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1.
Oncologist ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864681

RESUMO

BACKGROUND: Individuals with cancer and other medical conditions often experience financial concerns from high costs-of-care and may utilize copay assistance programs (CAP). We sought to describe CAP recipients' experiences/preferences for cost discussions with clinicians. METHODS: We conducted a national, cross-sectional electronic-survey from 10/2022 to 11/2022 of CAP recipients with cancer or autoimmune conditions to assess patient perspectives on cost discussions. We used multivariable logistic regression models to explore associations of patient perspectives on cost discussions with patient characteristics and patient-reported outcomes (eg, financial toxicity, depression/anxiety, and health literacy). RESULTS: Among 1,566 participants, 71% had cancer and 29% had autoimmune conditions. Although 62% of respondents desired cost discussions, only 32% reported discussions took place. Additionally, 52% of respondents wanted their doctor to consider out-of-pocket costs when deciding the best treatment, and 61% of respondents felt doctors should ensure patients can afford treatment prescribed. Participants with depression symptoms were more likely to want doctors to consider out-of-pocket costs (OR = 1.54, P = .005) and to believe doctors should ensure patients can afford treatment (OR = 1.60, P = .005). Those with severe financial toxicity were more likely to desire cost discussions (OR = 1.65, P < .001) and want doctors to consider out-of-pocket costs (OR = 1.52, P = .001). Participants with marginal/inadequate health literacy were more likely to desire cost discussions (OR = 1.37, P = .01) and believe doctors should ensure patients can afford treatment (OR = 1.30, P = .036). CONCLUSIONS: In this large sample of CAP recipients with cancer and autoimmune conditions, most reported a desire for cost discussions, but under one-third reported such discussions took place.

2.
Oncologist ; 29(7): e918-e921, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38739017

RESUMO

Prescription drug costs within oncology remain a challenge for many patients with cancer. The Mark Cuban Cost Plus Drug Company (MCCPDC) launched in 2022, aiming to provide transparently priced medications at reduced costs. In this study, we sought to describe the potential impact of MCCPDC on Medicare Part-D oncology spending related to cancer-directed (n = 7) and supportive care (n = 26) drugs. We extracted data for drug-specific Part-D claims and spending for 2021. Using 90-count purchases from MCCPDC, we found potential Part-D savings of $857.8 million (91% savings) across the 7 cancer-directed drugs and $28.7 million (67% savings) across 21/26 (5/26 did not demonstrate savings) supportive care drugs. Collectively, our findings support that alternative purchasing models like MCCPDC may promote substantial health care savings.


Assuntos
Custos de Medicamentos , Neoplasias , Humanos , Estados Unidos , Neoplasias/tratamento farmacológico , Neoplasias/economia , Antineoplásicos/economia , Antineoplásicos/uso terapêutico , Redução de Custos , Cuba , Medicare/economia , Medicare Part D/economia
3.
Mol Ther Methods Clin Dev ; 32(1): 101216, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38440160

RESUMO

Adeno-associated virus (AAV) vectors are used for correcting multiple genetic disorders. Although the goal is to achieve lifelong correction with a single vector administration, the ability to redose would enable the extension of therapy in cases in which initial gene transfer is insufficient to achieve a lasting cure, episomal vector forms are lost in growing organs of pediatric patients, or transgene expression is diminished over time. However, AAV typically induces potent and long-lasting neutralizing antibodies (NAbs) against capsid that prevents re-administration. To prevent NAb formation in hepatic AAV8 gene transfer, we developed a transient B cell-targeting protocol using a combination of monoclonal Ab therapy against CD20 (for B cell depletion) and BAFF (to slow B cell repopulation). Initiation of immunosuppression before (rather than at the time of) vector administration and prolonged anti-BAFF treatment prevented immune responses against the transgene product and abrogated prolonged IgM formation. As a result, vector re-administration after immune reconstitution was highly effective. Interestingly, re-administration before the immune system had fully recovered achieved further elevated levels of transgene expression. Finally, this immunosuppression protocol reduced Ig-mediated AAV uptake by immune cell types with implications to reduce the risk of immunotoxicities in human gene therapy with AAV.

