Autophagy induction in atrophic muscle cells requires ULK1 activation by TRIM32 through unanchored K63-linked polyubiquitin chains

Optimal autophagic activity is crucial to maintain muscle integrity, with either reduced or excessive levels leading to specific myopathies. LGMD2H is a muscle dystrophy caused by mutations in the ubiquitin ligase TRIM32, whose function in muscles remains not fully understood. Here, we show that TRIM32 is required for the induction of muscle autophagy in atrophic conditions using both in vitro and in vivo mouse models. Trim32 inhibition results in a defective autophagy response to muscle atrophy, associated with increased ROS and MuRF1 levels. The proautophagic function of TRIM32 relies on its ability to bind the autophagy proteins AMBRA1 and ULK1 and stimulate ULK1 activity via unanchored K63-linked polyubiquitin. LGMD2H-causative mutations impair TRIM32's ability to bind ULK1 and induce autophagy. Collectively, our study revealed a role for TRIM32 in the regulation of muscle autophagy in response to atrophic stimuli, uncovering a previously unidentified mechanism by which ubiquitin ligases activate autophagy regulators.

Critical Appraisal of Indices for the Assessment of Baroreflex Sensitivity

The sequence technique and the spectral estimation of the alpha coefficient are currently employed for the assessment of “spontaneous” baroreflex sensitivity (BRS). The comparison of performance and effectiveness of these techniques is obtained by the analysis of systolic blood pressure (SBP) and pulse interval (PI) tracings recorded in conscious cats before and after baroreceptor denervation. Results indicate that (1) the average BRS estimates obtained by the sequence technique and by the alpha coefficient at the respiratory frequency are similar, (2) the alpha coefficients computed at the respiratory frequency tend to be higher than alpha coefficients estimated at 0.1 Hz, and (3) in spite of what is traditionally claimed, the PI-SBP coherence does not seem to represent a reliable parameter to enhance the specificity of the spectral estimate, because coherence values often remain above the 0.5 threshold also after baroreceptor denervation.

Linear and Fractal Heart Rate Dynamics during Sleep at High Altitude

Objectives: To investigate the effects of hypoxia during sleep on linear and self-similar components of heart rate variability (HRV) in eight healthy subjects at high altitude on Mount Everest.

Methods: ECG was monitored by using an innovative textile-based device, the MagIC system. For each subject three night recordings were performed at sea level (SL), at 3500 m and 5400 m above SL. RR Interval (RRI) was derived on a beat-by-beat basis from the ECG and the VLF, LF and HF spectral components and the LF/HF ratio were estimated. Short-(α1) and long-term (α2) scale exponents as well as the recently proposed spectrum of self-similarity coefficients, α(n) were estimated by detrended fluctuation analysis (DFA).

Results: With respect to SL, all HRV parameters but one (α2) were significantly modified at 3500 m. However, at 5400 m they tended to return to the SL values and this was in contrast with the increase in the hypobaric hypoxia and in the number of central sleep apneas occurring at higher altitude. The only HRV index that displayed changes at 5400 m was the DFA α(n) spectrum, with α(n) values significantly lower than at SL for 20 < n < 50 and higher for 200 < n < 400, being n the box size..

Conclusions: While the biological interpretation of these results is still in progress, our data indicates that the cardiac response to high altitude hypoxia during sleep can hardly be fully explored by traditional HRV estimators only, and requires the additional support of more sophisticated indexes exploring also nonlinear and fractal features of cardiac variability.

ICF-based approach to evaluating functionality in cardiac rehabilitation patients after heart surgery

BACKGROUND

Heart surgery is a frequent reason for admission to in-patient cardiac rehabilitation programmes. ICF approach has never been used to evaluate cardiac patients after major heart surgery.

AIM

The aim was to evaluate and measure functionality in cardiac patients who have undergone heart surgery, using for the first time the ICF-based approach and to assess whether such approach can be feasible and useful in cardiac rehabilitation.

DESIGN

Observational study.

SETTING

In-patients cardiac Rehabilitation Unit in Milan.

POPULATION

Fifty consecutively admitted patients who had undergone heart surgery (34 males, 16 females; mean age 65.7±12.5 years).

METHODS

We prepared a ICF-core set short enough to be feasible and practical. Patients were individually interviewed by different healthcare professionals (randomly selected from a group of two physicians, two physiotherapists and two psychologists) at the beginning (T1) and end of cardiac rehabilitation (T2) RESULTS: The sum of the scores of each ICF body function, body structure, activity and participation code significantly decreased between T1 and T2 (P<0.001). The environmental code scores significantly decreased in the case of facilitators between T1 and T2 (P=0.0051), but not in the case of barriers. There were significant correlations between the ICF body function scores and Barthel's index (ρ=0.381; P=0.006), NYHA class (ρ=0.404; P=0.004) and plasma Cr-P levels (r=0.31; P=0.03), between the ICF body structure codes and the Conley scale (ρ=0.306; P=0.02), and between the activity/participation codes and SpO2 (ρ=0.319; P=0.04). There were no correlations between the ICF environmental codes and clinical parameters.

CONCLUSION

The ICF-based data provided functional information that was consistent with the patients' clinical course.

