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1.
The content of alkaline phosphatase (ALP) was determined in neutrophils isolated from patients with acute bacterial infections by a standard enzyme assay. Compared with control cells, patient cells exhibited about a fivefold increase in ALP activity. There was no difference between the ALP Km values of control and patient cells, which indicates that the elevated activity in patient cells was due to the presence of increased amounts of the enzyme. The ALP isozyme in both cell types was determined to be the tissue-unspecific ALP. The fact that much of the ALP activity was measurable only in the presence of detergent suggested that the enzyme was localized in the secretory vesicles, a putative reservoir of plasma membrane components. The amount and subcellular distribution of two other secretory vesicle membrane proteins, i.e., cytochrome b and complement receptor 3, were not altered; hence, we conclude that there was no general increase in amounts of secretory vesicle membrane constituents in the patient cells.  相似文献   
2.
Sensory information continuously converges on the spinal cord during a variety of motor behaviours. Here, we examined presynaptic control of group Ia afferents in relation to acquisition of a novel motor skill. We tested whether repetition of two motor tasks with different degrees of difficulty, a novel visuo-motor task involving the ankle muscles, and a control task involving simple voluntary ankle movements, would induce changes in the size of the soleus H-reflex. The slope of the H-reflex recruitment curve and the H-max/M-max ratio were depressed after repetition of the visuo-motor skill task and returned to baseline after 10 min. No changes were observed after the control task. To elucidate the mechanisms contributing to the H-reflex depression, we measured the size of the long-latency depression of the soleus H-reflex evoked by peroneal nerve stimulation (D1 inhibition) and the size of the monosynaptic Ia facilitation of the soleus H-reflex evoked by femoral nerve stimulation. The D1 inhibition was increased and the femoral nerve facilitation was decreased following the visuo-motor skill task, suggesting an increase in presynaptic inhibition of Ia afferents. No changes were observed in the disynaptic reciprocal Ia inhibition. Somatosensory evoked potentials (SEPs) evoked by stimulation of the tibial nerve (TN) were also unchanged, suggesting that transmission in ascending pathways was unaltered following the visuo-motor skill task. Together these observations suggest that a selective presynaptic control of Ia afferents contributes to the modulation of sensory inputs during acquisition of a novel visuo-motor skill in healthy humans.  相似文献   
3.
PURPOSE: The causes, prevention, and treatment of osteoporosis in specific populations are discussed. SUMMARY: Osteoporosis and osteopenia affect 44 million women and men ages 50 years or older. Fractures are the most devastating consequence of this disease and significantly affect quality of life, activities of daily living, survival, and health care costs. Most osteoporosis research has focused on postmenopausal women, but several other populations are at risk for osteoporosis, such as patients taking certain medications that affect bone health and those with various health conditions that cause bone loss, including anorexia nervosa, hyperthyroidism, organ transplantation, chronic obstructive pulmonary disease, and inflammatory bowel disease. Glucocorticoids are the most common secondary cause of osteoporosis. Other medications that have been implicated as secondary causes include anticonvulsants, heparin, warfarin, and methotrexate. Preventing osteoporosis may be even more important in adolescence than after menopause. CONCLUSION: Osteoporosis needs to be recognized, monitored, and appropriately treated in patients taking medications that affect bone health and in patients with conditions that increase the risk of osteoporosis.  相似文献   
4.
Rapid screening of methicillin‐resistant Staphylococcus aureus (MRSA) colonization prior to hospital admittance is important to reduce nosocomial infections and health care costs. Molecular detection of mecA and S. aureus specific target genes has become widely established for this purpose. However, there are still limitations in potential for high‐throughput screening in the methods described. We have compared the time aspects and workload of four different DNA preparation platforms, resulting in an automated and simple MRSA screening method which combines two liquid handling systems and a simple lysis buffer. We have further transferred our in‐house dual real‐time PCR to a fast‐PCR protocol, reducing the time and labour spent on these samples to a minimum.  相似文献   
5.
In vitro expanded adipose-derived stromal cells (ASCs) are a useful resource for tissue regeneration. Translation of small-scale autologous cell production into a large-scale, allogeneic production process for clinical applications necessitates well-chosen raw materials and cell culture platform. We compare the use of clinical-grade human platelet lysate (hPL) and fetal bovine serum (FBS) as growth supplements for ASC expansion in the automated, closed hollow fibre quantum cell expansion system (bioreactor). Stromal vascular fractions were isolated from human subcutaneous abdominal fat. In average, 95?×?106 cells were suspended in 10% FBS or 5% hPL medium, and loaded into a bioreactor coated with cryoprecipitate. ASCs (P0) were harvested, and 30?×?106 ASCs were reloaded for continued expansion (P1). Feeding rate and time of harvest was guided by metabolic monitoring. Viability, sterility, purity, differentiation capacity, and genomic stability of ASCs P1 were determined. Cultivation of SVF in hPL medium for in average nine days, yielded 546?×?106 ASCs compared to 111?×?106 ASCs, after 17?days in FBS medium. ASCs P1 yields were in average 605?×?106 ASCs (PD [population doublings]: 4.65) after six days in hPL medium, compared to 119?×?106 ASCs (PD: 2.45) in FBS medium, after 21?days. ASCs fulfilled ISCT criteria and demonstrated genomic stability and sterility. The use of hPL as a growth supplement for ASCs expansion in the quantum cell expansion system provides an efficient expansion process compared to the use of FBS, while maintaining cell quality appropriate for clinical use. The described process is an obvious choice for manufacturing of large-scale allogeneic ASC products.  相似文献   
6.
International Journal of Clinical Pharmacy - In recent years, increased longevity of the Danish population has resulted in a growing segment with age-related and chronic health conditions. This,...  相似文献   
7.
8.
Ficolin-2 is a serum opsonin, which has been shown to be a pattern recognition molecule in the lectin complement activation pathway. Because innate immune mechanisms are involved in maintaining tissue homeostasis we hypothesized that Ficolin-2 also participate in the clearance of dying host cells. We found that Ficolin-2 binds to late apoptotic cells, as well as to apoptotic bodies and necrotic cells, but not to early apoptotic cells. We demonstrated that Ficolin-2 binds DNA in a calcium dependent manner and that DNA inhibits the binding to late apoptotic and necrotic cells, suggesting that DNA on permeable dying cells is a plausible ligand. Reconstituting serum deficient of Ficolin-2, C1q and mannose-binding lectin with Ficolin-2 augmented deposition of complement C4 on necrotic cells. Opsonization leads to an enhanced attachment/uptake of necrotic cells by macrophages. In conclusion dying host cells expose ligands with the capacity of binding Ficolin-2, which in turn leads to increased attachment and engulfment. Binding of Ficolin-2 to DNA points at nucleic acid exposed by permeable late apoptotic and necrotic cells as one of the ligands for Ficolin-2. Ficolin-2 may therefore be a scavenger molecule participating in the removal of host cells and maintenance of tissue homeostasis.  相似文献   
9.

