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1.
J Biol Chem ; 298(12): 102597, 2022 12.
Article in English | MEDLINE | ID: mdl-36244454

ABSTRACT

Most eukaryotic secretory proteins are cotranslationally translocated through Sec61 into the endoplasmic reticulum (ER). Because these proteins have evolved to fold in the ER, their mistargeting is associated with toxicity. Genetic experiments have implicated the ER heat shock protein 70 (Hsp70) Hspa13/STCH as involved in processing of nascent secretory proteins. Herein, we evaluate the role of Hspa13 in protein import and the maintenance of cellular proteostasis in human cells, primarily using the human embryonic kidney 293T cell line. We find that Hspa13 interacts primarily with the Sec61 translocon and its associated factors. Hspa13 overexpression inhibits translocation of the secreted protein transthyretin, leading to accumulation and aggregation of immature transthyretin in the cytosol. ATPase-inactive mutants of Hspa13 further inhibit translocation and maturation of secretory proteins. While Hspa13 overexpression inhibits cell growth and ER quality control, we demonstrate that HSPA13 knockout destabilizes proteostasis and increases sensitivity to ER disruption. Thus, we propose that Hspa13 regulates import through the translocon to maintain both ER and cytosolic protein homeostasis. The raw mass spectrometry data associated with this article have been deposited in the PRIDE archive and can be accessed at PXD033498.


Subject(s)
Heat-Shock Proteins , Proteostasis , Humans , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Prealbumin/metabolism , Cytosol/metabolism , Endoplasmic Reticulum/genetics , Endoplasmic Reticulum/metabolism , Protein Transport , SEC Translocation Channels/metabolism
2.
Cancer ; 128(1): 192-202, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34460935

ABSTRACT

BACKGROUND: Little is known about cancer survivors who discontinue survivorship care. The objective of this study was to characterize patients with head and neck cancer who discontinue survivorship care with their treating institution and identify factors associated with discontinuation. METHODS: This was a retrospective cohort study of patients diagnosed with head and neck cancer between January 1, 2014, and December 31, 2016, who received cancer-directed therapy at the University of Iowa Hospitals and Clinics (UIHC). Eligible patients achieved a cancer-free status after curative-intent treatment and made at least 1 visit 90+ days after treatment completion. The primary outcome was discontinuation of survivorship care, which was defined as a still living survivor who had not returned to a UIHC cancer clinic for twice the expected interval. Demographic and oncologic factors were examined to identify associations with discontinuation. RESULTS: Ninety-seven of the 426 eligible patients (22.8%) discontinued survivorship care at UIHC during the study period. The mean time in follow-up for those who discontinued treatment was 15.4 months. Factors associated with discontinuation of care included an unmarried status (P = .036), a longer driving distance to the facility (P = .0031), and a single-modality cancer treatment (P < .0001). Rurality was not associated with discontinuation (24.3% vs 21.6% for urban residence; P = .52), nor was age, gender, or payor status. CONCLUSIONS: The study results indicate that a sizeable percentage of head and neck cancer survivors discontinue care with their treating institution. Both demographic and oncologic factors were associated with discontinuation at the treating institution, and this points to potential clinical and care delivery interventions.


Subject(s)
Cancer Survivors , Head and Neck Neoplasms , Head and Neck Neoplasms/therapy , Humans , Retrospective Studies , Survivors , Survivorship
3.
Clin Gastroenterol Hepatol ; 17(5): 957-967.e7, 2019 04.
Article in English | MEDLINE | ID: mdl-30326298

