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The paper highlights how significant characteristics of liver can be modeled in tissue-engineered constructs using unconventional scaffolds. Hepatic lobular organization and metabolic zonation can be mimicked with decellularized plant structures with vasculature resembling a native-hepatic lobule vascular arrangement or silk blend scaffolds meticulously designed for guided cellular arrangement as hepatic patches or metabolic activities. The functionality of hepatocytes can be enhanced and maintained for long periods in naturally fibrous structures paving way for bioartificial liver development. The phase I enzymatic activity in hepatic models can be raised exploiting the microfibrillar structure of paper to allow cellular stacking creating hypoxic conditions to induce in vivo -like xenobiotic metabolism. Lastly, the paper introduces amalgamation of carbon-based nanomaterials into existing scaffolds in liver tissue engineering.

Development of cheap and portable 3D liver models is a need of an hour for drug screening applications in the healthcare and diagnostic sector. An appropriate 3D liver model would support adhesion, proliferation, viability and functionality of the liver cells. With this perspective, the present study delineates the fabrication and characterization of PAMAM conjugated cellulose filter paper-based 3D liver model. Due to the absence of any cell adhesion motif, paper cannot directly be used for cell culture applications, thus, it was functionalized with PAMAM dendrimer using glutaraldehyde. PAMAM derivatized paper (PF) supported significantly higher adhesion, proliferation, and viability of the HepG2 cells in comparison to non-functionalized paper. Moreover, HepG2 cells maintained their functional aspects i.e., expression of mature hepatocyte markers albumin, CK19, CYP3 A4, MDR1 and SULT2 A1 on PF. Further, we showed the application of the PF-based 3D liver model for drug toxicity evaluations against hepatotoxins. The results showed a significantly higher sensitivity of the HepG2 cells in paper-based 3D culture as compared to 2D monolayer culture, which is similar to that of physiological drug-induced responses. In conclusion, PAMAM functionalized filter paper could serve as an efficient biomaterial platform for the development of microscale technologies, liver-associated diagnostics, and drug screening applications., (Copyright © 2018 Elsevier B.V. All rights reserved.)

This study investigates whether pulse exposure to Chilean pulp and paper mill effluent solid phase extracted (SPE) extracts via intraperitoneal injection (IP), would result in changes in the activities of the respiratory metabolic enzymes citrate synthase (CS) and lactate dehydrogenase (LDH) in rainbow trout livers. It also investigated if an alteration in liver metabolic capacity influenced the liver detoxification processes and estrogenic effects previously reported. Besides, a comparison of those enzymatic activities with fish IP injected with SPE extracts of two model effluents coming from industries that process 100% different type of feedstock (softwood, SW and hardwood, HW) was also evaluated. An initial induction of the anaerobic metabolism (increase in LDH enzymatic activity) was detected in all Chilean pulp mill effluent extracts evaluated, contrary to the initial unaltered aerobic metabolism (CS enzymatic activity) observed. A compensatory relationship in energy metabolism (Pasteur effect) was observed when comparing both enzymatic activities of fish exposed to those effluent extracts. LDH and CS activities observed in fish injected with Chilean extracts seem to be related to the effects observed in fish injected with SW extracts. This study showed that intraperitoneal injection of pulp and paper mill effluent extracts affected the anaerobic and aerobic metabolic capacities in rainbow trout livers, but this metabolic alteration did not affect detoxification capability or estrogenic effect previously reported., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Wood extractives present in pulp and paper mill effluents may cause reproductive disturbances in fish. A chronic-exposure toxicity experiment using immature rainbow trout (Oncorhynchus mykiss) was conducted in order to assess the endocrine disrupting effects of two Chilean pulp and paper mill specific extracts (solid phase extraction, SPE) obtained from primary and secondary treated effluents. The (anti)estrogenic potencies and toxicity of the wood extractives regularly present in pulp mill effluent such as dehydroabietic acid (DHAA), beta-sitosterol (BS), and model estrogen 17beta-estradiol (E2) were evaluated by analysis of plasma vitellogenin (VTG) levels, gonadal somatic index (GSI) and liver ethoxyresorufin-O-deethylase (EROD) activity, respectively. The protocol involved the use of multiple intra-peritoneal injections (1 injection every 7 days for a total exposure period of 28 days). Analysis of variance/covariance, demonstrated no differences associated with fish gender other than GSI. The phytosterol BS, E2 and both pulp mill effluent extracts showed significant inductions of EROD and increased VTG levels after 4, 7, 14, 21 and 28 of exposure. While fish injected with secondary treated effluent extract showed a delayed induction in VTG levels compared to primary effluent injected fish, no effects on VTG and EROD levels were observed in DHAA injected fish. Moreover simultaneous injection of DHAA+E2 reduced the VTG levels found in E2 injected fish, indicating a potential indirect anti-estrogenic effect of this resin acid. The results of this study indicate that Chilean pulp and paper mill effluent extracts are estrogenic in rainbow trout males and females., ((c) 2010 Elsevier B.V. All rights reserved.)

