Immunohistochemical evidence of progestin target cells in the pituitary gland of ovariectomized rat

Progestin (P) target cells were identified in the pituitary gland of gonadectomized female rats which had been primed with estrogen (E). P staining was localized using the immunohistochemical avidin-biotin-peroxidase (ABP) complex method. Dark brown precipitates were primarily found over the cytoplasm of cells in the pars distalis, but not in the pars intermedia nor in the pars nervosa. The majority of P-sensitive cells in the pars distalis were identical with luteotrophs, a few being lactotrophs. These observations suggest a role of P in the regulation of production and secretion of gonadotrophins in the pituitary glands of female rats.     

X-ray diffraction photographs of chicken gizzard G-actin.DNase I complex crystals taken with synchrotron radiation

X-ray diffraction photographs of a chicken gizzard G-actin.DNase I complex crystal have been recorded using the synchrotron radiation beam emitted by the Synchrotron Radiation Source at Daresbury and the Photon Factory at Tsukuba. The resolution limit was extended to 2.4 A and the exposure time was reduced approximately by a factor of 10, when data recorded at the Photon Factory, were compared with those recorded with a conventional rotating-anode source. Using a newly designed Weissenberg camera equipped with a multi-layer line screen, the diffraction data in a 36 degrees oscillation range were recorded on a single film up to 3.5 A resolution.     

Crystallization and preliminary crystallographic data of chicken gizzard G-actin . DNase I complex and Physarum G-actin . DNase I complex.

Smooth muscle G-actin from chicken gizzard and Physarum plasmodium G-actin both interact with DNase I and form 1 : 1 complexes. These complexes were crystallized by using polyethylene glycol 6000 as a precipitant. Both crystals belong to the same orthorhombic space group P2(1)2(1)2(1). The cell dimensions of chicken gizzard G-actin.DNase I complex are a=42.00 +/- 0.07 A, b=225.3 +/- 0.4 A, and c=77.4 +/- 0.1 A, while those of Physarum G-actin.DNase I complex are a=42 A, b=221 A, and c=77 A.     

Comparative embryogenesis of Mecoptera and Lepidoptera with special reference to the abdominal prolegs

The eruciform larvae of holometabolous insects are primarily characterized by bearing a varying number of abdominal prolegs in addition to three pairs of thoracic legs. However, whether the prolegs are evolutionarily homologous among different insect orders is still a disputable issue. We examined the embryonic features and histological structure of the prolegs of the scorpionfly Panorpa byersi Hua and Huang (Mecoptera: Panorpidae) and the Oriental armyworm Mythimna separata (Walker) (Lepidoptera: Noctuidae) to investigate whether the prolegs are homologous between these two holometabolous insect orders. In the scorpionfly, paired lateral process primordia arise on abdominal segments I–VIII (A1–A8) in line with the thoracic legs in early embryonic stages, but degenerate into triangular protuberances in later stages, and paired medial processes appear along the midventral line before dorsal closure and eventually develop into unjointed, cone‐shaped prolegs. Histological observation showed that the lumina of the prolegs are not continuous with the hemocoel, differing distinctly from that of the basic appendicular plan of thoracic legs. These results suggest that the prolegs are likely secondary outgrowths in Mecoptera. In the armyworm, lateral process primordia appear on A1–A10 in alignment with the thoracic legs in the early embryonic stages, although only the rudiments on A3–A6 and A10 develop into segmented prolegs with the lumina continuous with the hemocoel and others degenerate eventually, suggesting that the prolegs are true segmental appendages serially homologous with the thoracic legs in Lepidoptera. Therefore, we conclude that the larval prolegs are likely not evolutionarily homologous between Mecoptera and Lepidoptera. J. Morphol. 277:585–593, 2016. © 2016 Wiley Periodicals, Inc.     

β-structure from the microfibillar proteins of Merino wool

The β-structure of S-caboxymethyl derivatives of microfibrillar proteins isolated from Merino wool was investigated by X-ray diffraction for comparison with the structur of β-keratin. The S-carboxymethylated microfibrillar proteins(SCMKA) w well-oriented β-films of SCMKA weer obtained by stretching the SCMKA cast films in steam up to about 300% extesnsion. It was found that the reflections in β-pattern of SCMKA may be indexed on a pseudo-orthorhombic unit cell with a =0.94 nm, b = 0.66 nm and c = nm, where the ab, and c axes are in the direction of the interchain hydrogen bonding, the main chain(fibre axis) and the side chain, respectively. The unit cell dimesnions evaluated for SCMKA were almost the same as those for β-keratin, suggeting that few peptide sequences containing S-carboxymethyl cystine may be involved in the formation of β-structure from SCMKA.     

