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1.
Transpl Infect Dis ; 25(2): e14055, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36929619

ABSTRACT

BACKGROUND: Transplant and hematologic malignancy patients have high Coronavirus disease 2019 (COVID-19) mortality and impaired vaccination responses. Omicron variant evades several monoclonal antibodies previously used in immunocompromised patients. Polyclonal COVID-19 convalescent plasma (CCP) may provide broader neutralizing capacity against new variants at high titers. Vaccination increases severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) titer in convalescent donors. METHODS: We conducted a retrospective chart review of hospitalized immunocompromised patients with COVID-19 who received high-titer CCP during the first omicron surge, collected from vaccinated donors within 6 months of pre-omicron COVID-19. Data on safety and outcomes were extracted. RESULTS: A total of 44 immunocompromised patients were included, 59.1% with solid organ transplant, 22.7% with hematopoietic cell transplant, 11.4% with hematologic malignancy, and 6.8% with autoimmune disease. Overall, 95% of CCP units transfused were from recently recovered and vaccinated donors and had SARS-CoV-2 antibody results 8- to 37-fold higher than the Food and Drug Administration's cutoff for high-titer CCP. There were two mild transfusion reactions. A total of 30-day mortality was 4.5%. There were no differences in 100-day mortality by underlying diagnosis, levels of immunosuppression, and timing of CCP administration. Patients with higher immunosuppression had significantly higher mean World Health Organization clinical progression scores at 30-day post-CCP compared to those with lower immunosuppression. CONCLUSIONS: CCP is a safe, globally available treatment for immunocompromised patients with COVID-19. Mortality was lower in our cohort than that of COVID-19 patients with similar immunocompromising conditions. Post-vaccine CCP with very high titers should be prioritized for study in immunocompromised patients. Post-vaccine CCP has the potential to keep pace with new variants by overcoming mutations at sufficiently high titer.


Subject(s)
COVID-19 , Hematologic Neoplasms , Hematopoietic Stem Cell Transplantation , Vaccines , Humans , COVID-19/therapy , SARS-CoV-2 , Retrospective Studies , COVID-19 Serotherapy , Immunocompromised Host , Antibodies, Viral , Hematologic Neoplasms/therapy , Antibodies, Neutralizing
2.
Int Rev Psychiatry ; 35(7-8): 645-657, 2023.
Article in English | MEDLINE | ID: mdl-38461394

ABSTRACT

Museum-based education for health professionals can lead to a variety of important learning outcomes within the domain of skills development, personal insight, perspective-taking and social advocacy. The Harvard Macy Institute's Art Museum-based Health Professions Education Fellowship was designed to develop faculty expertise in art museum-based practices, encourage scholarship, and cultivate a cohesive and supportive community of educators. The Fellowship was piloted from January to May 2019 with twelve interprofessional Fellows. Two in-person experiential sessions were held at Boston-area museums with intervening virtual learning. Fellows were introduced to a variety of approaches used in art museum-based education and developed a project for implementation at their home institution. A qualitative formative evaluation assessed immediate and 6-month post-Fellowship outcomes. Outcomes are reported in four categories: (1) Fellows' personal and professional development; (2) Institutional projects and curriculum development; (3) Community of practice and scholarly advancement of the field; and (4) Development of Fellowship model. A follow-up survey was performed four years after the conclusion of the pilot year, documenting Fellows' significant accomplishments in museum-based education, reflections on the Fellowship and thoughts on the future of the field.


Subject(s)
Fellowships and Scholarships , Museums , Humans , Curriculum , Faculty , Health Occupations
3.
Transfusion ; 62(1): 28-36, 2022 01.
Article in English | MEDLINE | ID: mdl-34677830

