Global fungal-host interactome mapping identifies host targets of candidalysin

Candidalysin, a cytolytic peptide toxin secreted by the human fungal pathogen Candida albicans, is critical for fungal pathogenesis. Yet, its intracellular targets have not been extensively mapped. Here, we performed a high-throughput enhanced yeast two-hybrid (HT-eY2H) screen to map the interactome of all eight Ece1 peptides with their direct human protein targets and identified a list of potential interacting proteins, some of which were shared between the peptides. CCNH, a regulatory subunit of the CDK-activating kinase (CAK) complex involved in DNA damage repair, was identified as one of the host targets of candidalysin. Mechanistic studies revealed that candidalysin triggers a significantly increased double-strand DNA breaks (DSBs), as evidenced by the formation of γ-H2AX foci and colocalization of CCNH and γ-H2AX. Importantly, candidalysin binds directly to CCNH to activate CAK to inhibit DNA damage repair pathway. Loss of CCNH alleviates DSBs formation under candidalysin treatment. Depletion of candidalysin-encoding gene fails to induce DSBs and stimulates CCNH upregulation in a murine model of oropharyngeal candidiasis. Collectively, our study reveals that a secreted fungal toxin acts to hijack the canonical DNA damage repair pathway by targeting CCNH and to promote fungal infection.

[Effects of cinepazide maleate injection on blood pressure in patients with acute ischemic stroke and hypertension]

Objective: To investigate the blood pressure change in patients with acute ischemic stroke (AIS) and hypertension treated with cinepazide maleate injection. Methods: This was a subgroup analysis of post-marketing clinical confirmation study of cinepazide maleate injection for acute ischemic stroke: a randomized, double-blinded, multicenter, placebo-parallel controlled trial, which conducted in China from August 2016 to February 2019. Eligible patients fulfilled the inclusive criteria of acute anterior circulation ischemic stroke with National Institutes of Health Stroke Scale (NIHSS) scores of 7-25. The primary endpoints were mean blood pressure of AIS patients treated with cinepazide maleate or control, which were assessed during the treatment period (14 days), and the proportion of the patients with normal blood pressure was analyzed after the treatment period. Furthermore, a subgroup analysis was performed to investigate a possible effect of the history of hypertension on outcomes. Results: This analysis included 809 patients with hypertension. There was no significant difference in patients blood pressure and the proportion of patients with normal blood pressure (60.5% vs. 59.0%,P>0.05) between cinepazide maleate group and control group. Conclusion: Administration of cinepazide maleate injection does not affect the management of clinical blood pressure in patients with AIS.

The presence of Prevotella melaninogenica within tissue and preliminary study on its role in the pathogenesis of oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) is a chronic inflammatory disease that occurs in the oral mucosa with characteristic white striations lesions, recurrent erosions, and pains. The etiology and pathogenesis of OLP are still unclear.

MATERIALS AND METHODS

We analyzed the bacterial community structure of buccal mucosa in patients with OLP and normal controls by high-throughput sequencing. Fluorescence in situ hybridization (FISH) was used to detect Prevotella melaninogenica (P. melaninogenica) in 13 OLP samples and 10 controls. The amounts of P. melaninogenica in OLP buccal mucosa and the expression of inflammatory cytokines in co-culture of mouse-derived macrophages with P. melaninogenica were detected by RT-qPCR.

RESULTS

The P. melaninogenica was more abundant in OLP than in healthy controls, and the differences were significant at the level of the phylum, family, genus, and species (p < .05). FISH showed that P. melaninogenica can invade the epithelium and even the lamina propria of OLP, while no invasion was found in the normal mucosa. Prevotella melaninogenica can adhere to and invade macrophages and then activate the transcription of IL-1β, IL-6, and TNF-α in NF-κB signaling pathway.

CONCLUSION

Prevotella melaninogenica may be involved in the pathogenic process of OLP, and its specific mechanism deserves further study.

