[Clinicopathological features and differential diagnosis of metanephric adenoma: a report of sixteen cases]

OBJECTIVE

To study the clinicopathological features and differential diagnosis of metanephric adenoma (MA).

METHODS

The clinicopathological data of 16 cases with MA diagnosed and treated in Peking University First Hospital from 2004 to 2016 were retrospectively analyzed, and the clinical characteristics, pathologic parameters, differential diagnosis, treatment options and prognosis of MA were analyzed with literature review.

RESULTS

The patients included 10 females and 6 males. The age of patients ranged from 14 to 83 years (mean=33.7 years). The partial nephrectomy was carried out for most patients. All cases were located in renal codex with 3 growing into the renal sinus. Histologically, the tumor was composed of tubules, papillary or glomeruloid structures and psammoma bodies were focally seen. Immunohistochemical study showed that all the cases expressed vimentin, and 94% cases expressed CD57, 63% WT1, 75% AE1/AE3, 19% cytokeratin 7 (CK7) and 13%α-methylacyl-CoA racemase (AMACR), and negative expressions for MA included CD10, neuron-specific enolase (NSE) and CD56. Follow-up information from 1 to 125 months was available in all the patients; and none of the patients showed any evidence of recurrence and metastasis.

CONCLUSION

The benign tumor characteristics of MA are not obvious for preoperative imaging diagnosis, and the diagnosis of MA should be based on the unique pathological features. Positive immunostain of CD57 is a useful indicator for MA diagnosis and differential diagnosis. The partial nephrectomy surgical treatment can achieve good clinical cure with good prognosis.

[Radical cystectomy in patients with pathological non-muscle invasive bladder cancer]

OBJECTIVE

Carcinoma of bladder is the most common malignancy in the urinary system in China. Most patients with this disease had non-muscle invasive bladder cancer (NMIBC) at the time of diagnosis. Radical cystectomy was indicated for patients with high risk or refractory NMIBC. We aimed to investigate the overall survival and disease-specific survival and related influence factors in patients undergoing radical cystectomy for pathological non-muscle invasive bladder cancer.

METHODS

From Jan. 2006 to Dec. 2012, a total of 164 patients with pathological non-muscle invasive bladder cancer underwent radical cystectomy in Peking University First Hospital. Clinical data were retrospectively collected.Incidence of lymph node metastasis and disease recurrence were calculated. The risk factors of disease recurrence were analyzed. Kaplan-Meier plots were used to estimate the overall survival and cancer-specific survival. Multivariate Cox regression analysis was used to evaluate the prognostic factors for survival.

RESULTS

Of all the patients included, 159 had T1 disease, and 5 had CIS only. The median follow-up duration was 46.5 months (range: 7-99 months). Fourteen patients were lost during the follow-up. Lymph node metastasis was noted in 6 patients (3.7%), 4 patients had N1 disease, one patient had N2 disease, and one patient had N3 disease. Disease recurrence occurred in 16 patients (9.8%).The most common recurrence sites were the liver, bones, and lungs. The 5-year overall survival and disease-specific survival for all the patients were 85% and 91%, respectively. The patients who underwent pelvic lymph node dissection showed a better prognosis in terms of disease-specific survival than those without (P=0.012). Patients with recurrence harbored a significant poorer survival (P<0.001). According to univariate Cox regression analysis, whether lymph node dissection was performed was an independent risk factor of disease recurrence (P=0.050, OR=2.695, 95%CI 0.999-7.271). In COX regression model, age (P=0.008, OR=1.071, 95%CI 1.018-1.126) and whether lymph node dissection was performed (P=0.011, OR=3.385, 95%CI 1.329-8.621) were related to disease-specific survival.

CONCLUSION

Patients with pathological non-muscle invasive bladder cancer underwent early radical cystectomy have a favorable prognosis, and bilateral pelvic lymph node dissection is essential for this procedure as it gains a survival benefit for the patients.

[Basal cell carcinoma of prostate: a report of three cases]

To explore the clinical pathological characteristics and improve the recognition in the diagnosis and treatment of basal cell carcinoma (BCC) of prostate. Three cases of BCC of prostate were reported and the relevant literature was reviewed to investigate the diagnosis and treatment of this disease. We analyzed three cases of prostatic BCC. Their ages were within a range of 57 to 83 years. One of them complained of hematuria and two complained of dysuria. All of them presented with prostatic hyperplasia. Two of them presented with high prostate specific antigen (PSA) and one with normal PSA. Case 1 had prostate cancer invasion of bladder, rectal fascia, with lymph node metastasis, bone metastasis and lung metastases. The patient received bladder resection+bilateral ureteral cutaneous ureterostomy+lymph node dissection on November 2, 2014 . Postoperative pathological diagnosis showed BCC. Reexamination of pelvic enhanced MRI in January 8, 2015 suggested pelvic recurrence. Abdominal enhanced CT showed multiple liver metastases and pancreatic metastasis on July 11, 2015. Prostate cancer specific death occurred in October 2015. Case 2 was diagnosed as BCC in prostate biopsy on March 27, 2015. Positron emission tomography and computed tomography (PET-CT) showed pulmonary metastasis and bone metastasis. Then the patient received chemotherapy, endocrine therapy and local radiation therapy. Reexamination of PET-CT on January 11, 2016 showed that the lung metastase tumors and bone metastase tumors were larger than before. Up to January 10, 2016, the patient was still alive. Postoperative pathological changes of transurethral resection of prostate (TURP) in case 3 showed BCC might be considered. The PET-CT suggested residual prostate cancer, which might be associated with bilateral pelvic lymph node metastasis. In April 20, 2016, the review of PET-CT showed pelvic huge irregular hybrid density shadow, about 14.5 cm×10.0 cm×12.9 cm in size, and tumor recurrence was considered. Then the patient received local radiation therapy. The patient survived in the followed upon January 10, 2016. BCC of prostate is a rare subtype. Due to the local infiltrative and distant metastatic potentiality, active management is preferred and a life-long follow-up is necessary.

Targeted gene therapy and in vivo bioluminescent imaging for monitoring postsurgical recurrence and metastasis in mouse models of liver cancer

We investigated the effects of combined targeted gene therapy on recurrence and metastasis after liver cancer resection in nude mice. Twenty BALB/C mice were randomly divided into control and treatment groups with 10 mice in each group and a male/female ratio of 1:1. Luciferase gene-labeled human primary hepatic carcinoma cell line MHCC97-H was then used to prepare a carcinoma model. An optical in vivo imaging technique (OIIT) was used 10 days later to detect the distribution of tumor cells, followed by partial liver resection and gene therapy. In the treatment group, 100 mL phosphate-buffered saline (PBS) containing 1 x 1012 rAAV/AFP/IL-24 gene viral vectors was injected into liver sections and peritumoral posterior peritoneal tissues; in the control group, the same amount of PBS containing 1 x 1012 empty viral vectors was injected at the same sites. OIIT was then used to detect the in vivo tumor metastasis 21 days later. Luciferase gene-labeled human primary hepatic carcinoma cell line MHCC97-H successfully infected 20 nude mice, and OIIT showed that the two groups exhibited metastasis after local tumor resection, but there were more tumor cells in the control group (P < 0.05). rAAV/AFP/IL-24 gene therapy can inhibit recurrence after liver cancer resection.

