New laboratory markers in diagnosis of alzheimer dementia

OBJECTIVES

The aim of our work was to assess the role of tau protein, beta amyloid and cystatin C in diagnosis of Alzheimer dementia (AD) and other neurodegenerative diseases (NDs).

METHODS

The levels of tau protein, beta amyloid and cystatin C were assessed in a set of 79 patients with ND (38 men and 41 women; aged 22-90 years; mean, 61.6 +/- 15.6 years) and in a control group of 79 subjects with a healthy central nervous system (38 men and 41 women; aged 20-91 years; mean, 61.5 +/- 15.1 years).

RESULTS

When compared with the subjects in the control group, a statistically significant decrease in tau protein levels was found in patients with ND, an increase in tau protein levels in patients with AD and an increase in cystatin C cerebrospinal fluid/serum index in the ND + AD group.

DISCUSSION

Our work only confirmed the previously reported results in part. Although tau protein seems to be a quite reliable marker of AD, the role of beta amyloid in AD diagnosis remains at the least questionable. In the case of cystatin C, our results would seem to confirm the views of certain authors that cystatin C will probably not become a new 'revolutionary' marker contributing to differential diagnostics.

[Persistent diarrhoea, hypotension, polyneuropathy]

We present a case report of a 59-year-old man with a history of arterial hypertension and excision of malignant melanoma. He was admitted to the hospital because of two months history of diarrhoea, weight loss and circulatory collapse. In addition, the patient suffered from marked vegetative instability with symptomatic hypotension, polyneuropathy and progression of renal insufficiency, without proteinuria. Complex examination did not reveal neoplasms, endocrine, autoimmune, infectious or neurodegenerative disorders. A serial biopsy of colon failed to provide a clue to the diagnosis. However, AA amyloidosis was found on the kidney biopsy. Neither chronic inflammation nor malignancy was revealed and, hence, no causal treatment could have been established. The patient died from multiple organ failure. The autopsy confirmed systemic AA amyloidosis. The triad consisting ofdiarrhoea, polyneuropathy and hypotension should rise the suspicion on amyloidosis.

Algesthesia after epileptic seizure

The consequences of epileptic seizures related to postictal inhibition in early postictal period include postictal analgesia. We studied this phenomenon over 96 h following flurothyl-induced seizures in adult male Wistar rats. Nociception of control (no seizure) and seizured groups were tested using the plantar and von Frey hair tests. We determined latency of forepaw and hind paw reactions using plantar tests and the number of von Frey hairs reactions. Shortly after seizures, longer plantar test latencies were seen relative to the control group. Before the seizures the plantar test reaction times were significantly shorter in forepaws than in hind paws. The effect disappeared post-seizure and surprisingly, it also disappeared at the corresponding time in controls; it reappeared after 48 h in the seizure group and after 24 h in controls. Differences in the von Frey hairs test occurred at 5 and 60 min post-seizure, however, these differences could not be explained by limb anatomy; although, different thermal and mechanical nociception mechanisms could be significant. The unexpected reactions in controls could be related to brief social and physical interactions between the two groups.

Occurrence of diabetes mellitus in spontaneous intracerebral hemorrhage

The role of diabetes mellitus (DM) in the etiopathogenesis of spontaneous intracerebral hemorrhage (SICH) is controversial. The aim was to assess the role of DM in our SICH patients. In a hospital-based cross-section study, the occurrence of DM prior to a hemorrhagic stroke was observed in 80 SICH patients (44 males, aged 36-87 years, mean 67.1 +/- 11.9 years; 36 females, aged 56-86 years, mean 71.1 +/- 8.3 years), and in a control group (CG) of 80 age- and sex-matched patients with low back pain. All patients were treated at the Departments of Neurology and Neurosurgery, University Hospital, Olomouc, Czech Republic. Two-sample t test and Pearson's homogeneity chi(2) test were applied when assessing statistical significance. DM was found in 37.5% of SICH patients versus 22.5% of CG subjects (P < 0.05). DM occurs significantly more frequently in SICH patients in the Olomouc region of the Czech Republic when compared to the general population.

