The capacity of mitogen-responsive T cells to “home” to their tissue of origin, analyzed by means of chromosome markers

Lance and Taub (1) showed that when radioactively labeled lymphocytes were injected into a syngeneic mouse and the lymph node cells of this animal transferred to a second syngeneic recipient, the proportion of radioactivity found in the lymph node relative to the amount present in the spleen of the secondary recipient had increased markedly. The interpretation of this result was that some lymphocytes have the capacity to “home” to their organ of origin. The purpose of the experiments described here was to test the “homing” copacity of T cells by a method that did not involve radioactive labeling. It has been shown elsewhere that some or all mouse T cells are stimulated to divide in culture by the mitogens phytohemagglutinin (PHA) and concanavalin A (Con A) (2). We therefore elected to inject karyotypically distinct lymphocytes into syngeneic recipients and to follow their subsequent distribution by culture of lymph node and spleen cells of the recipient with PHA or Con A. In this manner the homing capacities of spleen and lymph node T cells could be determined, and furthermore, the effects of labeling with chromium-51 ((51)Cr) could be assayed with respect to the persistence of mitogen responsiveness in the injected cells.     

Feasibility and success of a single-donor red cell program for pediatric elective surgery patients

Although the risks of allogeneic blood transfusions are small, it is wise to limit donor exposure whenever possible. A program has been developed in which one donor provided all red cell (RBC) units for each patient awaiting elective surgery. Patients were mostly children who were ineligible for autologous blood donation. Seventy-three patients and 115 donors (mostly parents) entered the program. Of the 115 donors, 90 (78%) were eligible to participate and 25 (22%) were ineligible; 21 were ineligible because of RBC incompatibility. For each of the 73 patients, one eligible donor was selected to donate all RBC units. Preoperative RBC orders were 1 to 2 units for 41 patients and > or = 3 units for 32 patients. Of the 73 donors, 58 (79%) gave all RBC units ordered; 15 (21%) failed to complete all donations, but only 1 because of anemia (hematocrit < 33% [0.33]). Of 73 patients entered, 46 (63%) underwent transfusion, and 27 (37%) did not. Of 46 patients transfused, 38 (83%) received only single-donor RBCs. Thus, the RBC needs of nearly all pediatric elective surgery patients were provided by a single donor for each patient. Single-donor blood programs should be considered for elective surgery patients who are ineligible for autologous blood donation and who would otherwise be exposed to multiple donors.     

Comparison of plateletpheresis with a standard and an improved collection device

A blood cell separator with a specialized separation chamber ([TNX-6]CS- 3000 Plus) was developed for the collection of platelet concentrates with higher platelet yields and lower white cell contamination than obtained with the standard blood cell separator (CS-3000). To compare these devices, normal donors were scheduled for paired plateletpheresis procedures spaced 4 weeks apart, with one procedure using the CS-3000 Plus and the other using the CS-3000. Overall, the platelet yield per unit (mean +/− SEM) was 4.3 +/− 0.1 × 10(11) with the CS-3000 Plus versus 3.7 +/− 0.1 × 10(11) with the CS-3000 (p < 0.001), and the white cell contamination per unit (mean +/− SEM) with the former was 2.4 +/− 0.7 × 10(6) versus 84.1 +/− 21.1 × 10(6) with the latter (p < 0.001). The sequence of procedures (i.e., the order in which the devices were paired) was selected randomly, and similar results were found regardless of sequence. When donors with predonation platelet counts of > or = 200 × 10(9) per L (n = 21) were studied separately, 76 percent of the collections by the CS-3000 Plus contained > or = 4 × 10(11) platelets versus 34 percent of those by the CS-3000 (p < 0.01), and 93 percent of the collections by the former contained < 5 × 10(6) white cells (69% contained < 1 × 10(6)) versus 0 percent of those by the latter (p < 0.01). Thus, platelet collections with the TNX-6 chamber consistently demonstrated high platelet yields and strikingly low white cell contamination–qualities that justify converting standard devices to devices with a TNX-6 chamber.     

Adverse change in low-density lipoprotein subfractions profile with oestrogen-only hormone replacement therapy

In a prospective longitudinal study in 17 women, we investigated the effects of surgical menopause and subsequent oestrogen-only hormone replacement therapy (HRT) on plasma concentrations of total cholesterol, HDL cholesterol, LDL cholesterol, triglyceride and LDL subfractions profile. Plasma LDL is a heterogeneous population of particles of varying size, density and chemical composition. The predominance of small LDL particles is a newly-recognized risk factor for coronary artery disease. The LDL score is used to describe LDL subfractions profile and the greater the score, the higher the proportion of small LDL particles. Six weeks after hysterectomy and bilateral oopherectomy, total cholesterol and triglyceride concentrations were significantly increased (p < 0.01) as well as the LDL score (p < 0.05). After 6 weeks of oestrogen-only HRT, total cholesterol concentration was significantly lower and HDL cholesterol concentration significantly higher than before the treatment (p < 0.05). At the same time, mean LDL score significantly increased and in none of the women did LDL subfractions profile change favourably.      

