Glycosaminoglycan levels and structure in a mucopolysaccharidosis IIIA mice and the effect of a highly secreted sulfamidase engineered to cross the blood-brain barrier.

Mucopolysaccharidosis type IIIA (MPS IIIA, Sanfilippo A) is a neurodegenerative lysosomal storage disorder caused by the deficiency of sulphamidase enzyme (SGSH) leading to accumulation of heparan sulfate (HS). We quantitatively and structurally characterize primary stored HS and other glycosaminoglycans (GAGs) possibly accumulated through a secondary storage in brain, liver, kidney and lung of MPS IIIA mouse model. This analysis was also performed in MPS IIIA mice upon the intravenous treatment with an engineered human sulphamidase (chimeric hSGSH) capable to increase its secretion from the liver and to cross the blood-brain barrier. MPS IIIA animals showed a huge accumulation of HS, from ~15 up to ~24-times higher than wild type and also of hyaluronic acid (HA) (from 2.5 up to ~5.0-times more) and chondroitin sulfate (CS)/dermatan sulfate (DS) (from ~2 up to ~5-times more) in all studied organs. We also observed a significant increase in the overall HS charge density and in particular of 2-O-sulfation in MPS IIIA mice organs. 8 months after a systemic treatment with an engineered SGSH, the enzyme was highly efficient in the reduction of all accumulated GAGs in liver, brain and lung up to values of wild type mice. On the contrary, even if reduced, GAGs levels still remained significantly elevated in kidney. Overall data obtained by this detailed analysis of GAGs in the different organs of affected and treated animals with chimeric hSGSH may have implications for the evaluation of an effective therapeutic option of MPS IIIA and for the reduction of related neuropathology.

Mental retardation in mucopolysaccharidoses correlates with high molecular weight urinary heparan sulphate derived glucosamine.

Mucopolysaccharidoses (MPS) are characterized by mental retardation constantly present in the severe forms of Hurler (MPS I), Hunter (MPS II) and Sanfilippo (MPS III) diseases. On the contrary, mental retardation is absent in Morquio (MPS IV) and Maroteaux-Lamy (MPS VI) diseases and absent or only minimal in the attenuated forms of MPS I, II and III. Considering that MPS patients affected by mental disease accumulate heparan sulfate (HS) due to specific enzymatic defects, we hypothesized a possible correlation between urinary HS-derived glucosamine (GlcN) accumulated in tissues and excreted in biological fluids and mental retardation. 83 healthy subjects were found to excrete HS in the form of fragments due to the activity of catabolic enzymes that are absent or impaired in MPS patients. On the contrary, urinary HS in 44 patients was observed to be composed of high molecular weight polymer and fragments of various lengths depending on MPS types. On this basis we correlated mental retardation with GlcN belonging to high and low molecular weight HS. We demonstrate a positive relationship between the accumulation of high molecular weight HS and mental retardation in MPS severe compared to attenuated forms. This is also supported by the consideration that accumulation of other GAGs different from HS, as in MPS IV and MPS VI, and low molecular weight HS fragments do not impact on central nervous system disease.

MR Brain Screening in ADPKD Patients : To Screen or not to Screen?

