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Background: We evaluated the reliability of intraoperative assessment of leukocyte esterase (LE) in synovial fluid samples from patients undergoing reimplantation following implant removal and spacer insertion for periprosthetic joint infection (PJI). Our hypothesis was that a positive intraoperative LE test would be a better predictor of persistent infection than either serum C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR) or the combination of serum CRP and ESR. Methods: The records of 76 patients who received a 2-stage exchange for PJI were retrospectively reviewed. Synovial fluid was collected for LE measurement during surgery before arthrotomy in 79 procedures. Receiver operating characteristic curves were generated. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the curve (AUC) of LE, CRP, ESR, and CRP + ESR were calculated. Results: Sensitivity, specificity, positive predictive value, and negative predictive value of the LE assay were 82%, 99%, 90%, and 97%, respectively. Receiver operating characteristic analysis revealed an LE threshold of 1.5 between the first (negative) and the second (positive) level of the ordinal variable, so that a grade starting from 1+ was accurate for a diagnosis of persistent infection (AUC 0.9044). The best thresholds for the CRP and the ESR assay were 8.25 mg/L (82% sensitivity, 84% specificity, AUC 0.8416) and 45 mm/h (55% sensitivity, 87% specificity, AUC 0.7493), respectively. Conclusion: The LE strip test proved a reliable tool to diagnose persistence of infection and outperformed the serum CRP and ESR assays. The strip test provides a valuable intraoperative diagnostic during second-stage revision for PJI.

Li-rich layered oxide materials (LRLOs) are the most promising positive electrodes materials for the next-generation Li-ion batteries. Nevertheless, cycle life stability and capacity retention are still inadequate and hinder their use in the commercial Li-ion devices. In fact, LRLOs undergo structural rearrangements and phase transitions upon cycling that reduce their electrochemical performances. Li1.2Mn0.54Ni0.13Co0.13O2 is one of the most studied LRLO materials, thanks to its high initial specific capacity, exceeding 300 mAh/g in the first cycle, that fades monotonically upon cycling. In this work, after a complete characterization of the pristine material, we demonstrate the electrochemical performances both in half and full cells and we shed new light on the structural degradations occurring upon cycling. By combining ex-situ synchrotron diffraction and Raman spectroscopy, we outline the structural evolution of the LRLO phase occurring in the first 10 cycles of lithium de-intercalation/intercalation, thus extending the understanding of the origin of capacity fading beyond the first cycle.

Background In mouse liver hepatocytes, nearly half of the surface area of every mitochondrion is covered by wrappER, a wrapping-type of ER that is rich in fatty acids and synthesizes lipoproteins (VLDL) (Anastasia et al. in Cell Rep 34:108873, 2021; Hurtley in Science (80- ) 372:142–143, 2021; Ilacqua et al. in J Cell Sci 135:1–11, 2021). A disruption of the ultrastructure of the wrappER-mitochondria contact results in altered fatty acid flux, leading to hepatic dyslipidemia (Anastasia et al. 2021). The molecular mechanism that regulates the extent of wrappER-mitochondria contacts is unknown. Methods We evaluated the expression level of the mitochondrial protein Synj2bp in the liver of normal and obese (ob/ob) mice. In addition, we silenced its expression in the liver using an AAV8 vector. We coupled quantitative EM morphometric analysis to proteomics and lipid analyses on these livers. Results The expression level of Synj2bp in the liver positively correlates with the extent of wrappER-mitochondria contacts. A 50% reduction in wrappER-mitochondria contacts causes hepatic dyslipidemia, characterized by a gross accumulation of lipid droplets in the liver, an increased hepatic secretion of VLDL and triglycerides, a curtailed ApoE expression, and an increased capacity of mitochondrial fatty acid respiration. Conclusion Synj2bp regulates the extent of wrappER-mitochondria contacts in the liver, thus contributing to the control of hepatic lipid flux.

