There are many options for urologists to treat ureteral stones that range from 8 mm to 15 mm, including ESWL and ureteroscopic holmium laser lithotripsy. While both ESWL and ureteroscopy are effective and minimally invasive procedures, there is still controversy over which one is more suitable for ureteral stones.
To perform a retrospective study to compare the efficiency, safety and complications using ESWL vs. ureteroscopic holmium laser lithotripsy in management of ureteral stones.
Between October 2010 and October 2012, 160 patients who underwent ESWL or ureteroscopic holmium laser lithotripsy at Suzhou municipal hospital for a single radiopaque ureteral stone (the size 8–15 mm) were evaluated. All patients were followed up with ultrasonography for six months. Stone clearance rate, costs and complications were compared.
Similarity in stone clearance rate and treatment time between the two procedures; overall procedural time, analgesia requirement and total cost were significantly different. Renal colic and gross hematuria were more frequent with ESWL while voiding symptoms were more frequent with ureteroscopy. Both procedures used for ureteral stones ranging from 8 to 15 mm were safe and minimally invasive.
ESWL remains first line therapy for proximal ureteral stones while ureteroscopic holmium laser lithotripsy costs more. To determining which one is preferable depends on not only stone characteristics but also patient acceptance and cost-effectiveness ratio.
As large amount of vasoactive intestinal peptide (VIP) receptors are expressed in various tumors and VIP-related diseases, radiolabeled VIP provides a potential PET imaging agent for VIP receptor. However, structural modification of VIP is required before being radiolabeled and used for VIP receptor imaging due to its poor in vivo stability. As a VIP analogue, [R8, 15, 21, L17]-VIP exhibited improved stability and receptor specificity in preliminary studies. In this study, F-18 labeled [R8,15,21, L17]-VIP was produced with the radiochemical yield being as high as 33.6% ± 3% (decay-for-corrected, n = 5) achieved within 100 min, a specific activity of 255 GBq/μmol, and a radiochemical purity as high as 99% as characterized by radioactive HPLC, TLC, and SDS-Page radioautography. A biodistribution study in normal mice also demonstrated fast elimination of F-18 labeled [R8,15,21, L17]-VIP in the blood, liver, and gastrointestinal tracts. A further micro-PET imaging study in C26 colon carcinoma bearing mice confirmed the high tumor specificity, with the tumor/muscle radioactivity uptake ratio being as high as 3.03 at 60 min following injection, and no apparent radioactivity concentration in the intestinal tracts. In addition, blocking experiment and Western Blot test further confirmed its potential in PET imaging of VIP receptor-positive tumor.
Astragali radix Antiasthmatic Decoction (AAD), a traditional Chinese medication, is found effective in treating allergic diseases and chronic cough. The purpose of this study is to determine whether this medication could suppress allergen-induced airway hyperresponsiveness (AHR) and remodeling in mice, and its possible mechanisms.
A mouse model of chronic asthma was used to investigate the effects of AAD on the airway lesions. Mice were sensitized and challenged with ovalbumin (OVA), and the extent of AHR and airway remodeling were characterized. Cells and cytokines in the bronchoalveolar lavage fluid (BALF) were examined.
AAD treatment effectively decreased OVA-induced AHR, eosinophilic airway inflammation, and collagen deposition around the airway. It significantly reduced the levels of IL-13 and TGF-β1, but exerted inconsiderable effect on INF-γ and IL-10.
AAD greatly improves the symptoms of allergic airway remodeling probably through inhibition of Th2 cytokines and TGF-β1.
