Publications by authors named "Benjamin Richter"

Purpose: The significance of pancreatitis-associated hemorrhage outside the context of a ruptured pseudoaneurysm remains unclear. This study aims to characterize the clinical significance of pancreatic hemorrhage during acute pancreatitis (AP).

Methods: This retrospective study included adult patients diagnosed with hemorrhagic pancreatitis (HP) from 2010 to 2021.

View Article and Find Full Text PDF

Objective: To describe trends in the use of non-invasive tests (NIST) and the interval between a positive NIST and diagnostic colonoscopy.

Methods: Using a retrospective time-trend design, we examined medical records of patients within two large Indiana integrated healthcare systems who had a positive NIST between January 2019 and June 2021 and quantified the proportion of patients who had not completed colonoscopy within 60, 90, and 180 days to determine the interval between NIST result and diagnostic colonoscopy in days.

Results: Of 1379 patients with positive NISTs, 930 (68 %) underwent diagnostic colonoscopy during the 30-month study timeframe.

View Article and Find Full Text PDF

Severe rectal bleeding is a rare complication of chronic radiation proctitis (CRP). Given CRP's propensity to involve the full thickness of the rectal tissue, we proposed that endoscopic full-thickness resection may be a successful therapeutic modality for treating CRP. A 76-year-old man with multiple comorbid conditions who was not a surgical candidate presented with severe bleeding secondary to CRP that was refractory to all medical and therapeutic interventions.

View Article and Find Full Text PDF
Article Synopsis
  • Gallbladder cancer (GBC) is a serious disease typically diagnosed late, and while its incidence is rising in the US, specific trends based on race/ethnicity and stage at diagnosis are not well understood.
  • A study analyzed GBC incidence and mortality rates from 2001 to 2020 using data from the large American cancer databases, focusing on various racial/ethnic groups and different stages of the disease.
  • Findings showed a general decrease in GBC incidence across most races/ethnicities, with the exception of Non-Hispanic Blacks (NHB), who had an increasing trend until 2014; early-stage GBC incidence was only declining in Hispanics, while Non-Hispanic Whites (NH
View Article and Find Full Text PDF
Article Synopsis
  • Treating infections while managing coinfection poses significant challenges, especially as antibiotics can heighten the risk of additional infections or recurrences.
  • Current guidelines for managing these coinfections are lacking, leading to complex clinical decisions, particularly in acute situations like peptic ulcers or bleeding.
  • A case study illustrates effective management through a quadruple therapy approach, including vancomycin prophylaxis and bezlotoxumab, resulting in successful resolution of the patient's gastrointestinal issues.
View Article and Find Full Text PDF

Background: Colorectal cancer remains the second leading cause of cancer-related death in the US. As early-onset colorectal cancer (EO-CRC) becomes more prevalent in the US, research attention has shifted towards identifying at-risk populations. Previous studies have highlighted the rising rate of early-onset adenocarcinoma (ADC) and neuroendocrine tumors (NET) in the US.

View Article and Find Full Text PDF

Microneedles and, subsequently, microneedle arrays are emerging miniaturized medical devices for painless transdermal drug delivery. New and improved additive manufacturing methods enable novel microneedle designs to be realized for preclinical and clinical trial assessments. However, current literature reviews suggest that industrial manufacturers and researchers have focused their efforts on one-size-fits-all designs for transdermal drug delivery, regardless of patient demographic and injection site.

View Article and Find Full Text PDF

Two-photon polymerization (TPP) has been widely used to create 3D micro- and nanoscale scaffolds for biological and mechanobiological studies, which often require the mechanical characterization of the TPP fabricated structures. To satisfy physiological requirements, most of the mechanical characterizations need to be conducted in liquid. However, previous characterizations of TPP fabricated structures were all conducted in air due to the limitation of conventional micro- and nanoscale mechanical testing methods.

View Article and Find Full Text PDF

Cancer immunotherapy critically depends on fitness of cytotoxic and helper T cell responses. Dysfunctional cytotoxic T cell states in the tumor microenvironment (TME) are a major cause of resistance to immunotherapy. Intratumoral myeloid cells, particularly blood-borne myeloids (bbm), are key drivers of T cell dysfunction in the TME.

View Article and Find Full Text PDF

Oral vaccination of wildlife has shown to be a very effective management tool in rabies control. Evaluation of the genetic stability of vaccine viruses before distributing vaccine baits in the environment is essential because all available oral rabies vaccines, including the genetically engineered rabies virus vaccine strain SPBN GASGAS (Rabitec), are based on replication-competent viruses. To evaluate the genetic stability of this vaccine strain, five serial passages of the Master Seed Virus (MSV) in the production cell line BHK21 Cl13 were performed.

View Article and Find Full Text PDF

High-throughput sequencing (HTS) allows detection of known and unknown viruses in samples of broad origin. This makes HTS a perfect technology to determine whether or not the biological products, such as vaccines are free from the adventitious agents, which could support or replace extensive testing using various in vitro and in vivo assays. Due to bioinformatics complexities, there is a need for standardized and reliable methods to manage HTS generated data in this field.

