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71.
Riikka Laitinen Eero Suihko Kaisa Toukola Joakim Riikonen Kristiina Järvinen 《European journal of pharmaceutics and biopharmaceutics》2009,71(2):271-281
In this study, the dissolution rate of a poorly soluble drug, perphenazine (PPZ) was improved by a solid dispersion technique to permit its usage in intraoral formulations. Dissolution of PPZ (4 mg) in a small liquid volume (3 ml, pH 6.8) within one minute was set as the objective. PVP K30 and PEG 8000 were selected for carriers according to the solubility parameter approach and their 5/1, 1/5 and 1/20 mixtures with PPZ (PPZ/polymer w/w) were prepared by freeze-drying from 0.1 N HCl solutions. The dissolution rate of PPZ was improved with all drug/polymer mixture ratios compared to crystalline or micronized PPZ. A major dissolution rate improvement was seen with 1/5 PPZ/PEG formulation, i.e. PPZ was dissolved completely within one minute. SAXS, DSC and XRPD measurements indicated that solid solutions of amorphous PPZ in amorphous PVP or in partly amorphous PEG were formed. DSC and FTIR studies suggested that PPZ dihydrochloride salt was formed and hydrogen bonding was occurred between PPZ and the polymers. It was concluded that molecular mixing together with salt formation promoted the dissolution of PPZ, especially in the case of the 1/5 PPZ/PEG dispersion, making it a promising candidate for use in intraoral formulations. 相似文献
72.
Maria S?derlund-Venermo Anne Lahtinen Tuomas Jartti Lea Hedman Kaisa Kemppainen Pasi Lehtinen Tobias Allander Olli Ruuskanen Klaus Hedman 《Emerging infectious diseases》2009,15(9):1423-1430
Human bocavirus (HBoV) is a widespread respiratory virus. To improve diagnostic methods, we conducted immunoglobulin (Ig) G and IgM enzyme immunoassays with recombinant virus–like particles of HBoV as antigen. Acute-phase and follow-up serum samples from 258 wheezing children and single serum samples from 115 healthy adults in Finland were examined. Our assays had a sensitivity of 97% and a specificity of 99.5%. Of adults, 96% had immunity; none had an acute infection. Of 48 children with serologically diagnosed acute HBoV infections, 45 were viremic and 35 had virus in nasopharyngeal aspirates (NPAs). Of 39 HBoV NPA PCR–positive children co-infected with another virus, 64% had a serologically verified HBoV infection. HBoV caused illness of longer duration than rhinovirus and of equal severity to that of respiratory syncytial virus. Among children with bronchiolitis, >25% had acute HBoV infections. Accurate HBoV diagnosis requires serologic analysis or PCR of serum; PCR of NPAs alone is insufficient. 相似文献
73.
Mannerkorpi K Rivano-Fischer M Ericsson A Nordeman L Gard G 《Disability and rehabilitation》2008,30(3):213-221
PURPOSE: Patients with fibromyalgia (FM) and chronic widespread pain (CWP) find physical activity troublesome. The purpose was to develop a questionnaire to investigate the experience of physical activity in FM and CWP populations. METHOD: A questionnaire was developed from a qualitative study. After that, a total of 204 patients with FM or CWP completed the questionnaire. A factor analysis was conducted and the internal consistency was investigated. The relationship between the factors and pain, health status (the Fibromyalgia Impact Questionnaire, FIQ), distress (the Hospital Anxiety and Distress scale, HAD) and leisure time physical activity (the Leisure Time Physical Activity Instrument, LTPAI) was investigated. RESULTS: Five factors were identified: Physical Relaxation (PR), Well-being (WB), Activity Beliefs (AB), Activity-related Symptoms (AS) and Activity Habits (AH). Cronbach's alpha ranged from 0.57 to 0.86. The PR showed a correlation (rho 0.28, p < 0.01) with the FIQ Pain. The AS showed a correlation (rho 0.25, p < 0.01) with the FIQ total score, while the AH showed a correlation with the HAD Depression (0.26, p < 0.01) and with strenuous physical activity (LTPAI) (-0.32, p < 0.01). CONCLUSION: A new instrument was developed to study the experience of physical activity in persons with long-lasting pain. Five factors were identified using factor analysis, and three of them showed fair associations with FM symptoms, distress or physical activity. 相似文献
74.
75.
