bluuebunny/crossref_metadata_2025 huggingface dataset:
Deletion Xq27.3q28 in female patient with global developmental delays and skewed X-inactivation
Authors: Marshall Lauren S , Simon Julie , Wood Tim , Peng Mei , Owen Renius , Feldman Gary S , Zaragoza Michael V
Published: May 2013

Background

Global developmental delay and mental retardation are associated with X-linked disorders including Hunter syndrome (mucopolysaccharidosis type II) and Fragile X syndrome (FXS). Single nucleotide mutations in the iduronate 2-sulfatase (IDS) gene at Xq28 most commonly cause Hunter syndrome while a CGG expansion in the FMR1 gene at Xq27.3 is associated with Fragile X syndrome. Gene deletions of the Xq27-28 region are less frequently found in either condition with rare reports in females. Additionally, an association between Xq27-28 deletions and skewed X-inactivation of the normal X chromosome observed in previous studies suggested a primary role of the Xq27-28 region in X-inactivation.

Case presentation

We describe the clinical, molecular and biochemical evaluations of a four year-old female patient with global developmental delay and a hemizygous deletion of Xq27.3q28 (144,270,614-154,845,961 bp), a 10.6 Mb region that contains >100 genes including IDS and FMR1. A literature review revealed rare cases with similar deletions that included IDS and FMR1 in females with developmental delay, variable features of Hunter syndrome, and skewed X-inactivation of the normal X chromosome. In contrast, our patient exhibited skewed X-inactivation of the deleted X chromosome and tested negative for Hunter syndrome.

Conclusions

This is a report of a female with a 10.6 Mb Xq27-28 deletion with skewed inactivation of the deleted X chromosome. Contrary to previous reports, our observations do not support a primary role of the Xq27-28 region in X-inactivation. A review of the genes in the deletion region revealed several potential genes that may contribute to the patient’s developmental delays, and sequencing of the active X chromosome may provide insight into the etiology of this clinical presentation.
Detection experiments with humans implicate visual predation as a driver of colour polymorphism dynamics in pygmy grasshoppers
Authors: Karpestam Einat , Merilaita Sami , Forsman Anders
Published: May 2013

Background

Animal colour patterns offer good model systems for studies of biodiversity and evolution of local adaptations. An increasingly popular approach to study the role of selection for camouflage for evolutionary trajectories of animal colour patterns is to present images of prey on paper or computer screens to human ‘predators’. Yet, few attempts have been made to confirm that rates of detection by humans can predict patterns of selection and evolutionary modifications of prey colour patterns in nature. In this study, we first analyzed encounters between human ‘predators’ and images of natural black, grey and striped colour morphs of the polymorphic Tetrix subulata pygmy grasshoppers presented on background images of unburnt, intermediate or completely burnt natural habitats. Next, we compared detection rates with estimates of capture probabilities and survival of free-ranging grasshoppers, and with estimates of relative morph frequencies in natural populations.

Results

The proportion of grasshoppers that were detected and time to detection depended on both the colour pattern of the prey and on the type of visual background. Grasshoppers were detected more often and faster on unburnt backgrounds than on 50% and 100% burnt backgrounds. Striped prey were detected less often than grey or black prey on unburnt backgrounds; grey prey were detected more often than black or striped prey on 50% burnt backgrounds; and black prey were detected less often than grey prey on 100% burnt backgrounds. Rates of detection mirrored previously reported rates of capture by humans of free-ranging grasshoppers, as well as morph specific survival in the wild. Rates of detection were also correlated with frequencies of striped, black and grey morphs in samples of T. subulata from natural populations that occupied the three habitat types used for the detection experiment.

Conclusions

Our findings demonstrate that crypsis is background-dependent, and implicate visual predation as an important driver of evolutionary modifications of colour polymorphism in pygmy grasshoppers. Our study provides the clearest evidence to date that using humans as ‘predators’ in detection experiments may provide reliable information on the protective values of prey colour patterns and of natural selection and microevolution of camouflage in the wild.
A hybrid seasonal prediction model for tuberculosis incidence in China
Authors: Cao Shiyi , Wang Feng , Tam Wilson , Tse Lap Ah , Kim Jean Hee , Liu Junan , Lu Zuxun
Published: May 2013

Background

Tuberculosis (TB) is a serious public health issue in developing countries. Early prediction of TB epidemic is very important for its control and intervention. We aimed to develop an appropriate model for predicting TB epidemics and analyze its seasonality in China.

Methods

Data of monthly TB incidence cases from January 2005 to December 2011 were obtained from the Ministry of Health, China. A seasonal autoregressive integrated moving average (SARIMA) model and a hybrid model which combined the SARIMA model and a generalized regression neural network model were used to fit the data from 2005 to 2010. Simulation performance parameters of mean square error (MSE), mean absolute error (MAE) and mean absolute percentage error (MAPE) were used to compare the goodness-of-fit between these two models. Data from 2011 TB incidence data was used to validate the chosen model.

Results

Although both two models could reasonably forecast the incidence of TB, the hybrid model demonstrated better goodness-of-fit than the SARIMA model. For the hybrid model, the MSE, MAE and MAPE were 38969150, 3406.593 and 0.030, respectively. For the SARIMA model, the corresponding figures were 161835310, 8781.971 and 0.076, respectively. The seasonal trend of TB incidence is predicted to have lower monthly incidence in January and February and higher incidence from March to June.

