Mammalian spermatozoa become fully motile and fertile during transit through the luminal fluid of the epididymis. At least 200 proteins are present in the epididymal lumen, but the potential roles of these luminal proteins in male fertility are unknown. Investigation of the function of these proteins will elucidate the mechanism of sperm maturation, and also provide new drug targets for male contraception. We cloned RNase9 from a human epididymis cDNA library for characterization and analysis of its functions.
It was predicted that human RNase9 gene was located on chromosome 14q11.2 and encoded a 205 amino acids protein with a signal peptide of 26 amino acids at the N-terminus. The protein had eight conserved cysteine residues characteristic of the RNase A family members and several potential post-translational modification sites.
At the transcriptional level, RNase9 was expressed in a wide variety of tissues, and the expression was higher in men than in boys. RNase9 was localized to the post-equatorial region of the sperms' head. Immunofluorescence staining showed that RNase9 protein was present mostly in the epithelium of the epididymal tubule. Recombinant RNase9 had no ribonuclease activity. In addition, RNase9 had no detectable effect on sperm motility and fertilization as demonstrated by blocking spermatozoa with anti-RNase9 polyclonal serum.
RNase9 is expressed in a wide variety of tissues. It is located on the post-equatorial region of the sperm head and the epithelium of epididymal tubule. Although RNase9 belongs to the RNase A family, it has no ribonuclease activity.
Guanosine at position 26 in eukaryotic tRNAs is usually modified to N2 , N2 -dimethylguanosine (m22G26). In Saccharomyces cerevisiae , this reaction is catalysed by the TRM1 encoded tRNA (m22G26)dimethyltransferase. As a prerequisite for future studies, the yeast TRM1 gene was expressed in Escherichia coli and the His-tagged Trm1 protein (rTrm1p) was extensively purified. rTrm1p catalysed both the mono- and dimethylation of G26 in vivo in Escherichia coli tRNA and in vitro in yeast trm1 mutant tRNA. The TRM1 gene from two independent wild-type yeast strains differed at 14 base positions causing two amino acid exchanges . Exchange of the original Ser467 for Leu caused a complete loss of enzyme activity in vitro against trm1 yeast tRNA. Comparatively short N- or C-terminal deletions from the 570 amino acid long Trm1 polypeptide decreased or eliminated the enzyme activity, as did some point mutations within these regions. This indicated that the protein is not a two domain peptide with the enzyme activity localised to one of the domains, but rather that both ends of the polypeptide seem to interact to influence the conformation of those parts that make up the RNA-binding site and/or the active site of the enzyme.
The pathogenesis of obesity remains incompletely understood. Drosophila have conserved neuroendocrine and digestion systems with human and become an excellent system for studying energy homeostasis. Here, we reported a novel obesity Drosophila model, in which expression of human protein, synphilin-1 (SP1), in neurons fosters positive energy balance.
SUBJECTS AND METHODS
To further understand the actions of SP1 in energy balance control, the upstream activation sequence UAS/GAL4 system was used to generate human SP1 transgenic Drosophila. We characterized a human SP1 transgenic Drosophila by assessing SP1 expression, fat lipid deposition, food intake and fly locomotor activity to determine the major behavioral changes and their consequences in the development of the obesity-like phenotype.
Overexpression of SP1 in neurons, but not peripheral cells, increased the body weight of flies compared with that of non-transgenic controls. SP1 increased food intake but did not affect locomotor activity. SP1 increased the levels of triacylglycerol, and the size of fat body cells and lipid droplets, indicating that SP1 increased lipid-fat disposition. Survival studies showed that SP1 transgenic flies were more resistant to food deprivation. SP1 regulated lipin gene expression that may participate in SP1-induced fat deposition and starvation resistance.
These studies demonstrate that SP1 expression affects energy homeostasis in ways that enhance positive energy balance and provide a useful obesity model for future pathogenesis and therapeutic studies.
Synphilin-1; fat disposition; transgenic Drosophila; lipin
We sought to determine the effect of hydroxychloroquine therapy on the levels proinflammatory/prothrombotic markers and disease activity scores in patients with systemic lupus erythematosus (SLE) in a multiethnic, multi-center cohort (LUMINA).