4.
Epidemics ; 46: 100754, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38428358

RESUMO

Hand, foot and mouth disease (HFMD) is highly prevalent in the Asia Pacific region, particularly in Vietnam. To develop effective interventions and efficient vaccination programs, we inferred the age-time-specific transmission patterns of HFMD serotypes enterovirus A71 (EV-A71), coxsackievirus A6 (CV-A6), coxsackievirus A10 (CV-A10), coxsackievirus A16 (CV-A16) in Ho Chi Minh City, Vietnam from a case data collected during 2013-2018 and a serological survey data collected in 2015 and 2017. We proposed a catalytic model framework with good adaptability to incorporate maternal immunity using various mathematical functions. Our results indicate the high-level transmission of CV-A6 and CV-A10 which is not obvious in the case data, due to the variation of disease severity across serotypes. Our results provide statistical evidence supporting the strong association between severe illness and CV-A6 and EV-A71 infections. The HFMD dynamic pattern presents a cyclical pattern with large outbreaks followed by a decline in subsequent years. Additionally, we identify the age group with highest risk of infection as 1-2 years and emphasise the risk of future outbreaks as over 50% of children aged 6-7 years were estimated to be susceptible to CV-A16 and EV-A71. Our study highlights the importance of multivalent vaccines and active surveillance for different serotypes, supports early vaccination prior to 1 year old, and points out the potential utility for vaccinating children older than 5 years old in Vietnam.


Assuntos
Benzenoacetamidas , Enterovirus , Febre Aftosa , Doença de Mão, Pé e Boca , Piperidonas , Criança , Lactente , Animais , Humanos , Pré-Escolar , Doença de Mão, Pé e Boca/epidemiologia , Vietnã/epidemiologia , Sorogrupo , China/epidemiologia
5.
Mol Ther Methods Clin Dev ; 32(1): 101206, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38390555

RESUMO

Self-complementary AAV vectors (scAAV) use a mutant inverted terminal repeat (mITR) for efficient packaging of complementary stranded DNA, enabling rapid transgene expression. However, inefficient resolution at the mITR leads to the packaging of monomeric or subgenomic AAV genomes. These noncanonical particles reduce transgene expression and may affect the safety of gene transfer. To address these issues, we have developed a novel class of scAAV vectors called covalently closed-end double-stranded AAV (cceAAV) that eliminate the mITR resolution step during production. Instead of using a mutant ITR, we used a 56-bp recognition sequence of protelomerase (TelN) to covalently join the top and bottom strands, allowing the vector to be generated with just a single ITR. To produce cceAAV vectors, the vector plasmid is initially digested with TelN, purified, and then subjected to a standard triple-plasmid transfection protocol followed by traditional AAV vector purification procedures. Such cceAAV vectors demonstrate yields comparable to scAAV vectors. Notably, we observed enhanced transgene expression as compared to traditional scAAV vectors. The treatment of mice with hemophilia B with cceAAV-FIX resulted in significantly enhanced long-term FIX expression. The cceAAV vectors hold several advantages over scAAV vectors, potentially leading to the development of improved human gene therapy drugs.

7.
Mol Ther ; 32(2): 325-339, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38053332

RESUMO

Upon viral infection of the liver, CD8+ T cell responses may be triggered despite the immune suppressive properties that manifest in this organ. We sought to identify pathways that activate responses to a neoantigen expressed in hepatocytes, using adeno-associated viral (AAV) gene transfer. It was previously established that cooperation between plasmacytoid dendritic cells (pDCs), which sense AAV genomes by Toll-like receptor 9 (TLR9), and conventional DCs promotes cross-priming of capsid-specific CD8+ T cells. Surprisingly, we find local initiation of a CD8+ T cell response against antigen expressed in ∼20% of murine hepatocytes, independent of TLR9 or type I interferons and instead relying on IL-1 receptor 1-MyD88 signaling. Both IL-1α and IL-1ß contribute to this response, which can be blunted by IL-1 blockade. Upon AAV administration, IL-1-producing pDCs infiltrate the liver and co-cluster with XCR1+ DCs, CD8+ T cells, and Kupffer cells. Analogous events were observed following coagulation factor VIII gene transfer in hemophilia A mice. Therefore, pDCs have alternative means of promoting anti-viral T cell responses and participate in intrahepatic immune cell networks similar to those that form in lymphoid organs. Combined TLR9 and IL-1 blockade may broadly prevent CD8+ T responses against AAV capsid and transgene product.


