The emerging role of Toll-like receptor 4 in myocardial inflammation

Toll-like receptors (TLRs) are a family of pattern recognition receptors involved in cardiovascular diseases. Notably, numerous studies have demonstrated that TLR4 activates the expression of several of pro-inflammatory cytokine genes that play pivotal roles in myocardial inflammation, particularly myocarditis, myocardial infarction, ischemia-reperfusion injury, and heart failure. In addition, TLR4 is an emerging target for anti-inflammatory therapies. Given the significance of TLR4, it would be useful to summarize the current literature on the molecular mechanisms and roles of TLR4 in myocardial inflammation. Thus, in this review, we first introduce the basic knowledge of the TLR4 gene and describe the activation and signaling pathways of TLR4 in myocardial inflammation. Moreover, we highlight the recent progress of research on the involvement of TLR4 in myocardial inflammation. The information reviewed here may be useful to further experimental research and to increase the potential of TLR4 as a therapeutic target.

Functional porous composites by blending with solution-processable molecular pores

We present a simple method for rendering non-porous materials porous by solution co-processing with organic cage molecules. This method can be used both for small functional molecules and for polymers, thus creating porous composites by molecular blending, rather than the more traditional approach of supporting functional molecules on pre-frabricated porous supports.

[The application of extended high frequency audiometry in detecting the early hearing loss for thalassemia]

Objective:To preliminarily explore the clinical significance of extended high frequency audiometry in evaluating the early hearing loss for thalassemia.Method:Pure tone audiometry(PTA) included conventional pure tone audiometry and extended high frequency audiometry were obtained on the pre and post-treatment day in 60(117 ears) patients from September in 2013 to October in 2014. Result:The averages of conventional pure tone audiometry for 117 cases were（15.72±11.62）dBHL on the pre-treatment day and（15.40±12.24）dBHL on the post-treatment day. There were no significant differences in PTA(P >0.05). But the hearing without detection rate was higher than before especially at 18 and 19 kHz. The differences of the hearing without detection rate between the pre-treatment and the post-treatment day were statistically significant(P <0.05).Conclusion:The extended high frequency may be more sensitive in evaluating the early hearing loss for thalassemia.

The Effectiveness of hCG and LHRH in Boys with Cryptorchidism: A Meta-Analysis of Randomized Controlled Trials

To systematically review the efficacy of hCG and LHRH on testicular descent in boys with cryptorchidism, comprehensive search was performed to identify randomized controlled trials (RCTs) in PubMed, EMBASE, the Cochrane Library, Wanfang Database, and China National Knowledge Infrastructure (CNKI) up to March 2014. Outcomes included testicular complete descent rate (TCDR) and cure rate of patients. Study quality was evaluated using the Jadad scale. Meta-analysis was performed using Review Manager software. Finally, 13 studies were included. hCG and LHRH increased TCDR comparing with control group. The success rate of hCG and LHRH was 24 and 19%, respectively. Further, hCG and LHRH had significant effect on bilateral cryptorchidism, but not on unilateral cryptorchidism. All side effects were transitory and not severe, but if they have long-term harms were not clear. hCG and LHRH can effectively increase TCDR and there was no significant difference between them. However, the hormones cannot be recommended for everyone because of their low success rates and potential long-term harms. Further studies are needed to determine the efficacy of hormonal treatment for subtypes of cryptorchidism.

miR-155 downregulates ErbB2 and suppresses ErbB2-induced malignant transformation of breast epithelial cells