Despite numerous studies on microplastics, the biological impacts of polypropylene microplastics (PP-MPs) and its toxicity on freshwater fish have yet to be fully revealed. The purpose of this research was to look at the potentially harmful effects of PP-MPs in freshwater African catfish Clarias gariepinus and bioremediation using Spirulina. After acclimatization to laboratory conditions, 108 fish (125 ± 3 gm and 27 ± 2 cm) were assigned into triplicate six experimental groups (12 fish/group), a control group, Spirulina group (SP), PP-MP-treated groups (0.14 and 0.28 mg/l PP-MPs), and PP-MP + Spirulina-treated groups (0.14 mg/l PP-MPs + 200 mg/L SP and 0.28 mg/l PP-MPs +200 mg/L SP) for 15-day exposure and 45-day recovery after that. The hematological parameters exhibiting significance (RBCs, Hct, Hb, and MCV) or non-significance (MCH and MCHC) either decreased with the increase in PP-MP doses from 0.0 in the control to 0.28 mg/L red blood cells (RBCs), hematocrit (Hct), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), hemoglobin (Hb) and platelets or increased with such an increase in doses (mean corpuscular volume (MCV)). The liver enzyme activity, aspartate aminotransferase (AST), alkaline phosphatase (ALP), and alanine aminotransferase (ALT) exhibited non-significant (p ≥ 0.05) or significant (p < 0.05) increases in (0.14 and 0.28 mg/L) PP-MP-exposed groups, respectively, except ALP. Furthermore, there was a significant (p < 0.05) or non-significant (p ≥ 0.05) increase in 0.14 and 0.28 mg/l PP-MP +200 mg/L-exposure groups, respectively, compared to the control group and the same exposure group without Spirulina. In comparison to the control group, PP-MPs (0.14 and 0.28 mg/L) induced a significant (p < 0.05) increase in the percentage of poikilocytosis and nuclear abnormalities of RBCs. The liver tissue from fish exposed to PP-MPs exhibited varying degrees of pathological changes. These results indicated that these pathological changes increased with PP-MP concentration, suggesting that the effect of PP-MPs was dose-dependent. After 45 days of recovery under normal conditions, it was obvious that there was a significant improvement in the percentage of poikilocytosis and nuclear abnormalities of RBCs, as well as a non-significant improvement in hemato-biochemical parameters and liver tissue.

Toxic effects of unbleached (sulfate or sulfite) and bleached (sulfate) paper mill effluents were studied in a primary culture of rainbow trout liver cells. The effluents and control water from a clean area were extracted with diethyl ether and added to the cultures dissolved in dimethyl sulfoxide. Plasma membrane integrity was studied by measuring lactate dehydrogenase (LDH) leakage. The cellular content of glutathione (GSH) was used as an indicator of oxidative stress and the formation of reactive intermediates. Dose-response studies indicated that unbleached effluents contained more potent toxic substances than bleached effluents. Both unbleached and bleached effluents contained organic diethyl ether-extractable substances which increased cytochrome P450-dependent 7-ethoxyresorufin-O-deethylase (EROD) activities. The inducing effects were seen at concentrations substantially lower than those decreasing GSH content and increasing LDH leakage. Possible EROD inducing substances in bleached effluents are chlorinated organic compounds. Inducing compounds in unbleached effluents are yet to be identified. Furthermore, at higher concentrations the effluents contained substances that inhibited the cytochrome P450 system. The results show that the trout primary hepatocyte cultures afford a convenient in vitro method for screening cytochrome P450 inducing components extracted from industrial effluents to investigate mechanisms by which wastewaters cause injury in cells.

