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1.
Front Plant Sci ; 15: 1445786, 2024.
Article in English | MEDLINE | ID: mdl-39170781

ABSTRACT

Plant diseases caused by microbial pathogens pose a severe threat to global food security. Although genetic modifications can improve plant resistance; however, environmentally sustainable strategies are needed to manage plant diseases. Nano-enabled immunomodulation involves using engineered nanomaterials (ENMs) to modulate the innate immune system of plants and enhance their resilience against pathogens. This emerging approach provides unique opportunities through the ability of ENMs to act as nanocarriers for delivering immunomodulatory agents, nanoprobes for monitoring plant immunity, and nanoparticles (NPs) that directly interact with plant cells to trigger immune responses. Recent studies revealed that the application of ENMs as nanoscale agrochemicals can strengthen plant immunity against biotic stress by enhancing systemic resistance pathways, modulating antioxidant defense systems, activating defense-related genetic pathways and reshaping the plant-associated microbiomes. However, key challenges remain in unraveling the complex mechanisms through which ENMs influence plant molecular networks, assessing their long-term environmental impacts, developing biodegradable formulations, and optimizing targeted delivery methods. This review provides a comprehensive investigation of the latest research on nano-enabled immunomodulation strategies, potential mechanisms of action, and highlights future perspectives to overcome existing challenges for sustainable plant disease management.

2.
Article in English | MEDLINE | ID: mdl-38771456

ABSTRACT

This study evaluated the effects of Technospore® (Bacillus coagulans) supplementation on intestinal health, immune response, and Oreochromis niloticus (Nile tilapia) growth performance. The experiment divided fish into four groups: a control group fed an unsupplemented diet and three experimental groups receiving diets supplemented with 0.2 g/kg, 0.4 g/kg, and 0.8 g/kg of Technospore®, respectively. Results indicated that Technospore® supplementation significantly enhanced growth rates and feed efficiency in all treated groups, with the most pronounced improvements observed in the group receiving 0.4 g/kg. Furthermore, the study revealed that B. coagulans supplementation markedly boosted serum immune responses, as evidenced by increased phagocytic activity, phagocytic index, and lysozyme levels, following a challenge with Aeromonas hydrophila. Histological analysis showed improved gut morphology, while gene expression analysis indicated upregulation of immune-related genes, including liver IGF-1, GHR, HSP70, IL-1ß, and TNF-α, as well as spleen TNF-α and IL-1ß and intestinal C-lysozyme and TNF-α, both before and after the bacterial challenge. These findings suggest that dietary inclusion of Technospore® can significantly improve gut health and immune responses in tilapia, potentially serving as an effective prophylactic alternative to antibiotics in aquaculture.

3.
Front Plant Sci ; 15: 1321950, 2024.
Article in English | MEDLINE | ID: mdl-38292912

ABSTRACT

Introduction: Invasive species have been identified as a major threat to native biodiversity and ecosystem functioning worldwide due to their superiority in spread and growth. Such superiority is explained by the invasional meltdown phenomena, which suggests that invasive species facilitate the establishment of more invasive species rather than native species by modifying the plant-soil feedback (PSF). Methods: We conducted a two-phase plant-soil feedback experiment using the native Prosopis cineraria and the invasive Prosopis juliflora in Oman. Firstly, we conditioned the soil by planting seedlings of native species, invasive species, native and invasive species "mixed", and unconditioned soil served as a control. Secondly, we tested the feedback of these four conditioned soil on the two species separately by measuring the productivity (total biomass) and the performance in the form of plant functional traits (plant height, specific leaf area (SLA), leaf nitrogen content (Nmass), leaf carbon content (Cmass) and specific root length (SRL) of native and invasive species as well as the nutrient availability in soil (soil organic carbon (SOC) and soil total nitrogen (STN)). Results and discussion: We found that the native species produced more biomass, best performance, and higher SOC and STN when grown in soil conditioned by native species, additionally, it gave lower biomass, reduced performance, and lower SOC and STN when grown in the soil conditioned by invasive and mixed species. These results suggest negative PSF for native species and positive PSF for invasive species in the soil conditioned by invasive species, which can be considered as red flag concerning the restoration of P. cineraria as an important native species in Oman, as such positive PSF of the invasive species P. juliflora will inhibit the regeneration of P. cineraria.

