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1.
PLoS Pathog ; 20(9): e1012041, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39312588

ABSTRACT

Malaria pathogenesis and parasite multiplication depend on the ability of Plasmodium merozoites to invade human erythrocytes. Invasion is a complex multi-step process involving multiple parasite proteins which can differ between species and has been most extensively studied in P. falciparum. However, dissecting the precise role of individual proteins has to date been limited by the availability of quantifiable phenotypic assays. In this study, we apply a new approach to assigning function to invasion proteins by using optical tweezers to directly manipulate recently egressed P. falciparum merozoites and erythrocytes and quantify the strength of attachment between them, as well as the frequency with which such attachments occur. Using a range of inhibitors, antibodies, and genetically modified strains including some generated specifically for this work, we quantitated the contribution of individual P. falciparum proteins to these merozoite-erythrocyte attachment interactions. Conditional deletion of the major P. falciparum merozoite surface protein PfMSP1, long thought to play a central role in initial attachment, had no impact on the force needed to pull merozoites and erythrocytes apart, whereas interventions that disrupted the function of several members of the EBA-175 like Antigen (PfEBA) family and Reticulocyte Binding Protein Homologue (PfRH) invasion ligand families did have a significant negative impact on attachment. Deletion of individual PfEBA and PfRH ligands reinforced the known redundancy within these families, with the deletion of some ligands impacting detachment force while others did not. By comparing over 4000 individual merozoite-erythrocyte interactions in a range of conditions and strains, we establish that the PfEBA/PfRH families play a central role in P. falciparum merozoite attachment, not the major merozoite surface protein PfMSP1.


Subject(s)
Erythrocytes , Malaria, Falciparum , Optical Tweezers , Plasmodium falciparum , Humans , Antigens, Protozoan/metabolism , Erythrocytes/parasitology , Ligands , Malaria, Falciparum/parasitology , Merozoite Surface Protein 1/metabolism , Merozoites/physiology , Merozoites/metabolism , Plasmodium falciparum/growth & development , Plasmodium falciparum/physiology , Protozoan Proteins/metabolism , Protozoan Proteins/genetics
2.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Article in English | MEDLINE | ID: mdl-33975947

ABSTRACT

Malaria is a devastating infectious disease, which causes over 400,000 deaths per annum and impacts the lives of nearly half the world's population. The causative agent, a protozoan parasite, replicates within red blood cells (RBCs), eventually destroying the cells in a lytic process called egress to release a new generation of parasites. These invade fresh RBCs to repeat the cycle. Egress is regulated by an essential parasite subtilisin-like serine protease called SUB1. Here, we describe the development and optimization of substrate-based peptidic boronic acids that inhibit Plasmodium falciparum SUB1 with low nanomolar potency. Structural optimization generated membrane-permeable, slow off-rate inhibitors that prevent Pfalciparum egress through direct inhibition of SUB1 activity and block parasite replication in vitro at submicromolar concentrations. Our results validate SUB1 as a potential target for a new class of antimalarial drugs designed to prevent parasite replication and disease progression.


Subject(s)
Antimalarials/pharmacology , Boronic Acids/pharmacology , Peptides/pharmacology , Plasmodium falciparum/drug effects , Protozoan Proteins/chemistry , Subtilisins/chemistry , Antimalarials/chemical synthesis , Binding Sites , Boronic Acids/chemical synthesis , Drug Design , Erythrocytes/drug effects , Erythrocytes/parasitology , Gene Expression , Humans , Kinetics , Life Cycle Stages/drug effects , Life Cycle Stages/physiology , Models, Molecular , Molecular Docking Simulation , Peptides/chemical synthesis , Plasmodium falciparum/enzymology , Plasmodium falciparum/genetics , Plasmodium falciparum/growth & development , Protein Binding , Protein Conformation , Protein Interaction Domains and Motifs , Protozoan Proteins/antagonists & inhibitors , Protozoan Proteins/genetics , Protozoan Proteins/metabolism , Structure-Activity Relationship , Substrate Specificity , Subtilisins/antagonists & inhibitors , Subtilisins/genetics , Subtilisins/metabolism , Thermodynamics
3.
South Med J ; 116(7): 545-550, 2023 07.
Article in English | MEDLINE | ID: mdl-37400100

ABSTRACT

OBJECTIVES: To determine potential factors influencing female medical students' interest and subsequent application to orthopedics, and to evaluate female and male medical students' perceptions of women in the field of orthopedics. METHODS: An institutional review board-approved survey was distributed in March 2020 and subsequently in April 2022 to medical students in the classes of 2023 and 2024 at the University of Alabama at Birmingham Heersink School of Medicine. Study data were collected and managed using REDCap electronic data capture. An e-mail link to the REDCap survey was sent to students across the southeast region of the United States, followed by three reminder e-mails. All 25 allopathic medical schools in the southeastern United States with an Orthopedics Interest Group listed on their institution's Web site were invited to participate in the study. Nine Orthopedics Interest Group leaders interested in participating were asked to provide the researchers with a list of fourth-year medical students who attended an event hosted by that group (215). A total of 39 respondents who completed the survey were included in this study. RESULTS: Overall, the majority of students (n = 35, 90%) believed that women faced more barriers to a career in orthopedics than did men. The most significant barriers to women entering the field of orthopedics were the perceived expectations of an orthopedic surgeon (n = 34, 87%), difficulty balancing career and family (n = 28, 72%), and demanding schedule (n = 13, 33%). CONCLUSIONS: This study demonstrates that both male and female medical students believe there are significant additional barriers to success for women in the field. Study participants report that expectations set by physicians, other healthcare professionals, and patients contribute to creating greater barriers that deter medical students interested in orthopedics from ultimately applying to the specialty.