Simple Summary: This review paper deals with incidentally found focal liver lesions (IFLLs) in otherwise healthy subjects, which is a frequent occurrence in daily practice. The clinical presentation and the imaging aspects play an important role in deciding whether and what further evaluation is required. In low-risk patients (i.e., those without a history of malignant or chronic liver disease or related symptoms, younger than 40 years old), more than 95% of IFLLs are benign. Shear Wave liver Elastography of the surrounding liver parenchyma should be considered to exclude liver cirrhosis and for further risk stratification. If an IFLL in a low-risk patient has a typical appearance on a B-mode ultrasound of a benign lesion, no further imaging is needed. Contrast-Enhanced Ultrasound (CEUS) should be considered as the first-line contrast imaging modality to differentiate benign from malignant IFLLs. In high-risk patients (i.e., with chronic liver disease or an oncological history), each IFLL should initially be considered as potentially malignant, and every effort should be made to confirm or exclude malignancy. An incidental focal liver lesion (IFLL) is defined as a hepatic lesion identified in a patient imaged for an unrelated reason. They are frequently encountered in daily practice, sometimes leading to unnecessary, invasive and potentially harmful follow-up investigations. The clinical presentation and the imaging aspects play an important role in deciding if, and what further evaluation, is needed. In low-risk patients (i.e., without a history of malignant or chronic liver disease or related symptoms), especially in those younger than 40 years old, more than 95% of IFLLs are likely benign. Shear Wave liver Elastography (SWE) of the surrounding liver parenchyma should be considered to exclude liver cirrhosis and for further risk stratification. If an IFLL in a low-risk patient has a typical appearance on B-mode ultrasound of a benign lesion (e.g., simple cyst, calcification, focal fatty change, typical hemangioma), no further imaging is needed. Contrast-Enhanced Ultrasound (CEUS) should be considered as the first-line contrast imaging modality to differentiate benign from malignant IFLLs, since it has a similar accuracy to contrast-enhanced (CE)-MRI. On CEUS, hypoenhancement of a lesion in the late vascular phase is characteristic for malignancy. CE-CT should be avoided for characterizing probable benign FLL and reserved for staging once a lesion is proven malignant. In high-risk patients (i.e., with chronic liver disease or an oncological history), each IFLL should initially be considered as potentially malignant, and every effort should be made to confirm or exclude malignancy. US-guided biopsy should be considered in those with unresectable malignant lesions, particularly if the diagnosis remains unclear, or when a specific tissue diagnosis is needed. [ABSTRACT FROM AUTHOR]

Juvenile whitefish (Coregonus lavaretus L. s.l.) were exposed by caging in the field to diluted effluents from three operating pulp, paper, and paperboard mills in Southern Lake Saimaa, Finland. The expression of the vitellogenin gene, used as a biomarker of estrogenic contamination of effluents, was measured using a Northern blotting method. Increased mRNA levels, the most specific and reliable evidence for estrogen receptor-mediated actions in vivo, were found in fish caged in the vicinity of one of three mills studied. This mill was found to discharge wood-derived compounds, such as sterols and resin acids, into Lake Saimaa in amounts considerably exceeding those from the other two mills. The increased vitellogenin gene expression suggests that the effluent is a source of estrogenic contaminants., (Copyright 1999 Academic Press.)

