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Recent studies in hepatocytes indicate that Na(+)-coupled HCO3- transport contributes importantly to regulation of intracellular pH and membrane HCO3- transport. However, the direction of net coupled Na+ and HCO3- movement and the effect of HCO3- on Na+ turnover and Na+/K+ pump activity are not known. In these studies, the effect of HCO3- on Na+ influx and turnover were measured in primary rat hepatocyte cultures with 22Na+, and [Na+]i was measured in single hepatocytes using the Na(+)-sensitive fluorochrome SBFI. Na+/K+ pump activity was measured in intact perfused rat liver and hepatocyte monolayers as Na(+)-dependent or ouabain-suppressible 86Rb uptake, and was measured in single hepatocytes as the effect of transient pump inhibition by removal of extracellular K+ on membrane potential difference (PD) and [Na+]i. In hepatocyte monolayers, HCO3- increased 22Na+ entry and turnover rates by 50-65%, without measurably altering 22Na+ pool size or cell volume, and HCO3- also increased Na+/K+ pump activity by 70%. In single cells, exposure to HCO3- produced an abrupt and sustained rise in [Na+]i from approximately 8 to 12 mM. Na+/K+ pump activity assessed in single cells by PD excursions during transient K+ removal increased congruent to 2.5-fold in the presence of HCO3-, and the rise in [Na+]i produced by inhibition of the Na+/K+ pump was similarly increased congruent to 2.5-fold in the presence of HCO3-. In intact perfused rat liver, HCO3- increased both Na+/K+ pump activity and O2 consumption. These findings indicate that, in hepatocytes, net coupled Na+ and HCO3- movement is inward and represents a major determinant of Na+ influx and Na+/K+ pump activity. About half of hepatic Na+/K+ pump activity appears dedicated to recycling Na+ entering in conjunction with HCO3- to maintain [Na+]i within the physiologic range. [ABSTRACT FROM AUTHOR]

Purpose: To compare access to specific procedural therapies across insurance types for patients with American Joint Commission on Cancer (AJCC) Stage I or II hepatocellular carcinoma (HCC)., Materials and Methods: Using the National Cancer Database, patients diagnosed with Stage I or II HCC between 2004 and 2019 were identified. Parametric and nonparametric testing was used to compare the rates of procedural modalities and time to therapy across insurance types. Univariate and multivariate logistic regression analyses were used to identify the likelihood of receiving specific procedural therapy based on insurance status., Results: In total, 105,703 patients with AJCC Stage I or II HCC were identified. The rates of ablative therapy were similar across insurance types (18.1% total, 17.2% private insurance, 15.3% uninsured, 18.1% Medicaid, and 18.8% Medicare). In the logistic regression analysis, patients with private insurance were more likely to receive a transplant or undergo resection or procedural therapy of any kind. Patients with Medicare insurance were more likely to undergo ablation (odds ratio, 1.11; 95% confidence interval, 1.07-1.15; P < .001) than those with private insurance., Conclusions: Patients with private insurance were more likely to receive most forms of procedural therapy for early-stage HCC, with the notable exception of ablative therapy, which patients with Medicare were slightly more likely to receive., (Copyright © 2023 SIR. Published by Elsevier Inc. All rights reserved.)

Background: Studies describing the incidence of Crohn's disease (CD) and ulcerative colitis (UC) are uncommon in the United States. We sought to determine the incidence of CD and UC in the state of Rhode Island., Methods: The Ocean State Crohn's and Colitis Area Registry is a state-based inception cohort of patients newly diagnosed with inflammatory bowel disease (IBD) in Rhode Island. To confirm a diagnosis of CD, UC, or IBD unclassified (IBDU), the National Institute of Diabetes and Digestive and Kidney Diseases IBD Genetics Consortium criteria were applied in a review of medical records from gastroenterology practices located in the state of Rhode Island and adjacent to the Rhode Island border in Massachusetts and Connecticut. Using population-based data, we determined the statewide incidence of IBD in Rhode Island from 2008 to 2010., Results: A total of 971 Rhode Island residents were diagnosed with IBD, including 444 with CD, 486 with UC, and 41 with IBD unclassified from 2008 to 2010. The overall age- and sex-adjusted IBD incidence was 30.2 (95% confidence interval, 28.3-32.1) per 100,000 persons in this time frame with 13.9, 15.1, and 1.3 per 100,000 diagnosed with CD, UC, and IBD unclassified, respectively. Of the total incident cases in Rhode Island, 30% (n = 291) were enrolled in Ocean State Crohn's and Colitis Area Registry for follow-up., Conclusions: The incidence of IBD in Rhode Island is higher than that previously reported by other population-based cohorts in the United States. Prospective follow-up of individuals enrolled in the community-based Ocean State Crohn's and Colitis Area Registry cohort is ongoing.

