Human mesenchymal stem cells improve myocardial performance in a splenectomized rat model of chronic myocardial infarction.

BACKGROUND/PURPOSE: Cellular therapy has been applied to animal studies and clinical trials for acute or subacute myocardial infarction. Little is known about the effect of cell therapy on chronic myocardial infarction. The goal of this study was to investigate myocardial performance after human bone marrow-derived mesenchymal stem cell (hMSCs) transplantation in rats with chronic myocardial infarction. METHODS: The hMSCs were obtained from adult human bone marrow and expanded in vitro. The purity and characteristics of hMSCs were identified by flow cytometry and immunophenotyping. Splenectomy in male rats was performed to prevent immune reaction. One week after splenectomy, ligation of the left anterior descending coronary artery was performed to induce myocardial infarction. Four weeks after ligation of the coronary artery, culture-expanded hMSCs were injected intramyocardially at the left anterior free wall. Left ventricular function measured by echocardiography, infarct size and immunohistochemical stain were performed to evaluate the effect of the therapy. RESULTS: The engrafted hMSCs were positive for the cardiac marker troponin T. Infarct size (35.4 +/- 3.4% vs. 53.3 +/- 3.0%, p < 0.001) and fibrotic area (2.6 +/- 0.1% vs. 5.9 +/- 0.2%, p < 0.001) were significantly smaller in the hMSC-treated group than in the control group at 28 days after therapy. hMSC transplantation resulted in smaller left ventricular end-diastolic dimension (6.5 +/- 0.1 mm vs. 7.9 +/- 0.7 mm, p < 0.001) and better left ventricular ejection fraction (88.7 +/- 1.2% vs. 65.8 +/- 2.5%, p < 0.001) than in the control group. Capillary density was markedly increased after hMSC transplantation compared with the control group. CONCLUSION: This study demonstrates that intramyocardial transplantation of hMSCs improves cardiac function after chronic myocardial infarction through enhancement of angiogenesis and myogenesis in the ischemic myocardium. Transplantation of hMSCs for myocardial regeneration may become the future therapy for chronic myocardial infarction.     

Sympathetic and noradrenaline effects on C-fibre transmission: single-unit analysis

Single afferent unmyelinated fibres were dissected from the otherwise intact sural nerve in anesthetized rabbits. The sympathetic trunk could be stimulated via electrodes implanted through the abdomen. The response in single C fibres was elicited by electrical stimulation in the cutaneous innervation area of the fibre. Sympathetic stimulation (8 Hz, 1 ms pulses, 5 mA for 60 s) increased the latency in all tested C fibres (2.0% +/- 0.8%, mean +/- SD, n = 17). In 48% of the units the amplitude of the action potential decreased (26.4% +/- 12.3%) during sympathetic stimulation. Infusion of noradrenaline (5 micrograms min-1) increased (7.7% +/- 4.1%) the latency in all units and increased (36.9% +/- 29.8%) the amplitude of 25% of the units. The effects of sympathetic stimulation and noradrenaline infusion were blocked by pre-treatment with phentolamine (3 mg kg-1 i.v.). The results suggest that catecholamines change the membrane properties of unmyelinated fibres.     

Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT

Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis.     

