Eligibility for antiamyloid treatment: preparing for disease-modifying therapies for Alzheimer's disease.

BACKGROUND: Disease-modifying therapies (DMTs) for Alzheimer's disease (AD) have early evidence of efficacy. Widespread delivery of DMTs will require major service reconfiguration. Treatment pathways will need to include triaging for eligibility, regular infusions and baseline and follow-up MRI scanning. A critical step in planning is provision of real-world estimates of patients likely to be eligible for triaging, but these are challenging to obtain. METHODS: We performed a retrospective service evaluation of patients attending five memory services across North and East London and a national specialist cognitive disorders service. We examined the likely proportion of patients who would (1) be referred for triaging for DMTs and (2) potentially be suitable for treatments. RESULTS: Data from a total of 1017 patients were included, 517 of whom were seen in community memory services and 500 in a specialist clinic. In the memory services, 367/517 (71%) were diagnosed with possible AD. After exclusions of those in whom cognitive and frailty scores, MRI contraindications or anticoagulant use indicated they would be unlikely to be suitable, an estimated 32% would be eligible for triaging. In the specialist cognitive clinic, where additional investigations are available, 14% of those seen (70/500) would be potentially eligible for treatment. CONCLUSIONS: While a sizeable proportion of patients attending memory clinics may be referred for triaging for DMTs for AD, only a minority are likely to be suitable for these, as demonstrated in patients seen in specialist cognitive services. This will need to be considered when designing pathways for DMT delivery.

A Single-Center Experience with a Shear-Thinning Conformable Embolic.

The purpose of this study was to evaluate the technical success, effectiveness, and safety of transarterial embolization for acute bleeding management with a shear-thinning conformable embolic. This single-center retrospective study evaluated outcomes after embolization using Obsidio conformable embolic (OCE). Technical success was defined as performing transarterial embolization within the target vessel to complete stasis of antegrade flow. Treatment effectiveness was defined as cessation of bleeding for patients. Eleven patients underwent 11 embolization procedures. A total of 16 arteries were embolized. Indications for embolization were spontaneous tumor bleeding (6/11), hematuria (2/11), active duodenal bleeding (1/11), portal hypertensive bleeding (1/11), and rectus sheath hematoma (1/11). The technical success rate was 100%. The median vessel diameter was 2 mm (range, 1-3 mm). There were no adverse events or off-target embolization. OCE demonstrated technical success and treatment effectiveness with a short-term safety profile for transarterial embolization interventions.

Rare Congenital Upper Lip Pit.

Congenital lip pits are characterized by sinuses or fistulas in the lips that can occur in isolation or as part of a genetic disorder. A 6-year-old girl with a right upper lip lesion present at birth presented with recurrent swelling and occasional erythema. Examination revealed a mildly swollen punctum at the right upper wet/dry vermillion with expressible serous drainage. There were no other phenotypic or cognitive concerns. The lesion was surgically excised using vertical wedge resection. The postoperative course showed well well-healed incision. The pathology report confirmed a lip pit. The family was referred to genetics for further evaluation. Van der Woude syndrome (VWS) is a genetic disorder associated with abnormal development of the paramedian lip. Most congenital lip pits are primarily found on the lower lips, with paramedian lip pits being the most common. Upper lateral lip pits with or without accompanying lip pits are considerably rarer. Though VWS is commonly associated with mutations in the interferon regulatory factor 6 or grainyhead-like protein 3 genes, ~25% of affected individuals lack an identified genetic etiology. A high index of suspicion for VWS is warranted if lip pits are present in the absence of other phenotypic abnormalities and should prompt genetic testing for interferon regulatory factor 6 and grainyhead-like protein 3 mutations. Multidisciplinary teams should consider patient self-esteem, quality of life, and potential family planning when deciding on surgical intervention for lip pits. Surgical management of pits should entail tissue-preserving techniques such as vertical wedge resection and inverted T-lip reduction to prevent whistle-lip deformity.

Old drugs, new uses: Drug repurposing in hematological malignancies.