Lithium rich layered oxides (LRLOs) are one of the best alternatives for the next generation positive electrodes materials for Li-ion batteries. However, LRLOs suffer a remarkable voltage decay upon cycling that prevents stable and prolonged electrochemical performances and contains large quantities of cobalt in the transition metal blend. Here, we demonstrate the performance in batteries of a series of innovative materials with general formula Li1.2+xMn0.54Ni0.13Co0.13-x-yAlyO2 (where 0.03≤x ≤ 0.08 and 0.03≤y ≤ 0.05) capable to supply large reversible specific capacities (around 200 mAh g−1), stable cycling performance with reduced voltage decay. This communication sheds light on the interplay between structural and electronic disorder induced by Al/Li co-doping in LRLO and the corresponding functional properties in batteries. The impact of substitution of cobalt by Li and Al co-doping on the structural and morphological properties has been examined by Synchrotron X-ray diffraction (XRD), microwave plasma atomic emission spectrometer (MP-AES) and scanning electron microscopy (SEM). Furthermore, to better understand the structure-function interplay of these over-lithiated materials, ex situ analyses are here reported coupling Synchrotron X-Ray diffraction and Raman Spectroscopy. Based on the obtained results, we proved that coupling the over-lithiation with the aluminum doping, is an effective strategy to reduce the cobalt content into the LRLOs structure maintaining high electrochemical performance. Beside the values of specific capacities obtained in lithium cells, these materials exhibit excellent capacity retention and voltage retention, in particular for the material with the smallest content of cobalt, i.e. Li1.28Mn0.54Ni0.13Co0.02Al0.03O2. Furthermore, thanks to the ex-situ analysis of the latter, we explained the structural evolution of the sample upon cycling that showed the formation of a secondary trigonal phase and the occurrence of limited local distortions of layered structure.

We conducted a systematic review about antibiotic-loaded bone cement (ALBC) with a focus on clinical evidence about ALBC in general, concerns about ALBC and ALBC cost.

Efficient and scalable production of two-dimensional (2D) materials is required to overcome technological hurdles towards the creation of a 2D-materials-based industry. Here, we present a novel approach developed for the exfoliation of layered crystals, i.e., graphite, hexagonal boron nitride and transition metal dichalcogenides. The process is based on high-pressure wet-jet-milling (WJM), resulting in 2 L/hr production of 10 g/L of single- and few-layer 2D crystal flakes in dispersion making the scaling-up more affordable. The WJM process enables the production of defect-free and high-quality 2D-crystal dispersions on a large scale, opening the way for the full exploitation in different commercial applications, e.g., anodes active material in lithium ion batteries, reinforcement in polymer-graphene composites, and transparent conductors as we demonstrate in this report., 30 pages, 15 figures

Objectives: Renal transplant recipients have high mortality from cardiac causes and are frequently in need of coronary interventions. Surgical coronary revascularization is associated with significant morbidity and mortality in this patient population. This study was undertaken to evaluate outcomes of on-pump versus off-pump revascularization in renal transplant recipients. Methods: We retrospectively reviewed 43 renal transplant recipients who underwent surgical coronary revascularization with functioning allografts. Revascularization was performed on-pump [coronary artery bypass grafting (CABG)] in 21 patients and off-pump [off-pump coronary artery bypass (OPCAB)] in 22 patients. Results: Preoperative characteristics did not differ between the two groups except for age and incidence of prior sternotomy. Total operative time and transfusion requirements were similar. The on-pump group received a higher number of bypass grafts (p = 0.03). Overall 30-day, one-year, five-year, and eight-year survival was 90%, 76%, 61%, and 32% for CABG group, and 95%, 86%, 62%, and 48% for OPCAB group (p = 0.53). The postoperative peak creatinine was higher in the CABG patients than in OPCAB patients (p = 0.04). At discharge, there was no difference in mean creatinine between the two groups. The rate of return to permanent dialysis after revascularization was similar (28% for CABG and 22% for OPCAB, p = 0.73). There was no difference in dialysis-free survival up to eight-years postrevascularization (p = 0.63). Conclusions: Despite higher mortality risk, surgical coronary revascularization can be performed safely in renal transplant recipients. OPCAB resulted in no improvement in patient survival or renal allograft function compared to on-pump revascularization. (J Card Surg 2011;26:591-595)

