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The terrestrial soil organic matter (SOM) pool size depends on the balance between SOM formation and stabilization of decomposing plant litter relative to mineralization as CO2. Decomposition and mineralization processes are to large extents mediated by microbial decomposer communities. In addition, labile fractions released by decomposing litter can be stabilized in mineral associations (MAOM). High latitude ecosystems are particularly affected by global warming. Increasing temperatures can stimulate litter decomposition and increase nutrient mineralization, thereby increasing nutrient (e.g. nitrogen) availability for plants allowing higher productivity and subsequent plant organic matter inputs. On the other hand, if warming accelerates SOM decomposition stronger than formation processes it can cause large carbon and nutrient losses.Tracing 13C/15N labelled above-ground litter we aimed to disentangle if soil warming changes the balance between litter derived SOM formation through microbial communities, over particulate organic matter (POM) and MAOM stabilization across a decadal geothermal soil warming gradient (from ambient up to +5 °C) in a grassland in Iceland. In addition, we added three levels of inorganic N to disentangle potential direct warming from indirect (over plant feedbacks) effects of increased warming on SOM dynamics. We found that over the course of two years warming accelerated litter decomposition rates and litter-derived carbon turnover by the microbial community, and we could recover more litter-derived carbon recovered in particulate organic matter (POM) nor MAOM. Nitrogen additions triggered a faster decomposition of structural above-ground litter compounds, but did not influence carbon turnover in different soil fractions. On the other, hand we found that overall the absolute amount of soil carbon decreased in response to warming. We therefore conclude that direct warming not only increased SOM formation, but also decomposition and mineralization processes, and – at least in the studied grassland – plant inputs may not have counterbalanced warming induced losses.

We report a novel, fully-integrated nanophotonic wavelength and displacement sensor based on an electrostatically-actuated double-membrane photonic crystal nanocavity detector with a quantum dot absorption region.

Background. The aim of this study was to assess the prevalence of pericardial effusion in acute myocardial infarction and the different prognosis associated with distinct patterns of pericardial effusion (anechoic/hypoechoic vs hyperechoic effusion). Methods. Five hundred eighty-five consecutive patients admitted to the Coronary Care Unit for acute myocardial infarction were initially considered. Forty of them were excluded due to a technically poor acoustic window. The remaining 545 patients were studied by two-dimensional echocardiography at admission, before discharge (after an average of 9 days in the Coronary Care Unit) and whenever there was an important change in the clinical status (chest pain, lipothymia or syncope, hemodynamic deterioration with systolic blood pressure < 90 mmHg, cardiac arrest). Results. Pericardial effusion was found in 51 patients (9%). Three distinct textural patterns of pericardial effusion were noted on the basis of the echogenic properties: 1) anechoic or hypoechoic pericardial effusion was frequent (30 patients), mild or moderate and generally benign; 2) hyperechoic type 'A' effusion pattern was rare (2 patients) and associated with fever, leukocytosis and pericardial rubs; 3) hyperechoic type 'B' was frequent (19 patients), large and always associated with major complications (all cases cardiac tamponade and/or death). Conclusions. Pericardial effusion is not an uncommon finding in serial echo evaluation of patients with acute myocardial infarction, especially when infarction is anterior, extensive and Q wave. Echocardiographically detected pericardial effusion shows different textural patterns with hypoanechoic effusion more frequent, limited and prognostically benign than hyperechoic effusion larger and often associated with adverse events.

Knowledge of the characteristics of the normal human aorta has been constrained by lack of data on fresh aortic tissue, especially from healthy individuals. In this study, the gene expression and morphological characteristics of the thoracic ascending aorta (AA) of healthy organ donors have been evaluated, with the aim of providing reference data for the analysis of pathological AAs. We analysed by RT-PCR the differential expression of mRNAs coding for myocardin, smoothelin, alpha-smooth muscle actin (alpha-SMA) and the ED-A isoform of fibronectin (ED-A FN) in AA specimens from donors, integrating the results with immunohistochemical analysis of the same targets. Morphological and morphometric characteristics of the AAs were also evaluated. In order to account for possible regional variations in wall structure, the convexity of the aortic profile was compared to the concavity. No differences in gene expression occurred for any of the target genes between the concavity and the convexity of AAs. Immunohistochemistry revealed a different distribution of total FN and of its ED-A isoform in the media and in the intima. Smoothelin is expressed by the majority of cells in the media, with some positive cells also in the intima. Alpha-SMA is expressed in all the tunicae. Immunohistochemistry also revealed in the convexity of 50% of AAs the presence of discrete areas in the subadventital media with altered structure and cell morphology and with altered gene expression, resulting positive for ED-A FN and alpha-SMA, but not for smoothelin, indicating the occurrence of early lesions also in macroscopically healthy AAs.

