Air pollution and health prevention: A document of reflection

Ambient air quality, pollution and its implication on health is a topic of enormous importance that is normally dealt with by major specialists in their particular areas of interest. In general, it is not discussed from multidisciplinary approaches or with a language that can reach everyone. For this reason, the Health Sciences Foundation, from its prevention area, has formulated a series of questions to people with very varied competences in the area of ambient air quality in order to obtain a global panorama of the problem and its elements of measurement and control. The answers have been produced by specialists in each subject and have been subjected to a general discussion that has allowed conclusions to be reached on each point. The subject was divided into three main blocks: external ambient air, internal ambient air, mainly in the work-place, and hospital ambient air and the consequences of its poor control. Along with the definitions of each area and the indicators of good and bad quality, some necessary solutions have been pointed out. We have tried to know the current legislation on this problem and the competences of the different administrations on it. Despite its enormous importance, ambient air quality and health is not usually a topic of frequent presence in the general media and we have asked about the causes of this. Finally, the paper addresses a series of reflections from the perspective of ethics and very particularly in the light of the events that the present pandemic raises. This work aims to provide objective data and opinions that will enable non-specialists in the field to gain a better understanding of this worrying reality.

Comment on: What is the radiation before 5G? A correlation study between measurements in situ and in real time and epidemiological indicators in Vallecas, Madrid, by I. López, N. Félix, M. Rivera, A. Alonso, and C. Maestú

We have read the article recently published by Lopez et al., 2020 (Lopez et al., 2021). This study aimed to find a possible relationship, if any, between exposure to RF-EMF with some health indicators such as sleep, headache, and fatigue collected through surveys, using maximum electromagnetic radiation peak-to-peak measurements. And after a detailed analysis of the study, we want to make some comments on said publication to clarify some aspects.

Intra-Annual Variation of Eddy Diffusion (k zz ) in the MLT, From SABER and SCIAMACHY Atomic Oxygen Climatologies

Atomic oxygen (O) in the mesosphere and lower thermosphere (MLT) results from a balance between production via photo-dissociation in the lower thermosphere and chemical loss by recombination in the upper mesosphere. The transport of O downward from the lower thermosphere into the mesosphere is preferentially driven by the eddy diffusion process that results from dissipating gravity waves and instabilities. The motivation here is to probe the intra-annual variability of the eddy diffusion coefficient (k _zz ) and eddy velocity in the MLT based on the climatology of the region, initially accomplished by Garcia and Solomon (1985, https://doi.org/10.1029/JD090iD02p03850). In the current study, the intra-annual cycle was divided into 26 two-week periods for each of three zones: the northern hemisphere (NH), southern hemisphere (SH), and equatorial (EQ). Both 16 years of SABER (2002-2018) and 10 years of SCIAMACHY (2002-2012) O density measurements, along with NRLMSIS^® 2.0 were used for calculation of atomic oxygen eddy diffusion velocities and fluxes. Our prominent findings include a dominant annual oscillation below 87 km in the NH and SH zones, with a factor of 3-4 variation between winter and summer at 83 km, and a dominant semiannual oscillation at all altitudes in the EQ zone. The measured global average k _zz at 96 km lacks the intra-annual variability of upper atmosphere density data deduced by Qian et al. (2009, https://doi.org/10.1029/2008JA013643). The very large seasonal (and hemispherical) variations in k _zz and O densities are important to separate and isolate in satellite analysis and to incorporate in MLT models.

Characterization of acute kidney injury in critically ill patients with severe coronavirus disease 2019

BACKGROUND

Coronavirus disease 2019 (COVID-19)-associated acute kidney injury (AKI) frequency, severity and characterization in critically ill patients has not been reported.

METHODS

Single-centre cohort performed from 3 March 2020 to 14 April 2020 in four intensive care units in Bordeaux University Hospital, France. All patients with COVID-19 and pulmonary severity criteria were included. AKI was defined using Kidney Disease: Improving Global Outcomes (KDIGO) criteria. A systematic urinary analysis was performed. The incidence, severity, clinical presentation, biological characterization (transient versus persistent AKI; proteinuria, haematuria and glycosuria) and short-term outcomes were evaluated.

RESULTS

Seventy-one patients were included, with basal serum creatinine (SCr) of 69 ± 21 µmol/L. At admission, AKI was present in 8/71 (11%) patients. Median [interquartile range (IQR)] follow-up was 17 (12-23) days. AKI developed in a total of 57/71 (80%) patients, with 35% Stage 1, 35% Stage 2 and 30% Stage 3 AKI; 10/57 (18%) required renal replacement therapy (RRT). Transient AKI was present in only 4/55 (7%) patients and persistent AKI was observed in 51/55 (93%). Patients with persistent AKI developed a median (IQR) urine protein/creatinine of 82 (54-140) (mg/mmol) with an albuminuria/proteinuria ratio of 0.23 ± 20, indicating predominant tubulointerstitial injury. Only two (4%) patients had glycosuria. At Day 7 after onset of AKI, six (11%) patients remained dependent on RRT, nine (16%) had SCr >200 µmol/L and four (7%) had died. Day 7 and Day 14 renal recovery occurred in 28% and 52%, respectively.

