Tenofovir disoproxil fumarate mediates neuronal injury by inducing neurotoxicity

PURPOSE

Highly active antiretroviral therapy (HAART) is an accepted treatment option for patients with virus infection. Mounting evidence indicated that persistent HAART treatment is implicated with increased morbidity of HIV-associated neurocognitive disorders (HAND) in patients. Tenofovir disoproxil fumarate (TDF), a novel nucleotide reverse transcriptase inhibitor (NRTI), was used in patients with HIV co-infected with HBV. And it is still a vital first-line antiretroviral compounds in HAART. However, whether persistent treatment with TDF is involved in HAND development remains to be further elucidated. In this study, we aimed to discuss the neurotoxicity of TDF.

METHODS

We used SH-SY5Y cells and primary neuronal cells to evaluate the neurotoxicity of TDF in vitro. The cytotoxicity of TDF on SH-SY5Y cells and primary neuronal cells was evaluated by the cell viability and LDH levels by MTT assay and LDH kit, respectively. Hoechst 33342 staining, TUNEL assay and flow cytometry were performed to evaluate the cells apoptosis. The intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) production were measured by commercial kits. In addition, the activation level of caspase-3 was evaluated using spectrophotometry and western blotting.

RESULTS

Our results showed that TDF treatment significantly induced cell viability and induced apoptosis of SH-SY5Y cells and primary neuronal cells. Furthermore, the ROS levels and MDA productions were significantly up-regulated in nerve cells treated with TDF.  CONCLUSION: Our findings indicated that TDF may induce neuronal cell apoptosis through increasing the intracellular ROS and the expression level of caspase-3, which may be related to the increasing prevalence of HAND.

Cathelicidin LL-37 improves bone metabolic balance in rats with ovariectomy-induced osteoporosis via the Wnt/beta-catenin pathway

Osteoporosis is a bone disease characterized by low bone mineral density (BMD) and impaired bone microarchitecture due to the abnormal activity of osteoclasts. Cathelicidins are antimicrobial peptides present in the lysosomes of macrophages and polymorphonuclear leukocytes. LL-37, a cathelicidin, induces various biological effects, including modulation of the immune system, angiogenesis, wound healing, cancer growth, as well as inflammation, and bone loss. A previous study reported direct involvement of LL-37 suppressing osteoclastogenesis in humans. Here, we examined the role of LL-37 in the treatment of osteoporosis using an ovariectomy (OVX) rat model. Our results showed that LL-37 significantly reduced bone loss and pathological injury in OVX rats with osteoporosis. Furthermore, we found that LL-37 significantly increased the activity of the Wnt/beta-catenin pathway in OVX rats with osteoporosis, including the increased expression of beta-catenin, Osterix (Osx), and Runt-related transcription factor 2 (Runx2), whereas XAV-939, an inhibitor of the Wnt/beta-catenin pathway, significantly blocked the effects of LL-37 on bone loss and abnormal bone metabolism. Altogether, our findings suggested that LL-37 exerted a protective role in regulating bone loss and abnormal bone metabolism in rats with osteoporosis by activating the Wnt/beta-catenin pathway.

Increased Drp1 promotes autophagy and ESCC progression by mtDNA stress mediated cGAS-STING pathway

Background

Mitochondrial dynamics homeostasis is important for cell metabolism, growth, proliferation, and immune responses. The critical GTPase for mitochondrial fission, Drp1 is frequently upregulated in many cancers and is closely implicated in tumorigenesis. However, the mechanism underling Drp1 to influence tumor progression is largely unknown, especially in esophageal squamous cell carcinoma (ESCC).

Methods

Immunohistochemistry was used to examine Drp1 and LC3B expression in tissues of ESCC patients. Autophagic vesicles were investigated by transmission electron microscopy. Fluorescent LC3B puncta and mitochondrial nucleoid were observed by fluorescent and confocal microscopy. Mitochondrial function was evaluated by mitochondrial membrane potential, ROS and ATP levels. Xenograft tumor model was performed in BALB/c nude mice to analyze the role of Drp1 on ESCC progression.

Results

We found that Drp1 high expression is correlated with poor overall survival of ESCC patients. Drp1 overexpression promotes cell proliferation and xenograft ESCC tumor growth by triggering autophagy. Furthermore, we demonstrated that Drp1 overexpression disturbs mitochondrial function and subsequent induces mitochondrial DNA (mtDNA) released into the cytosol thereby inducing cytosolic mtDNA stress. Mechanistically, cytosolic mtDNA activates the cGAS-STING pathway and facilitates autophagy, which promotes ESCC cancer growth. Moreover, mtDNA digestion with DNase I and autophagy inhibition with chloroquine attenuates the cGAS-STING pathway activation and ESCC cancer growth.

Conclusions

Our finding reveals that Drp1 overexpression induces mitochondrial dysfunction and cytosolic mtDNA stress, which subsequently activates the cGAS-STING pathway, triggers autophagy and promotes ESCC progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02262-z.

Ivermectin induces apoptosis of esophageal squamous cell carcinoma via mitochondrial pathway

Background

Esophageal squamous cell carcinoma (ESCC) is the most predominant primary malignant tumor among worldwide, especially in China. To date, the successful treatment remains a mainly clinical challenge, it is imperative to develop successful therapeutic agents.

Methods

The anti-proliferative effect of ivermectin on ESCC is investigated in cell model and in nude mice model. Cell apoptosis was assessed using flow cytometry, TUNEL assay and western blotting. Mitochondrial dysfunction was determined by reactive oxygen species accumulation, mitochondrial membrane potential and ATP levels.

Results

Our results determined that ivermectin significantly inhibited the proliferation of ESCC cells in vitro and in vivo. Furthermore, we found that ivermectin markedly mediated mitochondrial dysfunction and induced apoptosis of ESCC cells, which indicated the anti-proliferative effect of ivermectin on ESCC cells was implicated in mitochondrial apoptotic pathway. Mechanistically, ivermectin significantly triggered ROS accumulation and inhibited the activation of NF-κB signaling pathway and increased the ratio of Bax/Bcl-2.

Conclusions

These finding indicated that ivermectin has significant anti-tumour potential for ESSC and may be a potential therapeutic candidate against ESCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-09021-x.

Characterization of fragment sizes, copy number aberrations and 4-mer end motifs in cell-free DNA of hepatocellular carcinoma for enhanced liquid biopsy-based cancer detection

Circulating cell‐free DNA (cfDNA) fragmentomics, which encompasses the measurement of cfDNA length and short nucleotide motifs at the ends of cfDNA molecules, is an emerging field for cancer diagnosis. The utilization of cfDNA fragmentomics for the diagnosis of patients with hepatocellular carcinoma (HCC) caused by hepatitis B virus (HBV) is currently limited. In this study, we utilized whole‐genome sequencing data of cfDNA in samples from patients with HCC (n = 197) and HBV (n = 187) to analyze the association of fragment size selection (< 150 bp) with tumor fraction (TF), copy number variation (CNV) alterations and the change in the proportion of 4‐mer end motifs in HCC and HBV samples. Our analyses identified five typical CNV markers (i.e. loss in chr1p, chr4q and chr8p, and gain in chr1q and chr8q) in cfDNA with a cumulatively positive rate of ˜ 95% in HCC samples. Size selection (< 150 bp) significantly enhanced TF and CNV signals in HCC samples. Additionally, three 4‐mer end motifs (CCCA, CCTG and CCAG) were identified as preferred end motifs in HCC samples. We identified 139 end motifs significantly associated with fragment size that showed similar patterns of associations between patients with HCC and HBV, suggesting that end motifs might be inherently coupled with fragment size by a ubiquitous mechanism. Here we conclude that CNV markers, fragment size selection and end‐motif pattern in cfDNA have potential for effective detection of patients with HCC.

Correlations of CYP11B2 gene polymorphisms with eclampsia

OBJECTIVE

The aim of this study was to explore the relationship between CYP11B2 gene polymorphisms and eclampsia.

PATIENTS AND METHODS

A total of 400 pregnant women treated in our hospital were enrolled in this study, including 200 normal pregnant women (pregnancy group) and 200 pregnant women with eclampsia (eclampsia group). Peripheral blood was collected from subjects of the two groups. Subsequently, genomic deoxyribonucleic acids (DNAs) were extracted and amplified via polymerase chain reaction (PCR) for detection of CYP11B2 rs4543, rs3802228 and rs104894072 polymorphisms. The expression level of CYP11B2 gene was measured as well. Additionally, the correlations of CYP11B2 gene polymorphisms with blood pressure and coagulation and renal function indexes were analyzed.

