Role of growth hormone, glutamine and enteral nutrition in pediatric short bowel syndrome: a pilot follow-up study

OBJECTIVE

Aim of the study was to evaluate whether growth hormone (GH), glutamine (Gln), and enteral nutrition (EN) have a positive effect on intestinal adaptation in pediatric patients with short bowel syndrome (SBS).

METHOD

7 pediatric patients with SBS (small bowel remnant length: 60.57 ± 15.18 cm; mean ± SEM) were treated with GH (0.05 mg/kg/day), supplemental Gln (0.45 g/kg/day), plus EN for 3 weeks. After 3 weeks of treatment, GH was discontinued, and patients were maintained on Gln and EN or additionally received a high-carbohydrate-low-fat diet. Repeat treatment was given at regular intervals. Changes in weight and height increase, intestinal absorptive capacity and blood indices were evaluated.

RESULT

All patients completed the treatment. The intestinal absorptive capacity and plasma levels of proteins were significantly improved after treatment. There were no major adverse effects in any patient and no death occurred. Growth velocity was also well maintained on follow-up. 6 patients were weaned off PN and lived on HCLF diet supplement with EN, while the last patient required less volume of PN.

CONCLUSION

Multiple treatment approaches with GH, Gln, and EN at an early stage significantly improved intestinal adaptation in pediatric patients with SBS. Furthermore, the positive effect appeared to be sustained even after GH was discontinued.

Observation of two charged bottomoniumlike resonances in Υ(5S) decays

We report the observation of two narrow structures in the mass spectra of the π(±)Υ(nS) (n=1, 2, 3) and π(±)h(b)(mP) (m=1, 2) pairs that are produced in association with a single charged pion in Υ(5S) decays. The measured masses and widths of the two structures averaged over the five final states are M(1)=(10,607.2±2.0)  MeV/c2, Γ(1)=(18.4±2.4)  MeV, and M(2)=(10,652.2±1.5)  MeV/c2, Γ(2)=(11.5±2.2)  MeV. The results are obtained with a 121.4  fb(-1) data sample collected with the Belle detector in the vicinity of the Υ(5S) resonance at the KEKB asymmetric-energy e+ e- collider.

Differential response of normal human epidermal keratinocytes and HaCaT cells to hydrogen peroxide-induced oxidative stress

BACKGROUND

  Normal human epidermal keratinocytes (NHEKs) and HaCaT cells are the most common models used to study the effects of various factors on skin cells. These cell lines share some common characteristics, but little is known about their differences in handling hydrogen peroxide (H(2) O(2) )-induced oxidative stress.

AIM

To investigate the differential response of NHEKs and HaCaT cells to H(2) O(2) -induced oxidative stress.

METHODS

We examined differences in NHEKs and HaCaT cells after H(2) O(2) treatment, assessing changes in cell viability; levels of intracellular reactive oxygen species (ROS), superoxide dismutase (SOD) and caspase-3/7; percentage of cells arrested in G1 phase; number of senescence-associated β-galactosidase (SA-β-Gal)-positive cells and; expression of senescence-related protein Klotho.

RESULTS

The viability of NHEKs and HaCaT cells decreased in a concentration-dependent and time-dependent manner after exposure to H(2) O(2) . The inhibitory effect of 150 μmol/L H(2) O(2) on cell viability was greater in HaCaT cells than in NHEKs (P<0.05). Levels of ROS and caspase-3/7, and the percentage of cells arrested in G1 phase, were higher in HaCaT cells than in NHEKs, whereas intracellular SOD was higher in NHEKs than in HaCaT cells after exposure to 150 μmol/L H(2) O(2) (P < 0.05). SA-β-Gal positive cells increased significantly in NHEKs after treatment with H(2) O(2) (P < 0.05). Klotho was significantly downregulated in both NHEKs and HaCaT cells after H(2) O(2) treatment, but no SA-β-Gal-positive HaCaT cells were seen, even after treatment with H(2) O(2) .