• Background Studies suggest that patients who undergo off-pump coronary artery bypass grafting (OPCABG) have fewer short-term complications and use fewer inpatient resources than do patients who undergo standard coronary artery bypass grafting (CABG) with extracorporeal circulation. However, dissimilarity between groups in risk factors for complications has hindered interpretation of results.• Objectives To compare the prevalence of selected complications (atrial fibrillation, stroke, reoperation, and bleeding) and inpatient resource utilization (length of stay, discharge disposition, total charges) between subjects undergoing primary isolated CABG or OPCABG who were matched with respect to key risk factors.• Methods Retrospective, causal-comparative survey conducted in 1 center for 18 months. Patients who underwent primary isolated CABG or OPCABG were matched for sex, age (within 2 years), left ventricular ejection fraction (within 0.05), and graft-patient ratio (exact match) and compared for prevalence of new-onset atrial fibrillation, stroke, reoperation within 24 hours, and bleeding. Statistical analysis included Wilcoxon and t tests for paired comparisons.• Results The sample (107 matched pairs) was 63% male, with a mean age of 66 (SD 9.5) years, a mean left ventricular ejection fraction of 0.51 (SD 0.13), and a mean graft-patient ratio of 3.41 (SD 0.74). The 2 groups did not differ significantly in New York Heart Association class (P = .43), Acute Physiology and Chronic Health Evaluation III score (P = .22), postoperative β-blocker use (P = .73), or comorbid conditions. None of the complications examined differed significantly between pairs.• Conclusion Patients with comparable risk profiles have similar prevalences of selected complications after CABG and OPCABG.

Vertical heterostructures combining different layered materials offer novel opportunities for applications and fundamental studies of collective behavior driven by inter-layer Coulomb coupling. Here we report heterostructures comprising a single-layer (or bilayer) graphene carrying a fluid of massless (massive) chiral carriers, and a quantum well created in GaAs 31.5 nm below the surface, supporting a high-mobility two-dimensional electron gas. These are a new class of double-layer devices composed of spatially-separated electron and hole fluids. We find that the Coulomb drag resistivity significantly increases for temperatures below 5-10 K, following a logarithmic law. This anomalous behavior is a signature of the onset of strong inter-layer correlations, compatible with the formation of a condensate of permanent excitons. The ability to induce strongly-correlated electron-hole states paves the way for the realization of coherent circuits with minimal dissipation and nanodevices including analog-to-digital converters and topologically protected quantum bits., Comment: 9 pages, 9 figures, 72 references

Abciximab (ReoPro; Eli Lilly and Co, Indianapolis, IN) is a monoclonal antibody that binds to the platelet glycoprotein IIb/IIIa receptor and produces powerful inhibition of platelet function. Clinical trials of abciximab in patients undergoing coronary angioplasty have demonstrated a reduction in thrombotic complications and have encouraged the widespread use of this agent. We have observed a substantial incidence of excessive bleeding among patients who receive abciximab and subsequently require emergency cardiac operations.The records of 11 consecutive patients who required emergency cardiac operations after administration of abciximab and failed angioplasty or stent placement were reviewed.The interval from the cessation of abciximab administration to operation was critical in determining the degree of coagulopathy after cardiopulmonary bypass. The median values for postoperative chest drainage (1,300 versus 400 mL; p0.01), packed red blood cells transfused (6 versus 0 U; p = 0.02), platelets transfused (20 versus 0 packs; p = 0.02), and maximum activated clotting time (800 versus 528 seconds; p = 0.01) all were significantly greater in the early group (cardiac operation12 hours after abciximab administration; n = 6) compared with the late (cardiac operation12 hours after abciximab administration; n = 5) group.This report suggests that the antiplatelet agent abciximab is associated with substantial bleeding when it is administered within 12 hours of operation.

BACKGROUND: Cryptogenic fibrosing alveolitis (CFA) is an uncommon disorder of unknown aetiology characterised by interstitial fibrosis which typically shows a restrictive pattern on pulmonary function testing. Some patients with CFA and relative preservation of lung volumes have been described and it has been suggested that their volume preservation may be due to concomitant emphysema. In a retrospective study the relative frequency of preserved lung volumes in CFA, its relationship to emphysema determined by CT scanning, its clinical features, and its subsequent natural history were investigated. METHODS: Using predefined characteristics 48 patients with CFA were identified from pulmonary function records over a three year period. Volume preservation was defined as a forced vital capacity (FVC) of > 80% predicted at presentation. Patients with relative volume preservation were compared with those with more typical pulmonary restriction and clinical data at presentation, and details of their subsequent prognosis, treatment and loss of lung function with time were obtained. Where available, computed tomographic (CT) scans for the two groups were compared in a blinded fashion to score the extent of fibrosis and the presence of concomitant emphysema. RESULTS: Twenty one (44%) of the patients with CFA had a FVC of > 80% predicted. They were more likely to be male (76% versus 48%) and to be current smokers (57% versus 22%) with a heavier life time cigarette consumption than the restricted patients (mean (SE) 38 (4.6) versus 25 (4.5) pack years). There were no significant differences in prognosis and subsequent treatment between the groups. Comparable HRCT scans were available in 23 subjects (seven preserved, 16 restricted). They showed no difference in extent of the pulmonary fibrosis but patients with volume preservation were more likely to show concomitant emphysema (86% versus 19%). Patients with emphysema on HRCT scans were heavier smokers (41(10) versus 21(17) pack years) than those without emphysema but there was no difference in the extent of CFA score between the two groups. CONCLUSIONS: In this area of high smoking prevalence a significant number of patients with CFA presented with relative preservation of lung volumes and FEV1/FVC ratio. In many of these subjects this appears to reflect coincidental emphysema. This may make interpretation of gas transfer factor used to monitor progression in CFA difficult. However, there was no evidence that lung volumes at presentation were of prognostic significance.