Conclusions

The hybrid model showed better TB incidence forecasting than the SARIMA model. There is an obvious seasonal trend of TB incidence in China that differed from other countries.
Effects of co-administration of candesartan with pioglitazone on inflammatory parameters in hypertensive patients with type 2 diabetes mellitus: a preliminary report
Authors: Suzuki Hirofumi , Sakamoto Masaya , Hayashi Takeshi , Iuchi Hiroyuki , Ohashi Kennosuke , Isaka Tsuyoshi , Sakamoto Noriko , Kayama Yosuke , Tojo Katsuyoshi , Yoshimura Michihiro , Utsunomiya Kazunori
Published: May 2013

Background

Angiotensin receptor blockers (ARBs) are reported to provide direct protection to many organs by controlling inflammation and decreasing oxidant stress. Pioglitazone, an anti-diabetic agent that improves insulin resistance, was also reported to decrease inflammation and protect against atherosclerosis. This study aimed to evaluate the utility of combination therapy with both medicines from the viewpoint of anti-inflammatory effects.

Methods

We administered candesartan (12 mg daily) and pioglitazone (15 mg daily) simultaneously for 6 months to hypertensive patients with type 2 diabetes mellitus (T2DM) and evaluated whether there were improvements in the serum inflammatory parameters of high-molecular-weight adiponectin (HMW-ADN), plasminogen activator inhibitor-1 (PAI-1), highly sensitive C-reactive protein (Hs-CRP), vascular cell adhesion molecule-1 (VCAM-1), and urinary-8-hydroxydeoxyguanosine (U-8-OHdG). We then analyzed the relationship between the degree of reductions in blood pressure and HbA1c values and improvements in inflammatory factors. Furthermore, we analyzed the relationship between pulse pressure and the degree of lowering of HbA1c and improvements in inflammatory factors. Finally, we examined predictive factors in patients who received benefits from the co-administration of candesartan with pioglitazone from the viewpoint of inflammatory factors.

Results

After 6 months of treatment, in all patients significant improvements from baseline values were observed in HMW-ADN and PAI-1 but not in VCAM-1, Hs-CRP, and U-8-OHdG. Changes in HbA1c were significantly correlated with changes in HMW-ADN and PAI-1 in all patients, but changes in blood pressure were not correlated with any of the parameters examined. Correlation and multilinear regression analyses were performed to determine which factors could best predict changes in HbA1c. Interestingly, we found a significant positive correlation of pulse pressure values at baseline with changes in HbA1c.

Conclusions

Our data suggest that the pulse pressure value at baseline is a key predictive factor of changes in HbA1c. Co-administration of candesartan with pioglitazone, which have anti-inflammatory (changes in HMW-ADN and PAI-1) effects and protective effects on organs, could be an effective therapeutic strategy for treating hypertensive patients with type 2 diabetes mellitus.

Trial registration

UMIN-CTR: UMIN000010142
Use of a Tn5-based transposon system to create a cost-effective Zymomonas mobilis for ethanol production from lignocelluloses
Authors: Zhang Xi , Wang Tianyv , Zhou Wen , Jia Xianghui , Wang Haoyong
Published: May 2013

Background

Current methods of ethanol production from lignocelluloses generate a mixture of sugars, primarily glucose and xylose; the fermentation cells are always exposed to stresses like high temperature and low nutritional conditions that affect their growth and productivity. Stress-tolerant strains capable of using both glucose and xylose to produce ethanol with high yield are highly desirable.

Results

A recombinant Zymomonas mobilis (Z. mobilis) designated as HYMX was constructed by integrating seven genes (Pfu-sHSP, yfdZ, metB, xylA, xylB, tktA and talB) into the genome of Z. mobilis CP4 (CP4) via Tn5 transposon in the present study. The small heat shock protein gene (Pfu-sHSP) from Pyrococcus furious (P. furious) was used to increase the heat-tolerance, the yfdZ and metB genes from E. coli were used to decrease the nutritional requirement. To overcome the bottleneck of CP4 being unable to use pentose, xylose catabolic genes (xylA, xylB, tktA and talB) from E. coli were integrated into CP4 also for construction of the xylose utilizing metabolic pathway.

Conclusions

The genomic integration confers on Z. mobilis the ability to grow in medium containing xylose as the only carbon source, and to grow in simple chemical defined medium without addition of amino acid. The HYMX demonstrated not only the high tolerance to unfavorable stresses like high temperature and low nutrient, but also the capability of converting both glucose and xylose to ethanol with high yield at high temperature. What’s more, these genetic characteristics were stable up to 100 generations on nonselective medium. Although significant improvements were achieved, yeast extract is needed for ethanol production.
Modification of glucose import capacity in Escherichia coli: physiologic consequences and utility for improving DNA vaccine production
Authors: Fuentes Laura G , Lara Alvaro R , Martínez Luz M , Ramírez Octavio T , Martínez Alfredo , Bolívar Francisco , Gosset Guillermo
Published: May 2013

Background

The bacterium Escherichia coli can be grown employing various carbohydrates as sole carbon and energy source. Among them, glucose affords the highest growth rate. This sugar is nowadays widely employed as raw material in industrial fermentations. When E. coli grows in a medium containing non-limiting concentrations of glucose, a metabolic imbalance occurs whose main consequence is acetate secretion. The production of this toxic organic acid reduces strain productivity and viability. Solutions to this problem include reducing glucose concentration by substrate feeding strategies or the generation of mutant strains with impaired glucose import capacity. In this work, a collection of E. coli strains with inactive genes encoding proteins involved in glucose transport where generated to determine the effects of reduced glucose import capacity on growth rate, biomass yield, acetate and production of an experimental plasmid DNA vaccine (pHN).