Many studies link pulp and paper mill effluent (PPME) exposure to adverse effects in fish populations present in the mill receiving environments. These impacts are often characteristic of endocrine disruption and may include impaired reproduction, development and survival. While these physiological endpoints are well-characterized, the molecular mechanisms causing them are not yet understood. To investigate changes in gene transcription induced by exposure to a PPME at several stages of treatment, male and female fathead minnows (FHMs) were exposed for 6 days to 25% (v/v) secondary (biologically) treated kraft effluent (TK) or 100% (v/v) combined mill outfall (CMO) from a mill producing both kraft pulp and newsprint. The gene expression changes in the livers of these fish were analyzed using a 22K oligonucleotide microarray. Exposure to TK or CMO resulted in significant changes in the expression levels of 105 and 238 targets in male FHMs and 296 and 133 targets in females, respectively. Targets were then functionally analyzed using gene ontology tools to identify the biological processes in fish hepatocytes that were affected by exposure to PPME after its secondary treatment. Proteolysis was affected in female FHMs exposed to both TK and CMO. In male FHMs, no processes were affected by TK exposure, while sterol, isoprenoid, steroid and cholesterol biosynthesis and electron transport were up-regulated by CMO exposure. The results presented in this study indicate that short-term exposure to PPMEs affects the expression of reproduction-related genes in the livers of both male and female FHMs, and that secondary treatment of PPMEs may not neutralize all of their metabolic effects in fish. Gene ontology analysis of microarray data may enable identification of biological processes altered by toxicant exposure and thus provide an additional tool for monitoring the impact of PPMEs on fish populations., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The feasibility of using liver impressions on Flinders Technology Associates (FTA filter paper for the collection, inactivation, and molecular analysis of fowl adenovirus (FAV) was evaluated. FAV I European Union (EU) serotype 1 spotted on FTA was shown to be inactivated using specific-pathogen-free (SPF) primary chicken embryo liver cell culture as indicated by absence of cytopathic effect. Sensitivity of the polymerase chain reaction (PCR) test using tenfold dilutions of allantoic fluid from 100 to 10-4 for the detection of adenovirus serotype 1 on FTA cards was determined to be 0.0005 mean tissue culture infectious dose per FTA spot. The stability of the DNA from liver impressions on the FTA was found to be 198 days when stored at -20 degrees C. In a trial, inclusion body hepatitis (IBH) was experimentally reproduced in SPF chickens inoculated with FAV I EU serogroup 1, 4, 8, or 11, which presented weakness, pallor, depression, dehydration, and mortality within 6 days after inoculation. PCR performed on FTA liver impressions from the inoculated birds was able to detect all four viruses, and the nucleotide sequence analysis of the amplified PCR products (1219 bp of the hexone gene) revealed the expected serotypes. In addition to the trial, 55 clinical samples were analyzed from liver impressions on FTA cards, and FAV was detected in 11 of 55 (20%). Sequencing analysis showed that the viruses were EU serotypes 4, 5, 9, and 10. The results demonstrate that FTA filter paper inactivates the FAV I and maintains the DNA template for molecular analysis.

The studies were performed on perch (Perca fluviatilis) caught outside Husum and Iggesund kraft pulp mills in 1985 and 1987, respectively, and the results were compared to previous observations from 1984 to 1985 in the receiving waters of the Norrsundet kraft pulp mill. The studies revealed that the biochemical and physiological variables, i.e., EROD activity, gonad size, number of lymphocytes, carbohydrate metabolites, and plasma ion composition, can be used as sensitive and reliable indicators of toxic effects on natural populations of fish exposed to conventional chlorine-bleached kraft mill effluents. However; the effects were generally less pronounced and indicated less geographic extension than those seen in perch previously investigated in the receiving waters of the Norrsundet kraft pulp mill. Based on these studies on perch at Husum and Iggesund and the previous studies at Norrsundet it can be concluded that the chlorine-bleached kraft mill effluents cause serious disturbances to vital biochemical and physiological functions, which can affect the health status and presumably also the survival of the fish. Finally, the responses do not reflect the present situation in the receiving waters since all three mills have taken extensive measures for process alterations and discharge reductions after the time of the investigations.

