Diagnosis of urinary tract infection in infants under 3 months with fever without a source: reliability of urinalysis and urine culture.

BACKGROUND: Urinary tract infection (UTI) is infants' most common serious bacterial infection. This study aimed to investigate the reliability of urianalysis (UA) to predict UTI, to specify the colony forming units (CFU)/ml threshold for diagnosis, and to identify variables that help suspect bacteremia in infants under 3 months with UTI. METHODS: We reviewed clinical records of children under 3 months hospitalized for a fever without source and recorded age, sex, days of fever pre-consultation, temperature and severity at admission, discharge diagnoses, laboratory tests, and treatments. According to the discharge diagnosis, we divided them into UTIs (-) and (+) with or without bacteremia. RESULTS: A total of 467 infants were admitted: 334 with UTI and 133 without UTI. In UTIs (+), the pyuria had a sensitivity of 95.8% and bacteria (+) 88.3%; specificity was high, especially for nitrites (96.2%) and bacteria (+) (92.5%). Positive predictive value (PPV) for nitrites was 95.9%, for bacteria 96.7%, and oyuria 92.5%. Escherichia coli was present in 83.8% of urine and 87% of blood cultures. UTIs with bacteremia had inflammatory urinalysis, urine culture > 100,000 CFU/ml, and higher percentage of C reactive protein (CRP) > 50 mg (p= 0.002); 94.6% of the urine culture had > 50,000 CFU. CONCLUSIONS: The pyuria and bacteria (+) in urine obtained by catheterization predict UTI. The cut-off point for diagnosis was ≥ 50,000 CFU/ml. No variables to suspect bacteremia were identified in this study.

INTRODUCCIÓN: La infección del tracto urinario (ITU) es una infección bacteriana grave frecuente en lactantes. El objetivo de este trabajo fue investigar la fiabilidad del análisis de orina (AO) para predecirla, precisar el umbral de unidades formadoras de colonias (UFC)/ml para el diagnóstico y buscar variables que ayuden a sospechar de bacteriemia en lactantes menores de 3 meses con ITU. MÉTODOS: Se revisaron fichas clínicas de lactantes menores de 3 meses hospitalizados por fiebre sin foco evidente, registrando edad, sexo, días de fiebre preconsulta, temperatura y gravedad al ingreso, diagnósticos de egreso, exámenes de laboratorio y tratamientos. Según diagnóstico de egreso, se separaron en ITU (-) y (+), con o sin bacteriemia. RESULTADOS: Ingresaron 467 lactantes: 334 con ITU y 133 sin ITU. En ITU (+), la sensibilidad de la piuria fue de 95.8% y bacterias (+) 88.3%; la especificidad fue alta para nitritos (96.2%) y bacterias (+) (92.5%). El valor predictivo positivo (VPP) fue de 95.9% para nitritos, 96.7% para bacterias y 92.5% para piuria. Escherichia coli se encontró en el 83.8% de los urocultivos (UC) (+) y en el 87% de los hemocultivos (+). Las ITU con bacteriemia presentaron elementos inflamatorios, UC con ≥ 100,000 UFC/ml y mayor porcentaje de proteína C reactiva (PCR) > 50 mg/l (p= 0.002); el 94.6% de los UC (+) tuvo ≥ 50,000 UFC/ml. CONCLUSIONES: La piuria y bacterias (+) en el AO son excelentes para pronosticar ITU en orina obtenida con sonda vesical y el punto de corte para el diagnóstico debe ser ≥ 50,000 UFC/ml. No encontramos señales que ayudaran a sospechar ITU con bacteriemia.

Diagnosis of urinary tract infection in infants under 3 months with fever without a source: reliability of urinalysis and urine culture / Diagnóstico de infección del tracto urinario en lactantes menores de 3 meses con fiebre sin foco identificado: fiabilidad del análisis de orina y urocultivo

