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Coronary artery bypass grafting for the treatment of unstable angina is still associated with increased operative risk and postoperative morbidity. The impact of the extended use of arterial grafts on early results is incompletely defined. In a 7-year period (1986 to 1993), 474 patients (average age, 65 years; range, 34 to 85 years) underwent coronary artery bypass grafting for the treatment of unstable angina. Sixty-eight patients were operated on emergently and 406 urgently. They received an average of 3.0 distal anastomoses (range, 1 to 6). Seventy-nine patients had exclusively venous grafts, 316 had one internal thoracic artery graft, 79 had bilateral internal thoracic artery grafts, and 20 had inferior epigastric artery grafts. Sequential internal thoracic artery grafting was performed in 70 patients. Redo operations were performed in 26 patients. Thirty-four patients (7.2%) experienced a new myocardial infarction. Eighty-nine patients (18.8%) had an intraaortic balloon pump inserted preoperatively, intraoperatively, or postoperatively. Eight patients (1.7%) died intraoperatively and 24 patients (5.1%) died postoperatively. Seventy-seven patients (16.2%) had an adverse outcome, as shown by the need for an intraaortic balloon pump (intraoperatively or postoperatively) or hospital death, or by both. Forty variables were examined by multivariate analysis for their influence on the occurrence of an adverse outcome. Aortic cross-clamp time (p = 0.0004), transfer from the intensive care unit (p = 0.0023), female sex (p = 0.0023), operation performed in early years (p = 0.0041), left ventricular aneurysm (p = 0.0068), the number of diseased coronary vessels (p = 0.0312), and reoperation (p = 0.0318) were all found to be significant independent predictors of increased risk.(ABSTRACT TRUNCATED AT 250 WORDS)
1. This work was undertaken in order to study whether the opioid system is involved in the modulation of the behaviors induced by two agonists of the dopaminergic system, amphetamine and apomorphine in adult cats. 2. Naloxone, an antagonist of the mu, delta and kappa opioid receptors was administered to twelve female mongrel cats; 0.5, 1.0 and 2.0 mg/kg s.c. were injected in order to analyse its own effect of naloxone. This drug produced NREMs behavior and accordingly the cat showed an overall decrease of its activities. 3. Amphetamine (2.5 mg/kg s.c.) and apomorphine (2.0 mg/kg s.c.) were injected before and after naloxone administration (2.0 mg/kg s.c.), in separate sessions. 4. The behaviors recorded were compared. Some of the behaviors showed modifications both with amphetamine (inappetence was increased and locomotion decreased) and apomorphine (indifference and inappetence increased; locomotion and olfaction decreased). 5. These changes were considered as consequence of the NREMs behavior induced by naloxone and not as a result of a modulation by the opioid system of the activation of the dopaminergic system elicited by amphetamine and apomorphine. Regarding the mechanism of NREMs induced by naloxone probably the dopaminergic, noradrenergic and GABAergic systems may be involved.
Cell-cell and cell-extracellular matrix interactions mediated by cell adhesion molecules (for example CD44) play an important role in the cascade of metastasis and the progression of human malignant tumours. The most important aim of this review was, on the basis of our results and the literature, to show the correlation between the expression of CD44s and differentiation and prognosis of neuroblastoma. Surprisingly and in contrast to most other malignant tumours, neuroblastomas exhibited an inverse correlation between CD44s expression and tumour progression. It can be stated that CD44s is a prognostic marker in neuroblastoma which correlates significantly with the grade of tumour cell differentiation, but not with clinical stage. Moreover, there exists a statistically significant correlation between MYCN oncogene amplification and the lack of CD44s expression.