We experimentally investigate the temperature (T) dependence of the resistance of a classical ballistic point contact (PC) in a two-dimensional electron system (2DES). The split-gate PC is realized in a high-quality AlGaAs/GaAs heterostructure. The PC resistance is found to drop by more than 10% as T is raised from 0.5 K to 4.2 K. In the absence of a magnetic field, the T dependence is roughly linear below 2 K and tends to saturate at higher T. Perpendicular magnetic fields on the order of a few 10 mT suppress the T-dependent contribution ?R. This effect is more pronounced at lower temperatures, causing a crossover to a nearly parabolic T dependence in a magnetic field. The normalized magnetic field dependencies ?R(B) permit an empiric single parameter scaling in a wide range of PC gate voltages. These observations give strong evidence for the influence of electron-electron (e-e) scattering on the resistance of ballistic PCs. Our results are in qualitative agreement with a recent theory of the e-e scattering based T dependence of the conductance of classical ballistic PCs [ Phys. Rev. Lett. 101 216807 (2008) and Phys. Rev. B 81 125316 (2010)].

Immature rats are able to give maternal care to pups and may increase their inclusive fitness by helping newborn siblings. Immature males are generally reported to be more maternal than females. In this research we studied sex differences and the extent to which they may be due to a different emotional response to novelty. We studied maternal response in two groups of immature rats of both sexes: in the naive group, juveniles aged from 18 to 30 days were given one test and showed clear-cut sex differences. The experience group was submitted to repeated tests from 18 to 30 days of age, thus eliminating the effects of novelty: as a result, all differences between sexes disappeared. A second experiment was designed in 24-day-old females to differentiate the effects of repeated handling and exposure to the test situation from that of repeated exposure to pups; moreover, the effects of an anxiety-reducing drug (diazepam) were studied. Exposure to pups is particularly efficient in facilitating maternal response. Diazepam injection was also effective, but its control showed that the injection per se was responsible for the effect. In conclusion, our results stress the importance of response to novelty and suggest that sex differences in maternal behavior of immature rats may be modulated by different emotional responses by males and females. In fact, emotionality competes with, and may exert an inhibitory effect on, the expression of a vast array of behaviors. © 1994 Wiley-Liss, Inc.

We observed room-temperature intersubband transitions at 1.26 microns in n-doped type-II In$_{0.3}$Ga$_{0.7}$As/AlAs strained quantum wells. An improved tight-binding model was used to optimize the structure parameters in order to obtain the shortest wavelength intersubband transition ever achieved in a semiconductor system. The corresponding transitions occur between the first confined electronic levels of the well following mid-infrared optical pumping of electrons from the barrier X-valley into the well ground state., To appear in Applied Physics Letters

We observe a low-lying sharp spin mode of three interacting electrons in an array of nanofabricated AlGaAs/GaAs quantum dots by means of resonant inelastic light scattering. The finding is enabled by a suppression of the inhomogeneous contribution to the excitation spectra obtained by reducing the number of optically probed quantum dots. Supported by configuration-interaction calculations we argue that the observed spin mode offers a direct probe of Stoner ferromagnetism in the simplest case of three interacting spin one-half fermions.