Plasma/serum samples from SLE patients (n=35) were evaluated at baseline and after hydroxychloroquine treatment. Disease activity was assessed using SLAM-R scores. Interferon (IFN)-α2, interleukin (IL)-1β, IL-6, IL-8, inducible protein (IP)-10, monocyte chemotactic protein-1, tumor necrosis factor (TNF)-α and soluble CD40 ligand (sCD40L) levels were determined by a multiplex immunoassay. Anticardiolipin antibodies were evaluated using ELISA assays. Thirty-two frequency-matched plasma/serum samples from healthy donors were used as controls.
Levels of IL-6, IP-10, sCD40L, IFN-α and TNF-α were significantly elevated in SLE patients versus controls. There was a positive but moderate correlation between SLAM-R scores at baseline and levels of IFN-α (p=0.0546). Hydroxychloroquine therapy resulted in a significant decrease in SLAM-R scores (p=0.0157), and the decrease in SLAM-R after hydroxychloroquine therapy strongly correlated with decreases in IFN-α (p=0.0087).
Hydroxychloroquine therapy resulted in significant clinical improvement in SLE patients, which strongly correlated with reductions in IFN-α levels. This indicates an important role for the inhibition of endogenous TLR activation in the action of hydroxychloroquine in SLE and provides additional evidence for the importance of type I interferons in the pathogenesis of SLE. This study underscores the use of hydroxychloroquine in the treatment of SLE.
Lupus; hydroxychloroquine; biomarkers of inflammation; biomarkers of thrombosis
The bone-forming metastases of prostate cancer result from complex stromal–epithelial interactions within the tumour microenvironment. Autocrine–paracrine signalling pathways between prostate cancer epithelial cells, osteoblasts, and osteoclasts stimulate aberrant bone remodelling, and the activity of these three cell populations can be quantitatively measured using prostate-specific antigen (PSA), bone-specific alkaline phosphatase (BAP) and urine N-telopeptide (uNTx), respectively. The purpose of the present study was to test the hypothesis that serial measurements of BAP and uNTx during therapy would facilitate monitoring of disease activity and predict the overall survival (OS) in patients with metastatic prostate cancer receiving therapy.
Radionuclide bone scan, PSA, BAP, and uNTx data were retrospectively analysed from three clinical trials in patients with metastatic prostate cancer conducted at our institution. Qualitative changes in bone scans and quantitative changes in PSA, BAP, and uNTx concentrations during therapy were correlated with OS.
Baseline levels of BAP, but not PSA, were prognostic for OS in both androgen-dependent and castrate-resistant disease. A reduction in PSA, BAP, uNTx, or BAP/uNTx on therapy was predictive of improved OS in both patient groups. Conversely, an increase in PSA, or BAP on therapy was predictive of worse OS in both patient groups. Baseline number of lesions and response on bone scan during therapy were neither prognostic nor predictive of OS in either patient group.
These observations support the concept that serial measurements of bone turnover metabolites during therapy function as clinically informative predictive biomarkers in patients with advanced prostate cancer and skeletal metastases. PSA measurements and bone scans remain essential to monitor the overall disease activity and determine the anatomic distribution of skeletal metastases.
prostate cancer; bone; predictive biomarkers; metastases
Spin-triplet superconductivity in Sr2RuO4 has attracted enormous interest. Like other unconventional superconductors, superconductivity in Sr2RuO4 is in close proximity to magnetic instability. Undoped Sr2RuO4 exhibits incommensurate antiferromagnetic (AFM) fluctuations, which can evolve into static, short-range AFM order via Ti doping. Moreover, weak ferromagnetic (FM) coupling in Sr2RuO4 has also been suggested by NMR/neutron scattering experiments and studies on Ca2−xSrxRuO4 and Sr2−yLayRuO4, implying orbital dependent magnetism. We report bulk static, short-range FM order in Sr2RuO4 triggered by <2% Co doping, showing superconductivity in Sr2RuO4 is much closer to FM instability than previously reported in Ca2−xSrxRuO4. We also find Mn doping can effectively establish incommensurate AFM order, with TN ~ 50 K for 3% Mn doping. These new results place Sr2RuO4 in a unique situation where superconductivity lies directly on the borderline of two distinct magnetic states, highlighting the important role of competing magnetic fluctuations in determining superconducting properties of Sr2RuO4.
