Abundance and spatial-temporal distribution of Macrobrachium surinamicum Holthuis, 1948 (Palaemonidae) in the Amazon estuary, north of Brazil.

Macrobrachium surinamicum is a small shrimp that inhabits rivers of low salinity. It is mainly caught as bycatch in Amazon shrimp Macrobrachium amazonicum fisheries, which is widely exploited by artisanal fisheries for food and economic needs of the riverside population. This study aimed to characterize the spatial and temporal distribution of the freshwater shrimp M. surinamicum in the Guajará Bay and on Mosqueiro Island, correlating the abundance of this species with abiotic factors (temperature and salinity). Samples were taken from May 2006 to April 2007 in six locations: Mosqueiro Island (Furo das Marinhas and Porto do Pelé); Icoaraci district; Arapiranga Island, edge of the city of Belém; and Combu Island, using traps named 'matapis'. A total of 361 shrimps were caught. The abundance was higher in December and lower in July 2006. The biggest catch occurred on Arapiranga Island and the lowest on Mosqueiro Island. The abundance differed significantly in December 2006 and no variable studied had significant influence on M. surinamicum abundance. In Guajará Bay, particularly the more sheltered places, as Arapiranga and Combu islands, favor the development of M. surinamicum, indicating that this species has preference for less disturbed areas.

Mathematical modelling of industrial pilot-plant penicillin-G fed-batch fermentations.

Penicillin-G fermentation with industrial media in 1 m3 stirred tank bioreactors was studied. A model based on the Bajpai-Reuss model structure was developed. Under typical production conditions catabolite repression is nonidentifiable and extensive mycelium differentiation occurs. Thus, the original model was reformulated, neglecting glucose repression of penicillin production and including biomass autolysis. The multi-substrate nature of industrial media was critically analysed. By combining the two most important carbon substrates present, a simple and applicable model was obtained. Model predictions agreed well with experimental data and reproduced the general characteristics observed in the fermentations. The predictive power of the model was tested for fermentations with different sugar feed rate profiles and raw materials (corn-steep liquor and sugar syrup). Several aspects of parameter estimation and model development are discussed on the basis of direct experimental data inspection and a sensitivity analysis of model parameters.

[Insulin resistance and evolution]. / Resistencia a la insulina y evolución.

Both infections and injuries activate the immunity system, leading to a series of metabolic changes which place the organism at a disadvantage and contribute to its elimination, thus facilitating the repair of the injured tissue. The study of the actions of tumour necrosing factor alpha (TNF-alpha) and interleukin-6 (IL-6), classically implicated in inflammatory processes and in fighting infection, has revealed numerous metabolic effects. Some gene polymorphisms of TNF-alpha and IL-6 (associated with a different TNF-alpha or IL-6 transcription rate) and the plasma concentrations of the soluble TNF-alpha receptor are found to be simultaneously associated with resistance to insulin, the proportion of body fat and with the mortality linked with different chronic infections. Therefore, it seems that the immune system is designed to fight infections effectively and to provide certain survival advantages during periods of intermittent fasting so frequent in the past. By inducing a resistance to insulin in the muscles, the energy substrates would thus be reserved for neuronal metabolism. In the presence of an insulin-resistance genotype and a westernization of the environment (carbohydrate-rich diet, an increase in saturated fat, low fibre and sedentary lifestyle), a genotype with a high cytokine response will contribute to a worsening of the resistance to insulin and, finally, to type 2 diabetes mellitus and atherosclerosis. The advantages for our ancestors of a large cytokine response (eradication of the lesion) or moderate resistance to insulin (protection against food shortage) have led in the present day to the development of atherosclerosis now that the characteristics of the environment have changed. It is contended that these changes constitute examples of good adaptation to the environment or poor concordance between our current lifestyle and our genome.

[Adipsia and hypernatremia as the first manifestation of hypothalamic astrocytoma. Report of a case and review of the literature]. / Adipsia e hipernatremia como primera manifestación de un astrocitoma hipotalámico. Descripción de un caso y revisión de la literatura.

Adipsia and hypernatremia is a syndrome which can be observed among children and adults with various congenital or acquired diseases of the brain. We can include the primary neoplasms and the metastatic among the causes of this syndrome. We display the case of a 63-year-old man who presented time-space disorientation, loss of memory fixation, visual hallucinations, unstable walking and absence of the voluntary ingestion of liquids. The serum electrolytes showed serum sodium concentration of 188 mEq/l with plasma osmolality above 380 mOs/kg. Both the forced water intake and the intravenous rehydration restored the plasma osmolality and the normal levels of serum sodium. The magnetic resonance (MR) neurohypophyseal area showed a neoformative lesion at the middle line which affected septum ventricular and hypothalamic area. We analyse the pathophysiologic mechanisms, the clinical and laboratory data, as well as the therapeutic and the evolution of the cases which have been published in the literature.