Subject(s)
Orthopedic Procedures , Orthopedics , Physicians , Students, Medical , Humans , Male , Female , United States , Orthopedics/education , Career Choice , Surveys and Questionnaires
4.
J Surg Res ; 268: 705-711, 2021 12.
Article in English | MEDLINE | ID: mdl-34487963

ABSTRACT

BACKGROUND: Clinicians and medical researchers increasingly turn to nonformal online platforms to promote research. Altmetric Attention Score (AAS) is a quantitative measurement of online influence of research in real time. The objective of this study is to determine if AAS correlates with traditional bibliometrics in the orthopaedic literature. MATERIALS AND METHODS: From the 15 orthopaedic journals with the highest impact factor, the 10 most cited articles from each journal were reviewed for 2014 -2017. For each article, AAS was collected using the Altmetric Bookmarklet application and citation count from SCOPUS. Journal impact factor was recorded using Journal Citation Reports. Statistical analysis included Pearson's and Spearman's correlation coefficients. RESULTS: A total of 600 articles were analyzed. A significant positive correlation was found between citation count and AAS for 2014 (r = 0.3188, p < 0.0001), and no correlation for 2015 (r = 0.1504, P = 0.0653), 2016 (r = 0.0087, P = 0.9157), and 2017 (r = 0.0061, P = 0.9408). There was no significant correlation between impact factor and AAS in 2014 (r = 0.4312, P = 0.1085), 2015 (r = 0.3850, P = 0.1565), 2016 (r = 0.1460, P = 0.6035) and 2017 (r = 0.0451 P = 0.8732). CONCLUSIONS: AAS and traditional bibliometrics are currently not strongly correlated in orthopaedic literature. Citations take years to accumulate and AAS represents immediate influence of an article. An amalgamation of traditional bibliometrics and AAS may prove useful in determining the short- and long-term impact and influence of publications in orthopaedics.


Subject(s)
Orthopedic Procedures , Orthopedics , Social Media , Bibliometrics , Journal Impact Factor , Research Design
5.
J Pediatr Nurs ; 60: 168-176, 2021.
Article in English | MEDLINE | ID: mdl-34004487

ABSTRACT

BACKGROUND: Pediatric delirium is common, associated with negative patient outcomes, and infrequently assessed in the ICU. Locally, pediatric delirium assessments in the cardiac PICU were infrequently documented resulting in an initiative to increase assessment documentation and implement a nurse-driven management protocol, the Bundle to Eliminate Delirium (BED). METHODS: This was a nurse-driven, quality improvement project in an eleven-bed cardiac PICU at a large academic health care facility. A pre- and postimplementation survey evaluating delirium management perceptions, knowledge, and assessment barriers was emailed to 113 nurses. Nurses received education about general delirium principles and assessment followed by weekly emails that included delirium assessment documentation rates and targeted education. Subsequently, BED education was provided via email followed by BED implementation, inclusion of BED completion rates in weekly emails, and observational audits of BED implementation. FINDINGS: 1522 delirium assessment opportunities were evaluated. Assessment documentation increased by 33%. Nurses reported greater confidence in their ability to manage delirium (P < .05 for numerous aspects of delirium care) and were less likely to report 'positive delirium assessments not acted upon' as a barrier to delirium assessment. BED implementation was inconsistent. DISCUSSION: Nursing education and feedback can increase delirium assessment rates and confidence in management but the impact of BED on these outcomes is not clear. APPLICATION TO PRACTICE: Improvement in pediatric delirium care may be obtained through a nurse-driven quality improvement project but an interprofessional approach is needed for optimal management. More studies are needed to identify effective pediatric delirium management strategies such as the BED.


Subject(s)
Delirium , Nursing Care , Child , Delirium/diagnosis , Delirium/therapy , Documentation , Humans , Intensive Care Units , Quality Improvement
6.
N Engl J Med ; 377(15): 1448-1455, 2017 10 12.
Article in English | MEDLINE | ID: mdl-29020583

ABSTRACT

BACKGROUND: Chronic hepatitis C virus (HCV) infection is more prevalent among patients who have chronic kidney disease than among those who do not have the disease. Patients with chronic kidney disease who also have HCV infection are at higher risk for progression to end-stage renal disease than those who have chronic kidney disease without HCV infection. Patients with both HCV infection and advanced chronic kidney disease have limited treatment options. METHODS: We conducted a multicenter, open-label, phase 3 trial to evaluate the efficacy and safety of treatment with the combination of the NS3/4A protease inhibitor glecaprevir and the NS5A inhibitor pibrentasvir for 12 weeks in adults who had HCV genotype 1, 2, 3, 4, 5, or 6 infection and also had compensated liver disease (with or without cirrhosis) with severe renal impairment, dependence on dialysis, or both. Patients had stage 4 or 5 chronic kidney disease and either had received no previous treatment for HCV infection or had received previous treatment with interferon or pegylated interferon, ribavirin, sofosbuvir, or a combination of these medications. The primary end point was a sustained virologic response 12 weeks after the end of treatment. RESULTS: Among the 104 patients enrolled in the trial, 52% had genotype 1 infection, 16% had genotype 2 infection, 11% had genotype 3 infection, 19% had genotype 4 infection, and 2% had genotype 5 or 6 infection. The sustained virologic response rate was 98% (102 of 104 patients; 95% confidence interval, 95 to 100). No patients had virologic failure during treatment, and no patients had a virologic relapse after the end of treatment. Adverse events that were reported in at least 10% of the patients were pruritus, fatigue, and nausea. Serious adverse events were reported in 24% of the patients. Four patients discontinued the trial treatment prematurely because of adverse events; three of these patients had a sustained virologic response. CONCLUSIONS: Treatment with glecaprevir and pibrentasvir for 12 weeks resulted in a high rate of sustained virologic response in patients with stage 4 or 5 chronic kidney disease and HCV infection. (Funded by AbbVie; ClinicalTrials.gov number, NCT02651194 .).