LIM homeobox domain 6 (LHX6) is a putative transcriptional regulator that controls the differentiation and development of neural and lymphoid cells. However, the function of LHX6 in cancer development remains largely unclear. Recently, we found that LHX6 is hypermethylated in lung cancer. In this study, we analysed its epigenetic regulation, biological functions, and related molecular mechanisms in lung cancer. Methylation status was evaluated by methylation-specific PCR and bisulfite genomic sequencing. LHX6 mRNA levels were measured in relation to the methylation status. The effects of LHX6 expression on tumourigenesis were studied in vitro and in vivo. LHX6 was readily expressed in normal lung tissues without methylation, but was downregulated or silenced in lung cancer cell lines and tissues with hypermethylation status. Treatment of lung cancer cells with the demethylating agent 5-aza-2′-deoxycytidine restored LHX6 expression. Moreover, LHX6 hypermethylation was detected in 56% (52/93) of primary lung cancers compared with none (0/20) of the tested normal lung tissues. In lung cancer cell lines 95D and H358, forced expression of LHX6 suppressed cell viability, colony formation, and migration, induced apoptosis and G1/S arrest, and inhibited their tumorigenicity in nude mice. On the other hand, knockdown of LHX6 expression by RNA interference increased cell proliferation and inhibited apoptosis and cell cycle arrest. These effects were associated with upregulation of p21 and p53, and downregulation of Bcl-2, cyclinD1, c-myc, CD44, and MMP7. In conclusion, our results suggest that LHX6 is a putative tumour suppressor gene with epigenetic silencing in lung cancer.
LHX6; DNA methylation; tumour suppressor; lung cancer; epigenetics
The inherent resistance of tumors to DNA damage often limits the efficacy of chemotherapy. The aim of this work is to explore the potential mechanism for development of chemoresistance in gastric cancer. Our data revealed that AKT1 mRNA and protein expression were induced by doxorubicin (a chemotherapeutic agent); the doxorubicin-induced AKT1 expression and activation increased the binding of NF-kappaB on Notch1 DNA promoter and then promoted the Notch1 transcription and expression; enhanced expression of Notch1 further upregulated PTEN expression through CBF-1 binding to PTEN DNA promoter; and inhibition of AKT1 expression and activity sensitized the gastric cancer cell to doxorubicin treatment in cultured gastric cancer cell lines and xenograft nude mice gastric cancer model. Furthermore, our data demonstrated that both Notch1 and PTEN were absent or minimally expressed in gastric cancer tissue but abundant in paired normal gastric mucosa, and the expression of Notch1 correlated with that of PTEN. Together, these novel results suggested that a novel AKT1/NF-kappaB/Notch1/PTEN axis has an important role in the development of chemoresistance in gastric cancer. Notch1 has an anti-cancer role in gastric cancer.
AKT1; NF-kappaB; Notch-1; PTEN; gastric cancer
We report a high-quality draft sequence of the genome of the horse (Equus caballus). The genome is relatively repetitive, but has little segmental duplication. Chromosomes appear to have undergone few historical rearrangements – 48% of equine chromosomes show conserved synteny to a single human chromosome. Equine chromosome 11 is shown to have an evolutionary novel centromere devoid of centromeric satellite DNA, suggesting that centromeric function may arise prior to satellite repeat accumulation. Linkage disequilibrium, showing the influences of early domestication of large herds of female horses, is intermediate in length between dog and human, and there is long-range haplotype sharing among breeds.
To date, no standardized presentation format is taught to emergency medicine (EM) residents during patient handoffs to consulting or admitting physicians. The Situation-Background-Assessment-Recommendation (SBAR) is a common format that provides a consistent framework to communicate pertinent information.
The objective of this study was to describe and evaluate the feasibility of using SBAR to teach interphysician communication skills to first-year EM residents to use during patient handoffs.
An educational study was designed as part of a pilot curriculum to teach first-year EM residents handoff communication skills. A standardized SBAR reporting format was taught during a 1-hour didactic intervention. All residents were evaluated using pretest/posttest simulated cases using a 17-item SBAR checklist initially, and then within 4 months to assess retention of the tool. A survey was distributed to determine resident perceptions of the training and potential clinical utility.