Local identifiability and sensitivity analysis of neuromuscular blockade and depth of hypnosis models.

This paper addresses the local identifiability and sensitivity properties of two classes of Wiener models for the neuromuscular blockade and depth of hypnosis, when drug dose profiles like the ones commonly administered in the clinical practice are used as model inputs. The local parameter identifiability was assessed based on the singular value decomposition of the normalized sensitivity matrix. For the given input signal excitation, the results show an over-parameterization of the standard pharmacokinetic/pharmacodynamic models. The same identifiability assessment was performed on recently proposed minimally parameterized parsimonious models for both the neuromuscular blockade and the depth of hypnosis. The results show that the majority of the model parameters are identifiable from the available input-output data. This indicates that any identification strategy based on the minimally parameterized parsimonious Wiener models for the neuromuscular blockade and for the depth of hypnosis is likely to be more successful than if standard models are used.

Abundance and spatial-temporal distribution of Macrobrachium surinamicum Holthuis, 1948 (Palaemonidae) in the Amazon estuary, north of Brazil / Abundância e distribuição espaço-temporal de Macrobrachium surinamicum Holthuis, 1948 (Palaemonidae) em um estuário Amazônico, norte do Brasil

Abstract Macrobrachium surinamicum is a small shrimp that inhabits rivers of low salinity. It is mainly caught as bycatch in Amazon shrimp Macrobrachium amazonicum fisheries, which is widely exploited by artisanal fisheries for food and economic needs of the riverside population. This study aimed to characterize the spatial and temporal distribution of the freshwater shrimp M. surinamicum in the Guajará Bay and on Mosqueiro Island, correlating the abundance of this species with abiotic factors (temperature and salinity). Samples were taken from May 2006 to April 2007 in six locations: Mosqueiro Island (Furo das Marinhas and Porto do Pelé); Icoaraci district; Arapiranga Island, edge of the city of Belém; and Combu Island, using traps named 'matapis'. A total of 361 shrimps were caught. The abundance was higher in December and lower in July 2006. The biggest catch occurred on Arapiranga Island and the lowest on Mosqueiro Island. The abundance differed significantly in December 2006 and no variable studied had significant influence on M. surinamicum abundance. In Guajará Bay, particularly the more sheltered places, as Arapiranga and Combu islands, favor the development of M. surinamicum, indicating that this species has preference for less disturbed areas.

Resumo Macrobrachium surinamicum é um camarão de pequeno porte que habita a foz de rios e águas de baixa salinidade. Sua captura na Amazônia ocorre principalmente como fauna associada à pesca do camarão-da-Amazônia Macrobrachium amazonicum que é largamente explorado pela pesca artesanal atendendo as necessidades alimentícias e econômicas da comunidade ribeirinha. O presente estudo teve como objetivo caracterizar a distribuição espaço-temporal do camarão dulcícola M. surinamicum na Baía do Guajará e Ilha de Mosqueiro, correlacionando a abundância desta espécie com fatores abióticos (temperatura e salinidade). Os exemplares foram capturados no período de maio/06 a abril/07 em seis locais: Ilha de Mosqueiro (Furo das Marinhas e Porto do Pelé), Distrito de Icoaraci, Ilha do Arapiranga, orla de Belém e Ilha do Combu com armadilhas (matapis). Um total de 361 camarões foi capturado, sendo a maior abundância em dezembro e a menor em julho de 2006. A maior captura foi na Ilha de Arapiranga e a menor na Ilha de Mosqueiro. A abundância diferiu significativamente em dezembro/06 e nenhuma variável estudada teve influência significativa na abundância de M. surinamicum. A Baía do Guajará, especialmente os locais mais abrigados como a Ilha de Arapiranga e do Combu, propiciam o desenvolvimento de M. surinamicum, o que indica que esta espécie tenha preferência para áreas menos antropizadas.

Model predictive control of depth of anaesthesia: guidelines for controller configuration.

The paper presents a feasibility study on the use of Model based Predictive control (MPC) to regulate the level of Depth of Anaesthesia (DoA) when measured by the BIS index. Pharmacokinetic/pharmacodynamic nonlinear models of DoA when Propofol and Remifentanil are used as hypnotic and analgesic drugs are linearized around the desired working point for DoA in order to obtain a linear state-space model coupled with an extra integrator to include integral action in the control. This state-space model is then used in a MPC algorithm. The main contribution of the paper consists in the characterization of the influence of the different design parameters in the MPC performance when controlling DoA.

