Association between diabetes and esophageal cancer, independent of obesity, in the United States Veterans Affairs population.

In the past 30 years, the incidence of esophageal adenocarcinoma (EAC) has increased more rapidly than any other cancer in the United States. The prevalence of obesity and diabetes mellitus has drastically increased as well. We explored the potential association between obesity, diabetes mellitus, and EAC. By means of retrospective interrogation of an administrative database from fiscal year 2005-2009, we identified two cohorts. The cancer cohort was defined as patients with adenocarcinoma of the distal esophagus or gastric cardia. The comparison cohort contained patients with gastroesophageal reflux disorder (GERD; diagnosis coupled with a procedure code for fundoplication). Patient data, including demographic measures, diagnoses of obesity, diabetes mellitus, dyslipidemia, alcohol abuse, and nicotine dependence were examined. A logistic regression model identified risk factors for development of EAC. The sample included 2,836 patients identified as having either EAC (1,704) or fundoplication with GERD (1,132). Although slightly higher percentages of the benign cohort were obese, the cancer cohort had more diabetics (30.8% vs. 14.8%; chi-square = 94.5; P < 0.0001). In a logistic regression analysis adjusting for comorbidity and lifestyle factors, diagnosis of diabetes mellitus was significantly associated with esophageal cancer as opposed to GERD without cancer (OR = 2.2; 95% confidence interval [CI] 1.7-2.8). Nicotine dependence was also identified as a risk factor (OR = 1.7; 95% CI 1.4-2.0). We identified a potential association between diabetes mellitus and adenocarcinoma of the esophagus or gastric cardia. This association appears to be independent of obesity. Additionally, nicotine dependence was identified as a risk factor for EAC.

Biosynthesis of lipoprotein: location of nascent apoAI and apoB in the rough endoplasmic reticulum of chicken hepatocytes.

Our previous studies showed that in hepatic RER of young chickens, nascent apoAI is not associated with lipoprotein particles and only becomes part of these lipoprotein structures in the Golgi. In this study, we have used three different methodologies to determine the locations of apoAI and apoB in the RER and compared them to that of albumin. Immunoelectron microscopic examination of the RER cell fractions showed that both apoAI and apoB were associated only with the RER membrane whereas albumin was located both within the lumen and on the limiting membrane of the vesicles. To examine the possibility of membrane integration of nascent apoAI and apoB in the RER, we administered L-[3H]leucine to young chickens for 10 min, isolated RER, treated this cell fraction with buffers of varying pH, and measured the release of radioactive albumin, apoAI, and apoB. The majority of nascent apoAI (64%), nascent apoB (100%), and nascent albumin (97%) was released from RER vesicles at pH 11.2, suggesting that, like albumin, apolipoproteins are not integrated within the membrane. To determine if nascent apoproteins are exposed to the cytoplasmic surface, we administered L-[3H]leucine to young chickens and at various times isolated RER and Golgi cell fractions. Radioactive RER and Golgi cell fractions were treated with exogenous protease and the percent of nascent apoAI and apoB accessible to proteolysis was determined and compared to that of albumin. At 5, 10, and 20 min of labeling, 35-56% of nascent apoAI and 60-75% of apoB in RER were degraded, while albumin was refractive to this treatment. At all times both apolipoproteins and albumin present in Golgi cell fractions were protected from proteolysis. These biochemical and morphological findings indicate that apoAI and apoB are associated with the rough microsomal membrane and are partially exposed to the cytoplasmic surface at early stages of secretion. They may later enter the luminal side of the ER and, on entering the Golgi, form lipoprotein particles.

Identification of two regions in apolipoprotein B100 that are exposed on the cytosolic side of the endoplasmic reticulum membrane.

