A first glimpse of larval ecology of halibut species in the Gulf of St. Lawrence, Canada.

Knowledge of the larval ecology of winter-spawning fish from the Estuary and Gulf of St. Lawrence, Canada, remains scarce due to the seasonal ice cover that prevents ichthyoplankton sampling using conventional methods. Two winter-spawning species, Atlantic halibut (AH, Hippoglossus hippoglossus) and Greenland halibut (GH, Reinhardtius hippoglossoides), support the most important groundfish fisheries of this area. In March 2020, the authors captured 10 halibut larvae ranging in size from 5 to 14 mm during an opportunistic survey in the GSL onboard an icebreaking vessel. Of these, eight were AH and two GH. Judging by their very small size, the larvae were only a few days old, suggesting that the spawning grounds are close to the capture sites. This effort constitutes a first step in validating the putative spawning areas for these two important GSL stocks. This knowledge is important for the conservation and sustainable management of these fisheries.

Feeding ecology of redfish (Sebastes sp.) inferred from the integrated use of fatty acid profiles as complementary dietary tracers to stomach content analysis.

In the northern Gulf of St. Lawrence (nGSL), redfish (Sebastes mentella and Sebastes fasciatus combined) are at record levels of abundance following the strong recruitment of three consecutive cohorts in 2011-2013 and have become by far the most abundant demersal fish in the region. Understanding redfish trophic relationships is essential for the effective management and conservation of species in the nGSL ecosystem. To date, description and quantification of redfish diet in the region have been restricted to conventional stomach content analysis (SCA). Using analysis of fatty acid (FA) profiles as complementary dietary tracers, the authors conducted multivariate analyses on 350 livers of redfish which were collected in combination with stomach contents during a bottom-trawl scientific survey in August 2017. The predator FA profiles were compared to those of eight different redfish prey types identified as dietary important with SCA. Results suggested similitude between SCA and FA results, with zooplankton prey being more related to small (<20 cm) and medium (20-30 cm) redfish (16:1n7, 20:1n?, 22:1n9 and 20:5n3) than large (≥30 cm) ones, whereas shrimp prey seemed more related to large redfish size classes (18:2n6 and 22:6n3) relative to the small and medium ones. Although the SCA offers a glimpse in the diet only based on the most recently consumed prey, analysis of FA profiles provides a mid-term view indicating pelagic zooplankton consumption on calanoid copepod and confirming high predation pressure on shrimp. This study constitutes the first attempt of combining FA with SCA to assess the diet of redfish, highlights the benefits of FA as a qualitative tool and suggests improvements for future studies.

Reproductive behavior of Atlantic halibut (Hippoglossus hippoglossus) interpreted from electronic tags.

Reproductive timing, location, and behavior are important characteristics that determine marine population dynamics, structure, and resilience to threats, including fishing and climate change. It is challenging to evaluate factors driving variability in these reproductive traits in wild fishes because of the difficulty observing individuals in their natural environments. In the present study, we used high-resolution depth, temperature, and acceleration time series recorded by pop-up satellite archival tags to (1) identify and characterize patterns in depth and acceleration that may be indicative of spawning events in large Atlantic halibut (Hippoglossus hippoglossus), and (2) estimate the effects of individual traits (body size and sex) and environmental factors (location and temperature) on spawning time and frequency. Unique rapid rises observed in the winter depth profiles were interpreted as spawning events. The initiation of the first presumed spawning rise was negatively correlated to water temperature experienced during the prespawning season, suggesting that currently increasing water temperature in the Gulf of St. Lawrence may induce phenological change in halibut spawning time. The number of rises of batch-spawning females was unrelated to female body size. The present study demonstrates how electronic tagging can be used for in-depth characterization of timing, location, and behaviors associated with spawning in a large flatfish species. Such information can inform spatiotemporal management and conservation measures aiming to protect species from directed fishing and by-catch during spawning.