PURPOSE To describe a novel percutaneous technique for distal limb perfusion in the face of femoral artery occlusion secondary to extracorporeal membrane oxygenation (ECMO) cannula placement. TECHNIQUE The technique is described in a 59-year-old man who presented with an inferior wall myocardial infarction and a large ventricular septal defect (VSD) requiring the initiation of ECMO via right femoral artery and vein cannulae. He subsequently developed right lower limb ischemia secondary to cannula occlusion of the femoral artery. Percutaneous transfemoral placement of a flush catheter in the right common femoral artery was performed angiographically. Ischemic symptoms resolved, and the patient was subsequently able to undergo repair of his VSD without any further lower limb ischemic sequelae. CONCLUSION Percutaneous transfemoral placement of a flush catheter in the common femoral artery distal to ECMO cannula insertion has not to our knowledge been reported and carries the added benefit of restoring perfusion to both superficial and profunda femoris arteries.

Purpose On-pump coronary artery bypass graft (CABG) surgery has been traditionally associated with a higher magnitude of inflammatory response than off-pump CABG. However, with the development of polymer-coated biocompatible extracorporeal circuits, we wanted to see if cardiopulmonary bypass still played an important role in triggering this inflammatory response. Methods In this prospective observational study, 33 patients undergoing CABG surgeries (25 on-pump and 8 off-pump patients) were studied. Serial plasma cytokine (TNF, IL-6, IL-10) and procalcitonin concentrations were measured at different time-points during and after the surgery. Demographic and baseline clinical data, intra-operative management details and post-operative complications were also collected from the patients' charts. Results Plasma levels of all 4 mediators increased during surgery and returned towards normal post-operatively. There were no differences between groups for any mediator at any time-point. Conclusions We conclude that with the use of recent polymer-coated biocompatible extracorporeal circuits, the inflammatory response triggered by on-pump CABG becomes very similar in magnitude and pattern to that triggered by off-pump CABG. Thus, the surgical procedure contributes to most of the inflammatory response, with the extra-corporeal circuit having minimal to no effect on this response.

Particle‐hole symmetry is a central concept in the quantum Hall effects and is invoked to explain the observation of incompressible quantum Hall states for symmetric filling factors ν ⇆ 1 − ν. We report finite‐bias measurements of the current transmission through a split‐gate constriction in the quantum Hall regime displaying signatures linked to the presence of this symmetry. Experimental data are also discussed in light of the Luttinger model for edge channels. We show how particle‐hole duality can be exploited to design QH circuits where transport can be more easily interpreted in terms of “holes” in a filled Landau level.

A 20-year-old man with no significant past medical history presented with sudden onset of sharp right temporal headache and left-sided weakness. He also noticed some visual disturbance in the left eye. His symptoms lasted about 6 h and then resolved. There was no history of recent trauma or drug abuse. There was a family history of stroke, which had affected his aunt and grandfather. He was normotensive and in sinus rhythm. Cardiovascular examination was normal and neurological examination confirmed a mild left-sided weakness and left facial droop. Unenhanced cranial CT and baseline blood tests were performed on the same day as the event and demonstrated no abnormality. Urgent carotid Doppler US on the following day showed normal Doppler parameters in the left extracranial carotid circulation. However, the right common carotid artery (RCCA) waveform demonstrated flow reversal in early diastole (Fig. 1(a)) when compared with the

Studies suggest that patients who undergo off-pump coronary artery bypass grafting (OPCABG) have fewer short-term complications and use fewer inpatient resources than do patients who undergo standard coronary artery bypass grafting (CABG) with extracorporeal circulation. However, dissimilarity between groups in risk factors for complications has hindered interpretation of results.To compare the prevalence of selected complications (atrial fibrillation, stroke, reoperation, and bleeding) and inpatient resource utilization (length of stay, discharge disposition, total charges) between subjects undergoing primary isolated CABG or OPCABG who were matched with respect to key risk factors.Retrospective, causal-comparative survey conducted in 1 center for 18 months. Patients who underwent primary isolated CABG or OPCABG were matched for sex, age (within 2 years), left ventricular ejection fraction (within 0.05), and graft-patient ratio (exact match) and compared for prevalence of new-onset atrial fibrillation, stroke, reoperation within 24 hours, and bleeding. Statistical analysis included Wilcoxon and t tests for paired comparisons.The sample (107 matched pairs) was 63% male, with a mean age of 66 (SD 9.5) years, a mean left ventricular ejection fraction of 0.51 (SD 0.13), and a mean graft-patient ratio of 3.41 (SD 0.74). The 2 groups did not differ significantly in New York Heart Association class (P = .43), Acute Physiology and Chronic Health Evaluation III score (P = .22), postoperative beta-blocker use (P = .73), or comorbid conditions. None of the complications examined differed significantly between pairs.Patients with comparable risk profiles have similar prevalences of selected complications after CABG and OPCABG.

