Predictive validity of a national examination for medical graduates in the People's Republic of China

National examinations for medical graduates were introduced on an experimental basis in the People's Republic of China in 1982. To estimate the predictive validity of the National Medical Examination (NME), an investigation of the postgraduate competence of a sample of the participating examinees was conducted in 1984. The sample consisted of 1,717 of the 4,995 graduates from 13 medical colleges who had taken the initial NME. Their scores on the NME and the ratings given them by directors of postgraduate programs in nine aspects of clinical competence were compared by frequency distribution and product-moment correlation coefficients. Scores on the NME were consistent with measures of postgraduate clinical competence and, as a whole, correlated significantly with the ratings of clinical competence, supporting the use of the score on the NME as a predictor of postgraduate clinical competence. However, the extent of the relationship between the NME score and postgraduate clinical competence varied according to the specialty program of postgraduate medical training.     

An effective method for quantitative evaluation of proteins adsorbed on biomaterial surfaces

An effective method for the quantitative evaluation of proteins adsorbed on biomaterial surfaces has been developed. First, the kinetic behavior of a range of human fibrinogen (Fib) adsorbed onto polystyrene (PS) films was investigated by using a reflectometry interference spectroscopy setup. The specific molecular number of adsorbed proteins, N(p,) was then defined. According to the definition, the numbers of Fib molecules adsorbed on PS films were calculated. An atomic force microscope (AFM) was used to scan the lateral distribution of the Fib molecules adsorbed on the PS films. From the AFM images, the practical specific molecular numbers were obtained by direct counting of the molecules. In order that the adsorbed number of Fib molecules on a unit area of the PS films could be counted easily, the solution concentration of proteins was reduced to 5 ag/mL (10(-18)g/mL). There was good consistency between the numbers calculated with the formula defined by us and the numbers counted from AFM images. Therefore, the results of the present study prove the validity of our definition of the specific molecular number of adsorbed proteins and the effectiveness of the reflectometry interference spectroscopy-based method for quantitative evaluation of adsorptive proteins.     

Identification of a type 1 diabetes-associated CD4 promoter haplotype with high constitutive activity

CD4 is a candidate gene in autoimmune diseases, including Type 1 diabetes mellitus (T1DM), because the CD4 receptor is crucial for appropriate antigen responses of CD4(+) T cells. We previously found linkage between a CD4-1188(TTTTC)(5-14) promoter polymorphism and T1DM. In the present study, we screened the human CD4 promoter for mutations and identified three frequent single nucleotide polymorphisms (SNPs): CD4-181C/G, CD4-521C/G and CD4-1050T/C. The SNPs are in strong linkage disequilibrium (LD) and association with the CD4-1188(TTTTC)(5-14) alleles, and we observed nine CD4 promoter haplotypes, of which four are frequent. We genotyped the SNPs in 253 Danish T1DM families (1129 individuals) and found evidence for linkage and association of a CD4 (A4(-1188)T(-1050)G(-521)C(-181)) haplotype to T1DM. In reporter studies, we show that (1) the T1DM-associated CD4 haplotype encodes high constitutive promoter activity and (2) the CD4-181G variant encodes higher stimulated promoter activity than the CD4-181C variant. This difference is in part neutralized in the frequently occurring CD4 promoter haplotypes by the more upstream genetic variants. Thus, we report functional impact of a novel CD4-181C/G SNP on stimulated CD4 promoter activity and the identification of a novel CD4 haplotype with high constitutive promoter activity that is linked and associated with T1DM.     