ErbB2 is a vital breast cancer gene and its overexpression has a decisive role in breast tumor initiation and malignant progression. However, the molecular mechanisms that underlie ErbB2 dysregulation in breast cancer cells remain incompletely understood. In this study, we found that ErbB2 expression is inversely correlated with the level of miR-155, a well-documented oncogenic miRNA, in ErbB2-positive breast tumors. We further determined that miR-155 potently suppresses ErbB2 in breast cancer cells. Mechanistically, miR-155 acts to downregulate ErbB2 via two distinct mechanisms. First, miR-155 represses ErbB2 transcription by targeting HDAC2, a transcriptional activator of ErbB2. Second, miR-155 directly targets ErbB2 via a regulatory element in its coding region. Intriguingly, miR-155 is upregulated by trastuzumab and in turn leads to a reduction of ErbB2 expression in trastuzumab-treated ErbB2-positive breast cancer cells. Functional studies showed that miR-155 inhibits ErbB2-induced malignant transformation of human breast epithelial cells. Thus, our findings reveal an intriguing miR-155-ErbB2 context in regulating the malignant transformation of breast epithelial cells, and thereby indicate a novel mode of action for miR-155 in ErbB2-positive breast cancer.

Interleukin-35 upregulates OPG and inhibits RANKL in mice with collagen-induced arthritis and fibroblast-like synoviocytes

IL-35 is a novel anti-inflammatory cytokine, but the exact role of IL-35 in the progression of RA remains unclear, especially associated with osteoporosis and bone erosion. The present research has not been reported. Our purpose is to study how IL-35 affects RA bone destruction.

INTRODUCTION

This study investigated the effect of interleukin-35 (IL-35) on OPG and RANKL expression in collagen-induced arthritis (CIA) in rats and in cultured fibroblast-like synoviocytes (FLS).

METHODS

Thirty DBA/1J mice were randomly assigned to three groups (n = 10 per group): the control group, the CIA group, and the CIA + IL-35 group. Collagen-induced arthritis was induced by immunization with collagen. IL-35 was intraperitoneally injected daily for 10 days, starting from the 24(th) day after immunization. FLS cells were isolated and cultured from CIA. The expression of IL-17, RANKL, and OPG was determined by RT-PCR and Western blot. Each experiment was repeated three times.

RESULTS

CIA mice exhibited arthritis symptoms on day 24, followed by a rapid progression of arthritis. The expression of IL-17 and RANKL was increased and the expression of OPG was decreased in CIA mice compared with control mice. IL-35 treatment inhibited the development of arthritis in CIA mice, accompanied by a decrease in the expression of IL-17 and RANKL and an increase in the expression of OPG. Furthermore, IL-35 dose-dependently inhibited the expression of RANKL and increased the expression of OPG in cultured FLS cells.

CONCLUSION

IL-35 inhibits RANKL expression and increases OPG expression in CIA mice. IL-35 may be used for treating rheumatoid arthritis.

Risk factors for pulmonary hypertension in patients receiving maintenance peritoneal dialysis

We investigated the risk factors for pulmonary hypertension (PH) in patients receiving maintenance peritoneal dialysis (MPD). A group of 180 end-stage renal disease patients (124 men and 56 women; mean age: 56.43±8.36) were enrolled in our study, which was conducted between January 2009 and June 2014. All of the patients received MPD treatment in the Dialysis Center of the Second Affiliated Hospital of Soochow University. Clinical data, laboratory indices, and echocardiographic data from these patients were collected, and follow-ups were scheduled bi-monthly. The incidence and relevant risk factors of PH were analyzed. The differences in measurement data were compared by t-test and enumeration data were compared with the χ2 test. Among the 180 patients receiving MPD, 60 were diagnosed with PH. The remaining 120 were regarded as the non-PH group. Significant differences were observed in the clinical data, laboratory indices, and echocardiographic data between the PH and non-PH patients (all P<0.05). Furthermore, hypertensive nephropathy patients on MPD showed a significantly higher incidence of PH compared with non-hypertensive nephropathy patients (P<0.05). Logistic regression analysis showed that the proportion of internal arteriovenous fistula, C-reactive protein levels, and ejection fraction were the highest risk factors for PH in patients receiving MPD. Our study shows that there is a high incidence of PH in patients receiving MPD and hypertensive nephropathy patients have an increased susceptibility to PH.