ABSTRACT

BACKGROUND: The reported incidence of adverse reactions following Coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) transfusion has generally been lower than expected based on the incidence of transfusion reactions that have been observed in studies of conventional plasma transfusion. This raises the concern for under-reporting of adverse events in studies of CCP that rely on passive surveillance strategies. MATERIALS AND METHODS: Our institution implemented a protocol to actively identify possible adverse reactions to CCP transfusion. In addition, we retrospectively reviewed the charts of inpatients who received CCP at Stanford Hospital between May 13, 2020 and January 31, 2021. We determined the incidence of adverse events following CCP transfusion. RESULTS: A total of 49 patients received CCP. Seven patients (14%) had an increased supplemental oxygen requirement within 4 h of transfusion completion, including one patient who was intubated during the transfusion. An additional 11 patients (total of 18, 37%) had increased oxygen requirements within 24 h of transfusion, including 3 patients who were intubated. Six patients (12%) fulfilled criteria for transfusion-associated circulatory overload (TACO). CONCLUSION: Using an active surveillance strategy, we commonly observed adverse events following the transfusion of CCP to hospitalized patients. It was not possible to definitively determine whether or not these adverse events are related to CCP transfusion. TACO was likely over-diagnosed given overlap with the manifestations of COVID-19. Nevertheless, these results suggest that the potential adverse effects of CCP transfusion may be underestimated by reports from passive surveillance studies.


Subject(s)
Blood Component Transfusion/adverse effects , COVID-19/therapy , Humans , Immunization, Passive/adverse effects , Oxygen , Plasma , Retrospective Studies , Treatment Outcome , COVID-19 Serotherapy
4.
Transfusion ; 62(9): 1860-1870, 2022 09.
Article in English | MEDLINE | ID: mdl-36084205

ABSTRACT

BACKGROUND: Washing red blood cell (RBC) units prior to transfusion is indicated for certain patients. In the United States, units stored at 1°C-6°C or transported at 1°C-10°C are available for issue up to 24 h, if not used immediately. The washing procedure commonly utilizes room temperature saline resulting in units starting out above the allowed temperature range. This leads to wastage if units are issued and returned too quickly before having a chance to equilibrate in a transport cooler. STUDY DESIGN AND METHODS: Here we performed an experimental study of washed RBC quality comparing "ideal" storage conditions in a blood bank refrigerator to a "real-world" simulation of unit transport, including holding in a transport cooler. Twelve RBC units were washed and allocated evenly into either condition. RESULTS: Measurements at 0, 1, 3, 6, 12, and 24 h post-washing revealed that placement in a transport cooler was associated with higher unit temperature prior to 12 h (p = .013) with a maximum difference of 9.3°C. Despite this difference, several measures of unit quality including extracellular potassium, pH, lactate, and free hemoglobin were indistinguishable between conditions (p = .382, .224, .286, .691, respectively). We selected half of the tested units from our irradiated inventory and confirmed increased potassium leak (p < .001) and accumulation of free hemoglobin (p = .012) in irradiated units. DISCUSSION: Washed units stored under approved transport conditions are acceptable to return to inventory up to 24 h after washing and we provide a prediction interval-based temperature threshold for rejecting these units, permitting reduced waste.


Subject(s)
Blood Preservation , Erythrocytes , Blood Preservation/methods , Blood Transfusion , Hemoglobins , Humans , Potassium
5.
Eat Weight Disord ; 26(7): 2353-2360, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33392954

ABSTRACT

PURPOSE: Emotional eating may contribute to weight gain and difficulty with weight loss. Questionnaires are currently the primary method used to identify this behaviour but there is no gold standard for detecting emotional eating, making it difficult to know which questionnaire to use for this purpose. This study assesses two questionnaires validated for assessment of emotional eating in patients with obesity, with the aim of investigating their interchangeability in the clinical setting. METHODS: 387 adult participants were recruited from the obesity treatment service at a tertiary metropolitan hospital. Responses were obtained for the 25-item Emotional Eating Scale (EES) and the 4-item coping subscale of the Palatable Eating Motives Scale (PEMS). Agreement was analysed using quadratically weighted Cohen's κ scores. Substantial agreement was defined as κ 0.61-0.80. RESULTS: The median (interquartile range) body mass index and age of participants was 42.1 kg/m2 (36.4-48.9 kg/m2) and 51.6 years (41.1-61.4 years), respectively, and 70.5% of participants were female. The EES and PEMS were found to have substantial agreement (κ 0.71; 95% CI 0.65-0.76). Agreement remained substantial when analysing responses from men (0.61; 95% CI 0.47-0.73), women (0.73; 95% CI 0.67-0.79) and post-bariatric surgery patients (0.72; 95% CI 0.62-0.82) separately. CONCLUSION: Despite focusing on different elements of emotional eating behaviour, the substantial agreement between the EES and PEMS coping subscale suggests that they identify respondents' susceptibility to emotional eating with consistency, including in people who have undergone bariatric surgery. LEVEL V: Opinions of respected authorities, based on descriptive studies, narrative reviews, clinical experience, or reports of expert committees. CLINICAL TRIAL REGISTRATION: This observational study has not been registered as a clinical trial.


