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Scoring systems used in meningococcal disease have been developed and validated to predict death or severity of illness in cohorts of patients, usually in the setting of intensive care. When using these scores, it is important to remember that any individual's score is only of limited value in prognosticating about that individual patient and can be misleading (1). The accuracy of any score is determined by how well its estimated pattern of mortality compares with that observed in the score's developmental cohort, rather than in individual patients. Scores cannot be considered interchangeable; different scores, comprised of different sets of variables to arrive at the probability of mortality, may arrive at the same overall aggregate risk of mortality in a population of patients with meningococcal disease, despite individual estimates within this cohort of patients differing widely between scores. The ability of a score to predict death for patients who die and survival for those that live is best-described by the area under the receiver operator characteristic (ROC) curve (2). This curve is a plot of sensitivity versus "(1 -specificity)", i.e., the true-positive to false-positive fractions, at different decision thresholds. The greater the discriminative ability of a test, the closer the area under the curve comes towards 1.0, where the true-positive fraction is 1.0 or 100% (perfect specificity) and the false-positive fraction is 0 (perfect sensitivity). No score, however, has sufficient accuracy for individual prognostication and the use of scores in this way is inappropriate for clinical practice or research (3).

The role of iron-dependent oxidative metabolism in protecting the oxidable substrates contained in mature adipocytes is still unclear. Because differentiation increases ferritin formation in several cell types, thereby leading to an accumulation of H-rich isoferritins, we investigated whether differentiation affects iron metabolism in 3T3-L1 pre-adipocytes. To this aim, we evaluated the expression of the genes coding for the H and L ferritin subunits and for cytoplasmic iron regulatory protein (IRP) during the differentiation of 3T3-L1 cells in adipocytes induced by the addition of isobutylmethylxanthine, insulin, and dexamethasone. Differentiation enhanced ferritin formation and caused overexpression of the H subunit, thus altering the H/L subunit ratio. Northern blot analysis showed increased levels of H subunit mRNA. A gel retardation assay of cytoplasmic extract from differentiated cells, using an iron-responsive element as a probe, revealed enhanced an RNA binding capacity of IRP1, which correlated with the increase of IRP1 mRNA. The observed correlation between differentiation and iron metabolism in adipocytes suggests that an accumulation of H-rich isoferritin may limit the toxicity of iron in adipose tissue, thus exerting an antioxidant function.

We investigated the effect of oxalomalate (OMA, alpha-hydroxy-beta-oxalosuccinic acid), a competitive inhibitor of aconitase, on the RNA-binding activity of the iron-regulatory proteins (IRP1 and IRP2) that control the post-transcriptional expression of various proteins involved in iron metabolism. The RNA-binding activity of IRP was evaluated by electrophoretic mobility-shift assay of cell lysates from 3T3-L1 mouse fibroblasts, SH-SY5Y human cells and mouse livers incubated in vitro with OMA, with and without 2-mercaptoethanol (2-ME). Analogous experiments were performed in vivo by prolonged incubation (72 h) of 3T3-L1 cells with OMA, and by injecting young mice with equimolar concentrations of oxaloacetate and glyoxylate, which are the precursors of OMA synthesis. OMA remarkably decreased the binding activity of IRP1 and, when present, of IRP2, in all samples analysed. In addition, the recovery of IRP1 by 2-ME in the presence of OMA was constantly lower versus control values. These findings suggest that the severe decrease in IRP1 RNA-binding activity depends on: (i) linking of OMA to the active site of aconitase, which prevents the switch to IRP1 and explains resistance to the reducing agents, and (ii) possible interaction of OMA with some functional amino acid residues in IRP that are responsible for binding to the specific mRNA sequences involved in the regulation of iron metabolism.

The behaviour of l-serine in strongly alkaline solution was studied at 25 degrees C and in 3.00 mol/l NaClO(4), as a constant ionic medium, to obtain quantitative information about the eventual dissociation of its alcoholic group. A spectrophotometric method was employed to measure the free concentration of hydrogen ions. Two indicators, methyl thymol blue and eriochrome blue type R, were used. Their values as protonation constants and absorbance coefficients were determined in advance. The method here proposed has been validated beforehand by applying it to d-mannite and glycerine and by comparing results so obtained with those previously provided by literature. The investigation showed weak acid properties of the -OH of serine and its dissociation constant was determined. Polynuclear species or further dissociation were not observed.