CONCLUSIONS

Normal human epidermal keratinocytes are more resistant than HaCaT cells to H(2) O(2) -induced oxidative stress. HaCaT cells have senescence phenotypes, but do not express β-Gal.

Mallory-Denk bodies form when EZH2/H3K27me3 fails to methylate DNA in the nuclei of human and mice liver cells

EZH2/H3K27me3 and polycomb group complex (PcG) play a major role in regulating global gene expression including tumor suppressor genes. EZH2 is linked to cell cycle regulated EZH2 phosphorylation by CDK1, a mitotic kinase which increases in arrested mitosis compared to S phase. CDK1 phosphorylation of EZH2 accelerates the degradation of pEZH2. Phospho-EZH2 is subjected to ubiquitination. The half-like of pEZH2 is shorter when compared to total EZH2. In the present study, pEZH2 was found concentrated together with ubiquitin in the Mallory-Denk bodies (MDB) that were formed in hepatocytes in the livers of drug primed mice refed DDC and humans with alcoholic hepatitis or hepatocellular carcinoma. The cells that formed MDBs in the mice livers studied were associated with a growth advantage and a high proliferative index. However, the livers from patients with alcoholic hepatitis showed evidence of cell cycle arrest where PCNA, cyclin D1 and p27 positive nuclei were numerous but Ki-67 positive nuclei were scarce. It is concluded that MDB formation is linked to the cell cycle and global gene expression (i.e. loss of gene silencing) through its association with the regulation of the polycomb group PRC2/EZH2/H3K27me3 complex.

Mesenchymal stem cells: a double-edged sword in regulating immune responses

Mesenchymal stem cells (MSCs) have been employed successfully to treat various immune disorders in animal models and clinical settings. Our previous studies have shown that MSCs can become highly immunosuppressive upon stimulation by inflammatory cytokines, an effect exerted through the concerted action of chemokines and nitric oxide (NO). Here, we show that MSCs can also enhance immune responses. This immune-promoting effect occurred when proinflammatory cytokines were inadequate to elicit sufficient NO production. When inducible nitric oxide synthase (iNOS) production was inhibited or genetically ablated, MSCs strongly enhance T-cell proliferation in vitro and the delayed-type hypersensitivity response in vivo. Furthermore, iNOS^−/− MSCs significantly inhibited melanoma growth. It is likely that in the absence of NO, chemokines act to promote immune responses. Indeed, in CCR5^−/−CXCR3^−/− mice, the immune-promoting effect of iNOS^−/− MSCs is greatly diminished. Thus, NO acts as a switch in MSC-mediated immunomodulation. More importantly, the dual effect on immune reactions was also observed in human MSCs, in which indoleamine 2,3-dioxygenase (IDO) acts as a switch. This study provides novel information about the pathophysiological roles of MSCs.

MDM2 regulates MYCN mRNA stabilization and translation in human neuroblastoma cells

The MYCN gene has a critical role in determining the clinical behavior of neuroblastoma. Although it is known that genomic amplification occurs in high-risk subsets, it remains unclear how MYCN expression is regulated in the pathogenesis of neuroblastomas. Here, we report that MYCN expression was regulated by the oncoprotein MDM2 at the post-transcriptional level and was associated with neuroblastoma cell growth. Increasing MDM2 by ectopic overexpression in the cytoplasm enhanced both mRNA and protein expression of MYCN. Mechanistic studies found that the C-terminal RING domain of the MDM2 protein bound to the MYCN mRNA's AREs within the 3'UTR and increased MYCN 3'UTR-mediated mRNA stability and translation. Conversely, MDM2 silencing by specific siRNA rendered the MYCN mRNA unstable and reduced the abundance of the MYCN protein in MYCN-amplified neuroblastoma cell lines. Importantly, this MDM2 silencing resulted in a remarkable inhibition of neuroblastoma cell growth and induction of cell death through a p53-independent pathway. Our results indicate that MDM2 has a p53-independent role in the regulation of both MYCN mRNA stabilization and its translation, suggesting that MDM2-mediated MYCN expression is one mechanism associated with growth of MYCN-associated neuroblastoma and disease progression.

