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Lawrence S Prince Heather I Dieperink Victor O Okoh German A Fierro-Perez Roger L Lallone 《Developmental dynamics》2005,233(2):553-561
We tested the hypothesis that innate immune signaling in utero could disrupt the structural development of the fetal lung, contributing to the pathogenesis of bronchopulmonary dysplasia. Injection of Escherichia coli lipopolysaccharide (LPS) into the amniotic fluid of E15 BALB/cJ mice increased the luminal volume density of fetal mouse lungs at embryonic day (E) 17 and E18. LPS also increased luminal volume and decreased distal lung branching in fetal mouse lung explants. This effect required NF-kappaB activation and functional Toll-Like Receptor 4. Airway branching may require fibronectin-dependent epithelial-mesenchymal interactions, representing a potential target for innate immune signaling. Anti-fibronectin antibodies and LPS both blocked distal lung branching. By immunofluorescence, fibronectin localized to the clefts between newly formed airways but was restricted to peripheral mesenchymal cells in LPS-exposed explants. These data suggest that LPS may alter the expression pattern of mesenchymal fibronectin, potentially disrupting epithelial-mesenchymal interactions and inhibiting distal airway branching and alveolarization. This mechanism may link innate immune signaling with defects in structural development of the fetal lung. 相似文献
24.
Birgitta Malmberg Göran Kecklund Björn Karlson Roger Persson Per Flisberg Palle Ørbaek 《BMC health services research》2010,10(1):239
Background
It is well known that physicians' night-call duty may cause impaired performance and adverse effects on subjective health, but there is limited knowledge about effects on sleep duration and recovery time. In recent years occupational stress and impaired well-being among anaesthesiologists have been frequently reported for in the scientific literature. Given their main focus on handling patients with life-threatening conditions, when on call, one might expect sleep and recovery to be negatively affected by work, especially in this specialist group. The aim of the present study was to examine whether a 16-hour night-call schedule allowed for sufficient recovery in anaesthesiologists compared with other physician specialists handling less life-threatening conditions, when on call. 相似文献25.
26.
F Reichenberger R Voswinckel B Enke M Rutsch E El Fechtali T Schmehl H Olschewski R Schermuly N Weissmann H A Ghofrani F Grimminger E Mayer W Seeger 《The European respiratory journal》2007,30(5):922-927
For chronic thromboembolic pulmonary hypertension not amenable to pulmonary endarterectomy, effective medical therapy is desired. In an open-label uncontrolled clinical trial, 104 patients (mean +/- sem age 62 +/- 11 yrs) with inoperable chronic thromboembolic pulmonary hypertension were treated with 50 mg sildenafil t.i.d. At baseline, patients had severe pulmonary hypertension (pulmonary vascular resistance 863 +/- 38 dyn.s.cm(-5)) and a 6-min walking distance of 310 +/- 11 m. Eight patients were in World Health Organization functional class II, 76 in class III and 20 in class IV. After 3 months' treatment, there was significant haemodynamic improvement, with reduction of pulmonary vascular resistance to 759 +/- 62 dyn.s.cm(-5). The 6-min walking distance increased significantly to 361 +/- 15 m after 3 months' treatment, and to 366 +/- 18 m after 12 months' treatment. A subset of 67 patients received a single dose of 50 mg sildenafil during initial right heart catheterisation. The acute haemodynamic effect of this was not predictive of long-term outcome. In this large series of patients with inoperable chronic thromboembolic pulmonary hypertension, open-label treatment with sildenafil led to significant long-term functional improvement. The acute effect of sildenafil may not predict the long-term outcome of therapy. 相似文献
27.
Michael Dietrich Christoph Meier Daniela Zeller Patrick Grueninger Roger Berbig Andreas Platz 《European journal of trauma and emergency surgery》2007,33(5):512-519
Abstract
Background: Primary shoulder hemiarthroplasty is an established treatment modality for complex fractures of the proximal humerus. Long-term
functional outcome is often disappointing. However, little is known about social implications particularly in the elderly.
Methods: A single-institution case series of consecutive geriatric patients (age > 70 years) treated with shoulder hemiarthroplasty
for complex fractures of the proximal humerus between 1994 and 1997 was analysed. Postoperative morbidity, long-term function,
radiological outcome and social implications were evaluated.
Results: Seventy-seven patients fulfilled the study criteria. Median age at the time of operation was 80 years (range 70–93 years).
