Transfusion of platelet-rich plasma from the organ donor during cardiac transplantation

STUDY OBJECTIVE

To evaluate whether transfusion of platelet-rich plasma from the organ donor during cardiac transplantation can influence the amount of the needed homologous blood products.

DESIGN

Randomized, controlled study.

SETTING

University hospital.

PATIENTS

16 ASA physical status III patients undergoing orthotopic cardiac transplantation.

INTERVENTIONS

Eight patients received donor plasma, while another 8 patients served as a control group. Blood from the organ donor was acquired during cardiac explantation. Thereafter platelet-rich plasma was separated by plasmapheresis (2400 turns per minute). The plasma was then transfused to the organ recipient at the end of the cardiac transplantation. The control group received a similar amount of albumin 5%.

MEASUREMENTS AND MAIN RESULTS

In the patients who received donor plasma, the platelet count increased significantly from 98,000 +/- 49,000 mm-3 to 123,000 +/- 55,000 mm-3, the postoperative requirement of packed red blood cells (PRBCs) was 5.8 +/- 4.5 units, which was significantly lower as compared to the control group (10.8 +/- 5.9 units).

CONCLUSIONS

Transfusion of platelet-rich plasma from the organ donor to the recipient was confirmed to be feasible, the number of postoperatively transfused PRBCs was reduced.

Empirical approaches for the investigation of toxicant-induced loss of tolerance

It has been hypothesized that sensitivity to low-level chemical exposures develops in two steps: initiation by an acute or chronic chemical exposure, followed by triggering of symptoms by low levels of previously tolerated chemical inhalants, foods, or drugs. The Working Group on Toxicant-induced Loss of Tolerance has formulated a series of research questions to test this hypothesis: Do some individuals experience sensitivity to chemicals at levels of exposure unexplained by classical toxicological thresholds and dose-response relationships, and outside normally expected variation in the population? Do chemically sensitive subjects exhibit masking that may interfere with the reproducibility of their responses to chemical challenges? Does chemical sensitivity develop because of acute, intermittent, or continuous exposure to certain substances? If so, what substances are most likely to initiate this process? An experimental approach for testing directly the relationship between patients' reported symptoms and specific exposures was outlined in response to the first question, which was felt to be a key question. Double-blind, placebo-controlled challenges performed in an environmentally controlled hospital facility (environmental medical unit) coupled with rigorous documentation of both objective and subjective responses are necessary to answer this question and to help elucidate the nature and origins of chemical sensitivity.

Visual contrast sensitivity deficits in Bohemian children

Visual contrast sensitivity (VCS) tests have been used successfully in medical diagnosis and subclinical neurotoxicity detection. This paper reports VCS measurements in three studies of children in the Czech Republic. Study 1 compared children in standard schools and schools for the learning disabled. Studies 2 and 3 compared children in Teplice, an area in which soft-brown coal combustion produced high levels of pollutants (e.g. Hg, As, SO2, NOx, and aromatic hydrocarbons), with children in areas of low air pollution, Znojmo and/or Prachatice. It was hypothesized that in utero exposure to the combustion products disrupted neurological development (Sram, 1991). The VCS test (Stereo Optical Co.) consisted of circular fields containing sinusoidal gratings at 5 spatial frequencies (1.5-18 cycles/degree) and various levels of contrast. Subjects indicated orientation of the gratings by pointing left, up, or right. Visual acuity and VCS were measured in each eye of 74 children in Study 1,327 second-grade children in Study 2, and 426 fourth-grade children in Study 3. Hair samples were collected in Studies 2 and 3 analyzed for Hg and As content. Children attending schools for the learning disabled scored significantly lower than controls on VCS, whereas visual acuity was normal. The deficit was greatest at mid- to high spatial frequency. In Study 2, significant VCS deficits were seen in exposed second-grade children at low to mid-spatial frequency, even though visual acuity was slightly above control level. Regression analyses showed that VCS had no relationship to As, but a significant negative correlation with hair Hg was observed in the exposed district. However, current Hg levels were higher in Prachatice. VCS deficits were not observed in the fourth-grade students of Teplice in Study 3. The results of Study 1 indicated that behavioral VCS testing in field studies is practical in young, non-English speaking children, and suggested that vision may be compromised in learning-disabled children. Studies 2 and 3 indicated that at these levels, current Hg body-burdens are poor predictors of VCS. If the VCS deficits seen in Study 2 were related to prenatal exposures, the results of Study 3 suggest that they represent a developmental delay. A longitudinal-study design is needed to address this issue.

