001-0 3 mg/kg/inj ) Blood samples were collected after test sess

001-0.3 mg/kg/inj.). Blood samples were collected after test sessions to determine 17 beta-estradiol levels. Banana-flavored food pellets were available on an FR 30 schedule in three

1-h sessions each day. Five monkeys were trained to discriminate cocaine (0.18 mg/kg, i.m.) from saline in a two-key food-reinforced procedure, and the effects of pretreatment with E-2 beta in cyclodextrin and in sesame oil were studied. Acute administration of E-2 beta did not consistently alter the cocaine self-administration or drug discrimination dose-effect curves in comparison to selleck inhibitor saline control treatment. Females also did not self-administer E-2 beta (0.00001-0.10 mg/kg, i.v.) above saline levels. Finally, E-2 beta (0.0001-0.01 mg/kg, i.m.) did not substitute for cocaine in monkeys trained to discriminate cocaine from saline. Taken together, these data suggest that over the dose range studied, estradiol administration does not consistently alter the abuse-related effects selleck screening library of cocaine in female rhesus monkeys.”
“Chronic exposure to cocaine is associated with neuroadaptions in stress and reward circuits that may increase susceptibility to relapse. We examined whether there are alterations in stress response and craving in abstinent cocaine-dependent individuals compared with a demographically matched group of non-addicted

socially drinking community controls. Forty treatment-engaged abstinent cocaine patients (17F/23M) and 40 controls (19F/21M) were exposed to a brief 5 min guided imagery of individually calibrated stressful situations, personal drug/alcohol-related

situation and a neutral-relaxing situation, one imagery per session, presented in random order. Craving, anxiety, emotion Fluocinolone acetonide rating scales, and physiological measures were assessed. Cocaine patients reported significantly higher and more persistent stress- and cue-induced drug/alcohol craving, negative emotions, and physiological responses compared with social drinkers. In cocaine patients, stress- and cue-induced drug craving was accompanied by increased anger, fear, sadness, heart rate, and SBP. Controls reported minimal stress- induced craving and only increases in anxiety and SBP during stress exposure. Cue-induced alcohol craving was accompanied only by an increase in relaxed state. Females reported increased stress- induced anxiety and sadness compared with males, while males were emotionally and physiologically more reactive in the cue condition. These findings are the first to document functional alterations in stress- and reward-related affect and physiology in recently abstinent cocaine patients that is marked by an enhanced sensitivity to stress- and drug-related cue exposure. These data suggest that recovery from chronic cocaine abuse could be hampered by a hyper-responsive stress- and drug-craving state that increases cocaine relapse susceptibility.

Data were collected from mTBI participants with PCS, mTBI partici

Data were collected from mTBI participants with PCS, mTBI participants without PCS and non-head-injured participants LY2874455 mouse (all groups: n=8). Magnetic resonance spectroscopy metabolite profiles within the dorsolateral prefrontal cortex showed a reduced creatine/choline ratio in mTBI patients compared with control participants. This data provides initial evidence for residual metabolic changes in chronic mTBI patients, but there was no conclusive relationship between these metabolic changes and PCS symptom report. Creatine is

involved in maintaining energy levels in cells with high or fluctuating energy demand, suggesting that there may be some residual energy impairment in chronic mTBI.”
“Self-assembly of Kaposi’s sarcoma-associated herpesvirus capsids occurs when six proteins are coexpressed in insect cells using recombinant baculoviruses; however, if the small capsid protein (SCP) is omitted from the coinfection, assembly does not

occur. Herein we delineate and identify precisely the assembly domain and the residues of SCP required for assembly. Hence, six residues, R14, D18, V25, R46, G66, and R70 in the assembly domain, when changed to alanine, completely abolish or reduce capsid assembly.”
“In a recent study, the association PCI-32765 solubility dmso between cardiovascular reactions to acute psychological stress and self-reported health was examined. Participants with excellent or good self-reported health exhibited higher cardiovascular reactivity than those who reported fair or poor health. We investigated this association in a population-based cohort of whom 725 men and women, aged 55-60 years, participated in a standardized psychological stress test. We measured continuous blood pressure and heart rate as well as cortisol reactivity. Good subjective health was associated with higher cardiovascular