4.
Plants (Basel) ; 12(11)2023 May 26.
Article in English | MEDLINE | ID: mdl-37299089

ABSTRACT

Heavy metal stress, including from chromium, has detrimental effects on crop growth and yields worldwide. Plant growth-promoting rhizobacteria (PGPR) have demonstrated great efficiency in mitigating these adverse effects. The present study investigated the potential of the PGPR strain Azospirillum brasilense EMCC1454 as a useful bio-inoculant for boosting the growth, performance and chromium stress tolerance of chickpea (Cicer arietinum L.) plants exposed to varying levels of chromium stress (0, 130 and 260 µM K2Cr2O7). The results revealed that A. brasilense EMCC1454 could tolerate chromium stress up to 260 µM and exhibited various plant growth-promoting (PGP) activities, including nitrogen fixation, phosphate solubilization, and generation of siderophore, trehalose, exopolysaccharide, ACC deaminase, indole acetic acid, and hydrolytic enzymes. Chromium stress doses induced the formation of PGP substances and antioxidants in A. brasilense EMCC1454. In addition, plant growth experiments showed that chromium stress significantly inhibited the growth, minerals acquisition, leaf relative water content, biosynthesis of photosynthetic pigments, gas exchange traits, and levels of phenolics and flavonoids of chickpea plants. Contrarily, it increased the concentrations of proline, glycine betaine, soluble sugars, proteins, oxidative stress markers, and enzymatic (CAT, APX, SOD, and POD) and non-enzymatic (ascorbic acid and glutathione) antioxidants in plants. On the other hand, A. brasilense EMCC1454 application alleviated oxidative stress markers and significantly boosted the growth traits, gas exchange characteristics, nutrient acquisition, osmolyte formation, and enzymatic and non-enzymatic antioxidants in chromium-stressed plants. Moreover, this bacterial inoculation upregulated the expression of genes related to stress tolerance (CAT, SOD, APX, CHS, DREB2A, CHI, and PAL). Overall, the current study demonstrated the effectiveness of A. brasilense EMCC1454 in enhancing plant growth and mitigating chromium toxicity impacts on chickpea plants grown under chromium stress circumstances by modulating the antioxidant machinery, photosynthesis, osmolyte production, and stress-related gene expression.

5.
Int J Oral Maxillofac Surg ; 52(5): 515-523, 2023 May.
Article in English | MEDLINE | ID: mdl-36123273

ABSTRACT

The aim of this study was to clarify the correlation between imaging findings obtained using intraoral ultrasonography (US) and pathological findings of tongue cancers, and to examine the predictive value of intraoral US findings with respect to occult nodal metastasis. This was a retrospective study based on the medical records of 123 patients with T1-2N0 tongue cancer. The depth of invasion (DOI) on intraoral US was positively correlated with the pathological invasion depth (PID) (ρ = 0.7080, P < 0.0001). Receiver operating characteristic analyses revealed an optimal DOI cut-off value of 4.1 mm and optimal PID cut-off value of 3.9 mm to detect nodal metastasis. Regarding the margin shape of the primary tumour on intraoral US, the incidence of nodal metastasis was significantly higher for the permeated type than for the pressure type (P < 0.001) and wedge-shaped type (P = 0.002). Furthermore, tumours with peritumoural vascularity assessed by power Doppler US had a significantly higher incidence of nodal metastasis than tumours without (P = 0.003). The sensitivity, specificity, and accuracy of the permeated type to predict nodal metastasis was 53.6%, 95.8%, and 86.2%, respectively. These results suggest that intraoral US findings closely reflect pathological findings and could be useful to predict occult nodal metastasis in patients with early-stage tongue cancer.


