Safety, immunogenicity, and efficacy of a recombinantly produced Plasmodium falciparum circumsporozoite protein-hepatitis B surface antigen subunit vaccine

Twenty malaria-naive volunteers received a recombinant Plasmodium falciparum malaria vaccine (RTS,S) containing 19 NANP repeats and the carboxy terminus (amino acids 210-398) of the circumsporozoite (CS) antigen coexpressed in yeast with hepatitis B surface antigen. Ten received vaccine adjuvanted with alum, and 10 received vaccine adjuvanted with alum plus 3-deacylated monophosphoryl lipid A (MPL). Both formulations were well tolerated and immunogenic. MPL enhanced CS antibody levels (measured by ELISA, immunofluorescence, and inhibition of sporozoite invasion assays). After sporozoite challenge, 6 of 6 in the alum group and 6 of 8 in the alum-MPL group developed patent malaria. Protected subjects had higher levels of CS antibody titers on day of challenge than did nonprotected subjects. After immunization, 1 protected subject had increased cytotoxic T lymphocyte activity against CS and recall of memory T cell responses to RTS,S and selected CS.

Regulation of groE expression in Bacillus subtilis: the involvement of the sigma A-like promoter and the roles of the inverted repeat sequence (CIRCE)

To study the regulatory mechanism controlling the heat-inducible expression of Bacillus subtilis groE, two regulatory elements, the sigma A-like promoter and the inverted repeat (IR [CIRCE]) in the control region, were characterized. The groE promoter was shown to be transcribed by the major RNA polymerase under both heat shock and non-heat shock conditions. The IR was found to have two functions. (i) It ensures the fast turnover of the groE transcript, and (ii) it serves as an operator. This IR acts as a negative heat shock regulatory element, since deletion of this sequence resulted in high-level expression of groE even at 37 degrees C. Although this IR is present in the 5' untranslated region of the groE transcript, groE transcripts under heat shock and non-heat shock conditions showed similar in vivo half-lives of 5 min. This rapid turnover at 37 degrees C requires the presence of the IR. Without the IR, the groE transcript showed a longer half-life of 17 min. Increasing the distance between the groE transcription start site and the IR systematically by inserting nucleotide sequences from 5 to 21 bp in length resulted in a gradual abolition of the negative regulatory effect mediated by the IR. This effect was not due to a significant change in transcript stability or the transcription start site and is consistent with the model that this IR serves as an operator.

Isolation and characterization of Bacillus subtilis groE regulatory mutants: evidence for orf39 in the dnaK operon as a repressor gene in regulating the expression of both groE and dnaK

An inverted repeat sequence known as CIRCE (controlling inverted repeat of chaperone expression) in the Bacillus subtilis groE operon has been suggested to function as an operator. To identify the regulatory gene directly or indirectly involved in CIRCE-mediated heat-inducible groE expression, B. subtilis WBG2, carrying an integrated groE-bgaB transcription fusion in the amyE locus, was mutagenized. Dark blue colonies formed at 37 degrees C represent mutants which constitutively produce BgaB (a thermostable beta-galactosidase) at high levels. Seven mutants (WBG101 to WBG107) were selected for further characterization. They all overproduced BgaB, GroEL, and DnaK simultaneously at 37 degrees C. These mutants could be restored to normal by introducing a plasmid carrying a functional copy of orf39, the first gene in the B. subtilis dnaK operon. Genomic sequencing of these mutants demonstrated that they all carried a single mutation in orf39. These mutations can be divided into three groups: (i) Gly-307 to Asp, (ii) Ser-122 to Phe, and (iii) Gly-63 to Glu. By using a binary vector system in E. coli, production of ORF39 was found to negatively regulate the expression of groE-bgaB in a CIRCE-specific manner. Under the heat shock condition, the negative regulation mediated by ORF39 was abolished. Mobility shift of the CIRCE-containing probe was also observed with the crude extract prepared from the E. coli strain that overproduced ORF39. Therefore, ORF39 is the negative regulatory factor which regulates both groE and dnaK expression in B. subtilis. It is likely to function as a CIRCE-specific repressor.

Measurement of the depth of maximum of extensive air showers above 10{18} eV

We describe the measurement of the depth of maximum, X{max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10;{18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{-21}{+35}) g/cm{2}/decade below 10{18.24+/-0.05} eV, and (24+/-3) g/cm{2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.

