Early progress in epigenetic regulation of endothelin pathway genes.

Control of gene transcription is a major regulatory determinant for function of the endothelin pathway. Epigenetic mechanisms act on tissue-specific gene expression during development and in response to physiological stimuli. Most of the limited evidence available on epigenetic regulation of the endothelin pathway focuses on the EDN1 and EDNRB genes. Examination of whole genome databases suggests that both genes are influenced by histone modifications and DNA methylation. This interpretation is supported by studies directed at detecting epigenetic action on the two genes. The clearest illustration of epigenetic factors altering endothelin signalling is DNA methylation-associated EDNRB silencing during tumourigenesis. This review summarizes our current understanding of epigenetic regulation of the endothelin pathway genes. LINKED ARTICLES This article is part of a themed section on Endothelin. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.168.issue-1.

Evaluation of transgenic approaches for controlling tuber moth in potatoes.

A wide spectrum of strategies to genetically engineer potato plants resistant to potato tuber moth, Phthorimaea operculella (Zeller), have been investigated. The potato cv Iwa was transformed with a range of genes under the transcriptional control of the CaMV 35S promoter using Agrobacterium-mediated gene transfer. The transferred genes encode protease inhibitors (spleen inhibitor and alpha1-antitrypsin inhibitor), biotin-binding proteins (avidin and streptavidin) and Cry proteins (crylAc9, cry1Ba1, crylCa5 and cry9Aa2). Of these three transgenic approaches, cry genes have proved the most useful. In order to control the expression of the cry genes in foliage and not in the tubers a light-inducible Lhca3 promoter from potato was also used. The interaction of different cry genes was investigated using an experimental approach to simulate gene pyramiding in potato. Potato plants transgenic for both the crylAc9 and cryAa2 genes were developed and evaluated to help provide a more durable resistance to potato tuber moth.

conZA8 encodes an abundant protein targeted to the developing macronucleus in Euplotes crassus.

During macronuclear development in the ciliate Euplotes crassus, micronuclear-derived chromosomes undergo a series of rearrangements that include polytenization, DNA splicing, chromosome fragmentation, and telomere addition and processing. Although cis-acting signals that may function in the regulation of these events have been characterized, the proteins that mediate these events have not yet been identified. To identify development-specific factors that may be involved in DNA rearrangement, we previously isolated clones of a number of genes that are expressed only during early macronuclear development. Here, we report the genomic and cDNA sequences of one of these genes, conZA8. The analysis indicates that the conZA8 gene encodes a novel, 468-amino acid, proline-rich protein. Antibodies were raised against both a recombinant form of the conZA8 protein and an internal peptide. Immunoblotting and immunofluorescence analyses indicated that the conZA8 protein is highly abundant, expressed only during the polytene chromosome stage of macronuclear development, and localized to the developing macronucleus. Possible functions of the conZA8 protein are discussed.

Conjugation-specific genes in the ciliate Euplotes crassus: gene expression from the old macronucleus.

Following mating or conjugation, the hypotrichous ciliate Euplotes crassus undergoes a massive genome reorganization process. While the nature of the rearrangement events has been well studied, little is known concerning proteins that carry out such processes. As a means of identifying such proteins, differential screening of a developmental cDNA library, as well as construction of a cDNA subtraction library, was used to isolate genes expressed only during sexual reproduction. Five different conjugation-specific genes have been identified that are maximally expressed early in conjugation, during the period of micronuclear meiosis, which is just prior to macronuclear development and the DNA rearrangement process. All five genes are retained in the mature macronucleus. Micronuclear, macronuclear, and cDNA clones of one gene (conZA7) have been sequenced, and the results indicate that the gene encodes a putative DNA binding protein. In addition, the presence of an internal eliminated sequence in the micronuclear copy of the conZA7 gene indicates that this conjugation-specific gene is transcribed from the old macronucleus.

Micronuclear and macronuclear sequences of a Euplotes crassus gene encoding a putative nuclear protein kinase.

