Matthew S. Loewenstein
Harvard University
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Featured researches published by Matthew S. Loewenstein.
Digestive Diseases and Sciences | 1978
Richard C. Gardner; Arthur E. Feinerman; Paul A. Kantrowitz; Stephen Gootblatt; Matthew S. Loewenstein; Norman Zamcheck
Fifty-seven patients with ulcerative colitis were followed 1–49 months (mean, 18 months) with serial CEA determinations during periods of remission, mild relapses, and severe relapses. Elevated CEA titers correlated with activity and possibly extent of disease: 12% of patients with proctitis, 47% of patients with left-sided colitis, and 60% of patients with transverse or universal colitis had elevated CEA titers during a flare. Moreover, 24% of patients with mild flares and 86% of patients with severe flares had elevated CEA titers. Ninety-two percent of patients with extensive disease and severe flares had elevated CEA titers. Elevated CEA titers were correlated with histologic findings in three patients. Inflammation of mucosa was demonstrated by colonoscopy and confirmed by biopsy in one patient with persistently elevated CEA titers during clinical remission. In two other patients with active disease whose CEA titers fell prior to colectomy, marked denudation of colonic mucosa was noted. In this study, a transiently elevated CEA titer indicated either clinically active ulcerative colitis or active inflammation of colonic mucosa.
European Journal of Cancer and Clinical Oncology | 1985
Eitan Scapa; Peter Thomas; Matthew S. Loewenstein; Norman Zamcheck
Fifty-one patients (16 with malignant extrahepatic biliary obstruction, ten with benign extrahepatic biliary obstruction, eight with alcoholic liver disease, five with viral hepatitis and 12 with liver metastases) and 19 adult healthy controls were studied with determinations of beta-N-acetyl hexosaminidase (a lysosomal enzyme which is cleared from the circulation by the Kupffer cells), carcinoembryonic antigen (CEA), serum bilirubin, alkaline-phosphatase and aspartate aminotransferase (AST). Both CEA and beta-NAH were elevated in each disease group. Elevated beta-NAH levels distinguished between benign and malignant extrahepatic biliary obstruction better than CEA levels. Beta-NAH levels for the malignant and the benign groups were 47.6 +/- 14.7 U/l and 23.0 +/- 4.7 U/l (mean +/- S.D.) respectively. The groups differed significantly (P less than 0.001). Plasma CEA levels for both groups were 18.7 +/- 38.9 and 7.2 +/- 3.3 ng/ml (mean +/- S.D.) respectively. Beta-NAH levels for the 19 normal controls were 15.8 +/- 3.5 U/l (mean +/- S.D.). Beta-NAH also was significantly elevated in patients with hepatic metastases (36.9 +/- 20.1 U/l). In 25 cancer patients with metastases other than in the liver beta-NAH levels (18.3 +/- 5.2) were not significantly elevated over the control group. It has potential value as a marker for non-CEA-producing liver metastases.
Digestive Diseases and Sciences | 1988
Eitan Scapa; Bentley H. Novis; Matthew S. Loewenstein; Peter Thomas; Norman Zamcheck
Abstractβ-N-Acetyl hexosaminidase (β-NAH), a lysosomal enzyme, was measured in the plasma of 15 patients with malignant extrahepatic biliary obstruction, 14 with benign extrahepatic obstruction, and 15 with long- standing benign intrahepatic cholestasis. β-NAH was correlated with total serum bile acid levels. The correlation was significant (P<0.05) for the malignant and benign intrahepatic obstructions but not for the benign extrahepatic obstructions. This is consistent with the idea that circulating high levels of bile acids in patients with long-standing biliary obstruction may cause damage to Kupffer cell membranes and to their receptors for β-N-acetyl hexosaminidase, impeding the clearance of the enzyme from the circulation resulting in elevated serum levels.
JAMA | 1975
Benjamin B. Lurie; Matthew S. Loewenstein; Norman Zamcheck
Gastroenterology | 1977
Matthew S. Loewenstein; Norman Zamcheck
Endocrinology | 1966
Leonard I. Kleinman; Matthew S. Loewenstein; Leon Goldstein
Journal of the National Cancer Institute | 1978
Robin A. Rittgers; Glenn Steele; Norman Zamcheck; Matthew S. Loewenstein; Paul H. Sugarbaker; Robert J. Mayer; Jacob J. Lokich; James Maltz; Richard E. Wilson
Journal of the National Cancer Institute | 1981
Matthew S. Loewenstein; Robin A. Rittgers; Herbert Z. Kupchik; Norman Zamcheck
Journal of the National Cancer Institute | 1980
Matthew S. Loewenstein; Prakash Rau; Robin A. Rittgers; Ballapuram G. Adhinarayanan; Herbert Z. Kupchik; Norman Zamcheck
American Journal of Clinical Pathology | 1985
Eitan Scapa; Darrow E. Haagensen; Walter Cantarow; Matthew S. Loewenstein; Peter Thomas; Norman Zamcheck