Astragalus Antiasthmatic Decoction; Airway hyperresponsiveness; Airway remodeling
Francisella tularensis subsp. tularensis is a highly virulent pathogen for humans especially if inhaled. Consequently, it is considered to be a potential biothreat agent. An experimental vaccine, F. tularensis live vaccine strain, derived from the less virulent subsp. holarctica, was developed more than 50 years ago, but remains unlicensed. Previously, we developed a novel live vaccine strain, by deleting the chaperonin clpB gene from F. tularensis subsp. tularensis strain, SCHU S4. SCHU S4ΔclpB was less virulent for mice than LVS and a more effective vaccine against respiratory challenge with wild type SCHU S4. In the current study, we were interested to determine whether a similar mutant on the less virulent subsp. holarctica background would also outperform LVS in terms of safety and efficacy. To this end, clpB was deleted from clinical holarctica strain, FSC200. FSC200ΔclpB had a significantly higher intranasal LD50 than LVS for BALB/c mice, but replicated to higher numbers at foci of infection after dermal inoculation. Moreover, FSC200ΔclpB killed SCID mice more rapidly than LVS. However, dermal vaccination of BALB/c mice with the former versus the latter induced greater protection against respiratory challenge with SCHU S4. This increased efficacy was associated with enhanced production of pulmonary IL-17 after SCHU S4 challenge.
Adipose-derived stromal cells (ASCs) are pluripotent cells that have the capacity to differentiate into tendon fibroblasts (TFs). They are abundant in adults, easy to access, and are therefore an ideal cell source for tendon tissue engineering. Despite this potential, the molecular cues necessary for tenogenic differentiation of ASCs are unknown. Unlike other bone morphogenetic proteins (BMPs), BMP12, BMP13, and BMP14 have been reported to be less osteo-chondrogenic and to induce tendon rather than bone formation in vivo. This study investigated the effects of BMP12 and BMP14 on ASC differentiation in vitro. In canine ASCs, BMP12 effectively increased the expression of the tendon markers scleraxis and tenomodulin at both mRNA and protein levels. Consistent with these results, BMP12 induced scleraxis promoter driven-GFP and tenomodulin protein expression in mouse ASCs. Although BMP12 also enhanced the expression of the cartilage matrix gene aggrecan in ASCs, the resulting levels remained considerably lower than those detected in tendon fibroblasts. In addition, BMP12 reduced expression of the bone marker osteocalcin, but not the osteogenic transcription factor runx-2. BMP14 exhibited similar, but marginally less potent and selective effects, compared to BMP12. BMPs are known to signal through the canonical Smad pathway and the non-canonical mitogen-activated protein kinase (MAPK) pathway. BMP12 triggered robust phosphorylation of Smad1/5/8 but not Smad2/3 or p38 MAPK in ASCs. The effect was likely conveyed by type I receptors ALK2/3/6, as phosphorylation of Smad1/5/8 was blocked by the ALK2/3/6 inhibitor LDN-193189 but not by the ALK4/5/7 inhibitor SB-505124. Moreover, ALK6 was found to be the most abundant type I receptor in ASCs, with mRNA expression 100 to 10,000 times that of any other type I receptor. Collectively, results support the conclusion that BMP12 induces tenogenic differentiation of ASCs via the Smad1/5/8 pathway.
Cumulative effect in social contagion underlies many studies on the spread of innovation, behavior, and influence. However, few large-scale empirical studies are conducted to validate the existence of cumulative effect in information diffusion on social networks. In this paper, using the population-scale dataset from the largest Chinese microblogging website, we conduct a comprehensive study on the cumulative effect in information diffusion. We base our study on the diffusion network of message, where nodes are the involved users and links characterize forwarding relationship among them. We find that multiple exposures to the same message indeed increase the possibility of forwarding it. However, additional exposures cannot further improve the chance of forwarding when the number of exposures crosses its peak at two. This finding questions the cumulative effect hypothesis in information diffusion. Furthermore, to clarify the forwarding preference among users, we investigate both structural motif in the diffusion network and temporal pattern in information diffusion process. Findings provide some insights for understanding the variation of message popularity and explain the characteristics of diffusion network.