CLINICAL REHABILITATION IMPACT

The core set used allowed to quantify important body functions and activities, including some areas that are generally insufficiently considered by healthcare professionals during cardiac rehabilitation, and document their improvement.

[B-mode sonography visualizing microemboli flow in the main cerebral arteries]

In a patient with a mechanical prosthetic aortic valve admitted for transient amnesia, transcranial duplex Doppler and B-mode sonography visualized the transit of microemboli along the main cerebral arteries. Gaseous microemboli resulting from a cavitation phenomenon at valve closure were seen as high-intensity transient signals (HITS). To our knowledge, this is the first report of microemboli flow visualized in B-mode.

K-nearest-neighbor conditional entropy approach for the assessment of the short-term complexity of cardiovascular control

Complexity analysis of short-term cardiovascular control is traditionally performed using entropy-based approaches including corrective terms or strategies to cope with the loss of reliability of conditional distributions with pattern length. This study proposes a new approach aiming at the estimation of conditional entropy (CE) from short data segments (about 250 samples) based on the k-nearest-neighbor technique. The main advantages are: (i) the control of the loss of reliability of the conditional distributions with the pattern length without introducing a priori information; (ii) the assessment of complexity indexes without fixing the pattern length to an arbitrary low value. The approach, referred to as k-nearest-neighbor conditional entropy (KNNCE), was contrasted with corrected approximate entropy (CApEn), sample entropy (SampEn) and corrected CE (CCE), being the most frequently exploited approaches for entropy-based complexity analysis of short cardiovascular series. Complexity indexes were evaluated during the selective pharmacological blockade of the vagal and/or sympathetic branches of the autonomic nervous system. We found that KNNCE was more powerful than CCE in detecting the decrease of complexity of heart period variability imposed by double autonomic blockade. In addition, KNNCE provides indexes indistinguishable from those derived from CApEn and SampEn. Since this result was obtained without using strategies to correct the CE estimate and without fixing the embedding dimension to an arbitrary low value, KNNCE is potentially more valuable than CCE, CApEn and SampEn when the number of past samples most useful to reduce the uncertainty of future behaviors is high and/or variable among conditions and/or groups.

Short-term complexity indexes of heart period and systolic arterial pressure variabilities provide complementary information

It is unclear whether the complexity of the variability of the systolic arterial pressure (SAP) provides complementary information to that of the heart period (HP). The complexity of HP and SAP variabilities was assessed from short beat-to-beat recordings (i.e., 256 cardiac beats). The evaluation was made during a pharmacological protocol that induced vagal blockade with atropine or a sympathetic blockade (beta-adrenergic blockade with propranolol or central sympathetic blockade with clonidine) alone or in combination, during a graded head-up tilt, and in patients with Parkinson's disease (PD) without orthostatic hypotension undergoing orthostatic challenge. Complexity was quantified according to the mean square prediction error (MSPE) derived from univariate autoregressive (AR) and multivariate AR (MAR) models. We found that: 1) MSPEMAR did not provide additional information to that of MSPEAR; 2) SAP variability was less complex than that of HP; 3) because HP complexity was reduced by either vagal blockade or vagal withdrawal induced by head-up tilt and was unaffected by beta-adrenergic blockade, HP was under vagal control; 4) because SAP complexity was increased by central sympathetic blockade and was unmodified by either vagal blockade or vagal withdrawal induced by head-up tilt, SAP was under sympathetic control; 5) SAP complexity was increased in patients with PD; and 6) during orthostatic challenge, the complexity of both HP and SAP variabilities in patients with PD remained high, thus indicating both vagal and sympathetic impairments. Complexity indexes derived from short HP and SAP beat-to-beat series provide complementary information and are helpful in detecting early autonomic dysfunction in patients with PD well before circulatory symptoms become noticeable.

24h seismocardiogram monitoring in ambulant subjects

Sternal seismocardiogram (SCG) is the assessment of microvibrations produced by the beating heart as detected by an accelerometer positioned on the sternum. This signal reflects mechanical events of the heart contraction, including the opening and closure of mitral and aortic valves and maximal blood flow acceleration. Traditionally, SCG has been detected in a laboratory setting with the subject lying at rest in supine position. Aims of this study were 1) to investigate the feasibility of a SCG monitoring over the 24 hours in ambulant subjects, and 2) to calculate number and time distribution of the SCG estimates obtainable over the 24 hours. In 5 healthy subjects ECG, respiration, body accelerations and sternal SCG were recorded for 24 hours in a workday by a smart garment recently developed in our laboratory, the MagIC-SCG system. Each recording was split into a series of contiguous 5-s data segments and SCG was estimated in each segment where the magnitude of the acceleration vector was < 4 milli-g (this condition indicates that the subject was not moving).All the 24-h recordings were found of good quality and could be entirely analyzed. A large number of SCG estimates could be obtained over the 24 hours. In particular, more than 100 estimates per hour were available during the day; at night this rate was three times higher.Thus our study indicates that not only the 24h SCG monitoring in daily life is feasible but also that possible changes over time in SCG and its derived parameters may be tracked with an extreme temporal detail.