Microengineering Laser Plasma Interactions at Relativistic Intensities

We report on the first successful proof-of-principle experiment to manipulate laser-matter interactions on microscales using highly ordered Si microwire arrays. The interaction of a high-contrast short-pulse laser with a flat target via periodic Si microwires yields a substantial enhancement in both the total and cutoff energies of the produced electron beam. The self-generated electric and magnetic fields behave as an electromagnetic lens that confines and guides electrons between the microwires as they acquire relativistic energies via direct laser acceleration.

Dosimetric and clinical toxicity comparison of critical organ preservation with three-dimensional conformal radiotherapy, intensity-modulated radiotherapy, and RapidArc for the treatment of locally advanced cancer of the pancreatic head

PURPOSE

We compared dosimetry and clinical toxicity for 3-dimensional conformal radiotherapy (3D-crt), intensity-modulated radiotherapy (imrt), and RapidArc (Varian Medical Systems, Palo Alto, CA, U.S.A.) in locally advanced pancreatic cancer (lapcc). We hypothesized that the technique with better sparing of organs at risk (oars) and better target dose distributions could lead to decreased clinical toxicity.

METHODS

The study analyzed 280 patients with lapcc who had undergone radiotherapy. The dosimetry comparison was performed using 20 of those patients. Dose-volume histograms for the target volume and the oars were compared. The clinical toxicity comparison used the 280 patients who received radiation with 3D-crt, imrt, or RapidArc.

RESULTS

Compared with 3D-crt, RapidArc and imrt both achieved a better conformal index, homogeneity index, V95%, and V110%. Compared with 3D-crt or imrt, RapidArc reduced the V10, V20, and mean dose to duodenum, the V20 of the right kidney, and the liver mean dose. Compared with 3D-crt, RapidArc reduced the V35, and V45 of duodenum, the mean dose to small bowel, and the V15 of right kidney. The incidences of grades 3 and 4 diarrhea (p = 0.037) and anorexia (p = 0.042) were lower with RapidArc than with 3D-crt, and the incidences of grades 3 and 4 diarrhea (p = 0.027) were lower with RapidArc than with imrt.

CONCLUSIONS

Compared with 3D-crt or imrt, RapidArc showed better sparing of oars, especially duodenum, small bowel, and right kidney. Also, fewer acute grades 3 and 4 gastrointestinal toxicities were seen with RapidArc than with 3D-crt or imrt. A technique with better sparing of oars and better target dose distributions could result in decreased clinical toxicities during radiation treatment for lapcc.

Abstract P5-05-05: Inhibition of enhanced glucose uptake and glycolysis by KU-55933 as a novel strategy against aggressive breast cancer

The ability of cancer cells to produce large amounts of lactate through aerobic glycosis (Warburg effect) is coupled to high rates of glucose uptake. Enhanced glucose uptake and glycolysis are closely correlated to increased breast tumor aggressiveness and poor prognosis. However, despite the importance of glucose uptake in supplying energy and preventing apoptosis of cancer cells, the majority of current efforts in searching for therapeutic agents targeting glucose metabolism have been aimed at modulating activities of different metabolic enzymes that are involved in glycolysis. Very limited studies have been done in developing novel therapeutic agents against glucose uptake in breast cancer cells.

Ataxia-telangiectasia (A-T) is a monogenic, autosomal recessive disorder characterized by cerebellar ataxia and oculocutaneous telangiectasias. The gene mutated in this disease, ATM (A-T, mutated), encodes a 370-kDa protein kinase. Although ATM is traditionally considered to be a nuclear protein that functions as a signal transducer in the cellular response to DNA damage, it is now known that ATM is also present in the cytoplasm and has important cytoplasmic functions. We previously discovered that ATM activates Akt, a main regulator of glucose uptake, by stimulating its phosphorylation at Ser473 following insulin treatment. We also found that ATM participates in insulin-mediated glucose uptake in muscle cells, and KU-55933, a specific inhibitor of ATM, strongly inhibits this process.

