Mini review on blood-brain barrier penetration of pyridinium aldoximes.

This paper reviews the blood-brain barrier (BBB) penetration of newly developed pyridinium aldoximes. Pyridinium aldoximes are highly charged hydrophilic compounds used in the treatment of subjects exposed to organophosphonates because they are effective as acetylcholinesterase reactivators. Pyridinium aldoximes have antidotal effects against poisoning with cholinesterase inhibitors, a frequent problem affecting people working with organophosphate-based insecticides and pesticides. Toxic organophosphonate products such as sarin and tabun can be used by terrorists as chemical warfare agents. This poses a severe challenge to all innocent and peace-loving people worldwide. This review gives a brief summary of BBB transporters and description of the current in vitro and in vivo methods for the characterization of BBB penetration of established and novel pyridinium aldoximes. The authors provide a putative mechanism of penetration, outline some future ways of formulation and discuss the possible advantages and disadvantages of increasing BBB penetration.

Cytometry-acquired calcium-flux data analysis in activated lymphocytes.

Flow cytometry enables the sequential determination of calcium levels in millions of stimulated lymphocytes over a short period of time. Current algorithms available are not suitable for the statistical analysis of this large amount of data. The authors aimed to develop a robust algorithm that fits a function to median values of measured data and provides an opportunity for statistical comparison between different calcium-flux measurements. The alteration of calcium signal was monitored in CD4+ cells loaded with calcium binding fluorescent dyes and stimulated with phytohemagglutinin; the alteration of calcium signal was monitored for 10 minutes. The authors also reanalyzed published calcium-flux data of CD3+ cells and Jurkat cells stimulated with different concentrations of anti-CD3 and thapsigargin. The authors fitted different functions to the medians of data per time unit and identified hormesis function as the best fitting one. On the basis of the optimally fitting function, the authors calculated the most relevant biological descriptors such as starting value, peak, time to reach the maximum, and time to reach 50% of maximum before and after the peak. Statistically significant differences in cell activation kinetics at different stimulatory concentrations were also demonstrated. This approach enables us to characterize the kinetics and distribution of calcium-flux data derived by flow cytometry and may be a reliable tool for the characterization of lymphocyte activation (for details see: http://calciumflux.intralab.eu).

Survivin promoter polymorphism and cervical carcinogenesis.

BACKGROUND: Survivin, a novel member of the inhibitor of apoptosis family, plays an important role in cell cycle regulation. A common polymorphism at the survivin gene promoter (G/C at position 31) was shown to be correlated with survivin gene expression in cancer cell lines. AIM: To investigate whether this polymorphism could be involved in the development of human papillomavirus (HPV)-associated cervical carcinoma. METHODS: Survivin promoter polymorphism was detected in patients with cervical cancer, in patients with equivocal cytological atypia and in a control population using polymerase chain reaction (PCR-restriction fragment length polymorphism (RFLP) and PCR-single strand conformation polymorphism analysis. HPV was typed in patients with cervical cancer and cytological atypia using PCR-RFLP. RESULTS: No statistically significant differences were found in the genotype distributions of the survivin promoter variants among our study groups. CONCLUSIONS: The survivin promoter polymorphism at position 31 may not represent an increased risk for the development of cervical cancer, at least in the population studied here.

Transcriptional activity of human papillomavirus type 16 variants having deletions in the long control region.

Transcription of the E6 and E7 viral oncogenes of human papillomavirus (HPV) type 16 is regulated by the P97 major early promoter, and enhancer and silencer elements found in the long control region (LCR). In this study, we tested the transcriptional activity of natural HPV 16 variants having long deletions in the LCR. The HPV 16 LCR regions were amplified from invasive cervical cancer specimens, and cloned into the reporter vector pALuc. Transcriptional activity of the different clones was measured by luciferase test after transient transfection into HeLa cells. The deletions found in the LCR encompassed parts of the enhancer and either the YY1-specific silencer alone or together with the CDP-specific silencer. The transcriptional activity of these deletion variants were usually reduced compared with that of the corresponding full-length clones. However, a deletion variant lacking the whole enhancer and both silencer regions retained substantial enhancer activity on the P97 promoter. These results point to the existence of a novel context-dependent enhancer element in the 5' LCR of HPV 16.

