[Efficacy analysis of a novel dose-adjusting regimen for prolonged delayed injection allergen- specific immunotherapy for allergic rhinitis]

Objective: To investigate the efficacy and safety of a novel dose adjustment schedule based on subcutaneous immunotherapy (SCIT) after a 16 weeks delayed injection during the maintenance period. Methods: Sixty-eight patients with allergic rhinitis (AR) who received dust mite cluster SCIT and had interrupted treatment for more than 16 weeks during the maintenance period were recruited at Beijing TongRen Hospital, from July to September 2020. They were randomly divided into the novel schedule group (n=34) and the guideline recommended schedule group (n=34). In addition, 34 patients who received dust mite SCIT at the same period were selected as the continuous treatment group (n=34). When receiving treatment again after delayed injection, the novel schedule group was injected directly with the initial dose of maintenance period (10 000 SQ), and the guideline recommended schedule group started the dosage accumulation again from the lowest dose (10 SQ), while the continuous treatment group was injected according to the original schedule. Changes in the combined symptom and medication score (CSMS) from baseline after 3 years of SCIT were used as the primary efficacy evaluation index. Local and systemic adverse events were recorded to evaluate safety. SPSS 23.0 was used for statistical analysis. Results: At the end of 3 years, CSMS in all three groups decreased significantly from baseline, and there was no significant difference in the 3-year change value of CSMS from baseline between the novel schedule group and the guideline recommended schedule group (-1.0±0.3 vs -1.3±0.4, P=0.655). There was also no significant difference in the change of CSMS between the two dose-adjusted groups and the continuous treatment groups (-0.8±0.3 vs -1.3±0.3, P=0.156). No systemic adverse events occurred between the novel schedule group and the guideline recommended schedule group after restarting treatment, and there was no significant difference in frequency of adverse events (0.5% vs 0.5%, P=0.698). Conclusion: There is no significant difference in efficacy and safety between the novel dose adjustment schedule and the recommended dose adjustment schedule when SCIT interrupted injection for more than 16 weeks. Furthermore, SCIT discontinuation of injection for more than 16 weeks doesn't significantly impact on 3-year efficacy.

Prevalence of active HCV infection and genotypic distribution among the general population of district Mardan, Pakistan

Hepatitis C virus (HCV) is the serious global public health burden of liver disease. Approximately 170 million people in the world are infected with (HCV). In Pakistan, where the disease has high occurrence rate. The present study envisages an up-to-date prevalence of HCV and genotypic distribution in the general population of Mardan District, Khyber Pakhtunkhwa (KP), Pakistan. The blood samples from 6,538 individuals including 3,263 males and 3,275 females were analyzed for hepatitis C surface antigen by Immuno-chromatographic test (ICT), Enzyme-linked immunosorbent assay (ELISA), and reverse transcription-polymerase chain reaction (PCR). It was found that 396 (12.13%) out of 3263 individuals contained antibodies in their blood against HCV, while among the different age groups, the highest incidences of HCV antibodies were found in the 31-40 age group (11.01%). The ICT positive samples were further screened by nested PCR to determine the existence of active HCV-RNA. It was identified that 7.11% (3263) of the total population (6538) tested was positive, among which the 461 (14.07%) females possessed antibodies in their blood against HCV. Our data showed total HCV infection in the investigated population was 5.78%. Higher percentage of HCV prevalence was detected in males than females in the age group 31-40 and 41-50. To compare the prevalence of HCV genotypes age-wise in male and female genotype 3a was found most prevalent genotype followed by 1a, 2a and 3b, respectively.

Serological prevalence of hepatitis B virus (HBV) in Mardan district, Khyber Pakhtunkhwa, Pakistan

Hepatitis B virus infection is perilous among the five types of Hepatitis, as it remains clinically asymptomatic. The present study draws up-to-date prevalence of Hepatitis B virus (HBV) in the general population of Mardan, Khyber Pakhtunkhwa Pakistan. The blood samples from 4803 individuals including 2399 male and 2404 females were investigated. All the suspected samples were analyzed for hepatitis B surface antigen using Immuno-chromatographic test (ICT), Enzyme-linked immunosorbent assay (ELISA), and followed by Reverse transcription-polymerase chain reaction (RT-PCR). Results showed that 312 (13.00%) out of 2399 individuals contained antibodies in their blood against HBV, while among the different age groups, the highest incidences of HBV antibodies were found in the age of 21-30 groups (10.73%). Furthermore, the ICT positive samples were screened by nested polymerase chain reaction to detect the existence of active HBV-DNA. It was observed that 169 (7.04%) out of (2399) male of the total population (4803) tested was positive. On the other hand, the female 463 (19.25%) possessed antibodies in their blood against HBV. Accumulatively, our results showed a higher percentage of HBV prevalence in males than females in the age group 21-30 years. The total HCV infected in Mardan general population was recorded at 5.7% comprising both male and female.