HuoXue JieDu formula improves diabetic retinopathy in rats by regulating microRNAs

ETHNOPHARMACOLOGICAL RELEVANCE

HuoXue JieDu Formula (HXJDF) originates from classical formulas and was formed based on clinical experience. It is composed of Euonymus alatus (Thunb.) Siebold, Panax notoginseng (Burkill) F.H. Chen, the roots of Anguina kirilowii (Maxim.) Kuntze, and Coptis omeiensis (C. Chen) C.Y.Cheng. HXJDF prevents the deterioration of diabetic retinopathy.

AIM OF THE STUDY

To evaluate the effects of HXJDF on diabetic retinopathy in rats and investigate the roles of miRNAs in the effects of HXJDF.

MATERIALS AND METHODS

A single intraperitoneal injection of streptozotocin (STZ) (65 mg/kg) was used to induce diabetes in rats. Rats were divided into three groups: normal, diabetic, and diabetic + HXJDF. Rats were treated with HXJDF (15.4 g/kg) or water by oral gavage for twelve weeks. At the end of the treatment, rats were anaesthetized, and retinal haemodynamic changes were measured. Then, the retinas were removed and examined by haematoxylin and eosin (HE) staining and TUNEL assays. In addition, miRNA expression profiling was performed using miRNA microarrays and further validated by quantitative real-time PCR (qRT-PCR).

RESULTS

Diabetes reduced peak systolic velocity (PSV), end-diastolic velocity (EDV), mean velocity (MV) and central retinal vein velocity (CRV) but increased the resistance index (RI) and pulsatility index (PI). In addition, in the diabetic group, retinal cell arrangement was disordered and loosely arranged, the retinal thickness and retinal ganglion cell (RGC) number decreased, and retinal cell apoptosis increased. In addition, 11 miRNAs were upregulated and 4 miRNAs were downregulated. After treatment, HXJDF improved retinal haemodynamics and morphologic changes, restored retinal thickness and RGC number and decreased retinal cell apoptosis. Furthermore, the changes in miRNA expression were significantly abolished by HXJDF.

CONCLUSION

HXJDF may prevent DR by regulating the expression of miRNAs.

Gut microbiota contributes to the distinction between two traditional Chinese medicine syndromes of ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is considered to be closely associated with alteration of intestinal microorganisms. According to the traditional Chinese medicine (TCM) theory, UC can be divided into two disease syndromes called Pi-Xu-Shi-Yun (PXSY) and Da-Chang-Shi-Re (DCSR). The relationships among gut microbiota, TCM syndromes, and UC pathogenesis have not been well investigated.

AIM

To investigate the role of gut microbiota in UC and the distinction of microbiota dysbiosis between PXSY and DCSR syndromes.

METHODS

From May 2015 to February 2016, UC patients presenting to LongHua Hospital who met the established inclusion and exclusion criteria were enrolled in this retrospective study. Fresh stool specimens of UC patients with PXSY or DCSR were collected. The feces of the control group came from the health examination population of Longhua Hospital. The composition of gut bacterial communities in stool samples was determined by the pyrosequencing of 16S ribosomal RNA. The high-throughput sequencing reads were processed with QIIME, and biological functions were predicted using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States.

RESULTS

The composition of gut bacterial communities in 93 stool samples (30 healthy controls, 32 patients with PXSY syndrome, and 31 patients with DCSR syndrome) was determined by the pyrosequencing of 16S ribosomal RNA. Beta diversity showed that the composition of the microbiota was different among the three groups. At the family level, Porphyromonadaceae, Rikeneliaceae, and Lachnospiraceae significantly decreased while Enterococcus, Streptococcus, and other potential pathogens significantly increased in UC patients compared to healthy subjects. At the genus level, Parabacteroides, Dorea, and Ruminococcus decreased while Faeca-libacterium showed increased abundance in UC compared to healthy controls. Five differential taxa were identified between PXSY and DCSR syndromes. At the genus level, a significantly increased abundance of Streptococcus was observed in DCSR patients, while Lachnoclostridium increased in PXSY patients. The differential functional pathways of the gut microbiome between the PXSY and DCSR groups mainly included lipid metabolism, immunity, and the metabolism of polypeptides.

