Who wins in the weaning process? Juvenile feeding morphology of two freshwater mussel species.

The global decline of freshwater mussels can be partially attributed to their complex life cycle. Their survival from glochidium to adulthood is like a long obstacle race, with juvenile mortality as a key critical point. Mass mortality shortly after entering into a juvenile state has been reported in both wild and captive populations, thus weakening the effective bivalve population. A similar phenomenon occurs during metamorphosis in natural and hatchery populations of juvenile marine bivalves. Based on a morphological analysis using scanning electron microscopy of newly formed juveniles of the freshwater species Margaritifera margaritifera (L.) (Margaritiferidae) and Unio mancus Lamarck (Unionidae), we show that a second metamorphosis, consisting of drastic morphological changes, occurs that leads to suspension feeding in place of deposit feeding by the ciliated foot. We hypothesize that suspension feeding in these two species improves due to a gradual development of several morphological features including the contact between cilia of the inner gill posterior filaments, the inner gill reflection, the appearance of the ctenidial ventral groove and the formation of the pedal palps. Regardless of the presence of available food, a suspension feeding mode replaces deposit feeding, and juveniles unable to successfully transition morphologically or adapt to the feeding changes likely perish.

[Slow processing in borderline personality disorder: the emotional Stroop paradigm]. / Lentificación del procesamiento de la información en el trastorno límite de la personalidad: el paradigma de Stroop emocional.

BACKGROUND: Emotional instability has been extensively considered the main core of the borderline personality disorder (BPD) that is characterised by an important bias towards emotional information. The aim of this study was to determine the emotional bias in patients with BPD by means of an emotional Stroop paradigm. SAMPLING AND METHODS: Sixty-one women (38 Borderline Personality Disorder outpatients and 23 healthy matched control subjects) were included. All of them underwent a computerised version of an emotional Stroop which included four valences: borderline-related negative, negative, positive and neutral. RESULTS: The results showed that BPD patients were slower in spotting the ink of the words [F(1.59)=4.33; p=0.04], and this effect was mainly for borderline-related and neutral words. Likewise, the more severe the BPD the slower the subjects [F(2.57)=4.81; p=0.012], indicating difficulties in processing information. CONCLUSIONS: The findings suggest that the emotional dysregulation may account for selective processing with emotional stimulus, which in turn triggers emotional responses in BPD patients, rather than to reflect a more general hypervigilance and an attentional bias for any kind of stimulus.

Lentificación del procesamiento de la información en el trastorno límite de la personalidad: el paradigma de Stroop emocional / Slow processing in borderline personality disorder: the emotional Stroop paradigm

Introducción. La inestabilidad emocional se considera la disfunción principal en el trastorno límite de la personalidad (TLP), que se caracteriza por un importante sesgo hacia la información emocional. El objetivo de este estudio fue determinar el sesgo emocional en pacientes con TLP mediante un paradigma de Stroop emocional. Muestra y Método. Se incluyeron en el estudio 61 mujeres (38 pacientes ambulatorias con TLP y 23 controles sanos apareados). Todos los sujetos realizaron una versión informatizada de un Stroop emocional que incluía palabras con cuatro valencias: palabras negativas con contenido límite, palabras negativas, palabras positivas y palabras neutras. Resultados. Los resultados indicaron que los pacientes con TLP era más lentos acertando el color de las palabras [F(1,59)=4,33; p=0,04], y este efecto se observaba principalmente en el caso de las palabras con contenido límite y de las palabras neutras. Además, los pacientes con mayor gravedad del trastorno eran más lentos [F(2,57)=4,81; p=0,012], lo que indica dificultades en el procesamiento de la información. Conclusiones. Los resultados obtenidos indican que la disregulación emocional podría explicarse por un procesamiento selectivo ante estímulos emocionales, lo que desencadenaría respuestas emocionales en los pacientes con TLP, mejor que por una hipervigilancia generalizada o por un sesgo atencional ante cualquier tipo de estímulo (AU)

Background. Emotional instability has been extensively considered the main core of the borderline personality disorder (BPD) that is characterised by an important bias towards emotional information. The aim of this study was to determine the emotional bias in patients with BPD by means of an emotional Stroop paradigm. Sampling and Methods. Sixty-one women (38 Borderline Personality Disorder outpatients and 23 healthy matched control subjects) were included. All of them underwent a computerised version of an emotional Stroop which included four valences: borderline-related negative, negative, positive and neutral. Results. The results showed that BPD patients were slower in spotting the ink of the words [F(1.59)=4.33; p=0.04], and this effect was mainly for borderline-related and neutral words. Likewise, the more severe the BPD the slower the subjects [F(2.57)=4.81; p=0.012], indicating difficulties in processing information. Conclusions. The findings suggest that the emotional dysregulation may account for selective processing with emotional stimulus, which in turn triggers emotional responses in BPD patients, rather than to reflect a more general hypervigilance and an attentional bias for any kind of stimulus (AU)

Specific and reversible inactivation of Phycomyces blakesleeanus isocitrate lyase by ascorbate-iron: role of two redox-active cysteines.

Phycomyces blakesleeanus isocitrate lyase (EC 4.1.3.1) is in vivo reversibly inactivated by hydrogen peroxide. The purified enzyme showed reversible inactivation by an ascorbate plus Fe(2+) system under aerobic conditions. Inactivation requires hydrogen peroxide; was prevented by catalase, EDTA, Mg(2+), isocitrate, GSH, DTT, or cysteine; and was reversed by thiols. The ascorbate served as a source of hydrogen peroxide and also reduced the Fe(3+) ions produced in a "site-specific" Fenton reaction. Two redox-active cysteine residues per enzyme subunit are targets of oxidative modification; one of them is located at the catalytic site and the other at the metal regulatory site. The oxidized enzyme showed covalent and conformational changes that led to inactivation, decreased thermal stability, and also increased inactivation by trypsin. These results represent an example of redox regulation of an enzymatic activity, which may play a role as a sensor of redox cellular status.