In this paper three different areas of the biology of multiple myeloma (MM) are reviewed: (1) the immunophenotypic characteristics of plasma cells (PC), (2) the changes in the immunoregulatory cells, and (3) the cell DNA content of PC. Myelomatous PC display a heterogeneous phenotype not only between different patients but also within each patient consistent with the fact that the neoplastic clone is able to undergo a certain degree of differentiation. In addition, PC generally lack surface B cell associated antigens and infrequently show reactivity for non-lineage restricted markers. The B-B4 and CD38 are the two best markers for identifying PC which are crucial for the correct assessment of other antigens by multiple staining procedures. Moreover, some of the antigens present in PC such as CD56, CD20, CD10, CD28 and SIg may have prognostic implications. Whether or not normal PC are phenotypically different from myelomatous PC remains controversial although some antigenic combinations such as CD19-/CD56++ could probably help to identify the malignant nature of PC. Both T and NK cells are markedly altered in MM patients probably reflecting a host-tumour immunological interaction. The reduction in CD4 cells correlates both with advanced clinical stage and poor survival. As far as NK cells are concerned, there is an overall increase in peripheral blood and BM in MM patients but the changes observed are heterogeneous, reflecting the existence of different NK cell subsets. This fact could explain the contradictory results observed in the literature. Accumulating evidence exists that the measurement of cell DNA content by flow cytometry is a useful parameter in the clinical evaluation of MM patients. Between 50 and 70% of MM patients display DNA aneuploidy with the majority of them hyperdiploid. Upon comparing hyperdiploid with diploid patients, the former usually display a better prognosis. The possibility of analysing the cell cycle distribution by using a PI/CD38 double staining technique may be an alternative to other more laborious methods of assessing the PC labelling index. In our experience, patients with > 3% S phase PC have an adverse prognosis and this parameter was the most important independent prognostic criteria for predicting survival.
We have traced the rapid molecular evolution of eosinophil-derived neurotoxin (EDN) and eosinophil cationic protein (ECP), two host defense proteins that are members of the mammalian ribonuclease gene family. The EDN/ECP gene pair arose from a recent duplication event that occurred after the divergence of New World and Old World monkeys. Since duplication, the genes encoding EDN and ECP have accumulated non-silent mutations at rates exceeding those of all other functional coding sequences studied in primates, while retaining both the structural and catalytic components required for ribonuclease activity. These results suggest that both EDN and ECP may be responding to unusual evolutionary constraints, which has prompted a reexamination of their physiologic function.
We performed a clinical and pathological study of a 5 year old female mongrel dog (Drahthaar) with eosinophilic gastroenteritis. The animal was presented with vomiting and was reported to have had bloody diarrhoea for 4 months. The lesions were in atypical locations: in the fundus of the stomach, the ileocaecal valve and the rectum, near the anal sphincter. The lesions in the stomach wall were particularly severe and included severe fibroplasia, especially in the muscle layer and submucosa. Fibroplasia was less visible in the other locations. The presence of eosinophilic granulomatous masses led us to suspect a possible parasitic infection, although some authors note that this pathological condition may have an allergic aetiology.
OBJECTIVE: To document the action of erythromycin on gastric emptying and motility in mechanically ventilated patients. DESIGN: Crossover, double-blind, randomized, placebo-controlled study. SETTING: General intensive care unit in a university hospital. PATIENTS: Ten patients, mechanically ventilated, in a stable hemodynamic condition. INTERVENTIONS: Erythromycin (200 mg i.v. over 30 mins) and placebo were infused at mid-morning, on two consecutive days, in a random order. Pressure changes in the gastric antrum were recorded by means of a multi-lumen manometric tube (perfused catheter technique) over a period of 300 mins, beginning with the institution of the erythromycin or placebo infusion. Gastric emptying was simultaneously assessed by the kinetics of the absorption of acetaminophen delivered into the stomach (1 g with 20 mL of water) immediately before the infusion. MEASUREMENTS AND MAIN RESULTS: Motility was quantified by determining the number of contractions, the amplitude of contractions, and the Motility Index (Motility Index = natural logarithm [sum of amplitude x number of contractions] + 1). Comparison between placebo and erythromycin was made for the first hour after the infusion and for the whole recording session. The maximal acetaminophen concentration, the time to reach the peak acetaminophen concentration, and the area under the concentration-time curve at 60 mins were obtained from serial determinations of plasma acetaminophen concentrations. Compared with placebo, the mean number of contractions (104 +/- 34 vs. 5 +/- 8; p = .003), the mean amplitude of contractions (52 +/- 16 vs. 20 +/- 17 mm Hg; p = .005), and the Motility Index (13.06 +/- 0.95 vs. 4.45 +/- 3.54; p = .004) were significantly increased during the first hour after erythromycin infusion compared with placebo. Number of contractions (p = .017) and Motility Index (p < .001) after erythromycin infusion remained significantly higher when values throughout the whole recording session were considered. The following data were noted after erythromycin was infused: a) the time to reach the peak acetaminophen concentration was shorter (32 +/- 8 vs. 171 +/- 93 mins; p = .007); b) the maximal acetaminophen concentration was higher (22.09 +/- 6.23 vs. 5.38 +/- 3.80 micrograms/mL; p = .007); and c) the area under the concentration-time curve at 60 mins increased markedly (730 +/- 269 vs. 72 +/- 42 micrograms/min/mL; p = .002) as compared with placebo. CONCLUSION: In mechanically ventilated patients, intravenous erythromycin (200 mg over 30 mins) increases indices of antral motility and accelerates gastric emptying as assessed by the kinetics of acetaminophen absorption.
