Acute leukaemia in Jehovah''s Witnesses

The bioavailability of iron glycine added to a vegetable infant weaning food was compared with ferrous sulfate. Stable, isotopically labeled compounds (57Fe or 58Fe) were mixed into the midday meal (1.4 mg added Fe/serving) and fed to 9-mo-old infants on alternate days for 8 d. Bioavailability, expressed as a percentage of the dose consumed, was measured from isotopic enrichment of hemoglobin 14 d after the last test meal. There was no difference between iron glycine and ferrous sulfate (x+/-SEM): 9.0+/-0.7% and 9.9+/-0.8%, respectively. The effect of chelation was examined by measuring iron bioavailability of iron glycine and ferrous sulfate added to a high-phytate (310 mg/100 g) whole-grain cereal weaning food and comparing it with a lower-phytate (147 mg/100 g) vegetable food, as used in the first study. Both iron compounds had lower bioavailability from the high-phytate food, 5.2+/-0.5% for iron glycine and 3.8+/-0.9% for ferrous sulfate, than the lower-phytate food, 9.8+/-1.5% for iron glycine and 9.1+/-1.3% for ferrous sulfate. The results showed no significant difference in bioavailability between the two forms of iron when added to infant weaning foods, suggesting that the glycine complex was fully or partially dissociated in the gastrointestinal tract. It is concluded that chelation does not improve the bioavailability of iron in the presence of dietary inhibitors.     

Pion-nucleus single charge exchange induced by stopped negative pions

The early genotoxic action of oral exposure to UICC crocidolite asbestos fibres was studied in different short-term tests. Fischer-344 rats were gavaged with 50 mg/b.w.kg untreated asbestos fibres and fibres which had been allowed to adsorb benzo(a)pyrene molecules from extremely low concentration (0.25-2.5 microg/ml) aqueous solutions. This system can be considered a model for the drinking of potable water contaminated by asbestos fibres together with biologically active organic micro-pollutants. The Ames Salmonella mutagenicity assay was performed on concentrated urine and serum samples of treated animals. The formation of micronuclei and sister chromatid exchanges was also studied in the bone marrow of the exposed rats. The micronucleus analysis indicated marginal genotoxic activity only upon treatment with crocidolite prepared from the solution of 1 microg/ml. A dose-dependent increase was, however, demonstrated in the sister chromatid exchange frequency upon treatment with benzo(a)pyrene coated fibres. These experiments suggest the acute cogenotoxic activity of such fibres in orally exposed animals.     

Trigeminal neuralgia. A retrospective survey of a sample of patients in Singapore and Malaysia

We report a case of synovial sarcoma with extensive myxoid change diagnosed by fine-needle aspiration. The patient is a 46-year-old woman who presented with a right paratibial mass. Aspiration cytology demonstrated a spindle cell neoplasm consistent with a synovial sarcoma but containing a prominent myxoid matrix. The clinical suspicion and cytologic diagnosis of a synovial sarcoma was confirmed by histologic and immunohistochemical findings. The cytologic differential diagnosis of spindle cell neoplasms with extensive myxoid change should be broadened to include synovial sarcoma.     

In-situ forces in the human posterior cruciate ligament in response to posterior tibial loading

The presence of human cytomegalovirus (HCMV) DNA in liver, spleen, and kidney samples of HCMV-seropositive trauma victims during latency was demonstrated by polymerase chain reaction (PCR), using primers reactive with the major immediate early gene exon 4 and the structural gene pp150. Sequence analysis of the PCR amplificates showed more than 95% homology with the reference HCMV strain AD169. The few mutations observed were mostly distributed randomly. In one subject two types of the MIE-4 gene were detected, and in another subject two types of the pp150 gene were found, suggesting that different strains of HCMV can be found in organs of the same patient during latency.     

The investigation of chronic constipation for surgical management

Organic solvents, such as ethanol or dimethyl sulphoxide (DMSO), have been used in liquid embolic agents. To investigate the effects of these solvents on the cerebral blood vessels and cerebral tissue, we subjected Wistar rats weighing 250-300 g to internal carotid artery infusion of 0.2 ml diluted ethanol (10%, 40% or 70%) or anhydrous DMSO (100%). Some rats were sacrificed 5 min after the infusion and the remainder at 10 days. Rats injected with ethanol at high concentration or DMSO showed extensive exudation of Evans blue at the site of injection 5 min after infusion, together with full-thickness necrosis of the wall of vessels and swelling of brain cells. In contrast, rats injected with 10% or 40% ethanol solution showed necrosis of only the intimal layer and partial necrosis of the medial layer and no brain swelling was observed. These findings suggest that ethanol at low concentration can be used as a relatively safe solvent for liquid embolic substances.     