The sequences of a 1.8-kbp macronuclear DNA molecule (V3), and the majority of its micronuclear counterpart, are reported. The macronuclear V3 DNA molecule contains an open reading frame that is interrupted by a single intron, while the micronuclear copy is interrupted by four internal eliminated sequences, one of which is located within the intron. The predicted protein product of the macronuclear V3 gene is a 471-amino acid polypeptide that is very similar to a group of protein-serine/threonine kinases from both plant and animal species, some of whose members appear to be involved in cell cycle or growth control.

Medical UV exposures and HIV activation.

This paper presents the first attempt to evaluate the potential of clinical UV exposures to induce the human immunodeficiency (HIV) promoter and, thus, to upregulate HIV growth in those skin cells that are directly affected by the exposure. Using the data for HIV promoter activation in vitro, we computed UVB and psoralen plus UVA (PUVA) doses that produce 50% of the maximal promoter activation (AD50). Then, using (a) literature data for UV transmittance in the human skin, (b) a composite action spectrum for HIV promoter and pyrimidine dimer induction by UVB and (c) an action spectrum for DNA synthesis inhibition by PUVA, we estimated the distribution of medical UVB and PUVA doses in the skin. This allowed us to estimate how deep into the skin the HIV-activating doses might penetrate in an initial and an advanced stage of UVB or PUVA therapy. Such analysis was done for normal type II skin and for single exposures. The results allow us to predict where in the skin the HIV promoter may be induced by selected small and large therapeutic UVB or PUVA doses. To accommodate changes in skin topography due to disease and UV therapy, our considerations would require further refinements. For UVB we found that, when the incident dose on the surface of the skin is 500 J/m2 (290-320 nm) (initial stage of the therapy), the dose producing 50% of the maximal HIV promoter activation (ADUVB50) is limited to the stratum corneum. However, with an incident dose of 5000 J/m2 (an advanced stage of the therapy), ADUVB50) may be delivered as far as the living cells of the epidermis and even to some parts of the upper dermis. For PUVA we found that, when the incident UVA doses are 25 or 100 kJ/m2 (320-400 nm) (an initial and an advanced stage of therapy, respectively), and the 8-methoxypsoralen concentration in the blood is 0.1 microgram/mL (the desired level), the combined doses to the mid epidermis (and some areas of the upper dermis) are well below the 50% HIV promoter-activating PUVA dose (ADPUVA50). Only under the worst scenario conditions, i.e. an exceptionally high drug concentration in the patient's tissues and localization of HIV in the nearest proximity to the skin surface, would the combined PUVA dose expected during photochemotherapy exceed ADPUVA50. These results suggest that the probability of HIV activation in the epidermis by direct mechanisms is higher for UVB than for PUVA treatment. However, complexities of the UV-inducible HIV activation and immunomodulatory phenomena are such that our results by themselves should not be taken as an indication that UVB therapy carries a higher risk than PUVA therapy when administered to HIV-infected patients.

Two supernumerary marker chromosomes, derived from chromosome 6 and 9, in a boy with mild developmental delay.

We report on a boy with two supernumerary marker chromosomes which were identified by fluorescence in situ hybridization and derived from chromosome 6 and 9. In lymphocytes, a mosaic karyotype was found: 46,XY (17%)/ 47,XY,r(6) (24%)/47,XY,r(9) (20%)/48,XY,r(6),r(9) (39%). Only minor dysmorphic features and mild developmental delay were present. Despite extensive fluorescence in situ hybridization studies using a large panel of probes, we were unable to characterize the marker chromosomes in more detail, mainly because no probes for the chromosome regions involved were available to us. In order to reach a better understanding of the clinical relevance of small supernumerary marker chromosomes, it will be necessary to create a widely available set of probes, covering all chromosome regions.

Partial trisomy and monosomy 8p due to inversion duplication.

