Publications by authors named "Shannon A Allen"

Article Synopsis
  • Many young women globally experience the dual challenges of HIV and unintended pregnancies, highlighting the need for multipurpose prevention technologies.
  • A study involving 312 healthy women aged 18-34 randomized participants to use either a tenofovir/levonorgestrel (TFV/LNG), TFV-only, or placebo intravaginal ring to assess safety and effectiveness.
  • Results showed that both TFV IVR groups demonstrated significant increases in HIV inhibition in cervicovaginal fluid, with no serious adverse effects linked to the products, indicating their potential as safe prevention methods.
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Multipurpose prevention technology intravaginal rings (MPT IVRs) may offer a promising solution for addressing women's multiple sexual and reproductive health needs. We describe MPT IVR acceptability perspectives and examine user experiences of 25 cisgender women aged 18-34 years enrolled in a phase IIa randomized, partially blinded, placebo-controlled evaluation of tenofovir-based IVRs with and without contraceptive co-formulation. All took part in an individual, audio-recorded, semi-structured qualitative interview.

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In a phase-IIa trial, we investigated the influence of 90 days continuous-delivery tenofovir (TFV) intravaginal rings (IVRs) with/without levonorgestrel (LNG) on the genital microbiota of Kenyan women. Eligible women (n = 27; 18-34 years; negative for HIV, sexually transmitted infections, and Amsel-bacterial vaginosis) were randomized 2:2:1 to use of IVRs containing TFV, TFV/LNG, or placebo. Using vaginal wall and IVR swabs at IVR insertion and removal, the genital microbial composition was determined using 16S rRNA gene sequencing.

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Objective: We sought to investigate the effects of HIV infection on the vaginal microbiota and associations with treatment and demographic factors. We thus compared vaginal microbiome samples from HIV-infected (HIV+) and HIV-uninfected (HIV-) women collected at two Chicago area hospitals.

Design: We studied vaginal microbiome samples from 178 women analyzed longitudinally (n = 324 samples) and collected extensive data on clinical status and demographic factors.

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Currently, there are mounting data suggesting that HIV-1 acquisition in women can be affected by the use of certain hormonal contraceptives. However, in non-human primate models, endogenous or exogenous progestin-dominant states are shown to increase acquisition. To gain mechanistic insights into this increased acquisition, we studied how mucosal barrier function and CD4+ T-cell and CD68+ macrophage density and localization changed in the presence of natural progestins or after injection with high-dose DMPA.

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Unlabelled: The majority of human immunodeficiency virus type 1 (HIV-1) transmission events occur in women when semen harboring infectious virus is deposited onto the mucosal barriers of the vaginal, ectocervical, and endocervical epithelia. Seminal factors such as semen-derived enhancer of virus infection (SEVI) fibrils were previously shown to greatly enhance the infectivity of HIV-1 in cell culture systems. However, when SEVI is intravaginally applied to living animals, there is no effect on vaginal transmission.

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Although recovery after spinal cord injury (SCI) is rare in humans, recent literature indicates that some patients do recover sensorimotor function years after the trauma. This study seeks to elucidate the genetic underpinnings of SCI repair through the investigation of neurodegenerative and regenerative associated genes involved in the response to SCI during the chronic phase in adult rats. Intervention on the level of gene regulation focused on enhancing naturally attempting SCI regenerative genes has the potential to promote SCI repair.

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