Characterization of nondiffusive transport in plasma turbulence via a novel Lagrangian method

A novel method to probe and characterize the nature of the transport of passive scalars carried out by a turbulent flow is introduced. It requires the determination of two exponents which encapsulate the statistical and correlation properties of the component of interest of the Lagrangian velocities of the flow. Numerical simulations of a magnetically confined, near-critical turbulent plasma, known to exhibit superdiffusive radial transport, are used to illustrate the method. It is shown that the method can easily detect the change in the dynamics of the radial transport that takes place after adding to the simulations a (subdominant) diffusive channel of tunable strength.

Evaluation of the acrosome reaction in human spermatozoa: comparison of cytochemical and fluorescence techniques

The acrosome reaction, which is essential for fertilization, includes fusion and vesiculation of the plasma membrane with the outer acrosomal membrane of spermatozoa, thereby releasing the acrosomal content. Determination of the ability of spermatozoa to undergo the acrosome reaction has proved to be a useful parameter in evaluation of infertile patients. The objective of this study was to compare cytochemical techniques, such as double stain (Giemsa/trypan blue) and triple stain (Bismarck brown/rose bengal/trypan blue), with a fluorescence method using Pisum sativum agglutinin fluorescein conjugate and Hoechst dye N degrees 33258 (double fluorescence). Whereas the cytochemical methods are easy to perform in general laboratories, the fluorescence technique requires special and costly instrumentation. In semen obtained from fertile donors, spermatozoa were selected by the swim-up technique and the acrosome reaction was induced by incubation at low temperature. The percentages of vital and acrosome-reacted spermatozoa were determined after incubation at 4 degrees C and at room temperature. No statistically significant difference was found between double fluorescence (viability 86.3%, acrosome reaction 14.7%) and triple stain (viability 85.3%, acrosome reaction 17%) (P > 0.05). On the other hand, the double stain technique showed different values for viability (70.3%) and acrosome reaction (42.5%) (P < 0.05). In conclusion, triple stain yielded results similar to those obtained by the fluorescence technique in evaluating the acrosome reaction and can therefore easily be used in general or research laboratories.

Acrosomal status and mitochondrial activity of human spermatozoa vitrified with sucrose

This study investigates the ability of sucrose to protect spermatozoa against mitochondrial damage, artificial cryoinduction of capacitation, and acrosome reaction. Spermatozoa were isolated using the swim-up procedure performed using three different media: (a) human tubal fluid (HTF, control) medium; (b) HTF with 1% human serum albumin (HSA); and (c) HTF with 1% HSA and 0.25 M sucrose. From each group, 30 mul suspensions of cells were dropped directly into liquid nitrogen and stored for at least 24 h. Cells were thawed by quickly submerging the spheres in HTF with 1% HSA at 37 degrees C with gentle agitation. Sperm motility, viability, mitochondrial membrane potential integrity, spontaneous capacitation, and acrosome reaction were investigated. Sperm viability, acrosome reaction, and capacitation were detected using the double fluorescence chlortetracycline-Hoechst 33258 staining technique. Mitochondrial function was evaluated using a unique fluorescent cationic dye, 5,5',6,6'-tetrachloro-1-1',3,3'-tetraethyl-benzamidazolocarbocyanin iodide, commonly known as JC-1. The number of progressively motile spermatozoa was significantly higher in the sucrose-supplemented medium group (57.1+/-3.2%, P<0.05) when compared with controls (19.4+/-1.9%). The combination of HSA and sucrose (65.2+/-2.6%) has a stronger cryoprotective effect on the integrity of mitochondrial membrane potential (P<0.05) compared with HSA alone (32.6+/-4.7%). In conclusion, vitrification of human spermatozoa with non-permeable cryoprotectants such as HSA and sucrose can effectively cryopreserve the cells without significant loss of important physiological parameters.