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.

Recently, the presence of dividing cells was observed in the sections of adult human heart. These cells have been identified as cardiac stem cells, giving rise to the precursors of all cardiac cell lineages, but to the best of our knowledge the isolation of resident stem cells and primitive cells from the adult human heart has not been accomplished before. The aim of our study was the isolation and characterization of primitive cells from adult human heart in the normal and pathological conditions. We used bioptic pieces from normal adult hearts (n=9) and from human hearts explanted due to the ischemic cardiomyopathy (n=12) to obtain the outgrowth of cardiac cells in vitro. The fibroblasts were removed by the depletion during magnetic cell sorting and the primitive cells constituted 10% of the cells in culture. Subsequently, the cells expressing c-kit (CD117) were positively selected by the same method. The progenitor and precursors of all cardiac cell lineages were quantified by immunocytochemistry. Moreover, their apoptosis after induction with H2O2 and proliferation in the normal culture conditions were compared by TdT assay and BrdU incorporation, respectively. While 90% of primitive cells from the normal heart was CD117(+), they constituted only 40% of primitive cells in the pathological hearts. The number of cardiomyocyte progenitors Nkx 2.5(+), α/βMHC(-) among the cells from pathological hearts was 3-fold higher, while the number of precursors CD117(+), α/βMHC(+) did not differ significantly when compared with the cells from normal hearts. Committed to the endothelial cell lineage progenitors Ets-1(+), fVIII(-) and precursors fVIII(+) were 3-fold more abundant in the diseased hearts. The number of smooth muscle cell progenitors GATA6(+), α-SMA(-) and precursors expressing α-SMA did not differ, reflecting their minor role in the cardiac tissue regeneration (smooth muscle cells not being present in the capillaries). The percentage of proliferating CD117(+) cells was 2-fold higher in the pathological hearts, but their level of apoptosis was also 2-fold higher, when compared with the cells from normal hearts. These results suggest that the adult human cardiac primitive cells undergo activation in the chronic pathological conditions and with the augmented progenies generation, they lose the stem cell marker CD117. The increase in the apoptosis rate reflects their increased turnover, which may reduce the number of cells reaching terminal differentiation and allow the progression of heart failure.

To evaluate the long-term results of patients who underwent bladder autoaugmentation (BA) in whom BA was used to treat a neuropathic bladder secondary to myelomeningocele, and who presented with a high-pressure/poorly compliant bladder.Eleven patients (eight girls and three boys, mean age 12.8 years, mean follow-up 6.6 years) were selected who had undergone BA between June 1991 and June 1994. At surgery, the patients had a poorly compliant bladder with a mean leak point volume (LPV) of 94 mL and a mean leak point pressure (LPP) of 58 cmH2O. None of the patients had vesico-ureteric reflux (VUR) at BA; five with grade III or IV VUR had undergone endoscopic correction in a day-surgery procedure using a suburethral collagen injection 1-3 weeks before BA. The patients were evaluated using clinical, urodynamic, radiological and endoscopic assessments. The LPV, LPP and safe bladder capacity (SBC, the cystometric volume at an intravesical pressure of 40 cmH2O) were recorded.At 1 year after surgery the mean LPV was 297 mL; none of the patients had VUR. The most recent mean LPV was 198 mL and the SBC 167 mL. The mean LPP remained stable at 60 cmH2O. At the last follow-up four patients had recurrent uni- or bilateral grade III-V VUR. At endoscopy the 'augmented' bladder portion had a smooth surface, compared with the grossly trabeculated lower half. From this finding all patients on clean intermittent catheterization were treated with oral oxybutynin. Some patients reported slightly less abdominal pain at maximum bladder volume; four needed pads to treat intermittent incontinence. On voiding cysto-urethrography, one patient had an hourglass-shaped bladder. Five patients recently underwent ileocystoplasty because of recurrent urinary tract infection, high-grade VUR and incontinence.These results do not justify the routine use of BA in hypertonic/poorly compliant bladders secondary to myelomeningocele. The mean follow-up of 6.6 years showed that this procedure failed in seven of 11 patients. Further studies might be able to identify subgroups in which this approach may be more appropriate.

