Valoración de impacto ambiental en el Puerto Moa-Holguín / Environmental impact assessment in Moa-Holguín Port

Las operaciones de descarga de los buques-tanques, la recepción y distribución de productos derivados del crudo de petróleo en el área de almacenamiento, el movimiento de insumos como el carbón antracita, amoniaco y azufre, la carga de lotes de minerales así como el mantenimiento de los tanques, conducen al vertimiento directo de hidrocarburos que afectan los diferentes ecosistemas en los cuales se encuentra situada la fuente contaminante. Se presenta la caracterización de los ecosistemas afectados por esta contaminación, atendiendo a los impactos ambientales identificados y la previa caracterización del área, utilizando herramientas de evaluación de criterios de expertos mediante la metodología Delphi. El estudio de impacto ambiental se realizó de forma cualitativa a través de las matrices causa-efecto, valoración e importancia del impacto. Los factores del medio más afectado fueron las aguas superficiales y subterráneas y la salud e higiene; las acciones más agresivas fueron la emisión de contaminantes (vertimiento al medio suelo de hidrocarburos/ liberación al medio aire de gases, ruidos y materiales particulados/ vertimiento y contaminación del acuatorio por arrastres de sedimentos, hidrocarburos y sustancias químicas) y la acumulación de residuos (creación de vertederos industriales).

The operations of unloading ships the reception and distribution of products derivate of oil crude in the storage area, the movement of raw materials like coal anthracite, ammonia and sulphur, the load of lots of minerals as well as the maintenance of ships, direct leads to the appearance of hydrocarbons that affects the different ecosystems which he meets in once the contaminating source in the municipal Moa. It is present the characterization of ecosystems affected with oil's hydrocarbons, attending to environmental impacts identified by the expert group and the prior characterization of the area using assessment tools expert judgment using Delphi methodology. The environmental impact study was realized of qualitative form through matrix of cause-effect, valuation and importance of impact. The environmental factors of resulting surface/groundwater and health and hygiene the most attacked while impacts were more aggressive emissions (throwing to the ground hydrocarbons/ liberation to the midway air of gases, noises and materials in particles, throwing and contamination of the source for dragging of sediments, hydrocarbons and chemical substances) and accumulation waste (creation of drains industrials).

Diagnóstico de pseudotuberculosis en ovinos patagónicos / Diagnosis of caseous lymphadenitis in sheep from Patagonia

La linfadenitis caseosa (LAC) es una enfermedad bacteriana supurativa crónica que afecta a ovinos. El agente etiológico es Corynebacterium pseudotuberculosis. El diagnóstico diferencial con otras afecciones que presentan manifestaciones clínicas similares sólo puede hacerse sobre la base del aislamiento y la identificación del agente etiológico. El objetivo de este trabajo fue caracterizar metabólica y genéticamente al agente causal de abscesos granulomatosos observados en ovinos en la región patagónica. En las muestras, se observó un contenido caseoso rodeado de una membrana fibrosa, y en el examen histopatológico, un centro de necrosis caseosa rodeado por células epitelioides, linfocitos y polinucleares. Mediante estudios microscópicos, bacteriológicos y moleculares fue confirmada la infección causada por C. pseudotuberculosis biovar ovis.

Caseous lymphadenitis (CLA) is a chronic bacterial, infectious and contagious disease caused by Corynebacterium pseudotuberculosis. It affects sheep and results in abscesses of the lymph nodes in subcutaneous tissue, as well as in internal organs such as lungs, liver and kidneys. Differential diagnosis of the disease is based on the isolation and biochemical identification of the etiological agent. The purpose of this study was to characterize the bacteria isolated from typical CLA lesions in sheep from Patagonia, Argentina, at metabolic and genetic levels. Macroscopic observations show a fibrous membrane containing caseous necrotic tissue. Histopathological analysis shows an eosinophilic necrotic area surrounded by epitheloid cells and polymorphonuclear infiltration. Other analyses performed such as microscopic observations, in vitro culture, biochemical tests and 16s rDNA sequencing confirmed diagnosis of caseous lymphadenitis due to C. pseudotuberculosis.

Enhanced biodegradation of Casablanca crude oil by a microbial consortium in presence of a rhamnolipid produced by Pseudomonas aeruginosa AT10.