Interleukin-10 gene promoter region polymorphisms are not associated with BCG osteitis in vaccinated infants

SETTING

Complications arising from bacille Calmette-Guérin (BCG) vaccination were recorded in a national register in Finland until 1988. In the period 1960-1988, 222 patients suffered from BCG osteitis.

OBJECTIVE

To evaluate whether single nucleotide polymorphisms (SNPs) in the promoter region of the gene encoding interleukin 10 (IL-10) are associated with BCG osteitis after vaccination in neonates.

DESIGN

Blood samples of 132 former BCG osteitis patients now aged 21-49 years were analysed in a controlled study for IL10 rs1800896 (-1082G/A), rs1800871 (-819C/T), rs1800872 (-592C/A) and rs1800890 (-3575T/A) polymorphisms.

RESULTS

The frequencies of genotypes of IL10 rs1800896, rs1800871, rs1800872 and rs1800890, the frequencies of variant genotypes and the frequencies of major or minor alleles did not differ between patients and controls. Furthermore, the frequencies of the eight possible combinations of the three IL10 alleles located close to each other (IL10 rs1800896, IL10 rs1800871 and IL10 rs1800872) were surprisingly similar.

CONCLUSION

Our results suggest that polymorphisms of the IL-10 encoding gene do not play a central role in the development of complications due to BCG vaccination, although the IL10 gene, especially IL10 rs1800896 (-1082G/A) polymorphism, is known to be associated with tuberculosis risk in Europeans and North Americans.

High-risk End-stage Renal Disease Patients Converted from Conventional to Short Daily Haemodialysis

Some high-risk patients with end-stage renal disease (ESRD) cannot tolerate or do not respond to conventional haemodialysis three times per week. Sixteen high-risk ESRD patients were converted from conventional haemodialysis to short daily haemodialysis (sDHD). This consisted of 2 h daily haemofiltration or haemodiafiltration, six times per week. The dialysis response, blood pressure change, weight variations, weekly Kt/V (a measure of the adequacy of dialysis), serum phosphorus, serum albumin, haemoglobin, cardiothoracic ratio (CTR), left ventricular mass index (LVMI) and Short Form Health Survey (SF-36) quality-of-life scales were compared before and after conversion to sDHD. sDHD improved many clinical and biological variables. Weekly Kt/V increased from 4.36 ± 0.62 on conventional haemodialysis to 4.88 ± 0.41 after switching to sDHD. Blood pressure normalized, there were significant decreases in episodes of hypotension during haemodialysis, serum phosphorus concentration, CTR and LVMI, and there were significant increases in levels of serum albumin and haemoglobin. Calcium and phosphorus metabolism, and nutritional status were improved. Physical function, physical role, bodily pain, general health, vitality and mental health improved significantly.

Induction of cytotoxic T-lymphocyte responses using dendritic cells transfected with hepatocellular carcinoma mRNA

This study aims to induce an efficient expansion of cytotoxic T-lymphocytes (CTL) from peripheral blood mononuclear cells (PBMCs) using dendritic cells (DC) transfected with hepatocellular carcinoma (HCC) messenger RNA (mRNA) for adoptive immunotherapy of HCC. Dendritic cells are generated from PBMCs. HCC mRNA is isolated either from HepG-2 cells or from tumour tissue from three HCC patients, and then amplified using the polymerase chain reaction (PCR). Expansion of CTLs is achieved from PBMCs induced by DCs transfected with HCC mRNA and cytotoxicity is measured using a crystal violet staining assay. The proportion of CD3+, CD4+ and CD8+ cells is determined using flow cytometry. Dendritic cells transfected with the total HCC mRNA stimulated antigen-specific cytotoxic T-cell responses that are capable of recognising and killing autologous tumour cells in vitro. The cytotoxic activity was inhibited by treatment with anti-CD3, anti-CD8 and anti-MHC class I monoclonal antibodies, but not with anti-CD4 and MHC class II antibodies. In conclusion, HCC mRNA-transfected DCs may represent a broadly applicable vaccine strategy to induce potentially therapeutic CTL responses in HCC.

Direct molecular typing of Bordetella pertussis from nasopharyngeal specimens in China in 2012-2013

Data on the molecular epidemiology of Bordetella pertussis are limited in developing countries where whole-cell pertussis vaccines (WCVs) have been used. The aim of this study was to determine the genotypes of circulating B. pertussis in China by direct molecular typing of clinical specimens. DNA extracts of 122 nasopharyngeal swabs (NPs) positive for B. pertussis by polymerase chain reaction (PCR) (targeting IS481 and ptx-Pr) from 2012 to 2013 were used for typing using the multiple-locus variable number tandem repeat analysis (MLVA) and also by PCR-based multilocus sequence typing (MLST) of B. pertussis virulence genes (ptxP, prn, and fim3). One hundred and eight DNA extracts (89 %) generated a complete MLVA type (MT). Among the 18 MTs obtained, MT55 (52 %) and MT104 (13 %) were the most common. MT27, which is linked to the ptxP3 allele and is prevalent in many developed countries using acellular pertussis vaccines (ACVs), was only found in 7 (6 %) DNA extracts. Eighty-seven DNA extracts (71 %) produced a complete multiantigen sequence typing (MAST) type. Of them, 77 (89 %) had the ptxP1/prn1/fim3-1 allele profile. Four DNA extracts (5 %) had the ptxP3/prn2/fim3-2 profile and 3 (4 %) had the ptxP3/prn1/fim3-2 allele profile. These seven DNA extracts also harbored MT27. Our result shows that B. pertussis circulating in China was different from those found in countries where ACVs have been in use, supporting the notion that selection pressure induced by WCVs and ACVs on the bacterial population differs.

Primary and Recurrent Focal Segmental Glomerulosclerosis Closely Link to Serum Soluble Urokinase-type Plasminogen Activator Receptor Levels

BACKGROUND

Serum soluble urokinase-type plasminogen activator receptor (suPAR) is implicated in the pathogenesis of native and recurrent focal segmental glomerulosclerosis (FSGS). It is elevated in two-thirds of subjects with primary FSGS, but not in people with other glomerular diseases that can differentiate FSGS and other glomerular diseases.

METHODS

We measured the serum soluble urokinase receptor levels and determined their association with clinical and pathologic data in 86 patients with primary FSGS, 5 repeat renal biopsy FSGS, and 6 recurrent FSGS post-transplantation. Healthy controls and patients with minimal change disease and membranous nephropathy were used as controls. The suPAR levels were measured by commercial enzyme-linked immunosorbent assay kits.

RESULTS

Patients with primary FSGS (median: 4232, interquartile range 1299-9714 pg/mL) had significantly higher levels of suPAR than those of patients with minimal change disease (median: 2784 pg/mL), membranous nephropathy (median: 3478 pg/mL), and healthy individuals (median: 1994 pg/mL). There was no significant difference in suPAR levels between the 65 patients with minimal change disease and 85 patients with membranous nephropathy. The suPAR levels increased in the 5 repeated renal biopsy FSGS and 6 recurrent FSGS post-transplantation.

