Two photon imaging probe with highly efficient autofluorescence collection at high scattering and deep imaging conditions.

In this paper, we present a 2-photon imaging probe system featuring a novel fluorescence collection method with improved and reliable efficiency. The system aims to miniaturize the potential of 2-photon imaging in the metabolic and morphological characterization of cervical tissue at sub-micron resolution over large imaging depths into a flexible and clinically viable platform towards the early detection of cancers. Clinical implementation of such a probe system is challenging due to inherently low levels of autofluorescence, particularly when imaging deep in highly scattering tissues.

Autonomous circadian rhythms in the human hepatocyte regulate hepatic drug metabolism and inflammatory responses.

Critical aspects of physiology and cell function exhibit self-sustained ~24-hour variations termed circadian rhythms. In the liver, circadian rhythms play fundamental roles in maintaining organ homeostasis. Here, we established and characterized an in vitro liver experimental system in which primary human hepatocytes display self-sustained oscillations.

Ultrafast Laser Microlaryngeal Surgery for In Vivo Subepithelial Void Creation in Canine Vocal Folds.

Background/objectives: Tightly-focused ultrafast laser pulses (pulse widths of 100 fs-10 ps) provide high peak intensities to produce a spatially confined tissue ablation effect. The creation of sub-epithelial voids within scarred vocal folds (VFs) via ultrafast laser ablation may help to localize injectable biomaterials to treat VF scarring. Here, we demonstrate the feasibility of this technique in an animal model using a custom-designed endolaryngeal laser surgery probe.

Ultrafast laser surgery probe for sub-surface ablation to enable biomaterial injection in vocal folds.

Creation of sub-epithelial voids within scarred vocal folds via ultrafast laser ablation may help in localization of injectable therapeutic biomaterials towards an improved treatment for vocal fold scarring. Several ultrafast laser surgery probes have been developed for precise ablation of surface tissues; however, these probes lack the tight beam focusing required for sub-surface ablation in highly scattering tissues such as vocal folds. Here, we present a miniaturized ultrafast laser surgery probe designed to perform sub-epithelial ablation in vocal folds.

In vivo hamster cheek pouch subepithelial ablation, biomaterial injection, and localization: pilot study.

Significance: The creation of subepithelial voids within scarred vocal folds via ultrafast laser ablation may help in localization of injectable biomaterials toward a clinically viable therapy for vocal fold scarring.

Aim: We aim to prove that subepithelial voids can be created in a live animal model and that the ablation process does not engender additional scar formation. We demonstrate localization and long-term retention of an injectable biomaterial within subepithelial voids.

Sibling differences and parents' differential treatment of siblings: A multilevel meta-analysis.

The current study used meta-analysis to ask whether age differences, sex differences, and family size are linked to differences in parental treatment, as well as whether effect-sizes were moderated by the way parental differential treatment (PDT) was measured, who reported on the PDT, and the domain of PDT. Between August 2015 and November 2020, PsycINFO, Google Scholar, and PubMed Central were searched for articles relating to parental differential treatment; additionally, 13 sibling relationship scholars were contacted to collect unpublished analyses or unused data. Multilevel data came from 13,628 unique participants across 1,388 effect sizes nested within 66 sources (articles/raw data sets), nested within 23 unique samples (74% from North America; 26% from Western Europe).

The family stress model and parents' differential treatment of siblings: A multilevel meta-analysis.

The family stress model (FSM) suggests that stress, particularly economic stress, hinders effective parenting. Expanding on the FSM, the present study examined not only the economic stress but also the general stress and several contexts that may promote stress-namely, physical health, mental health, socioeconomic status, employment status, and marital status. The present study also expanded the FSM to examine parenting of sibling groups.

Mouse characteristics that affect establishing xenografts from hepatocellular carcinoma patient biopsies in the United States.

Background: Hepatocellular carcinoma (HCC) patient-derived xenograft (PDX) models hold potential to advance knowledge in HCC biology to help improve systemic therapies. Beside hepatitis B virus-associated tumors, HCC is poorly established in PDX.

Methods: PDX formation from fresh HCC biopsies were obtained and implanted intrahepatically or in subrenal capsule (SRC).

Ultrafast laser surgery probe with a calcium fluoride miniaturized objective for bone ablation.