Clinical outcome in patients with venous thromboembolism and hidden cancer: findings from the RIETE Registry

INTRODUCTION

Although extensive screening in patients with venous thromboembolism (VTE) may result in early identification of hidden cancer, it is unknown whether the prognosis of these patients may be favorably influenced.

PATIENTS AND METHODS

RIETE is an ongoing, prospective registry of consecutive patients with objectively confirmed, symptomatic, acute VTE. We compared the 3-month outcome of patients with hidden cancer with that in patients in whom no symptoms of cancer were noted.

RESULTS

Of 17,475 patients with acute VTE, 2852 (16%) had cancer diagnosed before VTE or during admission. Hidden cancer was detected in 178 (1.2%) of the remaining 14,623 patients. The most common sites were lung, prostate, colorectum, or hematologic, and 51% had metastases. As compared with patients in whom no symptoms of cancer were noted, those with hidden cancer had an increased incidence of recurrent VTE (11.4% vs. 2.1%; P < 0.001), major bleeding (5.1% vs. 2.1%; P = 0.007), and mortality (20% vs. 5.4%; P < 0.001). In the multivariate analysis, patients aged 60-75 years [odds ratio 1.8; 95% CI 1.2-2.7], with idiopathic VTE (odds ratio 3.0; 95% CI 2.2-4.2), with bilateral thrombosis (odds ratio 2.3; 95% CI 1.3-4.1) or with anemia (odds ratio 1.9; 95% CI 1.4-2.6) were at an increased risk for hidden cancer.

CONCLUSIONS

VTE patients with hidden cancer have an increased incidence of recurrences, major bleeding or death during the first 3 months of therapy. With four simple, easily obtainable variables, it is possible to identify a subgroup of VTE patients with a higher risk for hidden cancer.

[Novelties in the field of progression factors in chronic kidney disease]

The fight against chronic kidney disease is one of the most relevant aspects of nephrological practice, from both the perspective of clinical activity and research within the field of nephrology. In this brief article, we present in very summarized form some of the aspects in this field in the last year that the authors found of interest. Because the content of the next few pages was necessarily chosen on the basis of the authors' preferences, we assume that many other topics of great interest have been left out of this summary. In any case, we hope that this article will be interesting and useful and also serve as an subject of debate in nephrology forums.

[Is chronic kidney disease (CKD) a problem of great epidemiological relevance?]

In this article some of the novelties published in 2007 on epidemiological aspects of chronic kidney disease are reviewed. Specifically, some studies on the suitability of current methods for measurement of glomerular filtration rate, the estimated current prevalence of chronic kidney disease and the influence of age and NSAIDs on progression of this disease are discussed. Finally, various recent publications on the role of chronic kidney disease as a cardiovascular risk factor are summarized.

Fractional generalization of Fick's law: a microscopic approach

In the study of transport in inhomogeneous systems it is common to construct transport equations invoking the inhomogeneous Fick law. The validity of this approach requires that at least two ingredients be present in the system. First, finite characteristic length and time scales associated with the dominant transport process must exist. Second, the transport mechanism must satisfy a microscopic symmetry: global reversibility. Global reversibility is often satisfied in nature. However, many complex systems exhibit a lack of finite characteristic scales. In this Letter we show how to construct a generalization of the inhomogeneous Fick law that does not require the existence of characteristic scales while still satisfying global reversibility.

Clinical outcome in patients with venous thromboembolism and hidden cancer: findings from the RIETE Registry

INTRODUCTION

Although extensive screening in patients with venous thromboembolism (VTE) may result in early identification of hidden cancer, it is unknown whether the prognosis of these patients may be favorably influenced.

PATIENTS AND METHODS

RIETE is an ongoing, prospective registry of consecutive patients with objectively confirmed, symptomatic, acute VTE. We compared the 3-month outcome of patients with hidden cancer with that in patients in whom no symptoms of cancer were noted.

