FGF signaling is required for {beta}-catenin-mediated induction of the zebrafish organizer

We have used the maternal effect mutant ichabod, which is deficient in maternal beta-catenin signaling, to test for the epistatic relationship between beta-catenin activation, FGF signaling and bozozok, squint and chordin expression. Injection of beta-catenin RNA into ichabod embryos can completely rescue normal development. By contrast, when FGF signaling is inhibited, beta-catenin did not induce goosecoid and chordin, repress bmp4 expression or induce a dorsal axis. These results demonstrate that FGF signaling is necessary for beta-catenin induction of the zebrafish organizer. We show that FGFs function downstream of squint and bozozok to turn on chordin expression. Full rescue of ichabod by Squint is dependent on FGF signaling, and partial rescue by FGFs is completely dependent on chordin. By contrast, Bozozok can rescue the complete anteroposterior axis, but not notochord, in embryos blocked in FGF signaling. Surprisingly, accumulation of bozozok transcript in beta-catenin RNA-injected ichabod embryos is also dependent on FGF signaling, indicating a role of FGFs in maintenance of bozozok RNA. These experiments show that FGF-dependent organizer function operates through both bozozok RNA accumulation and a pathway consisting of beta-catenin-->Squint-->FGF-->Chordin, in which each component is sufficient for expression of the downstream factors of the pathway, and in which Nodal signaling is required for FGF gene expression and FGF signaling is required for Squint induction of chordin.

Thymus and myasthenia gravis: antigen processing in the human thymus and the consequences for the generation of autoreactive T cells

Peptides displayed by antigen presenting cells in the thymus shape the T cell repertoire. We investigated the antigen processing machinery of the MHC class II presentation pathway and describe the differential expression of lysosomal proteases in compartments of the thymus and the peripheral lymphoid tissue. Overexpression of certain proteases found in the thymus and thymoma associated with myasthenia gravis is likely to affect tolerance induction and may promote the generation autoreactive CD4(+) T helper cells.

Insight, symptoms and neurocognition in bipolar I patients

BACKGROUND

Level of insight and its relationship to clinical variables and neurocognitive functions was assessed in bipolar I patients.

METHODS

Verbal memory, executive functioning, sustained attention, general intelligence and other neurocognitive functions were compared between 37 chronic in- and outpatients and 31 matched normal controls. Detailed psychiatric interviews were completed to define the level of symptomatology and psychosocial functioning. Insight was assessed by the Scale to Assess Unawareness of Mental Disorder (SUMD).

RESULTS

Seventy percent of the patients were classified as having impaired insight. Prevalence of impaired insight was 47% and 94% in remitted and symptomatic patients, respectively. Symptomatic patients scored significantly below remitted patients on insight and neurocognition. Illness and symptom unawareness were related to overall level of symptoms, measures of memory, conceptual ability and right hand psychomotor speed and accuracy. Misattribution of symptoms and signs was correlated to visuomotor speed and visuospatial performance in addition to affective symptoms and thought disturbance.

CONCLUSIONS

Our findings support the hypothesis that impaired insight and other neurocognitive dysfunctions were present in a large percentage of cases among symptomatic as well as remitted bipolar patients. This may be of clinical relevance and raises important questions about the course and outcome of the illness.

Essential and opposing roles of zebrafish beta-catenins in the formation of dorsal axial structures and neurectoderm

In Xenopus, Wnt signals and their transcriptional effector beta-catenin are required for the development of dorsal axial structures. In zebrafish, previous loss-of-function studies have not identified an essential role for beta-catenin in dorsal axis formation, but the maternal-effect mutation ichabod disrupts beta-catenin accumulation in dorsal nuclei and leads to a reduction of dorsoanterior derivatives. We have identified and characterized a second zebrafish beta-catenin gene, beta-catenin-2, located on a different linkage group from the previously studied beta-catenin-1, but situated close to the ichabod mutation on LG19. Although the ichabod mutation does not functionally alter the beta-catenin-2 reading frame, the level of maternal beta-catenin-2, but not beta-catenin-1, transcript is substantially lower in ichabod, compared with wild-type, embryos. Reduction of beta-catenin-2 function in wild-type embryos by injection of morpholino antisense oligonucleotides (MOs) specific for this gene (MO2) results in the same ventralized phenotypes as seen in ichabod embryos, and administration of MO2 to ichabod embryos increases the extent of ventralization. MOs directed against beta-catenin-1 (MO1), by contrast, had no ventralizing effect on wild-type embryos. beta-catenin-2 is thus specifically required for organizer formation and this function is apparently required maternally, because the ichabod mutation causes a reduction in maternal transcription of the gene and a reduced level of beta-catenin-2 protein in the early embryo. A redundant role of beta-catenins in suppressing formation of neurectoderm is revealed when both beta-catenin genes are inhibited. Using a combination of MO1 and MO2 in wild-type embryos, or by injecting solely MO1 in ichabod embryos, we obtain expression of a wide spectrum of neural markers in apparently appropriate anteroposterior pattern. We propose that the early, dorsal-promoting function of beta-catenin-2 is essential to counteract a later, dorsal- and neurectoderm-repressing function that is shared by both beta-catenin genes.

