In vitro and in vivo evaluation of cotton wool filtration of platelet concentrates obtained by automated and manual apheresis

The effect of cotton wool filtration of apheresis platelet concentrates (PCs) on platelet viability and complement activation was evaluated by two laboratories. PCs were prepared by automated (Lab A, n = 5) or manual (Lab B, n = 5) apheresis. After storage for 1 day, the PC was filtered through cotton wool before transfusion on one occasion and, on the other occasion, filtered through a standard screen filter before transfusion to the same donor. Five paired studies were performed by each laboratory. Except for a small, but significant reduction in mean platelet size, from 7.3 +/- 1.1 to 6.6 +/- 0.9 microns 3, after cotton wool filtration, no effect of filtration on various tests of in vitro platelet function and morphologic integrity was found. As demonstrated by autologous radiolabeled studies, no effect of cotton wool filtration on platelet viability was found by Laboratory B, while Laboratory A found a slight increase in the percentage of recovery from 59 +/- 4 to 68 +/- 13 percent, and a small reduction in survival, from 8.2 +/- 0.9 to 7.7 +/- 0.5 days after cotton wool filtration (p less than 0.05). Cotton wool filtration was associated with a slight increase in C3a levels found in manual apheresis PCs. Neither laboratory found any effect of cotton wool filtration per se on the recipients' white cell (WBC) counts or C3a and C5a levels after transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Beta-thromboglobulin during normal pregnancy, labor, and puerperium

Platelet activation has been implicated in the pathogenesis of several obstetrical conditions such as preeclampsia and intrauterine growth retardation. Plasma beta-thromboglobulin (BTG) concentration is an index of in vivo platelet activation. The purpose of this study was to establish normal values of plasma BTG during pregnancy, labor and puerperium. Plasma BTG concentrations were determined from 121 uncomplicated pregnant women, 20 women in labor, 20 puerperal women, and a control group of 28 healthy non-pregnant volunteers. There was no significant difference in plasma BTG concentrations between non-pregnant and pregnant women. Gestational age, labor, and puerperium did not affect plasma BTG concentrations.

Stromal composition in bronchogenic carcinomas--morphometric structure analysis

So far little is known about the pathogenesis and development of the stroma in bronchogenic neoplasia. Clinical and radiological findings and morphological pictures of the tumor taken just after resection, don't reveal information about the pathogenesis and duration of the development of the scar tissue. Using an automatic image analyser (Quantimet 720, Imanco) it was possible to do morphometrical studies of bronchial carcinomas. We correlated the quantity of the stromal reaction in bronchial carcinomas to the size and histological type of the tumor. 60 peripheral, completely excised bronchial tumors were studied using post mortem and surgically removed specimens (25 adenocarcinomas, 22 squamous cell carcinomas, 13 oat cell carcinomas). The mesenchyme was studied histologically and morphometrically at the point of largest circumference of the tumor. Different histological stains were used to identify and correlate epithelial, mesenchymal and necrotic parts of the tumor. Adenocarcinomas on average have 48% stromal composition and even tumors sized 1.5-3 cm2 show evidence of extensive scar tissue. Squamous cell carcinomas have 37% and oat cell carcinomas have 30% fibrous tissue composition. Large adenocarcinomas have less stroma whereas large squamous cell carcinomas showed a relative increase in stromal composition. None of the above was shown in oat cell carcinomas. The amount of stromal tissue therefore depends on the histological tumor type.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma separation using a hollow fiber membrane device

A disposable hollow fiber device was evaluated by collecting approximately 550 ml of normal donor plasma (n = 43) and by performing sham (n = 10) and therapeutic (n = 12) plasma exchanges. Blood was processed at 70 ml per min, and plasma flux averaged 23 (collection) and 25 (exchange) ml per min (mean separation efficiencies of 52 and 60%, respectively). The procedures were tolerated well by all donors and patients. The plasma hemoglobin concentration in separated plasma averaged 1 mg per dl, and cell contamination was negligible (mean of 1, 3, and 6 RBCs, platelets and WBCs/microliter, respectively). There was no evidence of in vivo classical or alternative pathway complement activation as assessed by total hemolytic complement generation (CH50), alternative pathway hemolytic activity (AP50), C3 conversion, or C5 activation, nor were unexpected changes seen in the results of laboratory tests performed after the procedure. Sieving coefficients during sham plasma exchange averaged as follows: albumin, 1.03; IgM, 1.0, IgG, 1.0; IgA, 0.98; factor V, 1.07; factor VII, 0.89; factor VIII, 1.05; and factor IX, 1.19. The device appears to be useful for separation of cell-free plasma from blood during therapeutic plasma exchange procedures.