View Article and Find Full Text PDF

Mechanotransduction via yes-associated protein (YAP) is a central mechanism for decision-making in mouse embryonic stem cells (mESCs). Nuclear localization of YAP is tightly connected to pluripotency and increases the cell division rate (CDR). How the geometry of the extracellular environment influences mechanotransduction, thereby YAP localization, and decision-making of single isolated mESCs is largely unknown.

View Article and Find Full Text PDF

Many essential cellular processes are regulated by mechanical properties of their microenvironment. Here, we introduce stimuli-responsive composite scaffolds fabricated by three-dimensional (3D) laser lithography to simultaneously stretch large numbers of single cells in tailored 3D microenvironments. The key material is a stimuli-responsive photoresist containing cross-links formed by noncovalent, directional interactions between β-cyclodextrin (host) and adamantane (guest).

View Article and Find Full Text PDF

Cardiomyocytes derived from induced pluripotent stem cells (iPSC-CMs) represent the best cell source for cardiac regenerative purposes but retain an immature phenotype after differentiation with significant limitations compared to adult cardiomyocytes. Apart from an incomplete cardiomyocyte-specific structure and microarchitecture, cells show at the level of Ca signaling only slow Ca release and reuptake properties. Here, we investigated the effect of restructuring single iPSC-CMs in specially designed 3D-micro-scaffolds on cell morphology and Ca handling.

View Article and Find Full Text PDF

This paper addresses the question of how a sustainable urban development can be supported through simple measured quantities in the context of the specific provision of green space and open space. The specific provision of green space is analysed based on a combination of six indicators that describe, on the one hand, the access of inhabitants to green spaces and on the other hand, the settlement character as well as the strong anthropogenic imprint on the urban landscape. The indicators were calculated and combined in a 9-cell matrix for classifying the areas studied.

View Article and Find Full Text PDF

The shape of animal cells is an important regulator for many essential processes such as cell migration or division. It is strongly determined by the organization of the actin cytoskeleton, which is also the main regulator of cell forces. Quantitative analysis of cell shape helps to reveal the physical processes underlying cell shape and forces, but it is notoriously difficult to conduct it in three dimensions.

View Article and Find Full Text PDF

Recent developments in stimulated-emission depletion (STED) microscopy have led to a step change in the achievable resolution and allowed breaking the diffraction limit by large factors. The core principle is based on a reversible molecular switch, allowing for light-triggered activation and deactivation in combination with a laser focus that incorporates a point or line of zero intensity. In the past years, the concept has been transferred from microscopy to maskless laser lithography, namely direct laser writing (DLW), in order to overcome the diffraction limit for optical lithography.

View Article and Find Full Text PDF

3D printing is a powerful emerging technology for the tailored fabrication of advanced functional materials. This Review summarizes the state-of-the art with regard to 3D laser micro- and nanoprinting and explores the chemical challenges limiting its full exploitation: from the development of advanced functional materials for applications in cell biology and electronics to the chemical barriers that need to be overcome to enable fast writing velocities with resolution below the diffraction limit. We further explore chemical means to enable direct laser writing of multiple materials in one resist by highly wavelength selective (λ-orthogonal) photochemical processes.

View Article and Find Full Text PDF

Optical micro-resonators have broad applications. They are used, for example, to enhance light-matter interactions in optical sensors or as model systems for investigating fundamental physical mechanisms in cavity quantum electrodynamics. Coupling two or more micro-cavities is particularly interesting as it enlarges the design freedom and the field of application.

View Article and Find Full Text PDF

Inhibition of the IκB kinase complex (IKK) has been implicated in the therapy of several chronic inflammatory diseases including inflammatory bowel diseases. In this study, using mice with an inactivatable IKKα kinase (Ikkα), we show that loss of IKKα function markedly impairs epithelial regeneration in a model of acute colitis. Mechanistically, this is caused by compromised secretion of cytoprotective IL-18 from IKKα-mutant intestinal epithelial cells because of elevated caspase 12 activation during an enhanced unfolded protein response (UPR).

View Article and Find Full Text PDF

The combination of three different photoresists into a single direct laser written 3D microscaffold permits functionalization with two bioactive full-length proteins. The cell-instructive microscaffolds consist of a passivating framework equipped with light activatable constituents featuring distinct protein-binding properties. This allows directed cell attachment of epithelial or fibroblast cells in 3D.

View Article and Find Full Text PDF

Background: Dimethyl fumarate (DMF) was approved by the US Food and Drug Administration (FDA) for treatment of relapsing-remitting multiple sclerosis (RRMS) based on two phase III randomized clinical trials (RCTs). There were not enough non-White patients enrolled in these RCTs to allow for subgroup analysis based on race. Efficacy and tolerability of DMF therapy across various racial groups is unknown.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates haptotaxis, the process where cells migrate towards gradients of proteins attached to a substrate, highlighting the mechanics behind it that are not well understood.
  • Researchers created controlled fibronectin dot patterns to analyze how various factors like dot size and concentration affect fibroblast movement, finding that specific conditions led to optimal cell migration towards areas of higher fibronectin density.
  • The findings revealed that cell movement depends on intracellular forces and interactions among proteins like RhoA, Cdc42, and aPKCζ, which play crucial roles in recognizing and responding to adhesive gradients during haptotaxis.
View Article and Find Full Text PDF