BMP activity is required for tooth development from the lamina to bud stage

Several Bmp genes are expressed in the developing mouse tooth germ from the initiation to the late-differentiation stages, and play pivotal roles in multiple steps of tooth development. In this study, we investigated the requirement of BMP activity in early tooth development by transgenic overexpression of the extracellular BMP antagonist Noggin. We show that overexpression of Noggin in the dental epithelium at the tooth initiation stage arrests tooth development at the lamina/early-bud stage. This phenotype is coupled with a significantly reduced level of cell proliferation rate and a down-regulation of Cyclin-D1 expression, specifically in the dental epithelium. Despite unaltered expression of genes known to be implicated in early tooth development in the dental mesenchyme and dental epithelium of transgenic embryos, the expression of Pitx2, a molecular marker for the dental epithelium, became down-regulated, suggesting the loss of odontogenic fate in the transgenic dental epithelium. Our results reveal a novel role for BMP signaling in the progression of tooth development from the lamina stage to the bud stage by regulating cell proliferation and by maintaining odontogenic fate of the dental epithelium.

Cloning and characterization of human guanine deaminase. Purification and partial amino acid sequence of the mouse protein

Mouse erythrocyte guanine deaminase has been purified to homogeneity. The native enzyme was dimeric, being comprised of two identical subunits of approximately 50,000 Da. The protein sequence was obtained from five cyanogen bromide cleavage products giving sequences ranging from 12 to 25 amino acids in length and corresponding to 99 residues. Basic Local Alignment Search Tool (BLAST) analysis of expressed sequence databases enabled the retrieval of a human expressed sequence tag cDNA clone highly homologous to one of the mouse peptide sequences. The presumed coding region of this clone was used to screen a human kidney cDNA library and secondarily to polymerase chain reaction-amplify the full-length coding sequence of the human brain cDNA corresponding to an open reading frame of 1365 nucleotides and encoding a protein of 51,040 Da. Comparison of the mouse peptide sequences with the inferred human protein sequence revealed 88 of 99 residues to be identical. The human coding sequence of the putative enzyme was subcloned into the bacterial expression vector pMAL-c2, expressed, purified, and characterized as having guanine deaminase activity with a Km for guanine of 9.5 +/- 1.7 microM. The protein shares a 9-residue motif with other aminohydrolases and amidohydrolases (PGX[VI]DXH[TVI]H) that has been shown to be ligated with heavy metal ions, commonly zinc. The purified recombinant guanine deaminase was found to contain approximately 1 atom of zinc per 51-kDa monomer.

A convenient method for the synthesis of DNA-recognizing polyamides in solution

A convenient method for the synthesis of polyamides containing N-methylpyrrole (Py) and N-methylimidazole (Im) in solution has been developed. Most of the building blocks have been prepared by a haloform reaction in a simple way that column chromatography can be avoided. By use of the DCC/HOBT coupling reaction, the building blocks prepared have been effectively connected to construct a variety of subchains and polyamides without employing amino protection and deprotection. By use of the present method, an eight-ring polyamide, PyPyPyPygammaPyImImPybetaDp (gamma is gamma-aminobutyric acid, beta is beta-alanine, Dp is N, N-dimethylpropyldiamine), has been synthesized by the coupling of two four-ring subchains in one step.

A survey of outcomes and management of patients post fragility fractures in China

We found that the fragility hip and vertebral fractures caused excess mortality rates in this Chinese female population, which was unexpectedly lower than those in western countries and other Asian countries. This was the first nationwide survey relating to post-fracture outcomes conducted among Chinese population in Mainland China.

INTRODUCTION

This study aimed to investigate the mortality, self-care ability, diagnosis, and medication treatment of osteoporosis following fragility hip and vertebral fractures through a nationwide survey among female patients aged over 50 in Mainland China.

METHODS

This was a multicenter, retrospective cohort study based on medical chart review and patient questionnaire. Female patients aged 50 or older admitted for low-trauma hip or vertebral fractures and discharged from Jan 1, 2008 to Dec 31, 2012 were followed.