Assuntos
Linfócitos T CD8-Positivos , Fator 88 de Diferenciação Mieloide , Animais , Camundongos , Proteínas do Capsídeo , Células Dendríticas , Interleucina-1/metabolismo , Fígado/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-38130431

RESUMO

Recombinant adeno-associated viruses (AAVs) have emerged as a widely used gene delivery platform for both basic research and human gene therapy. To ensure and improve the safety profile of AAV vectors, substantial efforts have been dedicated to the vector production process development using suspension HEK293 cells. Here, we studied and compared two downstream purification methods, iodixanol gradient ultracentrifugation versus immuno-affinity chromatography (POROS™ CaptureSelect™ AAVX column). We tested multiple vector batches that were separately produced (including AAV5, AAV8, and AAV9 serotypes). To account for batch-to-batch variability, each batch was halved for subsequent purification by either iodixanol gradient centrifugation or affinity chromatography. In parallel, purified vectors were characterized, and transduction was compared both in vitro and in vivo in mice (using multiple transgenes: Gaussia luciferase, eGFP, and human factor IX). Each purification method was found to have its own advantages and disadvantages regarding purity, viral genome (vg) recovery, and relative empty particle content. Differences in transduction efficiency were found to reflect batch-to-batch variability rather than disparities between the two purification methods, which were similarly capable of yielding potent AAV vectors.

9.
Pediatr Infect Dis J ; 42(10): e366-e368, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37729666

RESUMO

A cross-sectional study was conducted on 205 pediatric patients, including 150 post-COVID-19 patients and 55 noninfected patients. The study identified 10 common respiratory symptoms in post-COVID-19 patients, with significant differences in clinical symptoms between the 2 groups. Post-COVID-19 pediatric patients had a lower lymphocyte count and a higher rate of pneumonia diagnosis, which can persist for up to 16 weeks after discharge. The study's findings can help monitor and manage the clinical burden of post-COVID-19 symptoms in the pediatric population.


Assuntos
COVID-19 , Criança Hospitalizada , Humanos , Criança , Síndrome de COVID-19 Pós-Aguda , Vietnã/epidemiologia , Estudos Transversais , COVID-19/epidemiologia
10.
bioRxiv ; 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37398133

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs that play a crucial role in modulating gene expression and are enriched in cell-derived extracellular vesicles (EVs). We investigated whether miRNAs from human islets and islet-derived EVs could provide insight into ß cell stress pathways activated during type 1 diabetes (T1D) evolution, therefore serving as potential disease biomarkers. We treated human islets from 10 cadaveric donors with IL-1ß and IFN-γ to model T1D ex vivo. MicroRNAs were isolated from islets and islet-derived EVs, and small RNA sequencing was performed. We found 20 and 14 differentially expressed (DE) miRNAs in cytokine- versus control-treated islets and EVs, respectively. Interestingly, the miRNAs found in EVs were mostly different from those found in islets. Only two miRNAs, miR-155-5p and miR-146a-5p, were upregulated in both islets and EVs, suggesting selective sorting of miRNAs into EVs. We used machine learning algorithms to rank DE EV-associated miRNAs, and developed custom label-free Localized Surface Plasmon Resonance-based biosensors to measure top ranked EVs in human plasma. Results from this analysis revealed that miR-155, miR-146, miR-30c, and miR-802 were upregulated and miR-124-3p was downregulated in plasma-derived EVs from children with recent-onset T1D. In addition, miR-146 and miR-30c were upregulated in plasma-derived EVs of autoantibody positive (AAb+) children compared to matched non-diabetic controls, while miR-124 was downregulated in both T1D and AAb+ groups. Furthermore, single-molecule fluorescence in situ hybridization confirmed increased expression of the most highly upregulated islet miRNA, miR-155, in pancreatic sections from organ donors with AAb+ and T1D.