Spatiotemporal variability in diet composition of Greenland halibut (Reinhardtius hippoglossoides) from the eastern Canadian Arctic.

Greenland halibut (Reinhardtius hippoglossoides) sustain one of the most lucrative fisheries in the eastern Canadian Arctic and Labrador Sea. This species also plays an important role in food web connectivity and benthic-pelagic coupling. Despite the relatively rich knowledge of this species, R. hippoglossoides ecology in these specific areas remains poorly understood. The main aim of this study was to characterize the diet of this deepwater fish in the Labrador Sea and Davis and Hudson Straits and characterize the predator-prey relationship with northern shrimp (Pandalus borealis), another commercially important species in the region. Stomach contents analyses were conducted on 1199 fish captured from 2018 to 2020. Small specimens (<20 cm) fed on invertebrates, whereas larger individuals (>60 cm) fed primarily on fish, indicative of size-related changes in diet composition. The relative abundance of Pandalus shrimp species in the environment was reflected in the diet. Location appeared to be the most influential variable on feeding patterns. Distinct oceanographic conditions among areas, resulting in differences in prey availability, could explain these results. Arctic cod (Boreogadus saida) and redfish (Sebastes sp.) were selected in locations where fish prey were the most abundant. These results shed light on the opportunistic nature of R. hippoglossoides and its preference for fish at large size. With the rapidly changing oceanographic conditions of Arctic waters, a distributional change in the biomass of shrimp is expected. Results suggest that an increase in abundance of predatory groundfish species in the system (e.g., Sebastes sp.) could lead to acute predation on shrimp and competition with R. hippoglossoides. By revealing key trophic links within the demersal ecosystem, this work provides valuable information on the development of ecosystem approaches to fisheries management for the region.

Divergent bacterial landscapes: unraveling geographically driven microbiomes in Atlantic cod.

Establishing microbiome signatures is now recognized as a critical step toward identifying genetic and environmental factors shaping animal-associated microbiomes and informing the health status of a given host. In the present work, we prospectively collected 63 blood samples of the Atlantic cod population of the Southern Gulf of Saint Lawrence (GSL) and characterized their 16S rRNA circulating microbiome signature. Our results revealed that the blood microbiome signature was dominated at the phylum level by Proteobacteria, Bacteroidetes, Acidobacteria and Actinobacteria, a typical signature for fish populations inhabiting the GSL and other marine ecosystems. At the genus level, however, we identified two distinct cod groups. While the microbiome signature of the first group was dominated by Pseudoalteromonas, a genus we previously found in the microbiome signature of Greenland and Atlantic halibut populations of the GSL, the second group had a microbiome signature dominated by Nitrobacter and Sediminibacterium (approximately 75% of the circulating microbiome). Cods harboring a Nitrobacter/Sediminibacterium-rich microbiome signature were localized in the most southern part of the GSL, just along the northern coast of Cape Breton Island. Atlantic cod microbiome signatures did not correlate with the weight, length, relative condition, depth, temperature, sex, and salinity, as previously observed in the halibut populations. Our study provides, for the first time, a unique snapshot of the circulating microbiome signature of Atlantic cod populations and the potential existence of dysbiotic signatures associated with the geographical distribution of the population, probably linked with the presence of nitrite in the environment.

Insights into the circulating microbiome of Atlantic and Greenland halibut populations: the role of species-specific and environmental factors.

Establishing long-term microbiome-based monitoring programs is critical for managing and conserving wild fish populations in response to climate change. In most cases, these studies have been conducted on gut and, to a lesser extent, skin (mucus) microbiomes. Here, we exploited the concept of liquid biopsy to study the circulating bacterial microbiome of two Northern halibut species of economic and ecological importance. Amplification and sequencing of the 16S rRNA gene were achieved using a single drop of blood fixed on FTA cards to identify the core blood microbiome of Atlantic and Greenland halibut populations inhabiting the Gulf of St. Lawrence, Canada. We provide evidence that the circulating microbiome DNA (cmDNA) is driven by genetic and environmental factors. More specifically, we found that the circulating microbiome signatures are species-specific and vary according to sex, size, temperature, condition factor, and geographical localization. Overall, our study provides a novel approach for detecting dysbiosis signatures and the risk of disease in wild fish populations for fisheries management, most notably in the context of climate change.