CONCLUSION

Severe COVID-19-associated AKI is frequent, persistent, severe and characterized by an almost exclusive tubulointerstitial injury without glycosuria.

Chronic obstructive pulmonary disease (COPD) in Spain and the different aspects of its social impact: a multidisciplinary opinion document

Chronic obstructive pulmonary disease (COPD) is one of the most prevalent diseases in the World, and one of the most important causes of mortality and morbidity. In adults 40 years and older, it affects more than 10% of the population and has enormous personal, family and social burden. Tobacco smoking is its main cause, but not the only one, and there is probably a genetic predisposition that increases the risk in some patients. The paradigm of this disease is changing in Spain, with an increase of women that has occurred in recent years. Many of the physio pathological mechanisms of this condition are well known, but the psychological alterations to which it leads, the impact of COPD on relatives and caregivers, the limitation of daily life observed in these patients, and the economic and societal burden that they represent for the health system, are not so well-known. A major problem is the high under-diagnosis, mainly due to difficulties for obtaining, in a systematic way, spirometries in hospitals and health-care centers. For this reason, the Fundación de Ciencias de la Salud and the Spanish National Network Center for Research in Respiratory Diseases (CIBERES) have brought together experts in COPD, patients and their organizations, clinical psychologists, experts in health economics, nurses and journalists to obtain their opinion about COPD in Spain. They also discussed the scientific bibliometrics on COPD that is being carried out from the CIBERES and speculated on the future of this condition. The format of the meeting consisted in the discussion of a series of questions that were addressed by different speakers and discussed until a consensus conclusion was reached.

The sustainable impact of an educational approach to improve the appropriateness of laboratory test orders in the ICU

INTRODUCTION

Few studies described strategies to improve the use of diagnostic tests in intensive care units (ICU). No study assessed whether their impact was sustained or not. In this study, we assessed whether a multi-faceted intervention for more appropriate use of laboratory testing can decrease the number of tests, is sustainable, is not associated with additional morbidity and represents a potential cost saving.

MATERIAL AND METHODS

An open-label prospective cohort study in two separated units of the same medical intensive care unit (ICU) including respectively 3315 and 2392 consecutive patients. After the observation period (2010), a reduction in ICU A of unnecessary diagnostics tests as part of a program including senior supervisory of juniors' orders, encouragements for orders containment at each everyday round discussions (period 2; 2011). Period 3 (2012) consisted in the prolongation of the protocol as a routine care without supervision; Period 4 (2013) was a new period of observation without intervention. No modification was implemented in ICU B in periods 2-4.

RESULTS

After the intervention, a decrease in the overall number of tests per ICU-patient-days (37.3±5.5 (baseline) to 15.2±3.2 (- 59%); p<0.0001) was observed. The total cost of the tests decreased from 239±41 to 104±28 euros per ICU-patient days; p<0.0001. The effect on laboratory test orders was sustainable in period 3 (-49%) and 4 (-30%). No significant secondary effect of the intervention was observed in period 2. In ICU B, there was no significant change in the overall laboratory test orders in between the periods.

CONCLUSIONS

Laboratory test containment is effective, likely safe and sustainable provided that an educational program is repeatedly promoted, that it makes sense for the whole team, that senior and junior physicians are both committed in the program, and that encouragements for laboratory orders containment at each everyday round discussions.

Autochthonous cutaneous leishmaniasis in urban domestic animals (Felis catus / Canis lupus familiaris) from central-western Venezuela

Leishmaniasis is a zoonotic disease caused by intracellular protozoa of the Leishmania genus that are spread and transmitted by sandflies. Natural infection and clinical disease in domestic cats and dogs appear to be rare or perhaps largely under-reported in endemic areas. However, previous reports on infected domestic animals usually implicate the same Leishmania species that affect humans in tropical and subtropical areas of the world suggesting a potential role for zoonotic transmission. In the present study we assessed a representative sample of cats and dogs from endemic urban / suburban areas of Lara state in central western Venezuela. In both dogs and cats, cutaneous disease exhibits a spectrum of manifestations that range from single papules or nodules, which may evolve into ulcerative, plaque-like or scaly lesions. Cytochrome b (cyt b) PCR gene sequence analysis revealed L. mexicana as the causative agent in all cases, including two human cases proceeding from the same study area at the same time the study was carried out. In order to improve our understanding on feline/canine infection with Leishmania mexicana, and address potential zoonotic concerns it is necessary to characterize its enzootic reservoirs and vectors as well as the possible anthropophilic players linking to the peridomestic and domestic cycles.