Hypothermia accompanied by noncardiogenic pulmonary edema: a case report

The combination of severe hypothermia and noncardiogenic pulmonary edema secondary to an opiate overdose is presented. This case emphasizes the importance of ventilatory support and rewarming techniques available in the emergency department setting.

Teplice program--the impact of air pollution on human health

The aim of the Teplice Program is to investigate and assess the impact of air pollution on the health of the population in the district of Teplice, Czech Republic. Characterization of the air pollutants demonstrated unusually high concentrations during winter inversions of fine particles dominated by acidic sulfates, genotoxic organic compounds, and toxic trace elements. The major source of airborne fine particles is the burning of coal for heating and power. Human exposure and biomarker studies demonstrated large seasonal variations in air pollution within the Teplice District and higher seasonal average pollution levels than the comparative district, Prachatice. Personal exposures to fine particles and organic carcinogens [e.g., polycyclic aromatic hydrocarbons (PAH)] were correlated with excretion of PAH metabolites in urine, several trace metals in blood, and DNA adducts in white blood cells. Respiratory and neurobehavioral studies of school children were conducted using questionnaires and clinical measures. A significantly higher prevalence of adverse respiratory symptoms and decreased lung function were found in the Teplice district than in Prachatice. The neurobehavioral studies indicated significantly higher teacher referrals for clinical assessment in Teplice, but the majority of objective performance measures did not differ. Reproductive studies were conducted in both males and females. A study of the effects of exposure on pregnancy and birth found an excess prevalence of low birth weight and premature births in Teplice; these adverse effects were more common in infants conceived in the winter and whose mothers were smokers. Based on questionnaires and medical examination, the reproductive development of young men was not different between districts and seasons, however, measures of semen quality suggest that exposure to high levels of air pollution are associated with transient decrements in semen quality.

Lymph node biopsy as an aid in the diagnosis of intracranial tuberculosis

This report describes five patients with intracranial tuberculosis (TB): four with tuberculous meningitis and one with intracranial tuberculomas. In all cases the diagnosis was confirmed by excision biopsy of an enlarged cervical or axillary lymph node. The biopsies showed caseating granulomas and acid fast bacilli, confirming the diagnosis of TB within 48 h of admission. Lymphnode biopsies may be an effective and practical aid in diagnosing intracranial TB.

Influence of ascites on the chemotaxis of granulocytes in patients with cirrhosis

Spontaneous bacterial peritonitis is a specific infectious complication in liver cirrhosis. The reasons for the preferred location of infection on the peritoneum are not clear. The aims of the present study were to ascertain whether hepatogenic ascites fluid is chemotactically effective, what part is played by complement factor C3 and whether there are inhibitors of chemotaxis in ascites. Chemotaxis of granulocytes in serum and ascites fluid was measured in 18 patients with cirrhosis and ascites and in 18 healthy individuals using the Boyden chamber method. In the patients, the chemotactic effect of serum was reduced significantly. Ascites fluid had lower chemotactic activity than autologous serum (P < 0.01), directly correlated to C3 levels (P < 0.025). There was a significant correlation between chemotaxis in serum and in ascites fluid (P < 0.005). Adding ascites fluid to serum led to reduction of chemotactic activity only in the patients (P < 0.025). In conclusion, the chemotactic effect of ascites fluid is considerably lower than that of serum and is proportional to local concentrations of C3. Chemotaxis-inhibiting factors can also be identified in ascites fluid, their pathogenetic relevance being limited.