CONCLUSIONS

The suPAR levels were significantly but positively correlated with FSGS, not only primary FSGS but also recurrent FSGS post-transplantation, but negatively correlated with other glomerular diseases. Thus, suPAR levels can differentiate primary FSGS and other glomerular diseases.

Dopamine D1 receptor agonist A-68930 inhibits NLRP3 inflammasome activation and protects rats from spinal cord injury-induced acute lung injury

STUDY DESIGN

Randomized experimental study.

OBJECTIVES

The study aimed to investigate the therapeutic efficacy and molecular mechanisms of A-68930 in a rat model of spinal cord injury (SCI)-induced acute lung injury (ALI).

SETTING

China.

METHODS

The influences of A-68930 on the pulmonary edema, histological changes, proinflammatory cytokines levels, myeloperoxidase (MPO) activity and NLRP3 inflammasome protein expression were estimated.

RESULTS

SCI significantly promoted NLRP3 inflammasome activation, increased proinflammatory cytokine productions and MPO activity, and induced pulmonary edema and tissue damage in the SCI group as compared with the control group. A-68930 administration significantly inhibited NLRP3 inflammasome activation and reduced inflammatory cytokines levels and MPO activity. Moreover, A-68930 administration attenuated pulmonary edema and histopathology.

CONCLUSION

Our experimental findings indicated that A-68930 exhibited a protective effect on SCI-induced ALI by the alleviations of inflammatory response with the inhibition NLRP3 inflammasome activation 72 h post injury. The present study indicated that A-68930 could be a potentially efficient therapeutic strategy for the treatment of SCI-induced ALI.

[Basal cell carcinoma of prostate: a report of three cases]

To explore the clinical pathological characteristics and improve the recognition in the diagnosis and treatment of basal cell carcinoma (BCC) of prostate. Three cases of BCC of prostate were reported and the relevant literature was reviewed to investigate the diagnosis and treatment of this disease. We analyzed three cases of prostatic BCC. Their ages were within a range of 57 to 83 years. One of them complained of hematuria and two complained of dysuria. All of them presented with prostatic hyperplasia. Two of them presented with high prostate specific antigen (PSA) and one with normal PSA. Case 1 had prostate cancer invasion of bladder, rectal fascia, with lymph node metastasis, bone metastasis and lung metastases. The patient received bladder resection+bilateral ureteral cutaneous ureterostomy+lymph node dissection on November 2, 2014 . Postoperative pathological diagnosis showed BCC. Reexamination of pelvic enhanced MRI in January 8, 2015 suggested pelvic recurrence. Abdominal enhanced CT showed multiple liver metastases and pancreatic metastasis on July 11, 2015. Prostate cancer specific death occurred in October 2015. Case 2 was diagnosed as BCC in prostate biopsy on March 27, 2015. Positron emission tomography and computed tomography (PET-CT) showed pulmonary metastasis and bone metastasis. Then the patient received chemotherapy, endocrine therapy and local radiation therapy. Reexamination of PET-CT on January 11, 2016 showed that the lung metastase tumors and bone metastase tumors were larger than before. Up to January 10, 2016, the patient was still alive. Postoperative pathological changes of transurethral resection of prostate (TURP) in case 3 showed BCC might be considered. The PET-CT suggested residual prostate cancer, which might be associated with bilateral pelvic lymph node metastasis. In April 20, 2016, the review of PET-CT showed pelvic huge irregular hybrid density shadow, about 14.5 cm×10.0 cm×12.9 cm in size, and tumor recurrence was considered. Then the patient received local radiation therapy. The patient survived in the followed upon January 10, 2016. BCC of prostate is a rare subtype. Due to the local infiltrative and distant metastatic potentiality, active management is preferred and a life-long follow-up is necessary.

[Radical cystectomy in patients with pathological non-muscle invasive bladder cancer]

OBJECTIVE

Carcinoma of bladder is the most common malignancy in the urinary system in China. Most patients with this disease had non-muscle invasive bladder cancer (NMIBC) at the time of diagnosis. Radical cystectomy was indicated for patients with high risk or refractory NMIBC. We aimed to investigate the overall survival and disease-specific survival and related influence factors in patients undergoing radical cystectomy for pathological non-muscle invasive bladder cancer.

METHODS

From Jan. 2006 to Dec. 2012, a total of 164 patients with pathological non-muscle invasive bladder cancer underwent radical cystectomy in Peking University First Hospital. Clinical data were retrospectively collected.Incidence of lymph node metastasis and disease recurrence were calculated. The risk factors of disease recurrence were analyzed. Kaplan-Meier plots were used to estimate the overall survival and cancer-specific survival. Multivariate Cox regression analysis was used to evaluate the prognostic factors for survival.

RESULTS

Of all the patients included, 159 had T1 disease, and 5 had CIS only. The median follow-up duration was 46.5 months (range: 7-99 months). Fourteen patients were lost during the follow-up. Lymph node metastasis was noted in 6 patients (3.7%), 4 patients had N1 disease, one patient had N2 disease, and one patient had N3 disease. Disease recurrence occurred in 16 patients (9.8%).The most common recurrence sites were the liver, bones, and lungs. The 5-year overall survival and disease-specific survival for all the patients were 85% and 91%, respectively. The patients who underwent pelvic lymph node dissection showed a better prognosis in terms of disease-specific survival than those without (P=0.012). Patients with recurrence harbored a significant poorer survival (P<0.001). According to univariate Cox regression analysis, whether lymph node dissection was performed was an independent risk factor of disease recurrence (P=0.050, OR=2.695, 95%CI 0.999-7.271). In COX regression model, age (P=0.008, OR=1.071, 95%CI 1.018-1.126) and whether lymph node dissection was performed (P=0.011, OR=3.385, 95%CI 1.329-8.621) were related to disease-specific survival.

CONCLUSION

Patients with pathological non-muscle invasive bladder cancer underwent early radical cystectomy have a favorable prognosis, and bilateral pelvic lymph node dissection is essential for this procedure as it gains a survival benefit for the patients.

[Clinicopathological features and differential diagnosis of metanephric adenoma: a report of sixteen cases]

OBJECTIVE

To study the clinicopathological features and differential diagnosis of metanephric adenoma (MA).

METHODS

The clinicopathological data of 16 cases with MA diagnosed and treated in Peking University First Hospital from 2004 to 2016 were retrospectively analyzed, and the clinical characteristics, pathologic parameters, differential diagnosis, treatment options and prognosis of MA were analyzed with literature review.

RESULTS

The patients included 10 females and 6 males. The age of patients ranged from 14 to 83 years (mean=33.7 years). The partial nephrectomy was carried out for most patients. All cases were located in renal codex with 3 growing into the renal sinus. Histologically, the tumor was composed of tubules, papillary or glomeruloid structures and psammoma bodies were focally seen. Immunohistochemical study showed that all the cases expressed vimentin, and 94% cases expressed CD57, 63% WT1, 75% AE1/AE3, 19% cytokeratin 7 (CK7) and 13%α-methylacyl-CoA racemase (AMACR), and negative expressions for MA included CD10, neuron-specific enolase (NSE) and CD56. Follow-up information from 1 to 125 months was available in all the patients; and none of the patients showed any evidence of recurrence and metastasis.