Cyclodextrin (CD) complexes of cholesterol--their potential use in reducing dietary cholesterol intake

The main objective of this investigation was to test and see if cyclodextrins, a type of molecule which form inclusion complexes, could effectively prevent the absorption of food derived cholesterol. Cyclodextrins are nontoxic and easily tolerated, having only a slight sweet taste. alpha,beta,gamma-Cyclodextrins, 2-Hydroxypropyl-beta-cyclodextrin (2-HPCD), and heptakis-O,O-dimethyl-beta-cyclodextrin (DMCD) were tested in solutions of different concentrations. These solutions were then saturated with cholesterol and the excess cholesterol was removed. The clear solutions left were then analyzed by HPLC to assess the amount of cholesterol in the solutions, and compared to a standard. DMCD gave the best results in successfully dissolving (complexing) most of the cholesterol followed by HPCD and alpha-cyclodextrin. Beta- and gamma-CD showed nearly insignificant complex formation. After administration of 10 mg of cholesterol to mice through a gastric tube, the cholesterol level increased about 125-130%, and only 15-20%, if the cholesterol was administered together with 20 mg of DMCD. That means, the DMCD formed complexes with approximately 80-85% of the cholesterol administered in the mice gastrointestinal tract.

Mutation scanning of the p53 tumor suppressor gene in renal and liver transplant patients in Hungary

INTRODUCTION

The increased incidence of malignancies among transplanted patients is well known. Abnormal function of the p53 tumor suppressor gene has been reported in more than half of all tumors. The aim of our study was to detect point mutations of p53 gene in transplanted patients because the presence of mutations may be a predictive factor for tumor development. An earlier diagnosis can help to develop new strategies for immunosuppressive therapies.

METHODS

Three point mutations were chosen based on the literature: exon5-codon175, exon7-codon248, exon8-codon273. Genomic DNA from the plasma of 60 liver, 362 renal transplants, and 45 nontransplanted patients with different tumors and 20 suspected healthy patients were analyzed with a real-time PCR method using the Roche LightCycler. The mutations were evaluated by melting curve analysis.

RESULTS

We elaborated a special protocol for scanning the above mentioned p53 point mutations, which were proved by sequencing as well. Among 487 patients, 486 showed a wild-type genotype. The only patient carrying a mutation at codon 273 (heterozygous) was a liver transplant patient, who developed pancreas carcinoma and had already died.

CONCLUSION

Our data suggest that mutations of the targeted codons in leukocyte DNA seem to be rare, but a mutation could be lethal. The evaluated three point mutations of p53 gene were not predictive for tumor development.

Decreased frequency of intrathymic regulatory T cells in patients with myasthenia-associated thymoma

Naturally occurring CD4+CD25+ regulatory T cells (Treg) are essential for the control of unwanted autoimmune responses. In this study, we analysed their frequency in peripheral blood and in the thymus/thymomas of patients with myasthenia gravis (MG). We found a marked decrease in the number of CD4+CD25+ thymocytes in MG-associated thymomas, but no differences in the peripheral compartment, suggesting that the thymic development of Treg might be impaired in these patients.

Comparing cytomegalovirus prophylaxis in renal transplantation: single center experience

BACKGROUND

Cytomegalovirus (CMV) presents a serious threat to CMV-seronegative recipients (R-), who have received an organ from a seropositive donor (D+).

OBJECTIVES

We compared the effectiveness of three different prophylactic protocols in CMV D+/R- patients and reviewed data on patients who received no prophylaxis.

PATIENTS AND METHODS

We reviewed 1137 kidney transplantations from 1995 to 2004. Of these, 147 recipients were CMV negative (D+/R-); 125 patients received CMV prophylaxis. Group I received CMV hyperimmune gammaglobulin only, group II received CMV hyperimmune gammaglobulin plus oral ganciclovir, and group III received prophylaxis with oral ganciclovir only.

