Contracaecum multipapillatum (Nematoda: Anisakidae) en peces de aguas continentales de Guanacaste, Costa Rica e Izabal, Guatemala

Contracaecum multipapillatum infects fish as intermediate hosts and humans as accidental hosts when consuming raw or semi-cooked fish meat, causing Contracecosis. This risk to human health makes important to determine prevalence, infection intensity and anatomical location in fish for human consumption through artisanal fishing; and the physicochemical parameters influence of water on infection in fish. 214 fish were collected in 6 rivers from Cañas, Guanacaste, Costa Rica and 203 fish in Izabal Lake and Río Dulce, Izabal, Guatemala. Water physicochemical parameters (temperature, pH and dissolved oxygen) were taken at fishing sites. The infection prevalence was 16.8% and 25.1% in Guanacaste and Izabal, respectively, 36 fish were found infected with 105 larvae of the third stage (L3) in Guanacaste and 135 larvae were found in 51 infected fish in Izabal. A higher affinity of L3 was observed in visceral organs (22.4% in Guanacaste - 25.1% in Izabal) and lower affinity in muscle tissue (2.0% in Guanacaste – 1.0% in Izabal). Infection intensity was proportional to the size and weight fish (1 larva in 13 fish with average weight and size of 66.7 g and 17.5 cm in Guanacaste, and in 7 fish with weight and average size of 214.9 g and 28.4 cm in Izabal; while 14 larvae were found in a fish of 148.8 g and 24 cm in Guanacaste and 12 larvae in a fish of 260g and 40 cm in Izabal). No association was observed between the water physicochemical parameters and the fish susceptibility to infection.Contracaecum multipapillatum infecta peces como hospedadores intermediarios y al ser humano como hospedador accidental por consumo de carne de pescado cruda o semi cocinada. Este riesgo para la salud humana hace importante determinar su prevalencia, intensidad de infección y ubicación anatómica en peces destinados al consumo mediante pesca artesanal; y la influencia de parámetros físicoquímicos del agua sobre la infección en peces. Se recolectaron 214 peces en 6 ríos de Cañas, Guanacaste, Costa Rica y 203 peces en el Lago de Izabal y Río Dulce, Izabal, Guatemala. En los sitios de pesca se tomaron parámetros físicoquímicos del agua (temperatura, pH y oxígeno disuelto). La prevalencia de infección fue 16.8% y 25.1% en Guanacaste e Izabal, respectivamente, encontrándose 105 larvas de tercer estadio (L3) en 36 peces de Guanacaste y 135 L3 en 51 peces de Izabal. Se observó afinidad de L3 por órganos viscerales (22.4% en Guanacaste – 25.1% en Izabal) y menor por tejido muscular (2.0% en Guanacaste – 1.0% en Izabal). La intensidad de infección directamente proporcional con la talla y peso de los peces (una larva en 13 peces con peso y talla media de 66.7 g y 17.5 cm en Guanacaste, y siete peces de 214.9 g y 28.4 cm en Izabal; y 14 larvas en un pez de 148.8 g y 24 cm en Guanacaste y 12 larvas en un pez de 260 g y 40 cm en Izabal). No se observó asociación entre parámetros fisicoquímicos del agua y susceptibilidad de peces a infección

Is cytochrome aa3 from thermus thermophilus a single subunit oxidase?

A reliable procedure has been developed for the purification of the cytochrome c1aa3 complex from the plasma membrane of T. thermophilus. The ratios heme C:heme A:Fe:C were found to be 1:2:3:2 confirming previous results, however, the molecular weight was found to be ~92,000 rather than the ~200,000 reported earlier [1]. Polyacrylamide gel electrophoresis under strongly denaturing conditions and high performance reverse phase liquid chromatography showed that cytochrome c1aa3 is composed of only two subunits in 1:1 ratio. Both polypeptides have blocked N-termini. The smaller subunit (~33,000) binds heme c and presumably no other metals. The larger subunit (~55,000) is thus thought to contain the elements of cytochrome aa3 and therefore be considered a single subunit cytochrome oxidase.The bacterial cytochrome c1aa3 has been compared with beef heart cytochrome oxidase with a number of techniques including optical, EPR [1], Raman, MCD, and Mossbauer [2] spectroscopies. These experiments establish that the fundamental chemical properties of the redox centers are substantially similar in these two proteins.Cytochrome c552 (from Thermus), horse heart cytochrome c, and tetramethylphenylenediamine greatly stimulate the ascorbate oxidase activity of cytochrome c1aa3. This enhancement is characterized by a `high affinity' component which results in only a small velocity increase and a `low affinity' component which gives a large velocity increase. Very similar behavior has been previously observed with mammalian cytochrome oxidase [3].Preliminary experiments show that vesicularized c1aa3 is capable of proton pumping.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25363/1/0000811.pd

Vascular hyperintensities on baseline FLAIR images are associated with functional outcome in stroke patients with successful recanalization after mechanical thrombectomy

International audiencePURPOSE: The purpose of this study was to assess the prognostic value of vascular hyperintensities on FLAIR images (VHF) at admission MRI in patients with acute ischemic stroke (AIS) achieving successful recanalization after mechanical thrombectomy. MATERIALS AND METHODS: Patients with AIS treated by mechanical thrombectomy following admission MRI from the single-center HIBISCUS-STROKE cohort were assessed for eligibility. VHF were categorized using a four-scale classification and were considered poor when grade \textless 3 (i.e., absence of distal VHF). Recanalization was considered successful when modified thrombolysis in cerebral infarction score was ≥ 2B Functional outcome was considered poor if modified Rankin scale (mRS) at three months was \textgreater 2. Univariable and multiple variable logistic regressions were performed to identify factors associated with poor functional outcome despite successful recanalization. RESULTS: A total of 108 patients were included. There were 65 men and 43 women with a median age of 70.5 years (interquartile range: 55.0, 81.0; age range: 22.0-93.0 years). Among them, 39 subjects (36.1%) had poor functional outcome at three months. Univariable logistic regressions indicated that poorly extended VHF (VHF grade \textless 3) were associated with a poor functional outcome (P = 0.008) as well as age, hypertension and diabetes, baseline National Institute of Health Stroke Scale (NIHSS) score, pre-stroke mRS, lack of intravenous thrombolysis, cerebral microangiopathy and the presence of microbleeds. Multivariable analysis confirmed that poor VHF status was independently associated with a poor functional outcome (odds ratio [OR], 4.26; 95% confidence interval [CI]: 1.55-12.99; P = 0.007) in combination with hypertension (OR, 1.25; 95% CI: 0.87-1.85; P = 0.02), baseline NIHSS score (OR, 1.09; 95% CI: 1.04-1.20; P = 0.03), pre-stroke mRS (OR, 2.05; 95% CI: 1.07-4.61; P = 0.05) and lack of intravenous thrombolysis (OR, 0.23; 95% CI: 0.08-0.61; P = 0.004). CONCLUSION: Poorly extended VHF (grade \textless3) at admission MRI are associated with a poor functional outcome at three months despite successful recanalization by mechanical thrombectomy