11.
J Pediatr Pharmacol Ther ; 28(3): 212-221, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37303771

RESUMO

OBJECTIVE: To evaluate a pharmacist-led intervention's effectiveness in reducing drug-related problems (DRPs ( related to prescriptions for pediatric outpatients. METHODS: We conducted a randomized controlled trial. We recruited and randomly assigned 31 physicians to control or intervention groups. We collected 775 prescriptions (375 from the control group and 400 from the intervention group) at the start. For 3 weeks, intervention physicians received additional information and meetings with pharmacists in addition to the usual practices of the hospital. We then collected prescriptions at the end of the study. We classified DRPs, based on reliable references (Supplemental Table S1) at baseline and endpoint (a week after the intervention). The primary outcome was the proportion of prescriptions with DRPs, and secondary outcomes were the proportions of prescriptions with specific DRP types. RESULTS: The influence of the intervention on general DRPs and specific DRPs was the study's main finding. The pharmacist-led intervention helped reduce the prescriptions with DRPs proportion in the intervention group to 41.0%, compared with 49.3% in the control group (p < 0.05). The DRPs proportion related to the timing of administration relative to meals, unlike the other DRP types, increased in the control group (from 31.7% to 34.9%) and decreased in the intervention group (from 31.3% to 25.3%), with a significant difference between the 2 groups at endpoint (p < 0.01). Patients aged >2 to ≤6 years (OR, 1.871; 95% CI, 1.340-2.613) and receiving ≥5 drugs (OR, 5.037; 95% CI, 2.472-10.261) were at greater risk of experiencing DRPs related to prescribing. CONCLUSIONS: A pharmacist-led intervention improved DRP occurrence related to physicians' prescribing. Pharmacists could be involved in in-depth research with physicians in the prescribing process to provide tailored interventions.

12.
Biochim Biophys Acta Biomembr ; 1865(6): 184172, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37201561

RESUMO

Bacterial infections caused by Gram-negative pathogens, such as those in the family Enterobacteriaceae, are among the most difficult to treat because effective therapeutic options are either very limited or non-existent. This raises serious concern regarding the emergence and spread of multi-drug resistant (MDR) pathogens in the community setting; and thus, creates the need for discovery efforts and/or early-stage development of novel therapies for infections. Our work is directed towards branched polyethylenimine (BPEI) modified with polyethylene glycol (PEG) as a strategy for targeting virulence from Gram-negative bacterial pathogens. Here, we neutralize lipopolysaccharide (LPS) as a barrier to the influx of antibiotics. Data demonstrate that the ß-lactam antibiotic oxacillin, generally regarded as ineffective against Gram-negative bacteria, can be potentiated by 600 Da BPEI to kill some Escherichia coli and some Klebsiella pneumoniae. Modification of 600 Da BPEI with polyethylene glycol (PEG) could increase drug safety and improves potentiation activity. The ability to use the Gram-positive agent, oxacillin, against Gram-negative pathogens could expand the capability to deliver effective treatments that simplify, reduce, or eliminate some complicated treatment regimens.


Assuntos
Escherichia coli , Klebsiella pneumoniae , Polietilenoimina/farmacologia , Virulência , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Oxacilina/farmacologia , Bactérias Gram-Negativas
13.
Sci Rep ; 13(1): 8436, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231038

RESUMO

Although more adeno-associated virus AAV-based drugs enter the clinic, vector tissue tropism remains an unresolved challenge that limits its full potential despite that the tissue tropism of naturally occurring AAV serotypes can be altered by genetic engineering capsid vie DNA shuffling, or molecular evolution. To further expand the tropism and thus potential applications of AAV vectors, we utilized an alternative approach that employs chemical modifications to covalently link small molecules to reactive exposed Lysine residues of AAV capsids. We demonstrated that AAV9 capsid modified with N-ethyl Maleimide (NEM) increased its tropism more towards murine bone marrow (osteoblast lineage) while decreased transduction of liver tissue compared to the unmodified capsid. In the bone marrow, AAV9-NEM transduced Cd31, Cd34, and Cd90 expressing cells at a higher percentage than unmodified AAV9. Moreover, AAV9-NEM localized strongly in vivo to cells lining the calcified trabecular bone and transduced primary murine osteoblasts in culture, while WT AAV9 transduced undifferentiated bone marrow stromal cells as well as osteoblasts. Our approach could provide a promising platform for expanding clinical AAV development to treat bone pathologies such as cancer and osteoporosis. Thus, chemical engineering the AAV capsid holds great potential for development of future generations of AAV vectors.