FGF-2 in the MPTP model of Parkinson's disease: effects on astroglial cells

Fibroblast growth factor (FGF) is synthesized and stored by astroglial cells and regulates their proliferation and differentiation in vitro. Its implication in the transformation of quiescent astrocytes into reactive astroglia has been discussed. Using a mouse model of Parkinson's disease, in which FGF-2 has been shown to exert marked neuroprotection of nigrostriatal dopaminergic neurons, we have studied striatal levels of glial fibrillary acidic protein (GFAP), an established marker for astrocytes, and the distribution and morphologies of GFAP-immunoreactive cells following treatments with the neurotoxic drug 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), the growth factor FGF-2, and the non-trophic control protein cytochrome C (cyt C). Systemic injections of MPTP (30 mg/kg) on 3 consecutive days, which we have previously shown to cause profound and long-lasting damage to the nigrostriatal system, induced an approximate 20% transient increase in striatal GFAP, determined by enzyme-linked immunosorbent assay (ELISA), 1 day after the final MPTP injection (= day 4), with subsequent normalization at day 7, which lasted until the end of the experiment (day 18). Morphologically, MPTP elicited a marked increase in number, size, arborization, and stainability of GFAP-immunoreactive cells at day 4 in a striatal area adjacent to the corpus callosum, which was evaluated throughout all experiments. Even on day 18, astrocytes were still apparently larger and more branched than in unlesioned controls. Administration of 4 micrograms of either FGF-2 or cyt C (soaked into a piece of Gelfoam unilaterally to the right striatum in either MPTP- or saline-injected controls) increased striatal GFAP levels bilaterally about 2- to 2.5-fold at 14 days, when FGF-2 showed marked protection of dopaminergic parameters. Likewise, GFAP immunocytochemistry revealed increased numbers of intensely immunoreactive astrocytes under any experimental situation. Differences in the morphologies of astrocytes in FGF-2- and cyt C-treated animals were very subtle and only noted at greater distances away from the site of application of the factors. We conclude that FGF-2, a potent neurotrophic factor for the neurotoxically lesioned nigrostriatal system, does not cause a marked astrogliotic reaction, which might be expected from previous in vitro and in vivo studies in other neural systems. This may limit concerns regarding potential applicability of FGF-2 to the parkinsonian striatum.

FGF-2 modulates dopamine and dopamine-related striatal transmitter systems in the intact and MPTP-lesioned mouse

Following a previous study in which we showed ameliorative effects of basic fibroblast growth factor (FGF-2) locally applied to the nigrostriatal system in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned mice, we investigated FGF-2 actions at different time intervals after the lesion and effects on non-dopaminergic striatal transmitter systems. A triple intraperitoneal injection of 30 mg/kg MPTP at 24 h intervals caused a reduction of striatal dopamine to 23% of control levels that lasted for at least 4 weeks. Four micrograms FGF-2 soaked into gel foam and placed onto the right striatum partially and bilaterally restored dopamine levels and tyrosine hydroxylase activity after 2 weeks, when the treatment started simultaneously or 1 day after the toxin lesion. FGF-2 was ineffective, if administration commenced with a delay of 7 days. Striatal neurotransmitters that are known to be linked to the dopaminergic system were also altered by the MPTP treatment. GABA was significantly increased, while somatostatin levels were reduced. Upon FGF-2 administration both GABA and somatostatin levels were partially normalized. Our data are consistent with the notion that FGF-2 protects and rescues acutely and subacutely MPTP-lesioned nigrostriatal neurons and that its effects must be mainly indirect. Likewise, positive effects of FGF-2 on non-dopaminergic neurons may be due to the partial restoration of striatal dopamine.