Discovery and development of novel anti-cancer drugs are expensive and time consuming. Systems biology approaches have revealed that a drug being developed for a non-cancer indication can hit other targets as well, which play critical roles in cancer progression. Since drugs for non-cancer indications would have already gone through the preclinical and partial or full clinical development, repurposing such drugs for hematological malignancies would cost much less, and drastically reduce the development time, which is evident in case of thalidomide. Here, we have reviewed some of the drugs for their potential to repurpose for treating the hematological malignancies. We have also enlisted resources that can be helpful in drug repurposing.

Care in the time of COVID-19: impact on the diagnosis and treatment of breast cancer in a large, integrated health care system.

PURPOSES: To delineate operational changes in Kaiser Permanente Northern California breast care and evaluate the impact of these changes during the initial COVID-19 Shelter-in-Place period (SiP, 3/17/20-5/17/20). METHODS: By extracting data from institutional databases and reviewing electronic medical charts, we compared clinical and treatment characteristics of breast cancer patients diagnosed 3/17/20-5/17/20 to those diagnosed 3/17/19-5/17/2019. Outcomes included time from biopsy to consultation and treatment. Comparisons were made using Chi-square or Wilcoxon rank-sum tests. RESULTS: Fewer new breast cancers were diagnosed in 2020 during the SiP period than during a similar period in 2019 (n = 247 vs n = 703). A higher percentage presented with symptomatic disease in 2020 than 2019 (78% vs 37%, p < 0.001). Higher percentages of 2020 patients presented with grade 3 (37% vs 25%, p = 0.004) and triple-negative tumors (16% vs 10%, p = 0.04). A smaller percentage underwent surgery first in 2020 (71% vs 83%, p < 0.001) and a larger percentage had neoadjuvant chemotherapy (16% vs 11%, p < 0.001). Telehealth utilization increased from 0.8% in 2019 to 70.0% in 2020. Times to surgery and neoadjuvant chemotherapy were shorter in 2020 than 2019 (19 vs 26 days, p < 0.001, and 23 vs 28 days, p = 0.03, respectively). CONCLUSIONS: During SiP, fewer breast cancers were diagnosed than during a similar period in 2019, and a higher proportion presented with symptomatic disease. Early-stage breast cancer diagnoses decreased, while metastatic cancer diagnoses remained similar. Telehealth increased significantly, and times to treatment were shorter in 2020 than 2019. Our system continued to provide timely breast cancer treatment despite significant pandemic-driven disruption.

Satisfaction With Clinician-Led Germline Genetic Counseling in Patients With Prostate Cancer.

PURPOSE: Indications for germline testing in prostate cancer patients have expanded substantially over the past decade. With a near-universal shortage of genetic counselors and increasing demand, increased access to genetic counseling is crucial. We sought to prospectively implement and assess a clinician-led approach to genetic counseling and testing. MATERIALS AND METHODS: Patients with metastatic or localized prostate cancer meeting National Comprehensive Cancer Network® criteria for consideration of genetic testing were offered pre-test genetic counseling by their urologist or medical oncologist as part of their routine clinical care and concurrently approached for enrollment in the Germline Genetics in Prostate Cancer Study. Consented patients filled out a post-counseling survey using validated instruments to assess the quality of counseling. For patients who elected to undergo genetic testing, an additional validated questionnaire was completed following disclosure of results. The primary outcome was the proportion of patients undergoing testing, with a target >60% of patients. The secondary outcome was overall satisfaction with counseling, with a target >85% of patients. RESULTS: A total of 275 patients enrolled, and 203 patients elected to undergo genetic testing. Post-counseling surveys were obtained from 265 patients, and post-genetic testing surveys were obtained from 132 patients. Patient satisfaction was high, with 98% of patients reporting being satisfied with the overall quality of pre-test counseling, and 74% of patients elected to undergo genetic testing. CONCLUSIONS: These results support the effectiveness of clinician-led genetic counseling in prostate cancer. With clinician training, this approach can be utilized to expand access to appropriate germline genetic testing.