Subject(s)
Emotions , Obesity , Adult , Body Mass Index , Eating , Feeding Behavior , Female , Humans , Male , Surveys and Questionnaires
6.
Horm Behav ; 124: 104752, 2020 08.
Article in English | MEDLINE | ID: mdl-32305343

ABSTRACT

Stress is a commonly reported precipitant of overeating. Understanding the relationship between stress and food intake is important, particularly in view of the increasing prevalence of obesity. The purpose of this review is to examine how stress-related eating has been defined and measured in the literature to date. There are no established diagnostic criteria or gold standards for quantification of stress-related eating. Questionnaires relying on the accuracy of self-report are the mainstay of identifying people who tend to eat in response to stress and emotions. There is a paucity of clinical research linking objective measurements of stress and appetite with self-reported eating behaviour. Limitations of the methodological approaches used and the heterogeneity between studies leave significant knowledge gaps in our understanding of the mechanism of stress related eating, and how best to identify it. These issues are discussed, and areas for further research are explored.


Subject(s)
Behavioral Research/methods , Diagnostic Techniques, Neurological , Feeding and Eating Disorders/diagnosis , Stress, Psychological/diagnosis , Appetite/physiology , Emotions , Feeding Behavior/psychology , Feeding and Eating Disorders/etiology , Humans , Hyperphagia/diagnosis , Hyperphagia/etiology , Hyperphagia/psychology , Obesity/diagnosis , Obesity/etiology , Obesity/psychology , Self Report , Stress, Psychological/complications , Surveys and Questionnaires
7.
Appetite ; 151: 104708, 2020 08 01.
Article in English | MEDLINE | ID: mdl-32283188

ABSTRACT

OBJECTIVE: The prevalence of emotional eating (EE) has increased in the general population over past decades. There is limited information on how common EE is among people seeking obesity treatment. We aimed to estimate the proportion of people with EE, and strength of associations between a predefined set of factors and EE in people referred for obesity treatment. METHODS: Cross-sectional study recruiting 387 adults from a hospital obesity service. "Emotional eating" was defined as Emotional Eating Scale (EES) score ≥25. Strength of associations were estimated by boot-strapped quantile regression analysis. Results are presented as quantile difference (QD) of EES scores at the 25th, 50th or 75th quantile, and 95% confidence intervals (95%CI). RESULTS: The study population consisted of 71% women, with a median age of 52 years (interquartile range [IQR]: 42, 61), and a median body mass index of 42 kg/m2 (IQR: 37, 49). 187 participants were managed with lifestyle modification alone, 103 with the addition of obesity pharmacotherapy, 79 with bariatric surgery, and 18 with both bariatric surgery and medications. EE was reported by an estimated 58% (95%CI: 53, 63) of participants. Factors with the largest and most consistent magnitude of association with EES differences include age, sex, use of glucagon-like peptide-1 (GLP-1) agonists, history of sleeve gastrectomy and recent bariatric surgery. CONCLUSION: Emotional eating affected more than half of people referred for obesity treatment. Age, sex, use of GLP-1 agonists, history of sleeve gastrectomy and recent bariatric surgery had the strongest associations with EE. These findings allow hypothesis generation about the underlying physiological mechanisms behind emotional eating for investigation in future research.


