Engulfed cell remnants, and not cells undergoing apoptosis, constitute the LE-cell phenomenon

The LE cell has been one of the first immunological signs of active systemic lupus erythematosus, included into the ACR criteria. LE cells consist of a phagocyte engulfing material of disputed origin, which was interpreted as either cellular remnants from necrotic cells or as early apoptotic cells. It is well established that LE cell formation is dependent on autoantibodies against the linker histone H1. In view of this fact, we investigated whether anti-histone H1 antibodies and LE cell positive sera bound to cells where apoptosis had been induced by gliotoxin or actinomycin D or which were necrotic after heating. Necrotic cell remnants, but not (early) apoptotic cells were bound by anti-histone H1 antibodies and LE cell positive sera, establishing that the process of LE cell formation, which is dependent on anti-H1 binding, leads to engulfment of necrotic (or late apoptotic) material, but not of early apoptotic cells.

Apoptosis in Vero cells infected with Akabane, Aino and Chuzan virus

Akabane, Aino and Chuzan virus are arthropod-borne (arbo) viruses mainly associated with reproductive failures in cattle. We investigated apoptosis in Vero cells (C-1586) infected with Akabane, Aino and Chuzan virus. The fragmentation of chromosomal DNA was simultaneously detected with the progress of cytopathic effect from 48 hr to 72 hr post infection, depending on viruses. Although the treatment of cycloheximide blocked apoptosis in Vero cells infected with three viruses, actinomycin D did not prevent DNA oligomerization, thus indicating that de novo viral protein synthesis is critical for viral apoptosis. In addition, the activation of caspase-3 was also detected in Vero cells by indirect fluorescent assay. From the present results, it is of future interest whether apoptotic characteristics of these viruses are related to pathogenecity in vivo.

[Relapses in children with nephroblastoma--a single centre experience]

The aim of the study was to assess the incidence of relapse and outcome of treatment in children with nephroblastoma relapse.

MATERIAL AND METHODS

In the years 1989-2002 at our centre 67 children were treated for nephroblastoma. Patients were divided into two subgroups. Group I comprised 25 children treated in accordance with the SIOP-9 programme, whilst group II consisted of 42 patients following the SIOP 93-01 protocol.

RESULTS

In group I, five children had relapse diagnosed: local in 2, pulmonary in 2 and cerebral in one case. Two of the cases were diagnosed during the treatment, and the other 3 after 1 to 19 months from the completion of treatment. In group II relapse was diagnosed in 4 children: local in 2 and pulmonary in 2 cases. One case was diagnosed while on treatment, and the other 3 were diagnosed 1,2 and 4 months after completion of treatment. Among the children who followed the SIOP-9 programme three patients died, while among those following SIOP 93-01 two patients died.

CONCLUSIONS

The prognosis in patients who relapsed remains uncertain. The histological type of tumour and the moment of relapse occurrence are significant prognostic factors.

Gene transfer of baculoviral p35 by adenoviral vector protects human cerebral neurons from apoptosis

Apoptosis plays an important role in neuronal cell death in both chronic and acute human neurological diseases, including ALS, Huntington's disease, cerebral ischemia, and HIV encephalopathy. We evaluated the ability of an extremely powerful antiapoptotic agent, baculoviral p35, to prevent apoptosis and cell death of human cerebral neurons that undergo severe neurotoxic changes in a culture system when treated with agents that are implicated in human neurological disorders, that is, tumor necrosis factor (TNFalpha) and the HIV proteins Tat and gp120. P35 is a potent broad-spectrum antiapoptotic protein derived from baculovirus, that inhibits nearly all caspases, and has other antiapoptotic actions as well. Adenoviral vectors expressing p35 (Ad. p35) or a control gene (lacZ) efficiently transduced human neurons. Treatment of control cultures with the toxic agents TNFalpha, TNFalpha plus Actinomycin D, or Tat and gp120, induced neurotoxicity and death of neurons. Transduction of neurons with Ad. p35 blocked apoptosis, and eliminated cell death due to TNFalpha, or Tat and gp120. Viral vector transfer of the p35 gene efficiently protects human neurons from TNFalpha, or Tat and gp120-induced apoptosis and cell death. These results suggest that p35 transduction of neurons by viral vectors could be therapeutically useful in the treatment of human neurodegenerative diseases.