Subject(s)
Antiviral Agents/therapeutic use , Benzimidazoles/therapeutic use , Hepacivirus/genetics , Hepatitis C, Chronic/drug therapy , Quinoxalines/therapeutic use , Renal Insufficiency, Chronic/complications , Sulfonamides/therapeutic use , Adult , Aged , Aged, 80 and over , Aminoisobutyric Acids , Antiviral Agents/adverse effects , Benzimidazoles/adverse effects , Cyclopropanes , Drug Combinations , Female , Genotype , Hepacivirus/isolation & purification , Hepatitis C, Chronic/complications , Humans , Lactams, Macrocyclic , Leucine/analogs & derivatives , Male , Middle Aged , Proline/analogs & derivatives , Pyrrolidines , Quinoxalines/adverse effects , RNA, Viral/blood , Sulfonamides/adverse effects , Viral Load
7.
Crit Care Med ; 48(2): 185-191, 2020 02.
Article in English | MEDLINE | ID: mdl-31939786

ABSTRACT

OBJECTIVES: To determine whether best practice advisories improved sedation protocol compliance and could mitigate potential propofol-related hazardous conditions. DESIGN: Retrospective observational cohort study. SETTING: Two adult ICUs at two academic medical centers that share the same sedation protocol. PATIENTS: Adults 18 years old or older admitted to the ICU between January 1, 2016, and January 31, 2018, who received a continuous infusion of propofol. INTERVENTIONS: Two concurrent best practice advisories built in the electronic health record as a clinical decision support tool to enforce protocol compliance with triglyceride and lipase level monitoring and mitigate propofol-related hazardous conditions. MEASUREMENTS AND MAIN RESULTS: The primary outcomes were baseline and day 3 compliance with triglyceride and lipase laboratory monitoring per protocol and time to discontinuation of propofol in the setting of triglyceride and/or lipase levels exceeding protocol cutoffs. A total of 1,394 patients were included in the study cohort (n = 700 in the pre-best practice advisory group; n = 694 in the post-best practice advisory group). In inverse probability weighted regression analyses, implementing the best practice advisory was associated with a 56.6% (95% CI, 52.6-60.9) absolute increase and a 173% relative increase (risk ratio, 2.73; 95% CI, 2.45-3.04) in baseline laboratory monitoring. The best practice advisory was associated with a 34.0% (95% CI, 20.9-47.1) absolute increase and a 74% (95% CI, 1.39-2.19) relative increase in day 3 laboratory monitoring after inverse probability weighted analyses. Among patients with laboratory values exceeding protocol cutoffs, implementation of the best practice advisory resulted in providers discontinuing propofol an average of 16.6 hours (95% CI, 4.8-28.3) sooner than pre-best practice advisory. Findings from alternate analyses using interrupted time series were consistent with the inverse probability weighted analyses. CONCLUSIONS: Best practice advisories can be effectively used in ICUs to improve sedation protocol compliance and may mitigate potential propofol-related hazardous conditions. Best practice advisories should undergo continuous quality assurance and optimizations to maximize clinical utility and minimize alert fatigue.


Subject(s)
Guideline Adherence/statistics & numerical data , Hypnotics and Sedatives/administration & dosage , Practice Guidelines as Topic/standards , Propofol/administration & dosage , APACHE , Academic Medical Centers , Adult , Aged , Aged, 80 and over , Body Mass Index , Critical Care/standards , Electronic Health Records , Female , Humans , Hypnotics and Sedatives/adverse effects , Intensive Care Units/standards , Interrupted Time Series Analysis , Length of Stay , Lipase/blood , Male , Middle Aged , Propofol/adverse effects , Retrospective Studies , Triglycerides/blood
8.
J Oncol Pharm Pract ; 26(4): 912-917, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31631811

ABSTRACT

BACKGROUND: Although landmark trials in the metastatic (CLEOPATRA) and neo-adjuvant (NeoSphere; TRYPHAENA) settings identified all-grade diarrhea as a pertuzumab-associated adverse event, it was not classified as dose-limiting. In actual practice, diarrhea is often a reason for treatment modifications. OBJECTIVES: To compare the risk of pertuzumab-associated diarrhea in actual practice to the risks in randomized controlled trials. METHODS: We conducted a retrospective cohort study of HER2/neu-positive breast cancer patients who received a pertuzumab-containing regimen between January 2012 and August 2015. We calculated the risk of diarrhea with 95% confidence limits (CLs), and then used two-sample t-tests to compare the risk between trials and actual practice. RESULTS: A total of 27 patients in the study cohort received a pertuzumab-containing treatment regimen for HER2/neu-positive breast cancer. The overall risk of all-grade and severe diarrhea in actual practice was 70% (95% CLs 55-90%) and 37% (95% CLs 20-66%), respectively. No severe diarrhea was observed in the metastatic setting, and the risk of all-grade diarrhea (44%, 95% CLs 21-92%) was similar to the CLEOPATRA study (67%). The risk of all-grade diarrhea in the neo-adjuvant setting was 83% (95% CLs 68-100%), compared to 46% in the NeoSphere trial (p = 0.03). The risk of severe diarrhea (Grade 3-4) in the neo-adjuvant setting was 47% (95% CLs 27-80%) versus 6% in the NeoSphere (p < 0.0001) and 12% in the TRYPHAENA (p < 0.01) trials. CONCLUSIONS: The risk of all-grade and severe diarrhea associated with neoadjuvant pertuzumab use for HER2/neu-positive breast cancer was greater in actual practice than in trials.


Subject(s)
Antibodies, Monoclonal, Humanized/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/drug therapy , Diarrhea/chemically induced , Adult , Clinical Trials as Topic , Female , Humans , Middle Aged , Receptor, ErbB-2/analysis , Retrospective Studies
9.
Air Med J ; 39(4): 251-256, 2020.
Article in English | MEDLINE | ID: mdl-32690299

ABSTRACT

Recent coronavirus disease 2019 (COVID-19) events have presented challenges to health care systems worldwide. Air medical movement of individuals with potential infectious disease poses unique challenges and threats to crews and receiving personnel. The US Department of Health and Human Services air medical evacuation teams of the National Disaster Medical System directly supported 39 flights, moving over 2,000 individuals. Infection control precautions focused on source and engineering controls, personal protective equipment, safe work practices to limit contamination, and containment of the area of potential contamination. Source control to limit transmission distance was used by requiring all passengers to wear masks (surgical masks for persons under investigation and N95 for known positives). Engineering controls used plastic sheeting to segregate and treat patients who developed symptoms while airborne. Crews used Tyvek (Dupont Richmond, VA) suits with booties and a hood, a double layer of gloves, and either a powered air-purifying respirator or an N95 mask with a face shield. For those outside the 6-ft range, an N95 mask and gloves were worn. Safe work practices were used, which included mandatory aircraft surface decontamination, airflow exchanges, and designated lavatories. Although most patients transported were stable, to the best of our knowledge, this represents the largest repatriation of potentially contagious patients in history without infection of any transporting US Department of Health and Human Services air medical evacuation crews.


