Cysteamine-bicalutamide combination therapy corrects proximal tubule phenotype in cystinosis.

Nephropathic cystinosis is a severe monogenic kidney disorder caused by mutations in CTNS, encoding the lysosomal transporter cystinosin, resulting in lysosomal cystine accumulation. The sole treatment, cysteamine, slows down the disease progression, but does not correct the established renal proximal tubulopathy. Here, we developed a new therapeutic strategy by applying omics to expand our knowledge on the complexity of the disease and prioritize drug targets in cystinosis. We identified alpha-ketoglutarate as a potential metabolite to bridge cystinosin loss to autophagy, apoptosis and kidney proximal tubule impairment in cystinosis. This insight combined with a drug screen revealed a bicalutamide-cysteamine combination treatment as a novel dual-target pharmacological approach for the phenotypical correction of cystinotic kidney proximal tubule cells, patient-derived kidney tubuloids and cystinotic zebrafish.

Expression profiles in surgically-induced carotid stenosis: a combined transcriptomic and proteomic investigation.

Vascular injury aimed at stenosis removal induces local reactions often leading to restenosis. The aim of this study was a concerted transcriptomic-proteomics analysis of molecular variations in a model of rat carotid arteriotomy, to dissect the molecular pathways triggered by vascular surgical injury and to identify new potential anti-restenosis targets. RNA and proteins extracted from inbred Wistar Kyoro (WKY) rat carotids harvested 4 hrs, 48 hrs and 7 days after arteriotomy were analysed by Affymetrix rat microarrays and by bidimensional electrophoresis followed by liquid chromatography and tandem mass spectrometry, using as reference the RNA and the proteins extracted from uninjured rat carotids. Results were classified according to their biological function, and the most significant Kyoro Encyclopedia of Genes and Genomes (KEGG) pathways were identified. A total of 1163 mRNAs were differentially regulated in arteriotomy-injured carotids 4 hrs, 48 hrs and 7 days after injury (P < 0.0001, fold-change > or =2), while 48 spots exhibited significant changes after carotid arteriotomy (P < 0.05, fold-change > or =2). Among them, 16 spots were successfully identified and resulted to correspond to a set of 19 proteins. mRNAs were mainly involved in signal transduction, oxidative stress/inflammation and remodelling, including many new potential targets for limitation of surgically induced (re)stenosis (e.g. Arginase I, Kruppel like factors). Proteome analysis confirmed and extended the microrarray data, revealing time-dependent post-translational modifications of Hsp27, haptoglobin and contrapsin-like protease inhibitor 6, and the differential expression of proteins mainly involved in contractility. Transcriptomic and proteomic methods revealed functional categories with different preferences, related to the experimental sensitivity and to mechanisms of regulation. The comparative analysis revealed correlation between transcriptional and translational expression for 47% of identified proteins. Exceptions from this correlation confirm the complementarities of these approaches.

Perioperative optic neuropathy following off-pump coronary artery bypass grafting.

Visual loss from ischemic perioperative optic neuropathy (PON) rarely occurs during the postoperative period of patients undergoing cardiac surgery. Since the first description, PON has been associated with cardiopulmonary bypass (CPB), being some CPB-related complications and epiphenomena considered the causes of such terrible complication. In particular, the risk for micro-embolization during aortic cannulation and clamping, the CPB-related inflammatory response, the hemodilution and the hypothermia during CPB could be responsible of PON. However, some cases of PON still remain idiopathic. We report here a very rare case of PON following off-pump surgery in a patient with severe coronary disease and multiorgan comorbidities. The case reported opens the debate on the potential mechanisms underlying PON, other than cardiopulmonary bypass.

Lung transplantation by continuous perfusion in an experimental auto-transplant animal model.

