Trombosis del ligamento redondo del hígado asociado a colangitis aguda / Thrombosis of the hepatic round ligament associated with acure cholangitis

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Influence of simultaneous liver and peritoneal resection on postoperative morbi-mortality and survival in patients with colon cancer treated with surgical cytoreduction and intraperitoneal hyperthermic chemotherapy. / Influencia de la resección hepática y peritoneal simultánea, en la morbimortalidad y supervivencia de los pacientes con cáncer de colon intervenidos mediante cirugía citorreductora con quimioterapia intraperitoneal hipertérmica.

INTRODUCTION: Cytoreductive surgery plus intraperitoneal hyperthermic chemotherapy (HIPEC) has recently been established as the treatment of choice for selected patients with peritoneal carcinomatosis of colonic origin. Until recently, the simultaneous presence of peritoneal and hepatic dissemination has been considered a contraindication for surgery. The aim of this paper is to analyze the morbidity, mortality and survival of patients with simultaneous peritoneal and hepatic resection with HIPEC for peritoneal carcinomatosis secondary to colon cancer. METHODS: Between January 2010 and January 2015, 61 patients were operated on, 16 had simultaneous peritoneal and hepatic dissemination (group RH+), and 45 presented only peritoneal dissemination (group RH-). RESULTS: There were no differences between the groups in terms of demographic data, length of surgery and extension of peritoneal disease. Postoperative grade III-V complications were significantly higher in the RH+ group (56.3 vs. 26.6%; P=.032). For the whole group, mortality rate was 3.2% (two patients in group RH-, and none in group RH+). Patients with liver resection had a longer postoperative stay (14.4 vs. 23.1 days) (P=.027). Median overall survival was 33 months for RH-, and 36 for RH+ group. Median disease-free survival was 16 months for RH-, and 24 months for RH+ group. CONCLUSIONS: Simultaneous peritoneal cytoreduction and hepatic resection resulted in a significantly higher Clavien grade III-V morbidity and a longer hospital stay, although the results are similar to other major abdominal interventions. The application of multimodal oncological and surgical treatment may obtain similar long-term survival results in both groups.

Influencia de la resección hepática y peritoneal simultánea, en la morbimortalidad y supervivencia de los pacientes con cáncer de colon intervenidos mediante cirugía citorreductora con quimioterapia intraperitoneal hipertérmica / Influence of simultaneous liver and peritoneal resection on postoperative morbi-mortality and survival in patients with colon cancer treated with surgical cytoreduction and intraperitoneal hyperthermic chemotherapy

INTRODUCCIÓN: La citorreducción con quimioterapia intraperitoneal hipertérmica (HIPEC) se ha postulado como tratamiento de elección en pacientes seleccionados con carcinomatosis peritoneal por cáncer de colon. La presencia simultánea de diseminación peritoneal y hepática ha sido considerada una contraindicación para esta cirugía. El objetivo del presente estudio es analizar la morbimortalidad y supervivencia de los pacientes con carcinomatosis peritoneal por cáncer de colon, intervenidos mediante una citorreducción peritoneal y resección hepática simultánea con HIPEC. MÉTODOS: Entre enero de 2010 y enero de 2015 se intervinieron 61 pacientes, 45 pacientes con carcinomatosis peritoneal (grupo RH−) y 16 con carcinomatosis peritoneal y metástasis hepáticas (grupo RH+). RESULTADOS: No hubo diferencias significativas entre los 2grupos en los datos demográficos, ASA, duración de la intervención, ni extensión de la enfermedad peritoneal. Las complicaciones postoperatorias Clavien III-V fueron significativamente superiores en el grupo RH+ (56,3 vs. 26,6%; p = 0,03). La mortalidad global de la serie fue del 3,2% (2 pacientes en el grupo RH− y ninguno en el grupo RH+). Los pacientes con resección hepática presentaron una estancia hospitalaria significativamente más larga (14,4 vs. 23,1 días; p = 0,027). La mediana estimada de supervivencia global fue de 33 meses para RH− y de 36 meses para RH+, y la de supervivencia libre de enfermedad fue de 16 meses para RH− y de 24 para RH+. CONCLUSIONES: La citorreducción peritoneal con resección hepática simultánea presenta una morbilidad postoperatoria y una estancia hospitalaria significativamente mayores, aunque las cifras son similares a las de otras cirugías abdominales mayores. La aplicación de un tratamiento oncológico y quirúrgico multimodal permite obtener resultados de supervivencia similares en ambos grupos

