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Tau pathologies are detected in the brains of some of the most common neurodegenerative diseases including Alzheimer's disease (AD), Lewy body dementia (LBD), chronic traumatic encephalopathy (CTE), and frontotemporal dementia (FTD). Tau proteins are expressed in six isoforms with either three or four microtubule-binding repeats (3R tau or 4R tau) due to alternative RNA splicing. AD, LBD, and CTE brains contain pathological deposits of both 3R and 4R tau. FTD patients can exhibit either 4R tau pathologies in most cases or 3R tau pathologies less commonly in Pick's disease, which is a subfamily of FTD. Here, we report the isoform-specific roles of tau in FTD. The P301L mutation, linked to familial 4R tau FTD, induces mislocalization of 4R tau to dendritic spines in primary hippocampal cultures that were prepared from neonatal rat pups of both sexes. Contrastingly, the G272V mutation, linked to familial Pick's disease, induces phosphorylation-dependent mislocalization of 3R tau but not 4R tau proteins to dendritic spines. The overexpression of G272V 3R tau but not 4R tau proteins leads to the reduction of dendritic spine density and suppression of mEPSCs in 5-week-old primary rat hippocampal cultures. The decrease in mEPSC amplitude caused by G272V 3R tau is dynamin-dependent whereas that caused by P301L 4R tau is dynamin-independent, indicating that the two tau isoforms activate different signaling pathways responsible for excitatory synaptic dysfunction. Our 3R and 4R tau studies here will shed new light on diverse mechanisms underlying FTD, AD, LBD, and CTE., Competing Interests: The authors declare no competing financial interests., (Copyright © 2024 the authors.)

Olive pulp (Olea europaea) inclusion in the diet of Iberian sows (Sus scrofa) is interesting due to fiber and bioactive compounds content and because both productions are located in the same area. The aim of this trial was to study the effect of olive pulp inclusion at 100 g/kg in Iberian sow’s diet on performance, immunoglobulin and serum parameters, antioxidant status, and fecal microbiota. Forty multiparous Iberian sows (body weight (BW) = 149.6 ± 20.2 kg) were assigned either a control diet (CON) or an experimental diet (PUL) with olive pulp at 100 g/kg. The BW and backfat thickness in sows were measured at post-insemination days 42 and 107, and litter performance was measured on the farrowing day. Blood and fecal samples were collected at gestation day 107. In piglets, blood was sampled when they were 10 days old for immunoglobulin analysis. Albumin, total protein, triglyceride, creatinine, urea, glucose, and Trolox equivalent antioxidant capacity in serum were higher (p < 0.05) in PUL sows than in CON sows. The Enterobacteriaceae, Bifidobacterium spp., and Lactobacillus spp. fecal counts were increased (p < 0.05) with olive pulp supplementation compared with the CON sow group. Olive pulp added to gestating Iberian sow’s diet at 100 g/kg has beneficial effects on the fecal microbiota and antioxidant status, without penalizing other gestation parameters.

This study analyzes the potential use of an Allium -derived compound, propyl propane thiosulfonate (PTSO), as a functional feed additive in aquaculture. Gilthead seabream ( Sparus aurata ) juveniles had their diet supplemented with this Allium -derived compound (150 mg/kg of PTSO) and were compared with control fish. The effects of this organosulfur compound were tested by measuring the body weight and analyzing the gut microbiota after 12 weeks. The relative abundance of potentially pathogenic Vibrio and Pseudomonas in the foregut and hindgut of supplemented fish significantly decreased, while potentially beneficial Lactobacillus increased compared to in the control fish. Shannon's alpha diversity index significantly increased in both gut regions of fish fed with a PTSO-supplemented diet. Regarding beta diversity, significant differences between treatments only appeared in the hindgut when minority ASVs were taken into account. No differences occurred in body weight during the experiment. These results indicate that supplementing the diet with Allium -derived PTSO produced beneficial changes in the intestinal microbiota while maintaining the productive parameters of gilthead seabream juveniles.

