Severe brain damage in premature infants associated with postnatal infection

AIM

This study examined clinical features and neuroimaging characteristics of severe brain damage in premature infants with postnatal infection.

METHODS

We retrospectively analyzed clinical data of two preterm infants who developed extensive encephalomalacia secondary to postnatal infection.

RESULTS

Two premature boys experienced serious postnatal infection at about 3 weeks after birth; the infection was characterized by lethargy, apnea, increased CRP, severe bilateral pneumonia, positive sputum culture for multidrug-resistant bacteria, and mild changes of cerebrospinal fluid. Both infants required ventilation and antibiotic therapy. While both infants survived, a very extensive encephalomalacia was documented by serial cranial ultrasound, MRI and CT scans 3 to 4 weeks after postnatal infection. Their mothers had no premature ruptures of membranes and no signs of antenatal infection, suggesting potential postnatal infection in the infants.

CONCLUSION

More studies are needed to better understand the underlying mechanism of encephalomalacia associated with postnatal infection. To facilitate early diagnosis and effective treatment, cranial ultrasound scans should be done routinely in premature infants with serious postnatal infection.

DNA methylation patterns of peroxisome proliferator-activated receptor gamma gene associated with liver fibrosis and inflammation in chronic hepatitis B

Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a nuclear receptor that regulates gene expression of inflammatory mediators in liver injury. Hepatitis B virus (HBV) suppresses the PPAR gamma-mediated transactivation in liver cancerous cell lines. However, the role of PPAR gamma in patients with chronic HBV infection has not fully demonstrated. Our present study was firstly to determine the clinical relevance of peripheral PPAR gamma mRNA levels in chronic hepatitis B (CHB) patients, and then, the DNA methylation of PPAR gamma promoter was investigated. Peripheral blood mononuclear cells (PBMCs) were isolated from 91 CHB patients and 18 healthy controls. The mRNA level of PPAR gamma was determined by quantitative real-time PCR; meanwhile, the CpG island methylation was assessed by methylation-specific PCR. CHB patients showed significantly lower mRNA level of PPAR gamma than healthy controls (P = 0.005). The mRNA level was decreased in HBV-DNA-positive group than HBV-DNA-negative group (P = 0.041). Interaction analysis demonstrated that the DNA methylation pattern was responsible for the suppression of peripheral PPAR gamma transcription in CHB patients (P = 0.003). Furthermore, the hypermethylation of PPAR gamma gene promoter was significantly associated with liver inflammation and fibrosis in CHB. In conclusion, DNA methylation patterns were responsible for the decreased mRNA level of peripheral PPAR gamma in CHB patients. Liver inflammation and fibrosis were found to be associated with hypermethylation of PPAR gamma promoter.

Seroprevalence of Chlamydia psittaci infection in market-sold adult chickens, ducks and pigeons in north-western China

Chlamydia psittaci, the agent of psittacosis in humans, infects a wide range of avian species. To assess the risk of psittacosis posed by domestic birds in the urban environment, the prevalence of C. psittaci antibodies in 413 chickens (Gallus domesticus; 305 caged and 108 free-range), 334 ducks (Anas spp.; 111 caged and 223 free-range) and 312 pigeons (Columba livia) in Lanzhou, north-western China, was detected using the indirect haemagglutination assay. The specific antibodies were found in sera of 55 (13.32 %) chickens, 130 (38.92 %) ducks and 97 (31.09 %) pigeons. Statistical analysis showed that the seroprevalence of C. psittaci infection in chickens was significantly lower than that in ducks and pigeons (P<0.05). The C. psittaci seroprevalence in caged and free-range chickens was 7.54 % and 29.63 %, respectively, and the difference was statistically significant (P<0.05). The C. psittaci seroprevalence in caged and free-range ducks was 26.13 % and 45.29 %, respectively (P<0.05). To our knowledge, this is the first study indicating the presence of C. psittaci infection in market-sold chickens, ducks and pigeons in north-western China. Close contact with these birds is associated with a risk of zoonotic transmission of C. psittaci. Public education should be implemented to reduce the risk of avian to human transmission of such a pathogenic agent.

Assessment of genotoxic effects of flumorph by the comet assay in mice organs

The present study investigated the genotoxic effects of flumorph in various organs (brain, liver, spleen, kidney and sperm) of mice. The DNA damage, measured as comet tail length (µm), was determined using the alkaline comet assay. The comet assay is a sensitive assay for the detection of genotoxicity caused by flumorph using mice as a model. Statistically significant increases in comet assay for both dose-dependent and duration-dependent DNA damage were observed in all the organs assessed. The organs exhibited the maximum DNA damage in 96 h at 54 mg/kg body weight. Brain showed maximum DNA damage followed by spleen > kidney > liver > sperm. Our data demonstrated that flumorph had induced systemic genotoxicity in mammals as it caused DNA damage in all tested vital organs, especially in brain and spleen.