Summary: During the early stages of the coronavirus disease 2019 (COVID-19) pandemic, EASL and ESCMID published a position paper to provide guidance for physicians involved in the care of patients with chronic liver disease. While some healthcare systems are returning to a more normal routine, many countries and healthcare systems have been, or still are, overwhelmed by the pandemic, which is significantly impacting on the care of these patients. In addition, many studies have been published focusing on how COVID-19 may affect the liver and how pre-existing liver diseases might influence the clinical course of COVID-19. While many aspects remain poorly understood, it has become increasingly evident that pre-existing liver diseases and liver injury during the disease course must be kept in mind when caring for patients with COVID-19. This review should serve as an update on the previous position paper, summarising the evidence for liver disease involvement during COVID-19 and providing recommendations on how to return to routine care wherever possible.

Lentiviral vectors (LV) are efficient vehicles for in vivo gene delivery to the liver. LV integration into the chromatin of target cells ensures their transmission upon proliferation, thus allowing potentially life-long gene therapy following a single administration, even to young individuals. The glycoprotein of the vesicular stomatitis virus (VSV.G) is widely used to pseudotype LV, as it confers broad tropism and high stability. The baculovirus-derived GP64 envelope protein has been proposed as an alternative for in vivo liver-directed gene therapy. Here, we perform a detailed comparison of VSV.G- and GP64-pseudotyped LV in vitro and in vivo. We report that VSV.G-LV transduced hepatocytes better than GP64-LV, however the latter showed improved transduction of liver sinusoidal endothelial cells (LSEC). Combining GP64-pseudotyping with the high surface content of the phagocytosis inhibitor CD47 further enhanced LSEC transduction. Coagulation factor VIII (FVIII), the gene mutated in hemophilia A, is naturally expressed by LSEC, thus we exploited GP64-LV to deliver a FVIII transgene under the control of the endogenous FVIII promoter and achieved therapeutic amounts of FVIII and correction of hemophilia A mice., (© 2024. The Author(s).)

Adult eels (Anguilla anguilla L.) were exposed for 8, 16, 24, and 72 h to 0, 0.1, 0.3, 0.9, and 2.7 microM abietic acid (AA). Genotoxicity was measured as erythrocytic nuclear abnormalities (ENA), as well as DNA strand breaks in blood and liver. Liver cytochrome P450 (P450) content, liver ethoxyresorufin O-deethylase (EROD), and glutathione S-transferase (GST) activities were determined as biotransformation biomarkers. Liver alanine transaminase (ALT) activity was also measured as an indication of tissue damage. Low AA concentrations, such as 0.1 and 0.3 microM, result in a delayed induction of A. anguilla L. liver EROD activity, whereas the higher AA concentration (2.7 microM AA) also has a delayed effect probably as a consequence of liver tissue high inhibitory concentration. The current eel liver GST activity results demonstrate that only low AA concentrations promote liver increases in GST, whereas high AA concentrations, such as 0.9 and 2.7 microM, do not alter it. The results concerning eel liver ALT activity indicate that significant liver damage is induced by high AA concentrations, such as 2.7 and 0.9 microM. The eel ENA result analysis reveals that AA is a weak ENA inducer in A. anguilla L. Blood DNA integrity results suggest that low AA concentrations promote late decreases in blood DNA integrity; nevertheless, high AA concentrations are early blood genotoxic inducers compared with low AA doses. According to the present research results with respect to eel liver DNA damage, all of the AA exposure concentrations decreased liver DNA integrity.

