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21.

Objective

An experimental model of severe injury with great lethality was studied to define the impact of bacterial translocation on survival and on inflammatory response.

Methods

Forty-one rabbits were divided into two groups: A, femur myotomy; and B, myotomy and fracture of the femoral bone. Vital signs and survival were recorded. Serum circulating endotoxins (lipopolysaccharides; LPS) were determined and tissue cultures were performed at necropsy. A subgroup of animals was sacrificed at 48 h post injury; LPS was determined in abdominal aorta and portal vein, apoptosis of spleen cells was assessed by flow cytometry, and ex vivo production of tumor necrosis factor alpha by splenocytes was measured.

Results

Tissue bacterial burden was increased in animals that died early (i.e., within 48 h after injury) versus rabbits that died later. Portal vein LPS at 48 h was increased in group B compared with group A, whereas circulating LPS did not differ. No difference in apoptosis of either lymphocytes or macrophages of the spleen was found in group B compared with group A. Following stimulation with LPS or phytohemagglutinin, tumor necrosis factor α production by splenocytes of group B was greater than that of group A.

Conclusions

Bacterial translocation primes enhanced proinflammatory responses and it is associated with early death in severe trauma.  相似文献   
22.
23.

Purpose

To evaluate the effect of vardenafil on renal function after renal ischemia–reperfusion (IR) injury (IRI) in a rat model.

Materials and methods

Seventy-one Wistar rats were divided into 7 groups including (1) a vehicle-treated group, (2) a vehicle pretreated-IR group, (3–6) vardenafil pretreated-IR groups in doses of 0.02, 0.2, 2 and 20 μg/kg, respectively, (7) a group of IR followed by treatment with 2 μg/kg of vardenafil. Vardenafil or vehicle solution was administered one hour before unilateral nephrectomy and the induction of 45 min of ischemia on the contralateral kidney by clamping of renal pedicle. Four hours of reperfusion were allowed after renal ischemia. Studied parameters were serum creatinine, fractional excretion of sodium (FENa), and histological evaluation of renal specimens. In addition, renal tissue cGMP levels, ERK1/2 phosphorylation as well as renal function by renal scintigraphy were also evaluated.

Results

Administration of vardenafil before the induction of ischemia resulted in a significant reduction in creatinine and FENa levels as well as in less histological lesions observed in treated kidneys in comparison with the vehicle-treated group. The underlying mechanism of cytoprotection was cGMP depended and involved the phosphorylation of ERK proteins. Renal scintigraphy confirmed that PDE5 inhibition attenuates renal IRI.

Conclusions

Vardenafil attenuates renal IRI. Based on similar results from relevant studies on other PDE-5 inhibitors in renal and cardiac IRI, it can be assumed that all PDE-5 inhibitors share a common mechanism of cytoprotection.  相似文献   
24.
INTRODUCTIONHemangiopericytoma (HPC)/solitary fibrous tumor (SFT) is a very uncommon tumor of uncertain malignant behavior. In 1942, Stout and Murray first characterized these neoplasms as “vascular tumors arising from Zimmerman's pericytes” and till now hemangiopericytomas and solitary fibrous tumors of the soft tissues are regarded as features of the same entity in the soft tissue fascicle.PRESENTATION OF CASEWe present a case of hemangiopericytoma/solitary fibrous tumor of the pectoralis major muscle in a 33-year-old female. She first noticed a painless mass in her right breast. Ultrasound of the breast revealed a large heterogeneously hypoechoic lesion within the pectoralis major muscle. Fine needle aspiration of the tumor did not produce any meaningful result. The lesion was completely removed by surgical resection. Histologically, the tumor had staghorn-like vasculature and immunohistochemistry for CD34 was positive, whereas desmin, smooth-muscle actin, S-100 protein, cytokeratins (AE1/AE3) and epithelial membrane antigen (EMA) were all negative. A diagnosis of hemangiopericytoma/solitary fibrous tumor was rendered.DISCUSSIONTumors comprising the HPC/SFT spectrum represent a small subset of soft tissue sarcomas and are found virtually at any site in the body. Wide surgical resection can achieve favorable long-term survival.CONCLUSIONDue to the rarity and unpredictable biological potential of these tumors, long-term follow-up is mandatory even after radical resection, because recurrence or development of metastasis may be delayed many years.  相似文献   
25.
We have generated three monoclonal cell‐penetrating antibodies (CPAbs) from a non‐immunized lupus‐prone (NZB × NZW)F1 mouse that exhibited high anti‐DNA serum titres. These CPAbs are polyreactive because they bind to DNA and other cellular components, and localize mainly in the nucleus of HeLa cells, albeit with a distinct nuclear labelling profile. Herein, we have examined whether DNA–histone complexes (DHC) binding to CPAbs, before cell entry, could modify the cell penetration of CPAbs or their nuclear staining properties. By applying confocal microscopy and image analysis, we found that extracellular binding of purified CPAbs to DHC significantly enhanced their subsequent cell‐entry, both in terms of percentages of positively labelled cells and fluorescence intensity (internalized CPAb amount), whereas there was a variable effect on their nuclear staining profile. Internalization of CPAbs, either alone or bound to DHC, remained unaltered after the addition of endocytosis‐specific inhibitors at 37° or assay performance at 4°, suggesting the involvement of energy‐independent mechanisms in the internalization process. These findings assign to CPAbs a more complex pathogenetic role in systemic lupus erythematosus where both CPAbs and nuclear components are abundant.  相似文献   
26.