RESULTS

In group I, CMV infection was observed in 31 of 53 patients (59%), and CMV disease was diagnosed in 9 (17%) during the prophylaxis. In the first year post transplant, a total of 41 of 53 patients (77.5%) had primary CMV infection. In group II, CMV infection occurred in 7 of 30 patients (23%), and CMV disease was diagnosed in only 2 (7%) during prophylaxis. In the first year post transplant, a total of 9 of 30 patients (30%) had primary CMV infection. In group III, 9 of 42 patients (21%) developed CMV infection during prophylaxis, and CMV disease was not observed. In the first year post transplant, a total of 13 of 42 patients (30%) had primary CMV infection. In contrast, all 22 CMV D+/R- patients without prophylaxis developed CMV infection (100%); CMV disease was diagnosed in 10 (45%), and 1 patient died.

CONCLUSIONS

Prophylaxis with hyperimmune gammaglobulin and/or oral ganciclovir significantly reduces CMV infection and disease. Prophylaxis with ganciclovir was significantly more effective than hyperimmune gammaglobulin monoprophylaxis, and more cost effective than combined prophylaxis.

Functional neuroanatomy of human vocalization: an H215O PET study

Vocalization in lower animals is associated with a well-described visceromotor call system centered on the mesencephalic periacqueductal grey matter (PAG), which is itself regulated by paramedian cortical structures. To determine the role this phylogenetically older system plays in human phonation, we contrasted voiced and unvoiced speech using positron emission tomography and then evaluated functional connectivity of regions that significantly differentiated these conditions. Vocalization was associated with increased and highly correlated activity within the midline structures--PAG and paramedian cortices--described in lower mammalian species. Concurrent activation and connectivity of neocortical and subcortical motor regions--medial and lateral premotor structures and elements of basal ganglia thalamocortical circuitry--suggest a mechanism by which this system may have come under an increasing degree of voluntary control in humans. Additionally, areas in the temporal lobe and cerebellum were selectively activated during voiced but not unvoiced speech. These regions are functionally coupled to both visceromotor and neocortical motor areas during production of voiced speech, suggesting they may play a central role in self-monitoring and feedback regulation of human phonation.

Aberrant tetranectin expression in human breast carcinomas as a predictor of survival

AIMS

Tetranectin (TN), a plasminogen kringle 4 binding protein, is thought to play a prominent role in the regulation of proteolytic processes via binding to plasminogen. The aim of this study was to evaluate the expression of TN in human breast cancer and adjacent normal breast tissue and to determine the impact of this expression on survival.

METHODS

A retrospective analysis was performed on 189 patients with breast cancer, with a median follow up time of 10.6 years. The expression of TN was assessed in tumour tissue and adjacent normal breast tissue by immunohistochemistry, and the prognostic relevance of its expression in tumour cells was evaluated.

RESULTS

TN was highly expressed in connective tissue fibres surrounding normal breast epithelium, but not in normal epithelial cells. High expression of TN in tumour cells was found in 131 (69%) of the tumour samples. By western blot analysis, no significant difference in the amount and molecular weight of TN was seen between tumour tissue and normal tissue. Strong TN immunoreactivity in tumour tissue was predictive of poor disease free and tumour specific overall survival. By multivariate analysis, high TN expression in cancer cells was an independent prognostic factor for disease free and tumour specific overall survival.

CONCLUSIONS

Our results demonstrate differential TN expression in normal and malignant breast tissue and a prognostic impact of TN protein expression in breast carcinoma tissue. These data suggest a possible role of TN in invasiveness and the metastatic spread of human breast cancer.

[Visual evoked potentials and ultrasonography in ischemic optic neuropathy]

THE AIM OF THE PAPER

To emphasize the importance of the examination VEP and Doppler ultrasonography for ION diagnostic establishment and their monitoring.

MATERIALS AND METHODS

There have been taken into VEP examination 43 patients, simple stimuli (flash) having used. For Doppler ultrasonography there have been taken into examination 38 patients whose extracerebral carotidian arterial system and ophthalmic artery have been examined.

RESULTS AND DEBATES

The VEP examination at the beginning of NOI have emphasized a depress of the amplitude of the VEP with normal VEP latency in 65.1% of cases and a depress of the amplitude with prolonged latency time in 4.7% of cases. VEP examination after 7-14 days from the ION beginning have emphasized only the depress of the amplitude in 48.8% of cases. Doppler ultrasonography examination have emphasized diffuse atherosclerotic lesions in 81.6% of cases and local carotidian stenosis in 7.9% of cases.