Outcomes of Radiofrequency Ablation Compared to Liquid Nitrogen Spray Cryotherapy for the Eradication of Dysplasia in Barrett's Esophagus.

INTRODUCTION: Current guidelines recommend endoscopic eradication therapy (EET) for Barrett's esophagus (BE) with dysplasia and intramucosal adenocarcinoma using either radiofrequency ablation (RFA) or liquid nitrogen spray cryotherapy (LNSC). The aims of this multicenter study are to compare the rate and number of treatment sessions of RFA vs. LNSC to achieve CE-D and CE-IM and assess outcomes for those who switched therapy. METHODS: This is a retrospective cohort study of patients with BE undergoing EET. Demographics, baseline variables, endoscopy details, and histology information were abstracted. RESULTS: One hundred and sixty-two patients were included in this study with 100 patients in the RFA group and 62 patients in the LNSC group. The rate of CE-D and CE-IM did not differ between the RFA group and LNSC group (81% vs. 71.0%, p = 0.14) and (64% vs. 66%, p = 0.78), respectively. The number of sessions to achieve CE-D and CE-IM was higher with LNSC compared to RFA (4.2 vs. 3.2, p = 0.05) and (4.8 vs. 3.5, p = 0.04), respectively. The likelihood of developing recurrent dysplasia was higher among patients who did not achieve CE-IM (12%) compared to those who did achieve CE-IM (4%), p = 0.04. Similar findings were found in those who switched treatment modalities. DISCUSSION: EET is highly effective in eradication of Barrett's associated dysplasia and neoplasia. Both RFA and LNSC achieved similar rates of CE-D and CE-IM although LNSC required more sessions. Also, achievement of CE-IM was associated with less recurrence rates of dysplasia.

Syndecan-1 and Glypican-1 Knockout Alters Body Water Balance and Urine Response to Fluid Challenge in Mice.

Syndecan-1 (Sdc-1) and glypican-1 (Gpc-1) are 2 important proteoglycans found in the glycocalyx and believed to govern transvascular distribution of fluid and protein. In this translational study, we assessed Sdc-1 and Gpc-1 knockout (KO) on whole body water balance after an intravenous volume challenge. Sdc-1 and Gpc-1 KO mice had higher starting blood water content versus strain-matched controls. Sdc-1 KO mice exhibited a significantly higher diuretic response (87%; p < 0.05), higher excreted volume/infusion volume ratio (p < 0.01), higher extravascular/infused ratio, and greater tissue water concentration (60 vs. 52%). Collectively, these suggest differences in kidney response and greater fluid efflux from peripheral vessels. The CD1 strain and Gpc-1 KO had a 2-3-fold larger urine output relative to C57 strain, but Gpc-1 KO reduced the excreted/infused ratio relative to controls (p < 0.01) and they maintained plasma dilution longer. Thus, genetic KO of Sdc-1 and Gpc-1 resulted in markedly different phenotypes. This work establishes the feasibility of performing fluid balance studies in mice.

Finding Druggable Sites in Proteins Using TACTICS.

Structure-based drug discovery efforts require knowledge of where drug-binding sites are located on target proteins. To address the challenge of finding druggable sites, we developed a machine-learning algorithm called TACTICS (trajectory-based analysis of conformations to identify cryptic sites), which uses an ensemble of molecular structures (such as molecular dynamics simulation data) as input. First, TACTICS uses k-means clustering to select a small number of conformations that represent the overall conformational heterogeneity of the data. Then, TACTICS uses a random forest model to identify potentially bindable residues in each selected conformation, based on protein motion and geometry. Lastly, residues in possible binding pockets are scored using fragment docking. As proof-of-principle, TACTICS was applied to the analysis of simulations of the SARS-CoV-2 main protease and methyltransferase and the Yersinia pestis aryl carrier protein. Our approach recapitulates known small-molecule binding sites and predicts the locations of sites not previously observed in experimentally determined structures. The TACTICS code is available at https://github.com/Albert-Lau-Lab/tactics_protein_analysis.

Endoscopic resection reduces morbidity when compared to surgery in veterans with large and complex colorectal polyps.