OBJECTIVE: The aim of this study was to evaluate the preservation of the lung using the cold flushing technique in association with continuous perfusion of the organ during static hypothermic storage. METHODS: In the first phase, the hearts and lungs of 5 New Zealand rabbits were removed three hours after establishing brain death. The left lungs were each conserved in 200 ml of low-potassium UW solution at 10 degrees C for 3 hours of cold ischemia (control group I). The right lungs were also placed in cold storage but were perfused continuously for three hours with low-potassium UW solution at 10 degrees C (group II). In the second phase, ten rabbits underwent a right lung auto-transplant. Lungs were conserved using two techniques. Histoenzymatic and pathological tests were performed: lung function was evaluated. RESULTS: In the first phase the histopathological examination carried out at the end of storage revealed fewer ischemic alterations in the second group compared to the first. In the second phase a significant hypoxia was observed in group I when both lungs and the right lung only were perfused. The histopathological examination revealed ischaemia/reperfusion lesions in both groups though mainly in group I and a good level of ATPase activity in group II though these results were not significant. CONCLUSIONS: Cold flushing of the pulmonary artery and continuous perfusion during static hypothermic storage appears to guarantee a better partial arterial pressure of oxygen in this model of auto-transplant compared to the classical cold storage method.

Intravascular hemolysis after mitral and aortic valve replacement with different types of mechanical prostheses.

Heart valve replacement with mechanical prosthesis is associated with mild intravascular hemolysis. In this study we evaluated the incidence of hemolysis in patients with different combinations of two mechanical valves. Between 1974 and 1996, 680 patients underwent mitral and aortic valve replacement with mechanical prostheses; we selected 90 patients, divided into six groups according to the prosthetic model (Group A, ball and tilting disc; Group B, ball and bileaflet; Group C, tilting disc and tilting disc; Group D, tilting disc and bileaflet; Group E, bileaflet and tilting disc; Group F, bileaflet and bileaflet; respectively, in mitral and aortic position). Blood tests were performed to check blood hemoglobin, serum lactic dehydrogenase, percent-correlated reticulocyte fraction, serum haptoglobin, and schistocytes. Chi square test was performed for categorical data. ANOVA and Bonferroni tests were performed in order to evaluate significant statistical differences between media and variance of the hematological data. A mild degree of intravascular hemolysis was observed in 30% of patients with double mechanical prostheses. LDH values were above the normal values in all groups, although a significant difference was found only between Group B versus Groups C and D. Reticulocytes and schistocytes and serum haptoglobin values were within the normal range and no differences were found between the groups. Low levels of blood hemoglobin were found in Groups D and F. The difference was statistically significant when compared with Groups A and E. In conclusion, hemolysis is frequent but never severe in patients with mitral and aortic mechanical prostheses. A higher incidence of subclinical hemolysis was found in patients with bileaflet valves regardless of the position of the implant.

[Brain death: myocardial consequences, an experimental study on pigs]. / La morte cerebrale: conseguenze miocardiche, studio sperimentale nel maiale.

It is well known that brain death is responsible for major problems encountered in the clinical setting that may alter heart graft viability before transplantation. To investigate these myocardial dysfunctions, a model of brain death was prepared in pigs. Anaesthetised pigs were ventilated with FiO2 of 50% through an endotracheal tube. Animals were monitored by measuring systemic arterial pressure, pulmonary artery pressure, cardiac output, left ventricular developed pressure and dP/dT (Millar probe), cardiac contractility (sonomicrometers crystals), ECG, myocardial tissue oedema (impedance spectroscopy) and heart rate. Blood samples were drawn to assess arterial blood gases, serum electrolytes, plasma catecholamine levels, LDH isoenzymes and ascorbil free radicals production. Myocardial high energy contents (adenosine triphosphate, creatine phosphate) were measured by spectroscopy MRI. After 30 minutes stabilisation, brain death was induced by ligation of the supra-aortic vessels. To assess myocardial impairment all the parameters mentioned were recorded at baseline, 1', 30', 60', 120' and 180' following the brain death. Results showed initial tachycardia and a significant increase (p < 0.05) in cardiac function at 1' and 30', related to the cathecolamine level variations, followed by a significant depression (p < 0.05) of cardiac contractility by the end of the third hour; there was no modification whatsoever of myocardial high energy contents and of ascorbil free radical and LDH isoenzymes productions. In this pig model of brain death the observed myocardial dysfunction was directly related to the induced catecholamine secretion without any myocardial high energy substrate depletion up until 180'. Such results could be taken into account when evaluating a donor heart, allowing to use organs judged nowadays not feasible, and could be of some help in lowering the number of the "défaillances" of the transplanted hearts.