Creatine is a natural nitrogenous guanidino compound involved in bioenergy metabolism. Although creatine has been shown to protect neurons of the central nervous system (CNS) from experimental hypoxia/ischemia, it remains unclear if creatine may also protect CNS axons, and if the potential axonal protection depends on glial cells. To evaluate the direct impact of creatine on CNS axons, cortical axons were cultured in a separate compartment from their somas and proximal neurites using a modified two-compartment culture device. Axons in the axon compartment were subjected to acute energy depletion, an in vitro model of white matter ischemia, by exposure to 6 mM sodium azide for 30 min in the absence of glucose and pyruvate. Energy depletion reduced axonal ATP by 65%, depolarized axonal resting potential, and damaged 75% of axons. Application of creatine (10 mM) to both compartments of the culture at 24 h prior to energy depletion significantly reduced axonal damage by 50%. In line with the role of creatine in the bioenergy metabolism, this application also alleviated the axonal ATP loss and depolarization. Inhibition of axonal depolarization by blocking sodium influx with tetrodotoxin also effectively reduced the axonal damage caused by energy depletion. Further study revealed that the creatine effect was independent of glial cells, as axonal protection was sustained even when creatine was applied only to the axon compartment (free from somas and glial cells) for as little as 2 h. In contrast, application of creatine after energy depletion did not protect axons. The data provide the first evidence that creatine pretreatment may directly protect CNS axons from energy deficiency.
creatine; energy depletion; ischemia; axonal injury; ATP; white matter; compartmental culture
3,3′,4,4′,5-Pentachlorobiphenyl (PCB 126), an aryl hydrocarbon receptor (AhR) agonist and most potent dioxin-like PCB congener, significantly alters gene expression, lipid metabolism, and oxidative stress in the liver. PON1, an antioxidant and anti-atherogenic enzyme, is produced in the liver and secreted into the blood where it is incorporated into high density lipoprotein (HDL) and protects LDL and cellular membranes against lipid peroxidation. To explore the regulation of PON1, male Sprague-Dawley rats were treated with ip injections of 0, 1 or 5 μmol/kg PCB 126 and euthanized up to two weeks afterwards. Serum total and HDL-cholesterol were increased by low dose and decreased by high dose exposure, while LDL-cholesterol was unchanged. PCB 126 significantly increased hepatic PON1 gene expression and liver and serum PON1 activities. Liver and serum thiobarbituric acid reactive substances levels were not elevated except for high dose and long exposure times. Serum antioxidant capacity was unchanged across all exposure doses and time points. This study, the first describing the regulation of gene expression of PON1 by a PCB congener, raises interesting questions whether elevated PON1 is able to ameliorate PCB 126-induced lipid peroxidation and whether serum PON1 levels may serve as a new biomarker of exposure to dioxin-like compounds.
Paraoxonase 1; PCB 126; TBARS; rat; liver; AhR; plasma lipids
Background. Black people in the USA is afflicted with a higher rate of methicillin-resistant Staphylococcus aureus (MRSA) infection. This study determined the prevalence of MRSA carriage among black college students at a university setting. Methods. Hand and nasal swabs were collected and screened for MRSA by mannitol fermentation, coagulase, and DNase activities and their resistance to oxacillin. MRSA isolates were analyzed for antimicrobial resistance pattern, genetic profile for staphylococcal cassette chromosome mec (SCCmec) type, pulsed-field type, multilocus sequence type (ST), and the presence of Panton-Valentine leukocidin (PVL) gene. Results. MRSA was isolated from 1 of the 312 (0.3%) hand swabs and 2 of the 310 (0.65%) nasal swabs, respectively. All isolates lack multidrug resistance and have type IV SCCmec, characteristic of community-associated MRSA. These isolates were a ST8-MRSA-IVa-PVL(+) (USA300 strain), a ST8-MRSA-IVb-PVL(−), and a new MLST, ST2562-MRSA-IV-PVL(−), identified in this study. These isolates were thus not transmitted among students. Conclusion. We found a low rate of MRSA carriage among students in a black university. Our finding highlights the need of future study which involves multiinstitutions and other ethnic group to assess the association of black race with MRSA carriage.
Increased circulating cytokine levels are a prominent feature of aging that may contribute to atherosclerosis. However, the role vascular cells play in chronic inflammation induced by aging is not clear. Here, we examined the role of aging on inflammatory responses of vascular cells.
