Spatial transcriptome reveals the region-specific genes and pathways regulated by Satb2 in neocortical development.

BACKGROUND: It is known that the neurodevelopmental disorder associated gene, Satb2, plays important roles in determining the upper layer neuron specification. However, it is not well known how this gene regulates other neocortical regions during the development. It is also lack of comprehensive delineation of its spatially regulatory pathways in neocortical development. RESULTS: In this work, we utilized spatial transcriptomics and immuno-staining to systematically investigate the region-specific gene regulation of Satb2 by comparing the Satb2+/+ and Satb2-/- mice at embryonic stages, including the ventricle zone (VZ) or subventricle zone (SVZ), intermediate zone (IZ) and cortical plate (CP) respectively. The staining result reveals that these three regions become moderately or significantly thinner in the Satb2-/- mice. In the cellular level, the cell number increases in the VZ/SVZ, whereas the cell number decreases in the CP. The spatial transcriptomics data show that many important genes and relevant pathways are dysregulated in Satb2-/- mice in a region-specific manner. In the VZ/SVZ, the key genes involved in neural precursor cell proliferation, including the intermediate progenitor marker Tbr2 and the lactate production related gene Ldha, are up-regulated in Satb2-/- mice. In the IZ, the key genes in regulating neuronal differentiation and migration, such as Rnd2, exhibit ectopic expressions in the Satb2-/- mice. In the CP, the lineage-specific genes, Tbr1 and Bcl11b, are abnormally expressed. The neuropeptide related gene Npy is down-regulated in Satb2-/- mice. Finally, we validated the abnormal expressions of key regulators by using immunofluorescence or qPCR. CONCLUSIONS: In summary, our work provides insights on the region-specific genes and pathways which are regulated by Satb2 in neocortical development.

Genomes shed light on the evolution of Begonia, a mega-diverse genus.

Clarifying the evolutionary processes underlying species diversification and adaptation is a key focus of evolutionary biology. Begonia (Begoniaceae) is one of the most species-rich angiosperm genera with c. 2000 species, most of which are shade-adapted. Here, we present chromosome-scale genome assemblies for four species of Begonia (B. loranthoides, B. masoniana, B. darthvaderiana and B. peltatifolia), and whole genome shotgun data for an additional 74 Begonia representatives to investigate lineage evolution and shade adaptation of the genus. The four genome assemblies range in size from 331.75 Mb (B. peltatifolia) to 799.83 Mb (B. masoniana), and harbor 22 059-23 444 protein-coding genes. Synteny analysis revealed a lineage-specific whole-genome duplication (WGD) that occurred just before the diversification of Begonia. Functional enrichment of gene families retained after WGD highlights the significance of modified carbohydrate metabolism and photosynthesis possibly linked to shade adaptation in the genus, which is further supported by expansions of gene families involved in light perception and harvesting. Phylogenomic reconstructions and genomics studies indicate that genomic introgression has also played a role in the evolution of Begonia. Overall, this study provides valuable genomic resources for Begonia and suggests potential drivers underlying the diversity and adaptive evolution of this mega-diverse clade.

First Report of Didymella americana causing corn stalk rot in China.

Corn (Zea mays L.) is an important food crop and feedstuff worldwide. However, Corn stalk rot, caused by multiple pathogens, is globally an economic soil-borne disease worldwide. In September 2019, a survey was carried out to characterize pathogenic fungi in corn stalks in Nehe city (48.48°N 124.88°E), Heilongjiang Province, China. Stalk rot incidence was approximately 5% in three of the fields sampled (5 ha/per field). Symptoms included wilting of whole plants, drooping ears or rapid death of the upper leaves or whole plant from blister stage to physiological maturity (growth stages R2- R6) stage with drooping ears or rapid death of the upper leaves or whole plant. A brown to black dry rot or necrosis was observed throughout the central pith and internal tissues of the stalk and crown were observed, which resulted in hollow and soft stalks. Fifteen tissue samples (0.25 cm2) from 15 individual diseased plants were surface disinfested with 75% ethanol for 2 s, followed by 0.5% NaOCl for 5 min, rinsed three times in sterile distilled water and cultured on potato dextrose agar (PDA) with 50 µg/mL streptomycin at 26°C in darkness. After 3 days, a total of eight fungal isolates with consistent characteristics were obtained from three sampling points and subcultured by transferring hyphal tips onto a new PDA plate. Single-conidium isolates were generated with methods reported previously (Leslie and Summerell 2006). Cultures on PDA were honey to olivaceous buff in the center with dense aerial mycelia and wide buff colored margins. The dimensions of conidia from 30-day-old PDA cultures were 4.5 to 15.3 µm × 1.5 to 4.3 µm (n = 50). Often, one to two oil bodies were present within the conidia. Based on these morphological features, the isolates were identified as Didymella americana (Aveskamp et al. 2010; Gorny et al. 2016). Genomic DNA was extracted from a representative isolate YJDA8 and the internal transcribed spacer regions (ITS) and translation elongation factor 1-alpha gene (TEF-1ɑ) were amplified and sequenced using the primers ITS1/ITS4 (Yin et al. 2012) and EF1-728F/EF1-986R (Carbone and Kohn 1999), respectively. The sequences of YJDA8 (accession nos. MT995077 for ITS and MW003707 for TEF-1a ) showed 99.6% (529/531 bp) and 97.6% (283/290 bp), identity to the sequences of D. americana isolate YSGYE6 (accession no. MK945663.1) and isolate K_INSO2_6_10 (MN554764.1) respectively. Pathogenicity tests were conducted by root injection of corn plants at the blister stage in the field. Conidia were obtained from 30-day-old PDA cultures grown at 20°C with a 12 h photoperiod. A conidial suspension (1.5 ml of 1×105 conidia/mL) was injected into the base of the maize stems using a 5 ml syringe. For each treatment, 5 plants were inoculated. Plants injected with 1.5 ml distilled sterile water served as the control. After inoculation, the plants were managed using conventional methods. All inoculated plants showed symptoms 25 days after inoculation that were similar to those observed in the field, while no symptoms were observed on the control plants. The fungus was re-isolated and confirmed to be D. americana. D. americana has previously been reported on corn roots and soybean pods in the USA (Aveskamp et al. 2009 as Peyronellaea americana), on lima bean in Delaware and Maryland (Everts et al. 2020). To our knowledge, this is the first report of D. americana causing stalk rot on corn in China. Therefore, its distribution needs to be investigated, monitored and managed with effective disease management strategies to protect corn.

