[Evaluation of the efficacy of TIPS in 27 patients with hepatic sinus obstruction syndrome in the near and medium term].

Objective: intrahepatic portocaval shunt (TIPS) in the treatment of hepatic sinusoidal obstruction syndrome (HSOS). Methods: A retrospective analysis was performed on 27 patients with HSOS who were treated with TIPS in our center from July 2018 to July 2020. The changes of portal vein pressure (PVP), portal vein pressure gradient (PPG) and liver function were observed, so as to evaluate the efficacy. Paired t test was adopted to evaluate the quantitative parameters, while χ (2) test was used to analyze qualitative parameters, with P < 0.05 as statistical difference. Results: PVP decreased from (4.41 ± 0.18) kPa before shunt to (2.69 ± 0.11) kPa after shunt (t = 82.41, P < 0.001), PPG decreased from (3.23 ± 0.18) kPa before shunt to (1.46 ± 0.23) kPa after shunt (t = 32.41, P < 0.001). The liver function improved significantly after operation. After 24 months of follow-up, 3 patients developed stent restenosis and recanalized after balloon dilation. Three patients developed hepatic encephalopathy, which was improved after drug treatment. One patient underwent liver transplantation due to liver failure. Conclusion: TIPS is effective in the treatment of HSOS in the short and medium term, and can provide time for liver transplantation patients to wait for liver source.

[Study on the correlation between PPG and HVPG in patients with portal hypertension].

Objective: To explore the correlation between portal vein pressure gradient (PPG) and hepatic vein pressure gradient (HVPG) in patients with portal hypertension (PHT). Methods: 752 cases with portal hypertension (PHT) who underwent transjugular intrahepatic portosystemic shunt (TIPS) and met the enrollment criteria between January 2016 to December 2019 were analyzed for hepatic vein, inferior vena cava and portal vein pressure. Paired t-test was used for analysis. Pearson correlation test was used to estimate correlation coefficient and coefficient of determination. P<0.05 were considered statistically significant. Results: Wedged hepatic vein pressure (WHVP), portal vein pressure (PVP), correlation coefficient, and coefficient of determination were 27.98±8.95 mmHg, 33.85±7.33 mmHg, 0.329 (P<0.001), and 0.108, respectively. HVPG, PPG,correlation coefficient, and coefficient of determination were 16.84±7.97 mmHg, 25.11±6.95 mmHg (P<0.001), 0.145, and 0.021 (P<0.001), respectively. The difference between HVPG and PPG was greater than 5 mmHg in 524 cases, accounting for 69.7%. The difference between HVPG and PPG was within 5 mmHg or basically equal in 228 cases, accounting for 30.3%. The correlation coefficient between free hepatic venous pressure (FHVP) and inferior vena cava pressure (IVCP) was 0.568 (P<0.001), and the coefficient of determination was 0.323. According to the presence or absence of hepatic venous collaterals after balloon occluded hepatic angiography, they were divided into two groups: 157 (20.9%) cases in the group with hepatic venous collaterals, and 595 (79.1%) cases in the group without hepatic venous collaterals. The parameters of the two groups were compared: WHVP (15.73±3.63) mmHg vs. (31.22±6.90) mmHg, P<0.001; PVP (31.69±8.70) mmHg vs. (34.42±6.81) mmHg, P<0.001; HVPG (7.18±4.40) mmHg vs. (19.40±6.62) mmHg, P<0.001; PPG (24.24±8.11) mmHg vs. (25.34±6.60) mmHg, P<0.001; free hepatic venous pressure (FHVP) (8.58±3.37) mmHg vs. (11.82±5.07) mmHg , P<0.001; inferior vena cava pressure (IVCP) (7.45±3.29) mmHg vs. (9.09±4.14) mmHg, P<0.001. Conclusion: The overall correlation is poor between HVPG and PPG. HVPG of most patients is not an accurate representation of PPG, and the former is lower than the latter. Hepatic venous collateral formation is one of the important reasons for the serious underestimation of HVPG values.

[Analysis of 53 cases of transjugular liver biopsy].