The behaviour of taurine as a ligand (L) towards silver(I) and cadmium(II) was studied at 25 degrees C and in 1 mol dm(-3) NaClO(4), as a constant ionic medium. Experimental data, obtained for both cations from electromotive force measurements performed by using silver and cadmium amalgam and glass electrodes, were explained by assuming the formation of the AgL, AgL(2), CdL, and CdL(2) complexes. The taurine protonation constant and stability constants of the above complexes were determined. The cadmium(II)-taurine system was investigated by determining the free concentration of taurine from the Ag electrode potential and the knowledge of equilibria existing between silver(I) and taurine. Experimental data obtained from this approach were explained by assuming the presence of the above species with very close stability constant values. The success of this method supports the possibility of using the Ag/Ag-taurine, taurine electrode to measure the free concentration of taurine in its solutions.

The ability of cysteine to form complexes with cadmium(II) in aqueous solutions has been investigated at 25 degrees C and in constant ionic medium NaCl at two different concentrations, 1.00 and 3.00 mol l(-1). The presence of chloride ions was necessary to avoid the precipitation of cadmium(II). Two kinds of measurements were carried out. The electromotive force of galvanic cells containing glass and cadmium amalgam electrodes was measured as a function of cadmium and hydrogen ion concentrations in acid or moderately alkaline solutions in order to obtain the free concentration of cadmium(II) and hydrogen ions. The experimental data obtained in 1.00 mol l(-1) NaCl were explained by assuming the presence of CdHL and CdH(2)L(2), while those obtained in 3.00 mol l(-1) NaCl were accounted for with the formation of CdHL, CdH(2)L(2), CdH(3)L(3) and CdH(2)L(3). Moreover, polarographic measurements were carried out under the same experimental conditions but in alkaline solutions, and the formation of CdL(2) and CdL(3) was assumed from the shift of E(1/2) of cadmium(II) with an excess of cysteine. The stability constants of the assumed species were determined. Protonation constants of cysteine in 1.00 and 3.00 mol l(-1) NaCl have been also determined. A comparison with the behaviour of serine and alpha-aminopropanoate towards cadmium(II) is proposed.

Bileaflet cardiac prostheses (St. Jude, CarboMedics, Duromedics, Bicarbon, Jyros) have shown a low incidence of complications and good haemodynamic performance. In the last twelve years, 783 bileaflet prostheses were implanted in 690 patients at our Institution. The population of our study comprises 591 bileaflet prostheses (418 CarboMedics, 124 St. Jude, 49 Bicarbon) implanted in the mitral (MVR) (n = 305) or aortic (AVR), (n = 286) position. The follow-up study evaluated 292 male and 295 female patients with age ranging from 13 and 79 years (mean 50.4 +/- 14.7 years). Hospital mortality was 6.6%. Follow-up was 97% complete, with 1822 +/- 33 patient/years and a mean follow-up of 37 months (range 1 to 144 months). Twelve years actuarial freedom from complication according to prosthetic site were calculated as follows (linearized rates in parentheses): late mortality AVR 97.6% +/- 0.6% (2.3%), MVR 96% +/- 0.5% (2.1%); thrombosis AVR 100%, MVR 96% +/- 0.9% (0.8%); embolism AVR 97% +/- 0.5% (1.5%), MVR 96.6% +/- 0.7% (1.8%). Global freedom from anticoagulant-related haemorrhage was 95% +/- 1.2% (2.3%) and 94.5% +/- 0.7% (2.2%) following AVR, 94 +/- 0.6% (2.1%) following MVR. The difference of the haemorrhagic risk for prosthetic site was not significant (p > 0.05). Functional improvement was confirmed by the low postoperative NYHA functional class. According to our results, cumulative experience with bileaflet valves has shown very good long-term results in term of low rate of complication, long-term survival and quality of life.