Methods and Results
In an ex vivo culture system, we examined the inflammatory response of aortas from young (2-4 months) and aged (16-18 months) mice under non-stimulatory conditions. We found that basal levels of interleukin (IL)-6 were increased in aged aortas. Aged aortic vascular smooth muscle cells (VSMC) exhibited a higher basal secretion of IL-6 than young VSMC. Gene and protein expression analysis revealed that aged VSMC exhibited upregulation of chemokines (e.g. CCL2), adhesion molecules (e.g., ICAM1), and innate immune receptors (e.g., Toll like receptor [TLR] 4), which all contribute to atherosclerosis. Using VSMC from aged TL4-/- and Myd88-/- mice, we demonstrate that signaling via TLR4 and its signal adaptor, MyD88, are in part responsible for the age-elevated basal IL-6 response.
Aging induces a proinflammatory phenotype in VSMC due in part to increased signaling of TLR4 and MyD88. Our results provide a potential explanation as to why aging leads to chronic inflammation and enhanced atherosclerosis.
aging; atherosclerosis; inflammation; mouse; vascular smooth muscle cells
Manipulation is an important issue for both developed and emerging stock markets. Many efforts have been made to detect manipulation in stock markets. However, it is still an open problem to identify the fraudulent traders, especially when they collude with each other. In this paper, we focus on the problem of identifying the anomalous traders using the transaction data of eight manipulated stocks and forty-four non-manipulated stocks during a one-year period. By analyzing the trading networks of stocks, we find that the trading networks of manipulated stocks exhibit significantly higher degree-strength correlation than the trading networks of non-manipulated stocks and the randomized trading networks. We further propose a method to detect anomalous traders of manipulated stocks based on statistical significance analysis of degree-strength correlation. Experimental results demonstrate that our method is effective at distinguishing the manipulated stocks from non-manipulated ones. Our method outperforms the traditional weight-threshold method at identifying the anomalous traders in manipulated stocks. More importantly, our method is difficult to be fooled by colluded traders.
Age-related decline in immunity can impair cell-mediated responses during an infection, malignancy, and acute allograft rejection. Although much research has been allocated to understand the immune responses that impact the former two conditions, the cellular mechanisms by which aging impacts the immune acceptance of organ allografts are not completely clear. In this study, we examined how recipient age impacts the efficacy of therapies that modulate immune recognition of allografts using an immunogenic murine skin transplant model. We found that costimulatory blockade-based treatment failed to extend allograft survival in older recipients to the same extent as that observed in younger recipients. CD8+ T-cells were critical for the inability of aged recipients to achieve maximal allograft survival. Although aged mice displayed a larger number of effector memory T-cells prior to transplantation, these cells did not exhibit enhanced alloreactivity compared to young memory T-cells. In contrast, naïve aged CD8+ T-cells exhibited enhanced IFN-γ production to allostimulation compared to young naïve T-cells. Our results provide evidence that aging enhances CD8+ T-cell alloreactivity. This could impair the ability of costimulatory blockade-based therapies to prolong allograft survival. Thus, targeting CD8+ T cells in humans may be a way to improve outcomes in older patients requiring immune modulatory therapy.
The human X and Y chromosomes evolved from an ordinary pair of autosomes during the past 200–300 million years1–3. Due to genetic decay, the human MSY (male-specific region of Y chromosome) retains only three percent of the ancestral autosomes’ genes4,5. This evolutionary decay was driven by a series of five “stratification” events. Each event suppressed X-Y crossing over within a chromosome segment or “stratum”, incorporated that segment into the MSY, and subjected its genes to the erosive forces that attend the absence of crossing over2,6. The last of these events occurred 30 million years ago (mya), or 5 million years before the human and Old World monkey (OWM) lineages diverged. Although speculation abounds regarding ongoing decay and looming extinction of the human Y chromosome7–10, remarkably little is known about how many MSY genes were lost in the human lineage in the 25 million years that have followed its separation from the OWM lineage. To explore this question, we sequenced the MSY of the rhesus macaque, an OWM, and compared it to the human MSY. We discovered that, during the last 25 million years, MSY gene loss in the human lineage was limited to the youngest stratum (stratum 5), which comprises three percent of the human MSY. Within the older strata, which collectively comprise the bulk of the human MSY, gene loss evidently ceased more than 25 mya. Likewise, the rhesus MSY has not lost any older genes (from strata 1–4) during the past 25 million years, despite major structural differences from the human MSY. The rhesus MSY is simpler, with few amplified gene families or palindromes that might enable intrachromosomal recombination and repair. We present an empirical reconstruction of human MSY evolution in which each stratum transitioned from rapid, exponential loss of ancestral genes to strict conservation through purifying selection.
