frequency DBS.

Results

Results show that both stimulation modalities produce significant and opposite changes on the movement and neurophysiological activity. Close-loop stimulation, far from improving the animals' behavior, exert contrary effects to those of high-frequency DBS which reverts the parkinsonian symptoms. Motor improvement during open-loop, high-frequency DBS was accompanied by a reduction in the amount of cortical beta oscillations while akinetic and disturbed behavior during close-loop stimulation coincided with an increase in the amplitude of beta activity.

Conclusion

Cortical-phase-dependent close-loop stimulation of the STN exerts significant behavioral and oscillatory changes in the rat model of PD. Open-loop and close-loop stimulation outcomes differed dramatically, thus suggesting that the scheme of stimulation determines the output of the modulation even if the target structure is maintained. The current framework could be extended in future studies to identify the correct parameters that would provide a suitable control signal to the system. It may well be that with other stimulation parameters, this sort of DBS could be beneficial.  相似文献   
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Type 1 diabetes mellitus (T1DM) is associated with neurocognitive dysfunction and astrogliosis. Physical exercise prevents cognitive impairments and induces important brain modifications. The aim of our study was to investigate the effect of treadmill exercise on spatial memory and astrocytic function in the hippocampus of a T1DM model. Fifty-seven Wistar rats were divided into four groups: trained control (TC) (n = 15), non-trained control (NTC) (n = 13), trained diabetic (TD) (n = 14) and non-trained diabetic (NTD) (n = 15). One month after streptozotocin-induced diabetes, exercise groups were submitted to 5 weeks of physical training, and then, all groups were assessed in the novel object-placement recognition task. Locomotor activity was analyzed in the open field apparatus using Any-maze software. The expression of glial fibrillary acidic protein (GFAP) and S100B in hippocampus and cerebrospinal fluid were measured using ELISA assay, and hippocampal GFAP immunoreactivity was evaluated by means of immunohistochemistry and optical densitometry. The results showed that physical exercise prevents and/or reverts spatial memory impairments observed in NTD animals (P < 0.01). Decreased locomotor activity was observed in both the NTD and TD groups when compared with controls (P < 0.05). ELISA and immunohistochemistry analyzes showed there was a reduction in GFAP levels in the hippocampus of NTD animals, which was not found in TD group. ELISA also showed an increase in S100B levels in the cerebrospinal fluid from the NTD group (P < 0.01) and no such increase was found in the TD group. Our findings indicate that physical exercise prevents and/or reverts the cognitive deficits and astroglial alterations induced by T1DM.  相似文献   
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