ABSTRACT

BACKGROUND & AIMS: The American Association for the Study of Liver Diseases (AASLD) guidelines for treatment of chronic hepatitis B virus (HBV) infection have changed with time. We assessed rates of treatment evaluation and initiation in patients with chronic HBV infection from different practice settings in the past 14 years. METHODS: Treatment-naive patients with chronic HBV infection were recruited from different practice settings in California from January 2002 through December 2016. The study population comprised 4130 consecutive, treatment-naive patients with chronic HBV infection seen by community primary care physicians (n = 616), community gastroenterologists (n = 2251), or university hepatologists (n = 1263). Treatment eligibility was assessed using data from the first 6 months after initial presentation based on AASLD criteria adjusted for changes over time. RESULTS: Within the first 6 months of care, the proportions of patients evaluated by all 3 relevant tests (measurements of alanine aminotransferase, hepatitis B virus e antigen, and HBV DNA levels) were as follows: 36.69% in community primary care, 59.80% in gastroenterologist care, and 79.97% in hepatology care (P < .0001 among the 3 groups). Higher proportions of patients were eligible for treatment in specialty practices: 12.76% in community primary care, 24.96% in gastroenterologist care, and 29.43% in hepatology care (P < .0001). Among treatment-eligible patients, there was no significant difference in the proportions of patients who began antiviral therapy between those receiving treatment from a gastroenterologist (55.65%) vs a hepatologist (57.90%; P = .56). Of 243 evaluable patients receiving community primary care, only 31 were eligible for treatment and only 12 of these (38.71%) received treatment. CONCLUSIONS: In an analysis of patients receiving care for chronic HBV infection, we found the proportions evaluated and receiving treatment to be suboptimal, according to AASLD criteria, in all practice settings. However, rates of evaluation and treatment were lowest for patients receiving community primary care.


Subject(s)
Disease Management , Guideline Adherence/statistics & numerical data , Health Services Research , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/drug therapy , Primary Health Care/methods , Secondary Care/methods , Adolescent , Adult , Aged , Aged, 80 and over , California , Female , Humans , Male , Middle Aged , Young Adult
4.
Anal Bioanal Chem ; 411(19): 4987-4998, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31254054

ABSTRACT

Influenza infection requires viral escape from early endosomes into the cytosol, which is enabled by an acid-induced irreversible conformational transformation in the viral protein hemagglutinin. Despite the direct relationship between this conformational change and infectivity, label-free methods for characterizing this and other protein conformational changes in biological mixtures are limited. While the chemical reactivity of the protein backbone and side-chain residues is a proxy for protein conformation, coupling this reactivity to quantitative mass spectrometry is a challenge in complex environments. Herein, we evaluate whether electrophilic amidination coupled with pseudo-parallel reaction monitoring is an effective label-free approach to detect the fusion-associated conformational transformation in recombinant hemagglutinin (rHA). We identified rHA peptides that are differentially amidinated between the pre- and post-fusion states, and validated that this difference relies upon the fusion-associated conformational switch. We further demonstrate that we can distinguish the fusion profile in a matrix of digested cellular lysate. This fusion assay can be used to evaluate fusion competence for modified HA. Graphical abstract.


Subject(s)
Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Orthomyxoviridae/metabolism , Recombinant Fusion Proteins/chemistry , Viral Proteins/metabolism , Amides/metabolism , HEK293 Cells , Humans , Limit of Detection , Peptides/metabolism , Protein Binding , Protein Conformation , Reproducibility of Results , Tandem Mass Spectrometry , Viral Proteins/chemistry , Viral Proteins/classification
5.
J Gastroenterol Hepatol ; 30(1): 43-50, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25168842

ABSTRACT

BACKGROUND AND AIM: Suboptimal viral suppression with adefovir (ADV) poses a challenge in managing chronic hepatitis B. Few studies have evaluated the efficacy of entecavir (ETV) in ADV-experienced patients. Our aim is to assess treatment effectiveness of ETV in ADV-experienced patients. METHODS: ADV-experienced patients switched to ETV were enrolled from six US clinics. Patients completed a median of 24 months of ETV after switch. Patients were categorized into partial responders (detectable HBV-DNA at switch) or complete responders (undetectable HBV-DNA at switch) to ADV. Primary and secondary outcome measurements were complete viral suppression (CVS, HBV-DNA < 60 IU/mL) and biochemical response (BR, alanine aminotransferase [ALT] < 40 U/L), respectively. RESULTS: A total of 120 patients were included in the analysis (80 ADV partial responders; 40 ADV complete responders). In partial responders, CVS rate was 84% after 24 months of ETV. BR rate was 58% at switch to ETV and increased to 90% after 24 months. All complete responders continued to experience CVS after switch. On multivariate analysis inclusive of age, male gender, ALT level at switch, and history of lamivudine (LAM) exposure, we identified positive, hepatitis B e antigen status before ADV and higher HBV-DNA level at time of switch as significant independent negative predictors of CVS. In eight patients with ADV resistance, seven achieved CVS after 24 months of ETV, and all achieved BR. CONCLUSION: In ADV-experienced patients, high rates of CVS and BR can be achieved/sustained after switching to ETV, including those with ADV resistance or with prior exposure to LAM.