and cortisol reactions to psychological stress. Results of the present study confirm those of the previously reported study showing that greater cardiovascular reactivity may not always be associated with negative health outcomes. In addition, the same holds for cortisol reactivity.”
“Unraveling the pathophysiological basis for the development of triclocarban and recovery from depression is a unique challenge. Dendritic plasticity has been reported to be involved in the development of depression. We modeled an anxiety/depression-like phenotype by chronic corticosterone exposure in mice and reversed this anxiety/depression-like phenotype by long-term treatment with fluoxetine (FLX). Spine density in the hippocampus was detected by Golgi-Cox staining at five time points. The data showed that 35 days of corticosterone exposure led to a decrease in spine density in CA1, concomitant with the onset of depression. Following 25 days of treatment with FLX, the decrease in both the dendritic spine density in the hippocampus and the anxiety/depression-like phenotype induced by chronic corticosterone recovered to normal levels concomitantly.

(c) 2008 Elsevier Ltd All rights reserved “
“Matrix (M) pro

(c) 2008 Elsevier Ltd. All rights reserved.”
“Matrix (M) protein mutants of vesicular stomatitis virus (VSV), such as rM51R-M virus, are less virulent than wild-type (wt) VSV strains due to their inability to

suppress innate immunity. Studies presented here show that when inoculated intranasally into mice, rM51R-M virus was cleared from nasal mucosa by day 2 postinfection and was attenuated for spread to the central nervous system, in contrast to wt VSV, thus accounting for its reduced virulence. However, it stimulated an antibody response similar to that in mice infected with the wt virus, indicating that it has the ability to induce adaptive immunity in vivo without causing disease. These results support the use of M protein mutants of VSV selleck chemicals Torin 1 manufacturer as vaccine vectors.”
“Ethanol exerts effects on the brain noradrenergic system, and these are thought to contribute to the sedative/hypnotic (depressant) effects of ethanol. Recent studies suggest that the norepinephrine transporter (NET) plays an important role in modulating ethanol’s depressant effects. The aim of the present study was to further characterize this role. Transporter blockers with varying affinity for NET versus the serotonin

transporter (desipramine > fluoxetine > citalopram) were tested for their ability to alter ethanol’s depressant effects, and for comparison, hypothermic effects. Effects of desipramine on another depressant, pentobarbital, were examined. Desipramine potentiation of ethanol’s depressant effects was assessed following depletion of brain

norepinephrine via N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride (DSPA) treatment, or depletion of brain 5-HT via para-chlorophenylalanine methyl ester hydrochloride (PCPA) treatment. The effects of co-administration of either the selective alpha 2-adrenoreceptor agonist (dexmedetomidine) or the selective alpha 2-adrenoreceptor antagonist (atipamezole) on desipramine’s effect on ethanol’s depressant effects were examined. Given the close link between stress, ethanol and norepinephrine, desipramine potentiation of ethanol’s depressant effects was tested following repeated forced swim stress. Results showed that desipramine, but not SERT-selective doses of citalopram or fluoxetine, strongly potentiated the depressant (not hypothermic) effects of ethanol. These effects were mimicked by dexmedetomidine Glycogen branching enzyme and blocked by atipamezole, but not by depletion of either norepinephrine or 5-HT. Desipramine potentiation of ethanol’s depressant effects was abolished following repeated stress. Present findings further support a major role for NET and the alpha 2-adrenoreceptor in modulating the depressant effects of ethanol, with possible implications for understanding the role of noradrenergic dysfunction in stress-related alcoholism. Published by Elsevier Ltd.”
“VP22, encoded by the UL49 gene of Marek’s disease virus (MDV), is indispensable for virus cell-to-cell spreading.