The sequence technique revised: additional concepts on the assessment of spontaneous baroreflex function

The sequence technique is commonly employed to estimate the baroreflex sensitivity from the analysis of systolic blood pressure (SBP) and RR Interval (RRI) recordings. Traditionally, the RRI+/SBP- and RRI-/SBP+ sequences are excluded from this analysis.

Baroreflex contribution to blood pressure and heart rate oscillations: time scales, time-variant characteristics and nonlinearities

The aim of this paper is to highlight the aspects of the baroreflex control of the cardiovascular system that could be relevant to the analysis and modelling of cardiovascular oscillations and regulation. In particular, complex and/or controversial issues of the baroreflex control are addressed on the basis of results obtained in previous studies by others as well as by our group. Attention has been focused on time-variant and nonlinear characteristics of the baroreflex function and on the influence of this physiological mechanism on different frequency regions of blood pressure and heart rate spectra.

Dynamic adaptation of cardiac baroreflex sensitivity to prolonged exposure to microgravity: data from a 16-day spaceflight

This study explored the process of arterial baroreflex adaptation to microgravity, starting from the first day of flight, during the 16-day STS-107 Columbia Space Shuttle mission. Continuous blood pressure (BP), ECG, and respiratory frequency were collected in four astronauts on ground (baseline) and during flight at days 0–1, 6–7, and 12–13, both at rest and during moderate exercise (75 W) on a cycle ergometer. Sensitivity of the baroreflex heart rate control (BRS) was assessed by sequence and spectral alpha methods. Baroreflex effectiveness index (BEI); low-frequency (LF) power and high-frequency (HF) power of systolic BP (SBP), diastolic BP (DBP), and R-R interval (RRI); the RRI LF/HF ratio; and the RRI root mean square of successive differences (RMSSD) index were also estimated. We found that, at rest, BRS increased in early flight phase, compared with baseline (means ± SE: 18.3 ± 3.4 vs. 10.4 ± 1.2 ms/mmHg; P < 0.05), and it tended to return to baseline in subsequent days. During exercise, BRS was lower than at rest, without differences between preflight and in-flight values. At rest, in the early flight phase, RMSSD and RRI HF power increased ( P < 0.05) compared with baseline, whereas LF powers of SBP and DBP decreased. No statistical difference was found in these parameters during exercise before vs. during flight. These findings demonstrate that heart rate baroreflex sensitivity and markers of cardiac vagal modulation are enhanced during early exposure to microgravity, likely because of the blood centralization, and return to baseline values in subsequent flight phases, possibly because of the fluid loss. No deconditioning seems to occur in the baroreflex control of the heart.

Upgraded diagnostic value of Gen-Probe PACE 2 assay for detection of Chlamydia trachomatis infection

In this study, we evaluate the performance of a nucleic acid amplification assay, COBAS AMPLICOR (Roche Molecular systems) (PCR), compared to non-amplified DNA probe assay PACE2 (Gen-Probe Inc.) for the detection of C. trachomatis in a total of 2,916 samples (2,114 females and 802 males) consecutively collected in two different clinical pathology laboratories, over a period of three years. In the females, the endocervical swabs showed a similar range of detection when using the two different methods: out of 1,581 females processed with PACE 2, 1.4% (2005), 0.9% (2006), 0.5% (2007), resulted positive for C. trachomatis; out of 533 females processed with PCR, 1.3% (2005), 1.5% (2006) and 1.2% (2007), resulted positive. However, in the male subjects we found an increased positivity of Chlamydia detection on urethral swabs by using PACE 2: 4.8% (2005), 1.9% (2006) and 2.9% (2007), compared to urine specimen processed by PCR: 1% (2005), 1.4% (2006) and 0% (2007). Even if PCR should be considered a most promising tool for routine diagnosis of Chlamydia infection, Gen Probe allowed us to better identify Chlamydia trachomatis (in 4.8% of urethral swabs compared to urine) leading to a hypothesis that extracellular EB forms of Chlamydia could be absent in urine in persistent infectious.

Autonomic cardiovascular regulation in quiescent ulcerative colitis and Crohn's disease

BACKGROUND

In inflammatory bowel diseases, changes in autonomic enteric regulation may also affect neural cardiovascular control. However, while cardiac autonomic modulation has been shown to be impaired in active ulcerative colitis, the occurrence of cardiovascular autonomic alterations, also in the quiescent phase of inflammatory bowel diseases, is still a matter of debate. The aim of our study was thus to explore the features of cardiovascular autonomic regulation in ulcerative colitis and Crohn's disease during their remission phase.

MATERIALS AND METHODS

Autonomic cardiovascular control was evaluated by time- and frequency-domain indexes of spontaneous heart rate and blood pressure variability and by assessing the baroreflex heart rate control (sequence technique) in 26 patients with ulcerative colitis, in 26 patients with Crohn's disease and in 23 healthy controls.

RESULTS

The groups were matched for age, gender and body mass index. They had similar blood pressure mean levels and variability. By contrast, mean heart rate, its overall variability (standard deviation), and baroreflex sensitivity were lower in ulcerative colitis patients than in controls. Moreover, all indexes related to cardiac vagal control were significantly lower in ulcerative colitis patients with respect not only to controls but also to Crohn's disease patients.