FGF-2-mediated protection of cultured mesencephalic dopaminergic neurons against MPTP and MPP+: specificity and impact of culture conditions, non-dopaminergic neurons, and astroglial cells

The protective role of basic fibroblast growth factor (FGF-2) for 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)- and methylpyridiniumion (MPP+)-lesioned dopaminergic (DAergic) nigrostriatal neurons was studied, using dissociated cell cultures of embryonic day (E) 14 rat mesencephalon. Cells were grown in different culture media and received FGF-2 (5 ng/ml) and/or the toxins (5 microM) at various schedules, but were consistently allowed to differentiate for 3 days prior to becoming exposed to the toxin. Survival of tyrosine hydroxylase (TH)-immunoreactive cells at 7 days was only markedly impaired by MPTP, if horse serum (HS) or bovine serum albumin (BSA) were omitted from the culture medium. FGF-2 increased the number of TH-immunoreactive cells, and this increase was not diminished by MPTP under any culture condition. Uptake of 3H-DA was significantly reduced by MPTP in HS- and BSA-containing, but not in protein-less cultures. A protective effect by FGF-2 was only seen in the presence of BSA. MPP+ caused a more pronounced reduction in 3H-DA uptake than MPTP, and this effect was partially reversed by the addition of FGF-2, unless cultures contained HS. Neurofilament protein (NF), and indirect measure for the total number of neurons present in the cultures, was not significantly reduced by MPTP or MPP+ corroborating the specificity of the toxin for DAergic neurons, which constitute only a minor fraction in these cultures. In line with the wide spectrum of target neurons of FGF-2, this factor significantly increased NF contents under any culture condition. Quantification of the amounts of glial fibrillary acidic protein (GFAP) revealed stimulatory effects of FGF-2 (2.5- to 4-fold) and at least 10-fold higher levels in the presence as compared to the absence of HS. These data show that FGF-2 can protect DAergic neurons against MPTP- and MPP(+)-mediated damage. However, the effects of the toxins as well as of FGF-2 are partially dependent on culture conditions. Variations in the effectiveness of toxins and FGF-2 are not overtly related to the total numbers of neurons or astroglial cells, but may reflect culture type-dependent alterations of neuronal and glial metabolism.

Lead and minor hearing impairment

We examined data recorded for 3,545 subjects aged 6-19 y who participated in the Hispanic Health and Nutrition Survey. We sought to confirm a relationship between blood lead levels and elevated hearing thresholds that we previously reported in a similar study in which data from the Second National Health and Nutrition Examination Survey was used. Lead was associated with an increased risk of hearing thresholds that were elevated above the standard reference level at all four frequencies (i.e., 500 Hz, 1,000 Hz, 2,000 Hz, and 4,000 Hz). Lead was also associated with hearing thresholds when they were treated as a continuous outcome. The relationships appeared to continue at blood lead levels less than 10 micrograms/dl. An increase in blood lead, from 6 micrograms/dl to 18 micrograms/dl, was associated with a 2-dB loss in hearing at all frequencies, and an additional 15% of children had hearing thresholds that were below the standard at 2,000 Hz.

Neurobehavioral and sensory irritant effects of controlled exposure to a complex mixture of volatile organic compounds

Subjective reactions of discomfort, impaired air quality, irritation of mucosal membranes, and impaired memory have been reported in chemically sensitive subjects during exposure to volatile organic compounds (VOCs) found in new buildings. Sixty-six normal healthy male subjects aged 18-39 were exposed for 2.75 hr to a complex VOC mixture at 0 and 25 mg/m3. Each subject completed control and exposure sessions at one-week intervals in counterbalanced order. Measurements included comfort ratings of eye, nose and throat irritation, symptom questionnaire and computerized behavioral tests. Subjects found the odor of VOCs unpleasantly strong and reported that VOC exposure degraded air quality, increased headache and produced general discomfort. VOC exposure did not affect performance on any behavioral tests.