Abstract Background: Urinary tract infection (UTI) is infants´ most common serious bacterial infection. This study aimed to investigate the reliability of urianalysis (UA) to predict UTI, to specify the colony forming units (CFU)/ml threshold for diagnosis, and to identify variables that help suspect bacteremia in infants under 3 months with UTI. Methods: We reviewed clinical records of children under 3 months hospitalized for a fever without source and recorded age, sex, days of fever pre-consultation, temperature and severity at admission, discharge diagnoses, laboratory tests, and treatments. According to the discharge diagnosis, we divided them into UTIs (-) and (+) with or without bacteremia. Results: A total of 467 infants were admitted: 334 with UTI and 133 without UTI. In UTIs (+), the pyuria had a sensitivity of 95.8% and bacteria (+) 88.3%; specificity was high, especially for nitrites (96.2%) and bacteria (+) (92.5%). Positive predictive value (PPV) for nitrites was 95.9%, for bacteria 96.7%, and oyuria 92.5%. Escherichia coli was present in 83.8% of urine and 87% of blood cultures. UTIs with bacteremia had inflammatory urinalysis, urine culture > 100,000 CFU/ml, and higher percentage of C reactive protein (CRP) > 50 mg (p= 0.002); 94.6% of the urine culture had > 50,000 CFU. Conclusions: The pyuria and bacteria (+) in urine obtained by catheterization predict UTI. The cut-off point for diagnosis was ≥ 50,000 CFU/ml. No variables to suspect bacteremia were identified in this study.

Resumen Introducción: La infección del tracto urinario (ITU) es una infección bacteriana grave frecuente en lactantes. El objetivo de este trabajo fue investigar la fiabilidad del análisis de orina (AO) para predecirla, precisar el umbral de unidades formadoras de colonias (UFC)/ml para el diagnóstico y buscar variables que ayuden a sospechar de bacteriemia en lactantes menores de 3 meses con ITU. Métodos: Se revisaron fichas clínicas de lactantes menores de 3 meses hospitalizados por fiebre sin foco evidente, registrando edad, sexo, días de fiebre preconsulta, temperatura y gravedad al ingreso, diagnósticos de egreso, exámenes de laboratorio y tratamientos. Según diagnóstico de egreso, se separaron en ITU (-) y (+), con o sin bacteriemia. Resultados: Ingresaron 467 lactantes: 334 con ITU y 133 sin ITU. En ITU (+), la sensibilidad de la piuria fue de 95.8% y bacterias (+) 88.3%; la especificidad fue alta para nitritos (96.2%) y bacterias (+) (92.5%). El valor predictivo positivo (VPP) fue de 95.9% para nitritos, 96.7% para bacterias y 92.5% para piuria. Escherichia coli se encontró en el 83.8% de los urocultivos (UC) (+) y en el 87% de los hemocultivos (+). Las ITU con bacteriemia presentaron elementos inflamatorios, UC con ≥ 100,000 UFC/ml y mayor porcentaje de proteína C reactiva (PCR) > 50 mg/l (p= 0.002); el 94.6% de los UC (+) tuvo ≥ 50,000 UFC/ml. Conclusiones: La piuria y bacterias (+) en el AO son excelentes para pronosticar ITU en orina obtenida con sonda vesical y el punto de corte para el diagnóstico debe ser ≥ 50,000 UFC/ml. No encontramos señales que ayudaran a sospechar ITU con bacteriemia.

[Febrile syndrome in children younger than 29 days]. / Síndrome febril en niños menores de 29 días.

INTRODUCTION: Acute fever of unknown origin (FUO) in children under 29 days is a worrying situation because of the risk of serious bacterial infection (SBI). OBJECTIVE: to study the main clinical and laboratory characteristics of a group of hospitalized children under 29 days with diagnosis of FUO. PATIENTS AND METHOD: Retrospective study of children under 29 days hospitalized due to FUO. The clinical records of the patients were reviewed, recording age, sex, history of fever before consultation, temperature at admission, estimated severity at admission and discharge, discharge diagnoses, laboratory tests, and indicated treatments. Patients were classified according to the severity of the discharge diagnosis, as severe (S) and non-severe (NS). The inclusion criteria were term newborn, age less than 29 days, fe ver > 38°C registered at home or admission, and history of < 4 days. RESULTS: 468 children with FUO were admitted. Concordance between severity at admission and discharge was low (Kappa = 0.125; p = 0.0007). 26.1% of children were S and 73.9% NS. In the S group, urinary tract infection domínate (70.5%) and in the NS, FUO (67.6%). The cut-off levels for leukocytes/mm3, C-reactive protein, and neutrophils/mm3 showed negative predictive values to rule out severe bacterial infection. Conclu sions: Most of the newborns presented mild severity at admission, but 24% of them had SBI, thus hospitalization and close clinical observation are always necessary. Laboratory tests, such as CRP, white blood cell and neutrophils count are not good predictors of SBI. Early treatment with antibio tics for patients who meet the low-risk criteria is debatable.

3D Printing in Modern Cardiology.