Subject(s)
Tongue Neoplasms , Humans , Tongue Neoplasms/diagnostic imaging , Retrospective Studies , Tongue , Angiography , Transforming Growth Factor beta , Ultrasonography
6.
Ecol Evol ; 12(9): e9296, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36177142

ABSTRACT

Ecosystem functions are heavily dependent on the functional composition of the plant community, i.e., the functional traits of plants forming the community. This, on the one hand, depends on plant occurrence, but on the other hand, depends on the intraspecific variability of functional traits of the species, which are influenced by climate and nutrient availability and affected by plant-plant interactions. To illustrate that, we studied the effects of drought and nitrogen addition (+ N), two important abiotic variables which are changing with ongoing global change, as well as their combined effect on the functional responses of grassland communities in semi-arid environments of Northern Africa comprising of natural and invasive species. We conducted an experiment where we planted three native species and one invasive plant species in artificial communities of five individuals per species per plot. We exposed these communities to four different treatments: a drought treatment, an N-addition treatment, the combination between drought and N-addition, as well as a control. To assess the performance of plants within treatments, we measured selected plant functional traits (plant height, specific leaf area [SLA], leaf dry matter content [LDMC], N content of the leaves [Nmass], specific root length [SRL], and root diameter) for all individuals occurring in our plots, and additionally assessed the above and belowground biomass for each plant individual. We found that the invasive species showed a higher performance (higher biomass accumulation, taller plants, higher SLA, Nmass, SRL, and root diameter as well as lower LDMC) than the native species under drought conditions. The invasive species was especially successful with the combined impact of drought + N, which is a likely scenario in ongoing global change for our research area. Thus, plant functional traits might be a key factor for the invasion success of plant species which will be even more pronounced under ongoing global change.

7.
Plants (Basel) ; 10(11)2021 Nov 09.
Article in English | MEDLINE | ID: mdl-34834774

ABSTRACT

Land-use changes have huge impacts on natural vegetation, especially megaprojects, as the vegetation layer is destroyed in the course of construction works affecting the plant community composition and functionality. This large-scale disturbance might be a gateway for the establishment of invasive plant species, which can outcompete the natural flora. In contrast, species occurring in the area before the construction are not able to re-establish. In this study, we analyzed the impact of a pipeline construction on a wetland nature reserve located in northern Egypt. Therefore, we analyzed the plant species occurrence and abundance and measured each plant species' traits before the construction in 2017 as well as on multiple occasions up to 2 years after the construction had finished on altogether five sampling events. We found that the construction activity led to the establishment of an invasive species which previously did not occur in the area, namely, Imperata cylindrica, whereas five species (Ipomoea carnea, Pluchea dioscoridis, Polygonum equisetiforme, Tamarix nilotica, and Typha domingensis) could not re-establish after the disturbance. The functionality of ecosystems assessed via the analysis of plant functional traits (plant height, specific leaf area, and leaf dry matter content) changed within species over all sampling events and within the community showing a tendency to approximate pre-construction values. Functional dispersion and Rao's quadratic diversity were higher after the megaproject than before. These findings are important to capture possible re-establishment and recovery of natural vegetation after construction and raise awareness to the impact of megaprojects, especially in areas which are high priority for conservation.

8.
Int J Oral Maxillofac Surg ; 50(2): 163-170, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32536459

ABSTRACT

Protease-activated receptor 1 (PAR1) is known as a thrombin receptor. Recent studies have reported PAR1 expression in various malignancies; however, its role in oral squamous cell carcinoma (OSCC) requires clarification. A previous study showed that down-regulation of ΔNp63, a homolog of p53, augments PAR1 expression in OSCC. In the present study, the association of PAR1 expression with clinicopathological findings in OSCC was examined retrospectively. Expression of PAR1, thrombin, and ΔNp63 was examined immunohistochemically in OSCC specimens. Patients were divided into three groups based on the expression pattern of PAR1 at the invasive front: group A, PAR1-negative in both cancer and stromal cells; group B, positive in stromal cells but negative in cancer cells; group C, positive in both cancer and stromal cells. Histologically high-grade tumours were significantly more common in group C. Patients in group C had the highest incidence rate of nodal metastasis (P<0.001) and a lower survival rate (P=0.085) than those in the other groups. At the invasive front, in group C, thrombin was expressed but ΔNp63 expression was weak. These results indicate that increased PAR1 expression in both cancer and stromal cells could be a useful predictive marker of nodal metastasis and that ΔNp63 is involved in regulating PAR1 expression.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Down-Regulation , Humans , Receptor, PAR-1/genetics , Receptor, PAR-1/metabolism , Retrospective Studies , Squamous Cell Carcinoma of Head and Neck
9.
J Environ Manage ; 169: 202-9, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26760443

