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The Greig cephalopolysyndactyly syndrome (GCPS) is an autosomal dominant disorder affecting limb and craniofacial development in humans. GCPS-affected individuals are characterized by postaxial polysyndactyly of hands, preaxial polysyndactyly of feet, macroephaly, a broad base of the nose with mild hypertelorism and a prominent forehead. The genetic locus has been pinpointed to chromosome 7p13 by three balanced translocations associated with GCPS in different families. This assignment is corroborated by the detection of two sporadic GCPS cases carrying overlapping deletions in 7p13 (ref. 7), as well as by tight linkage of GCPS to the epidermal growth factor receptor gene in 7p12-13 (ref. 8). Of the genes that map to this region, those encoding T cell receptor-gamma, interferon-beta 2, epidermal growth factor receptor, and Hox1.4, a potential candidate gene for GCPS, have been excluded from the region in which the deletions overlap. Here we show that two of the three translocations interup the GLI3 gene, a zinc-finger gene of the GLI-Krüppel family already localized to 7p13 (refs 5, 6). The breakpoints are within the first third of the coding sequence. In the third translocation, chromosome 7 is broken at about 10 kilobases downstream of the 3' end of GLI3. Our results indicate that mutations disturbing normal GLI3 expression may have a causative role in GCPS.

A new in vitro test was developed to assess the trypanocidal activity of compounds against axenically grown Trypanosoma brucei bloodstream forms. Trypanosomes from continuous culture were exposed to series of drug dilutions in a microtiter plate. After an incubation time of 72 h at 37 degrees C, the pH indicator of the medium had changed its colour in non-inhibited cultures due to the production of pyruvate. Inhibited cultures showed less, if any, colour changes. Plates could be read by eye or using an enzyme-linked immunosorbent assay (ELISA) reader. Within the pH range of 7.0-7.5, the extinction values of phenol red at 560 nm showed a linear correlation with both the pH of the medium and the pyruvate concentration in the medium. By comparison of the decreases in extinction in test cultures with those in control cultures, IC50 values (drug concentrations causing 50% inhibition) could be determined. Minimal inhibitory concentrations (MICs) could be read by eye. The photometric test evaluation was compared with evaluation according to growth inhibition or to incorporation of radiolabelled hypoxanthine. The three methods of evaluation gave similar results.

The human gene encoding the myogenic determination factor myf3 (mouse MyoD1) has been mapped to the short arm of chromosome 11. Analysis of several somatic cell hybrids containing various derivatives with deletions or translocations revealed that the human MyoD (MYF3) gene is not associated with the WAGR locus at chromosomal band 11p13 nor with the loss of the heterozygosity region at 11p15.5 related to the Beckwith-Wiedemann syndrome. Subregional mapping by in situ hybridization with an myf3 specific probe shows that the gene resides at the chromosomal band 11p14, possibly at 11p14.3.

Detailed molecular definition of the WAGR region at chromosome 11p13 has been achieved by chromosome breakpoint analysis and long-range restriction mapping. Here we describe the molecular detection of a cytogenetically invisible 1-megabase deletion in an individual with aniridia, cryptorchidism, and hypospadias but no Wilms tumor (WT). The region of overlap between this deletion and one associated with WT and similar genital anomalies but no aniridia covers a region of 350-400 kilobases, which is coincident with the extent of homozygous deletion detected in tumor tissue from a sporadic WT. A candidate WT gene located within this region has recently been isolated, suggesting nonpenetrance for tumor expression in the first individual. The inclusion within the overlap region of a gene for WT predisposition and a gene for the best-documented WT-associated genitourinary malformations leads us to suggest that both of these anomalies result from a loss-of-function mutation at the same locus. This in turn implies that the WT gene exerts pleiotropic effect on both kidney and genitourinary development, a possibility supported by the observed expression pattern of the WT candidate gene in developing kidney and gonads.

Cytogenetic analysis has identified chromosome 11p13 as the smallest overlap region for deletions found in individuals with WAGR syndrome, which includes Wilms tumour (a recessive childhood nephroblastoma), aniridia, genito-urinary abnormalities and mental retardation. The underlying loci have since been resolved into an aniridia (AN2) locus at a telomeric position, and a locus of closely spaced genes or a single pleiotropic gene involved in genito-urinary tract abnormalities and Wilms tumour at a more centromeric position. Pulsed-field gel analysis of the 11p13 region has revealed the presence of several putative CpG islands, structures which are frequently associated with the 5' ends of expressed sequences, mainly housekeeping genes and some tissue-specific genes. Starting from a CpG island, we have now isolated four neighbouring CpG islands, all within 650 kilobases (kb), by means of two consecutive bidirectional jumps in rare-cutting restriction-enzyme jumping libraries. In two instances, flanking sequences were conserved in other species and RNA transcripts were identified. A complementary DNA clone isolated for one of them derives from an RNA highly expressed in fetal kidney, and is predicted to encode a Krüppel-like zinc-finger protein that is probably a transcription factor. The entire cDNA region is included in two partially overlapping homozygous deletions found in Wilms tumour DNA samples. Cloning of the breakpoints in one tumour revealed a deletion size of 170 kb, one-third of which is covered by the cDNA. The expression pattern and sequence of this cDNA could point to an important role for its corresponding gene in the normal development of the renal system as well as in Wilms tumour.

