In ovo administration of a phage cocktail partially prevents colibacillosis in chicks

Avian pathogenic Escherichia coli (APEC) causes colibacillosis, the main bacterial disease in poultry leading to significant economic losses worldwide. Antibiotic treatments favor the emergence of multidrug-resistant bacteria, and preventive measures are insufficient to control the disease. There is increasing interest in using the potential of bacteriophages, not only for phage therapy but also for prevention and biocontrol. This study aimed to evaluate the efficacy of a phage cocktail administered in ovo to prevent avian colibacillosis in chicks. When 4 different phages (REC, ESCO3, ESCO47, and ESCO58), stable under avian physiological conditions, were combined and inoculated at 17 embryogenic days (ED), they were transmitted to the newly hatched chicks. In a second trial, the 4-phage cocktail was inoculated into the allantoic fluid at ED16 and after hatch 1-day-old chicks were challenged with the O2 APEC strain BEN4358 inoculated subcutaneously. Two phages (REC and ESCO3) were still detected in the ceca of surviving chicks at the end of the experiment (7-days postinfection). Chicks that received the phages in ovo did not develop colibacillosis lesions and showed a significant decrease in intestinal BEN4358 load (8.00 × 107 CFU/g) compared to the challenged chicks (4.52 × 108 CFU/g). The majority of the reisolated bacteria from the ceca of surviving chicks had developed full resistance to ESCO3 phage, and only 3 were resistant to REC phage. The partially or complete resistance of REC phage induced a considerable cost to bacterial virulence. Here, we showed that phages inoculated in ovo can partially prevent colibacillosis in 1-wk-old chicks. The reduction in the APEC load in the gut and the decreased virulence of some resistant isolates could also contribute to control the disease.

PFAS levels and determinants of variability in exposure in European teenagers - Results from the HBM4EU aligned studies (2014-2021)

BACKGROUND

Perfluoroalkyl substances (PFAS) are man-made fluorinated chemicals, widely used in various types of consumer products, resulting in their omnipresence in human populations. The aim of this study was to describe current PFAS levels in European teenagers and to investigate the determinants of serum/plasma concentrations in this specific age group.

METHODS

PFAS concentrations were determined in serum or plasma samples from 1957 teenagers (12-18 years) from 9 European countries as part of the HBM4EU aligned studies (2014-2021). Questionnaire data were post-harmonized by each study and quality checked centrally. Only PFAS with an overall quantification frequency of at least 60% (PFOS, PFOA, PFHxS and PFNA) were included in the analyses. Sociodemographic and lifestyle factors were analysed together with food consumption frequencies to identify determinants of PFAS exposure. The variables study, sex and the highest educational level of household were included as fixed factors in the multivariable linear regression models for all PFAS and each dietary variable was added to the fixed model one by one and for each PFAS separately.

RESULTS

The European exposure values for PFAS were reported as geometric means with 95% confidence intervals (CI): PFOS [2.13 μg/L (1.63-2.78)], PFOA ([0.97 μg/L (0.75-1.26)]), PFNA [0.30 μg/L (0.19-0.45)] and PFHxS [0.41 μg/L (0.33-0.52)]. The estimated geometric mean exposure levels were significantly higher in the North and West versus the South and East of Europe. Boys had significantly higher concentrations of the four PFAS compared to girls and significantly higher PFASs concentrations were found in teenagers from households with a higher education level. Consumption of seafood and fish at least 2 times per week was significantly associated with 21% (95% CI: 12-31%) increase in PFOS concentrations and 20% (95% CI: 10-31%) increase in PFNA concentrations as compared to less frequent consumption of seafood and fish. The same trend was observed for PFOA and PFHxS but not statistically significant. Consumption of eggs at least 2 times per week was associated with 11% (95% CI: 2-22%) and 14% (95% CI: 2-27%) increase in PFOS and PFNA concentrations, respectively, as compared to less frequent consumption of eggs. Significantly higher PFOS concentrations were observed for participants consuming offal (14% (95% CI: 3-26%)), the same trend was observed for the other PFAS but not statistically significant. Local food consumption at least 2 times per week was associated with 40% (95% CI: 19-64%) increase in PFOS levels as compared to those consuming local food less frequently.

CONCLUSION

This work provides information about current levels of PFAS in European teenagers and potential dietary sources of exposure to PFAS in European teenagers. These results can be of use for targeted monitoring of PFAS in food.

