Pulmonary aspiration in preschool children with cystic fibrosis.

Pulmonary aspiration of gastric refluxate (PAGR) has been demonstrated in association with pulmonary inflammation in school aged children with Cystic Fibrosis (CF). We sought to determine if similar findings were present in preschool children. Pepsin was measured in Broncho-alveolar lavage (BAL) fluid collected from clinically stable preschool children with CF and controls. Elevated pepsin levels were found in a subgroup of children with CF, but this was not found to be associated with pulmonary infection, pulmonary inflammation or respiratory or gastrointestinal symptoms.

Investigation of the mechanisms mediating MDMA "Ecstasy"-induced increases in cerebro-cortical perfusion determined by btASL MRI.

RATIONALE: Acute administration of the recreational drug of abuse 3,4-methylenedioxymethamphetamine (MDMA; Ecstasy) has previously been shown to increase cerebro-cortical perfusion as determined by bolus-tracking arterial spin labelling (btASL) MRI. OBJECTIVES: The purpose of the current study was to assess the mechanisms mediating these changes following systemic administration of MDMA to rats. METHODS: Pharmacological manipulation of serotonergic, dopaminergic and nitrergic transmission was carried out to determine the mechanism of action of MDMA-induced increases in cortical perfusion using btASL MRI. RESULTS: Fenfluramine (10 mg/kg), like MDMA (20 mg/kg), increased cortical perfusion. Increased cortical perfusion was not obtained with the 5-HT2 receptor agonist 2,5-dimethoxy-4-iodophenyl-aminopropane hydrochloride (DOI) (1 mg/kg). Depletion of central 5-HT following systemic administration of the tryptophan hydroxylase inhibitor para-chlorophenylalanine (pCPA) produced effects similar to those observed with MDMA. Pre-treatment with the 5-HT receptor antagonist metergoline (4 mg/kg) or with the 5-HT reuptake inhibitor citalopram (30 mg/kg), however, failed to produce any effect alone or influence the response to MDMA. Pre-treatment with the dopamine D1 receptor antagonist SCH 23390 (1 mg/kg) failed to influence the changes in cortical perfusion obtained with MDMA. Treatment with the neuronal nitric oxide (NO) synthase inhibitor 7-nitroindazole (7-NI) (25 mg/kg) provoked no change in cerebral perfusion alone yet attenuated the MDMA-related increase in cortical perfusion. CONCLUSIONS: Cortical 5-HT depletion is associated with increases in perfusion although this mechanism alone does not account for MDMA-related changes. A role for NO, a key regulator of cerebrovascular perfusion, is implicated in MDMA-induced increases in cortical perfusion.

Sustitución de prótesis de pene: 1990-1999 / Replacement of penile prosthesis: 1990-1999

OBJETIVO: Analizar la serie de pacientes sometidos entre los años 1990 y 1999 a sustitución de su prótesis de pene debido a la aparición de algún tipo de complicación. MATERIAL Y MÉTODOS: 85 pacientes fueron sometidos a implante, siendo utilizados 13 modelos diferentes de prótesis. En 15 de estos pacientes (17,64 por ciento) ésta tuvo que ser sustituida una vez o más. La edad media en el momento de la sustitución fue de 51,5 años. El acceso quirúrgico más frecuente fue el infrapúbico. RESULTADOS: Se realizaron en total 32 intervenciones de sustitución protésica. Las causas principales fueron: fallo mecánico (13 casos, 40,62 por ciento); infección (10 casos, 31,25 por ciento); y perforación de cuerpos cavernosos (cinco casos, 15,62 por ciento). No se observó incremento progresivo en la incidencia de complicaciones en relación con el número ordinal de la prótesis implantada. Mejores resultados globales: Mentor Mark II y AMS 700 Ultrex Plus. Actualmente sólo ocho (53,33 por ciento) de los 15 pacientes reimplantados hacen uso normal de su prótesis. CONCLUSIONES: Los pacientes sometidos a sustitución de su prótesis de pene son fuente potencial de complicaciones posteriores. Su conocimiento y correcto manejo es importante, de cara a una mejora progresiva en los resultados finales, (sobre todo si éstos -como en nuestro caso- no son aptos para el conformismo) (AU)

[Replacement of prosthesis of the penis]. / Sustitución de prótesis de pene: 1990-1999.