A poisoning from a Veratrum album infusion mistaken for Gentiana lutea is described. Confusion between these two plants can easily occur because they are very similar, although flowers and disposition of leaves allow their botanic determinat: V. album leaves are alternate and flowers are white, while G. lutea leaves are opposite and flowers yellow. The poisoning involves gastrointestinal (pyrosis, vomiting) and cardiocirculatory systems (bradyarrhy-thmias, A-V dissociation, vasodilatation) Atropine is the drug of choice.

Submitral left ventricular aneurysm most commonly occurs among the black population. Nevertheless, this lesion has been described among whites. We report 2 cases of submitral left ventricular aneurysm that we treated successfully by surgery. Case 1 is that of a 52-year-old Brazilian black man with a submitral left aneurysm and mitral incompetence. Case 2 is that of a 25-year-old white man with a history of recurrent stroke; his echocardiographic study showed a small submitral left ventricular aneurysm. Due to the growing incidence of submitral left ventricular aneurysm among the white population, we emphasize the importance of a targeted echocardiographic study in all patients with a history of embolic episodes in the absence of apparent risk factors for embolism.

We report the implantation of a fresh, stentless pulmonary homograft in the mitral position as an attempt to treat the 2nd recurrence of prosthetic endocarditis in a 66-year-old man. The postoperative course was uneventful; early postoperative transesophageal echocardiography showed a competent valve with a gradient of 4.2 mmHg. Fifteen months postoperatively, transthoracic echocardiography showed a good functioning homograft with a competent valve and no recurrence of endocarditis.

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.

An acute obstruction is a life-threatening complication of mechanical valve prostheses, and is caused by the formation of fresh clot or fibrous tissue overgrowth, or both. Accurate selection of the most appropriate treatment for a particular patient is mandatory. From January 1991 to July 1992, 28 cases of prosthetic thrombosis were managed. Twenty patients underwent surgical treatment, with one operative death, and 8 patients were treated with thrombolysis using recombinant tissue-type plasminogen activator (rt-PA). The criteria for using thrombolysis were (1) the recent onset of symptoms, (2) transesophageal echocardiographic evidence of clots on the valve or cardiac chambers, and (3) preserved disc excursions. All patients who underwent thrombolysis had mechanical valves (two bileaflets, four tilting discs, and two ball valves); seven valves were in the mitral position and one was in the aortic. Symptoms of obstruction consisted of cardiac failure in 6 cases or thromboembolism in 5, or both. The mean interval between the onset of symptoms and the initiation of thrombolysis was 81 +/- 65 hours. After infusion of the rt-PA, normal valve function was restored in all patients, as documented by transesophageal echocardiography. No deaths or neurologic complications occurred; there was one episode of minor peripheral embolism. Thrombolysis using rt-PA may be the appropriate treatment in patients with primary thrombosis of mechanical valves, thereby avoiding the operation-related risks.

The authors describe a case of a female obese patient with cushingoid habitus who was not suffering from Cushing's syndrome or disease but from empty sella syndrome. The authors emphasize the importance of a systematic search for possible causes of obesity, especially if it joins with a particular habitus.

A size 3 laryngeal mask was used in 20 patients who underwent elective general surgery. It consists of a silicon tube attached to mask which must be inserted into the hypopharynx and then inflated. No curarisation nor laryngoscopy is needed. Operations were performed in assisted or spontaneous ventilation, with good airway patency and absence of coughing, secretions and sore throat. In 2 cases introduction of the mask failed. Technique, advantages and problems related to its use are described.

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.

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.

In 10 patients who required extracorporeal circulation (ECC) during surgery, we studied the damage induced by surgery to the pulmonary surfactant and the effectiveness of ambroxol in preventing changes in the phospholipid pool. There were 5 control patients and 5 patients who were given 1 g/day of ambroxol on the 4 days prior to and the 4 days after surgery. To follow changes in phospholipid concentrations, bronchoalveolar lavage (BAL) was performed before surgery and 24 h and 8 days after ECC. Phospholipids were assayed in the BAL liquid by two-dimensional thin-layer chromatography. There were marked decreases in total phosphorus and quantitative alterations of individual phospholipid species in the surfactant of the control group, but not in the patients treated with ambroxol.