Subject(s)
Adenine/analogs & derivatives , Antiviral Agents/therapeutic use , Hepatitis B, Chronic/drug therapy , Organophosphonates/therapeutic use , Adenine/therapeutic use , Adult , Alanine Transaminase/blood , Biomarkers/blood , Drug Substitution , Female , Follow-Up Studies , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/virology , Humans , Lamivudine/therapeutic use , Male , Middle Aged , Multivariate Analysis , Time Factors , Treatment Outcome , Viral Load
6.
Dig Dis Sci ; 59(1): 168-73, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24248420

ABSTRACT

BACKGROUND AND AIMS: The dose recommendation for entecavir (ETV) is 0.5 mg daily for treatment-naïve chronic hepatitis B (CHB) patients and 1.0 mg daily for lamivudine-refractory patients; however, few data are available for the efficacy of a 1.0-mg daily dose in treatment-naïve CHB patients. Our goal is to examine the treatment outcome of treatment-naïve patients placed on ETV 0.5 mg or ETV 1.0 mg daily through week 48. METHODS: Cases were 40 consecutive hepatitis B e antigen (HBeAg)-positive CHB patients treated with ETV 1.0 mg daily between January 2005 and September 2010, and controls were 40 consecutive CHB patients treated with ETV 0.5 mg daily between January 2005 and September 2010 at three US gastroenterology/liver clinics. Controls were matched for age (±5 years), sex, HBeAg, and baseline hepatitis B virus (HBV) DNA (±0.5 log10 IU/ml). Complete viral suppression was defined as undetectable HBV DNA by polymerase chain reaction (<100 IU/ml). RESULTS: Both groups had similar distributions of age (38 ± 11 years), male patients (55 %), and mean HBV DNA (7.7 ± 1.1 log10 IU/ml). The complete viral suppression rate was similar in both cases and controls through week 24 (15 vs. 15 %, p = 1.00) and week 48 (22 vs. 36 %, p = 0.17). Non-adherence was reported in three patients in the ETV 1.0 mg daily cohort at week 48. CONCLUSIONS: There were no significant differences in the proportion of patients with complete viral suppression in patients treated with ETV 0.5 mg daily or the higher daily dose of 1.0 mg.


Subject(s)
Antiviral Agents/administration & dosage , Guanine/analogs & derivatives , Hepatitis B, Chronic/drug therapy , Adult , Female , Guanine/administration & dosage , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
7.
bioRxiv ; 2024 Aug 04.
Article in English | MEDLINE | ID: mdl-39131289

ABSTRACT

Genetic variants in TRIO are associated with neurodevelopmental disorders (NDDs) including schizophrenia (SCZ), autism spectrum disorder (ASD) and intellectual disability. TRIO uses its two guanine nucleotide exchange factor (GEF) domains to activate GTPases (GEF1: Rac1 and RhoG; GEF2: RhoA) that control neuronal development and connectivity. It remains unclear how discrete TRIO variants differentially impact these neurodevelopmental events. Here, we investigate how heterozygosity for NDD-associated Trio variants - +/K1431M (ASD), +/K1918X (SCZ), and +/M2145T (bipolar disorder, BPD) - impact mouse behavior, brain development, and synapse structure and function. Heterozygosity for different Trio variants impacts motor, social, and cognitive behaviors in distinct ways that align with clinical phenotypes in humans. Trio variants differentially impact head and brain size with corresponding changes in dendritic arbors of motor cortex layer 5 pyramidal neurons (M1 L5 PNs). Although neuronal structure was only modestly altered in the Trio variant heterozygotes, we observe significant changes in synaptic function and plasticity. We also identified distinct changes in glutamate synaptic release in +/K1431M and +/M2145T cortico-cortical synapses. The TRIO K1431M GEF1 domain has impaired ability to promote GTP exchange on Rac1, but +/K1431M mice exhibit increased Rac1 activity, associated with increased levels of the Rac1 GEF Tiam1. Acute Rac1 inhibition with NSC23766 rescued glutamate release deficits in +/K1431M variant cortex. Our work reveals that discrete NDD-associated Trio variants yield overlapping but distinct phenotypes in mice, demonstrates an essential role for Trio in presynaptic glutamate release, and underscores the importance of studying the impact of variant heterozygosity in vivo.