BACKGROUND: Adult polycystic kidney disease (ADPKD) still represents a major cause of renal failure and intracranial aneurisms (IA) have a higher prevalence in ADPKD than in the general population. Current guidelines suggest performing brain MRI only in the subjects with a positive familiar history of IAs or subarachnoid hemorrhage (SAH). This is a retrospective case-control analysis to evaluate the usefulness of a MR screening program in ADPKD patients. METHODS: We retrospectively analyzed all ADPKD patients followed in our outpatient clinic between 2016 and 2019 who underwent a brain MRI screening. We evaluated the presence of IAs and others brain abnormalities and compared our results with a non-ADPKD population (n = 300). We performed univariate and multivariate regression analysis to evaluate if general and demographic features, laboratory findings, clinical parameters and genetic test results correlated with IAs or other brain abnormalities presence. RESULTS: Among the patients evaluated 17 out of 156 (13.6%) ADPKD patients had IAs, compared to 16 out of 300 (5.3%) non-ADPKD controls (p < 0.005). Considering ADPKD patients presenting IAs, 12 (70.6%) had no family history for IAs or SAH. Genetic analysis was available for 97 patients: in the sub-population with IAs, 13 (76.5%) presented a PKD1 mutation and none a PKD2 mutation. We found that arachnoid cysts (AC) (p < 0.001) and arterial anatomical variants (p < 0.04) were significantly more frequent in ADPKD patients. CONCLUSION: In our population ADPKD patients showed a higher prevalence of IAs, AC and arterial variants compared to non-ADPKD. Most of the IAs were found in patients presenting a PKD1 mutation. We found a significant number of alterations even in those patients without a family history of IAs or SAH. The practice of submitting only patients with familial IAs or kidney transplantation candidates to MRI scan should be re-evaluated.

Unruptured ventricular septal wall dissection. A case report.

Dissection of the interventricular septum (IVS) is a rare condition, which can uncommonly complicate an acute myocardial infarction (AMI). We describe a case of unruptured IVS dissection observed 16 days after 2 close episodes of AMI. The diagnosis was made by transthoracic echocardiography. An echo-free space within the thickness of IVS, extended from the apex to the mid-portion, for a total length of about 30 mm was evident. The careful examination of the left ventricle did not reveal any discontinuity of the myocardial wall. The stable clinical condition, the absence of flow within the dissection, the demonstration of its favourable evolution during the hospitalisation and the characteristics of the underlying coronary disease (left anterior descending artery occlusion without myocardial viability) led to the decision of avoiding surgery. The predischarge contrast echocardiographic examination (Levovist) showed clearly the border of the infarcted zone and demonstrated an area reduction and echogenicity increase of the neocavitation, with partially organised thrombi. The patient recovered uneventfully and was discharged on medical therapy with a clinical and echocardiographic follow-up program. We believe that for IVS hemorrhagic dissection a nonsurgical option can be proposed; surgery should only be considered for myocardial revascularization when indicated. A close echocardiographic follow-up is mandatory.

Effects of adenosine and defibrotide adjunct to a standard crystalloid cardioplegic solution.

AIM: Adenosine has many actions potentially useful as adjunct to a cardioplegia. Defibrotide was recently shown to have protective effects during cardiac arrest. The aim of this study was to compare these 2 substances to delineate their profile of action in the setting of cardioplegic arrest. METHODS: A Langendorff model for isolated rat hearts was employed: 3 groups of 8 hearts each were used, respectively with plain St. Thomas cardioplegia as control (group C), and the same solution added with adenosine (group A) or defibrotide (group D). The hearts had a baseline perfusion for 30 minutes with Krebs-Henseleit solution at 37 degrees C, cardioplegia administration for 3 minutes, then 30 minutes of ischemia without any perfusion and finally 30 minutes of reperfusion with Krebs-Henseleit solution at 37 degrees C. RESULTS: The time to attain heart arrest was 20% shorter in group A, but this difference did not reach statistical significance (A: 13.6+/-1.5; D: 16.8+/-2.7; C: 17.3+/-2.2 s). The heart rate during reperfusion in group A was almost identical to baseline, while in both group C and D it was significantly lower (A: 101%, D: 93.4%, C: 82.4%, p<0.01).A and D decreased significantly the release of creatine phospokinase compared to group C (p=0.006). Lactate dehydrogenase release was lower in both treatment groups, although statistical significance was not reached. Peak positive dP/dT decreased more in controls during reperfusion (A: -23+/-6%, D: -17+/-5%, C: -31+/-5%, p=ns). Negative dP/dT was significantly worse in controls compared to both treatments (A: -19+/-6%, D: -12+/-5%, C: -34+/-7%, p=0.035). CONCLUSIONS: Both adenosine and defibrotide have protective effects in an isolated model of cardioplegic arrest. Adenosine is significantly more active on heart rate while defibrotide is more active on contractily. Further studies are justified in order to test the combination of these 2 drugs.