Protective effect of distillate and redistillate of cow's urine in human polymorphonuclear leukocytes challenged with established genotoxic chemicals

OBJECTIVE

From the ancient period cow's urine has been used as a medicine. In Veda, cow's urine was compared to the nectar. In Susrut, several medicinal properties of cow's urine have been mentioned and are known to cause weight loss, reversal of certain cardiac and kidney problems, indigestion, stomach ache, edema, etc. However, the literature and scripture did not mention the antigenotoxic properties of cow's urine.

METHODS

In the present investigation, the antigenotoxic/antioxidant properties of cow's urine distillate and redistillate were studied in vitro. The antioxidant status and volatile fatty acid levels were determined. Actinomycin-D (0.1 micromol/L) and hydrogen peroxide (150 micromol/L) were used for inducing DNA strand break with 0.1% DMSO as negative control. Dose for the antigenotoxic effect of cow's urine was chosen from the dose response study carried out earlier.

RESULTS

Both actinomycin-D and H202 caused statistically significant DNA unwinding of 80% & 75% respectively (P < 0.001) as revealed by fluorimetric analysis of DNA unwinding (FADU), and the damage could be protected with the redistilled cow's urine distillate (1, 50 & 100 microL) in simultaneous treatment with genotoxic chemicals.

CONCLUSION

The redistillate of cow's urine was found to possess total antioxidant status of around 2.6 mmol, contributed mainly by volatile fatty acids (1500 mg/L) as revealed by the GC-MS studies. These fatty acids and other antioxidants might cause the observed protective effects.

Gene expression profiles of apoptotic neurons

The multigenic program underlying neuronal apoptosis is mostly unknown. To study the program, we used genome-scale screening by oligonucleotide microarrays during serum and potassium deprivation-induced apoptosis of cerebellar granule neurons. From the 8740 genes interrogated by the arrays, 423 genes were found to be regulated at both the transcriptional and the posttranscriptional level and segregated into distinct clusters. Semantic clustering based on gene ontologies showed coordinated expression of genes with common biological functions and metabolic pathways. Among the genes implicated in apoptotic cerebellar granule neurons, 70 were in common with those differentially expressed in cortical neurons exposed to amyloid beta-protein, indicating the existence of common mechanisms responsible for neuronal cell death. Our results offer a genomic view of the changes that accompany neuronal apoptosis and yield new insights into the underlying molecular basis.

Mucositis and airway obstruction in a pediatric patient

Pediatric patients undergoing induction regimens of chemotherapy may require intubation and mechanical ventilation either for respiratory failure or airway compromise as a complication of their therapy. We describe a case of difficult airway management resulting from pseudomembrane formation in a 16-yr-old girl. The patient was undergoing induction chemotherapy for stage IV rhabdomyosarcoma and developed severe mucositis that led to progressive airway obstruction.

Immunogenicity of the histidine-to-tyrosine staphylococcal enterotoxin B mutant protein in C3H/HeJ mice

Staphylococcal enterotoxin B (SEB) is a common cause of food poisoning and toxic shock. A safe and effective vaccine is needed to protect against the superantigenic effects of this toxin. We previously constructed and produced an apparently nontoxic SEB mutant having four histidine-to-tyrosine substitutions in positions 12, 32, 105, and 121. In the present study, we found that this H1.2.3.4 SEB mutant had low toxicity, was able to induce high levels of specific IgG antibodies, and protected mice in both the actinomycin D-primed and intranasal SEB intoxication model systems, despite the absence of detectable specific IgM and IgA antibodies. We propose further development of the H1.2.3.4 recombinant protein as a potential anti-SEB vaccine candidate.

