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71.
We evaluated the safety and feasibility of ipsilateral radial and ulnar artery cannulation during the same catheterization procedure. Crossover from radial to femoral was done in 122 patients. Both ipsilateral radial and ulnar catheterization were performed in 16 patients without any complications, which was further supported by Doppler ultrasonography.  相似文献   
72.
Immunoglobulin V regions and the B cell   总被引:7,自引:2,他引:7  
Stewart  AK; Schwartz  RS 《Blood》1994,83(7):1717-1730
  相似文献   
73.
Quito  FL; Beh  J; Bashayan  O; Basilico  C; Basch  RS 《Blood》1996,87(4):1282-1291
Fibroblast growth factor-4 (FGF-4), a highly mitogenic protein encoded by the k-fgf/hst oncogene, stimulates the growth of a variety of cells of mesenchymal and neuroectodermal origin. Addition of FGF-4 to human long-term bone marrow cultures increased both the cell density of the stromal layer and the number of hematopoietic colony forming cells in the cultures in a dose-dependent manner. Hematopoiesis in the stromal layer persisted for up to 8 months. Erythropoiesis was maintained for up to 4 weeks, but granulocytes were the predominant nonadherent cell type. Cultures treated with FGF had increased numbers of monocytes compared with control cultures and some CD14+, CD45+ monocytes could still be detected after 8 months of continuous culture. The addition of the growth factor increased the rate of growth of the stromal layer and appeared to delay its senescence. Subcultures made in the presence of FGF-4 had up to 10-fold increases in plating efficiency and grew as relatively uniform monolayers. These subcultures retained the capacity to support hematopoiesis for several months, while untreated subcultures, made without FGF-4, grew erratically and generally lost the capacity to support hematopoiesis within 4 to 6 weeks. The improved growth after subculture greatly enhanced the reliability of limit- dilution assays of multipotential hematopoietic stem cells that use stromal cell monolayers. The primary effect of FGF-4 appeared to be on the stromal cells of the long-term bone marrow cultures, but a direct effect on hematopoietic progenitors could not be ruled out.  相似文献   
74.

Background

The placement of a central venous catheter for the administration of vasopressors is still recommended and required by many institutions because of concern about complications associated with peripheral administration of vasopressors.

Objective

Our aim was to determine the incidence of complications from the administration of vasopressors through peripheral venous catheters (PVC) in patients with circulatory shock, and to identify the factors associated with these complications.

Methods

This was a prospective, observational study conducted in the emergency department (ED) of a tertiary care medical center. Patients presenting to the ED with circulatory shock and in whom a vasopressor was started through a PVC were included. Research fellows examined the i.v. access site for complications twice daily during the period of peripheral vasopressor administration, then daily up to 48 h after treatment discontinuation or until the patient expired.

Results

Of the 55 patients that were recruited, 3 (5.45% overall, 6% of patients receiving norepinephrine) developed complications; none were major. Two developed local extravasation and one developed local thrombophlebitis. All three complications occurred during the vasopressor infusion, none in the 48 h after discontinuation, and none required any medical or surgical intervention. Two of the three complications occurred in the hand, and all occurred in patients receiving norepinephrine and with 20-gauge catheters.

Conclusions

The incidence of complications from the administration of vasopressors through a PVC is small and did not result in significant morbidity in this study. Larger prospective studies are needed to better determine the factors that are associated with these complications, and identify patients in whom this practice is safe.  相似文献   
75.

Around one third of schizophrenia patients are non-responders to antipsychotic therapy. The present study aimed to delineate the pathway-phenotypes of non-remitters (NRTT) and partial remitters (PRTT) to treatment with antipsychotics as defined using the Global Clinical Impression scales. We recruited 60 NRTT, 50 PRTT and 43 healthy controls and measured schizophrenia symptoms, neurocognitive tests, plasma CCL11, interleukin-(IL)-6, IL-10, Dickkopf protein 1 (DKK1), high mobility group box-1 protein (HMGB1), κ- and μ-opioid receptors (KOR and MOR, respectively), endomorphin-2 (EM-2), and β-endorphin. Soft independent modeling of class analogy (SIMCA) showed that NRTT and PRTT are significantly discriminated with a cross-validated accuracy of 94.7% and are qualitatively distinct classes using symptomatome, and neuro-immune-opioid-cognitome (NIOC) features as modeling variables. Moreover, a NIOC pathway phenotype discriminated PRTT from healthy controls with an accuracy of 100% indicating that PRTT and controls are two qualitative distinct classes. Using NIOC features as discriminatory variables in SIMCA showed that all PRTT were rejected as belonging to the normal control class and authenticated as belonging to their target class. In conclusion, a non-response to treatment can best be profiled using a SIMCA model constructed using symptomatome and NIOC features. A partial response should be delineated using SIMCA by authenticating patients as controls or PRTT instead of using scale-derived cut-off values or a number of scale items being rated mild or better. The results show that PRTT is characterized by an active NIOC pathway phenotype and that both NRTT and PRTT should be treated by targeting neuro-immune and opioid pathways.