Moreover, vIRF-3 is known

Moreover, vIRF-3 is known learn more to be involved in modulation of the type I interferon (IFN) response. We now show that vIRF-3 also interferes with the type II interferon

system and antigen presentation to the adaptive immune system. Starting with an analysis of the transcriptome, we show that vIRF-3 inhibits expression of major histocompatibility complex class II (MHC II) molecules: small interfering RNA (siRNA)-mediated knockdown of vIRF-3 in KSHV-infected PEL cell lines resulted in increased MHC II levels; overexpression of vIRF-3 in KSHV-negative B cells leads to downmodulation of MHC II. This regulation could be traced back to inhibition of class II transactivator (CIITA) transcription by vIRF-3. Reporter assays revealed that the gamma interferon (IFN-gamma)-sensitive CIITA promoters PIV and PIII were inhibited by vIRF-3. Consistently, IFN-gamma levels increased upon vIRF-3 knockdown in PEL cells. IFN-gamma regulation by vIRF-3 was confirmed in reporter assays as well as by upregulation of typical IFN-gamma target genes upon knockdown of vIRF-3 in PEL cells. Microtubule Associated inhibitor In summary, we conclude that vIRF-3 contributes to the viral immunoevasion by downregulation of IFN-gamma and CIITA and thus MHC II expression.”
“Distinct visual pathways are selectively tuned for processing

specific spatial frequencies. Recently, Awasthi, Friedman, and Williams (2011) reported fast categorisation of faces at periphery, arguing for primacy of low spatial frequency SB-3CT (LSF) information in face processing. However, previous studies have also documented rapid categorization of places and natural scenes. Here, we tested if the LSF advantage is face specific or also involved in place perception. We used visually guided reaching as a continuous behavioral measure to examine the processing of LSF and high spatial frequency (HSF) hybrids, presented at the periphery. Subjects reached out and touched targets and their movements were recorded. The trajectories revealed that LSF interference

was both 95 ms earlier and stronger for faces than places and was lateralized to the left visual field. The early processing of LSF information supports the assumption that faces are prioritised and provides a (neural) framework for such specialised processing. (C) 2011 Elsevier Ltd. All rights reserved.”
“The prion agent is the infectious particle causing spongiform encephalopathies in animals and humans and is thought to consist of an altered conformation (PrPSc) of the normal and ubiquitous prion protein PrPC. The interaction of the prion agent with the immune system, particularly the humoral immune response, has remained unresolved. Here we investigated the immunogenicity of full-length native and infectious prions, as well as the specific biological effects of the resulting monoclonal antibodies (MAbs) on the binding and clearance of prions in cell culture and in in vivo therapy.

43 (p=0) to $1 14 (p=0) However,

43 (p=0) to $1.14 (p=0). However, click here DAH to the non-governmental

sector had a positive and significant effect on domestic government health spending. Both results were robust to multiple specifications and subset analyses. Other factors, such as debt relief, had no detectable effect on domestic government health spending.

Interpretation To address the negative effect of DAH on domestic government health spending, we recommend strong standardised monitoring of government health expenditures and government spending in other health-related sectors; establishment of collaborative targets to maintain or increase the share of government expenditures going to health; investment in the capacity of developing countries to effectively receive and use DAH; careful assessment of the risks and benefits of expanded DAH to non-governmental sectors; and investigation of the use of global price subsidies or product transfers as mechanisms for DAH.”
“Prenatal exposure to morphine

can alter the capacities for learning and memory and the sensitivity to drugs of abuse in progeny. In the present study, we examined the effects of morphine during chick embryonic period of 5-8, 9-12, 13-16 and U0126 supplier 17-20 on cognitive function and the sensitivities to morphine reward in the post-hatch chick, using the one-trial passive avoidance learning task and the conditioned place preference paradigm. It was observed that the injection of morphine (1 mg/kg of egg weight) during E5-8, but not in other three periods, significantly impaired intermediate- and long-term memory in one-day-old chicks. On the other hand, the chicks prenatally exposed to morphine during E17-20 remarkably not only acquired but also maintained the conditioned place preference induced by morphine. The present results suggest that there are two time-windows during development, which in the chick are around E5-8 and E17-20, when prenatal morphine exposure is likely to confer maximal risks

Diflunisal for vulnerabilities to breakdown of memory consolidation and to morphine-induced reward in day-old chicks respectively. (C) 2010 Elsevier Ireland Ltd. All rights reserved.”
“Chagas disease is a chronic, systemic, parasitic infection caused by the protozoan Trypanosoma cruzi, and was discovered in 1909. The disease affects about 8 million people in Latin America, of whom 30-40% either have or will develop cardiomyopathy, digestive megasyndromes, or both. In the past three decades, the control and management of Chagas disease has undergone several improvements. Large-scale vector control programmes and screening of blood donors have reduced disease incidence and prevalence.