Older people with hip fracture: depression in the postoperative first year

Title. Older people with hip fracture: depression in the postoperative first year. Aim. This paper is a report of a study conducted to describe changes in risk of depressive symptoms and their predictors for older people with hip fracture during the first year following hospital discharge. Background. The prevalence of depression in older people with hip fracture has been reported as 9–47%. However, the longitudinal changes in prevalence rate following hip fracture have not been well‐studied, particularly in Asian countries. Methods. The study was conducted in Taiwan in 2001–2003. A sample of 147 older people with hip fracture was assessed for depressive symptoms before discharge, and at 1, 3, 6 and 12 months after discharge using the Chinese version of the Geriatric Depression Scale. Longitudinal data were analysed by the generalized estimating equation approach. Findings. The majority of participants were at risk for depressive symptoms before discharge (n = 147, 57·8%) and 35·6% (n = 118) 12 months after discharge. These numbers decreased statistically significantly from before discharge to the 1st month after discharge (57·8% vs. 42·6%, P = 0·008), and from the 1st to the 6th month (42·6% vs. 31·3%, P = 0·03), and then remained stable until the 12th month after discharge. Lower emotional‐social support predicted persistent depressive symptoms after discharge (P < 0·01). Conclusion. Timely psychological interventions are suggested within the first 6 months after discharge, especially the first 3 months. Healthcare professionals need to pay attention to older patients with hip fracture who are female, with poorer prefracture functioning and particularly those with lower emotional‐social support.     

Peroxisome proliferator-activated receptor delta agonists attenuated the C-reactive protein-induced pro-inflammation in cardiomyocytes and H9c2 cardiomyoblasts

C-reactive protein (CRP) has emerged as a new marker for cardiovascular diseases. Activation of peroxisome proliferator-activated receptor δ (PPARδ) plays beneficial roles in cardiac disorders. However, the relationship between CRP and PPARδ in cardiac cells remains unclear. This study focused on the underlying molecular mechanisms of CRP and PPARδagonists. Cardiomyocytes and cardiomyoblast cell line (H9c2) were used in different groups: Untreated; 15 μg/ml CRP with or without 1 μM PPARδ agonists (L-165041). CRP increased PPARδ and interleukin-6 expression in cardiomyocytes and H9c2 cardiomyoblasts. NF-κB inducing kinase (NIK) and NF-κB pathway also activated by CRP stimulation. These changes could be inhibited by L-165041 through p38MAPK and c-JNK pathways. However, transfection with siRNA of CD32 CRP receptor did not decrease CRP signaling or reverse the effects of L-165041 in CRP-treated cardiomyocytes and H9c2. Pretreatment with L-165041 attenuated apoptosis induced by hypoxia with or without CRP in H9c2 cardiomyoblasts. CRP up-regulated PPARδ expression in cardiomyocytes and H9c2. L-165041 attenuated CRP-induced pro-inflammatory signaling through p38MAPK and c-JNK in H9c2 cardiomyoblasts. However, PPARδ activation attenuated CRP-induced NF-κB pathway may be independent of CD32. These results may provide new evidence of PPARδ beneficial effects for inflammatory cardiomyopathy.     

Indium-111 labeled platelet deposition following transfemoral angiography

The incidence of thromboembolitic events in patients undergoing transfemoral angiography was examined using indium-111 labeled platelets. Twenty-seven patients received approximately 300 muCi of autologous labeled platelets at least 3 hours before angiography and were scanned with a gamma camera immediately before and after angiography. All patients were free of clinically obvious complications in the 1-2 day period after angiography. Our results showed evidence of platelet deposition at 21 sites other than the puncture site in 12 (44%) patients. Most platelet deposition (54%) occurred along the region between the puncture site and the aortic bifurcation; 24% occurred at sites not traversed by the catheter. At the puncture site itself, there was substantial platelet uptake in 44% of patients. This study indicates the need for further work in determining the most suitable catheter material and in assessing the efficacy of other measures such as anticoagulant or antiplatelet therapy.     

