Changes of coat cover in primitive horses living on a reserve.

Changes in the coat cover are important for mammalian thermoregulation. This is especially true where variable environmental conditions exist throughout the seasons. Coat cover shedding is the replacement of old coat hair with new hair. The process differs in various equids. The aim of the study was to examine the changes in the coat of primitive Polish Konik horses living on a reserve in southeast Poland (50.6319° N). The reserve is located in a temperate climate. The mean temperature is below 0°C in winter (December 8 to March 9) and over 15°C in summer (June 8 to September 8). Five adult mares were included in the study. The study used a specific methodical approach to quantitatively assess coat cover changes. Photos were taken once every 2 wk throughout the whole year to document the state of the mares' coat. MultiScanBase software was used to analyze 260 photos. The percentage of the skin surface covered with short hair in relation to the surface of the body (without the head, neck, and limbs; short hair body [SHB]) was determined. To assess the topography of coat changes, surface parts covered with short hair within 6 regions of the body (shoulder, back, chest, loins, belly, and hindquarters; short hair part [SHP]) were considered separately. The regression coefficient was calculated for the SHB and the air temperature. Correlations in SHP and SHB between the left and right sides of the body were determined. The correlations within the right side of the body concerned particular SHP. As the results show, the coat changes take place at the same time on both sides of the horse's body. In spring, the winter hair is shed, and in the fall, the winter hair grows in longer. High regression (0.901; < 0.0001) proved that air temperature strongly affected the coat changes. The most important increase of SHB occurs in April and the first half of May, whereas the main decrease of SHB takes place in September. Changes between SHP are highly correlated (0.967-0.994; < 0.05). Spring and fall coat changes demonstrate that the shoulders, back, and loins require the winter cover for a longer time than the chest and belly, whereas the hindquarters are the least demanding in this respect. The phenomenon may be associated with, among others, the stronger effect of rain and snow on the upper parts of the body.

Human peripheral blood CD8+ CD28- T cells of renal allograft recipients do not express FOXP3 protein.

INTRODUCTION: In recent studies, the FOXP3 molecule has been suggested to be a marker of a suppressor subset of human CD8+ CD28- T cells based on correlations between the level of its mRNA and allograft function. Because this transcriptional factor produces a protein, we suggest that these correlations should focus on the FOXP3 protein. The aim of our study was to evaluate whether FOXP3 protein was present in cells of the CD8+ CD28- population in the peripheral blood of renal allograft recipients and whether the level of CD8+ CD28- FOXP3+ cells correlated with allograft function. METHODS: The study was performed on 30 renal allograft recipients with uneventful stable courses (n=18) or biopsy-proven chronic rejection (n=12). The immunosuppression was based on cyclosporine (n=12) or rapamycin (n=9). Peripheral blood mononuclear cells isolated from recipient blood samples were labeled with anti-CD8 and anti-CD28 MAbs conjugated with fluorochromes. After incubation, washing, and labeling using a PE anti-human FOXP3 Kit, we determined the percentage of cells by flow cytometry. RESULTS: FOXP3 protein expression was not observed either in the CD8+ CD28- population, or the whole populations of CD8+ or CD28- cells among patient groups. CONCLUSIONS: The expression of FOXP3 protein in CD8+ CD28- cells seems to be of a questionable value as a diagnostic tool for allograft function, it is probably not a marker for the CD8+ CD28- T cell subset.

The influence of immuosuppressive therapy on the development of CD4+CD25+ T cells after renal transplantation.