根霉超氧化物歧化酶同工酶类型的鉴别

利用ＫＣＮ、Ｈ_２Ｏ２和ＳＤＳ的选择性反应引起的ＳＯＤ同工酶谱带变化即可鉴别粗抽提液中的ＳＯＤ同工酶类型;用这种方法对五株不同种根霉的鉴别实验表明,它们均不同程度地含有Ｃｕ,Ｚｎ型和Ｍｎ型两种ＳＯＤ,前者约占８０％左右,后者只占２０％左右。用邻苯三酚自氧化法对样品中ＳＯＤ活性测定结果与在同工酶谱上的鉴别结果基本一致。     

Dynamics of hepatitis B virus quasispecies in association with nucleos(t)ide analogue treatment determined by ultra-deep sequencing

Background and Aims

Although the advent of ultra-deep sequencing technology allows for the analysis of heretofore-undetectable minor viral mutants, a limited amount of information is currently available regarding the clinical implications of hepatitis B virus (HBV) genomic heterogeneity.

Methods

To characterize the HBV genetic heterogeneity in association with anti-viral therapy, we performed ultra-deep sequencing of full-genome HBV in the liver and serum of 19 patients with chronic viral infection, including 14 therapy-naïve and 5 nucleos(t)ide analogue(NA)-treated cases.

Results

Most genomic changes observed in viral variants were single base substitutions and were widely distributed throughout the HBV genome. Four of eight (50%) chronic therapy-naïve HBeAg-negative patients showed a relatively low prevalence of the G1896A pre-core (pre-C) mutant in the liver tissues, suggesting that other mutations were involved in their HBeAg seroconversion. Interestingly, liver tissues in 4 of 5 (80%) of the chronic NA-treated anti-HBe-positive cases had extremely low levels of the G1896A pre-C mutant (0.0%, 0.0%, 0.1%, and 1.1%), suggesting the high sensitivity of the G1896A pre-C mutant to NA. Moreover, various abundances of clones resistant to NA were common in both the liver and serum of treatment-naïve patients, and the proportion of M204VI mutants resistant to lamivudine and entecavir expanded in response to entecavir treatment in the serum of 35.7% (5/14) of patients, suggesting the putative risk of developing drug resistance to NA.

Conclusion

Our findings illustrate the strong advantage of deep sequencing on viral genome as a tool for dissecting the pathophysiology of HBV infection.     

Karyotyping of comparative genomic hybridization human metaphases by using support vector machines.

BACKGROUND: Comparative genomic hybridization (CGH) is a relatively new molecular cytogenetic method for detecting chromosomal imbalance. Karyotyping of human metaphases is an important step to assign each chromosome to one of 23 or 24 classes (22 autosomes and two sex chromosomes). Automatic karyotyping in CGH analysis is needed. However, conventional karyotyping approaches based on DAPI images require complex image enhancement procedures. METHODS: This paper proposes a simple feature extraction method, one that generates density profiles from original true color CGH images and uses normalized profiles as feature vectors without quantization. A classifier is developed by using support vector machine (SVM). It has good generalization ability and needs only limited training samples. RESULTS: Experiment results show that the feature extraction method of using color information in CGH images can improve greatly the classification success rate. The SVM classifier is able to acquire knowledge about human chromosomes from relatively few samples and has good generalization ability. A success rate of moe than 90% has been achieved and the time for training and testing is very short. CONCLUSIONS: The feature extraction method proposed here and the SVM-based classifier offer a promising computerized intelligent system for automatic karyotyping of CGH human chromosomes.     

Dynamic reprogramming of histone acetylation and methylation in the first cell cycle of cloned mouse embryos

Epigenetic reprogramming is thought to play an important role in the development of cloned embryos reconstructed by somatic cell nuclear transfer (SCNT). In the present study, dynamic reprogramming of histone acetylation and methylation modifications was investigated in the first cell cycle of cloned embryos. Our results demonstrated that part of somatic inherited lysine acetylation on core histones (H3K9, H3K14, H4K16) could be quickly deacetylated following SCNT, and reacetylation occurred following activation treatment. However, acetylation marks of the other lysine residues on core histones (H4K8, H4K12) persisted in the genome of cloned embryos with only mild deacetylation occurring in the process of SCNT and activation treatment. The somatic cloned embryos established histone acetylation modifications resembling those in normal embryos produced by intracytoplasmic sperm injection through these two different programs. Moreover, treatment of cloned embryos with a histone deacetylase inhibitor, Trichostatin A (TSA), improved the histone acetylation in a manner similar to that in normal embryos, and the improved histone acetylation in cloned embryos treated with TSA might contribute to improved development of TSA-treated clones. In contrast to the asymmetric histone H3K9 tri- and dimethylation present in the parental genomes of fertilized embryos, the tri- and dimethylations of H3K9 were gradually demethylated in the cloned embryos, and this histone H3K9 demethylation may be crucial for gene activation of cloned embryos. Together, our results indicate that dynamic reprogramming of histone acetylation and methylation modifications in cloned embryos is developmentally regulated.