Liberibacter crescens Is a Cultured Surrogate for Functional Genomics of Uncultured Pathogenic 'Candidatus Liberibacter' spp. and Is Naturally Competent for Transformation

'Candidatus Liberibacter' spp. are uncultured insect endosymbionts and phloem-limited bacterial plant pathogens associated with diseases ranging from severe to nearly asymptomatic. 'Ca. L. asiaticus', causal agent of Huanglongbing or citrus "greening," and 'Ca. L. solanacearum', causal agent of potato zebra chip disease, respectively threaten citrus and potato production worldwide. Research on both pathogens has been stymied by the inability to culture these agents and to reinoculate into any host. Only a single isolate of a single species of Liberibacter, Liberibacter crescens, has been axenically cultured. L. crescens strain BT-1 is genetically tractable to standard molecular manipulation techniques and has been developed as a surrogate model for functional studies of genes, regulatory elements, promoters, and secreted effectors derived from the uncultured pathogenic Liberibacters. Detailed, step-by-step, and highly reproducible protocols for axenic culture, transformation, and targeted gene knockouts of L. crescens are described. In the course of developing these protocols, we found that L. crescens is also naturally competent for direct uptake and homology-guided chromosomal integration of both linear and circular plasmid DNA. The efficiency of natural transformation was about an order of magnitude higher using circular plasmid DNA compared with linearized fragments. Natural transformation using a replicative plasmid was obtained at a rate of approximately 900 transformants per microgram of plasmid, whereas electroporation using the same plasmid resulted in 6 × 10⁴ transformants. Homology-guided marker interruptions using either natural uptake or electroporation of nonreplicative plasmids yielded 10 to 12 transformation events per microgram of DNA, whereas similar interruptions using linear fragments via natural uptake yielded up to 34 transformation events per microgram of DNA.

Genera of phytopathogenic fungi: GOPHY 3

This paper represents the third contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions, information about the pathology, distribution, hosts and disease symptoms for the treated genera, as well as primary and secondary DNA barcodes for the currently accepted species included in these. This third paper in the GOPHY series treats 21 genera of phytopathogenic fungi and their relatives including: Allophoma, Alternaria, Brunneosphaerella, Elsinoe, Exserohilum, Neosetophoma, Neostagonospora, Nothophoma, Parastagonospora, Phaeosphaeriopsis, Pleiocarpon, Pyrenophora, Ramichloridium, Seifertia, Seiridium, Septoriella, Setophoma, Stagonosporopsis, Stemphylium, Tubakia and Zasmidium. This study includes three new genera, 42 new species, 23 new combinations, four new names, and three typifications of older names.

[Relationship between selenium and the risk for oral cancer: a case-control study]

Objective: To explore the relationship between selenium and the risk for oral cancer. Methods: We performed a case-control study in 325 cases of newly diagnosed primary oral cancer from the First Affiliated Hospital of Fujian Medical University and 650 controls from the same hospital and community. Unconditional logistic regression and stratification analyses were used to explore the association between selenium and oral cancer. Adjusted OR and corresponding 95%CI were calculated. The analyses on multiple interactions between selenium and smoking or drinking status, and fruit or fish intake frequencies were conducted. Results: The level of serum selenium was 112.42 (80.98-145.06) μg/L in the case group, which was lower than 164.85 (144.44-188.53) μg/L in control group, the difference was statistical significant (P<0.01). There was a negative correlation between serum selenium level and the risk for oral cancer regardless of smoking and drinking status, and fruits and fish intake frequencies (P<0.05). There were multiple interactions between serum selenium level and smoking or drinking status, and fruit and fish intakes. Conclusions: The high level of serum selenium is a protective factor for the incidence of oral cancer, and serum selenium has multiple interactions with smoking or drinking status, and fruit and fish intakes. Therefore, reducing tobacco use and alcohol consumption and increasing the intakes of fruit and fish can reduce the risk for oral cancer to some extent.