Most previous studies on surgery for endocarditis included cases of both prosthetic and native valve endocarditis (NVE), which clearly differ in their course and prognosis.Between February 1979 and July 2000, 199 patients underwent surgical treatment for NVE. The native valve was replaced in 185 patients, and repaired in 14. Correlations between previous heart disease and site of NVE, site and etiology, site and embolism, and etiology and extracardiac infection were analyzed. Viability of echocardiography to identify NVE features was compared with surgical inspection. Risk factors for hospital, late mortality and recurrence were assessed by multivariate analysis, including preoperative, operative and postoperative variables.Streptococci were found in 52 cases (26.1%), mostly spreading from splanchnic (n = 10) and cutaneous (n = 9) infections; Staphylococci were found in 43 cases (21.6%), mostly from cutaneous foci (n = 20). Tricuspid valve endocarditis was due to Staphylococcus sp. in all documented cases (11/15; p0.001), while Streptococcus sp. predominated in the mitral (p = 0.026) position. Echocardiography was reliable in identifying anatomic features of NVE, except for periannular abscess (13 versus 31 found at surgery; p0.001). Hospital mortality was 6% (n = 12): preoperative NYHA class IV (p = 0.034) and emergency surgery (p = 0.001) were significant predictors of mortality. Average follow up was 57.2+/-4.4 months and was 96.3% complete. There were 27 late deaths (15%). Actuarial survival was 75.7% at 10 years and 60.3% at 20 years. Low social status (p = 0.022), diabetes mellitus (p = 0.003), fever at time of surgery (p = 0.041) and persistent postoperative fever (p = 0.0002) were predictors for late mortality. Endocarditis recurred in 28 patients (15.5%), with 74.1% freedom at 10 years and 68.7% at 20 years. Drug abuse (p = 0.001), mitral endocarditis (p = 0.002), positive blood cultures (p = 0.0003), homograft implantation (p = 0.0012) and persistent postoperative fever (p0.0001) were significant predictors for recurrence.Preoperative conditions of patients with NVE significantly affect early and long-term outcomes. Prognosis is worsened by delayed diagnosis and operation during the active septic process.

To evaluate which variables predict recurrence of endocarditis after surgical treatment, we reviewed our 21-year experience.Between January 1979 and May 2000, 308 consecutive valve replacement procedures for infective endocarditis were performed in 271 patients. Univariate and multivariate time-related analyses were performed to retrospectively evaluate the role of the following variables in the development of recurrent postoperative endocarditis: gender, site of endocarditis, previous valve disease, drug abuse, diabetes, positive valve/blood cultures, sepsis, perivalvular involvement, previous embolic events, type of replacement device, and persistent postoperative fever.Clinical and echocardiographic follow-up was 97.36% complete, mean follow-up time was 53.2+/-3.4 months. Recurrent endocarditis developed in 58 cases (22.5%). Variables predicting recurrence were prosthetic endocarditis (p = 0.00001), positive valve culture (p = 0.0039), and persistence of fever at the seventh postoperative day (p = 0.000001).Correct protocols of antibiotic therapy guided by microbiology may reduce the incidence of recurrent endocarditis to allow for surgery on sterile tissues and to prevent prosthetic infection. Recurrence rate is not affected by the choice of valve substitute, but can be prevented by complete surgical debridement.

