Genomic and proteomic expression analysis of Leishmania promastigote and amastigote life stages: the Leishmania genome is constitutively expressed

Leishmania are protozoan parasites that cause a wide spectrum of clinical diseases in humans and are a major public health risk in several countries. Leishmania life cycle consists of an extracellular flagellated promastigote stage within the midgut of a sandfly vector, and a morphological distinct intracellular amastigote stage within macrophages of a mammalian host. This study reports the use of DNA oligonucleotide genome microarrays representing 8160 genes to analyze the mRNA expression profiles of L. major promastigotes and lesion derived amastigotes. Over 94% of the genes were expressed in both life stages. Advanced statistical analysis identified a surprisingly low degree of differential mRNA expression: 1.4% of the total genes in amastigotes and 1.5% in promastigotes. These microarray results demonstrate that the L. major genome is essentially constitutively expressed in both life stages and suggest that Leishmania is constitutively adapted for survival and replication in either the sandfly vector or macrophage host utilizing an appropriate set of genes for each vastly different environment. Quantitative proteomics, using the isotope coded affinity tag (ICAT) technology and mass spectrometry, was used to identify L. infantum promastigote and axenic amastigote differentially expressed proteins. Of the 91 distinct proteins identified, 8% were differentially expressed in the amastigote stage, 20% were differentially expressed in the promastigote stage, and the remaining 72% were considered constitutively expressed. The differential expression was validated by the identification of previously reported stage specific proteins and identified several amastigote and promastigote novel stage specific proteins.     

Effects of applied DC electric field on ligament fibroblast migration and wound healing

Applied electric fields (static and pulsing) are widely used in orthopedic practices to treat nonunions and spine fusions and have been shown to improve ligament healing in vivo. Few studies, however, have addressed the effect of electric fields (EFs) on ligament fibroblast migration and biosynthesis. In the current study, we applied static and pulsing direct current (DC) EFs to calf anterior cruciate ligament (ACL) fibroblasts. ACL fibroblasts demonstrated enhanced migration speed and perpendicular alignment to the applied EFs. The motility of ligament fibroblasts was further modulated on type I collagen. In addition, type I collagen expression increased in ACL fibroblasts after exposure to pulsing EFs. In vitro wound-healing studies showed inhibitory effects of static EFs, which were alleviated with a pulsing EF. Our results demonstrate that applied EFs augment ACL fibroblast migration and biosynthesis and provide potential mechanisms by which EFs may be used for enhancing ligament healing and repair.     

Development of Stabilizing Formulations of a Trivalent Inactivated Poliovirus Vaccine in a Dried State for Delivery in the Nanopatch™ Microprojection Array

The worldwide switch to inactivated polio vaccines (IPVs) is a key component of the overall strategy to achieve and maintain global polio eradication. To this end, new IPV vaccine delivery systems may enhance patient convenience and compliance. In this work, we examine Nanopatch? (a solid, polymer microprojection array) which offers potential advantages over standard needle/syringe administration including intradermal delivery and reduced antigen doses. Using trivalent IPV (tIPV) and a purpose-built evaporative dry-down system, candidate tIPV formulations were developed to stabilize tIPV during the drying process and on storage. Identifying conditions to minimize tIPV potency losses during rehydration and potency testing was a critical first step. Various classes and types of pharmaceutical excipients (～50 total) were then evaluated to mitigate potency losses (measured through D-antigen ELISAs for IPV1, IPV2, and IPV3) during drying and storage. Various concentrations and combinations of stabilizing additives were optimized in terms of tIPV potency retention, and 2 candidate tIPV formulations containing cyclodextrin and a reducing agent (e.g., glutathione), maintained ≥80% D-antigen potency during drying and subsequent storage for 4 weeks at 4°C, and ≥60% potency for 3 weeks at room temperature with the majority of losses occurring within the first day of storage.     