OBJECTIVE: To analyze the series of patients who underwent replacement of their penile prosthesis between years 1990 to 1999, due to any kind of complication. MATERIAL AND METHODS: 85 patients underwent implantation, 13 different prosthesis models being utilized. It was replaced (once or more) in 15 of these patients (17.64%). The mean age at the moment of the replacement was 51.5 years. The most frequent surgical approach was the infrapubic one. RESULTS: A total of 32 prosthesis-replacement interventions were carried out. The main causes were: mechanical failure (13 cases, 40.62%); infection (10 cases, 31.25%); and corpus cavernosum perforation (five cases, 15.62%). Progressive increase of complications incidence with regard to the ordinal number of the implanted prosthesis was not observed. Best overall results: Mentor Mark II and AMS 700 Ultrex Plus. At present day, only eight (53.33%) out of 15 reimplanted patients use their prosthesis with normality. CONCLUSIONS: Those patients who undergo replacement of their penile prosthesis are potential sources for later complications. Their knowledge and proper handling is important in order to a progressive improvement of the final results, (above all if--such as our case--these ones are not suitable for conformity).

[Treatment of erectile dysfunction using intracavernous pharmacotherapy]. / Tratamiento de la disfunción erectil mediante farmacoterapia intracavernosa.

Intracavernous injection of vasodilators has been the greatest diagnostic and therapeutical breakthrough in erectile dysfunction (E.D.). After 15 years experience, these vasodilators have demonstrated efficacy rates over 85%. This suggests that most cases of E.D. are the result of and inability of the smooth muscle to relax. This paper presents an overview of the diagnostic and therapeutic use of intracavernous vasodilating drugs. It includes an extensive review of the literature and our personal series with regard to efficacy, indications, contraindications and side-effects of these compounds. Alprostadil i.c. injection (PGE1) is an effective (> 70%) and safe treatment, and its use has been accompanied by an increased quality of life of patients, with very few side effects. Currently, PGE1 is a first choice drug in the treatment of impotence. When no response is seen, or pain develops after PGE1 administration, a number of vasoactive compounds associations can be used instead (phentolamine + PGE1, papaverine + phentolamine, and papaverine + phentolamine + PGE1). The phentolamine + VIP association has shown encouraging results. Prior to prescribe IC treatment with vasoactive drugs it is necessary to conduct a basic diagnostic study, and advise the patient. If treatment is finally accepted, the performance of adequate training and detailed medical follow-up is crucial.

[Physiology of penile erection]. / Fisiología de la erección del pene.

Penile smooth muscle tone (arterial and trabecular) regulates the hemodynamic phenomena of erection. Nitric oxide is perhaps the most important mediator of penile smooth muscle relaxation and, consequently, of erection. Detumescence of the erect penis following contraction of the smooth muscles is mediated by the adrenergic nerves, which release noradrenalin that acts on alpha 1 adrenergic receptors. Other substances such as endothelin and prostanoids appear to be implicated in maintaining penile relaxation.

Effects of dietary mineral supplementation on the performance and mineral retentions of broilers at high ambient temperatures.

1. The relationship between broiler performance and two dietary mineral balance equations was investigated at a high constant ambient temperature (30 degrees C) using a range of 11 salt supplements given to male broiler chicks from 21 to 42 d of age. 2. No relationship was found between broiler performance and either of the two balance equations. 3. Re-evaluating these equations using retained, rather than dietary, mineral concentrations did not improve the relationship although changes in mineral retentions associated with the supplements indicated that dietary concentrations were not a good indicator of the impact of the diet on the bird's acid-base homoeostasis. 4. Evidence was found that metabolisable anions supplemented in association with mineral cations may have a significant effect on broiler performance.

Muscle acidosis during static exercise is associated with calf vasoconstriction.