Parental behavior and the availability of foods among undernourished inner-city children

This study was designed to identify differences in parental behaviors and the availability of food between undernourished and well-nourished inner-city children of early school age. Children with a constellation of measurements of height below the 25th percentile, midarm muscle circumference below the 50th percentile, and hemoglobin concentration below 11.5 g/dL were considered undernourished. These children were matched with controls having measurements above these levels. The homes of all children were investigated. Families of undernourished children were found to have significantly less variety of nutritious foods requiring preparation by an adult available in the home (P less than .01), to have greater variety of convenience foods of low nutritional value (P less than .01), and to prefer fewer vegetables (P less than .04) and dairy products (P less than .01). The Polansky Child Level of Living Scale showed that mothers of undernourished children were less likely to prepare meals regularly for their children (P less than .05) and that they were less effective in providing general parental support to their children (P less than .03).

Specific antibody response after in vivo antigenic stimulation in systemic lupus erythematosus

Several in vitro studies have demonstrated a polyclonal B cell response to antigenic stimulation in patients with systemic lupus erythematosus (SLE). To determine if this polyclonal response occurs in vivo, 18 patients with SLE were antigenically stimulated with the pneumococcal vaccine Pneumovax . Mean antibody response to immunization was the same in SLE and normal control subjects. Although elevated antibody levels to several viruses were present in SLE subjects preimmunization, these levels did not change postimmunization. Total immunoglobulin levels, immune complex levels, and antiblood group B antibody levels did not change in SLE patients after immunization. Antiblood group A titers rose in both SLE patients and normals due to a media contaminant in the Pneumovax . Thus, SLE patients appear to have a specific antibody response to antigenic stimulation with pneumococcal polysaccharide. Polyclonal activation as seen in vitro in SLE may be more restricted in vivo.

Central auditory processing. VI. Detecting ear dominance by evoked potentials

An electrophysiological method is described for measuring the direction and strength of a subject's ear dominance for pitch using the P3 component of event-related potentials. Results of these experiments reveal that the P3 can be used effectively for these measures in man.

Recognition and surprise alter the human visual evoked response

Event-related brain potentials (ERPs) to colored slides contained a late positive component that was significantly enhanced when adults recognized the person, place, or painting in the photograph. Additionally, two late components change in amplitude, corresponding to the amount of surprise reported. Because subjects received no instructions to differentiate among the slides, these changes in brain potentials reflect natural classifications made according to their perceptions and evaluations of the pictorial material. This may be a useful paradigm with which to assess perception, memory, and orienting capacities in populations such as infants who cannot follow verbal instructions.

Pasteurella multocida. Osteomyelitis following dog bites

Two cases of Pasteurella multocida osteomyelitis occurred following dog bit injuries. Difficulties exist in diagnosis and treatment. The role of P Multocida and other dog mouth flora in the pathogenesis of infectious complications following dog bites is discussed. we urge a flexible antimicrobial approach based on culture results.

The relative effects of health and income on life satisfaction

The relative effects of health and income on life satisfaction were analyzed using data collected in three recent national surveys. Financial situation was a slightly stronger predictor of life satisfaction for persons under age sixty-five, whereas health condition had a stronger impact on the life satisfaction of persons over age sixty-four. An attempt was made to quantify the relative impact of health and income on life satisfaction through an analysis of conjoint influence with contingency tables.

Administration of microaggregate filtered blood using a manual infusion pump

Administration sets containing in-line plastic blood pumps are commonly used to transfuse blood. Flow rates were measured while six units of whole blood and red blood cells were infused through a blood pump administration set coupled to either a large pore 260-micron filter or a 20-micron microaggregate blood filter. Using the same type of blood pump administration system and three units of whole blood, the flow rates achieved by the currently available microaggregate blood filters were compared. Results showed that despite a smaller pore size the 20-micron microaggregate blood filter achieved flow rates that were faster than or equal to those recorded for the larger pore (260-micron) filter. This was attributed to the larger filtration surface area possessed by the smaller pore filter, 140 cm2 versus only 30 cm2 for the 260-micron filter. All of the microaggregate filters studied were able to filter three units of whole blood at flow rates in excess of 80 ml/minute. There was no evidence of blood pump induced hemolysis. We concluded that a manual infusion pump can be used to transfuse microaggregate filtered blood rapidly enough to be acceptable for routine clinical or intraoperative use.