Background: Despite the fact that the inflammatory bowel diseases (IBD) and their treatments may affect physical appearance, the effect of IBD on body image is poorly understood. The aims of this study were to determine whether body image dissatisfaction (BID) changes over time in patients with IBD and to examine the demographic and disease-related variables associated with decreased body image., Methods: Adults aged 18 and above in the Ocean State Crohn's and Colitis Area Registry with at least 2 years of follow-up were eligible for this study. All patients were enrolled within 6 months of IBD diagnosis and followed prospectively. BID was assessed using a modified version of the Adapted Satisfaction With Appearance questionnaire. Total Adapted Satisfaction With Appearance scores and 2 subscores were calculated. To assess for changes over time, general linear models for correlated data were used for continuous outcomes, and generalized estimating equations were used for discrete outcomes., Results: Two hundred seventy-four patients were studied. BID was found to be stable over time among men and women with IBD despite overall improvements in disease activity. No differences were found in BID according to IBD subtype. Female gender, greater disease activity, higher symptom burden, longer duration of steroid use, dermatologic and musculoskeletal manifestations of IBD, and ileocolonic disease location among patients with Crohn's disease were associated with greater BID. Greater BID was associated with lower health-related quality of life., Conclusions: BID remains stable in an incident cohort of IBD despite improved disease activity and is associated with lower health-related quality of life.

Background: The effect of the inflammatory bowel diseases (IBD) on menstrual function is largely unknown. The aims of this study were to determine whether changes in menstrual function occur in the year before IBD diagnosis or in the initial years after diagnosis., Methods: Women aged 18 years and older in the Ocean State Crohn's and Colitis Area Registry with at least 2 years of follow-up were eligible for this study. All patients were enrolled within 6 months of IBD diagnosis and followed prospectively. Menstrual cycle characteristics were retrospectively assessed. To assess for changes over time, general linear models for correlated data were used for continuous outcomes, and generalized estimating equations were used for discrete outcomes., Results: One hundred twenty-one patients were studied. Twenty-five percent of patients experienced a change in cycle interval in the year before IBD diagnosis and 21% experienced a change in the duration of flow. Among women with dysmenorrhea, 40% experienced a change in the intensity of their menstrual pain and 31% experienced a change in its duration. Overall cycle regularity increased over time. Quality of life was significantly lower in women without regular cycles across all time points., Conclusions: Changes in menstrual function occur frequently in the year before IBD diagnosis; therefore, screening for menstrual irregularities should be considered in women with newly diagnosed IBD. Patients can be reassured that cycles typically become more regular over time.

Background: Patients with undiagnosed inflammatory bowel disease (IBD) are often evaluated initially by primary care physicians (PCPs). Despite the frequency with which PCPs evaluate chronic abdominal pain and chronic diarrhea, little is known about how they approach these symptoms., Objectives: To determine the diagnostic practices and referral patterns of PCPs when confronting a patient with potential IBD., Methods: We conducted a mail survey of PCPs practicing in Rhode Island. Clinical vignettes describing patients with chronic abdominal pain and chronic diarrhea were presented. Respondents were asked to indicate how they would evaluate these scenarios and when they would refer to a specialist., Results: 432 PCPs were surveyed; 35.6% responded. Wide variation in PCPs' definitions of chronic abdominal pain and chronic diarrhea was found, with only 26% and 51% of physicians, respectively, defining these symptoms to be chronic per standard definitions. Laboratory testing was found to vary significantly with practice type (p < 0.01 for 2 patient groups). Patient age influenced the ordering of diagnostic imaging (p < 0.0001), while patient gender did not., Conclusions: There is significant variability among PCPs in the threshold after which common gastrointestinal symptoms become chronic as well as in their diagnostic evaluation of these symptoms. This variability may lead to a lag in the diagnosis of IBD and influence patient outcomes.