The aim of the present study was to ascertain whether an Allium spp. extract rich in organosulfur compounds, such as propyl thiosulfonate (PTSO), added to the feed of growing-finishing pigs at 5 g/kg enhances growth performance or affects the fecal microbiome, the levels of short-chain fatty acids, or the antioxidant capacity of the animals. Fifty male growing pigs (large white) of 23.07 ± 2.87 kg average body weight were randomly allotted to two treatments in a 103-day trial. The trial was divided into two periods, an initial growing phase (56-days) and a finishing phase (47-days). Two dietary treatments for each phase (growing and finishing) were used: a control diet (CON) and an experimental diet consisting of the control diet to which 5 g/kg of Allium spp. extract was added to substitute sepiolite (GAR). Throughout the study, body weight, average daily gain (kg/day, ADG), feed intake (kg/day), and feed conversion ratio (kg/kg) were measured, while the backfat thickness and muscle depth were determined at the end of the study. Besides, feces samples were taken for bacterial counts by means of real-time PCR and short-chain fatty acid (SCFA) profile determination, and the antioxidant capacity was assessed in serum and saliva. In the animals receiving Allium spp. extract (5 g/kg) in the feed, ADG increased ( p < 0.05) throughout the trial, Salmonella spp. and Clostridium spp. counts in feces had decreased ( p < 0.05) when measured on day 56, and, by day 103, Salmonella spp., Clostridium spp., and Enterobacteriaceae counts had decreased ( p < 0.05) and Lactobacillus spp. counts had increased ( p < 0.01) in feces. Regarding the SCFA profile in feces and antioxidant capacity measured in serum and saliva, supplementation with Allium spp. extract significantly increased the levels of propionic, isobutyric, and isovaleric acids and the percentage of total branched fatty acids, while the c2/c3 and (c2 + c4)/c3 ratios were lower ( p < 0.05) in feces; the Trolox equivalent antioxidant capacity and the cupric reducing antioxidant capacity levels in serum were significantly higher in the same pigs on day 103 than on day 0. Consequently, based on the current results, Allium spp. extract rich in organosulfur compounds, added to the diet at 5 g/kg, had a beneficial effect on the microbiota and would seem to be a possible alternative for increasing the growth performance of growing-finishing pigs. However, further studies on the effects of Allium spp. supplementation on carcass quality are necessary.

Thirty entire male Iberian (IB) pigs of 12 kg initial BW were used to study the effects of dietary protein-to-energy ratio on performance, body protein accretion, and tissue composition. Two nutritional regimes were supplied at 3 stages of growth (Phase I, from 12 to 30 kg BW; Phase II, from 30 to 45 kg BW; and Phase III, from 45 to 100 kg BW): the first regime (RefP/E) was formulated to provide optimum protein-to-energy ratios for castrated IB pigs at several stages of growth from 10 to 100 kg BW; the second (IncP/E), for which an overall increase of 2.5 g digestible protein/MJ ME was provided, would allow an increased potential for lean tissue growth presumably well above that expected for the entire male of an obese pig breed. The pigs were surgically castrated at 45 kg BW and slaughtered at about 100 kg BW. In Phases I and II, in which feed was provided ad libitum, no significant differences between dietary treatments in ADG (580 ± 10 and 740 ± 11 g, on average, respectively), G:F (0.475 ± 0.004 and 0.362 ± 0.005, on average, respectively), and gain:ME intake ratio (37.8 ± 0.4 and 26.1 ± 0.4 g/MJ, on average, respectively) were found ( > 0.05). After surgical castration, for the entire fattening period (Phase III), ADFI was fixed and highly restricted. A lower gain:ME intake ratio (14.0 vs. 15.1 g/MJ; < 0.01) was obtained when the diet with the highest digestible protein:ME ratio was offered (IncP/E). With this regime, body protein accretion significantly improved in the IB boar growing from 12 to 45 kg BW, irrespective of the stage of growth, although the amount of protein accreted was notably enhanced at the later stage (75 vs. 85 g/d in Phase I [ < 0.05] and 110.5 vs. 151 g/d in Phase II [ < 0.001]). However, the efficiency of utilization of dietary N remained unchanged irrespective of the diet fed ( > 0.05). In contrast, in the fattening stage, similar daily rates of N retention ( > 0.05) were found, in spite of the observed differences in digestible N intake ( < 0.001). We concluded that the protein (lysine) requirements of the IB boar growing from 12 to 30 kg BW and from 30 to 45 kg BW are met with the supply of 11.5 and 10.2 g digestible protein of ideal AA pattern/MJ ME (0.80 and 0.71 g digestible lysine/MJ ME), respectively. As surgical castration is programmed to be abandoned in European Union by 1 January 2018, this information will be important for the efficient production of the immunologically castrated IB pig, at the earlier stages of growth.

