Comparative analysis of the gut microbiota of wild adult rats from nine district areas in Hainan, China

BACKGROUND

Wild rats have the potential to hold zoonotic infectious agents that can spread to humans and cause disease.

AIM

To better understand the composition of gut bacterial communities in rats is essential for preventing and treating such diseases. As a tropical island located in the south of China, Hainan province has abundant rat species. Here, we examined the gut bacterial composition in wild adult rats from Hainan province.

METHODS

Fresh fecal samples were collected from 162 wild adult rats, including three species (Rattus norvegicus, Leopoldamys edwardsi, and Rattus losea), from nine regions of Hainan province between 2017-2018.

RESULTS

We analyzed the composition of gut microbiota using the 16S rRNA gene amplicon sequencing. We identified 4903 bacterial operational taxonomic units (30 phyla, 175 families, and 498 genera), which vary between samples of different rat species in various habitats at various times of the year. In general, Firmicutes were the most abundant phyla, followed by Bacteroidetes (15.55%), Proteobacteria (6.13%), and Actinobacteria (4.02%). The genus Lactobacillus (20.08%), unidentified_Clostridiales (5.16%), Romboutsia (4.33%), unidentified_Ruminococcaceae (3.83%), Bacteroides (3.66%), Helicobacter (2.40%) and Streptococcus (2.37%) were dominant.

CONCLUSION

The composition and abundance of the gut microbial communities varied between rat species and locations. This work provides fundamental information to identify microbial communities useful for disease control in Hainan province.

[Increased receptor activator of nuclear factor kappa B ligand expressed on B10 cells in rheumatoid arthritis]

OBJECTIVE

To detect receptor activator of nuclear factor kappa B ligand (RANKL) expressed on B10 cells in rheumatoid arthritis (RA) and to evaluate the correlation between RANKL-producing B10 cells in RA and clinical features and laboratory parameters, trying to reveal the possible role of B10 cells in the pathogenesis of RA and the potential mechanism of impaired immunosuppressive capacities.

METHODS

25 RA patients and 20 healthy volunteers were enrolled. These RA patients did not received treatment with glucocorticoids, disease-modifying anti-rheumatic drug and biologics during the recent half of a year. The levels of RANKL-producing B10 cells were measured by flow cytometry (FCM) and polymerase chain reaction (PCR). The correlation between the frequencies of RANKL-producing B10 cells in RA and clinical data, laboratory parameters were analyzed. The role of tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) in inducing RANKL expression in B10 cells was evaluated by in vitro stimulation assay. Independent samples t test, Pearson and Spearman correlation were used for statistical analysis.

RESULTS

B10 cells were capable of producing RANKL at a low level in health controls. The frequencies of RANKL-producing B10 cells were markedly higher in RA patients than in health controls (3.65%±1.59% vs. 2.25%±0.68%, P<0.01). The frequencies of these cells correlated positively with RA tender joint counts, swollen joint counts and disease activity score in 28 joints (DAS28) (r=0.479, P=0.035; r=0.519, P=0.008; r=0.526, P=0.019). However, no correlation was found between these cells and RA patient age, disease duration, or the levels of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF) and anti-citrullinated peptide antibody (ACPA). After in vitro stimulation by TNF-α, but not IL-1β, B10 cells isolated from healthy donors demonstrated fundamentally upregulated expression of RANKL.

CONCLUSION

Our studies showed the frequencies of RANKL-producing B10 cells were markedly higher in RA patients, and their frequencies were positively correlated with RA tender joint counts, swollen joint counts and DAS28. These findings suggested that B10 cells might be involved in RA bone destruction.

[Clinical characteristics and prognosis of long-term glucocorticoid users with community-acquired pneumonia]

Objective: To explore the clinical features, etiological features and prognostic risk factors of long-term glucocorticoid users with community-acquired pneumonia (CAP). Methods: A retrospective study included 100 long-term glucocorticoid users with CAP (G-CAP group) from 11 hospitals of China between January 2014 and December 2014, while 100 non-immunocompromised patients with community-acquired pneumonia were enrolled as controls (nICH-CAP group). Characteristics including age, gender, underlying diseases, corticosteroids, symptoms, disease severity, imaging manifestations, etiology, respiratory failure, mechanical ventilation, whether the application of vasoactive drugs, antibiotics application, hospital mortality rate between the two groups were compared, and the prognostic factors of G-CAP were investigated using Logistic regression. Results: The peripheral blood lymphocytes[1.06(0.70, 1.68) vs 1.44 (0.87, 1.98)]in G-CAP group was less than nICH-CAP group (P<0.05). CT with pulmonary interstitial change (28.6% vs 9.9%), the proportion of patients with respiratory failure (25.0% vs 7.0%), mechanical ventilation (9.0% vs 2.0%), noninvasive mechanical ventilation (12.0% vs 2.0%), septic shock (9.0% vs 2.0%), and the hospital mortality rate (13.0% vs 3.0%) in G-CAP group were significantly higher than in nICH-CAP group (all P<0.05). Bacterial infection accounted for the highest proportion of infection (61.3%) in G-CAP group, but also virus infection (19.4%) and mixed infection (16.1%). Pseudomonas accounted for the highest proportion (47.4%) in bacterial infection of G-CAP. Logistic regression analysis showed that peripheral blood lymphocytes (OR=0.004, 95% CI: 0.000-0.234; P<0.05) and respiratory failure (OR=17.766, 95% CI: 4.933-131.0; P<0.05) were independent predictors of death in G-CAP group. Conclusions: The proportion of severe pneumonia and the mortality rate of patients with G-CAP are higher than the patients with nICH-CAP. Lymphopenia and respiratory failure are associated with poor outcome of patients with G-CAP.

