Cytokinin signaling promotes root hair growth by directly regulating RSL4 expression.

Root hairs are single-celled tubular structures produced from the epidermis, which play an essential role in water and nutrient uptake from the soil. Therefore, root hair formation and elongation are controlled not only by developmental programs but also by environmental factors, enabling plants to survive under fluctuating conditions. Phytohormones are key signals that link environmental cues to developmental programs; indeed, root hair elongation is known to be controlled by auxin and ethylene. Another phytohormone, cytokinin, also affects root hair growth, while whether cytokinin is actively involved in root hair growth and, if so, how it regulates the signaling pathway governing root hair development have remained unknown. In this study, we show that the two-component system of cytokinin, which involves the B-type response regulators ARABIDOPSIS RESPONSE REGULATOR 1 (ARR1) and ARR12, promotes the elongation process of root hairs. They directly up-regulate ROOT HAIR DEFECTIVE 6-LIKE 4 (RSL4) encoding a basic helix-loop-helix (bHLH) transcription factor that plays a central role in root hair growth, whereas the ARR1/12-RSL4 pathway does not crosstalk with auxin or ethylene signaling. These results indicate that cytokinin signaling constitutes another input onto the regulatory module governed by RSL4, making it possible to fine-tune root hair growth in changing environments.

Functional MRI and delay discounting in patients infected with hepatitis C.

Hepatitis C virus-infected (HCV+) adults evidence increased rates of psychiatric and cognitive difficulties. This is the first study to use functional magnetic resonance imaging (fMRI) to examine brain activation in untreated HCV+ adults. To determine whether, relative to non-infected controls (CTLs), HCV+ adults exhibit differences in brain activation during a delay discounting task (DDT), a measure of one's tendency to choose smaller immediate rewards over larger delayed rewards-one aspect of impulsivity. Twenty adults with HCV and 26 CTLs completed an fMRI protocol during the DDT. Mixed effects regression analyses of hard versus easy trials of the DDT showed that, compared with CTLs, the HCV+ group exhibited less activation in the left lateral occipital gyrus, precuneus, and superior frontal gyrus. There were also significant interactive effects for hard-easy contrasts in the bilateral medial frontal gyrus, left insula, left precuneus, left inferior parietal lobule, and right temporal occipital gyrus; the CTL group evidenced a positive relationship between impulsivity and activation, while the HCV+ group exhibited a negative relationship. Within the HCV+ group, those with high viral load chose immediate rewards more often than those with low viral load, regardless of choice difficulty; those with low viral load chose immediate rewards more often on hard choices relative to easy choices. Results show that HCV+ patients exhibit greater impulsive behavior when presented with difficult choices, and impulsivity is negatively related to activation in regions important for cognitive control. Thus, interventions that decrease impulsive choice may be warranted with some HCV+ patients.

Pain and self-care behaviours in adult patients with end-stage liver disease: a longitudinal description.

This prospective descriptive study investigated pain characteristics in 20 outpatients with endstage liver disease (ESLD) who were approaching the end of life, described variability in pain between and within patients, and described the pharmacological and nonpharmacological pain management strategies used. The instruments we utilized were the Brief Pain Inventory (BPI) and the self-care behaviour (SCB) log for pain. Data were collected once a month over a six-month period. BPI severity of, and interference from pain mean scores ranged from 5.52 to 6.03 and 5.36 to 6.64, respectively. The top three pain-relieving behaviours reported by patients were "taking pain medication," "taking a nap," and "asking for help." Pain medication intake-differed between patients who were pursuing a liver transplant and those who were not eligible for one. If we are to effectively improve care for ESLD patients, it is essential that we understand the ways in which these patients experience pain and the pain management strategies they employ.

Protective effects of higher cognitive reserve for neuropsychological and daily functioning among individuals infected with hepatitis C.

Higher levels of cognitive reserve (CR) can be protective against the neuropsychological manifestation of neural injury across a variety of clinical disorders. However, the role of CR in the expression of neurocognitive deficits among persons infected with the hepatitis C virus (HCV) is not well understood. Thirty-nine HCV-infected participants were classified as having either high (n = 19) or low (n = 20) CR based on educational attainment, oral word reading, and IQ scores. A sample of 40 demographically comparable healthy adults (HA) was also included. All participants completed the Neuropsychological Assessment Battery, Delis-Kaplan Executive Function System, and Behavioral Rating Inventory of Executive Function, Adult Version (BRIEF-A). Linear regression analyses, controlling for gender, depression, and lifetime substance use disorders, found significant effects of HCV/CR group on verbal fluency, executive functions, and daily functioning T scores, but not in learning or the BRIEF-A. Pairwise comparisons revealed that the HCV group with low CR performed significantly below the HCV high CR and HA cohorts, who did not differ from one another. Findings indicate that higher levels of CR may be a protective factor in the neurocognitive and real-world manifestation of neural injury commonly associated with HCV infection.