Protease protection assays of apolipoprotein B100 (apoB) in digitonin-permeabilized HepG2 cells indicated that multiple domains of apoB are exposed to the cytosol through an extensive portion of the secretory pathway. The intracellular orientation of apoB in the secretory pathway was confirmed by immunocytochemistry using antibodies recognizing specific domains of apoB in streptolysin-O (STP-O)- and saponin-permeabilized HepG2 cells. Lumenal epitopes on marker proteins in secretory pathway compartments (p63, p53, and galactosyltransferase) were not stained by antibodies in STP-O-treated cells, but were brightly stained in saponin-treated cells, confirming that internal membranes were not perforated in STP-O-treated cells. An anti-apoB peptide antibody (B4) recognizing amino acids 3221-3240 caused intense staining in close proximity to the nuclear membrane, and less intensely throughout the secretory pathway in STP-O-permeabilized cells. Staining with this antibody was similar in STP-O- and saponin-treated cells, indicating that this epitope in apoB is exposed to the cytosol at the site of apoB synthesis and throughout most of the remaining secretory pathway. Similar results indicating a cytosolic orientation were obtained with monoclonal antibody CC3.4, which recognizes amino acids 690-797 (79-91 kD) in apoB. Two polyclonal antibodies made to human LDL and two monoclonal antibodies recognizing amino acids 1878-2148 (D7.2) and 3214-3506 (B1B6) in apoB did not produce a strong reticular signal for apoB in STP-O-treated cells. The anti-LDL and B1B6 antibodies produced almost identical punctate patterns in STP-O-treated cells that overlapped with LAMP-1, a membrane marker for lysosomes. These observations suggest that the B1B6 epitope of apoB is exposed on the surface of the lysosome. The results identify two specific regions in apoB that are exposed to the cytosol in the secretory pathway.

Ubiquitin-proteasome-dependent degradation of apolipoprotein B100 in vitro.

Apolipoprotein B100 (apoB) is a large secretory protein that forms very low density lipoprotein in liver. An in vitro degradation assay was developed using rabbit reticulocyte (RR) lysate in order to investigate the mechanism of intracellular degradation of newly synthesized apoB by the ubiquitin-proteasome pathway. [3H]apoB, isolated from [3H]leucine pulsed/chased Hep G2 cells, was degraded 51% when incubated for 2 h at 37 degreesC in an assay mixture that included RR lysate (source of the ubiquitin conjugation system and proteasome) and an exogenous ATP regenerating system. ApoB degradation was ATP-dependent and degradation fragments were not observed suggesting that the very large apoB molecule was extensively degraded. ApoB degradation was decreased to 50% when potent proteasome inhibitors, clasto-lactacystin beta-lactone (10 microM) or MG-132 (50 microM), were added to the reaction mixture, but was not affected by the cysteine protease inhibitor, E-64, or the serine protease inhibitor, phenylmethylsulfonyl fluoride. ApoB degradation was inhibited by the mutant ubiquitin protein K48R and by ubiquitin aldehyde, an inhibitor of ubiquitin-protein isopeptidases. During incubation ubiquitination of apoB increased even as apoB was being degraded. These results suggest that in vitro degradation of apoB, a large secretory protein that is normally found in the endoplasmic reticulum (ER) lumen or associated with the ER membrane, was proteasome-dependent and involved both ubiquitination and deubiquitination steps.

Expression and secretion of chicken apolipoprotein AI in transfected COS cells.

A full-length chicken apolipoprotein A-I (apoAI) cDNA has been cloned into an expression vector, pRSVapoAI. This plasmid was transfected into a monkey kidney (COS-1) cell line in order to study apolipoprotein-lipid assembly. Chicken apoAI is the major apolipoprotein of chicken high-density lipoprotein (HDL), which is less complex in apolipoprotein content than the HDL of human plasma. The transient transfected COS-1 cells synthesized and secreted authentic plasma apoAI. Under serum-free medium conditions, COS cells secreted only proapoAI. A small portion (15%) of the secreted apoAI floated at a density 1.07-1.20 g/ml. Upon incubation with fetal bovine serum at 10 degrees C, a majority of the apoAI was recovered in the HDL density (1.06-1.20 g/ml) region. Secreted apoAI was labeled when transfected COS cells were incubated with [U-14C]palmitate, but the incorporation of radioactivity was not the result of fatty acid acylation through ester bond formation. These results indicate that heterologous COS-1 cells are capable of synthesizing and secreting apoAI, and that intracellular association of apoAI with lipids is not necessary for secretion.