Notwithstanding the presence of numerous examinations for screening coeliac disease, it may still escape timely diagnosis. For this reason we carried out an investigation to see whether simple haematochemical anomalies (as revealed in what are now routine examinations carried out during hospitalisation) might make diagnosis quicker or at least trigger the suspicion of coeliac disease.Retrospectively, of 21 adult patients admitted to our hospital for the first time and who were diagnosed with coeliac disease, we considered haemoglobin, iron, calcium, potassium, albumin and RDW (part of the normal blood count).We found that elevated RDW was the most frequent anomaly (67% of patients) of the six haematochemical parameters observed. In addition, it became normal in most patients after a gluten-free diet.Elevated RDW was more frequent than sideropenic anaemia in patients with coeliac disease. In addition, RDW indicates a response to diet therapy because it became normal after a gluten-free diet.

Background Antifibrinolytic medications administered before skin incision decrease bleeding after cardiac surgery. Numerous case reports indicate thrombus formation with administration of epsilon-aminocaproic acid (epsilon-ACA). The purpose of this study was to examine the efficacy of epsilon-ACA administered after heparinization but before cardiopulmonary bypass in reducing bleeding and transfusion requirements after primary coronary artery bypass surgery. Methods Seventy-four adult patients undergoing primary coronary artery bypass surgery were randomized to receive 125 mg/kg epsilon-ACA followed by an infusion of 12.5 mg x kg(-1) x h(-1) or an equivalent volume of saline. Coagulation studies, thromboelastography, and platelet aggregation tests were performed preoperatively, after bypass, and on the first postoperative day. Mediastinal drainage was recorded during the 24 h after surgery. Homologous blood transfusion triggers were predefined and transfusion amounts were recorded. Results One patient was excluded for surgical bleeding and five patients were excluded for transfusion against predefined criteria One patient died from a dysrhythmia 2 h postoperatively. Among the remaining 67, the epsilon-ACA group had less mediastinal blood loss during the 24 h after surgery, 529+/-241 ml versus 691+/-286 ml (mean +/- SD), P < 0.05, despite longer cardiopulmonary bypass times and lower platelet counts, P < 0.05. Platelet aggregation was reduced in both groups following cardiopulmonary bypass but did not differ between groups. Homologous blood transfusion was similar between both groups. Conclusions Prophylactic administration of epsilon-ACA after heparinization but before cardiopulmonary bypass is of minimal benefit for reducing blood loss postoperatively in patients undergoing primary coronary artery bypass grafting.

An unusual case of multiple myeloma is reported in a 61-year-old man presenting with hepatomegaly and multiple hypoechoic lesions in the liver seen on ultrasound. Following cytotoxic chemotherapy the size and number of the lesions within the liver had significantly reduced.

Four thousand four hundred and thirty open heart operations were performed at Mercy Hospital of Pittsburgh from January 1, 1988, to June 30, 1992. During that period, 168 patients were evaluated for recurrent ischemic heart disease after prior coronary artery revascularization. Forty-four were treated non operatively, the mode of therapy being transluminal angioplasty or medical management. The remaining 124 patients underwent repeat coronary revascularization. An attempt was made to define the impact of advancing age on the magnitude of risk factors, morbidity, and mortality. Advancing age is not a contraindication to repeat coronary artery revascularization. The average interval between the initial operation and the need for repeat revascularization is eight years. Younger patients have progression of their coronary artery disease, but progression of the arteriosclerotic process is in their extracranial cerebral arteries, renal arteries, and aortic segments as well as the coronary arteries. The utilization of tobacco, recent myocardial infarction, diabetes mellitus, and elevation of cholesterol are strong indicators for recurrent disease and add to the risk of repeat surgical intervention.

Chlamydia pneumoniae is the third strain of Chlamydia and transmission is presumed to be by droplet spread from symptomatic patients. The authors show a literature scientific review on subject-matter emphasizing several sporadic and epidemic case of illness in every age, first months excepted. The described cases are few and therefore clinical characteristics are shadowy. Certain clinical features are suggesting of severe pneumonia with fever and pharyngitis without exudate. In the childhood and in the adolescence the clinical evolution is favourable. Tetracyclines or erythromycin is recommended for therapy.

