Preimplantation Genetic Diagnosis of X-linked Severe Combined Immunodeficiency / 中山大学学报(医学科学版)

[Objective]To establish a reliable and accurate preimplantation genetic diagnosis (PGD)method using multiple dis?placement amplification (MDA), which can be applied to the diagnosis of X-linked severe combined immunodeficiency disease (X-SCID).[Methods]Haplotype analysis for the X-SCID family was performedusing five short tandem repeats (STR) markers flanking the both sides of the interleukin-2 (IL-2) receptor gamma chain (IL2RG) gene. MDA technique was used for single-cell whole genomic amplification. The products were used as template in polymerase chain reaction (PCR) of informative STR markers found by linkage analysis for haplotype analysis as well as sequencing of the IL2RG gene exon 5.The amelogenin (AMEL) locus was used to do sex diag?nosis.[Results]Linked analysis revealed 3 STR markers were informative. The method was evaluated with 10 single lymphocytes and 10 single blastomeres. MDA was successful in all single cell. The detection efficiency of gene sequencing of pathogenic IL 2RG exon5 was 100%. The PCR efficiency of 3 STR informative markers and AMEL was 96.3%(77/80)and the average allele drop-out (ADO) rate was 11.5%(7/61). A cycle of PGD was performed on the family, and seven embryos were diagnosed, two of which were normal embry?os. Twin pregnancy occurred after transplantation which were given a healthy baby boy and a healthy baby girl.[Conclusion]In this study, multiple displacement amplification combined with specific amplification/sequencing of pathogenic gene and haplotype analysis in the single cell level of X-linked severe combined immunodeficiency disease were performed. The protocol can avoid misdiagnosis caused by contamination and ADO, and improve the diagnostic efficiency of PGD.

Determination of histatins 5 in salivary by reversed-phase high performance liquid chromatography method with ultraviolet detection / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The determination method of histatins 5 in human saliva with reversed-phase high performance liquid chromatography (HPLC) was developed.</p><p><b>METHODS</b>Salivary samples were collected and diluted with phosphate buffer (pH 2.5). The upper solution was determined with HPLC. Phosphate buffer (pH 3.5) of the mobile phase and C18 column was used throughout the experiment. The detection wavelength was 276 nm.</p><p><b>RESULTS</b>The linear ranges were 1.0-50.0 microg x mL(-1). The detection limit was 0.12 microg x mL(-1). The relative standard derivations (RSD) of standard solution for reserved time and peak area were 0.68% and 4.13% respectively. The proposed method was applied for analysis of salivary samples and the satisfactory results were obtained. RSD for sample determination was 4.41% and the average recoveries were 88.4%-109.0%.</p><p><b>CONCLUSION</b>The method was quick, simple and accurate. Analytical time was less than 15 min. It was adapted for analysis of salivary histatins 5 in salivary samples.</p>

Determination of organic acids in dental plaque with high performance liquid chromatography / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To establish determination method of formic acid, lactic acid, acetic acid and succinic acid in dental plaque with high performance liquid chromatography (HPLC).</p><p><b>METHODS</b>After the samples were centrifuged, 2 microL supernatant was transferred to a 1 mL centrifuge tube and diluted in water, then was determined with HPLC. The mixture of phosphate buffer and methanol (97:3) as mobile phase throughout the experiment. The determination of organic acid was performed on Phenomenex C18 column and at their maximum absorption wave.</p><p><b>RESULTS</b>The linear ranges of formic acid, lactic acid, acetic acid and succinic acid were 0.110-500, 0.049-500, 0.047-500, 0.084-500 microg/mL. The detection limits were 0.110, 0.049, 0.047, 0.084 microg/mL. The relative standard derivation were 9.5%, 7.9%, 4.3%, 4.2%. The average recoveries of samples were 82%-112%, 82%-102.5%, 90%-115%, 80%-110%.</p><p><b>CONCLUSION</b>The method was simple, quick and adapt for analysis of organic acid in dental plaque.</p>