ABSTRACT

Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes.


Subject(s)
Agriculture/methods , Environment , Soil , Models, Theoretical , Rain , Republic of Korea , Seasons
10.
Hematol Oncol Stem Cell Ther ; 5(1): 42-8, 2012.
Article in English | MEDLINE | ID: mdl-22446614

ABSTRACT

BACKGROUND AND OBJECTIVES: Many patients with relapsed metastatic breast cancer are pre-treated with taxanes and anthracyclines, which are usually given in the neoadjuvant/adjuvant setting or as first-line treatment for metastatic disease. The primary objective of this study was to determine the overall response rate for combination treatment with gemcitabine and cisplatin in patients with locally advanced or metastatic breast cancer who had relapsed after receiving one adjuvant/neoadjuvant or first-line metastatic chemotherapy regimen containing an anthracycline with/without a taxane. Secondary endpoints included duration of response, time to progression, one-year survival probability, and toxicity. DESIGN AND SETTING: A single-arm, open-label, phase 2 study conducted at 17 investigative sites in Egypt. PATIENTS AND METHODS: treatment consisted of gemcitabine (1250 mg/m2) on Days 1 and 8 and cisplatin (70 mg/m2) on Day 1 of each 21-day cycle. Treatment continued until disease progression or a maximum of 6 cycles. RESULTS: Of 144 patients all were evaluable for safety and 132 patients were evaluable for efficacy. The overall response rate was 33.3% and 45.5% of the patients with stable disease as their best response. The median time-to-progression was 5.1 months and the one-year survival probability was 73%. The most common grade 3/4 adverse events were nausea/vomiting (20.1%), neutropenia (19.4%), anemia (13.9%), asthenia (11.1%), diarrhea (9.7%), stomatitis (7.6%), leucopenia (7.6%), and thrombocytopenia (6.2%). twelve (8.3%) patients had serious adverse events. CONCLUSIONS: The results of this study indicate that gemcitabine and cisplatin were active and generally well tolerated in pretreated patients with locally advanced or metastatic breast cancer.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Neoplasm Recurrence, Local/drug therapy , Salvage Therapy , Adult , Aged , Anthracyclines/therapeutic use , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Cisplatin/administration & dosage , Cisplatin/adverse effects , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Female , Humans , Kaplan-Meier Estimate , Middle Aged , Neoplasm Metastasis , Gemcitabine
11.
Ann Hematol ; 81(4): 224-7, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11976826

ABSTRACT

We experienced a rare case of a lymphomatous polyp of mantle cell type forming a polypoid mass lesion in the duodenum bulbous together with advanced gastric cancer. A total gastrectomy was performed, and the specimen revealed atypical small- to medium-sized lymphoid cells with indented nuclei, which infiltrated the Peyer's patch and formed a nodular mass in the lamina propria and submucosa of the duodenum. The lymphoma cells also infiltrated the lymphoid follicle of the gastric mucosa, spleen, and regional lymph node with a typical mantle zone pattern. Flow cytometric analysis of the single cells of the lymph node and immunohistochemistry of a paraffin-embedded specimen revealed that the lymphoma cells expressed surface CD5, CD19, CD20, and nuclear cyclin D1. Chromosomal analysis of this single cell suspension revealed that these lymphoma cells have trisomy 3 in conjunction with t(11;14)(q13;q32), which is frequently seen in mucosa-associated lymphoid tissue lymphomas (MALToma) in the stomach and is also reported in mantle cell lymphoma as a secondary genetic alteration. Our report suggests that trisomy 3 may be a common chromosomal abnormality in lymphomatous polyps of mantle cell type.