BACKGROUND: 3D printing represents an emerging technology in the field of cardiovascular medicine. 3D printing can help to perform a better analysis of complex anatomies to optimize intervention planning. METHODS: A systematic review was performed to illustrate the 3D printing technology and to describe the workflow to obtain 3D printed models from patient-specific images. Examples from our laboratory of the benefit of 3D printing in planning interventions were also reported. RESULTS: 3D printing technique is reliable when applied to high-quality 3D image data (CTA, CMR, 3D echography), but it still needs the involvement of expert operators for image segmentation and mesh refinement. 3D printed models could be useful in interventional planning, although prospective studies with comprehensive and clinically meaningful endpoints are required to demonstrate the clinical utility. CONCLUSION: 3D printing can be used to improve anatomy understanding and surgical planning.

Aspectos ecológicos de los moluscos de importancia médico-veterinaria en Villa Clara, Cuba / Ecological aspects of mollusks of medical-veterinary importance in the province of Villa Clara, Cuba

Este trabajo tiene como objetivo determinar algunos aspectos ecológicos de los moluscos fluviales y terrestres de importancia médica-veterinaria en 13 municipios de la provincia de Villa Clara, Cuba durante el año 2013. Se realizaron muestreos mensuales en 477 criaderos de moluscos. Se registraron 21 especies de moluscos fluviales (n=14) y terrestres (n=7). Dos especies fueron clasificadas como endémicas, 15 como locales y cuatro como introducidas (especies exóticas). En relación a su frecuencia de ocurrencia, 14 especies fueron constantes (66,7%), cinco especies fueron comunes (23,8%) y dos fueron raras (9,5%). Las cuatro principales especies de moluscos fluviales fueron: Tarebia granifera, Pomacea poeyana, Physella acuta y Corbicula fluminea en los municipios de Santa Clara, Placetas, Encrucijada, Camajuaní y Cifuentes. Los moluscos terrestres más representativos fueron Praticolella griseola, Zachrysia auricoma y Galba cubensis, en los municipios de Santa Clara y Placetas. Se encontró correlación positiva entre la riqueza y la abundancia malacológica. Pomacea bridgesii y T. granifera se encontraron menos asociadas a las otras 20 especies de moluscos en base a los dendrogramas de similaridad. El aumento de la temperatura máxima y la humedad relativa disminuye la abundancia total de moluscos. En la provincia de Villa Clara existe una amplia variedad de especies de moluscos de importancia médico-veterinaria fluvial y terrestre que pueden constituir un riesgo epidemiológico para la provincia

Subclinical hypothyroidism and cognitive dysfunction in the elderly.

While overt hypothyroidism is associated with reversible dementia in the elderly, the relationship of subclinical hypothyroidism with cognition remains a controversial issue. Our aim was to investigate the correlation between subclinical hypothyroidism and cognition in the elderly, with particular reference to long term memory and selective attention. We selected 337 outpatients (177 men and 160 women), mean age 74.3 years, excluding the subjects with thyroid dysfunction and those treated with drugs influencing thyroid function. The score of Mini Mental State Examination (MMSE) was significantly lower in the group of patients with subclinical hypothyroidism than in euthyroid subjects (p<0.03). It was observed that patients with subclinical hypothyroidism had a probability about 2 times greater (RR = 2.028, p<0.05) of developing cognitive impairment. Prose Memory Test (PMT) score resulted significantly lower in subjects with subclinical hypothyroidism (p<0.04). Considering the Matrix Test (MT) score, the performance was slightly reduced in subclinical hypothyroidism (NS). Furthermore, TSH was negatively correlated with MMSE (p<0.04), PMT (p<0.05) and MT score (NS). No correlation was found between FT4 and FT3 and MMSE, PMT and MT score. In the elderly, subclinical hypothyroidism is associated with cognitive impairment, and its impact on specific aspects of cognition (long term memory and selective attention) is less evident.

Effect of home-based telecardiology on chronic heart failure: costs and outcomes.

Chronic heart failure (CHF) remains a common cause of disability. We have investigated the use of home-based telecardiology (HBT) in CHF patients. Four hundred and twenty-six patients were enrolled in the study: 230 in the HBT group and 196 in the usual-care group. HBT consisted of trans-telephonic follow-up and electrocardiogram (ECG) monitoring, followed by visits from the paramedical and medical team. A one-lead ECG recording was transmitted to a receiving station, where a nurse was available for reporting and interactive teleconsultation. The patient could call the centre when assistance was required (tele-assistance), while the team could call the patient for scheduled appointments (telemonitoring). The one-year clinical outcomes showed that there was a significant reduction in rehospitalizations in the HBT group compared with the usual-care group (24% versus 34%, respectively). There was an increase in quality of life in the HBT group (mean Minnesota Living Questionnaire scores 29 and 23.5, respectively). The total costs were lower in the HBT group (107,494 and 140,874, respectively). The results suggest that a telecardiology service can detect and prevent clinical instability, reduce rehospitalization and lower the cost of managing CHF patients.