INTRODUCTION: Cytoreductive surgery plus intraperitoneal hyperthermic chemotherapy (HIPEC) has recently been established as the treatment of choice for selected patients with peritoneal carcinomatosis of colonic origin. Until recently, the simultaneous presence of peritoneal and hepatic dissemination has been considered a contraindication for surgery. The aim of this paper is to analyze the morbidity, mortality and survival of patients with simultaneous peritoneal and hepatic resection with HIPEC for peritoneal carcinomatosis secondary to colon cancer. METHODS: Between January 2010 and January 2015, 61 patients were operated on, 16 had simultaneous peritoneal and hepatic dissemination (group RH+), and 45 presented only peritoneal dissemination (group RH−). RESULTS: There were no differences between the groups in terms of demographic data, length of surgery and extension of peritoneal disease. Postoperative grade III-V complications were significantly higher in the RH+ group (56.3 vs. 26.6%; P=.032). For the whole group, mortality rate was 3.2% (two patients in group RH−, and none in group RH+). Patients with liver resection had a longer postoperative stay (14.4 vs. 23.1 days) (P=.027). Median overall survival was 33 months for RH−, and 36 for RH+ group. Median disease-free survival was 16 months for RH−, and 24 months for RH+ group. CONCLUSIONS: Simultaneous peritoneal cytoreduction and hepatic resection resulted in a significantly higher Clavien grade III-V morbidity and a longer hospital stay, although the results are similar to other major abdominal interventions. The application of multimodal oncological and surgical treatment may obtain similar long-term survival results in both groups

Shunt portocava o malformación de Abernethy / Porto-caval shunt or Abernethy malformation

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La influencia del tiempo libre en el desarrollo Evolutivo adolescente / No disponible

La etapa de la adolescencia ha suscitado un gran interés en la psicología evolutiva y prueba de ello son las numerosas publicaciones científicas que se pueden encontrar en la actualidad sobre este periodo de la vida. En el desarrollo adolescente cobra una gran importancia el tiempo libre, un contexto socializador transversal a la escuela, la familia y los iguales, un contexto informal donde también se producen aprendizajes de valores y actitudes, de competencias y habilidades, hábitos y formas de relación y donde se contribuye a la satisfacción de necesidades psicológicas. La teoría de la autodeterminación constituye un modelo explicativo de la motivación humana que se puede aplicar al estudio de las repercusiones que tienen las actividades de tiempo libre en el desarrollo saludable y en el bienestar de los adolescentes. En nuestro país la literatura científica sobre el uso del tiempo de los adolescentes es escasa y los trabajos realizados son relativamente recientes. Es necesario, por consiguiente, ampliar la investigación sobre el tiempo libre, realizando más trabajos, desde un enfoque psicosocial, que profundicen en el tipo de ocio más beneficioso para los adolescentes y en cómo este ocio puede ser regulado administrativa y socialmente

The adolescence has aroused great interest among developmental psychologists and the proof is the numerous scientific publications that it can be found today on this period of life. In adolescent development, becomes very important leisure, socializing context transverse to the school, family and peers, an informal setting where learning of values and attitudes, skills and abilities, habits and ways of relating are also produced and where it contributes to the satisfaction of psychological needs. The self-determination theory is a descriptive model of human motivation, which can be applied to the study of the implications leisure activities in the healthy development and well-being of adolescents. In our country the scientific literature on the use of time of adolescents is scarce, and discussions are relatively recent. It is necessary, therefore, to expand research on leisure, doing more work, from a psychosocial approach, which contributes to the type most beneficial for teens leisure and how this can be regulated administrative and socially

Anthropometric, physiological and maturational characteristics in selected elite and non-elite male adolescent basketball players.

