A novel, green, low-cost chitosan-starch hydrogel as potential delivery system for plant growth-promoting bacteria.

The study examines the use of macrobeads for the controlled-release of bacteria. Macrobeads were prepared by an easy dripping-technique using 20/80 wt/wt chitosan-starch blends and sodium tripolyphosphate as cross-linking agent. The resulting polymeric matrix was examined by SEM, XRD, TGA, and solid-RMN. The swelling-equilibrium, thermal behaviour, crystallinity, and size of macrobeads were affected by the autoclave-sterilization. The diameter of the sterilized xerogel was c.a. 1.6 mm. The results suggested that ionotropic-gelation and neutralization were the mechanisms underlying hydrogel formation. Plant growth-promoting bacteria (PGPB) were loaded into macrobeads separately or co-inoculated. Bacteria loaded macrobeads were dried and stored. Bacteria survived at least 12 months in orders of 109 CFU of A. brasilense/g and 108 CFU of P. fluorescens/g. Bacterial release in sterile saline solution tended to a super Case-II transport mechanism. Polymeric-matrix release efficiently both PGPB in natural soils, which uncovers their potential for the formulation of novel and improved biofertilizers.

Characterization of a lectin from the craysfish Cherax quadricarinatus hemolymph and its effect on hemocytes.

Lectins participate in the immune mechanisms of crustaceans. They have been considered as humoral receptors for pathogen-associated molecular patterns; however, some reports suggest that lectins could regulate crustacean cellular functions. In the present study, we purified and characterized a serum lectin (CqL) from the hemolymph of Cherax quadricarinatus by affinity chromatography and determined its participation in the regulation of hemocytes' oxidative burst. CqL is a 290-kDa lectin in native form, constituted by 108, 80, and 29-kDa subunits. It is mainly composed of glycine, alanine, and a minor proportion of methionine and histidine. It showed no carbohydrates in its structure. CqL is composed of several isoforms, as determined by 2D-electrophoresis, and shows no homology with any crustacean protein as determined by Lc/Ms mass spectrometry. CqL agglutinated mainly rat and rabbit erythrocytes and showed a broad specificity for monosaccharides such as galactose, glucose, and sialic acid, as well as for glycoproteins, such as porcine stomach and bovine submaxillary mucin and fetuin. It is a Mn(2+)-dependent lectin. CqL recognized 8% of crayfish granular hemocytes and increased 4.2-fold the production of hemocytes' superoxide anion in vitro assays when compared with non-treated hemocytes. This effect showed the same specificity for carbohydrates as hemagglutination; moreover, superoxide dismutase and diphenyleneiodonium chloride were effective inhibitors of CqL oxidative-activation. The CqL homoreceptor is a 120-kDa glycoprotein identified in the hemocytes lysate. Our results suggest that CqL participates actively in the regulation of the generation of superoxide anions in hemocytes using NADPH-dependent mechanisms.

Inhibition of cAMP-dependent protein kinase A: a novel cyclo-oxygenase-independent effect of non-steroidal anti-inflammatory drugs in adipocytes.

1. Non-steroidal anti-inflammatory drugs (NSAIDs) [acetylsalicylic acid (ASS), naproxen, nimesulide and piroxicam] decreased adrenaline- or dibutyryl cAMP-stimulated glycerol release in isolated adipocytes. We aimed to determine the mechanism of this NSAIDs action. 2. Non-steroidal anti-inflammatory drugs decreased cAMP-dependent protein kinase A (PKA) activity in rat adipocyte lysates and in a commercial bovine heart PKA holoenzyme. If added before cAMP, NSAIDs impaired PKA activation by the cyclic nucleotide; however, if PKA was first activated by cAMP, NSAIDs were ineffective. NSAIDs were also ineffective against PKA catalytic subunits. 3. Consequently, NSAIDs lowered hormone-sensitive lipase translocation from cytosol to lipid storage droplets in adipocytes lysates, the critical event to promote lipolysis. 4. These results indicate that inhibition of PKA activation explains NSAIDs-induced decrease in adrenaline-stimulated lipolysis. We suggest that reproduction of such inhibition in nociceptive cells might enhance the understanding of the mechanism underlying the analgesic effects of NSAIDs.

Root phospholipids in Azospirillum-inoculated wheat seedlings exposed to water stress.