We present a miniaturized ultrafast laser surgery probe with improved miniaturized optics to deliver higher peak powers and enable higher surgical speeds than previously possible. A custom-built miniaturized CaF objective showed no evidence of the strong multiphoton absorption observed in our previous ZnS-based probe, enabling higher laser power delivery to the tissue surface for ablation. A Kagome fiber delivered ultrashort pulses from a high repetition rate fiber laser to the objective, producing a focal beam radius of 1.

Thermal lensing effects and nonlinear refractive indices of fluoride crystals induced by high-power ultrafast lasers.

Thermo-optical and nonlinear property characterization of refractive optical components is essential for endoscopic instrumentation that utilizes high-power, high-repetition-rate ultrafast lasers. For example, ytterbium-doped fiber lasers are well suited for ultrafast laser microsurgery applications; however, the thermo-optical responses of many common lens substrates are not well understood at 1035 nm wavelength. Using a -scan technique, we first measured the nonlinear refractive indices of , , and at 1035 nm and found values that match well with those from the literature at 1064 nm.

Expansion, in vivo-ex vivo cycling, and genetic manipulation of primary human hepatocytes.

Primary human hepatocytes (PHHs) are an essential tool for modeling drug metabolism and liver disease. However, variable plating efficiencies, short lifespan in culture, and resistance to genetic manipulation have limited their use. Here, we show that the pyrrolizidine alkaloid retrorsine improves PHH repopulation of chimeric mice on average 10-fold and rescues the ability of even poorly plateable donor hepatocytes to provide cells for subsequent ex vivo cultures.

Scattering properties and femtosecond laser ablation thresholds of human and canine vocal folds at 776-nm wavelength.

Ultrafast laser ablation may provide a treatment for vocal fold (VF) scarring. Optical properties of VFs must be known prior to clinical implementation to select appropriate laser surgery conditions. We present scattering lengths of epithelium ℓs  ,  ep, superficial lamina propria ℓs  ,  SLP, and ablation thresholds Fth of human and canine VF tissues.

Pan-Genotype Hepatitis E Virus Replication in Stem Cell-Derived Hepatocellular Systems.

Background & Aims: The 4 genotypes of hepatitis E virus (HEV) that infect humans (genotypes 1-4) vary in geographical distribution, transmission, and pathogenesis. Little is known about the properties of HEV or its hosts that contribute to these variations. Primary isolates grow poorly in cell culture; most studies have relied on variants adapted to cancer cell lines, which likely alter virus biology.

Intrinsic Immunity Shapes Viral Resistance of Stem Cells.

Stem cells are highly resistant to viral infection compared to their differentiated progeny; however, the mechanism is mysterious. Here, we analyzed gene expression in mammalian stem cells and cells at various stages of differentiation. We find that, conserved across species, stem cells express a subset of genes previously classified as interferon (IFN) stimulated genes (ISGs) but that expression is intrinsic, as stem cells are refractory to interferon.

Humanized mice efficiently engrafted with fetal hepatoblasts and syngeneic immune cells develop human monocytes and NK cells.

Background & Aims: Human liver chimeric mice are useful models of human hepatitis virus infection, including hepatitis B and C virus infections. Independently, immunodeficient mice reconstituted with CD34(+) hematopoietic stem cells (HSC) derived from fetal liver reliably develop human T and B lymphocytes. Combining these systems has long been hampered by inefficient liver reconstitution of human fetal hepatoblasts.

Characterization of Lactate Sensors Based on Lactate Oxidase and Palladium Benzoporphyrin Immobilized in Hydrogels.

An optical biosensor for lactate detection is described. By encapsulating enzyme-phosphor sensing molecules within permeable hydrogel materials, lactate-sensitive emission lifetimes were achieved. The relative amount of monomer was varied to compare three homo- and co-polymer materials: poly(2-hydroxyethyl methacrylate) (pHEMA) and two copolymers of pHEMA and poly(acrylamide) (pAam).

Identification, molecular cloning, and analysis of full-length hepatitis C virus transmitted/founder genotypes 1, 3, and 4.