Prunella vulgaris L protects glucocorticoids-induced osteogenesis inhibition in bone marrow mesenchymal stem cells through activating the Smad pathway

OBJECTIVE

To elucidate the role of Prunella vulgaris L (PVL) in protecting glucocorticoids (GC)-induced osteogenesis inhibition, thereafter, protecting the deterioration of osteoporosis (OP).

MATERIALS AND METHODS

Cell Counting Kit-8 (CCK-8) assay was conducted to assess the influence of PVL treatment on MSCs viability. Osteogenesis in MSCs was induced by Dexamethasone (DEX) stimulation. Regulatory effects of PVL on osteogenesis-related gene expressions, ALP activity, and mineralization ability in DEX-induced MSCs were determined. At last, protein levels of p-Smad1/5/9 and total-Smad1/5/9 influenced by DEX and PVL were measured by Western blot.

RESULTS

PVL treatment did not pose a time- or dose-dependent influence on MSCs viability. DEX induction in MSCs downregulated ALP, RUNX2, Bglap, and Osterix. ALP activity and mineralization in DEX-induced MSCs were suppressed. Downregulated osteogenesis-related genes decreased ALP activity and mineralization in MSCs undergoing DEX stimulation were partially reversed by PVL treatment. Moreover, the downregulated p-Smad1/5/9 level in DEX-induced MSCs was elevated by PVL treatment, while total-Smad1/5/9 was not affected.

CONCLUSIONS

PVL alleviated GC-induced suppression in MSCs osteogenesis by activating the Smad pathway, thereafter, protecting the deterioration of OP.

[Treatment of postprandial discomfort syndrome in the elderly: a multi-centered prospective randomized controlled clinical study]

Objective: To evaluate the efficacy and safety of Oryz-Aspergillus enzyme and pancreatin tablets (Combizym(®)) in the treatment of postprandial distress syndrome (PDS) in the elderly, compared with gastrointestinal motility drugs. Methods: A prospective randomized controlled trial was designed and registered in the China Clinical Trials Registry (ChiCTR-IPR-16008185). The elderly patients with PDS were randomly divided into three groups, including Mosapride group with Mosapride citrate tablets 5 mg 3 times per day for 2 weeks; Combizym(®) group with Combizym tablets 244 mg 3 times per day for 2 weeks; combined treatment group with both drugs and same doses for 2 weeks. The modified Nepean dyspepsia index (NDSI) score, discomfort intensity score and PDS score were calculated on patients before treatment, at the end of first and second week of treatment, as well as 4 weeks after treatment finished, respectively. Adverse effects were evaluated. Results: A total of 323 patients from 16 tertiary hospitals in China were enrolled in this study. Among them, 105 patients were in Mosapride group, 109 in Combizym(®) group and 109 in combined treatment group. There were 148 males (45.8%) and 175 females (54.2%) with median age 71.4±9.0 years (60-100 years). Baseline characteristics of three groups were comparable. After treatment, the NDSI scores in three groups all decreased significantly (P<0.001), while they were similar between groups (P>0.05). The discomfort intensity score and PDS score in three groups showed a significant reduction after treatment (P<0.001), especially in the combined treatment group. Compared with Mosapride group, the scores in Combizym(®) group decreased significantly after one or two weeks [discomfort intensity score: after one week, 4.0(2.5, 8.0) vs. 6.0(3.0, 10.0); after two weeks, 3.0(0.0, 5.0) vs. 4.0(2.0, 6.0); all P<0.05. PDS score: after one week, 6.0(3.0, 9.0) vs. 7.0(3.5, 10.5); after two weeks, 3.0(0.0, 5.0) vs. 4.0(2.0, 7.0); all P<0.05]. The efficacy rate in all patients after first week of treatment was over 15.0%. The efficacy rates after two weeks were 55.2%, 68.8% and 73.4% in Mosapride group, Combizym(®) group and combined treatment group, respectively. After two week treatment, the efficacy rates in Combizym(®) group (P=0.041) and combined group (P=0.006) were higher than that of Mosapride group. The recurrence rate of Mosapride group was 9.5%, which was significantly higher than that of Combizym(®) group (1.8%, P<0.05) and combined treatment group (1.8%, P<0.05). There were no serious adverse effects in the three groups. Conclusions: The efficacy of Oryz-Aspergillus enzyme and pancreatin tablets is comparable with that of Mosapride in elderly PDS patients, with fewer adverse effects and low recurrence rate. Combination regimen indicates better efficacy than that of Oryz-Aspergillus enzyme and pancreatin tablets or Mosapride alone.