8.
Article in English | MEDLINE | ID: mdl-38943454

ABSTRACT

OBJECTIVE: To evaluate patients' satisfaction with opioid versus opioid-sparing postoperative analgesia in patients undergoing outpatient head and neck surgery. STUDY DESIGN: Prospective randomized trial. SETTING: Tertiary care academic hospital. METHODS: Adult patients undergoing outpatient head and neck surgery were randomly assigned to 1 of 3 analgesic regimens. First- and second-line medications were the following by group (1) Hydrocodone-acetaminophen with ibuprofen, (2) ibuprofen with hydrocodone-acetaminophen, and (3) ibuprofen with acetaminophen. Preoperative counseling was provided to patients regarding expected pain and proper medication use. Postoperative questionnaires were administered to assess satisfaction. RESULTS: One hundred three patients were enrolled in the study (mean age, 56.5 years; women, 75 [73%]). The mean satisfaction score with the pain regimen assigned was similar between the 3 groups (scale 0-10, [7.7, 8.3, 8.5, P = .46]). A similar percentage of patients in each group reported that surgery was more painful than anticipated (25%, 32%, 26%, P = .978), and a similar percentage of patients reported willingness to utilize the same analgesic regimen following future surgeries (75%, 83%, 76%, P = .682). Additional questions evaluating the side effect profile, maximum and minimum pain scores, and difficulty of recovery were not statistically different between the 3 groups. CONCLUSION: In the postoperative population for outpatient head and neck surgeries, there was no significant difference in patient satisfaction and pain control between the opioid and nonopioid arms. Providers should discuss opioid-sparing regimens preoperatively with patients and describe them as effective in providing adequate pain control without a significant impact on patient's perception of care.

9.
NPJ Precis Oncol ; 8(1): 130, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38851780

ABSTRACT

Oral squamous cell carcinoma (OSCC) biomarker studies rarely employ multi-omic biomarker strategies and pertinent clinicopathologic characteristics to predict mortality. In this study we determine for the first time a combined epigenetic, gene expression, and histology signature that differentiates between patients with different tobacco use history (heavy tobacco use with ≥10 pack years vs. no tobacco use). Using The Cancer Genome Atlas (TCGA) cohort (n = 257) and an internal cohort (n = 40), we identify 3 epigenetic markers (GPR15, GNG12, GDNF) and 13 expression markers (IGHA2, SCG5, RPL3L, NTRK1, CD96, BMP6, TFPI2, EFEMP2, RYR3, DMTN, GPD2, BAALC, and FMO3), which are dysregulated in OSCC patients who were never smokers vs. those who have a ≥ 10 pack year history. While mortality risk prediction based on smoking status and clinicopathologic covariates alone is inaccurate (c-statistic = 0.57), the combined epigenetic/expression and histologic signature has a c-statistic = 0.9409 in predicting 5-year mortality in OSCC patients.

11.
J Clin Gastroenterol ; 47(5): 461-5, 2013.
Article in English | MEDLINE | ID: mdl-23090046

ABSTRACT

BACKGROUND: Despite its high potency against hepatitis B virus (HBV), entecavir (ETV) 0.5 mg daily may not be sufficient to induce complete viral suppression in some patients with very high pretreatment viremia. It is not clear whether ETV 1.0 mg daily would have additive effect in such patients. GOALS: Our goal was to examine virologic outcome of ETV 1.0 mg daily in patients with partial response to ETV 0.5 mg daily. METHODS: We retrospectively studied 31 consecutive treatment-naive patients who were switched to ETV 1.0 mg daily after partial response [reduction of HBV DNA ≥2 log10 IU/mL but with detectable HBV DNA levels (>100 IU/mL) after 24 weeks of therapy or longer] with ETV 0.5 mg daily from January 2005 to January 2010 at 2 clinics. RESULTS: All patients were Asians and 90% had positive hepatitis B e antigen. Mean HBV DNA was 8.04±0.65 log10 IU/mL before therapy and 3.64±0.91 log10 IU/mL at the time of switch. Overall rate of complete viral suppression were 29% (n=9/31) after 24 weeks of ETV 1.0 mg daily and 22% (n=5/23) after 48 weeks. Complete viral suppression after 24 weeks with ETV 1.0 mg daily was significantly higher in patients with lower HBV DNA (<3 log10 IU/mL) at time of switch: 75% versus 5%, P<0.0001. CONCLUSIONS: The majority of patients with partial response to ETV 0.5 mg daily did not achieve complete viral suppression with the higher dose of ETV 1.0 mg daily except those with minimal residual viremia (HBV DNA <3 log10 IU/mL).


