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71.
Benjamin E. Bodnar Cassidy W. Claassen Julie Solomon Harriet Mayanja-Kizza Asghar Rastegar 《PloS one》2015,10(3)
Purpose
The MUYU Collaboration is a partnership between Mulago Hospital-Makerere University College of Health Sciences (M-MakCHS), in Kampala, Uganda, and the Yale University School of Medicine. The program allows Ugandan junior faculty to receive up to 1 year of subspecialty training within the Yale hospital system. The authors performed a qualitative study to assess the effects of this program on participants, as well as on M-MakCHS as an institution.Methods
Data was collected via semi-structured interviews with exchange participants. Eight participants (67% of those eligible as of 4/2012) completed interviews. Study authors performed data analysis using standard qualitative data analysis techniques.Results
Analysis revealed themes addressing the benefits, difficulties, and opportunities for improvement of the program. Interviewees described the main benefit of the program as its effect on their fund of knowledge. Participants also described positive effects on their clinical practice and on medical education at M-MakCHS. Most respondents cited financial issues as the primary difficulty of participation. Post-participation difficulties included resource limitations and confronting longstanding institutional and cultural habits. Suggestions for programmatic improvement included expansion of the program, ensuring appropriate management of pre-departure expectations, and refinement of program mentoring structures. Participants also voiced interest in expanding post-exchange programming to ensure both the use of and the maintenance of new capacity.Conclusions
The MUYU Collaboration has benefitted both program participants and M-MakCHS, though these benefits remain difficult to quantify. This study supports the assertion that resource-poor to resource-rich exchanges have the potential to provide significant benefits to the resource-poor partner. 相似文献72.
Vincent Kayina Samuel Kyobe Fred A. Katabazi Edgar Kigozi Moses Okee Beatrice Odongkara Harriet M. Babikako Christopher C. Whalen Moses L. Joloba Philippa M. Musoke Ezekiel Mupere 《PloS one》2015,10(4)
Background
We determined prevalence of pertussis infection and its associated host and environmental factors to generate information that would guide strategies for disease control.Methods
In a cross-sectional study, 449 children aged 3 months to 12 years with persistent cough lasting ≥14 days were enrolled and evaluated for pertussis using DNA polymerase chain reaction (PCR) and ELISA serology tests.Results
Pertussis prevalence was 67 (15% (95% Confidence Interval (CI): 12–18)) and 81 (20% (95% CI: 16–24)) by PCR and ELISA, respectively among 449 participating children. The prevalence was highest in children with >59 months of age despite high vaccination coverage of 94% in this age group. Study demographic and clinical characteristics were similar between pertussis and non-pertussis cases. Of the 449 children, 133 (30%) had a coughing household member and 316 (70%) did not. Among 133 children that had a coughing household member, sex of child, sharing bed with a coughing household member and having a coughing individual in the neighborhood were factors associated with pertussis. Children that had shared a bed with a coughing household individual had seven-fold likelihood of having pertussis compared to children that did not (odds ratio (OR) 7.16 (95% CI: 1.24–41.44)). Among the 316 children that did not have a coughing household member, age <23 months, having or contact with a coughing individual in neighborhood, a residence with one room, and having a caretaker with >40 years of age were the factors associated with pertussis. Age <23months was three times more likely to be associated with pertussis compared to age 24–59 months (OR 2.97 (95% CI: 1.07–8.28)).Conclusion
Findings suggest high prevalence of pertussis among children with persistent cough at a health facility and it was marked in children >59 months of age, suggesting the possibility of waning immunity. The factors associated with pertussis varied by presence or absence of a coughing household member. 相似文献73.
Katarina Almehed Szabolcs Hetényi Claes Ohlsson Hans Carlsten Helena Forsblad-d'Elia 《Arthritis research & therapy》2010,12(4):1-7
Introduction
The present study objective was to evaluate the incidence of methotrexate (MTX)-specific liver lesions from the analysis of a liver biopsy of inflammatory arthritis patients with elevated liver enzymes.Methods
A case-control study was performed with 1,571 arthritis patients on long-term low-dose MTX therapy. Results of liver biopsy were analyzed in 41 patients with elevated liver enzymes. The expression of autoimmune markers was also assessed. This population was compared with 41 disease control subjects obtained from the same database, also on MTX but without elevated liver enzymes, matched for age, sex and rheumatic disease.Results
Compared with the disease controls, patients with liver biopsy showed lower disease duration and lower MTX exposure, weekly and cumulative doses, reflecting shorter treatment duration due to liver abnormalities. Liver biopsies showed 17 autoimmune hepatitis-like (AIH-like) lesions, 13 nonalcoholic steatohepatitis-like lesions, seven limited liver lesions, and two primary biliary cirrhoses. However, MTX-specific lesions with dystrophic nuclei in hepatocytes were seen in only two cases. Liver biopsy lesions were associated with autoimmune markers (P = 0.007); notably, AIH-like lesions were associated with rheumatoid arthritis and with the presence of the HLA-DR shared epitope.Conclusions
MTX-specific liver lesions are rarely observed in arthritis patients under long-term MTX therapy and elevated liver enzymes. 相似文献74.