[A case of cholesterol crystal embolism following coronarography: a contraindication of the procedure?]. / Su di un caso di embolia da cristalli di colesterolo successiva a coronarografia: controindicazione all'intervento?

Authors report on one patient with cholesterol embolization following cardiac catheterization and coronary by-pass surgery. During the immediate post-operative period, neurological and renal complications occurred because of recurrent cholesterol embolization. One month after surgery the patient died from a sudden neurological coma. Cholesterol crystal embolization appears to be a contra-indication to heart surgery, even in a strongly symptomatic patient, when the spontaneous course of the existing cardiac disease is not life-threatening in the short term.

Acute postoperative block of mechanical prostheses: incidence and treatment.

Acute intermittent postoperative block of mechanical prostheses is a rare and life-threatening complication; its incidence and treatment are not well defined. Between January 1975 and June 1991, 2839 mechanical prostheses were implanted using the same technique: mattress suture for mitral valve replacement and simple suture for aortic valve replacement. Prosthetic block occurred in eight patients: four following mitral valve replacement and four after aortic valve replacement. The blocked prosthesis was always a tilting disc valve (five Sorin, two Björk-Shiley and one Medtronic). The event occurred over a time interval of 6-48 h (mean(s.d.) 17.3 (15.6)h). All patients having mitral valve replacement needed emergency prosthetic replacement. In aortic valve replacement, reoperation was necessary in two patients; the disc block disappeared in the others. All patients are alive with a follow-up ranging between 3 and 168 (mean 32.5) months. No structural failure was found in explanted prostheses leading to a diagnosis of extrinsic block. The overall incidence of this complication was 0.28% (eight of 2839); 0.24% (four of 1645) for mitral valve replacement and 0.33% (four of 1194) for aortic valve replacement respectively (n.s.). It was exclusively related to tilting disc valves (0.44%; eight of 1830) versus ball and bileaflets valve (0 of 1009). In mitral valve replacement reoperation on patients is mandatory; in aortic valve replacement patients the left ventricular pressure itself can overcome the prosthetic block. Attention should be paid to valve excision and suture techniques as tilting disc prostheses are more vulnerable to extrinsic block. Furthermore, their use is contraindicated in redo operations and mitral valve replacement with total or partial preservation of mitral apparatus.

Effects of alpha-methyl-para-tyrosine on monoamine levels in the Japanese quail: sex differences and testosterone effects.

Experiments were performed to obtain more information on the regulation by steroids of catecholaminergic systems in the brain of Japanese quail. Dose-response and time-response experiments were first performed to determine optimal conditions for measuring turnover in the quail brain. The norepinephrine and dopamine turnover were then estimated in microdissected brain nuclei of birds that were either sexually mature or gonadectomized or gonadectomized and treated with testosterone. Two major facts that bear direct relationship with the control of masculine reproductive behavior were demonstrated. On one hand, the dopamine turnover in the medial preoptic nucleus, a sexually dimorphic brain structure which is critically implicated in the control of copulatory behavior was much higher in male than in female quail irrespective of the hormonal condition of the birds. On the other hand, norepinephrine concentrations appeared to be higher in several nuclei of the female brain by comparison with males. These sex differences might represent part of the causal factors that underlie the sex dimorphism in reproductive behavior in quail.

Testosterone effects on staining density and autoradiographic investigations of the alpha 2-adrenergic receptor in the medial preoptic nucleus of the Japanese quail: relationship to the activation of reproductive behavior.