Assuntos
Proteínas do Capsídeo , Capsídeo , Camundongos , Animais , Capsídeo/química , Proteínas do Capsídeo/química , Engenharia Genética , Tropismo , Maleimidas , Dependovirus/genética , Vetores Genéticos/genética , Transdução Genética
14.
Emerg Infect Dis ; 29(5): 1002-1006, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37015283

RESUMO

We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2/genética , Vietnã/epidemiologia , Surtos de Doenças
15.
Vaccine ; 41(13): 2208-2213, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36849339

RESUMO

BACKGROUND: Ongoing tetanus cases and sporadic outbreaks of vaccine-preventable diseases associated with routine vaccination programmes remain problems in many low and middle-income countries, including Vietnam. With no human-to-human transmission or natural immunity, tetanus antibody levels indicate both individual risk of tetanus and gaps in vaccination programmes. METHODS: To investigate gaps in immunity to tetanus in Vietnam, a country with a historically high level of tetanus vaccination coverage, tetanus antibodies were measure by ELISA from samples selected from a long-term serum bank, established for the purposes of general-population seroepidemiological investigations in southern Vietnam. Samples were selected from 10 provinces, focussing on age-groups targeted by national vaccination programmes for infants and pregnant women (Expanded Programme on Immunization, EPI, and Maternal and Neonatal Tetanus, MNT). RESULTS: Antibodies were measured from a total of 3864 samples. Highest tetanus antibody concentrations occurred in children under 4 years old, over 90 % of whom had protective levels. Approximately 70 % of children aged 7-12 years had protective antibody concentrations although there was variation among provinces. For infants and children, there were no significant differences in tetanus protection between males and females, but for adults aged 20-35 years, in five of the ten provinces surveyed, protection against tetanus was higher in females (p < 0.05) who are eligible for booster doses under the MNT programme. In seven of ten provinces, antibody concentrations were inversely related to age (p < 0.01) and protection of older individuals was generally low. CONCLUSION: Widespread immunity to tetanus toxoid is seen in infants and young children consistent with the high coverage rates reported for diptheria tetanus toxoid and pertussis (DTP) in Vietnam. However, the lower antibody concentrations seen in older children and men suggest reduced immunity to tetanus in populations not targeted by EPI and MNT programmes.


Assuntos
Tétano , Masculino , Lactente , Criança , Adulto , Recém-Nascido , Humanos , Feminino , Gravidez , Pré-Escolar , Tétano/prevenção & controle , Vietnã/epidemiologia , Toxoide Tetânico , Vacinação , Anticorpos Antibacterianos , Vacina contra Difteria, Tétano e Coqueluche
16.
Chem Biol Drug Des ; 101(3): 489-499, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34923750

RESUMO

Antibiotic resistance is a growing concern in the medical field. Drug-susceptible infections are often treated with ß-lactam antibiotics, which bind to enzymes known as penicillin-binding proteins (PBPs). When the PBPs are disabled, the integrity of the cell wall is compromised, leading to cell lysis. Resistance renders ß-lactam antibiotics ineffective, and clinicians turn to be more effective, but often more toxic, antibiotics. An alternative approach is combining antibiotics with compounds that disable resistance mechanisms. Previously, we have shown that low-molecular-weight 600 Da branched polyethylenimine restores ß-lactam susceptibility to Gram-positive and Gram-negative pathogens with antibiotic resistance. In this study, this approach is extended to the homodimers of 600 Da BPEI that have improved potentiation properties compared to monomers of 600 Da BPEI and 1200 Da BPEI. The homodimers are synthesized by linking two 600 Da BPEI molecules with methylenebisacrylamide (MBAA). The resulting product was characterized with FTIR spectroscopy, 1 H NMR spectroscopy, checkerboard microbroth dilution assays, and cell toxicity assays. These data show that the 600 Da BPEI homodimer is more effective than 1200 Da BPEI toward the potentiation of oxacillin against methicillin-resistant Staphylococcus epidermidis and the potentiation of piperacillin against Pseudomonas aeruginosa.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/química , Polietilenoimina/química , Polietilenoimina/farmacologia , Pseudomonas aeruginosa , Staphylococcus epidermidis , Dimerização , Monobactamas/farmacologia , beta-Lactamas/farmacologia , Testes de Sensibilidade Microbiana
17.
Am J Trop Med Hyg ; 108(1): 137-144, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36450229