Effect of atorvastatin on intracellular calcium uptake in coronary smooth muscle cells from diabetic pigs fed an atherogenic diet.

Intracellular Ca(2+) store loading has been shown to alter proliferation and apoptosis of several cell types. In addition, HMG-CoA reductase inhibitors (i.e. atorvastatin) are effective in treating diabetic dyslipidemic patients. Thus, we hypothesized that chronic atorvastatin treatment would prevent increased Ca(2+) uptake into intracellular Ca(2+) stores in vascular smooth muscle cells from diabetic dyslipidemic pigs. Male Yucatan pigs were divided into four groups for 20 weeks-- (1) low fat fed (control); (2) hyperlipidemic (F); (3) alloxan-induced diabetic dyslipidemic (DF); and (4) diabetic dyslipidemic pigs treated with atorvastatin (DFA). The F, DF, and DFA groups were fed a high fat/cholesterol diet. Cells were isolated from the coronary artery and the myoplasmic Ca(2+) (Ca(m)) response measured using single cell fura-2 imaging. The Ca(m) response to caffeine (5 mM to release Ca(2+) from the sarcoplasmic reticulum, SR) and ionomycin (10 microM; to release the total Ca(2+) store) was determined in either the presence of low Na (19Na; inhibits Na(+)-Ca(2+) exchange), thapsigargin (TSG; inhibits the SR Ca(2+) pump), and a 19Na+TSG solution. Low Na induced the uptake of Ca(2+) into both SR and non-SR Ca(2+) stores in the DF group, but not the DFA group. Furthermore, after depletion of the SR Ca(2+) store with TSG, 19Na evoked Ca(2+) uptake into non-SR Ca(2+) stores in all three groups except in the DFA group. In summary, this study demonstrates that atorvastatin prevents the enhanced uptake of Ca(2+) by SR and non-SR Ca(2+) stores in diabetic dyslipidemic pigs.

Effects of perfusate leucine concentration on the metabolism of valine by the isolated rat hindquarter.

Rates of oxidation of valine and release of alpha-ketoisovaleric acid by hindquarters from rats fed a 9% casein diet were measured at intervals over 90 minutes. The hindquarters were perfused with medium containing between 0.03 and 10 mmol/L L-leucine; concentrations of valine and isoleucine were kept constant at 0.2 and 0.1 mmol/L, respectively. The rate of oxidation of [1-14C]valine increased two to threefold when the perfusate contained 0.8 or 1.0 mmol/L leucine but was depressed by 50% when the leucine concentration was 10 mmol/L. The rate of release of alpha-ketoisovaleric acid from the hindquarter was affected little by perfusate leucine concentrations up to 1.0 mmol/L, but release was depressed when perfusate leucine concentration was increased to 10 mmol/L. The rate of release of alpha-ketoisocaproic acid increased with increasing perfusate leucine concentration, as did intracellular alpha-ketoisocaproic acid and leucine concentrations. These results indicate that valine oxidation by the isolated perfused hindquarter is stimulated by a high perfusate leucine concentration (1.0 mmol/L), suggesting that this response contributes to the depressed plasma and tissue valine pools of rats fed a high-leucine diet. An excessively high concentration of leucine (10 mmol/L) suppresses valine oxidation, presumably by competing with valine for transmination or transport.

Measuring Bacterial Production in Deep-Sea Sediments using 3H-Thymidine Incorporation: Ecological Significance.

