Human triacylglycerol-rich lipoprotein subfractions as substrates for lipoprotein lipase.

In order to test the hypothesis that lipoprotein lipase (LPL) acts preferentially on larger lipoprotein particles, we determined the susceptibility of triacylglycerol-rich lipoprotein (TRL) subfractions to hydrolysis by LPL in vitro. Chylomicrons (Sf > 400), very low density lipoproteins (VLDL)1 (Sf 60-400) and VLDL2 (Sf 20-60) were isolated from six subjects with a range of plasma-triacylglycerol (TAG) concentrations following an overnight fast and for up to 6 h after the consumption of a mixed meal (41% fat). The percent of TRL-TAG hydrolysed by LPL in subfractions isolated following overnight fast was VLDL1 > VLDL2 (46.

Impaired postprandial clearance of triacylglycerol-rich lipoproteins in adipose tissue in obese subjects.

Adipose tissue is an important site of clearance of circulating triacylglycerol (TAG), especially in the postprandial period. Postprandial lipemia is usually increased in obesity. We studied the extraction of TAG from plasma and TAG-rich lipoproteins (TRLs) in subcutaneous adipose tissue in 11 control and 8 obese subjects before and after a mixed meal.

Catecholamine interference with enzymatic determination of nonesterified fatty acids in two commercially available test kits.

We present evidence that catecholamines, which are commonly used to stimulate lipolysis in adipose tissue in vitro, interfere with the enzymatic determination of non-esterified fatty acid (NEFA) in two commercially available kits. Measurement of a 100 mumol/L standard with the Wako "NEFA C" test kit was 60% inhibited by 100 mumol/L norepinephrine and was completely inhibited by 100 mumol/L isoproterenol or by 1 mmol/L norepinephrine or epinephrine. Measurement with the Boehringer Mannheim "Free Fatty acids, Half-micro test" was completely inhibited by 100 mumol/L norepinephrine and was also affected by concentrations as low as 0.

Classification of ductal carcinoma in situ by image analysis of calcifications from digital mammograms.

There is evidence to suggest that non-comedo cases of ductal carcinoma in situ (DCIS) may have a lower risk of progressing to invasive disease than comedo DCIS and may be managed with less radical treatment. Most cases of DCIS present as calcifications on the mammogram and, due to differences in the tumour architecture, comedo calcifications often have a characteristic linear or branching appearance. In this study, computer methods were developed to identify the comedo cases using the imaging features of individual calcifications and of calcification clusters.

Coordinated regulation of hormone-sensitive lipase and lipoprotein lipase in human adipose tissue in vivo: implications for the control of fat storage and fat mobilization.

The enzymes lipoprotein lipase (LPL, EC 3.1.1.

Identification of bone marrow micrometastases in patients with prostate cancer.

Background: Thirty percent of patients with clinically localized prostate cancer and a negative bone scan will experience relapse with recurrent disease despite treatment of the primary tumor. This may be due to the presence of metastatic prostate cancer cells at the time of treatment undetected by conventional methods, radionucleotide bone scan, and serum prostatic specific antigen blood test.

Methods: The authors used polymerase chain reaction (PCR) amplification of the prostate-specific antigen (PSA) mRNA sequence reverse-transcriptase PCR (RTPCR) and immunohistochemistry using a PSA antibody to identify metastatic prostate cancer cells in the bone marrow of patients with prostate cancer.

Urticaria pigmentosa--response to topical steroids.

A case of adult-onset urticaria pigmentosa is presented, in which the eruption cleared following the application of potent topical corticosteroids. Remission could be maintained by intermittent topical treatment. Topical steroids would appear to provide a simple, cheap and effective alternative to standard therapies.

Nodular hyperplasia surrounding fibrolamellar carcinoma: a zone of arterialized liver parenchyma.

We report a case of acetaminophen-induced liver necrosis in a 14-year-old girl. At autopsy, a 9 cm subcapsular nodule was present in the right lobe of the liver which showed distinct zonation: a central greyish white area of fibrolamellar carcinoma with a peripheral fleshy, tan-coloured rim ranging from 1 to 2 cm in thickness. This peripheral zone consisted of nodular, hyperplastic parenchyma resembling the changes seen in focal nodular hyperplasia, and stood out from the adjacent necrotic parenchyma.

Fasting plasma triacylglycerol concentrations predict adverse changes in lipoprotein metabolism after a normal meal.

The changes in lipoprotein metabolism which follow the ingestion of a large fat load have been well described. The hypothesis was tested that similar changes in lipoprotein metabolism would occur after a relatively normal meal. Plasma and lipoprotein triacylglycerol, cholesterol and apolipoprotein concentrations were determined in twenty subjects (ten female) given a mixed meal containing approximately one-third of the daily intake of major nutrients in the typical Western diet.

Radiation dose associated with spiral computed tomography.

Spiral computed tomography (CT) has recently become available as a practical diagnostic tool; its introduction has created the need for a comprehensive understanding of the magnitude and distribution of the radiation dose to the patient. Dose distributions for conventional and spiral CT were measured with thermoluminescent dosimeters loaded in standard phantoms and then compared to determine the validity of using standard dose descriptors for assessing the dose delivered during spiral CT. Two dose descriptors applied to conventional CT, the CT dose index and the multiple-scan average dose, were found to be adequate for quantifying the dose delivered by spiral CT.