Spatial distribution and speciation of mercury in a recovering deepwater redfish (Sebastes mentella) population from St. Lawrence Estuary and Gulf, Canada.

Mercury (Hg) pollution poses a significant threat to the environment, particularly in the form of methylmercury (MeHg). However, little is known about the distribution and influencing factors of Hg in deep-sea (>200m) fish, which is crucial for assessing potential health risks to fish and humans. In Canada, the deepwater redfish (Sebastes mentella) has been designated as an endangered species. After a 25-year fishing moratorium, the redfish population in the St. Lawrence Estuary and Gulf is recovering, and resuming of commercial fishing and human consumption are expected. This study aimed to investigate the distribution of MeHg and total Hg (THg) in the muscle of redfish, as well as the factors influencing its distribution, and to assess the potential human health risks associated with redfish consumption. The redfish samples (n = 123) were collected by Fisheries and Oceans Canada in 2019. The concentrations of THg and MeHg in redfish muscle were determined to be 93.3 ± 183 ng/g (mean ± SD, wet weight) and 78.2 ± 149 ng/g, respectively. Large redfish (>30 cm) accumulated 20 to 30 times more Hg than small redfish (17-30 cm). Small redfish from the Estuary-Western Gulf had higher levels of MeHg and THg than those from the Laurentian Channel and the Northeast Gulf, but the Hg availability to redfish among the three areas were similar. Significant predictors of MeHg concentrations in redfish muscle were determined to be fish length, muscle moisture, δ15N, and N%. MeHg consumption by the general population with an average fish consumption rate is not anticipated to have adverse effects. This study establishes a baseline for future Hg monitoring in the deep water environments in this region. Further research is required to elucidate the cause-effect relationships between various environmental/biological parameters and Hg accumulation in deep-sea biota.

Ferroptosis and pyroptosis signatures in critical COVID-19 patients.

Critical COVID-19 patients admitted to the intensive care unit (ICU) frequently suffer from severe multiple organ dysfunction with underlying widespread cell death. Ferroptosis and pyroptosis are two detrimental forms of regulated cell death that could constitute new therapeutic targets. We enrolled 120 critical COVID-19 patients in a two-center prospective cohort study to monitor systemic markers of ferroptosis, iron dyshomeostasis, pyroptosis, pneumocyte cell death and cell damage on the first three consecutive days after ICU admission. Plasma of 20 post-operative ICU patients (PO) and 39 healthy controls (HC) without organ failure served as controls. Subsets of COVID-19 patients displayed increases in individual biomarkers compared to controls. Unsupervised clustering was used to discern latent clusters of COVID-19 patients based on biomarker profiles. Pyroptosis-related interleukin-18 accompanied by high pneumocyte cell death was independently associated with higher odds at mechanical ventilation, while the subgroup with high interleuking-1 beta (but limited pneumocyte cell death) displayed reduced odds at mechanical ventilation and lower mortality hazard. Meanwhile, iron dyshomeostasis with a tendency towards higher ferroptosis marker malondialdehyde had no association with outcome, except for the small subset of patients with very high catalytic iron independently associated with reduced survival. Forty percent of patients did not have a clear signature of the cell death mechanisms studied in this cohort. Moreover, repeated moderate levels of soluble receptor of advanced glycation end products and growth differentiation factor 15 during the first three days after ICU admission are independently associated with adverse clinical outcome compared to sustained lower levels. Altogether, the data point towards distinct subgroups in this cohort of critical COVID-19 patients with different systemic signatures of pyroptosis, iron dyshomeostasis, ferroptosis or pneumocyte cell death markers that have different outcomes in ICU. The distinct groups may allow 'personalized' treatment allocation in critical COVID-19 based on systemic biomarker profiles.