Approaches to mixture risk assessment of PFASs in the European population based on human hazard and biomonitoring data

Per- and polyfluoroalkyl substances (PFASs) are a highly persistent, mobile, and bioaccumulative class of chemicals, of which emissions into the environment result in long-lasting contamination with high probability for causing adverse effects to human health and the environment. Within the European Biomonitoring Initiative HBM4EU, samples and data were collected in a harmonized way from human biomonitoring (HBM) studies in Europe to derive current exposure data across a geographic spread. We performed mixture risk assessments based on recent internal exposure data of PFASs in European teenagers generated in the HBM4EU Aligned Studies (dataset with N = 1957, sampling years 2014-2021). Mixture risk assessments were performed based on three hazard-based approaches: the Hazard Index (HI) approach, the sum value approach as used by the European Food Safety Authority (EFSA) and the Relative Potency Factor (RPF) approach. The HI approach resulted in the highest risk estimates, followed by the RPF approach and the sum value approach. The assessments indicate that PFAS exposure may result in a health risk in a considerable fraction of individuals in the HBM4EU teenager study sample, thereby confirming the conclusion drawn in the recent EFSA scientific opinion. This study underlines that HBM data are of added value in assessing the health risks of aggregate and cumulative exposure to PFASs, as such data are able to reflect exposure from different sources and via different routes.

Evaluation of ferrocenyl-containing γ-hydroxy-γ-lactam-derived tetramates as potential antiplasmodials

A series of ferrocenyl-containing γ-hydroxy-γ-lactam tetramates were prepared in 2-3 steps through ring opening-ring closure (RORC) process of γ-ylidene-tetronate derivatives in the presence of ferrocenyl alkylamines. The compounds were screened in vitro for their antiplasmodial activity against chloroquine-sensitive (3D7) and chloroquine-resistant (W2) clones of P. falciparum, displaying activity in the range of 0.12-100 μM, with generally good resistance index. The most active ferrocene in these series exhibited IC₅₀ equal to 0.09 μM (3D7) and 0.12 μM (W2). The low cytotoxicity of the ferrocenyl-containing γ-hydroxy-γ-lactam tetramates against Human Umbilical Vein Endothelial (HUVEC) cell line demonstrated selective antiparasitic activity. The redox properties of these ferrocene-derived tetramates were studied and physico-biochemical studies evidenced that these derivatives can exert potent antimalarial activities via a mechanism distinct from ferroquine.

Airway Administration of Flagellin Regulates the Inflammatory Response to Pseudomonas aeruginosa

Excessive lung inflammation and airway epithelial damage are hallmarks of human inflammatory lung diseases, such as cystic fibrosis (CF). Enhancement of innate immunity provides protection against pathogens while reducing lung-damaging inflammation. However, the mechanisms underlying innate immunity–mediated protection in the lung remain mysterious, in part because of the lack of appropriate animal models for these human diseases. TLR5 (Toll-like receptor 5) stimulation by its specific ligand, the bacterial protein flagellin, has been proposed to enhance protection against several respiratory infectious diseases, although other cellular events, such as calcium signaling, may also control the intensity of the innate immune response. Here, we investigated the molecular events prompted by stimulation with flagellin and its role in regulating innate immunity in the lung of the pig, which is anatomically and genetically more similar to humans than rodent models. We found that flagellin treatment modulated NF-κB signaling and intracellular calcium homeostasis in airway epithelial cells. Flagellin pretreatment reduced the NF-κB nuclear translocation and the expression of proinflammatory cytokines to a second flagellin stimulus as well as to Pseudomonas aeruginosa infection. Moreover, in vivo administration of flagellin decreased the severity of P. aeruginosa–induced pneumonia. Then we confirmed these beneficial effects of flagellin in a pathological model of CF by using ex vivo precision-cut lung slices from a CF pigz model. These results provide evidence that flagellin treatment contributes to a better regulation of the inflammatory response in inflammatory lung diseases such as CF.

Severe pulmonary arterial hypertension and massive ascites in a patient with systemic lupus erythematosus and secondary Sjogren's syndrome

BACKGROUND

Pulmonary arterial hypertension (PAH), is a rare manifestation of systemic lupus erythematosus (SLE), characterized by pulmonary arterial remodeling leading to right ventricular failure and death. To date, optimal management of SLE-associated PAH should be clarified, especially regarding the respective places of immunosuppressants and PAH vasodilator treatments.

