Mutants of a highly pathogenic, porcine reproductive, and respiratory syndrome virus (PRRSV), JXA1 strain, were prepared by continuous in vitro passage. Genomic sequence comparisons were made between mutants obtained at different passages and the parental strain JXA1. The mutant strain obtained at passage 80 contained a 12 nucleotide insertion and 108 nucleotide mutations that resulted in 45 amino acid changes. Most of these changes (89%) occurred between passage 10 and 45 and were genetically stable for the next 35-70 passages. A comparison of the mutants, their parental strain, and several American PRRSV strains, identified 13 characteristic amino acid changes. These sites, as well as the distinct 12 nucleotide insertion, represent possible genetic markers for the evaluation of live vaccine applications, particularly for additional studies of the safety and potency of live PRRSV vaccines.

These experiments demonstrate that AGEs, independent of other metabolic factors, can induce vascular change resembling that of diabetic retinopathy.

N-myc Downstream-Regulated Gene 1 (NDRG1) is known as a differentiation-related gene that plays important roles in cell differentiation, organ formation, and embryonic development. NDRG1 has recently been shown to be associated with carcinogenesis and tumor progression in a wide variety of tumors. Phosphatase and tensin homolog deleted from chromosome (PTEN), a phosphatase and tensin homolog located on chromosome 10, is shown to be a tumor suppressor and is often mutated or deleted in various tumor cells, particularly in endometrial carcinoma. Using an immunohistochemical approach, we investigated the expression of NDRG1 and PTEN in normal endometrium, atypical hyperplasia, and endometrial carcinoma. All tumor tissues harvested in this study were derived from endometrioid carcinoma Type I, that were estrogenrelated. Our results demonstrate that the expression of NDRG1 was up-regulated in 5/40 (12.5%), 18/34 (52.94%), and 86/103 (83.5%) normal endometrium, atypical hyperplasia, and endometrial carcinoma cases, respectively (P < 0. The inactivation and mutation of tumor suppressor genes and the abnormal activation of proto-oncogenes may play important roles in the carcinogenesis and progression of endometrial carcinoma. N-myc Downstream-Regulated Gene 1 (NDRG1) has been mapped to human chromosome 8q24.2 with a 60 kb sequence and consists of 16 exons and 15 introns. It is present in all cells of the human body and is considered to encode a protein with a general, housekeeping function related to growth arrest, cell differentiation, organ formation, embryonic development, and maintaining the differentiating status. The expression of NDRG1 is regulated by several factors, including androgen, p53, and N-myc. Hypoxic conditions also induce NDRG1 expression via a mechanism that most likely involves nickel that interacts with the oxygen sensory pathway.(3) Pathologically, the expression of NDRG1 was previously shown to be up-regulated by the induction of differentiation in a colon carcinoma cell line.(4) More recently, NDRG1 has been associated with the progression of various human cancers, including colorectal carcinogenesis, (5) but it also seems to play an important role in the endometrial transformations leading to the completion of each menstrual cycle in humans.(6-8) It remains, however, controversial whether its overexpression suppresses or promotes tumor metastasis. (5,9,10) The phosphatase and tensin homolog deleted from chromosome10 (PTEN) gene was originally identified as a candidate tumor suppressor gene, located on chromosome 10q23.3. The PTEN gene encodes a phosphatase that dephosphorylates phosphatidylinositol-3,4,5-triphosphate.(11) It is known to play a key role in controlling cell growth, differentiation, and apoptosis.(12) Recently, the PTEN gene has been shown to be mutated or deleted in various human cancer cells.(13) The latter include prostate, breast, lung, glioblastoma, melanoma, and especially endometrial carcinoma, where deletion of PTEN was observed in more than 90% of the cases. (14,15) PTEN ...

The emergence and widespread of porcine circovirus-associated diseases (PCVADs), mainly caused by porcine circovirus type 2 (PCV2), threatens the Chinese swine industry. In this study, to investigate the recent prevalence of PCV2 in northern Guangdong Province of China, 573 tissue samples from 132 pig farms were collected during 2016–2021 and analyzed via PCR. Overall, 51.38% (297/573, 95%CI 47.74–55.92) samples were tested PCV2 positive. The detection rate of PCV2 was significantly lower in samples collected before 2016-2018 than after the outbreak of African Swine Fever (2019-2021), being 59.85% (158/264, 95%CI 53.94–65.76) and 41.47% (141/340, 95%CI 36.43–46.71), respectively. On the other end, the genetic characteristics of 26 PCV2 strains were further analyzed. These PCV2 strains belonged to three genotypes, including PCV2a, PCV2b, and PCV2d. Specifically, the predominant genotype prevalent during two periods (2016–2018 and 2019–2021) wasPCV2b (81.82%, 9/11) and PCV2d (80.0%, 12/15), respectively. The results above illustrated the high prevalence and the genetic evolution feature of PCV2 in Guangdong Province in recent years.

China is the largest producer of pearls, accounted for over 90% of world’s total pearl production. The triangle sail mussel (Hyriopsis cumingii), the most important species for freshwater pearl culture in China, is a well-known mussel recognized for pearl production with high yield and quality. Here, we reported a high-quality chromosome-level genome assembly of H. cumingii. The size of assembled genome was as large as 3.38 Gb with a scaffold N50 length of 3.19 Mb, and 2.04 Gb genome sequences were anchored onto 19 linkage groups. A total of 37,681 protein-coding genes and 50.86% of repeat elements were predicted and annotated. The expansive of 752 gene families compared to the most closely related Dreissena rostriformis, with a divergence time of 18.5 million years, might reveal an extensive set of genes associated to biomineralization, of which 237 genes were under strong positive selection in H. cumingii genome. Notably, the fibrillin gene family exhibited expansion and positive selection simultaneously, and multiple high expression after mantle implantation, suggesting the reason for outstanding biomineralization ability of H. cumingii. Furthermore, one fibrillin gene was confirmed as involving in deposition of calcium carbonate and formation of amorphous crystal during initial biomineralization based on RNA silencing and In vitro carbonate calcium crystallization assay. Fibrillin genes also diverse our attention from calcium deposition guided by matrix protein to interlamellar membrane configuration for understanding pearl formation. These findings provide a valuable genomic resource for carbonate biomineralization studies and fill the gap on freshwater mussel genome for evolutionary studies.