RESULTS

The distribution of alleles of rs4543 locus in CYP11B2 gene was significantly different between eclampsia group and pregnancy group (p=0.027). The frequency of the allele C was significantly lower in eclampsia group than that of pregnancy group (p<0.05). There was a statistically significant difference in the genotype distribution of CYP11B2 rs3802228 (p=0.000) and rs104894072 (p=0.000) between eclampsia group and pregnancy group (p<0.05). Meanwhile, the frequency of AA genotype of rs3802228 and TG genotype of rs104894072 was remarkably higher in eclampsia group than that in pregnancy group (p<0.05). The distribution of the locus rs104894072 (p=0.044) in dominant model and rs3802228 (p=0.002) in recessive model in eclampsia group was different from that in pregnancy group (p<0.05). Eclampsia group showed remarkably elevated frequency of TT + TG of the locus rs104894072 in dominant model and lowered frequency of AG + GG of the locus rs3802228 in recessive model (p<0.05). Similarly, a significant difference was observed in the distribution of the haplotypes CGG (p=0.001) and TGT (p=0.048) in CYP11B2 gene between eclampsia group and pregnancy group (p<0.05). The linkage disequilibrium of the loci rs3802228 and rs104894072 was relatively high (D'=0.382). The polymorphism of the locus rs104894072 in CYP11B2 gene had an evident relation to CYP11B2 gene expression (p<0.05). Meanwhile, the expression of CYP11B2 gene was markedly higher in patients with GG genotype in eclampsia group (p<0.05). The polymorphism of CYP11B2 rs4543 was notably associated with PT level of patients in eclampsia group (p=0.000). Conversely, rs3802228 polymorphism was correlated with 24 h urine protein level (p=0.000). Besides, the proportion of patients with CGG haplotype was significantly larger among patients with systolic blood pressure of 140-160 mmHg (p<0.05). In addition, the proportion of patients with TGT haplotype was evidently greater among patients with systolic blood pressure >180 mmHg in eclampsia group (p<0.05).

CONCLUSIONS

CYP11B2 gene polymorphisms are significantly correlated with the development and progression of eclampsia.

Changes in intestinal flora in preeclampsia rats and effects of probiotics on their inflammation and blood pressure

OBJECTIVE

The aim of this study was to investigate the changes in intestinal flora in preeclampsia rats and the effects of probiotics on their inflammation and blood pressure.

MATERIALS AND METHODS

A total of 40 Specific Pathogen Free (SPF) Wistar rats were randomly selected in this study. Abdominal operation was performed to reduce uterine blood perfusion, so as to establish the model of preeclampsia in rats. All rats were randomly divided into two groups, namely, observation group (treated with probiotics, n=20) and control group (not treated with probiotics, n=20). Subsequently, the changes in serum endotoxin level during intervention, the 24-h urinary 99mTc-diethylene triamine pentaacetic acid (DTPA) excretion rate, and intestinal flora colonization ability after intervention were compared between the two groups. The distribution of intestinal flora after intervention was recorded in the two groups. Meanwhile, vascular endothelial function and blood pressure following intervention were compared between the two groups as well. In addition, the changing trend of inflammatory cytokines during intervention in the two groups, and the correlation of colonization ability of intestinal flora with changes in systolic blood pressure and high-sensitivity C-reactive protein (hs-CRP) level in patients were analyzed.

RESULTS

At 3 days and 1 week after intervention, serum endotoxin level in the observation group was significantly lower than that in the control group at the same period (p<0.05). Following intervention, observation group exhibited remarkably higher excretion rate of 24-h urinary 99mTc-DTPA (p<0.05), stronger colonization ability of intestinal flora (p<0.05), higher levels of Bifidobacteria and Lactobacillus in intestinal flora (p<0.05), lower level of endothelin-1 (ET-1) (p<0.05) and higher level of nitric oxide (NO) (p<0.05) than the control group. In addition, the systolic blood pressure and diastolic blood pressure in the observation group were basically normal, which were both notably lower than those in the control group (p<0.05). At 3 days and 1 week after intervention, the levels of serum inflammatory cytokine hs-CRP in the observation group was markedly lower than that in the control group (p<0.05) at the same period. Furthermore, the colonization ability of intestinal flora was negatively associated with the changes in systolic blood pressure and hs-CRP level in patients (p<0.05).

CONCLUSIONS

Treating preeclampsia rats with probiotics can effectively reduce the level of serum endotoxin, improve the body's capacity to eliminate metabolites and the colonization ability of intestinal flora, maintain the stability of intestinal flora, enhance vascular endothelial function, and reduce blood pressure and the body's inflammatory responses.

Effect of lncRNA-BLACAT1 on drug resistance of non-small cell lung cancer cells in DDP chemotherapy by regulating cyclin D1 expression

OBJECTIVE

The aim of this study was to investigate the effect of long non-coding ribonucleic acid (lncRNA)-bladder cancer associated transcript 1 (BLACAT1) on the drug resistance of non-small cell lung cancer (NSCLC) cells in cisplatin (DDP) chemotherapy by regulating the expression of Cyclin D1.

MATERIALS AND METHODS

The analysis of the lncRNA expression profiles in 483 cases of NSCLC tissues and 347 cases of cancer-adjacent tissues in Gene Expression Omnibus (GEO) database revealed that lncRNA-BLACAT1 was differentially expressed in NSCLC and related to prognosis. In order to further study its mechanism of action on DDP-resistant cells, the expression level of lncRNA-BLACAT1 in normal human lung bronchial epithelial cell line BEAS-2B, NSCLC cell line A549, and DDP-resistant cell line A549 (A549/DDP) was detected by quantitative Polymerase Chain Reaction (qPCR). LncRNA-BLACAT1 small interfering RNA (siRNA) (si-BLACAT1) and lncRNA-BLACAT1 negative control (si-NC) were transfected into A549/DPP cells. Then, qPCR was carried out to detect the changes in the expression of lncRNA-BLACAT1 before and after transfection. Thereafter, cell cycle and cell growth rate were detected by flow cytometry and the cell growth curve. Besides, the changes in cell migration, cell apoptosis, and Cyclin D1 were detected via wound healing assay, flow cytometry, and Western blotting (WB).

RESULTS

In GEO database, lncRNA-BLACAT1 was significantly overexpressed in NSCLC (p<0.05), and the prognosis of NSCLC in BLACAT1 low-expression group was better than that in the BLACAT1 high-expression group (p<0.0001). Compared with that in BEAS-2B cells, BLACAT messenger RNA (mRNA) was notably highly expressed in A549 cells (p<0.05), and compared with that in A549 cells, BLACAT1 mRNA in A549/DPP was significantly highly expressed in A549/DDP cells (p<0.05). Additionally, in comparison with that in the si-NC group, the content of lncRNA-BLACAT1 in si-BLACAT1 group was remarkably decreased (p<0.01). Moreover, flow cytometry detection of cell cycle revealed that compared with those in si-NC group, G0/G1 phase was markedly prolonged and S phase was shortened in si-BLACAT1 group. MTS assay manifested that the absorbance at 450 nm in si-BLACAT1 group was evidently decreased on the 3rd day compared with that in the si-NC group (p<0.05), and the difference between the two groups was the most significant on the 5th day (p<0.001). According to wound healing assay, compared with those in si-NC group, the distance between cells became larger, the cell migration ability was remarkably weakened (p<0.05), and cell apoptosis was prominently reduced in si-BLACAT1 group (p<0.05). WB results showed that compared with si-NC group, si-BLACAT1 group had significantly reduced Cyclin D1 (p<0.05) CONCLUSIONS: LncRNA-BLACAT1 regulates the expression of Cyclin D1, reduces the malignant phenotype of drug-resistant cells, and increases the sensitivity of lung cancer cells to DDP.

MiR-507 inhibits the growth and invasion of trophoblasts by targeting CAMK4

OBJECTIVE

To elucidate the potential influences of miR-507 and CAMK4 on the progression of preeclampsia (PE).

PATIENTS AND METHODS

Placental tissues were collected from 24 PE pregnancies and 24 healthy pregnancies. The relative levels of miR-507 and CAMK4 in placental tissues were detected. In addition, expressions of apoptosis-associated genes in collected tissues were examined by both quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). The influences of miR-507 and CAMK4 on proliferative and migratory abilities in HTR-8/SVneo cells were assessed by CCK-8 and transwell assay, respectively. The target relationship between miR-507 and CAMK4 was detected by Luciferase assay.