CONCLUSION

Our study suggests that the gut microbiota contributes to the distinction between the two TCM syndromes of UC.

Polymorphism and Forensic Application Value of 71 Y-SNP Loci in Han Population of Northwest China

OBJECTIVES

To analyze the polymorphism of 71 SNP loci on Y chromosome in Han population of Northwest China, to assess its forensic application value, and to screen out Y-SNP loci for forensic examination of Han population in East, South, and Northwest China based on the integration of previous research results.

METHODS

Multiplex polymerase chain reaction （PCR） and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS） were performed on 71 Y-SNP loci of 202 unrelated Han male individuals in Northwest China. Gene diversity （GD） and haplotype diversity （HD） values were calculated, and then Y-SNP loci of Han population in East, South, and Northwest China were screened with the combination of data from previous research.

RESULTS

Among the detected 71 loci, 67 loci were polymorphic in the Northwest Han male population, with GD values 0.010 0-0.502 2. There were 22 and 25 loci with a moderate （0.2≤GD<0.3） and high （GD≥0.3） amount of genetic information, respectively. There were 26 loci for the Han communities in Northwest, South, and East China.

CONCLUSIONS

Y-SNP loci are potential in paternity testing and individual identification, as well as the judgement of population distribution and migration.

[Assessment on Application of 24 Y-STR Loci in Forensic Science]

OBJECTIVES

To select a Y-STR marker system with strong haplotype identification ability, appropriate mutation rate and high compatibility and to assess its forensic application.

METHODS

The 24 Y-STR loci were tested by self-built fluorescent multiplex system, and the forensic assessment was conducted by 139 pairs of father-son samples collected in Jinan, Shandong province.

RESULTS

Totally 176 alleles were identified among the 24 Y-STR loci in the sample of 139 unrelated individuals labeled with father, and the gene diversity （GD） distributed between 0.083 7 （DYS645）-0.966 9 （DYS385a/b）. According to the 24 Y-STR loci, 139 different haplotypes were detected from 139 unrelated male individuals labeled with father in Han population of Shandong province and with no shared haplotype observed. The overall haplotype diversity （HD） was 1 and the discrimination capacity （DC） was 1. A total of 5 one-step mutations events were observed among the 24 Y-STR loci in 139 pairs of father-son. The average mutation rate was 0.001 5 [95% CI （0.000 5, 0.003 5）].

CONCLUSIONS

The system of 24 Y-STR loci shows a strong individual recognition ability and low mutation rate in the population in Jinan, Shandong province, and it has good application value in forensic science.

[Sixty-six Biallelic Genetic Markers on Y chromosome by MALDI-TOF-MS]

OBJECTIVES

To analyse the genetic polymorphisms of 66 biallelic genetic markers on Y chromosome in Eastern Chinese Han population, and evaluate their values in forensic application.

METHODS

Genotyping of 66 biallelic genetic markers on Y chromosome was studied in 205 unrelated males of Eastern Chinese Han population by multiplex PCR combined matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. The allele frequencies on the loci to be tested were calculated by direct counting method, and the gene diversity （GD） and haplotype diversity （HD） were calculated by corresponding formulas. The haplotypes of this system were tested by software Arlequin v3.5.2.2 and the comparison of population genetics were analyzed.

RESULTS

A total of 60 biallelic genetic markers on Y chromosome were polymorphic in males of Eastern Chinese Han population, and the ranges of GD were from 0.038 5 to 0.501 9. Eighty-five different haplotypes were observed and the HD was 0.970 3. The differences of partial SNP loci between the Han population of Eastern China and that of Xinjiang and Guangdong were statistically significance.

CONCLUSIONS

Sixty biallelic genetic markers and the detection system can complementally provide genetic information in kinship testing and individual identification. The MALDI-TOF-MS technology is able to type biallelic genetic markers.