Population based study of islet cell carcinoma

15103

Background: Little is known about the epidemiology and natural history of islet cell carcinoma. In this study, we examine the epidemiology, natural history, and prognostic factors impacting survival duration for islet cell carcinoma using population based registries. Methods: The Surveillance, Epidemiology, and End Results (SEER) Program database (1973 - 2003 release April 2006) was used to identify cases of islet cell carcinoma using histology codes and tumor site. Results: 1,310 (619 women and 691 men) cases were identified. Median age at diagnosis was 59 years. The annual age-adjusted incidence in the periods covered by SEER 9 (1973–1991), SEER 13 (1992–1999), and SEER 17 (2000–2003) were 0.16, 0.14, and 0.12 per 100,000 respectively. The estimated 28-year limited duration prevalence on January 1, 2003 in the United States was 2,705 cases. Insulinomas (57%), glucagonomas (53%), and VIPomas (64%) were more likely to be located in the tail of the pancreas while gastrinomas were more likely to be located in the head of the pancreas (63%). Classified by SEER stage, localized, regional, and distant stages corresponded to 14%, 23% and 54% of cases. The median survival was 38 months. By stage, median survival for patients with localized, regional, and distant disease were 124 (95% CI, 80–168) months, 70 (95% CI, 54 - 86) months, and 23 (95% CI, 20 - 26) months respectively. By multivariate Cox proportional modeling, stage (P < 0.001), primary tumor location (P = .04), and age at diagnosis (P < 0.001) were found to be significant predictors of survival. Conclusion: Islet cell carcinomas account for approximately 1.3% of cancers arising in the pancreas. Most patients have advanced disease at the time of diagnosis. Despite its reputation of being indolent, survival of patients with advanced disease remains in the range of 2 years. Development of novel therapeutic approaches is needed.

No significant financial relationships to disclose.

Faddeev calculation of a K- pp quasibound state

We report on the first genuinely three-body K[over]NN- piSigmaN coupled-channel Faddeev calculation in search for quasibound states in the K- pp system. The main absorptivity in the K- p subsystem is accounted for by fitting to K- p data near threshold. Our calculation yields one such quasibound state, with I=1/2, J{pi}=0-, bound in the range B approximately 55-70 MeV, with a width of Gamma approximately 90-110 MeV. These results differ substantially from previous estimates, and are at odds with the K- pp-->Lambda p signal observed by the FINUDA collaboration.

Influence of melatonin pretreatment and preconditioning by hypobaric hypoxia on the development of cortical photothrombotic ischemic lesion

Photothrombotic model of ischemia (PT) is based on free radical-mediated endothelial dysfunction followed by thrombosis. Free radicals are also involved in hypoxic preconditioning. We tested the sensitivity of PT to preconditioning with hypobaric hypoxia and to pretreatment with melatonin. In adult Wistar rats, after intravenous application of Rose Bengal, a stereo-tactically defined spot on the denuded skull was irradiated by a laser for 9 min. The first experimental group underwent hypobaric hypoxia three days before irradiation. In the second experimental group, melatonin was applied intraperitoneally one hour before irradiation. Three days after irradiation, animals were sacrificed, the brains perfused, and stained with TTC. Ischemic lesions were divided into grades (I, II, III). In the control group (where no manipulation preceded photothrombosis), most animals displayed deep damage involving the striatum (grade III). The group pre-exposed to hypoxia showed similar results. Only 28.57 % of the melatonin pretreated animals exhibited grade III lesions, and in 57.14 % no signs of lesions were detected. Pre-exposure to hypoxia was not protective in our model. Pretreatment with melatonin lead to a significant reduction of the number of large ischemic lesions. This result is probably caused by protection of endothelial cells by melatonin.

Association of PAX5 expression with clinical outcome in patients with TaT1 transitional cell carcinoma of the bladder

OBJECTIVES

To assess the frequency and intensity of PAX5 gene messenger ribonucleic acid (mRNA) expression in TaT1 bladder cancer tissue, as well as its correlation with clinicopathologic variables and patient outcome.

METHODS

The RNA expression of PAX5 was evaluated with reverse transcriptase polymerase chain reaction in the tumor tissue of 75 patients with stage TaT1 bladder cancer treated with transurethral resection. Patients were observed with cystoscopy and urinary cytologic evaluation. The association between PAX5 expression and clinicopathologic variables and patient outcome was evaluated. Benign urothelium from 8 patients with benign prostatic hyperplasia was obtained. These patients were used as a control group.

RESULTS

PAX5 expression was found in 62 patients with bladder cancer (82.7%) but in no patient from the control group. High PAX5 expression (greater than 0.2) was confirmed in 19 patients (25.3%). No significant relationship was observed between quantity of PAX5 expression and clinicopathologic variables. The 3-year recurrence-free and progression-free survival rates in highly positive patients were 13.2% and 71.6%, compared with 40.6% and 92.8%, respectively, in patients with weak or negative expression (log-rank test, P = 0.0075, P = 0.022). Multivariate Cox proportional hazard model analysis identified PAX5 expression as an independent predictor of tumor recurrence.