Recently, we found that KU-55933 inhibits cell proliferation by inducing apoptosis in MDA-MB-231, a triple-negative breast cancer cell line. We have also found that KU-55933 inhibits migration of MDA-MB-231 by a cell invasion assay. Furthermore, we found that these cancer cells exhibit enhanced glucose uptake in response to insulin and the addition of KU-55933 leads to a dramatic reduction of insulin-mediated glucose uptake in these cells. To further test whether KU-55933's ability to induce apoptosis is linked to its inhibition of glucose uptake, we performed a cell death ELISA assay in MDA-MB-231 cells treated with KU-55933 and different concentrations of glucose. Our results show that KU-55933 induces apoptosis of MDA-MB-231 cells, resulting in a similar degree of cell death as glucose starvation, while cells treated with glucose in conjunction with KU-55933 have decreased apoptosis. Moreover, we performed a cell migration assay and found that KU-55933 strongly inhibits the migration of MDA-MB-231 cells (similar to that caused by glucose starvation), which is almost fully rescued by the extra glucose supplemented in the cell culture medium. We have also established a positional isotope labeling-based targeted metabolomics method that can directly measure the conversion from glucose to lactate through glycolysis in cancer cells. Our results show strong production of lactate from glucose in MDA-MB-231 cells even under normal aerobic growth conditions, and KU-55933 strongly inhibits this process. Our findings may lead to the development of KU-55933 and its analogs as a new generation of therapeutic agents against aggressive breast cancer.

Citation Format: Yang D-Q, Harris B, Jiang S, Li Y, Freund D, Hegeman A, Cleary M. Inhibition of enhanced glucose uptake and glycolysis by KU-55933 as a novel strategy against aggressive breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-05-05.

Intensity of delivery room resuscitation and neonatal outcomes in infants born at 33 to 36 weeks' gestation

OBJECTIVE

Examine the relationship between delivery room resuscitation intensity and mortality, morbidities and resource use in late preterm infants.

STUDY DESIGN

Retrospective cohort study of inborn infants born at 33 to 36 weeks' gestation and admitted to Canadian neonatal intensive care units during 2010 to 2013. The 13 619 infants were grouped according to delivery room resuscitation intensity: no or minimal resuscitation (64.5%); continuous positive airway pressure (10.2%); bag-mask ventilation (21.7%); endotracheal intubation (3.1%); and cardiopulmonary resuscitation (CPR) (0.6%).

RESULTS

Overall mortality, early mortality, respiratory distress, pneumothorax, late-onset sepsis and resource use increased with higher intensity resuscitation. Compared with no or minimal resuscitation, intubation and CPR were associated with increased odds of mortality (adjusted odds ratio (95% confidence interval): 50 (20 to 125) and 180 (63 to 518), respectively).

CONCLUSIONS

Intubation or higher intensity delivery room resuscitation is associated with increased mortality, morbidities and resource use in late preterm infants. Extra intensive care is required for such infants, especially during the first week of life.

Mesoporous NiCo2O4 nanospheres with a high specific surface area as electrode materials for high-performance supercapacitors

Ternary nickel cobaltite has attracted more and more attention as a promising electrode material for high performance supercapacitors (SCs) due to its high theoretical capacity, unique crystal structure and excellent electronic conductivity.

Schwannomas of female genitalia from a gynaecologist's perspective: report of two cases and review of the literature

BACKGROUND

Pelvic schwannomas are extremely rare. However, when located in the pelvic cavity, schwannomas are often encountered by a gynaecologist, not a general surgeon, and are misdiagnosed as gynaecologic masses.

CASE REPORT

Here, the authors present two cases of pelvic schwannomas that were preoperatively misdiagnosed as broad ligament fibroid. One schwannoma occurred completely in the left broad ligament and was resected by laparoscopy without any complications. The other lesion was located in the retroperitoneum and had densely adhered to the surrounding tissues; this lesion was excised by laparotomy with considerable blood loss.