We investigated the anthropometric, physiological and maturation characteristics of young players (13-14 years old) associated with being successful in basketball. Body parameters were measured (stature, total body mass, skinfolds and lengths) and physiological capacities were assessed by endurance, sprint (20 m), jump and dribbling tests. Chronological age (CA) was recorded and maturity estimated using predicted age at peak height velocity (APHV). Anthropometric analysis indicated that elite players were taller, heavier and had a higher percentage of muscle. Further, physiological testing showed that these elite players perform better in jump, endurance, speed and agility tests (especially in the agility and ball tests). In addition, these skills are correlated with point average during the regular season. More basketball players born in the first semester of the year are selected and there is a predominance of early-maturing boys among those selected for the elite team. Those who are more mature have advantages in anthropometric characteristics and physiological test results. In conclusion, around puberty, physical and physiological parameters associated with maturity and CA are important in determining the success of basketball players. These findings should be taken into account by trainers and coaches, to avoid artificial bias in their selection choices.

Influence of nutrient intake on antioxidant capacity, muscle damage and white blood cell count in female soccer players.

BACKGROUND: Soccer is a form of exercise that induces inflammatory response, as well as an increase in free radicals potentially leading to muscle injury. Balanced nutritional intake provides important antioxidant vitamins, including vitamins A, C and E, which may assist in preventing exercise-related muscle damage. The purpose of the present study was to determine the effect of macro/micronutrient intake on markers of oxidative stress, muscle damage, inflammatory and immune response in female soccer players. METHODS: Twenty-eight female players belonging to two soccer teams of the same professional soccer club participated in this study after being informed about the aims and procedures and after delivering written consent. Each team completed an 8-day dietary record and played one competition match the same week. Participants were divided into two groups: the REC group (who complied with recommended intakes) and the NO-REC group (who were not compliant). Laboratory blood tests were carried out to determine hematological, electrolytic and hormonal variables, as well as to monitor markers of cell damage and oxidative stress. Blood samples were obtained 24 h before, immediately after and 18 h after official soccer matches. Student t-test or Mann-Whitney U-test was used to compare both groups throughout the match. RESULTS: At rest, we observed that the REC group had higher levels of total antioxidant status (TAS), glutathione peroxidase (GPx), and lower levels of creatine kinase (CK) and lactate dehydrogenase (LDH) in comparison to the NO-REC group. Immediately after the match, levels of TAS, GPx, superoxide dismutase (SOD), LDH and % lymphocytes were higher and the % of neutrophils were lower in the REC group compared to the NO-REC group. These differences were also maintained 18 h post-match, only for TAS and GPx. CONCLUSIONS: Our data reveal an association between nutritional intake and muscle damage, oxidative stress, immunity and inflammation markers. The benefit of the intake of specific nutrients may contribute to preventing the undesirable physiological effects provoked by soccer matches.

Metabolic impact of a soccer match on female players.

The aim of this study was to examine the metabolic effect of a female soccer match in elite and sub-elite teams. Blood samples were taken (24 h before, immediately after and 18 h after official soccer matches) to determine haematological, electrolytic and hormonal variables, as well as the levels of cell damage and oxidative stress in 14 elite and 14 sub-elite players. Our results show increases in white blood cell count (P < 0.001) and the percentage of neutrophils (P < 0.001), and decreases in the percentage of lymphocytes (P < 0.05), eosinophils (P < 0.001), monocytes (P < 0.001) and basophils (P < 0.05) immediately post-match. Increases were also found in lactate dehydrogenase activity (P < 0.001), uric acid (P < 0.001), albumin (P < 0.001), total antioxidant status (P < 0.001) and free testosterone levels (P < 0.01). Creatine kinase activity significantly increased 18 h post-match (P < 0.01) and the concentrations of several ions, glucose and proteins were found to be altered immediately post-match. Overall, our results show that playing a soccer match exerts specific metabolic effects on female players, resulting in muscle damage, oxidative stress and biochemical and hormonal variations. On the basis of some interesting correlations, we also suggest that exercise-induced cell breakdown may enhance antioxidant capacity of the soccer players.