Results

A group of 15 isogenic derivatives of E. coli W3110 were generated with single and multiple deletions of genes encoding glucose, mannose, beta-glucoside, maltose and N-acetylglucosamine components of the phosphoenolpyruvate:sugar phosphotransferase system (PTS), as well as the galactose symporter and the Mgl galactose/glucose ABC transporter. These strains were characterized by growing them in mineral salts medium supplemented with 2.5 g/L glucose. Maximum specific rates of glucose consumption (q

s
) spanning from 1.33 to 0.32 g/g h were displayed by the group of mutants and W3110, which resulted in specific growth rates ranging from 0.65-0.18 h-1. Acetate accumulation was reduced or abolished in cultures with all mutant strains. W3110 and five selected mutant derivatives were transformed with pHN. A 3.2-fold increase in pHN yield on biomass was observed in cultures of a mutant strain with deletion of genes encoding the glucose and mannose PTS components, as well as Mgl.

Conclusions

The group of E. coli mutants generated in this study displayed a reduction or elimination of overflow metabolism and a linear correlation between q

s
and the maximum specific growth rate as well as the acetate production rate. By comparing DNA vaccine production parameters among some of these mutants, it was possible to identify a near-optimal glucose import rate value for this particular application. The strains employed in this study should be a useful resource for studying the effects of different predefined q

s
values on production capacity for various biotechnological products.
Screening and identification of genetic loci involved in producing more/denser inclusion bodies in Escherichia coli
Authors: Pandey Neeraj , Sachan Annapurna , Chen Qi , Ruebling-Jass Kristin , Bhalla Ritu , Panguluri Kiran Kumar , Rouviere Pierre E , Cheng Qiong
Published: May 2013

Background

Many proteins and peptides have been used in therapeutic or industrial applications. They are often produced in microbial production hosts by fermentation. Robust protein production in the hosts and efficient downstream purification are two critical factors that could significantly reduce cost for microbial protein production by fermentation. Producing proteins/peptides as inclusion bodies in the hosts has the potential to achieve both high titers in fermentation and cost-effective downstream purification. Manipulation of the host cells such as overexpression/deletion of certain genes could lead to producing more and/or denser inclusion bodies. However, there are limited screening methods to help to identify beneficial genetic changes rendering more protein production and/or denser inclusion bodies.

Results

We report development and optimization of a simple density gradient method that can be used for distinguishing and sortingE. colicells with different buoyant densities. We demonstrate utilization of the method to screen genetic libraries to identify a) expression ofglyQSloci on plasmid that increased expression of a peptide of interest as well as the buoyant density of inclusion body producingE. colicells; and b) deletion of a hostgltAgene that increased the buoyant density of the inclusion body produced in theE. colicells.

Conclusion

A novel density gradient sorting method was developed to screen genetic libraries. Beneficial host genetic changes could be exploited to improve recombinant protein expression as well as downstream protein purification.
Assessment of potential anti-cancer stem cell activity of marine algal compounds using an in vitro mammosphere assay
Authors: de la Mare Jo-Anne , Sterrenberg Jason N , Sukhthankar Mugdha G , Chiwakata Maynard T , Beukes Denzil R , Blatch Gregory L , Edkins Adrienne L
Published: May 2013

Background

The cancer stem cell (CSC) theory proposes that tumours arise from and are sustained by a subpopulation of cells with both cancer and stem cell properties. One of the key hallmarks of CSCs is the ability to grow anchorage-independently under serum-free culture conditions resulting in the formation of tumourspheres. It has further been reported that these cells are resistant to traditional chemotherapeutic agents.

Methods

In this study, the tumoursphere assay was validated in MCF-7 cells and used to screen novel marine algal compounds for potential anti-cancer stem cell (CSC) activity in vitro.

Results

MCF-7 breast cancer cells were observed to generate tumourspheres or mammospheres after 3-5 days growth in anchorage-independent conditions and an apparent enrichment in potential CSCs was observed by an increase in the proportion of CD44high/CD24low marker-bearing cells and Oct4 expression compared to those in the bulk population grown in regular adherent conditions. Using this assay, a set of algal metabolites was screened for the ability to inhibit mammosphere development as a measure of potential anti-CSC activity. We report that the polyhalogenated monoterpene stereoisomers RU017 and RU018 isolated from the red alga Plocamium cornutum, both of which displayed no cytotoxicity against either adherent MCF-7 breast cancer or MCF-12A non-transformed breast epithelial cells, were able to prevent MCF-7 mammosphere formation in vitro. On the other hand, neither the brown algal carotenoid fucoxanthin nor the chemotherapeutic paclitaxel, both of which were toxic to adherent MCF-7 and MCF-12A cells, were able to inhibit mammosphere formation. In fact, pre-treatment with paclitaxel appeared to enhance mammosphere formation and development, a finding which is consistent with the reported resistance of CSCs to traditional chemotherapeutic agents.