CONCLUSIONS

Schwannomas of female genitalia are very scarce and difficulty to diagnose preoperatively. Literature review revealed 63 schwannomas arising from the female genital tract in total, 73.02% (46 cases) were located in the lower genital tract, and 26.98% (17 cases) were located in upper genital tract. The treatment modality is unique depending on the location of the tumor. Complete excision is benefical for diagnosis and treatment. The procedure can be performed safely under laparoscopy.

Characterization of the nuclear localization signals of duck circovirus replication proteins

Duck circovirus (DuCV) possess a circular, single-stranded DNA genome that requires the replication protein (Rep) for its replication. Based on the viral genotype, there are two categories of Rep proteins: Rep1 and Rep2. To characterize the nuclear localization signals (NLSs) conferring the nuclear localization of the Rep proteins, defined coding regions of the rep gene of two genotypes of DuCV were cloned and co-expressed with the red fluorescent protein DsRed2. The results showed that deleting the putative N-terminal NLS located at amino acid residues 10-37 of Rep1 and Rep2 abrogated nuclear translocation, while deleting the putative C-terminal NLS located at residues 244-274 of Rep1 did not significantly alter its subcellular localization, confirming that only the NLS located at residues 10-37 in the N-termini of the Rep proteins had nuclear targeting activity.

Putative suppressing effect of IgG Fc-conjugated haemagglutinin (HA) stalk of influenza virus H7N9 on the neutralizing immunogenicity of Fc-conjugated HA head: implication for rational design of HA-based influenza vaccines

The emergence of influenza A H7N9 in infection has posed a great threat to public health globally. Poor immunogenicity of H7N9 haemagglutinin (HA) is a major obstacle to the development of an effective H7N9 vaccine. Here, we found that the vaccine containing the H7HA head conjugated with IgG Fc (Hd-Fc) induced strong neutralizing antibody responses and protection against H7N9 infection, whilst the Fc-conjugated H7HA stalk (St-Fc)-based vaccine could not induce neutralizing antibodies, although the St-Fc-immunized mice were partially protected. The vaccines containing the full-length extracellular domain of HA conjugated with Fc and the mixture of Hd-Fc plus St-Fc induced significantly lower neutralizing antibody and haemagglutination inhibition titres than the Hd-Fc-based vaccine. These results suggest that the St-Fc may have inhibitory effects on the neutralizing immunogenicity of Hd-Fc. Therefore, the neutralizing domain(s), such as the receptor-binding domain, in the HA head should be kept and the non-neutralizing domain(s) in the HA stalk with the ability to potentially suppress the neutralizing immunogenicity of HA head should be removed from Fc-conjugated HA-based influenza vaccines to increase the neutralizing antibody response.

Preparation and identification of an antiserum against recombinant UL31 protein of pseudorabies virus

Pseudorabies virus (PRV) early protein UL31 is a homologue of herpes simplex virus 1 (HSV-1) UL31, which is a multifunctional protein important for HSV-1 infection. However, the precise roles of PRV UL31 in virus life cycle are still poorly understood. A relatively crucial tool for uncovering the function of UL31 is an antiserum that specifically detects UL31 in the PRV-infected cells. For this purpose, a recombinant UL31 protein consisting of N-terminal 27 aa of UL31 fused to EYFP and His-tag was expressed, purified and used for the preparation of antiserum in BALB/c mice. Our results show that Western blot analysis and immunofluorescence assay showed that this antiserum could specifically detect the purified recombinant UL31 as well as full-length UL31 in the PRV infected cells. These results demonstrate that the prepared antiserum could serve as a valuable tool for further studies of UL31 functions in PRV infection.

The efficacy of propofol on emergence agitation--a meta-analysis of randomized controlled trials

BACKGROUND

Emergence agitation (EA) is a common, post-anesthetic complication in pediatric patients following sevoflurane and desflurane anesthesia. The aim of this meta-analysis was to assess the effects of an adjunctive dose of propofol to reduce the incidence of EA in pediatric patients.