There was a statistically significant improvement from the resident scores on the pretest/posttest of the first case (P = .001), but there was no difference between posttest of the first case and pretest of the second case (P = .34), suggesting retention of the material. There was a statistically significant improvement from the pretest and posttest scores on the second case (P = .001). The survey yielded good reliability for both sessions (Cronbach alpha = 0.87 and 0.89, respectively), demonstrating statistically significant increases for the perceived quality of training, presentation comfort level, and the use of SBAR (P = .001).
SBAR was acceptable to first-year EM residents, with improvements in both the ability to apply SBAR to simulated case presentations and retention at a follow-up session. This format was feasible to use as a training method and was well received by our resident physicians. Future research will be useful in examining the general applicability of the SBAR model for interphysician communications in the clinical environment and residency training programs.
The exact influence of statins on gefitinib resistance in human non-small cell lung cancer (NSCLC) cells with KRAS mutation alone or KRAS/PIK3CA and KRAS/PTEN comutations remains unclear. This work found that transfection of mutant KRAS plasmids significantly suppressed the gefitinib cytotoxicity in Calu3 cells (wild-type KRAS). Gefitinib disrupted the Kras/PI3K and Kras/Raf complexes in Calu3 cells, whereas not in Calu3 KRAS mutant cells. These trends were corresponding to the expression of pAKT and pERK in gefitinib treatment. Atorvastatin (1 μM) plus gefitinib treatment inhibited proliferation, promoted cell apoptosis, and reduced the AKT activity in KRAS mutant NSCLC cells compared with gefitinib alone. Atorvastatin (5 μM) further enhanced the gefitinib cytotoxicity through concomitant inhibition of AKT and ERK activity. Atorvastatin could interrupt Kras/PI3K and Kras/Raf complexes, leading to suppression of AKT and ERK activity. Similar results were also obtained in comutant KRAS/PTEN or KRAS/PIK3CA NSCLC cells. Furthermore, mevalonate administration reversed the effects of atorvastatin on the Kras/Raf and Kras/PI3K complexes, as well as AKT and ERK activity in both A549 and Calu1 cells. The in vivo results were similar to those obtained in vitro. Therefore, mutant KRAS-mediated gefitinib insensitivity is mainly derived from failure to disrupt the Kras/Raf and Kras/PI3K complexes in KRAS mutant NSCLC cells. Atorvastatin overcomes gefitinib resistance in KRAS mutant NSCLC cells irrespective of PIK3CA and PTEN statuses through inhibition of HMG-CoA reductase-dependent disruption of the Kras/Raf and Kras/PI3K complexes.
gefitinib; atorvastatin; mutant KRAS; NSCLC
Many natural compounds derived from plants or microbes show promising potential for anticancer treatment, but few have been found to target energy-relevant regulators. In this study, we report that neoalbaconol (NA), a novel small-molecular compound isolated from the fungus, Albatrellus confluens, could target 3-phosphoinositide-dependent protein kinase 1 (PDK1) and inhibit its downstream phosphoinositide-3 kinase (PI3-K)/Akt-hexokinase 2 (HK2) pathway, which eventually resulted in energy depletion. By targeting PDK1, NA reduced the consumption of glucose and ATP generation, activated autophagy and caused apoptotic and necroptotic death of cancer cells through independent pathway. Necroptosis was remarkably induced, which was confirmed by several necroptosis-specific markers: the activation of autophagy, presence of necrotic morphology, increase of receptor-interacting protein 1 (RIP1)/RIP3 colocalization and interaction and rescued by necroptosis inhibitor necrostatin-1. The possibility that Akt overexpression reversed the NA-induced energy crisis confirmed the importance of the PDK1-Akt-energy pathway in NA-mediated cell death. Moreover, NA shows the capability to inhibit PI3-K/Akt signaling and suppress tumor growth in the nasopharyngeal carcinoma (NPC) nude mouse model. These results supported the feasibility of NA in anticancer treatments.