Subject(s)
Aerospace Medicine , Coronavirus Infections/prevention & control , Infection Control/methods , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Transportation of Patients/methods , Betacoronavirus , COVID-19 , China , Coronavirus Infections/therapy , Disaster Medicine , Disinfection , Equipment and Supplies , Federal Government , Health Personnel , Humans , Medical Waste Disposal , Patient Isolation/methods , Personal Protective Equipment , Personnel Staffing and Scheduling , Pneumonia, Viral/therapy , Quarantine/methods , SARS-CoV-2 , Ships , United States , United States Dept. of Health and Human Services
10.
PLoS Pathog ; 13(7): e1006453, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28683142

ABSTRACT

Egress of the malaria parasite Plasmodium falciparum from its host red blood cell is a rapid, highly regulated event that is essential for maintenance and completion of the parasite life cycle. Egress is protease-dependent and is temporally associated with extensive proteolytic modification of parasite proteins, including a family of papain-like proteins called SERA that are expressed in the parasite parasitophorous vacuole. Previous work has shown that the most abundant SERA, SERA5, plays an important but non-enzymatic role in asexual blood stages. SERA5 is extensively proteolytically processed by a parasite serine protease called SUB1 as well as an unidentified cysteine protease just prior to egress. However, neither the function of SERA5 nor the role of its processing is known. Here we show that conditional disruption of the SERA5 gene, or of both the SERA5 and related SERA4 genes simultaneously, results in a dramatic egress and replication defect characterised by premature host cell rupture and the failure of daughter merozoites to efficiently disseminate, instead being transiently retained within residual bounding membranes. SERA5 is not required for poration (permeabilization) or vesiculation of the host cell membrane at egress, but the premature rupture phenotype requires the activity of a parasite or host cell cysteine protease. Complementation of SERA5 null parasites by ectopic expression of wild-type SERA5 reversed the egress defect, whereas expression of a SERA5 mutant refractory to processing failed to rescue the phenotype. Our findings implicate SERA5 as an important regulator of the kinetics and efficiency of egress and suggest that proteolytic modification is required for SERA5 function. In addition, our study reveals that efficient egress requires tight control of the timing of membrane rupture.


Subject(s)
Antigens, Protozoan/metabolism , Erythrocytes/parasitology , Malaria, Falciparum/parasitology , Peptide Hydrolases/metabolism , Plasmodium falciparum/physiology , Animals , Antigens, Protozoan/genetics , Cell Membrane/parasitology , Erythrocytes/chemistry , Humans , Kinetics , Merozoites/chemistry , Merozoites/genetics , Merozoites/growth & development , Merozoites/physiology , Peptide Hydrolases/genetics , Plasmodium falciparum/chemistry , Plasmodium falciparum/genetics , Plasmodium falciparum/growth & development , Proteolysis
11.
J Oncol Pharm Pract ; 25(6): 1357-1365, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30124123

ABSTRACT

INTRODUCTION: Guidelines recommend pegfilgrastim for primary prophylaxis of febrile neutropenia after highly myelosuppressive chemotherapy. While deviations from guidelines could result in overuse and increased costs, underuse is also a concern and could compromise quality of care. Our objectives were to evaluate guideline adherence and quantify the extent to which physician heterogeneity may influence pegfilgrastim use. METHODS: We randomly sampled 550 patients from a retrospective cohort of those who received infusions at an academic cancer center between 1 September 2013 and 1 September 2014. Electronic medical and drug dispensing records provided information on patient characteristics, chemotherapy characteristics, prescribing physician, and pegfilgrastim administration. RESULTS: We included 154 patients treated by 25 physicians. About half of patients were male and mean age was 61.3 years. Forty (26.1%) patients had no febrile neutropenia risk factors, 62 (40.5%) had one, and 51 (33.3%) had two or more. Thirty patients (19.5%) received pegfilgrastim, of which 12 (40%) received palliative chemotherapy. Nine (60%) of 15 patients on a regimen with a febrile neutropenia risk ≥ 20% received pegfilgrastim. Pegfilgrastim use significantly varied by cancer type (p < 0.01), chemotherapy regimen (p < 0.001), and regimen febrile neutropenia risk (p < 0.001). Multivariable analysis reaffirmed the association between chemotherapy regimen febrile neutropenia risk ≥ 20% and pegfilgrastim use (odds ratio (OR) = 10.1, 95% confidence interval (CI): 1.6-62.7) and suggested that 31% (95% CI: 8%-71%) of the variation in use was attributable to physician characteristics. CONCLUSION: Pegfilgrastim was potentially overused for palliative chemotherapy and underused for chemotherapy regimens with febrile neutropenia risk ≥ 20%. Successful interventions to modify prescribing practices likely require an understanding of the relationship between specific physician characteristics and pegfilgrastim use.