  相似文献   
76.
Clark  Hannah  Rana  Rezwanul  Gow  Jeff  Pearson  Melissa  van der Touw  Tom  Smart  Neil 《Heart failure reviews》2022,27(2):559-572
Heart Failure Reviews - Heart failure with preserved ejection fraction (HFpEF) is problematic to treat, with guidelines for HFpEF management concentrated on treating prevalent comorbidities. The...  相似文献   
77.

Aim of the work

To investigate the role of endothelial protein C receptor (EPCR) (membrane and soluble forms) as a biomarker of lupus nephritis (LN) in systemic lupus erythematosus (SLE) patients and to study its relation to the prognosis and response to treatment.

Patients and methods

The study included 30 SLE patients and 30 matched healthy volunteers as well as 10 renal biopsies from surgical nephrectomy as a control for membranous (mEPCR) examination. SLE disease activity index-2000 and damage index were assessed. Serum sEPCR was measured. Renal expression of mEPCR was analyzed. All patients were reassessed after 3?months.

Results

Patients were 26 females and 4 males with a mean age of 29.6?±?10.04?years and disease duration of 4.4?±?3.5?years. Their mean SLEDAI was 13.9?±?9.9 and damage index 1?±?1.5. Serum levels of sEPCR were significantly higher in patients with LN (19.9?±?5.7?ng/ml) than those without (8.95?±?4.2?ng/ml) and controls (5.3?±?2.6?ng/ml)(p?<?0.001). SLE patients with cutaneous vasculitis (n?=?9) had significantly higher sEPCR levels than those without (18.1?±?7.8 vs 10.2?±?5.2?ng/ml)(p?=?0.02). There was a significant correlation between sEPCR percentage of change and of SLEDAI-2k with and without LN (p?<?0.01 and p?<?0.05). A significant difference was observed in sEPCR according to the prognosis and treatment response after 3?months. mEPCR stained positively in glomeruli and tubules of LN patients with no relation to histopathological grading.

