Fungal community structure shifts in litter degradation along forest succession induced by pine wilt disease

Fungi play a crucial role in decomposing litter and facilitating the energy flow between aboveground plants and underground soil in forest ecosystems. However, our understanding how the fungal community involved in litter decomposition responds during forest succession, particularly in disease-driven succession, is still limited. This study investigated the activity of degrading enzyme, fungal community, and predicted function in litter after one year of decomposition in different types of forests during a forest succession gradient from coniferous to deciduous forest, induced by pine wilt disease. The results showed that the weight loss of needles/leaves and twigs did not change along the succession process, but twigs degraded faster than needles/leaves in both pure pine forest and mixed forest. In pure pine forest, peak activities of enzymes involved in carbon degradation (β-cellobiosidase, β-glucosidase, β-D-glucuronidase, β-xylosidase), nitrogen degradation (N-acetyl-glucosamidase), and organic phosphorus degradation (phosphatase) were observed in needles, which subsequently declined. The fungal diversity and evenness (Shannon's diversity and Shannon's evenness) dropped in twig from coniferous forest to mixed forest during the succession. The dominant phyla in needle/leaf and twig litters were Ascomycota (46.9%) and Basidiomycota (38.9%), with Lambertella pruni and Chalara hughesii identified as the most abundant indicator species. Gymnopus and Desmazierella showed positively correlations with most measured enzyme activities. Functionally, saprotrophs constituted the main trophic mode (47.65%), followed by Pathotroph-Saprotroph-Symbiotroph (30.95%) and Saprotroph-Symbiotroph (10.57%). The fungal community and predicted functional structures in both litter types shifted among different forest types along the succession. These findings indicate that the fungal community in litter decomposition responds differently to disease-induced succession, leading to significant shifts in both the fungal community structure and function.

[Analysis of Gene Recombination between HLA-B and -DRB1, HLA-DQB1 and -DPB1 Loci]

OBJECTIVE

To investigate the recombinations within the human leukocyte antigen (HLA) region in two families.

METHODS

Genomic DNA was extracted from the peripheral blood specimens of the different family members. HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 loci were genotyped using polymerase chain reaction-sequence specific oligonucleotide probing technique (PCR-SSO) and next-generation sequencing technique. HLA haplotype was determined by genetic analysis of the pedigree.

RESULTS

The haplotypes of HLA-A*11:01~C*03:04~B*13:01~DRB1*12:02~DQB1*03:01~DPB1*05:01:01G and HLA-A*03:01~C*04:01~B*35:03~DRB1*12:01~DQB1*03:01~DPB1*04:01:01G in the family 1 were recombined between HLA-B and HLA-DRB1 loci, which formed the haplotype of HLA-A*11:01~C*03:04~B*13:01~DRB1* 12:01~DQB1*03:01~DPB1*04:01:01G. The haplotypes of HLA-A *02:06~C*03:03~B*35:01~DRB1*08:02~DQB1*04:02~ DPB1*13:01:01G and HLA-A *11:01~C*07:02~B*38:02~DRB1*15:02~DQB1*05:01~DPB1*05:01:01G in the family 2 were recombined between HLA-DQB1 and HLA-DPB1 loci, which formed the haplotype of HLA-A*02:06~C*03:03~B*35:01~ DRB1*08:02~DQB1*04:02~DPB1*05:01:01G.

CONCLUSION

The gene recombination events between HLA-B and -DRB1, HLA-DQB1 and -DPB1 loci were found respectively in two Chinese Han families.