Osteoporosis secondary to glucocorticoid use is a potentially preventable disorder. It is the role of the physician to establish and maintain disease remission, minimize the use of glucocorticoids, and initiate measures to prevent and treat bone loss. The essentials of management include lifestyle modifications, nutritional interventions, and pharmacologic therapies. Bisphosphonates should be used when indicated.

Objectives: In this study we aimed to define the rate of early surgery for Crohn's disease and to identify risk factors associated with early surgery as a basis for subsequent studies of early intervention in Crohn's disease., Methods: We assembled a retrospective cohort of patients with Crohn's disease diagnosed between 1991 and 1997 and followed for at least 3 yr, who were identified in 16 community and referral-based practices in New England. Chart review was performed for each patient. Details of baseline demographic and disease features were recorded. Surgical history including date of surgery, indication, and procedure were also noted. Risk factors for early surgery (defined as major surgery for Crohn's disease within 3 yr of diagnosis, exclusive of major surgery at time of diagnosis) were identified by univariate analysis. Multiple logistic regression was used to identify independent risk factors., Results: Of 345 eligible patients, 69 (20.1%) required surgery within 3 yr of diagnosis, excluding the 14 patients (4.1%) who had major surgery at the time of diagnosis. Overall, the interval between diagnosis and surgery was short; one half of all patients who required surgery underwent operation within 6 months of diagnosis. Risk factors identified by univariate analysis as significantly associated with early surgery included the following: smoking; disease of small bowel without colonic involvement; nausea and vomiting or abdominal pain on presentation; neutrophil count; and steroid use in the first 6 months. Disease localized to the colon only, blood in the stool, use of 5-aminosalicylate, and lymphocyte count were inversely associated with risk of early surgery. Logistic regression confirmed independent associations with smoking as a positive risk factor and involvement of colon without small bowel as a negative risk factor for early surgery., Conclusions: The rate of surgery is high in the first 3 yr after diagnosis of Crohn's disease, particularly in the first 6 months. These results suggest that improved risk stratification and potent therapies with rapid onset of action are needed to modify the natural history of Crohn's disease.

Small conductance Ca2+-activated K+ (SK) channels have been cloned from mammalian brain, but little is known about the molecular characteristics of SK channels in nonexcitable tissues. Here, we report the isolation from rat liver of an isoform of SK3. The sequence of the rat liver isoform differs from rat brain SK3 in five amino acid residues in the NH3 terminus, where it more closely resembles human brain SK3. SK3 immunoreactivity was detectable in hepatocytes in rat liver and in HTC rat hepatoma cells. Human embryonic kidney (HEK-293) cells transfected with liver SK3 expressed 10 pS K+ channels that were Ca2+ dependent (EC(50) 630 nM) and were blocked by the SK channel inhibitor apamin (IC(50) 0.6 nM); whole cell SK3 currents inactivated at membrane potentials more positive than -40 mV. Notably, the Ca2+ dependence, apamin sensitivity, and voltage-dependent inactivation of SK3 are strikingly similar to the properties of hepatocellular and biliary epithelial SK channels evoked by metabolic stress. These observations raise the possibility that SK3 channels influence membrane K+ permeability in hepatobiliary cells during liver injury.

Despite abundant evidence for changes in mitochondrial membrane permeability in tumor necrosis factor (TNF)-mediated cell death, the role of plasma membrane ion channels in this process remains unclear. These studies examine the influence of TNF on ion channel opening and death in a model rat liver cell line (HTC). TNF (25 ng/ml) elicited a 2- and 5-fold increase in K(+) and Cl(-) currents, respectively, in HTC cells. These increases occurred within 5-10 min after TNF exposure and were inhibited either by K(+) or Cl(-) substitution or by K(+) channel blockers (Ba(2+), quinine, 0.1 mm each) or Cl(-) channel blockers (10 microm 5-nitro-2-(3-phenylpropylamino)benzoic acid and 0.1 mm N-phenylanthranilic acid), respectively. TNF-mediated increases in K(+) and Cl(-) currents were each inhibited by intracellular Ca(2+) chelation (5 mm EGTA), ATP depletion (4 units/ml apyrase), and the protein kinase C (PKC) inhibitors chelerythrine (10 micrometer) or PKC 19-36 peptide (1 micrometer). In contrast, currents were not attenuated by the calmodulin kinase II 281-309 peptide (10 micrometer), an inhibitor of calmodulin kinase II. In the presence of actinomycin D (1 micrometer), each of the above ion channel blockers significantly delayed the progression to TNF-mediated cell death. Collectively, these data suggest that activation of K(+) and Cl(-) channels is an early response to TNF signaling and that channel opening is Ca(2+)- and PKC-dependent. Our findings further suggest that K(+) and Cl(-) channels participate in pathways leading to TNF-mediated cell death and thus represent potential therapeutic targets to attenuate liver injury from TNF.