Cell damage, antioxidant status, and cortisol levels related to nutrition in ski mountaineering during a two-day race.

The aim of this study was to measure the effect of nutrition on cell damage, antioxidant enzymes, and cortisol during a two-day ski mountaineering competition. Twenty-one male skiers participated in the study. Creatine kinase (CK), aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ-glutamyl transpeptidase (GGT), lactate dehydrogenase (LDH), alkaline phosphatase (AP), cortisol and C-reactive protein (CRP), glutathione peroxidase (GPx) and reductase activities (GR) and C-reactive protein (CRP) levels, total antioxidant status, and cortisol levels were measured in serum the day before and immediately after the race. Their diet was also analysed during the competition. Enzymes and cortisol levels significantly increased after the competition. CK and LDH and cortisol levels were negatively correlated to total energy, protein, and fat intake. Intake of vitamin A, B1, B2, B6 and niacin was negatively correlated to LDH and AP. A negative correlation was also found between CK activity and Na, Fe, and Zn intake. Cortisol levels were negatively correlated to the intake of vitamins C, B1 and B2, and niacin. A positive correlation was found between serum GPx and intake of energy, carbohydrates, proteins, A and B vitamins, and folic acid. Skiers with the lowest nutrient intake during the competition were the ones who showed greater cell damage and lower antioxidant enzyme activity and cortisol levels, which may impair performance and also cause injuries and accidents. Particularly, skiers should have high intakes of total energy, macronutrients, vitamins A and B, Na, Zn, and Fe in order to decrease the deleterious effect of strenuous exercise. Key pointsA two-day ski mountaineering race produced muscle cell damage and oxidative stress and an increase in cortisol levels.There was a marked insufficient intake of carbohydrates which has been shown to affect performanceThose skiers with lowest nutrient intake showed greater cell damage, lower antioxidant activity and higher cortisol levels.Nutrition should be carefully monitored and assessed in order to minimize the mentioned blood changes to avoid fatigue, injuries and also accidents in this type of sport; particularly when skiers must carry their own food.

Anthropometric and physiological differences between first team and reserve soccer players aged 10-14 years at the beginning and end of the season.

The aim of this article was to identify differences in the anthropometric and physiological characteristics of first team and reserve young soccer players (10-14 years old) at both the beginning and end of the soccer season. Body composition was calculated by measuring weight, height, skinfold, limb circumference, and joint diameter. Vo2max was estimated by Astrand's test. Sprint and jump tests were also performed. In general, first team players (FTPs) were taller and leaner. However, the most relevant difference that we found at the beginning of the season was that FTPs had shorter sprint times than reserves in the 30-m test (both flat and with 10 cones). Moreover, these differences in sprint time were more marked at the end of the season. In addition, jump test performance by the reserves declined from the beginning to the end of the season. These results indicate that sprint time is an important factor associated with selection as an FTP between the ages of 10 and 14 years. The progression of the FTPs during the course of the season is better than that of the reserves and is associated with a different degree of growth and maturity. These findings should be taken into account by trainers and coaches to avoid a bias against late maturing or younger soccer players.