Fusarium incarnatum-equiseti complex from China

The Fusarium incarnatum-equiseti species complex (FIESC) is shown to encompass 33 phylogenetic species, across a wide range of habitats/hosts around the world. Here, 77 pathogenic and endophytic FIESC strains collected from China were studied to investigate the phylogenetic relationships within FIESC, based on a polyphasic approach combining morphological characters, multi-locus phylogeny and distribution patterns. The importance of standardised cultural methods to the identification and classification of taxa in the FIESC is highlighted. Morphological features of macroconidia, including the shape, size and septum number, were considered as diagnostic characters within the FIESC. A multi-locus dataset encompassing the 5.8S nuclear ribosomal gene with the two flanking internal transcribed spacers (ITS), translation elongation factor (EF-1α), calmodulin (CAM), partial RNA polymerase largest subunit (RPB1) and partial RNA polymerase second largest subunit (RPB2), was generated to distinguish species within the FIESC. Nine novel species were identified and described. The RPB2 locus is demonstrated to be a primary barcode with high success rate in amplification, and to have the best species delimitation compared to the other four tested loci.

Setophoma spp. on Camellia sinensis

During our investigation of Camellia sinensis diseases (2013–2018), a new leaf spot disease was found in seven provinces of China (Anhui, Fujian, Guangxi, Guizhou, Jiangxi, Tibet and Yunnan), occurring on both arboreal and terraced tea plants. The leaf spots were round to irregular, brown to dark brown, with grey or tangerine margins. Multi-locus (LSU, ITS, gapdh, tef-1α, tub2) phylogenetic analyses combined with morphological observations revealed four new species belonging to the genus Setophoma, i.e.S. antiqua, S. longinqua, S. yingyisheniae and S. yunnanensis. Of these four species, S. yingyisheniae was found to be present on diseased terraced tea plants in six of the seven sampled provinces (excluding Yunnan). The other three species only occurred on arboreal tea plants in Yunnan Province. In addition to the four species isolated from diseased leaves, S. endophytica sp. nov. was isolated from healthy leaves of terraced tea plants.

[Association of single nucleotide polymorphisms of TBX5 gene and environmental exposure index with susceptibility to oral cancer]

Objective: To explore the association of TBX5 polymorphisms and environmental exposure index with susceptibility to oral cancer. Methods: A case-control study was conducted to collect 300 oral cancer patients hospitalized in the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Fujian Medical University from September 2010 to December 2016. A total of 445 non-tumor patients were selected as the control group. Questionnaires were used to collect the information of all subjects and 5 ml peripheral blood was collected to detect single nucleotide polymorphisms (SNPs) of the rs10492336 locus of TBX5 gene. According to the environmental exposure index score, subjects were divided into two groups, low risk group (0-2.31) and high risk group (2.32-11.76). To analyze the association of TBX5 gene rs10492336 SNPs, environmental exposure index and oral cancer and its interactions. Results: The age of all subjects in the case group and control group were (56.19±13.10) years and (54.56±12.48) years old. Compared with CC genotype, the OR (95%CI) values of the co-dominant genetic model AC genotype and the dominant genetic model AC+AA genotype were 0.69 (0.49-0.98) and 0.70 (0.51-0.97), respectively. Compared with the low risk group, the OR (95%CI) risk of oral cancer in the high risk group was 3.72 (2.55-5.43). The results of gene-environment interaction analysis showed that compared with the group with CC genotype and high risk of environmental exposure index, the OR (95%CI) value of oral cancer in the group with AC+AA genotype and low risk of environmental exposure index was 0.18(0.10-0.31). Furthermore there was a multiplicative interaction between rs10492336 SNPs and environmental exposure index (β=-0.405, P<0.001). Conclusion: This study suggests that the TBX5 gene rs10492336 SNPs and environmental exposure index were associated with oral cancer. And there was a multiplication interaction between rs10492336 SNPs and environmental exposure index.

