Ang-(1-7) might prevent the development of monocrotaline induced pulmonary arterial hypertension in rats

OBJECTIVES

To investigate whether Angiotensin-(1-7) [Ang-(1-7)] could prevent the development of monocrotaline (MCT) induced pulmonary arterial hypertension and vascular remodeling.

MATERIALS AND METHODS

30 Sprgue-Dawely rats were randomly assigned into three groups: control group, pulmonary arterial hypertension (PAH) group and PAH +Ang-(1-7) group. Rats in PAH group and PAH +Ang-(1-7) group received 60 mg/kg monocrotaline (MCT) injection subcutaneously and after 24 hours received either saline or 24 microg/kg/h of Ang-(1-7) injection via osmotic minipumps for 4 weeks. Those rats in control group were firstly injected saline subcutaneously and then received saline injection via osmotic minipumps.

RESULTS

After four weeks, in PAH group, right ventricular systolic pressure (RVSP), right ventricular hypertrophy index (RVHI), percentage of wall thickness (WT%) and percentage of wall area (WA%) were significantly increased, and the level of endothelial nitric oxide synthase (eNOS) protein, eNOS ser 1177-phosphorylati, Akt-phosphorylation were significantly decreased compared with control group. However, RVSP, RVHI, WT%, WA% were dramatically decreased in PAH+Ang-(1-7) group and the level of eNOS protein, eNOS ser 1177-phosphorylation, Akt-phosphorylation were significantly increased compared with PAH group.

CONCLUSION

Those results suggest that Ang-(1-7) could prevent the development of monocrotaline induced pulmonary arterial hypertension and vascular remodeling, which appears to be associated with up-regulation of eNOS activation via Akt pathway.

Luminal serotonin time-dependently modulates vagal afferent driven antinociception in response to colorectal distention in rats

BACKGROUND

Compelling evidence shows that vagal afferents mediate antinociception in response to visceral insults. Our recent findings implied that luminal serotonin (5-hydroxytryptamine, 5-HT) might mediate chronic food allergen sensitized visceral hyperalgesia, in which vagal afferents might be implicated. Here, to test this hypothesis, we investigated the effects of luminal infused 5-HT on visceral nociception and the involvement of vagal antinociceptive pathway.

METHODS

The vagus-intact or vagotomized rats were given acute intraluminally or intraperitoneally administered 5-HT, or chronic luminal infusion of 5-HT. The visceromotor response (VMR) to colorectal distension (CRD) was electrophysiologically recorded.

KEY RESULTS

Acute intraluminal infusion of 5-HT (10 or 100 nmol) significantly attenuated VMR to CRD, while systemic administered 5-HT at similar doses resulted in markedly augmented nociception. Pretreatment with luminal application of granisetron or lidocaine, or pharmacological depletion of endogenous 5-HT with injection of p-chlorophenylalanine, a 5-HT synthesis inhibitor, and subdiaphragmatic vagotomy or functional deafferentation with capsaicin abolished the effect of luminal (but not systemic) 5-HT. Chronic infusion of 5-HT (10 nmol d(-1) for 5 days) produced gradual augmentation of baseline VMR. And, the VMR to CRD after 5-HT infusion decreased on day 1 and 2, then gradually increased from day 3. Surgical vagotomy or daily preperfusion with granisetron canceled these time-dependent patterns.

CONCLUSIONS & INFERENCES

Luminal 5-HT time-dependently modulates vagal afferent driven antinociception. Acute infusion of 5-HT attenuates visceral nociception via activation of vagal afferent 5-HT type 3 receptors (5-HT(3)Rs)within intestinal mucosa; while chronic luminal 5-HT caused gradually developed visceral hyperalgesia, which may also involve vagal 5-HT(3)Rs.

Purification and characterization of two new allergens from the salivary glands of the horsefly, Tabanus yao

BACKGROUND

Horsefly bite can cause allergic reactions in humans. There is no information about allergenic horsefly proteins.

OBJECTIVES

The current work aims to purify and characterize IgE-binding proteins from horsefly salivary glands.