A total of 16 pure-bred Iberian (IB) sows, all of them suckling six piglets, were used, eight of them in each of the two consecutive trials (1 and 2). Daily milk yield and composition were determined weekly over a 34-day lactation period. Within each litter, one piglet at birth and four piglets on day 35 of life were slaughtered. Milk intake per piglet tended to be greater in trial 2 (832 v. 893 g/day; P=0.066), but piglets grew at 168±3.3 g/day, irrespective of the trial. In the IB sow milk, the linoleic (LA) : linolenic (LNA) acid ratio averaged 14.6 and 15.2 in trial 1 and trial 2, respectively. A fivefold increase in piglet body fat content was observed over lactation (P<0.001). Most of this fat (81.4%) was present in the carcass. After 34 days of lactation, whole-body relative content of palmitic, palmitoleic, stearic and oleic acids were very close to those in the milk consumed, suggesting direct deposition. Daily deposition of LA derivatives and of LNA and its derivatives was found to be extremely low (<0.02 g, on average). Moreover, some of the arachidonic acid (ARA) in tissues of the IB piglet at birth disappeared throughout the lactating period. An overall fractional deposition for total fatty acids (FA) was 0.409. Fractional oxidation (disappearance) rates were 0.939 and 0.926 for n-6 and n-3 polyunsaturated FA. The overall rate of disappearance for the major non-essential FA (myristic, palmitic, palmitoleic, stearic and oleic acids), estimated as 1-the overall fractional deposition rate, was 0.546. It is concluded that the high degree of FA unsaturation, high oxidation rate of LA and LNA, and poor synthesis of ARA from LA and of docosahexaenoic acid from LNA found in the suckling piglet might increase the energy cost of whole-body fat accretion, a contributor to the observed low efficiency of use of milk energy for growth.

Piglet body composition at weaning could be a determinant for pig's viability and may be influenced by factors such as the nutritional management followed during suckling. An experiment was conducted to study whether intermittent suckling (IS) affects body composition at weaning and nutrient and energy retention during a 34-day lactation period in Iberian piglets. Litters were subjected to conventional suckling (CS) or IS (n=10 litters of six piglets per treatment) in two trials. All piglets had ad libitum access to creep feed from day 15 onwards. In IS, piglets were progressively separated from the sow for 6, 8 and 10 h daily during the last week of lactation, whereas in CS piglets had continuous access to their dams. Creep feed intake in litters and BW development of individual piglets were measured throughout the 34-day lactation. Within each litter, both at birth and at weaning (day 35), one piglet was used to assess nutrient retention and body composition by the comparative slaughter approach. During days 29 to 35 of the experiment, daily creep feed intake was greater in IS piglets (IS 124, CS 67 g/piglet, P=0.040), and average daily gain differed significantly between groups (IS 190, CS 150 g/day, P=0.010). BW at weaning was higher in the IS than in the CS piglets (IS 8.19, CS 7.48 kg, P=0.011). Empty-body fat and energy content at weaning were higher in the IS compared with CS litters, as well as fat content in the carcass (P=0.04). The IS treatment did not affect empty-body protein deposition, but significantly increased daily retention of fat, energy, ash and calcium, compared with CS litters (P<0.05). Thus, IS in Iberian piglets seems to enhance feed intake, growth rate and retention of some body components, which may contribute to a higher body fat content at weaning and facilitate the weaning process.