neoalbaconol; PDK1; PI3-K/Akt; energy depletion; cancer cell death
Accumulating evidence indicates that epithelial-to-mesenchymal transition (EMT) might be a key event for cancer progression. The upregulation of Snail1, one of the most extensively studied EMT regulators, has been implicated in cancer metastasis, but the underlying mechanisms remain unclear. This study aims to identify that Snail1 targets regulating EMT-associated cancer cell migration. Human lung carcinoma A549 cells were treated with transforming growth factor beta 1 (TGF-β1), and EMT-associated phenotypic and functional alterations were monitored. TGF-β1 induced typical EMT-like morphological changes, ‘cadherin switching' and cell migration in A549 cells. TGF-β1 stimulation induced rapid and persistent upregulation of Snail1. Moreover, Snail1 upregulation was required for EMT-associated cell migration. Several metastasis suppressors with putative Snail1-binding sites in their promoters were dramatically repressed in A549 cells during TGF-β1-induced EMT. Gain- and loss-of Snail1 function experiments demonstrated that scavenger receptor class A member 5 (SCARA5) was negatively regulated by Snail1. Importantly, SCARA5 downregulation was essential for EMT-induced migration in A549 cells. The chromatin immunoprecipitation assay revealed that Snail1 could bind to the E-box elements in SCARA5 promoter, implying that SCARA5 is a direct Snail1 target modulating cancer cell mobility during EMT. In addition, we showed that DNA methyltransferase 1 was physically associated with Snail1 to silence SCARA5 expression with an unidentified DNA methylation-independent mechanism, suggesting the complexity of Snail1-mediated epigenetic regulation. Collectively, our data demonstrated that EMT-regulator Snail1 suppresses the expression of SCARA5 to promote cancer progression, highlighting the possibility to target Snail1 and SCARA5 for cancer treatment.
Snail1; TGF-β1; EMT; migration; SCARA5; lung cancer
The Au/DyMnO3/Nb:SrTiO3/Au stack was demonstrated to be not only a high performance memristor but also a good memcapacitor. The switching time is below 10 ns, the retention is longer than 105 s, and the change ratio of resistance (or capacitance) is larger than 100 over the 108 switching cycles. Moreover, this stack has a broad range of intermediate states that are tunable by the operating voltages. It is indicated that the memory effects originate from the Nb:SrTiO3/Au junction where the barrier profile is electrically modulated. The serial connected Au/DyMnO3/Nb:SrTiO3 stack behaves as a high nonlinear resistor paralleling with a capacitor, which raises the capacitance change ratio and enhances the memory stability of the device.
The changes of photosynthetic parameters, water use efficiency (WUE), fatty acid composition, chlorophyll (Chl) content, malondialdehyde (MDA) content, ATPase and acid phosphatase activities, fluoride (F) content, and leaf anatomical structure of two tea cultivars, “Pingyangtezao” (PY) and “Fudingdabai” (FD), after F treatments were investigated. The results show that net photosynthetic rate (Pn), stomatal conductance (gs), and transpiration rate (E) significantly decreased in both cultivars after 0.3 mM F treatment, but FD had higher Pn, gs, and WUE and lower E than PY. Chl content in PY significantly decreased after 0.2 and 0.3 mM F treatments, while no significant changes were observed in FD. The proportions of shorter chain and saturated fatty acids increased and those of longer chain and unsaturated fatty acids decreased in both cultivars under F treatments. The contents of MDA increased after F treatments but were higher in PY than in FD. In addition, F treatments decreased the activities of ATPase and acid phosphatase and increased F content in both cultivars; however, compared with PY, FD showed higher enzymatic activities and lower F content in roots and leaves. Leaf anatomical structure in FD indicated that cells in leaf midrib region were less injured by F than in PY.