INTRODUCTION: Data supporting endoscopic resection (ER) over surgical resection (SR) for large and complex polyps come from high-volume centers. The aim of this study was to determine whether these favorable outcomes can be replicated among endoscopists at tertiary Veterans Affairs Medical Centers (VAMCs) who perform 25 to 30 ER cases a year. METHODS: Patients with adenomatous polyps or intra-mucosal cancers ≥ 2 cm in size who underwent ER or SR were identified from prospectively maintained databases at the 2 tertiary VAMCs in Veterans Integrated Service Network 6 (VISN6). The primary outcome was the rate of serious complications in the ER and SR groups. RESULTS: 310 ER and 81 SR patients met the inclusion criteria. ER was successful in 97% of all polyps, and 93% of polyps ≥ 4 cm. The rate of serious complications was significantly lower with ER compared to SR (0.6% vs. 22%, p = 0.00001). These findings persisted even after limiting the analysis to polyps ≥ 4 cm and after propensity score matching. If all ER patients had instead undergone laparoscopic surgery, the estimated risk of a serious complication was still higher than ER for all patients (8% vs. 0.6%, p < 0.0001) but not significantly higher for polyps ≥ 4 cm (8% vs 2%, p = 0.17). CONCLUSIONS: This study documents high success rates for ER in veterans with colorectal polyps ≥ 2 cm and ≥ 4 cm. When compared to a historical cohort of surgical patients, a strategy of attempting ER first reduced morbidity. A randomized trial is warranted to compare ER to laparoscopic surgery for polyps ≥ 4 cm.

Tyrp1 Mutant Variants Associated with OCA3: Computational Characterization of Protein Stability and Ligand Binding.

Oculocutaneous albinism type 3 (OCA3) is an autosomal recessive disorder caused by mutations in the TYRP1 gene. Tyrosinase-related protein 1 (Tyrp1) is involved in eumelanin synthesis, catalyzing the oxidation of 5,6-dihydroxyindole-2-carboxylic acid oxidase (DHICA) to 5,6-indolequinone-2-carboxylic acid (IQCA). Here, for the first time, four OCA3-causing mutations of Tyrp1, C30R, H215Y, D308N, and R326H, were investigated computationally to understand Tyrp1 protein stability and catalytic activity. Using the Tyrp1 crystal structure (PDB:5M8L), global mutagenesis was conducted to evaluate mutant protein stability. Consistent with the foldability parameter, C30R and H215Y should exhibit greater instability, and two other mutants, D308N and R326H, are expected to keep a native conformation. SDS-PAGE and Western blot analysis of the purified recombinant proteins confirmed that the foldability parameter correctly predicted the effect of mutations critical for protein stability. Further, the mutant variant structures were built and simulated for 100 ns to generate free energy landscapes and perform docking experiments. Free energy landscapes formed by Y362, N378, and T391 indicate that the binding clefts of C30R and H215Y mutants are larger than the wild-type Tyrp1. In docking simulations, the hydrogen bond and salt bridge interactions that stabilize DHICA in the active site remain similar among Tyrp1, D308N, and R326H. However, the strengths of these interactions and stability of the docked ligand may decrease proportionally to mutation severity due to the larger and less well-defined natures of the binding clefts in mutants. Mutational perturbations in mutants that are not unfolded may result in allosteric alterations to the active site, reducing the stability of protein-ligand interactions.

Characterization of Temperature-Dependent Kinetics of Oculocutaneous Albinism-Causing Mutants of Tyrosinase.