Subject(s)
Febrile Neutropenia/prevention & control , Filgrastim/therapeutic use , Guideline Adherence , Neoplasms/drug therapy , Polyethylene Glycols/therapeutic use , Aged , Antineoplastic Agents/adverse effects , Febrile Neutropenia/chemically induced , Female , Granulocyte Colony-Stimulating Factor/therapeutic use , Humans , Male , Middle Aged , Practice Guidelines as Topic , Practice Patterns, Physicians' , Prescription Drug Overuse , Retrospective Studies , Risk Factors
12.
Proc Natl Acad Sci U S A ; 113(3): 740-5, 2016 Jan 19.
Article in English | MEDLINE | ID: mdl-26729880

ABSTRACT

The density of cells and neurons in the neocortex of many mammals varies across cortical areas and regions. This variability is, perhaps, most pronounced in primates. Nonuniformity in the composition of cortex suggests regions of the cortex have different specializations. Specifically, regions with densely packed neurons contain smaller neurons that are activated by relatively few inputs, thereby preserving information, whereas regions that are less densely packed have larger neurons that have more integrative functions. Here we present the numbers of cells and neurons for 742 discrete locations across the neocortex in a chimpanzee. Using isotropic fractionation and flow fractionation methods for cell and neuron counts, we estimate that neocortex of one hemisphere contains 9.5 billion cells and 3.7 billion neurons. Primary visual cortex occupies 35 cm(2) of surface, 10% of the total, and contains 737 million densely packed neurons, 20% of the total neurons contained within the hemisphere. Other areas of high neuron packing include secondary visual areas, somatosensory cortex, and prefrontal granular cortex. Areas of low levels of neuron packing density include motor and premotor cortex. These values reflect those obtained from more limited samples of cortex in humans and other primates.


Subject(s)
Neocortex/cytology , Neurons/cytology , Pan troglodytes/physiology , Aging , Animals , Cell Count , Female , Motor Cortex/cytology , Somatosensory Cortex/cytology , Visual Cortex/cytology
13.
Article in English | MEDLINE | ID: mdl-30061289

ABSTRACT

Over 2,200 patients infected with hepatitis C virus (HCV) genotypes (GT) 1 to 6, with or without cirrhosis, who were treatment naive or experienced to interferon, ribavirin, and/or sofosbuvir were treated with glecaprevir/pibrentasvir for 8, 12, or 16 weeks in eight registrational phase 2 and 3 clinical studies. High rates of sustained virologic response at 12 weeks postdosing (SVR12) were achieved with a <1% virologic failure (VF) rate. The prevalence of baseline polymorphisms (BPs) in NS3 at amino acid position 155 or 168 was low (<3%) in patients infected with GT1, GT2, GT3, GT4, and GT6, while 41.9% of the GT5-infected patients had NS3-D168E; BPs were not detected at position 156 in NS3. The prevalence of NS5A-BPs was high across genotypes, driven by common polymorphisms at amino acid position 30 or 31 in GT2, 58 in GT4, and 28 in GT6. The prevalence of NS5A T/Y93 polymorphisms was 5.5% in GT1, 4.9% in GT3, and 12.5% in GT6. Consistent with the activity of glecaprevir and pibrentasvir against most amino acid polymorphisms in vitro, BPs in NS3 and/or NS5A did not have an impact on treatment outcome for patients infected with GT1 to GT6, with the exception of treatment-experienced GT3-infected patients treated for 12 weeks, for whom a 16-week regimen of glecaprevir/pibrentasvir was required to achieve SVR12 rates of ≥95%. Among the 22 patients experiencing VF, treatment-emergent substitutions were detected in NS3 in 50% of patients and in NS5A in 82% of patients, frequently as a combination of substitutions that conferred resistance to glecaprevir and/or pibrentasvir. The glecaprevir/pibrentasvir regimen, when the recommended durations are used, allows for a pan-genotypic treatment option without the need for baseline resistance testing.


Subject(s)
Antiviral Agents/therapeutic use , Benzimidazoles/therapeutic use , Quinoxalines/therapeutic use , Sulfonamides/therapeutic use , Aminoisobutyric Acids , Cyclopropanes , Drug Resistance, Viral/genetics , Genotype , Hepatitis C, Chronic/drug therapy , Humans , Lactams, Macrocyclic , Leucine/analogs & derivatives , Polymorphism, Genetic/genetics , Proline/analogs & derivatives , Pyrrolidines , Sustained Virologic Response
14.
Article in English | MEDLINE | ID: mdl-29180522

ABSTRACT

Glecaprevir and pibrentasvir are hepatitis C virus (HCV) pangenotypic inhibitors targeting NS3/4A protease and NS5A, respectively. This once-daily, fixed-dose combination regimen demonstrated high sustained virologic response 12 weeks postdosing (SVR12) rates in CERTAIN-1 and CERTAIN-2 studies in Japanese HCV-infected patients, with a low virologic failure rate (1.2%). There were no virologic failures among direct-acting antiviral (DAA)-treatment-naive genotype 1a (GT1a) (n = 4)-, GT1b (n = 128)-, and GT2 (n = 97)-infected noncirrhotic patients treated for 8 weeks or among GT1b (n = 38)- or GT2 (n = 20)-infected patients with compensated cirrhosis treated for 12 weeks. Two of 33 DAA-experienced and 2 of 12 GT3-infected patients treated for 12 weeks experienced virologic failure. Pooled resistance analysis, grouped by HCV subtype, treatment duration, prior treatment experience, and cirrhosis status, was conducted. Among DAA-naive GT1b-infected patients, the baseline prevalence of NS3-D168E was 1.2%, that of NS5A-L31M was 3.6%, and that of NS5A-Y93H was 17.6%. Baseline polymorphisms in NS3 or NS5A were less prevalent in GT2, with the exception of the common L/M31 polymorphism in NS5A. Among DAA-experienced GT1b-infected patients (30/32 daclatasvir plus asunaprevir-experienced patients), the baseline prevalence of NS3-D168E/T/V was 48.4%, that of NS5A-L31F/I/M/V was 81.3%, that of the NS5A P32deletion was 6.3%, and that of NS5A-Y93H was 59.4%. Common baseline polymorphisms in NS3 and/or NS5A had no impact on treatment outcomes in GT1- and GT2-infected patients; the impact on GT3-infected patients could not be assessed due to the enrollment of patients infected with diverse subtypes and the limited number of patients. The glecaprevir-pibrentasvir combination regimen allows a simplified treatment option without the need for HCV subtyping or baseline resistance testing for DAA-naive GT1- or GT2-infected patients. (The CERTAIN-1 and CERTAIN-2 studies have been registered at ClinicalTrials.gov under identifiers NCT02707952 and NCT02723084, respectively.).