Modification of glycosylation reduces microvilli on rat liver epithelial cells

Effect of glycosylation modification on the shape of microvillus was investigated on rat liver epithelial cell line WB-F344. Since rat ER alpha-mannosidase has 89% identity to human 6A8 alpha-mannosidase, we used an antisense 6A8 cDNA fragment to inhibit expression in WB-F344 cells. Cells were transfected with antisense 6A8, the relevant sense fragment or the mock plasmid. Genomic PCR for neo(R) demonstrated integration of the transfected gene into host DNA. Enzymatic activity assay on p -nitro-phenyl-alpha-D-mannopyranoside showed suppression of ER alpha-mannosidase expression in the cells transfected with antisense 6A8. Concanavalin A binding to these cells was enhanced, indicating a modification in glycosylation. Number reduction and blunting of microvillus on these cells was observed. Transduction with the sense fragment or the mock had no effect. Cells with suppressed ER alpha-mannosidase expression grew slower in culture. Our results indicate an obvious effect of glycosylation modification on microvilli, which might be related with malfunctioning of cells.

Maternal and neonatal outcomes associated with gestational diabetes in women from culturally and linguistically diverse backgrounds in Western Australia

AIMS

To compare maternal and neonatal outcomes for Australian-born women with gestational diabetes mellitus with those of culturally and linguistically diverse and non-culturally and linguistically diverse foreign-born women with gestational diabetes.

METHODS

A total of 205,616 singleton births in Western Australia between 1998 and 2006 were examined using multivariate logistic regression. Risks of ten maternal and neonatal outcomes associated with gestational diabetes were compared for pregnancies with gestational diabetes to foreign-born women from both culturally and linguistically diverse and non-culturally and linguistically diverse backgrounds vs. Australian-born women. The same outcomes were also compared for pregnancies without gestational diabetes.

RESULTS

Foreign-born culturally and linguistically diverse women were more likely to undergo emergency Caesarean section, but less likely to have pre-eclampsia, an elective Caesarean section or induced labour than Australian-born women. Their infants were less likely to be large for gestational age, require resuscitation or be transferred to specialist care. These differences were also evident among pregnancies without gestational diabetes to culturally and linguistically diverse women, but did not exist between foreign-born non-culturally and linguistically diverse women and Australian-born women with gestational diabetes.

CONCLUSIONS

While gestational diabetes places women and infants at increased risk of adverse perinatal outcomes, these outcomes differed for foreign-born women from culturally and linguistically diverse backgrounds when compared with Australian-born women. Further investigation is required to elucidate why being foreign-born and culturally and linguistically diverse reduces the risk of several of these outcomes.

Elastic moduli of untreated, demineralized and deproteinized cortical bone: validation of a theoretical model of bone as an interpenetrating composite material

A theoretical experimentally based multi-scale model of the elastic response of cortical bone is presented. It portrays the hierarchical structure of bone as a composite with interpenetrating biopolymers (collagen and non-collagenous proteins) and minerals (hydroxyapatite), together with void spaces (porosity). The model involves a bottom-up approach and employs micromechanics and classical lamination theories of composite materials. Experiments on cortical bone samples from bovine femur include completely demineralized and deproteinized bones as well as untreated bone samples. Porosity and microstructure are characterized using optical and scanning electron microscopy, and micro-computed tomography. Compression testing is used to measure longitudinal and transverse elastic moduli of all three bone types. The characterization of structure and properties of these three bone states provides a deeper understanding of the contributions of the individual components of bone to its elastic response and allows fine tuning of modeling assumptions. Very good agreement is found between theoretical modeling and compression testing results, confirming the validity of the interpretation of bone as an interpenetrating composite material.