Chromosome 11p13 is frequently rearranged in individuals with the WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, and mental retardation) or parts of this syndrome. To map the cytogenetic aberrations molecularly, we screened DNA from cell lines with known WAGR-related chromosome abnormalities for rearrangements with pulsed field gel (PFG) analysis using probes deleted from one chromosome 11 homolog of a WAGR patient. The first alteration was detected in a cell line from an individual with aniridia, genitourinary anomalies, mental retardation, and a deletion described as 11p14.1-p13. We have located one breakpoint close to probe HU11-164B and we have cloned both breakpoint sites as well as the junctional fragment. The breakpoints subdivide current intervals on the genetic map, and the probes for both sides will serve as important additional markers for a long-range restriction map of this region. Further characterization and sequencing of the breakpoints may yield insight into the mechanisms by which these deletions occur.

Experimental C-fiber pain caused by radiant heat was applied to the skin area supplied by the left sural nerve of 20 subjects. Percutaneous electrical stimulation (PNS) was performed on the left sural nerve, the left superficial peroneal nerve and the right superficial radial nerve. Stimulation frequencies were: 3, 50, 100, 300, 500 and 1000 Hz. The analgesia resulting at the different stimulation sites was recorded according to a preset scale of estimation. Without considering the influence of the different frequencies, the best analgesic effects were reached if noxious heating and PNS were both performed on the left sural nerve; the anatomical conditions prevented us from distinguishing between the effects of possible peripheral blockade or spinal modification of pain. PNS of the superficial peroneal nerve seems to indicate spinal, possibly polysegmental, interactions between C-fiber pain and electrical stimulation of thick myelinated fibers. However, long loop effects may also play a part in local analgesia as demonstrated by PNS of the right radial nerve.

A long-range restriction map of part of the short arm of chromosome 11 including the WAGR region has been constructed using pulsed-field gel electrophoresis and a number of infrequently cutting restriction enzymes. A total of 15.4 Mbp has been mapped in detail, extending from proximal 11p14 to the distal part of 11p12. The map localizes 35 different DNA probes and reveals at least nine areas with features characteristic of HTF islands, some of which may be candidates for the different loci underlying the phenotype of the WAGR syndrome. This map will furthermore allow screening of DNA from individuals with WAGR-related phenotypes and from Wilms tumors for associated chromosomal rearrangements.

The proto-oncogene c-src, the cellular homolog of the Rous sarcoma virus (RSV) transforming gene v-src, is expressed in a tissue-specific and age-dependent manner. Its physiological function, although still unknown, appears to be more closely related to differentiation processes than to proliferation processes. To obtain more information about the physiological role of the c-src gene in cells, we have studied differentiation-dependent alterations using the human HL-60 leukaemia cell line as a model system. Induction of monocytic and granulocytic differentiation of HL-60 cells by 12-O-tetradecanoylphorbol-13-acetate (TPA) and dimethylsulfoxide (DMSO) is associated with an activation of the pp60c-src tyrosine kinase, but not with increased c-src gene expression. Control experiments exclude an interaction of TPA and DMSO themselves with the pp60c-src kinase.

Since Sylvatic rabies started in North Rhine-Westphalia in 1953 many epidemics have occurred, only in mid-mountain areas. As a characteristic, epidemics halted, in each case at the limit between big game (in south-east) and small game (in the north-west) hunting areas. The fact that rabies died out when reaching these limits is surprising for, according to the number of foxes killed in small game hunting areas, there was a fox density which usually does not allow the epidemic to stop. Explanation of this phenomenon could be the different hunting methods. Indeed in small game hunting areas 80% of killed foxes are cubs or sub-adults. Which means that most of the growing population is destroyed early enough, in contrast with big game hunting areas where less than half of the killed foxes are cubs or sub-adults. This is why in big game hunting areas, better conditions are found for rabies appearance than in the other type of hunting area. Studying the number of foxes killed, these relations are described for three regions of North Rhine-Westphalia. It is obviously very important in rabies control that, besides other measures, growing foxes are killed in priority.