Sexual and Emotional Health after Allogeneic Hematopoietic Cell Transplantation: A Comprehensive Review and Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC).

A person's sexual and emotional life is greatly impacted after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This topic is not addressed very much by patients and caregivers. Physical, endocrine and genital chronic graft versus host disease (cGVHD)-related disorders are multiple and intertwined with psychological disorders. The Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) has issued recommendations for a better gynecological monitoring of female recipients after allo-HCT. A patient booklet was also offered to patients in the form of questions and answers to facilitate discussions between patients and caregivers and to improve the management of sexual and emotional life after transplant.

[Sexual and emotional life after allogeneic hematopoietic stem cell transplant: Guidelines and patient booklet from the Francophone Society of Bone marrow Transplant and Cellular therapy (SFGM-TC)]. / Vie sexuelle et affective après allogreffe de cellules souches hématopoïétiques : recommandations et livret patient de la SFGM-TC (Société francophone de greffe de moelle et de thérapie cellulaire).

The Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) organises annual workshops in an attempt to harmonise clinical practices among different francophone transplantation centres. The SFGM-TC harmonisation workshops aim at establishing practical guidelines, on the one hand, from data from the literature and international recommendations and, on the other hand, by consensus in the absence of formally proven data. The sexual and emotional life of allogeneic hematopoietic stem cells transplanted (HSCT) patients is often very impacted and remains a subject relatively little addressed by patients and caregivers. This article is an update from a previous workshop and is accompanied by a patient booklet, which will be included in the post allograft follow-up workbook published by the SFGM-TC. The purpose of these two documents is to facilitate discussions between patients and caregivers on the subject and to present proposals for follow-up and tools to better manage the sexual and emotional life of allotransplanted patients.

Cationic allyl complexes of the rare-earth metals: synthesis, structural characterization, and 1,3-butadiene polymerization catalysis.

Monocationic bis-allyl complexes [Ln(eta(3)-C(3)H(5))(2)(thf)(3)](+)[B(C(6)X(5))(4)](-) (Ln = Y, La, Nd; X = H, F) and dicationic mono-allyl complexes of yttrium and the early lanthanides [Ln(eta(3)-C(3)H(5))(thf)(6)](2+)[BPh(4)](2)(-) (Ln = La, Nd) were prepared by protonolysis of the tris-allyl complexes [Ln(eta(3)-C(3)H(5))(3)(diox)] (Ln = Y, La, Ce, Pr, Nd, Sm; diox = 1,4-dioxane) isolated as a 1,4-dioxane-bridged dimer (Ln = Ce) or THF adducts [Ln(eta(3)-C(3)H(5))(3)(thf)(2)] (Ln = Ce, Pr). Allyl abstraction from the neutral tris-allyl complex by a Lewis acid, ER(3) (Al(CH(2)SiMe(3))(3), BPh(3)) gave the ion pair [Ln(eta(3)-C(3)H(5))(2)(thf)(3)](+)[ER(3)(eta(1)-CH(2)CH=CH(2))](-) (Ln = Y, La; ER(3) = Al(CH(2)SiMe(3))(3), BPh(3)). Benzophenone inserts into the La-C(allyl) bond of [La(eta(3)-C(3)H(5))(2)(thf)(3)](+)[BPh(4)](-) to form the alkoxy complex [La{OCPh(2)(CH(2)CH=CH(2))}(2)(thf)(3)](+)[BPh(4)](-). The monocationic half-sandwich complexes [Ln(eta(5)-C(5)Me(4)SiMe(3))(eta(3)-C(3)H(5))(thf)(2)](+)[B(C(6)X(5))(4)](-) (Ln = Y, La; X = H, F) were synthesized from the neutral precursors [Ln(eta(5)-C(5)Me(4)SiMe(3))(eta(3)-C(3)H(5))(2)(thf)] by protonolysis. For 1,3-butadiene polymerization catalysis, the yttrium-based systems were more active than the corresponding lanthanum or neodymium homologues, giving polybutadiene with approximately 90% 1,4-cis stereoselectivity.