Reduction of fibrillar strain-rate sensitivity in steroid-induced osteoporosis linked to changes in mineralized fibrillar nanostructure

As bone is used in a dynamic mechanical environment, understanding the structural origins of its time-dependent mechanical behaviour - and the alterations in metabolic bone disease - is of interest. However, at the scale of the mineralized fibrillar matrix (nanometre-level), the nature of the strain-rate dependent mechanics is incompletely understood. Here, we investigate the fibrillar- and mineral-deformation behaviour in a murine model of Cushing's syndrome, used to understand steroid induced osteoporosis, using synchrotron small- and wide-angle scattering/diffraction combined with in situ tensile testing at three strain rates ranging from 10-4 to 10-1 s-1. We find that the effective fibril- and mineral-modulus and fibrillar-reorientation show no significant increase with strain-rate in osteoporotic bone, but increase significantly in normal (wild-type) bone. By applying a fibril-lamellar two-level structural model of bone matrix deformation to fit the results, we obtain indications that altered collagen-mineral interactions at the nanoscale - along with altered fibrillar orientation distributions - may be the underlying reason for this altered strain-rate sensitivity. Our results suggest that an altered strain-rate sensitivity of the bone matrix in osteoporosis may be one of the contributing factors to reduced mechanical competence in such metabolic bone disorders, and that increasing this sensitivity may improve biomechanical performance.

125 Supplementing extra dietary DL-methionine mitigates effects of higher stocking density on growth performance, meat quality, and health status of broiler chicks

This study was to determine if 30% extra supplemental DL-methionine could improve growth performance, meat quality, and health status of broilers stocked at a high density. A total of 560 day-old male Cornish cockerel chicks were divided into 4 treatment groups: 2 stocking densities (2.9 and 3.8 kg/ft2) and 2 supplementations of DL-methionine (grower: 2.90 or 3.77 g/kg and finisher: 2.60 or 3.38 g/kg). Chicks were fed the same corn-soybean meal-based starter diet and then experimental diets (grower: 6.4 g SAA/kg, finisher: 5.9 g SAA/kg, n = 10 pens/treatment). Growth performance and mortality were recorded, and blood and tissue samples (3 chicks/pen) were collected at the end of each period. Data were analyzed by two-way ANOVA. High stocking density decreased (P &lt; 0.05) BW and (or) ADG of growers and finishers. Both high stocking density and methionine decreased (P &lt; 0.05) ADFI and the high methionine improved (P &lt; 0.05) feed use efficiency of chicks during the grower-finisher period. Neither treatment affected feather coverage, mortality, incidences of diseases, or dressing percentage. The high methionine improved (P &lt; 0.05) meat to bone ratio of thigh, and exerted mixed effects (P &lt; 0.05) on texture of breast and thigh. Dietary methionine and stocking density showed no major effects on tissue lipid profiles, but moderate effects (P &lt; 0.05) on plasma concentrations of total cholesterol and(or) triglycerides of chicks. Fatty acid profiles in the liver and breast of chicks were unaffected by either treatment. The two treatments enhanced (P &lt; 0.05) tibial maximum breaking strength (15–20%) and plasma alkaline phosphatase activity of growers. In conclusion, the high stocking density affected growth performance, meat quality, and health status of broilers. Supplementing 30% extra dietary methionine seemed to mitigate some of those effects. (Supported in part by Evonik Nutrition & Care GmbH, Germany)

Bone matrix development in steroid-induced osteoporosis is associated with a consistently reduced fibrillar stiffness linked to altered bone mineral quality

Glucocorticoid-induced osteoporosis (GIOP) is a major secondary form of osteoporosis, with the fracture risk significantly elevated - at similar levels of bone mineral density - in patients taking glucocorticoids compared with non-users. The adverse bone structural changes at multiple hierarchical levels in GIOP, and their mechanistic consequences leading to reduced load-bearing capacity, are not clearly understood. Here we combine experimental X-ray nanoscale mechanical imaging with analytical modelling of the bone matrix mechanics to determine mechanisms causing bone material quality deterioration during development of GIOP. In situ synchrotron small-angle X-ray diffraction combined with tensile testing was used to measure nanoscale deformation mechanisms in a murine model of GIOP, due to a corticotrophin-releasing hormone promoter mutation, at multiple ages (8-, 12-, 24- and 36 weeks), complemented by quantitative micro-computed tomography and backscattered electron imaging to determine mineral concentrations. We develop a two-level hierarchical model of the bone matrix (mineralized fibril and lamella) to predict fibrillar mechanical response as a function of architectural parameters of the mineralized matrix. The fibrillar elastic modulus of GIOP-bone is lower than healthy bone throughout development, and nearly constant in time, in contrast to the progressively increasing stiffness in healthy bone. The lower mineral platelet aspect ratio value for GIOP compared to healthy bone in the multiscale model can explain the fibrillar deformation. Consistent with this result, independent measurement of mineral platelet lengths from wide-angle X-ray diffraction finds a shorter mineral platelet length in GIOP. Our results show how lowered mineralization combined with altered mineral nanostructure in GIOP leads to lowered mechanical competence.

