LMO2-associated clonal T cell proliferation in two patients after gene therapy for SCID-X1

We have previously shown correction of X-linked severe combined immunodeficiency [SCID-X1, also known as gamma chain (gamma(c)) deficiency] in 9 out of 10 patients by retrovirus-mediated gamma(c) gene transfer into autologous CD34 bone marrow cells. However, almost 3 years after gene therapy, uncontrolled exponential clonal proliferation of mature T cells (with gammadelta+ or alphabeta+ T cell receptors) has occurred in the two youngest patients. Both patients' clones showed retrovirus vector integration in proximity to the LMO2 proto-oncogene promoter, leading to aberrant transcription and expression of LMO2. Thus, retrovirus vector insertion can trigger deregulated premalignant cell proliferation with unexpected frequency, most likely driven by retrovirus enhancer activity on the LMO2 gene promoter.

Expression of the gene for transforming growth factor-beta in avian dyschondroplasia

Previous immunolocalisation studies of dyschondroplasia have indicated that there is a reduction in the number of growth plate chondrocytes containing the protein transforming growth factor beta 3 (TGF-beta 3). The reduction in TGF-beta 3 in dyschondroplasia is likely to be a direct result of a reduction in the expression of the TGF-beta 3 gene. mRNA was extracted from small (0.09 g) samples of growth cartilage from the proximal tibiotarsus of three-week-old broiler chicks. The cartilage samples contained cells from all three zones of the growth plate (proliferative, transitional and upper hypertrophic) and were collected from normal and dyschondroplastic growth plates. The dyschondroplastic growth plates were identified by an accumulation of transitional chondrocytes which were considered to be a result of a failure to differentiate to the hypertrophic phenotype. A semi-quantitative polymerase chain reaction (PCR) was used to estimate the quantity of mRNA specific for glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and for each of the three isoforms of TGF beta (TGF-beta 1, TGF-beta 2 and TGF-beta 3) in each of the cartilage samples. The levels of expression of mRNA for GAPDH, TGF-beta 1 and TGF-beta 2 were similar in the two groups, but the expression of TGF-beta 3 mRNA was significantly reduced in the samples from the dyschondroplastic growth plates. The reduction in TGF-beta 3 levels is thought to be associated with the failure of chondrocyte hypertrophy in dyschondroplasia, and provides in vivo evidence that TGF-beta 3 is part of the cascade of events associated with the differentiation of chondrocytes during endochondral ossification in the chick.

The State of Metropolitan Planning: Decline or Restructuring?

In this paper the dynamic relations between the state, society, and metropolitan planning are explored. The changing role and function of the state in the context of rapid restructuring of economic and social relations in Australia during the past decade are discussed, along with the impact of processes such as globalisation, cyclic recessions, and the growing assertion of local communities on the state. The influence of these processes on metropolitan planning, as an arm of the state which mediates between development interests and local communities, is then assessed from a theoretical perspective. Given the identified processes and changes, it is argued that metropolitan planning has become increasingly constrained in its ability to influence the nature and location of urban development in 1990s Australia.

The validity of this argument is examined against the case of metropolitan planning in Perth during the past decade. Three key aspects of the changing nature of planning in Perth are studied in detail: A 1987 proposal for a new metropolitan strategy; a 1990 adopted metropolitan plan which derived from the 1987 proposal; and several redevelopment initiatives currently under consideration. It is concluded that the Western Australian state—and subsequently metropolitan planning—have experienced significant challenges to their ability to influence urban change. The constraints imposed on metropolitan planning are simultaneously due to economic pressures ‘from above’ and community pressures ‘from below’. Finally, it is observed that this process possesses a regresive potential, and that metropolitan planning should restructure in order to respond effectively and equitably to recent economic and social changes.

Type II collagen expression in small, biopsy-sized samples of cartilage using a new method of RNA extraction

The extraction of mRNA from cartilage samples is complicated by the presence of proteoglycans and the low cellular density of the tissue. We required a method that would enable mRNA to be extracted from small biopsy-sized samples of cartilage. The method had to produce consistent results and sufficient RNA for Northern and PCR analysis. Methods of total RNA extraction, previously shown to be effective for cartilage, were compared with a new technique in which an oligo (dT) conjugated to biotin hybridises to the mRNA. The hybrids are captured with covalently coupled streptavidin paramagnetic particles. Samples of growth plate cartilage, including those specifically from the upper (proliferative and transitional) and lower (fully hypertrophic) zones, were collected and some were frozen at -70 degrees C. Samples for extraction by the paramagnetic method weighed approximately 80 mg and approximately 12 micrograms of mRNA was extracted from fresh tissue samples. The yield from similar frozen samples of the same weight was about a seventh of that from the fresh tissues. 5 micrograms of the mRNA from each sample was run on a gel, and a Northern blot was prepared and probed with a [32P]-labelled antisense RNA probe to type II collagen cDNA. A distinct band of type II collagen mRNA was detected (5.3 Kb) in the samples from the upper (proliferative and transitional) zone. The traditional methods of extracting RNA from cartilage required far greater quantities of tissue and the RNA produced was frequently degraded. The results obtained using the paramagnetic bead method precluded further trials with modification of the traditional methods of mRNA extraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Short-term outcome of mechanically ventilated infants weighing more than 2499 g at birth: a population based study