Subacute hepatitis and liver failure occurred in a 40-yr-old woman following a 1-month course of treatment with the nonsteroidal anti-inflammatory drug bromfenac. Serologies for hepatitis A, B, and C were negative, as were antinuclear antibodies and ceruloplasmin. A transjugular liver biopsy demonstrated submassive hepatic necrosis. The clinical course was complicated by encephalopathy, fluid retention, and spontaneous bacterial peritonitis, prompting consideration for liver transplantation. With supportive measures, jaundice and fluid retention resolved over a 3-month period. We conclude that prolonged use of bromfenac was the etiological agent in this case, and that this drug can cause severe hepatotoxicity resulting in liver failure.

Cells involved in the retrieval and metabolic conversion of amino acids undergo significant increases in size in response to amino acid uptake. The resultant adaptive responses to cell swelling are thought to include increases in membrane K+ and Cl- permeability through activation of volume-sensitive ion channels. This viewpoint is largely based on experimental models of hypotonic swelling, but few mammalian cells experience hypotonic challenge in vivo. Here we have examined volume regulatory responses in a physiological model of cell-swelling alanine uptake in immortalized hepatocytes. Alanine-induced cell swelling was followed by a decrease in cell volume that was temporally associated with an increase in membrane Cl- currents. These currents were dependent both on alanine concentration and Na+, suggesting that currents were stimulated by Na+-coupled alanine uptake. Cl- currents were outwardly rectifying, exhibited an anion permeability sequence of I- > Br- > Cl-, and were inhibited by the Cl- channel blocker 5-nitro-2-(3-phenylpropylamino)benzoic acid, features similar to those reported for a widely distributed class of volume-sensitive anion channels evoked by experimental hypotonic stress. These findings suggest that volume-sensitive anion channels participate in adaptive responses to amino acid uptake and provide such channels with a new physiological context.

In liver cells, cation-selective channels are permeable to Ca2+ and have been postulated to represent a pathway for receptor-mediated Ca2+ influx. This study examines the mechanisms involved in the regulation of these channels in a model liver cell line. Using patch-clamp recording techniques, it is shown that channel open probability is a saturable function of cytosolic [Ca2+], with half-maximal opening at 660 nm. By contrast, channel opening is not affected by membrane voltage or cytosolic pH. In intact cells, reduction of cytosolic [Cl-], a physiological response to Ca2+-mobilizing hormones and cell swelling, is also associated with an increase in channel opening. Finally, channel opening is inhibited by intracellular ATP through a mechanism that does not involve ATP hydrolysis. These findings suggest that opening of cation-selective channels is coupled to the metabolic state of the cell and provides a positive feedback mechanism for regulation of receptor-mediated Na+ and Ca2+ influx.

Fulminant hepatic failure is a devastating complication of viral hepatitis, hepatotoxic exposures, and a variety of other acute liver diseases. Although this syndrome is associated with high mortality, liver transplantation can be life saving. This article discusses the medical management of fulminant hepatic failure and emphasizes complications, determinants of survival, and patient selection for liver transplantation.