Telecardiology: one-lead electrocardiogram monitoring and nurse triage in chronic heart failure.

We investigated a home-based intervention based on telecardiology in patients with chronic heart failure (CHF). Two hundred and thirty CHF patients, aged 59 years (SD 9), in stable condition and with optimized therapy were enrolled. The programme consisted of trans-telephonic follow-up and electrocardiogram (ECG) monitoring followed by visits from a paramedical and medical team. The patient could call the centre when required (tele-assistance), while the team could call the patient at prescheduled times (telemonitoring). During the first 12 months, there were 3767 calls (873 ad hoc and 2894 scheduled calls). There were 648 events, including 126 episodes of asymptomatic hypotension and 168 episodes which were not due to cardiological symptoms. No actions were taken by the nurse after 2417 calls (64%). A change in therapy was suggested after 418 calls, hospital admission in 62 patients, further investigations for 243 patients and a consultation with the general practitioner in 41 patients. A total of 2303 one-lead ECG recordings were received (10 per patient); 126 recordings (6%) were diagnosed as pathological in comparison with the baseline one. The one-lead ECG recording was used for titration of beta-blockers in 79 patients (mean dosage 38 mg vs 42 mg, P<0.01). Home telenursing could be an important application of telemedicine and single-lead ECG recording seems to offer additional benefit in comparison with telephone follow-up alone.

The structure of the bilaminar zone in the human temporomandibular joint: a light and scanning electron microscopy study in young and elderly subjects.

The bilaminar zone (BZ) in the human temporomandibular joint (TMJ) of toothed adults (GI) and toothless, elderly humans (GII) were analysed using light and scanning electron microscopy (SEM). In both groups the BZ consists of an upper and a lower stratum of connective tissue separated by a vascularized middle region. The superior stratum contains bundles of collagen fibres disposed in different directions. The fibres are fairly thick and transversely oriented immediately posterior to the TMJ disc. The initial part of the inferior stratum contains curved bundles of collagen fibres oriented anterio-posteriorly. From the middle to the posterior part of the inferior stratum, the fibres are right-aligned in GI and clearly sinuous in nature in GII. In both groups, the middle and posterior portions of the middle region are distinguished by the presence of vessels and vascular spaces. Loosely arranged connective and adipose tissues are also evident. The vascular spaces are wider in GII than in GI. The predominance of type I collagen fibres is clear in all regions of the BZ in both groups. The elastic fibres lie parallel to the collagen fibres in both groups and they are thicker and more abundant in GI, apparently decreasing in GII.

The structure of the bilaminar zone in the human temporomandibular joint: a light and scanning electron microscopy study in young and elderly subjects / Estrutura da zona bilaminar na articulação temporomandibular humana: um estudo leve e microscopia eletrônica de varredura e assuntos antigos

The bilaminar zone (BZ) in the human temporomandibular joint (TMJ) of toothed adults (GI) and toothless, elderly humans (GII) were analysed using light and scanning electron microscopy (SEM). In both groups the BZ consists of an upper and a lower stratum of connective tissue separated by a vascularized middle region. The superior stratum contains bundles of collagem fibres disposed in diferent directions. The fibres are fairly thick and transversely oriented immediately posterior to the TMJ disc. The initial part of the inferior stratum contains curved bundles of collagem fibres oriented anterio-posteriorly. From the middle to the posterior part of the inferior stratum, the fibres are right-aligned in GI and clearly sinuous in nature in GII. In both groups, the middle and posterior portions of the middle region are distinguished by the presence of vessels and vascular spaces. Loosely arranged conective and adipose tissues are also evident. The vascular spaces are wider in GII than in GI. The predominance of type I collagen fibres is clear in all regions of the BZ in both groups. The elastic fibres lie parallel to the collagen fibres in both groups and they are thicker and more abundant in GI, apparently decreasing in GII

The arrangement of the trabecular bone in the vestibular surface of the human fetus mandible. A scanning electron microscopy study.

