Biochemical analysis of cultured chorionic villi for the prenatal diagnosis of peroxisomal disorders: biochemical thresholds and molecular sensitivity for maternal cell contamination detection

OBJECTIVES

The prenatal diagnosis of peroxisomal disorders is most often performed by biochemical analysis of cultured chorionic villus sample (CVS) or amniocytes. We aimed to (a) highlight the risk of maternal cell contamination (MCC) in biochemical prenatal diagnosis, (b) establish the threshold of these biochemical assays to MCC, and (c) document the sensitivity of PCR based genotyping of microsatellites for the detection of MCC in prenatal diagnosis of inborn errors by biochemical analysis.

METHODS

The threshold of each biochemical assay was assessed by co-cultivating fibroblasts from known affected and normal individuals. Genotypes for three polymorphic loci were determined by PCR and GeneScan analysis. The sensitivity of the molecular test was determined by DNA mixing experiments and isolation of DNA from co-cultivated fibroblasts.

RESULTS

MCC was detected in 2.5% of at risk CVS cultures (n = 79). Co-cultivation of defective and normal fibroblasts demonstrated that the peroxisomal biochemical assays were accurate at 25% contamination. Very low level DNA or cell contamination (1-5%) was detectable by genotyping, but an allele did not yield a definitive peak based on morphology until approximately 10% contamination. Furthermore, we demonstrated that other inborn errors of metabolism might be more susceptible to diagnostic error by low level MCC.

CONCLUSION

The sensitivity of the microsatellite analysis (> or =10%) is well within the threshold of peroxisomal biochemical assays. Although peroxisomal biochemical assays would not be predicted to introduce a false positive or negative result if MCC <10% were present but not recognised by molecular analysis, the same may not be true for other inborn errors of metabolism.

Microbiological spectrum and susceptibility patterns of pathogens causing bacteraemia in paediatric febrile neutropenic oncology patients: comparison between two consecutive time periods with use of different antibiotic treatment protocols

This study was devised to look at trends in the microbiological spectrum and susceptibility patterns of pathogens causing bacteraemia in paediatric febrile oncology patients. The retrospective study compared various microbiological aspects recorded for febrile oncology neutropenic patients treated with two different empirical antibiotic regimens (ceftazidime plus gentamicin during 1998-1999 and piperacillin/tazobactam plus amikacin during 2000-2002). Eighty-one bacteraemic episodes occurred in 41 patients. Overall, 132 (34 during 1998-1999 and 98 during 2000-2002) organisms were isolated: 84 (65%) Gram-negative bacteria, 39 (30%) Gram-positive bacteria and 7 (5%) fungi. Enterobacter spp. incidence decreased from 18 to 6% (P=0.07) while the recovery rates of Gram-positive organisms increased from 24 to 32% (P=0.4) during 2000-2002 compared with 1998-1999. MRSA were not isolated from any episode of bacteraemia. Five (18%) of the 28 Escherichia coli and Klebsiella spp. isolates were beta-lactamase producers (80% [4/5] isolated during 2000-2002). Twenty-seven of 28, 27/27, 23/28, 20/25 and 27/28 of these isolates were susceptible to imipenem, piperacillin/tazobactam, gentamicin, ceftazidime and ciprofloxacin, respectively. Thirty-two of 34 (94%) and 60/74 (81%) of the Gram-negative organisms isolated during 2000-2002 were susceptible to piperacillin/tazobactam and ceftazidime, respectively (P=0.076). No major differences in the microbial spectrum and antibiotic susceptibilities were recorded between the two consecutive study periods. An increase in the number of extended beta-lactamase producing E. coli and Klebsiella spp. occurred during 2000-2002. All beta-lactamase producing organisms were susceptible to piperacillin/tazobactam and initial empirical therapy with piperacillin/tazobactam was more appropriate than ceftazidime to cover most of the pathogens causing bacteraemia.

Feasibility of high-dose interleukin-2 in heavily pretreated pediatric cancer patients

BACKGROUND

The administration of high-dose interleukin-2 (IL-2) seems to be a therapeutic option for children with refractory and metastatic solid malignancies.

METHODS

We prospectively studied treatment-related toxicities, quality of life and laboratory parameters in 10 children with progressive or metastatic solid tumors (metastatic osteosarcoma, n=4; neuroblastoma stage IV, n=3; metastatic Ewing's sarcoma, n=2; metastatic Wilms' tumor, n=1) during IL-2 therapy. Patients were scheduled to receive five cycles of high-dose IL-2 by continuous infusion for 5 days every 3 weeks.