Objective: To investigate the practicability and safety of transjugular liver biopsy (TJLB). Methods: Data of 53 cases with transjugular liver biopsy from June 2015 to June 2020 were collected. LABS-100 was used in all patients who underwent transjugular liver biopsy. Among them, 45 cases and eight were biopsied via hepatic vein and intrahepatic segment of the inferior vena cava. The surgical indications, related complications, and postoperative pathological diagnosis were analyzed and summarized. Results: TJLB was successful in all patients, with an average of 2.8 punctures per case. Satisfactory liver tissue and histopathological diagnosis was obtained in all patients. Two cases developed a cervical hematoma that was improved spontaneously, and one patient developed an intrahepatic hematoma that was improved after conservative treatment. Conclusion: TJLB is a practical and safe method for patients with contraindications to percutaneous liver biopsy.

[The study of a key molecule Caspase-1 of inflammasome in hepatitis B virus-related diseases].

Objective: To investigate the expression and role of asparte-specific cysteine protease (Caspase)-1, inflammasomes key molecule, in hepatitis B virus (HBV)-related diseases. Methods: HBV-related liver disease patients' serum (438 cases) and liver tissue (82 cases) samples were collected from Beijing You'an Hospital affiliated with Capital Medical University. The mRNA expression level of caspase-1 in liver tissue was detected by real-time fluorescence quantitative PCR (qRT-PCR). The protein expression level of Caspase-1 in liver tissue was detected by the immunofluorescence method. The activity of Caspase-1 was detected using the Caspase-1 colorimetric assay kit. The level of Caspase-1 in the serum was detected by an ELISA kit. Results: The results of qRT-PCR showed that the mRNA level of Caspase-1 was downregulated in patients with chronic hepatitis B (CHB), cirrhosis (LC), and hepatocellular carcinoma (HCC), while up-regulated in patients with acute-on-chronic liver failure (ACLF) (P＜0.01) compared with normal subjects. Immunofluorescence assays showed that Caspase-1 protein levels were elevated in ACLF patients, decreased in HCC and LC patients, and slightly elevated in CHB patients. The activity of Caspase-1 was slightly higher in liver tissue from CHB, LC, and HCC patients than in the normal control group, and there was no statistically significant difference between the groups. Additionally, compared with the control group, Caspase-1 activity was significantly reduced in the ACLF group (P＜0.01). Serum Caspase-1 levels were significantly lower in patients with CHB, ACLF, LC, and HCC than in normal subjects, and serum Caspase-1 levels were lowest in patients with ACLF (P＜0.001). Conclusion: Caspase-1, a key molecule of inflammasomes, plays an important role in HBV-related diseases and has significant differences, showing distinct features for ACLF than other HBV-related diseases.

[The role of circulating tumor DNA in the diagnosis and prognosis of hepatocellular carcinoma].

Hepatocellular carcinoma (HCC) is one of the common malignant tumors. However, the detection of biomarkers can't meet the clinical needs for the diagnosis and prognosis of HCC now. Circulating tumor DNA (ctDNA) is a highly tumor-specific DNA molecule that exists in the blood circulation. It is part of Circulating cell free DNA (cfDNA) and originates from the primary tumor or metastasis of cancer patients. Now, with the developing of next-generation sequencing technology and a full understanding of HCC genetics or epigenetic changes, we can analyze ctDNA mutations and methylation more comprehensively. Through continuous exploration of ctDNA mutations and methylation and continuous innovation of detection methods, HCC diagnosis and prognosis can be greatly improved in terms of specificity and sensitivity.

[Noninvasive assessment of the risk of esophageal variceal bleeding from noncirrhotic portal hypertension].