SIGNIFICANCE STATEMENT

Increased fragility in musculoskeletal disorders like osteoporosis are believed to arise due to alterations in bone structure at multiple length-scales from the organ down to the supramolecular-level, where collagen molecules and elongated mineral nanoparticles form stiff fibrils. However, the nature of these molecular-level alterations are not known. Here we used X-ray scattering to determine both how bone fibrils deform in secondary osteoporosis, as well as how the fibril orientation and mineral nanoparticle structure changes. We found that osteoporotic fibrils become less stiff both because the mineral nanoparticles became shorter and less efficient at transferring load from collagen, and because the fibrils are more randomly oriented. These results will help in the design of new composite musculoskeletal implants for bone repair.

Genome-wide Mapping of the Nucleosome Landscape by Micrococcal Nuclease and Chemical Mapping

Nucleosomes regulate the transcription output of the genome by occluding the underlying DNA sequences from DNA-binding proteins that must act on it. Knowledge of the precise locations of nucleosomes in the genome is thus essential towards understanding how transcription is regulated. Current nucleosome-mapping strategies involve digesting chromatin with nucleases or chemical cleavage followed by high-throughput sequencing. In this review, we compare the traditional micrococcal nuclease (MNase)-based approach with a chemical cleavage strategy, with discussion on the important insights each has uncovered about the role of nucleosomes in shaping transcriptional processes.

Insights into Nucleosome Organization in Mouse Embryonic Stem Cells through Chemical Mapping

Nucleosome organization influences gene activity by controlling DNA accessibility to transcription machinery. Here, we develop a chemical biology approach to determine mammalian nucleosome positions genome-wide. We uncovered surprising features of nucleosome organization in mouse embryonic stem cells. In contrast to the prevailing model, we observe that for nearly all mouse genes, a class of fragile nucleosomes occupies previously designated nucleosome-depleted regions around transcription start sites and transcription termination sites. We show that nucleosomes occupy DNA targets for a subset of DNA-binding proteins, including CCCTC-binding factor (CTCF) and pluripotency factors. Furthermore, we provide evidence that promoter-proximal nucleosomes, with the +1 nucleosome in particular, contribute to the pausing of RNA polymerase II. Lastly, we find a characteristic preference for nucleosomes at exon-intron junctions. Taken together, we establish an accurate method for defining the nucleosome landscape and provide a valuable resource for studying nucleosome-mediated gene regulation in mammalian cells.

Multiscale alterations in bone matrix quality increased fragility in steroid induced osteoporosis

A serious adverse clinical effect of glucocorticoid steroid treatment is secondary osteoporosis, enhancing fracture risk in bone. This rapid increase in bone fracture risk is largely independent of bone loss (quantity), and must therefore arise from degradation of the quality of the bone matrix at the micro- and nanoscale. However, we lack an understanding of both the specific alterations in bone quality n steroid-induced osteoporosis as well as the mechanistic effects of these changes. Here we demonstrate alterations in the nanostructural parameters of the mineralized fibrillar collagen matrix, which affect bone quality, and develop a model linking these to increased fracture risk in glucocorticoid induced osteoporosis. Using a mouse model with an N-ethyl-N-nitrosourea (ENU)-induced corticotrophin releasing hormone promoter mutation (Crh(-120/+)) that developed hypercorticosteronaemia and osteoporosis, we utilized in situ mechanical testing with small angle X-ray diffraction, synchrotron micro-computed tomography and quantitative backscattered electron imaging to link altered nano- and microscale deformation mechanisms in the bone matrix to abnormal macroscopic mechanics. We measure the deformation of the mineralized collagen fibrils, and the nano-mechanical parameters including effective fibril modulus and fibril to tissue strain ratio. A significant reduction (51%) of fibril modulus was found in Crh(-120/+) mice. We also find a much larger fibril strain/tissue strain ratio in Crh(-120/+) mice (~1.5) compared to the wild-type mice (~0.5), indicative of a lowered mechanical competence at the nanoscale. Synchrotron microCT show a disruption of intracortical architecture, possibly linked to osteocytic osteolysis. These findings provide a clear quantitative demonstration of how bone quality changes increase macroscopic fragility in secondary osteoporosis.