Diverse Host Spectrum and the Parasitic Process in the Pantropical Hemiparasite Cassytha filiformis L. (Lauraceae) in China

Many hemiparasites attach to a range of different host species, resulting in complex parasite–host interactions. Comprehensive molecular phylogenies allow the investigation of evolutionary relationships between these host plants. We surveyed the hosts of the laurel dodder (Cassytha filiformis, Lauraceae) in China, representing 184 species from 146 genera, 67 families, and spanning flowering plants, conifers, and ferns, using host phylogenetic relationships to investigate the susceptibility to attack by this hemiparasitic plant among the vascular plants. The process of produced well-formed haustoria by C. filiformis was also observed in detail for six different hosts. Our results show that C. filiformis grows mainly on trees and shrubs from phylogenetically divergent members of the rosid and asterid eudicot clades, often attacking multiple adjacent hosts simultaneously, and forming extensive colonies. However, whether and to what extent transitions between C. filiformis and host plants occur remain unclear. Physiological evidence for the complex parasite–host species interactions need to be studied in the future.

A new species (Begoniagiganticaulis) of Begoniaceae from southern Xizang (Tibet) of China

Begoniagiganticaulis, a huge new species in Begoniasect.Platycentrum of Begoniaceae from southern Xizang (Tibet) of China, is described. Morphologically, it is mostly similar to B.longifolia and B.acetosella, but clearly differs from the former mainly by its dioecious and taller plants, sparse hairs on abaxial veins, longer inflorescence, unique shape of fruits, and differs from the latter mainly by its late and longer flowering time, 6-tepals of female flower and 3-loculed ovary. The phylogenetic analyses also support the separation of the new species from other taxa. Based on the current data, its conservation status is assigned to Endangered (B2a) according to the IUCN Red List Categories and Criteria.

Begonia catbensis (sect. Coelocentrum, Begoniaceae), a new species from northern Vietnam

Begonia catbensis, a new species in Begonia sect. Coelocentrum is described and illustrated. The new species was discovered in lowland limestone hills at Cat Ba National Park and can be easily distinguished from all its congeners by having dendritic hairs on the petiole, adaxial veins and stipules, fimbriate bracts and bracteoles, dense conical bullae on the upper surface of the leaf blade, two tepals in the pistillate flowers and a glabrescent ovary with verrucose wings. Based on IUCN Criteria, the species is currently assessed as "Endangered" (D).

[Effects of shading on photosynthetic characteristics and chlorophyll fluorescence parameters of four Corydalis species]

We examined the effects of five shading treatments (0, 20%, 40%, 60% and 80% shading) on chlorophyll content, photosynthetic characteristics, and chlorophyll fluorescence chara-cteristics of four Corydalis species (C. incisa, C. decumbens, C. edulis and C. pallida) in a pot experiment. The results showed that the contents of chlorophyll a, chlorophyll b and chlorophyll (a+b) increased with the increment of shading, with that of C. incisa reaching the maximum under 80% shading treatment and that of C. decumbens, C. edulis and C. pallida reaching a maximum under 60% shading treatment. In contrast, chlorophyll a/b, light saturation point, light compensation point and dark respiration rate decreased with increasing shading. Among the four Corydalis species, C. incisa reached up to the maximum chlorophyll fluorescence parameters under 80% shading treatment, and C. decumbens, C. edulis and C. pallida reached the maximum at 60% shading treatment. The shade tolerance of four species was as follows: C. incisa ＞ C. decumbens ＞ C. edulis ＞ C. pallida. C. incisa under 80% shading treatment and C. decumbens, C. edulis, C. pallida at 60% shading treatment had the highest light energy utilization and photosynthetic capacity, which would facilitate their growth.

Lysimachia fanii, a new species of Primulaceae from limestone area of Guangxi, China

Lysimachia fanii, a new species of Lysimachia (Subgen. Idiophyton, Primulaceae), is described and illustrated from Guangxi, China based on morphological and molecular data. Lysimachia fanii differs from L. verbascifolia, L. rupestris and L. alpestris mainly by the habit being nearly rosulate, leaves congested at the apex of the rhizome, leaf blades spatulate to narrowly oblanceolate and flowers solitary. Phylogenetic analyses supported L. verbascifolia as sister to L. fanii. This new species is endemic to limestone areas in Liucheng county of Guangxi, China.

