Immunological changes in normal pregnancy.

During pregnancy the mother must tolerate intra-uterine allogenic fetal tissue. Failure of this tolerance may cause spontaneous abortion. The immunological changes occurring in normal pregnancy are poorly understood. The aim of this study was to investigate the immunological changes occurring in pregnancy. Thirty women in the first trimester; 10 in the second and 10 in the third trimester of pregnancy were studied and compared to age matched non-pregnant controls. In normal pregnancy there was an increase in the total white cell count with no change in the lymphocyte count. There was a fall in total T cell numbers and activated T cell numbers, with no change in helper/inducer or suppressor/cytotoxic T cell numbers. [3H]Thymidine uptake in response to three different mitogens was increased. This implies an increase in potential for the cells to respond to mitogens. There was no change in interleukin-2 receptor levels, suggesting that despite this increased potential there was no general activation of the immune system. A rise in IgM and IgG was found after mitogen stimulation of peripheral blood lymphocytes, suggesting an increase in potential antibody production. These results demonstrate that lymphocytes from pregnant women have an increased potential rather than an increased activity.     

A quantitative analysis of eye movements during the cover test – a preliminary report

The aim of this study was to carry out quantitative analyses of eye movements during the cover test on a group ( n = 57) of asymptomatic emmetropes. Eye movements were recorded during an automated cover test while subjects fixated a distance (3.4 m) and near (0.4 m) target. There was a significant difference between the amplitude of phoria measured after 2 s of occlusion compared to 10 s ( P < 0.01). The mean phoria after 10 s of occlusion was 0.1° (eso) for distance fixation and 1.6° (exo) for near fixation. The distribution was approximately normal for both distance and near fixation but the standard deviation was greater for near (2.0°) than distance fixation (1.4°). The pattern of eye movements during the recovery phase was more complex than is often assumed, in many cases consisting of a variety of saccadic and vergence movements involving both the covered and 'fixing' eye. The latency of the first recovery movement was significantly shorter for exophoric than esophoric deviations ( P < 0.01) and the latency of some recovery movements were very short (< 150 ms).     

A preliminary study of PDA-based dietary self-monitoring in hemodialysis patients

OBJECTIVE: The purpose of this study was to pilot test an intervention to enhance the adherence of study participants to the hemodialysis dietary regimen. DESIGN: A single case study design was used to examine the potential effectiveness of the intervention over a 4-month period of time. SETTING: A dialysis center in southwestern Pennsylvania. PATIENTS: Of the five individuals entered into the study, one was male and four were female, four were black, and one was white. Participants were 63 to 70 years of age, and had been receiving dialysis for a median of 36 months (range, 18 to 84 months). INTERVENTION: The intervention included counseling to enhance self-efficacy, by a renal dietitian, paired with personal digital assistant-based dietary self-monitoring. Participants met twice per week with interventionists during the first 6 weeks, weekly during the second 6-week period, and biweekly in the final 4-week period. MAIN OUTCOME MEASURES: Monthly laboratory data regarding serum albumin, potassium, and phosphorus levels; Kt/V; and data on average monthly interdialytic weight gain were abstracted from the participants' medical records. C-reactive protein level was determined at baseline and at 4 months. RESULTS: Four of five study participants had an increase in serum albumin level from baseline to their final measurement, and one participant maintained a stable albumin level. Four of five participants also experienced a small increase in serum phosphorus level. Mixed results were obtained with regard to serum potassium and average monthly interdialytic weight gain. CONCLUSIONS: Because of the small sample and single case study design, caution must be used in drawing firm conclusions from this study. Data suggest that the intervention may result in improved dietary intake and improved serum albumin levels. With increased dietary intake, serum phosphorus levels may increase. Additional research is needed to determine the potential efficacy and cost-effectiveness of this intervention for improving dietary adherence.     

Fixation artefact in an intra-operative frozen section: a potential cause of misinterpretation

The intra-operative histological assessment of fresh tissue can provide valuable diagnostic information and guide surgical management, however, even a limited exposure to standard fixation agents can potentially compromise analysis. Defined handling strategies should exist to facilitate the receipt of all specimens, in their optimal state, by the laboratory.     

