Publications by authors named "Silvera R"

Peripheral nerve injury (PNI) is characterized by a loss of cellular and axonal integrity, often leading to limited functional recovery and pain. Many PNIs are not amenable to repair with traditional techniques; however, cell therapies, particularly Schwann cells (SCs), offer the promise of neural tissue replacement and functional improvement. Exosomes, which carry cellular signaling molecules, can be secreted by SCs and have shown promise in PNI.

View Article and Find Full Text PDF

Schwann cells are essential for the maintenance and function of motor neurons, axonal networks, and the neuromuscular junction. In amyotrophic lateral sclerosis, where motor neuron function is progressively lost, Schwann cell function may also be impaired. Recently, important signaling and potential trophic activities of Schwann cell-derived exosomal vesicles have been reported.

View Article and Find Full Text PDF

Background: People living with HIV (PLWH) have substantially increased incidence of anal precancer and cancer. There are very little data regarding genomic disturbances in anal precancers among PLWH. In this study, specific chromosomal variants were identified in anal squamous intraepithelial lesions.

View Article and Find Full Text PDF

Background: Cell-based therapy has emerged as a promising avenue for post-stroke recovery. A significant challenge lies in tracking the distribution and engraftment of transplanted cells within the target cerebral tissue. To address this, we turn to the potential of Brain MRI detection of mesenchymal stem cells (MSCs), achieved by labeling these cells with superparamagnetic iron oxide (SPIO).

View Article and Find Full Text PDF

There is a growing body of evidence that the delivery of cell-derived exosomes normally involved in intracellular communication can reduce secondary injury mechanisms after brain and spinal cord injury and improve outcomes. Exosomes are nanometer-sized vesicles that are released by Schwann cells and may have neuroprotective effects by reducing post-traumatic inflammatory processes as well as promoting tissue healing and functional recovery. The purpose of this study was to evaluate the beneficial effects of human Schwann-cell exosomes (hSC-Exos) in a severe model of penetrating ballistic-like brain injury (PBBI) in rats and investigate effects on multiple outcomes.

View Article and Find Full Text PDF

Background: The 2022 global mpox outbreak was notable for transmission between persons outside of travel and zoonotic exposures and primarily through intimate contact. An understanding of the presentation of mpox in people with human immunodeficiency virus (HIV) and other immunocompromising conditions and knowledge of the efficacy of tecovirimat continue to evolve.

Methods: This retrospective study describes clinical features and outcomes of persons with mpox who received tecovirimat.

View Article and Find Full Text PDF

Objective: To systematically evaluate the literature on the therapeutic use of Schwann cells (SC) in the repair of peripheral nerve injuries.

Methods: The Cochrane Library and PubMed databases were searched using terms [("peripheral nerve injury" AND "Schwann cell" AND "regeneration") OR ("peripheral nerve injuries")]. Studies published from 2008 to 2022 were eligible for inclusion in the present study.

View Article and Find Full Text PDF

Peripheral nerve injury (PNI) is found in a relatively large portion of trauma patients. If the injury is severe, such as with the presence of a long segmental gap, PNI can present a challenge for treatment. The current clinical standard of nerve harvest for the repair of long segmental gap PNI can lead to many potential complications.

View Article and Find Full Text PDF

Collective sex venues such as sex clubs are strategic sites to promote sexual health among sexual and gender minority individuals. We present qualitative findings from a multiple-method study on the acceptability of sexual-health services at collective sex venues in New York City (NYC) among attendees who identified as men, transgender, or gender non-conforming. In a survey used for sample selection ( = 342), most respondents (82.

View Article and Find Full Text PDF

Background: Healthcare-associated infections pose a potentially fatal threat to patients worldwide and Staphylococcus aureus is one of the most common causes of healthcare-associated infections. S. aureus is a common commensal pathogen and a frequent cause of bacteremia, with studies demonstrating that nasal and blood isolates from single patients match more than 80% of the time.

View Article and Find Full Text PDF

Objective: Schwann cells (SCs) have been shown to play an essential role in axon regeneration in both peripheral nerve injuries (PNIs) and spinal cord injuries (SCIs). The transplantation of SCs as an adjunctive therapy is currently under investigation in human clinical trials due to their regenerative capacity. Therefore, a reliable method for procuring large quantities of SCs from peripheral nerves is necessary.

View Article and Find Full Text PDF

The U.S. Food and Drug Administration (FDA) provides guidance for expanded access to experimental therapies, which in turn plays an important role in the Twenty-first Century Cures Act mandate to advance cell-based therapy.

View Article and Find Full Text PDF

Background: Anal cancer disproportionately affects people with HIV (PWH). High-grade squamous intraepithelial lesions (HSIL) are cancer precursors and treating them might prevent anal cancer. Data on adherence to HSIL treatment and surveillance is limited but needed to identify deficiencies of screening strategies.