A variety of hormonal agonists activate transmembrane Na+ and Ca2+ flux in hepatocytes, but the responsible mechanisms are poorly understood. We employed microfluorimetric and patch clamp recording techniques in hepatocytes to determine the effect of the hormone vasopressin on cytosolic Na+ concentration ([Na+]i) and to identify the transmembrane Na+ transport pathways activated by this agonist. Under basal conditions, [Na+]i, measured using the Na(+)-sensitive fluorophore sodium-binding benzofuran isophthalate, averaged 12.1 +/- 1.6 mM. Exposure to vasopressin rapidly increased [Na+]i by 8.3 +/- 0.9 mM. This increase was attributable to activation of Na+ influx. It occurred in the absence of solutes co-transported with Na+ and was not associated with activation of Na+/H+ antiport. In cell-attached membrane patches, vasopressin activated ion channels that carried inward positive current at the resting membrane potential. Further characterization in excised membrane patches revealed two classes of ion channels, with conductances of 16.0 +/- 2.8 and 30.9 +/- 3.1 picosiemens, respectively. Single channel currents reversed near 0 mV, and ion substitution studies demonstrated that each channel type was permeable to Na+, Ca2+, and K+ but not Cl-. These observations in hepatocytes indicate that vasopressin increases [Na+]i and activates cation-selective channels, which likely accounts for vasopressin-activated Na+ and Ca2+ influx.

In conclusion, the availability of liver transplantation has dramatically advanced the management of fulminant hepatic failure. A major responsibility of the gastroenterologist/hepatologist involved in the care of patients with liver failure is early decision making regarding likelihood of spontaneous recovery and consideration toward referral to a transplantation center. In particular, patients with exposure to drugs or toxins (other than acetaminophen); patients with presumed non-A, non-B hepatitis; children or older patients; patients with prolonged jaundice; profoundly jaundiced patients; or patients with severe coagulopathy should be given the highest consideration for urgent transplantation. Supportive care should take into account the potential complications of bleeding, sepsis, cerebral edema, renal failure, and respiratory failure. Such complications are the major limiting factors that prevent patients with fulminant hepatic failure from undergoing liver transplantation and contribute to the majority of postoperative deaths among patients who undergo transplantation. If these issues are heeded, and in light of emerging therapeutic modalities and surgical innovations, it is anticipated that ongoing improvement of the overall outcome of patients with fulminant hepatic failure will continue to be seen.

Intracellular pH influences and is influenced by a diverse array of hepatocellular processes. It is regulated by the concerted action of three plasma membrane H+/HCO3- transporters that serve to buffer against both acidic (Na+/H+ exchange, Na+/HCO3- cotransport) and basic (Cl-/HCO3- exchange) metabolic challenges. The responsiveness of hepatocytes to these challenges is augmented by a regulatory interplay between pH-mediated changes in Vm and electrogenic Na+/HCO3- cotransport to maintain pHi and Vm within a range optimized to serve liver function. The cost is expenditure of metabolic energy to sustain increased activity of the Na+/K+ pump. The benefit is a dynamic servomechanism well-suited to the metabolic demands of hepatocytes, which may be found in future studies to be employed in other metabolically active epithelia as well.

Cerebral edema and intracranial hypertension, commonly present in fulminant hepatic failure, may lead to brainstem herniation and limit the survival of comatose patients awaiting liver transplantation before a donor organ becomes available. Also, they are likely responsible for postoperative neurological morbidity and mortality. Although intracranial pressure monitoring has been proposed to aid clinical decision making in this setting, its use in the prevention of brainstem herniation preoperatively, in the selection of patients for liver transplantation who have the potential for neurological recovery and in the maintenance of cerebral perfusion during liver transplantation has not been examined in detail. To address these issues, we established a protocol for intracranial pressure monitoring in comatose patients with fulminant hepatic failure as part of their preoperative and intraoperative management. Twenty adults and three children underwent intracranial pressure monitoring. Ten patients required preoperative medical therapy with mannitol, barbiturates or both for a rise in intracranial pressure above 25 mm Hg. Four patients had a sustained lowering of intracranial pressure, three of whom survived hospitalization. Six patients had intracranial hypertension refractory to medical management, were removed from a waiting list for a donor organ and died with brainstem herniation. Of the remaining 17 patients, 3 died of other causes while awaiting a donor organ, 2 recovered spontaneously without neurological sequelae and 12 underwent liver transplantation. All but one patient undergoing liver transplantation had transient intraoperative intracranial hypertension develop, requiring medical treatment. The 12 patients who had transplants recovered neurologically and were discharged from the hospital.(ABSTRACT TRUNCATED AT 250 WORDS)