RESULTS

Total of 1151 subjects of hip fracture and 842 subjects of vertebral fracture were included. The mean age was 73.4 ± 10.0, and the median of duration from index fracture to interview was 2.6 years. The overall 1-year, 2-year, 3-year, 4-year, and 5-year cumulative mortality rates were 3.5, 7.0, 11.2, 13.1, and 16.9 %, respectively. The first year mortality rates in hip (3.8 %, 95% CI 3.3-4.4 %) and vertebral fracture (3.1 %, 95% CI 2.5-3.7 %) were significantly higher than that in the general population (1.6 %). Impaired self-care ability was observed in 33.2, 40.6, and 23.8 % of overall, hip fracture, and vertebral fracture group, respectively. The overall diagnosis rate of osteoporosis was 56.8 %, and bone mineral density (BMD) measurement had never been conducted in 42.0 % among these women. After the index fracture, 69.6 % of them received supplements and/or anti-osteoporotic medications, among which 39.6 % only received calcium with/without vitamin D supplementation.

CONCLUSIONS

The osteoporotic hip and vertebral fractures caused excess mortality rates in this population of Mainland China. The current diagnosis and medical treatment following the fragility fractures is still insufficient in Mainland China.

Measurement of the proton-air cross section at √s=57 TeV with the Pierre Auger Observatory

We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505±22(stat)(-36)(+28)(syst)] mb is found.

Decrease in heart mitochondrial creatine kinase activity due to oxygen free radicals

This study was undertaken to examine the effects of oxygen free radicals on mitochondrial creatine kinase activity in rat heart. Xanthine plus xanthine oxidase (superoxide anion radical generating system) reduced mitochondrial creatine kinase activity both in a dose- and a time-dependent manner. Superoxide dismutase showed a protective effect on depression in creatine kinase activity due to xanthine plus xanthine oxidase. Hydrogen peroxide inhibited creatine kinase activity in a dose-dependent manner, this inhibition was protected by the addition of catalase. In order to understand the detailed mechanisms by which oxygen free radicals inhibit mitochondrial creatine kinase activity, the effects of oxygen free radicals on mitochondrial sulfhydryl groups were examined. Mitochondrial sulfhydryl groups contents were decreased by xanthine plus xanthine oxidase or hydrogen peroxide; this depression in sulfhydryl groups contents was prevented by the addition of superoxide dismutase or catalase. N-Ethylmaleimide (sulfhydryl group reagent) expressed inhibitory effects on the creatine kinase activity both in a dose- and a time-dependent manner; dithiothreitol or cysteine (sulfhydryl group reductant) showed protective effects on the creatine kinase activity depression induced by N-ethylmaleimide. Dithiothreitol or cysteine also blocked the depression of mitochondrial creatine kinase activity caused by xanthine plus xanthine oxidase or hydrogen peroxide. These results lead us to conclude that oxygen free radicals may inhibit mitochondrial creatine kinase activity by modifying sulfhydryl groups in the enzyme protein.

High efficiency chlorine removal from polyvinyl chloride (PVC) pyrolysis with a gas-liquid fluidized bed reactor

In this research a gas-liquid fluidized bed reactor was developed for removing chlorine (Cl) from polyvinyl chloride (PVC) to favor its pyrolysis treatment. In order to efficiently remove Cl within a limited time before extensive generation of hydrocarbon products, the gas-liquid fluidized bed reactor was running at 280-320 °C, where hot N2 was used as fluidizing gas to fluidize the molten polymer, letting the molten polymer contact well with N2 to release Cl in form of HCl. Experimental results showed that dechlorination efficiency is mainly temperature dependent and 300 °C is a proper reaction temperature for efficient dechlorination within a limited time duration and for prevention of extensive pyrolysis; under this temperature 99.5% of Cl removal efficiency can be obtained within reaction time around 1 min after melting is completed as the flow rate of N2 gas was set around 0.47-0.85 Nm(3) kg(-1) for the molten PVC. Larger N2 flow rate and additives in PVC would enhance HCl release but did not change the final dechlorination efficiency; and excessive N2 flow rate should be avoided for prevention of polymer entrainment. HCl is emitted from PVC granules or scraps at the mean time they started to melt and the melting stage should be taken into consideration when design the gas-liquid fluidized bed reactor for dechlorination.