Infra-His blocked premature atrial contractions simulating 2:1 sinoatrial block in a patient with an atrio-His bypass tract.

Blocked atrial premature contractions simulated 2:1 sinoatrial block because those were superimposed on the T wave of the preceding sinus beats and were not visible on the surface electrocardiogram of our patient. Additionally, His bundle recordings and premature atrial stimulation demonstrated the presence of an atrio-His anomalous pathway. The premature atrial contractions traveled anterograde via the anomalous pathway and were blocked distally to the His bundle. The term, pseudosinoatrial block, is used to describe the arrhythmia because there was no evidence of an intrinsic abnormality of sinus node function and sinoatrial conduction.

HHV-8 ELISA based on a one-step affinity capture of biotinylated K8.1 antigen.

The immunogenic envelope antigen gp35-37 of human herpesvirus-8 (HHV-8) is encoded by orfK8.1. An ELISA is described using streptavidin capture of bacterially expressed and biotinylated recombinant K8.1 antigen. The antigen capture strategy provides a simple and reliable method, which does not require high yield production and purification of the recombinant antigen before the serological assay. The specificity and sensitivity of the K8.1 ELISA were validated by gp35-37 envelope antigen Western blot and anti-lytic membrane immunofluorescence assay using lytically induced HHV-8 infected BCBL-1 cells. Under the established ELISA conditions, eight of the 10 Kaposi's sarcoma patients and five of the 180 healthy blood donors had IgG antibodies to K8.1 envelope antigen.

Frequency of p53 codon 72 genotypes in human papillomavirus associated squamous intraepithelial lesions and cervical cancer.

BACKGROUND: A recent study suggested that the p53Arg (at residue 72) homozygous genotype could be a potential genetic risk factor for cervical cancer among white women. To confirm this result we examined the proportion of p53 genotypes in a larger number of patients with cervical cancer and in patients with squamous intraepithelial lesions (SIL) compared to a control population. MATERIALS AND METHODS: We used allele-specific primers to amplify the p53Arg and p53Pro sequences and we examined the proportion of genotypes in the study populations using chi 2-test. RESULTS: The distributions of p53Arg homozygous, heterozygous and p53Pro homozygous genotypes were 63%, 27% and 10% in cervical cancer patients, 53%, 36% and 8% in individuals with SIL, and 60%, 36% and 4% in control population. Using chi-square test, no significant difference was found between genotype frequencies in the study groups. CONCLUSION: Thus, the p53Arg homozygous genotype does not seem to increase the risk of cervical cancer in Hungarian women.

Integration status of virus DNA and p53 codon 72 polymorphism in human papillomavirus type 16 positive cervical cancers.

BACKGROUND: The aim of this study was to determine the physical state of HPV16 DNA and to reveal any association between the physical state of virus DNA and pathologic or prognostic factors in HPV16 positive cervical cancers. The other aim was to estimate the role of p53 codon 72 polymorphism in disease progression. MATERIALS AND METHODS: The presence and physical state of HPV16 DNA was analysed by Southern blot hybridisation and E1-E2 specific PCRs in the primary tumours and pelvic lymph nodes of 85 cervical carcinoma patients. Results Integrated HPV16 DNA was found in 32 out of 41 (78%) primary tumours and 2 out of 22 (95%) lymph nodes carrying HPV16 DNA. No significant association was found between integration of virus DNA and course of the disease. There was a trend towards an association between disease recurrence and the presence of the p53 codon 72 arginine homozygous genotype (OR = 3.41, p = 0.23). CONCLUSION: The physical state of HPV16 DNA does not seem to play a major role as a prognostic indicator in Hungarian cervical cancer patients, while the p53 codon 72 genotype may have an impact on the clinical outcome of the disease.

Hypoglycemia activates compensatory mechanism of glucose metabolism of brain.