Sublethal ischemic preconditioning (IPC) is a powerful inducer of ischemic brain
tolerance. However, its underlying mechanisms are still not well understood. In
this study, we chose four different IPC paradigms, namely 5 min (5 min
duration), 5×5 min (5 min duration, 2 episodes, 15-min interval), 5×5×5 min (5
min duration, 3 episodes, 15-min intervals), and 15 min (15 min duration), and
demonstrated that three episodes of 5 min IPC activated autophagy to the
greatest extent 24 h after IPC, as evidenced by Beclin expression and LC3-I/II
conversion. Autophagic activation was mediated by the tuberous sclerosis type 1
(TSC1)-mTor signal pathway as IPC increased TSC1 but decreased mTor
phosphorylation. Terminal deoxynucleotidyl transferase dUTP nick end labeling
(TUNEL) and hematoxylin and eosin staining confirmed that IPC protected against
cerebral ischemic/reperfusion (I/R) injury. Critically, 3-methyladenine, an
inhibitor of autophagy, abolished the neuroprotection of IPC and, by contrast,
rapamycin, an autophagy inducer, potentiated it. Cleaved caspase-3 expression,
neurological scores, and infarct volume in different groups further confirmed
the protection of IPC against I/R injury. Taken together, our data indicate that
autophagy activation might underlie the protection of IPC against ischemic
injury by inhibiting apoptosis.
Ischemic preconditioning; Autophagy; Apoptosis; Focal cerebral ischemic reperfusion
Activation of Akt and increased expression of integrin β3 are the two most important changes that have been linked to the attainment of metastatic potential by prostate cancer cells. However, a direct link between Akt activity and inside-out activation of integrin β3 in mediating prostate cancer cell metastatic properties is not established.
Using functional and biochemical approaches, we examined the role of Akt1 in the affinity modulation of integrin β3 in prostate cancer cells.
Although expression of murine TRAMP and human PC3 cells with constitutively active Akt1 (CA-Akt1) enhanced their affinity for integrin αvβ3 specific ligands and motility on various extracellular matrix proteins, the reverse was observed with the expression of dominant-negative Akt1 (DN-Akt1). Although enhanced motility and transendothelial migration of CA-Akt1-expressing cells were blunted by co-expression with DN-integrin β3 or upon pre-treatment with integrin β3-blocking antibodies (LM 609), impaired motility and transendothelial migration of DN-Akt1-expressing cells were rescued by pre-treatment of prostate cancer cells with integrin β3-activating antibodies, AP7.4.
Our data is the first to demonstrate a link between Akt1 activity and affinity modulation of integrin β3 in the regulation of prostate cancer cell motility, transendothelial migration and chemotaxis to metastatic stimuli.
prostate cancer; chemotaxis; invasion; bone matrix; Akt1; integrin αvβ3
The use of general anaesthetics in young children and infants has raised concerns regarding the adverse effects of these drugs on brain development. Sevoflurane might have harmful effects on the developing brain; however, these effects have not been well investigated.
Postnatal day 7 (P7) Sprague–Dawley rats were continuously exposed to 2.3% sevoflurane for 6 h. We used the Fox battery test and Morris water maze (MWM) to examine subsequent neurobehavioural performance. Cleaved caspase-3 and neuronal nitric oxide synthase (nNOS) were quantified by immunoblotting, and the Nissl staining was used to observe the histopathological changes in the hippocampus.
A single 6 h sevoflurane exposure at P7 rats resulted in increased cleaved caspase-3 expression and decreased nNOS levels in the hippocampus, and induced the loss of pyramidal neurones in the CA1 and CA3 subfields of the hippocampus at P7–8. These changes were accompanied by temporal retardation of sensorimotor reflexes. However, neither the Fox battery test at P1–21 nor the MWM test at P28–32 showed differences between the air- and sevoflurane-treated groups.
Although early exposure to sevoflurane increases activated caspase-3 expression and neuronal loss and decreases nNOS in the neonatal hippocampus, it does not affect subsequent neurobehavioural performances in juvenile rats.
anaesthetic, sevoflurane; caspase 3; hippocampus; memory; neuronal nitric oxide synthase; sevoflurane
Hepatic oval cells (HOCs) are recognized as facultative liver progenitor cells that
play a role in liver regeneration after acute liver injury. Here, we investigated the
in vitro proliferation and differentiation characteristics of
HOCs in order to explore their potential capacity for intrahepatic transplantation.