Conclusion

Due to the proposed clinical significance of CSC in terms of tumour initiation and metastasis, the identification of agents able to inhibit this subpopulation has clinical significance.
Flaxseed oil and alpha-lipoic acid combination ameliorates hepatic oxidative stress and lipid accumulation in comparison to lard
Authors: Xu Jiqu , Gao Hui , Song Lin , Yang Wei , Chen Chang , Deng Qianchun , Huang Qingde , Yang Jin’e , Huang Fenghong
Published: May 2013

Background

Intake of high-fat diet is associated with increased non-alcoholic fatty liver disease (NAFLD). Hepatic lipid accumulation and oxidative stress are key pathophysiological mechanisms in NAFLD. Both flaxseed oil (FO) and α-lipoic acid (LA) exert potential benefit to NAFLD. The aim of this study was to determine the effect of the combination of FO and LA on hepatic lipid accumulation and oxidative stress in rats induced by high-fat diet.

Methods

LA was dissolved in flaxseed oil to a final concentration of 8 g/kg (FO + LA). The rodent diet contained 20% fat. One-fifth of the fat was soybean oil and the others were lard (control group), or 75% lard and 25% FO + LA (L-FO + LA group), or 50% lard and 50% FO + LA (M-FO + LA group), or FO + LA (H-FO + LA group). Male Sprague–Dawley rats were fed for 10 weeks and then killed for liver collection.

Results

Intake of high-fat lard caused a significant hepatic steatosis. Replacement with FO + LA was effective in reducing steatosis as well as total triglyceride and total cholesterol contents in liver. The combination of FO and LA also significantly elevated hepatic antioxidant defense capacities, as evaluated by the remarkable increase in the activities of SOD, CAT and GPx as well as the level of GSH, and the significant decline in lipid peroxidation.

Conclusion

The combination of FO and LA may contribute to prevent fatty livers such as NAFLD by ameliorating hepatic lipid accumulation and oxidative stress.
The effect of feeding a low iron diet prior to and during gestation on fetal and maternal iron homeostasis in two strains of rat
Authors: Cornock Ruth , Gambling Lorraine , Langley-Evans Simon C , McArdle Harry J , McMullen Sarah
Published: May 2013

Background

Iron deficiency anaemia during pregnancy is a global problem, with short and long term consequences for maternal and child health. Animal models have demonstrated that the developing fetus is vulnerable to maternal iron restriction, impacting on postnatal metabolic and blood pressure regulation. Whilst long-term outcomes are similar across different models, the commonality in mechanistic events across models is unknown. This study examined the impact of iron deficiency on maternal and fetal iron homeostasis in two strains of rat.

Methods

Wistar (n=20) and Rowett Hooded Lister (RHL, n=19) rats were fed a control or low iron diet for 4 weeks prior to and during pregnancy. Tissues were collected at day 21 of gestation for analysis of iron content and mRNA/protein expression of regulatory proteins and transporters.

Results

A reduction in maternal liver iron content in response to the low iron diet was associated with upregulation of transferrin receptor expression and a reduction in hepcidin expression in the liver of both strains, which would be expected to promote increased iron absorption across the gut and increased turnover of iron in the liver. Placental expression of transferrin and DMT1+IRE were also upregulated, indicating adaptive responses to ensure availability of iron to the fetus. There were considerable differences in hepatic maternal and fetal iron content between strains. The higher quantity of iron present in livers from Wistar rats was not explained by differences in expression of intestinal iron transporters, and may instead reflect greater materno-fetal transfer in RHL rats as indicated by increased expression of placental iron transporters in this strain.

Conclusions

Our findings demonstrate substantial differences in iron homeostasis between two strains of rat during pregnancy, with variable impact of iron deficiency on the fetus. Whilst common developmental processes and pathways have been observed across different models of nutrient restriction during pregnancy, this study demonstrates differences in maternal adaptation which may impact on the trajectory of the programmed response.
The engagement of CTLA-4 on primary melanoma cell lines induces antibody-dependent cellular cytotoxicity and TNF-α production
Authors: Laurent Stefania , Queirolo Paola , Boero Silvia , Salvi Sandra , Piccioli Patrizia , Boccardo Simona , Minghelli Simona , Morabito Anna , Fontana Vincenzo , Pietra Gabriella , Carrega Paolo , Ferrari Nicoletta , Tosetti Francesca , Chang Lung-Ji , Mingari Maria Cristina , Ferlazzo Guido , Poggi Alessandro , Pistillo Maria Pia
Published: May 2013

Background

CTLA-4 (Cytotoxic T lymphocyte antigen-4) is traditionally known as a negative regulator of T cell activation. The blocking of CTLA-4 using human monoclonal antibodies, such as Ipilimumab, is currently used to relieve CTLA-4-mediated inhibition of anti-tumor immune response in metastatic melanoma. Herein, we have analyzed CTLA-4 expression and Ipilimumab reactivity on melanoma cell lines and tumor tissues from cutaneous melanoma patients. Then, we investigated whether Ipilimumab can trigger innate immunity in terms of antibody dependent cellular cytotoxicity (ADCC) or Tumor Necrosis Factor (TNF)-α release. Finally, a xenograft murine model was set up to determinein vivothe effects of Ipilimumab and NK cells on melanoma.