Cerebellar Fastigial Nucleus Stimulation in a Chronic Unpredictable Mild Stress Rat Model Reduces Post-Stroke Depression by Suppressing Brain Inflammation via the microRNA-29c/TNFRSF1A Signaling Pathway

Background

We previously reported that cerebellar fastigial nucleus stimulation reduced post-stroke depression in a rat model by reducing inflammation. This study aimed to investigate the molecular inflammatory signaling pathways associated with cerebellar fastigial nucleus stimulation in an established rat model of post-stroke depression.

Material/Methods

Twenty-four Sprague-Dawley rats included a sham group (N=6), an untreated stroke group (N=6), an untreated post-stroke depression model group (PSD) (N=6), and the model group treated with cerebellar fastigial nucleus stimulation (FNS) (N=6). The rat stroke model involved occlusion of the middle cerebral artery occlusion (MCAO). Post-stroke depression model was established using chronic unpredictable mild stress treatment and was verified using an open field test. Real-time polymerase chain reaction (PCR) and Western blot compared expression levels of microRNA-29c (miR-29c), miR-676, TNFRSF1A, tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β in cerebellar tissue. U251 human glioblastoma cells and SH-SY5Y human neuroblastoma cells were studied in vitro.

Results

Cerebellar fastigial nucleus stimulation reduced behaviors associated with depression in the rat model, upregulated the expression of miR-29c, and reduced the expression of TNFRSF1A and inflammatory cytokines, and mildly reduced neuronal apoptosis. Bioinformatics data analysis identified a regulatory relationship between miR-29c and TNFRSF1A. SH-SY5Y cells treated with a miR-29c mimic, or TNFRSF1A short interfering RNA (siRNA), identified a negative regulatory relationship between TNFRSF1A and miR-29c.

Conclusions

In a rat model, cerebellar fastigial nucleus stimulation reduced the expression of TNFRSF1A by upregulating miR-29c expression, which suppressed the expression of inflammatory cytokines, resulting in reduced severity of post-stroke depression.

The complete plastid genome sequence of Begonia guangxiensis

Begonia guangxiensis was assessed as endangered according to Red List of Chinese Plants. In this study, we described the complete plastid genome of B. guangxiensis. The plastid genome sequence of B. guangxiensis is 157,648 bp in size, having a large single-copy region (LSC) of 86,514 bp, a small single-copy region (SSC) of 18,076 bp, and two inverted repeat (IR) regions of 26,529 bp. The complete plastid genome of B. guangxiensis encoding 112 unique genes including 79 protein-coding genes, 29 tRNA genes, and four rRNA genes. The overall GC content of the plastid genome is 35.9%. Phylogenetic analysis confirmed that B. guangxiensis is closely related to B. varipeltata.

Faecal and mucosal microbiota in patients with functional gastrointestinal disorders: Correlation with toll-like receptor 2/toll-like receptor 4 expression

AIM

To investigate the intestinal luminal microbiota (LM) and mucosa-associated microbiota (MAM) in Chinese patients with functional gastrointestinal disorders (FGIDs) and examine the association between these communities and the expression of toll-like receptor (TLR) 2 and TLR4.

METHODS

Thirty-two Chinese subjects who suffered from symptoms of FGIDs, as confirmed by gastroenterologists, were enrolled in this study. Fresh faecal samples and descending colonic mucosal biopsies were collected from the subjects before (faecal) and during (mucosal) flexible colonoscopy. For analysis of the samples, we performed high-throughput sequencing of the V3-V4 region of the 16S rRNA gene and reverse transcription (RT)-PCR to detect the expression of colonic TLR2 and TLR4. Differences in the stool and mucosal microbiota were examined and a correlation network analysis was performed.