A common misconception among microsurgeons is that free tissue failure is an "all-or-none" phenomenon. In other words, there is an instantaneous cessation of blood flow to a flap primarily due to thrombosis at the arterial or venous anastomotic site (primary thrombosis) with complete flap loss as a result. Contrary to this belief, we have found that free tissue transfers occasionally "die" a slow, progressive, and partial death. This most likely is due to gradual "shutting down" of the microcirculation by the showering of microemboli downstream from the arterial anastomosis (secondary thrombosis). We discuss our clinical experience during the past 6 years with 10 patients in whom free flap failure was not an all-or-none phenomenon and describe the expectant management of these failing free flaps. Microvascular reconstruction of the lower extremities was performed for recalcitrant sickle cell ulceration, chronic venous stasis ulceration in a patient with anti-thrombin III deficiency, dry gangrene of the plantar surface of the foot and toes secondary to posterior tibial artery injection in an intravenous drug abuser, Gustillo type IIIc injury requiring reconstitution of the femoropopliteal artery after an automobile bumper injury, Gustillo type IIIb injury resulting from gunshot wounds, an open ankle joint in a patient with severe peripheral vascular disease, and osteomyelitis. Other cases included cheek soft tissue reconstruction after wide resection of a recurrent dermatofibrosarcoma protuberans of the parotid gland, chest wall coverage after claviculectomy for osteoradionecrosis, and thumb replantation complicated by refractory vasospasm. Latissimus dorsi (four patients), rectus abdominis (three patients), scapular (one patient), and radial forearm fasciocutaneous (one patient) flaps were used. Flap compromise was detected between 4 hours and 6 weeks after surgery. Salvage attempts included Fogarty thrombectomy (four patients), anastomotic revision (two patients), streptokinase instillation (one patient), and leech application (one patient). Failing free flaps were managed expectantly with the use of daily dressing changes. This allowed for the survival of sufficient soft tissue to effect coverage of exposed bone, tendon, or joint. Hyperbaric oxygen was not administered. Tangenital excision of the eschar was performed between 6 and 51 days after free tissue transfer. Skin grafting was delayed for 15 to 80 days. In all cases, a successful outcome was achieved ultimately by either a single skin-grafting procedure (seven patients) or groin flap coverage (one patient). Follow-up ranged from 2 to 35 months.(ABSTRACT TRUNCATED AT 250 WORDS)
Bone marrow stromal cells synthesize and secrete insulin-like growth factor (IGF)-I and IGF-binding proteins (IGFBP). IGFBPs may modulate the action of IGF-I or IGF-II on haemopoiesis. However, the specific IGFBPs produced by various stromal cell types have not been identified. We examined six different stromal phenotypes for IGFBP protein and IGFBP-1 to -6 mRNA expression. [125I]IGF-I ligand blot analysis of conditioned medium demonstrate different patterns of IGFBP secretion by each cell type. The most prominent IGFBPs were 24 and 29 kD species, consistent with IGFBP4 and IGFBP5, respectively. RNase protection assays demonstrate that, overall, stromal cells express IGFBP-2 to -6 mRNAs, with IGFBP4, IGFBP5 and IGFBP6 mRNAs predominating. Since agents that modulate cAMP levels may influence haemopoiesis via the release of stromal-derived cytokines, we determined the effect of forskolin, a cAMP agonist, on IGFBP4 expression in TC-1 cells. Forskolin (10(-5) M) up-regulated IGFBP4 mRNA and protein secretion in a time-dependent manner. These findings suggest that IGFBP-4, -5 and -6 released by stromal cells may be key modulators of the haemopoietic response to IGFs. Release of IGFBP4 by agents that increase cAMP may be an important mechanism involved in regulating IGF bioavailability in the marrow microenvironment.