Objective: To verify Baveno VI criteria, Expanded-Baveno VI criteria, liver stiffness×spleen diameter-to-platelet ratio risk score (LSPS), and platelet count/spleen diameter ratio (PSR) in evaluating the severity value of esophageal varices (EV) in patients with non-cirrhotic portal hypertension (NCPH). Methods: 111 cases of NCPH and 204 cases of hepatitis B cirrhosis who met the diagnostic criteria were included in the study. NCPH included 70 cases of idiopathic non-cirrhotic portal hypertension (INCPH) and 41 cases of nontumoral portal vein thrombosis (PVT). According to the severity of EV on endoscopy, they were divided into the low-bleeding-risk group (no/mild EV) and the high-bleeding-risk group (moderate/severe EV). The diagnostic value of Baveno VI and Expanded-Baveno VI criteria was verified to evaluate the value of LSPS and PSR for EV bleeding risk severity in NCPH patients. The t-test or Mann-Whitney U test was used to compare the measurement data between groups. Comparisons between counting data groups were performed using either the χ2 test or the Fisher exact probability method. Results: Considering endoscopy was the gold standard for diagnosis, the missed diagnosis rates of low/high bleeding risk EVs in INCPH/PVT patients with Baveno VI and Expanded-Baveno VI criteria were 50.0%/30.0% and 53.8%/50.0%, respectively. There were no statistically significant differences in platelet count (PLT), spleen diameter, liver stiffness (LSM), LSPS, and PSR between low-bleeding-risk and high-bleeding-risk groups in INCPH patients, and the area under the receiver operating characteristic curve (AUC) of LSPS and PSR was 0.564 and 0.592, respectively (P=0.372 and 0.202, respectively). There were statistically significant differences in PLT, spleen diameter, LSPS, and PSR between the low and high-bleeding risk groups in PVT patients, and the AUCs of LSPS and PSR were 0.796 and 0.833 (P=0.003 and 0.001, respectively). In patients with hepatitis B cirrhosis, the Baveno VI and Expanded-Baveno VI criteria were used to verify the low bleeding risk EV, and the missed diagnosis rates were 0 and 5.4%, respectively. There were statistically significant differences in PLT, spleen diameter, LSM, LSPS and PSR between the low-bleeding-risk and high-bleeding-risk groups (P<0.001). LSPS and PSR AUC were 0.867 and 0.789, respectively (P<0.05). Conclusion: Baveno VI and Expanded-Baveno VI criteria have a high missed diagnosis rate for EVs with low bleeding risk in patients with INPCH and PVT, while LSPS and PSR have certain value in evaluating EV bleeding risk in PVT patients, which requires further clinical research.

Molecular cloning and characterization of CD63 in common carp infected with koi herpesvirus.

CD63 is a member of the four-transmembrane-domain protein superfamily and is the first characterized tetraspanin protein. In the present study, we cloned the common carp (Cyprinus Carpio) CD63 (ccCD63) sequence and found that the ccCD63 ORF contained 711 bp and encoded a protein of 236 amino acids. Homology analysis revealed that the complete ccCD63 sequence had 84.08% amino acid similarity to CD63 of Sinocyclocheilus anshuiensis. Subcellular localization analysis revealed that ccCD63 was localized in the cytoplasm. Quantitative real-time PCR (qRT-PCR) analysis indicated that ccCD63 was expressed in the gill, intestine, liver, spleen, brain and kidney, with higher expression in spleen and brain tissues than in the other examined tissues. After koi herpesvirus (KHV) infection, these tissues exhibited various expression levels of ccCD63. The expression level was the lowest in the liver and highest in the brain; the expression level in the brain was 8.7-fold higher than that in the liver. Furthermore, knockdown of ccCD63 promoted KHV infection. Moreover, ccCD63 was correlated with the regulation of RIG-I/MAVS/TRAF3/TBK1/IRF3 and may be involved in the antiviral response through the RIG-I viral recognition signalling pathway in a TRAF3/TBK1-dependent manner. Taken together, our results suggested that ccCD63 upregulated the interaction of KHV with the host immune system and suppressed the dissemination of KHV.

[Molluscicidal effect of immersion with 50% wettable powder of niclosamide ethanolamine salt against Oncomelania hupensis on the soil surface and inside the soil layer in winter].

OBJECTIVE: To evaluate the molluscicidal effect of 50% wettable powder of niclosamide ethanolamine salt (WPNES) against Oncomelania hupensis on the soil surface and inside the soil layer by immersion method in winter. METHODS: O. hupensis snails were placed on the soil surface and 2, 5 cm and 10 cm under the soil layer outdoors in winter, and then immersed in 50% WPNES at concentrations of 1 mg/L and 2 mg/L for 1, 3 d and 7 d, while dechlorinated water served as controls. Snail mortality was observed following immersion with 50% WPNES on the soil surface and inside the soil layer. RESULTS: Following immersion with 50% WPNES at concentrations of 2 mg/L and 1 mg/L outdoors in winter, the 3-day corrected snail mortality rates were 98.0% and 76.0% on the soil surface, and the 7-day corrected snail mortality rate was both 100.0%. Following immersion with 50% WPNES at concentrations of 2 mg/L and 1 mg/L outdoors in winter, the 7-day corrected snail mortality rates were 95.5% and 85.6% 2 cm below the soil layer, 66.0% and 6.4% 5 cm below the soil layer. However, the 7-day snail mortality rate swere comparable between the 50% WPNES treatment group (at 2 mg/L and 1 mg/L) and controls 10 cm below the soil layer (both P > 0.05). CONCLUSIONS: Immersion of 50% WPNES at a concentration of 2 mg/L for 7 days presents a high molluscicidal efficacy against O. hupensis on the soil surface and 5 cm within the soil layers in winter.