Azospirillum-plant association is accompanied by biochemical changes in roots which, in turn, promote plant-growth and tolerance to water stress. To shed light on the possible factors underlying these effects, roots from Azospirillum brasilense Sp245-inoculated Triticum aestivum seedlings growing in darkness under osmotic stress were analyzed for phospholipid (PL) composition, fatty acid (FA) distribution profiles and degree of unsaturation of the major PL classes. Azospirillum inoculation diminished ion leakage and increased 2,3,5-tripheniltetrazolium reducing ability in roots of well irrigated and water-stressed wheat seedlings. Total root PL content remained unaltered in all treatments. Six PL classes were detected, phosphatidylcholine (PC) and phosphatidylethanolamine (PE) comprising over 80% of the total. While water stress increased PC content and diminished that of PE, none of these changes were observed either under Azospirillum inoculation alone or when both treatments were combined. The major FAs found in both PC and PE were 16:0, 18:0, 18:1, 18:2, and 18:3. Higher PC and lower PE unsaturation than in well irrigated controls were observed in roots from Azospirillum-inoculated, water-stressed seedlings. Azospirillum inoculation could contribute to protect wheat seedlings from water stress through changes in the FA distribution profiles of PC and PE major root phospholipids.

[Domiciliary noninvasive positive pressure ventilation in chronic alveolar hypoventilation]. / Ventilación domiciliaria no invasiva a presión positiva en hipoventilación alveolar crónica.

Effectiveness of treatment with domiciliary nocturnal noninvasive positive pressure ventilation is analyzed in a group of patients with chronic alveolar hypoventilation of different etiologies. It was applied with two levels of pressure (BiPAP) via nasal mask. Criteria for evaluation were symptomatology and improvement in gas exchange. Data were analyzed by Student t tests. A total of 13 patients were included, mean age 55.7 range 20 to 76 years (5 male 8 female). Main diagnosis was tuberculosis in 6, four of them having had surgical procedure (thoracoplasty 2, frenicectomy 1 and neumonectomy 1), myopathy 3 (myasthenia gravis 1, muscular dystrophy 1 and diaphragmatic paralysis 1), obesity-hypoventilation syndrome 1, escoliosis 1, bronchiectasis 1 and cystic fibrosis 1. These last two patients were on waiting list for lung transplantation. At the moment of consultation, the symptoms were: dysnea 13/13 (100%), astenia 13/13 (100%), hypersomnolency 10/13 (77%), cephalea 9/13 (69%), leg edema 6/13 (46%), loss of memory 6/13 (46%). Regarding gas exchange, they showed hypoxemia and hypercapnia. Mean follow up was of 2.2 years (range 6 months to 4 years). Within the year, all 13 patients became less dyspneic. Astenia, hypersomnolency, cephalea, leg edema and memory loss disappeared. Improvement in gas exchange was: PaO2/FiO2 from 269 +/- 65.4 (basal) to 336.7 +/- 75.3 post-treatment (p = 0.0018). PaCO2 from 70.77 +/- 25.48 mmHg (basal) to 46.77 +/- 8.14 mmHg (p = 0.0013). Ventilatory support was discontinued en 5 patients: three because of pneumonia requiring intubation and conventional mechanical ventilation, two of them died and one is still with tracheostomy; One patient with bronchiectasis and one with cystic fibrosis were transplanted. The remaining eight patients are stable. In conclusion, chronic alveolar hypoventilation can be effectively treated with domiciliary nocturnal noninvasive ventilation. Long term improvement in symptomatology and arterial blood gases can be obtained without significant complications.

[Acute eosinophilic pneumonia. Case report and review of the literature]. / Neumonía eosinofílica aguda. Presentación de un caso y revisión de la literatura.

A 37 year old female smoker was admitted with an acute episode of fever and pulmonary infiltrates followed by respiratory failure requiring mechanical ventilation in less than 24 hours. After empiric antibiotic therapy fiberoptic bronchoscopy and bronchoalveolar lavage (BAL) were carried out. Abnormal findings were limited to highly increased eosinophilic count in BAL. Blood eosinophils were normal. Acute eosinophilic pneumonia was diagnosed and methyl prednisolone was administered; 48 hours afterwards, infiltrates had partially resolved and the patient was weaned from ventilator. After two years follow up, she has not had recurrences of the episode, is asymptomatic and her chest Xray is normal. A review of the literature is presented and physiopathological mechanisms for acute eosinophilic pneumonia are considered. Acute eosinophilic pneumonia is a rare but potentially curable cause of respiratory failure that should be included in diagnostic considerations.

