Evaluation of hot saline solution and restriction endonuclease techniques in cytogenetic studies of Cycloneda sanguinea L. (Coccinellidae)

The goal of the present study was to determine if simple methods, especially hot saline solution (HSS) and MspI and HaeIII restriction endonucleases, which do not require special equipments, may be helpful in studies of genetic variability in the lady beetle, Cycloneda sanguinea. The HSS method extracted the heterochromatin region, suggesting that it is composed mostly of DNA rich in A-T base pairs. However, the X and y chromosomes were resistant to HSS banding. These bands facilitated the identification of each chromosome. In this study, we used the restriction endonucleases with different G-C base target sequences: MspI C/GGC and HaeIII GG/CC. The use of restriction enzyme MspI did not show an effect on the autosomal chromosomes. On the other hand, the sex pair showed a pale staining, to help in the recognition of these chromosomes. HaeIII produced characteristic bands which were identified all along the chromosomes, facilitating the identification of each chromosome. Based on these results, we can consider the heterochromatin being heterogeneous. The findings obtained here, using different chromosomal banding techniques, may be useful in the identification of intraspecific chomosome variability, specifically in Coccinellidae (Coleoptera) chromosomes, even without special equipment.

X-chromosomal inactivation skewing in blood cells is associated with early development of lung / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To observe the relationship between skewed X-chromosomal inactivation (SXCI) and development of lung cancer in females.</p><p><b>METHODS</b>DNA was isolated from peripheral blood cells from patients with primary lung cancer (n = 148) and control subjects (n =289). Exon 1 of androgen receptor ( AR) gene was amplified, with its products from different alleles resolved on denaturing polyacrylamide gels and visualized by silver staining. The corrected ratio (CR) between products from different AR alleles before and after Hpa II pretreatment was calculated. All statistical tests were two-sided.</p><p><b>RESULTS</b>With CR> or = 10 adopted as the criterion, SXCI was found more frequently in the younger patients ( C50 years; 7. 9%) than in the controls of the same age group (1. 2% ; P = 0. 046). The SXCI frequency, however, were not significantly different between the old patients ( > 50 years; 4. 5% ) and the controls of the same age group (5. 4% ; P =0. 488). Whether taking CR> or =3 or CR> or =10 as the criteria, the average ages of the patients with SXCI were more than 10 years younger than those without SXCI (P < 0. 05).</p><p><b>CONCLUSION</b>SXCI in blood cells is associated with early development of lung cancer in females.</p>

Polymorphism of CYP1A1 gene Msp I site in the Mongolian and Han nationality populations of Inner Mongolia of China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the polymorphism of CYP1A1 gene Msp I site in the Mongolian and Han nationality populations of Inner Mongolia.</p><p><b>METHODS</b>The PCR-restriction fragment length polymorphism(PCR-RFLP) technique was used to analyze the genotypes of CYP1A1 gene Msp I site in 80 subjects of Mongolian nationality and 120 subjects of Han nationality among whom there is no blood relationship each other.</p><p><b>RESULTS</b>The genotype frequency of CYP1A1 gene Msp I site showed that the wild-type, heterozygote, homozygous variants were 35.0%, 48.7%, 16.3% and 33.3%, 52.5%, 14.2% respectively distributions of Mongolian nationality and Han nationality population, and the Chi-square tests showed that there was no significant difference between the two groups.</p><p><b>CONCLUSION</b>The genotype frequency distributions of CYP1A1 gene Msp I site did not exhibit the obvious difference between Mongolian nationality and Han nationality population of Inner Mongolia.</p>

Association of genetic polymorphism in GH gene with milk production traits in Beijing Holstein cows.

Associations were analysed between polymorphisms of the growth hormone gene (GH-MspI) (localized in intron 3) and milk production traits of Beijing Holstein cows (a total of 543 cows). Polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method was used for identification of various genotypes. Frequencies of genotypes were 0.77, 0.21 and 0.02 for A/A, A/B and B/B, respectively. The frequency of the GH A allele is 0.875. The results of the least squares means show that in all three lactations, the GH A/A cows yielded more milk (P less than 0.01 for lactation I and P less than 0.05 for lactations II and III), whereas A/B cows showed higher milk fat content than A/A individuals (P less than 0.05 for lactations I and II, and P less than 0.01 for lactation III). The A/A cows yielded more fat than A/B individuals (P less than 0.01 only in lactation I). The A/A cows yielded more milk protein than A/B individuals (P less than 0.01 for lactations I, II, and III). The A/A cows produced milk of higher protein content than of A/B individuals (P less than 0.05 only in lactation II).

Application of PCR-based restriction fragment length polymorphism for the identification of mycobacterial isolates.