The nutrient provision to pregnant females has high impact on the growth and metabolism of their offspring. The objective was to investigate if the expression of hepatic enzymes regulating the fat metabolism was affected in foetuses and adult female mink born by dams fed either a low or an adequate level of protein during late gestation. The relative abundances of acetyl coenzyme A carboxylase (ACC), fatty acid synthase (FAS) and carnitine palmitoyl transferase 1 (CPT1) mRNA were determined by qualitative polymerase chain reaction in the livers of F₀- and F₁-generation dams and in F₁-generation foetuses. Low protein provision during foetal life resulted in a lower expression of FAS in foetal liver but a tendency towards increased expression in the liver of adult dams. There was a tendency towards an effect of life stage of the animal on the expression of ACC resulting in a higher expression among F₁ foetuses exposed to low protein during foetal life than F₀ dams fed a low protein diet during late gestation. The expression of CPT1 was significantly lower among dams exposed to low protein provision during foetal life than controls, possibly indicating a lower rate of mitochondrial β-oxidation. Further investigations are needed to clarify the consequences of these changes for the fat metabolism.

A total of 251 growing-finishing Iberian (IB) pigs, 32 of which were suckling piglets, were used in 5 separate sets of trials. The comparative slaughter procedure was used to determine nutrient and energy retention at several stages of growth from birth to 150 kg BW. A factorial arrangement was used within each set of trials, involving several concentrations of ideal protein in the diets as 1 factor and 2 or 3 levels of feed intake as the other. The main objective of these studies was to derive the optimal protein-to-energy ratio in the diet to allow for the expression of maximum protein deposition rates. The effect of feed restriction on growth performance, protein deposition, and fat deposition was also assessed. According to allometric equations, empty BW (EBW) was related to whole body components or total chemical constituents of empty body mass (P < 0.001). For pigs receiving solid feed, highly statistically significant multiple regression equations were constructed, which derived nutrient (g/kg) or energy (MJ/kg) composition as a function of EBW, dietary protein-to-energy ratio, and level of feeding (P < 0.001). In pigs offered adequate protein-to-energy diets, ADG at each stage of production was predicted as a function of the average BW and feeding level (P < 0.001). It was observed that the estimates of ME required for maintenance and net efficiency of utilization of ME for growth change were within rather narrow ranges throughout the growth stages studied. Preferred values (413 kJ/kg BW(0.75) × d(-1) and 0.593 for ME(m) and k(g), respectively) were obtained by regressing total energy retention (kJ/kg BW(0.75) × d(-1)) against ME intake (kJ/kg BW(0.75) × d(-1)). A multiple-regression approach revealed that in the IB pig, ME costs for protein deposition and fat deposition reach 60 and 62 kJ/g, which is considerably greater than in conventional or lean pig genotypes. In the IB pig, the maximum daily rate of protein deposition (PD(max), g) seemed to follow a linear-plateau shape with a breaking point at 32.5 kg BW, beyond which PD(max) remained at an average rate of 75 g × d(-1). The marginal efficiency of body protein deposition was estimated at each growth stage. In pigs fed on optimal or suboptimal protein-to-energy diets, the relationship between PD and ME intake declined, following a curvilinear pattern with increasing BW; thus, implying relative increases in lipid gain as BW increased.

Sixteen pure-bred Iberian (IB) sows were used in two trials to determine the efficiency of utilization of milk protein and amino acid (AA) for growth in suckling piglets. It was hypothesized that there may be one or more strongly limiting essential AA (EAA) responsible for the slow rate of growth of the IB piglet. This AA will show the highest fractional retention. Daily milk yield and composition were determined weekly over a 34-day lactation period. Within each litter, one piglet at birth and four piglets on d 35 of life were slaughtered. The protein content of the IB sow milk was similar to that reported for conventional breeds. However, branched-chain AA, Thr, Pro, Asp and Ala were in concentrations somewhat below the range of literature values and Arg and Met, substantially above it. Milk intake per piglet tended to be greater in Trial 2 (832 vs. 893 g/day respectively; p = 0.066). However, the IB piglets grew at 168 ± 3.3 g/day, irrespective of the trial. The whole-body protein of piglets at weaning and the protein deposited in their body during the lactating period showed very close AA pattern. Among EAA, His and Arg show the highest fractional retentions (g AA retained/g AA ingested) in whole-body tissues (1.019 ± 0.025 and 0.913 ± 0.017 respectively) and also the highest body to milk ratios (1.50 and 1.41 respectively). Gly and Ala presented, among non essential AA, the highest efficiencies of utilization for tissue deposition (1.803 ± 0.057 and 1.375 ± 0.026 respectively) and body to milk ratios (2.75 and 2.12 respectively). These results suggest that the low efficiency of utilization of milk protein and the low rate of gain of the IB suckling piglet can be explained by a marked shortage in His supply, in addition to the suboptimal milk provision of Arg, Gly and Ala., (© 2010 Blackwell Verlag GmbH.)