Study on the relationship between organochlorine pesticides and level of residues in serum and daily foodstuff / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the contents of organochlorine pesticides in human bodies and residues in serum of populations with non-occupational exposure as well as to study the relationship between organochlorine pesticides in foodstuff and residues levels in serum.</p><p><b>METHODS</b>A cross-section study was conducted. 107 men and 142 women who were all healthy and living in the communities were investigated from Mar. 2004 to Jul. 2004. Level of daily food exposure was estimated through questionnaires while DDTs and HCHs serum levels were detected by EC-ECD. The relationship between organochlorine pesticides contents in foods and residues in serum were analyzed by ridge regression.</p><p><b>RESULTS</b>Fresh fish was positively correlated to men's serum level of beta-HCH and p,p'-DDT (beta = 0.1266 and beta = 0.0595) while vegetables and fruits were negatively correlated to women's serum level of beta-HCH (beta = -0.1066). Soybean was negatively correlated to women's serum level of p,p'-DDE and p,p'-DDT (beta = -0.0965 and 3 = -0.0581). Alcohol consumption was negatively correlated to men's serum level of beta-HCH and p,p'-DDE and women's serum level of p,p'-DDE (beta = -0.1315, beta = -0.1599 and P = -0.1128).Salted meat was negatively correlated to men's serum level of beta-HCH and p, p'-DDT (P = -0. 066 and P = - 0.0569).</p><p><b>CONCLUSION</b>In this study, fresh fish might increase the body burden of organochlorine pesticides and residues while alcohol might promote the excretion of organochlorine pesticides. Pickled meat and vegetal foodstuff might contain low-level of organochlorine pesticides and residues.</p>

Study on serum organochlorines pesticides (DDTs) level, CYP1A1 genetic polymorphism and risk of breast cancer: a case control study / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the potential effect of gene-environment interaction between CYP1A1 and serum dichlorodiphenyldichloroethane (DDT) levels on the risk of breast cancer in women, in China.</p><p><b>METHODS</b>A case-control study was conducted. From Dec. 2003 to Sep. 2004, 104 women with histologically confirmed breast cancers and 154 noncancerous controls from a community were enrolled in this study. Risk factors information of breast cancer was investigated by a questionnaire. Serum p, p'-dichlorodiphenyldichloroethane (p, p'-DDT) and 1, 1-dichloro-2, 2-bis (p-chlorophenyl) ethylene (p, p'-DDE) levels were tested by GC-ECD. CYP1A1 m2 gene type was tested by allele special-PCR method.</p><p><b>RESULTS</b>Serum DDT levels of case and control were (36.90 +/- 79.41) ng/ml and (50.60 +/- 150.70) ng/ml respectively. Serum 1, 1-dichloro-2, 2-bis (p-chlorophenyl) ethylene (p, p'-DDE) levels of case and control were (7.43 +/- 11.10) ng/ml and (8.96 +/- 11.30) ng/ml respectively. No statistically significant differences were found between the two groups with geometric mean t-test (P > 0.05). Compared with women who had homozygous wild-type CYP1A1 m2 genotype, significantly increased risks of breast cancer were found for women with the CYP1A1 m2 homozygous variant genotype [odds ratio (OR) = 2.61, 95% confidence interval (CI): 1.00 - 6.80]. Among premenopausal women, compared with women with homozygous wild-type of CYP1A1 genotype (Ile/Ile) and low serum DDT level (DDT serum level < or = 42.93 ng/ml), women with at least one variant allele of CYP1A1 m2 genotype and high serum DDT level (DDT serum level > or = 42.93 ng/ml) had higher risk of breast cancer (OR = 4.35, 95% CI: 1.140 - 16.950).</p><p><b>CONCLUSIONS</b>CYP1A1 m2 genetic polymorphism was associated with increased risk of female breast cancer while DDT exposure might have increased the risk of breast cancer among premenopausal women with CYP1A1 m2 variant genotype.</p>

Induced Mutagenesis of High Lipase Productivity Strain and Immobilization of Produced Lipase / 中国生物工程杂志

A mutant strain RZ13 with high lipase productivity was obtained through treating the Rhizopus sp. RXF12 by UV and microwave,and its activity was 2.62-fold of the original one. The high lipase productivity of the mutant strain could be inherited after repetitious subcultures.The optimal culture conditions of the RZ13 for producing lipase were studied.The lipase with highest activity (67.32U/ml) was obtained on the conditions of 25℃,pH 8.0,5 %(v/v) single spore suspension (1?107spore/ml) and 120 r/min for 84h,and stable under 40℃ and pH 8.5. In addition,the lipase was immobilized by adsorption onto Mg-Al hydrotalcite at 25℃ for 4 h by screening carriers and optimizing the immobilization. The results showed that the optimal reaction temperature and pH were 35~55℃ and 7.5~9.0,respectively,much wider than the free lipase.