[Clinicopathologic and molecular features of cribriform morular variant of papillary thyroid carcinoma]

Objective: To investigate the clinicopathologic and molecular features of the rare cribriform morular variant of papillary thyroid carcinoma (CMV-PTC). Methods: The clinicopathologic data of 10 patients with CMV-PTC were retrospectively reviewed. Immunohistochemical (IHC) staining was done using LSAB method. DNA sequencing for APC were applied using Sanger method. BRAF V600E mutation was examined using ARMS method. The cytological, morphological, IHC and molecular features were analyzed. Results: All patients were female at an average age of 27 years old. The tumors were mostly located in the right lobe of thyroid. Fine needle aspiration cytology was performed in three patients; two were diagnosed as suspicious for PTC and one as PTC. Nine tumors presented as solitary nodule and two as multiple nodules in both lobes. Infiltration was demonstrated in three cases. The average size was 2.6 cm. The neoplastic cells were arranged in papillary, cribriform, solid and glandular patterns, with rare or without colloid inside the lumen. The number of morula varied, ranging from zero to many. The neoplastic cells were variably enlarged, showing round, oval or spindle shape. Nuclear irregularity was identified as irregular membrane, nuclear grooves or pseudoinclusion, but no typical ground glass feature. Peculiar nuclear clearing could be observed in the morular cells. IHC staining showed the neoplastic cells were negative for thyroglobulin and p63, but positive for TTF1, cytokeratin 19 and estrogen receptor. Diffuse staining with cytokeratin was seen in the neoplastic cells and the morula. Specific cytoplasmic and nuclear staining of β-catenin was seen in the neoplastic cells but not the morula. Ki-67 proliferation index was 1%-30%. No recurrence or metastasis was observed. One patient was demonstrated to harbor both somatic and germline mutations of the APC gene, who was found to have adenomatous polyposis and her mother died of colonic carcinoma. No BRAF V600E mutation was detected. Conclusions: CMV-PTC is rare and shows atypical cytological and clinicopathological features, and it is easily misdiagnosed.TG, TTF1, ER and β-catenin are specific IHC markers for CMV-PTC. The morula is negative for cytokeratin 19, in contrast to squamous metaplasia. Although CMV-PTC has indolent clinical behavior, a definite diagnosis is necessary to rule out the possibility of APC gene mutation and related extra-thyroidal neoplasm, such as FAP and Gardner syndrome.

[Clinicopathologic characteristics of head and neck carcinoma showing thymus-like element]

Objective: To investigate clinicopathological features of carcinoma showing thymus-like elements (CASTLE) in the head and neck regions. Methods: Clinicopathological data of 7 patients with CASTLE in the head and neck regions were retrospectively reviewed.Immunohistochemical staining and in situ hybridization for EBER were performed. BRAF(V600E) mutation was examined by ARMS method in 6 cases. Results: There were 5 females and 2 males with age between 49 and 78 years (average of 65.6 years). All tumors were solitary nodular lesions with an infiltrative border, including 6 intrathyroid tumors and 1 extrathyroid tumor in the laryngeal pharynx.The tumors were 1.7-4.1 cm in diameter (average of 3.0 cm). Four cases demonstrated lymph node metastasis.All patients were alive without metastasis during follow-up, except one consultation case (with FNA sample) developed recurrence at the primary site. The cases showed different immunoreaction to CD5, diffuse immunoreaction with p63, CK5/6 and CD117, but negative staining for TTF1, TG and calcitonin. One case showed positive immunoreaction with Synin less than 30% tumor cells. The Ki-67 labeling index was between 3% and 90%. No BRAF(V600E) mutation and EB virus infection were detected. Conclusions: Extrathyroid CASTLE involving laryngeal pharynx shows the similar morphological and immunohistochemical features with intrathyroid CASTLE.Immunohistochemical markers of CD5 and CD117 are helpful in the diagnosis. Ki-67 labeling index can be high in CASTLE, especially in lymphoepithelioma type. CD5-negative CASTLE may have neuroendocrine differentiation. BRAF(V600E) mutation and EB virus may not be involved in the carcinogenesis of CASTLE.