CONCLUSION

The benign tumor characteristics of MA are not obvious for preoperative imaging diagnosis, and the diagnosis of MA should be based on the unique pathological features. Positive immunostain of CD57 is a useful indicator for MA diagnosis and differential diagnosis. The partial nephrectomy surgical treatment can achieve good clinical cure with good prognosis.

Proanthocyanidins affects the neurotoxicity of Aβ25-35 on C57/bl6 mice

OBJECTIVE

To investigate the influence of procyanidins on the impairment of memory.

MATERIALS AND METHODS

Thirty male C57bl/6 mice were divided into five groups: low, middle, and high concentration, model, and control groups. Intracerebroventricular injection of β-amyloid25-35 in C57bl/6 mice caused an impairment of learning and memory. Next day, intragastric administration of procyanidins in the treatment group mice: (lower, middle and high concentration). Hoechst staining observed apoptosis of neuronal nuclei in the hippocampus. Immunohistochemistry determined synaptic remodeling reaction and the expression level of glial inflammatory response.

RESULTS

Compared with the model group, the proportion of neuronal apoptosis decreased in the hippocampal CA1 region of the treatment group. The Synaptic (SYN) density was increased, and the level of activated astrocytes and microglia expression in the hippocampus was decreased.

CONCLUSIONS

Procyanidins have a protective influence on Aβ25-35 mice hippocampus neuron, reducing nerve cell damage and eases learning and memory deficit.

Cloning, Prokaryotic Expression and Purification of CpfS1 Gene from Arabidopsis Thaliana

CpfS1 Gene cloned from arabidopsis thaliana was expressed in Escherichia coli DH5α. A cDNA fragment about 320 bp was amplified from the total RNA of arabidopsis thaliana seeds by reverse transcription PCR (RT-PCR) with a pair of specific primers based on the sequences of the AtCpfS1 gene. The recombinant prokaryotic expression vector pET30a-AtCpfS1 was constructed by inserting the cDNA fragment encoding the mature peptide into the prokaryotic expression vector pET30a, and then transformed into E. coli DH5α. Sequence analysis showed that the fragment length was 346 bp containing a full coding region of 332 bp encoding 76 amino acid residues with a molecular mass of 21.5 kD. The SDS-PAGE electrophoresis analysis showed that the best expression was induced by 21oC and 3.6×10-3 mol/L IPTG, under which a relative molecular weight of 82.5 kD recombinant protein was produced. The nickel chelating resin was used to purify the protein in size exclusion chromatography (SEC) and the results indicated that AtCpfS1 protein was present in the form of tetramer.

Potential involvement of placental AhR in unexplained recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) is a common complication of pregnancy. Recent studies have demonstrated that the aryl hydrocarbon receptor (AhR) might play important roles in establishing and maintaining early pregnancy. In this study, we found that placental AhR protein levels were significantly lower and placental CYP1A1 mRNA levels were higher in unexplained RSA (URSA) patients than in control subjects. The results of immunohistochemical analyzes showed that placental AhR was expressed in syncytiotrophoblast cells and that the level of AhR was markedly lower in these cells in URSA subjects than in control subjects. β-Naphthoflavone (β-NF, an AhR ligand) at 5μM significantly inhibited proliferation and migration in HTR-8/SVneo cells and was associated with the activation of AhR. Moreover, overexpressing AhR in JAR cells significantly increased CYP1A1 mRNA levels and inhibited cell migration. These results indicate that AhR is highly activated in URSA placentas and that the activation of AhR in the placenta might impair trophoblast cell proliferation and migration, possibly leading to the occurrence of URSA.

Baseline characteristics and management of patients with atrial fibrillation/flutter in the emergency department: results of a prospective, multicentre registry in China

BACKGROUND/AIM

There have been several studies of atrial fibrillation (AF) over the past decades; however, data from Chinese patients are scarce. The aim of the study was therefore to describe the patient characteristics, risk profile and management strategies for Chinese AF patients presenting to emergency department (ED).

METHODS

We conducted a prospective, multicentre registry of patients with AF or atrial flutter (AFL) in China. Participants were enrolled at 20 EDs, then data regarding baseline characteristics and treatment in EDs were collected.

RESULTS

Of the 2016 Chinese patients, 1104 (54.8%) were female. Six hundred eighteen (30.7%) had paroxysmal AF, 452 (22.4%) had persistent AF and 945 (46.9%) had permanent AF. The most common comorbidity was hypertension (55.5%), followed by coronary artery disease (41.8%) and heart failure (HF, 37.4%). The prevalence of concomitant cardiovascular risk factors, such as HF and valvular heart disease, increased as AF progressed. Among the patients with non-valvular AF, 110 (12.7%) of those with CHADS2 (congestive HF, hypertension, age of 75 years and greater, diabetes mellitus and history of stroke) ≥2 were prescribed oral anticoagulants (OAC), while 119 (15.6%) of those with CHADS2 <2 received such agents. Among the 324 patients with valvular AF, 134 (41.4%) actually were treated with OAC. The international normalised ratio value was within the target range (2.0-3.0) in 96 patients only (26.4%). Moreover, a total of 16.2% of the patients received ≥1 anti-arrhythmic agents, whereas rate control agents were used more frequently (68.4%).

CONCLUSIONS

According to the present study, the risk profile and management of Chinese patients with AF/AFL differed from that observed in previous studies. The use of OAC inadequately deviate from current guidelines.

The effect of treadmill training and N-acetyl-l-cysteine intervention on biogenesis of cytochrome c oxidase (COX)

Mitochondrial biogenesis refers to increased content of mitochondria, which has been shown to be promoted by aerobic exercise. During this process, oxidative stress is considered the essential initiator. Even though some studies have addressed the issue as to whether antioxidants would hamper the effects of exercise on mitochondrial biogenesis, no consensus has been achieved. Therefore, the purpose of the present study was to investigate the effects of exercise and antioxidant intervention on mitochondrial biogenesis, as well as COX biogenesis. Thirty-two clean-grade male ICR mice were randomly assigned to a control group (Con), exercise group (Ex), N-acetyl-l-cysteine group (NAC), or NAC plus exercise group (NEx). The NAC and NEx groups were injected with NAC (0.1 mg/g/2 days) intraperitoneally for 3 weeks, whereas the Con and Ex groups were administered saline for the same period of time. Mice assigned to Ex and NEx groups started exercise training 1 week before drug intervention was initiated. After 1 week of acclimatization, the mice were allowed to run at a speed of 28 m/min for 60 min, 6 days a week. The results showed that exercise training caused an increase in mRNA and protein levels of COXIV, whereas NAC intervention lowered the two so significantly that even exercise training could not reverse the effect of NAC intervention. Our data suggest that even though antioxidant intervention could alleviate oxidative damage caused by exercise, it was not necessarily beneficial for mitochondrial biogenesis.

Association of branched-chain amino acids with coronary artery disease: A matched-pair case-control study

BACKGROUND AND AIM

Several recent studies have found an independent relationship between levels of plasma branched-chain amino acids (BCAAs) and risk factors for coronary artery disease (CAD); however, few studies have investigated the associations of BCAAs with CAD and the risk of cardiovascular events. Therefore, the aim of this study was to investigate the relationship between BCAAs and CAD.

