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41.
Sequential activation of microglia and astrocyte cytokine expression precedes increased iba‐1 or GFAP immunoreactivity following systemic immune challenge 下载免费PDF全文
Activation of the peripheral immune system elicits a coordinated response from the central nervous system. Key to this immune to brain communication is that glia, microglia, and astrocytes, interpret and propagate inflammatory signals in the brain that influence physiological and behavioral responses. One issue in glial biology is that morphological analysis alone is used to report on glial activation state. Therefore, our objective was to compare behavioral responses after in vivo immune (lipopolysaccharide, LPS) challenge to glial specific mRNA and morphological profiles. Here, LPS challenge induced an immediate but transient sickness response with decreased locomotion and social interaction. Corresponding with active sickness behavior (2–12 h), inflammatory cytokine mRNA expression was elevated in enriched microglia and astrocytes. Although proinflammatory cytokine expression in microglia peaked 2‐4 h after LPS, astrocyte cytokine, and chemokine induction was delayed and peaked at 12 h. Morphological alterations in microglia (Iba‐1+) and astrocytes (GFAP+), however, were undetected during this 2–12 h timeframe. Increased Iba‐1 immunoreactivity and de‐ramified microglia were evident 24 and 48 h after LPS but corresponded to the resolution phase of activation. Morphological alterations in astrocytes were undetected after LPS. Additionally, glial cytokine expression did not correlate with morphology after four repeated LPS injections. In fact, repeated LPS challenge was associated with immune and behavioral tolerance and a less inflammatory microglial profile compared with acute LPS challenge. Overall, induction of glial cytokine expression was sequential, aligned with active sickness behavior, and preceded increased Iba‐1 or GFAP immunoreactivity after LPS challenge. GLIA 2016;64:300–316 相似文献
42.
Muscle strength and soccer practice as major determinants of bone mineral density in adolescents 总被引:1,自引:0,他引:1
Seabra A Marques E Brito J Krustrup P Abreu S Oliveira J Rêgo C Mota J Rebelo A 《Joint, bone, spine : revue du rhumatisme》2012,79(4):403-408
ObjectivesTo analyse the relationship between isokinetic strength of the lower limb muscles and bone mineral density and content (BMD, BMC) of adolescent male soccer players and age-matched controls not involved in sport (12–15 years).MethodsA random sample of 151 young males was divided into soccer players (SG; n = 117) and control subjects (CG; n = 34). Peak torque of knee extensors (PTE) and flexors (PTF) was measured during isokinetic knee joint movement (90°/s) of the dominant and non-dominant lower limbs. BMD and BMC of the whole-body, lumbar spine, dominant/non-dominant lower limb were determined by dual-energy X-ray absorptiometry. Physical activity was monitored with accelerometers during 5 days. Estimated maturity offset was used as an indicator of biological maturity status.ResultsWhole-body BMD (1.03 ± 0.01 vs. 0.98 ± 0.01 g/cm2, P = 0.003) and dominant (1.09 ± 0.01 vs. 1.02 ± 0.01 g/cm2, P < 0.001) and non-dominant (1.09 ± 0.01 vs. 1.01 ± 0.01 g/cm2, P < 0.001) lower limb BMD was greater in SG compared to CG. No significant differences were found for BMC. Compared to CG, SG performed better in the YY-IE2 test (780 ± 40 vs. 625 ± 31 m), exhibited higher PTE (dominant limb: 155.2 ± 30.3 vs. 123.4 ± 37.0 N m; non-dominant limb: 156.2 ± 36.1 vs. 120.4 ± 41.1 N m) and PTF muscles (dominant limb: 79.0 ± 25.3 vs. 57.1 ± 25.3 Nm; non-dominant limb: 73.3 ± 20.7 vs. 57.0 ± 24.2 N m). Moreover, the PTE, soccer participation and maturity status were positively associated with the BMD at all body sites (r2 = 0.57–0.73, P < 0.05).ConclusionsMuscle strength of knee extensors is associated with BMD and BMC at all body sites. Muscle-skeletal structures respond positively to the weight-bearing and impact-loading imposed by soccer practice. Soccer seemed to be a multilateral balanced sport activity. 相似文献
43.