CONCLUSIONS

Cardiac vagal control is impaired in quiescent ulcerative colitis only, and not in Crohn's disease, while in both bowel diseases vascular control appears preserved. Since cardiovagal modulation seems related to anti-inflammatory mechanisms, the reduced parasympathetic cardiac regulation in apparently quiescent ulcerative colitis suggests that such systemic derangement is accompanied by local subclinical inflammations, even in the absence of clinically active inflammatory processes.

Heart rate monitoring and control in altered gravity conditions

On the basis of indirect evidences it has been hypothesized that during space missions the almost complete absence of gravity might impair the baroreflex control of circulation. In the first part of this paper we report results obtained from a series of experiments carried out to directly verify this hypothesis during the 16-day STS 107 Shuttle flight. Spontaneous baroreflex sensitivity was assessed in four astronauts before flight (baseline) and at days 0-1, 6-7 and 12-13 during flight, both at rest and while performing moderate exercise. Our results indicate that at rest the baroreflex sensitivity significantly increased in the early flight phase, as compared to pre-flight values and tended to return to baseline in the mid-late phase of flight. During exercise, baroreflex sensitivity was lower than at rest, without any difference among pre-flight and in-flight values. These findings seem to exclude the hypothesis of an impairment of the baroreflex control of heart rate during exposure to microgravity, at least over a time window of 16 days. In the second part of the paper we propose a novel textile-based methodology for heart rate and other vital signs monitoring during gravity stress. The positive results obtained from its use during parachute jumps support the use of smart garments for the unobtrusive assessment of physiological parameters in extreme environments.

Baroreflex control of heart rate during sleep in severe obstructive sleep apnoea: effects of acute CPAP

Baroreflex control of heart rate during sleep (baroreflex sensitivity; BRS) has been shown to be depressed in obstructive sleep apnoea (OSA), and improved after treatment with continuous positive airway pressure (CPAP). Whether CPAP also acutely affects BRS during sleep in uncomplicated severe OSA is still debatable. Blood pressure was monitored during nocturnal polysomnography in 18 patients at baseline and during first-time CPAP application. Spontaneous BRS was analysed by the sequence method, and estimated as the mean sequence slope. CPAP did not acutely affect mean blood pressure or heart rate but decreased cardiovascular variability during sleep. Mean BRS increased slightly during CPAP application (from 6.5+/-2.4 to 7.5+/-2.9 ms x mmHg(-1)), mostly in response to decreasing blood pressure. The change in BRS did not correlate with changes in arterial oxygen saturation or apnoea/hypopnoea index. The small change in baroreflex control of heart rate during sleep at first application of continuous positive airway pressure in severe obstructive sleep apnoea was unrelated to the acute resolution of nocturnal hypoxaemia, and might reflect autonomic adjustments to positive intrathoracic pressure, and/or improved sleep architecture. The small increase in baroreflex control of heart rate during sleep may be of clinical relevance as it was accompanied by reduced cardiovascular variability, which is acknowledged as an independent cardiovascular risk factor.

Multi-and monofractal indices of short-term heart rate variability

Indices of heart rate variability (HRV) based on fractal signal models have recently been shown to possess value as predictors of mortality in specific patient populations. To develop more powerful clinical indices of HRV based on a fractal signal model, the study investigated two HRV indices based on a monofractal signal model called fractional Brownian motion and an index based on a multifractal signal model called multifractional Brownian motion. The performance of the indices was compared with an HRV index in common clinical use. To compare the indices, 18 normal subjects were subjected to postural changes, and the indices were compared on their ability to respond to the resulting autonomic events in HRV recordings. The magnitude of the response to postural change (normalised by the measurement variability) was assessed by analysis of variance and multiple comparison testing. Four HRV indices were investigated for this study: the standard deviation of all normal R-R intervals; an HRV index commonly used in the clinic; detrended fluctuation analysis, an HRV index found to be the most powerful predictor of mortality in a study of patients with depressed left ventricular function; an HRV index developed using the maximum likelihood estimation (MLE) technique for a monofractal signal model; and an HRV index developed for the analysis of multifractional Brownian motion signals. The HRV index based on the MLE technique was found to respond most strongly to the induced postural changes (95% CI). The magnitude of its response (normalised by the measurement variability) was at least 25% greater than any of the other indices tested.

Surgical conservative treatment for Bauhin's syndrome

BACKGROUND AND STUDY AIMS

Hypertrophy of ileocaecal sphincter seems to be the basic etiological factor of Bauhin's valve syndrome (BVS). In the rare literature all cases are treated by means of an hemicolectomy. A patient with Bauhin's valve syndrome is described, whose pathologic characteristics were hypertrophy of ileocaecal sphincter and a circular submucosal lipoma on the caecal side of the valve. Lipomata, although uncommon, may arise throughout the whole gastrointestinal tract, mostly asymptomatic, and submucosal layer is most frequently involved than subserosal one. More than two-thirds of gut lipoma are found in the large bowel, where they represent the most common benign lesion after adenoma.