Aneurismas sintomáticos de arterias viscerales. Tratamiento quirúrgico y endovascular: a propósito de dos casos / Symptomatic visceral artery aneurysms. Surgical and endovascular treatment: two case reports

Introducción. Los aneurismas de las arterias viscerales son entidades poco comunes con una incidencia estimada de 0,01-2%. Su importancia clínica se debe a que su historia natural se caracteriza por una tendencia a la rotura, con una tasa de mortalidad que puede llegar a ser de hasta un 70%. Con el desarrollo de las nuevas técnicas de imagen ha crecido el número de hallazgos casuales de esta patología. El tratamiento clásico de estos aneurismas ha consistido en la cirugía ‘a cielo abierto’, pero con el desarrollo de las técnicas endovasculares, se ha establecido una alternativa terapéutica con menores tasas de morbimortalidad. Casos clínicos. Presentamos un caso de aneurisma de arteria mesentérica superior, tratado mediante cirugía abierta, y otro caso de aneurisma de arteria hepática tratado mediante terapia endovascular, ambos sintomáticos y con buena evolución postoperatoria. Conclusiones. El tratamiento de los aneurismas de arterias viscerales tiene como finalidad evitar su rotura y las complicaciones derivadas. El riesgo de rotura viene determinado principalmente por su tamaño y localización. La terapia endovascular presenta como principal ventaja la menor invasividad del procedimiento; sin embargo, no existen estudios comparativos, por lo que no podemos hablar de la superioridad de una terapia respecto de la otra en el tratamiento de los aneurismas viscerales

Introduction. Aneurysms in the visceral arteries are uncommon conditions with an estimated incidence of 0.01-2%. Their clinical importance derives from the fact that their natural history is characterised by a tendency to rupture, with a mortality rate that can reach up to 70%. With the development of the latest imaging techniques the number of chance findings of this pathology has grown. Treatment of these aneurysms has traditionally consisted in open surgery, but the advances in endovascular techniques have made it possible to establish a therapeutic alternative with lower morbidity and mortality rates. Case reports. We report one case of superior mesenteric artery aneurysm, which was treated using open surgery, and another case of hepatic artery aneurysm that was treated by means of endovascular therapy; both of them were asymptomatic and post-operative progress was good in the two cases. Conclusions. The aim of treating aneurysms in visceral arteries is to prevent rupture and the ensuing complications. The risk of rupture is chiefly determined by their size and location. The main advantage of endovascular therapy is that the procedure is less invasive. Nevertheless, to date no comparative studies have been conducted and so we cannot talk of one therapy being better than the other in the treatment of visceral aneurysms

Síndrome del martillo hipotenar atípico / Atypical hypothenar hammer syndrome

Introducción. La isquemia aguda por embolización distal de un aneurisma cubital es infrecuente. La mayoría de los casos descritos en la bibliografía se relacionan con el síndrome del martillo hipotenar (SMH). Caso clínico. Varón de 45 años, con dolor, parestesias y frialdad de inicio súbito en el cuarto y el quinto dedos del miembro superior derecho. En la exploración física había pulsos presentes y simétricos en miembros superiores. Frialdad y subcianosis en el quinto dedo derecho y en menor grado en el cuarto, leve disminución de la sensibilidad y movilidad conservada. Sensación de masa no pulsátil en la región hipotenar derecha. El eco-Doppler mostró una curva de oclusión distal cubital y un aneurisma trombosado de arteria cubital de 0,4 × 0,8 cm en la región hipotenar. La fotopletismografía era plana en el cuarto y quinto dedos. La angiorresonancia mostraba un aneurisma de arteria cubital distal con ausencia del arco palmar profundo y la arteriografía una arteria cubital de fino calibre con retraso en su opacificación. Conclusiones. Por los hallazgos clinicorradiológicos, y al referir el paciente el traumatismo repetitivo en la eminencia hipotenar por el uso del ordenador personal, se estableció el diagnóstico de SMH atípico. La evolución clínica fue favorable con tratamiento médico (heparina de bajo peso molecular y analgesia), desapareciendo la sintomatología durante las primeras 24 horas