METHODS

A comprehensive literature review was conducted to identify clinical trials focusing on the effects of propofol on EA in children under sevoflurane and desflurane anesthesia. The MEDLINE, EMBASE, Wiley Online Library, Web of Science, China National Knowledge Internet databases, and other sources were searched. The data were combined to calculate the pooled relative ratio (RR) or mean difference (MD), and relevant 95% confidence interval (CI). Heterogeneity and potential publication bias were assessed. The required information size was calculated and a Lan-DeMets sequential monitoring boundary was constructed to improve the precision of our findings.

RESULTS

Data from 11 studies showed that an adjunctive dose of propofol conveyed a preventive effect on EA, as compared with placebo (RR = 0.56; 95% CI = 0.43-0.74; P < 0.0001). There was no significant difference in the length of stay in the post-anesthesia care unit between groups (MD = 0.25 min; 95% CI = -2.81 to 2.31; P = 0.85). The required information size was 2297 patients and the Lan-DeMets sequential monitoring boundary was crossed. However, most of the included studies had a high risk of bias and non-ignorable inter-study and clinical heterogeneity.

CONCLUSION

Future studies on the benefits of adjunct propofol in reducing the incidence of EA are required.

In vivo and in vitro inhibitory action of 17β-estradiol and environmental estrogen 4-nonylphenol on gonad-inhibiting hormone (GIH) expression in the eyestalks of Litopenaeus vannamei

The gonad-inhibiting hormone (GIH) belongs to a neuropeptide family synthesized and released in an X-organ sinus gland complex of crustacean eyestalks. GIH inhibits crustacean ovarian maturation by suppressing vitellogenin (Vtg) synthesis, whereas estrogen is responsible for the stimulation of vitellogenesis (not established). In this study, the effects of 17β-estradiol (E2, 10(-6) M), estrogen receptor antagonist tamoxifen (TAM, 10(-6), 10(-7), and 10(-8) M), and the environmental estrogen nonylphenol (NP, 1 μg/L and 100 μg/L) on LvGIH expression in the eyestalks of shrimp were determined by quantitative real-time PCR. Results showed that LvGIH expression decreased significantly during the L. vannamei ovarian maturation cycle. E2 and NP significantly reduced LvGIH transcripts in vivo, but TAM neutralized the inhibitory action of E2 in a dose-dependent manner (P < 0.05). In addition, the LvGIH expression levels decreased significantly in a time-dependent manner (P < 0.05) when ovary fragments were cultured in vitro with E2. The results of this study suggested that estrogen regulates GIH expression in L. vannamei eyestalks. E2 promoted ovarian development not only by directly upregulating vitellogenesis in the hepatopancreas, but it was also capable of downregulating LvGIH expression, which indirectly resulted in the stimulation of L. vannamei vitellogenesis.

Genome-wide differential expression of synaptic long noncoding RNAs in autism spectrum disorder

A genome-wide differential expression of long noncoding RNAs (lncRNAs) was identified in blood specimens of autism spectrum disorder (ASD). A total of 3929 lncRNAs were found to be differentially expressed in ASD peripheral leukocytes, including 2407 that were upregulated and 1522 that were downregulated. Simultaneously, 2591 messenger RNAs (mRNAs), including 1789 upregulated and 821 downregulated, were also identified in ASD leukocytes. Functional pathway analysis of these lncRNAs revealed neurological pathways of the synaptic vesicle cycling, long-term depression and long-term potentiation to be primarily involved. Thirteen synaptic lncRNAs, including nine upregulated and four downregulated, and 19 synaptic mRNAs, including 12 upregulated and seven downregulated, were identified as being differentially expressed in ASD. Our identification of differential expression of synaptic lncRNAs and mRNAs suggested that synaptic vesicle transportation and cycling are important for the delivery of synaptosomal protein(s) between presynaptic and postsynaptic membranes in ASD. Finding of 19 lncRNAs, which are the antisense, bi-directional and intergenic, of HOX genes may lead us to investigate the role of HOX genes involved in the development of ASD. Discovery of the lncRNAs of SHANK2-AS and BDNF-AS, the natural antisense of genes SHANK2 and BDNF, respectively, indicates that in addition to gene mutations, deregulation of lncRNAs on ASD-causing gene loci presents a new approach for exploring possible epigenetic mechanisms underlying ASD. Our study also opened a new avenue for exploring the use of lncRNA(s) as biomarker(s) for the early detection of ASD.

