A mesenchymal malignant mesothelioma that changed from mixed type to purely sarcomatous type]

STUDY OBJECTIVE: To evaluate the long-term efficacy of laparoscopic Burch urethropexy. DESIGN: Pilot study. SETTING: Private practice. PATIENTS: Thirty-five consecutive women (average age 45.5 yrs, average parity 2.3, average weight 67.7 kg) treated for genuine stress incontinence between May 1992 and July 1994. INTERVENTIONS: Urethropexy was performed with curved needle suturing in 7 women, straight needle suturing in 5, and Stamey needle suturing in 23. Twenty-five (71.4%) patients had concomitant pelvic surgery. MEASUREMENTS AND MAIN RESULTS: Wilcoxon two-sample, chi2, and Fisher's exact tests were performed to determine which variables were significantly associated with surgical success. Average operating time was 190 minutes, hospitalization 24 hours, and catheterization 5 days. The cure rate of stress incontinence was 89% 3 months and 86% 1 year after surgery. At average follow-up of 34 months, only 68.6% of patients reported complete or almost complete cure, 11.4% were improved, and 20% were complete failures. The only operative variable approaching statistical significance for predicting surgical success was type of suture needle (p = 0.07), with the Stamey needle group having the highest cure rate. Women who were cured or almost cured had a significantly shorter follow-up than those who were improved or failures (p = 0.001). CONCLUSION: The success rate of laparoscopic Burch urethropexy compares with that of open Burch procedure at 1 year, but drops considerably thereafter.     

Small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features of the thoracic wall: a case report with histological, immunohistochemical and ultrastructural examinations

A case of small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features is presented. The tumor was encountered in a 32 year old Japanese woman with an initial presentation of palpable tumor in the left lateral region of the thorax. The resected tumor was a partially well encapsulated whitish medullary one and consisted of small round and spindle tumor cells, together with so-called rhabdoid cells in the small round cell area. Although pseudorosettes were often observed, true rosette formation could not be detected anywhere. Ultrastructurally, despite a histologic variety of tumor cells, most tumor cells possessed numerous mitochondria, some of which occasionally contained abnormal filamentous or crystalloid structures. Various amounts of microfilaments were present in most tumor cells and microtubules were present in a few. A minority of small round cells possessed a small number of neurosecretory granules, especially in short cytoplasmic processes. A positive immunoreaction for neuron specific enolase was found by immunohistochemical examination in several small round tumor cells and for neurofilaments in lesser numbers. Despite the lack of S-100 protein, MB2 was detected in both small round and spindle cells. On the basis of these findings, the tumor of the present case corresponds to malignant peripheral nerve sheath tumor with neuronal differentiation and oncocytic features.     

Reactivity of anti-AraC-resistant cell monoclonal antibody, YU-311, in formalin-fixed paraffin-embedded specimens of various hematopoietic disorders

YU-311 is a monoclonal antibody reacting with cytosine arabinoside (AraC)-resistant human leukemic cell line and identifies a 92 kDa membrane protein. We have examined YU-311 reactivity with various hematopoietic disorders by an immunohistochemical method and evaluated a correlation between YU-311 expression and refractoriness to chemotherapy, retrospectively. YU-311 reacted with AraC-resistant human leukemia cell lines, in which a 92 kDa membrane protein was identified by Western blotting, whereas drug-resistant cell lines to other than AraC failed to express YU-311 antigen. The frequency of YU-311 positivity was significantly increased in relapsed cases. Only five cases were positive for YU-311 at diagnosis and 24 cases at relapse. Unexpectedly, only eight cases of relapsed leukemia/lymphoma expressed YU-311 and P-glycoprotein simultaneously. Most of the YU-311-positive relapsed cases showed clinical refractoriness for chemotherapy and then failed to induct complete remission or relapsed at short periods with short disease-free duration. These findings indicate that YU-311 expression is closely associated with some aspects of drug resistance, especially with AraC resistance.     

Sarcomatoid carcinoma of the small intestine: histologic, immunohistochemical and ultrastructural features of three cases and its differential diagnosis

Three cases of sarcomatoid carcinoma of the small intestine are presented. One of them was found accidentally in the duodenum of a patient with a well differentiated adenocarcinoma and a malignant lymphoma that were limited to the stomach. The other two cases arose from the ileum. All of the tumors were whitish, soft and ulcerated with focal hemorrhage and necrosis and showed expansive growth. Each tumor consisted of a mixture of polygonal and spindle shaped anaplastic neoplastic cells arranged in sheet, short fascicular or haphazard fashion, with no finding suggesting epithelial differentiation. Special stains demonstrated intracellular mucin in only a small number of tumor cells in two cases, but not in the other case. Immunohistochemically, the tumor cells of two cases at both primary and metastatic sites showed a positive immunoreaction for cytokeratin and epithelial membrane antigen. In the other case, only a few tumor cells at the metastatic site, but not at the primary site, showed cytokeratin positivity. Various numbers of tumor cells positive for vimentin, alpha-1-antitrypsin (AAT), alpha-1-antichymotrypsin (ACT) and KP-1 were detected in each case. Ultrastructurally, some populations of tumor cells possessed various amounts of tonofilaments with a few intercellular connections between adjacent tumor cells. These cases should be classified as sarcomatoid carcinoma of the small intestine, despite partial or complete loss of epithelial features, and distinguished from the various sarcomas.     

