[Pilot study of genetic counseling and prenatal diagnosis in androgen insensitivity syndrome: with 3 families reports].

Objective: To explore genetic counseling and prenatal diagnosis strategies for women who have androgen insensitivity syndrome (AIS) family history or pregnancy history of AIS proband. Methods: Three families of complete AIS (CAIS) were retrospectively reported and summarized. The subsequent pregnancies and processes of prenatal diagnosis were followed up. Results: Among three CAIS families, one family had androgen receptors (AR) gene mutation diagnosis; the other two families were diagnosed clinically without gene diagnosis. All three mothers of CAIS probands were in pregnant again when they sought counseling, with gestational weeks between 7－13 weeks. They underwent chorionic villi sampling or amniocentesis in their second trimester (at 12, 16, 17 weeks respectively). Chromosome gender of all three fetuses were 46,XY, which was inconsistent with the ultrasonographic phenotype of external genitalia. All patients chose selective abortion in their second trimester. The external genitalia of all aborted fetuses were female phenotype, which supported the diagnosis of CAIS. Conclusion: Genetic counseling and prenatal diagnosis should be provided to high-risk patients with family history of AIS or proband pregnancy history, so as to achieve the goal of good childbearing and sound childrearing.

[Analysis of large deletion of phenylalanine hydroxylase gene in Chinese patients with phenylketonuria].

OBJECTIVE: To analyze the types and distribution of large deletion of phenylalanine hydroxylase (PAH) gene in Chinese patients with phenylketonuria (PKU). METHODS: On the basis of 953 PKU patients from Peking Union Medical College and Gansu Province Medical Genetics Center, which were detected by directed sequencing of PAH gene between 2006 and 2014. Multiplex ligation-dependent probe amplification (MLPA) of PAH gene was performed in 43 patients with one or two unknown genotypes. And the deletion breakpoints were characterized by Gap PCR-sequencing. RESULTS: Twenty-four large deletion/duplication alleles were found in 22 patients, accounting for 51.1%(24/47)of the 47 unknown mutations of the 43 patients.There were 6 different large deletions, including Ex1del3758 (n=10), Ex4_5del (n=4), Ex4_7del (n=3), Ex1del5329ins56 (n=3), Ex3del6599ins8 (n=2), and Ex4del (n=1); and 1 duplication was found (Ex12dup, n=1). The most common large deletions in Chinese patients were Ex1del3758 (21.3%), Ex4_5del (8.5%), and Ex4_7del (6.4%). CONCLUSIONS: Large deletion mutations of PAH gene are present in Chinese PKU patients. It's important to detect the large del/dup mutation, and there are different hotspot mutation genotypes in Chinese patients.

Validation of quantitative fluorescent-PCR for rapid prenatal diagnosis of common aneuploidies in the Chinese population.

Quantitative fluorescent polymerase chain reaction (QF-PCR) is an accurate and reliable method for rapid detection of aneuploidy; however, it is not routinely used in China. We aimed to validate QF-PCR as a means for prenatal common aneuploidy screening and to analyze the heterozygosities of short tandem repeat (STR) markers in the Chinese population. The sequences of 19 STR markers in chromosomes 21, 18, 13, X, and Y were designed; three kinds of fluoresceins were used to label the primers, and the QF-PCR detecting conditions were explored and optimized. The results of analysis of 210 prenatal samples by multiplex QF-PCR were compared with karyotyping analysis. All cases were successfully tested by QF-PCR and conventional cytogenetic analysis. QF-PCR results were consistent with the results of cytogenetic analyses, with the exception of two cases. The sensitivity and specificity of QF-PCR to diagnose common aneuploidies were 94.74 and 100%, respectively. The heterozygosities of most of the markers were lower than reported for Western populations, but relatively similar to those of other Asian populations. We conclude that QF-PCR is able to detect the common aneuploidies for prenatal diagnosis with high detection efficacy; therefore it is suitable for rapid prenatal diagnosis and for large-scale testing in laboratories. However, we need to add new STR markers or to find alternative STR markers with high heterozygosity in order to make this technique useful for routine diagnosis.

Simulated geochemical weathering of a mineral ash-rich biochar in a modified Soxhlet reactor.