[Three dimensional finite element model of a modified posterior cervical single open-door laminoplasty].

Objective: To build a three-dimensional finite element models of a modified posterior cervical single open-door laminoplasty with short-segmental lateral mass screws fusion. Methods: The C(2)-C(7) segmental data were obtained from computed tomography (CT) scans of a male patient with cervical spondylotic myelopathy and spinal stenosis.Three-dimensional finite element models of a modified cervical single open-door laminoplasty (before and after surgery) were constructed by the combination of software package MIMICS, Geomagic and ABAQUS.The models were composed of bony vertebrae, articulating facets, intervertebral disc and associated ligaments.The loads of moments 1.5Nm at different directions (flexion, extension, lateral bending and axial rotation)were applied at preoperative model to calculate intersegmental ranges of motion.The results were compared with the previous studies to verify the validation of the models. Results: Three-dimensional finite element models of the modified cervical single open- door laminoplasty had 102258 elements (preoperative model) and 161 892 elements (postoperative model) respectively, including C(2-7) six bony vertebraes, C(2-3)-C(6-7) five intervertebral disc, main ligaments and lateral mass screws.The intersegmental responses at the preoperative model under the loads of moments 1.5 Nm at different directions were similar to the previous published data. Conclusion: Three-dimensional finite element models of the modified cervical single open- door laminoplasty were successfully established and had a good biological fidelity, which can be used for further study.

Bioactive Natural Protein-Hydroxyapatite Nanocarriers for Optimizing Osteogenic Differentiation of Mesenchymal Stem Cells.

Improving the controlled release of bioactive growth factors to regulate cell behavior and tissue regeneration remains a need in tissue engineering and regenerative medicine. Inorganic and polymeric nanoparticles have been extensively fabricated as bioactive biomaterials with enhanced biocompatibility and effective carriers of therapeutic agents, however, challenges remain such as the achievement of high loading capacity and sustained release, and the bioactivity preservation of growth factors. Here, a multilayered, silk coated hydroxyapatite (HA) nanocarrier with drug loading-release capacity superior to pure silk or HA nanoparticles was developed. Bone morphogenetic protein-2 (BMP-2) was bound to the silk coatings with a high binding efficiency of 99.6%, significantly higher than that in silk or the HA nanoparticles alone. The release of BMP-2 was sustained in vitro over a period of 21 days without burst release. Compared with BMP-2 loaded silk or HA particles, bone mesenchymal stem cells (BMSCs) showed improved proliferation and osteogenesis when cultured with the BMP-2 loaded composite nanocarriers. Therefore, these silk-HA composite nanoparticles present a useful approach to designing bioactive nanocarrier systems with enhanced functions for bone tissue regeneration needs.

Circulating Tumor Cell Isolation and Analysis.

Isolation and analysis of cancer cells from body fluids have significant implications in diagnosis and therapeutic treatment of cancers. Circulating tumor cells (CTCs) are cancer cells circulating in the peripheral blood or spreading iatrogenically into blood vessels, which is an early step in the cascade of events leading to cancer metastasis. Therefore, CTCs can be used for diagnosing for therapeutic treatment, prognosing a given anticancer intervention, and estimating the risk of metastatic relapse. However, isolation of CTCs is a significant technological challenge due to their rarity and low recovery rate using traditional purification techniques. Recently microfluidic devices represent a promising platform for isolating cancer cells with high efficiency in processing complex cellular fluids, with simplicity, sensitivity, and throughput. This review summarizes recent methods of CTC isolation and analysis, as well as their applications in clinical studies.

The role of contrast-enhanced ultrasound in planning treatment protocols for hepatocellular carcinoma before radiofrequency ablation.

