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Nanoplastic (NP) pollution is receiving increasing attention regarding its potential effects on human health. The identification and quantification of intracellular NPs are prerequisites for an accurate risk assessment, but appropriate methods are lacking. Here we present a label-free technique to simultaneously visualize and quantify the bioaccumulation of NPs based on hyperspectral imaging with enhanced dark-field microscopy (HSI-DFM). Using polystyrene NPs (PS NPs) as representative particles, the construction of a hyperspectral library was optimized first with more accurate NP identification achieved when the library was based on intracellular instead of extracellular PS NPs. The PS NPs used herein were labeled with a green fluorescent dye so that the accuracy of HSI-DFM in identifying and quantifying intracellular NPs can be evaluated, by comparing the results with those obtained by fluorescence microscopy and flow cytometry. The validation of HSI-DFM for use in determinations of the NP concentration at the single-cell level allows analyses of the accumulation kinetics of NPs in single living cells. The utility of HSI-DFM in different cell lines and with NPs differing in their chemical composition was also demonstrated. HSI-DFM therefore provides a new approach to studies of the accumulation and distribution of NPs in human cells.

Understanding the mitotic DNA damage response (DDR) is critical to our comprehension of cancer, premature aging and developmental disorders which are marked by DNA repair deficiencies. In this study we use a micro-focused laser to induce DNA damage in selected mitotic chromosomes to study the subsequent repair response. Our findings demonstrate that (1) mitotic cells are capable of DNA repair as evidenced by DNA synthesis at damage sites, (2) Repair is attenuated when DNA-PKcs and ATM are simultaneously compromised, (3) Laser damage may permit the observation of previously undetected DDR proteins when damage is elicited by other methods in mitosis, and (4) Twenty five percent of mitotic DNA-damaged cells undergo a subsequent mitosis. Together these findings suggest that mitotic DDR is more complex than previously thought and may involve factors from multiple repair pathways that are better understood in interphase.

Understanding the mitotic DNA damage response (DDR) is critical to our comprehension of cancer, premature aging and developmental disorders which are marked by DNA repair deficiencies. In this study we use a micro-focused laser to induce DNA damage in selected mitotic chromosomes to study the subsequent repair response. Our findings demonstrate that (1) mitotic cells are capable of DNA repair as evidenced by DNA synthesis at damage sites, (2) Repair is attenuated when DNA-PKcs and ATM are simultaneously compromised, (3) Laser damage may permit the observation of previously undetected DDR proteins when damage is elicited by other methods in mitosis, and (4) Twenty five percent of mitotic DNA-damaged cells undergo a subsequent mitosis. Together these findings suggest that mitotic DDR is more complex than previously thought and may involve factors from multiple repair pathways that are better understood in interphase.

The human body require energy for mechanical activities. This energy is obtained from the food we eat and they are stored in the human body in chemical form as Carbohydrates, Protein and Fats. In the event that energy is needed in any part of the body, the chemical energy is transformed into utilizable energy form as Adenosine Triphosphate (ATP) and transported to places within the cells where they are needed. This is in some ways similar to the energy generation in the diesel engine of an automobile. In this paper, the mathematical equation governing the generation of energy in a diesel engine is modified to produce a mathematical model of energy generation in the mitochondria of human cell. A partial differential equation with boundary conditions, representing the process of energy generation in the human cell, was obtained. The solution to the integer partial derivative mathematical model was first obtained using Homotopy Analysis Method (HAM). Surface plots of the solution obtained by HAM are presented. From the study, the energy generated in the human cells increases with time as the coefficient of diffusion increases and also whenever the control parameter is in the negative side of the convergence region. Furthermore, a fractional-time partial derivative model was also formulated by replacing the integer-time derivative with a fractional derivative in the Caputo sense. The solution to the fractional-time derivative model was also obtained using the Homotopy Analysis Method (HAM) and surface plot of solution are also presented. In comparing the integer-derivative model with that of the fractional derivative model, the energy generated by the integer model seems higher than that of the fractional model. The fractional-time derivative model is a generalization of the integer derivative model. When α = 1, the solution of the integer and fractional model coincide. The novelty and contribution of this paper is the formulation of a mathematical model of energy generation in the mitochondria of human cell through the food we eat. Both integer derivative and fractional derivative models were formulated. Approximate analytic solutions to both models were obtained using the Homotopy Analysis Method. [ABSTRACT FROM AUTHOR]

With the growing prevalence of plastic use, the environmental release of plastic waste is escalating, and fragmented nanoscale plastic particles are emerging as significant environmental threats. This study aimed to evaluate the cytotoxic effects of fragmented polyethylene nanoplastics (PE NPs) manufactured using a focused ultrasonic system. The ultrasonic irradiation process generated fragmented PE NPs with a geometric mean diameter of 85.14 ± 5.37 nm and a size range of 25-350 nm. To assess cytotoxicity, we conducted a series of tests on various human cell lines, including stomach, blood, colon, lung, skin, liver, and brain-derived cells. The testing involved MTS-based cell viability assays to evaluate direct impacts on cell viability, lactate dehydrogenase (LDH) leakage assays to measure membrane damage, and ELISA to quantify TNF-α release as an indicator of inflammation. Although PE-NPs did not immediately induce apoptosis, significant LDH leakage and elevated TNF-α levels were observed across all cell lines, indicating membrane damage and inflammatory responses. Additionally, flow cytometry and TEM analyses revealed the intracellular accumulation of PE-NPs, further supporting their cytotoxic potential. These results demonstrate that fragmented PE-NPs can disrupt cellular membranes and induce inflammatory responses through accumulation within cells. The findings suggest that these NPs pose potential hazards to cell viability and underscore the need for further research into their environmental and health impacts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

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Recent progress in the field of organoid-based cell culture systems has enabled the use of patient-derived cells in conditions that resemble those in cancer tissue, which are better than two-dimensional (2D) cultured cell lines. In particular, organoids allow human cancer cells to be handled in conditions that resemble those in cancer tissue, resulting in more efficient establishment of cells compared with 2D cultured cell lines, thus enabling the use of multiple patient-derived cells with cells from different genetic background, in keeping with the heterogeneity of the cells. One of the most valuable points of using organoids is that human cells from either healthy or cancerous tissue can be used. Using genome editing technology such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein, organoid genomes can be modified to, for example, cancer-prone genomes. The normal, cancer, or genome-modified organoids can be used to evaluate whether chemicals have genotoxic or non-genotoxic carcinogenic activity by evaluating the cancer incidence, cancer progression, and cancer metastasis. In this review, the organoid technology and the accompanying technologies were summarized and the advantages of organoid-based toxicology and its application to pancreatic cancer study were discussed. [ABSTRACT FROM AUTHOR]