Sixteen purebred Iberian (IB) sows were used in two consecutive trials to determine the efficiency of conversion of sow's milk into piglet body weight (BW) gain and the relationship between milk protein and body protein retention and between milk energy yield and body energy retention in the nursing IB piglet. In each trial, four sows were selected in order to evaluate their milk production, litter growth and nutrient balance measurements, together with four additional sows for milk sampling. Litter size was equalized to six piglets. Daily milk yield (MY) was determined weekly by the weigh-suckle-weigh technique over a 34-day lactation period. Piglets were weighed individually at birth and then weekly from day 5 of lactation. Milk samples were collected on days 5, 12, 19, 26 and 34 post partum. The comparative slaughter procedure was used to determine piglet nutrient and energy retention. One piglet from each litter was slaughtered at birth and four on the morning of day 35. Total MY was on average 5.175 ± 0.157 kg/day. The average chemical composition (g/kg) of the milk was 179 ± 4 dry matter, 53.4 ± 1.0 CP, 58.5 ± 3.8 fat, 10.4 ± 0.3 ash and 56.9 ± 2.3 lactose. Milk gross energy (GE) was 4.626 ± 0.145 MJ/kg. Milk intake per piglet tended to increase in trial 2 (832 v. 893 g/day; P = 0.066). Piglet BW gain contained (g/kg) 172.1 ± 1.3 protein, 151.5 ± 3.5 fat, 41.4 ± 0.6 ash and 635 ± 3 water and 10.127 ± 0.126 MJ GE/kg. Throughout the 34-day nursing period, the piglets grew at an average rate of 168 ± 3 g/day. The ratio of daily piglet BW gain to daily MY was 0.195 ± 0.002 g/g and the gain per MJ milk GE intake was 41.9 ± 0.5 g/MJ. The overall efficiency of protein accretion (g CP gain/g CP milk intake) was low and declined in trial 2 (0.619 v. 0.571; P = 0.016). Nutrient and energy deposition between birth and weaning were 27.4 ± 0.5 g/day protein, 24.2 ± 0.8 g/day fat and 1615 ± 40 kJ/day energy. Piglet energy requirements for maintenance were 404 kJ metabolizable energy (ME)/kg BW0.75. ME was used for growth with a net efficiency of 0.584. These results suggest that poor efficiency in the use of sow's milk nutrients rather than a shortage in milk nutrient supply might explain the low growth rate of the suckling IB piglet.

