First comprehensive low-density horse linkage map based on two 3-generation, full-sibling, cross-bred horse reference families

Two 3-generation full-sibling reference families have been produced and form a unique resource for genetic linkage mapping studies in the horse. The F(2) generations, now comprising 61 individuals, consist of 28- to 32-day-old embryos removed nonsurgically from two pairs of identical twin mares. The same stallion sired all F(2)s such that the two full-sibling families are half-sibling with respect to each other. The families are crossbred to maximize levels of heterozygosity and include Arabian, Thoroughbred, Welsh Cob, and Icelandic Horse breeds. Milligram quantities of DNA have been isolated from each embryo and from blood samples of the parents and grandparents. The families have been genotyped with 353 equine microsatellites and 6 biallelic markers, and 42 linkage groups were formed. In addition, the physical location of 85 of the markers is known, and this has allowed 37 linkage groups to be anchored to the physical map. The inclusion of dams in the genotyping analysis has allowed the generation of a genetic map of the X chromosome. Markers have been assigned to all 31 autosomes and the X chromosome. The average interval between markers on the map is 10.5 cM, and the linkage groups collectively span 1780 cM. The results demonstrate the benefits for horse linkage mapping studies of genotyping on these unique full-sibling families, which comprise relatively few individuals, by the generation of a comprehensive low-density map of the horse genome.

Topical use of papaya in chronic skin ulcer therapy in Jamaica

The objective of the study was to determine the prevalence of the use of the fruit (papaya) of Carica papaya as topical ulcer dressings by registered nurses in the Spanish Town Hospital (STH), Kingston Public Hospital (KPH) and the University Hospital of the West Indies (UHWI), Jamaica. A ten-item pretested self-administered questionnaire was distributed to 285 randomly selected registered nurses at the UHWI, KPH and STH. There was a 72% response rate. The prevalence of topical papaya use among the respondents was 75%. Comments from the users of papaya suggested that topical application of the unripe fruit promoted desloughing, granulation and healing and reduced odour in chronic skin ulcers. It was cost effective. Papaya was considered to be more effective than other topical applications in the treatment of chronic ulcers. There was some difficulty in preparation of the fruit and occasionally a sensation of burning was reported by the patients. There was concern about the use of a non-sterile, non-standardised procedure but there were no reports of wound infection from its use. Papaya is widely used by nurses as a form of dressing for chronic ulcers and there is need for standardisation of its preparation and application.

Vascular endothelial growth factor mRNA expression in minimal change, membranous, and diabetic nephropathy demonstrated by non-isotopic in situ hybridisation

AIM

To investigate vascular endothelial growth factor (VEGF) mRNA expression in glomerular disease in the context of heavy proteinuria.

METHODS

Non-radioisotopic in situ hybridisation was performed using a cocktail of 12 deoxyoligonucleotides complementary to VEGF mRNA labelled during solid phase synthesis with 2,4-dinitrophenyl. Archival renal biopsies were studied from cases of minimal change nephropathy, membranous nephropathy, diabetic nephropathy, and controls, matched for age, sex, race, and storage time. Hybrid detection used NBT/BCIP colorimetric development.

RESULTS

More VEGF mRNA positive glomerular cells per unit cross sectional diameter were seen in minimal change nephropathy (mean (SEM), 19.35 (1.5)) compared with controls (12.6 (1.73)), p < 0.01. In contrast, fewer were seen in diabetic nephropathy (5.93 (0.97)) compared with controls (9.97 (1.25)), p < 0.03. Analysis of membranous nephropathy (10 (1.62)) showed no difference from controls (10.98 (1.51)), NS. In addition, in minimal change nephropathy there was a significant correlation between 24 hour protein excretion at the time of biopsy and the number of VEGF mRNA cells per glomerulus (r = 0.08, p = 0.01).

CONCLUSIONS

Using non-radioisotopic in situ hybridisation, VEGF mRNA is almost exclusively expressed by visceral glomerular epithelial cells. Abnormal numbers of cells are seen in both minimal change and diabetic nephropathy. As VEGF exists in a number of functionally distinct isoforms, further study of qualitative VEGF isoform expression in diagnostic groups is indicated.