Quantitative correlative investigations by means of light, immunofluorescence and electron microscopy carried out in the early phase of the disease on 58 patients (children and adults) with acute postinfectious glomerulonephritis (APGN) formed the basis of subtyping APGN into a starry sky type, a mesangial type and a garland type [Sorger et al. 1982 and 1983]. The subtypes also showed differences in the clinical picture. The garland type was of special interest since most patients had severe proteinuria. This caused us to follow-up the patients with these three subtypes (up to 10 years and 7 months). Proteinuria proved to be the most reliable follow-up parameter. A comparison of the three groups showed that proteinuria rapidly declined as a rule in the patients with the starry sky and the mesangial patterns. In the garland pattern there were also cases with a complete disappearance of proteinuria, especially in younger patients, but other patients still had a distinct proteinuria after months to years indicating a protracted or chronic course. The morphological findings of the rebiopsies correlated with the clinical courses, especially with the course of proteinuria. The three morphological subtypes are thus significant for estimating the prognosis of APGN, which is favorable as a rule in patients with the starry sky and mesangial types, but much more unfavorable in patients with the garland type. Even if fewer cases with demonstrated streptococcal etiology were found in the garland pattern group, i.e., among patients with the most uncertain prognosis, than in the remaining groups, these differences were not statistically significant. Therefore, our investigations do not provide any indications that different etiological factors are responsible for the three subtypes. The individual immune response of the host body is likely to be very much more decisive.

Chromosome translocations involving 11p13 have been associated with familial aniridia in two kindreds highlighting the chromosomal localization of the AN2 locus. This locus is also part of the WAGR complex (Wilms tumor, aniridia, genitourinary abnormalities, and mental retardation). In one kindred, the translocation is associated with a deletion, and probes for this region were used to identify and clone the breakpoints of the translocation in the second kindred. Comparison of phage restriction maps exclude the presence of any sizable deletion in this case. Sequences at the chromosome 11 breakpoint are conserved in multiple species, suggesting that the translocation falls within the AN2 gene.

Local analgesia can be produced by transcutaneous electrical stimulation of peripheral nerves. This is used in the treatment of chronic pain states. Its clinical effectiveness depends on two points; namely (1) the stimulation has to be perceptible, and (2) paresthesias elicited by TNS must be localized in the area of pain. To verify this in healthy subjects we produced an experimental pain by radiant heating of the skin and tested the analgesic effect of TNS. TNS stimuli parameters (duration, amplitude and frequency) were determined so that double blind conditions were given. Stimulation with small rectangular pulses showed the best analgesic effect especially at a stimulation rate of 100 Hz. The stimulation of various nerves showed that most of the analgesic effects depend on spinal level mechanisms but probably long loop effects are involved.

The WAGR (Wilms tumor, aniridia, genitourinary anomalies, and mental retardation) region has been assigned to chromosome 11p13 on the basis of overlapping constitutional deletions found in affected individuals. We have utilized 31 DNA probes which map to the WAGR deletion region, together with six reference loci and 13 WAGR-related deletions, to subdivide this area into 16 intervals. Specific intervals have been correlated with phenotypic features, leading to the identification of individual subregions for the aniridia and Wilms tumor loci. Delineation, by specific probes, of multiple intervals above and below the critical region and of five intervals within the overlap area provides a framework map for molecular characterization of WAGR gene loci and of deletion boundary regions.

The dorsal horn of the mammalian spinal cord contains interneurones which synthetize opioid peptides (endorphins) and release them on synaptic activation. Cells of origin of the spino-thalamic tract are in close functional relationship with these interneurones. The activation of the postulated endorphinergic mechanisms in the spinal cord could explain the selective reduction of painful stimuli following epidural application of opiate agonist.

The cellular onc-genes c-src and c-yes are expressed very differently during chicken embryonic development. The c-src mRNA and its translational product are detectable at high levels in brain extracts of chicken embryos and adult chickens, whereas muscle extracts show an age-dependent decrease in the amounts of c-src-specific mRNA and pp60c-src kinase activity. In contrast, the levels of c-yes mRNA in brain, heart, and muscle are relatively low in early embryonic stages and increase later on to values comparable to those found for liver, while in adult animals the pattern of c-yes expression is similar to that of the c-src gene. From the close correlation between the levels of pp60c-src, its enzymatic activity, and its corresponding mRNA at a given stage of development and in given tissues, it appears that the expression of pp60c-src is primarily controlled at the level of transcription. It is suggested that because of the different patterns of expression, the two cellular oncogenes, c-src and c-yes, play different roles in cell proliferation during early embryonic stages as well as in ensuing differentiation processes.