In this study we measured (n = 6) the phosphocreatine-to-inorganic phosphate ratio (PCr/Pi), Pi, and pH with 31P-nuclear magnetic resonance (31P-NMR) in the human forearm during static work at 30% of maximal voluntary contraction (MVC) for 2 min followed immediately by 3 min of circulatory arrest (forearm arterial occlusion). Static exercise, with its central volitional and skeletal muscle metabolic and mechanical afferent components, caused a rise in heart rate (HR, 32%), blood pressure (BP, 29%), and calf vascular resistance (calf R, 30%). During forearm occlusion after static exercise, HR returned to base line, the increase in BP was attenuated by 30%, and calf R remained elevated and unchanged. The percent change in calf R was correlated with forearm cellular pH (R = 0.56, P less than 0.001) but only weakly associated with PCr/Pi (R = 0.33, P less than 0.042). 30% MVC for 1 min followed by arterial occlusion (3 min) reduced PCr/Pi by 65% and pH by 0.16 U (P less than 0.05). Calf R was unchanged. Circulatory arrest alone (20 min) caused no change in either pH or calf R but large changes in PCr/Pi (50% reduction). We conclude that 1) there is an association between forearm cellular acidosis and calf vasconstriction during static forearm exercise and 2) large changes in PCr/Pi without concomitant changes in pH are not associated with changes in calf R.

31P nuclear magnetic resonance study of the effect of hypoxemia on neonatal status epilepticus.

Prolonged neonatal seizures are often accompanied or exacerbated by hypoxemia. To determine the effects of hypoxemia on neonatal status epilepticus, we determined cerebral blood flow and cerebral metabolic state in groups of neonatal dogs subjected to hypoxia, to seizures during normoxia, or to seizures during hypoxia. The compensatory increase in cerebral blood flow was greatest in animals subjected to seizures during normoxia and somewhat less pronounced in animals made hypoxic. However, blood flow failed to increase in forebrain structures when animals were subjected to the combination of seizures and hypoxia. Accordingly, levels of adenosine triphosphate in forebrain (measured both by in vitro enzymatic analysis and by in vivo phosphorus-31 nuclear magnetic resonance spectroscopy) were depleted to the greatest degree in animals who were seizing while hypoxic. In addition, brain glucose was significantly reduced only in the seizure-hypoxia group. Systemic factors such as hypoxemia may play a critical role in the disruption of cerebral energy balance during neonatal status epilepticus.

Rechargeable silver-modified mercuric oxide-zinc cell for cardiac pacemakers.

Tests were conducted on rechargeable mercury-zinc pacemaker batteries under simulated and actual biologic conditions, using a variety of discharge rates and charging schedules. In tests on 96 cells at a 6.4 milliampere (ma) discharge, recharging once every 15 months of simulated pacing at a 25 microampere (mua) drain, the earliest cell failure occurred after an equivalent of 50 years of pacing. The mean pacing equivalent for all 96 cells was more than 140 years. In 6.4 ma discharge tests on 24 cells, recharging once every 8 days of simulated pacing, only 1 cell in 24 failed after an equivalent of more than 500 years of pacing (actual time 2 years). In tests on 13 cells pacing at a 200 mua drain without recharging, the simulated mean duration of pacing before total discharge was 4.8 years. Seven other cells at a 200 mua drain with periodic recharging continue to function normally after more than 7 years of actual time, simulating 56 years of pacing at a 25 mua drain. Cardiac pacemakers using the rechargeable mercury-zinc cell have been implanted in animals for more than 2 1/2 years and in patients for more than 1 year with all units continuing to function satisfactorily. It has been demonstrated unequivocally that a rechargeable mercury-zinc pacemaker will function continuously for more than 4 years without recharging and that periodic recharging will extend pacing life far beyond that predicted for lithium and nuclear primary power sources.

Chronic testing of a pacemaker that needs recharging only once every four years.

Since 1967, three series of rechargeable single-cell silver-mercuric oxide-zinc pacemakers have been implanted in dogs with complete heart block. The five nonhermetic units in series 1 failed after less than or equal to 18 months, primarily due to prototype cell deficiencies, although one cell functioned for eight years. The six units in series II contained improved cells, but failed due to gradual transepoxy fluid absorption after less than or equal to 31 months. All rechargeable cells were salvaged and dried, and, seven years after their manufacture, they continue to power pacing circuits. Series III now totals 20 doubly hermetically sealed units, tested for up to three years (total more than 300 months or 26 years), with no pacemaker failures. Accelerated tests indicate a minimum life of more than 50 years. A clinical trial is in progress.