CASE REPORT

We report the case of a 48-year-old woman with SLE and secondary Sjogren syndrome, associated with severe PAH and lupus peritonitis with massive ascites, who showed a remarkable response, both for SLE flare and PAH, to a treatment combining immunosuppressants and pulmonary arterial vasodilator treatment.

CONCLUSION

This observation highlights the interest of combining immunosuppressive therapy in SLE-PAH, whose modalities in association with PAH treatments should be clarified.

Acute Cardiac Failure Due to Takotsubo Cardiomyopathy Secondary to a Phone Call for Lung Transplantation: A Case Report

Lung transplantation is a therapeutic option for certain end-stage lung diseases. The phone call for lung transplantation is a major event in the life of these patients; as a result, it can generate significant stress. We herein present the case of a 58-year-old female patient with end-stage chronic obstructive pulmonary disease (COPD) who, while on the lung transplantation waiting list, received such a call. Complete transplant work-up, including cardiac tests undertaken shortly before, had revealed no contraindication to lung transplantation. She was admitted with severe acute respiratory failure, and her extensive work-up was compatible with pulmonary edema due to takotsubo cardiomyopathy. The lung transplantation was thus cancelled, owing to the patient's health condition and the poor quality of the graft as well. The patient stayed in the intensive care unit for several days, requiring noninvasive ventilation. The left ventricular function recovered completely within 10 days postdiagnosis, and the patient was discharged 13 days after her admission. The patient was transplanted 1 month thereafter, without any particular problems; she is currently, 8 months post-transplantation, in good condition. In the given case, the call for lung transplantation could have generated emotional stress severe enough to lead to takotsubo cardiomyopathy.

Temporal pattern recognition with delayed feedback spin-torque nano-oscillators

The recent demonstration of neuromorphic computing with spin-torque nano-oscillators has opened a path to energy efficient data processing. The success of this demonstration hinged on the intrinsic short-term memory of the oscillators. In this study, we extend the memory of the spin-torque nano-oscillators through time-delayed feedback. We leverage this extrinsic memory to increase the efficiency of solving pattern recognition tasks that require memory to discriminate different inputs. The large tunability of these non-linear oscillators allows us to control and optimize the delayed feedback memory using different operating conditions of applied current and magnetic field.

Host factors determine the evolution of infection with Staphylococcus aureus to gangrenous mastitis in goats

Staphylococcus aureus is the major cause of very severe mastitis of dairy goats. The initial objective of our study was to fine-tune an experimental model of infection of the goat mammary gland with two strains of S. aureus and two lines of goats (low and high somatic cell score lines). Following the challenge, the 10 infected goats divided in two clear-cut severity groups, independently of the S. aureus strain and the goat line. Five goats developed very severe mastitis (of which four were gangrenous) characterized by uncontrolled infection (UI group), whereas the other five kept the infection under control (CI group). The outcome of the infection was determined by 18 h post-infection (hpi), as heralded by the bacterial milk concentration at 18 hpi: more than 10⁷/mL in the UI group, about 10⁶/mL in the CI group. Leukocyte recruitment and composition did not differ between the groups, but the phagocytic killing at 18 hpi efficiency did. Contributing factors involved milk concentrations of α-toxin and LukMF′ leukotoxin, but not early expression of the genes encoding the pentraxin PTX3, the cytokines IL-1α and IL-1β, and the chemokines IL-8 and CCL5. Concentrations of TNF-α, IFN-γ, IL-17A, and IL-22 rose sharply in the milk of UI goats when infection was out of control. The results indicate that defenses mobilized by the mammary gland at an early stage of infection were essential to prevent staphylococci from reaching critical concentrations. Staphylococcal exotoxin production appeared to be a consequent event inducing the evolution to gangrenous mastitis.

Neuromorphic Computing through Time-Multiplexing with a Spin-Torque Nano-Oscillator

Fabricating powerful neuromorphic chips the size of a thumb requires miniaturizing their basic units: synapses and neurons. The challenge for neurons is to scale them down to submicrometer diameters while maintaining the properties that allow for reliable information processing: high signal to noise ratio, endurance, stability, reproducibility. In this work, we show that compact spin-torque nano-oscillators can naturally implement such neurons, and quantify their ability to realize an actual cognitive task. In particular, we show that they can naturally implement reservoir computing with high performance and detail the recipes for this capability.