MicroRNA-23b promotes tolerogenic properties of dendritic cells in vitro through inhibiting Notch1/NF-κB signalling pathways

BACKGROUND

MicroRNAs (miRNAs) are known to regulate the inflammatory response in various cell types. However, the ability of miRNAs to modulate dendritic cells (DCs) function for allergen immunotherapy is unclear.

OBJECTIVE

To assess the role of miR-23b in the regulation of ovalbumin (OVA)-induced DC differentiation and function and to investigate the related molecular mechanisms.

METHODS

Bone marrow-derived dendritic cells (BMDCs) were generated from murine bone marrow progenitor cells and subsequently stimulated with OVA to examine the profile of miRNA expression. After transfection with miR-23b reagents, DCs were evaluated for endocytic ability, surface marker expression, cytokine secretion and CD4+ T-cell differentiation. The possible roles of the Notch and NF-κB signalling pathways were also evaluated. Human monocyte-derived dendritic cells (MDDCs) were similarly evaluated as well.

RESULTS

Significant upregulation of miR-23b was observed in BMDCs pulsed with OVA. Following miR-23b transfection, BMDCs showed decreased OVA uptake, increased IL-10 production, decreased IL-12 production and an enhanced capacity to promote FoxP3+ CD4+ T regulatory cells (Tregs) differentiation. In addition, inactivation of the Notch1 and NF-κB signalling pathways were observed. Conversely, inhibition of miR-23b in BMDCs resulted in the opposite effects. In human MDDCs, miRNA23b transfection similarly increased IL-10 and decreased IL-12 production, and that treated human MDDCs induced increased FoxP3+ CD4+ T cells.

CONCLUSION

Our findings provide evidence that miR-23b is capable of inducing tolerogenic DC activity and Treg responses in vitro through the inhibition of the Notch1 and NF-κB signalling pathways; thus, miR-23b might represent a therapeutic target for the management of allergic diseases.

Skeletal development and abnormalities of the vertebral column and of the fins in hatchery-reared turbot Scophthalmus maximus

To describe the skeletal development and abnormalities in turbot Scophthalmus maximus, samples were collected every day from hatching to 60 days after hatching (DAH). A whole-mount cartilage and bone-staining technique was used. Vertebral ontogeny started with the formation of anterior haemal arches at 5·1 mm standard length (L(S) ) c. 11 DAH, and was completed by the full attainment of parapophyses at 16·9 mm L(S) c. 31 DAH. Vertebral centra started to develop at 6·3 mm L(S) c. 16 DAH and ossification in all centra was visible at 11·0 mm L(S) c. 25 DAH. The caudal fin appeared at 5·1 mm L(S) c. 11 DAH and ossification was visible at 20·6 mm L(S) c. 37 DAH. The onset of dorsal and anal fin elements appeared at 5·8 mm L(S) c. 15 DAH and 6·3 mm L(S) c. 16 DAH, respectively. Ossifications of both dorsal fin and anal fin were visible at 20·6 mm L(S) c. 37 DAH. The pectorals were the only fins present before first feeding, their ossifications were completed at 23·5 mm L(S) c. 48 DAH. Pelvic fins began forming at 7·2 mm L(S) c. 19 DAH and calcification of the whole structure was visible at 19·8 mm L(S) c. 36 DAH. In the present study, 24 types of skeletal abnormalities were observed. About 51% of individuals presented skeletal abnormalities, and the highest occurrence was found in the haemal region of the vertebral column. As for each developmental stage, the most common abnormalities were in the dorsal fin during early metamorphic period (stage 2), vertebral fusion during climax metamorphosis (stage 3) and caudal fin abnormality during both late-metamorphic period (stage 4) and post-metamorphic period (stage 5). Such research will be useful for early detection of skeletal malformations during different growth periods of reared S. maximus.