Endogenous substance P inhibits the expression of corticotropin-releasing hormone during a chronic inflammatory stress

We have investigated the effects of a chronic inflammatory stress on substance P (SP) levels in the hypothalami of rats given adjuvant-induced arthritis (AA). Fourteen days after injection of Mycobacterium butyricum, substance P concentrations in the paraventricular nucleus (PVN) and median eminence/arcuate nucleus were significantly increased. In AA rats injected intraperitoneally with the specific neurokinin-1 receptor antagonist RP67580, plasma ACTH and corticosterone concentrations were significantly elevated, and corticotropin-releasing hormone (CRH) mRNA in the PVN was increased compared to the AA group which received saline alone. The increases in hypothalamic SP in AA, together with the data demonstrating that HPA axis activity is enhanced in AA following injection of a SP antagonist, are consistent with the hypothesis that SP is acting as an inhibitor of CRH expression in this model of chronic inflammatory stress.     

Analytical and clinical relationships between human IgG autoantibodies to beta 2 glycoprotein I and anticardiolipin antibodies

OBJECTIVE: To examine IgG anti-beta 2 glycoprotein I (anti-beta 2 GPI) binding in 82 sera referred for anticardiolipin antibody (aCL) testing and to develop preliminary clinical correlations with antiphospholipid syndrome (APS). METHODS: Immunoassay of IgG cofactor dependent aCL and IgG anti-beta 2 GPI antibodies and retrospective chart review. RESULTS: Forty-four sera exhibited normal (< or = 22 GPL units) aCL activity, 18 had moderate binding activity (23-45 GPL units), and 20 had high (> or = 46 GPL units) binding activity to cardiolipin. Among these groups, 6 of the 20 sera in the high GPL group had elevated anti-beta 2 GPI. This correlated strongly with 2 or more clinical manifestations of APS. CONCLUSION: Anti-beta 2 GPI activity may be a more valuable indicator of APS than aCL.     

Preimplantation alteration of adenine nucleotides in cryopreserved heart valves

To assess the initial metabolic phase of cellular injury from cardiac valve processing, high-energy phosphate concentrations were analyzed in valve leaflets subsequent to critical processing steps. Using a porcine model, valves were processed in a manner identical to human homografts, with 58 randomly assigned to five groups representing distinct preparation phases. Group I (controls) sustained 40 minutes of warm ischemia concluded by liquid nitrogen immersion. Remaining groups similarly endured 40 minutes of ischemia, but were subsequently prepared according to stepwise design: II, warm ischemia + 24 hours of 4 degrees C ischemia; III, warm ischemia + 24 hours of 4 degrees C antibiotic disinfection; IV, warm ischemia + 24 hours at 4 degrees C (without antibiotics) + cryopreservation (-1 degrees C/min cryoprotected freezing); and V, warm ischemia+disinfection+cryopreservation. At each regimen's conclusion leaflet extracts were assayed by high-performance liquid chromatography for high-energy adenine nucleotides (adenosine triphosphate, adenosine diphosphate, adenosine monophosphate) and catabolites. A 47% and 86% decrease in cellular adenosine triphosphate level was observed in group III and group V leaflets, respectively. The level of total adenine nucleotides was maintained up to cryopreservation; thereafter a 74% decrease was noted. Catabolite analysis confirmed incomplete degradation of adenine nucleotides indicating cellular metabolic resilience throughout standard homograft preparation in valves previously exposed to 40 minutes of warm ischemia.     

Mitochondrial free calcium regulation in hypoxia and reoxygenation: relation to cellular injury

The role of mitochondria in myocardial ischemic and hypoxic injury is discussed. Increases in mitochondrial Ca content and ionized Ca2+ concentration are observed during and after ischemic and hypoxic exposure and have traditionally been considered to impair mitochondrial function. New data are discussed in which it is shown that increases in mitochondrial [Ca2+] do not necessarily reflect irreversible myocyte injury. Further, it is shown that irreversible cellular injury may occur in hypoxic myocytes in association with increases in mitochondrial [Ca2+] that would ordinarily be considered to fall within a physiologic range. The significance of these observations is considered in context with observations relating to the assessment of post-hypoxic mitochondrial function.