Third-generation implantable cardioverter defibrillators (ICDs) offer tiered therapy and can provide significant advantage in the management of patients with life-threatening arrhythmias. Three different types of ICDs were implanted in 21 patients with ventricular tachycardia (VT) or ventricular fibrillation (VF). Arrhythmia presentation was VT (76%), VF (10%), or both (14%). The mean left ventricular ejection fraction for the group was 32.4 +/- 7%. No surgical mortality occurred. Prior to discharge individual EPS determined the final programmed settings of the ICDs. During a mean follow-up of 13 +/- 1.4 months (range 2-20) the overall patient survival was 85.7%. No sudden arrhythmic or cardiac death occurred. Twenty of 21 patients (95%) received therapy by their device. In 14 patients (67%) antitachycardia pacing (ATP) was programmed "on," 13 of which was self-adaptative autodecremental mode. There were 247 VT episodes, 231 of which were subjected to ATP with 97% success and 3% acceleration or failure. Low energy shocks reverted all other VT episodes. VF episodes were successfully reverted by a single shock (93%), two shocks (6%), or three shocks (1%). We conclude that ATP therapy of VT is successful in the large majority of episodes with rare failures, and that VF episodes are generally terminated by a single ICD shock.
Four cases of fatal disseminated Scedosporium prolificans (inflatum) infection occurring in neutropenic patients are reported. Because of hospital renovation, the patients were cared for in a temporary hematologic facility. S. prolificans (inflatum) was isolated from blood cultures of these four patients, two of whom underwent full necropsy, and revealed abundant vegetative hyphae and ovoid conida with truncate bases in many organs. In vitro susceptibility testing of fungal strains showed all isolates to be resistant to amphotericin B, flucytosine, miconazole, ketoconazole, fluconazole, and itraconazole, with MICs greater than 16 micrograms/ml. The reported infections, two in each of two rooms, occurred over a period of 1 month, with very similar clinical outcomes. Circumstancial evidence suggested a nosocomial outbreak, but the environmental samples collected from the rooms, corridors, and adjacent areas did not yield S. prolificans (inflatum). Nevertheless, circumstantial evidence suggested a nosocomial outbreak of S. prolificans (inflatum) infection.
The lateral line system of lampreys includes photoreceptors distributed in the skin of the tail region. These are innervated by the trunk lateral line nerves, and the afferents terminate bilaterally in the medial octavolateral nucleus, crossing the midline through the cerebellar commissure. Stimulation of the dermal photoreceptors by tail illumination initiates locomotion. The present study was performed to characterize the response to illumination in larval and adult lampreys in detail and to elucidate the neuronal pathways responsible for the activation of locomotion. In both larval and adult quiescent lampreys, the response to unilateral illumination of the tail was found to consist of an initial turn followed by rectilinear swimming. The sign and magnitude of the turning angle were not correlated with the laterality of the optic stimulus. In mechanically restrained lampreys, spinalized at the level of segments 15­20, tail illumination evoked a complex motor response in the rostral part of the body, with switches between different patterns of coordination (turns in different directions, locomotion, and turns combined with locomotion). Thus, the response to tail illumination is not a simple reflex, but includes a behavioural choice. Reticulospinal neurones play a crucial role in the initiation of locomotion in lampreys. The response to unilateral tail illumination in rhombencephalic reticular cells was studied with extracellular single-unit recordings. It was found that neurones in the middle and posterior rhombencephalic reticular nuclei were activated bilaterally. Tonic activity or slow bursts (<0.5 Hz) were evoked, in some cases lasting up to 60 s after the stimulation. The response remained bilateral after transection of one lateral line nerve and the cerebellar commissure. Afferents from one side can thus activate reticulospinal cells on both sides through a pathway outside the cerebellar commissure. This bilateral activation of reticulospinal neurones is presumably responsible for the activation of spinal locomotor networks, without any directional bias to the left or the right side, and for the rectilinear swimming observed in behavioural experiments. In the caudal part of the termination area of the lateral line nerve afferents, neurones with contralateral projections were retrogradely stained with horseradish peroxidase. These neurones appear to be likely candidates for mediating the contralateral effects of the lateral line fibres.