RESULTS

All patients developed fever >39 degrees C and influenza-like symptoms, with a significant decrease in Karnofsky score. In two patients treatment had to be stopped after three cycles because of severe side-effects. During IL-2 therapy a statistical significant increase in white blood cells (WBC), creatinine, gamma-glutamyltransferase, C-reactive protein, glucose and body weight was observed. In contrast, red blood cells, platelets, protein, albumin and cholinesterase significantly decreased. When results from day 1 of the first and of the fifth cycle were compared, an increase of WBC and a decrease of alkaline phosphatase was shown. No constant quantitative changes in total lymphocytes and subsets were observed during IL-2 therapy.

CONCLUSIONS

IL-2 treatment in children with refractory and relapsed solid malignancies is associated with severe, but reversible, side-effects. However, five of the 10 patients with diseases of worst prognosis could be rescued by this treatment.

The Effect of LXR Activators on AP-1 Proteins in Keratinocytes

Oxysterols, via activation of liver X receptor (LXR), regulate keratinocyte differentiation by stimulating transglutaminase cross-linking of several constituent proteins leading to the formation of the cornified envelope. We previously reported that oxysterols increase the expression of one of these cross-linked proteins, involucrin, and that this effect can be abolished by mutations of the distal activator protein (AP)-1 response element in the involucrin promoter. Furthermore, oxysterols increase AP-1 binding in an electrophoretic gel mobility shift assay and increase the expression of an AP-1 reporter. In this study, we describe the individual components of the AP-1 complex that are involved in the oxysterol-mediated AP-1 activation and stimulation of keratinocyte differentiation. We identified Fra-1 within the AP-1 DNA binding complex by supershift analysis of nuclear extracts from oxysterol-treated, cultured keratinocytes and confirmed that oxysterol treatment increased the levels of Fra-1 by western blot analysis. Additionally, on Western and Northern analysis, oxysterol treatment increased two other AP-1 proteins, Jun-D and c-Fos, whereas Fra-2, Jun-B, and c-Jun were not changed. Similar alterations in AP-1 proteins occurred when 25-OH-cholesterol or non-steroidal LXR agonists (GW3965, TO-901317) were used. These results indicate that oxysterols induce specific AP-1 proteins, thereby activating involucrin, one of the genes required for epidermal differentiation.

Increased systemic levels of norsalsolinol derivatives are induced by levodopa treatment and do not represent biological markers of Parkinson's disease

Endogenously synthesised norsalsolinol derivatives are elevated in Parkinson's disease (PD) and have been considered potentially useful biological markers of the disease. However, little is known about the impact of dopaminergic drugs on the formation of these compounds. We prospectively examined the urine concentrations of norsalsolinol, N-methyl-norsalsolinol and salsolinol in 47 PD patients and 14 control subjects. Patients and control subjects were re-examined after approximately 1 year to assess long term changes. Norsalsolinol derivatives were low in controls and untreated patients with early PD. Increased urine concentrations of norsalsolinol derivatives were significantly associated with levodopa treatment. They were elevated more markedly in the urine of patients treated with high (>600 mg daily) doses of levodopa compared with patients receiving medium (300-600 mg) or low (<300 mg) doses of the drug. There was no correlation with disease parameters such as the severity of motor disability or deficits in the cognitive performance. In the patient group, the concentrations of all three norsalsolinol derivatives declined over the period of investigation, however, they still remained elevated compared with the control group. We conclude that systemic levels of norsalsolinol derivatives in treated patients with PD are likely to derive from the metabolism of levodopa and cannot be regarded as intrinsic markers of the disease. The limited ability of norsalsolinol derivatives to pass the blood-brain barrier prevents an intracerebral accumulation of these possibly harmful compounds, which are biochemically similar to the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.

[Hallucinations in Parkinson's disease]

The appearance of psychiatric symptoms is not rare in the course and treatment of Parkinson's disease. In particular, therapy with L-dopa or dopamine agonists leads to increased dream activity. As with sleep disturbances, this can be a warning signal of paranoid hallucinatory psychosis.However, isolated visual hallucinations before manifest psychosis in Parkinson's must generally be regarded as resulting from medication. They occur in up to 30% of Parkinson's patients and often involve visual and figurative hallucinations. Visual hallucinations most probably result from the combined effect on dopaminergic and serotonergic systems in the CNS. Therapy consists in normalization of H(2)O and electrolyte levels, control of the accompanying medication, reduction of the evening doses of anti-Parkinson's medications, and serotonin antagonists such as clozapine.