Unlabelled: Hepatitis C virus (HCV) infection is characterized by persistent replication of a complex mixture of viruses termed a "quasispecies." Transmission is generally associated with a stringent population bottleneck characterized by infection by limited numbers of "transmitted/founder" (T/F) viruses. Characterization of T/F genomes of human immunodeficiency virus type 1 (HIV-1) has been integral to studies of transmission, immunopathogenesis, and vaccine development.

Characterization of nonprimate hepacivirus and construction of a functional molecular clone.

Nonprimate hepacivirus (NPHV) is the closest known relative of hepatitis C virus (HCV) and its study could enrich our understanding of HCV evolution, immunity, and pathogenesis. High seropositivity is found in horses worldwide with ∼ 3% viremic. NPHV natural history and molecular virology remain largely unexplored, however.

Ultrastructural analysis of hepatitis C virus particles.

Hepatitis C virus (HCV) is a major cause of chronic liver disease, with an estimated 170 million people infected worldwide. Low yields, poor stability, and inefficient binding to conventional EM grids have posed significant challenges to the purification and structural analysis of HCV. In this report, we generated an infectious HCV genome with an affinity tag fused to the E2 envelope glycoprotein.

Modeling hepatitis C virus infection using human induced pluripotent stem cells.

Human pathogens impact patient health through a complex interplay with the host, but models to study the role of host genetics in this process are limited. Human induced pluripotent stem cells (iPSCs) offer the ability to produce host-specific differentiated cells and thus have the potential to transform the study of infectious disease; however, no iPSC models of infectious disease have been described. Here we report that hepatocyte-like cells derived from iPSCs support the entire life cycle of hepatitis C virus, including inflammatory responses to infection, enabling studies of how host genetics impact viral pathogenesis.

Expression of paramyxovirus V proteins promotes replication and spread of hepatitis C virus in cultures of primary human fetal liver cells.

Unlabelled: Here we demonstrate that primary cultures of human fetal liver cells (HFLC) reliably support infection with laboratory strains of hepatitis C virus (HCV), although levels of virus replication vary significantly between different donor cell preparations and frequently decline in a manner suggestive of active viral clearance. To investigate possible contributions of the interferon (IFN) system to control HCV infection in HFLC, we exploited the well-characterized ability of paramyxovirus (PMV) V proteins to counteract both IFN induction and antiviral signaling. The V proteins of measles virus (MV) and parainfluenza virus 5 (PIV5) were introduced into HFLC using lentiviral vectors encoding a fluorescent reporter for visualization of HCV-infected cells.

Endotracheal tube size does not affect time to extubation in adult cardiac surgery.

Managed care over the last 20 years has brought considerable attention to the impact of clinical variables on time to extubation in adult cardiac surgery. One variable that has not yet been analyzed is the endotracheal tube (ETT) size. Our retrospective electronic database review was performed on adult subjects that had a primary, non-emergent cardiac surgery in the last four years.

Hepatitis C virus induces interferon-λ and interferon-stimulated genes in primary liver cultures.

Unlabelled: Hepatitis C virus (HCV) replication in primary liver cells is less robust than that in hepatoma cell lines, suggesting that innate antiviral mechanisms in primary cells may limit HCV replication or spread. Here we analyzed the expression of 47 genes associated with interferon (IFN) induction and signaling following HCV infection of primary human fetal liver cell (HFLC) cultures from 18 different donors. We report that cell culture-produced HCV (HCVcc) induced expression of Type III (λ) IFNs and of IFN-stimulated genes (ISGs).

A novel nonoperative orthotopic colorectal cancer murine model using electrocoagulation.

Background: Orthotopic mouse models of human colorectal cancer represent an important in vivo tool for testing chemotherapeutic agents and studying intraluminal factors that may alter the growth of cancers. Currently the orthotopic mouse models of colorectal cancer require either an operative procedure or creation of colitis to implant the cancer cells in rectum. We have developed a nonoperative, minimally invasive technique to create a true orthotopic colon cancer mouse model.

Topical gentamicin does not provide any additional anastomotic strength when combined with fibrin glue.

Background: We evaluated the effect of a combination of fibrin sealant and topical gentamicin on a colonic anastomosis in a rat model.

Methods: Partial anastomosis in the transverse colon was performed in 70 male Sprague-Dawley rats aged 6 to 10 weeks using 5 interrupted sutures. The rats were divided into 4 groups (control, gentamicin, fibrin glue, and combination).