Immune tolerance to transplanted organs is impaired when the innate immune system is activated in response to the tissue necrosis that occurs during harvesting and implantation procedures. A key molecule in this immune pathway is the intracellular TLR signal adaptor known as myeloid differentiation primary response gene 88 (MyD88). After transplantation, MyD88 induces DC maturation as well as the production of inflammatory mediators, such as IL-6 and TNF-α. However, upstream activators of MyD88 function in response to transplantation have not been identified. Here, we show that haptoglobin, an acute phase protein, is an initiator of this MyD88-dependent inflammatory process in a mouse model of skin transplantation. Necrotic lysates from transplanted skin elicited higher inflammatory responses in DCs than did nontransplanted lysates, suggesting DC-mediated responses are triggered by factors released during transplantation. Analysis of transplanted lysates identified haptoglobin as one of the proteins upregulated during transplantation. Expression of donor haptoglobin enhanced the onset of acute skin transplant rejection, whereas haptoglobin-deficient skin grafts showed delayed acute rejection and antidonor T cell priming in a MyD88-dependent graft rejection model. Thus, our results show that haptoglobin release following skin necrosis contributes to accelerated transplant rejection, with potential implications for the development of localized immunosuppressive therapies.
To investigate the levels for some specified microRNAs in human’s peripheral blood so as to determine whether they can serve as biomarkers for metastatic non-small-cell lung cancer.
Use a quantitative stem-loop RT-PCR method to examine the serum levels for certain microRNAs including has-miR-125a-5p, has-miR-126, has-miR-183, has-miR-200, has-miR-221, and has-miR-222 from the patients with Stage IV, Stage I/II non-small-cell lung cancer and the controls.
There was statistical difference in the serum levels for hsa-miR-126, hsa-miR-183, and hsa-miR-222 between the controls and the Stage IV patients, but not for has-miR-125a-5p, has-miR-200 and has-miR-221. It also showed statistical difference for hsa-miR-126 and hsa-miR-183 between the Stage I/II patients and Stage IV patients, but not between the controls and Stage I/II patients.
Hsa-miR-126 and hsa-miR-183 may serve as potential serum biomarkers for metastatic non-small-cell lung cancer.
microRNAs; Non-small-cell lung cancer; Stem-loop RT-PCR; Biomarker
Objective: Mitogen-activated protein kinases (MAPKs) are correlated with a more malignant phenotype in many cancers. This study was designed to evaluate the predictive value of the expression of MAPK phosphatase-1 (MKP-1) and phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), as the key regulatory mechanism of the MAPKs, in lung squamous cell carcinoma (SCC). Methods: We assessed the expressions of MKP-1 and p-ERK1/2 in twenty subjects at different differentiation degree of SCC and five normal lungs by immunohistochemistry and real-time reverse transcriptase polymerase chain reaction (RT-PCR) analysis. Results: Immunohistochemistry and real-time RT-PCR assay showed that the expression of MKP-1 was gradually decreased as tissue type went from normal lung tissues to increasingly undifferentiated carcinoma, and it was negatively correlated with tumor differentiation (P<0.01). However, the expression of p-ERK1/2 or ERK1/2 was gradually increased as tissue type went from normal lung tissues to increasingly undifferentiated carcinoma, and it was positively correlated with tumor differentiation (P<0.01). Conclusions: Our data indicates the relevance of MKP-1 and p-ERK1/2 in SCC as a potential positive and negative prognostic factor. The imbalanced expression of MKP-1 and p-ERK1/2 may play a role in the development of SCC and these two molecules may be new targets for the therapy and prognosis of SCC.