RESULTS

Of 17,475 patients with acute VTE, 2852 (16%) had cancer diagnosed before VTE or during admission. Hidden cancer was detected in 178 (1.2%) of the remaining 14,623 patients. The most common sites were lung, prostate, colorectum, or hematologic, and 51% had metastases. As compared with patients in whom no symptoms of cancer were noted, those with hidden cancer had an increased incidence of recurrent VTE (11.4% vs. 2.1%; P < 0.001), major bleeding (5.1% vs. 2.1%; P = 0.007), and mortality (20% vs. 5.4%; P < 0.001). In the multivariate analysis, patients aged 60-75 years [odds ratio 1.8; 95% CI 1.2-2.7], with idiopathic VTE (odds ratio 3.0; 95% CI 2.2-4.2), with bilateral thrombosis (odds ratio 2.3; 95% CI 1.3-4.1) or with anemia (odds ratio 1.9; 95% CI 1.4-2.6) were at an increased risk for hidden cancer.

CONCLUSIONS

VTE patients with hidden cancer have an increased incidence of recurrences, major bleeding or death during the first 3 months of therapy. With four simple, easily obtainable variables, it is possible to identify a subgroup of VTE patients with a higher risk for hidden cancer.

Low 25-hydroxyvitamin D concentrations in obese women: their clinical significance and relationship with anthropometric and body composition variables

Obesity is associated with low concentrations of 25-hydroxyvitamin D [25(OH) D]. However, conflicting results have been found regarding the relationship of 25(OH) D with anthropometric and adiposity parameters. The aim of our study was to analyze the association between 25(OH) D and body fat (BF) in a homogeneous cohort of non-obese, obese, and morbidly obese Caucasian women. The study was performed in L'Hospitalet de Llobregat, a city adjacent to Barcelona with a latitude of 41 degrees, 22 minutes, and 5 seconds north.

MATERIALS AND METHODS

Plasma concentrations of 25(OH) D were determined and body composition was evaluated by bioelectrical impedance in a group of 43 women with morbid obesity, 28 non-morbidly obese, and 50 non-obese women matched for age.

RESULTS

Morbidly obese women showed lower 25(OH) D concentrations compared to non-morbidly and non-obese women (37.9+/-16 vs 40.2+/-13 vs 56.7+/-21 nmol/l, p=0.001). Fifty-one percent of morbidly obese women had vitamin D deficiency [25(OH) D<38 nmol/l] compared to 22% of non-obese patients, (p=0.004). In the bivariate correlation analysis 25(OH) D was inversely associated with weight (r=-0.41, p=0.001), body mass index (BMI) (r=-0.432, p=0.001), waist to hip ratio (WHR)(r=-0.40, p=0.001), BF (r=-0.53, p=0001), fat mass (r=-0.44, p=0.0001), fat-free mass (r=-0.35, p=0.001). In the multivariate general linear model analysis, 25(OH) D was associated with season of examination (p=0.001) and was negatively associated with BF (beta=-0.75, p=0.001), after adjusting for age, BMI, and WHR.

CONCLUSIONS

25(OH) D concentrations are associated with body composition variables especially by BF, independently of seasonal variability. Therefore, body adiposity should be considered when assessing vitamin D requirements in obese patients.

Course of Patients With Chronic Hepatitis C Virus Infection Undergoing Heart Transplantation

OBJECTIVE

The objective of this study was to describe the clinical course of patients with chronic hepatitis C virus (HCV) infection undergoing heart transplantation (HT).

MATERIALS AND METHODS

Among 499 patients transplanted in our hospital between January 1989 and September 2006, 11 subjects (2.2%) had chronic HCV infection. We analyzed liver function laboratory parameters pretransplantation as well as at 3, 6, 12 months, and last available, pre- and postsurgical hepatobiliary ultrasounds, and mortality. The mean time since HT was 32 +/- 23 months.

RESULTS

No abnormalities in the liver parenchyma were observed on the ultrasound examinations performed before or after transplantation. There were 3 deaths (27%), none of which was related to HCV infection. Liver function laboratory parameters remained stable during the follow-up.