Bacteria play a major role in the decomposition of organic matter arriving at the deep-sea floor, and hence there is a need to determine accurate rates of bacterial production associated with sediment particles. However, sediment-based procedures are not well defined and sampling deep-sea sediments is technically difficult, time consuming, and expensive, often only producing relatively small amounts of undisturbed sediment for analysis. We describe and test a small-scale method (requiring 0.25 ml sediment) for the examination of bacterial production in deep-sea calcium carbonate rich sediments. Time course experiments showed variation in the period of linear [3H]thymidine uptake between 1 and 3 hr depending on station depth. The average concentration of natural thymidine in deep-sea sediments was 0.61 nmol per 0.5 ml slurry sample. Isotope dilution was significant, ranging between 26 and 51%. There was substantial small-scale (0.2-1.0 m) variation in deep-sea benthic bacterial [3H]thymidine incorporation rates (39%). Deep-sea surficial sediment bacterial production (assuming zero isotope dilution due to its potential high variability) in surficial sediments of the deep NE Atlantic varied between 0.014 and 0.48 mg C g-1 d-1 (mean = 0.23 mg C g-1 d-1) over 3 locations of depths between 1,092 and 3,572 m and at 3 times. Bacterial biomass varied between 1.1 and 12 mg C g-1 (mean = 6.1 mg C g-1). Bacterial growth rate estimates in these deep-sea sediments varied between 0.003 and 0.13 d-1 (mean = 0.050 d-1) giving doubling times of 5.3-216 d (mean = 44.5 d); which are similar to those of bacteria inhabiting waters in the upper mixed layer (2-<40 m) of the water column (2.6-57.8 d). comparison with shallow and coastal sea sediments (0.13-116 d) indicates that deep-sea sediment bacteria in the NE Atlantic are able to grow at rates similar to those in shallow sediment systems given sufficient food. However, the range is broader for deep-sea sediment bacteria, which may indicate a more "feast" and "fast" life than their counterparts in shallower environments. waters >2,000 m cover 60% of the Earth's surface; thus bacterial production in deep-sea sediments must contribute an important fraction of oceanic and global bacterial production. It is therefore important to establish an accurate method of measuring bacterial production so that the full roles and controls of bacteria from this environment can be determined.

Use of cyclodextrin to deliver lipids and to modulate apolipoprotein B-100 production in HepG2 cells.

2-Hydroxypropyl-beta-cyclodextrin (cyclodextrin), cyclodextrin-solubilized oleate, and cyclodextrin-solubilized cholesterol were used to modulate proteolysis and secretion of newly-synthesized apolipoprotein B-100 (apoB) in HepG2 cells. Following cyclodextrin and lipid treatments, cells were pulse-labeled with [3H] leucine, and quantitative immunoprecipitation was used to measure apoB synthesis, apoB secreted into the medium, and the cellular content of undegraded apoB that was not secreted. Three-hour treatment with cyclodextrin-solubilized oleate (0.2 mM) increased secreted apoB from 4% (control cells) to 32% and cellular undegraded apoB from 15% (control cells to 64% of apoB synthesized, which is consistent with earlier studies using bovine serum albumin to complex exogenous oleate. Prolonged daily (4 d or more) administration of 0.5% (3.5 mM) cyclodextrin with medium containing 10% fetal bovine serum increased the secretion of nascent apoB from 5-10% (control) to 17-28% and cellular undegraded apoB from 15-20% (control) to 25-31% of apoB synthesized, respectively. Subsequent administration of cyclodextrin solubilized cholesterol (10-40 micrograms) for only 3 h reversed the cyclodextrin-mediated increase in apoB secretion. The application of 0.5% cyclodextrin to HepG2 cells can rapidly (within minutes) stimulate cholesterol efflux, and transiently (over a 1-2 d period) increase cholesterol synthesis. In the current studies, the cyclodextrin-mediated increase in cholesterol synthesis was not concurrent with the increase in apoB secretion. However, prolonged (15 d) administration of cyclodextrin was shown to increase the cellular free cholesterol concentration by 25-41%, reduce the cellular triglyceride concentration by 59%, and increase apoB secretion 3- to 4-fold, without affecting the cellular cholesteryl ester concentration. In comparison, 14-d treatment with cyclodextrin-solubilized cholesterol (20 micrograms/mL) followed by 1-d equilibration without cholesterol was shown to increase the cellular free cholesterol and cholesteryl ester concentrations by 76% and 10-fold, respectively, although apoB secretion was not affected. It is hypothesized that chronic daily administration of 0.5% cyclodextrin increased the cellular cholesterol concentration and flux in discrete putative regulatory compartments, which "shielded" nascent apoB from rapid proteolysis and facilitated apoB secretion. In conclusion, cyclodextrin was used independently and in combination with cholesterol or oleate to modulate apoB proteolysis and secretion. We speculate that subcellular changes in cholesterol concentration and flux may modulate apoB production in HepG2 cells.