Hepatic and cardiac iron overload among patients with end-stage liver disease referred for liver transplantation.

BACKGROUND: Iron overload is associated with fatal cardiovascular events following liver transplantation. Myocardial iron deposits were observed post-mortem in patients who died of cardiac events after transplantation at our institution. This observation prompted testing to exclude cardiac iron in subsequent transplant candidates. AIMS: To assess the results of testing for iron overload in liver transplant candidates at our institution. METHODS: Ferritin, TIBC, and serum iron were measured in cirrhotics referred for transplantation. Patients with transferrin saturation ≥50% and ferritin ≥250 ng/mL underwent liver biopsy graded for iron. Patients with 3-4+ hepatic iron deposits underwent HFE mutation analysis and endomyocardial biopsy with iron staining. RESULTS: Eight hundred and fifty-six patients were evaluated for liver transplantation between January 1997 and March 2005. Two hundred and eighty-seven patients (34%) had transferrin saturation ≥50% and ferritin ≥250 ng/mL. Patients with markers of iron overload had more advanced liver disease than those with normal iron indices. One hundred and fifty-three patients underwent liver biopsy. Twenty-six patients (17%) had 3-4+ hepatic iron staining. One patient was a C282Y heterozygote. Endomyocardial biopsy was performed in 14 patients of whom nine had cardiac iron deposition. CONCLUSIONS: Non-HFE-related cardiac iron overload can occur in advanced liver disease We therefore recommend screening for cardiac iron prior to liver transplantation.

The cognitive effects of hepatitis C in the presence and absence of a history of substance use disorder.

The aim of the study was to determine whether infection with the hepatitis C virus (HCV) is associated with cognitive impairment beyond the effects of prevalent comorbidities and a history of substance use disorder (SUD). Adult veterans were recruited from the Portland Veterans Affairs Medical Center into three groups: (1) HCV+/SUD+ (n = 39), (2) HCV+/SUD- (n = 24), and (3) HCV-/SUD- (n = 56). SUD+ participants were in remission for > or =90 days, while SUD- participants had no history of SUD. Groups did not significantly differ in terms of rates of psychiatric or medical comorbidities. Procedures included clinical interviews, medical record reviews, and neuropsychological testing. Significant group differences were found in the domains of Verbal Memory, Auditory Attention, Speeded Visual Information Processing, and Reasoning/Mental Flexibility (p

Living With Hepatocellular Carcinoma Near the End of Life: Family Caregivers' Perspectives.

PURPOSE/OBJECTIVES: To explore family caregivers' perspectives of caring for patients with terminal hepatocellular carcinoma (HCC) as patients approached the end of life.
. RESEARCH APPROACH: Longitudinal, qualitative descriptive design.
. SETTING: Oregon Health and Science University in Portland and Veterans Affairs Portland Health Care System in Oregon.
. PARTICIPANTS: 13 family caregivers with a mean age of 56 years (range = 22-68 years). The majority of family caregivers were female (n = 10) and identified as White (n = 11).
. METHODOLOGIC APPROACH: Interview data were collected from family caregivers once a month for as many as six months, for a total of 39 interviews. Data were analyzed using conventional content analysis.
. FINDINGS: Five core categories and nine subcategories were identified. From the time of the terminal diagnosis to the end of life, family caregivers felt unprepared, uncertain, and in need of information. They struggled with whether symptoms were HCC- or cirrhosis-related.
. INTERPRETATION: Nurses can support family caregivers by eliciting their knowledge and concerns, and attending to symptom presentation and interpretation and to treatment challenges. Understanding challenges caregivers experience is crucial for developing interventions that address their desire for information, support, and help along the HCC disease trajectory.
. IMPLICATIONS FOR NURSING: Nurses play a critical role in preparing caregivers to understand the importance of pain assessment and management and early referral to palliative care.

A longitudinal study evaluating the effects of interferon-alpha therapy on cognitive and psychiatric function in adults with chronic hepatitis C.