METHODS

Two IgE-binding proteins, Tab a 1 and Tab a 2 with molecular weight of 26 and 35 kd, respectively, were purified and characterized from 60,000 pairs of horsefly salivary glands of Tabanus yao, respectively. Their primary sequences were determined by Edman degradation and cDNA cloning. Their allergenicity was examined using enzyme-linked immunosorbent assay (ELISA), ELISA inhibition tests, and immunoblots.

RESULTS

Immunoblotting demonstrated IgE binding by 32 and 34 of 37 (86.5% and 91.8%) subjects' sera to Tab a 1 and Tab a 2, respectively. They were identified as an antigen 5-related (Ag 5) protein and hyaluronidase, respectively. ELISA inhibitions of serum IgE reactivity to the horsefly salivary gland extract (SGE) using purified Tab a 1 and Tab a 2 were significant (about 45%). In addition, these proteins showed some IgE-binding capacity to sera of subjects with wasp sting allergy.

CONCLUSIONS

We have first identified and characterized two IgE-binding proteins, Tab a 1, an Ag 5-like protein and Tab a 2, a hyaluronidase, from the horsefly salivary glands. They appear to be of importance for the allergic reactions induced by horsefly bite. These allergens are thus not only found in stinging but also found in hematophagous insects. These results also provided support for the presence of the so-called wasp-horsefly syndrome (WHS).

Adenosine 2A receptor is protective against renal injury in MRL/lpr mice

OBJECTIVE

Adenosine is considered as a potent endogenous anti-inflammatory and immunosuppressive molecule. We examined the roles of A2A-adenosine receptor (A(2A)R) in the progression of lupus nephritis.

METHODS

MRL/lpr mice were given a selective A(2A)R agonist, CGS21680 (0.4 mg/kg per day, i.p.) while control mice received saline only. After 8 weeks of treatment, mice were sacrificed for assessment of functional and histological parameters as well as inflammatory infiltration in the kidneys. MCP-1, IFN-γ, MHC-II and A(2A)R mRNA expression was evaluated by RT-PCR. Expression of A(2A)R and nuclear NFκB p65 protein was determined by Western blot analysis. Levels of anti-dsDNA antibody and IFN-γ were measured by ELISA.

RESULTS

CGS21680 treatment resulted in significant decrease in proteinuria, blood urea and creatinine as well as improvement in renal histology. Renal macrophage and T-cell infiltration were significantly attenuated in association with suppressed expression of MCP-1, IFN-γ and MHC-II. CGS21680 treatment reduced the level of serum anti-dsDNA and renal immune complex deposition. CGS21680 inhibited the activation of NFκB and suppressed the expression of IFN-γ, MCP-1 and MHC-II in MRL/lpr splenocytes.

CONCLUSIONS

A(2A)R activation suppressed inflammation in the kidneys of MRL/lpr mice and can be considered as a novel therapeutic approach for human lupus nephritis.

Susceptibility of North-American and European crickets to Acheta domesticus densovirus (AdDNV) and associated epizootics

The European house cricket, Acheta domesticus L., is highly susceptible to A. domesticus densovirus (AdDNV). Commercial rearings of crickets in Europe are frequently decimated by this pathogen. Mortality was predominant in the last larval stage and young adults. Infected A. domesticus were smaller, less active, did not jump as high, and the adult females seldom lived more than 10-14 days. The most obvious pathological change was the completely empty digestive caecae. Infected tissues included adipose tissue, midgut, epidermis, and Malpighian tubules. Sudden AdDNV epizootics have decimated commercial mass rearings in widely separated parts of North America since the autumn of 2009. Facilities that are producing disease-free crickets have avoided the importation of crickets and other non-cricket species (or nonliving material). Five isolates from different areas in North America contained identical sequences as did AdDNV present in non-cricket species collected from these facilities. The North American AdDNVs differed slightly from sequences of European AdDNV isolates obtained in 1977, 2004, 2006, 2007 and 2009 and an American isolate from 1988. The substitution rate of the 1977 AdDNV 5kb genome was about two nucleotides per year, about half of the substitutions being synonymous. The American and European AdDNV strains are estimated to have diverged in 2006. The lepidopterans Spodoptera littoralis and Galleria mellonella could not be infected with AdDNV. The Jamaican cricket, Gryllus assimilis, and the European field cricket, Gryllus bimaculatus, were also found to be resistant to AdDNV.