Fluorescent in situ hybridization with probes specific for a chromosomal subregion and chromosome-specific libraries (chromosome painting) are important new methods for assessing chromosome rearrangements. In this paper we present four patients with additional chromosomal material on chromosome 8p who have been studied using G-banding techniques, chromosome painting and FISH with cosmid probes specific for the region 8p23.1-->8pter. In all cases we found a partial inversion duplication of 8p along with a deletion of the region 8p23.1-->8pter.

An estimation of squamous cell carcinoma risk from ultraviolet radiation emitted by fluorescent lamps.

The risk of squamous cell carcinoma (SCC) from ultraviolet radiation (UV) emitted by unfiltered fluorescent lamps was assessed. The assessment employed a mathematical power model based on human epidemiological data, which relates the SCC incidence in the United States white population to ambient solar UV. The annual numbers of new SCC on anatomical sites chronically exposed to solar UV (head/face/neck and hands) were estimated for indoor workers. Then the number of SCC that may be caused by additional UV exposure from indoor fluorescent lighting was estimated: the lifetime exposure of indoor workers to typical fluorescent lighting (if unfiltered) may add 3.9% (1.6-12%) to the risk from solar UV, resulting in the induction of an additional 1500 (600-4500) SCC per annum in the United States. This calculated projection must be compared with the 110,000 SCC caused by solar exposure. Thus, this analysis suggests there may be a small increased risk of SCC from exposure to UV-emitting fluorescent lamps.

[Experiences with arthrotomy of the knee in day care]. / Ervaringen met artrotomie van de knie in dagverpleging.

A retrospective study was performed of patients who had undergone an open knee procedure treated as day cases at the Regional Hospital of Zevenaar. An analysis was made of the rate of complications, whether complications were treated adequately, and how patients experienced an arthrotomy of the knee as a day-case procedure. Eighty-seven healthy patients aged 15 to 50 years underwent an arthrotomy of one knee as a day-case procedure, secondary to a diagnostic arthroscopy. The mean follow-up period was 8 months. Patients were reviewed by questionnaire, after which the knee was examined. The number of complications (6) was comparable with those reported in the literature. Complications within a few days after operation were reported to the GPs, who either treated themselves, or referred patients to the hospital. Of the patients 76% preferred this procedure to an operation in a clinical setting. The amount of pain suffered appears to be of great influence on the preference of the patient. The results of this study demonstrate that an arthrotomy of the knee is feasible as a day-care procedure, although extensive pre- and postoperative instructions to the patients may be improved.

Measles control in the urbanising environment.

The relationship between urbanisation and measles control is examined. In urban settings in developing regions measles is a disease of particular importance, since it tends to affect children at a younger age and with greater severity than in rural settings. A further finding in urban areas, especially peri-urban slums, is the lower measles vaccination coverage rates compared with rural regions. Factors identified as determinants of measles vaccination coverage among children under 2 years of age in urban areas include: home delivery; being born outside the urban setting; and length of stay in the city. These factors are probably related to the low socioeconomic status and lack of social integration experienced by new urban immigrants. A number of additional obstacles, such as distance, economic and cultural barriers, and inconvenient clinic hours all prevent parents from gaining easy access to vaccination services. In order to address the problems of measles control in expanding urban settings, a regional approach--with full integration of curative and preventive services--is called for. A more effective use of existing services will probably go a long way towards improving urban vaccination coverage with resultant measles control.

Survey of oral fluid therapy practices in South Africa.

The objectives of this study were to document the official oral fluid therapy (OFT) policies of all the ministries of health in South Africa and of the four provincial authorities, to determine what methods of OFT are used in hospitals providing paediatric care, to determine the OFT methods recommended by hospital staff for use at home, to establish the level of support for the idea of one national policy for OFT and to determine what senior academic paediatricians think about these issues. We conducted structured telephonic interviews of professional staff in charge of paediatric wards in 159 randomly selected hospitals providing general inpatient care. The hospitals were stratified as private, provincial and 'homeland'. We also interviewed the directors-general or the secretaries or their deputies in each ministry of health as well as directors of hospital services or their deputies in each one of the four provinces of the Republic. Lastly, we spoke to the academic heads of paediatric departments in each of the country's eight medical schools. The results show that the use of OFT for inpatient care of diarrhoeal disease is far from universal, and that the picture with regard to promotion of home OFT is even less favourable. We identified an unacceptable diversity in the OFT methods being promoted as well as a degree of resistance to the development of one national policy. We recommend that one policy, based on the recommendations of the South African Paediatric Association, be adopted by all health authorities in South Africa as a matter of urgency.(ABSTRACT TRUNCATED AT 250 WORDS)