Human tyrosinase (Tyr) is a glycoenzyme that catalyzes the first and rate-limiting step in melanin production, and its gene (TYR) is mutated in many cases of oculocutaneous albinism type 1 (OCA1). The mechanisms by which individual mutations contribute to the diverse pigmentation phenotype in patients with OCA1 have only began to be examined and remain to be delineated. Here, we analyze the temperature-dependent kinetics of wild-type Tyr (WT) and two OCA1B mutant variants (R422Q and P406L) using Michaelis-Menten and Van't Hoff analyses. Recombinant truncated human Tyr proteins (residues 19-469) were produced in the whole insect Trichoplusia Ni larvae. Proteins were purified by a combination of affinity and size-exclusion chromatography. The temperature dependence of diphenol oxidase protein activities and kinetic parameters were measured by dopachrome absorption. Using the same experimental conditions, computational simulations were performed to assess the temperature-dependent association of L-DOPA and Tyr. Our results revealed, for the first time, that the association of L-DOPA with R422Q and P406L followed by dopachrome formation is a complex reaction supported by enthalpy and entropy forces. We show that the WT has a higher turnover number as compared with both R422Q and P406L. Elucidating the kinetics and thermodynamics of mutant variants of Tyr in OCA1B helps to understand the mechanisms by which they lower Tyr catalytic activity and to discover novel therapies for patients.

Development of a simple high performance liquid chromatography (HPLC)/evaporative light scattering detector (ELSD) method to determine Polysorbate 80 in a pharmaceutical formulation.

The amount of polysorbate 80 in pharmaceutical formulations affects the product quality and efficacy. A reliable test method is required to quantify the amount of Polysorbate 80 present in the drug product formulations. The test method for the determination of Polysorbate 80 may be used during process development and final product quality assessment. A simple, fast and efficient quantitative method, making use of HPLC-ELSD and a C18 column without sample pretreatment was developed. The developed method demonstrated specificity to polysorbate 80 with high precision as indicated by percent relative standard deviation (%RSD) of 3.0% for six determinations. The accuracy of this method for the determination of polysorbate 80 in a pharmaceutical formulation was demonstrated with an overall recovery of 94.9%.

Multiplexed autoantigen microarrays identify HLA as a key driver of anti-desmoglein and -non-desmoglein reactivities in pemphigus.

Patients with pemphigus vulgaris (PV) harbor antibodies reactive against self-antigens expressed at the surface of keratinocytes, primarily desmoglein (Dsg) 3 and, to a lesser extent, Dsg1. Conventionally, only antibodies targeting these molecules have been thought to contribute to disease pathogenesis. This notion has been challenged by a growing pool of evidence that suggests that antibodies toward additional targets may play a role in disease. The aims of this study were to (i) establish high-throughput protein microarray technology as a method to investigate traditional and putative autoantibodies (autoAbs) in PV and (ii) use multiplexed protein array technology to define the scope and specificity of the autoAb response in PV. Our analysis demonstrated significant IgG reactivity in patients with PV toward the muscarinic acetylcholine receptor subtypes 3, 4, and 5 as well as thyroid peroxidase. Furthermore, we found that healthy first- and second-degree relatives of patients with PV express autoAbs toward desmoglein and non-Dsg targets. Our analysis also identified genetic elements, particularly HLA, as key drivers of autoAb expression. Finally, we show that patients with PV exhibit significantly reduced IgM reactivity toward disease-associated antigens relative to controls. The use of protein microarrays to profile the autoAb response in PV advanced the current understanding of disease and provided insight into the complex relationship between genetics and disease development.

Lactated Ringer's solution in combination with rectal indomethacin for prevention of post-ERCP pancreatitis and readmission: a prospective randomized, double-blinded, placebo-controlled trial.

BACKGROUND AND AIMS: Prospective data have shown the benefit of rectal indomethacin (IND) for preventing post-ERCP pancreatitis (PEP). A recent pilot study demonstrated a lower incidence of PEP after an 8-hour lactated Ringer's solution (LR) infusion. The aim of this study was to evaluate the efficacy of IND with or without bolus LR in patients at high-risk for PEP. METHODS: In this randomized, double-blinded, placebo-controlled trial we assigned patients to standard normal saline solution (NS) + placebo, NS + IND, LR + placebo, or LR + IND. Each liter of fluid infusion was completed within 30 minutes. Patients were determined high-risk based established criterion and excluded if they had pancreatitis, contraindications to IND, or signs of volume overload. Our primary outcome was PEP, defined by standardized criterion. Our secondary outcomes were severe acute pancreatitis, localized adverse events, death, length of stay, and readmission. RESULTS: Our sample consisted of 192 patients (48 per group) who completed follow-up at 24 hours and at 30 days post-ERCP. All patients had at least 1 high-risk criterion for PEP, and 56% had >1. PEP occurred in 3 patients (6%) in the LR + IND versus 10 (21%) in the NS + placebo group (P = .04). Readmission rates were lower in the LR + IND group (1 [2%]) versus the NS + placebo group (6 [13%]; P = .03). No differences were found between the other study groups. There was 1 case of severe pancreatitis (NS + IND) and 1 case of pseudocyst (LR + IND). CONCLUSIONS: In patients at high risk for PEP, LR + IND reduced the incidence of PEP and readmission rates compared with NS + placebo. (Clinical trial registration number: NCT02641561.).