PATIENTS AND METHODS

A 36 year old woman suffering from periodic upper abdominal pain, nausea and diarrhea, was submitted to an explorative surgical procedure, after imaging study of the bowel showed only an indistict mass in the caecum. Though a caecotomy a dissection of an hypertrophic and swollen portion of the ileocaecal valve was performed, saving the ileo-caecal sphincter. The residual mucosal margins were sutured, the last tract of the ileum was fixed to the caecum, completing with a caecorrhaphy and appendectomy.

RESULTS

Normal post-operative period, discharging the patient after few days. Since the operation all symptoms disappeared, and after four years there is a total well-being of the patient with complete disappearance of the former symptoms.

CONCLUSIONS

If the BVS is only due to a lipomatous hypertrophy of the mucosa and submucosa of ileo-caecal valve, hemicholectomy seems to be not justified: it is an exceedingly invasive procedure for a non-malignant disease. It is important a throughout radiological diagnosis and a caecotomy direct control during an operative exploration for a correct surgical choice.

Endocannabinoids, hormone-cytokine networks and human fertility

Anandamide (N -arachidonoylethanolamine, AEA) is a major endocannabinoid, shown to impair mouse pregnancy and embryo development and to induce apoptosis in blastocysts. Here, we review the roles of AEA, of the AEA-binding cannabinoid (CB) receptors, of the selective AEA membrane transporter (AMT), and of the AEA-hydrolyzing enzyme fatty acid amide hydrolase (FAAH), in human gestation. In particular, we discuss the interplay between the endocannabinoid system and the hormone-cytokine array involved in the control of human pregnancy, showing that the endocannabinoids take part in the immunological adaptation occurring during early pregnancy. In this line, we discuss the critical role of FAAH in human peripheral lymphocytes, showing that the expression of this enzyme is regulated by progesterone, Th1 and Th2 cytokines, which also regulate fertility. Moreover, we show that AEA and the other endocannabinoid, 2-arachidonoylglycerol, inhibit the release of the fertility-promoting cytokine leukemia inhibitory factor from human lymphocytes. Taken together, low FAAH and consistently high blood levels of AEA, but not CB receptors or AMT, can be early (<8 weeks of gestation) markers of spontaneous abortion, potentially useful as diagnostic tools for large-scale, routine monitoring of gestation in humans.

[Contribution to the knowledge on natural history of giant hepatic angioma]

Hepatic haemangiomas are mostly discovered by chance because of their limited dimensions. Their treatment is optional and very often an observing conservative strategy is adopted whilst a danger is foreseeing from different facts. Very different is the case of giant haemangiomas discovered because their bulk and discomfort coming from the compression exerted on near structures. In this cases a surgical treatment, segmentectomy or hemiepatectomy, are the current demanding choices. But if the volume of haemangioma is too bulky and occupies most hepatic parenchyma the necessary resection may be too extended and possibly dangerous. The two observations of the paper refer to two patients followed conservatively for over 20 years. In fact the volume of the haemangiomas in both patients was too large, the symptoms were only related to the weight of the mass and therefore a surgical solution was deferred to a possible worsening of the symptomatology. Such worsening didn't happen in the time for both the patients, demonstrating that the natural history of such lesion can also be very benign over many years.

Blood pressure and heart rate variability and baroreflex sensitivity before and after brain death

OBJECTIVES

To evaluate spontaneous blood pressure and heart rate variability and spontaneous baroreflex sensitivity before and after brain death.

METHODS

Spontaneous variability of arterial blood pressure and heart rate-estimated by power spectra of systolic (SBP) and diastolic blood pressure (DBP) and pulse interval (PI)-and spontaneous baroreflex sensitivity (BRS)-estimated by the alpha index and the sequence technique-were evaluated in 11 patients twice: shortly before and 1 hour after the onset of brain death.

RESULTS

Significant spectral changes occurred after brain death: a general power reduction in PI spectra; a shift of SBP, DBP and PI powers toward the lower frequencies, resulting in a greater slope of the "1/f" spectral trends; and a marked reduction of SBP and DBP powers (-93%) and of SBP-PI coherence (-63%) at 0.1 Hz. The estimated average BRS was relatively high before brain death (around 11 ms/mm Hg), and fell close to 0 or even was not detectable at all after brain death.

CONCLUSIONS

Parameters describing spontaneous blood pressure and heart rate variability and indexes reflecting the baroreflex function, which were relatively normal up to a few hours before brain death, underwent marked changes with the onset of brain death. All the changes found are likely to reflect the cessation of activity of the cardiovascular brain stem centres. These findings indicate that techniques of blood pressure and heart rate spectral analysis and of dynamic assessment of baroreflex sensitivity may be useful to complement the diagnosis of brain stem death.

Oxidation products of polyamines induce mitochondrial uncoupling and cytochrome c release

Spermine is shown to uncouple isolated mitochondria and to trigger the selective release of cytochrome c. Pargyline, an inhibitor of amine oxidase (AO), fully prevented these effects of spermine, which instead were potentiated by exogenous AO. Hydrogen peroxide, an oxidation product of spermine, mimicked the effects of spermine on mitochondria, while the addition of catalase prevented them. Spermidine and putrescine also caused mitochondrial uncoupling and triggered cytochrome c release, with a potency which correlated with the substrate preference of mitochondrial AO. Pargyline protected human lymphoma U937 cells against UVB-induced apoptosis, by reducing AO activity, mitochondrial uncoupling and cytochrome c release.