CONCLUSIONS

VEP and Doppler ultrasonography examinations complete in an efficient way the range of clinical examinations and permit the getting of useful results in ION diagnosis. The examinations are complementary allowing the estimation of the nervous conductibility degree of deterioration and of the vascular pathway of the illness. VEP and Doppler ultrasonography are easy reproducible and non-aggressive methods which bring important diagnosis elements and allow ION monitoring.

[Clinical aspects in ischemic optic neuropathy]

THE PURPOSE OF THE PAPER

Clinical evaluation of the patients suffering of Ischaemic Optic Neuropathy (ION) for the establishment of a quick and accurate diagnosis and a therapeutical strategy.

MATERIAL AND METHOD

There have been taken into study 56 patients whose epidemiological, aetiological aspects and clinical manifestations were followed up from the beginning and during the evolution.

RESULTS AND DEBATES

In ION aetiology there have been found: atherosclerosis + systemic hypertension (87.4%); giant cell arteritis (7.2%); normal-tension glaucoma (3.6%) and systemic hypotension (1.8%). Diabetes mellitus and dislipidemia have been found in 21.4% of cases. In most of the cases the visual acuity was quickly reduced affecting only one eye, in two of the cases it was bilaterally affected.

CONCLUSIONS

ION affects old people, without any differences between sexes, whose predominant aetiology is atherosclerosis associated with hypertension. ION are serious illnesses, the visual deficit persists or get worse even if an appropriate treatment is made. The establishment of the aetiology, arteritical or atherosclerotical, has a great clinical importance for the therapeutics strategy.

[Viral screening of organ donors and human cytomegalovirus seroprevalence in the Hungarian population]

The authors investigated 998 organ-donors for Human cytomegalovirus seroprevalence. The donors were divided into three age-groups. In organ-donors the seroprevalence was found to be 84%. A study was also conducted on a fourth group consisting of 200 residents from an old-age home. The youngest donor was 2 years of age, the eldest old-age home resident was of 92 years. The examined persons represent the hungarian population. It was found that as the result of the investigation of all 1198 subjects, the Human cytomegalovirus overall seroprevalence in Hungary is 86%. The age specific prevalence increases starting from 73% in the first group (2 to 20 years old) to 99% in the fourth group (71 to 92 years old). This has indicated that most of the population acquired the primary infection in the childhood or during early adulthood. According to these results the authors resumed that in Hungary the Human cytomegalovirus seroprevalence is high. This would cause problems when a seronegative organ-recipient needs an organ transplantation. Between males and females a significant difference of Human cytomegalovirus seroprevalence was found: 89% of females were seropositive in contrast to 81% of males (p < 0.05). The organ-donors were also examined for the presence of HBsAg, anti-HCV and anti-HIV. 1.8% of donors were HbsAg positive, 0.9% were anti-HCV positive and 1 person was anti-HIV positive, but these results weren't verificated.

Skin manifestations in parasite infection

BACKGROUND

Intestinal parasites stimulate IgE synthesis by their proteinases. Because of their ability to induce IgE production and mast cell degranulation (either directly, e.g. Ascaris, or via specific IgE) it is possible that some parasites induce allergic manifestations. Some parasites may be more allergenic than others due to their allergenicity. Genetic predisposition, nutritional status, and psychosocial variables of the host and the time and degree of allergen exposure may also play an important role.

THE AIM

Of our study was to investigate which parasites are more frequently related to the skin manifestations and if atopic background of the host has a role in these skin allergic hives in intestinal parasites.

MATERIAL AND METHOD

55 patients (13 men, mean age 36 years old) infested with digestive parasites were skin prick tested to inhalant allergens (house dust mites, pollens, animal dander) in order to evaluate the atopic status. All patients had allergic skin manifestations (rash and hives) and angioedema due to their intestinal parasites, which remitted after antiparasitic treatment.

RESULTS

Forty (73.3%) patients presented angioedema and 15 patients (26.6%) had chronic rash. Patients who were infected with Ascaris had more severe symptoms: more than 2/3 had angioedema, and only one third had chronic rash. More than 2/3 of the patients were infested with Ascaris lumbricoides: 38 patients (69.09%), and only one third were infested with Giardia lamblia: 18 patients (32.72%). Only one third of the patients (17-30.9%) had positive skin prick tests for at least one inhalant allergen.