Reactivity of antibody YU-311 in formalin-fixed, paraffin-embedded specimens of normal organs, non-hematopoietic tumors, and mast cell tumors

YU-311 is a monoclonal antibody that reacts with a human leukemia cell line resistant for cytosine arabinoside and that identifies a 92 kDa membrane protein. The reactivity of YU-311 in normal organs, various non-hematopoietic tumors and in mast cell tumors in formalin-fixed, paraffin-embedded specimens was examined using immunohistochemical methods. In normal organs, YU-311 reacted with fundic glands of the stomach, the intercalated duct of the pancreas, the distal portion and the loop of Henle of renal tubules and tissue mast cells. Benign neoplasms of various organs showed no immunoreaction with YU-311, except for mast cell tumors. Some types of malignant neoplasms were occasionally positive against YU-311, suggesting neoplasms arising from or differentiating along normal YU-311-positive counterparts. Some other types of malignancies were rarely positive for YU-311, although their normal counterparts showed no immunoreactivity with YU-311. None of the non-epithelial tumors reacted with YU-311, except for one case of malignant melanoma. In contrast, normal tissue mast cells and their related tumors, such as urticaria pigmentosa or solitary mastocytoma, were constantly positive for YU-311. None of the non-hematopoietic human tumor cell lines examined in the present study was reactive with YU-311. These findings indicate that YU-311 is a good marker of some types of tumors and mast cell tumors and that an aberrant expression of YU-311 rarely occurs.     

Model-based and actual independence for fairness-aware classification

The goal of fairness-aware classification is to categorize data while taking into account potential issues of fairness, discrimination, neutrality, and/or independence. For example, when applying data mining technologies to university admissions, admission criteria must be non-discriminatory and fair with regard to sensitive features, such as gender or race. In this context, such fairness can be formalized as statistical independence between classification results and sensitive features. The main purpose of this paper is to analyze this formal fairness in order to achieve better trade-offs between fairness and prediction accuracy, which is important for applying fairness-aware classifiers in practical use. We focus on a fairness-aware classifier, Calders and Verwer’s two-naive-Bayes (CV2NB) method, which has been shown to be superior to other classifiers in terms of fairness. We hypothesize that this superiority is due to the difference in types of independence. That is, because CV2NB achieves actual independence, rather than satisfying model-based independence like the other classifiers, it can account for model bias and a deterministic decision rule. We empirically validate this hypothesis by modifying two fairness-aware classifiers, a prejudice remover method and a reject option-based classification (ROC) method, so as to satisfy actual independence. The fairness of these two modified methods was drastically improved, showing the importance of maintaining actual independence, rather than model-based independence. We additionally extend an approach adopted in the ROC method so as to make it applicable to classifiers other than those with generative models, such as SVMs.     

Learning from Cluster Examples

Learning from cluster examples (LCE) is a hybrid task combining features of two common grouping tasks: learning from examples and clustering. In LCE, each training example is a partition of objects. The task is then to learn from a training set, a rule for partitioning unseen object sets. A general method for learning such partitioning rules is useful in any situation where explicit algorithms for deriving partitions are hard to formalize, while individual examples of correct partitions are easy to specify. In the past, clustering techniques have been applied to such problems, despite being essentially unsuited to the task. We present a technique that has qualitative advantages over standard clustering approaches. We demonstrate these advantages by applying our method to problems in two domains; one with dot patterns and one with more realistic vector-data images.     

Case of familial amyloid polyneuropathy discovered at the development of hematemesis

In a retrospective study we analyzed clinical features and their prognostic significance in 72 patients with onset of multiple sclerosis by the age of 21 years. In juvenile multiple sclerosis disease progression does not depend on age of onset, severity of neurologic involvement, or polysymptomatic or monosymptomatic involvement at presentation.     

Propionitrile formation from ethene and ammonia over Rh/Y-zeolite

The Rh/Y-zeolite has been found to be more active and selective for propionitrile formation from ethene and ammonia than other transition metal supported Y-zeolites. A reaction between ethene and hydrogen cyanide has been proposed as a reaction route for propionitrile formation.     

Resistance to apoptosis induced by serum depletion and all-trans retinoic acid in drug-resistant leukemic cell lines

The relation between resistance to anticancer drugs and resistance to apoptosis has been investigated in the human leukemic cell line(KY-821) and its drug-resistant sublines. Under serum depletion conditions, drug-resistant cell lines showed apoptotic resistance when compared with the parental cell line. Drug resistant cell lines also showed resistance to apoptosis when treated with all-trans retinoic acid. DNA fragmentation was low in drug resistant cell lines under both stimulations. Flowcytometry analysis did not show any alterations of the Fas antigen, p53, bcl-2 and c-myc protein expression toward inhibition of apoptotic response in drug-resistant sublines. These results indicate that drug-resistant leukemic cells still show resistance to apoptosis-inducing stimulation such as poor nutrition and differentiation-inducing agents.