GBR-12909 effect on dopamine outflow depends on phosphorylation in the caudate nucleus of the rat

Modulation of the dopamine (DA) transporter inhibitor GBR-12909 effect on DA release by protein kinases and protein phosphatases was studied in slices of the rat caudate nucleus measuring DA outflow in the superfusate of static chambers. Activation of protein kinase A and C markedly enhanced the effect of GBR-12909, whereas protein kinase inhibition by H7 reduced the GBR-12909 effect. Inhibition of protein phosphatases (PPP) 1 and 2A by okadaic acid did not modify basal outflow of DA. However, after the addition of okadaic acid a dramatic and biphasic effect was found when DA outflow was enhanced by GBR-12909. Inhibition of PPP 2A enhanced extracellular DA levels, while inhibition of PPP 1 and 2A completely abolished the effect of GBR-12909. In contrast to tetrodotoxin, the voltage-activated calcium channel blocker omega-conotoxin MVIIC inhibited GBR-12909 effects on DA outflow. Additionally, in aCSF devoid of calcium GBR-12909 did not increase DA liberation. These results suggest a complex and strong influence of phosphorylation on GBR-12909 effects on calcium channel-dependent DA outflow at low-affinity piperazine binding sites in slices of the rat caudate nucleus in vitro.

Novel methodology for the follow-up of acute lymphoblastic leukemia using FTIR microspectroscopy

In this report, we present a novel spectroscopic method of follow-up during chemotherapy treatment for B- and T-cell childhood leukemia patients. We isolated peripheral lymphocytes from blood drawn from patients before and after the chemotherapy and collected Microscopic FTIR (FTIR-MC) spectra of the isolated lymphocytes. Our results showed that nucleic acids content decreased in both types of patients. Changes in phospholipids and proteins level could be observed. The overall effects of drugs administered to the patients can be understood at the molecular level using FTIR-MC and these results are expected to stimulate wider applications of spectroscopy in leukemia research.

Clinical and laboratory manifestations of congenital dyserythropoietic anemia type I in young adults

OBJECTIVES

Congenital dyserythropoietic anemia (CDA) type I is a rare autosomal recessive macrocytic anemia whose natural history is not well documented. The aim of the present study was to evaluate the clinical picture of the disease in young adults.

METHODS

The study sample consisted of 17 patients of mean age 11.9 +/- 5.4 yr (range 18-33 yr) and one older patient (age 44 yr), all Israeli Bedouins. The degree of anemia was evaluated as well as the extent of development of gallstones and iron overload. In each subject we determined the hemochromatosis gene mutations and the uridine dyphosphate-glucoronosyltransferase (UGT-1A) gene polymorphism associated with Gilbert's syndrome.

RESULTS

The patients were found to have moderate anemia, with the women displaying lower mean hemoglobin levels than the men (8.2 +/- 0.9 g dL(-1) vs. 10 +/- 1.3 g dL(-1); P=0.0059). The majority of patients (59%) had received at least one blood transfusion, with the women having a significantly higher transfusion requirement. Although delayed puberty was noted, final height and weight were within normal limits, and eight patients had progeny. Biliary stones were found in three of 16 patients, two of whom were homozygous for UGT-1A gene polymorphism. None of the patients carried the common hemochromatosis gene mutation, although serum ferritin levels were moderately elevated (788 +/- 332 ng mL(-1)).

CONCLUSIONS

CDA type I in young adults is characterized by moderate macrocytic anemia, more severe in women, and a tendency to cholelithiasis and secondary progressive iron overload. We suggest that iron overload in this patient population should be monitored and chelation therapy initiated when indicated to prevent organ damage

Upper airway obstruction-related sleep apnea in a child with thalassemia intermedia

Obstructive sleep apnea can be caused by hypertrophy of tonsils and adenoids or neuromuscular diseases. The authors describe a child with thalassemia intermedia in whom severe obstructive sleep apnea syndrome developed. Computed tomography scanning revealed an obstruction of the nasopharynx resulting from extramedullary hematopoiesis. The child was treated with hydroxyurea and blood transfusions. Relief of symptoms was noted 1.5 months after initial treatment. Extramedullary hematopoiesis causes sleep apnea syndrome in thalassemic patients, and the treatment of hydroxyurea and blood transfusion for extramedullary hematopoiesis should be further studied.