Ventilación domiciliaria no invasiva a presión positiva en hipoventilación alveolar crónica. / [Domiciliary noninvasive positive pressure ventilation in chronic alveolar hypoventilation]

Effectiveness of treatment with domiciliary nocturnal noninvasive positive pressure ventilation is analyzed in a group of patients with chronic alveolar hypoventilation of different etiologies. It was applied with two levels of pressure (BiPAP) via nasal mask. Criteria for evaluation were symptomatology and improvement in gas exchange. Data were analyzed by Student t tests. A total of 13 patients were included, mean age 55.7 range 20 to 76 years (5 male 8 female). Main diagnosis was tuberculosis in 6, four of them having had surgical procedure (thoracoplasty 2, frenicectomy 1 and neumonectomy 1), myopathy 3 (myasthenia gravis 1, muscular dystrophy 1 and diaphragmatic paralysis 1), obesity-hypoventilation syndrome 1, escoliosis 1, bronchiectasis 1 and cystic fibrosis 1. These last two patients were on waiting list for lung transplantation. At the moment of consultation, the symptoms were: dysnea 13/13 (100

), astenia 13/13 (100

), hypersomnolency 10/13 (77

), cephalea 9/13 (69

), leg edema 6/13 (46

), loss of memory 6/13 (46

). Regarding gas exchange, they showed hypoxemia and hypercapnia. Mean follow up was of 2.2 years (range 6 months to 4 years). Within the year, all 13 patients became less dyspneic. Astenia, hypersomnolency, cephalea, leg edema and memory loss disappeared. Improvement in gas exchange was: PaO2/FiO2 from 269 +/- 65.4 (basal) to 336.7 +/- 75.3 post-treatment (p = 0.0018). PaCO2 from 70.77 +/- 25.48 mmHg (basal) to 46.77 +/- 8.14 mmHg (p = 0.0013). Ventilatory support was discontinued en 5 patients: three because of pneumonia requiring intubation and conventional mechanical ventilation, two of them died and one is still with tracheostomy; One patient with bronchiectasis and one with cystic fibrosis were transplanted. The remaining eight patients are stable. In conclusion, chronic alveolar hypoventilation can be effectively treated with domiciliary nocturnal noninvasive ventilation. Long term improvement in symptomatology and arterial blood gases can be obtained without significant complications.

Neumonía eosinofílica aguda. Presentación de un caso y revisión de la literatura. / [Acute eosinophilic pneumonia. Case report and review of the literature]

A 37 year old female smoker was admitted with an acute episode of fever and pulmonary infiltrates followed by respiratory failure requiring mechanical ventilation in less than 24 hours. After empiric antibiotic therapy fiberoptic bronchoscopy and bronchoalveolar lavage (BAL) were carried out. Abnormal findings were limited to highly increased eosinophilic count in BAL. Blood eosinophils were normal. Acute eosinophilic pneumonia was diagnosed and methyl prednisolone was administered; 48 hours afterwards, infiltrates had partially resolved and the patient was weaned from ventilator. After two years follow up, she has not had recurrences of the episode, is asymptomatic and her chest Xray is normal. A review of the literature is presented and physiopathological mechanisms for acute eosinophilic pneumonia are considered. Acute eosinophilic pneumonia is a rare but potentially curable cause of respiratory failure that should be included in diagnostic considerations.

El aumento del calcio ionizado intracelular depende de algún factor presente en el suero de las pacientes preeclámpticas / The intracellular increase of ionized calcium depend on some factor present in pre-eclamptic patient sera

En trabajos previos nuestro grupo ha demostrado que la concentración intracelular de calcio ionizado es mayor en pacientes con preeclampsia que en embarazadas normotensas y que estas cifras correlacionan con la tensión arterial. Ambos indicadores se normalizan 6 semanas después del parto. Con el fin de investigar la posibile participación de factores solubles en el plasma, en el aumento del calcio libre intracelular, se estudiaron 8 pacientes preeclámpticas diagnosticadad por los criterios del Colegio Americano de Ginecólogos y Obstetras. Como grupo testigo se incluyeron 8 embarazadas normotensas pareadas por edad cronológica y gestacional. Para medir flujos de calcio transmembrana se utilizaron plaquetas de varones sanos. Las plaquetas fueron incubadas durante 0, 15, 30 y 60 minutos en suero de pacientes preeclámpticas o de embarazadas normotensas marcado con Ca. Las diferencias en el transporte de calcio se evaluaron con análisis de varianza de Kruskal Wallis. El transporte de calcio fue mayor cuando las plaquetas se incubaron en suero de pacientes preeclámpticas, Md = 1.475 ñ 0.311 nanomolas que cuando fueron incubadas en suero de embarazadas normotensas, Md = 0.9725 ñ 0.58 nanomolas, p < 0.02. Este hallazgo sugiere que en el suero de las pacientes preeclámpticas existe algún factor que facilicita la entrada de calcio a la célula, que provoca un aumento en la concentración de calcio libre y participa en la hipertensión gestacional.