Development of an inoculation technique for rapidly evaluating maize inbred lines for resistance to stalk rot caused by Fusarium spp. in the field.

Maize (Zea mays L.) stalk rot, caused primarily by the soil-borne fungal pathogen Fusarium spp., reduces maize quality and yield worldwide. This study was undertaken to develop and utilize a rapid continuous injection inoculation technique to evaluate maize inbred lines for resistance to Fusarium spp. under field conditions, which could facilitate the identification and development of new sources of host resistance to manage the disease. Continuous injection inoculation is a rapid, stable, and simple method that can evaluate the resistance of maize inbred lines to Fusarium stalk rot (FSR) within 20 days. To verify the feasibility and reliability of inoculation method, Fusarium graminearum, F. proliferatum, and F. subglutinans were isolated, identified, and inoculated into maize at the six-leaf stage (V6) by a veterinary adjustable bottle continuous vaccination syringe. Our results showed that out of a total of 97 inbred maize lines, six (6.2%) showed high resistance to maize stalk rot, 20 showed resistance (20.6%), 32 were susceptible (33.0%), and 39 were very susceptible (40.2%). Based on simple sequence repeat (SSR) markers, an analysis of molecular variance indicated a significant correlation between population of the inbred maize line and resistance to FSR (P = 0.001). Overall, this study provided a systematic, rapid, stable, and simple identification method for maize inbred lines resistant to FSR in the field. At the same time, this method was also suitable for genetic diversity analysis of maize inbred lines resistant to FSR.

Colon Ascendens Stent Peritonitis (CASP) Induces Excessive Inflammation and Systemic Metabolic Dysfunction in a Septic Rat Model.

The colon ascendens stent peritonitis (CASP) surgery induces a leakage of gut contents, causing polymicrobial sepsis related to post-operative multiple organ failure and death in surgical patient. To evaluate the effects of CASP on multiple organs, we analyzed the systemic metabolic consequences in liver, kidney, lung, and heart of rats after CASP by employing a combination of metabolomics, clinical chemistry, and biological assays. We found that CASP surgery after 18 h resulted in striking elevations of lipid, amino acids, acetate, choline, PC, and GPC in rat liver together with significant depletion of glucose and glycogen. Marked elevations of organic acids including lactate, acetate, and creatine and amino acids accompanied by decline of glucose, betaine, TMAO, choline metabolites (PC and GPC) nucleotides, and a range of organic osmolytes such as myo-inositol are observed in the kidney of 18 h post-operative rat. Furthermore, 18 h post-operative rats exhibited accumulations of lipid, amino acids, and depletions of taurine, myo-inositol, choline, PC, and GPC and some nucleotides including uridine, inosine, and adenosine in the lung. In addition, significant elevations of some amino acids, uracil, betaine, and choline metabolites, together with depletion of inosine-5'-monophosphate, were only observed in the heart of 18 h post-operative rats. These results provide new insights into pathological consequences of CASP surgery, which are important for timely prognosis of sepsis.

The hornwort genome and early land plant evolution.

Hornworts, liverworts and mosses are three early diverging clades of land plants, and together comprise the bryophytes. Here, we report the draft genome sequence of the hornwort Anthoceros angustus. Phylogenomic inferences confirm the monophyly of bryophytes, with hornworts sister to liverworts and mosses. The simple morphology of hornworts correlates with low genetic redundancy in plant body plan, while the basic transcriptional regulation toolkit for plant development has already been established in this early land plant lineage. Although the Anthoceros genome is small and characterized by minimal redundancy, expansions are observed in gene families related to RNA editing, UV protection and desiccation tolerance. The genome of A. angustus bears the signatures of horizontally transferred genes from bacteria and fungi, in particular of genes operating in stress-response and metabolic pathways. Our study provides insight into the unique features of hornworts and their molecular adaptations to live on land.