Deaths of tuberculosis patients in urban China: a retrospective cohort study

BACKGROUND

The case-fatality rate for tuberculosis (TB) remains high in China, whereas risk factors for deaths among TB cases are still unclear.

DESIGN

This was a retrospective cohort study of all pulmonary TB patients registered in four districts of Shanghai from 2004 to 2008. Data were derived from the China National TB Surveillance System. A total of 4271 patients were followed up in communities. Data were analysed using Cox regression.

RESULTS

The percentage of all-cause deaths in the study population was 15% 2-6 years after the most recent TB diagnosis. TB was responsible for only 17% of all deaths; male sex was significantly associated with all-cause deaths. After adjustment for sex, age and treatment history, four factors were significantly and independently associated with increased risk of death: psychopathy, chronic bronchitis, cancer and the presence of multiple diseases. TB was responsible for 7.2 potential years of life lost (PYLL); PYLL was higher in females (8.2) than males (5.3).

CONCLUSIONS

TB remains a significant problem in urban China. Implementation of improved clinical management, prevention strategies and other public health programmes should target TB patients with chronic conditions, particularly those with multiple diseases.

Observation of two new N* resonances in the decay ψ(3686)→ppπ0

Based on 106×10(6)ψ(3686) events collected with the BESIII detector at the BEPCII facility, a partial wave analysis of ψ(3686)→ppπ0 is performed. The branching fraction of this channel has been determined to be B(ψ(3686)→ppπ0)=(1.65±0.03±0.15)×10(-4). In this decay, 7 N* intermediate resonances are observed. Among these, two new resonances, N(2300) and N(2570) are significant, one 1/2+ resonance with a mass of 2300(-30-0)(+40+109)  MeV/c2 and width of 340(-30-58)(+30+110)  MeV/c2, and one 5/2- resonance with a mass of 2570(-10-10)(+19+34)  MeV/c2 and width of 250(-24-21)(+14+69)  MeV/c2. For the remaining 5 N* intermediate resonances [N(1440), N(1520), N(1535), N(1650) and N(1720)], the analysis yields mass and width values that are consistent with those from established resonances.

Establishment of Eimeria tenella (local isolate) in chicken embryos

Development of an in vitro Eimeria (E.) tenella model could be valuable as a tool for vaccine, coccidiostats or molecular biology research. 1.0 × 10,000 sporozoites per 0.1 mL were inoculated into the allantoic cavity of ten-day-old chicken embryos. The complete life-cycle of E. tenella was accomplished in eight-nine days at 37 °C and 70% humidity. The addition of 100 U insulin to the embryos could remarkably improve the output of oocysts. The development of the parasite within the embryos was systematically observed, allowing guidelines to be set regarding the appropriate times at which different developmental stages of the parasite may be sampled.

Development of indirect ELISAs for differential serodiagnosis of classical and highly pathogenic porcine reproductive and respiratory syndrome virus

The objective of this study was to develop two indirect enzyme-linked immunosorbent assays (iELISAs) for detection of serum antibodies against classical vaccine strain of porcine reproductive and respiratory syndrome virus (PRRSV) and highly pathogenic PRRSV (HP-PRRSV). To detect the common antibodies against classical and HP-PRRSV, the coating antigen used in the iELISA (designated iELISA-180) was the antigen of Nsp2-180, the 180aa at amino terminal of Nsp2. To detect the different antibodies against classical and HP-PRRSV, the coating antigen in the second iELISA (designated iELISA-D29) was Nsp2-D29, the deleted 29aa in Nsp2 of HP-PRRSV. The antigen concentration and serum dilutions were optimized using a draughtboard titration. The cut-off values of 0.361 at OD(450nm) for the iELISA-180 and 0.27 at OD(450nm) for the iELISA-D29 were determined by testing a panel of 120 classical PRRSV positive and 198 PRRSV negative pig serum samples, which generated the specificity of 97.1% and 96.7%, the sensitivity of 96.9% and 96.3% for iELISA-180 and iELISA-D29, respectively. The agreements between the Western blot and iELISA-180 and iELISA-D29 were 98%, 96.7%, respectively. The developed iELISAs can be used to differentiate serologically HP-PRRSV from the vaccinated or classical PRRSV in clinical serum samples.