Fifty-eight purebred castrated male Iberian (IB) piglets (initial BW 9.9 ± 0.1 kg) were used in an experiment to determine the effect of dietary protein content (PC) and feeding level (FL) on the rates of BW gain, whole body protein deposition (PD), and energy utilization between 10 and 25 kg of BW using the serial slaughter method. Treatments followed a 4 × 2 factorial arrangement with 4 PC (201, 176, 149, and 123 g of CP/kg of DM) and 2 FL (0.95 and 0.70 × ad libitum) and 6 or 7 piglets per combination of treatments. All diets were formulated to have an optimal AA pattern. Six piglets were slaughtered at the start of the trial to estimate initial body composition. The experimental pigs were individually housed in an environmentally controlled room (27 ± 2°C) until they reached 25 kg of BW, when they were slaughtered and analyzed for body composition. Positive linear effects of dietary PC on ADG, G:F, and gain:ME intake were observed (P < 0.001). Piglets fed at the highest FL showed greater ADG, G:F, and gain:ME intake (P < 0.001). An average increase was estimated to be 38.0 g of gain/MJ of ME intake. Protein deposition increased linearly from 35.6 to 50.9 g/d with increasing dietary PC (P < 0.001). A daily increase was estimated to be 0.35 g of PD/g of CP intake. Although the maximal genetic potential for PD of the IB piglet was not attained, a maximal value of 59.9 g/d for whole-body PD was achieved when the diet provided 201 g of CP/kg of DM and was fed at 0.95 × ad libitum. Piglets on the highest FL deposited on average 39% more body protein (P < 0.001) than restricted piglets. An average value of 4.39 g increase in PD/MJ of ME intake was obtained for diets containing 201 and 176 g of CP/kg of DM. Maintenance energy requirements and net efficiency of utilization of ME for growth, calculated by linear regression of ME intake on body retained energy, were 427 kJ/kg of BW(0.75)·d(-1) and 0.552, respectively. The corresponding partial efficiencies of utilization of ME for protein and fat deposition were 0.378 and 0.672, respectively, considerably less than the accepted values for conventional pig breeds. Practical diets of the young IB piglet should contain at least 201 g of ideal CP/kg of DM.

We evaluated the effect of selective decontamination of the digestive tract (SDD) on the incidence of ventilator-associated pneumonia (VAP) and its associated morbidity and cost in a mixed population of intubated patients. Two hundred seventy-one consecutive patients admitted to the intensive care units (ICUs) of five teaching hospitals and who had an expected need for intubation exceeding 48 h were enrolled and received topical antibiotics or placebo. Uninfected patients additionally received ceftriaxone or placebo for 3 d. VAP occurred in 11.4% of SDD-treated and 29.3% of control-group patients (p < 0.001; 95% confidence interval [CI]: 7.8 to 27.9). The incidence of nonrespiratory infections in the two groups was 19.1% and 30.7%, respectively (p = 0.04; 95% CI: 0.7 to 22.7). Among survivors, the median length of ICU stay was 11 d (interquartile range: 7 to 21.5 d) for the SDD-treated group and 16. 5 d (10 to 30 d) for the control group (p = 0.006). Mean cost per survivor was $11,926 for treated and $16,296 for control-group patients. Mortality was 38.9% and 47.1%, respectively (p = 0.57). In decontaminated patients, the prevalence of gram-negative bacilli fell within 7 d from 47.4% to 13.0% (p < 0.001), whereas colonization with resistant gram-positive strains was higher (p < 0. 05) than in the placebo group. In a mixed population of intubated patients, SDD was associated with a significant reduction of morbidity at a reduced cost. Our findings support the use of SDD in this high-risk group.

Objective: To investigate whether oxygen consumption (VO2) is dependent on oxygen delivery (DO2) in adult respiratory distress syndrome (ARDS) and non-ARDS acute respiratory failure., Design: Intervention study of a consecutive sample of patients admitted to the ICU with the diagnosis of acute respiratory failure., Setting: Tertiary care center., Patients: Thirteen consecutive patients with a diagnosis of ARDS and 11 with a diagnosis of respiratory failure not due to ARDS. Patients were monitored with an oximetric pulmonary artery catheter and mechanically ventilated., Interventions: DO2 was decreased by the application of positive end-expiratory pressure (PEEP) (20 cm H2O), and subsequently increased by an iv infusion of dobutamine (10 micrograms/kg.min)., Results: After the application of PEEP, DO2 decreased significantly in both groups. However, VO2 decreased significantly (p less than .01) only in the ARDS group. When dobutamine was infused, DO2 increased significantly (p less than .01) in both groups, but VO2 increased only in ARDS patients. DO2 correlated significantly with VO2 both in ARDS (r2 = .81, p less than .01) and in non-ARDS (r2 = .38, p less than .05) patients. The correlation coefficient was significantly higher for ARDS than for non-ARDS patients. Comparing the slopes of the regression lines, a stronger dependency of VO2 on DO2 was found in ARDS than in non-ARDS respiratory failure (p less than .001). The oxygen extraction ratio correlated with DO2 in non-ARDS patients (r2 = .49, p less than .05), but not in ARDS patients., Conclusions: VO2 is dependent on DO2 over a wide range of DO2 values in acute respiratory failure. This dependency phenomenon is much stronger in ARDS than in respiratory failure due to other causes. Due to the abnormal dependency of VO2 on DO2, changes in the oxygenation status may not be reflected by changes in mixed venous oxygen saturation in ARDS.