METHODS AND RESULTS

We studied 143 patients with CAD diagnosed by coronary angiography at Beijing Hospital (Beijing, China) during 2008-2011. Apparently healthy control individuals (n = 286) and the patients with CAD were matched (2:1 ratio) by age and gender. The healthy control individuals were selected at random from a set of subjects who attended an annual physical examination at the same hospital in 2011. Conditional logistic regression models were used to evaluate the associations between measured variables and CAD. After multivariate adjustment for traditional CAD risk factors, each one-standard-deviation increase in BCAA concentration was associated with an approximately twofold increase in the risk of CAD (odds ratio = 1.63, 95% confidence interval (CI): 1.21-2.20, P = 0.001). As compared with subjects in the lowest quartile of BCAA levels, the odds ratios (95% CIs) for CAD risk in subjects belonging to quartiles 2, 3, and 4 were 1.65 (0.75-3.61), 2.04 (0.92-4.53), and 3.86 (1.71-8.69), respectively (P trend = 0.01).

CONCLUSION

Our results demonstrate that BCAAs are significantly related to CAD development. This relationship is independent of diabetes, hypertension, dyslipidemia, and body mass index.

Silencing FKBP38 gene by siRNA induces activation of mTOR signaling in goat fetal fibroblasts

FKBP38 (also known as FKBP8) is a unique member of the FK506-binding protein (FKBP) family, and its role is controversial because it acts as an upstream regulator of the mTOR signaling pathway, which controls cell growth, proliferation, and differentiation. This study aimed to explore the role of FKBP38 in the activation of mTOR signaling in Cashmere goat (Capra hircus) fetal fibroblasts. To construct a Cashmere goat FKBP38 siRNA eukaryotic expression vector that targets FKBP38 mRNA, we designed shRNA based on the gene sequence deposited in GenBank (accession No. JF714970) and synthesized a DNA fragment encoding the shRNA. The DNA fragment was inserted into the pRNAT-U6.1/Neo vector to construct an expression vector of shRNA, which was labeled pRNAT-FKBP38-shRNA. The recombinant plasmid was used to transfect Cashmere goat fetal fibroblasts (GFb) using lipofectamine™2000. We found that cells were successfully transfected with pRNAT-U6.1/Neo-FKBP38-shRNA. Green fluorescence could be observed in cells following 48-h transfection. Proteins were then isolated from GFbs transfected with pRNAT-FKBP38-shRNA and from control cells, and protein expression was analyzed by western blot. Expression of FKBP38 decreased and mTOR signaling was activated, which induced the phosphorylation of mTOR, S6, and 4EBP1. Thus, FKBP38 gene-silencing activates mTOR signaling in goat cells.

CuInP₂S₆ Room Temperature Layered Ferroelectric

We explore ferroelectric properties of cleaved 2-D flakes of copper indium thiophosphate, CuInP2S6 (CITP), and probe size effects along with limits of ferroelectric phase stability, by ambient and ultra high vacuum scanning probe microscopy. CITP belongs to the only material family known to display ferroelectric polarization in a van der Waals, layered crystal at room temperature and above. Our measurements directly reveal stable, ferroelectric polarization as evidenced by domain structures, switchable polarization, and hysteresis loops. We found that at room temperature the domain structure of flakes thicker than 100 nm is similar to the cleaved bulk surfaces, whereas below 50 nm polarization disappears. We ascribe this behavior to a well-known instability of polarization due to depolarization field. Furthermore, polarization switching at high bias is also associated with ionic mobility, as evidenced both by macroscopic measurements and by formation of surface damage under the tip at a bias of 4 V-likely due to copper reduction. Mobile Cu ions may therefore also contribute to internal screening mechanisms. The existence of stable polarization in a van-der-Waals crystal naturally points toward new strategies for ultimate scaling of polar materials, quasi-2D, and single-layer materials with advanced and nonlinear dielectric properties that are presently not found in any members of the growing "graphene family".

Arabidopsis thaliana SEPALLATA3 protein prokaryotic expression and purification

SEPALLATA3 (SEP3) can be attributed to E class gene of the ABCE model of floral organ development. In order to reveal how SEP3 proteins form polymers, and the relationship between the polymers and their biological functions, the experiments of Arabidopsis thaliana AtSEP3 protein soluble expression in vitro were performed to construct a vector of prokaryotic expression, and investigate induced expression of recombinant proteins in Escherichia coli cells. The protein soluble expression was analyzed through the aspects of different protein domains, induction time, induction temperature, etc. Different structural domains and expression conditions were screened, and 0.1% IPTG inducing at 22 oC for 15 h was estimated as an optimal expression strategy. The nickel chelating resin was used to purify the protein in size exclusion chromatography (SEC) and the results indicated that AtSEP3 protein was present in the form of tetramer.

Vibrio cholerae ghosts elicit the production of soluble immunostimulatory factors and prevent development of Chlamydia infection (INM3P.408)

Infections by the obligate intracellular pathogen Chlamydia trachomatis cause infertility in women of childbearing age. Currently infections caused by the pathogen are treated with antimicrobial therapy. Bacterial ghosts offer a cost-effective, long-term, protective therapy as vaccine delivery vectors. In the present study we tested the hypothesis that factors contained in culture supernatant exhibit anti-chlamydial activity. THP-1 monocytes were differentiated into macrophages (Mdm) by incubating with phorbol myristate acetate (PMA). Activated Mdm were pulsed with Vibrio cholerae ghosts (VCG) for 24 h, followed by the addition of murine splenocytes for an additional 48 h. After 72 h the supernatant was collected and assayed for cytokine concentration. Samples presented observable levels of immunostimulatory factors necessary for containing or clearing infections with chlamydia. Following these assay results, Chlamydia pneumonia (MoPn) elementary bodies (EBs) were suspended in VCG-pulsed THP-1 Mdm supernatant (conditioned media) and used to culture HeLa cells. As a positive control, MoPn was suspended in Earle’s MEM - a medium used for HeLa cell culture. Immunostimulatory factors contained in the conditioned media prevented the development of Chlamydia infection forming units (5.87%) vs. our positive control (94.1%). These results indicate that immunostimulatory factors induced by VCG confer protective immunity against the development cycle of Chlamydia.

Sirolimus for treatment of autosomal-dominant polycystic kidney disease: a meta-analysis of randomized controlled trials

BACKGROUND

Autosomal-dominant polycystic kidney disease (ADPKD) is the most common form of cystic kidney disease. The mammalian target of rapamycin (mTOR) pathway is associated with progressive kidney enlargement. The drug sirolimus suppresses mTOR signaling but plays an uncertain role in the treatment of ADPKD. The objective of our study was to conduct a meta-analysis of randomized controlled trials (RCTs) to present an objective appraisal of the efficacy and safety of sirolimus therapy in patients with ADPKD.

METHODS

We conducted a meta-analysis of RCTs performed in adults with ADPKD, and compared the effect of sirolimus on total kidney volume (TKV), glomerular filtration rate (GFR), cyst volume, and daily urinary protein excretion. Safety was evaluated based on analysis of blood pressure, lipid profile, complete blood count, infection, and other reported adverse events.