Dynamic modulation of baroreflex sensitivity in health and disease

Assessment of arterial baroreflex function in humans through laboratory tests has provided a great deal of information of pathophysiological and clinical relevance. Indeed, the sensitivity of the baroreceptor-heart rate reflex quantified through these laboratory methods was shown to predict the risk of cardiovascular events and death from myocardial infarction, heart failure, and in diabetic patients. This traditional approach, however, does not provide information on daily life baroreflex cardiovascular control. Modern techniques, based on computer analysis of spontaneous blood pressure and heart rate fluctuations, are now available and allow baroreflex sensitivity to be assessed under real-life conditions with no need for external stimulation. In particular, these methods offer the possibility of investigating the dynamic modulation of baroreflex sensitivity occurring either on a minute-to-minute basis or over 24 hours.

Potassium depletion and salt sensitivity in essential hypertension

To evaluate the actual role of potassium depletion on blood pressure, 11 hypertensive patients were placed on a 10-day isocaloric diet providing a daily potassium intake of either 18 or 80 mmol, with each subject serving as his or her own control; the intake of sodium (220 mmol/day) and other minerals was kept constant. On day 11 each patient was also subjected to central volume expansion by water immersion associated with either normal or low potassium intake. After a 10-day period of low potassium intake, systolic blood pressure increased (P < 0.02) by 5 mm Hg, whereas serum potassium decreased (P < 0.001) by 0.9 mmol/L; no significant changes in urinary sodium and a marked increase in urinary calcium excretion (P < 0.001) were found during the 10-day low potassium intake. PRA (P < 0.02) and plasma aldosterone (P < 0.04) concentrations also decreased during low potassium intake in hypertensive patients. Even though an identical natriuretic response was found during the water immersion experiments with either high or low potassium in the whole hypertensive group, the evaluation of hypertensive subjects in relation to salt sensitivity enabled us to disclose pronounced differences in the natriuretic and calciuretic response. In fact, although an impaired natriuretic ability and moderate calcium loss were particularly found during water immersion in those hypertensive subjects exhibiting a lower salt sensitivity index, a predominant calcium depletion appeared to be the most important consequence of potassium depletion in the hypertensive subjects with a higher salt sensitivity index. By confirming that potassium depletion may exacerbate essential hypertension, our data also suggest that not only sodium restriction, but also potassium and calcium supplementation, could be particularly advisable in salt-sensitive hypertensive patients.

[Blood pressure variability]

This review deals with a number of issues related to blood pressure variability. These include: historical aspects, with reference to the first pioneering observations; methodological aspects, focusing on the different methods for quantifying blood pressure variability; description of the characteristics of blood pressure variability over the 24 hours; mechanisms involved in determining the different magnitude of this phenomenon in different subjects, such as behavioral factors, central and reflex neural influences, humoral and mechanical factors; blood pressure variability as a probe to assess spontaneous baroreflex sensitivity; effects of aging and hypertension on blood pressure variability, with a discussion of the clinical relevance of this phenomenon in the prognostic evaluation of patients; effects of drugs on blood pressure variability. Finally methodological aspects related to the use of noninvasive ambulatory blood pressure monitoring in the assessment of blood pressure variability are discussed.

Baroreflex effectiveness index: an additional measure of baroreflex control of heart rate in daily life

In healthy subjects, progressive beat-to-beat increases or decreases in systolic blood pressure (SBP) ramps are not always accompanied by baroreflex-driven lengthening or shortening in pulse interval (PI) ramps, respectively. This phenomenon has been quantified by a new index, the baroreflex effectiveness index (BEI), defined as the ratio between the number of SBP ramps followed by the respective reflex PI ramps and the total number of SBP ramps observed in a given time window. Specificity of BEI was shown in eight cats by a -89% reduction of BEI after sinoaortic denervation. In 14 healthy humans, the 24-h average BEI value was 0.21, with a marked day-night modulation ( approximately 0.25 day, approximately 0.15 night) in counterphase with modulation of baroreflex sensitivity (BRS). Our analysis indicates that 1) in normal subjects, arterial baroreflex can induce beat-by-beat PI changes in response to only 21% of all SBP ramps, possibly because of central inhibitory influences or of interferences at sinus node level by nonbaroreflex mechanisms and 2) BEI provides information on the baroreflex function that is complementary to BRS.

[Digestive system neoplasms originating from the autonomic nervous system. Diagnostic, therapeutic and prognostic issues]

The gastrointestinal autonomic nerve tumors (GAN tumor) are uncommon stromal tumors of the intestinal tract and retroperitoneum. The distinction of GAN tumors from other gastrointestinal stromal tumors is based on electron microscopic findings. However further study of additional cases is needed to fully characterize both their gross and microscopic features and to further characterize the natural history of such tumors. In the present study we report two cases of GAN tumor that arose from the stomach and small intestinal with different prognostic evolution in two patients of 73 and 65 years old. They were both treated by surgery, but only one case was successful. In addition patient 1 aged 73, died 11 months after surgical treatment with liver metastases on CT. scan. Patient 2, is clinically well five years after surgical treatment.