Subject(s)
Bariatric Surgery , Obesity, Morbid , Adult , Cross-Sectional Studies , Eating , Emotions , Female , Gastrectomy , Humans , Male , Middle Aged , Obesity/surgery , Obesity/therapy , Obesity, Morbid/surgery
9.
Eat Weight Disord ; 24(6): 1215-1219, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30778869

ABSTRACT

PURPOSE: To determine the effectiveness of Family-Based Therapy (FBT) as a treatment for Anorexia Nervosa (AN) in adolescents in a Singaporean cohort. FBT has proven effective in studies in the West, but no such study has been done in Asia. METHODS: This is a retrospective analysis of a hospital-based cohort, which included all paediatric patients (≤ 18-years) with AN treated at a tertiary hospital in Singapore between 2011 and 2017 (n = 119). The patients either received manualised FBT (n = 42) or individualized adolescent focussed therapy (non-FBT) (n = 77). Patient characteristics and time to remission were abstracted from patient records. Survival analysis was used to determine median time to remission and remission-free survival rates. Hazard ratios for remission were obtained by cox regression. RESULTS: Patients in the non-FBT group had a significantly longer time to remission compared with the FBT group after adjustment for age, gender, BMI, psychiatric comorbidity, and ethnicity (p = 0.003, HR = 2.523, 95% CI 1.37-4.64). In the FBT group, the median time to remission was 5.0 months (95% CI 3.4-6.6 months); 11 months shorter than the non-FBT group (p < 0.001, 95% CI 7.9-14.1 months). FBT group remission rates were 69% and 90% at 1 and 2 years, respectively. Non-FBT group remission rates were 30% and 57% at 1 and 2 years, respectively. CONCLUSIONS: This study confirms that FBT is an effective treatment strategy for AN in adolescents in the Asian context. FBT can shorten the illness duration, which reduces disruption to schooling and family life at this critical life stage. LEVEL OF EVIDENCE: Level IV, evidence obtained from retrospective review of data before and after the introduction of new intervention.


Subject(s)
Anorexia Nervosa/therapy , Family Therapy/methods , Adolescent , Case-Control Studies , Cohort Studies , Female , Humans , Longitudinal Studies , Male , Proportional Hazards Models , Remission Induction , Retrospective Studies , Singapore , Time Factors , Treatment Outcome
10.
Toxicol Appl Pharmacol ; 338: 204-213, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29146462

ABSTRACT

Drug-induced liver injury (DILI) has been the most frequent cause of post-marketing drug withdrawals in the last 50years. The multifactorial nature of events that precede severe liver injury in human patients is difficult to model in rodents due to a variety of confounding or contributing factors that include disease state, concurrent medications, and translational species differences. In retrospective analyses, a consistent risk factor for DILI has been the inhibition of the Bile Salt Export Pump (BSEP). One compound known for potent BSEP inhibition and severe DILI is troglitazone. The purpose of the current study is to determine if serum profiling of 19 individual bile acids by liquid chromatography-mass spectrometry (LC/MS) can detect perturbations in bile acid homeostasis in rats after acute intravenous (IV) administration of vehicle or 5, 25, or 50mg/kg troglitazone. Minimal serum transaminase elevations (approximately two-fold) were observed with no evidence of microscopic liver injury. However, marked changes in individual serum bile acids occurred, with dose-dependent increases in the majority of the bile acids profiled. When compared to predose baseline values, tauromuricholic acid and taurocholic acid had the most robust increase in serum levels and dynamic range, with a maximum fold increase from baseline of 34-fold and 29-fold, respectively. Peak bile acid increases occurred within 2hours (h) after dosing and returned to baseline values before 24h. In conclusion, serum bile acid profiling can potentially identify a mechanistic risk of clinical DILI that could be poorly detected by traditional toxicity endpoints.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 11/antagonists & inhibitors , Bile Acids and Salts/blood , Chemical and Drug Induced Liver Injury/etiology , Risk Assessment , Animals , Chromans/toxicity , Female , Male , Rats , Rats, Sprague-Dawley , Thiazolidinediones/toxicity , Troglitazone
11.
Regul Toxicol Pharmacol ; 92: 382-389, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29278695