Cystinyl and pyroglutamyl-beta-naphthylamide hydrolyzing activities are modified coordinately between hypothalamus, liver and plasma depending on the thyroid status of adult male rats

The hypothalamus determinates metabolic processes in liver through endocrine and autonomic control. Hypothalamic neuropeptides, such as thyrotropin releasing hormone or vasopressin, have been involved in liver metabolism. The thyroid status influences metabolic processes including liver metabolism in modulating those hypothalamic peptides whose functional status is regulated in part by aminopeptidase activities. In order to obtain data for a possible coordinated interaction between hypothalamus, plasma and liver, of some aminopeptidase activities that may partially reflect the hydrolysis of those peptides, pyroglutamyl- (pGluAP) and cystinyl- (CysAP) beta-naphthylamide hydrolyzing activities were determined fluorimetrically, both in their soluble and membrane-bound forms, in eu- hypo- and hyperthyroid adult male rats. Hyperthyroidism and hypothyroidism were induced with daily subcutaneous injections of tetraiodothyronine (300 μg/kg/day) or with 0.03% methimazole in drinking water for 6 weeks. Results demonstrated significant changes depending on the type of enzyme and the thyroid status. The most striking changes were observed for CysAP in liver where it was reduced in hypothyroidism and increased in hyperthyroidism. Significant intra- and inter-tissue correlations were observed. While there were positive inter-tissue correlations between liver, plasma and hypothalamus in eu-and hypothyroid rats, a negative correlation between hypothalamus and liver was observed in hyperthyroidism. These results suggest the influence of thyroid hormones and an interactive role for these activities in the control of liver metabolism. The present data also suggest a role for CysAP and pGluAP activities in liver function linked to their activities in hypothalamus.

Neurally adjusted ventilatory assist as an alternative to pressure support ventilation in adults: a French multicentre randomized trial

PURPOSE

Neurally adjusted ventilatory assist (NAVA) is a ventilatory mode that tailors the level of assistance delivered by the ventilator to the electromyographic activity of the diaphragm. The objective of this study was to compare NAVA and pressure support ventilation (PSV) in the early phase of weaning from mechanical ventilation.

METHODS

A multicentre randomized controlled trial of 128 intubated adults recovering from acute respiratory failure was conducted in 11 intensive care units. Patients were randomly assigned to NAVA or PSV. The primary outcome was the probability of remaining in a partial ventilatory mode (either NAVA or PSV) throughout the first 48 h without any return to assist-control ventilation. Secondary outcomes included asynchrony index, ventilator-free days and mortality.

RESULTS

In the NAVA and PSV groups respectively, the proportion of patients remaining in partial ventilatory mode throughout the first 48 h was 67.2 vs. 63.3 % (P = 0.66), the asynchrony index was 14.7 vs. 26.7 % (P < 0.001), the ventilator-free days at day 7 were 1.0 day [1.0-4.0] vs. 0.0 days [0.0-1.0] (P < 0.01), the ventilator-free days at day 28 were 21 days [4-25] vs. 17 days [0-23] (P = 0.12), the day-28 mortality rate was 15.0 vs. 22.7 % (P = 0.21) and the rate of use of post-extubation noninvasive mechanical ventilation was 43.5 vs. 66.6 % (P < 0.01).

CONCLUSIONS

NAVA is safe and feasible over a prolonged period of time but does not increase the probability of remaining in a partial ventilatory mode. However, NAVA decreases patient-ventilator asynchrony and is associated with less frequent application of post-extubation noninvasive mechanical ventilation.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02018666.

Simplified EEG inverse solution for BCI real-time implementation

EEG brain imaging has become a promising approach in Brain-computer interface applications. However, accurate reconstruction of active regions and computational burden are still open issues. In this paper, we propose to use a simplified forward model that includes the reduction of the cortical dipoles based on Brodmann areas together with state-of-the-art EEG brain imaging techniques. With this approach the well known Beamformers and Greedy Search inverse solutions become feasible for real-time implementation, while guaranteeing lower localization error than previous approaches used in BCI. This methodology was tested with synthetic and real EEG data from a visual attention study. Results show zero localization error in terms of active cortical regions estimation in single 1 s trial datasets, with a computation time of 1.1 s in a non-specialized personal computer. These results open the possibility to obtain in real-time information of active cortical regions in Brain-computer interfaces.

