Attachment and multiplication,morphology and protein production of human fetal primary liver cells cultured in hormonally defined media

In Vitro Cellular &; Developmental Biology - Plant -     

Modes of DAPI banding and simultaneous in situ hybridization

By controlling the degree of chromatin denaturation through formamide incubation, or by heat treatment and/or by high pH, three types of high quality 4,6-diamidino-2-phenylindole (DAPI) bands can be produced sequentially on the same set of 5-bromo-2-deoxyuridine (BrdU)-incorporated chromosomes: first DAPI multibanding (the equivalent of Q-banding), then partial C-banding including distamycin A (DA)/DAPI banding, and finally C-banding pattern. It is assumed that the different DAPI-chromatin interactions following these treatments reflect the different chromatin structures at the chromosomal sites. Since the DAPI banding protocol is compatible with in situ hybridization, the combination of fluorescent in situ hybridization (FISH) with DAPI banding allows the simultaneous detection of signals from the DNA probes and the identification of the chromosomal band location of the probe. We demonstrate this useful application with the localization of the cystic fibrosis and Duchenne muscular dystrophy gene probes to their appropriate bands.     

Methodology in the study of seabass (Lates calcarifer Bloch): nutritional requirements in Singapore

This paper describes the effort of the Marine Aquaculture Section of the Primary Production Department in Singapore and the Institut Francais de Recherche pour l'Exploitation de la Mer in developing adequate facilities for fish nutritional requirement studies in Singapore, and in introducing appropriate nutritional methodology so that results are reliable and accurate. One of the first achievements was the demonstration of homogeneous fish (tropical seabass, Lates calcarifer Bloch) growth response in a newly established tank system before any nutritional experiments were initiated. The application of statistical procedures that take into consideration the power of a test and number of replications required has allowed for more accurate interpretation of results. This can be seen in the results of the first nutritional requirement experiment on the optimal dietary protein level of the seabass at constant energy.     

Equine follicle-stimulating hormone. Purification, acid dissociation, and binding to equine testicular tissue

A simple method of purification of equine follicle-stimulating hormone is described by which two forms of the hormone are obtained. The acid dissociation of the most active preparation was studied and a pKa of 5.8 was determined at 37 degrees C. This value is 2 pH units higher than that observed for pregnant mare serum gonadotropin suggesting that the binding areas between subunits are not identical in the two hormones. We also describe an homologous radioreceptor assay of equine follicle-stimulating hormone which is highly specific for this hormone in contrast to the heterologous systems described so far. The analysis of the properties of equine gonadotropins in homologous and heterologous radioreceptor assays suggests that all glycoprotein hormones share a common high affinity binding site and that specificity of binding is due to binding prohibition sites preventing fixation of each hormone to the receptors of the other glycoprotein hormones. This specific hindering is defined as "negative specificity."     

DNASE1L3 inhibits proliferation,invasion and metastasis of hepatocellular carcinoma by interacting with β‐catenin to promote its ubiquitin degradation pathway

As a member of the deoxyribonuclease 1 family, DNASE1L3 plays a significant role both inside and outside the cell. However, the role of DNASE1L3 in hepatocellular carcinoma (HCC) and its molecular basis remains to be further investigated. In this study, we report that DNASE1L3 is downregulated in clinical HCC samples and evaluate the relationship between its expression and HCC clinical features. In vivo and in vitro experiments showed that DNASE1L3 negatively regulates the proliferation, invasion and metastasis of HCC cells. Mechanistic studies showed that DNASE1L3 recruits components of the cytoplasmic β‐catenin destruction complex (GSK‐3β and Axin), promotes the ubiquitination degradation of β‐catenin, and inhibits its nuclear transfer, thus, decreasing c‐Myc, P21 and P27 level. Ultimately, cell cycle and EMT signals are restrained. In general, this study provides new insight into the mechanism for HCC and suggests that DNASE1L3 can become a considerable target for HCC.

Decreased expression of DNASE1L3 is associated with poor prognosis in patients with HCC DNASE1L3 inhibits the proliferation and cell cycle of HCC cells in vitro and promotes the invasion and metastasis of HCC cells DNASE1L3 inhibits the tumorigenicity and metastasis of HCC cells in vivo DNASE1L3 interacts with β‐catenin and promotes its binding to the β‐catenin destroying complex DNASE1L3 interacts with P21 and stabilizes P21 by mediating the deubiquitin activity     

Development of a fluorescent probe hydrolysis-insulated isothermal PCR for rapid and sensitive on-site detection of African swine fever virus

Highlights
1. A probe-based insulated isothermal PCR (iiPCR) assay was developed for rapid and onsite detection of ASFV.
2. The developed iiPCR showed similar sensitivity and specificity with OIE recommended real-time PCR.
3. Blood samples could be directly applied as PCR template in iiPCR without DNA extraction.     

Determination of cefazedone in human plasma by high performance liquid chromatography–tandem mass spectrometry: Application to a pharmacokinetic study on Chinese volunteers

A rapid, sensitive and simple high performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) method was developed for determination of cefazedone in human plasma using metronidazole as internal standard (IS). The chromatographic separation was achieved on an Ultimate XB-CN column (2.1 mm × 150 mm, 5 μm) with an isocratic mobile phase of acetonitrile and 20 mM ammonium acetate in 0.1% formic acid in water (15:85, v/v). Detection was performed using electrospray ionization in positive ion multiple reaction-monitoring mode (SRM), monitoring the transitions m/z 548.2 → 344.1 for cefazedone and m/z 172.2 → 128.1 for IS. Calibration curves were linear over a wide range of 0.20–401.12 μg/mL for cefazedone in plasma. The lower limit of quantification (LLOQ) was 0.20 μg/mL. The intra- and inter-day precisions were less than 7.2%. The average recovery of cefazedone was 90.8–91.0%. The validated method was successfully applied to the pharmacokinetic study of cefazedone in Chinese healthy volunteers following intravenous (IV) administration of 500, 1000 and 2000 mg cefazedone injection.     

Crystal structure of type VI effector Tse1 from Pseudomonas aeruginosa

The type VI secretion systems (T6SS) have emerging roles in interspecies competition. In order to have an advantage in defense against other organisms, this system in Pseudomonas aeruginosa delivers a peptidoglycan amidase (Tse1) to the periplasmic space of a competitor. An immune protein (Tsi1) is also produced by the bacterium to protect itself from damage caused by Tse1. Tsi1 directly interacts with Tse1. We report that the crystal structure of Tse1 displays a common CHAP protein fold. Strikingly, our structures showed that the third residue in the catalytic triad may be novel as this residue type has not been observed previously.