Influence of the basal core promoter and precore mutation on replication of hepatitis B virus and antiviral susceptibility of different genotypes

Mutations in the basal core promoter (BCP) and precore (PC) regions of the hepatitis B virus (HBV) are more common in genotypes B and C than in genotype A, suggesting that these mutations might affect replication competency depending on genotype. The purpose of the study was to investigate the influence of these mutations on the capacity of HBV for replication and antiviral drug susceptibility according to genotype. Genotypes A, B, and C of HBV strains with a BCP mutation, PC mutation, or BCP + PC mutation were made by site-directed mutagenesis. Replication competency of each construct and susceptibility to nucleos(t) ide analogues were tested in an Huh7 cell line. In genotype A, the BCP and BCP + PC mutations increased the viral replication around 6.5 times compared with the wild type, and the PC mutation alone similarly increased the viral replication around three times. In genotypes B and C, all three mutant types increased viral replication to a similar extent, regardless of mutation pattern. Interestingly, the BCP mutation appeared to have a greater effect on viral replication in genotype A than in genotypes B and C. This finding was unexpected because the BCP mutation is more common in HBV genotypes B and C. Moreover, the BCP, PC, and BCP + PC mutations decreased the sensitivity of HBV to antiviral agents to various degrees (2- to 10-fold) regardless of genotype. In conclusion, BCP and PC mutations increased viral replication regardless of HBV genotype and decreased in vitro antiviral susceptibility to the nucleos(t) ide analogues.

Different mechanism of selection of adefovir-resistant mutant viruses during adefovir monotherapy in patients with lamivudine-resistant chronic hepatitis B

BACKGROUND

Adefovir (ADV) resistance is more frequent in lamivudine (LMV)-resistant chronic hepatitis B (CHB) patients than in nucleos(t)ide analogue-naïve patients. The majority of LMV-resistant mutants harbor the rtM204V/I mutation, while a minor fraction harbor the rtA181V/T mutation. We aimed to elucidate the mechanism of the high rate of ADV resistance in LMV-resistant patients during ADV therapy.

METHODS

We performed a clonal analysis of HBV reverse transcriptase in treatment-naïve (n = 3) and LMV-resistant patients before ADV therapy (n = 14). Dynamic changes in the viral population (n = 9) during ADV therapy were also analyzed.

RESULTS

Before ADV therapy, rtA181V/T was observed in 30 of 680 clones (4.4%) from 7 patients with LMV resistance under dominant rt204V/I mutation and in one of 150 clones in treatment-naïve patients. The rtA181V/T mutation was more frequently found in clones from LMV-resistant patients than in treatment-naïve patients (p = 0.029). The rtN236T mutation was not observed in any clone. During ADV therapy, most rtM204V/I mutants were replaced by wild type in all 3 patients without the rtA181V/T mutation and in one patient with the rtA181V/T mutation. Subsequently, wild type was replaced by the rtN236T and/or rtA181V/T mutant. In patients with the rtA181V/T mutation (n = 6), the rtA181V/T mutant overtook the rtM204V/I mutant in 3 of 4 patients with ADV resistance. In 2 patients without ADV resistance, most of the viral population was replaced by wild type by the last follow-up.

CONCLUSION

The high rate of ADV resistance in patients with LMV-resistance might be attributable to preexisting rtA181V/T mutant virus.

The ZmCLA4 gene in the qLA4-1 QTL controls leaf angle in maize (Zea mays L.)

Maize architecture is a major contributing factor to their high level of productivity. Maize varieties with an erect-leaf-angle (LA) phenotype, which increases light harvesting for photosynthesis and grain-filling, have elevated grain yields. Although a large body of information is available on the map positions of quantitative trait loci (QTL) for LA, little is known about the molecular mechanism of these QTL. In this study, the ZmCLA4 gene, which is responsible for the qLA4-1 QTL associated with LA, was identified and isolated by fine mapping and positional cloning. The ZmCLA4 gene is an orthologue of LAZY1 in rice and Arabidopsis. Sequence analysis revealed two SNPs and two indel sites in ZmCLA4 between the D132 and D132-NIL inbred maize lines. Association analysis showed that C/T/mutation667 and CA/indel965 were strongly associated with LA. Subcellular localization verified the functions of a predicted transmembrane domain and a nuclear localization signal in ZmCLA4. Transgenic maize plants with a down-regulated ZmCLA4 RNAi construct and transgenic rice plants over-expressing ZmCLA4 confirmed that the ZmCLA4 gene located in the qLA4 QTL regulated LA. The allelic variants of ZmCLA4 in the D132 and D132-NIL lines exhibited significant differences in leaf angle. ZmCLA4 transcript accumulation was higher in D132-NIL than in D132 during all the developmental stages and was negatively correlated with LA. The gravitropic response was increased and cell shape and number at the leaf and stem junctions were altered in D132-NIL relative to D132. These findings suggest that ZmCLA4 plays a negative role in the control of maize LA through the alteration of mRNA accumulation, leading to altered shoot gravitropism and cell development. The cloning of the gene responsible for the qLA4-1 QTL provides information on the molecular mechanisms of LA in maize and an opportunity for the improvement of plant architecture with regard to LA through maize breeding.