CONCLUSIONS

PAX5 gene expression is a frequent finding in superficial transitional cell carcinoma of the bladder. High levels of PAX5 are associated with poorer recurrence-free and progression-free survival rates. Moreover, PAX5 expression was found to be an independent prognostic factor for recurrence-free survival by a multivariate analysis.

[Molecular nature of renal tumours of adults]

Significant progress has been achieved recently in the cytogenetic and molecular research of the kidney parenchymal tumors which incidence has been steadily increasing in the developed countries. Renal cancer is an important clinical problem, still without effective therapy. The accuracy of current diagnosis, prognosis of the disease and the effectiveness of the treatment are limited by the poor understanding of its cytogenetic and molecular pathogenic mechanisms. In this review we summarize up to date cytogenetic alterations and gene expression profiles of the most important tumor genes, focusing at the classification of parenchyma tumors of adult patients.

[Expression of PAX2 and PAX8 genes in conventional type of renal carcinoma and their role in the tumor prognosis]

BACKGROUND

Sporadic renal cell carcinoma is one of the most common kidney malignancies in adults (85%). According to the IARC (The International Agency of Research on Cancer) Czech Republic has the first world position in the incidence and mortality for RCC. The prognosis of RCC is very poor because of high mortality around 70 to 50% and unpredictable progression after tumor removal. More precise molecular prognostic markers are required. Genes PAX2 and PAX8 control cell division during embryonic development and plays crucial role in tumor development because of stimulation of cell proliferation and/or inhibition of apoptotic program.

METHODS AND RESULTS

Our RCC sample collection contains 64 tumor samples and 10 "normal" renal samples extracted from the affected kidney. mRNA was isolated from all samples and converted into cDNA. Expression of PAX genes was analyzed by using relative quantification real-time PCR with TaqMan labelled probe and GAPDH gene as an endogenous control.

CONCLUSIONS

Expression of PAX2 gene was found in 97% and expression of PAX8 gene was found in 89% of analyzed tumor samples. The expression of both target genes was found in all "normal" renal samples. The level of expression of both PAX genes was very variable with the range from hundred times lower to forty times higher in comparison with the expression of chosen endogenous control. There were found no correlations between the expression of target genes and clinical-histological markers. These results do not have prognostic value yet because of short duration of patient observation. Follow-up clinical data are essential for completion of this research.

Comparison of ultrasonography, CT angiography, and digital subtraction angiography in severe carotid stenoses

Digital subtraction angiography (DSA) is considered to be the 'gold standard' for confirmation of severe (70-99%) stenoses of internal carotid arteries (ICAs). However, it is associated with a risk of complications. The aim of this study was to assess the accuracy of ultrasonography (US), computed tomographic angiography (CTA), and their combined use for the detection and quantification of severe carotid stenoses, when compared with DSA. Severe ICA stenoses were diagnosed by US in a set of 29 patients. All patients also underwent CTA and DSA. Sensitivity, specificity, positive (PPV), negative predictive values (NPV), and Pearson's correlation coefficient were used in the evaluation of the percentage of stenosis results. Homogeneity chi2 test was applied when assessing statistical significance. Severe stenosis was diagnosed in 34 ICAs. Two ICAs with uninterpretable CTA finding were excluded. The number of ICAs with stenoses 70-99%/<70%- US 32/0; CTA 29/3; US + CTA 29/3; DSA 24/8. Pearson's correlation coefficient - US 0.601; CTA 0.725; US + CTA 0.773. Sensitivity/specificity/PPV/NPV - US 1.0/0.75/0.75/xxx; CTA 1.0/0.844/0.828/1.0; US + CTA 1.0/0.844/0.828/1.0. Homogeneity chi2 test results - US, P = 0.002; CTA, P = 0.098; US + CTAG, P = 0.098. US in combination with CTA can be used for relatively secure diagnostics of severe ICA stenoses. Thus, invasive DSA can be avoided in a substantial number of patients.

Facilities for acute stroke patients care in the Czech Republic: nationwide epidemiological study

BACKGROUND AND PURPOSE

Stroke is the third most common cause of death in the Czech Republic (CR). Specialized in-patient stroke unit care improves the outcome of stroke patients. The aim of the study was to chart and improve the current facilities.

METHODS

Neurological in-patient departments exist in 75% of the districts in the CR, and in the capital Prague. Questionnaires were sent to all 79 neurological in-patient departments. A chi2 test was used for the evaluation of statistical significance.