Maria Lagerstedt M.D. Kaisa Karvinen B.M. Minna Joki‐Erkkilä M.D. Riitta Huotari‐Orava M.D. Erna Snellman M.D. Satu‐Leena Laasanen M.D. 《Pediatric dermatology》2013,30(4):444-450
Childhood lichen sclerosus (LS) is a rare and often misdiagnosed inflammatory dermatitis with an unpredictable course. The complications of LS are architectural changes of the vulva; malignant transformation is possible. The objective of our study was to define the background and the long‐term course of childhood LS. A registery study identified 44 children with LS treated at Tampere University Hospital, Tampere, Finland, from 1982 to 2010. A questionnaire was sent to the identified patients and 15 responded. The clinical depiction of LS varied significantly. LS was diagnosed in only 16% of the patients at the referring unit. Autoimmune disorders were observed in 6 of the 44 patients. High prevalences of Turner's syndrome (2/44) and kidney disease (2/44) were noted. The majority of the patients were treated with topical corticosteroids. Eight developed architectural changes of the vulva. The questionnaire revealed that three of six patients who were asymptomatic at the end of the registery study follow‐up experienced a recurrence of symptoms. None of them were undergoing follow‐up. Nine of the 15 patients reported reduced quality of life. Childhood LS is a heterogeneous disease with a remarkable effect on quality of life. The misdiagnosis of childhood LS is common. The association between LS and autoimmune diseases should be noted. The high prevalence of Turner's syndrome raises questions regarding the influence of low estrogen levels on the development of LS. The prognosis cannot be predicted, so long‐term follow‐up is recommended. New tools for diagnosis and surveillance are needed. 相似文献
76.
Randell KM Honkanen RJ Tuppurainen MT Kröger H Jurvelin JS Saarikoski S 《Maturitas》2006,53(3):333-342
OBJECTIVES: Fracture risk and bone mineral density (BMD) among peri- and early postmenopausal women with leiomyomas requiring hysterectomy was evaluated. METHODS: We counted fractures among women with or without leiomyomas using data from the Kuopio Osteoporosis Study. The study population consisted of 6086 women aged 47-56 years with never-use of hormone replacement therapy (HRT) responding to the baseline and 5-year follow-up inquiries. Part of the sample (n=1271) underwent bone densitometry. RESULTS: Hysterectomy was carried out in 927 women, and 59% reported that this was attributable to leiomyomas. The hazard ratio (HR) was 0.68 (95% CI 0.49-0.94) for any and 0.73 (95% CI 0.43-1.26) for distal forearm fracture among women with leiomyomas compared to those without any. Among women postmenopausal at baseline, the corresponding HRs were 0.62 (95% CI 0.44-0.87) and 0.54 (95% CI 0.31-0.96); after adjusting for age, time since menopause weight, height and previous fracture 0.69 (95% CI 0.49-0.97) and 0.63 (95% CI 0.35-1.11). The baseline BMDs were 1.15 g/cm2 among hysterectomized leiomyoma and 1.12 g/cm2 (ns) among non-hysterectomized women at lumbar (L2-L4), and 0.94 and 0.93 g/cm2 (ns) at femoral sites. The follow-up lumbar BMDs were 1.13 and 1.09 g/cm2 (p<0.001) and the corresponding femoral values were 0.90 and 0.89 g/cm2 (ns), respectively. Among postmenopausal women, the corresponding baseline lumbar BMDs were 1.15 and 1.08 g/cm2 (p<0.001), femoral 0.93 and 0.90 g/cm2 (p=0.003); the follow-up lumbar BMDs 1.13 g/cm2 versus 1.07 g/cm2 (p<0.001); femoral BMDs 0.89 versus 0.87 (ns). CONCLUSIONS: Peri- and early postmenopausal women with a history of leiomyomas seem to have better BMD and less fractures compared with those without leiomyomas. This may be mediated through higher estrogen levels leading to higher BMD and the growth of leiomyomas. 相似文献
77.