RESUMO

We studied the development and persistence of neutralizing antibodies against SARS-CoV-2 ancestral strain, and Delta and Omicron (BA.1 and BA.2) variants in Vietnamese healthcare workers (HCWs) up to 15 weeks after booster vaccination. We included 47 HCWs, including group 1 (G1, N = 21) and group 2 (G2; N = 26) without and with breakthrough Delta variant infection before booster immunization, respectively). The study participants had completed primary immunization with ChAdOx1-S and booster vaccination with BNT162b2. Neutralizing antibodies were measured using a surrogate virus neutralization assay. Of the 21 study participants in G1, neutralizing antibodies against ancestral strain, Delta variant, BA.1, and BA.2 were (almost) abolished at month 8 after the second dose, but all had detectable neutralizing antibodies to the study viruses at week 2 post booster dose. Of the 26 study participants in G2, neutralizing antibody levels to BA.1 and BA.2 were significantly higher than those to the corresponding viruses measured at week 2 post breakthrough infection and before the booster dose. At week 15 post booster vaccination, neutralizing antibodies to BA.1 and BA.2 dropped significantly, with more profound changes observed in those without breakthrough Delta variant infection. Booster vaccination enhanced neutralizing activities against ancestral strain and Delta variant compared with those induced by primary vaccination. These responses were maintained at high levels for at least 15 weeks. Our findings emphasize the importance of the first booster dose in producing cross-neutralizing antibodies against Omicron variant. A second booster to maintain long-term vaccine effectiveness against the currently circulating variants merits further research.


Assuntos
Vacina BNT162 , COVID-19 , Humanos , Anticorpos Neutralizantes , Cinética , Imunização Secundária , População do Sudeste Asiático , COVID-19/prevenção & controle , SARS-CoV-2/genética , Vacinação , ChAdOx1 nCoV-19 , Infecções Irruptivas , Pessoal de Saúde , Anticorpos Antivirais
18.
J Med Virol ; 95(1): e28433, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36571262

RESUMO

Recombinant adeno-associated virus (rAAV) vectors carry a cassette of interest retaining only the inverted terminal repeats (ITRs) from the wild-type virus. Conventional rAAV production primarily uses a vector plasmid as well as helper genes essential for AAV replication and packaging. Nevertheless, plasmid backbone related contaminants have been a major source of vector heterogeneity. The mechanism driving the contamination phenomenon has yet to be elucidated. Here we identified cryptic resolution sites in the plasmid backbone as a key source for producing snapback genomes, which leads to the increase of vector genome heterogeneity in encapsidated virions. By using a single ITR plasmid as a model molecule and mapping subgenomic particles, we found that there exist a few typical DNA break hotspots in the vector DNA plasmid backbone, for example, on the ampicillin DNA element, called aberrant rescue sites. DNA around these specific breakage sites may assume some typical secondary structures. Similar to normal AAV vectors, plasmid DNA with a single ITR was able to rescue and replicate efficiently. These subgenomic DNA species significantly compete for trans factors required for rAAV rescue, replication, and packaging. The replication of single ITR contaminants during AAV production is independent of size. Packaging of these species is greatly affected by its size. A single ITR and a cryptic resolution site in the plasmid work synergistically, likely causing a source of plasmid backbone contamination.


Assuntos
DNA Viral , Vetores Genéticos , Humanos , Vetores Genéticos/genética , Plasmídeos/genética , DNA Viral/genética , Dependovirus/genética
19.
Opt Express ; 31(26): 43560-43573, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178449

RESUMO

A method for determining the phase shift of a Mach Zehnder interferometer (MZI) is presented. It is based on switching the wavelength of continuous wave (CW) laser light illuminating the MZI and measuring the interferometer output amplitudes at DC and switching frequency. The method can measure the MZI phase shift unambiguously over the entire phase shift range of 2π. A practical proof of concept demonstration shows that the method can perform real-time measurement with high repeatability and accuracy limited by the optical frequency drift and power fluctuation of the lasers. The method does not require modifications of the sensor or accessing to the laser electronics and also uses simple detection. It is, therefore, suitable for bio and medical sensing applications.

20.
Healthcare (Basel) ; 12(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38200936

RESUMO

BACKGROUND: Gastrointestinal malignancies represent a particularly challenging condition, often requiring a multidisciplinary approach to management in order to meet the unique needs of these individuals and their caregivers. PURPOSE: In this literature review, we sought to describe care delivery interventions that strive to improve the quality of life and care for patients with a focus on gastrointestinal malignancies. CONCLUSION: We highlight patient-centered care delivery interventions, including patient-reported outcomes, hospital-at-home interventions, and other models of care for individuals with cancer. By demonstrating the relevance and utility of these different care models for patients with gastrointestinal malignancies, we hope to highlight the importance of developing and testing new interventions to address the unique needs of this population.

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