Subject(s)
Antiviral Agents/therapeutic use , Benzimidazoles/therapeutic use , Drug Resistance, Viral/genetics , Hepacivirus/drug effects , Hepatitis C, Chronic/drug therapy , Quinoxalines/therapeutic use , Sulfonamides/therapeutic use , Aminoisobutyric Acids , Cyclopropanes , Drug Therapy, Combination/methods , Female , Genotype , Hepacivirus/genetics , Humans , Isoquinolines/therapeutic use , Japan , Lactams, Macrocyclic , Leucine/analogs & derivatives , Liver Cirrhosis/virology , Male , Proline/analogs & derivatives , Pyrrolidines , Viral Nonstructural Proteins/genetics
15.
Article in English | MEDLINE | ID: mdl-29084747

ABSTRACT

Glecaprevir (formerly ABT-493) is a novel hepatitis C virus (HCV) NS3/4A protease inhibitor (PI) with pangenotypic activity. It inhibited the enzymatic activity of purified NS3/4A proteases from HCV genotypes 1 to 6 in vitro (half-maximal [50%] inhibitory concentration = 3.5 to 11.3 nM) and the replication of stable HCV subgenomic replicons containing proteases from genotypes 1 to 6 (50% effective concentration [EC50] = 0.21 to 4.6 nM). Glecaprevir had a median EC50 of 0.30 nM (range, 0.05 to 3.8 nM) for HCV replicons containing proteases from 40 samples from patients infected with HCV genotypes 1 to 5. Importantly, glecaprevir was active against the protease from genotype 3, the most-difficult-to-treat HCV genotype, in both enzymatic and replicon assays demonstrating comparable activity against the other HCV genotypes. In drug-resistant colony selection studies, glecaprevir generally selected substitutions at NS3 amino acid position A156 in replicons containing proteases from genotypes 1a, 1b, 2a, 2b, 3a, and 4a and substitutions at position D/Q168 in replicons containing proteases from genotypes 3a, 5a, and 6a. Although the substitutions A156T and A156V in NS3 of genotype 1 reduced susceptibility to glecaprevir, replicons with these substitutions demonstrated a low replication efficiency in vitro Glecaprevir is active against HCV with most of the common NS3 amino acid substitutions that are associated with reduced susceptibility to other currently approved HCV PIs, including those at positions 155 and 168. Combination of glecaprevir with HCV inhibitors with other mechanisms of action resulted in additive or synergistic antiviral activity. In summary, glecaprevir is a next-generation HCV PI with potent pangenotypic activity and a high barrier to the development of resistance.


Subject(s)
Antiviral Agents/pharmacology , Drug Resistance, Viral/drug effects , Hepacivirus/drug effects , Protease Inhibitors/pharmacology , Quinoxalines/pharmacology , Sulfonamides/pharmacology , Viral Nonstructural Proteins/antagonists & inhibitors , Amino Acid Substitution , Aminoisobutyric Acids , Anti-HIV Agents/pharmacology , Cyclopropanes , Drug Synergism , Genotype , HIV-1/drug effects , Hepacivirus/genetics , Humans , Lactams, Macrocyclic , Leucine/analogs & derivatives , Proline/analogs & derivatives , Replicon/drug effects , Viral Nonstructural Proteins/genetics , Virus Replication/drug effects
16.
J Med Virol ; 90(1): 109-119, 2018 01.
Article in English | MEDLINE | ID: mdl-28842997

ABSTRACT

Treatment of HCV genotype (GT) 2-infected Japanese patients with paritaprevir (NS3/4A inhibitor boosted with ritonavir) and ombitasvir (NS5A inhibitor) without ribavirin for 12 weeks in the phase 2 study M12-536, and with ribavirin for 16 weeks in phase 3 study GIFT II resulted in SVR rates of 72.2% to 91.5%. Overall, 11 out of 125 patients with GT2a and 37 out of 79 patients with GT2b infection experienced virologic failure. The prevalence of baseline polymorphisms in NS3 and NS5A and their the impact on treatment outcome, as well as the development of viral resistance in GT2-infected patients experiencing virologic failure were evaluated by HCV NS3 and NS5A population and clonal sequence analyses. Baseline polymorphisms in NS3 that confer resistance to paritaprevir were rare in both GT2a- and GT2b-infected patients, while baseline polymorphisms in NS5A that confer resistance to ombitasvir were detected in 11.2% and 14.1% of the GT2a- and GT2b-infected patients, respectively. There was no significant impact of baseline polymorphisms on treatment outcome in Japanese patients. The most common treatment-emergent substitutions at the time of virologic failure occurred at amino acid positions 168 in NS3 and 28 in NS5A in both GT2a- and GT2b-infected patients. Although there was a higher rate of virologic failure in patients with GT2b infection, the resistance analyses presented in this report support the conclusion that testing for baseline resistance-associated polymorphisms is not warranted for HCV GT2-infected patients treated with a regimen of ombitasvir/paritaprevir/ritonavir + ribavirin for 16 weeks.