BACKGROUND AND OBJECTIVE: Conventional identification of mycobacteria is achieved by standard biochemical tests that are time consuming, laborious and is not always conclusive. This study was thus undertaken to standardize a simple, rapid and cost-effective polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) using primers coding for the 16S - 23S rRNA spacer region to identify the mycobacterial isolates to the species level. METHODS: The PCR with primers targeting the 16S-23S rRNA spacer region was standardized using the standard mycobacterial strains and applied on 51 clinical isolates. The PCR amplified products were subjected to RFLP using the restriction enzymes, Hae III, MspI and BstXI. The results obtained were compared with those of conventional biochemical tests. RESULTS: PCR was sensitive to detect 2.5 pg of H37Rv DNA (370 bp for slow grower mycobacteria) and 1.5 pg of M. fortuitum DNA (450 bp for rapid grower mycobacteria). Based on the PCRRFLP products obtained the 51 mycobacterial isolates were classified into 41 slow growers and 10 rapid growers. Among the 41 slow growers, 40 were identified as M. tuberculosis, one as M. xenopi and 10 rapid growers as M. fortuitum. INTERPRETATION AND CONCLUSION: PCR using primers targeting the 16S-23S rRNA spacer region was a reliable tool for rapid identification of mycobacterial isolates into slow and rapid growers within 4 h of isolation and further speciation by PCR-RFLP within 6-8 h.

Plasma activated coagulation factor VII and Msp I polymorphism in elderly patients with coronary heart disease / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the association of activated coagulation factor VII(F7a) and its gene Msp I polymorphism with coronary heart disease in elderly patients.</p><p><b>METHODS</b>This was a case-control study, and the method of candidate gene was adopted. F7 genotypes were identified with polymerase chain reaction amplified genomic deoxyribonulieic acid (DNA) and Msp I restriction fragment length polymorphism analysis, and the level of plasma F7a was detected with recombinant tissue factor method for 108 elderly patients with coronary heart disease and 120 sex- and age-matched healthy control subjects.</p><p><b>RESULTS</b>(1) Plasma F7a levels was significantly higher in elderly patients with coronary heart disease than in healthy control subjects (2.88 +/- 0.62 vs 2.58 +/- 0.60 microg/L, P < 0.05), and was significantly higher in old myocardial infarction than in stable angina pectoris (3.12 +/- 0.62 vs 2.76 +/- 0.60, P < 0.05). F7a was shown to be a risk factor for coronary heart disease in elderly patients by Logistic regression analysis (OR=1.21 P < 0.05). (2) The allelic frequencies were in accordance with Hardy-Weinberg equilibrium. The results suggested that the distribution of genotype and allelic frequencies in the groups displayed no significant difference, and there was no difference between the subgroups of coronary heart disease in elderly patients, either (P > 0.05). (3) F7a level was significantly higher in RR genotype than in Q allele carriers (2.72 +/- 0.60 vs 1.98 +/- 0.59 microg/L, P < 0.05) and was associated with F7 gene polymorphism.</p><p><b>CONCLUSION</b>Plasma F7a level may be an independent risk factor of coronary heart disease in elderly patients, and it may be influenced by the Msp I polymorphism of F7 gene.</p>

Clonality Study in Carcinosarcomas and Malignant Mixed Epithelial Tumors

BACKGROUND: Tumors are usually considered to be clonal progeny of single transformed cells. Carcinosarcomas and malignant mixed epithelial tumors are examples where controversies exist regarding the singularity or multiplicity of their cell of origin. METHODS: The authors examined the clonality of carcinosarcomas (7 cases) and malignant mixed epithelial tumor (5 cases) in female patients by X-chromosome inactivation as a marker. Each component of the tumors were picked up by the laser capture microscope. The polymorphic exon 1 CAG trinucleotide repeat in the X-linked human androgen receptor (HUMARA) gene was amplified by a polymerase chain reaction before and after treatment of the methylation-sensitive endonuclease HpaII. RESULTS: Eleven cases were informative for clonality determination. Six out of seven carcinosarcomas and three out of four malignant mixed epithelial tumors revealed the same patterns of X-chromosome inactivation, which suggests that they are monoclonal. In contrast, the patterns of X-chromosome inactivation were different between the two tumor components in each cases of carcinosarcoma and malignant mixed epithelial tumor, indicating that they are of polyclonal origin. CONCLUSIONS: These observations show that although most of carcinosarcomas and malignant mixed epithelial tumors are of monoclonal origin, some of them are of polyclonal origin. This finding suggests that these tumors are genuinely polyclonal, and that they originated in the neoplastic transformation of more than one somatic cells

Clonality of multiple uterine leiomyomas / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clonality of uterine leiomyomas, especially the relationship between different nodules in multinodular cases.</p><p><b>METHODS</b>Genomic DNA was extracted from fresh tissue samples and digested through incubation with Hpa II and amplified through nested polymerase chain reaction for phosphoglycerate kinase (PGK) gene. The products were treated with Bst XI and resolved on agarose gels.</p><p><b>RESULTS</b>Among the 103 cases examined, 32 (31%) carried the polymorphic Bst XI site at the PGK locus. Eighty-nine tumors from the 29 cases were subjected to the cloning assay. Loss of polymorphism at the PGK locus was found in all tumor nodules, indicating the monoclonality of the tumor. The relationship between multiple tumors was also assessed by comparing their inactivated alleles. Seven nodules from a leiomyosarcoma were found to have originated from a single cell. However, the relationship was found to be more complicated, as demonstrated in 15 cases of multiple leiomyomas. The same inactivated allele was found in all nodules of 8 cases and in most nodules in 2 cases, while totally different inactivation patterns were observed in 5 cases. The difference was not associated with cell proliferation.</p><p><b>CONCLUSIONS</b>Clonality analysis can be applied to define the clonality of focal or nodular lesions. Uterine leiomyomas are of clonal origin. Multiple uterine leiomyomas may be subtyped into fully independent and aggressive types as well as a mixed type of both.</p>