The application of unpaired and extinction control procedures dem

The application of unpaired and extinction control procedures demonstrated that also in teleosts www.selleckchem.com/products/Dasatinib.html the learning of this motor response depends on associative rules. In Experiment 2 we studied whether classical conditioning of this response is critically dependent on the cerebellum and independent

of telencephalic structures as occurs in mammals. Cerebellum lesion prevented the acquisition of the eyeblink-like conditioned response whereas telencephalon ablation did not impair the learning of this response. No deficit was observed following lesions in the performance of the unconditioned response or in the percentage of spontaneous responses. These results suggest that cerebellum ablation in goldfish affects a critical component of the circuitry necessary for the acquisition of the conditioned response but does not interfere with the ability

of the animal to perform the response itself. The striking similarity in the role of cerebellum in classical conditioning of a motor response between teleost fish and mammals suggests that this learning function of the cerebellum could be a primitive feature of the vertebrate brain that has been conserved through evolution. (C) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.”
“How many generations XMU-MP-1 ago did the common ancestor of all present-day individuals live, and how does inbreeding affect this estimate? The number of ancestors within family trees determines the timing of the most recent common ancestor of humanity. However, mating is often non-random and inbreeding is ubiquitous in natural populations. Rates of pedigree growth are found for multiple types of inbreeding. This data is then combined with models from of global population structure to estimate biparental coalescence times. When pedigrees for regular systems of mating are constructed, the growth rates of inbred populations contain Fibonacci n-step constants. The timing of the most recent common ancestor depends

on global population structure, the mean rate of pedigree growth, mean fitness, and current population size. Inbreeding reduces the number of ancestors in a pedigree, pushing back global common ancestry times. These results are consistent with the remarkable findings of previous studies: all humanity shares common ancestry in the recent past. (C) 2009 Elsevier Ltd. All rights reserved.”
“Mice provide a highly valuable resource for investigating learning and memory processes; however, many of the established tasks for evaluating learning and memory were developed for rats. Behaviors of mice in these tasks appear to be driven by different motivational factors, and as a result, they often do not perform reliably on tasks involving rewards traditionally used for rats.

1038/labinvest 2009 82; published online 3 August 2009″
“One

1038/labinvest.2009.82; published online 3 August 2009″
“One difficulty in studying dengue virus (DENV) is the lack of an experimental model that reproduces the human disease. In a previous work, we have shown that BALB/c mice intraperitoneally inoculated with a DENV-2 isolate presented viremia and mild focal areas

of liver injuries. In this study, mice were inoculated by the intravenous route and presented extensive damage areas in the liver tissue, which were evaluated by histopathological and ultrastructural analysis. Hepatic injury was noted mainly around the central vein and portal tracts. Damages consist of hepatocyte injury, including steatosis, swelling and necrosis. Further, erythrophagocytosis, selleck compound intercellular edema and vascular damages were evident, including hemorrhage, which is characteristic of the dengue-induced hepatitis in human liver. Hepatic lesions were already noted 2 days post infection (p.i.), although effects were more extensive after the seventh day p.i. An increase in alanine aminotransferase and aspartate aminotransferase serum levels was detected 7 and 14 days p.i., respectively, and had correlation Selinexor to hepatic lesions. Alterations caused by the DENV infection were self-limiting, with a remarkable reduction of all liver damages 49 days p.i. Virus antigens were detected in hepatocytes, Kupffer cells and vascular endothelium,

suggesting virus replication in these cells. In situ hybridization, using a probe that anneals in the virus negative RNA strand, showed positive reaction in hepatocytes and vascular endothelium cells of infected mice, thus confirming virus replication in such cells. In general, ASK1 results revealed

that this mouse model reproduces some histopathological effects observed in humans and supports previous findings indicating virus replication in the hepatic tissue. Laboratory Investigation (2009) 89, 1140-1151; doi:10.1038/labinvest.2009.83; published online 31 August 2009″
“This study evaluates the intra- and inter-subject variability of digit maps in area 3b of anesthetized squirrel monkeys. Maps were collected using high field blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI). BOLD responses to individual digit stimulations were mapped and their response properties (location, area of activation, % signal change, time to peak response) were compared within and across imaging sessions separated by up to 20 months. During single digit stimulation using a block design, the spatiotemporal response of the BOLD signal for individual runs within and across sessions and animals was well conserved, with a time to peak BOLD response of 20 +/- 4 s. The variability in the center of BOLD activation in area 3b was 0.41 +/- 0.24 mm (mean +/- SD) across individual 5-7 min runs within a scanning session and 0.55 +/- 0.15 mm across sessions. The average signal change across all animals, runs and sessions was 0.62 +/- 0.38%, and varied 32% within and 40% across sessions.

