Aortic embolism of cement: a rare complication of lumbar percutaneous vertebroplasty

An aortic embolus of cement occurred in a 72-year-old woman after lumbar percutaneous vertebroplasty for breast cancer metastasis. A CT scan during the procedure revealed cement migration into the aorta via the lumbar artery. The cement embolus in the aorta, along with the hook-shaped cement fragment in the lumbar artery, was asymptomatic. Thereafter, a CT scan 4 months later still showed the presence of cement in the aorta and the lumbar artery at the level of the vertebroplasty. The patient is free of complaints after 4 months without anticoagulant treatment. This rare complication occurred because the collateral arterial supplies to the breast metastasis and the retrograde migration of cement during the vertebroplasty were not recognized. Proper techniques can minimize the risk of arterial embolism caused by cement during the procedure.     

The cytotoxicity of iodinated radiocontrast agents on renal cells in vitro

A deterioration of renal function is one preoccupying complication of iodinated radiocontrast agents in clinical practice. These compounds have direct toxic effects on renal cells, which are only in part related to their physicochemical properties. The hyperosmolal monomeric ionic radiocontrast agents, like diatrizoate, have the highest toxicity, whereas renal cells are less affected by (nonionic) compounds with reduced osmolality. The toxic effects include cellular energy failure, a disruption of calcium homeostasis, a disturbance of tubular cell polarity and programmed cell death (apoptosis). The molecular mechanisms of the direct cytotoxicity are still unclear, although oxidative stress has been implicated. Radiocontrast cytotoxicity has been demonstrated in glomerular mesangial cells and in renal epithelial cells in vitro. In vivo, the direct cellular toxicity of radiocontrast agents is compounded with alterations in blood flow and/or viscosity, ultimately resulting in renal medullary hypoxia, which is a hallmark feature of the complex clinical syndrome of radiocontrast nephropathy.     

Organ donation and transplant: The Islamic perspective

Islam is the second most practiced religion globally, and the number of Muslims in Western countries has been increasing due to recent trends in migration. Studies have shown that Muslims in the Western world have more negative attitudes toward organ donation and transplantation compared with individuals from other religious backgrounds. Multiple barriers have been postulated that may prevent Muslims from exploring organ donation or transplantation. We conducted a literature review with the goal of summarizing the opinions of major Sunni and Shia scholars and Islamic bodies about organ donation and transplantation, including their opinions and rulings on the neurological determination of death to inform healthcare professionals, community members, and leaders. We also identified factors and attitudes that may prevent members of the Muslim community from achieving equitable access to transplantation or from consenting to donate organs during life or after death. Key factors or concerns identified included: lack of information regarding organ donation, mistrust of the healthcare system, family opinions, sacredness of the body, lack of clear understanding of religious rulings, and opinions of religious leaders. Studies have suggested that partnering with religious leaders to address these concerns may help foster positive attitudes toward organ donation and transplantation.     

Molecular genetics of PKU in Eastern Europe: A nonsense mutation associated with haplotype 4 of the phenylalanine hydroxylase gene

Phenylketonuria (PKU) is a genetic disorder secondary to a deficiency of hepatic phenyalanine hydroxylase (PAH). Several mutations in thePAH gene have recently been reported, and linkage disequilibrium was observed between RFLP haplotypes and specific mutations. A new molecular lesion has been identified in exon 7 of thePAH gene in a Hungarian PKU patient by direct sequencing of PCR-amplified DNA. The C-to-T transition causes the substitution of Arg²⁴³ to a termination codon, and the mutant allele is associated with haplotype 4 of thePAH gene. The mutation is present in two of nine mutant haplotype 4 alleles among Eastern Europeans and is not present among Western Europeans and Asians. The rarity of this mutant allele and its restricted geographic distribution suggest that the mutational event occurred recently on a normal haplotype 4 background in Eastern Europe.     

The Effect of Small Variation of the Frequent Auditory Stimulus on the Event-Related Brain Potential to the Infrequent Stimulus

We investigated whether the mismatch process between a rare stimulus and the trace of frequent stimulus, which generates the mismatch-negativity component of the event-related potential, can tolerate a small variation in the intensity of the frequent stimulus. Series of short tone pips were presented to 10 subjects while they were reading a book and ignoring the auditory stimuli. The intensity (mean 80dB) of the frequent stimulus (600 Hz) varied within a range that was different in different blocks. The probability of the infrequent stimuli which were, in different blocks, either intensity deviants (600 Hz/70dB) or frequency deviants (650 Hz/80dB) was 10%. Both deviant stimuli elicited mismatch negativity even when the intensity of the frequent stimulus varied, although the amplitude of this component decreased with the increasing variability of the frequent stimulus. These results show that the generator process of mismatch negativity tolerates some variation in the repetitive stimulus, thus indicating that this process is also activated in ecologically more valid conditions. This is crucial to the interpretation of the generator process of mismatch negativity as a biologically vital warning mechanism.     