Conclusion

sEPCR plays a role in the pathogenesis, is related to a bad prognosis and poor response to treatment in LN. mEPCR was not related to LN grading.  相似文献   
78.
Dynamic magnetic resonance imaging (dynamic MRI) was used to examine the synovial membrane in the knee joints of 15 patients with rheumatoid arthritis (RA) in order to investigate the relationship between pathological and MRI findings. Signal intensities in the regions of interest (ROI), identified as the synovial membrane of the suprapatellar pouch, were measured on MR images. Signal intensities at various times after the injection of contrast medium Gd–diethylenetriaminopentoacetic acid (Gd–DTPA) were normalized relative to the signal intensity at 80s, and designated as the normalized signal intensity (NSI). Pathological findings were quantified, and the types of inflamed synovial membrane were classified as either acute or chronic. A significant difference in NSI was observed between acute and chronic types (P 0.05). Dynamic MRI was capable of classifying acute and chronic RA by measuring NSI 20s after contrast medium injection. Dynamic MRI was therefore shown to be useful for assessing regional synovial inflammation.  相似文献   
79.
Enterococcus faecalis is a highly stress resistant opportunistic pathogen. The intrinsic ruggedness of this bacterium is supposed to be the basis of its capacity to colonize the hostile environments of hospitals and to cause several kinds of infections. We show in this work that general resistance to very different environmental stresses depends on the ability of E. faecalis to maintain redox balance via lactate dehydrogenase (LDH). Furthermore, LDH-deficient mutants are less successful than the wild type at colonizing host organs in a murine model of systemic infection. Taken together, our results, as well as those previously published for Staphylococcus aureus (A. R. Richardson, S. J. Libby, and F. C. Fang, Science 319:1672–1676, 2008), identify LDH as an attractive drug target. These drugs may have additional applications, as in the fight against glycopeptide antibiotic-resistant bacteria and even cancer.  相似文献   
80.
Bacterial-derived lipopolysaccharides (LPS) play an essential role in the inflammatory process of inflammatory bowel disease. A defective intestinal tight junction (TJ) barrier is an important pathogenic factor of inflammatory bowel disease and other inflammatory conditions of the gut. Despite its importance in mediating intestinal inflammation, the physiological effects of LPS on the intestinal epithelial barrier remain unclear. The major aims of this study were to determine the effects of physiologically relevant concentrations of LPS (0 to 1 ng/mL) on intestinal barrier function using an in vitro (filter-grown Caco-2 monolayers) and an in vivo (mouse intestinal perfusion) intestinal epithelial model system. LPS, at physiologically relevant concentrations (0 to 1 ng/mL), in the basolateral compartment produced a time-dependent increase in Caco-2 TJ permeability without inducing cell death. Intraperitoneal injection of LPS (0.1 mg/kg), leading to clinically relevant plasma concentrations, also caused a time-dependent increase in intestinal permeability in vivo. The LPS-induced increase in intestinal TJ permeability was mediated by an increase in enterocyte membrane TLR-4 expression and a TLR-4–dependent increase in membrane colocalization of membrane-associated protein CD14. In conclusion, these studies show for the first time that LPS causes an increase in intestinal permeability via an intracellular mechanism involving TLR-4–dependent up-regulation of CD14 membrane expression.An integral function of intestinal epithelial cells is to act as a physical barrier, separating the noxious luminal environment from the underlying lamina propria and the deeper intestinal layers.1,2 The apically located tight junctions (TJs) form a paracellular seal between the lateral membranes of adjacent intestinal epithelial cells, and act as a structural and functional barrier against paracellular flux of luminal substances. Defective intestinal epithelial TJ barrier has been shown to be an important pathogenic factor of inflammatory bowel disease (IBD) and necrotizing enterocolitis (NEC) by allowing paracellular permeation of luminal antigens that elicit and promote inflammatory response.1,2 Both clinical and animal studies have shown the importance of a defective intestinal TJ barrier in the development and prolongation of intestinal inflammation in IBD and NEC.1–5 These studies have shown that normalization of intestinal barrier in patients with active Crohn’s disease predicts prolonged clinical remission, whereas a persistent increase in intestinal permeability portends poor clinical outcome with rapid recurrence of the disease.6,7 Additionally, animal studies have also shown that a primary defect in intestinal junctional complexes was sufficient to induce or aggravate intestinal inflammation in murine models of IBD,8,9 whereas therapeutic tightening or enhancement of the intestinal TJ barrier prevented the development of intestinal inflammation.3,10The terms endotoxin and lipopolysaccharide (LPS) are used interchangeably and refer to the major cell wall component of Gram-negative bacteria.11,12 LPS are complex amphiphilic molecules having a hydrophobic (consisting of lipid A) and a hydrophilic (consisting of carbohydrate core and polysaccharide O-antigen) component and are released from bacterial cell wall by shedding or through bacterial lysis.11–13 LPS concentrations are highest in the gut lumen, where many trillions of commensal bacteria reside. Normally, LPS in the gut lumen do not penetrate across the healthy intestinal epithelium14,15; however, in intestinal permeability disorders, the defective TJ barrier allows paracellular flux of LPS and other luminal antigens.11–13,16–19 The intestinal tissue and circulating LPS levels are markedly elevated in IBD and NEC, and play an important role in mediating inflammatory response.11–13,16–18 The involvement of LPS in the initiation and propagation of intestinal inflammation in IBD and NEC has been well demonstrated.20–23 These studies have shown LPS to be an important contributing factor of intestinal inflammation, and removal of circulating LPS accelerated the clinical improvement of IBD and NEC.20,22,23 Despite the importance of a defective intestinal barrier in the accentuation and prolongation of intestinal inflammation in IBD and NEC,3,6,9,20,22 the effects of circulating levels of LPS on the intestinal epithelial barrier remain unknown. Because LPS levels are markedly elevated in these diseases and play an important role in the inflammatory process, understanding the effects of LPS on intestinal barrier function has important potential clinical significance.In normal healthy individuals, plasma concentrations of LPS range from undetectable levels up to 0.2 ng/mL.11,12,20,22 A variety of physiological factors such as prolonged physical exertion, high-fat diet, physiological stresses, or heat can lead to elevated plasma LPS levels as high as 1 to 2 ng/mL.24–27 Patients with intestinal permeability disorders such as Crohn’s disease, NEC, acute pancreatitis, alcoholic liver disease, and critical illnesses also have elevated plasma LPS levels ranging up to 2 to 10 ng/mL.11–13,20,22,28 Based on these reports, we consider LPS levels of 0 to 1.0 ng/mL to be physiologically relevant and 0 to 10 ng/mL to be clinically relevant. (For reference, the concentration of LPS in the gut lumen has been reported to be 1.8 μg/mL in the rat distal ileum.29,30) Inexplicably, in most of the published studies, extreme pharmacological concentrations of LPS ranging between 50 and 1000 μg/mL, which exceed the physiologically achievable concentrations by 104- to 107-fold, have been used to assess various biological responses.30–34 At these extreme concentrations, LPS causes rapid cell death in various cell types studied, including in intestinal and immune cells,30,33–35 and does not provide accurate depiction of biological activity of LPS. Herein, we show that LPS, at physiologically and clinically relevant concentrations (0 to 10 ng/mL), does not cause intestinal epithelial cell death, but causes a selective increase in intestinal TJ permeability in vitro and in vivo. These studies also show for the first time that pattern recognition receptors Toll-like receptor 4 (TLR-4) and CD14 play a central role in the modulation of the intestinal epithelial TJ barrier.  相似文献   
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