Flow cytometry has rapidly expanded from basic research to clinical laboratories mainly due to its unique characteristics regarding cell analysis. Among the clinical uses of flow cytometry cancer represents one of the most relevant. Several applications of flow cytometry can currently be applied to the study of cancer, including the detection of tumour cell DNA aneuploidy, the analysis of tumour cell proliferation and the immunophenotyping of leukemias. Although standardized flow cytometry protocols for these applications are scanty, the clinical value has been clearly established. The presence of DNA aneuploidy and a high proportion of S-phase tumour cells have been associated with tumour malignancy and a poor prognosis. The immunophenotype of leukaemia is of great help both for the diagnosis and classification of chronic lymphoproliferative disorders and acute leukaemias, especially in acute lymphoblastic leukemia cases and the M0, M3-variant, M6 and M7 acute myeloblastic leukaemia subtypes. In addition, it allows the identification of relatively rare leukemia cases such as the biphenotypic and the Nk-cell lineage leukemias. The development of flow cytometry is continuously bringing new applications into the clinical laboratory in the area of cancer diagnosis.
In the past, studies on CD34+ cells have been based on the use of monoclonal antibodies conjugated with different fluorochromes that show different fluorescence intensity and yield variable results. Moreover, most of these studies have neither specifically focused on adult human BM samples nor have they used combinations to explore specifically the phenotype of myeloid committed CD34+ cells. The aim of the present study has been to characterize the normal human CD34+ precursor cells from adult BM in order to identify missing or extremely rare phenotypes that can be used for detecting minimal residual disease (MRD) in patients with AML. For this purpose we have utilized the fluorochrome conjugates that provide the most sensitive signals for identifying low antigenic expression, and the technique has been adapted to the characterization of cells present at very low frequencies. Normal human BM samples from 13 adult healthy volunteers have been analyzed using triple stainings at flow cytometry. The mean percentage of CD34+ cells detected was 0.72 +/- 0.33%; these cells displayed an heterogeneous light-scatter distribution. Most CD34+ cells coexpressed CD38 (96.7 +/- 5.7%), HLADR (81.6 +/- 14.0%), CD33 (84.7 +/- 18.3%), CD13 (84.6 +/- 16.2%) and CD71 antigens (65.5 +/- 9.1%). In addition, almost half of CD34+ cells were CD117+ (60 +/- 26.8%). Only a small proportion of CD34+ cells coexpressed CD4 (15.5 +/- 11.7%, CD36 (31.7 +/- 6.2%), CD61 (16.3 +/- 12.9%), CD41 (6.5 +/- 5.5%) or the lymphoid associated markers CD10 (18.6 +/- 11.8%) and CD19 (12.3 +/- 13.2%). Reactivity for the CD15 antigen was observed in a small population of CD34+HLADR+ cells (11.6 +/- 11.2%) although its intensity of expression was lower than that of the more mature granulocytic cells. No CD34+ cells displayed CD14, CD65, CD20, strong CD22, CD3 and CD56 antigens. Accordingly, most adult bone marrow CD34+ cells appeared to be committed to the myeloid lineage (CD13+/CD33+) and displayed an intermediate-to-large FSC/SSC while the lymphoid-committed CD34+ cells (CD19+, CD10+) were in a minority with low FSC/SSC values. By triple marker stainings several phenotypes of CD34+ precursor cells were found to be either undetectable or present at very low frequencies (< 1 x 10(-3)) in the normal human adult bone marrow. These data may be of great value for defining leukemia 'associated' phenotypes used to detect minimal residual disease in adult acute leukemia patients.