Concurrent validity of the Koppitz Bender-Gestalt emotional indicators among women with mental retardation.

This study evaluated the concurrent validity of Koppitz' revised Bender-Gestalt Emotional Indicators among 44 women with mental retardation. The concurrent validity of the Emotional Indicator total score was not supported when compared with responses on two widely used and accepted screening inventories, the Reiss Screen and the Inventory for Client and Agency Planning.

Effects on plasma amino acid concentrations and hepatic branched-chain alpha-keto acid dehydrogenase activity of feeding rats diets containing 9 or 50% casein.

Plasma concentrations of amino acids and alpha-ketoisocaproate and alpha-keto-gamma- methiolbutyrate decarboxylation activities in livers of rats trained to eat 9 or 50% casein diets for 5 hours/day, were measured one-half hour before and one-half and 3 hours after the start of the feeding period. Decarboxylation of both alpha-ketoisocaproate and alpha-keto-gamma- methiolbutyrate by liver increased significantly within one-half hour after rats had ingested either the 9 or the 50% casein diet. Liver decarboxylation activity of rats fed the 50% casein diet was from two- to fivefold higher than that of rats fed the 9% casein diet. The greatest difference was observed when calcium, NAD and coenzyme A were included in the decarboxylation assay medium. Although the activity of the branched-chain alpha-keto acid dehydrogenase increased in response to food ingestion, plasma concentrations of branched-chain amino acids also increased greatly after the ingestion of food. The similarity in the responses of alpha-ketoisocaproate and alpha-keto-gamma- methiolbutyrate decarboxylation in rats fed diets differing in protein content and subjected to different feeding regimens allows us to suggest that the branched-chain alpha-keto acid dehydrogenase is responsible, in part, for the oxidative decarboxylation of the alpha-keto acid analog of methionine. J. Nutr . 114: 1025-1034, 1984.

Hepatic synthesis of lipoproteins and apolipoproteins.

We have attempted to review new information concerning the regulation of the secretion of three major apolipoproteins that are synthesized in the liver: apoB, apoA-I, and apoE. ApoB, which is a large protein involved in the transport of triglyceride and cholesterol from the liver to the peripheral tissues, appears not to be regulated on a short-term basis at the transcriptional level. Rather, once synthesized, this protein, which is unique in its intracellular transport in the secretory pathway, is subjected to post-translational regulation, which is dependent on the lipid status of the cell. Assembly of nascent apoB-containing LPs begins in the ER. If core lipids, whether triglyceride or cholesteryl ester, are limiting, then apoB will be rapidly degraded, most likely in the ER compartment. However, if one or both of the core lipids are available in adequate quantities, then apoB will be protected in the ER, and more apoB, in the form of an apoB-containing LP (whether VLDL or a smaller particle) will be secreted by the hepatocyte. Addition of surface lipids, mainly phospholipids or free cholesterol, probably occurs in the Golgi. A further mechanism that regulates the secretion of apoB-containing LPs may involve rapid reuptake of newly secreted particles. The regulation of the secretion of apoA-I by liver is very different from that of apoB. Although apoA-I is also synthesized on attached ribosomes and becomes contranslationally or post-translationally associated with the RER membrane, it is transported to the Golgi much more rapidly than apoB. In the Golgi nascent HDL particles are formed, but it is also likely that apoA-I is secreted by the hepatocyte in a lipid-poor form.(ABSTRACT TRUNCATED AT 250 WORDS)

Resource management progress of the program in the NHS in England.