Integral valorisation of waste orange peel using combustion, biomethanisation and co-composting technologies

Although recent research has demonstrated that waste orange peel (WOP) is a potentially valuable resource that can be transformed into high value products, heat generation, biomethanisation and composting might be considered the most feasible alternatives in terms of yield. This study revealed that WOP can be successfully valorised through combustion. However, a previous drying step, which generates hazardous wastewater, is required and harmful NOx are emitted with the flue gases. In contrast, a high yield of renewable methane (280LSTPCH4/kg added COD, chemical oxygen demand) and an organic amendment can be obtained through the thermophilic biomethanisation of WOP following the removal of valuable essential oils from the peel. Co-composting of WOP combined at different proportions (17-83%) with the organic fraction of municipal solid waste (OFMSW) was also demonstrated to be suitable. Moreover, a 37% reduction in odour generation was observed in co-composting of WOP compared to single composting of OFMSW.

Abstract P1-07-19: Spatial analyses of breast cancer in women 15-49 years-old in Rio Grande do Sul, southern Brazil

Breast cancer (BC) rates under 50 years have been increasing over time in several countries. Although the exact impact of BC is not know in low and middle income countries, it's estimated that at least 20% of deaths caused by BC affect women under the ahe of 50 years. In Porto Alegre, the capital of Rio Grande do Sul (RS), Brazil's southernmost state, the incidence of BC in women aged 40-49 years is 165 cases per 100,000, while the mortality rate reaches 25 in 100,000 women. In order to understand BC profile in this age group in the entire state of RS, we established incidence, morbidity and mortality between 2002-2011 through crude and smoothed rates for each municipality. Furthermore, we perform the spatial analysis of these indicators. Incidence data were only available for the state capital, where the rate incidence was 19 and 160 cases per 100,000 women in the age groups of 15-39 and 40-49, respectively. Statewide mortality was 2 and 21 per 100,000 women in the age groups of 15-39 and 40-49, respectively. Hospitalar morbidity associated with BC was 0.6% and 2% in women 15-39 and 40-49 years, respectively. The distribution of morbidity and mortality showed regions with continuously high rates throughout this period with result above 3% and 20 deaths per 100,000 women. In the same areas we did not identified centers specialized in cancer treatment and care. Although there is specific epidemiological surveillance for cancer in Brazil, the coverage is insufficient, especially when it comes to incidence. Morbidity and mortality data showed regions continually affected by high rates, suggesting that specific measures as well as specialized care for women in these regions are necessary. This result is particularly important since current guidelines of the Ministry of Health in Brazil recommend mammographic screening starting at the age of 50 years. The expansion of coverage and access to appropriate treatment is essential for the recognition of risk factors, adoption of effective strategies and reduction of cases and deaths in this group of women. Knowledge of the age distribution of BC cases and BC related deaths is important for the definition of health care policies, which will likely be different in different regions of the world.

Citation Format: Vianna FSL, Vargas F, Gross LG, Nunes LN, Ashton-Prolla P, Camey SA. Spatial analyses of breast cancer in women 15-49 years-old in Rio Grande do Sul, southern Brazil. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-07-19.

Influence of thyroid disorders on the kidney expression and plasma activity of aminopeptidase A

OBJECTIVE

Thyroid disorders may affect blood pressure and renal function modifying factors of the plasmatic and kidney renin-angiotensin system such as aminopeptidase A (AP A) that metabolizes angiotensin II to angiotensin III. We investigated the expression of AP A in the kidney, as well as its enzymatic activity in the plasma of euthyroid, hyperthyroid, and hypothyroid adult male rats.

METHODS

Hyperthyroidism was induced by daily subcutaneous injections of tetraiodothyronine. Hypothyroid rats were obtained by administration of methimazole in drinking water. Expression of AP A was determined by Western blot analysis. Plasma AP A activity was measured fluorometrically using glutamyl-β-naphthylamide as substrate.

RESULTS

While hyperthyroid rats exhibited lower levels of plasma AP A activity than controls, the kidney of hyperthyroid animals expressed significantly higher AP A than controls and hypothyroid animals.

CONCLUSIONS

A discrepancy between the high expression of AP A in kidney of hyperthyroid rats and the low activity of AP A measured in plasma and kidney of hyperthyroid animals was found. The posttranslational influence of environmental biochemical factors may be in part responsible for that divergence.

Physiologic Effects of High-Flow Nasal Cannula Oxygen in Critical Care Subjects

INTRODUCTION

High-flow nasal cannula (HFNC) can deliver heated and humidified gas (up to 100% oxygen) at a maximum flow of 60 L/min via nasal prongs or cannula. The aim of this study was to assess the short-term physiologic effects of HFNC. Inspiratory muscle effort, gas exchange, dyspnea score, and comfort were evaluated.

METHODS

Twelve subjects admitted to the ICU for acute hypoxemic respiratory failure were prospectively included. Four study sessions were performed. The first session consisted of oxygen therapy given through a high-FIO2, non-rebreathing face mask. Recordings were then obtained during periods of HFNC and CPAP at 5 cm H2O in random order, and final measurements were performed during oxygen therapy delivered via a face mask. Each of these 4 periods lasted ∼20 min.