CONCLUSIONS

The parasite most frequently implicated in skin allergic manifestations in our region is Ascaris lumbricoides. Acute angioedema or chronic rash are the major skin manifestations in parasitic infestation. The atopic trait has no importance in the appearance of allergic manifestations in parasitic infestation.

The neural organization of discourse: an H2 15O-PET study of narrative production in English and American sign language

In order to identify brain regions that play an essential role in the production of discourse, H2 15O-PET scans were acquired during spontaneous generation of autobiographical narratives in English and in American Sign Language in hearing subjects who were native users of both. We compared languages that differ maximally in their mode of expression yet share the same core linguistic properties in order to differentiate the stages of discourse production: differences between the languages should reflect later, modality-dependent stages of phonological encoding and articulation; congruencies are more likely to reveal the anatomy of earlier modality-independent stages of conceptualization and lexical access. Common activations were detected in a widespread array of regions; left hemisphere language areas classically related to speech were also robustly activated during sign production, but the common neural architecture extended beyond the classical language areas and included extrasylvian regions in both right and left hemispheres. Furthermore, posterior perisylvian and basal temporal regions appear to play an integral role in spontaneous self-generated formulation and production of language, even in the absence of exteroceptive stimuli. Results additionally indicate that anterior and posterior areas may play distinct roles in early and late stages of language production, and suggest a novel model for lateralization of cerebral activity during the generation of discourse: progression from the early stages of lexical access to later stages of articulatory-motor encoding may constitute a progression from bilateral to left-lateralized activation. This pattern is not predicted by the standard Wernicke-Geschwind model, and may become apparent when language is produced in an ecologically valid context.

[Poliomyelitis and the post-polio syndrome]

In developed countries as well as in Hungary polio virus related disease disappeared completely due to the extensive administering of vaccine. As a result, young and middle-aged doctors have no experience of encountering acute polio virus infection but instead they meet its resultant impairments and disabilities. Persons who had suffered the onset of poliomyelitis 3 or 4 decades earlier, may to develop a new set of symptoms and functional declines. The criteria for post-polio syndrome were identified and its impairments and disabilities were described. It is only within the last decade that the adaptive changes in muscular tissue, insufficiently compensed denervation, together with the effects of physiotherapy, have become better known. The aim of this paper is to review the present situation concerning the struggle for keeping the polio virus in check, to give a short summary of the post-polio syndrome and to draw attention to the importance of rehabilitation.

[Qualitative and quantitative detection of hepatitis C virus RNA by PCR technique. Monitoring of viral copies after liver transplantation]

The authors demonstrate the HCV nucleic acid amplification method is not wide-spread in Hungary yet. The HCV-RNA is usually detectable 2-4 weeks after infection independently the immunostate of the patients. The authors help to select the adequate measurement(s) in logical order when HCV infection is suspected. The benefit of the PCR method is emphasized. Monitoring of the HCV-RNA titer of the liver transplanted patients promotes to establish the fluctuation of HCV-RNA copies and the effectivity of therapy following transplantation. The detection of HCV-RNA by PCR method is a proof of an acute or chronic infection and rules out past infection. The quantitative PCR measurement is useful for determination of indication and control of efficacy of antiviral therapy.

PET evaluation of bilingual language compensation following early childhood brain damage

We report a positron emission tomography (PET) study in a 37-year-old, right handed, bilingual (English and American Sign Language) male with left frontal lobe damage, without evidence of language or general intellectual dysfunction. A brain MRI scan demonstrated an atrophic lesion of the left dorsolateral prefrontal, orbital, and opercular cortices extending from the frontal pole to precentral gyrus and including parts of anterior cingulate cortex, due to an probable infantile encephalitis. H(2) (15)O PET scans found evidence of increased right hemisphere activity compared to normal controls during spontaneous generation of narrative in both English and ASL. Neuropsychological data were within normal limits with the exception of visuospatial function. The results suggest the possibility that plasticity, unmasking of neural pathways, and or other adaptations of language function in the right hemisphere may have occurred, and are discussed with regard to the crowding hypothesis.

[A glimpse into a new discipline: medicinal inorganic chemistry]

Authors discuss some aspects of the medicinal application of metal complexes. They deal with anti-effective agents, bismuth anticulcer and gold antiarthritic drugs, and with agents that influence the NO balance in the cardiovascular system. Further, they concern with insulin mimetic vanadium compounds, metal complexes of superoxide dismutase activity, photodynamic therapy, and the treatment of copper deficiency.