OBJECTIVE: To prospectively evaluate for changes in objective cognitive performance (attention, memory, and executive function) and psychiatric symptom severity (depression, anxiety, fatigue, and pain) in patients before, during and after interferon-alpha based therapy (IFN) for chronic hepatitis C virus infection (HCV). METHODS: 33 HCV+ adults were evaluated two months before IFN initiation (baseline), three months into IFN, and six months following IFN termination (IFN+ Group). 31 HCV+ adults who did not undergo IFN therapy were evaluated at baseline and six months later (IFN- Group). At each evaluation, participants completed the Neuropsychological Assessment Battery (NAB) Attention, Memory and Executive Functions Modules, the Beck Depression Inventory, Second Edition (BDI), Generalized Anxiety Disorder Inventory (GADI), Fatigue Severity Scale (FSS), and Brief Pain Inventory (BPI). RESULTS: Compared with the IFN- Group, the IFN+ Group experienced significantly (p<0.050) increased symptoms of depression, anxiety, fatigue and pain during IFN therapy relative to baseline. In the IFN+ Group, psychiatric symptoms generally returned to baseline levels following IFN termination. Sustained viral response was associated with significantly lower depression and fatigue. No significant changes in cognitive performance were observed. CONCLUSIONS: During IFN, patients with HCV evidence significantly increased psychiatric symptoms, including symptoms of depression, anxiety, fatigue and pain. These psychiatric symptoms are generally short-term and remit following IFN termination, with increased benefit if viral clearance is achieved. However, IFN is not associated with significant declines in objective cognitive performance during or following IFN.

Multi-analyte profile analysis of plasma immune proteins: altered expression of peripheral immune factors is associated with neuropsychiatric symptom severity in adults with and without chronic hepatitis C virus infection.

BackgroundThe purpose of this study was to characterize hepatitis C virus (HCV)-associated differences in the expression of 47 inflammatory factors and to evaluate the potential role of peripheral immune activation in HCV-associated neuropsychiatric symptoms-depression, anxiety, fatigue, and pain. An additional objective was to evaluate the role of immune factor dysregulation in the expression of specific neuropsychiatric symptoms to identify biomarkers that may be relevant to the treatment of these neuropsychiatric symptoms in adults with or without HCV. MethodsBlood samples and neuropsychiatric symptom severity scales were collected from HCV-infected adults (HCV+, n = 39) and demographically similar noninfected controls (HCV-, n = 40). Multi-analyte profile analysis was used to evaluate plasma biomarkers. ResultsCompared with HCV- controls, HCV+ adults reported significantly (P < 0.050) greater depression, anxiety, fatigue, and pain, and they were more likely to present with an increased inflammatory profile as indicated by significantly higher plasma levels of 40% (19/47) of the factors assessed (21%, after correcting for multiple comparisons). Within the HCV+ group, but not within the HCV- group, an increased inflammatory profile (indicated by the number of immune factors > the LDC) significantly correlated with depression, anxiety, and pain. Within the total sample, neuropsychiatric symptom severity was significantly predicted by protein signatures consisting of 4-10 plasma immune factors; protein signatures significantly accounted for 19-40% of the variance in depression, anxiety, fatigue, and pain. ConclusionsOverall, the results demonstrate that altered expression of a network of plasma immune factors contributes to neuropsychiatric symptom severity. These findings offer new biomarkers to potentially facilitate pharmacotherapeutic development and to increase our understanding of the molecular pathways associated with neuropsychiatric symptoms in adults with or without HCV.

End-stage liver disease: challenges and practice implications.

As the seventh leading cause of death among people aged 25 to 64 years, end-stage liver disease (ESLD) affects many Americans in the most productive years of their lives. Despite the increasing number of individuals who are dying of ESLD, little is documented about their end of life challenges as the disease progresses. The purpose of this article is to highlight specific challenges for people with ESLD, their families, and their implications for health care providers: ascites, spontaneous bacterial peritonitis, hepatic encephalopathy, malnutrition, altered drug metabolism, renal insufficiency and hyponatremia, hepatocellular carcinoma, and pain. The authors also present a case study to illustrate disease progression and difficulties facing patients, family members, and providers.

Differential antigenic hierarchy associated with spontaneous recovery from hepatitis C virus infection: implications for vaccine design.