Methods

CTLA-4 expression and Ipilimumab reactivity were analyzed on 17 melanoma cell lines (14 primary and 3 long-term cell lines) by cytofluorimetry and on 33 melanoma tissues by immunohistochemistry. CTLA-4 transcripts were analyzed by quantitative RT-PCR. Soluble CTLA-4 and TNF-α were tested by ELISA. Peripheral blood mononuclear cells (PBMC), NK and γδT cells were tested in ADCC assay with Ipilimumab and melanoma cell lines.TNF-α release was analyzed in NK-melanoma cell co-cultures in the presence of ipilimumab.In vivoexperiments of xenotransplantation were carried out in NOD/SCID mice. Results were analyzed using unpaired Student’s t-test.

Results

All melanoma cell lines expressed mRNA and cytoplasmic CTLA-4 but surface reactivity with Ipilimumab was quite heterogeneous. Accordingly, about 2/3 of melanoma specimens expressed CTLA-4 at different level of intensity.

Ipilimumab triggered, via FcγReceptorIIIA (CD16), ex vivo NK cells as well as PBMC, IL-2 activated NK and γδT cells to ADCC of CTLA-4+melanoma cells. No ADCC was detected upon interaction with CTLA-4-FO-1 melanoma cell line. TNF-α was released upon interaction of NK cells with CTLA-4+melanoma cell lines. Remarkably, Ipilimumab neither affected proliferation and viability nor triggered ADCC of CTLA-4+T lymphocytes. In a chimeric murine xenograft model, the co-engraftment of Ipilimumab-treated melanoma cells with human allogeneic NK cells delayed and significantly reduced tumor growth, as compared to mice receiving control xenografts.

Conclusions

Our studies demonstrate that Ipilimumab triggers effector lymphocytes to cytotoxicity and TNF-α release. These findings suggest that Ipilimumab, besides blocking CTLA-4, can directly activate the elimination of CTLA-4+melanomas.
First-principles investigation on the segregation of Pd at LaFe1-xPd
x
O3-y surfaces
Authors: Tian Zhi-xue , Uozumi Akifumi , Hamada Ikutaro , Yanagisawa Susumu , Kizaki Hidetoshi , Inagaki Kouji , Morikawa Yoshitada
Published: May 2013

First-principles calculations were performed to investigate the effect of Pd concentration and oxygen vacancies on the stability of Pd at LaFeO3 surfaces. We found a much stronger tendency of Pd to segregate by taking the aggregation of Pd at LaFe1-x
Pd
x
O3-y
surfaces into consideration, resulting in a pair of Pd-Pd around a vacancy. Moreover, we predicted that one oxygen-vacancy-containing FeO2-terminated surfaces would be stable at high temperatures by comparing the stability of LaFe1-x
Pd
x
O3-y
surfaces, which further supports our previous conclusion that a Pd-containing perovskite catalyst should be calcined at 1,073 K or higher temperatures in air to enhance the segregation of Pd in the vicinity of surfaces to rapidly transform the Pd catalyst from oxidized to reduced states on the perovskite support.
Developing high-transmittance heterojunction diodes based on NiO/TZO bilayer thin films
Authors: Huang Chia-Cheng , Wang Fang-Hsing , Wu Chia-Ching , Huang Hong-Hsin , Yang Cheng-Fu
Published: May 2013

In this study, radio frequency magnetron sputtering was used to deposit nickel oxide thin films (NiO, deposition power of 100 W) and titanium-doped zinc oxide thin films (TZO, varying deposition powers) on glass substrates to form p(NiO)-n(TZO) heterojunction diodes with high transmittance. The structural, optical, and electrical properties of the TZO and NiO thin films and NiO/TZO heterojunction devices were investigated with scanning electron microscopy, X-ray diffraction (XRD) patterns, UV-visible spectroscopy, Hall effect analysis, and current-voltage (I-V) analysis. XRD analysis showed that only the (111) diffraction peak of NiO and the (002) and (004) diffraction peaks of TZO were observable in the NiO/TZO heterojunction devices, indicating that the TZO thin films showed a good c-axis orientation perpendicular to the glass substrates. When the sputtering deposition power for the TZO thin films was 100, 125, and 150 W, the I-V characteristics confirmed that a p-n junction characteristic was successfully formed in the NiO/TZO heterojunction devices. We show that the NiO/TZO heterojunction diode was dominated by the space-charge limited current theory.
Cytotoxicity and variant cellular internalization behavior of water-soluble sulfonated nanographene sheets in liver cancer cells
Authors: Corr Stuart J , Raoof Mustafa , Cisneros Brandon T , Kuznetsov Oleksandr , Massey Katheryn , Kaluarachchi Warna D , Cheney Matthew A , Billups Edward W , Wilson Lon J , Curley Steven A
Published: May 2013

Highly exfoliated sulfonated graphene sheets (SGSs), an alternative to graphene oxide and graphene derivatives, were synthesized, characterized, and applied to liver cancer cells in vitro. Cytotoxicity profiles were obtained using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, WST-1[2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, and lactate dehydrogenase release colorimetric assays. These particles were found to be non-toxic across the concentration range of 0.1 to 10 μg/ml. Internalization of SGSs was also studied by means of optical and electron microscopy. Although not conclusive, high-resolution transmission and scanning electron microscopy revealed variant internalization behaviors where some of the SGS became folded and compartmentalized into tight bundles within cellular organelles. The ability for liver cancer cells to internalize, fold, and compartmentalize graphene structures is a phenomenon not previously documented for graphene cell biology and should be further investigated.
Phospholipase C-Related but Catalytically Inactive Protein Modulates Pain Behavior in a Neuropathic Pain Model in Mice
Authors: Kitayama Tomoya , Morita Katsuya , Sultana Rizia , Kikushige Nami , Mgita Keisuke , Ueno Shinya , Hirata Masato , Kanematsu Takashi
Published: May 2013

Background

An inositol 1, 4, 5-trisphosphate binding protein, comprising 2 isoforms termed PRIP-1 and PRIP-2, was identified as a novel modulator for GABAA receptor trafficking. It has been reported that naive PRIP-1 knockout mice have hyperalgesic responses.