View Article and Find Full Text PDF

Background: Screening strategies for high-risk human papillomavirus (hrHPV)-associated anal cancer are evolving. Herein, we compare anal cytology to hrHPV DNA testing and 2 novel cytology/hrHPV cotesting algorithms among 3 high-risk populations.

Methods: Anal cytology, hrHPV DNA testing, and high-resolution anoscopy (HRA)-guided biopsy results were analyzed from 1837 participants (1504 HIV-infected men who have sex with men (MSM), 155 HIV-uninfected MSM, and 178 HIV-infected women).

View Article and Find Full Text PDF

Nerve-derived human Schwann cell (SC) cultures are irreplaceable models for basic and translational research but their use can be limited due to the risk of fibroblast overgrowth. Fibroblasts are an ill-defined population consisting of highly proliferative cells that, contrary to human SCs, do not undergo senescence in culture. We initiated this study by performing an exhaustive immunological and functional characterization of adult nerve-derived human SCs and fibroblasts to reveal their properties and optimize a protocol of magnetic-activated cell sorting (MACS) to separate them effectively both as viable and biologically competent cells.

View Article and Find Full Text PDF

We report a water-soluble and non-toxic method to incorporate additional extracellular matrix proteins into gelatin hydrogels, while obviating the use of chemical crosslinkers such as glutaraldehyde. Gelatin hydrogels were fabricated using a range of gelatin concentrations (4%-10%) that corresponded to elastic moduli of approximately 1 kPa-25 kPa, respectively, a substrate stiffness relevant for multiple cell types. Microbial transglutaminase was then used to enzymatically crosslink a layer of laminin on top of gelatin hydrogels, resulting in 2-component gelatin-laminin hydrogels.

View Article and Find Full Text PDF

Overdose education and naloxone distribution (OEND) to people at risk of witnessing or experiencing an opioid overdose has traditionally been provided through harm reduction agencies. Expanding OEND to inpatient general medical settings may reach at-risk individuals who do not access harm reduction services and have not been trained. An OEND program targeting inpatients was developed, piloted, and evaluated on 2 general medicine floors at Montefiore Medical Center, a large urban academic medical center in Bronx, New York.

View Article and Find Full Text PDF

The effectiveness of HIV pre-exposure prophylaxis (PrEP) depends on adherence, which requires retention in PrEP care. We sought to examine factors associated with six-month retention in PrEP care among individuals prescribed PrEP between 2011 and 2015 in a large, academic health system in the Bronx, New York. We used multivariable logistic regression to identify factors independently associated with six-month retention.

View Article and Find Full Text PDF

Background: Perianal high-grade dysplasia (Bowen disease) is traditionally treated with mapping and wide excision with possible grafting rather than local ablation.

Objective: The aim of this study is to examine the results of high-grade perianal dysplasia ablation.

Data Sources: Data for this study were derived from a retrospective chart review at a surgical practice screening and treating patients for high-grade dysplasia between July 1998 and June 2013.

View Article and Find Full Text PDF

Background: Men who have sex with men have increased prevalence of both human papillomavirus and anogenital condyloma.

Objective: Risk factors for multiple treatment and recurrence of anal condyloma were examined.

Design: This is a retrospective study of HIV-negative men who have sex with men who were treated for anal condyloma.

View Article and Find Full Text PDF

Objective: Random biopsy (RB) of normal appearing cervix during colposcopy increases high-grade dysplasia (HSIL) diagnosis but has not been studied in high-resolution anoscopy (HRA), that is, colposcopy transferred to the anal canal. We investigated the utility of RB during HRA.

Design: At HRA, the anal canal was divided into 4 quadrants.

View Article and Find Full Text PDF

Macrophages are key players in the inflammatory response. In this study, we tested the hypothesis that although all macrophage subpopulations in tumor hosts are affected by the disease, it is the close proximity to the tumor that induces major alterations in these cells. We compared tumor-associated macrophages (TAMs) with peritoneal macrophages from mice bearing D1-DMBA-3 mammary tumors (T-PEMs).

View Article and Find Full Text PDF

Objectives: To understand the factors associated with knowledge of non-occupational post-exposure prophylaxis (nPEP) and pre-exposure prophylaxis (PrEP), bathhouse patrons in New York City (NYC) were surveyed.

Methods: 554 men who have sex with men (MSM) at two NYC bathhouses were given a standardised survey focused on nPEP and PrEP at the time of HIV testing.

Results: In the previous 90 days, 63% of respondents reported unprotected sex with a male partner and 7% reported any sex with a known HIV-positive male partner.

View Article and Find Full Text PDF

We have previously shown that peritoneal macrophages from mice bearing advanced D1-DMBA3 mammary tumors are impaired in their inflammatory functions but are not alternatively activated either and are less differentiated than the ones from normal mice. However, little is known about whether similar defects exist in their precursor stages as blood monocytes. We examined if blood monocytes from mammary tumor-bearing mice are already altered in their activation profiles before becoming macrophages and whether they correspond to inflammatory or resident monocyte subtypes.

View Article and Find Full Text PDF