Galectin-1 and galectin-3 in chronic pancreatitis

Galectin-1 and galectin-3 have important functions in cell-cell interactions, cell adhesion to extracellular matrix, the organization of extracellular matrix, and tissue remodeling. To assess their potential role in chronic pancreatitis (CP), we examined their expression by Northern blot analysis, in situ hybridization, immunohistochemistry, and Western blot analysis in normal and CP pancreatic tissues. Northern blot analysis revealed a 4.5-fold increase of galectin-1 mRNA (p < 0.01) and a 3.8-fold increase of galectin-3 mRNA (p < 0.01) in CP samples compared with normal controls. In situ hybridization analysis of normal pancreas indicated low abundance of galectin-1 mRNA in fibroblasts, whereas galectin-3 mRNA was moderately present in ductal cells. CP samples exhibited moderate to intense galectin-1 mRNA signals in fibroblasts, whereas galectin-3 mRNA signals were intense in the cells of ductular complexes and weak in the degenerating acinar cells. In addition, intense galectin-1 and galectin-3 mRNA signals were present in nerves of normal and CP samples. Immunohistochemistry showed a distribution pattern of galectin-1 and galectin-3 similar to that described for in situ hybridization. Relative quantification of galectin-1 and galectin-3 protein by immunoblotting revealed an increase of 3.2-fold and 3.0-fold, respectively, in CP compared with normal controls. There was a significant correlation between galectin-1 and fibrosis and between galectin-3 and fibrosis and the density of ductular complexes. Up-regulation of galectin-1 in fibroblasts and galectin-3 in ductular complexes suggests a role of these lectins in tissue remodeling in CP. Galectin-1 might participate in ECM changes, whereas galectin-3 seems to be involved in both ECM changes and ductular complex formation.     

Results of rhabdomyosarcoma treatment in a developing country

Fifty-one children (median age: 4.5 years; 4 months-16 years) diagnosed with rhabdomyosarcoma were treated in our center between 1980-1999. The primary sites were head and neck in 31.4%, the genito-urinary system in 21.6%, and extremities in 9.8% of the patients. The histopathologic subtypes were embryonal in 80.4%, alveolar in 9.8%, and undifferentiated in 9.8%. The majority of the patients were considered group III (47%) and group IV (25.5%) according the criteria of the Intergroup Rhabdomyosarcoma Study (IRS). Primary total tumour resection was performed in only 27.5% of the patients. The patients were treated with assigned regimens of IRS II and IRS III protocols. Radiotherapy was applied to 92.1% of the patients. Thirty-four patients (66.7%) were lost to follow up, and of the remaining 17 patients, 7 patients (41.2%) died, relapse occurred in 9 patients (52.9%) and 10 patients (58.8%) are alive. The percentage of cases lost to follow up during the first 10 years and the following 9 years of the study were 77.4% and 50%, respectively. In compliance with cancer treatment remains a major problem in developing countries.     

Molecular cloning and sequence analysis of full-length cDNAs encoding new group of Cyn d 1 isoallergens

BACKGROUND: Cyn d 1, the major allergen of Bermuda grass pollen, contains some acidic/basic isoforms. The N-terminal amino acid sequences of some acidic Cyn d 1 isoforms were found to be different from those of Cyn d 1 cDNA clones identified previously. METHODS: A predicted 17-meric oligonucleotide probe was designed to fish the unidentified isoallergen cDNAs out of BGP cDNA library. The reactive clones were isolated and verified by sequencing. Two of them were expressed in the yeast Pichia pastoris to obtain recombinant Cyn d 1 proteins. RESULTS: All four cDNA clones encode the full-length Cyn d 1 with mature proteins of 244 amino acid residues. A 97-99% identity was found among the deduced amino acids of these four clones while an 86% identity was elicited between the four clones and the ones previously identified. The predicted isoelectric focusing (pI) values of the newly identified Cyn d 1s are acidic while pIs of the previously identified Cyn d 1s are basic. The two recombinant acidic Cyn d 1 proteins possess the epitopes recognized by mouse and rabbit polyclonal anti-Cyn d 1 antibodies, and have human IgE-binding capacity as revealed by immunodot assay. CONCLUSIONS: The present study identified full-length cDNAs encoding new isoallergens of Cyn d 1, and separated Cyn d 1 gene into an acidic group and a basic group.     

The orchestration of the sensory-motor systems: Clues from Neuropsychology

Research over the last several decades has led to clear and empirically tractable proposals about the representation of conceptual knowledge in the brain. Here we argue that there are already sufficient data from neuropsychology to strongly constrain extant hypotheses about the representation of conceptual knowledge. One constraint imposed by these neuropsychological data is that recognition of actions and understanding of objects do not necessarily depend on the ability to produce object-associated actions. This conclusion compels a reconsideration of the role played by motor planning and/or execution processes in action and object recognition and understanding.