Germ cells and fertilization differences among Japanese flounder Paralichthys olivaceus, summer flounder Paralichthys dentatus and their first and second generations

The morphology of gametes and the fertilization biology of Japanese flounder Paralichthys olivaceus (Po), summer flounder Paralichthys dentatus (Pd) and their hybrids were examined. Multiple generations (two hybrids: Po♀× Pd♂ (F1) and Pd♀× Po♂; two backcrosses: F1♀× Po♂ and F1♀× Pd♂) were obtained by artificial insemination. Comparison of egg ultrastructure among Po, Pd and F1 showed the morphology of micropyle region and the distribution density of pores were species specific. There were c. 100-200 accessory openings around the micropyle in Po, but not in Pd and F1. The zona radiata thickness and number of parallel bands were similar between F1 and Po, which were different from Pd. Comparison of spermatozoa ultrastructure revealed a close relationship between Po and Pd. Cytologically, the six crosses obeyed normal fertilization and cleavage processes, and only one male pronucleus was observed in a fertilized egg, indicating a monospermic fertilization pattern. Analysis of the time distribution from fertilization to first cleavage revealed an obvious delay at pronucleus fusion in the Pd × Po cross. The delay might indicate some cytoplasmic-nuclear incompatibility during the process of fertilization.

Design of a vector magnet for the measurements of anisotropic magnetoresistance and rotational magneto-optic Kerr effect

A vector magnet is designed and assembled with two electromagnets to produce a rotational magnetic field in any direction within a plane. This design allows a rotation of the magnetic field without a mechanical rotation of the magnets. The fast speed of the field rotation (~10 s for a complete 360° rotation) and the stability against mechanical vibration easily overcome the slow drifting effect in anisotropic magnetoresistance (AMR) and rotational magneto-optic Kerr effect (ROTMOKE) measurements. As an example we applied this vector magnet to carry out AMR and ROTMOKE measurements on epitaxial growth of Fe(10 nm)∕MgO(001) films. The result demonstrates the stability and high quality of the vector magnet in determining the magnetic anisotropy of magnetic thin films using AMR and ROTMOKE techniques.

Orthogonal-reference-pattern-modulated shift multiplexing for collinear holographic data storage

A novel hybrid shift multiplexing method for collinear holographic data storage (CHDS) by using orthogonal reference patterns (RPs) is proposed, analyzed, and demonstrated. For this method, holograms are multiplexed by not only shifting the media but also using different RPs. Compared with the traditional method, the shift pitch for the hybrid method is substantially reduced because of the selectivity introduced by different RPs. The interpage cross talk due to Bragg mismatch and degeneracy for multiplexing holograms in the same volume by using orthogonal RPs is also attenuated by utilizing the shift selectivity of the hologram. A 1.5 μm shift pitch is experimentally achieved by using three amplitude RPs in a system that would be 4.5 μm with only one RP. This new method offers an alternative to significantly increase the data density and transfer rate of the CHDS system given that the media has ideal properties.

Detection of the Treponema pallidum gene and variation of treponemal DNA load before and after therapy

We explored a genetic detection method for Treponema pallidum (TP) in the peripheral blood of infected patients to compare the loads of treponemal DNA before and after therapy and to see if this new technique enabled assessment of therapeutic effect and detection of serum resistance. Polymerase chain reaction was used for a qualitative detection of TP DNA in peripheral blood and then a semiquantitative method was adopted to estimate the load of TP DNA in blood, both before and after treatment of syphilis. Among 30 untreated patients, three cases were TP DNA-positive. Among 42 treated patients with demonstrated serum resistance, three cases were TP DNA-positive. Five cases in which the rapid plasma reagin had become negative had no detectable TP DNA in their peripheral blood. The TP DNA load in blood after treatment was significantly lower than that before therapy. We conclude that the detection of TP DNA in peripheral blood of TP-infected patients is not yet sufficiently sensitive, but we observed that TP DNA load declines significantly after treatment.