Mitochondrial bioenergetic deficits in the hippocampi of rats with chronic ischemia-induced vascular dementia

Vascular dementia (VD), defined as a loss of memory and cognitive function resulting from vascular lesions in the brain, is the second-most-common cause of dementia in the elderly, after Alzheimer's disease. In recent years, research has focused on the pathogenesis of VD, and mitochondrial bioenergetic deficits have been suggested to contribute to VD onset. To further investigate the role of mitochondria in VD, we used a rat model of VD, which involved permanent bilateral occlusion of the common carotid arteries (with a 1-week interval between artery occlusion to avoid an abrupt reduction in cerebral blood flow) leading to chronic cerebral hypoperfusion. Prior to occlusion, male Wistar rats underwent 7 days of Morris water maze training. Only animals that could swim and passed the Morris water maze test were chosen for the study. After 5 days of Morris water maze training, mitochondria from the hippocampi of rats, which were randomly selected from animals that could complete the Morris water maze test, were isolated for functional assessment. Mitochondria isolated from the hippocampi of rats from the ischemia group had decreased pyruvate dehydrogenase protein levels, and increased oxidative stress, as manifested by increased hydrogen peroxide production. The ischemia group mitochondria also exhibited decreased respiration coupled to decreased expression and activity of the electron transport chain complex IV (cytochrome c oxidase). These results indicate that the mitochondrial oxidative metabolism is inhibited in the hippocampi of rats following chronic ischemia-induced VD. As the mitochondrial oxidative metabolism deficits, namely mitochondrial bioenergetic deficits directly affect the functions of neurons, it may contribute to VD onset.

Development of the osseous and cartilaginous acetabular index in normal children and those with developmental dysplasia of the hip

The purpose of this study was to investigate the development of the osseous acetabular index (OAI) and cartilaginous acetabular index (CAI) using MRI. The OAI and CAI were measured on the coronal MR images of the hip in 81 children with developmental dysplasia of the hip (DDH), with a mean age of 19.6 months (3 to 70), and 241 normal control children with a mean age of 5.1 years (1 month to 12.5 years). Additionally the developmental patterns of the OAI and CAI in normal children were determined by age-based cross-sectional analysis.

Unlike the OAI, the normal CAI decreased rapidly from a mean of 10.17° (sd 1.60) to a mean of 8.25° (sd 1.90) within the first two years of life, and then remained constant at a mean of 8.04° (sd 1.65) until adolescence. Although no difference in OAI was found between the uninvolved hips in children with unilateral DDH and normal hips (p = 0.639), the CAI was significantly different between them both (p < 0.001). The normal CAI has fully formed at birth, and is maintained constantly throughout childhood. The CAI in the unaffected hips in children with unilateral DDH is also mildly dysplastic.

Evidence for the direct two-photon transition from ψ(3686) to J/ψ

The two-photon transition ψ(3686)→γγJ/ψ is studied in a sample of 1.06×10(8) ψ(3686) decays collected by the BESIII detector. The branching fraction is measured to be (3.1±0.6(stat)(-1.0)(+0.8)(syst))×10(-4) using J/ψ→e(+)e(-) and J/ψ→μ(+)μ(-) decays, and its upper limit is estimated to be 4.5×10(-4) at the 90% confidence level. This work represents the first measurement of a two-photon transition among charmonium states. The orientation of the ψ(3686) decay plane and the J/ψ polarization in this decay are also studied. In addition, the product branching fractions of sequential E1 transitions ψ(3686)→γχ(cJ) and χ(cJ)→γJ/ψ(J=0,1,2) are reported.

HIF-1α downregulates miR-17/20a directly targeting p21 and STAT3: a role in myeloid leukemic cell differentiation

Hypoxia-inducible factor 1 (HIF-1) is a crucial transcription factor for the cellular adaptive response to hypoxia, which contributes to multiple events in cancer biology. MicroRNAs (miRNAs) are involved in almost all cellular activities such as differentiation, proliferation, and apoptosis. In this work, we use miRNA microarrays to profile miRNA expression in acute myeloid leukemia (AML) cells with inducible HIF-1α expression, and identify 19 differentially expressed miRNAs. Our study shows that HIF-1α represses the expression of miR-17 and miR-20a by downregulating c-Myc expression. These two miRNAs alleviate hypoxia and HIF-1α-induced differentiation of AML cells. More intriguingly, miR-17 and miR-20a directly inhibit the p21 and STAT3 (signal transducer and activator of transcription 3) expression, both of which can reverse miR-17/miR-20a-mediated abrogation of HIF-1α-induced differentiation. Moreover, we show in vivo that miR-20a contributes to HIF-1α-induced differentiation of leukemic cells. Taken together, our results suggest that HIF-1α regulates the miRNA network to interfere with AML cell differentiation, representing a novel molecular mechanism for HIF-1-mediated anti-leukemic action.