Päivi Åstedt-Kurki PhD RN Eija Paavilainen PhD RN & Kristiina Lehti MAdSc 《Journal of advanced nursing》2001,35(2):288-293
AIM OF THE STUDY: The aim of this study is to discuss what methodological problems can be met in family research with one family member as an interviewee speaking on behalf of the whole family and, vice versa, what is the meaning of having multiple family members or the whole family unit as informants. BACKGROUND: Family nursing research is part of multidisciplinary research with families. It is a basis for family nursing and contributes to research, especially from the perspective of family welfare and its promotion. Family nursing research generates knowledge concerning families' and family members' wellbeing and experiences and expectations of nursing and health care. METHODS: The examination of methodological problems while pursuing family research is based on two studies conducted in Finland. FINDINGS: Quantitative methods add to the general knowledge of families. Qualitative methods are well suited to the study of family experiences. Family interviews performed for research purposes differ from interviews aiming at caring for families. They aim at obtaining knowledge of families on a general level so as to improve family nursing. Family research has to be looked at as a whole. It faces many challenges such as the definition of the family, gaining access, methods of data collection and data management. CONCLUSIONS: A family is a complex system and research with families need flexible, sensitive and practical methods. Family research should also aim at developing new methods for data collection and analysis. 相似文献
78.
Jenni E. Keskitalo Kaisa J. Kurkinen Mikko Neuvonen Janne T. Backman Pertti J. Neuvonen & Mikko Niemi 《British journal of clinical pharmacology》2009,68(2):207-213
AIMS
This study aimed to investigate possible effects of ABCB1 genotype on fluvastatin, pravastatin, lovastatin, and rosuvastatin pharmacokinetics.METHODS
In a fixed-order crossover study, 10 healthy volunteers with the ABCB1 c.1236C/C-c.2677G/G-c.3435C/C (CGC/CGC) genotype and 10 with the c.1236T/T-c.2677T/T-c.3435T/T (TTT/TTT) genotype ingested a single 20-mg dose of fluvastatin, pravastatin, lovastatin, and rosuvastatin. Plasma fluvastatin, pravastatin, and lovastatin concentrations were measured up to 12 h and plasma and urine rosuvastatin concentrations up to 48 and 24 h, respectively.RESULTS
The ABCB1 genotype had no significant effect on the pharmacokinetics of any of the investigated statins. The geometric mean ratio (95% confidence interval) of the area under the plasma concentration–time curve from 0 h to infinity (AUC0–∞) in participants with the TTT/TTT genotype to that in those with the CGC/CGC genotype was 0.96 (0.77, 1.20; P= 0.737) for fluvastatin, 0.92 (0.53, 1.62; P= 0.772) for pravastatin, 0.83 (0.36, 1.90; P= 0.644) for lovastatin, 1.25 (0.72, 2.17; P= 0.400) for lovastatin acid, and 1.10 (0.73, 1.65; P= 0.626) for rosuvastatin. The AUC0–∞ of lovastatin acid correlated significantly with that of rosuvastatin (r= 0.570, P= 0.009), but none of the other AUC0–∞ pairs showed a significant correlation.CONCLUSIONS
These data suggest that the ABCB1 c.1236C-c.2677G-c.3435C and c.1236T-c.2677T-c.3435T haplotypes play no significant role in the interindividual variability in the pharmacokinetics of fluvastatin, pravastatin, lovastatin, and rosuvastatin. 相似文献79.
80.
Cederqvist K Janer J Tervahartiala T Sorsa T Haglund C Salmenkivi K Stenman UH Andersson S 《Pediatric research》2006,60(4):395-400
Acute lung injury is marked by damage to alveolar-capillary barrier. High pulmonary levels of matrix-degrading serine proteinase trypsin and matrix metalloproteinases (MMP)-2, -8, and -9 have been shown in preterm infants with respiratory distress syndrome (RDS). We studied expression of trypsin and MMP-2, -8, and -9 in rats exposed to >95% oxygen for 24, 48, or 60 h. As demonstrated by zymography and Western immunoblotting, levels of trypsin and MMP-2, -8, and -9 in bronchoalveolar lavage fluid (BALF) sharply increased after 48 h of hyperoxia relative to normoxia controls. This coincided with increase in alveolar-capillary permeability, as indicated by increased protein concentration in BALF. Both neutrophil-derived 80-kD and mesenchymal cell-derived 60-kD MMP-8 isoforms were detected in BALF. Of them, mesenchymal-type MMP-8 predominated. In immunohistochemistry, alveolar epithelium showed strong trypsin expression at 48 and 60 h of hyperoxia, whereas it was predominantly negative in controls. MMP-8 was mostly expressed in macrophages. Marked up-regulation of trypsin and MMP-8 early during hyperoxic lung injury suggests that these enzymes play a role in the pathogenesis of acute lung injury and may therefore be potential targets for therapy of lung injury. 相似文献