Commonality of the gene programs induced by effectors of apoptosis in androgen-dependent and -independent prostate cells.

Prostate tissue is composed of both androgen-dependent and -independent cells. To identify the gene program induced by effectors of apoptosis in both of these cell types, we performed differential hybridization on a complementary DNA library prepared from an androgen-independent prostate cancer cell line, AT-3, exposed to ionomycin. Five distinct complementary DNAs representing ionomycin-inducible genes, designated prostate apoptosis response (par) -1, -2, -3, -4, and -5, were identified.

Sensitivity of immunohistochemistry and polymerase chain reaction in detecting prostate cancer cells in bone marrow.

Occult micrometastases detected by immunohistochemistry have prognostic significance in patients with localized breast cancer. To determine the usefulness of this technique and of polymerase chain reaction in detecting occult prostate cancer, we evaluated the sensitivity and specificity of immunohistochemistry and polymerase chain reaction amplification of mRNA to detect prostate cancer cells in bone marrow samples. We used cells from an established prostate cancer cell line (LNCAP) mixed with lymphocytes at various dilutions from 10(5) cancer cells in 10(6) lymphocytes to 1:10(6).

Regulation of fatty acid movement in human adipose tissue in the postabsorptive-to-postprandial transition.

There is net outward flow of fatty acids from adipose tissue in the fasted state but net inward flow and storage in the postprandial state. We investigated how this is regulated. Arteriovenous differences were measured across a subcutaneous adipose depot in six normal subjects before and for 5 h after a meal containing 80 g fat and 80 g carbohydrate.

Forearm substrate utilization during exercise after a meal containing both fat and carbohydrate.

1. Whilst the provision of exogenous carbohydrate has been shown to be beneficial to endurance exercise performance, little attention has been paid to the possibility of dietary manipulation of the availability of fat. 2.

Immediate metabolic availability of dietary fat in combination with carbohydrate.

We tested the hypothesis that when fat is ingested in combination with carbohydrate, direct release of fatty acids into the plasma may occur. Eight normal subjects ingested two meals: high-fat (80 g fat, 80 g carbohydrate, and 18 g protein) and low-fat (< 1 g fat, otherwise closely matched). Over the subsequent 6 h, net fat oxidation was greater after the high-fat meal (20.

Subcutaneous adipose tissue metabolism studied by local catheterization.

Adipose tissue is a metabolically active tissue which plays a key role in regulating the concentrations of circulating lipid fuels. In recent years, two new techniques have become available for the study of human adipose tissue metabolism in vivo: microdialysis, and catheterization of the venous drainage from the subcutaneous abdominal adipose tissue. Blood obtained by the latter method shows all the characteristics expected of adipose tissue drainage.

Modulation of B lymphocyte differentiation by calcitonin gene-related peptide (CGRP). II. Inhibition of LPS-induced kappa light chain expression by CGRP.

The presence of calcitonin gene-related peptide (CGRP) in nerve endings in lymphoid organs, around blood vessels, and in bone marrow suggests that it might influence the function and differentiation of lymphoid cells. Previous studies identified specific CGRP receptors on mature T and B lymphocytes and on 70Z/3 pre-B cells. In these studies, it was found that CGRP stimulated a rapid, prolonged elevation of cAMP with in 70Z/3 cells with an ED50 of approximately 20 fM.

Modulation of B lymphocyte differentiation by calcitonin gene-related peptide (CGRP). I. Characterization of high-affinity CGRP receptors on murine 70Z/3 cells.

Calcitonin gene-related peptide (CGRP) is a 37-amino acid neuropeptide found in both peripheral and central neurons and in certain endocrine tissues. Previous studies have identified specific high-affinity CGRP receptors on normal T and B cells and have described modulatory effects of CGRP on freshly isolated lymphocytes. In these studies several lymphocyte cell lines were screened for 125I-CGRP binding.

Isolation and characterization of microsatellites from the canine genome.

Microsatellite sequences comprising (dC-dA)n.(dG-dT)n repeats have been isolated from canine libraries and sequenced. Oligonucleotide primers have been synthesized to the microsatellite flanking sequences and used in the polymerase chain reaction to amplify those loci from genomic DNA.

Mono-, di- and triacylglycerol concentrations in human plasma: effects of heparin injection and of a high-fat meal.

A sensitive method has been developed to measure specific mono-, di- and triacylglycerol concentrations in human plasma, using thin-layer chromatography and enzymatic assay. The levels of partial acylglycerols in human plasma from fasting subjects were lower than previous reports had suggested and amounted to less than 3% of the total acylglycerols. After heparin injection the plasma monoacylglycerol concentration increased markedly (P < 0.

Periprandial regulation of lipid metabolism in insulin-treated diabetes mellitus.

We have examined the regulation of lipid and glucose metabolism in the postabsorptive and postprandial states in six subjects with insulin-treated diabetes mellitus, and compared them with eight nondiabetic subjects. Blood or plasma concentrations of metabolites and fluxes across forearm and subcutaneous adipose tissue were studied after an overnight fast and for 6 hours after a mixed meal (3.1 MJ, 41% from fat).