Aim

To assess the changes in health-related quality of life in patients discharged from the intensive care unit (ICU).

Methods

At the General University ICU, Trauma Hospital in Athens, 242 patients were enrolled prospectively over a study period of 18 months. Out of these, 116 participants (47.9%) completed all survey components at 6, 12, and 18 months. We used Quality of Life-Spanish (QOL-SP) to assess the health-related quality of life. Patients or their relatives were interviewed on ICU admission and at 6, 12, and 18 months after discharge from the ICU.

Results

Mean quality of life score of the patients increased from 2.9 ± 4.8 (out of maximum 25 points) on ICU admission to 7.0 ± 7.2 points at 6 months after discharge, and then decreased to 5.6 ± 6.9 points at 18 months (P<0.001; Friedman test). Multilinear regression analysis showed that the variables which had the strongest association with the quality of life on admission were age (P = 0.002) and male sex (P = 0.001), whereas age (P<0.001), length of ICU stay (P<0.001), and male sex (P = 0.002) had the strongest association 18 months after discharge from the ICU. Survival rate was 66.9% at discharge from ICU and 61.6% at hospital discharge. There were 33% deaths in the ICU, 5.3% in the hospital, and 6.2% after ICU discharge. There were 7.4% patients lost to follow-up.

Conclusions

After discharge from the ICU, patients’ quality of life was poor and showed an improvement at 18 months after discharge, but was still worse than on admission. Age, ICU length of stay, and male sex were the factors that had the strongest impact on the quality of life on admission and at 18 months after discharge from the ICU.The cost of intensive care and limited resources directed to patients with a poor prognosis raise questions about the utilization of such resources. Since the need for intensive care in several countries exceeds its availability (1), intensive care specialists are forced to admit those patients who will benefit most. There is an increasing pressure that the assessment of long-term survival and quality of life of survivors should be incorporated into outcome evaluation of intensive care unit (ICU) (2).Instruments for assessing quality of life in critically ill patients surviving intensive care include EuroQol-5D (EQ-5D), Nottingham Health Profile (NHP), Sickness Impact Profile (SIP), Medical Outcomes Study 36-item Short Form (SF-36), and Quality Of Life-Spanish (QOL-SP) (3). These instruments aim to evaluate the aspects of health important for all patients. Several cross-sectional studies have used generic, multidimensional quality of life instruments to compare health-related quality of life of intensive care patients with the that of the general population and found a considerable deterioration in the former group (3,4). However, such evidence may be misleading if pre-hospitalization health-related quality of life is not taken into account.Quality of life is an important endpoint in assessing long-term results of intensive care, but the ideal timing for such an assessment is still unclear. This topic has been covered in some reports dealing with pre-ICU assessment of health-related quality of life (3). QOL-SP questionnaire, developed by Fernandez et al (5), is specifically designed for critically ill patients. This is one of the few instruments that have been validated in a critical care population, but it is neither widely used nor well known in the critical care community. A few studies have used QOL-SP to assess medical (6), surgical (7), or multiple trauma patients (8), and to measure the quality of life before ICU, as well as the changes in quality of life from baseline to 6 and 24 months.Despite its limitations, we used this instrument to assess the changes in health-related quality of life in people who survived critical illness in a Greek medical-surgical ICU at 6, 12, and 18 months after ICU discharge, and to compare these data with their pre-admission status.  相似文献   
27.
28.
Purpose