Selumetinib with and without erlotinib in KRAS mutant and KRAS wild-type advanced nonsmall-cell lung cancer

BACKGROUND

KRAS mutations in NSCLC are associated with a lack of response to epidermal growth factor receptor inhibitors. Selumetinib (AZD6244; ARRY-142886) is an oral selective MEK kinase inhibitor of the Ras/Raf/MEK/ERK pathway.

PATIENTS AND METHODS

Advanced nonsmall-cell lung cancer (NSCLC) patients failing one to two prior regimens underwent KRAS profiling. KRAS wild-type patients were randomized to erlotinib (150 mg daily) or a combination of selumetinib (150 mg daily) with erlotinib (100 mg daily). KRAS mutant patients were randomized to selumetinib (75 mg b.i.d.) or the combination. The primary end points were progression-free survival (PFS) for the KRAS wild-type cohort and objective response rate (ORR) for the KRAS mutant cohort. Biomarker studies of ERK phosphorylation and immune subsets were carried out.

RESULTS

From March 2010 to May 2013, 89 patients were screened; 41 KRAS mutant and 38 KRAS wild-type patients were enrolled. Median PFS in the KRAS wild-type arm was 2.4 months [95% confidence interval (CI) 1.3-3.7] for erlotinib alone and 2.1 months (95% CI 1.8-5.1) for the combination. The ORR in the KRAS mutant group was 0% (95% CI 0.0% to 33.6%) for selumetinib alone and 10% (95% CI 2.1% to 26.3%) for the combination. Combination therapy resulted in increased toxicities, requiring dose reductions (56%) and discontinuation (8%). Programmed cell death-1 expression on regulatory T cells (Tregs), Tim-3 on CD8+ T cells and Th17 levels were associated with PFS and overall survival in patients receiving selumetinib.

CONCLUSIONS

This study failed to show improvement in ORR or PFS with combination therapy of selumetinib and erlotinib over monotherapy in KRAS mutant and KRAS wild-type advanced NSCLC. The association of immune subsets and immune checkpoint receptor expression with selumetinib may warrant further studies.

Differential Nucleosome Occupancies across Oct4-Sox2 Binding Sites in Murine Embryonic Stem Cells

The binding sequence for any transcription factor can be found millions of times within a genome, yet only a small fraction of these sequences encode functional transcription factor binding sites. One of the reasons for this dichotomy is that many other factors, such as nucleosomes, compete for binding. To study how the competition between nucleosomes and transcription factors helps determine a functional transcription factor site from a predicted transcription factor site, we compared experimentally-generated in vitro nucleosome occupancy with in vivo nucleosome occupancy and transcription factor binding in murine embryonic stem cells. Using a solution hybridization enrichment technique, we generated a high-resolution nucleosome map from targeted regions of the genome containing predicted sites and functional sites of Oct4/Sox2 regulation. We found that at Pax6 and Nes, which are bivalently poised in stem cells, functional Oct4 and Sox2 sites show high amounts of in vivo nucleosome displacement compared to in vitro. Oct4 and Sox2, which are active, show no significant displacement of in vivo nucleosomes at functional sites, similar to nonfunctional Oct4/Sox2 binding. This study highlights a complex interplay between Oct4 and Sox2 transcription factors and nucleosomes among different target genes, which may result in distinct patterns of stem cell gene regulation.

CCR2 antagonism in patients with type 2 diabetes mellitus: a randomized, placebo-controlled study

AIMS

Macrophage recruitment through C-C motif chemokine receptor-2 (CCR2) into adipose tissue is believed to play a role in the development of insulin resistance and type 2 diabetes mellitus (T2DM). The objective of this Phase 2 proof-of-concept study was to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of JNJ-41443532, an orally bioavailable CCR2 antagonist, in patients with T2DM.

METHODS

This was a 4-week, double-blind, placebo-controlled, randomized, multicenter study. A total of 89 patients were randomized to receive either 250- or 1000-mg of JNJ-41443532 twice daily, 30-mg of pioglitazone once daily (reference arm), or placebo. The primary endpoint was change from baseline in 23-h weighted mean glucose (WMG); secondary endpoints included change from baseline in fasting plasma glucose (FPG), insulin resistance (Homeostatic Model Assessment [HOMA-IR]), insulin secretion (HOMA-%B) and body weight.