A growing number of studies suggest that CD4(+)CD25(+) T regulatory (Treg) cells play a significant role to downregulate the immune response to alloantigens. In this study, we investigated the possible influence of immunosuppressive therapy, including cyclosporine (CsA) or rapamycin (sirolimus), on the level of CD4(+)CD25(+), CD4(+)CD25(+)FOXP3(+), and CD4(+)CD25(+)CTLA-4(+) T cells in the peripheral blood of renal allograft recipients. The study was performed on renal allograft recipients who displayed uneventful stable courses (RAR-S; n = 15) versus biopsy-proven chronic rejection (RAR-CH; n = 12). The patients were divided based on the immunosuppressive protocol: group 1 (prednisone+CsA+Aza) and group II (prednisone+sirolimus). The control group consisted of 10 healthy blood donors. We examined the expression of CD4, CD25, CTLA-4, and Foxp3 in peripheral blood T cells. Flow cytometry was performed with a FACSCalibur (BD Biosciences) instrument with data analyzed using Cell Quest software. The percentage of CD4(+)CD25(+)Foxp3(+) T cells in rapamycin (sirolimus) treated patients did not differ from that observed in healthy individuals, but was significantly higher compared with CsA-treated patients. CsA therapy resulted in a reduction in the percentage of CD4(+)CD25(+)CTLA-4(+) and CD4(+)CD25(+)Foxp3(+) regulatory T cells after renal transplantation in both groups (RAR-S and RAR-CH) compared with patients treated with rapamycin or to healthy donors. The type of immunosuppressive therapy (with or without calcineurin inhibitors) may have an important role in tolerance induction and graft function.

Comorbidity of hyperactivity-impulsivity-inattention and conduct problems: risk factors in social, affective, and academic domains.

Children showing a comorbid behavior pattern of hyperactivity-impulsivity-inattention and conduct problems (HIA + CP) were contrasted to children having only an internalizing and externalizing behavior pattern (I + E) and matched controls. Children displaying the HIA + CP behavior pattern were at greater risk on a number of outcome measures in social and academic domains beginning in Grade 3 and continuing into Grade 4. The most marked differences among the three groups were found on peer measures of rejection and friendship and teacher ratings of social skills. On average, almost two-thirds of the HIA + CP group were rejected by their peers compared to one-third of the I + E group and only 12.5% controls. Over 70% of the HIA + CP group had no reciprocated friendships from Grade 3 to Grade 4 compared to less than half of the I + E group and approximately one-fourth of controls. Contrary to much theorizing in the literature, the HIA + CP and I + E groups showed average levels of academic self-concept and did not differ from controls in on measures of social self-concept and academic self-concept and general self-esteem. These findings were interpreted in light of positive illusory biases and the established link between aggressive behavior and egotism. The current article offers partial support for Lynam's (1996) notion of the "fledgling psychopath."

Discrepancy between definitions of learning disabilities and school practices: an empirical investigation.

Students referred by general education teachers to school study teams (SSTs) were evaluated for learning disabilities (LD) eligibility. We classified children as LD on the basis of a WISC-III Full Scale IQ of 82 or higher and a 22-point discrepancy between IQ and any WRAT-R achievement score. Research decisions were then contrasted with actual school-based decisions regarding the child as LD. Over half of the students referred to SSTs were certified by the schools as LD, yet less than half of these school-certified students with LD evidenced the aptitude-achievement discrepancy required by the state. Examination of the cases called LD by the schools revealed that children were classified as LD on the basis of low absolute achievement, regardless of whether or not a discrepancy existed. Moreover, in cases where a discrepancy was found but the school did not classify the child as LD, that child evidenced significantly higher achievement, despite exhibiting the requisite 22-point discrepancy. The school-identified students with LD constituted an extremely heterogeneous group, including students with mental retardation along with a substantial number who failed to qualify for any special education services. Findings are discussed in terms of the discrepancy between criteria specified in state regulations and what the committee members at the school site seemed to use in classifying children with LD.

Learning disabilities, low achievement, and mild mental retardation: more alike than different?

Children identified with learning disabilities (LD), low achievement (LA), or mild mental retardation (MMR) were contrasted on 41 measures of ability, academic achievement, social skills, problem behavior, academic engaged time, perceptual-motor skills, and school history. Both multivariate, univariate, and meta-analytic comparisons among the three groups showed relatively large differences on measures of aptitude and achievement, with the LD group scoring higher on measures of cognitive ability than the LA and MMR groups and the LA group showing higher tested academic achievement than the LD and MMR groups. Teacher ratings of academic competence showed similar levels of functioning for the LD and LA groups. No differences among the groups were found on measures of social skills, problem behaviors, or academic engaged time, or on most indices reflecting school history. Results were interpreted in light of studies contrasting LD and LA groups. Comparisons with earlier studies were difficult in light of demographic differences in samples and the lower cognitive and academic functioning of children in the present study. The current study showed that 61% of the LD group could be differentiated from the LA group, with LD-MMR and LA-MMR differentiation levels being 68.5% and 67.5%, respectively.

