Synthesis of acylated derivatives of chitosan oligosaccharide and evaluation of their potential antifungal agents on Fusarium oxysporum.

Chitosan oligosaccharide (COS) is an important carbohydrate-based biomaterial for synthesizing candidate drugs and biological agents. This study synthesized COS derivatives by grafting acyl chlorides of different alkyl chain lengths (C8, C10, and C12) onto COS molecules and further investigated their physicochemical properties and antimicrobial activity. The COS acylated derivatives were characterized using Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy, X-ray diffraction, and thermogravimetric analysis. COS acylated derivatives were successfully synthesized and possessed high solubility and thermal stability. As for the evaluation of antibacterial activity, COS acylated derivatives did not significantly inhibit Escherichia coli and Staphylococcus aureus, but they significantly inhibited Fusarium oxysporum, which was superior to that of COS. Transcriptomic analysis revealed that COS acylated derivatives exerted antifungal activity mainly by downregulating the expression of efflux pumps, disrupting cell wall integrity, and impeding normal cell metabolism. Our findings provided a fundamental theory for the development of environmentally friendly antifungal agents.

MEK homologue is involved in immune response by regulating antimicrobial peptides expression in Chinese mitten crab Eriocheir sinensis.

MEK activates the phosphorylation of downstream molecules involved in various immune responses. In this study, an MEK homologue gene in Chinese mitten crab Eriocheir sinensis (designated as EsMEK) was investigated. EsMEK mRNA was constitutively expressed in all tissues with higher expression in hepatopancreas, hemocytes, and gills. EsMEK protein was mainly localized in the cytoplasm. Lipopolysaccharide (LPS) and Aeromonas hydrophila challenge significantly increased the mRNA levels of EsMEK in hemocytes. In addition, the mRNA expression level of some antimicrobial peptides (AMPs), including EsWAP, EsDWD1, and EsALF decreased significantly due to the inhibition of EsMEK by specific dsRNA in LPS-challenged crabs. Downstream pathway analysis revealed that the phosphorylation of EsERK decreased prominently after EsMEK inhibition. These results suggested that EsMEK played an important role in regulating the expression of antimicrobial peptides in E. sinensis through MEK-ERK pathway.

PM2.5 Pollutant Concentrations in Greenspaces of Nanjing Are High but Can Be Lowered with Environmental Planning.

Small-scale greenspaces in high-density central urban districts serve as important outdoor activity spaces for the surrounding residents, especially the elderly. This study selects six small-scale, popular greenspaces with distinct characteristics that are jointly situated along the same main urban artery in a high-density central urban district. Field investigations and questionnaires are conducted and combined with statistical analyses, to explore the spatial-temporal distribution and influencing factors of PM2.5 concentrations in these greenspaces. The study finds that the air quality conditions in the sites are non-ideal, and this has potential negative impacts on the health of the elderly visitors. Moreover, the difference values of PM2.5 concentrations' spatial-temporal distributions are significantly affected by vehicle-related emissions, which have significant temporal characteristics. PM2.5 concentration is strongly correlated with percentage of green coverage (R = 0.82, p < 0.05), degree of airflow (R = -0.83, p < 0.05), humidity and comfort level (R = 0.54, p < 0.01 and R = -0.40, p < 0.01 respectively). Meanwhile, the sites' "sky view factor" is strongly correlated with degree of airflow (R = 0.82, p < 0.05), and the comfort level plays an indirect role in the process of PM2.5 affecting crowd activities. Based on this analysis, an optimal set of index ranges for greenspace elements which are correlated with the best reduction in PM2.5 concentrations is derived. As such, this research reveals the technical methods to best reduce their concentrations and provides a basis and reference for improving the quality of small-scale greenspaces in high-density urban districts for the benefit of healthy aging.

Complete genomic characterization of two European-genotype porcine reproductive and respiratory syndrome virus isolates in Fujian province of China.