Subject(s)
Antiviral Agents/administration & dosage , Guanine/analogs & derivatives , Hepatitis B virus/drug effects , Hepatitis B, Chronic/drug therapy , Viral Load/drug effects , Viremia/drug therapy , Adult , DNA, Viral/blood , Dose-Response Relationship, Drug , Female , Guanine/administration & dosage , Hepatitis B e Antigens/blood , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Viremia/virology , Young Adult
12.
J Clin Gastroenterol ; 47(4): 367-71, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23090039

ABSTRACT

GOALS AND BACKGROUND: Besides United States population born between 1945 and 1965, screening for hepatitis C virus (HCV) is not recommended for the general US population. However, HCV may be more prevalent in certain subgroups and screening may be warranted. The goal of this study was to examine the proportion of HCV in a large sample of community Asian American patients presenting for non-liver-related complaints. STUDY: We conducted a cross-sectional study of 1246 patients tested for hepatitis C virus antibodies (anti-HCV) referred to 2 gastroenterology clinics for non-liver-related gastrointestinal reasons between January 2001 and February 2011. We determined HCV status and patient history via electronic medical record review. RESULTS: Of the 1246 study patients tested for anti-HCV, the majority were Asian (81.4%) and 29 Asian patients (2.9%) had positive anti-HCV. HCV proportion in the remaining 232 non-Asians (non-Hispanic whites and Hispanics) was 1.7%. Asians with positive anti-HCV were more likely to have had blood transfusions (31.0% vs. 6.6%, P<0.0001) or acupuncture (10.3% vs. 1.5%, P<0.0001). Of the 976 Asian patients with hepatitis B surface antigen testing, 38 (3.9%) also had detectable hepatitis B surface antigen. CONCLUSIONS: Among patients seen at community gastroenterology clinics for non-liver-related reasons, HCV proportion was 1.7% for non-Asians and 2.9% for Asians. Screening for HCV should be offered to high-risk patients presenting to gastroenterology clinics with unrelated gastrointestinal complaints.


Subject(s)
Asian/statistics & numerical data , Hepatitis C/ethnology , Acupuncture Therapy/adverse effects , Adult , Aged , Biomarkers/blood , California/epidemiology , Chi-Square Distribution , Cross-Sectional Studies , Female , Hepatitis C/diagnosis , Hepatitis C Antibodies/blood , Hispanic or Latino/statistics & numerical data , Humans , Male , Middle Aged , Prevalence , Risk Factors , Transfusion Reaction , White People/statistics & numerical data
13.
J Gastroenterol Hepatol ; 28(5): 855-60, 2013 May.
Article in English | MEDLINE | ID: mdl-23278507

ABSTRACT

BACKGROUND AND AIM: Treatment end-point of therapy for patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) includes HBeAg seroconversion, which ranges from 15% to 22% after 1 year of oral nucleos(t)ides according to clinical trials. Our goal was to determine the incidence and predictors of HBeAg seroconversion in such patients in routine clinical practice because they may differ than reported rates. METHODS: We conducted a retrospective cohort study of 333 consecutive treatment-naïve HBeAg-positive patients who were treated for CHB between 1/2000 and 6/2010 at three gastroenterology and liver clinics in the USA. Primary study end-point was HBeAg seroconversion-loss of HBeAg and antibody to HBeAg (anti-HBe) development. RESULTS: The majority of patients were Asian (96%). Median treatment duration prior to HBeAg seroconversion was 50 (range 26-52) weeks. Of the 333 study patients, 25% received lamivudine, 16% adefovir, 51% entecavir, and 8% tenofovir. HBeAg seroconversion at month 12 was 8.2%. On multivariate analysis inclusive of age, gender, and antiviral agents, independent predictors for HBeAg seroconversion at month 12 were hepatitis B virus DNA < 7.5 log10 IU/mL (hazard ratio [HR] = 2.59 [1.04-6.44]), P = 0.041) and alanine transaminase (ALT) > 1.5 × upper normal limit (HR = 2.86 [1.05-7.81], P = 0.040), but not the choice of nucleos(t)ides. CONCLUSIONS: The HBeAg seroconversion rate seen in clinical settings for oral nucleos(t)ides appears much lower than those reported in pivotal trials, especially in patients with lower ALT and higher HBV DNA levels. HBeAg-positive patients should be counseled about the high possibility of the long treatment duration required to achieve recommended treatment end-points.