Subject(s)
Chromosomes, Human, Pair 11 , Chromosomes, Human, Pair 14 , Duodenal Neoplasms/pathology , Intestinal Polyps/pathology , Lymphoma, Mantle-Cell/pathology , Stomach Neoplasms/pathology , Translocation, Genetic , Adenocarcinoma/diagnosis , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Chromosomes, Human, Pair 3 , Clone Cells/immunology , Clone Cells/pathology , Cytogenetic Analysis , Duodenal Neoplasms/diagnosis , Duodenal Neoplasms/genetics , Humans , Immunophenotyping , Intestinal Polyps/diagnosis , Intestinal Polyps/genetics , Lymphoma, Mantle-Cell/diagnosis , Lymphoma, Mantle-Cell/genetics , Male , Middle Aged , Neoplasm Invasiveness/pathology , Neoplasms, Second Primary/diagnosis , Neoplasms, Second Primary/genetics , Neoplasms, Second Primary/pathology , Stomach Neoplasms/diagnosis , Stomach Neoplasms/genetics , Trisomy
12.
Water Sci Technol ; 46(11-12): 419-24, 2002.
Article in English | MEDLINE | ID: mdl-12523788

ABSTRACT

We examine the validity of pulse count of snapping shrimps for sea environmental monitoring. Snapping shrimps, which make a peculiar pulse sound, are found everywhere in the world. Pulse count can be achieved merely by recording their sounds for a few minutes by using a hydrophone without special biological knowledge. From field surveys and laboratory experiments, we found that the pulse count depends on water temperature when sea environment is normal, and it falls due to the occurrence of oxygen-deficient water. The results show that this method can be a useful index of the effect of water pollution on benthic animals in fixed-point observation.


Subject(s)
Animal Communication , Decapoda , Environmental Monitoring/methods , Water Pollutants/adverse effects , Acoustics , Animals , Behavior, Animal , Oxygen , Temperature
13.
Ann N Y Acad Sci ; 936: 526-30, 2001.
Article in English | MEDLINE | ID: mdl-11460510

ABSTRACT

We found a novel genetic abnormality, heterozygous C-->T nucleotide substitution at position -1138 bp in the 5'-flanking region of the fibrinogen A alpha gene, in patients with hypofibrinogenemia. Luciferase reporter assay using the pGL3-basic vector and CHO cells indicates that the transcriptional activity of a vector incorporated with -1138T was reduced to one-third that of a vector incorporated with -1138C. These results suggest that the region adjacent to the -1138C bp of the 5'-flanking region of the fibrinogen A alpha gene is one of the most crucial sites for the transcription of the fibrinogen A alpha gene.


Subject(s)
Fibrinogen/genetics , Heterozygote , Point Mutation , Aged , Aged, 80 and over , Animals , CHO Cells , Cricetinae , Genes, Reporter , Humans , Luciferases/genetics , Male , Polymerase Chain Reaction
14.
Rev Assoc Med Bras (1992) ; 46(2): 106-12, 2000.
Article in Portuguese | MEDLINE | ID: mdl-11022350

ABSTRACT

BACKGROUND: Active chronic osteomyelitis or complicating osteomyelitis are difficult to be diagnosed by radiological imaging modalities, such as plain radiograph and CT. They frequently cause increased bone remodeling, leading to nonspecific uptake of Tc-99m-bone scan agents and gallium-67. New radiopharmaceuticals with greater infection avidity are being developed, including the nonspecific polyclonal immunoglobulin (IgG) labeled with technetium-99m. Tc-99m-IgG may be available as a ready to use kit, with no reported side effects, low patient absorbed radiation dose and low cost. MATERIAL AND METHODS: 23 bone segments with suspected active chronic osteomyelitis or violated bone osteomyelitis were studied by Tc-99m-IgG scintigraphy. All patients underwent standard three-phase bone scintigraphy using methylene diphosphonate (Tc-99m-MDP), gallium-67 scintigraphy and plain radiographs, compared with clinical evaluation and laboratory tests values. RESULTS: Infection was found in 8 sites. Sensitivity and specificity for Tc-99m-MDP, gallium-67 and Tc-99m-IgG scintigraphy were, respectively, 88 and 36%, 75 and 73%, 88 and 82%. CONCLUSION: Tc-99m-IgG may be usefull in the scintigraphic evaluation of osteomyelitis.