[Association between polymorphism in notch signaling pathway and lung cancer risk]

Objective: To analyze the relationship between single nucleotide polymorphisms (SNP) of Notch signaling pathway and susceptibility to lung cancer. Methods: The present study was a hospital-based case-control study. All 1 121 patients of lung cancer diagnosed by histopathology three hospitals in Fujian and Nanjing were selected as cases from January 2006 to December 2012. At the same time, 1 121 healthy population from other departments of the hospital to visit patients or community, excluding those with tumor, chronic disease, and immediate family members of lung cancer, were enrolled in control group. A uniform questionnaire was used to collect general information. Matrix-assisted laster desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) was used to identify the polymorphisms of 9 SNP (Notch3 rs3815188, Notch4 rs915894, Notch4 rs520692, DLL1 rs1033583, JAG1 rs8708, JAG2 rs9972231, HEY1 rs1046472, HEY2 rs3734637, HES2 rs11364) in 1 121 lung cancer patients and 1 121 healthy controls. The association between SNP and lung cancer was analyzed by χ(2) and logistic regression model. Results: The average age of cases and controls was (58.70±10.73) and (58.98±10.85) years old. The OR for genotype AC carriers of HEY1 rs1046472 was 0.80 (95%CI: 0.66-0.97) when comparing with genotype CC. The OR for genotype AC+AA carriers of HEY1 rs1046472 was 0.81 (95% CI: 0.67-0.98) when comparing with genotype CC. The OR for genotype AC carriers of HEY2 rs3734637 was 0.82 (95%CI: 0.67-0.99) when comparing with genotype AA. In the stratified analysis, Notch3 rs3815188, DLL1 rs1033583, JAG1 rs8708, JAG2 rs9972231, HEY1 rs1046472, HEY2 rs3734637, HES2 rs11364 were associatied with the risk of lung cancer, P were 0.041, 0.030, 0.043, 0.003, 0.004, 0.026 and 0.038, respectively.The interactions analysis done by logistic regression model showed JAG1 rs8708 and family history, JAG2 rs9972231 and BMI had interaction in the study, OR were 2.07 (95% CI:1.21-3.52) and 1.73 (95% CI:1.21-2.47), respectively. Conclusion: Notch3 rs3815188, DLL1 rs1033583, JAG1 rs8708, JAG2 rs9972231, HEY1 rs1046472, HEY2 rs3734637 and HES2 rs11364 were significantly associated with susceptibility to lung cancer.

Heparin-binding EGF-like growth factor (HB-EGF) antisense oligonucleotide protected against hyperlipidemia-associated atherosclerosis

BACKGROUND AND AIMS

Heparin-binding EGF-like growth factor (HB-EGF) is a representative EGF family member that interacts with EGFR under diverse stress environment. Previously, we reported that the HB-EGF-targeting using antisense oligonucleotide (ASO) effectively suppressed an aortic aneurysm in the vessel wall and circulatory lipid levels. In this study, we further examined the effects of the HB-EGF ASO administration on the development of hyperlipidemia-associated atherosclerosis using an atherogenic mouse model.

METHODS AND RESULTS

The male and female LDLR deficient mice under Western diet containing 21% fat and 0.2% cholesterol content were cotreated with control and HB-EGF ASOs for 12 weeks. We observed that the HB-EGF ASO administration effectively downregulated circulatory VLDL- and LDL-associated lipid levels in circulation; concordantly, the HB-EGF targeting effectively suppressed the development of atherosclerosis in the aorta. An EGFR blocker BIBX1382 administration suppressed the hepatic TG secretion rate, suggesting a positive role of the HB-EGF signaling for the hepatic VLDL production. We newly observed that there was a significant improvement of the insulin sensitivity by the HB-EGF ASO administration in a mouse model under the Western diet as demonstrated by the improvement of the glucose and insulin tolerances.

CONCLUSION

The HB-EGF ASO administration effectively downregulated circulatory lipid levels by suppressing hepatic VLDL production rate, which leads to effective protection against atherosclerosis in the vascular wall.

Sporocadaceae, a family of coelomycetous fungi with appendage-bearing conidia

Species of Sporocadaceae are endophytic, plant pathogenic or saprobic, and associated with a wide range of host plants. Recent molecular studies that have attempted to address familial and generic boundaries of fungi belonging to Sporocadaceae were based on a limited number of samples and DNA loci. The taxonomy of this group of fungi is therefore still not fully resolved. The aim of the present study is to provide a natural classification for the Sporocadaceae based on multi-locus phylogenetic analyses, using LSU, ITS, tef-1α, tub2 and rpb2 loci, in combination with morphological data. A total of 30 well-supported monophyletic clades in Sporocadaceae are recognised, representing 23 known and seven new genera. Typifications are proposed for the type species of five genera (Diploceras, Discosia, Monochaetia, Sporocadus and Truncatella) to stabilise the application of these names. Furthermore, Neotruncatella and Dyrithiopsis are synonymised under Hymenopleella, and the generic circumscriptions of Diploceras, Disaeta, Hymenopleella, Monochaetia, Morinia, Pseudopestalotiopsis, Sarcostroma, Seimatosporium, Synnemapestaloides and Truncatella are emended. A total of 51 new species, one nomina nova and 15 combinations are introduced.

