Clinical and cytogenetic results of a series of amniocentesis cases from Northeast China: a report of 2500 cases

The aims of this study were to demonstrate the clinical and cytogenetic results of amniocentesis (AS) cases in Northeast China, to compare the incidence of different kinds of chromosomal abnormalities, and to study the association between the detection rate of chromosomal abnormalities and different indications for prenatal diagnosis. Cytogenetic analysis was performed on long-term tissue cultures of 2500 second-trimester amniotic fluid samples. The most common indication for genetic AS was abnormal maternal serum-screening test (69.56%), followed by advanced maternal age (15.04%). Chromosomal abnormality was detected in 206 (8.24%) of the 2500 samples. The detection rate of abnormal karyotypes was 62.5% in the group in which one member of the couple was a carrier of a chromosome abnormality; in the group having a positive result from noninvasive prenatal testing, the frequency was 50%. To determine the origin of fetal chromosome abnormal karyotype, 45 fetuses were analyzed. Of these, 20 were found to be de novo abnormalities and 25 were familial. The frequency and proportion of abnormal karyotypes varied substantially across different maternal AS indications. Knowing the origin and type of chromosomal abnormality would help determine termination or continuation of the pregnancy.

Varicocele and male infertility in Northeast China: Y chromosome microdeletion as an underlying cause

The prevalence of Y chromosome microdeletions among azoospermic, severe oligozoospermic, moderate oligozoospermic, and mild oligozoospermic patients with varicocele-related and idiopathic infertility shows conflicting data in Asian countries. We aimed to detect this frequency in Northeast China, and investigated spermatogenic defects whether associated with varicocele or Y chromosome microdeletions. All samples underwent a thorough physical examination, semen analysis, and PCR analyses for Y chromosome microdeletions. We randomly selected 150 infertile non-obstructive azoospermic patients with left varicocele (Group 1), 150 idiopathic non-obstructive azoospermic infertility patients (Group 2), 150 infertile severe oligozoospermic patients with left varicocele (Group 3), 150 idiopathic severe oligozoospermic infertility patients (Group 4), 150 infertile moderate oligozoospermic patients with left varicocele (Group 5), 150 idiopathic moderate oligozoospermic infertility patients (Group 6), 150 infertile mild oligozoospermic patients with left varicocele (Group 7), 150 idiopathic mild oligozoospermic infertility patients (Group 8), and 60 healthy unrelated men with proven fertility were recruited as control subjects (Group 9). We observed that our samples from Northeastern China had a higher frequency of microdeletions among the non-obstructive azoospermic individuals with varicocele, as compared with other Asian countries. Furthermore, the spermatogenic defect is due to the underlying Y chromosome microdeletion, and not the varicocele itself. Although varicocele is not the cause of male infertility, it may be associated with male infertility in the Northeastern Chinese population.

Two novel cytotoxic and antimicrobial triterpenoids from Pseudolarix kaempferi

Two novel antimicrobial and cytotoxic triterpenoids, isopseudolarifuroic acids A (1) and B (2), were isolated from the bark of Pseudolarix kaempferi. The structural elucidation of two novel compounds was carried out mainly by spectroscopic methods, and also by computer modeling. Compounds 1 and 2 exhibited significant cytotoxic activities against several tumor cell lines. Compound 1 also showed most potent antimicrobial activities against both Gram-positive and Gram-negative bacteria.

Novel ceramides from the fungus Lactarium volemus

Two novel ceramides, lactariamides A (N-2'-hydroxytetracosanoyl-2-amino-3,4-epoxyoctadecan-1-ol (1)) and B ((4E,8E)-N-2'-hydroxyoctadecanoyl-2-amino-9-methyl-4,8-octadecadine-1,3-diol (2)), were isolated from the fungus Lactarium volemus, together with a known compound, cerebroside D (3). Their structures were determined on the basis of chemical evidence and spectral methods.

Sterols from the fungus Lactarium volemus

Seven ergostane-type sterols and two mono-glucosides were isolated from the ethyl acetate soluble fraction of Lactarium rolemus. Three are previously unknown, i.e. 3-O-beta-D-glucopyranosyl-22E,24R-5alpha,8alpha-epidioxyergosta-6,22-diene, 3-O-beta-D-glucopyranosyl-22E,24R-5beta,8beta-epidioxyergosta-6,22-diene and 22E,24R-ergosta-7,22-diene-3beta,5alpha,6beta,9alpha-tetraol. The structural elucidation of these compounds was mainly achieved by spectroscopic methods.

[The development of mouse bioreactor expressing human tissue plasminogen activator (tPA) in mammary gland by transfecting spermatozoa in testicular duct]

The most established methods for development of transgenic animals are the microinjection of DNA into the fertilized eggs, but it is still a procedure of certain complexity and high cost. Therefore, the idea of using sperm as a vehicle to carry exogenous DNA into eggs is very attractive, and there have been some successful reports. Though the methods are rather simple they sometimes have low reproducibility. To improve the technique we transinfected the spermatozoa in testicular duct, not in vitro, to produce mice which expressed human tissue plasminogen activator (tPA) in mammary gland. The results demonstrated that: (1) 5 transinfected mice mated 10 female mice in 10 days after operation, (2) 79 founders were developed and 42 survived, (3) using PCR to detect foreign DNA integrated into the genome of founders, 7 out of 42 founders were positive (16.67%), (4) The expression level of tPA was 48-80 ng/ml in the milk of 5 PCR positive founders and (5) the foreign DNA integrated into the genome was detected in 2 out of 4 1st offspring by PCR technique.

Diterpenoids from isodon eriocalyx

Three new diterpenoids, eriocalyxins C-E (1-3), were isolated from Isodon eriocalyx. Their structures were elucidated as 6beta-hydroxy-15beta-acetoxy-3alpha,20-epoxy-16beta, 17-epoxy-ent-kaur-1,7-dione (1), 1alpha,7beta-dihydroxy-6beta, 15beta-diacetoxy-7,20-epoxy-ent-kaur-16-ene (2), and 15beta-acetoxy-1,6-dioxo-6,7-seco-ent-kaur-2,16-dien-7,20-olide (3), respectively, by means of spectroscopic methods, including one- and two-dimensional NMR techniques.

[Expression and regulation of milk protein gene in mammalia]

On the basis of introducing the structures and relations of evolution in milk protein genes, the factors involved in gene expression including cis-acting elements, trans-acting factors as well as induction of hormones were discussed. Finally the applicable prospect of mammary gland as a bioreactor was estimated.