The complete chloroplast genome of Magnolia sinostellata (Magnoliaceae), a rare and endangered species of China.

Magnolia sinostellata Chiu & Chen is a rare and endangered species endemic to subtropical China. Here we assembled and annotated the complete chloroplast (cp) genome of M. sinostellata. The chloroplast genome of M. sinostellata is 160,076 bp in length and encodes 79 protein-coding genes, 30 transfer RNA (tRNA) genes and four ribosomal RNA (rRNA) genes. The maximum-likelihood (ML) phylogenetic analysis result reveals that M. sinostellata is most closely related to M. biondii.

Effect of somatostatin versus octreotide on portal haemodynamics in patients with cirrhosis and portal hypertension.

OBJECTIVES: Elevated portal inflow is part of the pathogenesis of portal hypertension in patients with cirrhosis. Vasoactive substances appear to play a primary role in the regulation of portal flow. The aim of this study was to investigate the effects of somatostatin and octreotide on portal pressure and plasma levels of insulin-like growth factor (IGF-1), nitric oxide (NO), endothelin-1 (ET-1) and glucagon (GLU). METHODS: Portal pressures of 14 cirrhotic patients with portal hypertension who underwent transjugular intrahepatic portosystemic shunt (TIPS) were directly measured via a catheter placed in the portal vein. Portal pressure and IGF-1, NO, ET-1 and GLU plasma levels were determined at baseline, and at 8 h and 24 h after administration of somatostatin or octreotide via portal vein catheter in a randomized, double-blind, cross-over design. RESULTS: The average decrease in portal pressure after intravenous infusion of somatostatin and octreotide was 9.4 +/- 1.0 cmH2O and 5.0 +/- 1.0 cmH2O, respectively (P < 0.01). Plasma levels of GLU and IGF-1 decreased significantly 8 and 24 h after somatostatin and octreotide infusion (P < 0.05). However, there were no significant decreases in plasma NO or ET-1 levels. There was a significant difference between somatostatin and octreotide groups (P < 0.01). CONCLUSION: Both somatostatin and octreotide can significantly reduce portal pressure, although somatostatin is more potent than octreotide. The underlying mechanisms may involve inhibition of the secretion of GLU, IGF-1 and other hormones as well as a decrease in hepatic metabolism and portal inflow leading to a reduction in portal pressure.

[Diagnosis and treatment of abdominal cocoon].

OBJECTIVE: To study the clinical characteristics and the methods of diagnosis and treatment for abdominal cocoon. METHODS: The clinical data of 9 patients with abdominal cocoon treated from July 2000 to February 2004 were analyzed. RESULTS: The clinical manifestations included abdominal pain, abdominal distention, nausea, vomiting, partial or complete intestinal obstruction in 4 cases among 9 cases, abdominal mass in 5 cases. Abdominal plain X-ray and computed tomography suggested partial intestinal obstruction in 8 cases. Computed tomography suggested thickening and rigidity in peritoneum and intestinal wall even a part of calcification in 4 cases. The intestinal loops seemed to be encapsulated in a thickened capsule. Contrast study was negative in 1 case, partial intestinal obstruction in 1 case and intestinal loops fixed at middle abdomen in 1 case among 3 cases. All the cases underwent operations, which showed that part or all the small bowel were encapsulated in a dense white membrane. CONCLUSIONS: Abdominal cocoon is rare. It is more difficult to make right diagnosis preoperatively. A better awareness of this disease and the combination of clinic and radiology may be facilitated in preoperative diagnosis. Abdominal cocoon may be considered when recurrent acute or chronic intestinal obstruction. Surgery was the first choice of therapy.

Treatment of osteoporosis in men using dehydroepiandrosterone sulfate.

OBJECTIVE: To study the effect of dehydroepiandrosterone sulfate (DHEAS) treatment of osteoporosis in men with T(BMD) > or = 2.5SD. METHODS: Eighty-six patients were randomly divided into two groups: treatment group (n = 44) and control group (n = 42). DHEAS (100 mg q.d.) was given to the treatment group for 6 months. Bone mineral density, (BMD), biochemical markers of bone absorption and formation and other serum biochemical markers were measured before and after DHEAS treatment. Drug side effects were also evaluated. RESULTS: After oral administration of DHEAS (100 mg q.d.) for 6 months, the serum concentrations of DHEAS and IGF-I in the treatment group were 93.75% +/- 16.1% and 17.71% +/- 4.2% higher respectively than those in the control group (P < 0.01). The BMD of L2, L3, L4, L2 - 4 and Neck sections increased in the treatment group by 2.65% +/- 0.65%, 2.70% +/- 0.48%, 3.10% +/- 0.41%, 2.82% +/- 0.37% and 2.32% +/- 0.31%, respectively, as compared with that the control group (P < 0.05 or 0.01). No significant changes were observed in serum FT, E(2) and PSA concentrations in the treatment group as compared with the control group. CONCLUSION: The treatment of osteoporosis in men with DHEAS is safe and effective.