Raman spectroscopy-based water content is a negative predictor of articular human cartilage mechanical function

OBJECTIVE

Probing the change in water content is an emerging approach to assess early diagnosis of osteoarthritis (OA). We herein developed a new method to assess hydration status of cartilage nondestructively using Raman spectroscopy (RS), and showed association of Raman-based water and organic content measurement with mechanical properties of cartilage. We further compared Raman-based water measurement to gravimetric and magnetic resonance imaging (MRI)-based water measurement.

DESIGN

Eighteen cadaveric human articular cartilage plugs from 6 donors were evenly divided into two age groups: young (n = 9, mean age: 29.3 ± 6.6) and old (n = 9, mean age: 64.0 ± 1.5). Water content in cartilage was measured using RS, gravimetric, and MRI-based techniques. Using confined compression creep test, permeability and aggregate modulus were calculated. Regression analyses were performed among RS parameters, MRI parameter, permeability, aggregate modulus and gravimetrically measured water content.

RESULTS

Regardless of the method used to calculate water content (gravimetric, RS and MRI), older cartilage group consistently had higher water content compared to younger group. There was a stronger association between gravimetric and RS-based water measurement (R_g² = 0.912) than between gravimetric and MRI-based water measurement (R_c² = 0.530). Gravimetric and RS-based water contents were significantly correlated with permeability and aggregate modulus whereas MRI-based water measurement was not.

CONCLUSION

RS allows for quantification of different water compartments in cartilage nondestructively, and estimation of up to 82% of the variation observed in the permeability and aggregate modulus of articular cartilage. RS has the potential to be used clinically to monitor cartilage quality noninvasively or minimally invasively with Raman probe during arthroscopy procedures.

Association between PPARs Gene Functional Polymorphisms and Ischemic Stroke in Chinese Uyghur Population

PPARγ and PPARα belong to a receptor family of ligand-activated transcription factors involved in the regulation of inflammation, cellular glucose uptake, protection against atherosclerosis and endothelial cell function. Through these effects, they might be involved with the ischemic stroke (IS). We recruited 100 IS patients diagnosed by CTs or/and magnetic resonance imaging (MRI) and 100 normal healthy controls from Chinese Uyghur Population to assess the nature of the functional polymorphisms of PPARs and any links with IS in this unique population which has 60% European ancestry and 40% East Asian ancestry. We found that the Ala allele of the PPARγ Pro12Ala polymorphism was more common in controls than IS subjects (P = 0.008, corrected for multiple testing) in the Uyghur Population. Pro/Ala carriage may be associated with a decreased risk of IS in Uyghurs (OR 0.542, 95% CI 0.346-0.850). Additionally, the 162Val allele frequency at the DNA-binding region of PPARα was extremely rare in Chinese Uguhur IS patients and controls. Our population and ethnic-based study demonstrates that the 162Val allele frequency was extremely low in the Chinese Uyghur Population different from Some European and African populations and the PPARγ 12 Pro/Ala resulting in an amino acid exchange in N-terminal sequence may be an independent protective factor for IS in the Chinese Uyghur Population.

Allelochaeta (Sporocadaceae): pigmentation lost and gained

The appendaged coelomycete genus Seimatosporium (Sporocadaceae, Sordariomycetes) and some of its purported synonyms Allelochaeta, Diploceras and Vermisporium are re-evaluated. Based on DNA data for five loci (ITS, LSU, rpb2, tub2 and tef1), Seimatosporium is shown to be paraphyletic. The ex-type species of Allelochaeta, Discostromopsis and Vermisporium represent a distinct sister clade to which the oldest name Allelochaeta is applied. These genera were traditionally separated based on a combination of conidial pigmentation, septation, and the nature of their conidial appendages. Allelochaeta is revealed to include taxa with both branched or solitary appendages, that could be cellular or continuous, with conidia being (2-)3(-5)-septate, hyaline, or pigmented, concolourous or versicolourous. This suggests that these characters should be applied at species, and not at the generic level. Conidial pigmentation appears to have been lost or gained several times during the evolution of species within Allelochaeta. In total, 25 new species, 15 new combinations, and 10 new epitypifications are proposed.