Prowle JR Calzavacca P Licari E Ligabo EV Echeverri JE Haase M Haase-Fielitz A Bagshaw SM Devarajan P Bellomo R 《Nephrology (Carlton, Vic.)》2012,17(3):215-224
Aim: To test whether short‐term perioperative administration of oral atorvastatin could reduce incidence of postoperative acute kidney injury (AKI) in cardiac surgical patients. Methods: We conducted a double‐blind, randomized controlled trial in 100 cardiac surgical patients at increased risk of postoperative AKI. Patients were randomized to atorvastatin (40 mg once daily for 4 days starting preoperatively) or identical placebo capsule. Primary outcome was to detect a smaller absolute rise in postoperative creatinine with statin therapy. Secondary outcomes included AKI defined by the creatinine criteria of RIFLE consensus classification (RIFLE R, I or F), change in urinary neutrophil gelatinase‐associated lipocalin (NGAL) concentration, requirement for renal replacement therapy, length of stay in intensive care, length of stay in hospital and hospital mortality. Results: Study groups were well matched. For each patient maximal increase in creatinine during the 5 days after surgery was assessed; median maximal increase was 28 µmol/L in the atorvastatin group and 29.5 µmol/L in the placebo group (P = 0.62). RIFLE R or greater occurred in 26% of patients with atorvastatin and 32% with placebo (P = 0.65). Postoperatively urine NGAL changes were similar (median NGAL : creatinine ratio at intensive care unit admission: atorvastatin group 1503 ng/mg, placebo group 1101 ng/mg; P = 0.22). Treatment was well tolerated and adverse events were similar between groups. Conclusion: Short‐term perioperative atorvastatin use was not associated with a reduced incidence of postoperative AKI or smaller increases in urinary NGAL. (ClinicalTrials.gov NCT00910221). 相似文献
44.
Brown JA Min J Staropoli JF Collin E Bi S Feng X Barone R Cao Y O'Malley L Xin W Mullen TE Sims KB 《Amyotrophic lateral sclerosis》2012,13(2):217-222
SOD1, ANG, TARDBP and FUS mutations have been associated with amyotrophic lateral sclerosis (ALS). Our goal was to extend molecular genetic analysis to newly identified ALS genetic loci and to determine the frequency of mutations, distribution of disease genes, and variant spectrum of these genes in a large United States ALS-phenotype cohort. We screened 1220 probands with an ALS phenotype, referred originally for SOD1 molecular genetic analysis. 1128 SOD1-negative probands were screened for ANG, and 277 and 223 SOD1- and ANG-negative samples were screened for TARDBP and FUS, respectively. One hundred additional probands were specifically screened only for FUS exon 15. We identified a total of 36 different SOD1 mutations, including three novel mutations, in 92 probands. ANG screening identified three mutations, including two novel mutations, and TARDBP screening identified two previously reported TARDBP mutations. We also identified four mutations in FUS, including the reported FUS in-frame deletion, c.430_447del, p.Gly144_Tyr149del, in a patient with inclusion body myositis, and two known FUS missense mutations. From this study, we estimate frequencies for SOD1, ANG, TARDBP and FUS mutations, in this United States cohort, to be 7.5%, 0.71%, 0.72% and 1.9%, respectively. In conclusion, we identify novel variants in SOD1, ANG, TARDBP and FUS, and expand the FUS-associated clinicopathologic phenotype. 相似文献
45.
Eller-Vainicher C Morelli V Ulivieri FM Palmieri S Zhukouskaya VV Cairoli E Pino R Naccarato A Scillitani A Beck-Peccoz P Chiodini I 《Journal of bone and mineral research》2012,27(10):2223-2230
Patients with adrenal incidentalomas (AIs) and subclinical hypercortisolism (SH) have increased risk of fracture independent of bone mineral density (BMD) and possibly due to reduced bone quality. The trabecular bone score (TBS) has been proposed as a index of bone microarchitecture. The aim of the study was to investigate TBS in AI. In 102 AI patients, SH was diagnosed in the presence of at least two of the following: (1) urinary free cortisol >70 µg/24 h (193.1 nmol/L); (2) cortisol after 1‐mg dexamethasone suppression test (1‐mg DST) >3.0 µg/dL (82.8 nmol/L); or (3) adrenocorticotropic hormone (ACTH) <10 pg/mL (<2.2 pmol/L). In patients and in 70 matched controls, BMD was measured at lumbar spine (LS) and femur (neck [FN] and total [FT]) by dual X‐ray absorptiometry and TBS was assessed in the region of LS‐BMD; BMD and TBS data were reported as Z‐scores. In patients, vertebral deformities were assessed by radiograph. Patients with SH (n = 34) had lower LS‐BMD (?0.31 ± 1.17), FT‐BMD (?0.29 ± 0.91), and TBS (?3.18 ± 1.21) than patients without SH (n = 68, 0.31 ± 1.42, p = 0.03; 0.19 ± 0.97, p = 0.01; ?1.70 ± 1.54, p < 0.0001, respectively) and controls (0.42 ± 1.52, p = 0.02; 0.14 ± 0.76, p = 0.02; ?1.19 ± 0.99, p < 0.0001, respectively). TBS was inversely correlated with 1‐mg DST (β = ?0.26, t = ?2.79, p = 0.006) regardless of age, LS‐BMD, body mass index (BMI), and gender. The presence of fracture was associated with low TBS alone (odds ratio [OR], 4.8; 95% confidence interval [CI], 1.85–12.42, p = 0.001) and with the cluster low TBS plus low LS‐BMD (OR, 4.37; 95% CI, 1.71–11.4, p = 0.002), after adjustment for age, BMI, and gender. Low TBS plus low LS‐BMD showed a good specificity (79%) for predicting fractures, whereas normal TBS (ie, > ?1.5) plus normal LS‐BMD high specificity (88.1%) for excluding fractures. Finally, TBS predicted the occurrence of a new fracture in 40 patients followed for 24 months (OR, 11.2; 95%CI, 1.71–71.41, p = 0.012) regardless of LS‐BMD, BMI, and age. In SH, bone quality, as measured by TBS, is altered. TBS is useful in detecting AI patients at risk of fractures. © 2012 American Society for Bone and Mineral Research. 相似文献
46.