Porcine reproductive and respiratory syndrome (PRRS) is considered one of the most devastating swine diseases worldwide, resulting in immense economic losses. PRRS virus (PRRSV) is divided into two major genotypes, European (type 1) and the North American (type 2). Type 1 PRRSV have recently emerged in Fujian province (South China), and this might have a significant impact on the Chinese pig industry. From 2013 to 2014, two type 1 PRRSV strains, named FJEU13 and FJQEU14, were isolated from piglets and sows with respiratory problems and reproductive disorders in Fujian province. The full genome length of the two isolates was 14,869-15,062 nucleotides (nt), excluding the poly(A) tail. These isolates shared 86.0-89.9% sequence identity with the prototypic strains Lelystad virus (LV) and 82.8-92% with Chinese type 1 PRRSV strains, but only 59.9-60.1% with the North American reference strain VR-2332. However, they were 82.9% identical to each other. Nonstructural protein 2 (Nsp2) and ORF3-ORF5 were the most variable regions when compared to other type 1 PRRSV strains. Nsp2 and ORF3 contained multiple discontinuous deletions and a 204-bp deletion in NSP2 in isolate FJQEU14, which has never been described in other Chinese type 1 PRRSV strains. All of these results might be useful for understanding the epidemic status of type 1 PRRSV in China.

Molecular characterization of two recombinant potato virus Y isolates from China.

Isolates of potato virus Y (PVY) have been divided into several strains. We determined the genomic sequences of PVY isolates AQ4 and FZ10 from tobacco in China. AQ4 and FZ10 had genome of 9700 and 9698 nucleotides, respectively. In phylogenetic analysis of complete genome sequences, AQ4 was clustered with strain N-Wi, and FZ10 with NTN. AQ4 had two recombination sites within the P1 and P3 genes, while FZ10 had three within the P1, P3 and NIa-Pro genes. When compared to typical NTN isolates, FZ10 lacked a recombination site within the CP gene and, thus, represents a novel recombination type of PVY.

Study of severe and rare complications of transarterial chemoembolization (TACE) for liver cancer.

OBJECTIVE: To study severe and rare complications of transarterial chemoembolization (TACE) for liver cancer. METHODS: Clinical records of severe and rare complications following TACE in 1348 cases of liver cancer from January 1997 to February 2004 were studied retrospectively. RESULTS: A total of 2012 TACE procedures were performed for 1348 patients. There were 3 cases of spontaneous rupture of liver cancer, 1 case of perforation of duodenum, 3 cases of liver abscess (1 of them was associated with sepsis), 1 case of pulmonary embolism, 1 case of spasm of the hepatic artery, 40 cases of hepatic artery occlusion, 3 cases of femoral nerve injury, 1 case of bilioma and 1 case of acute renal failure. CONCLUSION: Although the severe complications of TACE are rare, the procedure should be done cautiously including super selection of hepatic artery, slow infusion of lipiodol, careful postoperative observations and early detection and management of complications.

[Prognosis and risk factors for recurrence of small liver cancer after a single session of percutaneous radiofrequency ablation].

BACKGROUND & OBJECTIVE: As a new technique of local therapy for liver cancer, radiofrequency ablation (RFA) was widely used these years in China. This study was to evaluate the treatment efficacy of RFA on primary liver cancer (PLC), identify the risk factors of recurrence, and determine the indications of RFA for PLC. METHODS: Records of 94 primary small liver cancer patients underwent a single session of percutaneous RFA in Liver Cancer Institute/Zhongshan Hospital from Jan. 2001 to Dec. 2003 were reviewed retrospectively. Data analyses were performed using SPSS for windows Ver. 11.5 software. RESULTS: With a median follow-up of 16 months affer RFA treatment, the cumulative survival rate of 94 patients was 85.5% at 1 year, and 75.6% at 2 years. The cumulative recurrence-free survival rate was 31.3% at 1 year, and 10.4% at 2 years. The total recurrence rate was 66.0% (62/94). Log-rank test revealed that tumor with diameter of >3 cm (P< 0.05), proximity to intrahepatic vessels (P < 0.01), and subcapsular location (P< 0.05) were related to tumor recurrence,while gender, Child-pugh class, alpha fetoprotein (AFP) concentration, and combination therapy with percutaneous ethanol injection were not related to tumor recurrence. Cox regression analysis indicated that tumor proximity to intrahepatic vessels (95%CI, 2.102-7.899; P=0.000), and subcapsular location (95%CI, 1.672-6.289; P=0.001)were associated independently with recurrence after RFA treatment. Severe complications occurred in 2 cases (2.1%), including 1 case of bile duct hemorrhage, 1 case of sub-diaphragm effusion. No RFA related death and other severe complications occurred. CONCLUSIONS: RFA appears to be a safe treatment for liver cancer. Patients with tumor diameter of