Subject(s)
Anilides/therapeutic use , Antiviral Agents/therapeutic use , Carbamates/therapeutic use , Drug Resistance, Viral/genetics , Hepacivirus/drug effects , Hepatitis C, Chronic/virology , Macrocyclic Compounds/therapeutic use , Ritonavir/therapeutic use , Anilides/administration & dosage , Anilides/adverse effects , Antiviral Agents/administration & dosage , Antiviral Agents/adverse effects , Carbamates/administration & dosage , Carbamates/adverse effects , Cyclopropanes , Drug Therapy, Combination/adverse effects , Female , Genotype , Hepacivirus/genetics , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/epidemiology , Hepatitis C, Chronic/ethnology , Humans , Japan/epidemiology , Lactams, Macrocyclic , Macrocyclic Compounds/administration & dosage , Macrocyclic Compounds/adverse effects , Male , Middle Aged , Polymorphism, Genetic , Proline/analogs & derivatives , Ribavirin/administration & dosage , Ribavirin/adverse effects , Ribavirin/therapeutic use , Ritonavir/administration & dosage , Ritonavir/adverse effects , Sulfonamides , Treatment Failure , Treatment Outcome , Valine
17.
Diabetes Obes Metab ; 20(12): 2724-2732, 2018 12.
Article in English | MEDLINE | ID: mdl-29952104

ABSTRACT

AIMS: To assess whether nursing home (NH) residents with type 2 diabetes mellitus (T2D) preferentially received "T2D-friendly" (vs "T2D-unfriendly") ß-blockers after acute myocardial infarction (AMI), and to evaluate the comparative effects of the two groups of ß-blockers. MATERIALS AND METHODS: This new-user retrospective cohort study of NH residents with AMI from May 2007 to March 2010 used national data from the Minimum Data Set and Medicare system. T2D-friendly ß-blockers were those hypothesized to increase peripheral glucose uptake through vasodilation: carvedilol, nebivolol and labetalol. Primary outcomes were hospitalizations for hypoglycaemia and hyperglycaemia in the 90 days after AMI. Secondary outcomes were functional decline, death, all-cause re-hospitalization and fracture hospitalization. We compared outcomes using binomial and multinomial logistic regression models after propensity score matching. RESULTS: Of 2855 NH residents with T2D, 29% initiated a T2D-friendly ß-blocker vs 24% of 6098 without T2D (P < 0.001). For primary outcomes among residents with T2D, T2D-friendly vs T2D-unfriendly ß-blockers were associated with a reduction in hospitalized hyperglycaemia (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.21-0.97), but unassociated with hypoglycaemia (OR 2.05, 95% CI 0.82-5.10). For secondary outcomes, T2D-friendly ß-blockers were associated with a greater rate of re-hospitalization (OR 1.26, 95% CI 1.01-1.57), but not death (OR 1.06, 95% CI 0.85-1.32), functional decline (OR 0.91, 95% CI 0.70-1.19), or fracture (OR 1.69, 95% CI 0.40-7.08). CONCLUSIONS: In older NH residents with T2D, T2D-friendly ß-blocker use was associated with a lower rate of hospitalization for hyperglycaemia, but a higher rate of all-cause re-hospitalization.


Subject(s)
Adrenergic beta-Antagonists/pharmacology , Blood Glucose/drug effects , Diabetes Mellitus, Type 2/drug therapy , Hospitalization/statistics & numerical data , Myocardial Infarction/drug therapy , Aged, 80 and over , Carvedilol/pharmacology , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Female , Humans , Hyperglycemia/chemically induced , Hypoglycemia/chemically induced , Labetalol/pharmacology , Logistic Models , Male , Medicare , Myocardial Infarction/blood , Myocardial Infarction/complications , Nebivolol/pharmacology , Nursing Homes , Odds Ratio , Retrospective Studies , Treatment Outcome , United States
18.
Epilepsy Behav ; 85: 52-57, 2018 08.
Article in English | MEDLINE | ID: mdl-29908384

ABSTRACT

RATIONALE: Up to 30-50% of individuals with epilepsy have depressive symptoms, which often complicate seizure management and reduce overall quality of life. To identify and manage depressive symptoms appropriately, clinicians need standardized instruments that can accurately identify and monitor those with clinically significant depression. The self-reported 9-item Patient Health Questionnaire (PHQ-9) has been used relatively widely to screen and monitor depression in epilepsy. The rater-administered Montgomery-Asberg Depression Rating Scale (MADRS) is a rater-administered instrument widely used in depression treatment trials but less widely applied in epilepsy. This secondary analysis from 2 epilepsy self-management clinical trials compared depression severity ratings using the PHQ-9 and the MADRS instruments. METHODS: Data for this analysis were derived from pooled baseline and longitudinal data from 2 prospective epilepsy self-management randomized controlled trials (RCTs). Both RCTs assessed depression with the PHQ-9 and the MADRS. For this analysis, total depression severity scores and case classification of individuals with no/minimal, mild, moderate/moderately severe, and severe depression were assessed using both PHQ-9 and MADRS. RESULTS: The sample contained 164 individuals with epilepsy. Demographic and clinical variables between the 2 studies were generally similar. There were 107 women (64.8%), 106 African-Americans (64.2%), and 51 Whites (30.9%). Individuals had epilepsy for an average of 22.1 (SD: 15.5). Mean past 30-day seizure frequency at baseline was 3.1 (SD: 11.6). Baseline mean PHQ-9 was 10.7 (SD: 6.80) with depression severity of 32 (19.6%) not or minimally depressed, 47 (28.8%) mildly depressed, 37 (22.7%) moderately depressed, 27 (16.6%) moderately severely depressed, and 20 (12.3%) severely depressed. Baseline mean MADRS severity was 18.5 (SD: 11.3) with 30 (18.8%) not or minimally depressed, 27 (16.9%) mildly depressed, 92 (56.1%) moderately depressed, and 11 (6.9%) severely depressed. The correlation between total PHQ-9 and total MADRS was 0.843 (p < .01) although case classification by depression severity varied somewhat between the two instruments. CONCLUSIONS: Standardized measures to evaluate depression severity in people with epilepsy can help identify cases and monitor treatment. The PHQ-9 and MADRS both perform well in assessing depression in people with epilepsy although administration burden is less with PHQ-9 thus making it likely preferable for settings where time and epilepsy specialty resources are limited.