Clusters or scattered HOCs were detected in the portal area and interlobular bile
duct in the liver of rats subjected to the modified 2-acetylaminofluorene and partial
hepatectomy method. Isolated HOCs were positive for c-kit and CD90 staining (99.8%
and 88.8%, respectively), and negative for CD34 staining (3.6%) as shown by
immunostaining and flow cytometric analysis. In addition, HOCs could be
differentiated into hepatocytes and bile duct epithelial cells after leukemia
inhibitory factor deprivation. A two-cuff technique was used for orthotopic liver
transplantation, and HOCs were subsequently transplanted into recipients. Biochemical
indicators of liver function were assessed 4 weeks after transplantation. HOC
transplantation significantly prolonged the median survival time and improved the
liver function of rats receiving HOCs compared to controls (P=0.003, Student
t-test). Administration of HOCs to rats also receiving liver
transplantation significantly reduced acute allograft rejection compared to control
liver transplant rats 3 weeks following transplantation (rejection activity index
score: control=6.3±0.9; HOC=3.5±1.5; P=0.005). These results indicate that HOCs may
be useful in therapeutic liver regeneration after orthotopic liver
Hepatic oval cells; Proliferation; Differentiation; Liver transplantation
The characteristics of blood recipients including diagnoses associated with transfusion and post-transfusion survival are unreported in Brazil. The goals of this analysis were: 1) to describe blood utilization according to clinical diagnoses and patient characteristics at a large public hospital, Hospital das Clinicas (HC), a tertiary teaching hospital and trauma center in the city of Sao Paulo; 2) to determine the factors associated with survival of blood recipients.
A retrospective cross-sectional analysis was conducted on all inpatients in 2004. Data came from three sources were merged: HC electronic admission files, blood issue files, and the national death registry. The first two files consist of data about patient characteristics, clinical diagnosis, and transfusion information. Analyses comparing transfused and non-transfused patients were conducted. The third file was used to determine survival status of recipients up to three years after last transfusion. Logistic regression was conducted among transfused patients to examine survival curves and characteristics associated with follow up patient survival.
In 2004, 30,779 patients were admitted to HC, with 3,835 (12.4%) transfused. These patients had 10,479 transfusions episodes, consisting of 39,561 transfused components; 16,748 (42%) red cells, 15,828 (40%) platelets and 6,190 (16%) plasma. The median number of components transfused was 3 (range 1 – 656) per patient admission. Mortality during hospitalization was dramatically different for patients whose admissions included transfusion or not (24% vs. 4%). After 1 year, 56% of transfusion recipients were alive. The multivariable model of factors associated with mortality following transfusion showed that the most significant factors in descending order were hospital ward, increasing age, increasing number of components transfused, and type of components received.
Ward and transfusion are markers of underlying medical conditions and are associated with the probability of survival. Platelet transfusions are common and likely reflect the types of patients treated at HC. This comprehensive blood utilization study, first of its kind in Brazil can help in developing transfusion policy analyses in South America.
To synthesise fluoridated hydroxyapatite (FA) crystals directly on preformed metal crowns (PMCs) and evaluate the anti-cariogenic properties in an in vitro model.
FA crystals were grown on etched PMCs and stainless steel discs and characterised by SEM. FA-coated discs allowed fluoride release to be assessed from a known surface area of FA crystals. Discs were divided into four groups (n = 6/group) and exposed to solutions at pH 4–7. Fluoride levels in solution were measured after each exposure. Twelve FA-coated and 12 non-coated PMCs were cemented onto human molars using glass ionomer (GI) or unfilled resin, making four groups of six teeth; FA-coated + GI, FA-coated + resin; non-coated + GI and non-coated + resin. Teeth were exposed to acidified gelatin (pH = 4.3) for 9 weeks.
SEM showed FA crystal growth on interior and exterior of the crowns. Average fluoride release from FA-coated discs was 0.16 mg/L/cm² at pH < 5.0. Teeth were sectioned through the lesion. Polarised microscopic examination revealed significantly smaller lesions in FA-coated crown groups compared to non-coated crown groups.
FA-coated PMCs demonstrated carious lesion preventing effects, i.e. fluoride release and reduction of demineralisation at crown/tooth interface. FA-coated crowns could be an aesthetic, inexpensive and caries preventive alternative in clinical dentistry.