The authors show a scientific literary review on Ch. trachomatis pneumonia. A distinctive syndrome pneumonia has been reported in infants infected by Chlamydia (at 2-3 months of age) in genital-urinary infected mothers. The infection may be preceded by conjunctivitis, in apyrexia followed by attacks of coughing pertussis-like. Blood eosinophilia is present. Although favorable prognosis in infancy, erythromycin is the drug of choice shortening the clinical course erythromycin is also recommended in woman infected prevention.

The authors show a literary review on Mycoplasma pneumonia which represents a fifth of human pneumonia. M. pneumoniae is the major cause of illness in school-age children (5-9 years) and young adults and the peak incidence of illness occurs in this age. The infection appears mainly as an interstitial pneumonitis and the onset of illness is gradual, influence-like with few clinical symptoms and typical roentgenographic and bronchoscopic findings. Cold hemagglutinins appear in approximately 50% of patients. A severe prognosis can be associated with extrarespiratory symptoms; Erythromycin (as others macrolides) is the drug of choice.

Pneumonia due to L. pneumophila occurs frequently in children even though "legionnaires' disease" in adults in usual. The authors show a literary scientific review of almost one hundred cases, sporadic generally, in childhood. In children legionnaires' disease remembers the adults infection, beginning with bronchiolitis. The extrarespiratory symptoms appears more frequently in adults. Chest roentgenograms obtained early reveal patchy infiltrates that become nodular areas of consolidation bilateral also, with pleural effusion. In children prognosis is poor (exitus in 15 about 97 described cases). The infection responds to erythromycin; it is administered intravenously, but oral treatment may also be used.

Unilateral absence of pulmonary artery is a rare malformation that can present as an isolated lesion or may be associated with other congenital heart defects. Clinical presentation is subtle when the lesion occurs alone, and may include hemoptysis, which results from rupture of abundant bronchial submucosal vessels perfused by enlarged systemic collaterals that supply the affected lung. Pneumonectomy is recommended as definitive treatment in such an adult patient.

The authors report a case of hemiballismus in an old patient with diabetes and hypertension, developed after a non ketotic hyperosmolar coma episode. In agreement with the recent literature, the syndrome is not always caused by a single Luys body lesion, but also by complex scattered lesions demonstrable only by RMN. A possible pathogenetic role of the recent non ketotic hyperosmolar diabetic coma and the good prognosis indicate that the vascular aetiology, even if prevalent, could not be the only one. The role of institutionalization of the patient during the development of the syndrome has also been discussed.

Normothermic retrograde continuous cardioplegia is a revolutionary development for myocardial preservation in cardiac surgery. Despite excellent reports regarding this technique, the surgical community has expressed concern over technical problems encountered. The method of normothermic retrograde continuous cardioplegia in current use requires both large total crystalloid volumes and large potassium loads to deliver adequate cardioplegia. We have developed a technique that eliminates these problems. The heart is stopped by an initial infusion of normothermic cardioplegic solution through a coronary sinus catheter. The infusate is then converted to normothermic pump blood. Small boluses of potassium chloride are added intermittently to maintain cardiac arrest. We applied this technique to 35 patients undergoing cardiac valve surgery. The average volume of crystalloid cardioplegia required was 125 mL (range, 40 to 155 mL), and the average total potassium load was 52 mEq (range, 2 to 100 mEq). Clinically significant sequelae were noted in 4 patients (11%), and 1 (3%) died of pneumonia on the 28th postoperative day. The method we describe is a safe and effective alternative to the current technique of normothermic retrograde continuous cardioplegia and offers both physiologic and technical advantages to patients undergoing cardiac valve procedures.

The magnetic-field evolution of Coulomb blockade peaks in lateral In0.75Ga0.25As/In0.75Al0.25As quantum dots in the few-electron regime is reported. Quantum dots are defined by gates evaporated onto a 60-nm-thick hydrogen silsesquioxane insulating film. A gyromagnetic factor g∗≈4.4 is measured via zero-bias spin spectroscopy and a transition from singlet to triplet spin configuration is found at an in-plane magnetic field B=0.7 T. This observation opens the way to the manipulation of singlet and triplet states at moderate fields and its relevance for quantum information applications will be discussed.