Amnon Golan Elah Pick Lyuben Tsvetkov Yasmine Nadler Harriet Kluger David F Stern 《Cell cycle (Georgetown, Tex.)》2010,9(13):2647-2656
Two major control systems regulate early stages of mitosis: activation of Cdk1 and anaphase control through assembly and disassembly of the mitotic spindle. In parallel to cell cycle progression, centrosomal duplication is regulated through proteins including Nek2. Recent studies suggest that centrosome-localized Chk1 forestalls premature activation of centrosomal Cdc25b and Cdk1 for mitotic entry, whereas Chk2 binds centrosomes and arrests mitosis only after activation by ATM and ATR in response to DNA damage. Here, we show that Chk2 centrosomal binding does not require DNA damage, but varies according to cell cycle progression. These and other data suggest a model in which binding of Chk2 to the centrosome at multiple cell cycle junctures controls co-localization of Chk2 with other cell cycle and centrosomal regulators.Key words: Chk2, centrosome, checkpoint, DNA damage, wild type, kinase-defective 相似文献
75.
B M J?nsson C L?ffler K Ohlsson 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1982,363(10):1167-1175
Two forms of urinary trypsin inhibitor, A and B, were purified from the urine of pregnant women. Form A was the only inhibitor present in fresh urine and inhibitor B arose from degradation of A upon storage of urine. The molecular masses of A and B were about 44 and 20 kDa, respectively, as judged from dodecyl-sulfate polyacrylamide gel electrophoresis, but about 60 kDa and 30 kDa, respectively, as judged from gel filtration analysis. The discrepancy can perhaps be explained by the carbohydrate content amounting to about 10% of each inhibitor. After reduction with mercaptoethanol, inhibitor A and inhibitor B had identical apparent molecular masses of about 20 kDa on dodecyl-sulfate gel electrophoresis. These results and the results of amino acid analysis suggest that one molecule of inhibitor A yields two molecules of inhibitor B. On agarose gel electrophoresis inhibitor A migrated as a rather broad band in the prealbumin region and inhibitor B as 3 well defined bands in the beta-region. Specific antisera were raised against inhibitor A and B. The two inhibitors showed the immunologic reaction of identity with each other and with the plasma inter-alpha-trypsin inhibitor, when using either antiserum. The inhibitors both gave quantitative inhibition of bovine trypsin, the results indicating a 4/1 trypsin/inhibitor molar ratio for A and a 2/1 ratio for B. The two substances also effectively inhibited granulocyte elastase. No inhibition of porcine pancreatic elastase was demonstrable. 相似文献
76.
Patty W. Siri‐Tarino Paul T. Williams Harriet S. Fernstrom Robin S. Rawlings Ronald M. Krauss 《Obesity (Silver Spring, Md.)》2009,17(9):1768-1775
Excess adiposity and high‐carbohydrate diets have been associated with an atherogenic lipoprotein phenotype (ALP) characterized by increased concentrations of small, dense low‐density lipoprotein (LDL) particles (pattern B). We tested whether weight loss and normalization of adiposity could reverse ALP in overweight men with pattern B. After consuming a moderate‐carbohydrate, high‐fat diet for 3 weeks, pattern B and nonpattern B (pattern A) men were randomized to a weight loss (n = 60 and n = 36, respectively) or control weight‐stable arm (n = 20 and n = 17, respectively). Men in the weight loss arm consumed ~1,000 fewer calories per day over 9 weeks to induce an average ~9 kg weight loss. In the control group, weight stability was maintained for 4 weeks after randomization. Weight loss led to the conversion of pattern B to pattern A in 58% of baseline pattern B men. Among men who achieved BMIs of <25 kg/m2 (62% of pattern B men vs. 83% of pattern A men), 81% of pattern B men converted to pattern A. Weight loss was associated with a significantly greater decrease in small, dense LDL subclass 3b in pattern B relative to pattern A men. The lipoprotein profiles of pattern A men who converted from pattern B were comparable to those of men with pattern A at baseline. Conversion of LDL subclass pattern B to pattern A and reversal of ALP can be achieved in a high proportion of overweight men by normalization of adiposity. 相似文献
77.