Schmallenberg virus: experimental infection in goats and bucks

Background

Schmallenberg virus (SBV) is an emerging Orthobunyavirus of ruminant livestock species currently circulating in Europe. SBV causes a subclinical or mild disease in adult animals but vertical transmission to pregnant dams may lead to severe malformations in the offspring. Data on the onset of clinical signs, viremia and seroconversion in experimentally infected adult animals are available for cattle and sheep but are still lacking for goats.

For a better understanding of the pathogenesis of SBV infection in adult ruminants, we carried out experimental infections in adult goats. Our specific objectives were: (i) to record clinical signs, viremia and seroconversion; (ii) to monitor viral excretion in the semen of infected bucks; (iii) to determine in which tissues SBV replication took place and virus-induced lesions developed.

Results

Four goats and two bucks were inoculated with SBV. Virus inoculation was followed by a short viremic phase lasting 3 to 4 days and a seroconversion occurring between days 7 and 14 pi in all animals. The inoculated goats did not display any clinical signs, gross lesions or histological lesions. Viral genomic RNA was found in one ovary but could not be detected in other organs. SBV RNA was not found in the semen samples collected from two inoculated bucks.

Conclusions

In the four goats and two bucks, the kinetics of viremia and seroconversion appeared similar to those previously described for sheep and cattle. Our limited set of data provides no evidence of viral excretion in buck semen.

Epizootic hemorrhagic disease virus serotype 6 experimentation on adult cattle

Epizootic hemorrhagic disease virus (EHDV), an arthropod-borne orbivirus (family Reoviridae), is an emerging pathogen of wild and domestic ruminants closely related to bluetongue virus (BTV). EHDV serotype 6 (EHDV6) has recently caused outbreaks close to Europe in Turkey and Morocco and a recent experimental study performed on calves inoculated with these two EHDV6 strains showed that the young animals have remained clinically unaffected. The aim of this study was to investigate the pathogenicity of an EHDV6 strain from La Reunion Island in adult Holstein (18-month-old heifers). This EHDV6 strain has induced clinical signs in cattle in the field. Samples taken throughout the study were tested with commercially available ELISA and real-time RT-PCR kits. Very mild clinical manifestations were observed in cattle during the experiment although high levels of viral RNA and virus were found in their blood. EHDV was isolated from the blood of infected animals at 8 dpi. Antibodies against EHDV were first detected by 7 dpi and persisted up to the end of the study. Virus was detected in various tissue samples until 35 dpi, but was not infectious. In view of the recent circulation of different arboviruses in Europe, this study demonstrates what the EHD induces a strong viraemia in adult Holstein cattle and shows that a spread of EHD on European livestock cattle is possible.

Schmallenberg virus experimental infection of sheep

Since late 2011, a novel orthobunyavirus, named Schmallenberg virus (SBV), has been implicated in many cases of severely malformed bovine and ovine offspring in Europe. In adult cattle, SBV is known to cause a mild transient disease; clinical signs include short febrile episodes, decreased milk production and diarrhoea for a few days. However, the knowledge about clinical signs and pathogenesis in adult sheep is limited. In the present study, adult sheep of European domestic breeds were inoculated with SBV either as cell culture grown virus or as virus with no history of passage in cell cultures. Various experimental set-ups were used. Sampling included blood collection at different time points during the experimental period and selected organ material at autopsy. Data from this study showed, that the RNAemic period in sheep was as short as reported for cattle; viral genome was detectable for about 3-5 days by real-time RT-PCR. In total, 13 out of 30 inoculated sheep became RNAemic, with the highest viral load in animals inoculated with virus from low cell culture passaged or the animal passaged material. Contact animals remained negative throughout the study. One RNAemic sheep showed diarrhoea for several days, but fever was not recorded in any of the animals. Antibodies were first detectable 10-14 days post inoculation. Viral RNA was detectable in spleen and lymph nodes up to day 44 post inoculation. In conclusion, as described for cattle, SBV-infection in adult sheep predominantly results in subclinical infection, transient RNAemia and a specific antibody response. Maintenance of viral RNA in the lymphoreticular system is observed for an extended period.