Genomic and transcriptomic alterations following hybridisation and genome doubling in trigenomic allohexaploid Brassica carinata × Brassica rapa

Allopolyploidisation is a prominent evolutionary force that involves two major events: interspecific hybridisation and genome doubling. Both events have important functional consequences in shaping the genomic architecture of the neo-allopolyploids. The respective effects of hybridisation and genome doubling upon genomic and transcriptomic changes in Brassica allopolyploids are unresolved. In this study, amplified fragment length polymorphism (AFLP), methylation-sensitive amplification polymorphism (MSAP) and cDNA-AFLP approaches were used to track genetic, epigenetic and transcriptional changes in both allohexaploid Brassica (ArArBcBcCcCc genome) and triploid hybrids (ArBcCc genome). Results from these groups were compared with each other and also to their parents Brassica carinata (BBCC genome) and Brassica rapa (AA genome). Rapid and dramatic genetic, DNA methylation and gene expression changes were detected in the triploid hybrids. During the shift from triploidy to allohexaploidy, some of the hybridisation-induced alterations underwent reversion. Additionally, novel genetic, epigenetic and transcriptional alterations were also detected. The proportions of A-genome-specific DNA methylation and gene expression alterations were significantly greater than those of BC-genome-specific alterations in the triploid hybrids. However, the two parental genomes were equally affected during the ploidy shift. Hemi-CCG methylation changes induced by hybridisation were recovered after genome doubling. Full-CG methylation changes were a more general process initiated in the hybrid and continued after genome doubling. These results indicate that genome doubling could ameliorate genomic and transcriptomic alterations induced by hybridisation and instigate additional alterations in trigenomic Brassica allohexaploids. Moreover, genome doubling also modified hybridisation-induced progenitor genome-biased alterations and epigenetic alteration characteristics.

Gankyrin promotes breast cancer cell metastasis by regulating Rac1 activity

Tumor metastasis is responsible for most cancer patients' deaths. Understanding the mechanism of metastasis is crucial for improving the cure rate for cancer. Here, we report that Gankyrin, a chaperone of ubiquitin-proteasome, has an essential role in breast cancer metastasis. We find that Gankyrin is highly overexpressed in human breast cancers and the expression correlates strongly with lymph node metastasis. Knocking down Gankyrin expression in highly metastatic human breast cancer cells significantly decreases cancer cell migration and invasion. Furthermore, we demonstrate that depletion of Gankyrin inhibits intrinsic Rac1 activity and induces large focal adhesions. Overexpression of Gankyrin accelerates focal adhesion turnover and increases cell migration. Notably, reduction of Gankyrin expression in mouse mammary tumor cell significantly decreases tumor metastasis to lung in animal models. Therefore, our findings suggest that Gankyrin is crucial for breast cancer metastasis and highlight the potential of Gankyrin as a therapeutic target for tumor metastasis.

First observation of the M1 transition ψ(3686)→γη(c)(2S)

Using a sample of 106×10(6) ψ(3686) events collected with the BESIII detector at the BEPCII storage ring, we have made the first measurement of the M1 transition between the radially excited charmonium S-wave spin-triplet and the radially excited S-wave spin-singlet states: ψ(3686)→γη(c)(2S). Analyses of the processes ψ(3686)→γη(c)(2S) with η(c)(2S)→K(S)(0)K(±)π(∓) and K(+)K(-)π(0) give an η(c)(2S) signal with a statistical significance of greater than 10 standard deviations under a wide range of assumptions about the signal and background properties. The data are used to obtain measurements of the η(c)(2S) mass (M(η(c)(2S))=3637.6±2.9(stat)±1.6(syst) MeV/c(2)), width (Γ(η(c)(2S))=16.9±6.4(stat)±4.8(syst) MeV), and the product branching-fraction (B(ψ(3686)→γη(c)(2S))×B(η(c)(2S)→KKπ)=(1.30±0.20(stat)±0.30(syst))×10(-5)). Combining our result with a BABAR measurement of B(η(c)(2S)→KKπ), we find the branching fraction of the M1 transition to be B(ψ(3686)→γη(c)(2S))=(6.8±1.1(stat)±4.5(syst))×10(-4).

Measurements of the mass and width of the η(c) using the decay ψ(3686)→γη(c)

The mass and width of the lowest-lying S-wave spin singlet charmonium state, the η(c), are measured using a data sample of 1.06×10(8) ψ(3686) decays collected with the BESIII detector at the BEPCII storage ring. We use a model that incorporates full interference between the signal reaction, ψ(3686)→γη(c), and a nonresonant radiative background to describe the line shape of the η(c) successfully. We measure the η(c) mass to be 2984.3±0.6±0.6 MeV/c(2) and the total width to be 32.0±1.2±1.0 MeV, where the first errors are statistical and the second are systematic.