[Forensic Investigation in Han Population by SiFa™ 23 Plex Kit （Beta Version）]

OBJECTIVES

To investigate the performance of SiFa™ 23 Plex Kit （beta version） and its population genetics of STR loci in Han population.

METHODS

Genotyping was performed for 1 000 unrelated healthy Han individuals by the kit. The efficiency of the kit was tested, and the frequency data and population genetics parameter information of STR loci were analysed statistically.

RESULTS

The minimum amplification system could be 6.25 μL. In 25 μL standard reaction system, a satisfied genotyping profiles could be obtained with the DNA content as low as 125 pg. Among the 1 000 individuals, 267 alleles were detected by 21 autosomal STR loci of the kit, which conformed to Hardy-Weinberg equilibrium. Fifteen and eleven alleles were observed at the newly added STR loci D1S1656 and D10S1248, respectively, which showed a high polymorphism information content.

CONCLUSIONS

SiFa™ 23 Plex Kit （beta version） is excellent in testing blood samples. Its accuracy, repeatability and sensitivity can satisfy the need of forensic practice, which makes it be applied to forensic-related case work and DNA database establishment.

Population Difference Analysis of Allele Frequencies of 24 Y-STR Loci

OBJECTIVES

To investigate the population genetic polymorphisms of 24 Y-STR loci in unrelated individuals in Eastern Chinese Han population, and to compare the difference of Han group between Eastern China and Guangdong.

METHODS

The population genetics of 24 Y-STR loci in 268 unrelated Han individuals from Eastern China were analyzed by GFS 24 Y-STR amplification kit. The allele frequencies in Eastern Chinese Han population were compared with the data in Guangdong Han population, and the difference analysis between two groups was performed.

RESULTS

Among the 24 Y-STR loci of 268 unrelated Han individuals from Eastern China, 235 alleles and 267 haplotypes were observed. GD value ranged from 0.564 9 to 0.966 8. The difference between 12 loci （DYS622, DYS552, DYS443, et al.） of Han population in Eastern China and in Guangdong was statistically significance.

CONCLUSIONS

GFS 24Y STR amplification system shows favorable polymorphisms, which can be used in patrilineal genetic relationship identification.

Early evidence of the genus Homo in East Asia

The timing and route of the earliest dispersal from Africa to Eastern Asia are contentious topics in the study of early human evolution because Asian hominin fossil sites with precise age constraints are very limited. Here we report new high-resolution magnetostratigraphic results that place stringent age controls on excavated hominin incisors and stone tools from the Yuanmou Basin, southwest China. The hominin-bearing layer resides in a reverse polarity magnetozone just above the upper boundary of the Olduvai subchron, yielding an estimated age of 1.7Ma. The finding represents the age of the earliest documented presence of Homo, with affinities to Homo erectus, in mainland East Asia. This age estimate is roughly the same as for H. erectus in island Southeast Asia and immediately prior to the oldest archaeological evidence in northeast Asia. Mammalian fauna and pollen obtained directly from the hominin site indicate that the Yuanmou hominins lived in a varied habitat of open vegetation with patches of bushland and forest on an alluvial fan close to a lake or swamp. The age and location are consistent with a rapid southern migration route of initial hominin populations into Eastern Asia.

Molecular dynamics simulation study for LRH-1: Interaction with fragments of SHP and function of phospholipid ligand

The liver receptor homolog-1 (LRH-1) is an important transcriptional factor in the process of cholesterol and bile acids metabolism. In this article, molecular dynamics simulation for six systems with total 60 ns is employed to study LRH-1. LRH-1/phospholipid and LRH-1/SHP (fragments) interactions are analyzed by counting atomic contact number, identifying hydrogen bonds, and estimating binding free energies (by MM-PB/SA and N-mode analysis). Through integrating our modeling result with previous experimental data, deeper understandings to LRH-1/SHP interaction are obtained, and functions of the phospholipid ligand in LRH-1 are proposed.