Basic FGF reverses chemical and morphological deficits in the nigrostriatal system of MPTP-treated mice

The specific mechanisms underlying the restorative effects of adrenal chromaffin grafts in experimental parkinsonism are still obscure. Recent findings indicated an involvement of graft-induced trophic interactions in the course of recovery-related events. Evidence that basic fibroblast growth factor (bFGF), a potent trophic protein for neurons, (1) is present in chromaffin cells (Blottner et al., 1989) and (2) exerts trophic activities on embryonic mesencephalic neurons in vitro (Ferrari et al., 1989) provided the rationale for administering bFGF in gel foam implants unilaterally to the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) lesioned mice. Simultaneous bFGF/MPTP treatment diminished bilaterally the reduction of striatal dopamine (DA) levels observed in cytochrome c/MPTP-treated mice and led to an ipsilateral reappearance of tyrosine hydroxylase (TH)-like immunoreactive fibers, most notably adjacent to the implant, 2 weeks after the surgery. Determinations of TH activities and TH immunoblotting demonstrated that bFGF almost fully reversed the loss of TH activity on either side but restored TH protein more on the ipsilateral than on the contralateral side. Furthermore, differences in dihydroxyphenylacetic acid levels, which were about twice as high on the contralateral side yet still reduced with respect to untreated mice, supported our assumption that the molar TH activity was increased on the untreated side, possibly due to an intrinsic compensatory up-regulation. Delayed administration of bFGF starting 8 d after the MPTP treatment was equally effective with regard to morphological parameters. Our results suggest that bFGF partially prevents the deleterious chemical and morphological consequences of an MPTP-mediated nigrostriatal lesion. Thus, bFGF mimics at least the morphological effects of chromaffin cell grafts to the MPTP-lesioned brain.

A role of basic fibroblast growth factor for rat septal neurons

The in vitro and in vivo relevance of basic fibroblast growth factor (bFGF) for rat septal neurons was studied and compared with the effects of nerve growth factor (NGF). Implantation of gel foam soaked with saline, NGF or bFGF following fimbria fornix (FF) transection in adult rats showed that after 4 weeks the neuronal death in the medial septum of saline-treated rats (87% as compared to the unlesioned side) was reduced by NGF- or bFGF-treatment (NGF 0.3 micrograms: 71%; NGF 20 micrograms: 54%; bFGF 8 micrograms: 68%). These results indicate that both NGF and bFGF are able to sustain neurons in the medial septum after FF transection. Moreover, choline acetyltransferase (ChAT)-immunocytochemistry revealed that rescued neurons comprise a large proportion of the cholinergic population. In cultured embryonic rat septal neurons seeded at high densities both NGF and bFGF significantly enhanced ChAT activity (7.5- and 3-fold, respectively) without affecting cell survival. In low density cultures both neurotrophic proteins increased the survival after 4 days. The portions of cholinergic and GABAergic neurons did not change after NGF- and bFGF-treatment (acetylcholinesterase cytochemistry, anti-GABA immunocytochemistry). These results show that i) NGF and bFGF promote survival of embryonic septal cholinergic and GABAergic neurons and may enhance ChAT activity, and ii) bFGF is a potent trophic factor for septal neurons in vivo and in vitro.

Basic fibroblast growth factor and nerve growth factor administered in gel foam rescue medial septal neurons after fimbria fornix transection

Basic fibroblast growth factor (bFGF) recently has been established as a survival- and transmitter-promoting neurotrophic agent for embryonic neurons in vitro. Its local application to lesioned adult optic and sciatic nerves has been shown to rescue axotomized retinal and sensory neurons that otherwise die. Following transection of the fimbria fornix pathway connecting the medial septum (MS) to the hippocampus, MS neurons undergo severe cell death, which can be prevented partially by infusion of nerve growth factor (NGF). In the same lesion paradigm, we find that 87% of these neurons visualized by cresyl-violet staining have disappeared by 4 weeks after unilateral fimbria fornix transection in adult rats. Implantation of gel foam soaked with 8 micrograms bFGF reduced neuron death to 68%. A similar rescue effect was seen with 0.3 microgram NGF. NGF administered at 20 micrograms reduced cell losses to 54%. Thus, bFGF rescued 22% and NGF at 20 micrograms 38% of the neurons that otherwise would have died. Choline acetyltransferase immunocytochemistry revealed dramatic losses of cholinergic neurons on the lesioned, compared with the unlesioned, side. Cholinergic neuron death was clearly reduced by the bFGF and NGF treatments. Basic FGF, in contrast to NGF, did not prevent a reduction in size of surviving neuronal cell bodies. Considered in the context of FGF being present in brain and hippocampal neurons, our results suggest a possible role for FGF as a neurotrophic factor for CNS neurons in vivo.