RESULTS

Absorption of JNJ-41443532 into the systemic circulation occurred at a median tmax of 2 h, and the mean t½ was approximately 8 h for both doses; plasma systemic exposures increased slightly more than dose-proportionally. After 4 weeks, reductions in 23-h WMG and FPG were observed in all treatment groups compared with placebo and were significantly lower for 250-mg JNJ-41443532 and pioglitazone. HOMA-IR was lower for all treatment groups, but significantly lower only for pioglitazone. Conversely, HOMA-%B was increased for all groups, but significantly increased only for 250-mg JNJ-41443532. All groups, including placebo, had decreased body weight over time. There were no clinically significant findings during routine safety assessments and the incidence of treatment-emergent adverse events was similar across all groups.

CONCLUSIONS

Administration of JNJ-41443532 resulted in modest improvement in glycaemic parameters compared with placebo, and was generally well tolerated in patients with T2DM.

Role of aluminum adjuvant in producing an allergic rhinitis animal model

This study evaluated different dosage forms of aluminum adjuvant in generating allergic rhinitis animal models. Forty female BALB/c mice were assigned to four groups, including three dosage forms of aluminum adjuvant [powder, gel, and hydrosolvent of aluminum hydroxide, Al(OH)3] mixed with ovalbumin to simulate the symptoms of allergic rhinitis and one control group. Although the aluminum adjuvants were in different dosage forms, the content was 5 mg after conversion in all groups. The fourth group was given normal saline instead as a control. Mice of the powder group displayed typical symptoms of allergic rhinitis. We also found discrete eosinophils in the nasal mucosa of mice from the hydrosolvent group; however, no eosinophils were found in the gel group. These two groups both displayed cytotoxic symptoms and foreign body granuloma. Aluminum adjuvant used in producing animal models can induce foreign body granuloma and other untoward reactions, which are associated with the dosage level and form.

A locally convoluted cluster model for nucleosome positioning signals in chemical map

Nucleosome is the fundamental packing unit of DNA in eukaryotic cells, and its positioning plays a critical role in regulation of gene expression and chromosome functions. Using a recently developed chemical mapping method, nucleosomes can be potentially mapped with an unprecedented single-base-pair resolution. Existence of overlapping nucleosomes due to cell mixture or cell dynamics, however, causes convolution of nucleosome positioning signals. In this paper, we introduce a locally convoluted cluster model and a maximum likelihood deconvolution approach, and illustrate the effectiveness of this approach in quantification of the nucleosome positional signal in the chemical mapping data.

Archaeal nucleosome positioning in vivo and in vitro is directed by primary sequence motifs

Background

Histone wrapping of DNA into nucleosomes almost certainly evolved in the Archaea, and predates Eukaryotes. In Eukaryotes, nucleosome positioning plays a central role in regulating gene expression and is directed by primary sequence motifs that together form a nucleosome positioning code. The experiments reported were undertaken to determine if archaeal histone assembly conforms to the nucleosome positioning code.

Results

Eukaryotic nucleosome positioning is favored and directed by phased helical repeats of AA/TT/AT/TA and CC/GG/CG/GC dinucleotides, and disfavored by longer AT-rich oligonucleotides. Deep sequencing of genomic DNA protected from micrococcal nuclease digestion by assembly into archaeal nucleosomes has established that archaeal nucleosome assembly is also directed and positioned by these sequence motifs, both in vivo in Methanothermobacter thermautotrophicus and Thermococcus kodakarensis and in vitro in reaction mixtures containing only one purified archaeal histone and genomic DNA. Archaeal nucleosomes assembled at the same locations in vivo and in vitro, with much reduced assembly immediately upstream of open reading frames and throughout the ribosomal rDNA operons. Providing further support for a common positioning code, archaeal histones assembled into nucleosomes on eukaryotic DNA and eukaryotic histones into nucleosomes on archaeal DNA at the same locations. T. kodakarensis has two histones, designated HTkA and HTkB, and strains with either but not both histones deleted grow normally but do exhibit transcriptome differences. Comparisons of the archaeal nucleosome profiles in the intergenic regions immediately upstream of genes that exhibited increased or decreased transcription in the absence of HTkA or HTkB revealed substantial differences but no consistent pattern of changes that would correlate directly with archaeal nucleosome positioning inhibiting or stimulating transcription.

Conclusions

The results obtained establish that an archaeal histone and a genome sequence together are sufficient to determine where archaeal nucleosomes preferentially assemble and where they avoid assembly. We confirm that the same nucleosome positioning code operates in Archaea as in Eukaryotes and presumably therefore evolved with the histone-fold mechanism of DNA binding and compaction early in the archaeal lineage, before the divergence of Eukaryotes.

