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1.
Cancer Discov ; 14(2): 274-289, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-37982575

ABSTRACT

Fulvestrant is used to treat patients with hormone receptor-positive advanced breast cancer, but acquired resistance is poorly understood. PlasmaMATCH Cohort A (NCT03182634) investigated the activity of fulvestrant in patients with activating ESR1 mutations in circulating tumor DNA (ctDNA). Baseline ESR1 mutations Y537S are associated with poor outcomes and Y537C with good outcomes. Sequencing of baseline and EOT ctDNA samples (n = 69) revealed 3/69 (4%) patients acquired novel ESR1 F404 mutations (F404L, F404I, and F404V), in cis with activating mutations. In silico modeling revealed that ESR1 F404 contributes to fulvestrant binding to estrogen receptor-alpha (ERα) through a pi-stacking bond, with mutations disrupting this bond. In vitro analysis demonstrated that single F404L, E380Q, and D538G models were less sensitive to fulvestrant, whereas compound mutations D538G + F404L and E380Q + F404L were resistant. Several oral ERα degraders were active against compound mutant models. We have identified a resistance mechanism specific to fulvestrant that can be targeted by treatments in clinical development. SIGNIFICANCE: Novel F404 ESR1 mutations may be acquired to cause overt resistance to fulvestrant when combined with preexisting activating ESR1 mutations. Novel combinations of mutations in the ER ligand binding domain may cause drug-specific resistance, emphasizing the potential of similar drug-specific mutations to impact the efficacy of oral ER degraders in development. This article is featured in Selected Articles from This Issue, p. 201.


Subject(s)
Breast Neoplasms , Circulating Tumor DNA , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Fulvestrant/pharmacology , Fulvestrant/therapeutic use , Estrogen Receptor alpha/genetics , Estrogen Receptor alpha/metabolism , Circulating Tumor DNA/genetics , Mutation
2.
Int J Mol Sci ; 21(13)2020 Jun 30.
Article in English | MEDLINE | ID: mdl-32629816

ABSTRACT

The formation of 3D multicellular spheroids in the ascites fluid of ovarian cancer patients is an understudied component of the disease progression. Spheroids are less sensitive to chemotherapy, in part due to the protection afforded by their structure, but also due to their slower proliferation rate. Previous studies suggest that the cell adhesion molecule Nectin-4 plays a key role in the formation of ovarian cancer spheroids. In this study, we further examined the role of Nectin-4 at early time points in spheroid formation using real-time digital photography. Human NIH:OVCAR5 ovarian cancer cells formed aggregates within 8 h, which further contracted into compact spheroids over 24 h. In contrast, Nectin-4 knockdown cells did not form tightly compacted spheroids. Synthetic peptides derived from Nectin-4 were tested for their ability to alter spheroid formation in two ovarian cancer cell lines. Nectin-4 peptide 10 (N4-P10) had an immediate effect on disrupting ovarian cancer spheroid formation, which continued for over 24 h, while a scrambled version of the peptide had no effect. N4-P10 inhibited spheroid formation in a concentration-dependent manner and was not cytotoxic; suggesting that N4-P10 treatment could maintain the cancer cells as single cells which may be more sensitive to chemotherapy.


Subject(s)
Cell Adhesion Molecules/pharmacology , Peptides/pharmacology , Spheroids, Cellular/drug effects , Ascites , Ascitic Fluid , Carcinoma, Ovarian Epithelial/drug therapy , Carcinoma, Ovarian Epithelial/metabolism , Cell Adhesion/drug effects , Cell Adhesion/physiology , Cell Adhesion Molecules/metabolism , Cell Aggregation/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Female , Humans , Nectins/metabolism , Nectins/pharmacology , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/metabolism , Ovary/metabolism , Peptides/chemical synthesis , Signal Transduction/drug effects , Tumor Cells, Cultured/drug effects
3.
J Nutr Educ Behav ; 51(5): 528-538, 2019 05.
Article in English | MEDLINE | ID: mdl-31078192