The characteristics of trabecular bone in human fetuses at seven to nine months of intra-uterine life were studied in the vestibular surface of the mental and body portions of the mandible. In the mental portion, many circular trabeculae joined by "bridges" were observed in the alveolar region (AR). In the 8-month old fetus are trabeculae with tortuous disposition in the medium region (MR). Oblique trabeculae with superior and inferior dispositions defining a triangular area (future mental fossae) are verified in 9-month old fetuses. Trabeculae circularly disposed and vascular foramina are present close to the apex of this area. In the basilar region (BR) some trabeculae obliquely oriented are observed disposed near to the mandibular symphysis. The longitudinal bundles of collagen fibers assume an antero-posterior direction. At 9-month age the vascular foramina range from 6 to 20 microns and the osteocyte lacunae ranging from 1 to 4 microns diameter, are present in mandibles from all ages examined. In the body portion the presence of circular trabeculae joined by "bridges" is the main characteristic of the AR. In the MR most of the trabeculae are circular and the longitudinal trabeculae of this region assume an antero-posterior direction. The laminar, antero-posterior and juxtaposed trabeculae lying parallel to mandible base are a characteristic of the BR. The bundles of collagen fibers exhibit the same pattern of the trabeculae. The vascular foramina of the BR are smaller than that of the precedent regions. In the body portion of the mandible from all ages examined the osteocyte lacunae range from 1 to 4 microns in diameter.

Changes in oxidative stress and cellular redox potential during myocardial storage for transplantation: experimental studies.

BACKGROUND: Cardioplegic solutions assure only a sub-optimal myocardial protection during prolonged storage for transplantation. The ultimate cause of myocardial damage during storage is unknown, but oxygen free radicals might be involved. We evaluated the occurrence of oxidative stress and changes in cellular redox potential after different periods of hypothermic storage. METHODS: Langendorff-perfused rabbit hearts were subjected to a protocol mimicking each stage of a cardiac transplantation procedure: explantation, storage and reperfusion. Three periods of storage were considered: Group A = 5 hours, Group B = 15 hours, and Group C = 24 hours. Oxidative stress was determined in terms of myocardial content and release of reduced (GSH) and oxidized (GSSG) glutathione, and cellular redox potential as oxidized and reduced pyridine nucleotides ratio (NAD/NADH). Data on mechanical function, cellular integrity and myocardial energetic status were collected. RESULTS: At the end of reperfusion, despite the different timings of storage, recovery of left ventricular developed pressure (46.1+/-7.0, 54.7+/-6.7, and 45.7+/-7.4% of the baseline pre-ischaemic value), energy charge (0.81+/-0.02, 0.81+/-0.02, and 0.77+/-0.01) and NAD/NADH ratio (8.87+/-1.08, 9.39+/-1.72, and 10.26+/-1.98) were similar in all groups (A, B and C). On the contrary, the rise in left ventricular resting pressure (LVRP) and GSH/GSSG ratio were significantly different between Group C, and Groups A and B (p<0.0001, analyzed by Generalized Estimating Equations model for repeated measures, and p<0.05, respectively). CONCLUSIONS: The pathophysiology of myocardial damage during hypothermic storage cannot be considered as a normothermic ischaemic injury and parameters other than energetic metabolism, such as thiolic redox state, are more predictive of functional recovery upon reperfusion.

Hibernating myocardium: its pathophysiology and clinical role.

Myocardial hibernation, as first defined by Rahimtoola, is a state of chronic contractile dysfunction in patients with coronary artery disease which is fully reversible upon reperfusion. Clinical conditions consistent with the existence of myocardial hibernation include unstable and stable angina, myocardial infarction heart failure, and anomalous origin of coronary arteries. The mechanisms of hibernation are not known. Morphological alterations have been described in the hibernating area of patients, but these information are strongly affected by the diagnostic criteria utilized to screen patients. It has been postulated that hibernation is an adaptive phenomenon occurring during ischemia. In this context, downregulation of contraction is not regarded as a consequence of energetic deficit, but as a regulatory event aimed at reducing energy expenditure, thereby maintaining integrity and viability. Thus, hibernation might bear a relationship to the phenomenon of low-flow perfusion-contraction matching, or repetitive stunning or preconditioning. Clear-cut evidence for the mechanism of hibernation in the clinical setting seems likely to remain elusive, because of the nature of the studies needed to document it. Current experimental evidence supports the view that hibernation, stunning, preconditioning, or their coexistence can be responsible for regional myocardial contractile dysfunction which is reversible upon reperfusion. These are all adaptive and protective phenomena independent of their terminology and strict definitions and do not always apply to the extremely complex situation of myocardial ischemia in man.

Metabolic derangement in ischemic heart disease and its therapeutic control.