ABSTRACT

Vismodegib (also known as GDC-0449) is a novel small molecule inhibitor of the Hedgehog (Hh) signaling pathway currently approved for the treatment of metastatic or locally advanced basal cell carcinoma (BCC) in humans. Its tumorigenic potential was assessed in dedicated carcinogenicity studies in rasH2 transgenic (Tg.rasH2) mice and Sprague Dawley (SD) rats. Tumorigenicity potential of vismodegib was identified in rats only and was limited to benign hair follicle tumors, including pilomatricomas and keratoacanthomas at exposures of ≥0.1-fold and ≥0.6-fold, respectively, of the steady-state exposure (AUC0-24h) of the recommended human dose. No malignant tumors were identified in either species. Overall, the totality of pharmacology and nonclinical safety data (lack of genotoxicity, in vitro secondary pharmacological binding, and immunoregulatory effects, and limited effects on the endocrine system) suggests that the development of the benign hair follicle tumors may be related to pharmacologically-mediated disruption of hair follicle morphogenesis, although the exact mechanism of tumorigenesis is unclear. Hair follicle tumors have not been reported in vismodegib-treated patients. The relevance of this finding in rats to patients is uncertain.


Subject(s)
Anilides/pharmacology , Carcinogenesis/drug effects , Hedgehog Proteins/metabolism , Pyridines/pharmacology , Signal Transduction/drug effects , Animals , Antineoplastic Agents/pharmacology , Carcinogenesis/metabolism , Female , Hair Follicle/drug effects , Hair Follicle/metabolism , Humans , Male , Mice , Rats , Rats, Sprague-Dawley , Skin Neoplasms/drug therapy , Skin Neoplasms/metabolism
12.
J Clin Microbiol ; 53(2): 681-3, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25428151

ABSTRACT

In the remote Japanese community of Saku, a rural town in the Nagano Prefecture, a large proportion of outpatient urinary tract infections was caused by well-recognized globally dispersed clonal lineages of uropathogenic Escherichia coli (UPEC). However, most of these strains were drug susceptible, suggesting that factors other than selection pressure account for the clonal spread of drug-susceptible UPEC.


Subject(s)
Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Urinary Tract Infections/epidemiology , Urinary Tract Infections/microbiology , Uropathogenic Escherichia coli/genetics , Uropathogenic Escherichia coli/isolation & purification , Adult , Aged , Anti-Bacterial Agents/pharmacology , Female , Genotype , Humans , Japan/epidemiology , Male , Microbial Sensitivity Tests , Middle Aged , Molecular Epidemiology , Multilocus Sequence Typing , Outpatients , Rural Population , Uropathogenic Escherichia coli/drug effects
13.
J Antimicrob Chemother ; 70(4): 971-8, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25525200

ABSTRACT

OBJECTIVES: Several observational studies have been published investigating the association between oral fluoroquinolone use and the development of retinal detachment; however, the findings are not concordant. This study is a meta-analysis of the existing literature and estimates the overall absolute risk of such an event. METHODS: Electronic databases were searched for observational studies on the association between oral fluoroquinolone and retinal detachment up to August 2014. Studies that did not meet the criteria for meta-analysis were narratively reviewed. Cases of retinal detachment during current fluoroquinolone use were also extracted for absolute risk calculation. RESULTS: Seven observational studies were included. Three (case-control and self-controlled case series studies) were eligible for meta-analysis and four (cohort studies) were narratively reviewed. The rate ratio of the case-control studies was 1.82 (95% CI 0.67-4.93), I(2) =96% and the incidence rate ratio of the self-controlled case series was 1.03 (95% CI 0.84-1.27), I(2) =36%. Three of the four cohort studies found no significant association between oral fluoroquinolone use and the development of retinal detachment. The pooled absolute risk of retinal detachment whilst on current oral fluoroquinolone treatment is estimated to be 4.85 per 1000000 prescriptions (95% CI 0.78-8.91). CONCLUSIONS: The findings of this systematic review and meta-analysis do not support an association between oral fluoroquinolone use and the development of retinal detachment. Given the low absolute risk, such an event would be rare if there were an association. The current prescribing practice for fluoroquinolones should not be altered because of a previously suggested potential risk of retinal detachment.