RESULTS

MiR-507 was upregulated in placental tissues collected from PE pregnancies. Overexpression of miR-507 suppressed proliferative and migratory abilities, and stimulated apoptosis in HTR-8/SVneo cells. CAMK4 was the target gene of miR-507, which was downregulated in placental tissues collected from PE pregnancies and negatively correlated to miR-507 level. The knockdown of CAMK4 suppressed proliferative and migratory abilities, and stimulated apoptosis in HTR-8/SVneo cells, and these trends were abolished by silence of miR-507.

CONCLUSIONS

Highly expressed miR-507 in PE pregnancies inhibits proliferative and migratory potentials, and induces apoptosis in trophoblasts by targeting CAMK4.

EphA3 promotes the proliferation of NPC cells through negatively regulating the ability of FOG2

OBJECTIVE

The purpose of this study was to investigate the expression level of EphA3 in nasopharyngeal carcinoma (NPC) and its effect on the proliferative capacity of NPC. Meanwhile, the underlying mechanism by which EphA3 prompts NPC malignant progression was further explored.

PATIENTS AND METHODS

In this study, the expression of EphA3 in 42 pairs of tumor tissue specimens and paracancerous ones collected from NPC patients was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), and the interplay between EphA3 expression and clinical indicators, as well as prognosis of NPC patients was analyzed. Meanwhile, qRT-PCR was also applied to further verify EphA expression in NPC cell lines. In addition, EphA knockdown model was constructed in NPC cell lines, CNE2, and 6-10B, and the impacts of EphA on NPC cell functions was assessed through Cell Counting Kit-8 (CCK-8), cell colony formation, as well as 5-Ethynyl-2'- deoxyuridine (EdU) assays. Finally, a potential interplay between EphA3 and FOG2 was also investigated.

RESULTS

In this study, qRT-PCR results revealed that EphA3 expression levels in tumor tissues of patients with NPC were markedly higher than those in adjacent tissues. Compared with patients with low expression of EphA3, those with highly expressed EphA3 had a more advanced pathological stage. In addition, in vitro experiments showed that knocking down EphA3 notably attenuated the proliferation capacity of NPC cells. Subsequently, it was found that the expression of FOG2 in NPC cells was remarkably decreased both in NPC cell lines and tissues, which had a negative correlation with EphA3. Finally, cell recovery experiment revealed a mutual regulation between EphA3 and FOG2, which then together affected the malignant progression of NPC.

CONCLUSIONS

EphA3 is significantly relevant to pathological staging and poor prognosis of patients with NPC and may enhance the proliferation ability of NPC cells by modulating FOG2.

Effects of lncRNA MEG3 on proliferation and apoptosis of gallbladder cancer cells through regulating NF-κB signaling pathway

OBJECTIVE

To explore the effects of long non-coding ribonucleic acid (lncRNA) maternally expressed gene 3 (MEG3) on proliferation and apoptosis of gallbladder cancer (GBC) cells and its molecular mechanism.

MATERIALS AND METHODS

The relative expression level of lncRNA MEG3 in GBC cell lines was detected via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). The lncRNA MEG3 expression plasmids were constructed, the cell proliferation ability was detected via Cell Counting Kit-8 (CCK-8) assay and colony formation assay, and the apoptosis was detected via flow cytometry. The effects of lncRNA MEG3 expression on endoplasmic reticulum stress (ERS)-related proteins were determined using Western blotting, and the changes in nuclear factor-κB (NF-κB) protein in the nucleus were determined after overexpression of lncRNA MEG3.

RESULTS

The expression of lncRNA MEG3 in three kinds of GBC cell lines was lower than that in human immortalized normal biliary epithelial cells (p<0.05). The results of CCK-8 assay and colony formation assay showed that overexpression of lncRNA MEG3 significantly reduced the proliferation rate and colony formation ability of GBC-SD cells compared with negative control (NC) group (p<0.05, p<0.05). According to the results of flow cytometry, the apoptosis rate was higher in lncRNA MEG63 overexpression group compared with that in NC group (p<0.05). Moreover, the ERS-related proteins (MANF, GRP78, and caspase-3) were remarkably upregulated in lncRNA MEG63 overexpression group compared with those in NC group, indicating that ERS is activated by lncRNA MEG63 overexpression. The NF-κB signal in GBC cells was activated by lncRNA MEG3.

CONCLUSIONS

LncRNA MEG3 activates the NF-κB signal in GBC cells to affect the proliferation and apoptosis of GBC cells.

Long non-coding RNA small nucleolar RNA host gene 7 facilitates the proliferation, migration, and invasion of esophageal cancer cells by regulating microRNA-625

Background

Esophageal cancer (EC) is a highly aggressive malignant tumor, of which esophageal squamous cell carcinoma (ESCC) constitutes the main subtype. Long non-coding RNA (lncRNA) small nucleolar RNA host gene 7 (SNHG7) has been extensively studied in many tumors and has been confirmed to be an oncogene; however, it has yet to be investigated in an ESCC study. Therefore, this study intended to uncover the role of SNHG7 in ESCC.

Methods

Quantitative real-time polymerase chain reaction was applied to measure the expression levels of SNHG7 and miR-625 in ESCC tumor tissues and cell lines. Cell Counting Kit-8 assay, 5-Ethynyl-2'-deoxyuridine assay, scratch assay, and Transwell assay were conducted to assess the proliferation, migration, and invasion ESCC cell. We verified the interaction between SNHG7 and miR-625 by performing the dual luciferase reporter gene experiment.

Results

Compared to that in adjacent normal tissues and HET1A cell lines, the expression level of SNHG7 in ESCC tumor tissues and ESCC cell lines was up-regulated, while the expression level of miR-625 was down-regulated. ESCC cell proliferation, migration, and invasion were significantly promoted by SNHG7 overexpression but inhibited by silencing of SNHG7. Further, luciferase reporter gene experiments confirmed that SNHG7 interacted with miR-625, and rescue experiments showed that SNHG7 promoted the malignant phenotype by inhibiting miR-625.

Conclusions

SNHG7 is up-regulated in ESCC tumor tissues and cell lines, while miR-625 is expressed at a low level. SNHG7 is able to facilitate the proliferation, migration, and invasion of ESCC cells by targeting miR-625.

TGF-β1 promotes pulmonary arterial hypertension in rats via activating RhoA/ROCK signaling pathway

OBJECTIVE

To investigate the influence of the Rho/Rho-associated kinase (ROCK) signaling pathway in rats with pulmonary arterial hypertension (PAH) under the intervention with transforming growth factor-beta 1 (TGF-β1).

MATERIALS AND METHODS

A total of 30 rats were divided into three groups using a random number table, including control group (healthy rats, n=10), model group (PAH rats, n=10), and TGF group (PAH rats injected with 5 ng/mL TGF-β1 recombinant protein, n=10). The systolic blood pressure, ventricular hypertrophy index, pathological changes in lung tissues, TGF-β1 level, protein, and messenger ribonucleic acid (mRNA) expressions of RhoA and ROCK, as well as concentrations of serum nitric oxide (NO) and endothelin-1 (ET-1) were detected via hemodynamics test, hematoxylin and eosin (HE) staining, immunohistochemical method, reverse transcription-polymerase chain reaction (RT-PCR), and enzyme-linked immunosorbent assay (ELISA).

RESULTS

The results of hemodynamics test showed that the right ventricular systolic pressure was increased markedly in model group (46.53±8.81) and TGF group (56.79±9.12) compared with that in control group (26.03±4.21) (p<0.05). The mean pulmonary systolic pressure in model group (25.89±1.92) and TGF group (29.41±1.91) was evidently higher than that in control group (15.77±2.71) (p<0.05). According to the results of heart weight measurement, model group (0.5118±0.1635) exhibited a higher ventricular hypertrophy index than control group (0.2908±0.0313) (p<0.05) but a lower ventricular hypertrophy index than TGF group (0.7231±0.1004) (p<0.05). The medial thickness of the pulmonary artery of the rats was observed through the HE staining. It was found that compared with control group, the medial thickness of the pulmonary artery was increased significantly in model group (p<0.05), while it was raised more prominently in TGF group, higher than that in model group, suggesting that TGF-β1 expression can increase the medial thickness of the pulmonary artery. It was manifested in immunohistochemical results that the protein expression of RhoA in the left lung tissues rose notably in model group compared with that in control group (p<0.05), and it was also raised remarkably in TGF group in comparison with that in model group (p<0.05), illustrating that the protein expression of TGF can activate the activity of RhoA and ROCK. The results of RT-PCR indicated that the mRNA expressions of RhoA and ROCK in the left lung tissues were elevated distinctly in model group and TGF group compared with those in control group (p<0.05), and the increases were more apparent in TGF group than those in model group (p<0.05). It was revealed in ELISA results that in comparison with control group, model group, and TGF group had markedly increased concentrations of serum NO and ET-1 (p<0.05), while the rises of serum NO and ET-1 concentrations in TGF group were the most prominent compared with those in model group (p<0.05).