Axonal injury and stress have long been thought to play a pathogenic role in a variety of neurodegenerative diseases. However, a model for studying single-cell axonal injury in mammalian cells and the processes of repair has not been established. The purpose of this study was to examine the response of neuronal growth cones to laser-induced axonal damage in cultures of embryonic rat hippocampal neurons and induced pluripotent stem cell (iPSC) derived human neurons. A 532-nm pulsed [Formula: see text] picosecond laser was focused to a diffraction limited spot at a precise location on an axon using a laser energy/power that did not rupture the cell membrane (subaxotomy). Subsequent time series images were taken to follow axonal recovery and growth cone dynamics. After laser subaxotomy, axons thinned at the damage site and initiated a dynamic cytoskeletal remodeling process to restore axonal thickness. The growth cone was observed to play a role in the repair process in both hippocampal and iPSC-derived neurons. Immunofluorescence staining confirmed structural tubulin damage and revealed initial phases of actin-based cytoskeletal remodeling at the damage site. The results of this study indicate that there is a repeatable and cross-species repair response of axons and growth cones after laser-induced damage.

Recent progress in the field of organoid-based cell culture systems has enabled the use of patient-derived cells in conditions that resemble those in cancer tissue, which are better than two-dimensional (2D) cultured cell lines. In particular, organoids allow human cancer cells to be handled in conditions that resemble those in cancer tissue, resulting in more efficient establishment of cells compared with 2D cultured cell lines, thus enabling the use of multiple patient-derived cells with cells from different genetic background, in keeping with the heterogeneity of the cells. One of the most valuable points of using organoids is that human cells from either healthy or cancerous tissue can be used. Using genome editing technology such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein, organoid genomes can be modified to, for example, cancer-prone genomes. The normal, cancer, or genome-modified organoids can be used to evaluate whether chemicals have genotoxic or non-genotoxic carcinogenic activity by evaluating the cancer incidence, cancer progression, and cancer metastasis. In this review, the organoid technology and the accompanying technologies were summarized and the advantages of organoid-based toxicology and its application to pancreatic cancer study were discussed.

It is essential to identify intermediate marker endpoints of carcinogenesis for the evaluation of the effectiveness of cancer-chemopreventive agents. We have observed that levels of proteolytic activities (as detected by 4 different substrates) are increased 2-3-fold (P < 0.003) in oral buccal mucosa cells of smokers and patients with oral leukoplakia or erythroplakia as compared to a nonsmoking comparison group. In addition, proteolytic activity levels in the buccal cells were increased nearly 3-fold in patients with oral trauma (P < 0.01) or diabetes (P < 0.02), as well as pregnant women (P < 0.04). Excluding these subgroups of patients in epidemiological studies increase the differences in levels of proteolytic activities between both the nonsmoking comparison group and smokers and between the comparison group and patients with oral leukoplakia or erythroplakia. Evaluation of prerandomization levels of proteolytic activities of patients in cancer chemoprevention trials will increase the statistical power by allowing stratified randomization based on levels of proteolytic activities. The observed increases in levels of proteolytic activities in tissues at higher than normal risk of cancer development suggest that levels of proteolytic activities should be used as immediate marker endpoints in human cancer prevention trials using protease inhibitors as potential anticarcinogenic agents.

The efficiency of replating of cells from primary colonies grown in semisolid medium has been used to detect and quantitate self-renewal in vitro. A positive correlation has been found by others between the replating efficiency of cells from myelogenous leukemia and patient survival. In the current study we measured primary and secondary replating efficiency of metastatic melanoma cells from subcutaneous tissues or lymph nodes of twelve patients and related these results to patient survival from time of biopsy. No relationship was found between primary and secondary plating efficiency nor for primary or secondary replating efficiency and survival. These results suggest that colony-forming melanoma cells grown under anchorage-independent conditions do not identify a stem cell population important for survival distinct from highly proliferative cells. These studies do not, however, rule out the possibility that a non-clonogenic transitional cell population exists in the tumor.

Endometriosis is characterized by the presence of endometrial glands and stroma in extrauterine sites. Our objective was to determine whether endometriotic lesions (ELs) from women with endometriosis have altered retinoid levels compared with their eutopic endometrium, and to test the hypothesis that defects in all-trans retinoic acid (ATRA) biosynthesis in EL is related to reduced expression of cellular retinol-binding protein type 1 (RBP1). Retinoids were evaluated by liquid chromatography-tandem mass spectrometry and high-performance liquid chromatography in eutopic endometrial biopsies (EBs) and ELs from 42 patients with pathologically confirmed endometriosis. The ATRA levels were reduced, whereas the retinol and retinyl ester concentrations were elevated in EL compared with EB tissue. Similar results were found in a mouse model of endometriosis that used green fluorescent protein-positive endometrial tissue injected into the peritoneum of syngeneic hosts to mimic retrograde menses. The ATRA biosynthesis in vitro in retinol-treated primary human endometrial stromal cell (ESC) cultures derived from ELs was reduced compared with that of ESCs derived from patient-matched EBs. Correspondingly, RBP1 expression was reduced in tissue and ESCs derived from EL versus EB. Rbp1(-/-) mice showed reduced endometrial ATRA concentrations compared with wild type, associated with loss of tissue organization and hypercellularity. These findings provide the first quantitative measurements of ATRA in human endometrium and endometriosis, demonstrating reduced ATRA in ectopic tissue and corresponding ESC cultures. Quantitation of retinoids in murine endometriosis and in Rbp1(-/-) mice supports the contention that impaired ATRA synthesis caused by reduced RBP1 promotes an "endometriosis phenotype" that enables cells to implant and grow at ectopic sites.