Report of the International Equine Gene Mapping Workshop: male linkage map

The goal of the First International Equine Gene Mapping Workshop, held in 1995, was the construction of a low density, male linkage map for the horse. For this purpose, the International Horse Reference Family Panel (IHRFP) was established, consisting of 12 paternal half-sib families with 448 half-sib offspring provided by 10 laboratories. Blood samples were collected and DNA extracted in each laboratory and sent to the Lexington laboratory (KY, USA) for dispatch in aliquots to 14 typing laboratories. In total, 161 markers (144 microsatellites, seven blood groups and 10 proteins) were tested for all families for which the sire was heterozygous. Genealogies and typing data were sent for analysis to the INRA laboratory (Jouy-en-Josas, France) according to a specific format and entered into a database with input verification and output processes. Linkage analysis was performed with the CRIMAP program. Significant linkage was detected for 124 loci, of which 95 were unambiguously ordered using a multipoint analysis with an average spacing of 14.2 CM. These loci were distributed among 29 linkage groups. A more comprehensive analysis including synteny group data and FISH data suggested that 26 autosomes out of 31 are covered. The complete map spans 936 CM.

Computerized histomorphometric assessment of protocol renal transplant biopsy specimens for surrogate markers of chronic rejection

BACKGROUND

Chronic transplant rejection has emerged as the commonest cause of long-term renal allograft failure, and early identification of those grafts at risk could allow the targeting of specific therapies aimed at delaying this process. This study explores the usefulness of quantitative immunohistochemistry in defining biopsy-based surrogate markers of allograft damage.

METHODS

A consecutive series of 52 renal transplant recipients immunosuppressed with cyclosporine were studied. Needle core transplant biopsies were performed at 1, 3, and 6 months postoperatively. Immunostaining for collagen III, and smooth muscle actin, tenascin, and infiltrating leukocytes was performed using an indirect immunoperoxidase technique. The interstitial area stained (%) was measured using a semiautomatic image analysis system. The results were related to glomerular filtration rates (GFR) measured at 6, 12, and 24 months after transplantation using rank correlation coefficients.

RESULTS

The area fraction of immunostained collagen III correlated with 6-month GFR (r=-0.42, P=0.005) and was predictive of 12-month GFR (r=-0.32, P=0.03). An area fraction of immunostained collagen III of >40% at 6 months was associated with a significantly lower GFR at 24 months, compared with a percentage area of < or =40% (31+/-4 versus 45+/-4 ml/min/1.73 m2, P=0.01). Furthermore, a collagen III of >40% at 6 months identified patients who were at risk of progressive deterioration in graft function.

CONCLUSIONS

Grafts with poorer long-term function can be predicted using 6-month protocol biopsy specimens immunostained for collagen III. This should prove to be a useful ad interim surrogate marker of allograft damage in studies addressing the effects of new immunosuppressive agents on the development of chronic rejection.

Proteinuria induces tubular cell turnover: A potential mechanism for tubular atrophy

BACKGROUND

Proteinuria and tubular atrophy have both been closely linked with progressive renal failure. We hypothesized that apoptosis may be induced by tubular cell exposure to heavy proteinuria, potentially leading to tubular atrophy. Apoptosis was studied in a rat model of "pure" proteinuria, which does not induce renal impairment, namely protein-overload proteinuria.

METHODS

Adult female Lewis rats underwent intraperitoneal injection of 2 g of bovine serum albumin (BSA, N = 16) or sham saline injections (controls, N = 8) daily for seven days. Apoptosis was assessed at day 7 in tissue sections using in situ end labeling (ISEL) and electron microscopy. ISEL-positive nuclei (apoptotic particles) were counted in blinded fashion using image analysis with NIH Image. Cell proliferation was assessed by detection of mRNA for histone by in situ hybridization, followed by counting of positive cells using NIH Image.

RESULTS

Animals injected with saline showed very low levels of apoptosis on image analysis. BSA-injected rats had heavy proteinuria and showed both cortical and medullary apoptosis on ISEL. This was predominantly seen in the tubules and, to a lesser extent, in the interstitial compartment. Overall, the animals injected with BSA showed a significant 30-fold increase in the number of cortical apoptotic particles. Electron microscopy of tubular cells in a BSA-injected animal showed a progression of ultrastructural changes consistent with tubular cell apoptosis. The BSA-injected animals also displayed a significant increase in proximal tubular cell proliferation. This increased proliferation was less marked than the degree of apoptosis.