The labyrinth of IDEA: school decisions on referred students with subaverage general intelligence.

A sample of 150 children referred to Student Study Teams was assessed with a psychometric battery. Behavioral and academic ratings were obtained from teachers. Forty-three children scored at or below 75 on the WISC-III. We examined schools' subsequent classification decisions to ascertain how schools dealt with low-IQ students with academic and behavioral problems. Schools reached decisions regarding 35 of the children: Only 6 were classified as having mental retardation, and 18, as having learning disabilities. Findings were discussed in terms of (a) decline in identification rates of mild mental retardation and (b) the extent to which school decisions adhere to the research criteria.

Determination of the transbilayer distribution of fluorescent lipid analogues by nonradiative fluorescence resonance energy transfer.

We measured the nonradiative fluorescence resonance energy transfer between 7-nitro-2,1,3-benzoxadiazol-4-yl (NBD) labeled lipids (amine labeled phosphatidylethanolamine or acyl chain labeled phosphatidylcholine) and rhodamine labeled lipids in large unilamellar dioleoylphosphatidylcholine vesicles. Two new rhodamine labeled lipid analogues, one a derivative of monolauroylphosphatidylethanolamine and the other of sphingosylphosphorylcholine, were found to exchange through the aqueous phase between vesicle populations but not to be capable of rapid transbilayer movement between leaflets. Energy transfer from NBD to rhodamine was measured using liposomes with symmetric or asymmetric distributions of these new rhodamine labeled lipid analogues to determine the relative contributions of energy transfer between donor and acceptor fluorophores in the same (cis) and opposite (trans) leaflets. Since the characteristic R0 values for energy transfer ranged from 47 to 73 A in all cases, significant contributions from both cis and trans energy transfer were observed. Therefore, neither of these probes acts strictly as a half-bilayer quencher of NBD lipid fluorescence. The dependence of transfer efficiency on acceptor density was fitted to a theoretical treatment of energy transfer to determine the distances of closest approach for cis and trans transfer. These parameters set limits on the positions of the fluorescent groups relative to the bilayer center, 20-31 A for NBD and 31-55 A for rhodamine, and provide a basis for future use of these analogues in measurements of transbilayer distribution and transport.

Synthesis, purification, and characterization of 2,4,6-trinitrophenyl-UDP-galactose: a fluorescent substrate for galactosyltransferase.

Glycosyltransferases enzymatically transfer monosaccharides from sugar-nucleotides to complex oligosaccharide chains and, as cell surface molecules, exhibit receptor-like activity. We have modified the substate UDP-galactose to produce a compound that has useful absorbance and fluorescence properties upon binding to galactosyltransferase (GalTase). Using strategies similar to those for preparing fluorescent ATP analogs, we were able to synthesize 2,4,6-trinitrophenyl-5'-UDP-galactose (TUG). In solution, the absorbance properties of TUG are pH dependent, with absorbance maxima at 260, 408, and 453 nm and an isobestic point at 353 nm. In the presence of soluble GalTase extracted from bovine milk, TUG exhibited an excitation maximum at 368 nm with emission maxima at 436 and 533 nm; in the absence of GalTase only the 533-nm peak was present. Under enzymatic conditions, TUG acted as a competitive substrate of UDP-galactose with GalTase. Under noncatalytic conditions, the fluorescence emission of TUG at 436 nm increased monotonically with Gal-Tase concentration, with a half-maximal response at approximately 4 microM. This compound may be useful for quantifying GalTase function as both an enzyme and a cell adhesion molecule.