Assuring the complete inactivation of hepatitis A virus (HAV) vaccine commonly requires prolonged tissue culture amplification, followed by detection of virus antigen in cell lysates. A reliable, but faster, alternative procedure is highly desirable since it will permit the prescreening of experimental batches of killed HAV, prior to tissue-culture amplification. We established experimental conditions for simultaneous, polymerase chain reaction (PCR)-based amplification of viral and cellular mRNA sequences from infected cell RNA (compound PCR). Under these conditions, the presence of virus-specific amplified sequences, as detected by Southern blot, allows the identification of incompletely inactivated vaccine batches with a threshold practically identical to that of the more time-consuming subculture and ELISA. Compound PCR is, by its nature flexible enough for adaption to different requirements and it should prove useful for rapid prescreening of vaccine batches and pilot studies for improvement of inactivation protocols.

The authors describe, in a patient suffering from IDDM, a case of suspected EHS the beginning of which was concealed by serious ketoacidosis. The clinical suspicion, strengthened by the tests TC and RMN, was not confirmed by CSF analysis. In spite of the severity of the documented lesion and neurological findings at the onset and the outcome has turned out favourably.

A reduction in the number of radiographs for many investigations has been advocated. This study aims to assess the need for control views in sialography and whether the post-contrast lateral oblique radiograph would be satisfactory, at least initially, as the sole standard post-contrast film.

Se estudio la influencia de diferentes intensidades de manejo sobre el sotobosque de plantaciones de pino ponderosa en parcelas distribuidas en una transecta O-E. Cinco bajo bosque de Nothofagus y diez bajo pino —cinco con 90-100% de cobertura y cinco con una reduccion al 60-70%— y otras dos bajo estepa y sus equivalentes bajo pinos sin raleo y raleado. Se calculo el indice de diversidad de Shannon, y se caracterizo y comparo el suelo superficial. Bajo pino la diversidad fue menor que bajo vegetacion natural —Nothofagus y estepa— lo que junto con el menor contenido de carbono del suelo evidenciaron la alteracion del ecosistema. La diversidad bajo pino raleado respecto al no raleado fue mayor y dominada por especies herbaceas exoticas y arbustos nativos, reflejandose en la estructura del suelo superficial, que tendio a granular como bajo vegetacion natural, mostrando su capacidad de resiliencia. El raleo favorecio el desarrollo del sotobosque bajo pino ponderosa, tendiendo a la restauracion de la biodiversidad, lo que se deberia a la mayor radiacion recibida. De la composicion del sotobosque y su efecto sobre los primeros centimetros del suelo, se podrian derivar estrategias de manejo apuntando a lograr la diversificacion de los sistemas productivos.

Background An unusual sequence of post operative events heralded by hemodynamic deterioration followed by dyspnea and rapidly progressive dilatation of superficial neck and facial veins, resembling a superior vena cava syndrome, two days post surgical resection of filamentous aortic valve masses, closure of a patent foramen ovale, and performance of a modified Maze procedure for atrial fibrillation in a patient that presented with transient neurologic findings is presented. Case Presentation Although both clinical findings and hemodynamic derangements completely resolved following tricuspid valve repair aimed to correct the new onset severe tricuspid regurgitation noted post operatively; a clear mechanism was not readily obvious and diagnostic testing data somewhat conflictive. We present a careful retrospective examination of all clinical data and review possible clinical entities that could have been implicated in this particular case and recognize that transesophageal echocardiographic findings were most useful in identifying the best course of action. Conclusion After reviewing all clinical data and despite the inconclusive nature of test results; the retrospective examination of transesophageal echocardiographic findings proved to be most useful in identifying the best course of action. We postulate that in our case, resolution of the suspected pulmonary embolism with anticoagulation and reestablishment of a normal right ventricular geometry with tricuspid valve repair worked in unison in restoring normal hemodynamics and resolving both dyspnea and venous dilatation.

We report conductance measurements in quantum wires made of aluminum arsenide, a heavy-mass, multi-valley one-dimensional (1D) system. Zero-bias conductance steps are observed as the electron density in the wire is lowered, with additional steps observable upon applying a finite dc bias. We attribute these steps to depopulation of successive 1D subbands. The quantum conductance is substantially reduced with respect to the anticipated value for a spin- and valley-degenerate 1D system. This reduction is consistent with disorder-induced, intra-wire backscattering which suppresses the transmission of 1D modes. Calculations are presented to demonstrate the role of strain in the 1D states of this cleaved-edge structure., Comment: Submitted to Applied Physics Letters

An unusual case of multiple myeloma is reported in a 61-year-old man presenting with hepatomegaly and multiple hypoechoic lesions in the liver seen on ultrasound. Following cytotoxic chemotherapy the size and number of the lesions within the liver had significantly reduced.