CONCLUSIONS

Overexpressed TGF-β1 can activate the RhoA/ROCK signaling pathway, thus promoting the occurrence and development of PAH.

Linc00707 promotes cell proliferation, invasion, and migration via the miR-30c/CTHRC1 regulatory loop in breast cancer

OBJECTIVE

Breast cancer (BC) is the most common malignant tumor in women. We aimed at investigating the function of long non-coding RNA LINC00707 in BC and the potential mechanism.

PATIENTS AND METHODS

The expression level of linc00707 was determined using the quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) in BC tissues and cell lines. The Cell Counting Kit-8 (CCK-8) and colony formation assays were performed to detect the potential influence of LINC0070 on the proliferation ability of the BC cells. Also, the invasion and migration abilities were assessed by the transwell assay. Furthermore, with the bioinformatic analysis and the Dual-Luciferase Reporter Gene Assay, we analyzed the interaction in LINC00707/miR-30c/CTHRC1 regulatory loop. The regulatory effects of LINC00707/miR-30c/CTHRC1 on BC were finally determined.

RESULTS

LINC00707 was significantly upregulated in BC tissues and cell lines. The knockdown of LINC00707 inhibited proliferation, invasion, and migration in MDA-MB-231 cells, while the overexpression of LINC00707 achieved the opposite results in MDA-MB-468 cells. LINC00707, acting as a competing endogenous RNA (ceRNA), could sponge miR-30c to upregulate CTHRC1, thus promoting BC progression.

CONCLUSIONS

LINC00707 was highly expressed in BC tissues and cells. It promoted cell proliferation, invasion, and migration via miR-30c/CTHRC1 regulatory loop. This might provide a novel target for the diagnosis, treatment, and prognosis for BC.

Machine learning-based genome-wide interrogation of somatic copy number aberrations in circulating tumor DNA for early detection of hepatocellular carcinoma

Background

DNAs released from tumor cells into blood (circulating tumor DNAs, ctDNAs) carry tumor-specific genomic aberrations, providing a non-invasive means for cancer detection. In this study, we aimed to leverage somatic copy number aberration (SCNA) in ctDNA to develop assays to detect early-stage HCCs.

Methods

We conducted low-depth whole-genome sequencing (WGS) to profile SCNAs in 384 plasma samples of hepatitis B virus (HBV)-related HCC and cancer-free HBV patients, using one discovery and two validation cohorts. To fully capture the robust signals of WGS data from the complete genome, we developed a machine learning-based statistical model that is focused on detection accuracy in early-stage HCC.

Findings

We built the model using a discovery cohort of 209 patients, achieving an overall area under curve (AUC) of 0.893, with 0.874 for early-stage (Barcelona clinical liver cancer [BCLC] stage 0-A) and 0.933 for advanced-stage (BCLC stage B-D). The performance of the model was then assessed in two validation cohorts (76 and 99 patients) that only consisted of patients with stage 0-A HCC. Our model exhibited a robust predictive performance, with an AUC of 0.920 and 0.812 for the two validation cohorts. Further analyses showed the impact of tumor sample heterogeneity in model training on detecting early-stage tumors, and a refined model addressing the heterogeneity in the discovery cohort significantly increased model performance in validation.

Interpretation

We developed an SCNA-based, machine learning-driven model in the non-invasive detection of early-stage HCC in HBV patients and demonstrated its performance through strict independent validations.

Correlation analysis between ADAMTS-13 gene polymorphism and hypertension-induced atrial fibrillation

OBJECTIVE

The aim of this study was to explore the relationships between ADAMTS-13 gene polymorphisms and hypertension-induced atrial fibrillation (AF).

PATIENTS AND METHODS

A total of 200 hypertensive patients without AF (hypertension group) and 200 hypertensive patients with AF (AF group) treated in our hospital were enrolled. Then, peripheral blood was drawn from these subjects enrolled, and the genomic deoxyribonucleic acids (DNAs) were extracted for analysis of ADAMTS-13 gene polymorphism. Next, Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) was employed to determine the expression of ADAMTS-13 gene, and the correlations of ADAMTS-13 gene polymorphism with ADAMTS-13 gene expression and clinical indicators were analyzed.

RESULTS

Results revealed that there was a difference in the distribution of alleles of ADSMTS-13 rs3094374 (p=0.046) and rs34054981 (p=0.039) between AF group and hypertension group. The frequency of T allele of the locus rs3094374 and that of the locus rs34054981 in ADSMTS-13 gene was higher in AF group than that in hypertension group. The distribution of genotypes of ADSMTS-13 rs28503257 (p=0.047) and rs34054981 (p=0.013) in AF group were different from those in hypertension group, and AF group had lower frequency of GA genotype of ADAMTS-13 rs28503257 and higher frequency of CT genotype of ADAMTS-13 rs34054981 than hypertension group. Besides, a difference was found in the distribution of ADSMTS-13 rs3094374 between AF group and hypertension group in recessive model (p=0.043), and the frequency of TC + CC was higher in the recessive model. Moreover, the distribution of the haplotypes CAT (p=0.012) and CGT (p=0.031) in ADAMTS-13 gene showed a difference between AF group and hypertension group. The linkage disequilibrium of the loci rs3094374 and rs28503257 in ADAMTS-13 gene was relatively great (D'=0.293). In addition, the polymorphism of the locus rs34054981 in ADAMTS-13 gene had an association with ADAMTS-13 gene expression (p<0.05). The expression of ADAMTS-13 gene was lower in patients carrying genotype TT in AF group. Furthermore, the ADAMTS-13 rs3094374 polymorphism was related to international normalized ratio (INR) (p=0.034), and the ADAMTS-13 rs28503257 polymorphism was correlated with the levels of brain natriuretic peptide (BNP) (p=0.047) and D-dimer (p=0.033).

CONCLUSIONS

ADAMTS-13 gene polymorphism is correlated with the susceptibility and procession of hypertension-induced AF.

Long noncoding RNA LINC00662 promotes M2 macrophage polarization and hepatocellular carcinoma progression via activating Wnt/β-catenin signaling

Tumor-associated macrophages have important roles in hepatocellular carcinoma (HCC) initiation and progression. Long noncoding RNAs (lncRNAs) have also been reported to be involved in HCC. In this study, we explored how lncRNA LINC00662 may influence HCC progression through both tumor cell-dependent and macrophage-dependent mechanisms. LINC00662 was found to be upregulated in HCC, and high LINC00662 levels correlated with poor survival of HCC patients. LINC00662 upregulated WNT3A expression and secretion via competitively binding miR-15a, miR-16, and miR-107. Through inducing WNT3A secretion, LINC00662 activated Wnt/β-catenin signaling in HCC cells in an autocrine manner and further promoted HCC cell proliferation, cell cycle, and tumor cell invasion, while repressing HCC cell apoptosis. In addition, acting through WNT3A secretion, LINC00662 activated Wnt/β-catenin signaling in macrophages in a paracrine manner and further promoted M2 macrophage polarization. Via activating Wnt/β-catenin signaling and M2 macrophages polarization, LINC00662 significantly promoted HCC tumor growth and metastasis in vivo. Hence, targeting LINC00662 may provide novel therapeutic strategy against HCC.

