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Wiley W Souba

Publications and source records attributed to Wiley W Souba.

At least 37 records · Page 2Linked to original sources
PubMed2003

Sources of error in delayed payment of physician claims.

BACKGROUND AND OBJECTIVES: Our objectives were to determine the distribution of errors and estimate the magnitude of the burden of delayed payments in a large physician group practice. METHODS: A 25% random sample (n=775) was taken from all billed records of a physician group practice in the Pacific Northwest that were delayed 6 months or more as of June 30, 2001. The source and specific reasons for payment delays, as well as the amount of each unpaid invoice, were determined by electronic documentation or telephone calls to the payor. Analysis of variance was used to determine whether the amount of the invoice was associated with the source and reason of error. RESULTS: The source of delayed payments due to provider, payor, patient, and technical error were 36.1%, 28.1%, 14.5%, and 21.3%, respectively. The most-frequent reasons for delayed payment were that the provider incorrectly set up the account (15.2%), the provider did not follow up on denial (12.9%), and the payor incorrectly processed the invoice (11.6%). Analysis of variance suggested that the invoice amount was not significantly associated with the source but was significantly different across reasons for delayed payment. The potential financial impact of earlier recovery of payment was $262,270. CONCLUSIONS: In these data, provider and payor errors accounted for almost two thirds of delayed payments. The most promising avenue for providers to reduce delayed payments is by reducing their own errors. Eliminating the two most common errors would result in a more timely recovery of nearly $70,000 in revenues.

Insurance, Health, Reimbursement↗
PubMed2002

Posttranslational alanine trans-stimulation of zwitterionic amino acid transport systems in human intestinal Caco-2 cells.

BACKGROUND: Neutral dietary amino acids, such as alanine, are transported across the gut lumen by both Na(+)-dependent (System B) and Na(+)-independent (System L) carriers, but the nature of the acute phase of substrate-induced uptake is unknown. This study examined the effects of acute amino acid substrate exposure on the rapid modulation of apical membrane alanine transport in cultured human intestinal cells. METHODS: System B and System L transport activity kinetics, as well as ATB(0) mRNA levels, were measured in confluent Caco-2 monolayers treated with various metabolic agents during short-term and extended time periods. RESULTS: Depleting the incubation medium of alanine attenuated both System B and System L uptake activities within 30 mins, with a complete return to baseline values within 3 h. Extracellular alanine added to depleted Caco-2 cells rapidly (within 5 min) increased alanine transport activities. Kinetic analysis showed that acute alanine exposure increased both K(m) and V(max) of each transport system, indicative of a trans-stimulation effect. Augmenting intracellular alanine levels using the cytosolic alanine aminotransferase inhibitor, aminooxyacetic acid, increased alanine uptake activity. Acute exposure to other substrates of Systems B and L also increased the uptake of alanine, while nonsubstrates did not affect alanine uptake. Cycloheximide or actinomycin did not affect substrate acute activation of System B, and the steady-state level of ATB(0) mRNA was not altered by amino acid exposure. CONCLUSION: Increasing alanine availability to intestinal cells, by either exogenous substrate exposure or inhibition of intracellular catabolism, acutely and reversibly increases apical membrane alanine transport activity via a posttranslation trans-stimulation mechanism.

Alanine↗
PubMed2002

Protein kinase C activation of intestinal glutamine transport is mediated by mitogen-activated protein kinases.

BACKGROUND: Glutamine is essential for the preservation of intestinal structure and function and its uptake by the bowel is augmented during catabolic states. However, the signal transduction pathways implicated in brush border glutamine transport have not been examined. The aim of this study was to investigate the intracellular signaling pathways involved in the regulation of accelerated intestinal glutamine transport. Our hypothesis was that the activation of intestinal glutamine transport involves protein kinase C (PKC) and is mediated by mitogen-activated protein kinases (MAPKs). METHODS: [3H]L-Glutamine (50 microM) transport activity and mRNA levels for the intestinal glutamine transporter ATB(0) were measured in intestinal epithelial Caco-2 cells. Confluent cells were treated with phorbol ester (PMA, 0-10 microM), the MAPK MEK inhibitor PD 98059 (0-100 microM), actinomycin (0-0.1 microM), MAPK p38 inhibitor SB 203580 (0-10 microM), protein kinase C inhibitor chelerythrine chloride (0-6.6 microM), or cycloheximide (0-10 microM) for 24 h. Data were analyzed by ANOVA with significance set at P < 0.05. RESULTS: Phorbol ester treatment increased intestinal System B glutamine transport activity by 75%, an increase that was blocked individually by PD 98059, chelerythrine chloride, actinomycin, and cycloheximide, but not SB 203580, an effect first noted at 6 h. The resulting activity increase was consistent with de novo synthesis of transporter units and enhanced expression of transporter gene ATB(0) as indicated by a threefold increase of ATB(0) mRNA levels in PMA-treated cells. CONCLUSIONS: Activation of glutamine transport in Caco-2 cells by phorbol ester occurs via signaling pathways that lead to transcription of the glutamine transporter gene. PKC and mitogen-activate protein kinase MEK are key intracellular mediators involved in this signal transduction cascade.

Amino Acid Transport System ASC↗
PubMed2002

Leadership in action.

Explore the source record for details and available documents.

Academic Medical Centers↗
PubMed2002

Academic medicine and the search for meaning and purpose.

The transformation of the health care industry into a marketplace governed by commercialism and free competition challenges the doctrine of medicine as a profession valuing service to the patient above financial reward. Many physicians have become disenchanted with their ability to serve as advocates for and provide care to their patients. Financial success, the measure of the marketplace, has become the dominant standard of measurement or "value" for most academic medical centers (AMCs). Many doctors report their work is less fulfilling. As a result, all three social missions-patient care, teaching, and research-are in jeopardy. The growth of modernism, preeminence of biomedical research, and dominance of a market-driven clinical enterprise will continue to pose challenges to the health care system in the United States. However, AMCs can provide the leadership and serve as the ambassadors through which the health care system can be renewed with a sense of direction and purpose. Renewal must begin with more open discourse about what we value in health care and what kind of medical profession we want to have, to include addressing questions such as: What does it mean to be an academic physician? What gives my work meaning and purpose? This kind of dialogue could easily be built into the medical students' curricula and residency training programs, with the faculty taking the lead.

Faculty, Medical↗
PubMed2002

Molecular and functional analysis of glutamine uptake in human hepatoma and liver-derived cells.

Human hepatoma cells take up glutamine at rates severalfold faster than the system N-mediated transport rates observed in normal human hepatocytes. Amino acid inhibition, kinetic, Northern blotting, RT-PCR, and restriction enzyme analyses collectively identified the transporter responsible in six human hepatoma cell lines as amino acid transporter B(0) (ATB(0)), the human ortholog of rodent ASCT2. The majority of glutamine uptake in liver fibroblasts and an immortalized human liver epithelial cell line (THLE-5B) was also mediated by ATB(0). The 2.9-kb ATB(0) mRNA was equally expressed in all cell lines, whereas expression of the system A transporters ATA2 and ATA3 was variable. In contrast, the system N isoforms (SN1 and SN2) were expressed only in well-differentiated hepatomas. ATB(0) mRNA was also expressed in cirrhotic liver and adult and pediatric liver cancer biopsies but was not detectable in isolated human hepatocytes or fetal liver. Although the growth of all hepatomas was glutamine dependent, competitive inhibition of ATB(0)-mediated glutamine uptake blocked proliferation only in poorly differentiated cells lacking SN1 or SN2 expression and exhibiting low glutamine synthetase mRNA levels.

Amino Acid Transport System ASC↗