The aim of the present study was to analyze the incidence of AML cases displaying more than one blast cell subpopulation by immunophenotype at diagnosis, since, any of them, although minimal, can be responsible for the relapse. For this purpose we have prospectively investigated the immunophenotype of blast cells from 40 de novo AML patients at diagnosis with a large panel of monoclonal antibodies in double and triple staining combinations analyzed at flow cytometry. The discrimination between the different cell populations was based on: (1) the existence of aberrant phenotypes; (2) differences in light-scatter characteristics; and (3) the expression of differentiation-associated antigens (CD34, CD117, HLADR, CD33, CD15, CD14, CD11b and CD4). More than one blast cell subpopulation was identified in 34 patients (85%), two subpopulations in 12 patients (30%), three in three cases (7.7%), four in 13 patients (32.5%) and five populations in six cases (15%). The most common criteria for discrimination of blast cell subpopulations was based on the expression of maturation-associated antigens and, interestingly, the blast subpopulations defined by higher reactivity for myeloid differentiation-associated markers had a more mature FSC/SSC pattern. In 53% of the patients at least one of the subpopulations identified was minimal (< 10% of the total leukemic cells). Regarding the existence of aberrant phenotypes three situations were observed: (1) none of the subpopulations had antigenic aberrations (10 cases); (2) coexistence of normal and aberrant subpopulations (five cases); and (3) all the subpopulations displayed aberrant phenotypes (19 cases). In 17 of the 23 patients (74%) who had two or more blast cell subpopulations with phenotypic aberrations, at least one aberrant criteria was common to all the subpopulations; this criteria by itself would permit the simultaneous identification of all subpopulations in minimal residual disease (MRD) studies. In the remaining cases the investigation of MRD should be based on the phenotypic characteristics of each subpopulation.
The membrane phenotype of AML clonogenic cells (L-CFU) was analyzed in 19 AML patients using an in vitro culture technique after a complement-mediated lysis assay employing a panel of six monoclonal antibodies (McAb) -HLA-DR, FMC56 (CD9), FMC27 (CD9), CD14, CD15, CD41a-. Our results show that L-CFU has a heterogeneous but immature phenotype lacking on the expression of differentiation antigens (CD14, CD15, CD41a). In addition, we observed that the L-CFU phenotype is different from that of the whole blast cell population. Interestingly, L-CFU showed a higher expression of HLA-DR antigens with respect to their progeny. Upon analyzing whether the L-CFU phenotype was related to both the morphological and immunological features of AML blast cells, it was observed that, while there is no correlation with the FAB classification, there was a partial relationship between the immunological phenotype of AML blast cells and that of L-CFU. Accordingly, the more immature AML cases showed a more differentiated L-CFU phenotype (HLA-DR+, CD9+, FMC27+) when compared with cases with a more mature blast cell phenotype. These results suggest that those AML cases with a relatively immature myeloblastic phenotype may arise from a progenitor cell that has undergone partial differentiation and that is unable to acquire myeloid differentiation antigens, while those AML cases with mature blast cells might emerge from a very early L-CFU that has the capacity to undergo a greater degree of differentiation.
In order to investigate the duodenal motor response to continuous enteral feeding during critical illness, we recorded the duodenal contractions of 12 mechanically ventilated critically ill patients during a 4 h fasting period immediately followed by another 4 h period of continuous (100 kcal/h) nasogastric feeding with a polymeric diet. Duodenal motility was recorded by manometry (perfused catheter technique) and the migrating motor complexes (MMC) were identified by their activity front (period of high frequency, regular contractions). The incidence and the mean duration of activity fronts as well as the mean duration of the MMC (time interval separating two successive activity fronts) recorded during both periods were compared. The incidence of activity fronts (fasting: median: 2.5, interquartile range: 5.5; feeding: median: 2, interquartile range: 3.5), their duration (fasting: 6.2 +/- 1.6 min; feeding: 5.8 +/- 1.6 min), and the mean duration of the MMC (fasting: 50.9 +/- 24.7 min; feeding: 49.1 +/- 20.3 min) were similar during both periods. We conclude that in these patients, the fasting pattern of motility is not interrupted by the continuous nasogastric administration of a polymeric diet. Since the activity fronts of the MMCs are highly propulsive, we suggest that their abnormal persistence during feeding may play a role in the pathophysiology of unexplained diarrhoea in some critically ill patients.