The effects of gonadectomy combined or not with testosterone (T) therapy on the sexual behavior, cloacal gland area, staining density and alpha 2-adrenergic receptors in the medial preoptic nucleus (POM) were studied in male and female Japanese quail. In castrated males, T increased the cloacal gland size and activated copulatory behavior. In agreement with previous reports, these effects were sexually differentiated: under the influence of T, cloacal gland growth was smaller and this treatment did not activate masculine sexual behavior in females. The optical density of the medial preoptic nucleus stained with thionein blue (Nissl stain) was decreased by castration and increased by T in both males and females. This suggests that T has a profound effect on the synthesis of proteins in the POM and, since POM is a critical site in the activation by T of masculine sexual behavior, these induced proteins are, in all probability, a part of the causal chain of biochemical events giving rise to copulatory behavior. The treatment with T had, by contrast, no clear effect on the number of binding sites and on the affinity of the alpha 2-adrenergic receptors in the POM. Therefore, if the noradrenergic transmission is involved in the induction by T of copulatory behavior, it is probably acting either through the alteration of another adrenergic receptor subtype or through the modulation of the baseline levels or turnover of the transmitter itself.

Effects of testosterone on a selected neuronal population within the preoptic sexually dimorphic nucleus of the Japanese quail.

The effects of testosterone on the volume and cytoarchitecture of the sexually dimorphic nucleus of the preoptic area (POM) were investigated in male and female Japanese quail. It was confirmed that castration decreases the POM volume in males and that, in gonadectomized birds of both sexes, testosterone increases this volume to values similar to those observed in intact sexually mature males. This suggests that the sex difference in POM volume results from a differential activation by T so that this brain morphological characteristic is not truly differentiated in the organizational sense. This conclusion was extended here by demonstrating that males exposed to a photoperiod simulating long days and that are known to have high plasma levels of testosterone have a larger POM than short-day males that have inactive testes. Detailed morphometric studies of POM neurons revealed a structural heterogeneity within the nucleus. A population of large neurons (cross-sectional area larger than 70-80 microns2) was well represented in the dorsolateral but was almost absent in the medial part of POM. This lateral population of neurons was sensitive to variations of testosterone levels in males but not in females. The cross-sectional area, diameter, and perimeter of the dorsolateral neurons were significantly increased in males exposed to high testosterone levels (intact birds exposed to long days or castrated birds treated with the steroid). These changes were not observed in the medial part of the nucleus. Interestingly, the size of the dorsolateral neurons was not affected by testosterone treatments in females. These results suggest that the swelling of neurons in the lateral POM of males might be responsible for the increase in total volume of the nucleus, which is observed in physiological situations associated with a high testosteronemia. In addition, the sensitivity to testosterone of the dorsolateral neurons in the POM appears to be sexually differentiated. This differential response to testosterone might represent a truly dimorphic feature in the organizational sense and additional studies manipulating the early steroid environment should be performed to test this possibility.

[Prosthetic valve endocarditis]. / Endocardite su protesi valvolare.

The Authors report their experience of the surgical treatment of cardiac prosthetic endocarditis. Between September 1974 and December 1988, 2,796 cardiac prostheses were implanted. An endocarditis in the follow-up of 23 patients involving 27 prostheses was diagnosed. The operative mortality was high in patients with mitral prosthetic endocarditis; in patients with infected aortic prosthesis operative mortality was low, but there was a high incidence of recurrence. The Authors emphasize the difficulty of diagnosis and the importance of the surgical treatment for eradication of the infection and for resolution of the haemodynamic defect.

[Etiology and incidence of pure mitral insufficiency: a morphological study of 926 native valves]. / Eziologia ed incidenza dell'insufficienza mitralica pura: studio morfologico su 926 valvole native.