An exploratory study with an adaptive continuous intravenous furosemide regimen in neonates treated with extracorporeal membrane oxygenation

Introduction  

The objective of the present study was to explore a continuous intravenous furosemide regimen that adapts to urine output in neonates treated with extracorporeal membrane oxygenation (ECMO).     

A statistical model for estimating donor postdonation platelet counts after plateletpheresis

BACKGROUND: To avoid the need, in serial apheresis donors, either to delay plateletpheresis until a predonation platelet count is completed or to obtain a postdonation count after each procedure, a statistical model has been developed to predict the postdonation platelet count from the donor predonation platelet count, weight, and hematocrit. STUDY DESIGN AND METHODS: Predonation and postdonation platelet counts were measured in two groups of approximately 100 consecutive donors (Group A to test the model and Group B to validate it), and the postdonation counts were calculated with the model. Using stepwise multiple linear regression from donor data, estimated postdonation platelet counts were found to be comparable to the postdonation platelet counts actually measured. RESULTS: Estimated postdonation platelet counts × 10(9) per L (mean +/− SD) for each group, respectively, were Group A, 195 +/− 35, versus actual platelet counts of 195 +/− 39 (p = 0.43), and Group B, 183 +/− 36, versus actual platelet counts of 189 +/− 34 (p = 0.14). Sensitivity and specificity, respectively, were Group A, 57 and 99 percent and Group B, 62 and 99 percent. CONCLUSION: For most serial apheresis donors, application of this predictor model should preclude the need to obtain an extra postdonation platelet count.     

Nurse middle managers contributions to patient‐centred care: A ‘managerial work’ analysis

Nurse middle managers are in an ideal position to facilitate patient‐centred care. However, their contribution is underexposed in literature due to difficulties to articulate this in practice. This paper explores how nurse middle managers contribute to patient‐centred care in hospitals. A combination of time‐use analysis and ethnographic work was used to disclose their contribution to patient‐centred care at a micro level. Sixteen nurse managers were shadowed for over 560 hours in four hospitals. Some nurse middle managers seldom contribute to patient‐centred care. Others are involved in direct patient care, but this does not result in patient‐centred practices. At one hospital, the nurse middle managers did contribute to patient‐centred care. Here balancing between “organizing work” and “caring work” is seen as a precondition for their patient‐centeredness. Other important themes are feedback mechanisms; place matters; with whom to talk and how to frame the issues at stake; and behavioral style. Both “hands‐on” and “heads‐on” caring work of nurse middle managers enhances their patient‐centeredness. This study is the first of its kind to obtain insight in the often difficult to articulate “doings” of nurse middle managers with regard to patient‐centred care through combining time‐use analysis with ethnographic work.     

Failure in the application of fragility fracture prevention guidelines

Introduction

The cost of fragility fractures to the UK economy is predicted to reach £2.2 billion by 2025. We studied our hip fracture population to establish whether national guidelines on fragility fracture prevention were being followed, and whether high risk patients were identified and treated by local care services.

Methods

Data on a consecutive series of trauma hip fracture admissions were collected prospectively over 14 months. National Institute for Health and Care Excellence (NICE) and National Osteoporosis Guideline Group (NOGG) recommendations and FRAX^® risk calculations were applied to patients prior to their admission with a new hip fracture.

Results

Overall, 94 patients were assessed against national guidelines. The mean population age was 77 years. Almost a quarter (22%) of patients had suffered a previous fragility fracture. The mean FRAX^® ten-year probability of hip fracture was 7%. According to guidelines, 45% of the study population required treatment, 35% fulfilled criteria for investigation and reassessment, and 20% needed no further management. In practice, 27% received treatment, 4% had undergone dual energy x-ray absorptiometry and were untreated, and 69% had not been investigated and were untreated. In patients meeting intervention thresholds, only 33% of those who required treatment were receiving treatment in practice.

Conclusions

In conjunction with NICE and NOGG recommendations, FRAX^® was able to identify 80% of our fracture population as intermediate or high risk on the day of fracture. Correct management was evident in a third of cases with a pattern of inferior guideline compliance seen in a London population. There remains a lack of clarity over the duty of care in fragility fracture prevention.     

Urban legends series: oral candidosis

Candida species (spp) are commensal yeast that can only instigate oral infection (oral candidosis – OC) when there is an underlying predisposing condition in the host. We investigated four controversial topics on OC: (i) How can a microbiological determination of OC be made as Candida spp. are commensal yeasts and not all of them form hyphae or pseudohyphae during infection? (ii) Is median rhomboid glossitis (MRG) a manifestation of candidal infection? (iii) Can candidal infection cause palate papillary hyperplasia (PPH)? (iv) What is the best therapeutic treatment for denture‐associated erythematous stomatitis (DAES)? Results from extensive literature searches, including a systematic review, suggested the following: (i) the diagnosis of OC merely on the basis of the presence of yeasts is an oversimplification of a complex process. No convincing evidence of a single test or method better able to discriminate the transition from candidal saprophytism to pathogenicity has been reported in the literature; (ii–iii) conclusive evidence of a direct aetiopathogenic relationship between MRG and PPH and candidal infection has not been found; and (iv) only limited evidence is available for any DAES treatment, thus making it impossible to make strong therapeutic recommendations.