Porcine FcγRIIb mediated PRRSV ADE infection through inhibiting IFN-β by cytoplasmic inhibitory signal transduction

Antibody-dependent enhancement (ADE) in porcine reproductive and respiratory syndrome virus (PRRSV) infection is a significant obstacle to the development of effective vaccines for controlling PRRS. Our previous results have demonstrated that porcine FcγRIIb (poFcγRIIb) play an important role in mediating ADE of PRRSV infection in vitro. However, the underlying mechanisms involved in poFcγRIIb mediated-ADE are still not clear. In this study, MARC-145 cel1 lines stably expressing mutated poFcγRIIb (MARC-poFcγRIIb-T and MARC-poFcγRIIb-CT) in cytoplasm were established and the capacity of poFcγRIIb mutants in mediating ADE of PRRSV was investigated. Our results showed that removal of cytoplasmic domain or disruption the tyrosine residue within ITIM (immunoreceptor tyrosine-based inhibition motif) of the poFcγRIIb abolished the ability of poFcγRIIb to mediate ADE of PRRSV. Furthermore, we found that SHIP1 and TBK1 were involved in poFcγRIIb-mediated ADE of PRRSV infection. Taken together, our findings indicated that poFcγRIIb mediated the ADE pathway of PRRSV infection through recruiting SHIP-1, which further inhibited of TBK-1-IRF3-IFN-β signaling pathway to enhance PRRSV infection. These findings will contribute to the molecular mechanism of ADE infection and provide some implications for vaccine development.

Mitochondrial fission-induced mtDNA stress promotes tumor-associated macrophage infiltration and HCC progression

Tumor-associated macrophages (TAMs) contribute to hepatocellular carcinoma (HCC) progression. However, the molecular mechanism underlying the infiltration of TAMs into HCC microenvironment is largely unclear. Recent studies have reported that alteration of mitochondrial nucleoid structures induces mitochondrial DNA (mtDNA) release into the cytosol, which is recognized as mtDNA stress, and consequently regulates innate immunity. Here we aimed to investigate whether mitochondrial fission induces mtDNA stress and then promotes TAM infiltration and HCC progression. Confocal microscopy and real-time PCR were used to detect cytosolic mtDNA content in HCC cells. The relationship between the expression of mitochondrial fission key regulator dynamin-related protein 1 (Drp1) and the percentage of CD163 (a marker of TAMs)-positive cells was investigated in HCC tissues using immunohistochemistry. Finally, the effect of Drp1 overexpression in HCC cells on recruitment and polarization of TAMs was investigated. Our data showed that increased Drp1 expression was positively correlated with the infiltration of TAMs into HCC tissues. Drp1-mediated mitochondrial fission induced the cytosolic mtDNA stress to enhance the CCL2 secretion from HCC cells by TLR9-mediated NF-κB signaling pathway, and thus promoted the TAM recruitment and polarization. Depleting cytosolic mtDNA using DNase I or blocking TLR9 pathway by TLR9 antagonist, siRNA for TLR9 or p65 in HCC cells with Drp1 overexpression significantly decreased the recruitment and polarization of TAMs. Blocking CCR2 by antagonist significantly reduced TAM infiltration and suppressed HCC progression in mouse model. In conclusion, our findings reveal a novel mechanism of TAM infiltration in HCC by mitochondrial fission-induced mtDNA stress.

Tenofovir disoproxil fumarate induces pheochromocytoma cells apoptosis

Despite the triumph of highly active antiretroviral therapy (HAART) in anti-HIV infection, more than half of the HIV infection individuals receiving antiretroviral therapy acquire HIV-associated neurocognitive disorder (HAND). Previously researches had reported that the HAART neurotoxicity is implicated in HAND-related morbidity. The molecular mechanism of HAND is not clear. Tenofovir disoproxil fumarate (TDF) is a novel nucleotide reverse transcriptase inhibitor (NRTI), which was recommended as first-line therapeutic schedule for free AIDS antiviral drugs. Whether the neurotoxicity of TDF is associated with HAND is not well known. In this study, the cell viability of TDF-treated pheochromocytoma cells (PC-12) line was detected using MTT assay, while apoptosis was evaluated by Hoechst 33342 staining, TUNEL assay, as well as flow cytometry. In addition, the level of reactive oxygen species and BAX protein expression were evaluated using DCFH-DA staining and western blotting. The results showed that the proliferation of PC-12 cells was significantly inhibited by TDF. The morphological assay, TUNEL assay and flow cytometry showed that TDF efficiently triggered apoptosis in PC-12 cells. The reactive oxygen species levels were BAX expression was markedly up-regulated in PC-12 cells after treatment with TDF. These findings indicated that TDF may induce PC-12 cell apoptosis. TDF has neural toxicity effect that is relevant to the cell apoptosis, which may be related to the increasing prevalence of HAND.

The attenuation of HIV-1 Tat-induced neurotoxicity by Salvianic acid A and Danshen granule

The neurotoxicity of HIV-1 Tat protein contributes significantly to the pathogenesis of HAND, and hence the attractive therapeutic strategies focusing on Tat-induced neurotoxicity are warranted. Salvia miltiorrhiza have been known to antioxidant property and neuroprotective effects. The Danshen granule is the pharmaceutical dosage forms of Salvia miltiorrhiza and Salvianic acid A is an essential chemical constituent of Salvia miltiorrhiza. However, the protective effects of Salvianic acid A and Danshen granule on Tat-induced neurotoxicity remain unknown. Here, we found that Salvianic acid A and Danshen granule remarkable inhibited Tat-induced cell death, blocked LDH release and rescued dendritic spine loss. Furthermore, Salvianic acid A and Danshen granule significantly ameliorates Tat-induced intracellular ROS and MDA production, attenuates cell apoptosis. In addition, Salvianic acid A and Danshen granule pretreatment obviously increases antioxidant enzymatic activity of CAT, SOD and GSH-Px and inhibits apoptotic pathways. In conclusion, this study demonstrated that Salvianic acid A and Danshen granule provides substantial neuroprotection against Tat-induced neurotoxicity, which may be new therapeutic agent in Tat induced HAND or neurodegenerative diseases.

Development of an immunochromatographic strip for detection of antibodies against porcine reproductive and respiratory syndrome virus

A simple and rapid immunochromatographic test strip incorporating a colloidal gold-labeled recombinant Nsp7 antigen probe was successfully developed for the detection of anti-porcine reproductive and respiratory syndrome virus (PRRSV) antibodies in swine. Recombinant Nsp7 protein of PRRSV labeled with colloidal gold was dispensed on a conjugate pad for use as the detector. Staphylococcal protein A and purified porcine anti-Nsp7 antibodies were blotted on a nitrocellulose membrane to form test and control lines, respectively. A comparison of the strip with standard diagnostic tests, enzyme-linked immunosorbent assays and immunoperoxidase monolayer assay, was also performed. The immunochromatographic test strip was shown to be of high specificity and sensitivity. Furthermore, the strip assay is rapid and easy to perform with no requirement for professional-level skills or equipment. It is suggested that the immunochromatographic test strip can be used to quickly and accurately detect PRRSV antibody and to be suitable for diagnostic purposes in the field.

H9N2 influenza virus isolated from minks has enhanced virulence in mice

H9N2 is one of the major subtypes of influenza virus circulating in poultry in China, which has a wide host range from bird to mammals. Two H9N2 viruses were isolated from one mink farm in 2014. Phylogenetic analysis showed that internal genes of the H9N2 viruses have close relationship with those of H7N9 viruses. Interestingly, two H9N2 were separated in phylogenetic trees, indicating that they are introduced to this mink farm in two independent events. And further mice studies showed that one H9N2 caused obvious weight loss and 20% mortality in infected mice, while another virus did not cause any clinical sign in mice infected at the same dose. Genetic analysis indicated that the virulent H9N2 contain a natural mutation at 701N in PB2 protein, which was reported to contribute to mammalian adaptation. However, such substitution is absent in the H9N2 avirulent to mice. Circulation of H9N2 in mink may drive the virus to adapt mammals; continual surveillance of influenza virus in mink was warranted.

Alterations of telomere length and mtDNA copy number are associated with overall survival in hepatocellular carcinoma patients treated with transarterial chemoembolization

PURPOSE

Increasing evidence suggests that alterations in mitochondrial DNA (mtDNA) copy number (mtDNAcn) and relative telomere length (RTL) may be implicated in the tumorigenesis of several malignancies. Alterations of both RTL and mtDNAcn are generally accepted as independent biomarkers for predicting risk and prognosis in various cancers. The aim of this study was to evaluate the prognostic value of combining leukocyte RTL with mtDNAcn (RTL-mtDNAcn) in hepatocellular carcinoma (HCC).

METHODS

RTL and mtDNAcn in peripheral blood leukocytes (PBLs) were measured using a real-time PCR-based method in a total of 250 HCC patients treated with transcatheter arterial chemoembolization (TACE). We evaluated the associations between RTL and/or mtDNAcn and HCC overall survival using Kaplan-Meier curve analysis and Cox proportional hazards regression model.