Objectives

Intervention studies of clavicle fracture treatment are numerous, but only a few high quality studies prospectively compare operative and nonoperative treatment. The objective of this study was to review evidence from randomized controlled trials on operative versus nonoperative treatment of displaced midshaft clavicle fractures in adults with focus on fracture healing, complications and functional outcome.

Data sources

An electronic search was performed of PubMed, Embase and Cochrane databases which revealed 559 articles. All articles published before October 18th 2012 and written in English, Danish or Swedish were eligible.

Study selection

Articles were excluded if they included children under the age of 16, did not include acute midshaft fractures, included concomitant fractures, did not meet the requirements of Level I evidence according to Centre for evidence based medicine 2009 guidelines, were systematic reviews or meta-analyses, or did not compare operative and nonoperative treatment.

Data extraction

Articles were parsed for relevance by two reviewers independently regarding title, abstract, and full text. Extraction of data was done by both reviewers in collaboration and sorted according to the aims of the study. Complications were grouped according to additional surgery required. The quality of studies was assessed by both reviewers in unison using Critical Appraisal Skills Programme 2010 checklists.

Conclusions

It seems like operative intervention leads to fewer nonunions at the cost of an increase in minor complications compared to nonoperative treatment. However, the effects of operation on functional outcome remains controversial. High quality evidence is currently sparse supporting either operative or nonoperative treatment on displaced midshaft clavicle fractures in adults.  相似文献   
10.
To investigate the management of patients with community-acquired pneumonia (CAP) treated in hospital in Sweden, a multicentre retrospective cohort study was performed with medical record review of 982 patients (mean age 63 y) at 17 departments of infectious diseases at hospitals in Sweden. Information on antimicrobial therapy, demographic characteristics, comorbid conditions, physical examination findings, and laboratory and microbiological test results were recorded. Outcome measures were in-hospital mortality and length of hospital stay (LOS). Cultures were obtained from blood in 80% and from sputum in 22% of the patients. A microbiological aetiology was determined for 23% of the patients, with Streptococcus pneumoniae as the dominating agent (9%). The initial antibiotic treatment was mostly given intravenously (78%). Penicillin (50%) or a cephalosporin (30%) was the most common choice. Both of these drugs were usually given as a single agent. The overall mortality was 3.5% and the mean LOS was 6.4 d. Thus, the outcome was favourable despite the empirical antibiotic treatment having a narrow spectrum compared with the broader approach recommended in most recent guidelines on the management of CAP. These findings suggest that a majority of patients who are hospitalized with moderately severe pneumonia can be treated initially with penicillin alone.  相似文献   
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