Chronic blockade of the angiotensin II receptor has a differential effect on adipose and vascular PAI-1 in OLETF rats

Angiotensinogen (AGT) and plasminogen activator inhibitor-1 (PAI-1) are expressed in both vascular and adipose tissues. Angiotensin II (AG II) has an adipogenic effect and increases PAI-1 expression. To evaluate the chronic effects of AG II type 1 receptor (AT(1)R) antagonism on adipose mass and PAI-1 expression in vascular and adipose tissues, losartan (30mg/kg/day) was administered to Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of type 2 diabetes, for 20 weeks. Adipose mass and regional fat distribution in the abdomen did not change after chronic AT(1)R antagonism in OLETF rats. AGT and PAI-1 mRNA expressions in adipose tissue of OLETF rats were significantly increased compared with Long-Evans Tokushima Otsuka (LETO) rats, the normal control. Chronic losartan therapy further increased the level of adipose AGT in OLETF rats, but did not affect the level of adipose PAI-1 mRNA. In contrast, aortic PAI-1 expression in OLETF rats was attenuated by chronic losartan therapy. Our results have two implications. First, adipose tissue may be an important source of AG II in metabolic syndrome even after chronic losartan therapy. Second, chronic AT(1)R antagonism with losartan causes differential effects on vascular and adipose PAI-1 expression.

Does depression generate negative life events?

This prospective study investigated whether major depressive disorder can cause negative life events. One hundred and thirteen normal college men have been followed biennially from age 26 until age 62. Fourteen major negative life events were assessed retrospectively by a self-report checklist. A blind rater read each man's complete records over the 35 years and used the same checklist prospectively. The negative life events were divided into dependent and independent groups according to whether the men's own behavior could have played a role in causing the events. In comparison with the normal control group, depressed individuals had a higher density of dependent negative life events after their first episode of depression. This difference did not exist for the occurrence of independent negative life events. Independent negative life events tended to be related to help seeking behaviors rather than to depression. This study confirmed our hypothesis that affective spectrum disorder can generate self-induced negative life events, which may contribute to the chronicity of the disorder.

Antecedents and consequences of negative life events in adulthood: a longitudinal study

OBJECTIVE

This study investigated whether negative life events affected subjects' long-term physical and mental health.

METHOD

One hundred thirteen normal college men completed biennial follow-up questionnaires from age 26 until age 62. At age 62 they retrospectively assessed 16 major negative life events with a self-report checklist. A blind rater read each man's complete records over the 35 years and completed the same checklist prospectively. The men had independent physical examinations at age 65.

RESULTS

It was demonstrated that negative life events affect men's psychological health more than their physical health. The correlation of negative life events with physical health was so low that no significant relationship between the two variables could be established. Negative life events were significantly associated with affective spectrum disorder and its relevant indicators. Further, the Cox proportional hazards model revealed that negative life events, family history of depression, and psychosocial stability during the college years were independent and statistically significant predictors of depression.

CONCLUSIONS

This study supports the widely held belief that biological factors (heredity), psychological factors (unstable personality), and social factors (negative life events) are all etiologically related to depression.

[Primary hepatosarcoma: reports of 8 cases]

Eight cases of the primary hepatosarcoma were reported in this paper. These cases were verified by resection and pathological examination. The abdominal pain and mass were of the main clinical features. The image studies showed the occupied lesions of the liver. The preoperative differential diagnosis is of difficulty. All these cases were misdiagnosed: 6 cases (75%) as cystic lesions and 2 cases (25%) as cancer of the liver, The sarcoma of the liver is usually huge and central necrotized which formed liquid-cavity. Therefore the differential diagnosis of huge mixed cystic lesions of the liver should be stressed. During operation, the frozen section pathological examination should be performed as a routine in case misdiagnosis and mistreatment happen. Early surgical resection is suggested in order to raise the survival rate.