Rainbow trout (Salmo gairdneri) were exposed for 10 and 30 days to microbiologically treated effluent of a bleached kraft pulp and paper mill (BKME). Throughout the experiments, the quality of dilution water, taken from an upstream location close to the mill, was allowed to vary both diurnally and seasonally (September-October) in a natural manner. The test concentrations averaged 0 (control), 0.6, 1.2, 2.0, and 5.1% (v/v) of BKME. Conjugates of all major resin acids and chlorinated phenolics of BKME, except chlorocatechols, were detected in trout bile. They comprised 93.1-99.9% of the total amounts in the bile. The level of conjugated resin acids increased linearly with the content of BKME in test water. On the other hand, no increase in concentration of conjugated phenolics was seen above 2.0% BKME. In the blood plasma no conjugates were analyzable. Concentrations of free resin acids in the blood plasma, but not in the bile, significantly increased at high test concentrations of BKME. No active excretion of free resin acids from plasma to bile can be inferred, but some of the phenolics--particularly 3,4,5,6-tetrachloroguaiacol--seem to be concentrated in the bile as a free compound. Changes in several biochemical parameters did not display any simple relationship with the external concentrations of BKME. In intermediate exposure concentrations, however, liver RNA and protein concentrations were decreased after 10 days but increased after 30 days. Condition of fish, relative size of the liver, and concentrations of liver glycogen and water were unresponsive to BKME at the dilutions investigated.

In a laboratory investigation, fourhorn sculpin (Myoxocephalus quadricornis) were exposed for 5-9 months to waste water from pine and birch lines from a bleached kraft pulp plant. The bleached kraft mill effluents (BKME) affected both the carbohydrate metabolism and the xenobiotic metabolism. Thus, an elevated muscle glycogen content in fish exposed to effluent from the pine pulp line suggests a metabolic imbalance. A liver enlargement and a strong elevation of the hepatic cytochrome P-450-dependent ethoxyresorufin-O-deethylase activity after exposure to the bleached pine pulp effluents indicate the presence of cytochrome P-450-inducing agents in the BKME. The results also demonstrate that many physiological test parameters may be used as good indicators of sublethal disturbances in fish to BKME exposure.

Background: In carnitine palmitoyltransferase I (CPT-I) deficiency (MIM 255120), free carnitine can be increased with no pathologic acylcarnitine species detectable. As inclusion of CPT-I deficiency in high-risk and newborn screening could prevent potentially life-threatening complications, we tested whether CPT-I deficiency might be diagnosed by electrospray ionization-tandem mass spectrometry (ESI-MS/MS)., Methods: A 3.2-mm spot of whole blood dried on filter paper was extracted with 150 microL of methanol. After derivatization of carnitine and acylcarnitines to their butyl esters, the samples were analyzed by ESI-MS/MS with 37.5 pmol of L-[(2)H(3)]carnitine and 7.5 pmol of L-[(2)H(3)]palmitoylcarnitine as internal standards., Results: In all dried-blood specimens from each of three patients with CPT-I deficiency, we found an invariably increased ratio of free carnitine to the sum of palmitoylcarnitine and stearoylcarnitine [C0/(C16 + C18)]. The ratio in patients was between 175 and 2000, or 5- to 60-fold higher than the ratio for the 99.9th centile of the normal newborn population in Bavaria (n = 177 842). No overlap with the values of children that were known to be supplemented with carnitine was detected [C0/(C16 + C18), 34 +/- 30; mean +/- SD; n = 27]., Conclusions: ESI-MS/MS provides a highly specific acylcarnitine profile from dried-blood samples. The ratio of free carnitine to the sum of palmitoylcarnitine and stearoylcarnitine [C0/(C16 + C18)] is highly specific for CPT-I deficiency and may allow presymptomatic diagnosis.

A glycan chain analysis of the total oligosaccharide pool derived from rat liver arylsulfatase B was carried out by. P4 Gel Permeation Chromatography and sequential exoglycosidase digestion. It was found that 71% of rat liver arylsulfatase B oligosaccharides were sialylated. The relative contribution of particular structures in the total glycan pool was as follows: sialylated biantennary complex type glycans with terminal galactose--65%, high-mannose type glycans--15%, biantennary complex type glycans with core fucose and terminal N-acetylglucosamine--5%, O-linked oligosaccharides--3.5%.