RESULTS

Four RCTs were included. The sirolimus therapy group had smaller TKV than the control group. The mean difference (MD) of TKV post-treatment compared with the control group was -234.74 (P = .01). However, GFR did not reach a statistically significant difference between groups. Standard mean difference (SMD) of GFR after therapy was 0.24 (95% confidence interval [CI], 0.05-0.52; P = .11), but sirolimus seemed to increase urine protein excretion (P = .002). There was no statically significant difference in leukocytes, hemoglobin, platelets, and blood pressure between groups. Aphthous stomatits and pharyngitis are reported more commonly in the sirolimus therapy group compared with the control group (P < .000001).

CONCLUSIONS

In ADPKD patients, treatment with sirolimus is safe and can effectively slow kidney growth, but it seems not to slow down the decrease of GFR.

Nasal endoscopic findings and nasal symptoms in patients with asthma: a clinical study from a rhinological perspective

OBJECTIVE

Allergic rhinitis (AR), non-allergic rhinitis (NAR), chronic rhinosinusitis with nasal polyps (CRSwNP), and chronic rhinosinusitis without nasal polyps (CRSsNP) occur frequently in asthmatic patients. We evaluated nasal symptoms and nasal endoscopic findings in patients with asthma and correlated them to asthma severity.

METHODS

Subjects (n=150) with asthma completed questionnaires designed to provide information related to asthma and nasal disease. Patients were divided into four groups based on asthma severity. Pulmonary function tests, skin-prick tests (SPTs) and nasal endoscopy were performed on every patient. Clinical findings were compared in asthma patients by rhinologists.

RESULTS

The total incidence of AR, NAR, CRSwNP and CRSsNP in these patients with asthma was 76%. By using Fisher's Exact Test, there was no statistical significance between asthma severity and the incidence of AR, NAR, CRSwNP and CRSsNP (P=0.311). There was a significant difference in the total nasal symptoms score among subjects with different grades of asthma (P=0.002). However, there were no significant differences in the total Lund-Kennedy endoscopic score (LKS) (P=0.736). The nasal endoscopic scores were significantly correlated at a high degree with the nasal symptoms score (P=0.000). A significant correlation was found between the nasal endoscopic score and the duration of asthma in the patients with different grades of asthma (P<0.05).

CONCLUSIONS

The relationship between rhinitis and asthma is complex. Nasal airways should become part of standard clinical assessment and follow-up in patients with asthma.

Analysis of Bordetella pertussis clinical isolates circulating in European countries during the period 1998-2012

Despite more than 50 years of vaccination, pertussis is still an endemic disease, with regular epidemic outbreaks. With the exception of Poland, European countries have replaced whole-cell vaccines (WCVs) by acellular vaccines (ACVs) in the 1990s. Worldwide, antigenic divergence in vaccine antigens has been found between vaccine strains and circulating strains. In this work, 466 Bordetella pertussis isolates collected in the period 1998–2012 from 13 European countries were characterised by multi-locus antigen sequence typing (MAST) of the pertussis toxin promoter (ptxP) and of the genes coding for proteins used in the ACVs: pertussis toxin (Ptx), pertactin (Prn), type 2 fimbriae (Fim2) and type 3 fimbriae (Fim3). Isolates were further characterised by fimbrial serotyping, multi-locus variable-number tandem repeat analysis (MLVA) and pulsed-field gel electrophoresis (PFGE). The results showed a very similar B. pertussis population for 12 countries using ACVs, while Poland, which uses a WCV, was quite distinct, suggesting that ACVs and WCVs select for different B. pertussis populations. This study forms a baseline for future studies on the effect of vaccination programmes on B. pertussis populations.

Differentially expressed genes in the liver of lean and fat chickens

This study aimed to investigate gene expression in the chicken liver for lean and fat broiler lines. Birds used in this study were 2 and 4 weeks of age; they were derived from the 14th generation of Northeast Agricultural University broiler lines, which were divergently selected based on abdominal fat content. Chicken Genome Arrays were used to screen differentially expressed genes in the liver tissue from lean and fat birds. At 2 and 4 weeks of age, 770 and 452 genes were differentially expressed between the 2 lines, respectively. The differentially expressed genes were involved in Wnt, insulin signaling, and cell cycle pathways. At 2 and 4 weeks, 42 shared, differentially expressed genes were revealed by the analysis. We speculate that these genes might regulate chicken lipid metabolism.

LKB1 reduces ROS-mediated cell damage via activation of p38

Liver kinase B1 (LKB1, also known as serine/threonine kinase 11, STK11) is a tumor suppressor mutated in Peutz-Jeghers syndrome and in a variety of sporadic cancers. Herein, we demonstrate that LKB1 controls the levels of intracellular reactive oxygen species (ROS) and protects the genome from oxidative damage. Cells lacking LKB1 exhibit markedly increased intracellular ROS levels, excessive oxidation of DNA, increased mutation rates, and accumulation of DNA damage, which are effectively prevented by ectopic expression of LKB1 and by incubation with antioxidant N-acetylcysteine (NAC). The role of LKB1 in suppressing ROS is independent of AMPK, a canonical substrate of LKB1. Instead, under the elevated ROS, LKB1 binds to and maintains the activity of cdc42-PAK1 (p21 activated kinase 1) complex, which triggers the activation of p38 and its downstream signaling targets, such as ATF-2, thereby enhancing the activity of SOD-2 and catalase, two antioxidant enzymes that protect the cells from ROS accumulation, DNA damage, and loss of viability. Our results provide a new paradigm for a non-canonical tumor suppressor function of LKB1 and highlight the importance of targeting ROS signaling as a potential therapeutic strategy for cancer cells lacking LKB1.

Effects of rifampicin on osteogenic differentiation and proliferation of human mesenchymal stem cells in the bone marrow

This study was designed to investigate the effect of different concentrations of rifampicin on osteogenic differentiation and proliferation of mesenchymal stem cells (MSCs) in human bone marrow. Rifampicin treatment at 0, 4, 8, 16, 32, 64, and 128 mg/mL was applied throughout the whole process, from stromal cells purified from human bone marrow to differentiated bone cells. The effect of rifampicin on MSC proliferation was determined using the MTT assay. The effect of rifampicin on the expressions of type I collagen (COL1A1), osteopontin/bone Gla protein (OPN/BGP), and alkaline phosphatase (ALP) in human osteoblast cells were determined by real-time polymerase chain reaction, and the expressions of COL1A1, OPN/BGP, and the runt-related transcription factor (RUNX2) were determined by Western blot. Results showed that the proliferation of MSCs was significantly inhibited when the rifampicin concentration exceeded 32 mg/mL. In addition, increased rifampicin concentrations inhibited the formation of calcium nodules, OPN/BGP, and COL1A1 in osteoblasts after 28 days of induction. The RNA expressions of OPN/BGP, COL1A1, and ALP were significantly downregulated compared to those of the control group in osteoblasts after induction. The protein expressions of RUNX2, COL1A1, and OPN/BGP were also significantly downregulated compared to those of the control group after induction. In conclusion, rifampicin at exorbitant concentration exerts adverse effects on the proliferation of MSCs in human bone marrow and the differentiation of osteoblasts.