CONCLUSIONS

The clinical course of patients with chronic HCV infection undergoing HT whose presurgical assessment did not show significant liver damage was favorable. No morphological or laboratory abnormalities were observed that would suggest reactivation of the infection during the follow-up.

Mortality After Heart Transplantation in Adults With Congenital Heart Disease: A Single-Center Experience

The number of congenital heart disease (CHD) patients transplanted to date is small. The results are comparable to those undergoing heart transplantation (HT) for other etiologies. However, advances in pediatric surgery over recent years (eg, the Fontan procedure) has increased the demand for HT by a growing number of children who reach adulthood and who also have a different profile. We analyzed the clinical profile and survival of our CHD patients compared with other etiologies.

MATERIALS AND METHODS

From July 17, 1991 to December 31, 2006, eight HT were performed in our center for CHD. A descriptive study determined the baseline characteristics and survival of these patients, compared with those of the overall transplant group and other subgroups (dilated cardiomyopathy, ischemic heart disease).

RESULTS

Mean age was 26 years. Four (50%) CHD patients were diagnosed with single-ventricle anatomy, associated or not with other lesions; none had been operated with the Fontan procedure. Two patients died prematurely. Early, 1-, and 10-year survival was 75% at each time point. Early, 1-, and 10-year survival in the group with other diagnoses was 90%, 78%, and 60%, respectively, and in the dilated cardiomyopathy group it was 94%, 86%, and 72%, respectively.

CONCLUSION

The current number of CHD transplant patients was small and young. The most common etiology was single-ventricle anatomy without a prior Fontan operation. Overall survival was comparable to HT for dilated cardiomyopathy.

Analysis of the Impact of Donor Gender on Early Mortality

INTRODUCTION

Many studies have shown a detrimental effect of female donor gender on heart transplantation (HT) outcome.

OBJECTIVE

We retrospectively evaluated our experience in HT to determine the effect of donor gender on early survival.

MATERIALS AND METHODS

We divided the sample of 464 primary HT from November 1997 to September 2006 into 4 groups: G1, female donor to a male recipient; G2, male donor to a male recipient; G3, male donor to female recipient; and G4, female donor to a female recipient. We performed a descriptive study of the baseline characteristics. The chi(2) test was used to determine differences in early mortality (30 days) between groups and a multivariate analysis to identify confounding factors to increase mortality.

RESULTS

Although the univariate study showed that G1 showed a significantly lower early survival rate (84%) than G2 (91%), the multivariate study adjusted for donor and recipient weight and size, urgency level, previous surgery, and age only showed urgency level (odds ratio [OR] 2.6; 95% confidence interval [CI] 1.2-5.57; P = .016) and previous surgery (OR 5.8; 95% CI 2.7-12.4; P < .01) to be predictors of early mortality. When baseline characteristics were analyzed, we found that 31% of HT in G1 were urgent versus 18% in G2, and 32% of patients in G1 had previous surgery versus 17% in G2.

CONCLUSIONS

Donor gender did not appear to negatively affect early survival. In our series, urgent HT in male recipients with a female was more frequent than with a male donor heart. The higher early mortality in male recipients of an urgent HT from a female than from a male donor was attributable to a higher baseline risk profile.

A new technique to evaluate the ability of cryoprotectors to prevent premature acrosome reaction in human spermatozoa