Heart failure—either with reduced or preserved ejection fraction (HFrEF/HFpEF)—is a clinical syndrome of multifactorial and gender-dependent aetiology, indicating the insufficiency of the heart to pump blood adequately to maintain blood flow to meet the body's needs. Typical symptoms commonly include shortness of breath, excessive fatigue with impaired exercise capacity, and peripheral oedema, thereby alluding to the fact that heart failure is a syndrome that affects multiple organ systems. Patients suffering from progressed heart failure have a very limited life expectancy, lower than that of numerous cancer types. In this position paper, we provide an overview regarding interactions between the heart and other organ systems, the clinical evidence, underlying mechanisms, potential available or yet-to-establish animal models to study such interactions and finally discuss potential new drug interventions to be developed in the future. Our working group suggests that more experimental research is required to understand the individual molecular mechanisms underlying heart failure and reinforces the urgency for tailored therapeutic interventions that target not only the heart but also other related affected organ systems to effectively treat heart failure as a clinical syndrome that affects and involves multiple organs. [ABSTRACT FROM AUTHOR]

Endogenous acceptors in a Golgi apparatus-enriched subcellular fraction from rat liver were labeled with UDP-[3H]GalNAc. The great majority of these acceptors were protected from protease degradation in the absence of detergent. These molecules are therefore present in intact vesicles of the correct topological orientation, which are likely to be similar to the Golgi compartments of the intact cell. Several distinct glycoproteins are labeled, but most are different from those labeled with UDP-[3H]GlcNAc. The enzyme peptide-N4(N-acetyl-beta-glucosiminyl)asparagine amidase releases label from a few specific proteins, indicating that [3H]GalNAc is transferred to N-linked oligosaccharides. Both neutral and anionic N-linked oligosaccharides are found, the great majority of which do not bind to ConA-Sepharose. Most of the [3H]GalNAc found in neutral oligosaccharides is terminal and beta-linked. The negative charge on the anionic molecules is due to sialic acid, and phosphate. A major portion of the [3H] GalNAc in this fraction is acid labile, and is released with kinetics consistent with it being in a phosphodiester linkage. These results show the existence of a whole new class of GalNAc-containing N-linked oligosaccharides, and demonstrates that this in vitro approach can detect previously undescribed structures. O-linked oligosaccharide biosynthesis was also studied in the same labeled rat liver Golgi apparatus preparations. beta-Elimination releases approximately 95% of the peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase (PNGase F)-resistant label which, in the absence of other added nucleotides, is almost exclusively [3H] GalNAcitol. If other unlabeled sugar nucleotides and adenosine 3'-phosphate,5'-phosphosulfate are added during the chase period two anionic O-linked oligosaccharides are synthesized, indicating that the UDP-GalNAc:peptide-N-acetylgalactosaminyltransferase is at least in part functionally co-localized with enzymes that extend and modify O-linked oligosaccharides.

Human serum alpha-fetoprotein (AFP) is elevated in not only hepatocellular carcinoma (HCC) but also benign liver diseases. AFP produced in HCC and benign liver diseases was separated into several isoforms corresponding to different sugar chain structures by several types of lectin affinity electrophoresis, and the HCC-specific AFP isoform was discriminated from those of benign liver diseases. Because a small amount of HCC-specific AFP isoform was detected in cord serum AFP, the whole sugar chain structures of human cord serum AFP were determined, as follows: Neu5Ac alpha 2-->Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->6(Neu5Ac alpha 2 -->6Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->3)Man beta 1-->4R1 and R2, Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->6(Neu5Ac alpha 2-->6Gal beta 1 -->4GlcNAc beta 1-->2Man alpha 1-->3)Man beta 1-->4R1 and R2, and Neu5Ac alpha 2-->3Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->6(Neu5Ac alpha 2 -->6Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->3)Man beta 1-->4R1 and R2 in the ratio of 81.6:8.9:9.5. R1 and R2 denote GlcNAc beta 1-->4GlcNAcOT (subscript OT represents an NaB3H4-reduced oligosaccharide) and GlcNAc beta 1-->4(Fuc alpha 1-->6)GlcNAcOT, respectively, and the ratio between R1 and R2 in the respective fractions was approximately 19:1. In contrast, the sugar chain structure of HCC highly specific AFP isoform was found to comprise a monosialyl-biantennary sugar chain with additional fucosylation of the proximal N-acetylglucosamine. Fucosylation of AFP produced in fetal liver increased in inverse proportion to the gestation period, in weeks, indicating that fucosylation of AFP in HCC may be related to the dedifferentiation of human hepatocytes through malignant transformation.