1. HISTORY. The program began in 1986 as the Resource Management Initiative and had just six pilot sites. In 1989, Ministers decided to establish a national Resource Management Programme covering all general acute Hospitals in England with more than 250 beds--some 250-260 sites in all. A range of community units also embarked on a program of pilot projects aimed at testing the RM principles in those services. 2. ELEMENTS OF THE PROGRAM. A site joining the program was expected to submit a case based on readiness for inclusion, supported by an outline project plan before approval could be given. The plan encompassed a range of elements, but was individual to each unit; the philosophy being that each unit was being assisted to reach its own objectives within an overall framework. The elements of the framework were as follows: a) A vision of what was expected to be achieved by the project and the benefits being sought; b) A focus on improving the quality of patient care in the unit; c) Involving clinicians in the management process; d) The availability of clinical information to support decision-making; this included the hardware and software for Case-Mix Management and Nurse Management Systems, but also extended to coding, classifying, and grouping systems. e) A greater awareness of the financial implications of clinical decisions; f) A project management approach to implementation; g) An approach based on developing both the organization and its staff, with training. 3. THE KEY TO RM IMPLEMENTATION IS CULTURAL CHANGE AT THE UNIT LEVEL. While steps to achieve this change can be planned and driven forward via the project plan, the very nature of the project means that a more flexible and "soft systems" view of success is appropriate. Local ownership of the process is essential and can lead to a very specific view of "success." 4. BENEFITS. Demonstrating primary causality is difficult as eight years have elapsed since the program was started, and this has coincided with a period of radical change. However certain matters are beyond dispute: The vast majority of units have adopted one form or other of Clinical Directorate structure. Many clinical staff are formally engaged in the operational and general management process. Some RM sites are advantageous when it comes to negotiating with their purchaser organizations because they have better quality data on which to base the process. The use of Casemix Management and Nurse Management Systems is seen in some RM sites as improving the quality of patient care provided. RM has focused attention on clinical coding and grouping. RM has exposed the need to develop or reassess Information Strategies at unit level. RM has stimulated staff training and development at site level and has been instrumental in improving the quality of training facilities, resources, and materials that are available. RM is recognized as having had a catalytic effect on changes associated with the NHS Reforms. 5. CONCLUSION. Good quality services require well-managed and competent provider organizations. The RM program was designed to assist the improvement of provider unit management. There is general agreement that the principles of RM should be taken forward in the broader context of provider development, with a focus on quality as well as financial issues.

Regulation of hepatic secretion of apolipoprotein B-containing lipoproteins: information obtained from cultured liver cells.

A major theme of this review is that apoB secretion is regulated post-translationally, and that apoB secretion reacts rapidly to the current state of lipid metabolism in the cell. Therefore, as discussed by Fungwe et al. (122), the metabolism of triglyceride and of cholesteryl ester, in so far as both can be used as core lipids for apoB-containing LPs, are inextricably linked, and the shortage of one or both of these lipids could, by "allowing" increased intracellular degradation in the ER, inhibit the secretion of apoB. Another theme in this review is that the regulation of apoB secretion may be quite different in rat hepatocytes compared to cultured cells (HepG2) used as a model for human hepatocytes. Exogenous fatty acids appear to modulate the rate of apoB secretion in HepG2 cells, whereas they have only minimal effects on apoB secretion in rat hepatocytes or liver. Increased dietary cholesterol, on the other hand, appears to be an important modulator of apoB secretion in rats, but the evidence for effects of cholesterol on apoB secretion in HepG2 cells is less convincing. Finally, because HepG2 cells are an immortalized cell line, there could be many differences between these cells and human hepatocytes in vivo. Therefore, many of the results obtained with HepG2 cells should be corroborated in primary cultures of human hepatocytes. However, investigators utilizing primary human hepatocytes should be sure that the culture conditions are adequate to maintain the continued transcription of liver specific genes and to prevent the dedifferentiation of these cells in culture (85, 86).

Jehovah's Witnesses. The surgical/ethical challenge.

Physicians face a special challenge in treating Jehovah's Witnesses. Members of this faith have deep religious convictions against accepting homologous or autologous whole blood, packed RBCs, WBCs, or platelets. Many will allow the use of (non-blood-prime) heart-lung, dialysis, or similar equipment if the extracorporeal circulation is uninterrupted. Medical personnel need not be concerned about liability, for Witnesses will take adequate legal steps to relieve liability as to their informed refusal of blood. They accept nonblood replacement fluids. Using these and other meticulous techniques, physicians are performing major surgery of all types on adult and minor Witness patients. A standard of practice for such patients has thus developed that accords with the tenet of treating the "whole person'.