Although there are many studies on the characterization of C in biochar and its C sequestration potential, there is little knowledge on the mineral fraction in biochar and its weathering. The latter, however, can have powerful implications on nutrient availability. In the present study, a modified Soxhlet reactor was used to simulate the long-term geochemical weathering of an ash-rich biochar produced from sewage sludge of a non-industrial area in New Zealand. The weathering process took place during a period of 300 h, with and without the addition of humic acid (1.00 g added to 20.00 g of biochar), and the treatments were referred to as treatment BC-HA and BC-B, respectively. Both the leaching kinetics and the transformations within the solid phase were studied. The results revealed that substantial amounts of K (8.5-10.2%) and S (20.2-28.3%) were recovered in the weathering solutions. Noticeable Ca (17.9-20.7%) and P (15.4%) in the solid were released but only a few were recovered in the weathering solutions because of the precipitation. The presence of humic acids increased this dissolution and thus the availability of K, S, Ca, Mg and P, but induced N immobilization. Nitrogen availability was already very low (<1.0% of the total N) due to the probable recalcitrant heterocyclic N structure. The pH of the biochar samples dropped from 8.4 to 7.5; this was mainly attributed to loss of base cations through leaching and probable carbonation of the system. The XPS spectra evidenced the oxidation of C in biochar during the weathering process with the formation of carbonyl and carboxylic functional groups. The results obtained in this study showed some promise for the positive use of modified Soxhlet extractor in simulating the geochemical weathering in ash-rich biochars and providing a better understanding on the kinetics of nutrient release. This will be key information in assessing the added value of biochars as soil amendments.

Chemical changes in heavy metals in the leachates from Technosols.

A 2 month long column study was conducted to evaluate the mobility of heavy metals eluting from Technosols constituted from sewage sludges (aerobic or anaerobic) (as controls) or a mixture of different types of sewage sludges with green foundry sand (FS) or/and Linz-Donowitz slag (LD). The organic and inorganic wastes were mixed at a ratio of 56:44 (w/w). The mixtures and the controls were moistened to field capacity before adding them to the polypropylene columns (4.5 cm wide and 14 cm long). During the 8-week experimental period, the columns were watered, twice a week, with 100 mL of deionised water. The concentrations of heavy metals (Cu, Zn, Ni, Pb, Cd, and Cr) in the leachates were determined periodically. The concentrations of all the heavy metals were generally higher in the leachates from the Technosols containing anaerobic sewage sludge as a component. The concentration of Cu was strongly dependent on pH and was significantly higher (P<0.05) in the most alkaline leachates (pH>10) than in the other leachates. More Zn was mobilized in the most acidic leachates (pH<6) than in other leachates. The concentration of Ni in 80% of the leachates exceeded the EU drinking water limit for Ni (0.02 mgL(-1)). The concentrations of Pb were lower in the Technosols containing FS. The concentrations of Cd in the leachates from Technosols containing the conditioners were relatively high, while concentrations of Cr were higher in the controls. As far as the potential toxicity of heavy metals is concerned, the combination of aerobic sludge, inorganic conditioners able to buffer the pH to around neutrality, and reactive aluminosilicates, can be regarded as suitable choice for formulating Technosols from wastes.

Influence of the acid buffering capacity of different types of Technosols on the chemistry of their leachates.

The preparation of tailor-made Technosols from wastes may be a novel and prospective option for the re-use of wastes and restoration of degraded areas. A two-month study with pilot columns was conducted to evaluate the influence of the acid buffering capacity of different Technosols on the chemistry of their leachates. The Technosols were made from mixtures of organic and inorganic wastes at a ratio of 56:44 (w/w). The organic components used were an anaerobic (AN) and an aerobic (AE) sewage sludge. The inorganic wastes used--referred to as "conditioners"--were Linz-Donowitz slag (LD) and foundry sand (FS). A mixture of the two conditioners at a ratio of 50:50 (w/w) was made to provide a third type of conditioner (LD+FS). Controls consisted of columns filled with organic waste only (either AN or AE sludges). Changes in pH, electrical conductivity, concentrations of major ions and dissolved organic carbon in the leachates were evaluated periodically. The main processes determining the pH of the systems were nitrification and leaching, but organic matter decomposition and carbonation may also have had an influence. Nitrification was strongly retarded in the AN sludge (attributed to the probable absence of nitrifiers in this waste after the AN wastewater treatment) and was impeded in those mixtures in which LD was used as a component (due to the liming effect). Final pH values ranged from 5.0 and 5.4 (in AE and AE+FS, respectively) to 11.1 (in AN+LD). The pH of the other mixtures finally ranged between 7 and 8. In formulating mixtures of wastes, their acid buffering capacity should be taken into account in addition to the nutrient contents and the limits of contaminants established by local regulations.

Evaluation of accelerated dechlorination of p,p'-DDT in acidic paddy soil.

The reductive dechlorination and behavior of p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) was investigated in a paddy soil. Treatment with 5% (w/w) metallic iron (Fe(0)) resulted in sharp decrease of p,p'-DDT, whereas there was no extra effect when 2% (w/w) aluminum sulfate (Al(2)(SO(4))(3)) was added to the Fe(0) treatment. These results suggest that Fe(0) could effectively promote the reductive dechlorination of p,p'-DDT and its metabolites while Al(2)(SO(4))(3) did not show any effect on those processes. Furthermore, p,p'-DDT and its daughter compounds inhibited holistic soil respiration greatly at first but could be metabolized by certain species of indigenous microorganisms after a period of adaptation time in the soil. When treated with Fe(0), the polluted soil produced much less CO(2) while the addition of Al(2)(SO(4))(3) counteracted its negative effect to much extent.