Basic fibroblast growth factor promotes in vitro survival and cholinergic development of rat septal neurons: comparison with the effects of nerve growth factor

The effects of basic fibroblast growth factor and nerve growth factor on survival and transmitter expression of cultured rat embryonic (E18) septal neurons were studied. Two different culture media were used: (i) a horse serum-containing Leibowitz L-15 medium and (ii) a serum-free N1-supplemented Dulbecco's modified Eagle's medium. Addition of basic fibroblast growth factor to either culture medium enhanced neuronal survival in low density cultures after 4 days. The effects of basic fibroblast growth factor were dose-dependent and blocked by anti-basic fibroblast growth factor antibodies. In serum-containing L-15 medium nerve growth factor also promoted neuronal survival. Basic fibroblast growth factor and nerve growth factor supported neurons comprised both cholinergic and GABAergic subpopulations. The effects of basic fibroblast growth factor and nerve growth factor were not additive. In high density cultures using serum-containing L-15 medium survival of septal neurons was four times higher than in low density cultures after 4 days. Addition of basic fibroblast growth factor or nerve growth factor did not further augment neuronal survival in high density cultures. Maintenance of septal neurons at high density was not affected by antibodies to basic fibroblast growth factor and/or nerve growth factor. Addition of basic fibroblast growth factor or nerve growth factor to serum-containing L-15 medium at high cell density significantly enhanced choline acetyltransferase activity 3- and 7.5-fold, respectively, without affecting cell survival. In conclusion, next to nerve growth factor, basic fibroblast growth factor, which has been located in the hippocampal target area of septal neurons, appears to be another potent trophic factor for septal neurons.

Electrophysiological measures of visual and auditory function as indices of neurotoxicity

The application of auditory and visual evoked potentials (VEP) to neurotoxicity testing of humans and animals is reviewed. VEPs elicited by flash, reversing-checkerboard patterns, and sine wave grating are described. The flask evoked potential in rats is altered by exposure to many heavy metals, pesticides and solvents. The brainstem auditory evoked potential also appears to be sensitive to neurotoxic chemicals, but the evidence available is limited. The homology of auditory and visual evoked potentials in rats and humans is useful for cross-species extrapolation in neurotoxicology research.

Pharmacological effects of nerve growth factor and fibroblast growth factor applied to the transectioned sciatic nerve on neuron death in adult rat dorsal root ganglia

Sciatic nerve transection performed on adult rats caused neuronal losses after 4 weeks in the L4-6 dorsal root ganglia (DRG) of 35% as compared to the unlesioned side. Nerve growth factor (NGF) administered at a single dose of 6000 Biological Units in silicone tubes fixed to the proximal nerve stump completely prevented these cell losses. Basic fibroblast growth factor (bFGF) also protected DRG neurons, but at the concentrations applied (6000 Trophic Units, tested on embryonic chick ciliary ganglion neurons), failed to maintain cell numbers identical to unoperated side. Our data indicate that NGF and bFGF protect adult sensory neurons from lesion-induced death. Preliminary results suggest that local accumulation of neurotrophic activities at the proximal nerve stump elicited by NGF and, possibly bFGF, might be involved in the beneficial effects of these proteins on the maintenance of axotomized sensory neurons.