Scientific data regarding intravenous iron supplementation in peritoneal dialysis (PD) patients are scarce. In attempting to administer the minimum monthly IV iron dose that could improve erythropoiesis, we wanted to assess the safety and efficacy of monthly maintenance intravenous administration of 100 mg iron sucrose in PD patients.

Methods

In a 9-month prospective study, all clinically stable PD patients received intravenously 200 mg of iron sucrose as a loading dose, followed by monthly doses of 100 mg for five consecutive months. Levels of hemoglobin (Hb), ferritin, transferrin saturation (TSAT), reticulocyte hemoglobin content (CHr) and C-reactive protein (CRP) were measured before each administration and 3 months after the last iron infusion. Also, doses of concurrent erythropoietin administration were recorded.

Results

Eighteen patients were eligible for the study. Mean levels of Hb and ferritin increased significantly (from 10.0 to 10.9 mg/dL, p?=?0.01 and from 143 to 260 ng/mL, p?=?0.005), as well as the increase in TSAT levels approached borderline significance (from 26.2 to 33.1%, p?=?0.07). During the 6 months of iron administration, the erythropoietin dose was reduced in five patients and discontinued in one. During the 3 months following the last iron infusion, three of them again raised the erythropoietin dose to previous levels. None of the patients experienced any side effects related to IV iron administration.

Conclusions

A monthly maintenance intravenous dose of 100 mg iron sucrose may be a practical, effective, and safe in the short term, treatment of anemia in PD patients resulting in improved hemoglobin levels, iron indices, and erythropoietin response.

  相似文献   
29.

Background  

Tissue inhibitors of metalloproteinases (TIMPs) play a key role in tissue degradation and remodeling. Since chronic inflammation is associated with tissue remodeling in inflammatory bowel disease (IBD), we evaluated serum TIMP-1 and TIMP-4 levels in IBD patients, in comparison with healthy controls (HC).  相似文献   
30.

Purpose

The Mediterranean diet rich in fruits, vegetables and olive oil has been related to a lower osteoporosis incidence and accordingly to a reduced fracture risk. These observations might be mediated by the active constituents of extra virgin olive oil, and especially polyphenols. In the context of exploring the features of olive oil active constituents on postmenopausal osteoporosis, an extra virgin olive oil total polyphenolic fraction (TPF) was isolated and its effect on the bone loss attenuation was investigated.

Methods

Female Lewis rats were ovariectomized and fed a diet enriched with a total phenolic extract of extra virgin olive oil in a concentration of 800 mg/kg diet.

Results

Oleocanthal, one compound of the polyphenolic fraction, showed a higher relative estrogen receptor binding affinity to the ERα compared to the ERβ. While the TPF only slightly induced the uterine wet weight (490.7 ± 53.7 vs. 432.7 ± 23, p = 0.058), TPF regulated estrogen response genes in the uterus (progesterone receptor, antigen identified by monoclonal antibody Ki67, complement C3). Comparing the quantified bone parameters, the oral TPF substitution did not attenuate the ovariectomy-induced bone loss.

Conclusions

The administration of extra virgin olive oil polyphenols regulated uterine estrogen response marker genes in an E2-agonistic manner. The bone loss induced by estrogen ablation was not mitigated by treatment with the polyphenolic extract.  相似文献   
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