Subject(s)
Hepatitis B e Antigens , Hepatitis B virus/immunology , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/immunology , Nucleotides/administration & dosage , Administration, Oral , Adult , Antiviral Agents/administration & dosage , DNA, Viral/metabolism , Drug Therapy, Combination , Endpoint Determination , Female , Hepatitis B Antibodies , Hepatitis B e Antigens/immunology , Hepatitis B virus/genetics , Hepatitis B, Chronic/epidemiology , Hepatitis B, Chronic/virology , Humans , Incidence , Male , Middle Aged , Multivariate Analysis , Retrospective Studies , Time Factors , Treatment Outcome
14.
Dig Dis Sci ; 58(11): 3342-7, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24081641

ABSTRACT

BACKGROUND AND AIMS: The Centers for Disease Control and Prevention recommend screening for hepatitis C virus (HCV) in patients with injection drug use, blood transfusion before 1992, stigmata of liver disease, or born between 1945 and 1965. The purpose of this study was to examine risk factors for HCV acquisition in Asian Americans. METHODS: This was a case-controlled study, with 471 consecutive patients testing positive for anti-HCV between January 2001 and December 2008. Controls included 471 patients with negative HCV matched at a one-to-one ratio for sex, age (±5 years), and ethnicity. RESULTS: For Asian patients, the most common risk factors were blood transfusion and acupuncture or exposure to dirty needles (27 and 20 %, respectively). On multiple logistic regression, potential predictors for a positive anti-HCV test in Asians were acupuncture or exposure to dirty needles (OR = 12.9, P < 0.0001), body tattoo (OR = 12.0, P = 0.001), and history of blood transfusion (OR = 5.7, P < 0.0001). DISCUSSION: Acupuncture and exposure to dirty needles are independent risk factors of HCV infection. Asians coming from endemic areas should be screened for HCV even when commonly-known risk factors for Western patients are not present.


Subject(s)
Asian , Hepacivirus/isolation & purification , Hepatitis C/epidemiology , Hepatitis C/etiology , Acupuncture Therapy/adverse effects , Adult , Aged , Antibodies, Viral , Case-Control Studies , Female , Hepatitis C/ethnology , Humans , Logistic Models , Male , Middle Aged , Multivariate Analysis , Risk Factors , Tattooing/adverse effects , Transfusion Reaction , United States/epidemiology
15.
J Clin Gastroenterol ; 46(10): 865-70, 2012.
Article in English | MEDLINE | ID: mdl-22941429

ABSTRACT

BACKGROUND: The primary treatment endpoint for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B is HBeAg seroconversion; however, data on the durability of response are inconsistent. GOALS: Our goal was to investigate the rate of recurrent viremia after HBeAg seroconversion and subsequent discontinuation of therapy. METHODS: We retrospectively studied 88 consecutive Asian American patients who achieved HBeAg seroconversion [loss of HBeAg and development of antibody to HBeAg (anti-HBe)] among 458 HBeAg-positive patients who received oral antiviral therapy at 3 US clinics between March 1998 and November 2010. Recurrent viremia was defined as reappearance of detectable serum hepatitis B virus DNA (>100 IU/mL) on 2 consecutive laboratory tests from previously undetectable levels. RESULTS: Antiviral medications used at the time of HBeAg seroconversion included: lamivudine (23%), adefovir (34%), entecavir (36%), tenofovir (4%), and combination therapy (3%). Antiviral therapy was continued after HBeAg seroconversion in 49 patients (group I) and discontinued in the other 39 patients after consolidation therapy [median=12 months (range, 1 to 55 mo)] (group II). No patients in group I experienced recurrent viremia, whereas 90% in group II did. Elevated alanine aminotransferase also occurred in 38% of group II patients [median peak alanine aminotransferase 249 IU/mL (range, 93 to 1070 IU/mL)]. CONCLUSIONS: Despite consolidation therapy, almost all patients who discontinued therapy after achieving HBeAg seroconversion and complete viral suppression experienced recurrent viremia, and close to half also experienced biochemical flares. HBeAg seroconversion does not seem to be a durable treatment endpoint for many patients, and they should be monitored carefully for virologic relapse and biochemical flares if antiviral therapy is withdrawn.