Development of gold standard ion-selective electrode-based methods for fluoride analysis

BACKGROUND/AIMS

Currently available techniques for fluoride analysis are not standardized. Therefore, this study was designed to develop standardized methods for analyzing fluoride in biological and nonbiological samples used for dental research.

METHODS

A group of nine laboratories analyzed a set of standardized samples for fluoride concentration using their own methods. The group then reviewed existing analytical techniques for fluoride analysis, identified inconsistencies in the use of these techniques and conducted testing to resolve differences. Based on the results of the testing undertaken to define the best approaches for the analysis, the group developed recommendations for direct and microdiffusion methods using the fluoride ion-selective electrode.

RESULTS

Initial results demonstrated that there was no consensus regarding the choice of analytical techniques for different types of samples. Although for several types of samples, the results of the fluoride analyses were similar among some laboratories, greater differences were observed for saliva, food and beverage samples. In spite of these initial differences, precise and true values of fluoride concentration, as well as smaller differences between laboratories, were obtained once the standardized methodologies were used. Intraclass correlation coefficients ranged from 0.90 to 0.93, for the analysis of a certified reference material, using the standardized methodologies.

CONCLUSION

The results of this study demonstrate that the development and use of standardized protocols for F analysis significantly decreased differences among laboratories and resulted in more precise and true values.

Clinicopathological implications of tumour-associated macrophages and vascularization in sinonasal melanoma

This study investigated tumour-associated macrophages (TAMs) and their effects on tumour vascularization in sinonasal melanoma (SNM). Data on 45 patients with SNM undergoing surgery were reviewed retrospectively. Tumour sections were analysed immunohistochemically for TAMs, microvessels, lymph vessels, and vasculogenic mimicry in both intra- and peritumoural areas. The density of intratumoural TAMs was associated with tumour thickness and with overall survival in SNM stages I and II but there were no correlations between micro- or lymph vessel density and TAM infiltration. Greater TAM infiltration was observed in tumour tissues with vasculogenic mimicry although this was not statistically significant. These data suggest that high intratumoural TAM infiltration is associated with tumour aggressiveness and a poor prognosis for SNM, and that activation of macrophages can be polarized by different micro-environments. TAMs could be potential prognostic indicators for patients with SNM.

Synchronous multicentric osteosarcoma involving mandible and maxillas

Synchronous multicentric osteosarcoma (SMO) is rare with fewer than 100 well-documented cases in the medical literature. SMO affecting the jaw is even rarer with only three cases involving the mandible having been reported. SMO in the maxilla has not been previously reported. The authors report the first case of SMO involving both mandible and maxilla in an 18-year-old girl. The clinical course, radiological and histological appearance of the lesion indicated it was an SMO rather than metastasis arising from a single osteosarcoma. This case could be regarded as powerful evidence to support the multicentric theory related to SMO.

Treatment of a fusiform vertebral aneurysm with double stent placement. A technical case report and review of the literature

A 34-year-old man admitted to another hospital presented with sudden onset of headache. The CT scan was unremarkable, but magnetic resonance angiography revealed a fusiform aneurysm in the left vertebral artery. Six days later, the patient was sent to our institution for further diagnosis and treatment. Cerebral angiography confirmed a fusiform aneurysm located in the right vertebral artery. At first, we placed a neuroform-3 stent and could see contrast medium stasis in the aneurysm, so we did not fill coils into the aneurysm. Four months later, the patient was admitted for rechecking. DSA showed the aneurysm remained and we placed a LEO stent in the lumen of the Neuroform stent. A control DSA eight months later showed the aneurysm had almost healed. Overlapping stents may induce spontaneous thrombosis of vertebral artery aneurysms and facilitate parent artery reconstruction through flow remodeling and stent endothelialization. This technique may be an option in treating dissecting or fusiform intracranial aneurysms that are not amenable to open surgical treatment or endovascular coil embolization.