Subject(s)
Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/therapeutic use , Fluoroquinolones/adverse effects , Fluoroquinolones/therapeutic use , Retinal Detachment/chemically induced , Retinal Detachment/etiology , Administration, Oral , Humans
14.
Br J Clin Pharmacol ; 80(4): 855-61, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25060360

ABSTRACT

It is recognised that randomised controlled trials are not feasible for capturing rare adverse events. There is an increasing trend towards observational research methodologies using large population-based health databases. These databases offer more scope for adequate sample sizes, allowing for comprehensive patient characterisation and assessment of the associated factors. While direct causality cannot be established and confounders cannot be ignored, databases present an opportunity to explore and quantify rare events. The use of databases for the detection of rare adverse events in the following conditions, sudden death associated with attention deficit hyperactivity disorder (ADHD) treatment, retinal detachment associated with the use of fluoroquinolones and toxic epidermal necrolysis associated with drug exposure, are discussed as examples. In general, rare adverse events tend to have immediate and important clinical implications and may be life-threatening. An understanding of the causative factors is therefore important, in addition to the research methodologies and database platforms that enable the undertaking of the research.


Subject(s)
Attention Deficit Disorder with Hyperactivity/mortality , Databases, Factual , Death, Sudden/epidemiology , Drug-Related Side Effects and Adverse Reactions/epidemiology , Fluoroquinolones/adverse effects , Retinal Detachment/epidemiology , Stevens-Johnson Syndrome/epidemiology , Drug-Related Side Effects and Adverse Reactions/mortality , Humans , Retinal Detachment/chemically induced
15.
BMC Psychiatry ; 15: 95, 2015 May 01.
Article in English | MEDLINE | ID: mdl-25927845

ABSTRACT

BACKGROUND: Specialist services for the treatment of attention deficit hyperactivity disorder (ADHD) in adulthood in Hong Kong are yet to be developed. This study aims to explore the experiences of adolescents and young adults with ADHD in accessing treatment and services, coping with ADHD-related impairment, and their expectations of future treatment in Hong Kong. METHOD: Qualitative interviews were conducted with a semi-structured guide. Forty young adult patients aged between 16 and 23 were included in the study. The interview recordings were transcribed verbatim and anonymised. Data were analysed with a thematic approach based on key principles of Grounded Theory. RESULTS: Four meta-themes were developed: Accessing ADHD diagnosis and treatment services; ADHD-related impairment; Experience of ADHD treatments; and Attitudes and expectations of future ADHD treatment. The role of parents and schools were highly significant in accessing services for patients diagnosed with ADHD in childhood. In general, ADHD affected every aspect of patients' lives including academic outcome, employment, family and social relationships. Medications were the principal treatment for ADHD amongst the interviewees and were reported to be generally effective. Half of the patients received non-pharmacological treatments in childhood but these effects were reported to be temporary. There was general consensus that the needs of patients with ADHD could not be met by the current service. In particular, there is a lack of specialist service for adults with ADHD, follow-up by different clinicians, and insufficient provision of non-pharmacological treatments. CONCLUSION: The findings suggest that further development of specialist ADHD services and non-pharmacological options for young adults are essential to meet their diverse needs with a holistic approach.


Subject(s)
Adaptation, Psychological , Attention Deficit Disorder with Hyperactivity , Health Services Accessibility , Patient Preference/psychology , Social Support , Adolescent , Attention Deficit Disorder with Hyperactivity/diagnosis , Attention Deficit Disorder with Hyperactivity/psychology , Attention Deficit Disorder with Hyperactivity/therapy , Employment , Health Services Needs and Demand , Hong Kong , Humans , Male , Parents , Psychological Techniques , Schools , Work , Young Adult
16.
Proc Natl Acad Sci U S A ; 109(11): 4116-21, 2012 Mar 13.
Article in English | MEDLINE | ID: mdl-22371566

ABSTRACT

Synaptic transmission is mediated by a complex set of molecular events that must be coordinated in time and space. While many proteins that function at the synapse have been identified, the signaling pathways regulating these molecules are poorly understood. Pak5 (p21-activated kinase 5) is a brain-specific isoform of the group II Pak kinases whose substrates and roles within the central nervous system are largely unknown. To gain insight into the physiological roles of Pak5, we engineered a Pak5 mutant to selectively radiolabel its substrates in murine brain extract. Using this approach, we identified two novel Pak5 substrates, Pacsin1 and Synaptojanin1, proteins that directly interact with one another to regulate synaptic vesicle endocytosis and recycling. Pacsin1 and Synaptojanin1 were phosphorylated by Pak5 and the other group II Paks in vitro, and Pak5 phosphorylation promoted Pacsin1-Synaptojanin1 binding both in vitro and in vivo. These results implicate Pak5 in Pacsin1- and Synaptojanin1-mediated synaptic vesicle trafficking and may partially account for the cognitive and behavioral deficits observed in group II Pak-deficient mice.