Subject(s)
Antibodies, Viral/blood , Antiviral Agents/therapeutic use , Hepatitis B e Antigens/immunology , Hepatitis B/drug therapy , Hepatitis B/immunology , Viremia/blood , Adult , Alanine Transaminase/blood , Consolidation Chemotherapy , DNA, Viral/blood , Female , Hepatitis B/blood , Hepatitis B virus/genetics , Hepatitis B virus/immunology , Humans , Male , Middle Aged , Recurrence , Retrospective Studies
16.
ACS Chem Biol ; 17(7): 1963-1977, 2022 07 15.
Article in English | MEDLINE | ID: mdl-35675579

ABSTRACT

The proper trafficking of eukaryotic proteins is essential to cellular function. Genetic, environmental, and other stresses can induce protein mistargeting and, in turn, threaten cellular protein homeostasis. Current methods for measuring protein mistargeting are difficult to translate to living cells, and thus the role of cellular signaling networks in stress-dependent protein mistargeting processes, such as ER pre-emptive quality control (ER pQC), is difficult to parse. Herein, we use genetically encoded peroxidases to characterize protein import into the endoplasmic reticulum (ER). We show that the ERHRP/cytAPEX pair provides good selectivity and sensitivity for both multiplexed protein labeling and for identifying protein mistargeting, using the known ER pQC substrate transthyretin (TTR). Although ERHRP labeling induces formation of detergent-resistant TTR aggregates, this is minimized by using low ERHRP expression, without loss of labeling efficiency. cytAPEX labeling recovers TTR that is mistargeted as a consequence of Sec61 inhibition or ER stress-induced ER pQC. Furthermore, we discover that stress-free activation of the ER stress-associated transcription factor ATF6 recapitulates the TTR import deficiency of ER pQC. Hence, proximity labeling is an effective strategy for characterizing factors that influence ER protein import in living cells.


Subject(s)
Endoplasmic Reticulum Stress , Endoplasmic Reticulum , Endoplasmic Reticulum/metabolism , Heat-Shock Proteins , Protein Transport , Proteostasis
17.
Medicine (Baltimore) ; 101(37): e30577, 2022 Sep 16.
Article in English | MEDLINE | ID: mdl-36123845

ABSTRACT

Endoscopic screening is used widely to minimize the rates of colorectal cancer cases and deaths. During highly virulent infectious disease pandemics such as the coronavirus disease 2019 (COVID-19) pandemic, it is essential to weigh the risks and benefits of receiving endoscopy, especially in regions with moderately high viral infection rates. An observational study was conducted to assess the number of patients seen for endoscopic procedure at 2 of our surgery centers. Reasons for their procedure were collected in addition to information regarding any positive COVID-19 cases. This study considers the rate of severe acute respiratory syndrome coronavirus 2 infection along with the number of colorectal cancer cases encountered at a community endoscopy center to suggest that the benefits of undergoing endoscopic evaluation may outweigh the risks of attending an endoscopy procedure during the COVID-19 pandemic. One of the main reasons patients underwent endoscopic procedure was for colon cancer screenings (41.9%), and 5 of 1020 patients seen during the observation period were diagnosed with cancer. Of these 1020 patients, 8 were found to have positive tests for COVID-19 within 2 to 4 weeks after their procedure.


Subject(s)
COVID-19 , Colonic Neoplasms , COVID-19/epidemiology , Colonic Neoplasms/surgery , Early Detection of Cancer , Endoscopy, Gastrointestinal , Humans , Pandemics/prevention & control
18.
Hepatology ; 52(5): 1573-80, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21038410