The use of COLD-PCR, DHPLC and GeneScanning for the highly sensitive detection of c-KIT somatic mutations in canine mast cell tumours.

The conventional polymerase chain reaction (PCR)/sequencing methods may be poorly suited for the detection of somatic mutations in canine mast cell tumour (MCT) samples owing to limited sensitivity. This study was aimed at establishing novel and more sensitive methods, assessing their limit of detection and comparing their sensitivity with conventional methods.Two different 'driver' somatic mutations of c-KIT, together with the wild-type counterparts, were cloned in plasmids to prepare standard samples with known concentrations of mutated alleles in a background of wild-type alleles; the plasmids standards were assayed using either conventional or novel, highly sensitive technique. Conventional PCR/sequencing showed a sensitivity of 50-20%. Conversely, all the novel methods obtained higher sensitivities allowed reaching as low as 2.5-1.2% of the mutated DNA.The study demonstrates that early conventional methods could likely have underestimated the prevalence of KIT mutations of MCTs, therefore affecting the assessment of their relevance in prognosis and tyrosine kinase inhibitor (TKI) treatment effectiveness.

Impaired telomerase activity in uninfected haematopoietic progenitors in HIV-1-infected patients.

BACKGROUND: Haematopoietic progenitor cells (HPC) of HIV-1-infected patients are severely compromised in their replication and clonogenic capacities, and show an enhanced propensity to apoptosis, despite the lack of productive or latent HIV-1 infection. OBJECTIVE: To investigate telomerase enzyme levels in CD34+ HPC isolated from HIV-1-infected patients, because the absence of telomerase activity has been found to be correlated with a diminished replication potential. METHODS: Telomerase levels were measured by a PCR-based telomeric repeat amplification protocol. CD34+ HPC isolated from the peripheral blood of 11 HIV-1-infected patients were compared with CD34+ HPC isolated from peripheral blood (nine subjects) or bone marrow (six subjects) from 15 healthy donors. Telomerase levels were also studied in normal HPC after exposure to either gp120 or transforming growth factor (TGF)-beta1. RESULTS: CD34+ HPC isolated from either peripheral blood or bone marrow from healthy donors expressed a high level of telomerase activity. On the contrary, CD34+ HPC isolated from HIV-1-seropositive patients did not express any detectable telomerase activity in nine patients, and a clearly reduced enzymatic activity in two patients. Furthermore, telomerase activity in normal CD34+ HPC exposed to recombinant gp120 was significantly reduced, and to a higher extent than in CD34+ HPC exposed to recombinant TGF-beta1. CONCLUSIONS: This is the first study to demonstrate severely impaired telomerase activity in uninfected CD34+ HPC isolated from HIV-1-infected patients. The mechanism underlying this impairment probably involves the interaction of HIV-1 envelope glycoprotein gp120 with the cell membrane. These results may add to our understanding of the pathogenesis of the lesion of the HPC compartment.

Leber's hereditary optic neuropathy: genetic, biochemical, and phosphorus magnetic resonance spectroscopy study in an Italian family.

Three siblings of a family affected with Leber's hereditary optic neuropathy (LHON) showed a mitochondrial DNA mutation at position 11778. The lactate response to a standardized effort was increased in only one case. Muscle biopsies and biochemistry of muscle and platelet mitochondrial enzymes were normal. All patients showed an altered energy metabolism during exercise and during recovery after exercise on phosphorus 31-magnetic resonance spectroscopy (31P-MRS) of muscle. Brain 31P-MRS showed a decreased energy reserve (decreased PCr/Pi ratio) in all patients. 31P-MRS noninvasively demonstrated an altered mitochondrial energy metabolism in muscle and, for the first time, in the brains of LHON patients.