Uberto Fumagalli Riccardo Rosati Stefano De Pascale Matteo Porta Elisa Carlani Alessandra Pestalozza Alessandro Repici 《Journal of gastrointestinal surgery》2016,20(3):494-499
Aim
Surgical myotomy of the lower esophageal sphincter has a 5-year success rate of approximately 91 %. Peroral endoscopic myotomy can provide similar results for controlling dysphagia. Some patients experience either persistent or recurrent dysphagia after myotomy. We present here a retrospective analysis of our experience with redo myotomy for recurrent dysphagia in patients with achalasia.Methods
From March 1996 to February 2015, 234 myotomies for primary or recurrent achalasia were performed in our center. Fifteen patients (6.4 %) had had a previous myotomy and were undergoing surgical redo myotomy (n?=?9) or endoscopic redo myotomy (n?=?6) for recurrent symptoms.Results
Patients presented at a median of 10.4 months after previous myotomy. Median preoperative Eckardt score was 6. Among the nine patients undergoing surgical myotomy, three esophageal perforations occurred intraoperatively (all repaired immediately). Surgery lasted 111 and 62 min on average (median) in the surgical and peroral endoscopic myotomy (POEM) groups, respectively. No postoperative complications occurred in either group. Median postoperative stay was 3 and 2.5 days in the surgical and POEM groups, respectively. In the surgical group, Eckardt score was <3 for seven out of nine patients after a mean follow-up of 19 months; it was <3 for all six patients in the POEM group after a mean follow-up of 5 months.Conclusions
A redo myotomy should be considered in patients who underwent myotomy for achalasia and presenting with recurrent dysphagia. Preliminary results using POEM indicate that the technique can be safely used in patients who have undergone previous surgical myotomy.47.
Continuous Metabolic Monitoring in Infant Cardiac Surgery: Toward an Individualized Cardiopulmonary Bypass Strategy 下载免费PDF全文
Salvatore Torre Elisa Biondani Tiziano Menon Diego Marchi Mauro Franzoi Daniele Ferrarini Rocco Tabbì Stiljan Hoxha Luca Barozzi Giuseppe Faggian Giovanni Battista Luciani 《Artificial organs》2016,40(1):65-72
Cardiopulmonary bypass (CPB) in infants is associated with morbidity due to systemic inflammatory response syndrome (SIRS). Strategies to mitigate SIRS include management of perfusion temperature, hemodilution, circuit miniaturization, and biocompatibility. Traditionally, perfusion parameters have been based on body weight. However, intraoperative monitoring of systemic and cerebral metabolic parameters suggest that often, nominal CPB flows may be overestimated. The aim of the study was to assess the safety and efficacy of continuous metabolic monitoring to manage CPB in infants during open‐heart repair. Between December 2013 and October 2014, 31 consecutive neonates, infants, and young children undergoing surgery using normothermic CPB were enrolled. There were 18 male and 13 female infants, aged 1.4 ± 1.7 years, with a mean body weight of 7.8 ± 3.8 kg and body surface area of 0.39 m2. The study was divided into two phases: (i) safety assessment; the first 20 patients were managed according to conventional CPB flows (150 mL/min/kg), except for a 20‐min test during which CPB was adjusted to the minimum flow to maintain MVO2 >70% and rSO2 >45% (group A); (ii) efficacy assessment; the following 11 patients were exclusively managed adjusting flows to maintain MVO2 >70% and rSO2 >45% for the entire duration of CPB (group B). Hemodynamic, metabolic, and clinical variables were compared within and between patient groups. Demographic variables were comparable in the two groups. In group A, the 20‐min test allowed reduction of CPB flows greater than 10%, with no impact on pH, blood gas exchange, and lactate. In group B, metabolic monitoring resulted in no significant variation of endpoint parameters, when compared with group A patients (standard CPB), except for a 10% reduction of nominal flows. There was no mortality and no neurologic morbidity in either group. Morbidity was comparable in the two groups, including: inotropic and/or mechanical circulatory support (8 vs. 1, group A vs. B, P = 0.07), reexploration for bleeding (1 vs. none, P = not significant [NS]), renal failure requiring dialysis (none vs. 1, P = NS), prolonged ventilation (9 vs. 4, P = NS), and sepsis (2 vs. 1, P = NS). The present study shows that normothermic CPB in neonates, infants, and young children can be safely managed exclusively by systemic and cerebral metabolic monitoring. This strategy allows reduction of at least 10% of predicted CPB flows under normothermia and may lay the ground for further tailoring of CPB parameters to individual patient needs. 相似文献
48.
