Effects of sodium loading and depletion in normotensive first-degree relatives of essential hypertensives.

To examine potential mechanisms responsible for the greater prevalence of hypertension among relatives of hypertensives than among relatives of normotensives, we subjected 43 normotensive first-degree relatives of known essential hypertensives and 43 age-, race-, and sex-matched normal subjects with no family history of hypertension to sodium loading and depletion. The data show that the relatives had higher blood pressures than did controls. They also had higher PRA values before and after a 2 L intravenous saline infusion over 4 hr. In addition, the relatives excreted less (p less than 0.05) sodium on the day of the infusion than did the controls. PA values and UNe excretion in the two groups did not differ. In the relatives, age correlated with systolic and diastolic blood pressure. Age correlated inversely with the 24 h urine sodium excretion on the sodium loading day. These correlations were not observed in controls. Normotensive first-degree relatives of hypertensives differ from relatives of nonhypertensives in that they have higher PRA values and a blunted natriuretic response to a saline load. These features may predispose them to the development of hypertension.     

Large-volume leukapheresis for collection of mononuclear cells for hematopoietic rescue in Hodgkin's disease

BACKGROUND: Peripheral blood mononuclear cells (MNCs) collected by leukapheresis contain hematopoietic stem and progenitor cells that provide autologous hematopoietic rescue after high-dose chemotherapy, an approach that offers a significant benefit to patients with recurrent Hodgkin's disease. However, patients with low MNC counts may require 10 or more standard leukapheresis procedures for the collection of sufficient cells for hematopoietic rescue. STUDY DESIGN AND METHODS: The effectiveness of steady-state large-volume leukapheresis (LVL; 15- 35 L blood processed) was evaluated as a method for collecting MNCs for hematopoietic rescue in seven patients with recurrent Hodgkin's disease. LVL was performed on 2 consecutive days per week to collect 7 × 10(8) MNCs per kg. The circulating MNC counts on the first day of LVL and the total numbers of LVL, of MNCs collected, and of liters of blood processed were determined per patient. After high-dose chemotherapy and MNC transfusion, days to granulocyte and platelet engraftment were recorded. RESULTS: On the first day of LVL, patients had median circulating MNCs of 1536 (range, 504–3950) × 10(6) per L. The median number of LVL procedures per patient was four (range, 1.25-6), and the median L per kg of blood processed was 1.57 (range, 0.38-4.03). Simple regression analysis plotting L per kg against initial MNCs gave a curve with the equation y = e(1.42-(6.31 × 10E-4)x) (correlation coefficient = -0.97, R2 = 0.95, exponential fit). Without posttransfusion growth- factor support, median days to granulocyte engraftment were 19 (range, 12–26) and those to platelet transfusion independence were 34.5 (range, 10–57). CONCLUSION: LVL provides a useful method of collecting MNCs for hematopoietic rescue in patients with Hodgkin's disease. The patient's baseline MNC count provides a useful estimate of the volume required for LVL.     

The effect of platelets and red cells on granulocytes stored at 22 degrees C

Granulocyte concentrates contain varying numbers of platelets and red cells depending upon the method of collection. Either platelet or red cell concentrations may be as high as 2.0 × 10(12) per I. Studies were done on unwashed and washed granulocyte concentrates and on pure granulocyte suspensions with known numbers of platelets or red cells added. These suspensions or concentrates were stored for 72 hours at 22 degrees C. In both experiments, the following were measured: leukocyte and absolute granulocyte counts, dye exclusion, chemotaxis, plasma glucose, plasma pH, and osmolality. Red cell contamination did not adversely effect granulocyte storage. Platelets, however, did contribute to the functional deterioration of stored granulocytes. In the presence of high concentrations of platelets, both granulocyte dye exclusion and chemotaxis were adversely affected at 48 hours of storage. In another experiment, fresh autologous granulocytes incubated for 18 hours in hydroxyethyl starch-citrated-plasma obtained from stored granulocyte concentrates showed a progressive decrease in chemotaxis related to the age of the stored plasma. Glucose supplementation of the spent plasma maintained chemotactic activity. Contamination of granulocyte concentrates with other cells and the availability of glucose to granulocytes are variables affecting the short-term liquid storage of granulocytes at 22 degrees C.     

Perioperative Outcomes and Complications in Patients With Heart Failure Following Total Knee Arthroplasty

Background

Heart failure (HF) is a common comorbidity in the aging population and they will require major elective surgery. The purpose of this study is to determine if HF is a risk factor for adverse perioperative outcomes and short-term complications following total knee arthroplasty.

High Efficiency Particulate Air Filters Do Not Affect Acute Infection Rates During Primary Total Joint Arthroplasty Using Forced Air Warmers

Background

Studies have suggested that forced-air warmers (FAWs) increase contamination of the surgical site. In response, FAWs with high efficiency particulate air filters (FAW-HEPA) were introduced. This study compared infection rates following primary total joint arthroplasty (TJA) using FAW and FAW-HEPA.