Pharmacokinetics of didanosine in patients with acquired immunodeficiency syndrome or acquired immunodeficiency syndrome-related complex

The pharmacokinetics of didanosine (2',3'-dideoxyinosine) after intravenous and oral administration were evaluated in an open, escalating-dose phase I study in patients with acquired immunodeficiency syndrome (AIDS) or severe AIDS-related complex. Didanosine was administered twice a day for 2 weeks as an intravenous infusion of 60 minutes duration at doses ranging from 0.4 to 16.5 mg/kg, followed by 4 weeks of oral treatment at twice the intravenous dose. Serial blood and urine samples were obtained on the first and final day of intravenous administration and after the first oral dose, as well as at steady state. Didanosine demonstrated linear pharmacokinetic behavior over the dose ranges of 0.4 to 16.5 mg/kg intravenously and 0.8 to 10.2 mg/kg orally. There was no indication of significant changes in pharmacokinetic parameters with repeated administration. The apparent elimination half-life after oral administration was approximately 1.4 hour. Renal clearance values exceeded the glomerular filtration rate, indicating that active tubular secretion of didanosine occurs. Bioavailability of didanosine when administered as a solution with an antacid was approximately 43% for doses from 0.8 to 10.2 mg/kg in patients with AIDS and advanced AIDS-related complex. Bioavailability of didanosine from the citrate-phosphate-buffered solution, the formulation currently used in phase II and expanded access studies, was comparable to the formulation used in the phase I trials.     

A minimal stress model for the assessment of electroacupuncture analgesia in rats under halothane.

The use of anesthetics in acupuncture analgesia is controversial. We evaluate a steady-state light anesthesia model to test whether minimal stress manipulation and reliable measurement of analgesia could be simultaneously achieved during electroacupuncture (EA) in animals. A series of experiments were performed. Firstly, EA compliance and tail-flick latencies (TFL) were compared in rats under 0.1%, 0.3%, 0.5%, 0.7%, or 1.1% halothane for 120min. Under 0.5% halothane, TFL were then measured in groups receiving EA at intensity of 3, 10 or 20 volt (V), 1 or 2mg/kg morphine, 20V EA plus naloxone, or control. Subsequently, the effect of EA on formalin-induced hyperalgesia was tested and c-fos expression in the spinal dorsal horn was analyzed. Rats exhibited profound irritable behaviors and highly variable TFL under 0.1% or 0.3% halothane, as well as a time-dependent increase of TFL under 0.7% or 1.1% halothane. TFL remained constant at 0.5% halothane, and needle insertion and electrical stimulation were well tolerated. Under 0.5% halothane, EA increased TFL and suppressed formalin-induced hyperalgesia in an intensity-dependent and naloxone-reversible manner. EA of 20V prolonged TFL by 74%, suppressed formalin-induced hyperalgesia by 32.6% and decreased c-fos expression by 29.7% at the superficial and deep dorsal horn with statistically significant difference. In conclusion, 0.5% halothane provides a steady-state anesthetic level which enables the humane application of EA stimulus with the least interference on analgesic assessment. This condition serves as a minimal stress EA model in animals devoid of stress-induced analgesia while maintaining physiological and biochemical response in the experiment.     

Long-term use of antecubital veins for plasma exchange. The Canadian Cooperative Multiple Sclerosis Study Group

True or sham plasma exchange was done weekly for 20 weeks in patients in two of the randomization groups in a prospective, blind clinical trial of experimental treatments for multiple sclerosis. Because patients could be randomized to receive sham plasma exchange and placebo medications, it was decided when the trial was designed that the use of fistulae, arteriovenous shunts, venous cutdowns, or other aggressive forms of venous access would not be permitted for any patient. Accordingly, patients judged to have inadequate superficial antecubital veins were ineligible for the trial. To date, only 13 (4.4%) of 294 patients considered for entry into the trial have been rejected on these grounds. In only 4 of the 93 patients undergoing exchange was it necessary to discontinue plasma exchange because of inadequate venous access. In 79.3 percent of the 1207 exchanges done in these patients, there were no problems of any kind with venous access. In 5.4 percent of these 1207 exchanges, it was necessary to terminate the procedure prematurely because of difficulties with patients' veins. Thus, the great majority of patients free of serious systemic illness (other than chronic progressive multiple sclerosis) can undergo weekly plasma exchange for up to 20 weeks using superficial antecubital veins without the need to resort to more invasive methods of venous access.