Outcome and long-term side effects after synchronous radiochemotherapy for childhood brain stem gliomas

Between 1993 and 1999, 11 children with histologically confirmed diffuse and exophytic brain stem glioma (BSG) were treated with intensive induction chemotherapy and simultaneous external beam irradiation. Chemotherapy was performed according to the German/Austrian Pediatric Brain Tumor Study HIT '91 and included two cycles of ifosfamide (days 1-3), etoposide (days 4-6), methotrexate (days 15 and 22), cisplatin (days 29-31) and cytarabine (days 29-31), separated by a 3-week interval. Maintenance chemotherapy with carmustine, carboplatin and vincristine (8 cycles over a 1-year period) was given in those patients who responded clinically or radiographically to induction chemotherapy. Six of 11 patients showed an objective reduction in tumor size on magnetic resonance imaging and 4 of 11 are alive in good general condition >22, >22, >90 and >92 months, respectively, after diagnosis without radiographic evidence of tumor progression (1 complete remission, 2 partial remissions, 1 stable disease), but suffer from moderate to severe long-term side effects. Three patients died due to disease progression after having achieved a partial remission which lasted 5, 6 and 18 months, respectively, whereas only short-term stabilization was observed in 4 patients who died within 1 year after diagnosis. Acute hematologic toxicity was severe but manageable. This intensive combined modality treatment was toxic but yielded objective responses in more than 50% and long-term survivors in one third of childhood BSG patients.

Engineering for problem solving in future: eco-social market economy and eco-social tech

The paper differentiates approaches in technology (end-of-pipe, cleaner production, industrial ecology, zero emission and eco-social-tech) and compares them in respect to the problem solving capacity on the ecological as well as social dimension by showing the eco-impact reduction and job creation. Eco-social-tech represents the approach with highest problem solution as it is based on "eco-social market economy", which will the replace free market economy. The deep background of these innovations is "ecosophy", the wisdom of nature, which serves as guideline for eco-restructuring the world.

[Appendiceal mucocele associated with colonic neoplasm. Report of 2 cases and review of the literature]

Appendiceal mucocele is a rare entity frequently associated with colorectal cancer. We report two cases of mucocele associated with colorectal tumours. The first case (male, 64 yrs) is an appendiceal mucinous cystadenoma found incidentally during surgery for colon cancer. There is no evidence of disease after a 4-year follow-up. The second case (male, 66 yrs) is a mucocele associated with mucosal hyperplasia that was found during surgery for acute appendicitis with a periappendicular abscess. Endoscopic follow-up showed a rectal adenocarcinoma that was initially treated with local excision with T.E.M.. Examination of the pathology specimen documented vascular invasion and the patient underwent curative colorectal resection. The preoperative radiological and endoscopic diagnostic procedures and the current therapeutic approaches described in the literature are reviewed. The relevance of the association between appendiceal mucocele and colorectal cancer is emphasized. Thorough investigation of the colorectal tract is recommended after diagnosing an appendiceal mucocele.

Post renal transplantation human herpesvirus 8-associated lymphoproliferative disorder and Kaposi's sarcoma

Post-transplantation lymphoproliferative disorders (PTLDs) and Kaposi's sarcoma (KS) are immunosuppression-related tumours developing in solid organ transplant patients. Although the Epstein-Barr virus (EBV) is detected in the majority of the PTLDs during the first year after transplantation, the proportion of EBV-negative PTLDs has increased in recent years. We report a case of a 17-year-old man who developed severe immune haemolytic anaemia, KS and human herpesvirus 8 (HHV-8)-associated, polymorphic-type PTLD 9 months after allogeneic renal transplantation from his HHV-8-seropositive father. It is suggested that: (i) HHV-8 may be associated with EBV-negative, polymorphous-type PTLD occurring less than 1 year after transplantation, and (ii) PTLD may be listed among other tumours, including KS, Castleman's disease and primary effusion lymphoma (PEL), that are related to HHV-8 infection.

The peroxisome deficient PEX2 Zellweger mouse: pathologic and biochemical correlates of lipid dysfunction

Zellweger syndrome is the prototypic human peroxisomal biogenesis disorder that results in abnormal neuronal migration in the central nervous system and severe neurologic dysfunction. A murine model for this disorder was previously developed by targeted deletion of the PEX2 peroxisomal gene. By labeling neuronal precursor cells in vivo with a mitotic marker, we can demonstrate a delay in neuronal migration in the cerebral cortex of homozygous PEX2 mutant mice. Postnatal PEX2 Zellweger mice develop severe cerebellar defects with abnormal Purkinje cell development and an altered folial pattern. When the PEX2 mutation is placed on an inbred murine genetic background, there is significant embryonic lethality and widespread neuronal lipidosis throughout the brain. Biochemical analysis of PEX2 mutant mice shows the characteristic accumulation of very long chain fatty acids and deficient plasmalogens in a wide variety of tissues. Docosahexaenoic acid levels (DHA; 22:6n-3) were found to be reduced in the brain of mutant mice but were normal in visceral organs at birth. All tissues examined in postnatal mutant mice had reduced DHA. The combined use of morphologic and biochemical analyses in these mice will be essential to elucidate the pathogenesis of this complex peroxisomal disease.