Efficacy and safety of canagliflozin in subjects with type 2 diabetes and chronic kidney disease

AIMS

Canagliflozin is a sodium glucose co-transporter 2 inhibitor in development for treatment of type 2 diabetes mellitus (T2DM). This study evaluated the efficacy and safety of canagliflozin in subjects with T2DM and stage 3 chronic kidney disease [CKD; estimated glomerular filtration rate (eGFR) ≥30 and <50 ml/min/1.73 m(2)].

METHODS

In this randomized, double-blind, placebo-controlled, phase 3 trial, subjects (N = 269) received canagliflozin 100 or 300 mg or placebo daily. The primary efficacy endpoint was change from baseline in HbA1c at week 26. Prespecified secondary endpoints were change in fasting plasma glucose (FPG) and proportion of subjects reaching HbA1c <7.0%. Safety was assessed based on adverse event (AE) reports; renal safety parameters (e.g. eGFR, blood urea nitrogen and albumin/creatinine ratio) were also evaluated.

RESULTS

Both canagliflozin 100 and 300 mg reduced HbA1c from baseline compared with placebo at week 26 (-0.33, -0.44 and -0.03%; p < 0.05). Numerical reductions in FPG and higher proportions of subjects reaching HbA1c < 7.0% were observed with canagliflozin 100 and 300 mg versus placebo (27.3, 32.6 and 17.2%). Overall AE rates were similar for canagliflozin 100 and 300 mg and placebo (78.9, 74.2 and 74.4%). Slightly higher rates of urinary tract infections and AEs related to osmotic diuresis and reduced intravascular volume were observed with canagliflozin 300 mg compared with other groups. Transient changes in renal function parameters that trended towards baseline over 26 weeks were observed with canagliflozin.

CONCLUSION

Canagliflozin improved glycaemic control and was generally well tolerated in subjects with T2DM and Stage 3 CKD.

High-resolution nucleosome mapping of targeted regions using BAC-based enrichment

We report a target enrichment method to map nucleosomes of large genomes at unprecedented coverage and resolution by deeply sequencing locus-specific mononucleosomal DNA enriched via hybridization with bacterial artificial chromosomes. We achieved ∼10 000-fold enrichment of specific loci, which enabled sequencing nucleosomes at up to ∼500-fold higher coverage than has been reported in a mammalian genome. We demonstrate the advantages of generating high-sequencing coverage for mapping the center of discrete nucleosomes, and we show the use of the method by mapping nucleosomes during T cell differentiation using nuclei from effector T-cells differentiated from clonal, isogenic, naïve, primary murine CD4 and CD8 T lymphocytes. The analysis reveals that discrete nucleosomes exhibit cell type-specific occupancy and positioning depending on differentiation status and transcription. This method is widely applicable to mapping many features of chromatin and discerning its landscape in large genomes at unprecedented resolution.

A map of nucleosome positions in yeast at base-pair resolution

The exact positions of nucleosomes along genomic DNA can influence many aspects of chromosome function, yet existing methods for mapping nucleosomes do not provide the necessary single base pair accuracy to determine these positions. Here we develop and apply a new approach for direct mapping of nucleosome centers based on chemical modification of engineered histones. The resulting map locates nucleosome positions genome-wide in unprecedented detail and accuracy. It reveals novel aspects of the in vivo nucleosome organization that are linked to transcription factor binding, RNA polymerase pausing, and the higher order structure of the chromatin fiber.

Effects of JNJ-38431055, a novel GPR119 receptor agonist, in randomized, double-blind, placebo-controlled studies in subjects with type 2 diabetes

AIM

G-protein coupled receptor agonists are currently under investigation for their potential utility in patients with type 2 diabetes mellitus (T2DM). The objective was to determine the pharmacokinetics, pharmacodynamics, safety and tolerability of GPR119 agonist, JNJ-38431055 in T2DM subjects.

METHODS

This was a randomized, double-blind, placebo- and positive-controled, single-dose cross-over study and a randomized, double-blind, placebo-controled multiple-dose parallel design study. The study was conducted at 4 US research centres. Two different experiments involving 25 and 32 different subjects were performed in male and female subjects, aged 25-60 years, mean body mass index between 22 and 39.9 kg/m2 who had T2DM diagnosed 6 months to 10 years before screening. JNJ-38431055 (100 and 500 mg) or sitagliptin (100 mg) as a single-dose or JNJ-38431055 (500 mg) once daily for 14 consecutive days were tested. Effects on stimulated plasma glucose, insulin, C-peptide and incretin concentrations were pre-specified outcomes.