RESULTS

Esophageal pressure signals, breathing pattern, gas exchange, comfort, and dyspnea were measured. Compared with the first session, HFNC reduced inspiratory effort (pressure-time product of 156.0 [119.2-194.4] cm H2O × s/min vs 204.2 [149.6-324.7] cm H2O × s/min, P < .01) and breathing frequency (P < .01). No significant differences were observed between HFNC and CPAP for inspiratory effort and breathing frequency. Compared with the first session, PaO2/FIO2 increased significantly with HFNC (167 [157-184] mm Hg vs 156 [110-171] mm Hg, P < .01). CPAP produced significantly greater PaO2/FIO2 improvement than did HFNC. Dyspnea improved with HFNC and CPAP, but this improvement was not significant. Subject comfort was not different across the 4 sessions.

CONCLUSIONS

Compared with conventional oxygen therapy, HFNC improved inspiratory effort and oxygenation. In subjects with acute hypoxemic respiratory failure, HFNC is an alternative to conventional oxygen therapy. (ClinicalTrials.gov registration NCT01056952.).

Tracheal amylase dosage as a marker for microaspiration: a pilot study

BACKGROUND

Devices that limit microaspiration through the cuffs of endotracheal tubes could help prevent ventilator-associated pneumonia (VAP). The amount of tracheal microaspirations could be a relevant study endpoint. The aim of our study was to assess whether amylase measured in tracheal secretions constituted a relevant marker for microaspiration.

METHODS

Twenty-six patients, intubated for at least 48 h and supplied with a subglottic secretion-suctioning device, constituted a group with a high risk of microaspiration. Twelve non-ventilated patients that required a bronchoscopy procedure constituted a group with a low risk of microaspiration (the control group). Tracheal (T) amylase was compared between the groups. In the intubated group, a series of oral (O), subglottic (Sg) and tracheal (T) suction samples were collected and T/O, T/Sg, Sg/O amylase ratios were determined.

RESULTS

Amylase was measured in 277 (89 Sg, 96 B, 92 T) samples from the intubated group and in 12 T samples from the control group. Tracheal amylase was lower in the control group than the intubated group (191 [10-917] vs. 6661 [2774-19,358] IU/L, P<0.001). Amylase gradually increased from tracheal (6661 [2774-19,358] IU/L), to subglottic (130,750 [55,257-157,717] IU/L), to oral samples (307,606 [200,725-461,300] IU/L), resulting in a median 5.5% T/O ratio. In a subset of intubated patients, T amylase samples were assessed in two different laboratories, and gave reproducible results.

CONCLUSION

Tracheal amylase was easy to collect, transport, and measure. The T/O amylase ratio is a first step towards quantifying oropharyngeal to tracheal microaspiration in mechanically-ventilated patients.

Interaction of emodin, aloe-emodin, and rhein with human serum albumin: a fluorescence spectroscopic study

The interaction of the dihydroxyanthraquinones, emodin (1), aloe-emodin (2), and rhein (3) with human serum albumin (HSA) has been studied through fluorescence spectroscopy. Quenching studies and the association constant of the anthraquinoid compounds 1, 2, and 3 in the presence of HSA were estimated. The binding and quenching studies suggest that only emodin (1) may serve as a useful fluorescence probe for structure/function studies of different emodin binding proteins. No photoinduced binding was observed after irradiation of compounds 1, 2, and 3 in presence of human serum albumin.

Function and expression of renal epithelial sodium transporters in rats with thyroid dysfunction

Thyroid disorders are accompanied by major changes in renal sodium handling and blood pressure. Sodium transporters play a crucial role in regulating sodium excretion. We determined the function and expression of type 3 Na/H (NHE3) exchanger, type 2 Na+K+2Cl co-transporter (NKCC2) co-transporter, NaCl co-transporter (NCC) cotransporter, and epithelial sodium channel (ENaC) in hypoand hyperthyroid rats at 6 weeks after each thyroid disorder induction. We measured the renal response to functional blockade of the tubular sodium transporters, using acetazolamide to inhibit the activity of NHE3, furosemide for NKCC2, hydrochlorotiazide for NCC, and amiloride for ENaC. Expression of sodium transporters was analyzed by measuring the protein abundance by Western blot. The responsiveness to NHE3 inhibition and NHE3 protein was lower in hypothyroid rats and higher in hyperthyroid rats vs controls. Hypothyroid rats showed greater diuretic and natriuretic responses to NKCC2 and ENaC blockade and higher protein abundance of NKCC2 vs controls. Hyperthyroid rats showed greater protein expression of NKCC2 and NCC vs controls. Groups did not differ in responsiveness to NCC blockade. The expression and activity of ENaC were lower in hyperthyroid rats. In conclusion, reduced NHE3 activity may participate in the low blood pressure of hypothyroid rats and elevated NHE3 activity in the high blood pressure of hyperthyroid rats. These proximal alterations are counter-balanced by functional upregulation of NKCC2 and ENaC in downstream nephron segments of hypothyroid rats and by downregulation of αENaC activity and expression in hyperthyroid rats.