Findings

To determine the involvement of PRIP in pain sensation, a hind paw withdrawal test was performed before and after partial sciatic nerve ligation (PSNL) in PRIP-1 and PRIP-2 double knockout (DKO) mice. We found that naive DKO mice exhibited normal pain sensitivity. However, DKO mice that underwent PSNL surgery showed increased ipsilateral paw withdrawal threshold. To further investigate the inverse phenotype in PRIP-1 KO and DKO mice, we produced mice with specific siRNA-mediated knockdown of PRIPs in the spinal cord. Consistent with the phenotypes of KO mice, PRIP-1 knockdown mice showed allodynia, while PRIP double knockdown (DKD) mice with PSNL showed decreased pain-related behavior. This indicates that reduced expression of both PRIPs in the spinal cord induces resistance towards a painful sensation. GABAA receptor subunit expression pattern was similar between PRIP-1 KO and DKO spinal cord, while expression of K+-Cl-cotransporter-2 (KCC2), which controls the balance of neuronal excitation and inhibition, was significantly upregulated in DKO mice. Furthermore, in the DKD PSNL model, an inhibitor-induced KCC2 inhibition exhibited an altered phenotype from painless to painful sensations.

Conclusions

Suppressed expression of PRIPs induces an elevated expression of KCC2 in the spinal cord, resulting in inhibition of nociception and amelioration of neuropathic pain in DKO mice.
Robenacoxib versus meloxicam for the management of pain and inflammation associated with soft tissue surgery in dogs: a randomized, non-inferiority clinical trial
Authors: Gruet Philippe , Seewald Wolfgang , King Jonathan N
Published: May 2013

Background

Non-steroidal anti-inflammatory drugs (NSAIDs) are used routinely to control pain and inflammation after surgery in dogs. Robenacoxib is a new NSAID with high selectivity for the cyclo-oxygenase (COX)-2 isoform of COX. The objective of this study was to evaluate the efficacy and tolerability of robenacoxib for the management of peri-operative pain and inflammation associated with soft tissue surgery in dogs. The study was a prospective, randomized, blinded, positive-controlled, non-inferiority, multi-center clinical trial. A total of 174 dogs undergoing major soft tissue surgery were included and randomly allocated in a 2:1 ratio to receive either robenacoxib (n = 118) or the positive control, meloxicam (n = 56). Each dog received an initial dose subcutaneously prior to surgery (robenacoxib 2 mg/kg, meloxicam 0.2 mg/kg), followed by daily oral doses (robenacoxib 1–2 mg/kg, meloxicam 0.1 mg/kg) for 12 days (range 10–14) after surgery. Pain and inflammation were assessed subjectively using the Glasgow Composite Pain Scale (GCPS) by clinicians as the primary end point and additional evaluations by the clinicians and animal owners as secondary endpoints.

Results

Both treatments provided similar pain control, with no significant differences between groups for any efficacy variable using non-parametric analyses (Mann–WhitneyUtest). In no dog was analgesic rescue therapy administered. Non-inferior efficacy of robenacoxib compared to meloxicam was demonstrated statistically for the primary and all secondary endpoints using parametric analysis of variance, although the data were not normally distributed even after log transformation. For the primary endpoint (reciprocal of the modified GCPS score), the relative efficacy of robenacoxib/meloxicam was 1.12 with a 95% confidence interval of 0.97-1.29.

Both treatments were well tolerated and did not affect buccal mucosal bleeding time.

Conclusion

A treatment regimen of robenacoxib by subcutaneous injection followed by oral tablets had good tolerability and non-inferior efficacy compared to meloxicam for the management of peri-operative pain and inflammation associated with soft tissue surgery in dogs.
Mapping condition-dependent regulation of metabolism in yeast through genome-scale modeling
Authors: Österlund Tobias , Nookaew Intawat , Bordel Sergio , Nielsen Jens
Published: May 2013

Background

The genome-scale metabolic model of Saccharomyces cerevisiae
, first presented in 2003, was the first genome-scale network reconstruction for a eukaryotic organism. Since then continuous efforts have been made in order to improve and expand the yeast metabolic network.

Results

Here we present iTO977, a comprehensive genome-scale metabolic model that contains more reactions, metabolites and genes than previous models. The model was constructed based on two earlier reconstructions, namely iIN800 and the consensus network, and then improved and expanded using gap-filling methods and by introducing new reactions and pathways based on studies of the literature and databases. The model was shown to perform well both for growth simulations in different media and gene essentiality analysis for single and double knock-outs. Further, the model was used as a scaffold for integrating transcriptomics, and flux data from four different conditions in order to identify transcriptionally controlled reactions, i.e. reactions that change both in flux and transcription between the compared conditions.