We report our retrospective experience in the treatment of infective tricuspid endocarditis with valve repair From January 1981 through January 1999, 238 cases of infective endocarditis were seen at our institution, with tricuspid involvement in 19 cases. Tricuspid valve repair was performed in 9 patients whose valves had infective lesions involving a single leaflet. One goal of the repair was to avoid implanting any prosthetic material. At surgery, the posterior leaflet was completely excised and annuloplasty was performed in 4 patients. Wide quadrangular resection of the anterior leaflet and De Vega annuloplasty were performed in the other 5 patients. All patients had a good postoperative recovery Postoperative echocardiography showed no tricuspid regurgitation in 4 patients, mild regurgitation in 3, and moderate in 2. Follow-up ranged from 21 to 155 months (mean, 4756 +/- 50 [SD] months). Two late deaths occurred: one, 2 months postoperatively (sudden death), and the other, 108 months postoperatively (lung carcinoma). Late postoperative echocardiography showed no tricuspid regurgitation in 4 patients, mild in 2, and moderate in 2. No recurrent infection was observed. Tricuspid valve repair rather than valvulectomy or replacement is indicated in cases of right-sided endocarditis with single-leaflet involvement. Tricuspid repair enables eradication of the infection without implantation of prosthetic material.

Cardiovascular disease remains the main cause of death and morbidity in the industrialized world. Atherosclerosis is a slowly progressive disease; coronary artery disease may be the first presentation of a systemic pathology. The association between coronary artery disease and peripheral vascular disease has often been confirmed by multicenter trials; nevertheless it still remains a subject of debate.In order to assess the incidence of coronary artery disease and the degree of associated vascular lesions, between January 1997 and September 1999, in the Department of Cardiothoracic Surgery of the Second University of Naples (Italy), all candidates to coronary artery bypass grafting (CABG) were submitted to routine preoperative echo color Doppler study of the carotid vessels, abdominal aorta and iliac-femoral arteries. The correlation between the echo color Doppler findings, the angiographic patterns of coronary lesions and atherosclerotic risk factors was analyzed in all cases.Among 540 patients undergoing CABG, 418 (77.4%) had carotid disease, with a stenosis70% in 62 (11.3%). Forty-nine (79%) patients had asymptomatic severe carotid disease. A significant correlation between the severity of coronary disease and the incidence of severe carotid disease was found (p = 0.02). An abdominal aortic dilation was found in 37 cases (6.7%). Its diameter exceeded 35 mm in 14 patients (2.5%) and in 8 it was associated with triple vessel coronary disease. Atherosclerotic lesions of the iliac-femoro-popliteal axis were found in 394 (72.9%) patients and strongly correlated with the severity of coronary artery disease (p = 0.02); lesions were hemodynamically significant in 91 (16.8%) cases.Our study emphasizes the association between coronary artery disease and vascular disease. Non-invasive complete arterial investigation should be routinely performed in patients undergoing CABG.

Fecal incontinence, with or without persistent constipation is often underestimated in children affected by spina bifida. Medullar lesions to the L-S metameres result in a slowing of rectal and/or rectal-sigmoid motility, loss of anal or rectal sensation, deranged external anal sphincter function, altered motility of the anal levator muscles, and loss of motor coordination of the internal sphincter. We conducted an electromyographic and electromanometric evaluation of the anorectal tract in a group of children affected by myelomeningocele (MMC) in an attempt to evaluate the degree of functional damage and to provide appropriate treatment.Anorectal manometry was conducted in 83 children affected by MMC (2-16 yrs, mean age: 8.4 yrs); surface electromyography was also performed in 37 of these children. We thus evaluated overall sphincter pressure, the inhibitory anal reflex, the rectal sphincteric reflex and rectal motility during stimulation and at rest. Recording perfusion catheters (0.1 ml/sec) were placed at rectal and anal level; rectal stimulation was conducted with an endorectal balloon.In all patients there was a reduction in overall sphincter pressure (15-25 mmHg; n.v. 45+/-25 mmHg) and the functional length of the anal canal (1-1.8 cm) compared with age matched controls. The inhibitory anal reflex was normal in all patients, although its amplitude, duration and sensitivity were not constant. Similar findings were obtained for the rectal-sphincteric reflex. The rectal sigmoid motility results were difficult to interpret: sudden, fast and high pressure waves of peristaltic progression were followed by prolonged pauses. No correlation was found between urodynamic and anorectal manometric data. Treatment consisted in daily emptying of the rectum so as to avoid fecal retention. Fifteen patients, who presented prolapse and sphincteric hypotonia (/=10 mmHg), underwent cerclage by 2/0 prolene, with sustained good RESULTS.While evaluation parameters of the neuropathic bladder are well standardised, data on the neuropathic rectum are contradictory. Moreover, the results of functional examination are not always an aid to treatment strategy. Therefore, further studies are required to establish an appropriate diagnostic-therapeutic protocol.