Mitogen-activated protein kinase phosphatase-1 (MKP-1); Extracellular signal-regulated kinase (ERK); Lung squamous cell carcinoma (SCC); Prognostic factor
Targeting drugs to receptors involved in tumor angiogenesis is considered to be a novel and promising approach to improve cancer treatment. This study aimed to evaluate the anti-tumor efficacy of 188Re-labeled recombinant human plasminogen kringle 5 (188Re‑rhk5) through [18F]-fluorodeoxyglucose (FDG) micro-positron emission tomography (PET). Radiolabeled rhk5 was obtained by conjugating the hystidine (6 x His) group at the carbon end of rhk5 with fac-[188Re(H2O)3(CO)3]+. The biodistribution study of 188Re-rhk5 showed that 188Re-rhk5 had a high initial tumor uptake and prolonged tumor retention. The highest tumor uptake of 188Re-rhk5 (3.65±0.82% ID/g) was found 2 h after injection which decreased to 0.81±0.14% ID/g 12 h after injection. Following therapy, tumor size measurement indicated that 188Re-rhk5-treated tumors were smaller than 188Re-, rhk5- and saline-treated controls 6 days after the treatment. In vivo 18F-FDG micro-PET imaging showed significantly reduced tumor metabolism in the 188Re-rhk5-treated mice vs. those treated with rhk5, 188Re and saline control, 1 day after treatment. Moreover, the number of microvessels was significantly reduced after 188Re-rhk5 treatment as determined by CD31 staining. Our results demonstrate that specific delivery of 188Re-rhk5 allows preferential cytotoxicity to A549 lung cancer cells and tumor vasculature. 18F-FDG micro-PET is a non-invasive imaging tool that can be utilized to assess early tumor responses to 188Re-rhk5 therapy.
AIM: To compare the efficacy and safety of paclitaxel combined with fluorouracil plus cisplatin (PCF), and oxaliplatin combined with fluorouracil plus leucovorin (FOLFOX-4) regimens for advanced gastric cancer (AGC).
METHODS: Ninety-four patients with AGC were randomly assigned to receive paclitaxel (50 mg/m2 iv) on days 1, 8 and 15, cisplatin (20 mg/m2 iv) and fluorouracil (750 mg/m2 iv) on days 1-5, or oxaliplatin (85 mg/m2 iv) and leucovorin (200 mg/m2 iv) on day 1, followed by bolus fluorouracil (400 mg/m2 iv) and fluorouracil (600 mg/m2 iv) on days 1 and 2. The primary end point was the 1-year survival time.
RESULTS: The overall response rate (ORR) of the patients was 48.0% and 45.5% to PCF and FOLFOX-4, respectively. The disease control rate (DCR) of PCF and FOLFOX-4 was 82.0% and 81.8%, respectively. The median survival times (MSTs) of the patients were 10.8 and 9.9 mo, respectively, after treatment with PCF and FOLFOX-4. The 1-year survival rate of the patients was 36.0% and 34.1%, respectively, after treatment with PCF and FOLFOX-4. No significant difference was observed in ORR, DCR, MST or 1-year survival rate between the two groups. The most common adverse events were anemia, nausea and vomiting, and grade 3/4 alopecia in PCF treatment group, and anemia, grade 1/2 neurotoxic effect and grade 3/4 neutropenia in FOLFOX-4 treatment group.
CONCLUSION: Patients with AGC have a similar response rate to PCF and FOLFOX-4 regimens with a similar survival rate. The PCF and FOLFOX-4 regimens are efficacious and tolerable as a promising therapy for AGC.
Paclitaxel; Oxaliplatin; Advanced gastric cancer
Francisella tularensis subspecies tularensis is a highly virulent facultative intracellular pathogen of humans and a potential biological weapon. A live vaccine strain, F. tularensis LVS, was developed more than 50 years ago by pragmatic attenuation of a strain of the less virulent holarctica subspecies. LVS was demonstrated to be highly effective in human volunteers who were exposed to intradermal challenge with fully virulent subsp. tularensis, but was less effective against aerosol exposure. LVS faces regulatory hurdles that to date have prevented its licensure for general use. Therefore, a better defined and more effective vaccine is being sought. To this end we have created gene deletion mutants in the virulent subsp. tularensis strain and tested them for their ability to elicit a protective immune response against systemic or aerosol challenge with the highly virulent wild-type subsp. tularensis strain, SCHU S4. Both oral and Intradermal (ID) primary vaccination routes were assessed in BALB/c and C3H/HeN mice as was oral boosting. One SCHU S4 mutant missing the heat shock gene, clpB, was significantly more attenuated than LVS whereas a double deletion mutant missing genes FTT0918 and capB was as attenuated as LVS. In general mice immunized with SCHU S4ΔclpB were significantly better protected against aerosol challenge than mice immunized with LVS. A single ID immunization of BALB/c mice with SCHU S4ΔclpB was at least as effective as any other regimen examined. Mice immunized with SCHU S4Δ0918ΔcapB were generally protected to a similar degree as mice immunized with LVS. A preliminary examination of immune responses to vaccination with LVS, SCHU S4ΔclpB, or SCHU S4Δ0918ΔcapB provided no obvious correlate to their relative efficacies.