3D-QSAR studies with the aid of molecular docking for a series of non-steroidal FXR agonists

The farnesoid x receptor (FXR) has become a potential drug target for treating cholesterol-related and bile acid-related diseases recently. In this paper, 3-dimensional quantitative structure-activity (structure-affinity and structure-efficacy) relationships are investigated for a series of non-steroidal agonists (fexaramine series) by using the comparative molecular field analysis (CoMFA), where molecular docking method (FlexX) is employed to construct molecular superimposition maps. A proposal to design some new agonists is discussed lastly.

New evidence on the earliest human presence at high northern latitudes in northeast Asia

The timing of early human dispersal to Asia is a central issue in the study of human evolution. Excavations in predominantly lacustrine sediments at Majuangou, Nihewan basin, north China, uncovered four layers of indisputable hominin stone tools. Here we report magnetostratigraphic results that constrain the age of the four artefact layers to an interval of nearly 340,000 yr between the Olduvai subchron and the Cobb Mountain event. The lowest layer, about 1.66 million years old (Myr), provides the oldest record of stone-tool processing of animal tissues in east Asia. The highest layer, at about 1.32 Myr, correlates with the stone tool layer at Xiaochangliang, previously considered the oldest archaeological site in this region. The findings at Majuangou indicate that the oldest known human presence in northeast Asia at 40 degrees N is only slightly younger than that in western Asia. This result implies that a long yet rapid migration from Africa, possibly initiated during a phase of warm climate, enabled early human populations to inhabit northern latitudes of east Asia over a prolonged period.

Onset of Asian desertification by 22 Myr ago inferred from loess deposits in China

The initial desertification in the Asian interior is thought to be one of the most prominent climate changes in the Northern Hemisphere during the Cenozoic era. But the dating of this transition is uncertain, partly because desert sediments are usually scattered, discontinuous and difficult to date. Here we report nearly continuous aeolian deposits covering the interval from 22 to 6.2 million years ago, on the basis of palaeomagnetic measurements and fossil evidence. A total of 231 visually definable aeolian layers occur as brownish loesses interbedded with reddish soils. This new evidence indicates that large source areas of aeolian dust and energetic winter monsoon winds to transport the material must have existed in the interior of Asia by the early Miocene epoch, at least 14 million years earlier than previously thought. Regional tectonic changes and ongoing global cooling are probable causes of these changes in aridity and circulation in Asia.

Earliest presence of humans in northeast Asia

The timing of the earliest habitation and oldest stone technologies in different regions of the world remains a contentious topic in the study of human evolution. Here we contribute to this debate with detailed magnetostratigraphic results on two exposed parallel sections of lacustrine sediments at Xiaochangliang in the Nihewan Basin, north China; these results place stringent controls on the age of Palaeolithic stone artifacts that were originally reported over two decades ago. Our palaeomagnetic findings indicate that the artifact layer resides in a reverse polarity magnetozone bounded by the Olduvai and Jaramillo subchrons. Coupled with an estimated rate of sedimentation, these findings constrain the layer's age to roughly 1.36 million years ago. This result represents the age of the oldest known stone assemblage comprising recognizable types of Palaeolithic tool in east Asia, and the earliest definite occupation in this region as far north as 40 degrees N.

Purification of individual tRNAs using a monoclonal anti-AMP antibody affinity column

A murine monoclonal anti-AMP antibody affinity matrix was used for isolation of individual species of amino acid transfer nucleic acids (tRNAs). The antibodies had been prepared using 5'-AMP covalently attached to bovine serum albumin as antigen and exhibited high affinity for 5'-AMP but greatly reduced affinity for 3'-AMP. Native uncharged tRNAs that terminate in a 5'-AMP group on the amino acid acceptor arm of the molecule bind tightly to the anti-AMP affinity matrix, whereas aminoacylated tRNAs are not retained. This allows separation of a particular tRNA species as its aminoacyl derivative from a complex mixture of uncharged tRNAs under very mild conditions.