Effect of a new service on women's abortion experience

New South Wales law on abortion was liberalized by judicial interpretation in 1971. This paper describes the characteristics of the first 1007 women attending a free-standing clinic for induced abortion after it opened in 1974. Compared with Census data for New South Wales females of child-bearing age, the sample contained an over-representation of women who were relatively younger at conception, never married, divorced or separated, born outside Australia, of Catholic religious background, and worked as nurses or in factories. In comparison with background information about abortion experience before 1971, the clinic sample appeared to feel less anxiety and distress during the abortion sequence.

Contraceptive practice by women presenting to a free-standing abortion clinic

A study was made of the contraceptive methods practised by the first 1,007 women who presented to the Preterm Sydney Clinic regarding pregnancy termination, after the clinic opened in June, 1974. The women's use of contraception at the time of the conception in particular, and also the women's general contraceptive history are described. These factors are related to social and demographic variables of age, marital status, educational level, occupation, country of birth, and religion. Additional discussion is included on the types of contraception used, the sources of contraceptive knowledge, and the methods chosen to use after the abortion.

Auditory evoked potentials during multichannel selective listening: role of pitch and localization cues

Auditory evoked potentials were recorded from subjects who listened selectively to tone pips arriving over one of three input channels. Their task was to detect occasional target tones of a slightly longer duration. In different runs the three channels were distinguished from one another by (a) pitch cues alone (800, 1,800, and 2,800 Hz), (b) localization cues alone (right ear, midline, ane left ear), and (c) both of these cues conjointly. In all three conditions the direction of attention was reflected in the amplitude of the N1 wave of the evoked potential, which was selectively enhanced to tones in the attended channel; tones in the central channels in the single-cue conditions, however, produced the least N1 lability and were the least discriminable. The N1 wave was interpreted as a sign of an initial stimulus set or filtering mode of selective attention, whereas a subsequent P3 wave was specifically associated with detections of the target stimuli.

Auditory evoked potentials during multichannel selective listening: Role of pitch and localization cues

Auditory evoked potentials were recorded from subjects who listened selectively to tone pips arriving over one of three input channels. Their task was to detect occasional target tones of a slightly longer duration. In different runs the three channels were distinguished from one another by (a) pitch cues alone (800, 1,800, and 2,800 Hz), (b) localization cues alone (right ear, midline, ane left ear), and (c) both of these cues conjointly. In all three conditions the direction of attention was reflected in the amplitude of the N1 wave of the evoked potential, which was selectively enhanced to tones in the attended channel; tones in the central channels in the single-cue conditions, however, produced the least N1 lability and were the least discriminable. The N1 wave was interpreted as a sign of an initial stimulus set or filtering mode of selective attention, whereas a subsequent P3 wave was specifically associated with detections of the target stimuli.

Influence of methodology upon apparent concentrations of antibiotics in tissue

This study compares the diffusion in agar of antibiotics prepared in homogenates of tissue, tissue supernatant fluids, whole serum, and buffer solution. Penicillin, erythromycin, cephalothin, gentamicin, and colistin sulfate were studied. With the exception of erythromycin in supernatant fluid of human tonsil, zones of inhibition in agar were consistently smaller in homogenate and supernatant fractions of tissue than in serum and buffer. Thus, a significant error of underestimation occurred when a buffer standard curve was used for assaying antimicrobial activity in homogenates of tissue. This error ranged from 23 to 66% in 10% guinea pig liver homogenate and from 43 to 78% in 20% liver homogenate. A similar, but smaller error of under-estimation resulted with supernatant fractions of tissue except with erythromycin, for which a 25 to 56% error of overestimation occurred when activity in supernatant fraction of tonsil was read off a buffer standard curve. These results emphasize the importance of preparing the standard antibiotic curve with material having agar diffusion properties similar to those of the material being assayed.