The term myocardial ischemia describes a condition that exists when fractional uptake of oxygen in the heart is not sufficient to maintain the rate of cellular oxidation. This leads to extremely complex situations that have been extensively studied in recent years. Experimental research has been directed toward establishing the precise sequence of biochemical events leading to myocyte necrosis, as such knowledge could lead to rational treatments designed to delay myocardial cell death. At the present time, there is no simple answer to the question of what determines cell death and the failure to recover cell function after reperfusion. Problems arise because: (1) ischemic damage is not homogeneous and many factors may combine to cause cell death; (2) severity of biochemical changes and development of necrosis are usually linked (both the processes being dependent on the duration of ischemia) and it is impossible to establish a causal relation; and (3) the inevitability of necrosis can only be assessed by reperfusion of the ischemic myocardium. Restoration of flow, however, might result in numerous other negative consequences, thus directly influencing the degree of recovery. From the clinical point of view, we have recently learned that there are several potential manifestations and outcomes associated with myocardial ischemia and reperfusion. Without a doubt, ventricular dysfunction (either systolic or diastolic) of the ischemic zone is the most reliable clinical sign of ischemia, since electrocardiographic changes and symptoms are often absent. The ischemia-induced ventricular dysfunction, at least initially, is reversible, as early reperfusion of the myocardium results in restoration of normal metabolism and contraction. In the ischemic zone, recovery of contraction may occur instantaneously or, more frequently, with a considerable delay, thus yielding the condition recently recognized as the "stunned" myocardium. On the other hand, when ischemia is severe and prolonged, cell death may occur. Reperfusion at this stage is associated with the release of intracellular enzymes, damage of cell membranes, influx of calcium, persistent reduction of contractility, and eventual necrosis of at least a portion of the tissue. This entity has been called "reperfusion damage" by those who believe that much of the injury is the consequence of events occurring at the moment of reperfusion rather than a result of changes occurring during the period of ischemia. The existence of reperfusion damage, however, has been questioned, and it has been argued that, with the exception of induction of arrhythmias, it is difficult to be certain that reperfusion causes further injury. The existence of such an entity has clinical relevance, as it would imply the possibility of improving recovery with specific interventions applied at the time of reperfusion. In 1985, Rahimtoola described another possible outcome of myocardial ischemia. He demonstrated that late reperfusion (after months or even years) of an ischemic area showing ventricular wall-motion abnormalities might restore normal metabolism and function. He was the first to introduce the term "hibernating myocardium," referring to ischemic myocardium wherein the myocytes remain viable but in which contraction is chronically depressed. In this article we review our data on metabolic changes occurring during ischemia followed by reperfusion, obtained either in the isolated and perfused rabbit hearts or in ischemic heart disease patients undergoing intracoronary thrombolysis or aortocoronary bypass grafting.

Different outcomes of the reperfused myocardium: insights into the comments of stunning and hibernation.

There are several potential outcomes of myocardial ischaemia. When ischaemia is severe and prolonged, irreversible damage occurs and there is no recovery of contractile function. Interventions aimed at reducing mechanical activity and oxygen demand either before ischaemia or during reperfusion have been shown to delay the onset of ischaemic damage and to improve recovery during reperfusion. When myocardial ischaemia is less severe but still prolonged, myocytes may remain viable but exhibit depressed contractile function. Under these conditions, reperfusion restores complete contractile performance. This type of ischaemia leading to a reversible, chronic left ventricular dysfunction has been termed 'hibernating myocardium'. It is important clinically recognize hibernation as reperfusion of hibernating myocardium by angioplasty or heart surgery restores contraction and this correlates with long term survival. A third possible outcome after a short period of myocardial ischaemia is a transient post-ischaemic ventricular dysfunction, a situation termed 'stunned myocardium'.

Effects of felodipine on the ischemic heart: insight into the mechanism of cytoprotection.