Co-transplantation of bone marrow stromal cells transduced with IL-7 gene enhances immune reconstitution after allogeneic bone marrow transplantation in mice

Allogeneic bone marrow transplantation (allo-BMT) is followed by a period of profound immune deficiency, which results in significant susceptibility to infections and limits the extensive application of this approach in clinic. Here, we transduced human interleukin-7 (IL-7) gene into donor-derived bone marrow stromal cells (MSCs) using adenovirus vector, and transplanted this gene-engineered MSCs (MSC-IL-7) into lethally irradiated C57BL/6 mice to investigate their effects on immune reconstitution following allo-BMT. Recipient mice receiving MSC-IL-7 cells plus T-cell-depleted bone marrow cells of BALB/c mice showed a significant increase in thymopoiesis and homeostatic expansion of peripheral T lymphocytes. Furthermore, injection of MSC-IL-7 cells following allo-BMT protected the host from the lethality caused by acute graft-versus-host disease (GVHD) and prevented the occurrence of GVHD induced by transplanted T cells. Thus, the use of MSC-IL-7 cells may be therapeutically useful for enhancing immune reconstitution without aggravating GVHD in allo-BMT mice.

Polymorphism of HMGA1 is associated with increased risk of type 2 diabetes among Chinese individuals

AIMS/HYPOTHESIS

Variants of the high-mobility group A1 (HMGA1) gene have been shown to be associated with insulin resistance and type 2 diabetes in individuals of European origin. We aimed to determine whether this locus confers significant susceptibility to type 2 diabetes in the Han Chinese population, and thus cross-race susceptibility to type 2 diabetes.

METHODS

Polymorphisms in HMGA1 were identified by direct sequencing of genomic DNA derived from 192 Chinese participants (96 patients with type 2 diabetes and 96 controls). We then genotyped the common variant IVS5-13insC (c.136-14_136-13insC) in two other independent cohorts, including a total of 2,533 cases and 2,643 ethnically matched controls.

RESULTS

We confirmed the association of the HMGA1 variant IVS5-13insC (c.136-14_136-13insC) with type 2 diabetes with an OR of 1.34 (95% CI 1.15, 1.56, p = 0.0002 under a dominant model, and 95% CI 1.16, 1.55, p = 0.0002 under an additive model) in the Han Chinese population, corresponding to a population attributable risk fraction of 5.0%.

CONCLUSIONS/INTERPRETATION

HMGA1 is an important susceptibility locus that confers a high cross-race risk of the development of type 2 diabetes.

Nontraditional risk factors for cardiovascular disease and visceral adiposity index among different body size phenotypes

BACKGROUND AND AIMS

Increased cardiovascular disease and mortality risk in metabolically healthy obese (MHO) individuals remain highly controversial. Several studies suggested risk while others do not. The traditional cardiovascular risk factors may be insufficient to demonstrate the complete range of metabolic abnormalities in MHO individuals. Hence, we aimed to compare the prevalence of elevated lipoprotein (a), apolipoprotein B, and uric acid (UA) levels, apolipoprotein B/apolipoprotein A1 ratio, and visceral adiposity index (VAI) scores, and low apolipoprotein A1 levels among 6 body size phenotypes (normal weight with and without metabolic abnormalities, overweight with and without metabolic abnormalities, and obese with or without metabolic abnormalities).

METHODS AND RESULTS

We conducted a cross-sectional analysis of 7765 Chinese adults using data from the nationwide China Health and Nutrition Survey 2009. MHO persons had intermediate prevalence of elevated apolipoprotein B and UA levels, apolipoprotein B/apolipoprotein A1 ratio and VAI scores, and low apolipoprotein A1 levels between metabolically healthy normal-weight (MHNW) and metabolically abnormal obese individuals (P < 0.001 for all comparisons). Elevated apolipoprotein B and UA concentrations, apolipoprotein B/apolipoprotein A1 ratio, and VAI scores were all strongly associated with the MHO phenotype (all P < 0.01).

CONCLUSIONS

Prevalence of elevated apolipoprotein B and UA levels, apolipoprotein B/apolipoprotein A1 ratio and VAI scores, and low levels of apolipoprotein A1 was higher among MHO persons than among MHNW individuals. The elevated levels of the nontraditional risk factors and VAI scores in MHO persons could contribute to the increased cardiovascular disease risk observed in long-term studies.