From July 1981 to October 1988, 1597 native valves, 926 (58%) mitral and 671 (42%) aortic, were excised. The gross and histological features of all valves were studied using routine histochemical, immunohistochemical and electron microscopy techniques. As far as mitral valve is concerned the lesions were: stenosis 263 (28.6%), stenosis + incompetence 537 (57.8%) and incompetence 126 (13.6%). Our study was limited to the valves of patients undergoing mitral valve replacement because of pure incompetence. The pathological alterations of the valves were: floppy mitral valve (FMV) 59 (46.8%), rheumatic disease (RD) 50 (39.6%), infective endocarditis (IE) 13 (10.3%), papillary muscles ischemic disease (PMID) 4 (3.1%). In the FMV group the associated lesions were: aortic valve incompetence due to floppy aortic valve and noninflammatory aortic root disease (9-15.2%), tricuspid valve incompetence (4-7.8%) and atrial septal defect (7-13.7%). The commonest complication in this group was rupture of chordae tendineae requiring urgent surgery. In the RD group there was a high incidence of active rheumatism, valvulitis and papillary muscles myocarditis (37-74%) despite the laboratory data were within normal ranges. In the IE group there was an associated aortic endocarditis in 7 patients (53.8%). The FMV was the commonest cause of pure incompetence in patients who had mitral valve replacement. Rheumatic pure mitral incompetence was always associated in our experience to signs of active rheumatic disease.

[Intermediate echocardiographic follow-up of a new model of pericardial prosthesis (Pericarbon)]. / Controllo ecocardiografico a medio termine di un nuovo modello di protesi pericardica (Pericarbon).

The paper deals with the echocardiographic medium-term follow-up of 11 patients fitted with a Sorin Pericarbon bioprosthesis. Four hundred and ninety-seven biological prostheses were implanted during the period January 1975 to December 1988, of which 22 (4.42%) were Pericarbon. The first 11 patients (mean age 55.3 years) who underwent isolated mitral or aortic valve replacement were included in the study. In 5 patients the bioprosthesis was implanted in mitral site, and in 6 in aortic. Post-operative 2D-Doppler echocardiographic tests revealed good hemodynamic performance indices, even in small calibre vessels, and the absence of early malfunctions. Although the number of patients studied is small, the absence of early malfunctions and the technical innovations of the bioprosthesis make it preferable to other pericardiac prostheses.

Results of tricuspid valve replacement for nonrheumatic and noninfective disease.

Because of the rarity of isolated, nonrheumatic, noninfective tricuspid valvular disease, the long-term results of treatment by tricuspid valve replacement are uncertain. From June 1967 to April 1986, we implanted 23 biological or mechanical tricuspid valve prostheses in 20 patients for nonrheumatic, noninfective endocarditis. All cases were followed from 1 to 20 years after the procedure, for a total of 215.08 patient-years. There were 2 hospital deaths and 3 late deaths. Actuarial analysis indicated a mortality rate of 1.39% + 1.6% per year. Late morbidity included 3 episodes of prosthetic thrombosis in 2 patients, arrhythmias in 5 patients, and recurrent spontaneous abortions in 1 patient. New York Heart Association Functional Class improved in all survivors. We conclude that tricuspid valve replacement, especially when a bioprosthesis is used, can be performed with a low operative risk and good long-term results in patients who have nonrheumatic, noninfective, valvular disease.

Post infarction ventricular septal defect. Review of 41 surgical cases.

Forty-one patients with ventricular septal rupture after myocardial infarction were operated over about a 4-year period. The "early" group included 17 patients operated upon within the first 24 hours and 13 of them died. A total of 29 patients were operated within the first week and 21 died. The other 12 were operated after the first week since the diagnosis was made and 11 (92%) survived. The most relevant risk factors were: cardiogenic shock, hypertension and diabetes. The initial management was based on digitalis, diuretics, inotropes (dopamine, dobutamine) and the intra-aortic balloon pump. There was no significant difference in mortality between those patients with associated procedures and those without them, except in those cases of coronary grafts with infartectomy, whose mortality was higher. Early surgical repair of ventricular septal rupture implies a very high mortality (72%), which is even worse when the operation is performed within the first 24 hours (76%).