Conclusion

We present a new yeast model that represents a comprehensive up-to-date collection of knowledge on yeast metabolism. The model was used for simulating the yeast metabolism under four different growth conditions and experimental data from these four conditions was integrated to the model. The model together with experimental data is a useful tool to identify condition-dependent changes of metabolism between different environmental conditions.
Mutation of the Xylanase regulator 1 causes a glucose blind hydrolase expressing phenotype in industrially used Trichoderma strains
Authors: Derntl Christian , Gudynaite-Savitch Loreta , Calixte Sophie , White Theresa , Mach Robert L , Mach-Aigner Astrid R
Published: May 2013

Background

Trichoderma reesei is an organism involved in degradation of (hemi)cellulosic biomass. Consequently, the corresponding enzymes are commonly used in different types of industries, and recently gained considerable importance for production of second-generation biofuel. Many industrial T. reesei strains currently in use are derived from strain Rut-C30, in which cellulase and hemicellulase expression is released from carbon catabolite repression. Nevertheless, inducing substances are still necessary for a satisfactory amount of protein formation.

Results

Here, we report on a T. reesei strain, which exhibits a very high level of xylanase expression regardless if inducing substances (e.g. D-xylose, xylobiose) are used. We found that a single point mutation in the gene encoding the Xylanase regulator 1 (Xyr1) is responsible for this strong deregulation of endo-xylanase expression and, moreover, a highly elevated basal level of cellulase expression. This point mutation is localized in a domain that is common in binuclear zinc cluster transcription factors. Only the use of sophorose as inducer still leads to a slight induction of cellulase expression. Under all tested conditions, the formation of cbh1 and cbh2 transcript level strictly follows the transcript levels of xyr1. The correlation of xyr1 transcript levels and cbh1/cbh2 transcript levels and also their inducibility via sophorose is not restricted to this strain, but occurs in all ancestor strains up to the wild-type QM6a.

Conclusions

Engineering a key transcription factor of a target regulon seems to be a promising strategy in order to increase enzymes yields independent of the used substrate or inducer. The regulatory domain where the described mutation is located is certainly an interesting research target for all organisms that also depend so far on certain inducing conditions.
Bioefficacy of long-lasting insecticidal nets against pyrethroid-resistant populations of Anopheles gambiae s.s. from different malaria transmission zones in Uganda
Authors: Okia Michael , Ndyomugyenyi Richard , Kirunda James , Byaruhanga Anatol , Adibaku Seraphine , Lwamafa Denis K , Kironde Fred
Published: May 2013

Background

There are major concerns over sustaining the efficacy of current malaria vector control interventions given the rapid spread of resistance, particularly to pyrethroids. This study assessed the bioefficacy of five WHO-recommended long-lasting insecticidal nets (LLINs) against pyrethroid-resistant Anopheles gambiae field populations from Uganda.

Methods

Adult An. gambiae from Lira, Tororo, Wakiso and Kanungu districts were exposed to permethrin (0.75%) or deltamethrin (0.05%) in standard WHO susceptibility tests. Cone bioassays were used to measure the bioefficacy of four mono-treated LLINs (Olyset®, Interceptor®, Netprotect® and PermaNet® 2.0) and one combination LLIN (PermaNet® 3.0) against the four mosquito populations. Wireball assays were similarly conducted to determine knockdown rates. Species composition and kdr mutation frequency were determined for a sample of mosquitoes from each population. Chemical assays confirmed that test nets fell within target dose ranges.

Results

Anopheles gambiae s.s. predominated at all four sites (86 - 99% of Anopheles spp.) with moderate kdr L1014S allelic frequency (0.34 – 0.37). Confirmed or possible resistance to both permethrin and deltamethrin was identified for all four test populations. Reduced susceptibility to standard LLINs was observed for all four populations, with mortality rates as low as 45.8% even though the nets were unused. The combination LLIN PermaNet®3.0 showed the highest overall bioefficacy against all four An. gambiae s.l. populations (98.5 - 100% mortality). Wireball assays provided a more sensitive indicator of comparative bioefficacy, and PermaNet 3.0 was again associated with the highest bioefficacy against all four populations (76.5 – 91.7% mortality after 30 mins).

Conclusions

The bioefficacy of mono-treated LLINs against pyrethroid-resistant field populations of An. gambiae varied by LLIN type and mosquito population, indicating that certain LLINs may be more suitable than others at particular sites. In contrast, the combination LLIN PermaNet 3.0 performed optimally against the four An. gambiae populations tested. The observed reduced susceptibility of malaria vectors to mono-treated LLINs is of particular concern, especially considering all nets were unused. With ongoing scale-up of insecticidal tools in the advent of increasing resistance, it is essential that those interventions with proven enhanced efficacy are given preference particularly in areas with high resistance.
A human Dravet syndrome model from patient induced pluripotent stem cells
Authors: Higurashi Norimichi , Uchida Taku , Lossin Christoph , Misumi Yoshio , Okada Yohei , Akamatsu Wado , Imaizumi Yoichi , Zhang Bo , Nabeshima Kazuki , Mori Masayuki X , Katsurabayashi Shutaro , Shirasaka Yukiyoshi , Okano Hideyuki , Hirose Shinichi
Published: May 2013

Background

Dravet syndrome is a devastating infantile-onset epilepsy syndrome with cognitive deficits and autistic traits caused by genetic alterations in SCN1A gene encoding the α-subunit of the voltage-gated sodium channel Nav1.1. Disease modeling using patient-derived induced pluripotent stem cells (iPSCs) can be a powerful tool to reproduce this syndrome’s human pathology. However, no such effort has been reported to date. We here report a cellular model for DS that utilizes patient-derived iPSCs.