RESULTS

The microbiota of faecal samples was significantly more diverse and richer than that of the mucosal samples, and the LM and MAM populations differed significantly. TLR2 expression showed a significant positive correlation with TLR4 expression. In the MAM samples, the genera Faecalibacterium and Ruminococcus, which belong to the family Ruminococcaceae, were inversely correlated with TLR4 expression (r = -0.45817, P = 0.0083 and r = -0.5306, P = 0.0018, respectively). Granulicatella, which belongs to Carnobacteriaceae, and Streptococcus, which belongs to Streptococcaceae, were inversely correlated with TLR2 expression (r = -0.5573, P = 0.0010 and r = -0.5435, P = 0.0013, respectively). In the LM samples, examination at phylum, class, or order level revealed no correlation with TLR4 expression. Faecalibacterium, which belongs to Ruminococcaceae, and Streptococcus, which belongs to Streptococcaceae, were inversely correlated with TLR2 expression (r = -0.5743, P = 0.0058 and r = -0.3905, P = 0.0271, respectively).

CONCLUSION

Microbial compositions of LM and MAM in Chinese patients with FGIDs are different. Expression of TLRs may be affected by the type of bacteria that are present in the gut.

[The correlation study between the changes of intestinal mucosa predominant bacteria and Toll-like receptor 2, Toll-like receptor 4 gene expressions in diarrhea-predominant irritable bowel syndrome patients]

Based on high throughput sequencing and PCR detection technology, this study has found out that intestinal microbial diversity was impaired and the quantities of two main bacteria flora (Bacteroidetes and Clostridium) were significantly reduced in patients with diarrhea-predominant irritable bowel syndrome (D-IBS). Meanwhile mucosal expression of toll-like receptor (TLR) 2 and TLR4 were significantly enhanced, which was inversely correlated with the reduction of Bacteroidetes and Clostridium. Thus, it suggests that D-IBS may be associated with TLR signal transduction triggered by the intestinal dysbacteriosis.

New advances in clinical application of fecal microbiota transplantation

The intestinal microbiota is composed of hundreds of millions of microorganisms and plays an important role in maintaining the body's immune function and resisting invasion of pathogenic microorganisms. Intestinal microecological imbalance can cause a variety of external and parenteral diseases. In recent years, fecal microbiota transplantation has achieved good effects in treating those diseases that are caused by Clostridium difficile infection. The therapy can correct intestinal microenvironment disorders, which makes it possible to use the therapy to treat other related diseases caused by microecological imbalance and improve human health. This paper will review recent advances in fecal microbiota transplantation in terms of its history, methods, application in external and parenteral diseases, and adverse reactions.

[Discrimination of alleles in HLA-C*04:01:01G groups]

The aim of this study was to investigate the relatively frequencies of alleles in the HLA-C*04:01:01G group and to analyze their relations with HLA-A and -B loci. DNA samples previously typed as HLA-C*04:01:01G were sequentially selected. The sequences for exon 2 to 7 of the HLA-C locus were analyzed by polymerase chain reaction sequence-based typing(PCR-SBT). The HLA-A, -B, -DRB1 and -DQB1 loci were genotyped using PCR-SBT method. The results showed that 178 samples (94.2%) and 11 samples (5.8%) were assigned as HLA-C*04:01:01 and HLA-C*04:82 respectively among 189 samples previously typed as HLA-C*04:01:01G. 72 haplotypes associated with HLA-C*04:01:01 and C*04:82 were found, in which the frequencies of 26 haplotypes were over 0.0050. HLA-C*04:01:01 was strongly related with A*02:03, A*02:07, A*11:01, A*33:03, B*13:01, B*15:01, B*15:05, B*15:27, B*40:01, B*54:01 alleles, while HLA-C*04:82 was related with B*40:01. It is concluded that HLA-C*04:01:01 and HLA-C*04:82 alleles were confirmed in the HLA-C*04:01:01G group, which should be discriminated by the routine HLA genotyping.