Francisella tularensis is a facultative intracellular bacterial pathogen and the etiological agent of tularemia. The subspecies F. tularensis tularensis is especially virulent for humans when inhaled and respiratory tularemia is associated with high mortality if not promptly treated. A live vaccine strain (LVS) derived from the less virulent holarctica subspecies confers incomplete protection against aerosol challenge with subsp. tularensis. Moreover, correlates of protection have not been established for LVS.
In the present study we compare molecular immune responses elicited by LVS and two defined deletion mutants of clinical subsp. tularensis strain, SCHU S4, that confer enhanced protection in a mouse model. BALB/c mice were immunized intradermally then challenged with an aerosol of SCHU S4 six weeks later. Changes in the levels of a selected panel of cytokines and chemokines were examined in the lungs, spleens, and sera of vaccinated and challenged mice. Mostly, increased cytokine and chemokine levels correlated with increased bacterial burden. However, after adjusting for this variable, immunization with either of the two Schu S4 mutants resulted in higher levels of several pulmonary cytokines, versus those resulting after LVS immunization, including IL-17. Moreover, treatment of mice immunized with ΔclpB with anti-IL-17 antibodies post-challenge enhanced lung infection.
This is the first report characterizing local and systemic cytokine and chemokine responses in mice immunized with vaccines with different efficacies against aerosol challenge with virulent F. tularensis subsp. tularensis. It shows that increases in the levels of most of these immunomodulators, including those known to be critical for protective immunity, do not superficially correlate with protection unless adjusted for the effects of bacterial burden. Additionally, several cytokines were selectively suppressed in the lungs of naïve mice, suggesting that one mechanism of vaccine action is to overcome this pathogen-induced immunosuppression.
As increasing numbers of elderly patients require solid organ transplantation, the need to better understand how aging modifies alloimmune responses increases. Here, we examined whether aged mice exhibit augmented, donor-specific memory responses prior to transplantation. We found that elevated donor-specific IL-17, but not IFN-γ, responses were observed in aged mice compared to young mice prior to transplantation. Further characterization of the heightened IL-17 alloimmune response with aging demonstrated that memory CD4+ T cells were required. Reduced IL-2 alloimmune responses with age contributed to the elevated IL-17 phenotype in vitro, and treatment with an anti-IL-17 antibody delayed the onset of acute allograft rejection. In conclusion, aging leads to augmented, donor-specific IL-17 immune responses that are important for the timing of acute allograft rejection in aged recipients. IL-17 targeting therapies may be useful for averting transplant rejection responses in older transplant recipients.
TLR4 is a unique TLR as downstream signaling occurs via two separate pathways: MyD88 and TRIF. Here, we compared and contrasted the interplay of these pathways between murine dendritic cells (DCs) and macrophages during LPS stimulation. During TLR4 activation, neither pathway on its own was critical for upregulation of costimulatory molecules in DCs, whereas the upregulation of costimulatory molecules was largely TRIF-dependent in macrophages. LPS-induced secreted factors, of which type I IFNs were one of the active components, played a larger role in promoting the upregulation of costimulatory molecules in macrophages than DCs. In both cell types, MyD88 and TRIF pathways together accounted for the inflammatory response to LPS activation. Furthermore, signaling of both adaptors allowed maximal T cell priming by LPS-matured DCs, with MyD88 playing a larger role than TRIF. In sum, in our experimental systems, TRIF signaling plays a more important role in LPS-induced macrophage activation than in DC activation.