The incidence of melanoma is one of the fastest growing of all tumor types in the United States and the number of cases worldwide has doubled in the past 30 years. Melanoma, which arises from melanocytes, is an extremely aggressive tumor that invades the vascular and lymphatic systems to establish tumors elsewhere in the body. Melanoma is a particularly resilient cancer and systemic therapy approaches have achieved minimal success against metastatic melanoma resulting in only a few FDA-approved treatments with limited benefit. Leading treatments offer minimal efficacy with response rates generally under 15% in the long term with no clear effect on melanoma-related mortality. Even the recent success of the specific BRAF mutant inhibitor vemurafenib has been tempered somewhat since acquired resistance is rapidly observed. Thus, understanding the mechanism(s) of melanoma carcinogenesis is paramount to combating this deadly disease. Not only for the treatment of melanoma but, ultimately, for prevention. In this report, we will summarize our work to date regarding the characterization of ultraviolet radiation (UVR)-mediated melanomagenesis and highlight several promising avenues of ongoing research. © 2014 Elsevier B.V. All rights reserved.

Intrinsic disorder can be found in all proteomes of all kingdoms of life and in viruses, being particularly prevalent in the eukaryotes. We conduct a comprehensive analysis of the intrinsic disorder in the human proteins while mapping them into 24 compartments of the human cell. In agreement with previous studies, we show that human proteins are significantly enriched in disorder relative to a generic protein set that represents the protein universe. In fact, the fraction of proteins with long disordered regions and the average protein-level disorder content in the human proteome are about 3 times higher than in the protein universe. Furthermore, levels of intrinsic disorder in the majority of human subcellular compartments significantly exceed the average disorder content in the protein universe. Relative to the overall amount of disorder in the human proteome, proteins localized in the nucleus and cytoskeleton have significantly increased amounts of disorder, measured by both high disorder content and presence of multiple long intrinsically disordered regions. We empirically demonstrate that, on average, human proteins are assigned to 2.3 subcellular compartments, with proteins localized to few subcellular compartments being more disordered than the proteins that are localized to many compartments. Functionally, the disordered proteins localized in the most disorder-enriched subcellular compartments are primarily responsible for interactions with nucleic acids and protein partners. This is the first-time disorder is comprehensively mapped into the human cell. Our observations add a missing piece to the puzzle of functional disorder and its organization inside the cell. [ABSTRACT FROM AUTHOR]

Robust strategies for developing patient-specific, human, induced pluripotent stem cell (iPSC)-based therapies of the brain require an ability to derive large numbers of highly defined neural cells. Recent progress in iPSC culture techniques includes partial-to-complete elimination of feeder layers, use of defined media, and single-cell passaging. However, these techniques still require embryoid body formation or coculture for differentiation into neural stem cells (NSCs). In addition, none of the published methodologies has employed all of the advances in a single culture system. Here we describe a reliable method for long-term, single-cell passaging of PSCs using a feeder-free, defined culture system that produces confluent, adherent PSCs that can be differentiated into NSCs. To provide a basis for robust quality control, we have devised a system of cellular nomenclature that describes an accurate genotype and phenotype of the cells at specific stages in the process. We demonstrate that this protocol allows for the efficient, large-scale, cGMP-compliant production of transplantable NSCs from all lines tested. We also show that NSCs generated from iPSCs produced with the process described are capable of forming both glia defined by their expression of S100β and neurons that fire repetitive action potentials.

Retinol (ROL) and its biologically active metabolite, all-trans retinoic acid (ATRA), are essential for a number of reproductive processes. However, there is a paucity of information regarding their roles in ovarian folliculogenesis, oocyte maturation, and early embryogenesis. The objectives of this study were to quantify and compare peripheral plasma (PP) and follicular fluid (FF) retinoid levels, including ATRA in women undergoing in vitro fertilization (IVF) and to investigate the relationship between retinoid levels and embryo quality. Retinoid levels were evaluated in PP and FF from 79 women undergoing IVF at the time of oocyte retrieval and corresponding embryo quality assessed on a daily basis after retrieval for 3 days until uterine transfer. Analysis compared the retinoid levels with day 3 embryo grades and between endometriosis versus control patients. Results demonstrated distinctive levels of retinoid metabolites and isomers in FF versus PP. There was a significantly larger percentage of high-quality grade I embryos derived from the largest versus smallest follicles. An increase in follicle size also correlated with a >50% increase in FF ROL and ATRA concentrations. Independent of follicle size, FF yielding grade I versus nongrade I embryos showed higher mean levels of ATRA but not ROL. In a nested case-control analysis, control participants had 50% higher mean levels of ATRA in their FF and PP than women with endometriosis. These findings strongly support the proposition that ATRA plays a fundamental role in oocyte development and quality, and that reduced ATRA synthesis may contribute to decreased fecundity of participants with endometriosis.

Our previous studies have shown that nitric oxide (NO) plays an important role in increasing the invasion and proliferation of human melanoma cells, suggesting that targeting NO signaling may facilitate therapy and prevention. Neuronal nitric oxide synthase (nNOS) is present in melanocytes, a cell type that originates from the neural crest. The aims of this study were to determine the role of nNOS in melanoma progression and the potential antitumor effects of novel synthesized nNOS inhibitors.In vitro studies demonstrated abundant expression of nNOS in melanoma compared to melanocytes, which was inducible by ultraviolet radiation and was associated with increased NO generation. nNOS was also detected in melanoma biopsies that increased with disease stage. Knockdown of nNOS in melanoma cells diminished L-arginine-induced NO production; the metastatic capacity was also reduced as well as the levels of MMP-1, Bcl-2, JunD, and APE/Ref-1. Similar inhibition of NO and invasion potential was observed utilizing novel, highly selective nNOS inhibitors. In three-dimensional human skin reconstructs, the nNOS inhibitor cpd8 effectively reversed the melanoma overgrowth stimulated by NO stress.Our work lays the foundation for development of clinical "drug-like" nNOS inhibitors as a new and promising strategy for the chemoprevention of early melanoma progression and the inhibition of secondary melanoma in high-risk individuals.Based on our observations, we propose that nNOS in melanoma results in constitutive overproduction of NO, which stimulates proliferation and increases invasion potential, leading to subsequent development of metastases.