Host-seeking activity of bluetongue virus vectors: endo/exophagy and circadian rhythm of Culicoides in Western Europe

Feeding success of free-living hematophagous insects depends on their ability to be active when hosts are available and to reach places where hosts are accessible. When the hematophagous insect is a vector of pathogens, determining the components of host-seeking behavior is of primary interest for the assessment of transmission risk. Our aim was to describe endo/exophagy and circadian host-seeking activity of Palaearctic Culicoides species, which are major biting pests and arbovirus vectors, using drop traps and suction traps baited with four sheep, as bluetongue virus hosts. Collections were carried out in the field, a largely-open stable and an enclosed stable during six collection periods of 24 hours in April/May, in late June and in September/October 2010 in western France. A total of 986 Culicoides belonging to 13 species, mainly C. brunnicans and C. obsoletus, was collected on animal baits. Culicoides brunnicans was clearly exophagic, whereas C. obsoletus was able to enter stables. Culicoides brunnicans exhibited a bimodal pattern of host-seeking activity with peaks just after sunrise and sunset. Culicoides obsoletus was active before sunset in spring and autumn and after sunset in summer, thus illustrating influence of other parameters than light, especially temperature. Description of host-seeking behaviors allowed us to discuss control strategies for transmission of Culicoides-borne pathogens, such as bluetongue virus. However, practical vector-control recommendations are difficult to provide because of the variation in the degree of endophagy and time of host-seeking activity.

Synthesis and antimicrobial evaluation of amphiphilic neamine derivatives

The aminoglycoside antibiotics bind to the 16S bacterial rRNA and disturb the protein synthesis. One to four hydroxyl functions of the small aminoglycoside neamine were capped with phenyl, naphthyl, pyridyl, or quinolyl rings. The 3',4'- (6), 3',6- (7a), and the 3',4',6- (10a) 2-naphthylmethylene derivatives appeared to be active against sensitive and resistant Staphylococcus aureus strains. 10a also showed marked antibacterial activities against Gram (-) bacteria, including strains expressing enzymes modifying aminoglycosides, efflux pumps, or rRNA methylases. 7a and 10a revealed a weak and aspecific binding to a model bacterial 16S rRNA. Moreover, as compared to neomycin B, 10a showed a lower ability to decrease (3)H leucine incorporation into proteins in Pseudomonas aeruginosa. All together, our results suggest that the 3',4',6-tri-2-naphthylmethylene neamine derivative 10a should act against Gram (-) bacteria through a mechanism different from inhibition of protein synthesis, probably by membrane destabilization.

Flavonoids and related compounds in parasitic disease control

Flavonoids are natural plant compounds increasingly used in therapeutic applications. Their large spectrum of activities depends on their structures and cellular targets. Most recent research shows they are promising drugs for controlling human and animal parasitic diseases. Their multiple effects make it difficult to understand their modes of action, but some of them have been elucidated. This review also deals with their toxicity in mammals.

Hormonal variation in bitches after early or mid-pregnancy termination with aglepristone (RU534)

Seven bitches in early pregnancy (12.8 +/- 3.8 days after ovulation; group 1) and seven bitches in mid-pregnancy (32.0 +/- 1.53 days after ovulation; group 2) were used in this study. For each group, five bitches were treated with 0.10 mg aglepristone (Alizine) kg-1 and this dose was repeated 24 h later. Two control bitches received a placebo. Blood samples were collected at 6 h intervals to determine plasma concentrations of progesterone, dihydro-keto prostaglandin F2 alpha (PGFM), oxytocin, prolactin and cortisol. Parturition occurred in the four control bitches. All bitches treated with aglepristone aborted. In group 1, embryonic death occurred; in group 2, fetal expulsion occurred 60-132 h after administration of aglepristone. After pregnancy termination, the interoestrous interval of aglepristone-treated bitches was significantly shorter than that before treatment. Treatment with aglepristone did not modify plasma concentrations of progesterone, prostaglandin, oxytocin or cortisol within 24 h after its administration, but it induced, in mid-pregnancy (group 2) a discharge of prolactin within 12 h after its administration. As an abortifacient, aglepristone acted on the uterus and, therefore, did not have direct or immediate luteolytic properties. Termination of pregnancy occurred with high plasma progesterone concentrations. Fetal expulsion was characterized by an increase in the concentration of PGFM, but oxytocin and cortisol remained at basal concentrations.