Acrosome reaction (AR) induced by low temperature has been used to evaluate sperm function; it correlates adequately with the fertilization percentages in vitro. In this study, the technique of AR induction by low temperature was used to evaluate the effect in the protection of the acrosome by cryopreservatives normally used in human semen cryopreservation. Donor sperm selected by use of the migration sedimentation technique was incubated in human tubal fluid medium, added to dimethyl sulphoxide 1 m, ethylene glycol 0.75 m, glycerol 1 m, incubated at 4 degrees C and 20 degrees C (as a control) for 18 h, and then for 3 h at 37 degrees C in a cell incubator. The AR was evaluated by triple stain in 100 viable spermatozoa. The effect of cryopreservatives on acrosome preservation in samples incubated for 18 h at 4 degrees C was as follows: 78% intact acrosome for glycerol, 77.8% intact acrosome for dimethyl sulphoxide and 96.2% intact acrosome for ethylene glycol (P < 0.0025 compared with glycerol and dimethyl-sulphoxide). The sperm samples incubated with cryopreservatives for 18 h at 20 degrees C did not show an increase in the percentage of AR in samples incubated with glycerol and ethylene glycol, while a significant variation was observed in the sample incubated with dimethyl sulphoxide (P < 0.001). Additional incubation for 3 h at 37 degrees C significantly increased the AR only in the sample incubated with glycerol (P < 0.001). Acrosome preservation is essential in the fertilization process and the evaluation of acrosome reaction induction by low temperature test was satisfactory. This test proves that ethylene glycol presents a greater protective effect on the acrosome preservation of human spermatozoa.

Enhanced production of runaway electrons during a disruptive termination of discharges heated with lower hybrid power in the Frascati Tokamak Upgrade

We report on the observation of a large production of runaway electrons during a disruptive termination of discharges heated with lower-hybrid waves at the Frascati Tokamak Upgrade. The runaway current plateaus, which can carry up to 80% of the predisruptive current, are observed more often than in normal Ohmic disruptions. The largest runaway currents correspond to the slowest plasma current decay rates. This trend is opposite to what is observed in most tokamaks. We attribute this anomalous behavior to the acceleration of the preexistent wave-resonant suprathermal electrons during the disruption decay phase. These results could be relevant for the operation of the ITER tokamak whenever a sizeable amount of lower-hybrid power is made available.

[Insight, neurocognition and psychopathology in schizophrenia]

INTRODUCTION

In recent years, research has been aimed at finding variables mediating between neurocognition and psychosocial functioning in schizophrenia, proposing insight as one of these variables. Some authors have found associations between insight and functional outcome, and between insight and symptomatology, although these associations remain unclear. These different findings could be explained by the insight definition used. The current study evaluates insight unidimensionally and multidimensionally and studies its relationship with cognitive and psychopathological variables.

METHODS

The sample consisted of 94 subjects admitted to an outpatient Psychosocial Rehabilitation Program, all diagnosed of schizophrenia according to ICD-10 diagnostic criteria. A brief version of the Neuropsychology Battery Test Barcelona and the Wisconsin Card Sorting Test were used to evaluate cognitive variables. The Positive and Negative Syndrome Scale (PANSS) was used to evaluate psychopathology. Insight was assessed with the PANSS item ((lack of judgment and insight)), and with a semi-structured interview.

RESULTS

Two insight factors were found, one including more specific knowledge about the disease and its consequences (cognitive factor), that is related to executive functions, and another referring to unspecific knowledge about suffering from an illness and the need for treatment (psychotic factor). Each factor was statistically related to positive symptoms and superior cognitive functions.

CONCLUSIONS

These findings support a relationship between insight and low cognitive performance.

Renormalization of tracer turbulence leading to fractional differential equations

For many years quasilinear renormalization has been applied to numerous problems in turbulent transport. This scheme relies on the localization hypothesis to derive a linear transport equation from a simplified stochastic description of the underlying microscopic dynamics. However, use of the localization hypothesis narrows the range of transport behaviors that can be captured by the renormalized equations. In this paper, we construct a renormalization procedure that manages to avoid the localization hypothesis completely and produces renormalized transport equations, expressed in terms of fractional differential operators, that exhibit much more of the transport phenomenology observed in nature. This technique provides a first step toward establishing a rigorous link between the microscopic physics of turbulence and the fractional transport models proposed phenomenologically for a wide variety of turbulent systems such as neutral fluids or plasmas.

Naevus lipomatosus cutaneous superficialis on the nose

Naevus lipomatosus cutaneous superficialis (NLCS) is an uncommon hamartomatous lesion with an exceptional presentation on the face. We report the case of an elderly patient who presented with a classic type of NLCS on the right nasal orifice. This patient was taking inhaled steroids for his allergic rhinitis during 35 years.