Investigations into the emergence of pertactin-deficient Bordetella pertussis isolates in six European countries, 1996 to 2012

Pathogen adaptation has been proposed to contribute to the resurgence of pertussis. A striking recent example is the emergence of isolates deficient in the vaccine component pertactin (Prn). This study explores the emergence of such Prn-deficient isolates in six European countries. During 2007 to 2009, 0/83 isolates from the Netherlands, 0/18 from the United Kingdom, 0/17 Finland, 0/23 Denmark, 4/99 Sweden and 5/20 from Norway of the isolates collected were Prn-deficient. In the Netherlands and Sweden, respectively 4/146 and 1/8 were observed in a later period (2010–12). The Prn-deficient isolates were genetically diverse and different mutations were found to inactivate the prn gene. These are indications that Prn-deficiency is subject to positive selective pressure. We hypothesise that the switch from whole cell to acellular pertussis vaccines has affected the balance between ‘costs and benefits’ of Prn production by Bordetella pertussis to the extent that isolates that do not produce Prn are able to expand. The absence of Prn-deficient isolates in some countries may point to ways to prevent or delay the spread of Prn-deficient strains. In order to substantiate this hypothesis, trends in the European B. pertussis population should be monitored continuously.

K63-linked ubiquitination of FANCG is required for its association with the Rap80-BRCA1 complex to modulate homologous recombination repair of DNA interstand crosslinks

DNA interstrand crosslinks (ICLs) are extremely deleterious lesions that are repaired by homologous recombination (HR) through coordination of Fanconi anemia (FA) proteins and breast cancer susceptibility gene 1 (BRCA1) product, but the exact role these proteins have remains unclear. Here we report that FANCG was modified by the addition of lysine63-linked polyubiquitin chains (K63Ub) in response to DNA damage. We show that FANCG K63Ub was dispensable for monoubiquitination of FANCD2, but was required for FANCG to interact with the Rap80-BRCA1 (receptor-associated protein 80-BRCA1) complex for subsequent modulation of HR repair of ICLs induced by mitomycin C. Mutation of three lysine residues within FANCG to arginine (K182, K258 and K347, 3KR) reduced FANCG K63Ub modification, as well as its interaction with the Rap80-BRCA1 complex, and therefore impeded HR repair. In addition, we demonstrated that K63Ub-modified FANCG was deubiquitinated by BRCC36 complex in vitro and in vivo. Inhibition of BRCC36 resulted in increased K63Ub modification of FANCG. Taken together, our results identify a new role of FANCG in HR repair of ICL through K63Ub-mediated interaction with the Rap80-BRCA1 complex.

Beneficial effects of statins on outcomes in pneumonia: a systematic review and meta-analysis

OBJECTIVES

There exist reports that statin treatment has beneficial effects for patients with pneumonia. The objective of this study was to evaluate whether the available published data support that statins as adjunctive therapy could reduce mortality associated with pneumonia and, thus, help to assess whether a randomized controlled study is warranted.

MATERIALS AND METHODS

A meta-analysis of observational studies such as cohort studies and case-control studies identified in Pubmed, Scopus, EMBASE, the Cochrane Central Register of Controlled Trials and Clinicaltrials.gov. Eligible patients were adults with pneumonia. Studies that reported mortality of pneumonia grouped by statins usage were included. Data was analyzed and pooled using Revman 5.1.

RESULTS

Fourteen studies with 269,739 participants were included in this study. Pooled analysis showed that statin treatment was associated with lower 30-day mortality, with an OR of 0.44 (95% CI, 0.29-0.67), and an adjusted OR of 0.59 (95% CI 0.48-0.73, NNT30d = 19). Statin therapy was also associated with lower long-term (> 30 days) mortality, with an OR of 0.49 (95% CI, 0.29-0.84) and an adjusted OR of 0.65 (95% CI, 0.51-0.82, NNTlong-term = 15). For pneumonia inpatients, the raw data demonstrated no significant benefit from statin therapy (OR = 0.86, 95% CI, 0.56-1.34). Adjusted data showed a marginal benefit (adjusted OR = 0.89, 95% CI, 0.81-0.97, NNTinpatient = 230). Subgroup analysis revealed that current statin users might have better outcomes than recent or past statins users.

CONCLUSIONS

This meta-analysis supports that patients who happen to be receiving statin therapy have less mortality from pneumonia. However, it remains unclear whether initiation of statins at time of diagnosis is beneficial. There is only modest evidence to support the value of a well-designed randomized controlled clinical trial.

Liver kinase B1 regulates the centrosome via PLK1

Liver kinase B1 (LKB1) is a tumor suppressor mutationally inactivated in Peutz-Jeghers syndrome (PJS) and various sporadic cancers. Although LKB1 encodes a kinase that possesses multiple functions, no individual hypothesis posed to date has convincingly explained how loss of LKB1 contributes to carcinogenesis. In this report we demonstrated that LKB1 maintains genomic stability through the regulation of centrosome duplication. We found that LKB1 colocalized with centrosomal proteins and was situated in the mitotic spindle pole. LKB1 deficiency-induced centrosome amplification was independent of AMP-activated protein kinase (AMPK), a well-defined substrate of LKB1. Cells lacking LKB1 exhibited an increase in phosphorylated and total Polo-like kinase 1 (PLK-1), NIMA-related kinase 2 (NEK2), and ninein-like protein (NLP). Overexpression of active PLK1 (T210D) reversed the inhibition of LKB1 on centrosome amplification. In contrast, depletion of PLK1 with siRNA or suppression of PLK1 kinase activity with BTO-1 (5-Cyano-7-nitro-2-benzothiazolecarboxamide-3-oxide) abrogated LKB1 deficiency-induced centrosome amplification. We further characterized that LKB1 phosphorylated and activated AMPK-related kinase 5 (NUAK1 or ARK5) that in turn increased the phosphorylation of MYPT1, enhanced the binding between MYPT1-PP1 and PLK1, and conferred an effective dephosphorylation of PLK1. More importantly, we noted that LKB1-deficient cells exhibited multiple nuclear abnormalities, such as mitotic delay, binuclear, polylobed, grape, large, and micronuclear. Immediate depletion of LKB1 resulted in the accumulation of multiploidy cells. Expression of LKB1 is reversely correlated with the levels of PLK1 in human cancer tissues. Thus, we have uncovered a novel function of LKB1 in the maintenance of genomic stability through the regulation of centrosome mediated by PLK1.

Room-temperature antiferromagnetic memory resistor

The bistability of ordered spin states in ferromagnets provides the basis for magnetic memory functionality. The latest generation of magnetic random access memories rely on an efficient approach in which magnetic fields are replaced by electrical means for writing and reading the information in ferromagnets. This concept may eventually reduce the sensitivity of ferromagnets to magnetic field perturbations to being a weakness for data retention and the ferromagnetic stray fields to an obstacle for high-density memory integration. Here we report a room-temperature bistable antiferromagnetic (AFM) memory that produces negligible stray fields and is insensitive to strong magnetic fields. We use a resistor made of a FeRh AFM, which orders ferromagnetically roughly 100 K above room temperature, and therefore allows us to set different collective directions for the Fe moments by applied magnetic field. On cooling to room temperature, AFM order sets in with the direction of the AFM moments predetermined by the field and moment direction in the high-temperature ferromagnetic state. For electrical reading, we use an AFM analogue of the anisotropic magnetoresistance. Our microscopic theory modelling confirms that this archetypical spintronic effect, discovered more than 150 years ago in ferromagnets, is also present in AFMs. Our work demonstrates the feasibility of fabricating room-temperature spintronic memories with AFMs, which in turn expands the base of available magnetic materials for devices with properties that cannot be achieved with ferromagnets.