Coordinate down-regulation of cartilage matrix gene expression in Bcl-2 deficient chondrocytes is associated with decreased SOX9 expression and decreased mRNA stability

The anti-apoptotic protein Bcl-2 has been shown to function in roles unrelated to apoptosis in a variety of cell types. We have previously reported that loss of Bcl-2 expression alters chondrocyte morphology and modulates aggrecan expression via an apoptosis-independent pathway. Here we show that Bcl-2 is required for chondrocytes to maintain expression of a variety of cartilage-specific matrix proteins. Using quantitative, real-time PCR, we demonstrate that Bcl-2-deficient chondrocytes coordinately down-regulate genes coding for hyaline cartilage matrix proteins including collagen II, collagen IX, aggrecan, and link protein. The decrease in steady-state level of these mRNA transcripts results, in part, from decreased mRNA stability in Bcl-2-deficient chondrocytes. Transcriptional regulation is also likely involved because chondrocytes with decreased Bcl-2 levels show decreased expression of SOX9, a transcription factor necessary for expressing the major cartilage matrix proteins. In contrast, chondrocytes constitutively expressing Bcl-2 have a stable phenotype when subjected to loss of serum factor signaling. These cells maintain high levels of SOX9, as well as the SOX9 targets collagen II and aggrecan. These results suggest that Bcl-2 is involved in a pathway important for maintaining a stable chondrocyte phenotype.

Gestational trophoblastic syndrome: an audit of 112 patients. A South African experience

Gestational trophoblastic disease (GTD) represents a spectrum of histologically distinct entities including molar pregnancy and choriocarcinoma. The incidence of GTD varies in different parts of the world with high incidences in countries like Japan (2 / 1000 pregnancies). With the advent of sensitive assays for detection of serum beta human chorionic gonadotrophin (HCG) and ultrasound, GTD can now be detected earlier in pregnancy. To date no studies have been reported from South Africa regarding the epidemiology, management, and outcome of patients with GTD. This study was a retrospective audit based on 112 patients with GTD treated at King Edward VIII Hospital, Durban, South Africa. Clinical records of patients were reviewed with regards to presentation, investigation, management and outcome. Of 112 patients, there were 78 patients (70%) with hydatidiform mole and 34 patients (30%) with choriocarcinoma. The mean age of patients was 28.5 years (SD 8.1 years). The majority of patients were Black females (94.6%) while 4.4% were Asian and 1% Coloured females. The most common presenting symptom was vaginal bleeding (93.8%). There were 74 patients (66.7%) who had a previous normal term pregnancy and only two patients (1.8%) had previous molar pregnancies. Suction curettage was the main treatment modality for patients with molar pregnancy while choriocarcinoma was treated primarily with chemotherapy. A total of 72 percent of patients with molar pregnancy and 28 percent with choriocarcinoma had complete remission after initial treatment. Twelve patients died during the course of treatment mainly due to late presentation and advanced metastatic disease. Complete cure was achieved in 89% of patients. Age, parity, previous history, initial uterine size, presence of theca-lutein cysts, and initial betaHCG concentration was not found to be prognostic for persistent trophoblastic disease. In the present study, the incidence of molar pregnancy and choriocarcinoma was 1.2 / 1000 and 0.5 / 1000 deliveries, respectively. This is much lower than those quoted from countries such as Japan. However, the incidence quoted from our study may be overestimated as this was a hospital-based study and most of the uncomplicated deliveries occur in referring centers. Only 20% of patients in this study were above the age of 35 years with a mean age of 28.5 years. The majority of patients were of Black African ethnic origin mainly due to the fact that our hospital is a referral center for Black patients. Similar to other studies, the majority of patients with molar pregnancy were treated with suction curettage while the majority of patients with choriocarcinoma were treated with chemotherapy. Overall, spontaneous remission was achieved in 60% of patients with molar pregnancy and an overall complete cure was achieved in 89% of patients.