Imaging findings in pyogenic ventriculitis.

INTRODUCTION: Pyogenic ventriculitis is an uncommon but often severe intracranial infection. METHODS: Case report with illustrative CT and MRI imaging. RESULTS: A 49-year-old man presented with an intraparenchymal hematoma with extension of blood into the ventricles. The persistence of intraventricular blood necessitated long term placement of an external ventricular drain. On day 23 after admission, a contrast-enhanced CT scan of the brain showed slight hydrocephalus, irregular debris in the dependent part of the occipital horns and periventricular hypodensities. An MRI scan confirmed the characteristic hallmarks of pyogenic ventriculitis on the T2-weighted, Fluid Attenuated Inversion Recovery (FLAIR), and diffusion-weighted and contrast-enhanced T1-weighted images. CONCLUSION: Neuroimaging is crucial in clearly depicting pyogenic ventriculitis. A contrast-enhanced CT scan, but especially MR imaging, is an ideal tool to reliably diagnose this life-threatening cerebral infection.

Daytime noninvasive ventilatory support for patients with ventilatory pump failure: a narrative review.

Over the past three decades, the use of noninvasive ventilation or "NIV" to assuage symptoms of hypoventilation for patients with early onset or mild ventilatory pump failure has been extended to up to the use of continuous noninvasive ventilatory support (CNVS) at full ventilatory support settings as a definitive alternative to tracheostomy mechanical ventilation. NVS, along with mechanical insufflation-exsufflation, now provides a noninvasive option for the management of both chronic and acute respiratory failure for these patients. The most common diagnoses for which these methods are useful include chest wall deformities, neuromuscular diseases, morbid obesity, high level spinal cord injury and idiopathic, primary or secondary disorders of the ventilatory control. Thus, NVS is being used in diverse settings: critical care units, medical wards, at home, and in extended care. The aim of this review is to examine the techniques used for daytime support.

Cationic methyl complexes of the rare-earth metals: an experimental and computational study on synthesis, structure, and reactivity.

Synthesis, structure, and reactivity of two families of rare-earth metal complexes containing discrete methyl cations [LnMe(2-x)(thf)n]((1+x)+) (x = 0, 1; thf = tetrahydrofuran) have been studied. As a synthetic equivalent for the elusive trimethyl complex [LnMe3], lithium methylates of the approximate composition [Li3LnMe6(thf)n] were prepared by treating rare-earth metal trichlorides [LnCl3(thf)n] with 6 equiv of methyllithium in diethyl ether. Heteronuclear complexes of the formula [Li3Ln2Me9L(n)] (Ln = Sc, Y, Tb; L = Et2O, thf) were isolated by crystallization from diethyl ether. Single crystal X-ray diffraction studies revealed a heterometallic aggregate of composition [Li3Ln2Me9(thf)n(Et2O)m] with a [LiLn2Me9](2-) core (Ln = Sc, Y, Tb). When tris(tetramethylaluminate) [Ln(AlMe4)3] (Ln = Y, Lu) was reacted with less than 1 equiv of [NR3H][BPh4], the dimethyl cations [LnMe2(thf)n][BPh4] were obtained. The coordination number as well as cis/trans isomer preference was studied by crystallographic and computational methods. Dicationic methyl complexes of the rare-earth metals of the formula [LnMe(thf)n][BAr4]2 (Ln = Sc, Y, La-Nd, Sm, Gd-Lu; Ar = Ph, C6H4F-4) were synthesized, by protonolysis of either the ate complex [Li3LnMe6(thf)n] (Ln = Sc, Y, Gd-Lu) or the tris(tetramethylaluminate) [Ln(AlMe4)3] (Ln = La-Nd, Sm, Dy, Gd) with ammonium borates [NR3H][BAr4] in thf. The number of coordinated thf ligands varied from n = 5 (Ln = Sc, Tm) to n = 6 (Ln = La, Y, Sm, Dy, Ho). The configuration of representative examples was determined by X-ray diffraction studies and confirmed by density-functional theory calculations. The highly polarized bonding between the methyl group and the rare-earth metal center results in the reactivity pattern dominated by the carbanionic character and the pronounced Lewis acidity: The dicationic methyl complex [YMe(thf)6](2+) inserted benzophenone as an electrophile to give the alkoxy complex [Y(OCMePh2)(thf)5](2+). Nucleophilic addition of the soft anion X(-) (X(-) = I(-), BH4(-)) led to the monocationic methyl complexes [YMe(X)(thf)5](+).