AIM: To evaluate the clinical value of contrast-enhanced ultrasound (CEUS) for patients with hepatocellular carcinoma (HCC) in identifying the tumour number, ablation range and feeding vessels before ultrasound-guided radiofrequency ablation (RFA), and to compare the efficacy of RFA after CEUS with the efficacy of RFA after non-enhanced ultrasonography (US) without contrast medium administration. MATERIALS AND METHODS: From 2002 to 2005, 81 patients with 110 HCCs underwent CEUS with SonoVue before RFA treatment (group A). Eighty six patients with 112 HCCs who underwent US without contrast enhancement before RFA served as the control group (group B). The average diameters of the lesions in group A and group B were 3.6+/-1.1cm and 3.5+/-1.1cm, respectively. There were no significant differences in clinical data between the two groups. Regular follow-up after treatment was performed using contrast-enhanced computed tomography (CECT). After treatment, complete necrosis was defined as the absence of viable tissue in treated tumours at the 1-year follow-up CECT. RESULTS: Using CEUS an additional seven small lesions (< or =2.0 cm) were found compared with those found using CECT and conventional US. CEUS showed that 56.4% of lesions (62/110 tumours) were larger in size and 49.1% (54/110 tumours) became more irregular in shape during the arterial phase than on conventional US. Feeding vessels were detected using CEUS in 52 (91.2%) of 57 lesions that were larger than 3.5 cm. The follow-up period was at least 1 year for each case. The complete tumour necrosis rate in group A was significantly higher than that in group B (92.2% versus 83.0%; p=0.036). CONCLUSION: CEUS can be used to more accurately define the size and contour of lesions, and to detect additional small or satellite lesions and the feeding vessel of HCC tumours. CEUS provided important information for designing the ablation protocol, and might improve the efficacy of RFA.

Application of disposable plastic microfluidic device arrays with customized chemistries to multiplexed biochemical assays.

Plastic microfluidic array platforms and synergistic multiplexed assay chemistries are under development for a variety of applications, including assays of gene expression, proteomics, genotyping, DNA sequencing and fragment analysis, sample preparation and high-throughput pharmaceutical discovery. The low production costs of plastic substrates makes possible economical single-use device arrays, eliminating cleaning and sample-to-sample carryover contamination. Hundreds of microchannels and reservoirs are readily included on a single microtitre-plate-size substrate, enabling the manufacture of highly parallel fluidic array systems to increase throughput and speed.

Dynamic DNA hybridization on a chip using paramagnetic beads.

Dynamic DNA hybridization is presented as an approach to perform gene expression analysis. The method is advantageous because of its dynamic supplies of both DNA samples and probes. The approach was demonstrated on a microfluidic platform by incorporating paramagnetic beads as a transportable solid support. A glass chip was fabricated to allow simultaneous interrogation of eight DNA target samples by DNA probes. DNA targets were immobilized on beads via streptavidin-biotin conjugation or base pairing between oligonucleotide residues. The DNA/bead complex was introduced into the device in which hybridization took place with a complementary probe. The hybridized probe was then removed by heat denaturation to allow the DNA sample to be interrogated again by another probe with a different sequence of interest. A pneumatic pumping apparatus was constructed to transport DNA probes and other reagents into the microfluidic device while hydrostatic pumping was used for the introduction of paramagnetic beads with samples. After investigating three types of paramagnetic beads, we found Dynabeads Oligo(dT)25 best suited this application. Targets on the beads could be sequentially interrogated by probes for 12 times, and the hybridization signal was maintained within experimental variation. Demonstration of specific hybridization reactions in an array format was achieved using four synthesized DNA targets in duplicate and five probes in sequence, indicating the potential application of this approach to gene expression analysis.

Effects of injector geometry and sample matrix on injection and sample loading in integrated capillary electrophoresis devices.

The double-T injector design employed in many microchip capillary electrophoresis devices allows for the formation of very small (50-500 pL) sample plugs for subsequent analysis on-chip. In this study, we show that sample plugs formed at the channel junction can be geometrically defined. The channel width and injector symmetry prove to be of great importance to good performance. A unique pushback of solvent into the side channels can be induced when the side channels have a very low resistance to flow, and this helps to better define the injected sample plug. Samples and running buffers of differing ionic strength (e.g., 10 mM KCl buffer and 20 mM KCl sample) can yield widely variable results in terms of plug shape and amount injected (variations of 1.5 to 10x). Applying bias voltages to all the intersecting channels aids in controlling the plug shape. However, when the ionic strengths of buffer and sample are not matched, the actual amount injected (up to 10x variations) can be inconsistent with the appearance of the plug formed in the injector (up to only 30 % variations). Operating at constant pH and ionic strength produced the most consistent results. This report examines the effects of altering the injector geometry and solution ionic strengths, and presents the results of using bias voltages to control plug formation. The observed results should provide a benchmark for modeling of the fluid dynamics in channel intersections.