The UDP-glucuronosyltransferase (UGT) family of enzymes plays a vital role in the detoxification of carcinogens as well as clearance of anti-cancer drugs. In humans, 19 UGT family members have been identified and are expressed in a tissue specific manner throughout the body. However, the UGTs have not been previously characterized in melanocytes or melanoma. In the present study, UGT2B7, UGT2B10, and UGT2B15 were identified as being normally expressed in human melanocytes. The same three UGT family members were also expressed in the primary melanoma cell line WM115. No UGT expression was detected in another primary melanoma cell line, WM3211, or in any metastatic melanoma cell line examined. These results suggest that UGT expression is lost during melanoma progression. Treatment of WM3211 or metastatic melanoma cell lines with anti-cancer agents (including vemurafenib) induced expression of UGT2B7, UGT2B10 and UGT2B15 demonstrating that melanoma cells retain the ability to re-express these same three UGTs. The corresponding increase in glucuronidation activity in melanoma cells following anti-cancer treatment was also observed. Furthermore, knockdown of UGT2B7 in WM115 cells sensitized these cells to treatment by adriamycin and epirubicin indicating that UGT2B7 is involved in resistance to these drugs. However, knockdown of UGT2B7 had no effect on temozolomide toxicity. Taken together, these results clearly demonstrate a role for UGTs in melanoma etiology. Since the UGTs are drug metabolism enzymes, we propose that re-expression of the UGTs constitutes a previously unsuspected mechanism for intratumoral drug resistance in melanoma.

As a survival factor for melanocytes lineage cells, MiTF plays multiple roles in development and melanomagenesis. What role MiTF plays in the DNA damage response is currently unknown. In this report we observed that MiTF was phosphorylated at serine 73 after UVC radiation, which was followed by proteasome-mediated degradation. Unlike after c-Kit stimulation, inhibiting p90RSK-1 did not abolish the band shift of MiTF protein, nor did it abolish the UVC-mediated MiTF degradation, suggesting that phosphorylation on serine 73 by Erk1/2 is a key event after UVC. Furthermore, the MiTF-S73A mutant (Serine 73 changed to Alanine via site-directed mutagenesis) was unable to degrade and was continuously expressed after UVC exposure. Compared to A375 melanoma cells expressing wild-type MiTF (MiTF-WT), cells expressing MiTF-S73A mutant showed less p21 WAF1/CIP1 accumulation and a delayed p21 WAF1/CIP1 recovery after UVC. Consequently, cells expressing MiTF-WT showed a temporary G1 arrest after UVC, but cells expressing MiTF-S73A mutant or lack of MiTF expression did not. Finally, cell lines with high levels of MiTF expression showed higher resistance to UVC-induced cell death than those with low-level MiTF. These data suggest that MiTF mediates a survival signal linking Erk1/2 activation and p21 WAF1/CIP1 regulation via phosphorylation on serine 73, which facilitates cell cycle arrest. In addition, our data also showed that exposure to different wavelengths of UV light elicited different signal pathways involving MiTF.

The inside of living cells is highly crowded with biological macromolecules. It has long been considered that the properties of nucleic acids and proteins, such as their structures, dynamics, interactions, and enzymatic activities, in intracellular environments are different from those under in vitro dilute conditions. In-cell NMR is a robust and powerful method used in the direct measurement of those properties in living cells. However, until 2 years ago, in-cell NMR was limited to Xenopus laevis oocytes due to technical challenges of incorporating exogenous nucleic acids. In the last 2 years, in-cell NMR spectra of nucleic acid introduced into living human cells have been reported. By use of the in-cell NMR spectra of nucleic acids in living human cells, the formation of hairpin structures with Watson–Crick base pairs, and i-motif and G-quadruplex structures with non-Watson–Crick base pairs was demonstrated. Others investigated the mRNA–antisense drug interactions and DNA–small compound interactions. In this article, we review these studies to underscore the potential of in-cell NMR for addressing the structures, dynamics, and interactions of nucleic acids in living human cells. [ABSTRACT FROM AUTHOR]

It is well recognized that nitric oxide (NO) is involved in tumor progression, including melanoma. Measurement of proliferative and metastatic capacity by MTS and Matrigel invasion assays, respectively, was done and showed that NO-treated melanoma cells exhibited a higher capacity compared with control, especially metastatic Lu1205 cells. Apurinic/apyrimidinic endonuclease-1/redox factor-1 (APE/Ref-1) is a multifunctional protein and its role in tumor biology has attracted considerable attention. To determine whether APE/Ref-1 plays a role in mediating NO stimulation of melanoma progression, we investigated the effect of DETA/NO on levels of APE/Ref-1 and related downstream targets [activator protein-1 (AP-1)/JunD, matrix metalloproteinase-1 (MMP-1), Bcl-2, and inducible nitric oxide synthase (iNOS)] by Western blot and reverse transcription-PCR analysis. Following DETA/NO treatment, APE/Ref-1 and other downstream molecules were induced. Knockdown of APE/Ref-1 or AP-1/JunD by specific small interfering RNA markedly reversed the induction by NO stress of target proteins. These results present evidence for the existence of a functional feedback loop contributing to progression and metastasis of melanoma cells. Resveratrol has been shown to be an APE/Ref-1 inhibitor and significant decreases in AP-1/JunD, MMP-1, Bcl-2, and iNOS protein levels occurred after exposure to resveratrol. This phenolic antioxidant may be an appropriate choice for combining with other compounds that develop resistance by up-regulation of these molecules.

Although attempts to develop any viable chemotherapeutic approaches to combat metastatic cancers have largely failed, potential genetic targets to halt metastatic progression continue to be identified. As drugs are developed to address these targets, there is a need for high-throughput systems that accurately reproduce in vivo microenvironments to gauge their efficacy. Accordingly, we have developed a three-dimensional in vitro culture system representative of the environment present upon secondary metastasis to quantitatively measure tumor cell invasion in this setting three-dimensionally. Culturing melanomas of different metastatic capacities within the system showed that each cell type invades the matrix in a manner commensurate to its known metastatic potential in vivo. Moreover, the developed quantitative schemes were put to use to characterize the effect of microenvironmental influences (i.e., matrix components, interstitial cell presence) on planar and vertical melanoma invasion. We propose this novel, quantitative system as a useful tool to assess the effects of pharmacologic and/or microenvironmental influences on tumor cell invasion at a metastatic site.