Rodent; dendritic cell
The type A subspecies of Francisella tularensis is a highly virulent facultative intracellular bacterial pathogen, and a potential biological weapon. Recently, there has been renewed interest in developing new vaccines and therapeutics against this bacterium. Natural cases of disease, tularemia, caused by the type A subspecies are very rare. Therefore, the United States Food and Drug Administration will rely on the so called Animal Rule for efficacy testing of anti-Francisella medicines. This requires the human disease to be modeled in one or more animal species in which the pathogenicity of the agent is reasonably well understood. Mice are natural hosts for F. tularensis, and might be able to satisfythis requirement. Tularemia pathogenesis appears to be primarily due to the host inflammatory responsewhich is poorly understood at the molecular level. Additionally, the extent to which this response varies depending on host and pathogen genetic background, or by pathogen challenge route or dose is unknown. Therefore, the present study examined sera and infected tissues from C57BL/6 and BALB/c mice challenged by natural intradermal and respiratory routes with one of two distinct type A strains of the pathogen for cytokine and chemokine responses that might help explain the morbidity associated with tularemia. The results show that the molecular immune response was mostly similar regardless of the variables examined. For instance, mRNA for the proinflammatory cytokine IL-6, and chemokines KC, and IP-10 was consistently upregulated at all sites of infection. Upregulation of mRNA for several other cytokines and chemokines occurred in a more tissue restricted manner. For instance, IFNIFN-γ was highly upregulated in the skin of BALB/c, but not C57BL/6 mice after ID inoculation of the pathogen, whilst IL-10 mRNA upregulation was only consistently seen in the skin and lungs.
Determining the genetic basis of cancer requires comprehensive analyses of large collections of histopathologically well-classified primary tumours. Here we report the results of a collaborative study to discover somatic mutations in 188 human lung adenocarcinomas. DNA sequencing of 623 genes with known or potential relationships to cancer revealed more than 1,000 somatic mutations across the samples. Our analysis identified 26 genes that are mutated at significantly high frequencies and thus are probably involved in carcinogenesis. The frequently mutated genes include tyrosine kinases, among them the EGFR homologue ERBB4; multiple ephrin receptor genes, notably EPHA3; vascular endothelial growth factor receptor KDR; and NTRK genes. These data provide evidence of somatic mutations in primary lung adenocarcinoma for several tumour suppressor genes involved in other cancers—including NF1, APC, RB1 and ATM—and for sequence changes in PTPRD as well as the frequently deleted gene LRP1B. The observed mutational profiles correlate with clinical features, smoking status and DNA repair defects. These results are reinforced by data integration including single nucleotide polymorphism array and gene expression array. Our findings shed further light on several important signalling pathways involved in lung adenocarcinoma, and suggest new molecular targets for treatment.
Francisella tularensis is a highly virulent human pathogen. The most virulent strains belong to subspecies tularensis and these strains cause a sometimes fatal disease. Despite an intense recent research effort, there is very limited information available that explains the unique features of subspecies tularensis strains that distinguish them from other F. tularensis strains and that explain their high virulence. Here we report the use of targeted mutagenesis to investigate the roles of various genes or pathways for the virulence of strain SCHU S4, the type strain of subspecies tularensis.
The virulence of SCHU S4 mutants was assessed by following the outcome of infection after intradermal administration of graded doses of bacteria. By this route, the LD50 of the SCHU S4 strain is one CFU. The virulence of 20 in-frame deletion mutants and 37 transposon mutants was assessed. A majority of the mutants did not show increased prolonged time to death, among them notably ΔpyrB and ΔrecA. Of the remaining, mutations in six unique targets, tolC, rep, FTT0609, FTT1149c, ahpC, and hfq resulted in significantly prolonged time to death and mutations in nine targets, rplA, wbtI, iglB, iglD, purL, purF, ggt, kdtA, and glpX, led to marked attenuation with an LD50 of >103 CFU. In fact, the latter seven mutants showed very marked attenuation with an LD50 of ≥107 CFU.
The results demonstrate that the characterization of targeted mutants yielded important information about essential virulence determinants that will help to identify the so far little understood extreme virulence of F. tularensis subspecies tularensis.