Successful Management of Hemorrhagic Complications during Onyx-18 Embolization of Cerebral Arteriovenous Malformations

The most frequent and devastating complication of the endovascular treatment of cerebral AVMs is hemorrhage. This report describes three patients with cerebral AVM who encountered bleeding during Onyx-18 embolization. The bleeding was discovered promptly during the procedure and hemorrhage quickly prevented using Onyx-18. All three patients recovered without any new neurological symptoms. Early detection and prevention of bleeding are very important during interventional procedures to avoid craniotomy and improve the prognosis of patients.

Magnetic and upconverted luminescent properties of multifunctional lanthanide doped cubic KGdF4 nanocrystals

Lanthanide (Ln3+) doped KGdF4 (Ln=Yb3+, Er3+, Ho3+, Tm3+) nanocrystals with a mean diameter of approximately 12 nm were synthesized by a hydrothermal method using oleic acid as a stabilizing agent at 180 °C. The nanocrystals crystallize in the cubic phase as α-NaGdF4. When excited by a 980 nm laser, these Ln3+ doped nanocrystals exhibit multicolor up-conversion (UC) emissions in red, yellow, blue and white. The calculated color coordinates demonstrate that white UC emission (CIE-X=0.352, CIE-Y=0.347) can be obtained by varying the dopant concentrations in the Yb3+/Ho3+/Tm3+ triply-doped nanocrystals to yield different RGB emission intensities. The measured field dependence of magnetization (M-H curves) of the KGdF4 nanocrystals shows their paramagnetic characteristics that can be ascribed to the non-interacting localized nature of the magnetic moment of Gd3+ ions. Moreover, low temperature thermal treatment can enhance UC properties, magnetization and magnetic mass susceptibility of Ln3+ doped KGdF4 nanocrystals. The multifunctional Ln3+ doped KGdF4 nanocrystals have potential applications in color displays, bioseparation, and optical-magnetic dual modal nanoprobes in biomedical imaging.

Nociceptive afferent activity alters the SI RA neuron response to mechanical skin stimulation

Procedures that reliably evoke cutaneous pain in humans (i.e., 5-7 s skin contact with a 47-51 °C probe, intradermal algogen injection) are shown to decrease the mean spike firing rate (MFR) and degree to which the rapidly adapting (RA) neurons in areas 3b/1 of squirrel monkey primary somatosensory cortex (SI) entrain to a 25-Hz stimulus to the receptive field center (RF(center)) when stimulus amplitude is "near-threshold" (i.e., 10-50 μm). In contrast, RA neuron MFR and entrainment are either unaffected or enhanced by 47-51 °C contact or intradermal algogen injection when the amplitude of 25-Hz stimulation is 100-200 μm (suprathreshold). The results are attributed to an "activity dependence" of γ-aminobutyric acid (GABA) action on the GABA(A) receptors of RA neurons. The nociceptive afferent drive triggered by skin contact with a 47-51 °C probe or intradermal algogen is proposed to activate nociresponsive neurons in area 3a which, via corticocortical connections, leads to the release of GABA in areas 3b/1. It is hypothesized that GABA is hyperpolarizing/inhibitory and suppresses stimulus-evoked RA neuron MFR and entrainment whenever RA neuron activity is low (as when the RF(center) stimulus is weak/near-threshold) but is depolarizing/excitatory and augments MFR and entrainment when RA neuron activity is high (when the stimulus is strong/suprathreshold).