The peroxin Pex6p gene is impaired in peroxisomal biogenesis disorders of complementation group 6

Human genetic peroxisomal biogenesis disorders (PBDs), such as Zellweger syndrome, comprise 13 different complementation groups (CGs). Eleven peroxin genes, termed PEXs, responsible for PBDs have been identified, whereas pathogenic genes for PBDs of 2CGs, CG-A (the same CG as CG8 in the United States and Europe) and CG6, remained unidentified. We herein provide several lines of novel evidence indicating that PEX6, the pathogenic gene for CG4, is impaired in PBD of CG6. Expression of PEX6 restored peroxisome assembly in fibroblasts from a CG6 PBD patient. This patient was a compound heterozygote for PEX6 gene alleles. Accordingly, by merging CG6 with CG4, human PBDs are now classified into 12CGs.

Prenatal diagnosis of malignant osteopetrosis in Bedouin families by linkage analysis

Autosomal recessive malignant osteopetrosis (MOP) is a lethal disease, unless bone marrow is successfully transplanted. Yet a donor may not always be available, and even when there is one transplantation results are far from optimal. The difficulty in obtaining conclusive results by sonographic and X-ray evaluation of the fetus makes prenatal molecular diagnosis highly desirable. Subsequent to the chromosomal localization of the MOP gene in Arab-Bedouin families from the Negev region in Israel, linkage analysis was used for the prenatal diagnosis of this disease in Bedouin families at risk. Twelve cases were diagnosed, three fetuses were found to be affected, and one of the pregnancies was terminated. The other two pregnancies continued to term and the diagnosis of osteopetrosis was confirmed by X-ray immediately after birth. This is the first report on prenatal diagnosis of autosomal recessive osteopetrosis by linkage analysis.

Cholesterol sulfate stimulates involucrin transcription in keratinocytes by increasing Fra-1, Fra-2, and Jun D

Lipids that are synthesized de novo in the epidermis, including fatty acids, oxysterols, 1,25-dihydroxyvitamin D(3), and farnesol, can regulate the differentiation of normal human keratinocytes (NHK). Cholesterol sulfate (CS), an epidermal lipid that is produced in the upper nucleated layers of the epidermis coincident with terminal differentiation, has been shown to play a role in the regulation of the late stages of keratinocyte differentiation, including formation of the cornified envelope. In the present study, we determined i) whether CS regulates involucrin (INV), an early keratinocyte differentiation marker, and ii) the mechanism by which CS regulates differentiation. mRNA and protein levels of INV, a precursor protein of the cornified envelope, increased 2- to 3-fold in NHK incubated in the presence of CS. In contrast, cholesterol had no effect on INV protein or mRNA levels. Transcriptional regulation was assessed in NHK transfected with INV promoter-luciferase constructs. CS increased luciferase reporter activity approximately 2- to 3-fold in NHK transfected with a 3.7-kb INV promoter construct. Deletional analysis revealed a CS-responsive region of the INV promoter located between bp --2452 and --1880. A 5-base pair (bp) mutation of the AP-1 site (bp --2117 to --2111) within this responsive region abolished CS responsiveness, suggesting a role for the AP-1 complex in the regulation of INV transcription by CS. Electrophoretic mobility shift analysis demonstrated increased binding of nuclear extracts isolated from CS-treated NHK to AP-1 DNA as compared with vehicle-treated controls. Incubation of the nuclear extract with the appropriate antibodies showed that the AP-1 DNA-binding complex contained Fra-1, Fra-2, and Jun D. Western blots demonstrated that CS treatment increased the levels of Fra-1, Fra-2, and Jun D, and Northern analyses revealed that CS increased mRNA levels for these same AP-1 factors. These data indicate that CS, an endogenous lipid synthesized by keratinocytes, regulates the early stages of keratinocyte differentiation, and may do so through its ability to modulate levels of AP-1 proteins. -- Hanley, K., L. Wood, D. C. Ng, S. S. He, P. Lau, A. Moser, P. M. Elias, D. D. Bikle, M. L. Williams, and K. R. Feingold. Cholesterol sulfate stimulates involucrin transcription in keratinocytes by increasing Fra-1, Fra-2, and Jun D. J. Lipid Res. 2001. 42: 390--398.