Results: Subclavian artery stenosis, with or without poststenotic

Results: Subclavian artery stenosis, with or without poststenotic dilatation (PSD), was found in 26 patients (63%), subclavian artery aneurysms in 12 (29%), chronic subclavian occlusion in 1(2.4%), and axillary artery compression in 2 (5%). Chronic symptoms difficult to discern from neurogenic compression were present in 27 patients (66%; 24 had subclavian stenoses or PSD, or both, 1 had subclavian occlusion, and 2 had axillary artery compression);

13 (32%) presented with acute ischemia (11 had aneurysms and 2 had PSDs), and 1 asymptomatic patient had a subclavian aneurysm. Osteoarticular anomalies were found in 27 patients (66%), including 19 cervical ribs, 4 first rib anomalies, and 4 clavicular or first rib fractures, or both. Among 27 patients with subclavian aneurysms or PSD, 21 (78%) had a bone anomaly. Arterial pathology was deemed significant buy BMS202 in 30 patients (73%) and mild or moderate in 11 (21%). Symptoms in 23 of these patients were compatible with neurogenic compression without clinical suspicion of arterial pathology, but 13 (56%) harbored a significant arterial anomaly.

Conclusions: The incidence of arterial pathology secondary to compression at the TO may be underestimated, and in the absence of obvious ischemia, significant arterial pathology may not be suspected. Two-thirds

of patients with arterial compression have associated bone anomalies. Therefore, routine arterial imaging seems advisable for patients evaluated for TO syndrome in the presence of a bone anomaly at the TO or an examination that shows an arterial abnormality. LY2090314 in vivo In the absence of these signs, however, arterial pathology may be overlooked in patients with symptoms suggestive of neurogenic compression. Further study is needed to elucidate the incidence, natural history, and clinical relevance of arterial compression and PSD at the TO. (J Vasc Surg 2010;52:406-11.)”
“Background: Mineralocorticoid antagonists improve survival among patients with PDK4 chronic, severe systolic

heart failure and heart failure after myocardial infarction. We evaluated the effects of eplerenone in patients with chronic systolic heart failure and mild symptoms.

Methods: In this randomized, double-blind trial, we randomly assigned 2737 patients with New York Heart Association class II heart failure and an ejection fraction of no more than 35% to receive eplerenone (up to 50 mg daily) or placebo, in addition to recommended therapy. The primary outcome was a composite of death from cardiovascular causes or hospitalization for heart failure.

Results: The trial was stopped prematurely, according to prespecified rules, after a median follow-up period of 21 months. The primary outcome occurred in 18.3% of patients in the eplerenone group as compared with 25.9% in the placebo group (hazard ratio, 0.

7 seconds

Conclusions: The study shows that patient c

7 seconds.

Conclusions: The study shows that patient controlled genital nerve stimulation is as effective as automatic controlled stimulation to treat neurogenic detrusor overactivity. Thus, patient controlled stimulation is feasible in select patients, although patients must be trained in the technique.”
“Acquisition

of drug-reinforced behavior is accompanied by a systematic increase of release of the neurotransmitter acetylcholine (ACh) rather than dopamine, the expected prime reward neurotransmitter candidate, in the nucleus accumbens core ( AcbC), with activation of both muscarinic and nicotinic ACh receptors in the AcbC by ACh volume transmission being necessary for the drug conditioning. The present findings suggest that the selleck chemicals AcbC ACh system is preferentially activated by drug reinforcers, because ( 1) acquisition of food-reinforced

behavior was not paralleled by activation of ACh release in the AcbC whereas acquisition of morphine-reinforced behavior, like that of cocaine or remifentanil ( tested previously), was, and because ( 2) local intra-AcbC administration of muscarinic or nicotinic ACh receptor antagonists ( atropine or mecamylamine, respectively) did not block the acquisition of food-reinforced behavior whereas acquisition of drug-reinforced behavior had been blocked. Interestingly, the speed with which a drug of abuse distributed into the AcbC and was eliminated from the AcbC determined the size of the AcbC ACh signal, with AP26113 mw the temporally more sharply delineated drug stimulus producing a more pronounced AcbC ACh signal. The present findings suggest