BackgroundSerial interventions are often used to reduce the risk of health care-associated methicillin-resistant Staphylococcus aureus (MRSA) infections. To our knowledge, the relative impact of these interventions has not previously been ascertained.MethodsWe conducted a retrospective study of 4 major infection control interventions using an interrupted time series design to evaluate their impact on MRSA bacteremia in an 800-bed hospital with 8 intensive care units (ICUs). Interventions were introduced 1 at a time during a 9-year period and involved the promotion of compliance with maximal sterile barrier precautions during central venous catheter placement, the institution of alcohol-based hand rubs for hand disinfection, the introduction of a hand hygiene campaign, and the institution of routine nares surveillance cultures for MRSA in all ICUs for patients on ICU admission and weekly thereafter while in the ICU. Positive cultures resulted in the initiation of contact isolation precautions. Using segmented regression analyses, we evaluated changes in monthly incidence and prevalence of MRSA bacteremia from their predicted values. Methicillin-susceptible Staphylococcus aureus bacteremia was monitored as a control.ResultsRoutine surveillance cultures and subsequent contact isolation precautions resulted in substantial reductions in MRSA bacteremia in both ICUs and non-ICUs. In 16 months, the incidence density of MRSA bacteremia decreased by 75% in ICUs (P=.007) and by 40% in non-ICUs (P=.008), leading to a 67% hospital-wide reduction in the incidence density of MRSA bacteremia (P=.002). Methicillin-susceptible S. aureus bacteremia rates remained stable during this time. The other interventions were not associated with a statistically significant change in MRSA bacteremia.ConclusionsRoutine surveillance for MRSA in ICUs allowed earlier initiation of contact isolation precautions and was associated with large and statistically significant reductions in the incidence of MRSA bacteremia in the ICUs and hospital wide. In contrast, no similar decrease was attributable to the other infection control interventions.

They have proposed that ASICs are responsible for the differentiation of LUHMES (Lund Human Mesencephalic) cells, a line of human cells capable of differentiating into dopaminergic-like neurons (Zuberek et al., [26]; Harischandra et al., [5]). Keywords: acid-sensing ion channel; dopamine cell; differentiation; patch-clamp recording; human cell EN acid-sensing ion channel dopamine cell differentiation patch-clamp recording human cell 1 3 3 11/25/21 20211122 NES 211122 Introduction Acid-sensing ion channels (ASICs) are proton-gated Na SP + sp channels widely located in the peripheral and central nervous system (Waldmann et al., [21]; Krishtal, [9]). Differentiation, patch-clamp recording, acid-sensing ion channel, dopamine cell, human cell. [Extracted from the article]

Resveratrol has demonstrated preventive and therapeutic activities in a variety of tumors. However, the mechanistic basis of its pharmacological effects on human melanoma has not been well defined. Our results demonstrated that resveratrol significantly inhibited melanoma anchorage-independent growth, and even at high doses no distinct apoptosis or cell cycle arrest was observed. It is noteworthy that c83-2c (metastatic) and wm3211 (radial growth phase) melanoma cells became more dendritic shaped with resveratrol treatment. Major histocompatibility complex (MHC) class I antigen and Fas/CD95 constitutive surface expression levels were, respectively, increased by 2.7- and 1.6-fold of control in c83-2c cells. Resveratrol reduced both activator protein-1 (AP-1) DNA binding and transcriptional activities, and supershift assay revealed that AP-1 composition was shifted from c-Jun/JunD/Fra-1 to JunD/Fra-1/Fra-2, with markedly increased JunD, Fra-1, and Fra-2 protein expression levels in the nucleus. Furthermore, we overexpressed Fra-2 in human melanoma cells by using a Fra-2 expression construct and both AP-1 transcriptional activity and 12-O-tetradecanoylphorbol-induced transcriptional transactivation were reduced significantly, whereas MHC class I antigen and Fas/CD95 levels were elevated to 2.0 and 1.8 times of control, respectively. Addition of H(2)O(2) (10 muM) partially reversed the inhibition of colony proliferation; however, no effects on either MHC class I antigen or Fas expression was evident. Although H(2)O(2) restored participation of c-Jun in AP-1 complexes, H(2)O(2) addition did not affect the induction of Fra-1 and Fra-2 by resveratrol nor the morphological changes. We propose that alterations in AP-1 transcription signaling, mediated by changes in AP-1 dimeric composition and reduced intracellular reactive oxygen species levels, substantially contribute to the phenotypic changes induced by resveratrol.

The alcohol-abuse deterrent disulfiram (DSF) is shown to have a highly selective toxicity against melanoma in culture, inducing a largely apoptotic response, with much lower toxicity against several other cell lines. Melanoma cell lines derived from different stages (radial, vertical, and metastatic phase) were all sensitive to DSF treatment in vitro; melanocytes were only slightly affected. A required role of extracellular Cu is demonstrated for DSF toxicity. Low concentrations of DSF alone decreased the number of viable cells, and the addition of CuCl(2) significantly enhanced the DSF-induced cell death to less than 10% of control. Significantly, the intracellular Cu concentration of melanoma cells increased rapidly upon DSF treatment. Both the intracellular Cu uptake and the toxicity induced by DSF were blocked by co-incubation with bathocuproine disulfonic acid (BCPD, 100 muM), a non-membrane-permeable Cu chelator. Chemical studies demonstrated a complicated, extracellular redox reaction between Cu(II) and DSF, which forms the complex Cu(deDTC)(2) in high yield, accompanied by oxidative decomposition of small amounts of disulfiram. The Cu complex has somewhat higher activity against melanoma and is suggested to be the active agent in DSF-induced toxicity. The redox conversion of DSF was unique to Cu(II) and not engendered by the other common biological metal ions Fe(II or III), Mn(III), and Zn(II). The implications of this work are significant both in the possible treatment of melanoma as well as in limiting the known side-effects of DSF, which we propose may be diminished by cotreatment to decrease adventitious Cu.