RESULTS

We found that patients with longer leukocyte RTL or lower mtDNAcn had shorter overall survival time. The univariate analysis (HR 1.63, 95 % CI 1.23-2.17, P = 7.7 × 10(-4)) and multivariate analysis (HR 1.78, 95 % CI 1.31-2.42, P = 2.4 × 10(-4)) indicated that longer leukocyte RTL was significantly associated with poorer OS in HCC patients. Kaplan-Meier curve analysis showed that patients with longer RTL had shorter overall survival time than those with shorter RTL (log-rank P = 0.001). Patients with lower mtDNA copy number was significantly associated with poorer OS by Cox proportional hazards model using both univariate (HR 1.60, 95 % CI 1.21-2.13, P = 0.001) and multivariate analyses (HR 1.77, 95 % CI 1.30-2.41, P = 2.8 × 10(-4)). Kaplan-Meier curve analysis showed that patients with lower mtDNA content had significantly shorter overall survival time than those with higher mtDNA content (log-rank P = 0.001). Furthermore, combination of leukocyte RTL and mtDNAcn significantly improved the efficacy of predicting HCC prognosis. Patients with longer RTL and lower mtDNAcn exhibited a significantly poorer overall survival in both the univariate analysis (HR 2.21, 95 % CI 1.52-3.22, P = 3.5 × 10(-5)) and multivariate analysis (HR 2.60, 95 % CI 1.73-3.90, P = 4.3 × 10(-6)). The effect on patient prognosis was more evident in patients with longer RTL and lower mtDNAcn than in those with shorter RTL and lower mtDNA (HR 2.11, 95 % CI 1.34-3.32, P = 0.001) or in those with longer RTL and higher mtDNA (HR 2.10, 95 % CI 1.34-3.27, P = 0.001).

CONCLUSIONS

Our data suggest that combination of leukocyte RTL-mtDNAcn may be a potential efficient prognostic marker for HCC patients receiving the TACE treatment.

Antibody-dependent enhancement of PRRSV infection down-modulates TNF-α and IFN-β transcription in macrophages

Porcine reproductive and respiratory syndrome (PRRS) is an infectious disease, resulting in important economic losses in pig farming. Previous studies have shown that Fcγ receptor (FcγR)-mediated entry of infectious PRRSV immune complexes into macrophages plays a pivotal role in the pathogenesis of the disease. This study demonstrates that PRRSV was able to suppress the transcription of key antiviral genes tumor necrosis factor-α (TNF-α) and interferon-β (IFN-β), when infection was via the ADE pathway. Investigation of this infection pathway found that PRRSV suppresses the antiviral genes by disrupting the transcription of the genes coding for the associated transcription factors interferon regulatory factor-1 (IRF-1), interferon regulatory factor-3 (IRF-3) and nuclear factor kappa B (NF-κB). The ADE pathway of infection allows PRRSV to specifically target antiviral genes and alters the innate intracellular immune responses in macrophages. The ADE mechanism described in this study furthers our understanding of pathogenesis following PRRSV infection and is of general relevance to virally induced disease and in relation to antiviral vaccination strategies.

Impairment of the antibody-dependent phagocytic function of PMNs through regulation of the FcγRs expression after porcine reproductive and respiratory syndrome virus infection

Porcine reproductive and respiratory syndrome (PRRS) is identified as one of the most important etiological agents in multifactorial respiratory disease of swine and can predispose pigs to secondary infections by other pathogens, usually bacteria. To understand the mechanism for an increased susceptibility to secondary bacterial infections, we investigated the antibody-dependent phagocytosis behaviour and killing ability of PMNs after infection by PRRSV strains BJ-4 or HN07-1. PMN’s antibody-dependent phagocytosis and their ability to kill E.coli were both noticeably decreased following PRRSV infection, in particular with the highly pathogenic strain HN07-1. As the change in this function of the PMNs may reflect a variation in the expression of FcγRs, the expression profiles of the activating and the inhibitory FcγRs were examined. We found that RNA expression of the inhibitory receptor FcγRIIB was up-regulated post-infection, and this was greater after infection with the more virulent PRRSV strain HN07-1. The activating receptor FcγRIIIA RNA expression was on the other hand inhibited to the same extent by both PRRSV strains. Neutralizing antibody titers post-infection by PRRSV strains BJ-4 or HN07-1 were also detected. All of the pigs in infection groups showed viraemia by the end of the study (56 DPI). These observations may help to understand the mechanism of increased susceptibility to secondary bacterial infections following PRRSV infection.

Porcine FcγRIIb mediates enhancement of porcine reproductive and respiratory syndrome virus (PRRSV) infection

Antibody-dependent enhancement (ADE) of virus infection caused by the uptake of virus-antibody complexes by FcγRs is a significant obstacle to the development of effective vaccines to control certain human and animal viral diseases. The activation FcγRs, including FcγRI and FcγRIIa have been shown to mediate ADE infection of virus. In the present paper, we showed that pocine FcγRIIb, an inhibitory FcγR, mediates ADE of PRRSV infection. Stable Marc-145 cell lines expressing poFcγRIIb (Marc-poFcγRII) were established. The relative yield of progeny virus was significantly increased in the presence of sub-neutralization anti-PRRSV antibody. The Fab fragment and normal porcine sera had no effect. Anti-poFcγRII antibody inhibited the enhancement of infection when cells were infected in the presence of anti-PRRSV antibody, but not when cells were infected in the absence of antibody. These results indicate that enhancement of infection in these cells by anti-PRRSV virus antibody is FcγRII-mediated. Identification of the inhibitory FcγR mediating ADE infection should expand our understanding of the mechanisms of pathogenesis for a broad range of infectious diseases and may open many approaches for improvements to the treatment and prevention of such diseases.

Porcine reproductive and respiratory syndrome virus and bacterial endotoxin act in synergy to amplify the inflammatory response of infected macrophages

In 2006 China experienced outbreaks of a severe form of porcine reproductive and respiratory syndrome (PRRS) characterized by high fever, morbidity and mortality in swine irrespective of age. It is thought that secondary bacterial infections may contribute to the generation of this severe form of the disease. To determine the mechanisms by which a highly pathogenic PRRSV strain causes high fever we used an in vitro model to investigate the production of the pro-inflammatory cytokines IL-1β and TNF-α by macrophages in response to inoculation with PRRSV with or without LPS. Firstly we demonstrated, through an animal inoculation trial, that the isolate HN07-1 was a highly pathogenic strain and sequencing showed that the virus had the same genomic characteristics as previously described isolates. Porcine alveolar macrophage (PAM) cultures infected with PRRSV strains showed increased cytokine secretion and this was greater in the more virulent strain. Addition of LPS further increased cytokine secretion and again the effect was greater with the more virulent strain. Incubation of PAMs with PRRSV strain HN07-1 resulted in a significant increase in surface CD14 expression. This may explain the synergistic action between PRRSV and LPS in the induction of inflammatory cytokine secretion seen in the PAMs and so offer an explanation for the high fever that is characteristic of infections by the highly pathogenic PRRSV.

Development of an immunochromatographic strip for the detection of antibodies against foot-and-mouth disease virus serotype O

An immunochromatographic strip was developed for the serological detection of type O foot-and-mouth disease (FMD) in swine. In the strip, the expressed protein of VP1, the main protective antigen of FMDV, labeled with colloidal gold was used as the detector, the staphylococcal protein A (SPA) and swine anti-foot-and-mouth disease virus (FMDV) antibody were blotted on the nitrocellulose membrane for the test and control lines, respectively. 296 swine serum samples were collected to evaluate the characteristics of the strip in comparison with existing commercial liquid-phage blocking ELISA (LPB ELISA) kit and peptide ELISA kit. The strip was shown to be of high specificity and sensitivity. Furthermore, the dipstick assay based on the strip is rapid (5 min) and easy to perform with no requirement of professional skills, reagents nor equipment. This suggests that the immunochromatographic strip is an acceptable alternative for use in clinical laboratories lacking specialized equipment and for field diagnosis.