Temperature-dependent coronary reactivity after perfusion with University of Wisconsin solution in the isolated rat heart.

The purpose of this study was to determine the effects of different temperatures of University of Wisconsin solution on the reactivity of the coronary vasculature in retrogradely perfused isolated rat hearts. Hearts were perfused for 30 min at 20 degrees C or single-flush perfused at 12 degrees C and 4 degrees C. To study both endothelium-dependent and direct effects on smooth muscle, vasodilation was induced with 5-hydroxytryptamine (5-HT) and nitroglycerin (GTN). The vasodilatory effects of 5-HT and GTN during basal conditions were completely lost and instead a vasoconstriction was observed after 30-min perfusion at 20 degrees C (5-HT: 23.7 +/- 5% before to -19.2 +/- 8% after perfusion; GTN: 33.7 +/- 5.5% before and -11.9 +/- 6% after perfusion). The same response was observed after single-flush perfusion at 12 degrees C (5-HT: 26.5 +/- 5% and -6.5 +/- 3% and GTN: 35.9 +/- 6% and -11.2 +/- 4% before and after perfusion, respectively). Single-flush perfusion at 4 degrees C did not alter the response to 5-HT and GTN (5-HT: 25.9 +/- 6% and 30.4 +/- 7% and GTN: 45 +/- 5% and 32.7 +/- 7% before and after perfusion, respectively). This study suggests that the coronary reactivity after perfusion with University of Wisconsin solution is dependent of the temperature of the solution and provides good preservation of the coronary vascular function at 4 degrees C, whereas temperatures above 12 degrees C might be detrimental.

New strategies for selection of unrelated bone marrow donors.

An important problem in the selection of unrelated donors for bone marrow transplantation (UD-BMT), is HLA matching, between selected donor and recipient. Serological screening, mixed lymphocyte culture (MLC), and sequence specific oligonucleotide genotyping (PCR-SSO) are the methods commonly used for typing of HLA-genes. These ways to select donor candidates are time-expensive. We set up new applications of the "fingerprinting-PCR" technique, to analyse the polymorphic second exon of DRB, DQB, DQA, DPB of HLA Class II and second exon A, B, C HLA-Class I genes, and to search for identity between patient and serologically selected unrelated donors. In an assessment of the technique, 50 normal samples, and 4 unrelated HLA-A and HLA-B serological matched patient-donor pairs were analysed for HLA polymorphic regions. In 3 of the 4 cases (UD-BMT) at least HLA-DRB mismatched different donor-transplanted patterns were identified. In all cases PCR-SSO analysis was performed as control. Based on our data, we suggest that identification of UD for allogeneic BMT should follow these steps: 1) serological HLA-Class I and II genes screening; 2) HLA-Class II DRB gene PCR fingerprinting; 3) confirmation by SSO analysis in case of fingerprinting identity. 4) HLA-Class II DQA, DQB, DPB PCR fingerprinting. Moreover, confirmation by PCR fingerprinting or protein isoelectrofocusing of HLA-Class I identity is recommended. This "strategy" may contribute to rapid and specific selection of unrelated marrow donors.

Molecular analysis of HLA genes for the selection of unrelated bone marrow donor.

The selection of fully matched unrelated volunteer donors (UVD) in BMT requires a molecular characterization of MHC polymorphism, since most phenotypically HLA-identical donors can be non-identical when analyzed at a genomic level. The present report describes a molecular typing protocol for HLA genes developed for the selection of UVD, and its application to some donor-recipient pairs. The protocol involves three successive steps. Firstly, PCR with sequence-specific primers for HLA-DRB1 and -DQB1 genes is performed to identify the major alleles of the recipient. PCR-fingerprint matching is then introduced for HLA-A, B, C and DRB, DQB and DPB genes to screen prospective donors. Those showing matched fingerprinting patterns are finally submitted to direct sequencing of the DRB1 gene. DPB compatibility is assessed by oligotyping when there are several potential class I and DRB matched donors. This strategy was applied retrospectively to three BMT recipients and their previously selected donors. Three other patients and their 12 prospective donors were submitted to our protocol before BMT. Clinical evaluation of transplant outcomes indicates the primary importance of complete DRB and class I matching, while DQB and DPB compatibility seems to be less critical.