Computer-assisted image analysis is useful for quantifying the histologic and molecular changes of sun-induced squamous cell carcinoma progression. We used the CAS 200 image analysis system to measure nuclear morphometric parameters, p53 expression, and proliferation markers in actinic keratosis (AK), sun-exposed, and normal skin in 51 patients. Nuclear morphometry revealed significant increases in nuclear absorbance, irregularity of nuclear shape, and nuclear size in AK compared with normal and sun-damaged skin. These parameters showed significantly greater variability in AK nuclei. Argyrophyllic nucleolar organizer area and number were also significantly greater in AK compared with sun-damaged skin and normal skin. Ki67 and p53 expressions were both increased in sun-damaged skin relative to normal and greater still in AK. These data are evidence that sun damage induces proliferation and p53 abnormalities before the appearance of nuclear abnormalities and their associated DNA instability. Following these changes during a skin cancer chemopreventative trial can then help assess the efficacy of the agent and help determine where in the progression of neoplastic changes it exerts its biological effects.

BackgroundAutism is a pervasive developmental disorder characterized by a triad of deficits: qualitative impairments in social interactions, communication deficits, and repetitive and stereotyped patterns of behavior. Although autism is etiologically heterogeneous, family and twin studies have established a definite genetic basis. The inheritance of idiopathic autism is presumed to be complex, with many genes involved; environmental factors are also possibly contributory. The analysis of chromosome abnormalities associated with autism contributes greatly to the identification of autism candidate genes.Case presentationWe describe a child with autistic disorder and an interstitial deletion on chromosome 4q. This child first presented at 12 months of age with developmental delay and minor dysmorphic features. At 4 years of age a diagnosis of Pervasive Developmental Disorder was made. At 11 years of age he met diagnostic criteria for autism. Cytogenetic studies revealed a chromosome 4q deletion. The karyotype was 46, XY del 4 (q31.3-q33). Here we report the clinical phenotype of the child and the molecular characterization of the deletion using molecular cytogenetic techniques and analysis of polymorphic markers. These studies revealed a 19 megabase deletion spanning 4q32 to 4q34. Analysis of existing polymorphic markers and new markers developed in this study revealed that the deletion arose on a paternally derived chromosome. To date 33 genes of known or inferred function are deleted as a consequence of the deletion. Among these are the AMPA 2 gene that encodes the glutamate receptor GluR2 sub-unit, GLRA3 and GLRB genes that encode glycine receptor subunits and neuropeptide Y receptor genes NPY1R and NPY5R.ConclusionsThe deletion in this autistic subject serves to highlight specific autism candidate genes. He is hemizygous for AMPA 2, GLRA3, GLRB, NPY1R and NPY5R. GluR2 is the major determinant of AMPA receptor structure. Glutamate receptors maintain structural and functional plasticity of synapses. Neuropeptide Y and its receptors NPY1R and NPY5R play a role in hippocampal learning and memory. Glycine receptors are expressed in very early cortical development. Molecular cytogenetic studies and DNA sequence analysis in other patients with autism will be necessary to confirm that these genes are involved in autism.

We demonstrated previously that c-Jun, JunB and c-Fos RNA were dysregulated in metastatic melanoma cells compared with normal human melanocytes. The purpose of this study was to evaluate the distribution in composition of AP-1 dimers in human melanoma pathogenesis. We investigated AP-1 dimer pairing in radial growth phase-like (RGP) (w3211) and vertical growth phase-like (VGP) (w1205) human melanoma cells and metastatic cell lines (cloned from patients, c83-2c, c81-46A, A375, respectively) compared with melanocytes using electrophoretic mobility shift assay (EMSA), Western blot and transfection analyses. There are progressive variations in AP-1 composition in different melanoma cell lines compared with normal melanocytes, in which c-Jun, JunD and FosB were involved in AP-1 complexes. In w3211, c-Jun, JunD and Fra-1 were involved in AP-1 binding, while in w1205, overall AP-1 binding activity was decreased significantly and supershift binding was detected only with JunD antibodies. In metastatic c81-46A and A375 cells, only JunD was involved in AP-1 binding activity, but in a third (c83-2c) c-Jun, JunD and Fra-1 were present. Western blot evaluation detected c-Jun in melanocytes and w3211, but this component was decreased significantly or was not detectable in w1205, c81-46A and A375 cells. In contrast, JunD protein was elevated in c81-46A and c83-2c cells compared with melanocytes and RGP and VGP cell lines. Normal melanocytes and c83-2c cells (which have c-Jun involved in AP-1 binding), transfected with c-Jun antisense and treated with cisplatin, showed higher viability compared with untransfected cells, while in c81-46A cells (in which only JunD is detectable) no change in cell viability was observed following treatment with cisplatin and c-jun antisense transfection. A dominant-negative c-Jun mutant (TAM67) significantly increased the soft agar colony formation of w3211 and c83-2c cells. These results suggest that components of AP-1, especially c-Jun, may offer a new target for the prevention or treatment of human melanoma progression.

In a sporadic case of autism and language deficit due to auditory processing defects, molecular genetic studies revealed that a chromosomal deletion occurred in the 13q12-->q13 region. No chromosome abnormalities were detected in the parents. We determined that the deletion occurred on the paternally derived chromosome 13. There are two previous reports of chromosome 13 abnormalities in patients with autism. The deletion in the subject described in this paper maps between the two chromosome 13 linkage peaks described by Bradford et al. (2001) in studies of subjects with autism and language deficits. The 9-Mb region deleted in the patient described here contains at least four genes that are expressed in brain and that play a role in brain development. They are NBEA, MAB21L1, DCAMKL1 and MADH9. These genes therefore represent candidate genes for autism and specific language deficits.

In a sporadic case of autism and language deficit due to auditory processing defects, molecular genetic studies revealed that a chromosomal deletion occurred in the 13q12-->q13 region. No chromosome abnormalities were detected in the parents. We determined that the deletion occurred on the paternally derived chromosome 13. There are two previous reports of chromosome 13 abnormalities in patients with autism. The deletion in the subject described in this paper maps between the two chromosome 13 linkage peaks described by Bradford et al. (2001) in studies of subjects with autism and language deficits. The 9-Mb region deleted in the patient described here contains at least four genes that are expressed in brain and that play a role in brain development. They are NBEA, MAB21L1, DCAMKL1 and MADH9. These genes therefore represent candidate genes for autism and specific language deficits.