The biodegradation of oil products in the environment is often limited by their low water solubility and dissolution rate. Rhamnolipids produced by Pseudomonas aeruginosa AT10 were investigated for their potential to enhance bioavailability and hence the biodegradation of crude oil by a microbial consortium in liquid medium. The characterization of the rhamnolipids produced by strain AT10 showed the effectiveness of emulsification of complex mixtures. The addition of rhamnolipids accelerates the biodegradation of total petroleum hydrocarbons from 32% to 61% at 10 days of incubation. Nevertheless, the enhancement of biosurfactant addition was more noticeable in the case of the group of isoprenoids from the aliphatic fraction and the alkylated polycyclic aromatic hydrocarbons (PHAS) from the aromatic fraction. The biodegradation of some targeted isoprenoids increased from 16% to 70% and for some alkylated PAHs from 9% to 44%.

The nature of spontaneous recovery from mivacurium-induced neuromuscular block.

UNLABELLED: The hypothesis of this study was that, in a given patient, recovery from a tracheal intubating dose of mivacurium would indicate the time course of spontaneous recovery after discontinuation of an infusion of mivacurium. Thirty-eight male patients consented to participate in the study. After induction of anesthesia and endotracheal intubation, the ulnar nerve was stimulated with train-of-four (TOF) stimuli at 12-s intervals. Patients received 0.3 mg/kg mivacurium in two evenly divided doses of 0.15 mg/kg each, separated by 30 s. Complete ablation of TOF responses occurred in most patients. Once the first twitch in the TOF (T ) had recovered to 25% of its baseline height, a mivacurium infusion was begun to maintain 95% suppression of T1. As surgery was nearing completion, the infusion was discontinued, and neuromuscular function was allowed to recover spontaneously. Data were analyzed for recovery intervals after the administration of the initial doses of mivacurium and after discontinuation of the infusion. Analysis of variance was used to determine the strength of correlation between the time from administration of the initial 0.3 mg/kg dose to 5% recovery of T1 and the times to recovery of TOF ratios of 70% and 90%. The 25%-75% recovery interval after discontinuation of the infusion ranged from 2.8 to 11.3 min. The time interval after administration of mivacurium 0.3 mg/kg to 5% recovery of T1 correlated with both the time to recovery of a TOF ratio of 70% and 90%. Recovery to a TOF of 90% after discontinuation of the infusion required approximately the same amount of time as recovery to 5% T1 after the administration of 0.3 mg/kg mivacurium. Each patient's recovery of neuromuscular function after discontinuation of a mivacurium infusion was related to his recovery after the administration of 0.3 mg/kg mivacurium. Therefore, the need for pharmacologic antagonism of block can be anticipated well before the end of an anesthetic. IMPLICATIONS: Mivacurium (0.3 mg/kg) was administered to 38 patients. As they began to recover muscle strength, a mivacurium infusion was begun and later discontinued as surgery was nearing completion. Each patient's early recovery (administration to 5% recovery of T1) after the initial dose of mivacurium correlated well with more complete recovery of muscle strength after discontinuation of an infusion. This relationship enables early prediction of recovery speed after a mivacurium infusion.

A comparison: the efficacy of sevoflurane-nitrous oxide or propofol-nitrous oxide for the induction and maintenance of general anesthesia.

STUDY OBJECTIVE: To compare sevoflurane-nitrous oxide with propofol-nitrous oxide for the induction and maintenance of anesthesia, and to determine the rates of recovery following each anesthetic. DESIGN: Randomized, controlled study. SETTING: Teaching hospital. PATIENTS: 50 ASA physical status I and II patients, ranging in age from 18 to 70 years. INTERVENTIONS: General anesthesia was induced with either sevoflurane or propofol and maintained with 60% to 70% nitrous oxide and either sevoflurane or a propofol infusion and supplemental fentanyl. At the conclusion of surgery, the oxygen flow was increased to 6 L/min and all anesthetics were discontinued simultaneously. Patients were monitored for the nature and speed of induction and emergency from anesthesia. MEASUREMENTS AND MAIN RESULTS: Induction of anesthesia was significantly slower in the sevoflurane group than in the propofol group (2.0 +/- 1.1 vs. 0.8 +/- 0.5 min, respectively). The ease of induction and the time required for emergence from anesthesia were the same in both study groups (eye opening: 9.0 +/- 4.4 min vs. 8.0 +/- 5.0 min; following commands: 11.2 +/- 5.0 min vs. 9.8 +/- 6.9 min; extubation: 9.1 +/- 4.5 min vs. 8.6 vs. 5.1 min in the sevoflurane and propofol groups, respectively). Patients in the sevoflurane group experienced nausea and vomiting more frequently than patients in the propofol group (13 and 5 patients vs. 3 and 0 patients in the sevoflurane and propofol groups, respectively), which were not related to the administration of neostigmine or intraoperative opioids. CONCLUSION: Sevoflurane allows for rapid inhalation induction of, and emergence from, general anesthesia.

Pharmacokinetics of cisatracurium in patients receiving nitrous oxide/opioid/barbiturate anesthesia.