Relationship between TFAM Gene Polymorphisms and Endurance Capacity in Response to Training

The aim of this study was to explore whether polymorphisms in mitochondrial transcription factor A ( TFAM) gene are associated with endurance capacity in a pretraining state (baseline) and/or in response to a supervised 18-wk endurance training (changes) in 102 young Chinese males (nonathletes). Phenotypes measured were running economy (RE) and V(.)O (2max). Genomic DNA was extracted from white blood cells and the genotypes were analyzed by PCR-RFLP in single nucleotide polymorphisms (SNP) rs1937, rs2306604 and rs1049432. Genotype distributions were in Hardy-Weinberg equilibrium at three loci (p > 0.05). When the three polymorphisms were considered together, three haplotypes were estimated, i.e., G (rs1937)-A (rs2306604)-G (rs1049432) (49 %), G (rs1937)-G (rs2306604)-G (rs1049432) (33 %) and C (rs1937)-G (rs2306604)-T (rs1049432) (18 %). SNPrs1937 and rs1049432 achieved near complete linkage disequilibrium (LD) (D' = 1 and r (2) = 0.903). We found no significant differences in baseline levels of V(.)O (2max) and RE between TFAM genotypes or haplotypes. Similarly, we found no differences for the training-induced changes of both variables. It was concluded that the three polymorphisms in TFAM gene rs1937, rs2306604 and rs1049432 do not predict endurance capacity/trainability, at least in Chinese males.

Is there an association between PPARGC1A genotypes and endurance capacity in Chinese men?

Our purpose was to determine the possible association between genotypes of three polymorphisms (Gly482Ser, Thr394Thr and A2962G) of the peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A) gene, on one hand, and both the pre- (baseline) and post-training levels of maximal (i.e., maximal oxygen uptake [VO2max]) and submaximal human endurance capacity (i.e., running economy [RE]). We studied 102 young males (physically active, non-athletes; age: 19+/-1 yrs) from Northern China (of Han origin) who underwent a 18-week endurance training (running) program and were tested on a treadmill (for VO2max and RE determination) before and after training. None of the VO2max and RE related traits were associated with the Gly482Ser and Thr394Thr polymorphisms at baseline or after training. The A2962G polymorphism was however associated with VO2max at baseline, as carriers of the G allele (AG+GG genotypes; n=49) had higher levels of VO2max than the AA group (n=53) (58.2+/-4.3 vs 56.3+/-3.9 mL/kg/min; P=0.017). Our results do not support previous data on Caucasians showing an association between the Gly482Ser variant and VO2max but suggest the potential role of another polymorphism (A2962G) to explain individual VO2max differences in Chinese men.

Early changes of arginine vasopressin and angiotensin II in patients with acute cerebral injury

OBJECTIVE

To study the changes and clinical significance of arginine vasopressin (AVP) and angiotensin II (AT-II) in patients with acute moderate and severe cerebral injury.

METHODS

The early plasma concentration was checked by radioimmunoassay in 47 cases of acute moderate and severe cerebral injury, 30 cases of non-cerebral injury and 30 healthy volunteers.

RESULTS

The early plasma concentrations of AVP (50.23 ng/L +/- 15.31 ng/L) and AT-II (248.18 ng/L +/- 82.47 ng/L) in cerebral injury group were higher than those in non-cerebral injury group (AVP for 30.91 ng/L +/- 11.48 ng/L and AT-II for 120.67 ng/L +/- 42.49 ng/L, P<0.01). The early plasma concentrations of AVP and AT-II in cerebral injury group were also obviously higher than those of the volunteers (AVP for 5.16 ng/L +/- 4.23 ng/L and AT-II for 43.11 ng/L +/- 16.39 ng /L, P<0.001). At the same time, the early plasma level of AVP (58.90 ng/L +/- 18.12 ng/L) and AT-II (292.13 ng/L +/- 101.17 ng/ L) was higher in severe cerebral injured patients than moderate cerebral injured ones (AVP for 36.68 ng/L +/- 12.16 ng/L and AT-II for 201.42 ng/L +/- 66.10 ng/L, P<0.01). The early level of AVP and AT-II was negatively related to the GCS scales in acute cerebral injury. The early plasma concentrations of AVP (45.98 ng/L +/- 13.48 ng/L) and AT-II (263. 28 ng/L +/- 80.23 ng/L) were lower in epidural hematoma group than those of subdural hematoma and cerebral injury group (AVP for 64.12 ng/L +/- 15.56 ng /L and AT-II for 319.82 ng/L +/- 108.11 ng/L, P<0. 01).

CONCLUSIONS

AVP and AT-II may play an important role in pathophysiologic process in the secondary cerebral injury. The more severe the cerebral injury is, the higher the early level of AVP and AT-II will be. The early plasma level of AVP and AT-II may be one of the severity indexes of cerebral injury.

Ornithine decarboxylase, kidney size, and the tubular hypothesis of glomerular hyperfiltration in experimental diabetes

In early diabetes, the kidney grows and the glomerular filtration rate (GFR) increases. This growth is linked to ornithine decarboxylase (ODC). The study of hyperfiltration has focused on microvascular abnormalities, but hyperfiltration may actually result from a prior increase in capacity for proximal reabsorption which reduces the signal for tubuloglomerular feedback (TGF). Experiments were performed in Wistar rats after 1 week of streptozotocin diabetes. Kidney weight, ODC activity, and GFR were correlated in diabetic and control rats given difluoromethylornithine (DFMO; Marion Merrell Dow, Cincinnati, Ohio, USA) to inhibit ODC. We assessed proximal reabsorption by micropuncture, using TGF as a tool for manipulating single-nephron GFR (SNGFR), then plotting proximal reabsorption versus SNGFR. ODC activity was elevated 15-fold in diabetic kidneys and normalized by DFMO, which also attenuated hyperfiltration and hypertrophy. Micropuncture data revealed an overall increase in proximal reabsorption in diabetic rats too great to be accounted for by glomerulotubular balance. DFMO prevented the overall increase in proximal reabsorption. These data confirm that ODC is required for the full effect of diabetes on kidney size and proximal reabsorption in early streptozotocin diabetes and are consistent with the hypothesis that diabetic hyperfiltration results from normal physiologic actions of TGF operating in a larger kidney, independent of any primary malfunction of the glomerular microvasculature.

Adenosine formed by 5'-nucleotidase mediates tubuloglomerular feedback

Nephron function is stabilized by tubuloglomerular feedback (TGF). TGF operates within the juxtaglomerular apparatus, sensing changes in tubular flow and eliciting compensatory changes in single nephron GFR (SNGFR). The mediator(s) of TGF remains unconfirmed. One theory is that ATP consumed in active transport by the macula densa leads to formation of adenosine, which causes glomerular vasoconstriction. We performed micropuncture in rats to test this hypothesis. Adenosine activity was manipulated by microperfusing nephrons with adenosine A1 receptor blocker, A1-agonist, or 5'-nucleotidase inhibitor. Effects on TGF were characterized by changes in TGF efficiency (the compensation for small perturbations in tubular flow) and by changes in the maximum range over which TGF can cause SNGFR to change. These data were further applied to generate TGF profiles [SNGFR versus late proximal flow (V(LP))]. TGF efficiency was significantly reduced by blocking A1-receptors. TGF efficiency, TGF range, and the slope of the TGF profile (DeltaSNGFR/DeltaV(LP)) were all significantly reduced by blocking 5'-nucleotidase. When adenosine activity was clamped by combining 5'-nucleotidase inhibitor with A1-agonist to determine whether TGF requires adenosine to be present or to fluctuate, the TGF slope was reduced by 83%, indicating that adenosine activity must fluctuate for normal TGF to occur and that adenosine is a mediator of TGF.

Temporal adjustment of the juxtaglomerular apparatus during sustained inhibition of proximal reabsorption

Tubuloglomerular feedback (TGF) stabilizes nephron function by causing changes in single-nephron GFR (SNGFR) to compensate for changes in late proximal flow (VLP). TGF responds within seconds and reacts over a narrow range of VLP that surrounds normal VLP. To accommodate sustained increases in VLP, TGF must reset around the new flow. We studied TGF resetting by inhibiting proximal reabsorption with benzolamide (BNZ; administered repeatedly over a 24-hour period) in Wistar-Froemter rats. BNZ acutely activates TGF, thereby reducing SNGFR. Micropuncture was performed 6-10 hours after the fourth BNZ dose, when diuresis had subsided. BNZ caused glomerular hyperfiltration, which was prevented with inhibitors of macula densa nitric oxide synthase (NOS). Because of hyperfiltration, BNZ increased VLP and distal flow, but did not affect the basal TGF stimulus (early distal salt concentration). BNZ slightly blunted normalized maximum TGF response and the basal state of TGF activation. BNZ sensitized SNGFR to reduction by S-methyl-thiocitrulline (SMTC) and caused the maximum TGF response to be strengthened by SMTC. Sensitization to type I NOS (NOS-I) blockers correlated with increased macula densa NOS-I immunoreactivity. Tubular transport measurements confirmed that BNZ affected TGF within the juxtaglomerular apparatus. During reduced proximal reabsorption, TGF resets to accommodate increased flow and SNGFR through a mechanism involving macula densa NOS.