Dental caries; Preformed metal crowns; Fluoridated hydroxyapatite
The title compound, C17H13ClO6, is an asymmetric alicyclic dianhydride containing a chloromethyl-substituted tetrahydronaphthalene moiety. The cyclohexene ring in the tetrahydronaphthalene moiety exhibits an envelope conformation with the tertiary C atom as the flap The dihedral angle between the two anhydride rings is 79.96 (6)°, while those between the benzene ring and the non-fused and fused anhydride rings are 71.03 (5) and 42.57 (7)°, respectively. In the crystal, molecules are connected by weak C—H⋯O interactions, forming a three-dimensional supramolecular structure.
Tumor hypoxia is an inherent impediment to cancer treatment that is both clinically significant and problematic. In this study, we performed a cell-based screen to identify small molecules that could reverse the apoptotic resistance of hypoxic cancer cells. Among the compounds we identified were a structurally-related group that sensitized hypoxic cancer cells to apoptosis by inhibiting the kinases GSK-3β and CDK1. Combinatorial inhibition of these proteins in hypoxic cancer cells and tumors increased levels of c-Myc and decreased expression of c-IAP2 and the central hypoxia response regulator Hif-1α. In mice, these compounds augmented the hypoxic tumor cell death induced by cytotoxic chemotherapy, blocking angiogenesis and tumor growth. Taken together, our findings suggest that combinatorial inhibition of GSK-3β and CDK1 augment the apoptotic sensitivity of hypoxic tumors, and they offer preclinical validation of a novel and readily translatable strategy to improve cancer therapy.
GSK-3β; CDK1; c-Myc; Hif-1α; c-IAP2; hypoxia; apoptosis; drug screen; drug resistance
We recently reported that cranial bones of Fgfr2C342Y/+ craniosynostotic mice are diminished in density when compared to those of wild type mice, and that cranial bone cells isolated from the mutant mice exhibit inhibited late stage osteoblast differentiation. To provide further support for the idea that craniosynostosis-associated Fgfr mutations lead to cell autonomous defects in osteoblast differentiation and mineralized tissue formation, here we tested bone marrow stromal cells isolated from Fgfr2C342Y/+ mice for their ability to differentiate into osteoblasts. Additionally, to determine if the low bone mass phenotype of Crouzon syndrome includes the appendicular skeleton, long bones were assessed by micro CT. Fgfr2C342Y/+ cells showed increased osteoblastic gene expression during early osteoblastic differentiation but decreased expression of alkaline phosphatase mRNA and enzyme activity, and decreased mineralization during later stages of differentiation, when cultured under 2D in vitro conditions. Cells isolated from Fgfr2C342Y/+ mice also formed less bone when allowed to differentiate in a 3D matrix in vivo. Cortical bone parameters were diminished in long bones of Fgfr2C342Y/+ mice. These results demonstrate that marrow stromal cells of Fgfr2C342Y/+ mice have an autonomous defect in osteoblast differentiation and bone mineralization, and that the Fgfr2C342Y mutation influences both the axial and appendicular skeletons.
Although homoploid hybrid speciation in plants is probably more common than previously realized, there are few well-documented cases of homoploid hybrid origin in conifers. We examined genetic divergence between two currently widespread pines in Northeast China, Pinus sylvestris var. mongolica and Pinus densiflora, and also whether two narrowly distributed pines in the same region, Pinus funebris and Pinus takahasii, might have originated from the two widespread species by homoploid hybrid speciation. Our results, based on population genetic analysis of chloroplast (cp), mitochondrial (mt) DNA, and nuclear gene sequence variation, showed that the two widespread species were divergent for both cp- and mtDNA variation, and also for haplotype variation at two of eight nuclear gene loci surveyed. Our analysis further indicated that P. sylvestris var. mongolica and P. densiflora remained allopatric during the most severe Quaternary glacial period that occurred in Northeast China, but subsequently exhibited rapid range expansions. P. funebris and P. takahasii, were found to contain a mixture of chlorotypes and nuclear haplotypes that distinguish P. sylvestris var. mongolica and P. densiflora, in support of the hypothesis that they possibly originated via homoploid hybrid speciation following secondary contact and hybridization between P. sylvestris var. mongolica and P. densiflora.
homoploid hybrid speciation; interspecific divergence; Pinus; range expansion