Interplay between methylenetetrahydrofolate reductase gene polymorphism 677C-->T and serum folate levels in determining hyperhomocysteinemia in heart transplant recipients.

BACKGROUND: Homocysteine metabolism is often impaired in heart transplant recipients, and increased total homocysteine plasma levels may constitute a risk factor for the development of heart allograft vascular disease. Although 677C-->T transition in methylenetetrahydrofolate reductase (MTHFR) is associated with increased homocysteine levels in the general population, it is unclear whether MTHFR polymorphism influences homocysteine metabolism after heart transplant. METHODS: Homocysteine, serum folate, renal function, concentrations of cyclosporine and its metabolites, and MTHFR genotype were determined in 57 heart transplant recipients (age, 55 +/- 11 yr; 21% women; time from transplant, 48 +/- 42 months). RESULTS: Forty nine percent of the study population presented with hyperhomocysteinemia. Homocysteine was 17.1 +/- 5.9 micromol/liter, 19.4 +/- 4.9 micromol/liter, and 26.3 +/- 14.2 micromol/liter for genotypes CC, CT, and TT, respectively (p = 0.028, Kruskal-Wallis test). At multivariate analysis, MTHFR genotype was independently associated with homocysteine (p = 0.005). When the study population was divided into 2 groups accordingly to serum folate levels (above/below the median value of 6.1 ng/ml), MTHFR genotype remained a significant predictor of homocysteine only in patients with low serum folate (p = 0.048). CONCLUSIONS: This study demonstrates that hyperhomocysteinemia is frequent in heart transplant recipients and that the 677C-->T transition in the MTHFR gene independently and unfavorably influences homocysteine metabolism in this group of patients. Adequate folate intake may overcome genetic predisposition to hyperhomocysteinemia.

Retinitis pigmentosa, ataxia, and mental retardation associated with mitochondrial DNA mutation in an Italian family.

An Italian pedigree including two sisters and their mother affected by a neuro-ophthalmic disease characterised by retinitis pigmentosa, ataxia, and psychomotor retardation is reported. Molecular analysis of mitochondrial DNA showed the presence of heteroplasmic 8993 point mutation in the subunit 6 of the ATPase gene. The clinical features and genetic findings in this family were comparable with those recently described in an English family. The mitochondrial DNA analysis of the family showed a correlation between the amount of mutated DNA and the disease severity in the probands, and indicated the presence of a threshold amount of mutated genome inducing ophthalmic defects. Moreover, the comparative analysis of blood, hairs, muscle, and urinary tract epithelia of two probands revealed an essentially similar distribution of mutated and wild type mitochondrial genomes. Our results suggest that the 8993 mitochondrial DNA mutation characterises a disease with similar clinical features in different populations.

Edge-to-edge repair of congenital familiar tricuspid regurgitation: case report.

We report a case of edge-to-edge (Alfieri's technique) repair of congenital familiar tricuspid regurgitation in a 49-year-old woman, who had severe tricuspid regurgitation, atrial septal defect with left-to-right shunt, and two stenoses in peripheral branches of the left pulmonary artery, of no clinical relevance. The repair was performed through a longitudinal inferior partial sternotomy. The atrial septal defect was closed by direct suture; the anterior and posterior leaflets of the tricuspid valve were sutured together. The chordae to the prolapsing medial part of the anterior leaflet were shortened by direct suture to the leaflet free edge. Annuloplasty was performed by means of a Carpentier ring. The final step was edge-to-edge approximation of the septal leaflet to the new antero-posterior position with two interrupted stitches. The hemodynamic result was excellent, and the patient eventually returned to full active life.

Replacement of the ascending aorta with composite valve grafts: long term results.