Subject(s)
Antibodies , Bacterial Infections/diagnostic imaging , Osteomyelitis/diagnostic imaging , Technetium , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Infections/metabolism , Bacterial Infections/physiopathology , Chronic Disease , Female , Humans , Male , Middle Aged , Osteomyelitis/metabolism , Osteomyelitis/physiopathology , Radionuclide Imaging , Sensitivity and Specificity
15.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 46(2): 106-12, abr.-jun. 2000. tab, ilus
Article in Portuguese | LILACS | ID: lil-268361

ABSTRACT

OBJETIVO: O diagnóstico de osteomielite crônica em atividade ou sobreposta a outras patologias é difícil, pois estas situações mascaram os achados radiológicos de infecção. A especificidade da cintilografia do esqueleto ou com gálio-67 também é reduzida pela influência da remodelação óssea na captação destes radiofármacos. Anticorpos policlonais marcados com tecnécio-99m (Tc-99m-IgG) apresentam captação independente do metabolismo ósseo, sendo um dos radiofármacos em investigação para avaliação mais específica de infecção. CASUÍSTICA E MÉTODO: Neste estudo comparou-se a cintilografia com Tc-99m-IgG, cintilografia óssea trifásica e cintilografia com gálio-67 no diagnóstico da osteomielite crônica em atividade em 23 segmentos ósseos; correlacionando-as com dados clínico-laboratoriais e radiológicos. RESULTADOS: Oito dos 23 segmentos foram classificados como infectados, 11 não infectados e quatro inconclusivos. A sensibilidade e especificidade encontradas para cintilografia óssea, com gálio-67 e com Tc-99m-IgG foram, respectivamente, 88 e 36 por cento, 75 e 73 por cento, 88 e 82 por cento. CONCLUSÃO: Os resultados sugerem que a Tc-99m-IgG possa ser utilizada no diagnóstico da osteomielite crônica em atividade.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Osteomyelitis , Bacterial Infections , Technetium , Antibodies , Osteomyelitis/physiopathology , Osteomyelitis/metabolism , Bacterial Infections/physiopathology , Bacterial Infections/metabolism , Aged, 80 and over , Chronic Disease , Sensitivity and Specificity
16.
J Hepatol ; 30(5): 807-18, 1999 May.
Article in English | MEDLINE | ID: mdl-10365806

ABSTRACT

BACKGROUND/AIMS: Sepsis and lipopolysaccharides (LPS) cause mild to severe hepatic dysfunction. In this study, Kupffer cell activation, involvement of TNFalpha and caspases downstream of the TNFalpha receptor were examined in hepatocyte apoptosis induced by LPS. METHODS: In in vivo experiments, male Sprague-Dawley rats were injected intravenously with LPS, and small amounts of the blood and liver were sampled to evaluate apoptosis. Kupffer cells were inactivated by pretreatment with gadolinium chloride for 2 days. In in vitro experiments, hepatocytes and Kupffer cells were separately isolated from rat livers using collagenase perfusion. RESULTS: LPS induced time-dependent and dose-dependent increases in the number of TUNEL-positive cells, which coincided with the apoptotic features of hepatocytes demonstrated by electron microscopy and DNA ladder. Activation of caspase-3-like proteases was observed with an increase in the number of apoptotic hepatocytes. Immunostaining with activated caspase-3-specific antibody showed that caspase-3 was activated only in the cytoplasm of TUNEL-positive hepatocytes. Inactivation of Kupffer cells by gadolinium chloride was concomitantly accompanied by the prevention of caspase-3 activation, hepatocyte apoptosis and liver injury induced by LPS. The co-culture system of hepatocytes and Kupffer cells, but neither cell culture system, individually, showed LPS-induced hepatocyte apoptosis. Kupffer cell-conditioned medium induced hepatocyte apoptosis, whereas addition of anti-TNFalpha antibody to Kupffer cell-conditioned medium did not. Additions of acetyl-DEVD-CHO, acetyl-YVAD-CHO, and acetyl-IETD-CHO to Kupffer cell-conditioned medium decreased the number of apoptotic hepatocytes. CONCLUSIONS: These results suggest that the activation of Kupffer cells, TNFalpha and caspases downstream of TNFR1 were involved in hepatocyte apoptosis induced by LPS.