Early- and late-onset ventilator-associated pneumonia acquired in the intensive care unit: comparison of risk factors.

PURPOSE: To compare risk factors of early- (E) and late-onset (L) ventilator-associated pneumonia (VAP). MATERIALS AND METHODS: An epidemiological survey based on a nosocomial infection surveillance program of 11 intensive care units (ICUs) of university teaching hospitals in Lyon, France, was conducted. A total of 7236 consecutive ventilated patients, older than 18 years and hospitalized in ICUs for at least 48 hours, were studied between 1996 and 2002. Data during ICU stay, patient-dependent risk factors, device exposure, nosocomial infections occurrence, and outcome were collected. The cutoff point definition between E-VAP (six days) was based on the daily hazard rate of VAP. RESULTS: The VAP incidence rate was 13.1%, 356 (37.6%) E-VAP (within 6 days of admission) and 590 (62.4%) L-VAP were reported. Independent risk factor for E-VAP vs L-VAP was surgical diagnostic category (odds ratio [OR], 1.49 [95% confidence interval, 1.07-2.07]), whereas independent risk factors for L-VAP vs E-VAP were older age (OR, 1.01 [1.01-1.02]), high Simplified Acute Physiology Score II (OR, 1.01 [1.00-1.02]), infection on admission (OR=2.22 [1.61-3.03]), another nosocomial infection before VAP (OR, 5.88 [3.33-11.11]), and exposure to central venous catheter before VAP (OR, 4.76 [1.04-20.00]). CONCLUSIONS: E-VAP and L-VAP have different risk factors, highlighting the need for developing specific preventive measures.

Short- and long-term outcomes of heatstroke following the 2003 heat wave in Lyon, France.

BACKGROUND: During August 2003, Europe sustained a severe heat wave that resulted in 14 800 heat-related deaths in France. Most of these excess deaths occurred in urban areas, where maximal temperatures broke all records. Heatstroke is the most severe form of heat-related illness. The clinical course of heatstroke in urban areas of temperate countries is poorly documented. METHODS: During the French heat wave (August 1-20, 2003), we conducted a prospective study in a university hospital located in Lyon, one of the largest metropolitan areas in France. We evaluated survival and functional outcome for 2 years and looked for factors influencing the prognosis. RESULTS: A total of 83 patients presented with heatstroke. The 28-day and 2-year mortality rates were 58% and 71%, respectively. Mortality was influenced as early as admission by the level of fever and the number of organ dysfunctions. Multivariate analysis revealed an independent contribution to mortality if patients came from an institution (hazard ratio [HR], 1.98; 95% confidence interval [CI], 1.05-3.71), used long-term antihypertensive medication (HR, 2.17; 95% CI, 1.17-4.05), or presented at admission with anuria (HR, 5.24; 95% CI, 2.29-12.03), coma (HR, 2.95; 95% CI, 1.26-6.91), or cardiovascular failure (HR, 2.43; 95% CI, 1.14-5.17). Most surviving patients exhibited a dramatic alteration of their functional status at 1 and 2 years. CONCLUSIONS: Heatstroke is associated with poor outcomes in temperate urban areas. This could be explained at least in part by our lack of experience. Western temperate countries need to be more prepared for future heat waves.