BACKGROUND: Cellular immune responses play a central role in the control of hepatitis C virus (HCV) infection, and in some individuals the adaptive immune response can spontaneously eradicate HCV infection. The development of vaccine candidates to prevent the spread of this infection remains a top priority; however, understanding the correlates of effective immunological containment is an important prerequisite. METHODS: Using 750 overlapping peptides, we directly characterized ex vivo total and subgenomic HCV-specific CD4(+) and CD8(+) T cell responses in a large cohort of participants with either chronic infection or spontaneously resolved infection. RESULTS: In chronic infection, the frequency of total CD4(+) T cells specific for HCV averaged 0.06%, compared with 0.38% in resolved infection. Total HCV-specific CD4(+) and CD8(+) T cell responses were strongly correlated in the setting of spontaneous resolution but not in the setting of viral persistence. NS3 protein-specific responses comprised a significantly greater proportion of the total response in resolved infection than in chronic infection, whereas responses to different regions comprised a larger proportion of responses in chronic infection. CONCLUSION: Because these data comprehensively define the breadth, specificity, and threshold of the T cell response associated with spontaneous recovery from HCV infection, they have important implications in the development of multigenic vaccine candidates for this common infection.

Prospective multicenter study of eligibility for antiviral therapy among 4,084 U.S. veterans with chronic hepatitis C virus infection.

BACKGROUND: Many veterans may not be candidates for hepatitis C virus (HCV) treatment due to contraindications to therapy. The aims of this study were to determine the proportion of HCV-infected veterans who were eligible for interferon alfa and ribavirin therapy and to evaluate barriers to HCV treatment. METHODS: We prospectively enrolled 4,084 veterans who were referred for HCV treatment over a 1-yr period at 24 Veterans Affairs (VA) Medical Centers. Treatment candidacy was assessed using standardized criteria and the opinion of the treating clinician. RESULTS: Overall, 32.2% (95% CI, 30.8-33.7%) were candidates for HCV treatment according to standardized criteria, whereas 40.7% (95% CI, 39.2-42.3%) were candidates in the opinion of the treating clinician. Multivariable analysis identified ongoing substance abuse (OR = 17.68; 95% CI, 12.24-25.53), comorbid medical disease (OR = 9.62; 95% CI, 6.85-13.50), psychiatric disease (OR = 9.45; 95% CI, 6.70-13.32), and advanced liver disease (OR = 8.43; 95% CI, 4.42-16.06) as the strongest predictors of not being a treatment candidate. Among patients who were considered treatment candidates, 76.2% (95% CI, 74.0-78.3%) agreed to be treated and multivariable analysis showed that persons >/=50 yr of age (OR = 1.37; 95% CI, 1.07-1.76) and those with >50 lifetime sexual partners (OR = 1.44; 95% CI, 1.08-1.93) were more likely to decline treatment. CONCLUSIONS: The majority of veteran patients are not suitable candidates for HCV treatment because of substance abuse, psychiatric disease, and comorbid medical disease, and many who are candidates decline therapy. Multidisciplinary collaboration is needed to overcome barriers to HCV therapy in this population.

Elevated prevalence of hepatitis C infection in users of United States veterans medical centers.

Several studies suggest veterans have a higher prevalence of hepatitis C virus infection than nonveterans, possibly because of military exposures. The purpose of this study was to estimate the prevalence of anti-hepatitis C antibody and evaluate factors associated with infection among users of Department of Veterans Affairs medical centers. Using a two-staged cluster sample, 1288 of 3863 randomly selected veterans completed a survey and underwent home-based phlebotomy for serological testing. Administrative and clinical data were used to correct the prevalence estimate for nonparticipation. The prevalence of antihepatitis C antibody among serology participants was 4.0% (95% CI, 2.6%-5.5%). The estimated prevalence in the population of Veterans Affairs medical center users was 5.4% (95% CI, 3.3%-7.5%) after correction for sociodemographic and clinical differences between participants and nonparticipants. Significant predictors of seropositivity included demographic factors, period of military service (e.g., Vietnam era), prior diagnoses, health care use, and lifestyle factors. At least one traditional risk factor (transfusion or intravenous drug use) was reported by 30.2% of all subjects. Among those testing positive for hepatitis C antibody, 78% either had a transfusion or had used injection drugs. Adjusting for injection drug use and nonparticipation, seropositivity was associated with tattoos and incarceration. Military-related exposures were not found to be associated with infection in the adjusted analysis. In conclusion, the prevalence of hepatitis C in these subjects exceeds the estimate from the general US population by more than 2-fold, likely reflecting more exposure to traditional risk factors among these veterans.