Jochems C Islander U Erlandsson M Verdrengh M Ohlsson C Carlsten H 《Arthritis research & therapy》2005,7(4):R837-R843
Generalized osteoporosis in postmenopausal rheumatoid arthritis (RA) is caused both by estrogen deficiency and by the inflammatory
disease. The relative importance of each of these factors is unknown. The aim of this study was to establish a murine model
of osteoporosis in postmenopausal RA, and to evaluate the relative importance and mechanisms of menopause and arthritis-related
osteoporosis. To mimic postmenopausal RA, DBA/1 mice were ovariectomized, followed by the induction of type II collagen-induced
arthritis. After the mice had been killed, paws were collected for histology, one femur for bone mineral density (BMD) and
sera for analyses of markers of bone resorption (RatLaps; type I collagen cross-links, bone formation (osteocalcin) and cartilage
destruction (cartilage oligomeric matrix protein), and for the evaluation of antigen-specific and innate immune responsiveness.
Ovariectomized mice displayed more severe arthritis than sham-operated controls. At termination of the experiment, arthritic
control mice and non-arthritic ovariectomized mice displayed trabecular bone losses of 26% and 22%, respectively. Ovariectomized
mice with arthritis had as much as 58% decrease in trabecular BMD. Interestingly, cortical BMD was decreased by arthritis
but was not affected by hormonal status. In addition, markers of bone resorption and cartilage destruction were increased
in arthritic mice, whereas markers of bone formation were increased in ovariectomized mice. This study demonstrates that the
loss of endogenous estrogen and inflammation contribute additively and equally to osteoporosis in experimental postmenopausal
polyarthritis. Markers of bone remodeling and bone marrow lymphocyte phenotypes indicate different mechanisms for the development
of osteoporosis caused by ovariectomy and arthritis in this model. 相似文献
78.
The activation energy for the formation of the first red compound, ES, for cytochrome-c peroxidase (ferrocytochrome-c: hydrogen-peroxide oxidoreductase, EC 1.11.1.5) by i-propyl hydroperoxide and the rate constants for the formation of ES with various hydroperoxides have been determined. Multivariate data analysis by the partial least-squares model in latent variables has been used to compare the rate constants with the corresponding rate constants for the formation of compound I from lactoperoxidase and two isoenzymes of horseradish peroxidase. The results show that the rate of formation of ES from cytochrome-c peroxidase is highly correlated with the pKa of the hydroperoxides. The activation energy for the formation of ES with i-propyl hydroperoxide is close to the corresponding value for hydrogen peroxide. 相似文献
79.
80.
Nilsson H Dragomir A Ahlander A Johannesson M Roomans GM 《Cell and tissue research》2007,330(2):257-269
Inhalation of hyperosmotic solutions (salt, mannitol) has been used in the treatment of patients with cystic fibrosis or asthma,
but the mechanism behind the effect of hyperosmotic solutions is unclear. The relation between osmolarity and permeability
changes was examined in an airway cell line by the addition of NaCl, NaBr, LiCl, mannitol, or xylitol (295–700 mOsm). Transepithelial
resistance was measured as an indicator of the tightness of the cultures. Cell-cell contacts and morphology were investigated
by immunofluorescence and by transmission electron microscopy, with lanthanum nitrate added to the luminal side of the epithelium
to investigate tight junction permeability. The electrolyte solutions caused a significant decrease in transepithelial resistance
from 450 mOsm upwards, when the hyperosmolar exposure was gradually increased from 295 to 700 mOsm; whereas the nonelectrolyte
solutions caused a decrease in transepithelial resistance from 700 mOsm upwards. Old cultures reacted in a more rigid way
compared to young cultures. Immuno-fluorescence pictures showed weaker staining for the proteins ZO-1, claudin-4, and plakoglobin
in treated samples compared to the control. The ultrastructure revealed an increased number of open tight junctions as well
as a disturbed morphology with increasing osmolarity, and electrolyte solutions opened a larger proportion of tight junctions
than nonelectrolyte solutions. This study shows that hyperosmotic solutions cause the opening of tight junctions, which may
increase the permeability of the paracellular pathway and result in increased transepithelial water transport.
This study was supported by the Swedish Asthma and Allergy Association and the Swedish Heart Lung Foundation. 相似文献