Link of obesity and gastrointestinal cancer: crossroad of inflammation and oxidative stress

Obesity incidence has reached pandemic levels, and is accompanied by high incidence and poor prognosis of various types of cancers including gastrointestinal ones. Underlying mechanisms include elevated levels of insulin, IGF-I, and altered adipokine concentration, mainly towards leptin and adiponectin levels. However, it is not yet thoroughly understood. It is now widely known that obesity is associated with chronic low-grade inflammation, characteristic of altered immune cell infiltration in adipose tissue, and changed inflammatory cytokines and chemokines: tumor necrosis factor alpha (TNF-a), IL-6, and the chemoattractant monocyte chemoattractant protein 1 (MCP-1) and others, all together eventually promoting caner pathogenesis. Moreover, accumulating reports have shown that excess adipose tissue in obese individuals resulted in elevated levels of systematic oxidative stress, another way of promoting cancer development and progression. In general, altered immunological milieu and oxidative stress in obesity are important determinants for tumorigenesis.

Impaired neurogenesis by HIV-1-Gp120 is rescued by genetic deletion of fatty acid amide hydrolase enzyme

Background and Purpose

The HIV-envelope glycoprotein Gp120 is involved in neuronal injury and is associated with neuro-AIDS pathogenesis in the brain. Endocannabinoids are important lipid ligands in the CNS regulating neural functions, and their degeneration is controlled by hydrolysing enzymes such as the fatty acid amide hydrolase (FAAH). Here, we examined whether in vivo genetic deletion of Faah gene prevents HIV-1 Gp120-mediated effects on neurogenesis.

Experimental Approach

We generated new GFAP/Gp120 transgenic (Tg) mice that have genetic deletion of Faah gene by mating glial fribillary acidic protein (GFAP)/Gp120 Tg mice with Faah−/− mice. Neurogenesis and cell death were assessed by immunocytochemical analysis.

Key Results

Endocannabinoid levels in the brain of the double GFAP/Gp120//Faah−/− mice were similar to those observed in Faah−/− mice. However, unlike the impaired neurogenesis observed in GFAP/Gp120 Tg mice and Faah−/− mice, these GFAP/Gp120//Faah-/ mice showed significantly improved neurogenesis in the hippocampus, indicated by a significant increase in neuroblasts and neuronal cells, an increase in BrdU⁺ cells and doublecortin positive cells (DCX⁺), and an increase in the number of PCNA. Furthermore, a significant decrease in astrogliosis and gliogenesis was observed in GFAP/Gp120//Faah−/−mice and neurogenesis was stimulated by neural progenitor cells (NPCs) and/or the newly formed NPC niches characterized by increased COX-2 expression and elevated levels of PGE₂.

Conclusions and Implications

In vivo genetic ablation of Faah, resulted in enhanced neurogenesis through modulation of the newly generated NPC niches in GFAP/Gp120//Faah−/− mice. This suggests a novel approach of using FAAH inhibitors to enhance neurogenesis in HIV-1 infected brain.

Capability of GaN based micro-light emitting diodes operated at an injection level of kA/cm²

Different size InGaN/GaN based micro-LEDs (μLEDs) are fabricated. An extremely high injection level above 16 kA/cm2 is achieved for 10 μm-diameter LED. The lateral current density and carrier distributions of the μLEDs are simulated by APSYS software. Streak camera time resolved photoluminescence (TRPL) results show clear evidence that the band-gap renormalization (BGR) effect is weakened by strain relaxation in smaller size μLEDs. BGR affects the relaxation of free carriers on the conduction band bottom in multiple quantum wells (MQWs), and then indirectly affects the recombination rate of carriers. An energy band model based on BGR effect is made to explain the high-injection-level phenomenon for μLEDs.