[Effect of enoxacin on pharmacokinetics of theophylline in rats]

In order to obtain an experimental evidence for Enoxacin(ENX) to be correctly used in clinical treatment, we studied the effect of ENX on the pharmacokinetic parameters of theophylline(TP). A single oral dose of TP 20 mg/kg was given to rats and ENX(300 mg/kg, 450 mg/kg) was co-administered orally three times to those rats. The plasma concentrations of TP were determined by HPLC after TP was administered 1, 2, 3, 5, 7, 12 and 24 hrs. The results showed that TP was eliminated by one compartment model. TP plasma concentrations and AUC were significantly increased. T1/2 beta of TP was prolonged. The total clearance of TP was decreased when compared with the control. This interaction was dose-dependent. It was concluded that the interaction between ENX and TP existed. Concomitant use of ENX with TP should be avoided.

[Effect of po li gan capsule on immunofunction in mice]

This study aimed at the immune response of mice to Po Li Gan Capsule (PLGC). The effects of PLGC on phagocytosis of phagocyte, on serum hemolysin, and on IL-1, IL-2 in mice were investigated. The results showed that the coefficient and index of phagocytosis obviously increased in the experiment group, compared with that in the control group (P < 0.01); the serum hemolysin in the experiment group increased too (P < 0.01). The results also showed that PLGC could restore the capacity of macrophage for secreting IL-1 that had been inhibited by cyclophosphamide and PLGC could enhance the release of IL-2 from spleen cell in the experiment group (P < 0.05-0.01). These suggest that PLGC enhances both cellular and humoral immunity function in mice.

[Study on the beta-lactamases of the Escherichia coli HX88108 resistant to ceforperazon]

E. coli HX88108 was isolated from a patient and found to produce plasmid-encode beta-lactamases with conferring highly resistance to ceforperazone(CPZ). The beta-lactamases of the E. coli HX88108 and transformants pFC, pFT1, pFT2 and pFT3 were studied. The beta-lactamases stability test among 11 beta-lactam antibiotics showed that beta-lactamases from E. coli HX88108. pFC, pFT1, readily hydrolyzed penicillins, the first, second-generation cephalosporins and CPZ. beta-lactamases of pFT2 and pFT3 hydrolyzed penicillins more strongly than cephalosporins. On the other hand, experiments of inhibiting enzyme were carried out. The results indicated that beta-lactamases of HX88108, pTF1, pFT2 and pFT3 were inhibited by clavulanic acid(CA) and sulbactam (SBT). Enzyme of pFC was inhibited poorly by CA and SBT. Through isoelectric focusing technique, the PIs were as follows: HX88108 contained three beta-lactamases, of which the PIs were 5.25, 5.3 and 5.6 respectively; the PIs of beta-lactamases from pFT2, pFT3, were 5.3 and 5.6. pFC and pFT1 were different plasmids encoded beta-lactamases with the same PI 5.25. The results indicate that the beta-lactamases of E. coli HX88108 may be a new member in TEM farmily.

[The mechanism of a new anthracycline antitumor agent: 1,4-bis [2-(2,2-dimethyl-oxazolidin-3-yl)ethylamino]-1,4-didehydroxy-eta pyrromycinone(AD-89)]

Agarose gel electrophoresis and spectroscopy were used to investigate the interaction of AD-89 with DNA. The effect of drug on intact cell DNA was evaluated by using alkaline elution technique. The results showed that AD-89 decreased the mobility of supercoiled PUC9 DNA significantly. The interaction of calf thymus DNA with AD-89 led to the red shift of the peaks of absorption, and the greater the ratio of DNA/AD-89 was the greater the red shift would be. These results are similar to those of mitoxantrone (DHAQ) and thus suggest that AD-89 is an intercalator. The results of alkaline elution showed that AD-89 produced single-strand breaks at high dose. In contrast to DHAQ, AD-89 did not produce protein-associated breaks. AD-89 produced significantly DNA interstrand cross-linking at 5 and 10 mumol/ L. It also produced DNA protein crosslinks. These results demonstrate that AD-89 is an intercalator and can produce DNA interstrand cross-linking.

Percutaneous transluminal balloon pulmonary valvuloplasty using domestic balloon catheter for congenital pulmonary valve stenosis in children

OBJECTIVE

To estimate the effect of percutaneous balloon pulmonary valvuloplasty (PBPV) using domestic balloon catheter for congenital pulmonary valve stenosis (PVS) in infants and children.

PATIENTS AND METHODS

The data of 70 patients aged from 1.5 to 12 years (mean 5.5 +/- 3.4 years) who underwent PBPV using domestic balloon catheter for PVS in our institution were reviewed. Sixty-six patients had dome-shaped valve stenosis, and 4 had displastic valve stenosis. SaO2 reduced in 5 patients and associated open foramen ovale was noted in 23. Predilatation, right ventricular systolic pressure ranged from 60 to 234 mmHg (mean 115.75 +/- 36.15 mmHg). The systolic gradient (delta P) from right ventricle to pulmonary artery was 89.92 +/- 38.25 mmHg. Balloon diameter was selected 120%-142% of pulmonary valve annulus diameter (mean 132%). All patients were followed up for 3 months-4 years by means of clinical examination. ECG, 2D-UCG, and Doppler-UCG.

RESULTS

After dilatation, delta P reduced from 89.92 +/- 38.25 to 14.65 +/- 11.40 mmHg (P < 0.001). The rate of decrease in transvalve gradient (delta P) was 83.7%. No patients experienced procedure-related events. Mid-term follow-up showed that no patients had clinical and instrumental complications. Doppler and ECG analyses showed that delta P did not change significantly similar to immediate gradient after PBPV and right ventricular hypertrophy disappeared progressively 6 months after PBPV.

CONCLUSIONS

PBPV is a useful, safe and definitive procedure in the treatment of isolated PVS in infants and children. The properties and features of the balloon catheter produced by Shanghai Med-Tech Factory are similar to those of Med-Tech balloon catheter of U.S.A.

[Preliminary mechanism studies of siwenmycin on the inhibition of nucleic acid syntheses]

Siwenmycin, isolated from a streptomyces culture, is a new member of aclacinomycin analogues. It exhibited a remarkable inhibitory effect on the biosynthesis of DNA and RNA in vivo. In order to recognize the mechanism of the inhibitions, the reactions of siwenmycin to DNA template, DNA polymerase I and RNA polymerase were studied. Experimental results showed that siwenmycin could intercalate DNA, but it did not inhibit DNA polymerase I-mediated DNA repair replication and T7RNA polymerase-mediated DNA transcription. This indicates that siwenmycin is not a damage to the DNA template function, nor will it inhibit DNA polymerase I and T7RNA polymerase, though it can intercalate DNA.

Invertidos sexuales, tortilleras, and maricas machos: the construction of homosexuality in Buenos Aires, Argentina, 1900-1950

The author discusses Argentinean construction of homosexuality from 1900 to 1950 in the context of the raging debate of the essentialists versus social constructionists. The history of sexual inverts is discussed with reference to early sexologists. After a broad exploration of sexual inversion, the author turns to the Argentinean doctors who distinguish between acquired and congenital inverts. There was much resistance to the medical and legal establishments as there were autobiographies written by inverts, who subverted the medical views of the day. Finally, Bao concludes that there was, indeed, an Argentine construction of homosexuality, and that there were similarities between Buenos Aires and other large European cities. It is also noted that at the beginning of the twentieth century, there was a developed Argentine subculture of inverts who had meeting places, fashion, sexual tastes, and customs.

[A study on pharmacokinetics of 3H-mitoxantrone in experimental animals]

Mitoxantrone (DHAQ) we studied is a new semisynthetic antitumor drug prepared in China. This paper reports the pharmacokinetic studies of 3H-mitoxantrone in mice by liquid scintillation. The results showed that the decline of radioactivity in the plasma was a biphasic curve after intramuscular and intravenous injection in rats. The adsorption of 3H-DHAQ was ready and complete after intramuscular injection, it was widely distributed in body tissues. The concentration order of various organs was liver greater than intestine greater than kidney greater than lung greater than heart greater than muscles greater than brain. The elimination of the drug was slow, T1/2 was 42.56 h. In 72 h after administration the cumulative excretion of radioactivity in urine was 7% of the total dose, while that in feces was 43%. The main forms of the drug in urine were its metabolites.