Effect of pH on the complexation of kaempferol-4'-glucoside with three β-cyclodextrin derivatives: isothermal titration calorimetry and spectroscopy study

The utilization of kaempferol and its glycosides in food and pharmaceutical industries could be improved by the formation of inclusion complexes with cyclodextrins at different pH. This study explores the complexation of kaempferol-4'-glucoside with sulfobutyl ether-β-cyclodextrin (SBE-β-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD), and methylated-β-cyclodextrin (M-β-CD) in phosphate buffer solutions of different pH using isothermal titration calorimetry, UV-vis absorption and proton nuclear magnetic resonance spectroscopy at 298.2 K. Experimental results showed that kaempferol-4'-glucoside binds with the three β- cyclodextrins in the same 1:1 stoichiometry. The rank order of stability constants is SBE-β-CD > HP-β-CD > M-β-CD at the same pH level and pH 6.0 > pH 7.4 > pH 9.0 for the same cyclodextrin. The binding of kaempferol-4'-glucoside with the three β-cyclodextrin derivatives is synergistically driven by enthalpy and entropy at pH 6.0 and enthalpy-driven at pH 7.4 and 9.0. The possible inclusion mode was that in the cavity of β-CD is included the planar benzopyranic-4-one part of the kaempferol-4'-glucoside.

[Effect of substrate temperature on structure and photoluminescence of ZnMgO films]

ZnMgO films were deposited on quartz glass substrates by the ultrasonic spray pyrolysis at different substrate temperatures (450-550 degrees C). The structural, surface morphological and optical properties of the samples were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence (PL) spectroscopy. The results demonstrate that the substrate temperature has important effect on structural and optical characteristics. All the films have hexagonal wurtzite polycrystalline structures and the c-axis preferential orientation has an optimum temperature of 530 degrees C. The sample prepared at this temperature owns uniform grain size, smooth surface morphology and better crystalline quality. The width of deep-level emission decreases and the near band edge (NBE) ultraviolet emission peak appears with the increase in temperature by the PL spectrum. When the temperature arrives to 530 degrees C, a distinct NBE emission peak can be observed at 374. 5 nm, while the deep level emission is almost undetectable.

Extended expression of B-class MADS-box genes in the paleoherb Asarum caudigerum

Asarum caudigerum (Aristolochiaceae) is a paleoherb species that is important for research in origin and evolution of angiosperm flowers due to its basal position in the angiosperm phylogeny. In this study, a subtracted floral cDNA library from floral buds of A. caudigerum was constructed and cDNA arrays by suppression subtractive hybridization were generated. cDNAs of floral buds at different stages before flower opening and of leaves at the seedling stage were used. The macroarray analyses of expression profiles of isolated floral genes showed that 157 genes out of the 612 unique ESTs tested revealed higher transcript abundance in the floral buds and uppermost leaves. Among them, 78 genes were determined to be differentially expressed in the perianth, 62 in the stamens, and 100 genes in the carpels. Quantitative real-time PCR of selected genes validated the macroarray results. Remarkably, APETALA3 (AP3) B-class genes isolated from A. caudigerum were upregulated in the perianth, stamens and carpels, implying that the expression domain of B-class genes in this basal angiosperm was broader than those in their eudicot counterparts.

[A clinical study of chromosome translocations in extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue in Chinese patients]

OBJECTIVE

To investigate the genetic aberrations in extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphomas from different sites of the body in Chinese patients.

METHODS

Two hundred and seventeen paraffin-embedded MALT lymphoma specimens from 11 major sites were studied with interphase fluorescence in situ hybridization (FISH) to detect t (11; 18) (q21; q21)/API2-MALT1, t (1; 14) (p22; q32)/IGH-BCL10, (14; 18) (q32; q21)/IGH-MALT1 and BCL6 gene involved chromosome translocations.

RESULTS

These translocations were mutually exclusive and detected in 21% (46/217) of the cases, including t (11; 18) (q21; q21) API2-MALT1 13% (29/217), t (1; 14) (p22; q32) IGH-BCL10 in 1% (3/217), t (14; 18) (q32; q21) IGH-MALT1 1% (2/217), BCL6 involved translocation in 2% (4/217) and IGH-unknown translocation partner in 4% (8/217). t (11; 18) (q21; q21) API2-MALT1 was found with the highest frequency in MALT lymphoma from lungs (47%, 8/17) and small intestine (29%, 4/14), followed by salivary gland (17%, 1/6), stomach (14%, 12/84) and ocular adnexae (6%, 4/68). t (1; 14) (p22; q32) was only detected in lungs (12%, 2/17) and stomach (1%, 1/84). t (14; 18) (q32; q21) was mainly detected in lungs (6%, 1/17) and ocular adnexae (2%, 1/68). BCL6 gene involved translocation was detected in salivary gland (17%, 1/6) and stomach (4%, 3/84).