CONCLUSION

Protein-overload proteinuria in rats induces tubular cell apoptosis. This effect is only partially balanced by proliferation and potentially provides a direct mechanism whereby heavy proteinuria can induce tubular atrophy and progressive renal failure.

A synteny map of the horse genome comprised of 240 microsatellite and RAPD markers

To generate a domestic horse genome map we integrated synteny information for markers screened on a somatic cell hybrid (SCH) panel with published information for markers physically assigned to chromosomes. The mouse-horse SCH panel was established by fusing pSV2neo transformed primary horse fibroblasts to either RAG or LMTk mouse cells, followed by G418 antibiotic selection. For each of the 108 cell lines of the panel, we defined the presence or absence of 240 genetic markers by PCR, including 58 random amplified polymorphic DNA (RAPD) markers and 182 microsatellites. Thirty-three syntenic groups were defined, comprised of two to 26 markers with correlation coefficient (r) values ranging from 0.70 to 1.0. Based on significant correlation values with physically mapped microsatellite (type II) or gene (type I) markers, 22 syntenic groups were assigned to horse chromosomes (1, 2, 3, 4, 6, 9, 10, 11, 12, 13, 15, 18, 19, 20, 21, 22, 23, 24, 26, 30, X and Y). The other 11 syntenic groups were provisionally assigned to the remaining chromosomes based on information provided by heterologous species painting probes and work in progress with type I markers.

Two SINE families associated with equine microsatellite loci

BLAST searches of 61 equine microsatellite sequences revealed two related families of retroposons. The first family included seven markers, all of which showed significant homology to the Equine Repetitive Element-1 (ERE-1) Short Interspersed Nucleotide Element (SINE) sequence. Length of homology ranged from 76 to 171 bases with identities to the ERE-1 consensus sequence ranging from 71% to 83%. The second family referred to as Equine Repetitive Element-2 (ERE-2) has a consensus sequence that showed homology to ERE-1 over approximately 60 bases. These 60 bases comprised subunit I. Sequence comparisons for the two retroposons led to the identification of a subunit II, subunit III, as well as the tRNAser subunit. The subunit structure of ERE-1 was tRNAser-I-II. By contrast, the subunit structure of ERE-2 was I-III-III. The nine markers related to ERE-2 showed homology lengths ranging from 84 to 163 bases with identities ranging from 75% to 99%. In addition to being present in microsatellites, ERE-2 appeared in three separate equine genes. It occurred in an intron of DNA-PK, in an untranslated region as well as in the promoter of PGHS, and in the coding region of PAM. The amino acids corresponding to the ERE-2 sequence in PAM were not present in the human or mouse PAM homologs. These amino acids associated with the ERE-2 sequence were present on the cytosolic side of the transmembrane domain of the PAM enzyme. Microsatellite markers in the ERE-1 and ERE-2 families were found throughout the genus equus and also for rhinoceros, indicating that the appearance of both retroposons predates the divergence of equids from the other perissodactyls. The markers did not amplify in human or bovine DNA. This indicated that ERE-1 and ERE-2 are, at least, perissodactyl specific.

Visceral glomerular epithelial cell DNA synthesis in experimental and human membranous disease

BACKGROUND

Membranous nephropathy (MN) is a 'non-proliferative' glomerulonephritis. However, visceral glomerular epithelial cell (vGEC) proliferating cell nuclear antigen staining and increased glomerular histone mRNA in passive Heymann nephritis (PHN), suggest that vGECs may enter the cell cycle and undergo DNA synthesis. We used in situ hybridisation for histone mRNA, an S-phase specific marker, to investigate this possibility and identify the cellular origin of histone mRNA in PHN and MN.

METHODS

PHN was induced in 16 Sprague-Dawley rats. There were 8 saline/serum controls. 12 animals were sacrificed on days 5 and 10. Renal biopsies from 10 proteinuric cases with MN and matched controls were studied.

RESULTS

Day-5 Heymann animals demonstrated more S-phase cells/glomerulus than controls (0.53 +/- 0.09 vs. 0.195 +/- 0.045; p < 0.01). Glomerular S-phase cells were also increased in patients compared to controls (0.24 +/- 0.07 vs. 0.04 +/- 0.018; p < 0.03). In both experimental and human MN, the peripheral location and morphology of glomerular histone mRNA-positive cells was typical of vGECs.