Association of atherogenic low-density lipoprotein subfractions with carotid atherosclerosis

Patients with carotid atherosclerosis are at increased risk of both stroke and ischaemic heart disease. Low-density lipoprotein (LDL) is a heterogeneous group of particles, with small, dense particles being more atherogenic. We studied 79 patients (51 men, mean +/- SD age 62.4 +/- 11.7 years) referred for Doppler ultrasound assessment of the carotid arteries. Evidence of carotid atherosclerosis, defined as the presence of atherosclerotic plaque, stenosis or occlusion in one or more of the six carotid artery segments examined, was found in 44 patients (56%). LDL subfractions were analysed by disc polyacrylamide gel electrophoresis with prior ultracentrifugation of serum to remove chylomicrons. This method produces a LDL score; the higher the score, the greater the proportion of the more atherogenic LDL subfractions. Mean LDL score was significantly higher in diseased patients (mean +/- SD, 1.56 +/- 0.61) than the normal group (1.26 +/- 0.65) (t = 2.12, p = 0.037). There was no significant association between LDL score and severity of carotid artery stenosis. Age (adjusted odds ratio 1.09, 95% CI 1.03-1.15) and smoking history (2.09, 95% CI 1.10-3.98) predicted carotid atherosclerosis in logistic regression analysis, with LDL score achieving borderline significance (2.20, 95% CI 0.91-5.29). Small, dense LDL subfractions are associated with carotid atherosclerosis and may be a modifiable risk factor for stroke as well as ischaemic heart disease.      

Comparison of five cardiac markers in the detection of reperfusion after thrombolysis in acute myocardial infarction.

OBJECTIVE--To investigate and compare the clinical usefulness of serial measurements of five cardiac marker proteins, namely creatine kinase (CK), CK-MB mass, myoglobin, troponin T, and myosin light chain 1, in the early detection of reperfusion after thrombolytic treatment. METHOD--Serial blood samples were taken from 26 patients presenting with acute myocardial infarction. Concentrations of the five markers were assayed in each sample. Thrombolytic treatment was given to the patients who were divided into those who reperfused (n = 17, group A) and those who failed to reperfuse (n = 9, group B) on the basis of clinical signs and angiography within 24 h. RESULTS--The release profiles of CK, CK-MB mass, myoglobin, and troponin T for patients in group A differed from those of patients in group B. No difference was observed in the release profile of myosin light chain 1 between the two groups. The time to peak concentration of CK, CK-MB mass, myoglobin, and troponin T occurred significantly earlier in patients of group A than in those of group B, with myoglobin peaking earlier than the other markers. An index, defined as the ratio of the concentration of each marker immediately before and 2 h after the start of thrombolytic treatment, was calculated for each marker in groups A and B. The 2 h myoglobin and troponin T indices were significantly different between groups A and B. The diagnostic efficiency of the myoglobin index, however, was best at 85%. CONCLUSIONS--These studies suggest that myoglobin has greater potential than the other markers examined in the detection of reperfusion after thrombolytic treatment.     

Isolation and characterization of the mouse metallothionein-I gene.

Double-stranded cDNA was synthesized from a mouse liver mRNA fraction enriched for metallothionein mRNA activity, ligated to restriction site linkers, inserted into pBR322, and used to transform Escherichia coli chi 1776. The sequence of the largest plasmid containing DNA that hybridized to metallothionein mRNA was determined and shown to contain a 380-base-pair insert that includes the entire coding region and 3' untranslated region of metallothionein-I. The metallothionein-I insert was nick-translated and used to screen both a mouse myeloma and a mouse embryo DNA library in bacteriophage lambda. A metallothionein-I genomic clone containing 13-15 kilobase pairs of mouse DNA was isolated from each library. Both contain a 3.8-kilobase-pair EcoRI fragment that hybridizes to the metallothionein-I probe. The location, size, and orientation of the metallothionein-I gene within the 3.8-kilobase-pair fragment were determined by heteroduplex and restriction mapping. The gene spans 1.1 kilobase pairs and contains at least two introns.     

Lactoferrin: a promoter of polymorphonuclear leukocyte adhesiveness

Polymorphonuclear leukocytes (PMN) degranulate, adhere to vascular endothelium, or aggregate to each other following exposure of the cells to high concentrations of chemotactic stimuli such as formyl-methionyl- leucyl phenylalanine (FMLP). PMN released the specific granule product lactoferrin more readily in response to chemotactic stimuli, which correlated with promotion of PMN aggregation as measured by light transmission and enhanced PMN adherence. Both concanavalin A (Con-A) and phorbol myristate acetate (PMA), agents that lead to specific granule discharge, induced and sustained human PMN aggregation. Similarly, supernatants, generated from Con-A-treated PMN, aggregated fresh PMN in the presence of alpha-methylmannoside, a competitive inhibitor of the lectin. Anti-human lactoferrin IgG but not normal goat IgG blunted the aggregation elicited by both PMA and FMLP. Both human milk lactoferrin and rabbit PMN lactoferrin aggregated human lactoferrin promoted PMN adherence to endothelial cells. The enhanced PMN stickiness was correlated with the early phase of degranulation. Thus, PMN lactoferrin serves an autoregulatory role to retain PMN at inflammatory sites to amplify the inflammatory response.