CONCLUSIONS

It is demonstrated that the four translocations occur with markedly variable frequencies in MALT lymphoma of different sites in Chinese patients. The distributions of these chromosome translocations in Chinese patients are slightly different from those reported in western patients.

[Primary ocular adnexal lymphoproliferative lesions: clinicopathologic features and genetic alterations]

OBJECTIVE

To investigate clinicopathological and genetic characteristics of primary ocular adnexal lymphoproliferative lesions.

METHODS

Clinical, morphological and immunohistochemical features of 37 archival cases of primary ocular adnexal lymphoproliferative lesions were studied including 5 cases of reactive lymphoid hyperplasia and 32 lymphomas retrospectively. Classification of the lymphomas were made according to the WHO classification of tumors of haematopoietic and lymphoid tissues. All cases were studied by interphase fluorescence in situ hybridization (FISH) using dual color break apart probes of IgH, MALT1, bcl-6, c-Myc, bcl-2, CCND1, bcl-10, and FOXP1 for detection of chromosomal aberrations involving IgH, MALT1, bcl-6, c-Myc, bcl-2, cyclinD1, bcl-10 and FOXP1 genes, respectively. FISH with IgH / bcl-2 dual color dual fusion probe was used for detection of t(14;18)(q32;q21)/IgH-bcl-2. CEP18 spectrum orange probe was used for detection of aneuploidy of the chromosome 18.

RESULTS

Among 32 cases of lymphomas, 28 cases (87.5%) were extranodal marginal zone B-cell lymphomas of mucosa associated lymphoid tissue (MALT lymphoma), 2 cases were follicular lymphoma (FL) and 2 cases diffuse large B cell lymphoma (DLBCL). Among the 28 cases of MALT lymphoma, chromosomal aberrations were found in 60.7% (17/28) by interphase FISH analysis. One case showed positive IgH break-apart signal with unknown partner. 16 cases showed three copies of different genes, of which, three copies of MALT1, bcl-6, and c-Myc were identified in 7 cases (25%), 12 cases (43%), and 2 cases (8%) of MALT lymphomas, respectively. In addition, 5 cases showed two genes including three copies of bcl-6 and MALT1 in 4 cases, and three copies of bcl-6 together with c-Myc in one case. Furthermore, all cases with three copies of MALT1 had trisomy 18. t(14;18)(q32;q21) was detected in both follicular lymphomas. Of the 2 DLBCL cases, one showed three copies of bcl-6 together with trisomy 18 and the other one showed three copies of bcl-6 together with IgH and c-Myc rearrangements. Chromosomal aberration was not found in all 5 cases of reactive lymphoid hyperplasia.

CONCLUSIONS

The most common entity of primary ocular adnexal lymphomas is MALT lymphoma and FISH is helpful for their differential diagnosis and classification. Trisomy 18 and three copies of bcl-6 are common chromosomal aberrations in primary ocular adnexal MALT lymphomas.

[Studies on the chemical constituents of the essential oil of Artemisia dracunculus]

OBJECTIVE

To analyse the chemical constituents of Artemisia dracunculus.

METHOD

The essential oil from A. dracunculus was extracted by steam distillation and the chemical constituents were analysed by capillary GC-MS method. The relative content of each component was calculated by area normalization.

RESULT

36 peaks were separated and all of them were identified. The main chemical components were 3,7-dimethyl-1,3,7-octatriene (38.43%), 1S-alpha-pinene (36.96%), 1-methoxy-4-(2-Propenyl)-benzene (8.57%), limonene (6.33%), 1R-alpha-pinene (3.40%), etc.

CONCLUSION

The study provided solid and scientific proof for the further exploitation and utilization of A. dracunculus.