We analyzed the tissue oxygen extraction in 25 patients with acute respiratory failure. Fourteen met the clinical criteria for the adult respiratory distress syndrome (ARDS). The 11 remaining patients had acute respiratory failure with causes different from ARDS. In all cases the changes in the oxygen extraction ratio (O2ER) and in the oxygen consumption (VO2) were evaluated after changing oxygen availability (O2A) with positive end-expiratory pressure (PEEP) and dobutamine infusion. The patients with ARDS showed a change in VO2 parallel to O2A changes, with a significant correlation (r = 0.85); however, no changes were found in O2ER (r = 18). In the patients without ARDS, the changes in O2A did not modify the VO2 (r = 0.02) but there was a significant inverse relationship between DO2 and O2ER (r = -0.70). These findings suggest an abnormal regulation of tissue oxygen extraction and an abnormal dependence of VO2 on O2A in cases with ARDS. Dobutamine therapy, in addition to inotropic effects, could improve a situation of hidden hypoxia, as it is a vasodilator that might act on microvasculature.

Five whole bronchoalveolar lavages were performed in 2 patients with pulmonary alveolar proteinosis with continuous monitoring of mixed venous and arterial oxygen saturation. Hemodynamic parameters and gas-exchange status were measured during the different phases of the lavage. In the phase of filled lung, a significant increase of arterial partial pressure (PaO2) and arterial saturation of oxygen were observed, secondary to a decrease in the intrapulmonary shunt. The mean pulmonary arterial pressure, pulmonary vascular resistances and cardiac index were higher during the filling of the lung as compared to the controls. During the empty lung phase, although PaO2 decreased (without reaching statistical significance), due to an increase in the intrapulmonary shunt, the increase in cardiac output during this phase left the oxygen delivery (DO2) unchanged.

Cytology in blood drawn through a wedged Swan-Ganz catheter appears as a sensitive method for the diagnosis of carcinomatous lymphangitis in patients in whom transbronchial biopsy is considered dangerous or who refuse to undergo the latter procedure. However, its usefulness has not been assessed in critical patients with acute respiratory failure of unknown etiology in whom malignant disease is suspected. We report our experience in two patients admitted to the Intensive Care Unit with acute respiratory failure of unknown etiology: they were a female with breast carcinoma and a male with lymphoma in whom the cytological study of pulmonary capillary blood disclosed malignant cells. The clinical evaluation and the subsequent histological studies confirmed the pulmonary involvement by malignant disease in both cases.

A case is presented of minimum renal trauma, leading to a retroperitoneal hematoma as a consequence of a simple renal cyst rupture as well as an artery contained therein. The etiopathogenicity of this phenomenon is commented. The different clinical manifestations of renal trauma are highlighted, as well as the suspicion of previous renal pathology when a large renal lesion is found secondary to minimum renal trauma. The approach of the renal pediculum must be the first step in the surgical treatment of renal trauma.

Alveolar proteinosis is a relatively rare disease of unclear pathogenesis associated with opportunistic-infections. Although nocardiosis is the most frequent one, only 22 cases have been reported previously and are reviewed here. We present a patient with alveolar proteinosis with nocardiosis treated as an emergency with bilateral bronchopulmonary lavage and antibiotics. No previous cases of this association have been successfully managed in this way.

A rare congenital anomaly of the aortic arch is presented, consisting of an ectasia of the left subclavian artery associated with narrowing of the aortic arch in an asymptomatic twenty-three-year-old woman.