[Review on transforming growth factor beta and repair of tissue injury].

OBJECTIVE: To review the progress of the relation between transforming growth factor beta (TGF-beta) and repair of tissue injury. METHODS: The recent articles about TGF-beta and tissue reconstruction were extensively reviewed. The gene identification, production, activation of TGF-beta and its role in the repair course of tissue injury were investigated. RESULTS: TGF-beta belongs to a family of multifunctional polypeptides, its gene structure is highly conservative. Many animal models about TGF-beta and tissue injury have been established. The research mainly focuses on the classification, distribution of TGF-beta receptors and their signal pathway. CONCLUSION: TGF-beta plays an important roles in the regulation of repair of tissue injury.

Microglial NO induces delayed neuronal death following acute injury in the striatum.

We have established a novel injury model in the central nervous system by a stereotaxic injection of ethanol into rat striatum to induce necrosis. With this model, we clarify a function of inducible nitric oxide synthase (iNOS) in a healing mechanism around a necrotic lesion. A semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) revealed that the iNOS mRNA arose at 6 h, peaked at 24 h, and declined to a lower level 48 h after an intrastriatal 5-microL ethanol injection. From in situ hybridization, this iNOS mRNA was expressed in the area surrounding the injury. By immunohistochemistry, mononuclear cells at this boundary area of necrosis were stained with anti-iNOS antibody on the first day after the injury. These cells turned out to be reactive microglia from the positive staining of GSA-I-B4, ED-1 and OX-42. Haematoxylin-eosin (HE) staining showed that neurons in this boundary area gradually disappear up to 5 days after the injury with an increment of microglial cells, and this area became cavernous. Nuclei of neurons in this area were stained positive by the terminal deoxynucleotidyl-transferase-mediated dUTP-biotin nick end-labelling (TUNEL) assay on the first day after the injury. These TUNEL-positive neurons gradually disappeared toward the third day, while microglial cells increased. L-Ng-nitro-arginine methylester (L-NAME), a competitive NOS inhibitor, administration diminished the elimination of neurons by microglia in this boundary area surrounding necrosis. Microglial NO may act as a neurotoxic agent to eliminate damaged neurons near the necrosis in the form of delayed neuronal death, and may reintegrate the neuronal circuits with functionally intact neurons.

In vitro and in vivo expression of inducible nitric oxide synthase during experimental endotoxemia: involvement of other cytokines.

In this study, we investigated the expression of genes for inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-alpha), interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6) of Kupffer cells in the presence of lipopolysaccharide (LPS), and the tissue expression of iNOS in a rat liver after LPS injection at various time intervals. The effects of L-NG-nitroarginine-methyl-esther HCI (L-NAME), a NO inhibitor, also were examined. The mRNA transcripts of TNF-alpha, IL-1 beta, and IL-6 were rapidly detected no more than at 1 h after LPS stimulation, whereas the iNOS transcript was detectable from 3 h after LPS stimulation and maximally increased at 12 h. This fact suggested that these early induced cytokines were related to expression of iNOS. Using an anti-iNOS antiserum raised against recombinant iNOS protein, immunohistochemical analysis was made to reveal kinetics of NO producing cells. The cells immunoreactive for iNOS appeared at 6 h post-LPS injection in the sinusoids of the liver. By structural and immunohistochemical studies, almost all iNOS positive cells were identified as Kupffer cells and endothelial cells. The number of cells immunoreactive for iNOS increased until 12 h post-LPS injection. At 24 h after LPS injection, iNOS positive cells were restricted to the foci of spotty necrosis. Hepatic injury measured by released enzymes was increased by pretreatment of L-NAME before LPS injection.

Nitric oxide as an inflammatory mediator of radiation pneumonitis in rats.

Radiation pneumonitis is a major complication of radiation therapy. To elucidate the mechanisms of radiation-induced pneumonitis, we studied nitric oxide (NO) produced from lung tissues using a model of unilaterally irradiated rats. Our results demonstrated that alveolar macrophages (AM) produced NO after irradiation, and the expression of inducible NO synthase (NOS) in both AM and alveolar epithelial cells was increased. Furthermore, the progression of radiation pneumonitis was reduced with the in vivo treatment of the NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME). The effect of L-NAME was further confirmed by the inhibition of mRNA expression for procollagen-alpha1 type III of the lung. With these results, NO produced from AM and alveolar epithelial cells after irradiation may be an important mediator in the progression of radiation pneumonitis.