Mechanoresponsive Properties of the Periodontal Ligament

The periodontal ligament (PDL) functions as an enthesis, a connective tissue attachment that dissipates strains created by mechanical loading. Entheses are mechanoresponsive structures that rapidly adapt to changes in their mechanical loading; here we asked which features of the PDL are sensitive to such in vivo loading. We evaluated the PDL in 4 physiologically relevant mechanical environments, focusing on mitotic activity, cell density, collagen content, osteogenic protein expression, and organization of the tissue. In addition to examining PDLs that supported teeth under masticatory loading and eruptive forces, 2 additional mechanical conditions were created and analyzed: hypoloading and experimental tooth movement. Collectively, these data revealed that the adult PDL is a remarkably quiescent tissue and that only when it is subjected to increased loads—such as those associated with mastication, eruption, and orthodontic tooth movement—does the tissue increase its rate of cell proliferation and collagen production. These data have relevance in clinical scenarios where PDL acclimatization can be exploited to optimize tooth movement.

Mdm2 Promotes Odontoblast-like Differentiation by Ubiquitinating Dlx3 and p53

Dentin is an important structural component of the tooth. Odontoblast differentiation is an essential biological process that guarantees normal dentin formation, which is precisely regulated by various proteins. Murine double minute 2 (Mdm2) is an E3 ubiquitin ligase, and it plays a pivotal role in the differentiation of different cell types, such as osteoblasts and myoblasts. However, whether Mdm2 plays a role in odontoblast differentiation remains unknown. Here, we investigated the spatiotemporal expression of Mdm2 by immunostaining and found that Mdm2 was highly expressed in the odontoblasts and slightly in the dental papilla cells of mouse incisors and molars. Gene knockdown and overexpression experiments verified that Mdm2 promoted the odontoblast-like differentiation of mouse dental papilla cells (mDPCs). Intranuclear colocalization and physical interaction between Mdm2 and distal-less 3 (Dlx3), a transcription factor important for odontoblast differentiation, was found during the odontoblast-like differentiation of mDPCs by double immunofluorescence and immunoprecipitation. Mdm2 was proved to monoubiquitinate Dlx3, which enhanced the expression of Dlx3 target gene Dspp. In addition, p53, the canonical substrate of Mdm2, was validated to be also ubiquitinated but degraded by Mdm2 during the odontoblast-like differentiation of mDPCs. Gene knockdown experiments confirmed that p53 inhibited the odontoblast-like differentiation of mDPCs. p53 and Mdm2 double knockdown partially rescued the reduced odontoblast-like differentiation by knockdown of Mdm2 alone. Taken together, our study revealed that Mdm2 promoted the odontoblast-like differentiation of mDPCs by ubiquitinating both Dlx3 and p53. On one hand, the monoubiquitination of Dlx3 by Mdm2 led to upregulation of Dspp, which is a marker of the odontoblast differentiation. On the other hand, ubiquitination of p53 by Mdm2 resulted in its degradation, which eliminated the inhibitory effect of p53 on the odontoblast-like differentiation of mDPCs.

RGS12 Represses Oral Cancer via the Phosphorylation and SUMOylation of PTEN

Oral squamous cell carcinoma (OSCC) is the most common head and neck cancer characterized by aggressive local invasion and metastasis. The pathogenesis of OSCC is mainly due to the accumulation of genetic alterations in epithelial cells, but the underlying mechanism for its development remains unclear. Here, we found that the expression level of regulator of G protein signaling 12 (RGS12) was significantly reduced in human OSCC. To understand the role and mechanism of RGS12 in OSCC, we generated a novel RGS12 global knockout (CMV^Cre/+; RGS12^fl/fl) mouse model by crossing RGS12^fl/fl mice with CMV-Cre transgenic mice and then further induced the mice to develop OSCC by using 4-nitroquinoline 1-oxide (4NQO). Deletion of RGS12 exhibited aggressive OSCC in the tongue compared with the control RGS12^fl/fl mice. Knockdown of RGS12 in OSCC cells significantly increased cell proliferation and migration. Mechanistically, we found that RGS12 associated with phosphatase and tension homolog (PTEN) via the PDZ domain to upregulate the phosphorylation and SUMOylation of PTEN and then correspondingly inactivated the AKT/mTOR signaling pathway. To test the potential therapeutic effect of RGS12 on OSCC, we overexpressed RGS12 in OSCC cells and found a significant inhibition of cancer cell proliferation and migration. Moreover, subcutaneous inoculation of RGS12-overexpressed OSCC cells in NOD scid mice showed a significant reduction in tumor formation. Our findings reveal that RGS12 is an essential tumor suppressor and highlights RGS12 as a potential therapeutic target and prognostic biomarker of OSCC.