In this work a case of splenic Hodgkin's disease is reported. It was diagnosed only by a second exploratory laparotomy. There was no involvement of lymph nodes, other organs or systems. Hodgkin's disease was histologically associated with sarcoid-like granulomas and the significance of this association is discussed. In addition to splenectomy, this patient was treated with chemotherapy.

The surgical treatment of 6 patients affected by right cardiac tumors is reported. Three of them showed a right atrial myxoma, 1 metastases from an occult embryonal carcinoma and 1 a leiomyosarcoma of the pulmonary artery. While clinical diagnosis was not reliable, the echocardiographic examination was able to assess the site of the tumor, supplying useful information for the anatomy and surgery in 5 cases out of 6; in one case, the diagnosis was reached intraoperatively. All the patients survived the surgical treatment: while those with atrial myxoma recovered completely, the others with malignant tumors died from metastases 5 to 10 months postoperatively. The importance of early diagnosis is stressed together with the role of surgery, which permits the recovery of cases with benign tumors and a longer survival of cases with malignant tumors.

A clinical and hemodynamic study of a case of polysplenia, with typical left bilateral symmetry, anomalies of systemic venous drainage and defect of the endocardial cushions. A brief revision of the literature is given and the embriological and clinical concept of the left bilateral symmetry is discussed.

In order to evaluate the influence of the profile of mitral prostheses on the outflow tract of the left ventricle, 99 patients underwent M-Mode echocardiography before and after surgery. In 67 cases high profile mitral prostheses had been implanted (48 mechanical and 19 biological); in 32 cases low profile mitral prostheses had been implanted (22 mechanical, 10 biological). Echocardiography showed that the implantation of high profile mitral prostheses did not induce changes of left ventricular diastolic and systolic dimensions ( EDDLV and ESDLV ) while induced significant reduction of left ventricular outflow tract (LVOT) dimension and LVOT/ EDDLV index with subsequent changes in transaortic flow. On the other hand, low profile prostheses did not induce significant changes of left ventricular dimensions, LVOT and LVOT/ EDDLV index. Finally, low profile biological mitral valve prostheses ( Liotta type) induced a significant increase of post-operative dimension of LVOT and LVOT/ EDDLV index. Authors conclude: that the implantation of high profile mitral prostheses changes LVOT dimension and transaortic flow and, that M-Mode echocardiography is a reliable technique to point out these changes.

A ten-year experience with reoperations for failure of cardiac bioprostheses is reported. 362 patients were operated for valve replacement with 412 bioprostheses. There were 35 (9.64%) reoperations for valve failure. Mean time between operation and reoperation was of 64.4 months. Operative mortality was 14.28%: 3 patients died for cardiac and 2 for extra-cardiac causes. Long-term mortality after reoperation was 6.25%. Morphological examination of the explanted bioprostheses confirmed the cause of bioprosthetic valve failure, due to calcific degeneration in 88.88% of case, to post-endocarditic rupture in 5.55% and to prosthetic thrombosis in 2.77%. The importance of timing reoperation is stressed in order to reduce the operative mortality. The conditions suitable for implantation of bioprostheses are listed.

To determine the influence of zinc intake on copper excretion and retention, nine men consumed diets containing 2.6 mg of copper/day and 1.8, 4.0, 6.0, 8.0, 18.5 or 20.7 mg of zinc/day for one- or two-week periods in a 63-day study. Copper and zinc in the diet and copper in plasma were determined weekly; fecal copper was determined daily and averaged within each week. The weekly mean (+/-SEM) plasma copper concentrations (81 +/- 3.3 to 100 +/- 5.8 micrograms/dl) remained within the normal range throughout the study. Fecal copper and apparent copper retention were influenced by the level of dietary zinc and the duration it was fed. When 18.5 mg of zinc/day was fed for two consecutive weeks following a lower zinc intake, fecal copper was elevated and apparent copper retention was reduced after a one-week lag. Thus, an intake of zinc only 3.5 mg/day above the RDA for men reduced apparent retention of copper at an intake of 2.6 mg/day.