Teresa Calabró Rupert Van Rooyen Ilaria Piraino Elisa Pala Giulia Trovarelli Georgios N. Panagopoulos Panayiotis D. Megaloikonomos Andrea Angelini Andreas F. Mavrogenis Pietro Ruggieri 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2016,26(4):415-421
Background
Various megaprostheses are currently available for reconstruction of the proximal femur after tumor resection. This study evaluates the survival and complications of a modular megaprosthesis for reconstruction of the proximal femur.Materials and methods
We studied the medical files of 109 tumor patients (age range 16–86 years) who underwent proximal femoral reconstruction with the MRP® megaprosthesis from 2002 to 2011. There were 70 patients with metastases, 34 patients with bone sarcomas, and five patients with hematological malignancies; 82 were primary and 27 were revision reconstructions. Mean follow-up was 2.5 years; 31 patients had a minimum five-year follow-up. We evaluated the survival and function of the patients, and the survival and complications of the megaprostheses.Results
Survival was significantly higher for the patients with bone sarcomas compared to those with metastases and hematological malignancies. Mean MSTS functional score was similar between patients with bone sarcomas and those with hematological malignancies and metastases, and between patients with primary and those with revision reconstructions. Overall survival of the MRP® megaprostheses was 74 % at 5 and 9 years. Fourteen (13.6 %) major complications occurred at a mean period of 1.4 years (range 3 months to 4.5 years); these included infection (5.8 %), dislocation (3.9 %), local recurrence (2.9 %), and acetabular fracture (1 %).Conclusion
MRP® megaprostheses are a valuable reconstruction option after tumor resection of the proximal femur.49.
Amer K. Karam MD Meier Hsu MS Sujata Patil PhD Michelle Stempel MS Tiffany A. Traina MD Alice Y. Ho MD Hiram S. Cody MD Elisa R. Port MD Monica Morrow MD Mary L. Gemignani MD MPH 《Annals of surgical oncology》2009,16(7):1952-1958
Background Completion axillary lymph node dissection (CALND) is routinely performed in breast cancer patients with positive sentinel
lymph nodes (SLN). We sought to determine the sociodemographic, pathologic, and therapeutic variables that were associated
with CALND.
Methods From 7/1997 to 7/2003, 1,470 patients with invasive breast cancer were SLN positive by intraoperative frozen section or final
pathologic exam by hematoxylin–eosin and/or immunohistochemistry (IHC). A comorbidity score was assigned using Adult Comorbidity
Evaluation-27 system. Fisher’s exact, Wilcoxon tests, and multivariate logistic regression analysis were used.
Results CALND was performed less often in patients with age ≥ 70 years compared with age < 70 years, moderate or severe comorbidities
compared with no or mild, IHC-only positive SLN and breast conservation therapy (BCT compared with mastectomy. Patients who
did not undergo CALND were less likely than CALND patients to have grade III disease, lymphovascular invasion multifocal disease,
tumor size > 2 cm or to receive adjuvant chemotherapy. However, they were more likely to undergo axillary radiotherapy (RT).
On multivariate analysis, age ≥ 70 years [odds ratio (OR) 0.4, 95% confidence interval (CI) 0.26–0.63], IHC-only positive
SLN (OR 0.13, 95%CI 0.09–0.19), presence of moderate to severe comorbidities (OR 0.64, 95%CI 0.41–0.99), tumor size ≤ 2 cm
(OR 0.44, 95%CI 0.29–0.66), axillary RT (OR 0.39, 95%CI 0.20–0.78), and BCT (OR 0.54, 95%CI 0.37–0.79) were all independently
associated with lower odds of CALND.
Conclusions The decision to perform CALND following positive SLN biopsy was multifactorial. Patient factors were a primary determinant
for the use of CALND in our study. The decreased use of CALND in the BCT patients probably reflects reliance on the radiotherapy
tangents to maintain local control in the axilla. 相似文献
50.