Subject(s)
Apoptosis , Caspases/metabolism , Endotoxins/toxicity , Kupffer Cells/physiology , Lipopolysaccharides/toxicity , Liver/drug effects , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Bilirubin/blood , Caspase 3 , Cells, Cultured , Coculture Techniques , Culture Media, Conditioned , Cytoplasm/enzymology , Endotoxins/administration & dosage , Enzyme Activation , Gadolinium/pharmacology , In Situ Nick-End Labeling , Injections, Intravenous , Kupffer Cells/drug effects , Kupffer Cells/pathology , Lipopolysaccharides/administration & dosage , Liver/enzymology , Liver/pathology , Liver/ultrastructure , Male , Rats , Rats, Sprague-Dawley
17.
J Gastroenterol Hepatol ; 14(3): 236-40, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10197492

ABSTRACT

AIMS: Endoscopic variceal ligation (EVL) is a recently developed alternative to endoscopic injection sclerotherapy (EIS) for the treatment of oesophageal varices. Endoscopic variceal ligation and EIS were compared in an attempt to clarify the efficacy and safety of EVL for patients with cirrhosis due to hepatitis C. METHODS: Endoscopic variceal ligation was performed in 60 patients and EIS in 30. Varices were eradicated in all patients by EVL and 87% (26 out of 30) by EIS. RESULTS: There was no significant difference between EVL and EIS in relation to the incidence of bleeding and the 5 year survival rate after treatment. There were no severe complications except mild substernal pain after EVL, while pulmonary embolism occurred in one patient receiving EIS. CONCLUSIONS: Endoscopic variceal ligation is a safe and effective technique for eradicating oesophageal varices in patients with hepatitis C cirrhosis.


Subject(s)
Esophageal and Gastric Varices/therapy , Hemostasis, Endoscopic , Hepatitis C/complications , Liver Cirrhosis/virology , Polyethylene Glycols/therapeutic use , Sclerosing Solutions/therapeutic use , Esophageal and Gastric Varices/prevention & control , Female , Follow-Up Studies , Gastrointestinal Hemorrhage/epidemiology , Gastrointestinal Hemorrhage/prevention & control , Humans , Ligation , Male , Middle Aged , Polidocanol , Time Factors , Treatment Outcome
18.
J Biol Chem ; 273(51): 34272-7, 1998 Dec 18.
Article in English | MEDLINE | ID: mdl-9852091

ABSTRACT

Nitric oxide (NO) is implicated in apoptosis and has both cytotoxic and cytoprotective effects. Exogenous NO induced the death of PC12 and HeLa cells via a process showing features of both apoptosis and necrosis, with chromatin condensation, nuclear compaction, and mitochondrial swelling. Activation of caspases was not observed during NO-induced cell death. In addition, cell death was not inhibited by peptide caspase inhibitors or by expression of p35, a baculovirus-encoded caspase inhibitor, indicating that NO-induced cell death was independent of caspases. NO-induced cell death was enhanced by Bax expression in a caspase-independent manner and prevented by the anti-cell death protein Bcl-2. Although Bcl-2 has previously been shown to prevent cell death by inhibiting caspase activation, these results indicate that it can also prevent cell death via a caspase-independent mechanism.