ABSTRACT

UNLABELLED: Hepatitis C virus (HCV) genotype is an important criteria in determining duration of therapy and predictor of sustained virologic response (SVR) to pegylated interferon (PEG IFN) and ribavirin (RBV) therapy. Optimal duration of therapy for patients with HCV genotype 6 is not known. We conducted a multicenter, open-label randomized controlled trial of patients with HCV genotype 6 at five gastroenterology clinics in the western U.S. Patients were stratified by viral load and histologic stage and assigned to receive PEG IFN-α2a 180 µg subcutaneously weekly and weight-based oral RBV 800 to 1,200 mg daily for 24 or 48 weeks. Primary outcome measurement was SVR rate by intention-to-treat analysis. From February 2005 to October 2007 a total of 60 patients (age 51 ± 10 years, 47% male, log HCVRNA 6.3 ± 1.1 IU/mL) were enrolled: 27 patients to 24 weeks and 33 patients to 48 weeks of therapy. In the 24-week and 48-week groups, 96% and 97% achieved early virologic response (P = 0.90); 89% versus 94% achieved end of therapy virologic response (P = 0.48). SVR was achieved in 70% versus 79% of patients assigned to 24 weeks versus 48 weeks (P = 0.45). Rapid virologic response (RVR) was a significant predictor of SVR in the 48-week group and trending towards significance in the 24-week group: 82% and 83% of those with RVR achieved SVR versus 33% and 29% for the 24-week and 48-week groups, respectively (P = 0.07 and P = 0.02). CONCLUSION: There was no significant difference in SVR rates in patients with HCV genotype 6 treated with PEG IFN-α2a and RBV for 24 versus 48 weeks.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/genetics , Interferon-alpha/therapeutic use , Polyethylene Glycols/therapeutic use , Adolescent , Adult , Aged , Antiviral Agents/adverse effects , California , Female , Genotype , Hepacivirus/genetics , Hepatitis C, Chronic/pathology , Humans , Interferon alpha-2 , Interferon-alpha/adverse effects , Male , Middle Aged , Polyethylene Glycols/adverse effects , Recombinant Proteins , Safety , Texas , Viral Load , Young Adult
19.
Dig Dis Sci ; 56(8): 2423-31, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21327918

ABSTRACT

BACKGROUND AND AIMS: Antiviral treatment responses for patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) are well-defined by data from registration trials but may differ from patients seen in community settings where medical adherence is usually not as strictly monitored. The goal of this study was to examine the long-term outcomes of HBeAg-negative patients in a community clinical setting. METHODS: We performed a cohort study of 189 consecutive treatment-naïve patients with CHB who were treated with either entecavir (ETV) 0.5 mg daily (n=107) or adefovir dipivoxil (ADV) 10 mg daily (n=82) from 2002 to 2009 at two community clinics. RESULTS: All patients were Asians. Both ETV and ADV cohorts had similar median baseline ALT and HBV DNA levels. By year 4, a similar proportion of ETV and ADV patients who remained on monotherapy achieved complete viral suppression (91-96%); however, more patients in the ADV cohort required alternative therapy (27 vs. 5%). No patients in the ETV cohort developed resistance while 18% of the ADV cohort did. Cumulative nonadherence rates were 10 and 12% in ADV and ETV cohorts, respectively. CONCLUSIONS: Failure to monotherapy in a community clinical setting is due to both antiviral resistance and patient nonadherence. Medication nonadherence is likely to be a more important contributor to treatment failure than antiviral resistance, especially with new anti-HBV agents such as ETV and tenofovir.


Subject(s)
Antiviral Agents/therapeutic use , Guanine/analogs & derivatives , Hepatitis B, Chronic/drug therapy , Medication Adherence/statistics & numerical data , Adenine/analogs & derivatives , Adenine/therapeutic use , Adult , Asian People/statistics & numerical data , Cohort Studies , Community Health Services/statistics & numerical data , Drug Resistance, Viral , Female , Guanine/therapeutic use , Hepatitis B e Antigens/blood , Hepatitis B e Antigens/drug effects , Hepatitis B, Chronic/blood , Humans , Male , Middle Aged , Organophosphonates/therapeutic use , Treatment Outcome , Viral Load/drug effects
20.
Front Cell Infect Microbiol ; 11: 752899, 2021.
Article in English | MEDLINE | ID: mdl-34976853

ABSTRACT

The continued proliferation of superbugs in hospitals and the coronavirus disease 2019 (COVID-19) has created an acute worldwide demand for sustained broadband pathogen suppression in households, hospitals, and public spaces. In response, we have created a highly active, self-sterilizing copper configuration capable of inactivating a wide range of bacteria and viruses in 30-60 seconds. The highly active material destroys pathogens faster than any conventional copper configuration and acts as quickly as alcohol wipes and hand sanitizers. Unlike the latter, our copper material does not release volatile compounds or leave harmful chemical residues and maintains its antimicrobial efficacy over sustained use; it is shelf stable for years. We have performed rigorous testing in accordance with guidelines from U.S. regulatory agencies and believe that the material could offer broad spectrum, non-selective defense against most microbes via integration into masks, protective equipment, and various forms of surface coatings.


Subject(s)
Anti-Infective Agents , COVID-19 , Anti-Bacterial Agents , Humans , Personal Protective Equipment , SARS-CoV-2
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