The BCR/ABL oncogene results from a balanced translocation between chromosomes 9 and 22 and is found in patients with chronic myeloid leukemia (CML) and in some patients with acute B-lymphoid leukemia. The Bcr/Abl fusion protein is a constitutively active tyrosine kinase that stimulates several intracellular signaling pathways, including activation of Ras through direct binding of the SH2-containing adapter protein Grb2 to Bcr tyrosine 177. A tyrosine-to-phenylalanine mutation (Y177F) at this site blocks the co-association of Bcr/Abl and Grb2 in vivo and impairs focus formation by Bcr/Abl in fibroblasts. However, the Bcr/Abl Y177F mutant can transform hematopoietic cell lines and primary bone marrow cells in vitro, so the importance of the Bcr/Abl-Grb2 interaction to myeloid and lymphoid leukemogenesis in vivo is unclear. We have recently demonstrated the efficient induction of CML-like myeloproliferative disease by BCR/ABL in a murine bone marrow transduction/transplantation model system. The Y177F mutation greatly attenuates the myeloproliferative disease induced by BCR/ABL, with mice developing B- and T-lymphoid leukemias of longer latency. In addition, the v-abl oncogene of Abelson murine leukemia virus, whose protein product lacks interaction with Grb2, is completely defective for the induction of CML-like disease. These results suggest that direct binding of Grb2 is required for the efficient induction of CML-like myeloproliferative disease by oncogenic Abl proteins. (Blood. 2000;96:664-670)

The protease catalyzing the hydrolysis of the tripeptide fluorescence substrate, butoxycarbonyl-valine-proline-arginine-(7-amino-4-methylcoumarin) (Boc-Val-Pro-Arg-MCA) and the neu oncogenic protein are potentially useful biomarkers for human cancer prevention studies. In the present study, we standardized a specific substrate hydrolysis method for measuring this protease activity in human oral mucosal cells and characterized the relationship between neu oncogene expression and protease activity in patients enrolled in an oral cancer prevention trial using Bowman Birk Inhibitor Concentrate (BBIC) as the cancer preventive agent. The results demonstrate that changes in the protease activity in oral mucosal cells after BBIC treatment correlated with the changes in the neu protein levels in oral mucosal cells (r = 0.726, P < 0.001) and serum (r = 0.675, P < 0.001), suggesting that the Boc-Val-Pro-Arg-MCA hydrolyzing activity can be as useful as neu oncogene expression as a cancer biomarker. In the 25 patients enrolled in the study, the level of neu protein in oral mucosal cells correlated with the serum neu protein concentration in the patients before BBIC treatment (r = 0.645, P < 0.001). However, such a correlation was not observed after the BBIC treatment, suggesting that BBI may inhibit serine protease(s) involved in the cleavage of neu protein on the cell surface, thereby preventing the release of the extracellular domain of neu protein into the circulation. By inhibiting the cleavage of neu protein on the cell surface, BBI could prevent malignant and premalignant cells expressing high levels of neu protein antigen from escaping host immunological surveillance control.

The Fifth International workshop on chromosome 9 comprised a gathering of 36 scientists from seven countries and included a fairly even distribution of interests along chromosome 9 as well as a strong input from more global activities and from comparative mapping. At least eight groups had participated in the goal set at the previous workshop which was to improve the fine genetic mapping in different regions of chromosome 9 by meiotic breakpoint mapping in allocated regions and this has resulted in some greatly improved order information. Excellent computing facilities were available and all contributed maps were entered not only into SIGMA (and thence submitted to GDB) but also into a dedicated version of ACEDB which can be accessed on the Web in the form of one of 28 slices into which the chromosome has been arbitrarily divided. It was generally agreed that the amount of data is now overwhelming and that the integration and validation of all data is not only unrealistic in a short meeting but probably impossible until the whole chromosome has been sequenced and fully annotated. Sequence-ready contigs presented at the meeting totalled about 3 MB which is about one fiftieth of the estimated length. The single biggest barrier to integration of maps is the problem of non-standard nomenclature of loci. In the past 2 workshops efforts have been made to compare traditional 'consensus' maps made by human insight (still probably best for small specific regions) with those generated with some computer assistance (such as SIGMA) and those generated objectively by defined computer algorithms such as ldb. Since no single form of map or representation is entirely satisfactory for all purposes the maps reproduced in the published version of the report are confined to one of the genetic maps, in which Genethon and older markers have been incorporated, a Sigma map of the genes as symbols together with a listing of known 'disease' genes on chromosome 9, and a revised assessment of the mouse map together with a list of mouse loci predicted to be on human chromosome 9. One of the 25 ACEDB slices is also shown to illustrate strengths and weaknesses of this approach. Workshop files include not only all maps available at the time but also details of loci and details of the meiotic breakpoints in the CEPH families.

The Fifth International workshop on chromosome 9 comprised a gathering of 36 scientists from seven countries and included a fairly even distribution of interests along chromosome 9 as well as a strong input from more global activities and from comparative mapping. At least eight groups had participated in the goal set at the previous workshop which was to improve the fine genetic mapping in different regions of chromosome 9 by meiotic breakpoint mapping in allocated regions and this has resulted in some greatly improved order information. Excellent computing facilities were available and all contributed maps were entered not only into SIGMA (and thence submitted to GDB) but also into a dedicated version of ACEDB which can be accessed on the Web in the form of one of 28 slices into which the chromosome has been arbitrarily divided. It was generally agreed that the amount of data is now overwhelming and that the integration and validation of all data is not only unrealistic in a short meeting but probably impossible until the whole chromosome has been sequenced and fully annotated. Sequence-ready contigs presented at the meeting totalled about 3 MB which is about one fiftieth of the estimated length. The single biggest barrier to integration of maps is the problem of non-standard nomenclature of loci. In the past 2 workshops efforts have been made to compare traditional 'consensus' maps made by human insight (still probably best for small specific regions) with those generated with some computer assistance (such as SIGMA) and those generated objectively by defined computer algorithms such as ldb. Since no single form of map or representation is entirely satisfactory for all purposes the maps reproduced in the published version of the report are confined to one of the genetic maps, in which Genethon and older markers have been incorporated, a Sigma map of the genes as symbols together with a listing of known 'disease' genes on chromosome 9, and a revised assessment of the mouse map together with a list of mouse loci predicted to be on human chromosome 9. One of the 25 ACEDB slices is also shown to illustrate strengths and weaknesses of this approach. Workshop files include not only all maps available at the time but also details of loci and details of the meiotic breakpoints in the CEPH families.