To assess whether the administration of felodipine protects the myocardium in a dose-dependent manner against ischemia and reperfusion, isolated rabbit hearts were infused with three different concentrations of felodipine: 10(-10), 10(-9), and 10(-8) M. Diastolic and developed pressures were monitored; coronary effluent was collected and assayed for CPK activity and for noradrenaline concentration; mitochondria were harvested and assayed for respiratory activity; and ATP production and calcium content and tissue concentration of ATP, creatine phosphate (CP), and calcium were determined. The occurrence of oxidative stress during ischemia and reperfusion was also monitored in terms of tissue content and release of reduced (GSH) and oxidized (GSSG) glutathione. Treatment with felodipine at 10(-10) and 10(-9) M had no effect on the hearts when perfused under aerobic conditions, whilst the higher dose reduced developed pressure from 57.7 +/- 2.6 to 30.0 +/- 2.6 mmHg (p < 0.01). On reperfusion treated hearts recovered better than the untreated hearts with respect to left ventricular performance, replenishment of ATP and CP stores, and mitochondrial function. Recovery of developed pressure was 100% at 10(-8) M, 55% at 10(-9) M, and 46% at 10(-10) M. The reperfusion-induced tissue and mitochondrial calcium overload, release of CPK and noradrenaline, and oxidative stress were also significantly reduced. The effects of felodipine were dose dependent. Felodipine inhibited the initial rate of ATP-driven calcium uptake but failed to affect the initial rate of mitochondrial calcium transport. It is concluded that felodipine infusion provides dose-dependent protection of the heart against ischemia and reperfusion. Because this protection also occurred at 10(-9) M and 10(-10) M in the absence of a negative inotropic effect during normoxia and of a coronary dilatory effect during ischaemia, it cannot be attributed to an energy-sparing effect or to improvement in oxygen delivery. From our data we can envisage two other major mechanisms-(1) membrane protection and (2) reduction in oxygen toxicity. The ATP-sparing effect occurring at 10(-8) M is likely to be responsible for the further protection.

Relation between energy metabolism, glycolysis, noradrenaline release and duration of ischemia.

We studied the effect of 12-36 min of global ischemia followed by 36 min of reperfusion in Langendorff perfused rabbit hearts (n = 26). Metabolism was determined in terms of peak and total release of purines (adenosine, inosine, hypoxanthine), lactate and noradrenaline during reperfusion; and myocardial content of nucleotides (ATP, ADP, AMP), glycogen and noradrenaline at the end of reperfusion. An inverse relationship (r = -0.79) existed between duration of ischemia and developed pressure post-ischemia. Early during reperfusion, after 12 min of ischemia, the purine concentration (peak release) increased 100x (p < 0.01), that of lactate and noradrenaline 10x (p < 0.05). Total purine release rose with progression of the ischemic period (30x after 36 min of ischemia; p < 0.01), concomitant with a reduction in nucleotide content. Lactate release was independent from the duration of ischemia, although glycogen had declined by 30% (p < 0.01) after 36 min of ischemia. The acid insoluble glycogen fraction, which presumably contains proglycogen, increased substantially during short-term ischemia. Peak noradrenaline increased 100x, and 200x, (p < 0.05) after 24 and 36 min of ischemia, respectively. Total noradrenaline release due to various periods of ischemia mirrored its peak release. Function recovery was inversely related to total purine and noradrenaline efflux (both r = -0.81); it correlated with tissue nucleotide content (r = 0.84). In conclusion, larger amounts of noradrenaline are released only after a substantial drop in myocardial ATP. During severe ischemia ATP consumption more than limited ATP production by anaerobic glycolysis, is a key factor affecting recovery on subsequent reperfusion. In contrast to lactate efflux, purine and noradrenaline release are useful markers of ischemic and reperfusion damage.

Right heart failure chronically stimulates heat shock protein 72 in heart and liver but not in other tissues.

OBJECTIVES: During cardiac failure several ontogenically developed adaptional mechanisms are activated. Among these, heat-shock proteins (HSP) are expressed in response to stress. The aim of the present study was to investigate the HSP72 protein expression in lungs, liver, cardiac and skeletal muscles during congestive heart failure (CHF). METHODS: CHF was induced in Sprague-Dawley rats by a single intraperitoneal injection of monocrotaline (50 mg/kg). Two groups of animals emerged: a CHF group (n = 10) with right ventricular hypertrophy, pleural and peritoneal effusions, and an Hypertrophy group (n = 12) with right ventricular hypertrophy without CHF. The data for each group were compared with those of control (saline infused) age-matched rats. Lungs, liver, right and left ventricles, soleus, extensor digitorum longus and tibialis anterior muscles were excised and analyzed for HSP72 concentration by Western blot analysis using a specific monoclonal antibody. Noradrenaline levels in the heart were also measured using HPLC. RESULTS: The CHF group showed: (1) reduced right (0.460 +/- 0.090 vs 0.830 +/- 0.070 nmol/ventricle, P < 0.01) and left (1.10 +/- 0.09 vs 2.10 +/- 0.130 nmol/ventricle, P < 0.001) ventricular content of noradrenaline compared to the control; (2) significant activation of HSP72 concentration in right and left ventricles (39.4 +/- 1.6 vs 5 +/- 0.9% and 13 +/- 1.2 vs 3.5 +/- 0.6%, P < 0.001 both) and in the liver (39.8 +/- 11 vs 6 +/- 2%, P < 0.001); (3) no modification in HSP72 concentration in lungs and all of the peripheral muscles considered. The Hypertrophy group showed: (1) unchanged total noradrenaline tissue content as compared to the control; and (2) unmodified HSP72 concentration in all tissues analyzed. CONCLUSIONS: The present study demonstrates that CHF, but not compensatory hypertrophy, is a specific stimulus for chronic HSP72 induction in the heart and liver. On the contrary, CHF does not affect HSP in lungs and peripheral muscles. HSP 72 induction represents an intracellular marker of stress reaction which can persist chronically.