Two successful cases of mitral valve replacement with cardiopulmonary by-pass and myocardial protection are reported. Postoperative anticoagulation was obtained with oral anticoagulants. The patients delivered two healthy newborns. The report suggests that an open-heart operation can be performed in pregnant women with an acceptable risk for the mother and the fetus.

A clinico-pathologic study was performed in 25 patients undergoing aortic valve replacement because of regurgitation, caused by myxoid degeneration of the valve leaflets. Associated cardiac anomalies were floppy mitral valve (2 cases), floppy mitral valve and idiopathic hypertrophic subaortic stenosis (1), left atrial myxoma (1), and aortic coarctation at the isthmus (1). Three patients died (2 immediately and 1 on the 30th postoperative day). Pathological studies of the explanted valves showed deformities characterized by redundant thin leaflets which appeared soft and gelatinous. On histologic examination the fibrous layer of the leaflets was seen to be infiltrated by myxomatous tissue. Echocardiography showed the aortic root to be dilated in 13 patients and normal in the others. In those with normal aortic root, the histological examination of aortic wall disclosed minimal cystic medial necrosis in two cases. In contrast, more severe forms of cystic medial necrosis were evident in all patients having a dilated aortic root. Aortic valve replacement was performed in all cases. It was accompanied by a Bentall procedure (1 case), repair of ascending aorta dissection (2), replacement of the ascending aorta (1), mitral valve replacement (2), mitral valve replacement and apico-ascending aorta conduit (1) and excision of a left atrial myxoma (1). Our experience suggests that prolapse of the aortic valve due to floppy leaflets is a common degenerative disease which is generally associated with noninflammatory aortic root degeneration. This, together with aortic root dilatation, contributes to valve insufficiency. Nevertheless, the disease, when isolated (with normal aortic root), is liable in itself to produce aortic regurgitation. The need for early diagnosis is stressed, so as to be able to perform valve replacement.

The Model 6120 ball valve prosthesis introduced in 1965 is still strongly supported as a mitral valve substitute in many centers around the world. A current reassessment of the performance of this prosthesis is therefore pertinent to current medical practice. In this institution since 1974, 227 Starr-Edwards caged ball valves have been implanted in the mitral position during isolated valve replacement. Two models of caged ball valves were used concurrently: the silastic ball valve in 108 patients (48%) and the composite strut "tract" valve in 119 (52%). Hospital mortality was 7%, and 8-year survival (standard error) was 74 (6%), with 100% follow-up, documenting 752 total patient-years. No late deaths were known to be valve related, and there were no cases of prosthetic thrombosis. The actuarial estimate of patients free from thromboembolism at 8 years was 89 (4%) with a linearized rate of 1.3% per year. At the most recent follow-up, 95% of the patients were in the New York Heart Association (NYHA) Classes I or II. These good results were partly due to an awareness at operation of ventricular outflow tract size requirements and to strict control of postoperative anticoagulation. We conclude that the Starr-Edwards ball valve is the mitral valve of choice in the young patient who is able to take anticoagulation drugs and has a left ventricular outflow tract of satisfactory size.

The mechanical valve produced by Sorin is a modified tilting disc device. Over about a 6-year period, 763 Sorin Prostheses were implanted in 710 patients. No structural failure has been observed. 282 prostheses were implanted in aortic position with the large orifice oriented towards the right coronary sinus. Hospital mortality was 5% (14/282). Actuarial survival at 78 months was 94.68% +/- 1.6%, with a linearized mortality rate of 1.7% pt-years. There were 11 late deaths (9 valve related and 2 non valve-related). The linearized rate of occurrence of embolic events was 0.32 pt-years (2/268). Actuarial survival complication free at 78 months was 90.88% +/- 2.83%. Preop. 19.8% patients were in class II N.Y.H.A, 68.5% in III, 11.7% in IV; postop. 79.3% patients were in class I, 19.5% in II, 1.2% in III. The durability and satisfactory complication-free survival rate indicate the Sorin prosthesis as a fully reliable device for aortic valve replacement.