The effect of plasma glucose concentration on the cerebral uptake of [18F]-fluorodeoxy-D-glucose (FDG) was studied in a broad concentration range in a rabbit brain model using dynamic FDG PET measurements. Hypoglycemic and hyperglycemic conditions were maintained by manipulating plasma glucose applying i.v. glucose or insulin load. FDG utilization (K) and cerebral glucose metabolic rate (CGMR) were evaluated in a plasma glucose concentration range between 0.5 mM and 26 mM from the kinetic constant k1, k2, k3 obtained by the Sokoloff model of FDG accumulation. A decreasing set of standard FDG uptake values found with increasing blood glucose concentration was explained by competition between the plasma glucose and the radiopharmacon FDG. A similar trend was observed for the forward kinetic constants k1, and k3 in the entire concentration range studied. The same decreasing tendency of k2 was of a smaller magnitude and was reverted at the lowest glucose concentrations where a pronounced decrease of this backward transport rate constant was detected. Our kinetic data indicate a modulation of the kinetics of carbohydrate metabolism by the blood glucose concentration and report on a special mechanism compensating for the low glucose supply under conditions of extremely low blood glucose level.

[Blocked atrial extrasystole simulating impaired anterograde conduction during atrial stimulation]. / Alacsony Wenckebach-pontot szimuláló bigemin elrendezödésü blockolt pitvari extrasystolia.

In a 72-years-old patient with intermittent bradycardia definitive atrial pacing was considered. Surface ECG was misleading because of demonstrating 2:1 anterograde block during atrial stimulation at a rate of 100 beats per minute. Intracardiac recordings disclosed the bigeminal occurrence of premature atrial contractions. Every second stimuli fall within the premature atrial contraction's refractory period simulating impaired AV-conduction. Our report emphasizes the importance of intracardiac recordings during atrial stimulation in order to evaluate the anterograde conduction before pacemaker implantation.

[AV reciprocating tachycardia with intermittent bundle branch block in latent Wolff-Parkinson-White syndrome]. / Intermittáló szárblokkal járó A-V reciprok tachycardia rejtett Wolff-Parkinson-White-syndromában.

This report deals with a patient with concealed Wolff-Parkinson-White syndrome in whom both narrow and wide QRS tachycardias were observed. The simultaneous occurrence of various QRS morphology during supraventricular tachycardia results in a challenging diagnostic ECG problem. The cycle length during tachycardia with left bundle branch block was longer than the cycle length during narrow QRS supraventricular tachycardia and with functional right bundle-branch block. Electrophysiologic studies revealed fixed V-A conduction time and increased V-A conduction during tachycardia with left bundle branch block. These studies suggested the presence of a concealed left-sided anomalous pathway. Differentiation between intra- and extranodal re-entry and therapeutic modalities are also discussed.

[Follow-up of high risk, human papillomavirus (HPV)-positive patients with cancer of the uterine cervix]. / Magas kockázatú humán papillomavírus (HPV)-pozitív, méhnyakrákos betegek kórlefolyásának követése.

The study population consisted of 30 cervical cancer patients stage I.a-II.b. (FIGO) stages operated on according to the Wertheim technique. A parallel histological evaluation and HPV status determination were carried out on biopsies from the primary tumors and on the regional lymph nodes. A general primer mediated polymerase chain reaction (PCR) was performed at first and the samples not amplified were examined by type-specific primers. All except one primary tumors contained DNA-sequences characteristic for high risk HPV-types. The lymph nodes of these HPV-positive patients proved to be also HPV-positive with a frequency of 25/30 (83%). The frequency of the HPV-positivity was higher (100%) in the group of patients with HPV-18 positive status, than in the HPV-16 positive group. Two thirds of the evaluated regional lymph nodes were HPV-positive in the HPV-16 group of patients. The same HPV-types were harboured by the primary tumors and by the regional lymph nodes both in the HPV-16 positive and HPV-18 positive groups of patients. In the HPV-16-positive group of patients metastatic lymph nodes occurred with a frequency of 3/16, while the frequency of HPV-16 positivity in the same nodes was 11/15. In the group of patients with HPV-18 positivity the difference was even greater, 1/12 v. 12/12. Early recurrences were detected in a relation of 3 to 1 in the group of patients with histologically tumor-free and metastatic-positive lymph node status. At the same time all of the lymph nodes in this group with early recurrency (4/4) contained DNA-sequences characteristic for the HPV-18 type. These findings raise the hypothesis that the HPV-specific nucleic acids detected in the lymph nodes can be taken as sensitive indicators of metastases. The follow-up results support these hypothesis as patients with HPV-18 positive lymph node status showed early recurrencies and short survival that is poor prognosis not corresponding to the early stage of cervical cancer with histologically negative lymph node status.