Lacidipine and blood pressure variability in diabetic hypertensive patients

The aim of our study was to assess the effects of lacidipine, a long-acting calcium antagonist, on 24-hour average blood pressure, blood pressure variability, and baroreflex sensitivity. In 10 mildly to moderately hypertensive patients with type II diabetes mellitus (aged 18 to 65 years), 24-hour ambulatory blood pressure was continuously monitored noninvasively (Portapres device) after a 3-week pretreatment with placebo and a subsequent 4-week once daily lacidipine (4 mg) or placebo treatment (double-blind crossover design). Systolic blood pressure, diastolic blood pressure, and heart rate means were computed each hour for 24 hours (day and night) at the end of each treatment period. Similar assessments were also made for blood pressure and heart rate variability (standard deviation and variation coefficient) and for 24-hour baroreflex sensitivity, which was quantified (1) in the time domain by the slope of the spontaneous sequences characterized by progressive increases or reductions of systolic blood pressure and RR interval and (2) in the frequency domain by the squared ratio of RR interval and systolic blood pressure spectral power approximately 0.1 and 0.3 Hz over the 24 hours. Compared with placebo, lacidipine reduced the 24-hour, daytime, and nighttime systolic and diastolic blood pressure (P<0.05) with no significant change in heart rate. It also reduced 24-hour, daytime, and nighttime standard deviation (-19.6%, -14.4%, and -24.0%, respectively; P<0.05) and their variation coefficient. The 24-hour average slope of all sequences (7.7+/-1.7 ms/mm Hg) seen during placebo was significantly increased by lacidipine (8.7+/-1.8 ms/mm Hg, P<0.01), with a significant increase being obtained also for the 24-hour average alpha coefficient at 0.1 Hz (from 5.7+/-1.5 to 6.4+/-1.3 ms/mm Hg, P<0.01). Thus, in diabetic hypertensive patients, lacidipine reduced not only 24-hour blood pressure means but also blood pressure variability. This reduction was accompanied by an improvement of baroreflex sensitivity. Computer analysis of beat-to-beat 24-hour noninvasive blood pressure monitoring may offer valuable information about the effects of antihypertensive drugs on hemodynamic and autonomic parameters in daily life.

How to measure baroreflex sensitivity: from the cardiovascular laboratory to daily life

Arterial baroreflex function in humans is commonly assessed through a number of laboratory tests based on quantification of the reflex responses in heart rate or blood pressure to external stimuli applied to the cardiovascular system. Evidence is available that these laboratory estimates of baroreflex sensitivity have both pathophysiological and clinical relevance. Indeed, a number of studies have shown that the sensitivity of the baroreceptor-heart rate reflex may have a prognostic value in myocardial infarction, heart failure and diabetic patients, where mortality seems to be inversely related to the sensitivity of cardiac baroreflex modulation. A deeper insight into the features of daily-life baroreflex cardiovascular control has been offered more recently by techniques based on computer analysis of spontaneous blood pressure and heart rate fluctuations. This innovative approach allows spontaneous baroreflex sensitivity to be assessed in real life conditions, with no need for external stimulation of the patient as required by the older laboratory techniques. This review will briefly survey the methods most widely used to assess baroreflex function in humans, in the laboratory and in daily life.

[Transclavicular approach for delivery of intrathoracic giant goiter. An alternative surgical option]

To remove the immerse portion of a cervical goitre it is necessary to treat preventively the cervical thyroid arteries. In most cases it is afterwards it is easy the blunt finger dissection of the mediastinal bulk following the correct cleavage plane and its dislodging in the cervical area. But in very rare instances, according also to the personal experience, remains some difficulty for the passage of a too bulky and hard mediastinal mass through the rigid limits of the upper thoracic outlet, or the immerse struma is too fragile for pulling it by transfixion threads. Therefore, traditionally arises the opportunity of an additional surgical access, through the breastbone or through the thoracic wall, according to the circumstances. Our experience, completely occasional but extremely positive of two of such cases, induces us to advance a proved alternative surgical proposal. When the difficulty of the removal of the immerse portion of the goitre comes only from the incongruence of the immerse volume and the rigid limits of the upper thoracic outlet, our proposal is that to obtain an amplification of the narrow passage breaking the continuity of the clavicle, by its section beneath the periostium near the breastbone and removing this sternal stump from the joint. The result is that of an widening of the upper thoracic outlet, no more rigid, and making easy the transit of the immerse portion from anterior mediastinum so dislodged in the neck. The rationale of this choice is that all is requested in such cases is only to overcome the obstacle of the incongruence among volume and bulk of the immerse portion and the bone limits fixed from the narrow upper thoracic outlet. Both the traditional sternotomy and the thoracotomy seems disproportional for this purpose, moreover with additional problems during the operation. The true advantage of these classical solutions is in treating under direct vision the anomalous arteries of the mediastinal goitre in cases of ectopic localization. But this is not the case of an immerse cervical goitre. It is therefore essential to note that this proposal applies only to the migrated goitre and not to the ectopic ones. The recovery is extremely simple, and both the aesthetics and the static of the scapular joint are not substantially compromised.

