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1.
Purpose: Spray-freeze drying (SFD) is a recently applied method to develop pharmaceutical powders. This study aimed to analyze the competence of Trehalose, Mannitol, Lactose, and Sorbitol instability and aerosolization of Immunoglobulin G (IgG) via SFD.

Methods: Induced soluble aggregates were quantified at 0 and 3?months, and 45?°C using size-exclusion chromatography. Conformation and thermogravimetric assessments were done by Fourier transform infrared spectroscopy and differential scanning calorimetry. Laser light scattering was performed to determine the particle sizes. Aerodynamic features were characterized by twin stage impinger and scanning electron microscopy.

Results: Although sugars/polyols preferably stabilized IgG following the process, storage stabilization was achieved in Trehalose, Trehalose-Lactose, Lactose, and Trehalose-Mannitol-based powders with soluble aggregates <5%. The conformation of antibody was preserved with β sheet content from 66.28% to 76.37%. Particle sizes ranged from 5.23 to 8.12?µm. Mannitol exhibited the best aerodynamic behavior, fine particle fraction (FPF: 70%) but high degree of protein aggregation during storage.

Conclusions: SFD could favorably stabilize antibody using Trehalose and its combination with Lactose and Mannitol, and also, Lactose alone. Sorbitol disturbed IgG powder recovery. Incorporation of other types of excipient is required for efficient respiratory delivery of IgG molecules.  相似文献   