Subject(s)
Nerve Tissue Proteins/metabolism , Neurons/enzymology , Neuropeptides/metabolism , Phosphoproteins/metabolism , Phosphoric Monoester Hydrolases/metabolism , Synaptic Vesicles/enzymology , p21-Activated Kinases/metabolism , Adaptor Proteins, Signal Transducing , Animals , Biological Transport , Brain/enzymology , Intracellular Signaling Peptides and Proteins , Mice , Models, Biological , Phosphorylation , Protein Binding , Substrate Specificity
17.
Biomed Chromatogr ; 29(8): 1274-9, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25677784

ABSTRACT

An LC-MS/MS method for the determination of GDC-0980 (apitolisib) concentrations in dog plasma has been developed and validated for the first time to support pre-clinical drug development. Following protein precipitation with acetonitrile, the resulting samples were analyzed using reverse-phase chromatography on a Metasil AQ column. The mass analysis was performed on a triple quadruple mass spectrometer coupled with an electrospray interface in positive ionization mode. The selected reaction monitoring transitions monitored were m/z 499.3 → 341.1 for GDC-0980 and m/z 507.3 → 341.1 for IS. The method was validated over the calibration curve range 0.250-250 ng/mL with linear regression and 1/x(2) weighting. Relative standard deviation (RSD) ranged from 0.0 to 10.9% and accuracy ranged from 93.4 to 113.6% of nominal. Stable-labeled internal standard GDC-0980-d8 was used to minimize matrix effects. This assay was used for the measurement of GDC-0980 dog plasma concentrations to determine toxicokinetic parameters after oral administration of GDC-0980 (0.03, 0.1 and 0.3 mg/kg) to beagle dogs in a GLP toxicology study. Peak concentration ranged from 3.23 to 84.9 ng/mL. GDC-0980 was rapidly absorbed with a mean time to peak concentration ranging from 1.3 to 2.4 h. Mean area under the concentration-time curve from 0 to 24 hours ranged from 54.4 to 542 ng h/mL.


Subject(s)
Bridged Bicyclo Compounds, Heterocyclic/blood , Dogs/blood , Phosphoinositide-3 Kinase Inhibitors , Pyrimidines/blood , TOR Serine-Threonine Kinases/antagonists & inhibitors , Administration, Oral , Animals , Bridged Bicyclo Compounds, Heterocyclic/administration & dosage , Female , Male , Pyrimidines/administration & dosage , Tandem Mass Spectrometry/methods , Toxicokinetics
18.
J Infect Dis ; 208(8): 1212-20, 2013 Oct 15.
Article in English | MEDLINE | ID: mdl-23852128

ABSTRACT

Even with optimal antiretroviral therapy, human immunodeficiency virus (HIV) persists in plasma, blood cells, and tissues. To develop new therapies, it is essential to know what cell types harbor residual HIV. We measured levels of HIV DNA, RNA, and RNA/DNA ratios in sorted subsets of CD4+ T cells (CCR7+, transitional memory, and effector memory) and non-CD4+ T leukocytes from blood, ileum, and rectum of 8 ART-suppressed HIV-positive subjects. Levels of HIV DNA/million cells in CCR7+ and effector memory cells were higher in the ileum than blood. When normalized by cell frequencies, most HIV DNA and RNA in the blood were found in CCR7+ cells, whereas in both gut sites, most HIV DNA and RNA were found in effector memory cells. HIV DNA and RNA were observed in non-CD4+ T leukocytes at low levels, particularly in gut tissues. Compared to the blood, the ileum had higher levels of HIV DNA and RNA in both CD4+ T cells and non-CD4+ T leukocytes, whereas the rectum had higher HIV DNA levels in both cell types but lower RNA levels in CD4+ T cells. Future studies should determine whether different mechanisms allow HIV to persist in these distinct reservoirs, and the degree to which different therapies can affect each reservoir.