To determine objectively, using uroflowmetry, the functional results of the tubularized-incised plate urethroplasty to repair midshaft-proximal hypospadias.Twenty-one patients (mean age 4 years, mean follow-up 1.8 years) were selected from those undergoing surgery between January 1996 and January 1998 at our institution. All patients had midshaft-proximal hypospadias and were treated using the Snodgrass technique. Patients were included if they were able to void volitionally and had no fistula. The flow pattern, maximum (Qmax) and mean flow rate (Qave) were measured; the results were expressed as percentiles and compared with published values from normal children. The Qmax and Qave were considered normal if25th percentile, as equivocally obstructed when in the 5-25th percentile and obstructed if5th percentile.Fourteen patients were considered normal, four as equivocally obstructed and three as obstructed. Of the second group, one patient had a urethral diverticulum at the native meatus (confirmed by voiding cysto-urethrography) and the remaining three patients had meatal stenosis that responded to dilatation, with normal flow in two and improvement in the other. Of the obstructed group, one patient responded to dilatation and two underwent meatoplasty.The tubularized-incised plate repair provides satisfactory functional results for midshaft-proximal hypospadias; uroflowmetry is an important noninvasive tool to evaluate this technique. A long-term follow-up is needed to confirm these results.

The authors report their experience with granulated sugar as dressing technique in the treatment of postoperative mediastinitis refractory to a closed irrigation system.Between January 1990 and January 1998, mediastinitis developed in 61 (0,93%) of 6521 patients who had undergone open heart surgery. Diagnosis of sternal infections was based on wound tenderness, drainage, cellulitis, fever associated with sternal instability. All of them were initially treated with surgical debridement and closed chest irrigation. Nine patients with postcardiotomy mediastinitis refractory to closed chest irrigation underwent open dressing with granulated sugar. All of them were febrile with leukocytosis and positive wound cultures.Bacteria isolated were staphylococcus aureus in 6 cases, staphylococcus epidermidis in 2 and pseudomonas in 1. Redebridement was performed in all cases and the wound was filled with granulated sugar four times a day. Fever ceased within 4.3+/-1.3 days from the beginning of treatment and WBC became normal after 6.6+/-1.6 days. Three patients had hyperbaric therapy as associated treatment. Complete wound healing was achieved in 58.8+/-32.9 days (three patients underwent successful pectoralis muscle flaps).Sugar treatment is a reasonable and effective option in patients with mediastinitis refractory to closed irrigation treatment. It may be used either as primary treatment or as a bridge to pectoralis muscle flaps.

Symptomatic posterior pericardial effusion (PE) represents a diagnostic challenge since it is not easy to quantify by echocardiography. In addition, this type of effusion is normally treated by surgery because of the difficulty in drainage.A 59-year-old male presented a symptomatic circumferential PE following mitral valve substitution. Two days after a successful percutaneous subcostal pericardiocentesis, he reported severe dyspnea with hypotension and pulsus paradoxus. At chest X-rays, he showed a left pleural effusion; echocardiography, also performed from the left posterior axillary line, showed a large posterior PE and a large pleural effusion separated by a membrane. A needle was inserted at the fourth intercostal space 2 cm medially to the left posterior axillary line and advanced into the pleural and then into the pericardial cavity under echocardiographic guidance. Serous-hemorrhagic fluid was drained from the pericardial (800 cc) cavity and, after retraction, from the left pleural cavities (600 cc), with consequent hemodynamic improvement.Pleuro-pericardiocentesis may represent a valid alternative to surgery for the treatment of cardiac tamponade due to posterior pericardial effusions, in the peculiar situation characterized by the simultaneous presence of a left pleural effusion. This procedure should be performed by qualified physicians under echographic guidance.

We describe the long-term results of a case of complete myocardial revascularization with arterial conduit employing also lateral costal artery (LCA). A fifty-four-year-old man underwent revascularization with the implant of right internal artery mammary (RIMA) on the second portion of the right coronary artery (RCA), of the left internal mammary (LIMA) on the left artery descendent (LAD) and of LCA on the obtuse marginal arteries. The postoperative course was uneventful and a twelve-month postoperative coronary angiography showed arterial conduits to be functioning well. LCA is another source for complete myocardial revascularization with arterial conduits.