Very little data exist describing the neonatal outcome of infants of birthweight 2500 g or more who require mechanical ventilation. Our aim was to collect population-based data on such infants in New South Wales (NSW), and to monitor their neonatal morbidity, mortality to 1 year of age and the associated risk factors. The study group (NICUS infants) comprised all 341 infants weighing > 2499 g who were admitted to the seven neonatal intensive care units in New South Wales and mechanically ventilated for 4 h or more between 1 January and 31 December, 1987. Two groups of infants emerged: those who were preterm and mostly had hyaline membrane disease, and term and post-term infants for whom the most common problem was 'perinatal asphyxia'. The most important factors associated with dying were a birthweight of over 3499 g (OR = 2.6; CI 1.03-6.6) and a 1 min Apgar score < 4 (OR = 4.8; CI 1.4-16.9). Study group mothers were significantly more likely than all NSW mothers to have had a spontaneous abortion in the previous pregnancy (P < 0.01), a pre-existing medical condition or an obstetric complication in this pregnancy, or a Caesarean section for this delivery (P < 0.001). This is the first population-based study of high-risk neonates without congenital anomalies to clearly document the worsening prognosis associated with a birthweight over 3499 g. Further research should be directed towards identifying prenatal and perinatal factors which might minimize the morbidity and mortality in this group of babies.

Arthrodesis of the first metatarsophalangeal joint: a biomechanical study of internal fixation techniques

This study compares the strength and rigidity of four methods of internal fixation for arthrodesis of the first metatarsophalangeal joint. Ten matched pairs of cadaveric first rays were harvested and arthrodesis performed by one of four techniques: (1) planar excision of joint surfaces and fixation with crossed Kirschner wires, (2) planar excision of joint surfaces and internal fixation with a dorsal plate and screws, (3) planar excision of joint surfaces and internal fixation with an interfragmentary screw, or (4) excision of the joint surfaces using powered conical reamers and fixation with an interfragmentary lag screw. Biomechanical testing with a Bionix 858 materials testing machine was carried out, applying a plantar force utilizing principles of cantilever loading. Force applied and displacement of the arthrodesis were recorded. Of the four methods tested, bony preparation with power conical reamers and supplementary interfragmentary screw fixation was the most stable.

Evaluation of a genus reactive monoclonal antibody in rapid identification of Chlamydia trachomatis by direct immunofluorescence

This study compared the direct visualisation of elementary bodies in urogenital smears by the direct immunofluorescence test with the isolation of Chlamydia trachomatis in McCoy cell cultures treated with cytochalasin B. C trachomatis was isolated from 41 (16.4%) of 250 unselected specimens in McCoy cell cultures treated with cytochalasin B. Of the 41 culture positive specimens 37 (90%) were diagnosed by direct visualisation of elementary bodies in the smears using the direct immunofluorescence test. Four specimens were positive by isolation only and a further seven were positive by the direct immunofluorescence test only. Overall the direct immunofluorescence test had a sensitivity of 90% and a specificity of 97%. The presence of red blood cells or mucus or the use of barrier creams did not appear to interfere with the normal visualisation of elementary bodies using the direct immunofluorescence test.

Comparison of ELISA with virus isolation for the diagnosis of genital herpes

An enzyme linked immunosorbent assay (ELISA) system which detects and simultaneously types herpes simplex virus antigens in clinical specimens from patients with genital herpes has been compared with standard tissue culture isolation. Although more sensitive than a similar method previously described and also more sensitive than electron microscopy and immunofluorescence, ELISA did not detect all the viruses isolated in tissue culture. Costs were comparable. The speed of obtaining the result together with knowledge of the type causing infection are useful when antiviral chemotherapy is envisaged and when considering the likelihood of recurrences.

P1-purinoceptors mediate relaxation of the bovine bronchial artery

Adenosine 5'-triphosphate (ATP), adenosine 5'-diphosphate (ADP), adenosine 5'-monophosphate (AMP) and adenosine all relaxed the bronchial artery. All four purines tested were more efficacious than isoproterenol. Dipyridamole (10(-6) M) enhanced the relaxations due to adenosine and ATP while theophylline (10(-6) M) inhibited the relaxations due to adenosine and ATP. The results suggest the presence of P1-type purinoceptors in the bronchial artery of cattle.

Epithelial surfaces of the trachea and principal bronchi in the rat

The epithelial surfaces in the trachea and principal bronchi of healthy rats were examined by scanning electron microscopy. A system of four cell types, ciliated, microvillous, brush, and goblet cells, in this order of frequency, were found and intermediate type cells were not seen. An extensive area of the surface examined was covered by densely ciliated epithelium. The presence of other cell types beneath the cilia was confirmed by transmission electron microscopy. Areas up to 1 mm in diameter and randomly distributed were observed where microvillous cells predominated and only occasional ciliated cells were found. Most ciliated cells in these areas were adjacent to glandular openings or goblet cells. The larger microvilli of the brush cells were arranged in a coronal configuration elucidated by the scanning electron microscope. Preparatory techniques recently introduced for the examination of soft tissue in the scanning electron microscope facilitated the confirmation of cell types present and the microarchitecture of the epithelial surface.