Nuclear charge radii of 9,11Li: the influence of halo neutrons

The nuclear charge radius of 11Li has been determined for the first time by high-precision laser spectroscopy. On-line measurements at TRIUMF-ISAC yielded a 7Li-11Li isotope shift (IS) of 25 101.23(13) MHz for the Doppler-free [FORMULA: SEE TEXT]transition. IS accuracy for all other bound Li isotopes was also improved. Differences from calculated mass-based IS yield values for change in charge radius along the isotope chain. The charge radius decreases monotonically from 6Li to 9Li, and then increases from 2.217(35) to 2.467(37) fm for 11Li. This is compared to various models, and it is found that a combination of halo neutron correlation and intrinsic core excitation best reproduces the experimental results.

[Cerebrospinal fluid drainage in endovascular repair of thoracic aortic lesions: preliminary report of experience with 5 patients]

Endovascular repair of thoracic or thoracoabdominal aortic lesions as an alternative to open surgery, to avoid the high complication and mortality rates associated with the conventional approach, does not eliminate the risk of postoperative paraplegia. We report on a series of 5 patients with different thoracic aortic lesions who underwent endovascular stent-graft repair procedures. We describe measures to drain cerebrospinal fluid to prevent ischemic spinal cord injury. We also review the anesthetic management of patients undergoing this type of surgery.

[Treatment of acute lithium intoxication with high-flux haemodialysis membranes]

Lithium carbonate is commonly prescribed for the treatment of bipolar (manic-depressive) disorders. However, because of its narrow therapeutic index an excessive elevation of serum lithium concentration, either during chronic maintenance therapy or after an acute overdose, can result in serious toxicity. In addition to supportive care, the established treatment of severe lithium toxicity is haemodialysis. Conventional haemodialysis can reduce serum lithium rapidly, but post-dialysis rebound elevations with recurrent toxicity have been documented in old publications. High-flux membranes should be capable of removing more lithium per hour of haemodialysis, but published values are not available. We report here three patients with acute lithium intoxication who were treated successfully with bicarbonate and high-flux haemodialysis membranes. Our patients presented with a severe degree of intoxication, based on the amount of drug ingested, the initial serum lithium level, the severity of neurologic symptoms and systemic manifestations. Two patients developed acute renal failure probably as a result of volume depletion since it was rapidly reversible by haemodialysis and infusion therapy. In addition, consecutive haemodialysis sessions and improvement of renal function allowed a rapid decrease in serum lithium levels without haemodynamic instability or rebound elevations in lithium concentration. The effectiveness of the procedure in these cases can be attributed to the use of bicarbonate dialysate and high-efficiency dialysers. This is the first report describing the effect of high-efficiency dialysers on lithium pharmacokinetic. Using this technique the elimination rate of lithium was found to be greater than previously reported with haemodialysis.

Ambulatory blood pressure monitoring in patients with hyperthyroidism before and after control of thyroid function

BACKGROUND AND OBJECTIVE

Thyroid hormones have pronounced effects on the cardiovascular system. Thyrotoxicosis affects blood pressure (BP), modifying both diastolic (DBP) and systolic (SBP) pressures. There are no studies examining BP with ambulatory blood pressure monitoring (ABPM) in hyperthyroidism before and after control of thyroid function. Our aims were (1) to analyse ABPM in a group of normotensive hyperthyroid patients before and after normalizing circulating thyroid hormones and (2) to compare these results with those obtained in a group of euthyroid subjects.

PATIENTS AND MEASUREMENTS

We studied 20 normotensive hyperthyroid subjects [18 women; age (mean +/- SEM) 49.0 +/- 3.0 years] and 15 healthy subjects. Patients were evaluated by ABPM over 24 h, at diagnosis and after therapy (n = 18).