Functional diversification of hsp40: distinct j-protein functional requirements for two prions allow for chaperone-dependent prion selection.

Yeast prions are heritable amyloid aggregates of functional yeast proteins; their propagation to subsequent cell generations is dependent upon fragmentation of prion protein aggregates by molecular chaperone proteins. Mounting evidence indicates the J-protein Sis1 may act as an amyloid specificity factor, recognizing prion and other amyloid aggregates and enabling Ssa and Hsp104 to act in prion fragmentation. Chaperone interactions with prions, however, can be affected by variations in amyloid-core structure resulting in distinct prion variants or 'strains'. Our genetic analysis revealed that Sis1 domain requirements by distinct variants of [PSI+] are strongly dependent upon overall variant stability. Notably, multiple strong [PSI+] variants can be maintained by a minimal construct of Sis1 consisting of only the J-domain and glycine/phenylalanine-rich (G/F) region that was previously shown to be sufficient for cell viability and [RNQ+] prion propagation. In contrast, weak [PSI+] variants are lost under the same conditions but maintained by the expression of an Sis1 construct that lacks only the G/F region and cannot support [RNQ+] propagation, revealing mutually exclusive requirements for Sis1 function between these two prions. Prion loss is not due to [PSI+]-dependent toxicity or dependent upon a particular yeast genetic background. These observations necessitate that Sis1 must have at least two distinct functional roles that individual prions differentially require for propagation and which are localized to the glycine-rich domains of the Sis1. Based on these distinctions, Sis1 plasmid-shuffling in a [PSI+]/[RNQ+] strain permitted J-protein-dependent prion selection for either prion. We also found that, despite an initial report to the contrary, the human homolog of Sis1, Hdj1, is capable of [PSI+] prion propagation in place of Sis1. This conservation of function is also prion-variant dependent, indicating that only one of the two Sis1-prion functions may have been maintained in eukaryotic chaperone evolution.

Inhibition of Aggregation of Mutant Huntingtin by Nucleic Acid Aptamers In Vitro and in a Yeast Model of Huntington's Disease.

Elongated polyglutamine stretch in mutant huntingtin (mhtt) correlates well with the pathology of Huntington's disease (HD). Inhibition of aggregation of mhtt is a promising strategy to arrest disease progression. In this work, specific, high-affinity RNA aptamers were selected against monomeric mhtt (51Q-htt). Some of them inhibited its aggregation in vitro by stabilizing the monomer. They also recognized 103Q-htt but not 20Q-htt (nonpathogenic length). Inhibition of aggregation corresponded with reduced leakage of a fluorescent probe from liposomes and diminished oxidative stress in RBCs. The presence of aptamers was able to rescue the sequestration of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) by aggregated mhtt. Some of the aptamers were able to enhance the partitioning of mhtt in the soluble fraction in a yeast model of HD. They were also able to rescue endocytotic defect due to aggregation of mhtt. The beneficial effect of a combination of aptamers was enhanced with improvement in cell survival. Since HD is a monogenic autosomal dominant disorder, aptamers may be developed as a viable strategy to slow down the progress of the disease. Since they are nonimmunogenic and nontoxic, aptamers may emerge as strong candidates to reduce protein-protein interaction and hence protein aggregation in protein misfolding disorders in general.