Subject(s)
Depression/diagnosis , Depressive Disorder/diagnosis , Epilepsy/complications , Quality of Life , Adult , Depression/complications , Depression/psychology , Depressive Disorder/complications , Depressive Disorder/psychology , Epilepsy/psychology , Female , Humans , Male , Middle Aged , Prospective Studies , Psychiatric Status Rating Scales , Severity of Illness Index
19.
Article in English | MEDLINE | ID: mdl-28193664

ABSTRACT

Pibrentasvir (ABT-530) is a novel and pan-genotypic hepatitis C virus (HCV) NS5A inhibitor with 50% effective concentration (EC50) values ranging from 1.4 to 5.0 pM against HCV replicons containing NS5A from genotypes 1 to 6. Pibrentasvir demonstrated similar activity against a panel of chimeric replicons containing HCV NS5A of genotypes 1 to 6 from clinical samples. Resistance selection studies were conducted using HCV replicon cells with NS5A from genotype 1a, 1b, 2a, 2b, 3a, 4a, 5a, or 6a at a concentration of pibrentasvir that was 10- or 100-fold over its EC50 for the respective replicon. With pibrentasvir at 10-fold over the respective EC50, only a small number of colonies (0.00015 to 0.0065% of input cells) with resistance-associated amino acid substitutions were selected in replicons containing genotype 1a, 2a, or 3a NS5A, and no viable colonies were selected in replicons containing NS5A from other genotypes. With pibrentasvir at 100-fold over the respective EC50, very few colonies (0.0002% of input cells) were selected by pibrentasvir in genotype 1a replicon cells while no colonies were selected in other replicons. Pibrentasvir is active against common resistance-conferring substitutions in HCV genotypes 1 to 6 that were identified for other NS5A inhibitors, including those at key amino acid positions 28, 30, 31, or 93. The combination of pibrentasvir with HCV inhibitors of other classes produced synergistic inhibition of HCV replication. In summary, pibrentasvir is a next-generation HCV NS5A inhibitor with potent and pan-genotypic activity, and it maintains activity against common amino acid substitutions of HCV genotypes 1 to 6 that are known to confer resistance to currently approved NS5A inhibitors.


Subject(s)
Antiviral Agents/pharmacology , Benzimidazoles/adverse effects , Benzimidazoles/pharmacology , Hepacivirus/drug effects , Pyrrolidines/pharmacology , Viral Nonstructural Proteins/antagonists & inhibitors , Amino Acid Substitution , Cell Line, Tumor , Drug Resistance, Viral , Hep G2 Cells , Hepacivirus/classification , Hepacivirus/genetics , Hepatitis C/drug therapy , Humans , Pyrrolidines/adverse effects , Viral Nonstructural Proteins/genetics
20.
N Engl J Med ; 370(21): 1973-82, 2014 May 22.
Article in English | MEDLINE | ID: mdl-24725237

ABSTRACT

BACKGROUND: Interferon-containing regimens for the treatment of hepatitis C virus (HCV) infection are associated with increased toxic effects in patients who also have cirrhosis. We evaluated the interferon-free combination of the protease inhibitor ABT-450 with ritonavir (ABT-450/r), the NS5A inhibitor ombitasvir (ABT-267), the nonnucleoside polymerase inhibitor dasabuvir (ABT-333), and ribavirin in an open-label phase 3 trial involving previously untreated and previously treated adults with HCV genotype 1 infection and compensated cirrhosis. METHODS: We randomly assigned 380 patients with Child-Pugh class A cirrhosis to receive either 12 or 24 weeks of treatment with ABT-450/r-ombitasvir (at a once-daily dose of 150 mg of ABT-450, 100 mg of ritonavir, and 25 mg of ombitasvir), dasabuvir (250 mg twice daily), and ribavirin administered according to body weight. The primary efficacy end point was a sustained virologic response 12 weeks after the end of treatment. The rate of sustained virologic response in each group was compared with the estimated rate with a telaprevir-based regimen (47%; 95% confidence interval [CI], 41 to 54). A noninferiority margin of 10.5 percentage points established 43% as the noninferiority threshold; the superiority threshold was 54%. RESULTS: A total of 191 of 208 patients who received 12 weeks of treatment had a sustained virologic response at post-treatment week 12, for a rate of 91.8% (97.5% CI, 87.6 to 96.1). A total of 165 of 172 patients who received 24 weeks of treatment had a sustained virologic response at post-treatment week 12, for a rate of 95.9% (97.5% CI, 92.6 to 99.3). These rates were superior to the historical control rate. The three most common adverse events were fatigue (in 32.7% of patients in the 12-week group and 46.5% of patients in the 24-week group), headache (in 27.9% and 30.8%, respectively), and nausea (in 17.8% and 20.3%, respectively). The hemoglobin level was less than 10 g per deciliter in 7.2% and 11.0% of patients in the respective groups. Overall, 2.1% of patients discontinued treatment owing to adverse events. CONCLUSIONS: In this phase 3 trial of an oral, interferon-free regimen evaluated exclusively in patients with HCV genotype 1 infection and cirrhosis, multitargeted therapy with the use of three new antiviral agents and ribavirin resulted in high rates of sustained virologic response. Drug discontinuations due to adverse events were infrequent. (Funded by AbbVie; TURQUOISE-II ClinicalTrials.gov number, NCT01704755.).


Subject(s)
Anilides/therapeutic use , Antiviral Agents/therapeutic use , Carbamates/therapeutic use , Hepacivirus , Hepatitis C, Chronic/drug therapy , Macrocyclic Compounds/therapeutic use , Ribavirin/therapeutic use , Adult , Aged , Anilides/adverse effects , Antiviral Agents/adverse effects , Carbamates/adverse effects , Cyclopropanes , Drug Resistance, Viral , Drug Therapy, Combination , Female , Genotype , Hepacivirus/genetics , Hepacivirus/isolation & purification , Hepatitis C, Chronic/complications , Humans , Lactams, Macrocyclic , Liver Cirrhosis/drug therapy , Liver Cirrhosis/etiology , Logistic Models , Macrocyclic Compounds/adverse effects , Male , Middle Aged , Proline/analogs & derivatives , Recurrence , Ribavirin/adverse effects , Sulfonamides , Valine
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