Effects of diaspirin cross-linked haemoglobin on post-traumatic cerebral perfusion pressure and blood flow in a rodent model of diffuse brain injury

Diaspirin cross-linked haemoglobin (DCLHb) is a new oxygen carrying blood substitute with vasoactive properties. Vasoactive properties may be mediated via high affinity binding of nitric oxide by the haem moiety. Using a rodent model of head injury combined with ischaemia, we studied the effects of DCLHb on cerebral blood flow (CBF) and intracranial pressure (ICP). Twenty anaesthetized rats were allocated randomly to receive treatment with DCLHb 400 mg kg-1 i.v. or placebo (oncotically matched plasma protein substitute 4.5% i.v.). To produce diffusely increased ICP, after a severe weight drop injury, all animals underwent a 30-min period of bilateral carotid ligation combined with a period of induced hypotension. After reperfusion, DCLHb or placebo was infused and the animals instrumented for measurement of intraventricular ICP and CBF in the region of the sensorimotor cortex using the hydrogen clearance technique. Mean arterial pressure (MAP), ICP, cerebral perfusion pressure (CPP) (CPP = MAP - ICP) and CBF were measured 4 h after injury in all animals. DCLHb significantly reduced ICP from mean 13 (SEM 2) to 3 (1) mm Hg (P < 0.001), increased CPP from 52 (8) to 95 (6) mm Hg (P < 0.001) and increased CBF from 21 (2) to 29 (2) ml 100 g-1 min-1 (P = 0.032). We conclude that DCLHb improved CPP without a reduction in CBF in a rodent model of post-traumatic brain swelling.      

Thyroid function tests are rarely abnormal in patients with severe hyperemesis gravidarum

OBJECTIVES: There is considerable controversy in the literature as to the cause of hyperemesis gravidarum. The aim of this project was to measure a range of thyroid hormone levels in a group of hyperemetic pregnant women. PATIENTS: The study was carried out in 10 first trimester pregnant women with hyperemesis gravidarum. All had been admitted to hospital due to the severity of their symptoms. Fifty age matched, healthy first trimester pregnant women were used as controls. MEASUREMENTS: Blood samples from the women were analysed for total T3 (TT3), total T4 (TT4), free T4 (FT4), TSH, thyrotrophin receptor antibodies (TRAb), thyroid stimulating antibodies (TSAb) and thyroid microsomal and thyroglobulin antibodies. Human chorionic gonadotrophin (hCG) levels were also measured. RESULTS: While individual patients were found to have some abnormal thyroid function tests the group as a whole showed no consistent pattern of abnormality and did not differ significantly from a group of healthy first trimester pregnant women. hCG levels were also within the normal range in the hyperemetic patients. DISCUSSION: None of the women in this study received any antithyroid medication and their symptoms improved as the pregnancy progressed. These results would suggest that there is no underlying thyroid abnormality in patients with hyperemesis gravidarum. It would appear that neither thyroid hormones, nor hCG contribute to the pathogenesis of the condition.     

The inhibition of the oxidation of low density lipoprotein by (+)-catechin, a naturally occurring flavonoid.

(+)-Catechin inhibited the copper-catalysed oxidation of human low density lipoprotein (LDL) in a dose-dependent manner with complete inhibition at 20 micrograms/mL. The flavonoid at a concentration of 50 micrograms/mL also inhibited oxidation of LDL induced by the mouse transformed macrophage J774, human monocyte-derived macrophages and vascular endothelial cells isolated from human umbilical cords. LDL modified by copper-catalysed or cell-induced oxidation was endocytosed and degraded by human macrophages at a much greater rate than native LDL. LDL reisolated from copper or cell incubations in the presence of (+)-catechin was endocytosed and degraded at rates similar to native LDL. (+)-Catechin appeared to inhibit the uptake and degradation by macrophages of cell-modified LDL. The actions of (+)-catechin on cell-induced oxidation of LDL are consistent with the ability of flavonoids of similar structure to inhibit lipoxygenases and with a role for lipoxygenases in cell-induced modification of LDL in vivo.