Endovascular treatment for cerebral aneurysms using stents

Endovascular stent placement combined with coil embolization is an established procedure for the treatment of intracranial aneurysms. We describe lesion outcome using stents for the treatment of intracranial aneurysms. Sixty-nine patients (30 females and 39 males; age range 12-78 years) treated with stent placement at Beijing Tiantan Hospital over a six-year period. Seventy- six cerebral aneurysms were encountered and 74 lesions were treated with 79 stents. Outcome was evaluated using the Glasgow Outcome Scale (GOS) score during a mean follow-up period of 32 months. Of the 74 stented aneurysms, 34 (45.9%) were located in the anterior circulation and 40 (54.1%) in the posterior circulation. Forty-eight (64.9%) aneurysms were small and 26 (35.1%) were large or giant. In 67 (90.5%) aneurysms embolization was completed by packing the aneurysm sac with platinum coils. In five small fusiform and four saccular aneurysms, the stent was used alone. Six procedure-related complications were observed and a cause of death in 7.2% of the patients. Follow-up angiography obtained at three months to one year in 68 (91.9%) aneurysms demonstrated complete occlusion in 43 aneurysms with a progressive thrombosis rate of 19.4% (six out of 31 aneurysms). Aneurysm recurrence occurred in four (5.8%) patients, three were treated with coil embolization and one with placement of another stent. Overall long-term outcome was good (GOS Score 4 or 5) in 92.8%, and fatal (GOS Score 1) in 7.2% of the patients. Intracranial stents can be a useful addition to coil embolization for complex broad-based aneurysms. Favorable overall long-term outcome can be achieved in 92.8% of patients when using endovascular stent placement techniques.

Downregulation of caspase-9 is a frequent event in patients with stage II colorectal cancer and correlates with poor clinical outcome

OBJECTIVE

 To evaluate the clinical significance of caspase-9 mRNA expression and investigate its prognostic value in stage II colorectal cancer.

METHOD

Quantitative real-time RT-PCR was used to analyse caspase-9 mRNA expression in cancer tissue and corresponding normal mucosa from 120 patients.

RESULTS

Compared with normal mucosa, the expression of caspase-9 mRNA was found to be downregulated in cancer tissue (P = 0.001). Poorly differentiated cancer showed lower mRNA expression than cancer with greater differentiation (P = 0.031). The Kaplan-Meier survival analysis demonstrated that patients with downregulated caspase-9 showed a worse overall survival (P = 0.012) and disease-free survival (P = 0.022). Cox's proportional hazards regression model confirmed that expression of caspase-9 was the strongest prognostic factor in stage II colorectal cancer.

CONCLUSION

The mRNA expression of caspase-9 can be used as an independent prognostic factor for patients with stage II colorectal cancer.

Irbesartan treatment up-regulates hepatic expression of PPARalpha and its target genes in obese Koletsky (fa(k)/fa(k)) rats: a link to amelioration of hypertriglyceridaemia

BACKGROUND AND PURPOSE

Hypertriglyceridaemia is associated with an increased risk of cardiovascular disease. Irbesartan, a well-established angiotensin II type 1 receptor (AT(1)) blocker, improves hypertriglyceridaemia in rodents and humans but the underlying mechanism of action is unclear.

EXPERIMENTAL APPROACH

Male obese Koletsky (fa(k)/fa(k)) rats, which exhibit spontaneous hypertension and metabolic abnormalities, received irbesartan (40 mg x kg(-1) x day(-1)) or vehicle by oral gavage over 7 weeks. Adipocyte-derived hormones in plasma were measured by ELISA. Gene expression in liver and other tissues was assessed by real-time PCR and Western immunoblotting.

KEY RESULTS

In Koletsky (fa(k)/fa(k)) rats irbesartan lowered plasma concentrations of triglycerides and non-esterified fatty acids, and decreased plasma insulin concentrations and the homeostasis model assessment of insulin resistance index. However, this treatment did not affect food intake, body weight, epididymal white adipose tissue weight, adipocyte size and plasma leptin concentrations, although plasma adiponectin was decreased. Irbesartan up-regulated hepatic expression of mRNAs corresponding to peroxisome proliferator-activated receptor (PPAR)alpha and its target genes (carnitine palmitoyltransferase-1a, acyl-CoA oxidase and fatty acid translocase/CD36) that mediate hepatic fatty acid uptake and oxidation; the increase in hepatic PPARalpha expression was confirmed at the protein level. In contrast, irbesartan did not affect expression of adipose PPARgamma and its downstream genes or hepatic genes that mediate fatty acid synthesis.

CONCLUSIONS AND IMPLICATIONS

These findings demonstrate that irbesartan treatment up-regulates PPARalpha and several target genes in liver of obese spontaneously hypertensive Koletsky (fa(k)/fa(k)) rats and offers a novel insight into the lipid-lowering mechanism of irbesartan.