A target control Infusion method for neuromuscular blockade based on hybrid parameter estimation.

The paper presents a new method for target control infusion (TCI) for neuromuscular blockade (NMB) level control of patients subject to general anaesthesia. The method combines an inversion of the pharmacokinetic/pharmacodynamic (PK/PD) model with a hybrid parameter estimation method that uses on-line data from the initial bolus response to estimate the model parameters. Although atracurium is considered as relaxant, the newly proposed method may be applied to other drugs for which the PK/PD model is available. Simulation results on a bank of 100 patient models are presented to demonstrate the achievable performance.

Paralysis in the critically ill: intermittent bolus pancuronium compared with continuous infusion.

OBJECTIVES: To compare recovery times from neuromuscular blockade between two groups of critically ill patients in whom pancuronium was administered by continuous infusion or intermittent bolus injection. To compare the mean pancuronium requirements (milligrams per kilogram per hour) and to assess the incidence of prolonged recovery times (>12 hrs) and residual muscle weakness. DESIGN: Prospective, observational cohort. SETTING: Intensive care unit in a university-affiliated hospital. PATIENTS: A total of 30 mechanically ventilated patients who required pharmacologic paralysis. Patients were excluded if they had renal failure (creatinine clearance <30 mL/min), heart rate >130 beats/min, hepatic failure, peripheral nerve disease or myopathy, stroke, spinal cord damage, or myasthenia gravis. INTERVENTIONS: Patients were assigned to receive pancuronium either by continuous infusion (n = 14) or intermittent bolus (n = 16). Depth of paralysis was titrated to maintain one or two responses to Train-of-Four stimulation with an accelerograph and desired clinical goals. Recovery time was defined as time from discontinuation of muscle relaxant until the amplitude of the fourth twitch, measured every 15-30 min using an accelerograph, was 70% the amplitude of the first twitch (Train-of-Four > or = 0.7). MEASUREMENTS AND MAIN RESULTS: These patients included the only three patients with status asthmaticus in our study. The groups were similar with respect to age, sex, weight, Acute Physiology and Chronic Health Evaluation II score, mode of ventilation, creatinine clearance, indications for paralysis, and duration of pancuronium administration. The median time for patients to recover from paralysis was 3.5 hrs (95% confidence interval, 1.82-5.18) in the infusion group vs. 6.3 hrs (95% confidence interval, 3.40-9.19) in the intermittent bolus group (p = .10). Less drug was administered in the intermittent group (mean, 0.02+/-0.01 mg/kg/hr) than by infusion (mean, 0.04+/-0.01 mg/kg/hr; p < .001). Six patients (five in the infusion group and one in the intermittent group) developed persistent severe muscle weakness. In addition, six different patients (three from each group) had prolonged recovery >12 hrs. CONCLUSIONS: Our study suggests that recovery time after paralysis with continuous infusion is faster than that after intermittent bolus injection. Although more pancuronium was administered in the continuous-infusion group, recovery time was not prolonged as a consequence. It is uncertain whether pancuronium given by infusion increases the risk of persistent muscle weakness.

Estudo das lesöes pulmonares de suínos de abate / Lung lesions studies in swine at slaughter house

Realizaram-se dois experimentos com o objetivo de se estudar as lesöes pulmonares de suínos de abate. No experimento A, foram examinados, 3343 suínos abatidos em frigoríficos da grande Belo Horizonte, MG, em 1988. De um total de 658 animais, foram registradas 891 lesöes, assim identificadas: hepatizaçäo pulmonar (53,9 por cento), pleurisia (35,7 por cento), abscessos (6,5 por cento) e pericardite (3,9 por cento). Os lobos cardíacos foram os mais afetados pela hepatizaçäo (44,3 por cento) e abscessos (56,7 por cento). As pleurisias foram mais frequentes nos lobos diafragmáticos direitos (23,7 por cento) e cardíacos (23,0 por cento). No experimento B foi determinado o escore pulmonar de 11 granjas de MG, utilizando-se 2006 suínos. Seis granjas apresentaram escore pulmonar variando de 1,45 a 2,60, enquanto outras cinco apresentaram escore pulmonar de 0,07 a 0,23. O ganho de peso diário (GPD), do nascimento ao abate variou de 573g a 649g nas 11 granjas estudadas (média de 604,8g). Nas granjas com escore pulmonar acima de 1,0, a variaçäo do GPD foi de 560 a 630g (média de 584,4g) aos 147 dias de idade, enquanto nas granjas com escore pulmonar abaixo de 1,0 o GPD variou de 600g a 648g (média de 626,8g) aos 143,4 dias de idade