Development of Methanoculleus-specific real-time quantitative PCR assay for assessing methanogen communities in anaerobic digestion

AIM

To develop a Methanoculleus-specific real-time quantitative PCR (RT-qPCR) assay with high coverage and specificity for the analysis of methanogenic populations in anaerobic digestion.

METHODS AND RESULTS

A Methanoculleus-specific primer/probe set for RT-qPCR was designed in this study based on all Methanoculleus 16S rRNA gene sequences in Ribosomal Database Project (RDP) according to TaqMan chemistry. The newly designed primer/probe set was shown to have high coverage and specificity by both in silico and experimental analyses. Amplification efficiency of the Methanoculleus-specific primer/probe set was determined to be ideal for RT-qPCR applications. Subsequent field testing on anaerobic digesters showed that results from RT-qPCR were consistent with those from clone library analysis, validating the accuracy of the RT-qPCR assay.

CONCLUSIONS

The Methanoculleus-specific RT-qPCR assay designed in this study can serve as a rapid and effective tool for the quantification of Methanoculleus populations in anaerobic digestion.

SIGNIFICANCE AND IMPACT OF THE STUDY

Methanoculleus populations represent important members of archaeal communities in methanogenic processes, necessitating the need to develop effective tools to monitor Methanoculleus population abundance. The RT-qPCR developed in this study provides an essential tool for the quantification of Methanoculleus populations in anaerobic digestion and for the understanding of the functions of these methanogens in anaerobic biotransformation.

Atomic force microscopic investigation of respiratory syncytial virus infection in HEp-2 cells

Respiratory syncytial virus (RSV) primarily causes bronchiolitis and pneumonia in infants. In spite of intense research, no safe and effective vaccine has been developed yet. For understanding its pathogenesis and development of anti-RSV drugs/therapeutics, it is indispensable to study the RSV-host interaction. Although, there are limited studies using electron microscopy to elucidate the infection process of RSV, to our knowledge, no study has reported the morphological impact of RSV infection using atomic force microscopy. We report the cytoplasmic and nuclear changes in human epidermoid cell line type 2 using atomic force microscopy. Human epidermoid cell line type 2 cells, grown on cover slips, were infected with RSV and fixed after various time periods, processed and observed for morphological changes using atomic force microscopy. RSV infected cells showed loss of membrane integrity, with degeneration in the cellular content and cytoskeleton. Nuclear membrane was disintegrated and nuclear volume was decreased. The chromatin of the RSV infected cells was condensed, progressing towards degeneration via pyknosis and apoptosis. Membrane protrusions of ~150-200 nm diameter were observed on RSV infected cells after 6 h, suggestive of prospective RSV budding sites. To our knowledge, this is the first study of RSV infection process using atomic force microscopy. Such morphological studies could help explore viral infection process aiding the development of anti-RSV therapies.

The anti-tumoral efficacy of a docetaxel-loaded liposomal drug delivery system modified with transferrin for ovarian cancer

To reduce the toxic effect on normal cells and improve the treatment effects of docetaxel, a novel transferrin modified docetaxel-loaded long circulating liposome for ovarian tumor was established for the first time. The transferrin-modified long-circulating liposomes loaded with docetaxel (TF-LP-DOC) were prepared by the post-insertion method and exhibited excellent characteristics in terms of particle size, encapsulation efficiency and stability. We investigated the targeting efficiencies of liposomes by the cellular uptake in vitro and biodistribution in vivo, and identified the therapeutic effects using cytotoxicity experiment (in vitro)and tumor growth inhibition (in vivo) on ovarian cancer. The in vitro and in vivo results showed that TF-LP-DOC were successfully established and presented an enhanced targeting ability. With decreased side effect and improved anti-tumor efficacy of chemotherapeutic drugs, TF-LP-DOC proved itself to be a very promising tumor targeted drug delivery system.

Piperlongumine induces autophagy by targeting p38 signaling

Piperlongumine (PL), a natural product isolated from the plant species Piper longum L., can selectively induce apoptotic cell death in cancer cells by targeting the stress response to reactive oxygen species (ROS). Here we show that PL induces cell death in the presence of benzyloxycarbonylvalyl-alanyl-aspartic acid (O-methyl)-fluoro-methylketone (zVAD-fmk), a pan-apoptotic inhibitor, and in the presence of necrostatin-1, a necrotic inhibitor. Instead PL-induced cell death can be suppressed by 3-methyladenine, an autophagy inhibitor, and substantially attenuated in cells lacking the autophagy-related 5 (Atg5) gene. We further show that PL enhances autophagy activity without blocking autophagy flux. Application of N-acetyl-cysteine, an antioxidant, markedly reduces PL-induced autophagy and cell death, suggesting an essential role for intracellular ROS in PL-induced autophagy. Furthermore, PL stimulates the activation of p38 protein kinase through ROS-induced stress response and p38 signaling is necessary for the action of PL as SB203580, a p38 inhibitor, or dominant-negative p38 can effectively reduce PL-mediated autophagy. Thus, we have characterized a new mechanism for PL-induced cell death through the ROS-p38 pathway. Our findings support the therapeutic potential of PL by triggering autophagic cell death.

Enhanced tumor accumulation and cellular uptake of liposomes modified with ether-bond linked cholesterol derivatives

Novel liposomal formulations based on cholesterol modification had been designed previously by our lab, but we found them with a poor stability and short half-life, especially in blood circulation. The results might be attributed to the hydrolysis of ester linked cholesterol derivatives by esterase in plasma. Thus, in this study, we newly synthesized ether-linked cholesterol derivatives and compared them to other preparations. A comparison with the substrate cholesterol-PEG2000-maleimide showed that ether-linked cholesterol-PEG2000-maleimide could relatively maintain integrity in serum, with only a small mottle emerging on TLC (thin-layer chromatography) plates through the experiment. Then a cell-penetrating peptide TAT was attached to the distal end of CHO-PEG2000 to prepare liposomes and to further evaluate the two cholesterol derivatives. Optimized liposomes (65:35, lipid/cholesterol, molar ratio) composed of 3% CHO-PEG2000 and 3% CHO-PEG2000-TAT showed good stability in 50%FBS (fetal bovine serum). In vitro experiments showed that as incubation time prolonged, ether-linked-TAT LIP showed a 3.67-fold higher uptake amount than ester-linked-TAT LIP. In vivo, ether-linked-TAT LIP accumulated better in tumors and had a 40% higher cellular uptake amount. Altogether, we could conclude that our newly ether-linked cholesterol derivatives possessed better stability especially in blood circulation which led to increased tumor cellular uptake in vitro and in vivo. Our study may offer a better way in cholesterol modification to prepare functionalized liposomes.