BACKGROUND AND AIMS OF THE STUDY: Long term survival after replacement of the aortic root is improving. The most common cause of late death is progression of disease in the remaining aorta (dissection or atherosclerosis). The purpose of this study was to review our clinical experience with composite graft replacement of the aortic root with special reference to long term results. MATERIALS AND METHODS: One hundred twenty-six patients (mean age: 53 years) with different pathologies of the ascending aorta underwent aortic root replacement with a composite-graft prosthesis over a 12-year period. Twenty-three patients had previously undergone cardiovascular surgery. The surgical technique included resection of the ascending aorta with the aortic valve and end-to-side anastomosis between full-thickness buttons of the aortic wall with the coronary ostia and the graft. One or more associated cardiovascular procedures were performed in 24 cases. Long term follow up to July 1995 is complete. Uni- and multivariate analysis were performed to identify risk-factors for early and late mortality and reoperation. RESULTS: Twenty-three patients died during the first 30 days (18%). Sixteen of them had aortic dissection. The most common cause of early death was heart failure. Twenty-three patients died during the follow up time with heart failure, again, being the most common cause of death. Thirteen late reoperations on the composite-graft or the remaining aorta were performed in 12 patients, six of whom had Marfan's syndrome. The 30-day mortality at reoperation was 30%. CONCLUSIONS: This surgical option offers good long term results with a five-year actuarial survival of 67% or 75% when the 30-day mortality is excluded. Careful follow up of patients with Marfan's syndrome and/or aortic dissection is mandatory to increase the long term survival.

Aortic surgery in patients with marfan syndrome: long-term survival, morbidity and function.

BACKGROUND AND AIM OF THE STUDY: The natural history of patients with Marfan syndrome is depressing, but surgical intervention on the aorta can improve the prognosis. Study results were analyzed with reference to long-term survival, morbidity and function. METHODS: Seventy-four Marfan patients (51 males, 23 females; mean age 41+/-14 years), underwent first-time aortic surgery between 1977 and 1998. Follow up information regarding mortality, morbidity and functional status was obtained from patient records and by questionnaire. The mean follow up was 5 years (range: 0-19 years). Forty-seven patients (64%) had a dissection, 27 (36%) an aneurysm, and 45 (61%) patients underwent emergency operations (<4 h from arrival at hospital). In 72 patients (97%) the disease affected the ascending aorta, and implantation of a composite graft was the most frequent operation. RESULTS: Overall 30-day mortality was 12% (3% in elective cases, 18% in emergency cases, p <0.05). Emergency operations and surgery extended to the aortic arch were risk factors for early mortality. Overall actuarial survival was 63.4+/-8% at 10 years. Age was the only risk factor for late mortality. Seventeen patients were reoperated on due to pathologies of the remaining aorta (n = 12), pseudoaneurysms (n = 4) and aortic valve endocarditis (n = 1). A total of five patients had endocarditis; one patient with a homograft required surgery, and medical treatment was successful in the other four patients. Five patients had neurological thromboembolic episodes without permanent damage, and six had minor bleeding complications. Freedom from early and late mortality, reoperation on the aorta and major cardiovascular events (endocarditis episodes, thromboembolic/hemorrhagic strokes and other major bleeding/embolic episodes) was 33.3 +/- 8.1% at 10 years. At follow up, 98% of patients were in NYHA functional class I or II, and 80% were working. CONCLUSION: Elective aortic surgery in Marfan patients can be performed with good results. Close follow up of patients undergoing surgery is important. The long-term functional status of surviving patients is satisfactory.

Intrathoracic extrapulmonary hemangiopericytoma. Late local recurrence after radical extirpation of a large tumor.