Systemic and local postoperative complications were observed in 8% including 2 patients (3%) with revision surgery. Postoperative
mortality was 1%. Forty-eight patients (62%) were available for follow-up (median 49 months, range 25–80 months), 22 (29%)
died from causes unrelated to hemiarthroplasty before follow-up and 7 patients (9%) did not attend follow-up examination.
Median Constant-Murley score was 41 points (range 17–77 points). Long-term results concerning pain were satisfying. The Oxford
shoulder score ranged from 14 to 40 (median 30). Forty-one patients (85%) still lived in their original environment and managed
their daily life independently despite poor shoulder function. Four patients (8%) lived in a retirement home and 3 (6%) in
a nursery home. Eighty percent of our patients were still able to use public transportation, do the daily shopping and wash
their whole body by themselves.
Conclusion: Most patients managed their daily life independently despite poor shoulder function. 相似文献
28.
Drew T. Marshall John D. Gilbert Roger W. Byard 《Forensic science, medicine, and pathology》2007,3(1):53-55
A 26-year-old man who presented with a 2-year history of intermittent gynecomastia with recent onset of fever, night sweats,
and abdominal distension was found to have a left-sided adrenocortical carcinoma with metastases to the liver and spine. Sudden
death occurred 1 month after his presentation. At autopsy a saddle pulmonary thromboembolus was found occluding the pulmonary
outflow tract, with smaller more peripheral pulmonary thromboemboli. No tumor deposits were identified in the thromboemboli.
The thromboemboli had arisen from a tongue of tumor that had grown through the left adrenal vein into the inferior vena cava.
Despite a high rate of angio-invasion there are very few reports of sudden death resulting from this phenomenon in patients
with adrenocortical carcinoma. 相似文献
29.
E J Mayer B W Alderman J G Regensteiner J A Marshall W L Haskell J Baxter R F Hamman 《The American journal of clinical nutrition》1991,53(4):812-820
We evaluated the consistency of three questionnaire methods of assessing work and leisure activity in the rural biethnic population of the San Luis Valley Diabetes Study. A 7-d physical activity recall (PAR), a ranking of usual activity, and a history of usual participation in vigorous activity were used. Energy expenditure (kJ.kg-1.wk-1) (EE) was estimated from PAR. Subjects were 503 adults [49% non-Hispanic white (NHW), 51% Hispanic]. Physical activity at work rather than leisure-time activity largely determined total energy expenditure. Average EE at work increased with work rank for all subjects combined [mean EE (SEE) for rank 1 (low) = 324.2 (24.4), rank 4 (high) = 874.0 (102.1)] and within sex, ethnic, and occupational subgroups. Leisure EE increased with leisure rank only for NHW men and employed women. Similar patterns were observed in comparisons of PAR data with history of vigorous activity. Further development and validation of instruments appropriate for use across population subgroups are needed. 相似文献
30.
Jutta Liebau Stephanie Heidrich Alfred Berger Mayer Tenenhaus Hans-Oliver Rennekampff 《European journal of plastic surgery》2007,29(5):235-242
Re-epithelialization of cutaneous wounds is a coordinated process of proliferation and migration of keratinocytes at the wound
edge. The study objective was to identify the differences in epidermal morphology, keratinocyte proliferation and matrix molecules
(laminin 1, laminin 5, type IV collagen) and their specific integrin (α3, α6) expression in biopsies of meshed split thickness
grafted and chronic wounds. The mean mitotic index of keratinocytes (ratio of cell cycle associated antigen Ki-67 expressing
keratinocytes to basal keratinocytes) was highest in chronic wounds (38.7%) compared to acute wounds (22.25%, range 5.7% to
54%). The mean thickness of the hyper-proliferative epithelium at the wound edge of chronic wounds was 0.69 mm compared to
0.15 mm at the wound margin of split thickness grafted wounds. Both chronic wounds and skin grafted wounds exhibited strong
laminin 5 immunoreactivity at the basal side of the epithelium, which extended under the most forward keratinocytes. Laminin
1 and type IV collagen immunoreactivity did not extend to the wound margin in either skin grafted or chronic wounds. In both
transplanted skin and chronic wounds, the integrin sub-units α3 and α6 exhibited a strong pericellular immunoreactivity on
the leading keratinocytes of the wound margin. Our data demonstrates that the proliferation of keratinocytes and the expression
of associated integrins are not impaired in chronic wounds.
Presented at the 33rd Congress of the Association of German Plastic Surgeons, Germany, 18–21 September, 2002. 相似文献