RESULTS

The average 24-h, daytime and night-time SBP was significantly greater in hyperthyroid patients than in controls with no significant differences in DBP. Circadian BP rhythm, estimated by the difference between mean values of SBP, DBP and mean BP during daytime and night-time, was unchanged. The average 24-h and daytime SBP significantly decreased after normalizing thyroid function in the 18 hyperthyroid evaluated patients. Daytime SBP and DBP were higher than night-time values both before and after control of thyroid function. However, no differences in circadian BP rhythm were observed.

CONCLUSIONS

Normotensive hyperthyroid patients exhibit higher ambulatory SBP throughout 24 h than normotensive euthyroid subjects. Control of hyperthyroidism decreases ambulatory SBP values. Mean nocturnal fall in BP is comparable in normotensive hyperthyroid patients and control subjects.

[Role of peritoneal drainage in very low birth weight with enterocolitis]

Peritoneal drainage (PD) has been proposed as a temporizing procedure for perforated necrotizing enterocolitis (NEC) in very low birth weight neonates. This operation was designed for patients considered too unstable to undergo laparotomy (LAP). Since the introduction of PD some investigators have suggested that it may serve as a definitive therapy. The aim of our study is to determine the efficacy of PD for the stabilization of patients with complicated NEC and its utility as a definitive surgical treatment.

METHODS

We review the clinical records from all the patients treated in our unit because of NEC that required surgical therapy. We analyze the mean blood pressure, cardiac and respiratory rate, inspired oxygen concentration, mean airway pressure, diuresis, and arterial blood gases measured 6 and 12 hours after the initial surgical treatment. We divide patients in two different groups according to the initial surgical procedure, peritoneal drainage (PD) or laparotomy group (LAP). Data is shown as media +/- standard deviation, statistical analyses were performed using analysis of variance (ANOVA) for repeated measures and Mann-Withney test.

RESULTS

From January 1997 to January 2001 we treated 13 patients with necrotizing enterocolitis that required surgical treatment. Among this group 6 patients were managed initially with PD and 7 with LAP. The gestational age media was 29.07 +/- 3.81 weeks and the birth weight mean 1199.76 +/- 521 gr., without any significant differences between the two groups DP and LAP. All patients improved haemodynamically and respiratory 6 and 12 hours after the surgical treatment. Nevertheless, the mean blood pressure improved even more in the DP group (p<0.005). The DP group showed an improvement in all parameters 6 hours after the drainage was placed, but this effect wasn't maintained for the next 12 hours onwards. From the 12 hours after PD all patients suffered a steady worsening that required further surgical procedures. The overall mortality was 3 patients (23%), without differences between the two groups. The surgical techniques performed (bowel resection, diversion) were similar for both groups.

DISCUSSION

DP allows the stabilization for very critically ill patients with complicated NEC. However, this stabilization is temporary. This improvement lasts for a few hours providing a better status for the definitive surgical treatment for the perforated NEC. In our experience DP could not be considered as a definitive surgical treatment.

Pyrrolidon carboxypeptidase activities in the hypothalamus-pituitary-thyroid and hypothalamus-pituitary-ovary axes of rats with mammary gland cancer induced by N-methyl nitrosourea

Pyrrolidon carboxypeptidase is an omega-peptidase that hydrolyses N-terminal pyroglutamyl residues from biologically active peptides such as gonadotropin-releasing and thyrotrophin-releasing hormones. We previously described a decrease in both rat and human pyrrolidon carboxypeptidase activity with breast cancer, suggesting that gonadotropin-releasing hormone may be an important local intracrine, autocrine and/or paracrine hormonal factor in the pathogenesis of breast cancer while playing a role in the tumoral process. However, the other susceptible substrate of pyrrolidon carboxypeptidase, thyrotrophin-releasing hormone, may also be modified with breast cancer, supporting an association between breast cancer and thyroid disorders. The present work analyses soluble and membrane-bound pyrrolidon carboxypeptidase activities in the hypothalamus-pituitary-thyroid and hypothalamus-pituitary-ovary axes in N-methyl nitrosourea-induced breast cancer in rats. Our aim was to determine the possible relationship between gonadotropin-releasing hormone and thyrotrophin-releasing hormone regulation through pyrrolidon carboxypeptidase activity. We propose that pyrrolidon carboxypeptidase activity dysregulation at various local and systemic levels may participate in the initiation, promotion and progression of breast cancer induced in rat by N-methyl nitrosourea through the increase in gonadotropin-releasing hormone. Since pyrrolidon carboxypeptidase activity also acts on thyrotrophin-releasing hormone, the dysregulation of this enzyme's activity could indirectly affect hypothalamus-pituitary-thyroid axis function, and thus potentially represent a link between the diseases of thyroid and breast cancer.