Sedation during non-invasive ventilation

Non-invasive ventilation (NIV) is increasingly used in patients with acute respiratory failure, but few data exist regarding current sedation practices during NIV. Mask intolerance or claustrophobia, and delirium and agitation, may lead to NIV failure, requiring endotracheal intubation. Judicious use of sedation during NIV could be one of the valuable options for some of these patients at risk of intubation. Although different sedatives have been used in published studies, the objectives of sedation are similar: allowing mitigation of patient discomfort and obtaining the desired level of sedation. Whatever the sedative used, the goal is to achieve sedation to a point where the patients are awake and arousable and comfortable. Pilot studies suggest that continuous infusion of a single sedative agent may decrease patient discomfort, with no significant effects on respiratory drive, respiratory pattern, or hemodynamics. In addition, gas exchange improved under NIV with sedation. While the current limited data available suggests that sedation during NIV is safe and feasible, more widespread application should await the results of randomized clinical trials.

Diaphragm ultrasonography to estimate the work of breathing during non-invasive ventilation

PURPOSE

Ultrasonography allows the direct observation of the diaphragm. Its thickness variation measured in the zone of apposition has been previously used to diagnose diaphragm paralysis. We assessed the feasibility and accuracy of this method to assess diaphragmatic function and its contribution to respiratory workload in critically ill patients under non-invasive ventilation.

METHODS

This was a preliminary physiological study in the intensive care unit of a university hospital. Twelve patients requiring planned non-invasive ventilation after extubation were studied while spontaneously breathing and during non-invasive ventilation at three levels of pressure support (5, 10 and 15 cmH(2)O). Diaphragm thickness was measured in the zone of apposition during tidal ventilation and the thickening fraction (TF) was calculated as (thickness at inspiration - thickness at expiration)/thickness at expiration. Diaphragmatic pressure-time product per breath (PTP(di)) was measured from oesophageal and gastric pressure recordings.

RESULTS

PTP(di) and TF both decreased as the level of pressure support increased. A significant correlation was found between PTP(di) and TF (ρ = 0.74, p < 0.001). The overall reproducibility of TF assessment was good but the coefficient of repeatability reached 18% for inter-observer reproducibility.

CONCLUSIONS

Ultrasonographic assessment of the diaphragm TF is a non-invasive method that may prove useful in evaluating diaphragmatic function and its contribution to respiratory workload in intensive care unit patients.

Echocardiographic evaluation and N-terminal pro-brain natriuretic peptide measurement of patients hospitalized for heart failure during weaning from mechanical ventilation

BACKGROUND

Weaning patients with heart failure who have required mechanical ventilation remains challenging. We evaluated echocardiographic indexes and N-terminal pro-brain natriuretic peptide (NT-proBNP) as markers of acute cardiac dysfunction before and after spontaneous breathing trials (SBT) in such patients to assess their ability to predict subsequent successful extubation.

METHODS

Forty-four patients who underwent their first SBT were prospectively included. Plasma levels of NT-proBNP and transthoracic echocardiography indices including cardiac index, E/A ratio and E/Ea ratio were recorded immediately before commencing and just before the end of SBT.

RESULTS

Ten patients (22.7%) failed their SBT. No significant difference was observed concerning baseline echocardiographic data and NT-proBNP level between the patients who succeeded the SBT or those that failed. Cardiac index increased significantly at end-SBT in patients who passed (3.3 [3.06-3.77] vs. 3 [2.68-3.3] L/min/m(2), P<0.001), whereas it remained unchanged in those that failed. E/Ea ratio (16.8 [8.5-27.3] vs. 10.7 [6.7-20.5], P=0.006) and NT-proBNP level (8199 [3106-10949] vs. 4200 [1855-7125] pg/mL, P=0.004) increased significantly in those who failed the SBT, in contrast to the weaning success group where they remained unchanged.

CONCLUSION

Neither NT-proBNP level nor the studied echocardiographic indices before SBT were able to predict SBT outcome in patients presenting with severe heart failure. Failure to increase the cardiac index and increases in both E/Ea ratio and NT-proBNP levels were seen at end-SBT in patients who failed the SBT, and may reflect failure of myocardial reserve to cope with the stress of SBT.