Prediction of early renal graft function by the measurement of donor urinary glutathione S-transferases

BACKGROUND

We have investigated the possibility of urinary alpha- and pi class glutathione S-transferases (GST-a; GST-pi) serving as a valuable parameter to predict early graft function after transplantation.

METHOD

Urinary GST concentrations of 61 donors (DON) and recipients (REC) were analyzed at preoperative, intraoperative, and postoperative periods. We grouped recipients according to the early postoperative graft recovery days.

RESULTS

The donor graft function, represented by the donor urinary GST concentration (GST-pi:17,1+/-12 microg/l mmol creatinine (crea); GST-a:14,3+/-10 microg/mmol crea), sustained a loss in comparison to the healthy controls (GST-a; pi< or =1 microg/mmol crea). According to statistical analysis, the donor GST-pi level showed a strong correlation with graft recovery days-pi (r = 0.84; P<0.001). The early graft function cannot be predicted by means of cold ischemia time (22.8+/-3.4 hr), nor handling time (42.4+/-11.1 min), nor even the intraoperative enzyme concentrations. The GST-pi cut off level (12.55 microg/mmol crea) might predict the possible posttransplant graft dysfunction. The discriminative analysis showed that using only DON GST-pi alone could discriminate well between the groups among all grafts in 68%.

CONCLUSION

Prognosis is poorer if the donor GST-pi concentration is above 12.55 microg/mmol crea. On the basis of the determination of GST-pi concentration in the donor urine, we can predict graft viability before the surgical procedure with a reliability of 68%.

[Diagnostic value of glutathione-S-transferase]

The authors evaluated the diagnostic value of the glutathione-S-transferase (GST) enzyme in the medical practice. The GST is widely distributed in human tissues, the majority of the enzyme protein is present in the cytoplasm. GST plays a pivotal protective role against the environmental damages. It can be made a conclusion from the quantity, the localization of the enzyme expression and enzyme forms to the degree of chemical insult suffered by the organism. The increase of alpha GST izoenzyme can reflect the degree of the hepatocellular and renal proximal tubular epithelium damage. The overexpression of pi-class GST represents the injury of bile epithelium and renal distal tubules. Overexpression of GST is associated with tumor appearances and with resistance to cytostatic agents. It was possible to took the enzyme izoenzymes apart, to identify them--hereby to explore their origin--and to detect their quantity with the development of the separation techniques, the immunological and genetical methods. Since the enzyme expression is in direct proportion to the magnitude organs and tissues damage or/and the presence of specific izoenzymes suspects tumor formation, for this reason the monitoring of the GST expression could give a help for the physicians in creating the diagnosis.

[Clinical evaluation of factors VIII and IX manufactured in Hungary, based on results of the first half year]

The development of anti-factor VIII/IX antibodies (inhibitor-induction) and the transmission of viral infections are the most significant complications of haemophilia treatment. The Humafactor-8 and Humafactor-9 are high-purity pasteurized factor VIII and IX concentrates, which are produced from pooled plasma of Hungarian donors by ion-exchange chromatography. The clinical study has been accomplished in two steps: first we have demonstrated the biological efficacy of the concentrates in a phase IV trial. After that we followed 13 patients with severe haemophilia for 6 months in respect of virus-safety and inhibitor-induction. According to our results the recently developed domestic FVIII/FIX concentrates display appropriate biological activities and they are safe as blood-borne virus-transmission and immunogenicity are concerned.

Sensitive method for the determination of KC 12291 in rat plasma and urine by high-performance liquid chromatography

A sensitive and selective ion-pair reversed-phase HPLC method has been developed for the quantitative determination of KC 12291 and its major metabolite, KC 13194, in rat plasma and urine. An Ultrasphere ODS column constructed by using a mobile phase of 1 mM 1-octanesulfonic acid containing acetonitrile-0.1 M triethylamine phosphate buffer, pH 2.2 (29:71, v/v in plasma and 27:73, v/v in urine), an internal standard and a fluorescent detector (excitation 265 nm, emission 370 nm) were used for the separation and the quantitative determination, respectively. The plasma samples were made alkaline and both compounds were cleaned up by the use of liquid-liquid extraction. The limit of quantification was 10 ng/ml for KC 12291 in plasma and urine and for KC 13194 and 100 ng/ml in plasma, respectively. The assay has been validated with respect to system suitability, accuracy, precision, recovery, stability and ruggedness. All validated parameters were found to be within the necessary limits.