Male CD rats were injected with single i.p. doses of benzo(a)pyrene (B(a)P), and peripheral blood lymphocytes (PBLs), livers, and lungs were removed at various times after administration. DNA adducts were analyzed in each tissue by 32P postlabeling with nuclease P1 enhancement. Sister chromatid exchange frequencies were concomitantly measured in cultured whole blood. B(a)P-DNA adducts were observed in all three tissues from animals sacrificed between 1 and 56 days after injection. Maximal adduction levels occurred at about 4 days after administration, followed by a gradual loss of adducts over the period examined. The apparent half-lives of total DNA adducts were 15 days in liver, 17 days in PBLs, and 22 days in lung. Induced sister chromatid exchanges were linearly related to the amount of DNA adducts remaining in the PBLs at the time of harvest up to 56 days and were significantly elevated above concurrent controls up to 14 days. One of the major adducts found in each tissue was N2-(10 beta-[7 beta,8 alpha,9 alpha-trihydroxy-7,8,9,10-tetrahydrobenzo(a) pyrene]yl)deoxyguanosine. An additional novel major adduct was found in the liver DNA and is derived from the further metabolism of B(a)P-trans-7,8-dihydrodiol. A second major novel B(a)P adduct was found in the DNA of lung tissues and accounts for about 40% of the total adducts present. Experimental evidence suggests that this adduct is derived from a metabolic pathway that includes the formation of 9-hydroxy-B(a)P.

Despite numerous studies on microplastics, the biological impacts of polypropylene microplastics (PP-MPs) and its toxicity on freshwater fish have yet to be fully revealed. The purpose of this research was to look at the potentially harmful effects of PP-MPs in freshwater African catfish Clarias gariepinus and bioremediation using Spirulina. After acclimatization to laboratory conditions, 108 fish (125 ± 3 gm and 27 ± 2 cm) were assigned into triplicate six experimental groups (12 fish/group), a control group, Spirulina group (SP), PP-MP-treated groups (0.14 and 0.28 mg/l PP-MPs), and PP-MP + Spirulina-treated groups (0.14 mg/l PP-MPs + 200 mg/L SP and 0.28 mg/l PP-MPs +200 mg/L SP) for 15-day exposure and 45-day recovery after that. The hematological parameters exhibiting significance (RBCs, Hct, Hb, and MCV) or non-significance (MCH and MCHC) either decreased with the increase in PP-MP doses from 0.0 in the control to 0.28 mg/L red blood cells (RBCs), hematocrit (Hct), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), hemoglobin (Hb) and platelets or increased with such an increase in doses (mean corpuscular volume (MCV)). The liver enzyme activity, aspartate aminotransferase (AST), alkaline phosphatase (ALP), and alanine aminotransferase (ALT) exhibited non-significant (p ≥ 0.05) or significant (p < 0.05) increases in (0.14 and 0.28 mg/L) PP-MP-exposed groups, respectively, except ALP. Furthermore, there was a significant (p < 0.05) or non-significant (p ≥ 0.05) increase in 0.14 and 0.28 mg/l PP-MP +200 mg/L-exposure groups, respectively, compared to the control group and the same exposure group without Spirulina. In comparison to the control group, PP-MPs (0.14 and 0.28 mg/L) induced a significant (p < 0.05) increase in the percentage of poikilocytosis and nuclear abnormalities of RBCs. The liver tissue from fish exposed to PP-MPs exhibited varying degrees of pathological changes. These results indicated that these pathological changes increased with PP-MP concentration, suggesting that the effect of PP-MPs was dose-dependent. After 45 days of recovery under normal conditions, it was obvious that there was a significant improvement in the percentage of poikilocytosis and nuclear abnormalities of RBCs, as well as a non-significant improvement in hematobiochemical parameters and liver tissue. [ABSTRACT FROM AUTHOR]