[Changes in nutritional state, metabolic control and treatment of type 1 diabetes in the last 20 years]

OBJECTIVE

The aim of this study is to describe changes in anthropometric characteristics, metabolic control, treatment and prevalence of overweight in diabetic children (DM1) from 2007 compared with another similar group from 1986.

PATIENTS AND METHODS

Observational retrospective study of two groups of diabetic children (n=90). The collection of variables has been made at two cross-sections, 1986 and 2007. The studied variables were: age, years of DM1, sex, weight, height, BMI (and their Z values), HbA(1c) and treatment with insulin (type, number of doses, IU/day and IU/kg/day).

RESULTS

In 2007 group there is a significant increase in Z-weight and Z-BMI (P=.001) when compared with the 1986 group. There was a negative relationship between the years with DM1 and Z-height (P=.05) in the 1986 group. The value of HbA(1c) was lower in the 2007 group (P=.001), but the dose of insulin (IU/day and IU/kg/day) was similar in both groups. The number of daily doses of insulin was higher in the 2007 group (P<.001), the use of insulin analogues dominated overall. A statistically significant relationship between HbA(1c) and treatment with insulin (dose injections, insulin type) was not found. The prevalence of overweight (14.6% vs 2.4%) was significantly higher in the 2007 Group (P=.001).

CONCLUSIONS

The metabolic control (HbA(1c)) had improved and the use of multiple daily doses of insulin has been become the standard, but the prevalence of overweight has increased. We must monitor the emergence of insulin resistance and cardiovascular risk factors in this sensitive population to prevent early cardiovascular disease.

Role of sympathetic tone in BSO-induced hypertension in mice

BACKGROUND

We investigated the contribution of the sympathetic tone to the hypertension induced by chronic administration of buthionine sulfoximine (BSO) and characterized this model in mice.

METHODS

Three experiments were performed. In experiment I, four groups of CBA-C57 male mice were used: controls and three groups that received oral BSO at 5, 10, or 20 mmol/l. In experiment II, the alpha(1)-adrenergic blocker prazosin was orally administered (10 mg/100 ml) to control and BSO-treated mice. All treatments were maintained for 5 weeks. Body weight (BW), tail blood pressure (BP), and heart rate (HR) were measured weekly. Direct mean arterial pressure (MAP) and morphological, metabolic, plasma, and renal variables were measured at the end of the experiments. In experiment III, the acute response of MAP and HR to the ganglionic blocker pentolinium (10 mg/kg intravenous) was used to further evaluate the sympathetic contribution to BP and HR in control and BSO-treated mice.

RESULTS

BSO produced dose-related increases in BP (control, 115 +/- 0.5; BSO-5, 141 +/- 0.5; BSO-10, 151 +/- 0.9; BSO-20, 163 +/- 1.1 mm Hg) and HR and augmented plasma noradrenaline, brainstem isoprostane levels, and total urinary isoprostane excretion. BSO did not produce cardiac hypertrophy and did not modify metabolic or plasma variables, or creatinine clearance, proteinuria, or renal morphology. Chronic prazosin markedly reduced MAP (control, 101 +/- 4.7; prazosin, 95 +/- 1.29; BSO-10, 130 +/- 2.9; BSO-10 +/- prazosin, 98 +/- 0.9) and HR. Acute pentolinium produced a greater percentage MAP (control, 43 +/- 4.2; BSO-10, 66 +/- 4.5) and HR decrease in BSO-treated mice vs. controls.

CONCLUSION

Sympathetic tone plays a major role in the increased BP and HR of BSO hypertensive mice.

Mechanisms of hydrogen peroxide-induced vasoconstriction in the isolated perfused rat kidney

The vasoconstrictor effect of hydrogen peroxide (H(2)O(2)) on isolated perfused rat kidney was investigated. H(2)O(2) induced vasoconstriction in the isolated rat kidney in a concentration-dependent manner. The vasoconstrictor effects of H(2)O(2) were completely inhibited by 1200 U/ml catalase. Endothelium-removal potentiated the renal response to H(2)O(2). The H(2)O(2) dose-response curve was not significantly modified by administration of the NO inhibitor L-NAME (10(-4) mol/l), whereas it was increased by the non-specific inhibitor of K+-channels, tetraethylammonium (3.10(-3) mol/l). Separately, removal of extracellular Ca(2+), administration of a mixture of calcium desensitizing agents (nitroprusside, papaverine, and diazoxide), and administration of a protein kinase C (PKC) inhibitor (chelerythrine, 10(-5) mol/l) each significantly attenuated the vasoconstrictor response to H(2)O(2), which was virtually suppressed when they were performed together. The pressor response to H(2)O(2) was not affected by: dimethyl sulfoxide (7.10(-5) mol/l) plus mannitol (3.10(-5) mol/l); intracellular Ca(2+) chelation using BAPTA (10(-5) mol/l); calcium store depletion after repeated doses of phenylephrine (10(-5) g/g kidney); or the presence of indomethacin (10(-5) mol/l), ODYA (2.10(-6) mol/l) or genistein (10(-5) mol/l). We conclude that the vasoconstrictor response to H(2)O(2) in the rat renal vasculature comprises the following components: 1) extracellular calcium influx, 2) activation of PKC, and 3) stimulation of pathways leading to sensitization of contractile elements to calcium. Moreover, a reduced pressor responsiveness to H(2)O(2) in female kidneys was observed.