Broad-band spectral analysis of 24 h continuous finger blood pressure: comparison with intra-arterial recordings

The present study compares the spectral characteristics of 24-h blood pressure variability estimated invasively at the brachial artery level with those estimated by measurement of blood pressure at the finger artery using the non-invasive Portapres device. Broad-band spectra (from 3x10(-5) to 0.5 Hz) were derived from both finger and intra-brachial pressures recorded simultaneously for 24 h in eight normotensive and twelve hypertensive ambulant subjects. At frequencies lower than 0.07 Hz, higher spectral estimates were obtained by Portapres than by intra-brachial measurements. The maximum overestimation occurred in systolic pressure at around 10(-2) Hz, where the amplitude of the oscillations was two times greater when measured by Portapres. A less pronounced overestimation was found for diastolic pressures. The maximum overestimation was greater during daytime than during night-time. At around 0.1 Hz, invasive and non-invasive spectra were similar. At the respiratory frequencies (0.15-0.50 Hz), the power spectra were overestimated by Portapres during daytime, and underestimated at night. These results provide reference information for the correct interpretation of Portapres data in the estimation of 24-h blood pressure spectral power.

[The radical treatment of hepatic hydatidosis with deep and multiple locations. The role of new technologies particularly in the case of multiple locations]

Advanced technologies (intraoperative ultrasonography, CT scan, argon coagulator ...) have changed the surgical approach of liver hydatid disease, allowing even multiple or deeply located cysts to be detected and treated successfully. Authors report a series of 4 patients with single (3) or multiple (1) unilocular hepatic cysts; and 1 patient with thoraco-pulmonary hydatid recurrent disease. Treatments of choice and surgical techniques are described. No infective compliances occurred. The mean period of hospitalization was 19 days (ranging between 10 days and 4 weeks). The longest hospitalization was observed in a patient with a post-operative biliary fistula at low out put. Total cysto-pericystectomy is emphasized as the gold standard procedure in the treatment of non complicated unilocular hydatid cysts of the liver. Modern means of investigation and technical equipment make it feasible and safe even in unfavorable localizations, allowing radical removal of the cysts preserving in the meantime all the surrounding liver parenchyma.

[Adrenal incidentaloma: a dopamine-secreting pheochromocytoma with an atypical clinical picture. A case report and review of the literature]

INTRODUCTION

The increasing and consolidated uses of US and CT scan in the diagnosis of abdominal diseases has improved the detection of adrenal asymptomatic masses. Current literature points out that these nodules are identified by 1:100 abdominal CT every year. On the other hand, about 50% of the adrenal tumors are discovered by autopsy. The diagnostic difficulties may be due both to clinical silence and to atypical clinical expressions of the neoplasm--as in the case report--where a pheochromocytoma shows non-specific abdominal symptoms rather than the typical signs of catecholamine overproduction.

CASE REPORT

Author,s report a suprarenal right pheochromocytoma, secreting dopamine prevalently. The tumor showed abdominal symptoms without history of hypertensive paroxysms, or better still in normotension regimen.

DISCUSSION AND CONCLUSIONS

According to current literature, abdominal symptoms occur in about 7% of all suprarenal pheochromocytomas. Most of these tumors prevalently secrete dopamine, that seems to make the prognosis worse. US, CT scan and CT-guided fine needle biopsy weren't able to characterize the real nature of the adrenal incidentaloma. On the contrary, the hormonal screening--by monitoring the urinary VMA and fractioned catecholamines through 24 hours--was decisive for the diagnosis of pheochromocytoma. The adrenal incidentalomas diagnostic significance is tied to the concept that adrenalectomy can change their prognosis, especially in case of pheochromocytoma, where a recovery rate about 90% can be achieved. Authors agree that adrenalectomy my must be performed in all case of "functioning" adrenal tumors and "nonfunctioning" ones with > 6 cm size. Of last years the laparoscopic approach has extended the adrenalectomy's indications to mass with size ranging between 3 and 6 cm., while lesions < 3 cm. size require only a follow up by means of imaging techniques and hormonal monitoring.

[Diagnostic and oncologic updating on gallbladder papilloma. Personal experience and review of the literature]

After a correct definition of the pathologic meaning of "papilloma of gallbladder" and the considerations about the main epidemiologic, pathogenetic and diagnostic guidelines, the authors discuss the meaning of the apparent higher frequency of this pathology in the biliary tract than in the gallbladder localization. This condition probably derives from the precocious appearance of pain or jaundice during choledocal pathology respects to the asymptomatic gallbladder localization. Moreover, using morphological indicators of intracholecistic ultrasonography, the gallbladder's polypoid lesions are divided in group s and for each of the m are indicate d most/actual curative criteria. Currently tendency is to check periodically gallbladder polypoid lesions, and to recure to surgery when the lesion result large more than 1 cm, single, associated with stones, when the patient is older than 50 years and when there is a clear clinical symptomatology. Finally, the authors discuss the malignance evolution of these lesions attaching importance as prognostic role to the study of the K-ras and p-53 proto-oncogenes, because they consider the carcinogenesis like a "multi-step" evolution.