2.
Journal of Gastroenterology - Sarcopenia (severe muscle depletion) is a prevalent muscle abnormality in patients with cirrhosis that confers poor prognosis both pre- and post-liver transplantation....  相似文献   
3.
Among many conventional techniques, nuclear techniques have shown to be faster, more reliable, and more effective in detecting explosives. In the present work, neutrons from a 5 Ci Am-Be neutron source being in water tank are captured by elements of soil and landmine (TNT), namely (14)N, H, C, and O. The prompt capture gamma-ray spectrum taken by a NaI (Tl) scintillation detector indicates the characteristic photo peaks of the elements in soil and landmine. In the high-energy region of the gamma-ray spectrum, besides 10.829 MeV of (15)N, single escape (SE) and double escape (DE) peaks are unmistakable photo peaks, which make the detection of concealed explosive possible. The soil has the property of moderating neutrons as well as diffusing the thermal neutron flux. Among many elements in soil, silicon is more abundant and (29)Si emits 10.607 MeV prompt capture gamma-ray, which makes 10.829 MeV detection difficult. The Monte Carlo simulation was used to adjust source-target-detector distances and soil moisture content to yield the best result. Therefore, we applied MCNP4C for configuration very close to reality of a hidden landmine in soil.  相似文献   
4.
OBJECTIVES: To characterise mycobacterial clinical isolates based on amplification of the rpoB gene. SETTING: One hundred and thirty-five mycobacterial isolates cultured from suspected pulmonary tuberculosis (TB) patients were identified phenotypically. Molecular characterisation of the isolates was performed based on amplification of the rpoB gene, using duplex polymerase chain reaction (DPCR), PCR-restriction fragment length polymorphism (RFLP) and nested PCR-based sequence analysis techniques. RESULTS: The DPCR assay identified 129 of 135 (95.5%) clinical isolates as Mycobacterium tuberculosis complex species. Restriction enzyme analysis of the rpoB PCR product using Hind II identified 134 of the 135 (99.3%) isolates as M. tuberculosis complex, while nested PCR sequence analysis of the rpoB gene identified 133/133 examined isolates (100%) as M. tuberculosis species. No mycobacteria other than M. tuberculosis (MOTT) were detected among the studied isolates. CONCLUSION: DPCR, PCR/RFLP Hind II and nested PCR sequence analysis of the rpoB gene techniques showed comparable efficiency in the characterisation of Mycobacterium isolates. Nested PCR sequence analysis of the rpoB gene was superior to PCR/RFLP for characterisation of suspected M. tuberculosis isolates, while the DPCR technique showed less sensitivity. As PCR-RFLP requires less sophisticated laboratory facilities than nested PCR sequence analysis, it would be more appropriate to be adopted for accurate characterisation of mycobacteria in countries with a weak infrastructure.  相似文献   
5.
PURPOSE: To evaluate qualitative wall motion assessment vs. quantitative wall thickening for the assessment of subtle changes in myocardial systolic function using cine MRI. METHODS: Cine MR images were obtained in 5 canines with a significant coronary artery stenosis and in 2 controls on a 1.5T scanner. Qualitative results were obtained using a numerical scoring system; quantitative analysis was performed using a semi-automatic segmentation program. The techniques were matched and compared using Spearman correlations. RESULTS: All correlations in the experimental group revealed significant but weak to moderate relationships between the qualitative and quantitative results (e.g., at-risk tissue rho = 0.363, p < 0.0001; remote tissue rho = 0.275, p = 0.0002), with each identifying changes in regional function that ensued following creation of the stenosis. Intra-observer variability was reasonable in both methods when repeat analysis on a subset of the data was performed, with both techniques showing a significant correlation between the repeated measurements (quantitative - rho = 0.52, p < 0.0001; qualitative - rho = 0.54, p < 0.0001). CONCLUSION: Both methods were able to detect very limited wall motion abnormalities present in the canines with significant stenosis and either method gives comparable results.  相似文献   
6.
PURPOSE: Although venous air embolism is a well recognized complication within most surgical subspecialties, it has only been reported recently during eye surgery in one adult, and never before in a child. We describe the case of a 17-month-old boy who sustained a possible air embolism during repair of an open trauma of his right eye. CLINICAL FEATURES: A vitrectomy through the pars plana with air-fluid exchange of the posterior chamber was performed under general anesthesia to remove a foreign body which had impaled the optic nerve. A few minutes after removal of the foreign body, a notable decrease in end-tidal CO(2), oxygen saturation and arterial blood pressure occurred, requiring administration of a high inspired oxygen fraction and vasopressors. Venous air embolism was strongly suspected after other causes of a decrease of end-tidal CO(2) and hypoxemia had been excluded. An arterial blood gas confirmed hypoxemia and respiratory acidosis. CONCLUSION: Although venous air embolism is a rare complication of eye surgery, it should nevertheless be considered as a possible complication during air-fluid exchange vitrectomy in children.  相似文献   
7.
A single application of crude coal tar (CCT) solution (USP) to the skin of neonatal rats was shown to induce epidermal and hepatic cytochrome P-450(P-450)-dependent monooxygenase activities. To further characterize the induction response, in this study we have utilized highly specific monoclonal antibodies (MoAb) 1-7-1, 2-66-3, and 1-98-1 directed against highly purified rat liver P-450s induced by 3-methyl-cholanthrene, phenobarbital and ethanol, respectively. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of hepatic microsomes prepared from CCT-treated animals showed a significant increase in the coomassie blue stainable proteins in the P-450 region; however, this was not evident in epidermal microsomes. Immunoblot analysis of epidermal and hepatic microsomes with MoAb 1-7-1 revealed strong immunoprecipitin bands in both tissues. MoAb 2-66-3 showed significant immunoreactivity only with hepatic microsomes. Interestingly, CCT treatment resulted in suppression of immunoreactivity with MoAb 1-98-1 in hepatic microsomes. MoAb 1-7-1 and 2-66-3 exhibited concentration-dependent inhibitory effects in aryl hydrocarbon hydroxylase and 7-ethoxycoumarin-O-deethylase activities induced by CCT application. MoAb 1-7-1 was substantially more effective in this respect. Epidermal and hepatic microsomes prepared from CCT-treated rats showed significantly greater metabolism of benzo(a)pyrene (BP). MoAb 1-7-1 and MoAb 2-66-3 inhibited BP metabolism in both the tissues. However, MoAb 1-7-1 was more inhibitory in this regard as compared to MoAb 2-66-3. These studies indicate that topical application of therapeutic CCT to the skin of neonatal rats results in induction of P-450 isozyme c in epidermis and isozymes b and c in liver, and that this induction is associated with the suppression of P-450 isozyme j in liver.  相似文献   
8.
9.
OBJECTIVE--To compare outcome after infarction in South Asian patients, comprising Indians, Pakistanis, Bangladeshis and individuals of East African origin, in Birmingham with that in white patients in the same city. DESIGN--A prospective case-control study. SETTING--Three large district general hospitals. PATIENTS--102 South Asian patients discharged from hospital after an acute myocardial infarction were matched for age, sex, time and season of infarct, and hospital of admission with white patients. MAIN OUTCOME MEASURES--Survival and complication. RESULTS--There was no significant difference in survival or complications during the four years after an acute myocardial infarction in South Asian and white patients. CONCLUSION--The survival and clinical course of South Asian and white patients discharged after an acute myocardial infarction were similar over a four year period.  相似文献   
10.
The aim of this study was to describe the effects of aluminum on the stromal cells of rat bone marrow using a combination of in vivo exposure and in vitro culture of bone marrow. The toxic effects of aluminum are manifested by a decrease in the erythrocyte count and hemoglobin level in the peripheral blood. Aluminum stimulated an increase in the number of fibroblasts while the macrophage count dropped. The number of adipocytes remained unaffected. An increase in mean corpuscular hemoglobin (MCH) was also found in the peripheral blood of experimental animals.  相似文献   
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