Introduction. Acute ischaemia due to distal embolisation of an ulnar aneurysm is infrequent. Most of the cases reported in the literature are related to hypothenar hammer syndrome (HHS). Case report. We report the case of a 45-year-old male who suffered the sudden onset of pain, paresthesias and coldness in the 4th and 5th fingers of the right hand. The physical examination showed that pulses were present and symmetrical in the upper limbs. There was also coldness and pallor in the fifth finger of the right hand and to a lesser extent in the fourth, slightly reduced sensitivity and preserved mobility. A non-pulsating mass could be felt in the right hypothenar region. Doppler ultrasound scan revealed a distal ulnar occlusion curve and a 0.4 × 0.8 cm thrombosed aneurysm in the hypothenar region of the ulnar artery. The photoplethysmography recording was flat in the fourth and fifth fingers. Magnetic resonance angiography showed a distal ulnar artery aneurysm with the absence of the deep palmar arch and the arteriography scan revealed the presence of a thin ulnar artery with delayed opaquing. Conclusions. The clinical-imaging findings and the patient’s reporting repeated traumatic injury to the hypothenar eminence from using a personal computer led us to establish a diagnosis of atypical HHS. Clinical progress was favourable with medical treatment (low-molecular-weight heparin and analgesics) and the symptoms disappeared within the first 24 hours

Physiological and anthropometric characteristics of young soccer players according to their playing position: relevance for the selection process.

The aim of this study was to establish the anthropometric and physiological profiles of young nonelite soccer players according to their playing position, and to determine their relevance for the selection process. Two hundred forty-one male soccer players who were members of the Getxo Arenas Club (Bizkaia) participated in this study. Players, age 17.31 (+/- 2.64) years, range 14-21 years, were classified into the following groups: forwards (n = 56), midfielders (n = 79), defenders (n = 77), and goalkeepers (n = 29). Anthropometric variables of participants (height, weight, body mass index, 6 skinfolds, 4 diameters, and 3 perimeters) were measured. Also, their somatotype and body composition (weights and percentages of fat, bone, and muscle) were calculated. Participants performed the Astrand test to estimate their absolute and relative VO2max, an endurance test, sprint tests (30 meters flat and 30 meters with 10 cones) and 3 jump tests (squat jump, counter movement jump and drop jump). Forwards were the leanest, presenting the highest percentage of muscle. They were the best performers in all the physiological tests, including endurance, velocity, agility, and power. In contrast, goalkeepers were found to be the tallest and the heaviest players. They also had the largest fat skinfolds and the highest fat percentage, but their aerobic capacity was the lowest. In the selection process, agility and the jump tests were the most discriminating for forwards. In contrast, agility, height, and endurance were the key factors for midfielders. The defenders group was characterized by a lower quantity of fat. Thus, we may conclude that anthropometric and physiological differences exist among soccer players who play in different positions. These differences fit with their different workload in a game. Therefore, training programs should include specific sessions for each positional role.

Ontogeny of prolyl endopeptidase and pyroglutamyl peptidase I in rat tissues.

Prolyl endopeptidase and pyroglutamyl peptidase I are enzymes which participate in the degradation of thyrotropin-releasing hormone (TRH), a hormone which is thought to play an important role in the development of organs and tissues. Here, we have characterized the ontogeny of TRH degrading enzyme activity in the brain cortex, lung, heart, kidney and liver. Overall, prolyl endopeptidase activity was found to be 2 to 5 fold higher in newborn vs. adult rat tissues, with the exception of the soluble form in the liver and the particulate form in the lung. In contrast, the developmental profile of pyroglutamyl peptidase I activity was found to be more variable and tissue dependent. These results corroborate the idea that both enzymes play important, tissue-specific roles during the development and maturation of rat organs.

Exercise, physical fitness, and dietary habits of first-year female nursing students.