National estimates of severe sepsis in United States emergency departments

OBJECTIVE: The emergency department (ED) often serves as the first site for the recognition and treatment of patients with suspected severe sepsis. However, few evaluations of the national epidemiology and distribution of severe sepsis in the ED exist. We sought to determine national estimates of the number, timing, ED length of stay, and case distribution of patients presenting to the ED with suspected severe sepsis. DESIGN: Analysis of 2001-2004 ED data from the National Hospital Ambulatory Medical Care Survey. SETTING: National multistage probability sample of United States ED data. PATIENTS: Adult (age, >or=18 yrs) patients with suspected severe sepsis, defined as the concurrent presence of an infec-tion (ED International Classification of Diseases, 9th Revision; ICD-9) diagnosis of infection, or a triage temperature <96.8 degrees F or >or=100.4 degrees F) and organ dysfunction (ED ICD-9) diagnosis of organ dysfunction, intubation, or a triage systolic blood pressure 6 hrs in the ED. Of suspected severe sepsis patients, 20.6% presented to a low-volume ED (相似文献   

The placement of osseointegrated dental implants in a patient with type IV B osteogenesis imperfecta: a 9-year follow-up

Osteogenesis imperfecta (OI) is a rare autosomal dominant connective tissue and metabolic disorder. Typically, patients with OI exhibit bone fragility, with the sclera, joints, skin, and tooth dentin being affected to varying degrees. Despite existing classifications, there is an extreme phenotypic variation within this population, and at times the mild forms of OI may be difficult to diagnose. Comprehensive management of the severe types of OI involves aggressive physical and surgical orthopaedic treatment to improve muscle structure and joint mobility. For those patients with associated dentinogenesis imperfecta (DI), early and definitive management can help prevent excessive tooth wear and sensitivity. A case of a late diagnosis of type IV OI with DI successfully treated with implant-supported dentures is reported. To date, 9 years after implant surgery and prosthetic loading, the patient continues to be clinically and radiographically normal.     

An OxPLORE Initiative Evaluating Children’s Surgery Resources Worldwide: A Cross-sectional Implementation of the OReCS Document

World Journal of Surgery - The Global Initiative for Children's Surgery (GICS) group produced the Optimal Resources for Children’s Surgery (OReCS) document in 2019, listing standards of...     

Dendritic nanostructured FeS2-based high stability and capacity Li-ion cathodes

Here we show that dendritic architectures are attractive as the basis of hierarchically structured battery electrodes. Dendritically structured FeS₂, synthesized via simple thermal sulfidation of electrodeposited dendritic α-Fe, was formed into an electrode and cycled vs. lithium. The reversible capacities of the dendritic FeS₂ cathode were 560 mA h g⁻¹ at 0.5C and 533 mA h g⁻¹ at 1.0C after 50 cycles over 0.7–3.0 V. Over 0.7–2.4 V, where the electrode is more stable, the reversible capacities are 348 mA h g⁻¹ at 0.2C and 179 mA h g⁻¹ at 1.0C after 150 cycles. The good cycling performance and high specific capacities of the dendritic FeS₂ cathodes are attributed to the ability of a dendritic structure to provide good ion and electron conducting pathways, and a large surface area. Importantly, the dendritic structure appears capable of accommodating volume changes imposed by the lithiation and delithiation process. The presence of a Li_2−xFeS₂ phase is indicated for the first time by high-resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) electron energy loss spectroscopy (EELS). We suspect this phase is what enables electrochemical cycling to possess high reversibility over 0.7–2.4 V.

High performance dendritically structured FeS₂ cathodes are systemically studied. The dendritic structure is resistant to volume changes during cycling, increasing cyclability. The presence of Li_2–xFeS₂, which also enhances cyclability, is confirmed.     

Mutation in sodium-calcium exchanger 1 (NCX1) causes cardiac fibrillation in zebrafish

Cardiac fibrillation, a form of cardiac arrhythmia, is the most common cause of embolic stroke and death associated with heart failure. The molecular mechanisms underlying cardiac fibrillation are largely unknown. Here we report a zebrafish model for cardiac fibrillation. The hearts of zebrafish tremblor (tre) mutants exhibit chaotic movements and fail to develop synchronized contractions. Calcium imaging showed that normal calcium transients are absent in tre cardiomyocytes, and molecular cloning of the tre mutation revealed that the tre locus encodes the zebrafish cardiac-specific sodium-calcium exchanger (NCX) 1, NCX1h. Forced expression of NCX1h or other calcium-handling molecules restored synchronized heartbeats in tre mutant embryos in a dosage-dependent manner, demonstrating the critical role of calcium homeostasis in maintaining embryonic cardiac function. By creating mosaic zebrafish embryos, we showed that sporadic NCX1h-null cells were not sufficient to disrupt normal cardiac function, but clustered wild-type cardiomyocytes contract in unison in tre mutant hearts. These data signify the essential role of calcium homeostasis and NCX1h in establishing rhythmic contraction in the embryonic zebrafish heart.