Subject(s)
Apoptosis/physiology , Caspases/metabolism , Proto-Oncogene Proteins c-bcl-2/physiology , Adrenal Gland Neoplasms , Animals , Apoptosis/drug effects , Caspase 3 , Caspase Inhibitors , Enzyme Inhibitors/pharmacology , HeLa Cells , Humans , Kinetics , Mice , Necrosis , Nitric Oxide/physiology , Oligopeptides/pharmacology , PC12 Cells , Penicillamine/analogs & derivatives , Penicillamine/pharmacology , Pheochromocytoma , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/physiology , Proto-Oncogene Proteins c-bcl-2/genetics , Rats , Recombinant Proteins/metabolism , S-Nitroso-N-Acetylpenicillamine , Transfection , bcl-2-Associated X Protein
19.
Am J Physiol ; 275(1): H243-9, 1998 07.
Article in English | MEDLINE | ID: mdl-9688920

ABSTRACT

Hepatic tissue perfusion and O2 supply after ischemia are indispensable for recovery of cellular functions, but few studies have been performed regarding the recovery of tissue blood flow and O2 transport. After 5, 15, and 30 min of ischemia of rat livers, hepatic tissue perfusion, hepatic arterial and portal blood flow, plasma PO2, and O2 transport parameters were measured. Hepatic tissue blood flow and erythrocyte velocity in the sinusoids showed biphasic recoveries after temporal ischemia for 5, 15, and 30 min. The first peak in the flow appeared at 3-4 min after the initiation of tissue perfusion, and the second peak appeared at approximately 20 min, irrespective of the ischemic period. Hepatic blood flow during the initial increase contained relatively low O2-saturated blood compared with that in the second increase. Livers that had been subjected to a prior hepatic artery ligation only showed the first peak at approximately 4 min. The first increase in hepatic blood flow corresponded to the peak in the portal venous flow, and the second increase corresponded to that of the hepatic artery. These results suggested that hepatic microcirculation after temporary hepatic ischemia showed biphasic recoveries because of different restoration patterns of the portal vein and hepatic artery.


Subject(s)
Blood Flow Velocity , Ischemia/physiopathology , Liver Circulation/physiology , Liver/blood supply , Oxygen/blood , Animals , Erythrocytes/physiology , Hemoglobins/metabolism , Hepatic Artery/physiology , Hepatic Artery/physiopathology , Ischemia/blood , Laser-Doppler Flowmetry , Male , Oxyhemoglobins/metabolism , Portal System/physiology , Rats , Rats, Inbred Lew , Regional Blood Flow , Reperfusion , Time Factors
20.
Gan To Kagaku Ryoho ; 25(9): 1262-5, 1998 Jul.
Article in Japanese | MEDLINE | ID: mdl-9703803

ABSTRACT

Between 1990 and 1997, 227 patients with hepatocellular carcinoma were treated by intrahepatic arterial injection of a Lipiodol-Epirubicin-Mitomycin C emulsion followed by intermittent hepatic artery infusion of Epirubicin, Mitomycin C and 5-FU, employing an implantable subcutaneous infusion port. A catheter was inserted percutaneously into the hepatic artery using the Seldinger technique. Objective remission was induced in 80% of the evaluable patients as evidenced by a decrease in their AFP and PIVKA II levels. These remissions were also confirmed by liver sonogram and CT scan showing decreased tumor volume. Transcatheter oily chemoembolization combined with intermittent hepatic artery infusion chemotherapy seems to be an effective treatment for unresectable hepatocellular carcinoma both for palliation of symptoms as well as prolongation of survival with good quality of life.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic , Infusion Pumps, Implantable , Iodized Oil/administration & dosage , Liver Neoplasms/therapy , Drug Administration Schedule , Epirubicin/administration & dosage , Fluorouracil/administration & dosage , Hepatic Artery , Humans , Infusions, Intra-Arterial , Mitomycin/administration & dosage
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