RESULTS

There is better access to intensive/intermediary care beds (statistically not significant) and to angiography (statistically significant) in the districts with a population density of over 151 inhabitants per km2 than in districts with a lower population density (p = 0.09 and p = 0.008). Stroke patients have access within 1 hour to computed tomography of the brain in all but one, and to laboratory tests in all districts with a neurological in-patient department(s). There is no statistically significant difference in the availability of ultrasound examination of extracranial brain arteries between the sparse, and more populated districts (p = 0.715).

CONCLUSIONS

Facilities for the establishment of stroke units are quite good in the majority of highly populated areas; however, they are worse in some of the larger towns. The results of the study must be used to further improve the development of stroke care in the CR.

[Molecular genetics of Wilms' tumor]

Molecular genetics of the Wilms' tumor plays an important role in the elucidation of the genetic etiology of the tumor disease generally. Contrary to the genesis of retinoblastoma, where a single gene is inactivated by two hits, the biological signalling pathways determining the origin of the Wilms' tumor are more complex and several genes in several loci may participate. Formation of the Wilms' tumor is accompanied with the most frequent genetic alteration, which is the loss of heterozygosity on the short arm of chromosome 11. It indicates inactivation of one or several tumor suppressor genes located at 11p region. The most studied gene of the Wilms' tumor is WT1 gene, which has been cloned and sequenced. Biological function of WT1 protein is complex one and it requires probably an interaction with other proteins, DNA and also RNA. The development of the tumor determines not only the genetic changes, but also epigenetic changes, e.g., hypermethylation of promoter and genome imprinting.

Methylation changes in promoter and enhancer regions of the WT1 gene in Wilms' tumours

Although the WT1 gene has been implicated in the aetiology of Wilms' tumour, mutations in WT1 are found only in minority of the tumours. DNA methylation of regulatory elements represents another possibility of modulation of gene expression. We studied methylation in the promoter and enhancer regions of the WT1 gene in 34 Wilms' tumour patients by the polymerase chain reaction on HpaII-digested DNA and by the bisulphite method. No methylation was detected in the promoter region in either tumour or normal kidney or blood DNA samples. In contrast, a HpaII site in the enhancer region was at least partially methylated in normal kidney and blood DNA samples and in about one-third of the tumours, while the majority of tumours showed no methylation. The differential methylation in the enhancer region of the WT1 gene may indicate that methylation of this element can play a role in the regulation of this gene.

[Lower urinary tract function and its disorders]

The lower urinary tract provides two modes of operation--storage and elimination of urine. The normal function results in the coordination of contraction and relaxation of muscles of the urinary bladder and urethral sphincters. Disorders of these activities or their interaction lead to the development of lower urinary tract dysfunctions. The nervous system plays an essential role in the regulation of the functions. The control of micturition is coordinated by several regious of the central nervous system. Afferents and efferents of the peripheral nervous system carry signals from and to the lower urinary tract. The reflex circuitry controlling micturition consists of five components: spinal efferent neurons, peripheral efferent neurons, primary afferent neurons, spinal interneurons and neurons in the brain. Preganglionic neurons located in the sacral parasympathetic nucleus and lumbar sympathetic nucleus excite the peripheral efferent neurons innervating smooth muscles of the urinary bladder and urethra. Motoneurons of sacral Onuf's nucleus excite the striated muscle of the external urethral sphincter. Myelinated and unmyelinated afferent axons transmit information from the lower urinary tract to the lumbosacral spinal cord. Three receptor types of the lower urinary tract are present: tension receptors, volume receptors and "silent receptors", which become nociceptors following the sensitization. Afferent pathways terminate on spinal interneurons. Spinal interneurons relay information to the brain or to other regions of the spinal cord. Because micturition reflexes are mediated by disynaptic or polysynaptic pathways, interneuronal mechanisms are of crucial importance in the regulation of lower urinary tract. Central pathways involved in micturition reflexes are located in spinal and supraspinal areas. Micturition reflexes can be modulated at the level of the spinal cord by viscero--bladder and somato--bladder reflexes. Supraspinal areas have a more complicated organization: critical component of the micturition reflex is the pontine micturition center and the periaqueductal gray. Inhibitory and excitatory areas in the pontomedullary and hypothalamic systems and the brain play an important role in the regulation of micturition reflexes.