RESULTS

JNJ-38431055 was well tolerated and not associated with hypoglycaemia. Plasma systemic exposure of JNJ-38431055 increased as the dose increased, was approximately two-fold greater after multiple-dose administration, and attained steady-state after approximately 8 days. Compared with placebo, single-dose administration of oral JNJ-38431055 decreased glucose excursion during an oral glucose tolerance test, but multiple-dose administration did not alter 24-h weighted mean glucose. Multiple dosing of JNJ-38431055 increased post-meal total glucagon-like peptide 1 and gastric insulinotropic peptide concentrations compared to baseline.

CONCLUSIONS

These studies provide evidence of limited glucose lowering and incretin activity for JNJ-38431055 in subjects with T2DM.

Effect of asthma, aeroallergen category, and gender on the psychological status of patients with allergic rhinitis

BACKGROUND

Despite increasing evidence for an association between allergy and psychological disorders in patients with allergic rhinitis (AR), the relationship between comorbid AR and asthma is not clear. The objective of this study was to investigate the effect of concomitant asthma, gender, and sensitization to a particular aeroallergen category on the psychological status of AR patients.

METHODS

We analyzed 524 AR patients (311 males/213 females) aged 16 to 60 years using the Symptom Checklist-90 (SCL-90) and found that 34.2% had persistent AR and 65.8% intermittent AR. Overall, 61 patients (11.6%) had concomitant asthma.

RESULTS

The SCL-90 scores of AR patients were significantly higher for the somatization, obsessive-compulsive, hostility, and psychoticism dimensions than those of the healthy controls. In contrast, the SCL-90 scores for persistent AR and intermittent AR patients were significantly different. Concomitant asthma significantly impacted theAR individuals' SCL-90 dimension scores for the obsessive-compulsive, interpersonal sensitivity, depression, and paranoid ideation subscales. Gender and sensitization to a particular aeroallergen category did not affect the SCL-90 scores of AR patients individually, but led to significant differences in SCL-90 scores for the phobic anxiety and psychoticism subscales when considered in combination.

CONCLUSION

Our results suggest that comorbid asthma exerts an independent main effect on the psychological status of AR patients.

A chemical approach to mapping nucleosomes at base pair resolution in yeast

Most eukaryotic DNA exists in DNA-protein complexes known as nucleosomes. The exact locations of nucleosomes along the genome play a critical role in chromosome functions and gene regulation. However, the current methods for nucleosome mapping do not provide the necessary accuracy to identify the precise nucleosome locations. Here we describe a new experimental approach that directly maps nucleosome center locations in vivo genome-wide at single base pair resolution.

Effects of alpha-lipoic acid supplementation on antioxidative ability and performance of sows and nursing piglets

The current study was carried out to determine the effects of alpha-lipoic acid (LA) supplementation during late-gestation and lactation on antioxidative ability and performance of sows and their nursing piglets. A total of 160 multiparous sows were randomly allocated to four treatments with 40 replicates per treatment according to parity number and backfat (BF) thickness. Sows were fed 1 of 4 diets from day 85 of gestation to day 21 of lactation. Diets were control without LA; 400 ppm LA supplementation; 600 ppm LA supplementation; and 800 ppm LA supplementation. BF thickness of sows was determined on day 85 and 110 of gestation and days 1 and 21 of lactation. Piglet bodyweight was measured at birth, days 7, 14 and 21. Blood samples were obtained from the sows, and average daily feed intake (ADFI) of the sows during lactation was recorded. There were no differences in BF thickness or ADFI among treatment groups. Dietary LA supplementation resulted in a decrease in blood urea nitrogen (p < 0.01) concentration at days 110 of gestation. Dietary 800 ppm LA increased serum glutathione peroxidase (GSH-Px) activity (p < 0.05) and reduced maleic dialdehyde levels (p < 0.01) of sows compared with the control diet at days 21 of lactation. Alpha-lipoic acid supplementation increased the birthweight and weaning weight of piglets (p < 0.01) compared with the control group. Weight gains of piglets from sows fed the 800 ppm LA diets were greater (p < 0.01) between days 7 and 14 compared with piglets from control sows. Weight gains of piglets from sows fed the LA-supplemented diets were greater between days 14 and 21 (p < 0.05) and between days 1 and 21 (p < 0.01) compared with piglets from control-fed sows. In conclusion, the results indicate that antioxidant LA was effective in enhancing antioxidant enzymes activity and improving the performance of sows and their nursing piglets.