Plain radiographs inadequate for evaluation of the cement-bone interface in the hip prosthesis. A cadaver study of femoral stems.

To determine whether plain radiographs accurately represent the true cement-bone interlock, a comparison was made between radiographs and macroscopic morphology on cross sections of 11 human femora into which a cemented endoprosthesis had been inserted. Four femora had been retrieved postmortem from patients with a hip arthroplasty, and seven cadaver femora were cemented under varying conditions. All the femora were radiographed and then cut for macroscopic inspection of the cement-bone interface with respect to gross interposition, depth of cement penetration, integrity of the bone bed, and lamellation of the cement.

An urban strategy towards the EPI.

Rapidly increasing urbanisation, fragmentation of health services, and civil unrest can constitute threats to the efficiency of the excellent immunisation services developed in most South African cities. Among children attending hospital outpatient departments are many who have escaped the net of the preventive services. A system has been developed to immunise all children entering the Red Cross War Memorial Children's Hospital, Cape Town, in whom immunisation is incomplete for age. The Community Health Liaison Group, which co-ordinates these and other health preventive/promotive activities in the hospital, is described.

The FDA report on intraocular lenses.

Clinical studies of intraocular lenses (IOLs) as investigational devices have been regulated in the United States by the Food and Drug Administration (FDA) since 9 February 1978. As of August 1982, data have been collected on more than one million IOLs implanted. During the last 12 months of the study, 409 000 IOLs were implanted. Visual acuity of 20/40 or better at one year after surgery was present in 85% of over 45 000 cases reviewed. Increasing patient age, surgical problems, postoperative complications, and adverse reactions were factors that reduced the visual acuity. The current trend in the USA is for implantation of posterior chamber and anterior chamber IOLs.

The FDA report on intraocular lenses.

Clinical studies of intraocular lenses (IOLs) as investigational devices have been regulated in the United States by the Food and Drug Administration (FDA) since February 9, 1978. As of August 1982, data have been collected on more than one million IOLs implanted. During the last 12 months of the study, 409,000 IOLs were implanted. Visual acuity of 20/40 or better at one year after surgery was present in 85% of over 45,000 cases reviewed. Increasing patient age, surgical problems, postoperative complications, and adverse reactions were factors that reduced the visual acuity. The current trend in the USA is for implantation of the posterior chamber and anterior chamber IOLs.

Beta-alanine and tanning polymorphisms.

1. Beta-alanine is found in mycelial walls of mature tan, but not immature white, stage of Morchella esulenta, nor in any stage of a permanently white mutant. 2. Beta-alanine is also found in hydrolysed water-extracts of human hair, the concentration being higher in blond than in dark brown, and in pigmented than in unpigmented hair. 3. Beta-alanine, added to tyrosinase-oxidized tyrosine, dopa, or dopamine has only a slight yellowing influence on the final black pigment; but when the amino group of tyrosine is combined with leucine, added beta-alanine produces stable tan pigments. 4. With L-alanine substituted for beta-alanine in this reaction, green pigment results. 5. Gelatin filters stained with the tan pigment allow solar heating of underlaying water more quickly than do those stained with the black pigment. Unstained filters allow such heating even more quickly. 6. Beta-alanine enhances production of tan pigment when heated with the phospholipid, lecithin. Implications for pigmentary adaptation, and formation of lipofuscin-like age pigments are discussed.