Cartilage-on-cartilage contact: effect of compressive loading on tissue deformations and structural integrity of bovine articular cartilage

OBJECTIVE

This study aims to characterize the deformations in articular cartilage under compressive loading and link these to changes in the extracellular matrix constituents described by magnetic resonance imaging (MRI) relaxation times in an experimental model mimicking in vivo cartilage-on-cartilage contact.

DESIGN

Quantitative MRI images, T₁, T₂ and T_1ρ relaxation times, were acquired at 9.4T from bovine femoral osteochondral explants before and immediately after loading. Two-dimensional intra-tissue displacement and strain fields under cyclic compressive loading (350N) were measured using the displacement encoding with stimulated echoes (DENSE) method. Changes in relaxation times in response to loading were evaluated against the deformation fields.

RESULTS

Deformation fields showed consistent patterns among all specimens, with maximal strains at the articular surface that decrease with tissue depth. Axial and transverse strains were maximal around the center of the contact region, whereas shear strains were minimal around the contact center but increased towards contact edges. A decrease in T₂ and T_1ρ was observed immediately after loading whereas the opposite was observed for T₁. No correlations between cartilage deformation patterns and changes in relaxation times were observed.

CONCLUSIONS

Displacement encoding combined with relaxometry by MRI can noninvasively monitor the cartilage biomechanical and biochemical properties associated with loading. The deformation fields reveal complex patterns reflecting the depth-dependent mechanical properties, but intra-tissue deformation under compressive loading does not correlate with structural and compositional changes. The compacting effect of cyclic compression on the cartilage tissue was revealed by the change in relaxation time immediately after loading.

Longitudinal melanonychia and subungual hemorrhage in a patient with systemic lupus erythematosus treated with hydroxychloroquine

Hydroxychloroquine is an antimalarial agent, most commonly prescribed in the treatment of several rheumatic diseases. Although generally well tolerated, a variety of mucocutaneous adverse effects have been reported. Besides the familiar adverse effects, longitudinal melanonychia is rarely seen. Although the incidence is extremely low, systemic lupus erythematosus may also cause nail pigmentation in its own right. We report the case of a 55-year-old woman who was diagnosed with systemic lupus erythematosus and presented with longitudinal melanonychia of all 10 fingernails after 3 years of treatment with hydroxychloroquine, without mucocutaneous hyperpigmentation. The pigment of the nail lasted for more than 15 years. To the best of our knowledge, this is first published report of hydroxychloroquine-induced melanonychia without mucocutaneous hyperpigmentation. This case demonstrates that hydroxychloroquine treatment and the primary disease should be considered in the case of multiple nail changes in patients with systemic lupus erythematosus.

Effects of chronic dexamethasone exposure on bile acid metabolism and cecal epithelia function in goats

Bile acids (BAs) are synthesized in the liver via the oxidation of cholesterol and further metabolized by microbiota in the gut, where they simultaneously impact gut function. In the present study, 10 goats were randomly divided into 2 groups; 1 group was injected with dexamethasone (Dex; 0.2 mg/kg), and the other group was injected with saline as the control (Con) for 21 d. Expression levels of key genes and proteins in the liver and gut mucosa were analyzed and compared to investigate the impact of chronic stress on BA metabolism and related functions in ruminants. The results revealed that Dex decreased plasma total BAs (TBAs) concentration (P < 0.05) but increased TBA concentration in the cecal digesta (P < 0.05). Total cholesterol in the liver decreased moderately in response to Dex. The protein expression of cytochrome P450 family 7 subfamily A member 1 and cytochrome P450 family 27 subfamily A member 1, 2 enzymes that control BA synthesis in the liver, remained unchanged by Dex administration (P > 0.05). The expression of several genes in the cecal mucosa encoding epithelial tight junction proteins, including occludin (P < 0.05), tight junction protein 1 (P < 0.01), and claudin 1 (P < 0.05), increased significantly in response to Dex, and expression of defensin beta 1, which can strengthen the innate immune system, was also upregulated (P < 0.05). In addition, BAs increased the expression of the Solute Carrier family 9 member A 2 (P < 0.01) that encodes a sodium hydrogen exchanger. These results suggest that the Dex-induced disruption of BA homeostasis might be mediated through a liver-independent pathway in goats, and the Dex-induced accumulation of TBAs in the cecal digesta may improve volatile fatty acid transportation and mucosal defense.