ABSTRACT

OBJECTIVE: To explore California local health department leaders' experiences planning, implementing, and evaluating nutrition promotion and obesity prevention programs for low-income families. DESIGN: Qualitative, cross-sectional study using semi-structured in-depth interviews and panel interviews conducted in 2015-2016. SETTING: California local health departments (LHDs) funded by the California Department of Public Health to implement Supplemental Nutrition Assistance Program-Education (SNAP-Ed). PARTICIPANTS: The authors recruited SNAP-Ed leaders from all 58 California LHDs implementing SNAP-Ed. Leaders from 49 LHDs participated: 36 in hour-long, in-depth interviews and 13 in 1 of 3 90-minute group panel interviews. PHENOMENON OF INTEREST: Processes, facilitators, and barriers connected to delivering SNAP-Ed reported by leaders in planning, implementing, and evaluating local programs. ANALYSIS: Interviews were transcribed, coded, and analyzed using Dedoose software. RESULTS: Leaders grappled with introducing, implementing, and integrating policy, systems, and environmental change interventions (PSEs). Information used to make planning decisions varied widely across LHDs. Partnership with nontraditional organizations was described as a resource- intensive, nonlinear process with recognized potential for benefit. Rural programs reported specific and different experiences compared with their urban counterparts. CONCLUSIONS AND IMPLICATIONS: Implementing new, complex interventions to improve diet and activity environments and behaviors is both exciting and challenging for local leaders. They expressed a desire for additional resources and capacity building to facilitate success, particularly related to policy, systems, and environmental change programs. Attention to the specific needs of rural counties is needed.


Subject(s)
Attitude of Health Personnel , Food Assistance/organization & administration , Health Personnel/psychology , Leadership , Public Health Practice , California , Cross-Sectional Studies , Humans , Interinstitutional Relations , Interviews as Topic , Local Government , Nutritional Sciences , Obesity , Poverty , Program Evaluation , Public Health , Rural Population
4.
Gigascience ; 7(5)2018 05 01.
Article in English | MEDLINE | ID: mdl-29718202

ABSTRACT

Genomic information is essential for taxonomic, phylogenetic, and functional studies to comprehensively decipher the characteristics of microorganisms, to explore microbiomes through metagenomics, and to answer fundamental questions of nature and human life. However, large gaps remain in the available genomic sequencing information published for bacterial and archaeal species, and the gaps are even larger for fungal type strains. The Global Catalogue of Microorganisms (GCM) leads an internationally coordinated effort to sequence type strains and close gaps in the genomic maps of microorganisms. Hence, the GCM aims to promote research by deep-mining genomic data.


Subject(s)
Bacteria/genetics , Fungi/genetics , Genomics/methods , Prokaryotic Cells/metabolism , Sequence Analysis, DNA/methods , Reproducibility of Results
5.
Respir Med Case Rep ; 19: 128-131, 2016.
Article in English | MEDLINE | ID: mdl-27709064

ABSTRACT

Löffler syndrome, a fulminant eosinophilic pneumonitis associated with the larval migratory phase of human parasites, is rarely reported in the United States. A previously healthy 8-year-old male was hospitalized with tachypnea, cough, hypoxemia, and fever of one week's duration. History revealed exposure to pigs on his family's farm in southernmost Louisiana, where the patient was responsible for cleaning the farm's pigpens. His fingernails were soiled and extremely short, with the edge of the nail bed exposed secondary to onychophagia. Laboratory evaluation demonstrated peripheral eosinophilia (39%), pulmonary eosinophilia (86%), high total IgE, diffuse reticulonodular lung opacities, and mixed obstructive and restrictive pulmonary function pattern. Systemic corticosteroids were initiated for his acute respiratory insufficiency and produced rapid clinical improvement. Serum Ascaris-specific IgE was markedly elevated and he was treated with albendazole. An extensive evaluation for other infectious and allergic etiologies was negative. A site visit to the family farm and laboratory investigation was coordinated with the Louisiana Animal Disease Diagnostic Laboratory at LSU. Ascaris suum eggs were detected in fresh pig feces and in the soil immediately surrounding the pens. Ascariasis should be considered even in the absence of travel history, especially in swine raising areas that are endemic for Ascaris in pigs, such as the southeastern United States. Onychophagia is a highly probable mechanism of zoonotic fecal-oral transmission in this case, and such habits could lead to continual reinfection. Systemic corticosteroids were effective in treating the patient's acute respiratory compromise due to Löffler syndrome.