CONCLUSION

The results in PHN indicate that vGECs recently injured with antibody and complement enter into the cell cycle and undergo DNA synthesis. The S-phase vGECs in MN may indicate the persistence of immune injury. Whether or not this process leads to cell replication is open to question.

Teaching and maintaining behavior management skills with nursing assistants in a nursing home

This article describes a nursing staff training program in basic behavior management skills and a formal staff management system to encourage the application of these basic skills on the nursing unit. Behavioral skills training consists of a 5-hour in-service followed by three weeks of on-the-job training to ensure accurate application of behavior management skills. Following training, a staff management system is used to facilitate long-term use of the skills. Components of the staff management system include supervisory monitoring of the nursing assistants (NAs) by licensed practical nurses (LPNs), NA self-monitoring, verbal and written performance feedback, and incentives.

Frequency of the SCID gene among Arabian horses in the USA

Severe combined immunodeficiency disease (SCID) of horses is an autosomal, recessive hereditary disease occurring among Arabian horses. The genetic defect responsible for this disease was recently identified as a 5-basepair deletion in the gene encoding DNA-protein kinase catalytic subunit (DNA-PKcs). Horses with one copy of the gene appear normal, while horses with two copies of the gene manifest the disease. The present report describes a PCR-based test for detection of the gene defect and the results from testing 250 randomly selected Arabian horses. The frequency of SCID gene carriers was 8.4% (21/250). Based on the gene frequency reported here, the authors would expect 0.18% (1 out of 567) of Arabian foals to be affected with SCID based on a random breeding population.

A microcosm study on remediation of explosives-contaminated groundwater using constructed wetlands

Anaerobic degradation of TNT and TNB in gravel systems was rapid and similar to removal rates in parrot feather lagoons. Planted and unplanted anaerobic gravel systems were the only treatments that provided significant reduction of RDX and HMX. Planted systems with parrot feather had no effect on removal rates of explosives in anaerobic gravel systems. Reciprocating wetlands were not effective in biodegrading RDX or HMX, but were very efficient at removing COD. A scaled-up concept for bioremediating contaminated groundwater can be envisioned with the data obtained in the current study. The effectiveness of anaerobic gravel systems indicate an anaerobic subsurface-flow constructed wetland can be established as the primary treatment for remediation with C added to the influent or step fed down the length of the wetland. Another option would be to add compost as a more permanent source of C to the gravel substrate. With time, the need for C supplementation may be reduced with the C exudates and redox lowering potential of certain plants like canarygrass (Phalaris arundinacea). As a secondary treatment, a reciprocating wetland would appear to be a logical choice to quickly remove C released in effluent waters of the anaerobic wetland.

Ring test for the determination of N-terminal valine adducts of styrene 7,8-oxide with haemoglobin by the modified Edman degradation technique

A ring-test was organised between three laboratories using different versions of the modified Edman degradation technique for the gas chromatographic-mass spectrometric determination of N-terminal valine adducts of styrene 7,8-oxide. The analyses were performed on a sample of human haemoglobin reacted in vitro with styrene 7,8-oxide and on a set of five haemoglobin samples from mice dosed by i.p. injection of styrene. Strong correlations between the haemoglobin adduct determinations of the different laboratories were observed. However, covariance analysis revealed different slopes for the dose-response curves, indicating differences for the calibration of the reference globin or reference peptide.

Determination of cis-thymine glycol in DNA by gas chromatography-mass spectrometry with selected ion recording and multiple reaction monitoring

A novel method for the determination of cis-thymine glycol in DNA has been developed, using gas chromatography-mass spectrometry with selected ion recording or multiple reaction monitoring. The procedure involves acidic hydrolysis of DNA in the presence of the internal standard cis-[2H3]thymine glycol, followed by derivatisation with N-methyl-N-(tert.-butyldimethylsilyl)trifluoroacetamide. The method was validated on DNA that had been oxidatively modified in vitro by radiation treatment, and was then applied to determine cis-thymine glycol in human placental DNA. Background levels of 5.45+/-2.98 ng cis-thymine glycol/mg DNA were observed in the human samples.