[DNA methylation and neoplasms]

DNA methylation and acetylation of histone proteins represent two global mechanisms controlling the gene expression. DNA methylation profiles alter during the development of the organism and during progression of neoplasia. Three types of alterations of the DNA methylation profiles were observed in the tumor cells: hypomethylation, hypermethylation and the loss of imprinting. Beside the intra-gene mutation and the heterozygosity absence, DNA methylation can be understood as the third mechanism of tumor-suppressor gene inactivation in the genesis of neoplasia. Our review article brings recent findings and hypotheses on the role of DNA methylation in the carcinogenesis and its possible application in the diagnostics and therapy of the malignant proliferation.

Use and evaluation of the Czech version of the SF-36 questionnaire self-reported health status of medical students

SF-36 questionnaires were completed by 231 medical students of the Faculty of Medicine in Hradec Králové (1997, 1998). Results of measurements of eight health dimensions are presented here. Significantly lower values for bodily pain were found in the group of overweight students. Students with some reported cured diseases have significantly lower values for bodily pain and general health dimensions in comparison with students without any reported disease. In our sample a high rate of non-smokers (86.4% men and 93.6% women) and low rate of students with BMI > 25 (18.4% men and 3.8% women) were found. About 30% of respondents reported one or more cured diseases. In addition to the SF-36 questionnaire, students in 1998 completed also a special one-page form (3). The one-page form enabled direct estimates of the eight dimensions of the health status on a scale from 0% to 100%. This study compares the results of measurement of the health status for both instruments. Differences found here are compared and discussed with similar comparisons in an American study (3). Results in both studies are similar but not the same. An indirect measurement of health status with specific questions in the SF-36 is more objective than a direct measurement with the one-page form. Nevertheless, the SF-36 is limited in the number of possible answers for some dimensions (RP, RE). In that case, our results indicate that a percentage scale from the one-page form seems better. Additionally this study compares the results of the SF-36 in Czech medical students with comparable samples from other three European countries. On average, the health dimensions of SF-36 in Czech medical students achieved the worst values in comparison with samples from Switzerland, Germany and Great Britain.

[Regeneration and transplantation of nerve tissue]

Initial experimental transplantations and attempts to induce regeneration in the nerve tissue were done during the last decades of the 19th century. Though experiments were partly successful, the Cajal's doctrine about the unchanging adult nervous system overbalanced those promising findings for long period thereafter. Only during the last thirty years requirements of clinicians moved neuroscientists to study the problems of regeneration and transplantation in the CNS again. The possibility of transferring nerve cells from a donor to the host CNS, their survival, and formation of functional contacts has been fully established. Recent findings has shown that techniques of molecular biology can overcome some of the essential problems of transplantation, e.g. the glial scar. It is evident that the key role in plastic processes accompanying integration of the transplanted cells have neurotrophic factors produced both by the host and the graft. The entire microenvironment within the transplanted tissue is altered. Some specific features of the graft may be also significant. As the implant is mostly an embryonic tissue, processes of differentiation have to be considered. Accordingly, transplantation can be used as a model in the studies of neuroontogeny. In our experiments structural association of neurones transplanted as a suspension of embryonic cells into the dorsal blade of the dentate gyrus where granule cells were eliminated was described. Differentiation and signs of synapse formation were observed. Using Timm staining method, changes in the distribution of mossy fibres were identified. In thirty-day-old grafts, high number of NADPH-d positive neurones was found. Some nitric oxide producing neurones formed long processes extending into the host tissue. Such long fibres also produced nitric oxide synthase. In order to influence the process of the graft integration we induced extreme hyperfunction by a metrazol kindling. In kindled animals, more neurones survived, however, the density of apoptotic cells was similar to control animals. Our findings may be related to the hyperfunction or to the effect of metrazol on the nerve cells of both the host and the graft. They may result from microenvironmental changes or from the activation of genes participating on the mechanism of priming.

Oncogene amplification and expression in pediatric solid tumors

Oncogene amplification and expression and their mutual relationship was analyzed in 92 pediatric tumors by Southern and Northern blot hybridization with N-MYC, ERB A, ERB B, N-RAS and Shb probes. Amplification and overexpression was associated with more advanced clinical stages of tumor, especially in neuroblastomas, rhabdomyosarcomas and ganglioneuroblastomas. The most frequent alteration observed was N-MYC amplification together with overexpression. N-RAS amplification was not detected, while the overexpression of this oncogene was found in 3 cases. Neither amplification nor overexpression was revealed in any specimen of hepatoblastoma or hepatocellular carcinoma. We suggest that oncogenes overexpression provides more accurate prognostic information than amplification.