Novel CD4+ and CD8+ T-cell determinants within the NS3 protein in subjects with spontaneously resolved HCV infection.

Spontaneous resolution of hepatitis C virus (HCV) infection is a relatively infrequent event, and these individuals provide a unique opportunity to characterize correlates of protective immunity as an important first step in the development of vaccine candidates. The aim of this study was to directly and comprehensively enumerate HCV-nonstructural protein 3 (NS3) specific CD4(+) and CD8(+) T cells ex vivo from HLA diverse individuals who had been successful in spontaneously resolving HCV infection. We measured interferon gamma (IFN-gamma) production with an ELISPOT assay using magnetic bead-separated CD4(+) or CD8(+) T cells in response to autologous DCs that had been pulsed with 15mer per peptides overlapping by 11 amino acids and spanning all of the NS3 protein (150 total peptides). All subjects with spontaneously recovered HCV infection demonstrated vigorous and multispecific CD4(+) T-cell responses to NS3 peptides, and 6 of 10 subjects demonstrated CD8(+) T-cell responses. More importantly, we identified novel, previously unpredicted antigenic regions, which in most cases elicited high frequencies within a given individual. In conclusion, subjects who have spontaneously eradicated HCV infection up to 35 years earlier demonstrate persistent CD4(+) and CD8(+) T-cell responses specific to NS3. By providing a comprehensive screening of all potential T-cell epitopes contained in the NS3 region, our strategy defines the breadth of the T-cell response and identifies novel, unpredicted specificities.

Comparative analysis of outcome following liver transplantation in US veterans.

The purpose of this study was to evaluate whether there was a difference in mortality following orthotopic liver transplantation (OLT) in a US veteran (VA) population (n = 149) compared to a non-VA (university) population (n = 285) and what factors could explain this difference. Survival following OLT for 149 VA patients was compared with that of 285 university patients. By Kaplan-Meier survival analysis, VA patients had higher mortality than university patients with respective 1-year, 3-year, and 5-year survival of 82%, 75%, and 68% vs. 87%, 82%, and 78% (p = 0.006). Gender, etiology of end-stage liver disease (ESLD) and donor age (i.e. older than 34 years) also significantly influenced survival. However, when donor and recipient age, gender, model for end-stage liver disease (MELD) score, and etiology of liver disease were included with hospital status in a multivariate Cox proportional hazards model, the VA population did not have higher mortality. A final model to predict mortality following transplantation was derived for all 434 patients where individuals were assigned risk scores based on the equation R = 0.219 (gender) + 0.018 (donor age) + 0.032 (recipient age) + 0.021 (MELD), where recipient age, donor age, and MELD score are the respective continuous variables and gender = 1 (men) and 0 for women (c-statistic = 0.71).

Frequencies of HCV-specific effector CD4+ T cells by flow cytometry: correlation with clinical disease stages.

Hepatitis C virus (HCV) is the leading cause of chronic hepatitis, affecting approximately 2% of the world's population. The immune mechanisms responsible for the highly variable natural history in a given individual are unknown. We used a multiparameter flow cytometric technique to functionally and phenotypically characterize HCV-specific effector T cells in the peripheral blood of 32 individuals with different stages of hepatitis C disease (resolved, mild chronic, advanced chronic) and normal controls. We found the highest frequencies of virus-specific effector cells with an activated memory phenotype (CD45RO+CD69+) in subjects who had resolved HCV infection, either spontaneously or with antiviral therapy. Effector cells from patients with resolved infection produced Th1 type cytokines following stimulation with nonstructural antigens (NS3 and NS4), whereas effector cells from chronically infected patients produced Th1 type cytokines predominantly following stimulation with the HCV core antigen. Stimulation with superantigen staphylococcal enterotoxin (SEB) induced the same levels of cytokine production in the different patient groups. Among the HCV-seropositive patients, viral load inversely correlated with the Th1 effector cell response to NS3. Interleukin (IL)-4 was produced only in response to the control antigens, but not in response to the HCV recombinant proteins. Taken together, these findings suggest that a vigorous HCV-specific CD4+ Th1 response, particularly against the nonstructural proteins of the virus, may be associated with viral clearance and protection from disease progression. Prospective studies using this new flow cytometric assay will be required to determine whether antiviral therapy modifies the frequency, specificity, and function of these virus-specific effector cells.