Studies of the photooxidant properties of antibacterial fluoroquinolones and their naphthalene derivatives

We synthesized and determined the production of reactive oxygen species (ROS) as 1O2, *-O2, *OH, H2O2 during the photolysis with UV-A light of three antibacterial quinolones and their naphthyl ester derivatives. Singlet oxygen and ROS dose-dependant generation from norfloxacin (1), enoxacin (2), ciprofloxacin (3) and their respective naphthyl ester derivatives 4-6 were detecting in cell-free systems by the histidine assay and by luminol-enhanced chemiluminescence (LCL). Both the electronic absorption and emission spectra were quantified and their photostability determined. The antibacterial activity in darkness and under irradiation of compounds 4, 5 and 6 was tested on E. coli and compared with their parent drugs.

Influence of surgical treatment timing on mortality from necrotizing soft tissue infections requiring intensive care management

PURPOSE

Surgical treatment is crucial in the management of necrotizing soft tissue infections (NSTIs). The aim of this study was to determine the influence of surgical procedure timing on hospital mortality in severe NSTI.

METHODS

A retrospective study including 106 patients was conducted in a medical intensive care unit equipped with a hyperbaric chamber. Data regarding pre-existing conditions, intensive care and surgical management were included in a logistic regression model to determine independent factors associated with hospital mortality.

RESULTS

Overall hospital mortality was 40.6%. In multivariate analysis, underlying cardiovascular disease, SAPS II, abdominoperineal compared to limb localization, time from the first signs to diagnosis <72 h, and time from diagnosis to surgical treatment >14 h in patients with septic shock were independently associated with hospital mortality.

CONCLUSION

In patients with NSTI and septic shock, hospital mortality is influenced by the timing of surgical treatment.

Tickborne encephalitis, southwestern France

We report an autochthonous human case of tickborne encephalitis (TBE) in the Bordeaux area, southwestern France. The patient was a farmer who had severe encephalomyelitis. ELISA and neutralization assay of serum and cerebrospinal fluid established the diagnosis. This potential new endemic focus for TBE virus should be further investigated.

The majority of cases of neonatal diabetes in Spain can be explained by known genetic abnormalities

BACKGROUND

Neonatal diabetes is a rare disease characterized by hyperglycaemia within the first 3 months of life and requiring insulin treatment; it can either be transient (TNDM) or permanent (PNDM). Alterations at band 6q24 and heterozygous activating mutations in KCNJ11, the gene encoding the pore-forming subunit of the KATP channel, can cause neonatal diabetes. Aims We screened the 6q24 region, KCNJ11, GCK, FOXP3 and IPF1 genes for mutations in families with PNDM or TNDM to establish a phenotype-genotype correlation.

METHODS

Twenty-two patients with neonatal diabetes were recruited. Inclusion criteria were insulin-treated diabetes diagnosed within the first 3 months and insulin treatment for at least 15 days. Clinical data were recorded in a questionnaire.

RESULTS

We identified 17 genetic alterations in our patients: six alterations at the 6q24 band associated with TNDM and nine mutations in KCNJ11, five of which were novel. The analysis for a phenotype-genotype correlation showed that patients with 6q24 alterations had a lower birth weight and were diagnosed earlier than patients with KCNJ11 mutations. At follow-up of the TNDM patients with genetic alterations, 43% developed diabetes or impaired glucose tolerance in later life (one with 6q24 duplication and two with N48D and E227K mutations at KCNJ11 gene). Furthermore, half the first-degree relatives who carried a genetic alteration but who had not suffered from neonatal diabetes were diagnosed with diabetes or impaired glucose tolerance before the age of 30 years.

CONCLUSIONS

KCNJ11 mutations are common in both TNDM and PNDM and are associated with a higher birth weight compared with patients with 6q24 abnormalities. Patients with TNDM should be screened for abnormalities in glucose metabolism in adult life.

Tickborne encephalitis, southwestern France

We report an autochthonous human case of tickborne encephalitis (TBE) in the Bordeaux area, southwestern France. The patient was a farmer who had severe encephalomyelitis. ELISA and neutralization assay of serum and cerebrospinal fluid established the diagnosis. This potential new endemic focus for TBE virus should be further investigated.