Subject(s)
DNA, Viral/metabolism , HIV Infections/drug therapy , HIV Infections/virology , HIV/genetics , Lymphocyte Subsets/virology , RNA, Viral/metabolism , Adult , Anti-Retroviral Agents/therapeutic use , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/virology , DNA, Viral/analysis , DNA, Viral/blood , Flow Cytometry , HIV/isolation & purification , HIV Infections/blood , HIV Infections/immunology , Humans , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/virology , Male , Middle Aged , RNA, Viral/analysis , RNA, Viral/blood , Statistics, Nonparametric , Viral Load
19.
Reprod Toxicol ; 123: 108526, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38141866

ABSTRACT

Zinpentraxin alfa is a recombinant human pentraxin-2 (PTX-2) developed for the treatment of various fibrotic diseases with the hypothesis that supplementing endogenous PTX-2 levels through intravenous administration should increase its regulatory capacity in circulation and at the site of disease, thereby promoting healing and reducing fibrosis. Zinpentraxin alfa has been studied in various clinical trials, particularly in patients with idiopathic pulmonary fibrosis, where it has demonstrated efficacy in slowing decline in lung function in a phase 2 study. In the present investigation, we summarize findings from 14-day repeat-dose toxicity studies in rats and cynomolgus monkeys supporting early clinical development of zinpentraxin alfa. In addition, we also describe the findings from the embryo-fetal developmental (EFD) studies conducted in rats and rabbits, since the intended fibrosis patient population may include patients of childbearing potential. Zinpentraxin alfa was well tolerated by rats and monkeys in general toxicity studies with no treatment-related adverse effects, as well as by pregnant rats over the same dose range in a definitive EFD study. In contrast, substantial toxicity was observed in a rabbit dose-range-finder EFD study. Zinpentraxin alfa was poorly tolerated by pregnant rabbits and effects on the dams correlated with post-implantation fetal losses. The disparate effects of zinpentraxin alfa on embryo-fetal development between the two species suggests a potential unknown biological function of PTX-2 in pregnancy in the rabbit, which may be relevant to humans. Our findings warrant the consideration for highly effective contraceptive measures to avoid pregnancy in patients enrolled in clinical studies with zinpentraxin alfa.


Subject(s)
Fetus , Pregnancy , Female , Rats , Humans , Animals , Rabbits , Fibrosis
20.
AAPS J ; 26(1): 16, 2024 01 24.
Article in English | MEDLINE | ID: mdl-38267613

ABSTRACT

Immunogenicity assessment is an essential part of biotherapeutic drug development. While the immune response in animals is not always representative of the human immune response, immunogenicity data obtained in animal models is still informative for the evaluation of drug exposure and safety. The most common assay format used for the detection of anti-drug antibodies (ADAs) in preclinical and clinical studies is the bridging format. The advantage of this method is that it can detect all antibody isotypes generated against the therapeutic. However, the method development can be time-consuming and labor-intensive, due to the need for labeling of the drug which is used both as capture and detection. Various generic ADA assays have been successfully implemented to overcome these disadvantages and to enable faster assay development timelines to support nonclinical toxicology studies. Here, we describe the challenges in the development of an assay to detect antibodies to zinpentraxin alfa, a recombinant human pentraxin-2, in rabbit and rat toxicology studies. Our initial efforts to develop a bridging assay failed, prompting us to develop a method adapted from generic assay formats to detect anti-zinpentraxin alfa antibodies in the serum of different species with minimal optimization. However, while the general assay format remained similar, assay reagents were adapted between the different species, resulting in the development of two distinct assays for the detection of ADAs in rat and rabbit. Here, we share the final development/validation data and the immunogenicity study results. Our work highlights the need for the evaluation of alternate assay formats when evaluating novel drug modalities.


Subject(s)
Antibodies , Biological Assay , Humans , Animals , Rabbits , Rats , Drug Development , Drugs, Generic , Models, Animal
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