The TNF-derived TIP peptide activates the epithelial sodium channel and ameliorates experimental nephrotoxic serum nephritis

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Red cell distribution width is associated with mortality in kidney transplant recipients

Background

Red cell distribution width (RDW), a parameter routinely reported as part of the complete blood count, is associated with increased morbidity and mortality risk in different patient populations. No published data are available about the association between RDW and mortality in kidney transplant recipients.

Methods

We collected socio-demographic, clinical parameters, medical and transplant history and laboratory data at baseline in 723 prevalent kidney transplant recipients between June and October 2008 [mean age 51 ± 13 (SD) years, 56 % men, 21 % diabetics]. Associations between baseline RDW values and all-cause mortality over 3 years were examined in unadjusted and adjusted models.

Results

Increasing RDW was associated with increased mortality in both unadjusted [(HR_{1 % increase} = 1.63; 95 % CI 1.41–1.89) and (HR_>median = 2.74; 95 % CI 1.68–4.48)] and fully adjusted models [(HR_{1 % increase} = 1.60; 95 % CI 1.27–1.89) and (HR_>median = 1.33; 95 % CI 0.76–2.35)]. In reclassification analyses, RDW improved the predictive value of all-cause mortality prediction models [the net reclassification improvement (NRI) was 0.189; p < 0.001].

Conclusions

RDW, a cheap and readily available but largely neglected parameter independently, predicts mortality in prevalent kidney transplant recipients and could potentially been used in everyday risk assessment of kidney transplant recipients.     

Treatment of End-Stage Renal Disease in Central and Eastern Europe: Overview of Current Status and Future Needs

The situation of end-stage renal disease (ESRD) patients in central and eastern Europe was very poor for many years during the so called socialistic era. Economical and political liberation resulted in the significant growth of renal replacement facilities in this region. The number of hemodialysis units increased significantly (56%) during the period 1990–1996, and the number of patients treated with this modality has risen by 75%. More dramatic progress was achieved in peritoneal dialysis. The number of units performing this method of renal replacement therapy (RTT) increased by 277% and the number of patients by more than 300%. Not only quantitative but also qualitative changes were observed. More modern hemodialysis machines installed in the vast majority of units allow for the performance of bicarbonate dialysis, controlled ultrafiltration, and sodium profile modeling. Also, a wider choice of biocompatible dialyzers has become available during the last few years. The number of centers performing renal transplantation has increased significantly, but the number of renal transplants has not followed this progress. Despite all the progress, further development of all RRT methods is necessary to achieve acceptance rates comparable to those observed in developed countries.     

Recurring transitory blindness caused by primary marginal pigment epithelial iris cysts

PURPOSE: To report four cases of primary pupillary pigment epithelial iris cysts, all members of one family, in which two of the patients had recurring transitory visual impairment. METHODS: Observational case series. History was taken, the patients were examined with slit-lamp and ultrasound biomicroscopy, and surgically removed cyst tissue was examined with transmission electron microscopy. RESULTS: Pupillary pigment epithelial cysts of the iris generally show an autosomal dominant heredity pattern, with occasional lack of penetrance. In two of our cases, the size and location of the cysts caused visual symptoms, necessitating surgical removal. The cyst wall consists entirely of pigment epithelial cells. CONCLUSION: The origin of pupillary pigment epithelial cysts is unclear, and a hereditary background is very likely. Their clinical significance is in their similarity to pigmented tumors of the iris. They may also be indicative of coexisting systemic disease. In symptomatic cases, treatment is indicated.     

Effects of antihistamines on leukotriene and cytokine release from dispersed nasal polyp cells

In this study the effects of antihistamines on the release of eicosanoids and the pro-inflammatory cytokine tumor necrosis factor alpha (TNF alpha) were compared. Enzymatically dispersed cells from human nasal polyps served as an in vitro model of chronic respiratory mucosal inflammation. Nasal polyp cells (2 x 10(5)/ml) were sensitized with human IgE pre-incubated azelastine (CAS 58581-89-8), terfenadine (CAS 50679-08-8), levocabastine (CAS 79516-68-0) or cetirizine (CAS 83881-51-0), and stimulated with anti-human immunoglobulin E (IgE). Thromboxane B2 (TBX2) and leukotriene C4 (LTC4) were measured by radioimmunoassay (RIA), TNF alpha by enzyme-linked immunosorbent assay (ELISA). Data represent mean values of % inhibition estimated from the untreated positive control or mean IC50 (n = 5). Azelastine and terfenadine inhibited TNF alpha release with IC50 values of 6.2 mumol/l and 4.3 mumol/l, respectively. Terfenadine reduced TXB2 release by 37 +/- 15%, and LTC4 release was decreased by azelastine and terfenadine very potently by 86% and 100%, respectively. Azelastine shows anti-inflammatory properties in therapeutically relevant concentrations as assessed by its ability to reduce TNF alpha release as well as its ability to inhibit LTC4 production in allergically stimulated human nasal polyp cells.