EBV-associated hemophagocytic lymphohistiocytosis complicated by severe coagulation disorders and opportunistic infections: case report of a survivor.

The possibility of hemophagocytic lymphohistiocytosis should always be kept in mind when examining/treating a patient with fever of unknown origin and sepsis-like symptoms. Early diagnosis leading to prompt initiation of immunosuppressive therapy as well as aggressive supportive care, including correction of coagulation abnormalities and treatment of opportunistic infections, can decrease mortality.

Non-invasive positive ventilation in the treatment of sleep-related breathing disorders.

This chapter addresses the use of long-term non-invasive positive pressure ventilation (NIPPV) (to the exclusion of continuous positive airway pressure) in the different clinical settings in which it is currently proposed: principally in diseases responsible for hypoventilation characterized by elevated PaCO(2). Nasal masks are predominantly used, followed by nasal pillow and facial masks. Mouthpieces are essentially indicated in case daytime ventilation is needed. Many clinicians currently prefer pressure-preset ventilator in assist mode as the first choice for the majority of the patients with the view of offering better synchronization. Nevertheless, assist-control mode with volume-preset ventilator is also efficient. The settings of the ventilator must insure adequate ventilation assessed by continuous nocturnal records of at least oxygen saturation of haemoglobin-measured by pulse oximetry. The main categories of relevant diseases include different types of neuromuscular disorders, chest-wall deformities and even lung diseases. Depending on the underlying diseases and on individual cases, two schematic situations may be individualized. Either intermittent positive pressure ventilation (IPPV) is continuously mandatory to avoid death in the case of complete or quasi-complete paralysis or is used every day for several hours, typically during sleep, producing enough improvement to allow free time during the daylight in spontaneous breathing while hypoventilation and related symptoms are improved. In case of complete or quasi-complete need of mechanical assistance, a tracheostomy may become an alternative to non-invasive access. In neuromuscular diseases, in kyphosis and in sequela of tuberculosis patients, NIPPV always significantly increases survival. Conversely, no data support a positive effect on survival in chronic obstructive pulmonary disease.

Neurosensory changes in a human model of endothelin-1 induced pain: a behavioral study.

Although pain is a frequent feature in patients with cancer, its etiology is still poorly understood. In recent years, endothelin-1 (ET-1) has become a major target molecule in the etiology of cancer pain. In this randomised, double-blind study the effects of intradermal injection of ET-1 on spontaneous pain, temperature perception and sensation of punctate stimulation were evaluated. Thirty-five subjects were randomised to receive either placebo or one of four concentrations of ET-1 (ranging from 10(-10) to 10(-6)M). Besides assessment of spontaneous pain, three neurosensory testings were performed: (1) cold and warm sensation, (2) cold and heat pain, and (3) punctate stimulation using a von Frey monofilament. ET-1 produced a dose-dependent flare zone that was absent after placebo injection. Subjects reported a short-lasting spontaneous pain upon administration of the highest concentrations of ET-1. Injection of ET-1 induced a long-lasting and dose-dependent punctate hyperalgesia in an area around the injection site (secondary hyperalgesia). Thermal testing revealed a short period of hypoesthesia to non-noxious warm and cold stimuli after some doses of ET-1. In addition to the mechanical hyperalgesia, intradermal injection of ET-1 almost instantaneously induced a state of cold hyperalgesia outlasting the study period (120 min). No development of heat hyperalgesia was observed. The observed psychophysical characteristics of this new model of ET-1 induced nociception indicate its potential as a human experimental model for cancer pain.