The objective of the present study was to evaluate the practice of regular physical exercise, the anthropometrical and physiological characteristics, and the dietary habits of a group of female nursing students (n=46) and of a control group of female students from other disciplines (n=58) attending the University of the Basque Country. To this end, diets and leisure-time physical exercise were analyzed and the following variables were measured: body mass index, body composition, blood pressure, maximal oxygen consumption (VO2 max), and explosive muscle strength. Results show that the percentage of sedentary students was higher among first-year nursing students (50%) than among other matched students (43.6%). Regular physical exercise in nursing students was found to be positively correlated with higher absolute (p < .01) and relative VO2 max (p < 0.05) and with lower diastolic blood pressure (p < 0.05). Analysis of the diets of the nursing students showed that their energetic intake was deficient and was very low in carbohydrates and very high in fat and protein. Statistically significant differences between the two groups in anthropometric indices were not observed. The competence to provide adequate nutritional and preventive physical exercise recommendations was higher among active final-year nursing students than among sedentary final-year nursing students. Overall, the results of the present study highlight the need for a greater emphasis on the benefits of regular physical exercise and an adequate nutritional education early in the nursing educational program to encourage students to adopt healthier behaviors and to provide more effective preventive physical exercise and nutritional counseling for their future patients.

Nutritional intake in soccer players of different ages.

The purpose of this study was to evaluate the dietary practices of soccer players of different ages. The diets of the members of four soccer teams (mean ages of 14.0, 15.0, 16.6 and 20.9 years, respectively) were examined. Our results show that the caloric intake per kilogram of body mass was significantly higher among the youngest players when compared with the adult players (P < 0.05). The contribution of carbohydrates to total energy intake was lower than that recommended for athletes. This contribution decreased with age from 47.4% of total energy intake for the 14-year-olds to 44.6% for the adult players. No significant differences in protein or total fat intake were detected among the teams examined. Overall, our results show that the nutritional intake of the soccer players was not optimal, and that this intake was poorer among the adult players than among the adolescents. On the basis of our results, we recommended that nutritional education should be given to soccer players at an early age and should continue throughout adolescence, not only with a view to improving performance but also to promoting more healthy dietary practices in the long term.

Ontogeny of soluble and particulate prolyl endopeptidase activity in several areas of the rat brain and in the pituitary gland.

We have analyzed the activity of prolyl endopeptidase (PEP) in several areas of the rat brain (brain cortex, striatum, brain stem, cerebellum and hypothalamus) and in the pituitary gland during ontogeny. In all of these areas, we observed a reduction in PEP activity during development. However, the temporal profile of these alterations was found to be area specific and differences in the ontogeny of the soluble and particulate forms of PEP were observed. Thus, by postnatal day 20 (PD20), soluble PEP activity had began to decrease in the brain cortex and striatum, whereas decreased soluble PEP activity was observed earlier, at PD15, in the brain stem and cerebellum. Changes in the particulate fraction were even more pronounced. Senescence was associated with decreased soluble PEP activity in the striatum, but in contrast, particulate PEP activity was found to be increased in the senescent brain stem. The present results indicate that alterations in the levels of activity of PEP may represent an important event in the development and aging of the central nervous system.

Effect of aging on rat tissue peptidase activities.

The process of aging is known to involve alterations in the activity of peptidases and proteases. However, the precise changes in the activity of many peptidases in aged tissues have not yet been fully characterized, and both decreases and increases in both peptidase activity and peptide levels have been reported to occur during the aging process. In the present study, we measured the activity of several peptidases in selected tissues (brain cortex, brain stem, liver, kidney, heart, and lung) of the young adult (3 months old) and aged (18 months old and 22 months old) rat. The activities of prolyl endopeptidase, pyroglutamyl peptidase I, puromycin sensitive aminopeptidase, and aminopeptidase N were assayed using beta-naphthylamine aminoacidic derivatives as substrates. The activity of the soluble fractions of prolyl endopeptidase was found to be reduced in the lungs of aged animals, while reduced activity of soluble pyroglutamyl peptidase I and also aminopeptidase N was measured in the aged kidney and heart, respectively. In contrast, increased activity of particulate prolyl endopeptidase was measured in the brain stem of older animals. Since most of these changes can be correlated with known alterations in the levels of peptides controlled by each enzyme, the results of the present study indicate that the studied peptidases may play an important role in regulating tissue peptide levels during aging.