7.
Appl Biochem Biotechnol ; 167(6): 1811-7, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22476929

ABSTRACT

Dioscorea alata var. purpurae (Indian purple yam) is an important source of diosgenin, a triterpenoid that is used as a raw material in the synthesis of corticosteroid hormones. These drugs are used for the treatment of pharmacological conditions such as arthritis. This paper reports in vitro propagation of explants of various parts of Dioscorea-tuber, leaves, and nodes. Murashige and Skoog media supplemented with hormones and additives was used to get maximum callus initiation and shoot/root induction. All the cultures were maintained at 25 ± 2 °C under cool-white fluorescent tubes with 16-h photoperiod. Callus initiation was observed from 8th to 11th day of inoculation, and subsequent root/shoot was initiated in nodal callus after 21 days. Hormones such as kinetin, indole-3-acetic acid, indole-3-butyric acid, α-naphthalene acetic acid, and thiadizuron did not show significant enhancement. Also, there was no need for supplementing additives (silver nitrate, glutamine, L-: asparagine monohydrate, polyethylene glycol). Combination of 6-benzylaminopurine (0.2 ppm) and 2,4-dichlorophenoxyacetic acid (2 ppm) hormones gave the best results, and all parts of the plants gave similar callus induction.


Subject(s)
Dioscorea/growth & development , In Vitro Techniques , Plant Growth Regulators/physiology
8.
PLoS One ; 6(10): e25828, 2011.
Article in English | MEDLINE | ID: mdl-21998703

ABSTRACT

INTRODUCTION: Stable heterosexual HIV-1 serodiscordant couples in Africa have high HIV-1 transmission rates and are a critical population for evaluation of new HIV-1 prevention strategies. The Partners PrEP Study is a randomized, double-blind, placebo-controlled trial of tenofovir and emtricitabine-tenofovir pre-exposure prophylaxis to decrease HIV-1 acquisition within heterosexual HIV-1 serodiscordant couples. We describe the trial design and characteristics of the study cohort. METHODS: HIV-1 serodiscordant couples, in which the HIV-1 infected partner did not meet national guidelines for initiation of antiretroviral therapy, were enrolled at 9 research sites in Kenya and Uganda. The HIV-1 susceptible partner was randomized to daily oral tenofovir, emtricitabine-tenofovir, or matching placebo with monthly follow-up for 24-36 months. RESULTS: From July 2008 to November 2010, 7920 HIV-1 serodiscordant couples were screened and 4758 enrolled. For 62% (2966/4758) of enrolled couples, the HIV-1 susceptible partner was male. Median age was 33 years for HIV-1 susceptible and HIV-1 infected partners [IQR (28-40) and (26-39) respectively]. Most couples (98%) were married, with a median duration of partnership of 7.0 years (IQR 3.0-14.0) and recent knowledge of their serodiscordant status [median 0.4 years (IQR 0.1-2.0)]. During the month prior to enrollment, couples reported a median of 4 sex acts (IQR 2-8); 27% reported unprotected sex and 14% of male and 1% of female HIV-1 susceptible partners reported sex with outside partners. Among HIV-1 infected partners, the median plasma HIV-1 level was 3.94 log(10) copies/mL (IQR 3.31-4.53) and median CD4 count was 496 cells/µL (IQR 375-662); the majority (64%) had WHO stage 1 HIV-1 disease. CONCLUSIONS: Couples at high risk of HIV-1 transmission were rapidly recruited into the Partners PrEP Study, the largest efficacy trial of oral PrEP. (ClinicalTrials.gov NCT00557245).


Subject(s)
Anti-HIV Agents/pharmacology , HIV Infections/prevention & control , HIV Seronegativity/drug effects , HIV Seropositivity/transmission , HIV-1/drug effects , Adenine/analogs & derivatives , Adenine/pharmacology , Adolescent , Adult , Cohort Studies , Deoxycytidine/analogs & derivatives , Deoxycytidine/pharmacology , Emtricitabine , Female , Heterosexuality , Humans , Male , Middle Aged , Organophosphonates/pharmacology , Risk-Taking , Sexual Behavior/statistics & numerical data , Tenofovir , Young Adult
9.
Health Aff (Millwood) ; 30(8): 1488-97, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21821565

ABSTRACT

Couples in sub-Saharan Africa are the largest group in the world at risk for HIV infection. Couples counseling and testing programs have been shown to reduce HIV transmission, but such programs remain rare in Africa. Before couples counseling and testing can become the norm, it is essential to increase demand for the services. We evaluated the effectiveness of several promotional strategies during a two-year program in Kitwe and Ndola, Zambia. The program attracted more than 7,600 couples through the use of radio broadcasts, billboards, and other strategies. The most effective recruiting technique was the use of local residents trained as "influence agents" to reach out to friends, neighbors, and others in their sphere of influence.


Subject(s)
Counseling , Family Characteristics , HIV Infections/prevention & control , HIV Seropositivity/diagnosis , Persuasive Communication , Community Networks , Female , Humans , Male , Mass Screening , Program Evaluation , Zambia
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