A 39-year-old woman was operated upon for an extremely large hemangiopericytoma located in the right hemithorax. During intensive follow-up a local recurrence was observed 8 years after the radical extirpation of the well-encapsulated tumor, histologically assessed as generally benign. This and other observations give reason to suspect that the well-recognised puzzling clinical behavior of this rare tumor is a result of a potential pathological capacity of the abnormally vascularised fatty connective tissue through which the tumor is connected to the body. This tissue, if not radically extirpable, must be completely destroyed in some way during or after the operation in order to prevent recurrence.

Glucose-insulin-potassium (GIK) prevents derangement of myocardial metabolism in brain-dead pigs.

Brain death is associated with neuroendocrine changes resulting in reduced myocardial glycogen content. The purpose of this study was to investigate the effects of glucose-insulin-potassium (GIK), on myocardial metabolism in brain-dead pigs. Sixteen brain-dead pigs were given GIK infusion (n = 8), or Ringer solution (n = 8). At end-point (7 h post brain death) arterial concentrations and myocardial arteriovenous (a-v) concentration differences of glucose, lactate and free fatty acids (FFA) were assessed, and myocardial biopsy specimens were taken from the right atrium and left ventricle. Biopsies were also taken from five normal pigs. Myocardial glycogen content in the GIK group was significantly higher compared to the control group, but comparable to the non-brain-dead animals. There was a higher and significant myocardial uptake of glucose and lactate in the GIK group compared to the controls. Plasma levels of FFA were significantly lower in the GIK group, and the myocardial uptake of FFA was 5 times higher in the control group compared to the GIK group. There were no significant differences in hemodynamic variables among the groups. In conclusion, intravenous supply of GIK to brain-dead pigs results in increased myocardial glycogen content and seems to prevent abnormal myocardial metabolism, which may have clinical implications for the myocardial protection of donor hearts.

Different results of cardiac transplantation in patients with ischemic and dilated cardiomyopathy.

We retrospectively analyzed 275 consecutive transplanted patients, dividing them into group A (128 patients) affected by ischemic cardiomyopathy and group B (147 patients) affected by dilated cardiomyopathy. The difference in demographic, clinical and hemodynamic preoperative and postoperative data between the groups was studied; group A patients presented at transplantation with a less compromised hemodynamic picture, requiring inotrope infusion and mechanical assistance less frequently. The influence of etiology on early postoperative complications was also analyzed: group A patients needed postoperative mechanical assistance, inotrope, infusion and prolonged mechanical ventilation more often, therefore requiring a longer stay in the intensive care unit (ICU). Hospital mortality was twice as high in group A. The older age of group A patients per se did not influence these results significantly. The long-term follow-up was then studied with particular attention to parenchymal functions, hemodynamics, coronary artery disease, metabolic and surgical complications, and survival. The complication rate was higher in group A, with more severe hypertension and higher cholesterol levels at 1 year, a higher prevalence of accelerated coronary artery disease (CAD) and a more frequent onset of insulin-dependent diabetes. Surgical and vascular complications were also more frequent. The final result was a better 5-year actuarial survival rate for group B patients. Donor and recipient ages at the time of transplant did not influence this result. We conclude that ischemic patients, even if they are transplanted in better condition and operated more electively, have a more critical early and long-term postoperative course and a worse survival rate. These findings are not explained by advanced age, but could be due to the impact of atherosclerosis and metabolic impairments associated with ischemic disease.

Determination of dexamethasone and two excipients (creatinine and propylparaben) in injections by using UV-spectroscopy and multivariate calibrations.

The use of multivariate spectrophotometric calibration for the simultaneous determination of dexamethasone and two typical excipients (creatinine and propylparaben) in injections is presented. The resolution of the three-component mixture in a matrix of excipients has been accomplished by using partial least-squares (PLS-1). Notwithstanding the elevated degree of spectral overlap, they have been rapidly and simultaneously determined with high accuracy and precision (comparable to the HPLC pharmacopeial method), with no interference, and without resorting to extraction procedures using non-aqueous solvents. A simple and fast method for wavelength selection in the calibration step is used, based on the minimisation of the predicted error sum of squares (PRESS) calculated as a function of a moving spectral window.