Left ventricular dysfunction due to the new ischemic outcomes: stunning and hibernation.

Several potential manifestations and outcomes are associated with myocardial ischemia and reperfusion. When ischemia is severe and prolonged, irreversible damage occurs and there is no recovery of contractile function. When ischemia is less severe or shorter in duration, recovery of contraction may occur instantaneously or more commonly, after considerable delay, which is the condition recognized as "stunned myocardium." Stunning is defined as a transient left ventricular dysfunction that persists after reperfusion despite the absence of irreversible damage and restoration of normal or near-normal coronary flow. Oxidative stress and alteration of calcium homeostasis during reperfusion are the probable causes of stunning. Clinically, stunning may occur after acute infarction, successful thrombolysis, unstable angina, angioplasty, resolution of coronary spasm, open-heart surgery, or transplantation. It can be treated with interventions aimed at prevention or reversal. When ischemia is prolonged but less severe, myocytes may remain viable but exhibit depressed contraction. Under these conditions, reperfusion restores normal contractile performance. This type of ischemia, leading to a reversible, chronic left ventricular dysfunction, has been termed "hibernating myocardium." The intrinsic mechanisms of this condition are unknown. Clinically, it is very important to diagnose hibernation because reperfusion of the hibernating myocardium by angioplasty or heart surgery restores contraction, and this correlates with long-term survival. A number of methods are available to access the hibernating myocardium. These include cardiac imaging techniques that evaluate myocardial viability, such as positron emission tomography and thallium myocardial imaging, or methods that evaluate contractile reserve, such as low-dose dobutamine echocardiography. Interestingly, reperfusion of patients with end-stage ischemic cardiomyopathy and hibernating myocardium can be considered an alternative to transplantation.

Computer-assisted assessment of the variations of sperm kinetics after semen treatment with Pellet Swim-up (PSu), and with centrifugation on a discontinuous Percoll gradient at reduced volumes (mini-CDPG).

The semen of the male partners of 37 infertile couples was analyzed with the use of the HTM-S Motility Analyzer (HTM-S MA). For each sample it was thus possible to assess the Total Concentration (TC), the Motile Cell Population Concentration (MCPC), the Progressive Cell Population Concentration (PCPC), the Average Path Velocity (VAP), the Straight Line Velocity (VSL), the Curvilinear Velocity (VCL), the Straightness (STR), the Linearity (LIN), the Lateral Head Displacement (ALH) and the Head Size (HS). The same parameters were then measured on the same semen after treatment with the Pellet Swim-up (PSu) and following Centrifugation on reduced-volume Discontinuous Percoll gradient (mini-CDPG). There was a significant difference in the TC (51.63 M/ml +/- 43.99 in the untreated ejaculate, 11.48 M/ml +/- 9.66 after PSu, 7.94 M/ml +/- 7.3 after mini-CDPG; chi r2 = 50.392, p < 0.05), in the MCPC (20.95 M/ml +/- 26.29 in the untreated ejaculate, 3.79 M/ml +/- 4.26 after PSu, and 2.74 M/ml +/- 3.73 after mini-CDPG; chi r2 = 33.55, p < 0.05), and in the PCPC (7.8 M/ml +/- 12.87 in the untreated ejaculate, 1.81 M/ml +/- 2.36 after PSu, and 1.28 M/ml +/- 1.73 after min-CDPG; chi r2 = 6.38; p < 0.05). The overall comparison between the couples showed a significant difference in the MCPC after PSu and after mini-CDPG (z = -2.09, p < 0.05) whereas no significant difference was found in the comparison off the results of either the TC after PSu and after mini-CDPG (z = -1.9; NS), or of the PCPC after PSu and after mini-CDPG (z = -1.68; NS).(ABSTRACT TRUNCATED AT 250 WORDS)