Mechanisms of bFGF and NT-4 potentiation of necrotic neuronal death

The effects of neurotrophic factors on necrotic neuronal death are controversial. In this study we found that both neurotrophin-4 (NT-4) and basic fibroblast growth factor (bFGF) potentiated necrotic neuronal death caused by exposure to oxygen-glucose deprivation or iron-citrate (Fe) in cortical cultures. However, there were significant differences in the actions of the two neurotrophic factors. Neurotrophin-4 protected against apoptotic neuronal death, while bFGF had no effect on apoptotic death in these cultures. Furthermore, potentiation of oxygen-glucose deprivation induced necrotic death by NT-4 required pretreatment (24 h), while pretreatment with bFGF had no effect. However, acute treatment with bFGF during oxygen-glucose deprivation did potentiate neuronal death. Both neurotrophic factors potentiated free radical mediated necrotic neuronal death induced by exposure to Fe. However, the RNA synthesis inhibitor, actinomycin-D, blocked the injury potentiation by NT-4, but not that caused by bFGF. Also, NT-4, but not bFGF, potentiated Fe induced necrotic death in pure neuronal cultures. Expression of mRNA for FGF receptors FGFR1 and FGFR2 was observed at high levels in astrocytes. The results indicate that the injury enhancing effects of bFGF are acute, while those of NT-4 require prolonged exposure and new protein synthesis. Furthermore, the effects of bFGF appear to be mediated through actions on astrocytes, while NT-4 appears to act directly on neurons. The fact that neurotrophic factors from two distinct families can potentiate neuronal death by two different mechanisms suggests that such injury potentiation may be a common concern regarding the use of neurotrophic factors.

A 3'-UTR variant of the inducible porcine hsp70.2 gene affects mRNA stability

Large individual differences were observed in the abundance of transcripts from the hsp70.2 gene in primary fibroblast cultures sampled from 15 different pigs. While previously described functional promoter variants of this gene can partly account for the high variability of heat-induced increased abundance of transcripts, they are unrelated to the observed highly variable absolute amounts of hsp70.2 transcripts. Comparative sequence analysis revealed an alteration of the 3'-untranslated region (3'-UTR) sequences in these samples. The variant 3'-UTR allele proved to increase the half life of the hsp70.2 mRNA in reporter gene assays. It is suggested that the cellular stress response is significantly affected by the action and interaction of both promoter and 3'-UTR variants of the hsp70.2 gene.

[Chromosome CPD(PI/DAPI)- and CMA/DAPI-banding patterns in Allium cepa L]

Chromosome banding patterns of Allium cepa L. were obtained by using fluorochrome combinations chromomycin A3 (CMA) + 4',6-diamidino-2-phenylindole (DAPI), DAPI + actinomycin D (AMD) and propidium iodide (PI) + DAPI. In A. cepa, telomeric heterochromatin displayed dull fluorescence after staining with DAPI and DAPI/AMD. After staining with the GC-specific CMA and AT-specific DAPI, the CMA-positive fluorescence of the NOR region and the telomeric bands of C-heterochromatin was observed. In combination with DAPI, PI, a dye with low AT/GC specificity, produced almost uniform fluorescence of chromosomal arms and heterochromatin, whereas the NOR-adjoining regions displayed bright fluorescence. Denaturation of chromosomal DNA (95 degrees C for 1-3 min) followed by renaturation in the 2 x SSC buffer (37 degrees C, 12 h) altered the chromosome fluorescence patterns: specific PI-positive bands appeared and the contrast of CMA-banding increased. Bright fluorescence of the NOR and adjoining regions was also observed in the case. Three-minute denaturation led also to a bright PI-positive fluorescence of telomeric heterochromatin. The denaturation of chromosomal DNA before staining results in changes of the DAPI fluorescence pattern and in the appearance of DAPI fluorescence in GR-rich NOP regions. The mechanisms underlying the effects of denaturation/renaturation procedures on chromosome banding patterns obtained with different fluorochromes are discussed.

[Effect of cloned DNA fragment from Streptomyces chrysomallus No.2 on metabolism in Streptomyces strains]

The effects on cloned DNA fragment carrying an actinomycin resistance determinant on physiological processes in streptomyces strains with various potencies in producing this antibiotic, their inactive mutants, and model strain of Streptomyces lividans 66 were studied. This fragment was shown to modulate bacterial resistance to actinomycin and biosynthesis of antibiotics.

Transitional cell carcinoma of the urinary bladder following exposure to cyclophosphamide in childhood

With the increasing survival of children with malignancies, the long-term effects of chemotherapies are now becoming important and one of these dreadful long-term complications is the development of a second malignancy. Described here is a case of transitional cell carcinoma of the bladder developing 8 years following exposure to cyclophosphamide for the treatment of embryonal rhabdomyosarcoma.