[Display omitted] • HSI-DFM can visualize and quantify the cellular accumulation of NPs. • The hyperspectral library was constructed and optimized based on intracellular NPs. • The accuracy of HSI-DFM was verified by fluorescence microscopy and flow cytometry. • HSI-DFM can determine the accumulation kinetics of NPs in single living cells. • HSI-DFM can also be applied to different cell lines and different NPs. Nanoplastic (NP) pollution is receiving increasing attention regarding its potential effects on human health. The identification and quantification of intracellular NPs are prerequisites for an accurate risk assessment, but appropriate methods are lacking. Here we present a label-free technique to simultaneously visualize and quantify the bioaccumulation of NPs based on hyperspectral imaging with enhanced dark-field microscopy (HSI-DFM). Using polystyrene NPs (PS NPs) as representative particles, the construction of a hyperspectral library was optimized first with more accurate NP identification achieved when the library was based on intracellular instead of extracellular PS NPs. The PS NPs used herein were labeled with a green fluorescent dye so that the accuracy of HSI-DFM in identifying and quantifying intracellular NPs can be evaluated, by comparing the results with those obtained by fluorescence microscopy and flow cytometry. The validation of HSI-DFM for use in determinations of the NP concentration at the single-cell level allows analyses of the accumulation kinetics of NPs in single living cells. The utility of HSI-DFM in different cell lines and with NPs differing in their chemical composition was also demonstrated. HSI-DFM therefore provides a new approach to studies of the accumulation and distribution of NPs in human cells. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder with a great degree of phenotypic variability. Given the presence of two gene loci underlying this disorder, locus heterogeneity may account for some of the variability. However, significant within family variation suggests that different genes do not explain the majority of this variation. The purpose of this research is to identify physical and behavioural variation in expression of TSC in a single large extended kindred. TSC in this kindred is cosegregating with markers localised to chromosome 16p13.3. The expression of TSC in this kindred is quite variable with a substantial proportion of persons showing very mild physical expression of TSC. In contrast to very mild physical expression of TSC in some family members, there is a significant clustering of psychiatric disorders among persons affected with TSC compared to their unaffected relatives. This finding, coupled with the mild physical expression of TSC in some family members, supports a hypothesis that the TSC2 gene may present phenotypically as mild skin signs and significant behavioural problems.

Normal human melanocytes require 12-O-tetradecanoylphorbol 13-acetate (TPA) for prolonged growth in vitro. In contrast, the growth of human malignant melanoma cells is often inhibited by TPA. In this study, we have confirmed and extended these observations. Since protein kinase C (PKC) is an important mediator of the effects of TPA, we have investigated the nature of this differential growth response by examining PKC expression and activity in primary cultures of human neonatal melanocytes and metastatic melanoma cell strains. PKC, when measured by immunoreactivity or a functional assay, was found to be more abundant in melanoma cells than in melanocytes. When specific isotypes were examined by Northern analysis, PKC-alpha and -epsilon were expressed in both melanocytes and melanoma. PKC-beta was expressed in melanocytes, but was undetectable by Northern analysis in 10 out of 11 melanoma cell strains. Southern analysis revealed that no gross deletions or rearrangements of the PKC-beta gene had occurred. These data suggest that down-regulation of the PKC-beta gene occurs frequently during the process of transformation of melanocytes. Furthermore, differential expression of PKC isotypes may explain the different effects of TPA on melanocyte and melanoma cell growth.

Cultivation of human melanocytes requires several growth factors for cell proliferation. For example, basic fibroblast growth factor (bFGF) is an essential growth agent for melanocyte proliferation in vitro and has been proposed to be an autocrine growth factor in human melanoma cells. Studies using either anti-bFGF antibodies or antisense oligonucleotides partially inhibited the proliferation of human melanoma cells. However, one group was unable to detect bFGF RNA transcripts in human melanoma cells using a human complementary DNA probe. These contradictory results prompted us to investigate the bFGF gene expression in human primary melanocytes and metastatic melanoma cells using Southern, Northern, and Western blot analyses. No gross rearrangements in the bFGF gene were detected in the genomic DNA. Although high levels of bFGF RNA transcripts were detected in melanocytes, no bFGF protein was detected using Western blot analysis. In contrast, melanoma cells expressed much lower levels of bFGF RNA transcripts, and cells from three of four cell strains synthesized the multiple isoforms of bFGF protein. In one of the melanoma cell strains, no bFGF protein was detected using Western blot analysis. Although three of four melanoma cell strains expressed bFGF protein, this molecule does not appear to function as an autocrine growth factor, and expression of the bFGF protein was not a consistent alteration in all melanoma cell strains.

Though widely used by business, industry, academia, and social service agencies as a mass communication vehicle, the effectiveness of newsletters has received limited critical review. The sound research base needed to support the use of newsletters in cancer prevention interventions was not found in the literature. This article details the development, design, use and evaluation of a health behavior model-based monthly newsletter for participants in three community-oriented cancer prevention studies. Depending on the extent of behavior change asked of them, participants reported reading 60-100% of the content. Participants in the three different cancer prevention interventions perceived the newsletters to be informative, accurate, and interesting. Costing as little as $0.36 per participant per issue, this strategy has implications for other types of field studies with similarly educated participants. The adherencepromotion strategy, of which the newsletters were a part, kept the participants in field studies long enough to test the study hypotheses and potentially improve their health, and reduce morbidity and mortality. © 1991.

The hereditary human disease ataxia-telangiectasia (AT) is characterized by phenotypic complexity at the cellular level. We show that multiple mutant phenotypes of immortalized AT cells from genetic complementation group D (AT-D) are corrected after the introduction of a single human chromosome from a human-mouse hybrid line by microcell-mediated chromosome transfer. This chromosome is cytogenetically abnormal. It consists primarily of human chromosome 18, but it carries translocated material from the region 11q22-23, where one or more AT genes have been previously mapped by linkage analysis. A cytogenetically normal human chromosome 18 does not complement AT-D cells after microcell-mediated transfer, whereas a normal human chromosome 11 does. We conclude that the AT-D gene is located on chromosome 11q22-23.