Results

We generated iPSCs from a Dravet syndrome patient with a c.4933C>T substitution in SCN1A, which is predicted to result in truncation in the fourth homologous domain of the protein (p.R1645*). Neurons derived from these iPSCs were primarily GABAergic (>50%), although glutamatergic neurons were observed as a minor population (<1%). Current-clamp analyses revealed significant impairment in action potential generation when strong depolarizing currents were injected.

Conclusions

Our results indicate a functional decline in Dravet neurons, especially in the GABAergic subtype, which supports previous findings in murine disease models, where loss-of-function in GABAergic inhibition appears to be a main driver in epileptogenesis. Our data indicate that patient-derived iPSCs may serve as a new and powerful research platform for genetic disorders, including the epilepsies.
DNMT1 genetic polymorphisms affect breast cancer risk in the central European Caucasian population
Authors: Kullmann Kathrin , Deryal Mustafa , Ong Mei Fang , Schmidt Werner , Mahlknecht Ulrich
Published: May 2013

Introduction

DNA methylation of CpG islands within the promoter region of genes is an epigenetic modification with an important role in the development of cancer and it is typically mediated by DNA methyltransferases (DNMTs). In cancer cells, global hypomethylation of the genome as a whole and regional hypermethylation of CpG islands have been reported. Four groups of DNMTs have been identified: DNMT1, DNMT2 (TRDMT1), DNMT3A and DNMT3B. DNMT2 uses the catalytic mechanism of DNMTs, but does in fact methylate RNA. Little is known about the significance of these genes in human breast cancer. In the study presented herein, we analyzed five distinct DNMT single SNPs with regard to potential associations with breast cancer risk.

Case description

In this study, we genotyped 221 female Caucasian breast cancer patients and 221 female Caucasian healthy controls, and we used five allele-specific real-time polymerase chain reaction (qPCR) assays. We selected one locus within the DNMT1 gene and two loci within the DNMT3A and DNMT3B genes, respectively. Statistics were calculated using the chi-squared and Fisher’s exact tests, and correlated with clinical parameters such as age, diagnosis, histology, TNM stage, hormonal receptor status, human epidermal growth factor receptor 2 (HER2) status, response to treatment and survival. Statistically significant results were obtained for correlations with the DNMT1 gene.

Discussion and Evaluation

Five genomic loci within the DNMT1, DNMT3A and DNMT3B genes were assessed. Statistical significance (P = 0.030) was identified for DNMT1 SNP (A201G, rs2228612): six women within the control group were GG homozygous (variant), while this mutation was absent in the breast cancer group.

Conclusions

We conclude that women with the DNMT1 SNP (A201G, rs2228612) GG homozygous genotype (variant) have a lower risk of developing breast cancer compared to heterozygous or wildtype genotypes. To date, alterations within the DNMT1 gene have not been reported to be associated with cancer in the Caucasian population.
A protocol for a systematic review on the impact of unpublished studies and studies published in the gray literature in meta-analyses
Authors: Schmucker Christine , Bluemle Annette , Briel Matthias , Portalupi Susan , Lang Britta , Motschall Edith , Schwarzer Guido , Bassler Dirk , Mueller Katharina F , von Elm Erik , Meerpohl Joerg J
Published: May 2013

Background

Meta-analyses are particularly vulnerable to the effects of publication bias. Despite methodologists’ best efforts to locate all evidence for a given topic the most comprehensive searches are likely to miss unpublished studies and studies that are published in the gray literature only. If the results of the missing studies differ systematically from the published ones, a meta-analysis will be biased with an inaccurate assessment of the intervention’s effects.

As part of the OPEN project (http://www.open-project.eu) we will conduct a systematic review with the following objectives:

▪ To assess the impact of studies that are not published or published in the gray literature on pooled effect estimates in meta-analyses (quantitative measure).

▪ To assess whether the inclusion of unpublished studies or studies published in the gray literature leads to different conclusions in meta-analyses (qualitative measure).

Methods/Design

Inclusion criteria: Methodological research projects of a cohort of meta-analyses which compare the effect of the inclusion or exclusion of unpublished studies or studies published in the gray literature.

Literature search: To identify relevant research projects we will conduct electronic searches in Medline, Embase and The Cochrane Library; check reference lists; and contact experts.

Outcomes: 1) The extent to which the effect estimate in a meta-analyses changes with the inclusion or exclusion of studies that were not published or published in the gray literature; and 2) the extent to which the inclusion of unpublished studies impacts the meta-analyses’ conclusions.

Data collection: Information will be collected on the area of health care; the number of meta-analyses included in the methodological research project; the number of studies included in the meta-analyses; the number of study participants; the number and type of unpublished studies; studies published in the gray literature and published studies; the sources used to retrieve studies that are unpublished, published in the gray literature, or commercially published; and the validity of the methodological research project.

Data synthesis: Data synthesis will involve descriptive and statistical summaries of the findings of the included methodological research projects.

Discussion

Results are expected to be publicly available in the middle of 2013.