[Myocarditis simulating myocardial infarction]. / Szívinfarktust utánzó myocarditis.

Acute myocarditis caused by infectious mononucleosis simulated myocardial infarction, initially the quantitative and qualitative blood picture was normal. Repeated blood and serological studies confirmed the diagnosis, which was altered by acute porphyria caused by infection. In each case of young patients with myocardial infarction and in older patient with coexisting infectious symptoms, myocarditis must be considered. Since the cardiac manifestation may precede the infectious disease symptoms, repeating the necessary examinations may be mandatory.

Dendrodendritic connections between the cochlear efferent neurons in guinea pig.

The outer hair cells of organ of Corti are innervated by the efferent neurons of medial olivocochlear neurons (MOC) of the brainstem which modify the cochlear auditory processing and sensitivity. Most of the MOC neurons are excited by a dominant ear and only a small portion of them is excited by both ears resulting in a binaural facilitation. The functional role of the feedback system between the organ of Corti and the cochlear efferent neurons is the protection of the ear from acoustic injury. The rapid impulse propagation in the bilateral olivocochlear system is suggestive of an electrotonic interaction between the bilateral olivocochlear neurons. The morphological background of the MOC pathway is not yet completely characterized. Therefore, we have labeled the bilateral cochlear nerves with different neuronal tracers in guinea pigs. In the anesthetized animals the cochlear nerves were exposed in the basal part of the modiolus and labeled simultaneously with different retrograde fluorescent tracers. By using confocal laser scanning microscope we could detect close appositions between the dendrites of the neurons of bilateral MOC. The distance between the neighboring profiles suggested close membrane appositions without interposing glial elements. These connections might serve as one of the underlying mechanisms of the binaural facilitation mediated by the olivocochlear system.

Medicinal chemistry of drugs used in diabetic cardiomyopathy.

Diabetes mellitus is a common disease and contributes to a high degree of morbidity and mortality. Cardiovascular complications, including diabetic cardiomyopathy are major causes of morbidity and mortality in diabetic patients. Diabetic cardiomyopathy is a condition that affects the myocardium, primarily. It is not necessarily associated with ischemic heart disease, high blood pressure, valvular or congenital anomalies. The pathology of diabetic cardiomyopathy includes interstitial fibrosis, apoptosis of cardiomyocytes, abnormal energy utilization, small vessel disease and cardiac neuropathy. These pathologies are induced by hyperglycemia and oxidative stress. Biochemical as well as electrolyte changes, especially reduced calcium availability also occurs in the myocardium of diabetic patients. The abnormal structure and biochemistry of the myocardium result in functional problems such as diastolic and systolic dysfunctions, which may cause symptoms of dyspnea and inability to tolerate exercise. No single specific therapeutic agent can treat diabetic cardiomyopathy because once the disease is overt, the management may require a variety of approaches such as risk factors and lifestyle modification, glucose control (insulin, alpha glucosidase inhibitors, sulfonylureas, biguanides, meglitinides, thiazolidinediones and dipeptidyl peptidase 4 (DPP-4) inhibitors); hormones (IGF-1); ACE inhibitors (captopril, enalapril); angiotensin II receptor antagonists (losartan, olmesartan); beta adrenoreceptor antagonists (acebutolol, carvedilol); peptides (adrenomedullin); endothelin-1 receptor antagonists (bosentan, tezosentan); calcium channel blockers (amlodipine, verapamil); antioxidants (methalothionein, alpha tocopherol, alpha lipoic acid) and antihyperlipidemic drugs (simvastatin, fenofibrate, ezetimibe) to effectively treat patients with diabetic cardiomyopathy.