[A case report of cutaneous plasmacytosis]

A collection of plasma cells in the skin can represent a broad spectrum of disease entities. Secondary syphilis, primary cutaneous plasmacytoma, primary cutaneous plasmacytosis, cutaneous lymphoid hyperplasia and nodular amyloidosis are considered possible differential diagnoses. The primary cutaneous plasma cell disorders can range from malignant to benign plasma cell neoplasms. The malignant conditions are neoplastic diseases having monoclonal proliferations, rapid progression and fatal outcome while the benign plasma cell disorders usually show polyclonality, chronicity and benign process, including plasmacytosis. We present a case of cutaneous plasmacytosis. The patient was a 34-year-old man, presented with disseminated reddish-brown plaques and nodules on the right side of the hips, inguinal groove, and the thigh. Histopathologically, mature plasma cells perivascular infiltrates were observed mainly in the dermis. Polyclonality of infiltrating plasma cells with coexistence of both kappa and gamma chain-positive cells demonstrated with immunohistochemistry, as well as CD20+++, CD38++++, CD79a++++, CD138++, Ki67<30%. The diagnosis, cutaneous plasmacytosis, was established by the pertinent laboratory findings. Primary cutaneous plasmacytosis was an uncommon reactive lymphoplasmacytic disorder of uncertain etiology. Cutaneous plasmacytosis is a rare disease characterized by peculiar multiple eruptions and hyper gamma globulinemia. It has been mainly described in patients of Japanese descent, with only few reports in Caucasians and Chinese, although information concerning the disorder was limited to individual case reports. Cutaneous plasmacytosis is a rare disorder, which is characterized by multiple red to dark-brown nodules and plaques on the trunk and usually associated with polyclonal hyper gamma globulinaemia. Primary cutaneous plasmacytosis or cutaneous plasmacytosis was thought to be a reactive process with unknown etiology. Histologically, lesions contain dense perivascular infiltration of mature polyclonal plasma cells without any atypia, in the dermis and subcutaneous fat. The clinical course is chronic and benign without spontaneous remission. Available treatments for cutaneous plasmacytosis include psoralen ultraviolet A radiotherapy, systemic chemotherapy and intralesional steroid injection. The patient with cutaneous plasmacytosis in this report was treated with tacrolimus ointment and psoralen ultraviolet A.

Neutralization of Enoxaparine-lnduced Bleeding by Protamine Sulfate

It has been suggested that protamine sulfate is a poor antidote for the bleeding side-effeets of low molecular weight heparins (LMWHs) in vivo, since protamine sulfate does not completely neutralize the anti-factor Xa activity of LMWHs in vitro or ex vivo. Therefore, we performed experiments to compare directly the abilities of protamine sulfate to neutralize the anticoagulant activities of the LMWH, enoxaparine, and unfractionated heparin ex vivo, with its ability to neutralize the bleeding side-effeets of both compounds in vivo. Bleeding was measured as the amount of blood lost from 5 cuts made in rabbits ears before and after treatment with enoxaparine or unfractionated heparin ± protamine sulfate. Plasma anti-factor Xa and anti-thrombin activities ex vivo, were measured chromogenically. Doses of 400 and 1,500 anti-factor Xa U/kg of heparin and enoxaparine, respectively, were required to enhance blood loss to the same extent. Protamine sulfate completely neutralized blood loss induced by both compounds, but did not neutralize the anti-factor Xa nor antithrombin activities ex vivo. We conclude that protamine sulfate is an effective antidote for the bleeding side-effeets of enoxaparine and unfractionated heparin, despite its inability to completely neutralize their anticoagulant activities.