BACKGROUND: Cisatracurium, one of the ten isomers in atracurium, is a nondepolarizing muscle relaxant with an intermediate duration of action. It is more potent and less likely to release histamine than atracurium. As one of the isomers composing atracurium, it presumably undergoes Hofmann elimination. This study was conducted to describe the pharmacokinetics of cisatracurium and its metabolites and to determine the dose proportionality of cisatracurium after administration of 2 or 4 times the ED(95). METHODS: Twenty ASA physical status 1 or 2 patients undergoing elective surgery under nitrous oxide/opioid/barbiturate anesthesia were studied. Patients received a single rapid intravenous bolus does of 0.1 or 0.2 mg x kg-1 (2 or 4 times the ED(95), respectively) cisatracurium. All patients were allowed to recover spontaneously to a train-of-four ratio > or = 0.70 after cisatracurium-induced neuromuscular block. Plasma was extracted, acidified, and stored frozen before analysis for cisatracurium, laudanosine, the monoquaternary acid, and the monoquaternary alcohol metabolite. RESULTS: The clearances (5.28 +/- 1.23 vs. 4.66 +/- 0.67 ml x min(-1) x kg(-1) and terminal elimination half-lives (22.4 +/- 2.7 vs. 25.5 +/- 4.1 min) were not statistically different between patients receiving 0.1 mg x kg(-1) and 0.2 mg x kg(-1), respectively. Maximum concentration values for laudanosine averaged 38 +/- 21 and 103 +/- 34 ng x ml(-1) for patients receiving the 0.1 and 0.2 mg x kg(-1) doses, respectively. Maximum concentration values for monoquaternary alcohol averaged 101 +/- 27 and 253 +/- 51 ng x ml(-1), respectively. Monoquaternary acid was not quantified in any plasma sample. CONCLUSIONS: Cisatracurium undergoes Hofmann elimination to form laudanosine. The pharmacokinetics of cisatracurium are independent of dose after single intravenous doses of 0.1 and 0.2 mg x kg(-1).

Abnormal coagulation profile in brain tumor patients during surgery.

Neurosurgical patients are at high risk for the development of thrombosis and thromboembolism. We compared the perioperative clotting factor and coagulation parameters of 20 patients undergoing elective craniotomy for brain tumors to those of 20 patients undergoing elective abdominal surgery. We also measured the levels of plasma arginine vasopressin to determine if changes in this hormone might be associated with changes in clotting factors, activated partial thromboplastin times, or bleeding times. The results demonstrated a significant reduction in partial thromboplastin times and bleeding times in the neurosurgery group, which began at the initiation of surgery and lasted to the end of the study (12 h postoperatively). Elevations in factor assays and plasma arginine vasopressin occurred in both groups during surgery, but there were no differences between the neurosurgical and abdominal surgical patients, except with Factor IX levels, which were elevated only in the neurosurgical patients. Serum osmolality and hemoglobin levels were significantly higher in the neurosurgical cohort. These results suggest that there are hemostatic differences between neurosurgical patients with brain tumors and abdominal surgery patients that cannot be explained solely by elevations in plasma arginine vasopressin or the clotting factors measured; these differences may be the consequence of perioperative variables such as dehydration and hyperosmolality.

Myocardial ischemia during the weaning period.

OBJECTIVES: To estimate the incidence of silent myocardial ischemia, its pattern over time and its relationship to the time and mode of weaning high-risk cardiac patients after noncardiac surgery. DESIGN: Prospective study with random assignment to one of three weaning modes. SETTING: A surgical intensive care unit in a university hospital and a Veterans Administration hospital. PATIENTS: Sixty-two patients meeting standard criteria for extubation were randomized to one of three modes of weaning: synchronized intermittent mandatory ventilation (n = 19), T-Bar (n = 21) or continuous positive airway pressure (n = 22). METHODS: Ischemia was monitored with a continuous two-lead (V5, III) ST segment analyzer. Tracings were reviewed by a cardiologist. Ischemia was defined as greater than 1 mm ST segment depression 60 milliseconds after the J point. The monitoring period included a prewean (mean 654.0 minutes), wean (mean 46.5 minutes) and postwean (mean 1223.4 minutes) period. RESULTS: Of 62 patients, 12 (19.3%) experienced ischemia at some time during the monitoring period, most often during the weaning period. Ischemia during weaning was detected in 3 of 21 (14.3%) T-Bar patients and 2 of 22 (9.1%) continuous positive airway pressure patients but in no synchronized intermittent mandatory ventilation patients. CONCLUSION: This study demonstrates that silent myocardial ischemia occurs frequently in high-risk postoperative patients, with the highest incidence during weaning.