[Tubulointerstitial nephritis associated with treatment with selective Cox-2 inhibitors, celecoxib and rofecoxib]

The nephrotoxic effect of nonselective nonsteroidal anti-inflamatory drugs (NSAIDS) has been widely described. The main benefit of the Cox-2 inhibitors in relation to the NSAIDS is the production of a very similar analgesic effect, but with fewer gastrointestinal side effects. However, their effects on renal function are little known as yet and their long-term safety is still pending definition. The use of selective Cox-2 inhibitors as anti-inflamatory analgesic is becoming more and more common in our environment. We report two cases of tubulointersticial nephritis confirmed by renal biopsy, associated with administration of the two Cox-2 inhibitors currently available on the market, celecoxib and rofecoxib. In both cases, we were talking about elderly women, with deterioration of the general condition and acute renal failure. In the former case, renal biopsy showed an acute tubulo-intersticial nephritis (TIN) so highly "variegated" in its histologic expression. In the second case, was associated with strong indications of chronicity. Treatment with steroid was initiated in both patients and improvement of renal function was observed.

Fluid limit of nonintegrable continuous-time random walks in terms of fractional differential equations

The fluid limit of a recently introduced family of nonintegrable (nonlinear) continuous-time random walks is derived in terms of fractional differential equations. In this limit, it is shown that the formalism allows for the modeling of the interaction between multiple transport mechanisms with not only disparate spatial scales but also different temporal scales. For this reason, the resulting fluid equations may find application in the study of a large number of nonlinear multiscale transport problems, ranging from the study of self-organized criticality to the modeling of turbulent transport in fluids and plasmas.

Alpha-glucosidase in the human epididymis: topographic distribution and clinical application

Alpha-glucosidase activity (EC.3.2.1.20) is present in human seminal plasma, and the neutral form of the enzyme originates almost exclusively from the epididymis. In this study, the specific immunocytochemical location of alpha-glucosidase in the human epididymis was evaluated using a polyclonal antibody. Furthermore, a spectrophotometric assay was employed to assess epididymal obstruction in infertile patients. The enzymatic activity of alpha-glucosidase free of prostate isoform (AGFPI) was determined spectrophotometrically at 405 nm. According to AGFPI activity, patients with leucocytospermia, oligozoospermia and azoospermia were recorded as having normal values or low values indicating epididymal obstruction. Specific immunochemistry staining was demonstrated in the cytoplasmic cells at the epithelial level, in the transition area and in the efferent ducts. The values of the three groups and the control were as follows (mean +/- SEM): normozoospermia (control): 20.2 +/- 1.4 mU ml(-1); azoospermia: normal value: 17.6 +/- 2.2 mU ml(-1), low value: 7.4 +/- 1.8 mU ml(-1); oligozoospermia: normal value: 22.3 +/- 2.5 mU ml(-1), low value: 7.3 +/- 0.7 mU ml(-1); leucocytospermia: increase value: 38.9 +/- 3.7 mU ml(-1), low value: 11.1 +/-1.3 mU ml(-1). This study suggests that determination of alpha-glucosidase might be helpful to evaluate functions of the epididymis and particularly to exclude epididymal obstruction.