[Antibody avidity: use for the diagnosis of HIV early infection]

Determination of IgG avidity is useful to distinguish primary infection from reactivation or reinfection in viral, parasitic or bacterial infections. For diagnosis of HIV type 1 primary infection, the detection of IgM antibodies is often useless since they are also found in chronic infection. The usual serology (Elisa, western-blot, p24 antigen) may present no interest if done too late (more than 2 or 3 months after infection). Therefore, we have developed a test to determine the avidity of anti-HIV1 antibodies, using 1 M guanidine as denaturing agent. We have adapted the measurement of avidity to the Axsym automatic system for a routine use. Indeed, since requests for avidity determinations are sporadic, the use of microplates is not convenient. Using this assay, we found a low avidity (less than 50%) in immunocompetent and recent infected patients (less than 6 months), compared to old infected patients (more than 12 months) who had high avidity (80 to 100%). However, early treated patients (in the 6 months after contamination) had also low avidities but with a slower development of antibody maturation (8 to 27 months versus 2 to 8 months in non treated patients). To conclude, the determination of the anti-HIV1 avidity, according to the proper procedures explained here (notion of treatment and/or serious immunodepression), may help the physician to date the infection in each new infected patient who might benefit from an early treatment.

[Dynamic study of anti-HIV antibody avidity after cellular immunity restoration under antiretroviral treatment]

We have studied the evolution of the avidity of anti-HIV antibodies, in 14 infected patients with Aids, including 11 patients with severe immunodeficiency at Aids stage and under active antiretroviral therapy (HAART), and 3 non-treated patients with moderate immunodeficiency. These patients have been followed up to 4 years, every 4 months the first year and every 6 months the three others, with HIV1 RNA viral load, CD4 and CD8 cells dosages and anti-HIV avidity measurements (Axsym HIV-1/2), using 1 M guanidine denaturation. A rapid decrease of the viral load was observed under Haart, inducing immune restoration with CD4 and CD8 cells increases (10 and 2-fold respectively). The decrease of anti-HIV avidity (- 20%) has been observed after 5 to 8 months under Haart, with a return to baseline value (84%). The quick restoration of CD4 cells with a persistence of viral antigens at the beginning of treatment has facilitated the selection of novel naive B lymphocytes producing low-affinity antibodies, measured by the decrease of global anti-HIV avidity. The reduction or even clearance of viral antigens under Haart could secondarily induce the selection of B lymphocytes with higher antibody affinity and therefore higher anti-HIV avidity. Thus, this avidity measurement could be used to assess the functional activity of CD4 cells restoration in HIV infected patients under Haart.

[Isolation rooms in the psychiatric environment]

To date, there has been no survey concerning psychiatric isolation rooms in France. We conducted a mail survey in 1993 involving all adult psychiatric care catchment areas covering the French departments. The survey revealed an estimated number of 1560 isolation rooms. Isolation rooms were considered as absolutely necessary in all the departments but also as an unsatisfactory solution by one-third of them. Isolation rooms were usually small and poorly adapted to efficient patient surveillance. Furthermore, equipment was often inadequate, particularly for noise and fire protection. A serious accident (fire, suicide, escape) was reported by large number of departments. The rooms were used for agitated psychotic (84%) and psychopathic (16) people. Although requested by the physician, but also in some cases by the patient, conditions of use and design of isolation rooms may be dangerous both for the patient and the nursing staff. Financial investment devoted to isolation rooms varies greatly and there is no specific control over the number of installation. Construction must comply with precise specifications defined in co-ordination with the experts involved.

[Coronary spasm during repeated anesthesia]

Coronary arterial spasm observed during the course of two repeated anaesthesias in a patient having undergone aorto-femoral bypass grafting is reported by the authors. Such complications are accompanied by serious ventricular arrhythmias, though transient and healing without sequelae. Clinical and electrocardiographic characteristics of peroperative coronary arterial spasm are underlined. In patients prone to developing such spasm, peroperative alkalosis, hypothermia and parasympathetic stimuli should be avoided. Are emphasized the efficiency of preventive treatment with calcium antagonists and that of intravenous nitroglycerin in the treatment of peroperative coronary arterial spasm when it does occur.