that muscarinic and nicotinic ACh receptors in the AcbC are preferentially involved during reward conditioning for drugs of abuse vs sweetened condensed milk as a food reinforcer.”
“Purpose: In patients with U0126 supplier solid organ transplants urethral strictures may develop from repeat catheterization, recurrent urinary tract infection or chronic irritation of the urethral mucosa secondary to contact with pancreatic enzymes. We describe surgical outcomes in patients with kidney and kidney-pancreas transplants after urethral reconstruction for stricture or fistula disease.

Materials and Methods: Ten males underwent urethroplasty for urethral stricture (9) or urethral fistula (1) disease after kidney or kidney-pancreas transplantation. Median patient age was 41.5 years (range 25 to 56) and average time from transplantation was 9 years (range 1 to 14). Four patients underwent bulbar urethroplasty with buccal mucosa, 3 underwent stricture excision and primary anastomosis of the bulbar urethra, 2 underwent penile urethroplasty with graft tissue and I underwent bulbar urethrocutaneous fistula repair.

Results: The etiology of stricture disease was pancreatic enzyme induced stricture in 40% of cases, catheter trauma in 40% and unknown in 20%.

Analyses using recombinant

Analyses using recombinant PD173074 MVs with chimeric genomes

between wild- type and Edmonston vaccine strains indicated that viruses possessing the polymerase protein genes of the Edmonston strain exhibited attenuated viral gene expression and growth in cultured cells as well as in mice expressing an MV receptor, signaling lymphocyte activation molecule, regardless of whether the virus genome had the wild-type or vaccine-type promoter sequence. These data demonstrate that the polymerase protein genes of the Edmonston strain contribute to its attenuated phenotype.”
“Thermal messages are relayed to the medial preoptic O-anterior hypothalamus (mPOAH) via the ascending reticular activating system (ARAS). According to previous findings that norepinephrine (NE)-ergic and GABA (gamma-amino butyric acid)-ergic inputs convey thermal information to the CNS, those neurotransmitters may be responsible for reciprocal correlation between body temperature and mPOAH warm-(WSNs) and cold-(CSNs) sensitive neuronal firing rates for thermoregulation. In this study on Wistar rats, we have characterized in vivo the role of alpha-1 NE-ergic and GABA-A receptors in the possible

modulation of ARAS inputs to the thermosensitive neurons in the mPOAH. Nine WSNs, 7 CSNs and 19 thermo-insensitive neurons were recorded from mPOAH and effects of ARAS stimulation and iontophoretic application of prazosin as AG-014699 supplier well as picrotoxin on those neurons were HSP90 evaluated. The WSNs were excited by ARAS stimulation but inhibited by both prazosin and picrotoxin; whereas the CSNs were inhibited by ARAS stimulation and prazosin, but excited by picrotoxin. The NE excited the WSNs as well as the CSNs, while GABA had opposite effects on them, suggesting that NE and GABA interact in the mPOAH for thermoregulation. The findings unravel an intriguing possibility that in the mPOAH, GABA simultaneously acts on hetero-receptors located at pre-and post-synaptic sites, modulating the release of NE on the WSNs and CSNs for thermoregulation. Further, ARAS stimulation-induced similar excitatory and inhibitory responses of the WSNs and the CSNs support such converging inputs on these neurons

for thermoregulation. (c) 2009 IBRO. Published by Elsevier Ltd. All rights reserved.”
“Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) is known to take an endosomal pathway for cell entry; however, it is thought to enter directly from the cell surface when a receptor-bound virion spike (S) protein is affected by trypsin, which induces cleavage of the S protein and activates its fusion potential. This suggests that SARS-CoV bearing a cleaved form of the S protein can enter cells directly from the cell surface without trypsin treatment. To explore this possibility, we introduced a furin-like cleavage sequence in the S protein at amino acids 798 to 801 and found that the mutated S protein was cleaved and induced cell fusion without trypsin treatment when expressed on the cell surface.