Changed clinical aspects of primary liver cancer in China during the past 30 years.

BACKGROUND: Primary liver cancer (PLC) is one of the most frequently seen tumors in China. Thirty years ago, patients with PLC were often detected at relatively late stage, with a palpable mass or marked clinical symptoms and poor prognosis. In the past 30 years, the diagnosis and treatment of PLC have been greatly improved with better prognosis. METHODS: In order to study the changes of PLC during the 30 years, the clinical data of 3250 patients with PLC from 10 medical institutions of China were collected, analyzed, and compared with those of 3254 PLC patients before the 30 years. RESULTS: In the 3250 patients aged 1-80 years, with an average age of 49.1 years, the male to female ratio (2.3:1) was lower than that before the 30 years. 73.5% of the 3250 patients sought medical advice within 3 months after the onset of the disease in contrast to 63.8% before the 30 years. Compared with those patients before the 30 years the symptoms and signs were alleviated generally. The HBsAg positive rate was 81.0%, but the HCV-Ab positive rate was 13.2%. The AFP level in 75% of patients was elevated, but in the remaining 25% was normal. 1912 patients (58.8%) were confirmed pathologically. Among them 1755 patients (91.8%) had hepatocellular carcinoma. The overall resection rate was 46.3%. Those who had early, middle, late stage carcinoma accounted for 29.9%, 51.5%, and 18.6% respectively in contrast to 0.4%, 47.0%, and 52.6% reported before the 30 years. The 1-, 3-, 5-year survival rates of the patients were 66.1%, 39.7%, and 32.5% respectively, whereas 93.5%, 70.1%, and 59.1% for the early stage patients, and 65.3%, 30.5%, and 23.5% for the middle stage patients. The half and 1-year survival rates of the late stage patients were 52.5%, and 14.7%, respectively. CONCLUSION: Comparison with the clinical data before and after the 30 years show that PLC can be diagnosed early. More PLC patients tend to undergo resection while receiving a better conservative treatment, which ensures a prognosis.

Radiation therapy for the locoregional lymph node metastases from hepatocellular carcinoma, phase I clinical trial.

BACKGROUND/AIMS: The patients with lymph node metastasis from hepatocellular carcinoma may survive only a few months. These patients are not suitable for transcatheter arterial chemoembolization, percutaneous ethanol injection and surgical resection. External beam radiation therapy (EBRT) could provide a useful treatment, but only 4 hepatocellular carcinoma cases with abdominal lymph nodes involvement were treated with EBRT in the two reports over the last 10 years. In this paper, we report 29 hepatocellular carcinoma patients with abdominal lymph node metastasis who received EBRT over a period of 5 years. METHODOLOGY: Of 29 patients, 20 were pathologically confirmed to have hepatocellular carcinoma and 9 patients were clinically diagnosed to have hepatocellular carcinoma. All of the patients had proven abdominal lymph node metastasis by enhanced abdominal computer tomography scan due to clinical follow-up or abdominal symptoms. EBRT was not the initial treatment in all. The patients received locoregional lymph nodes irradiation. The tumor dose ranged from 30 to 60 Grays (Gy) in daily 2.0-Gy fractions (Fx), 5 times a week. RESULTS: It is of interest to note that an objective regression (complete response and partial response) rate was 100%. The clinical symptoms were relieved. The median survival time was 8 (4-28) months. The overall 1-year and 2-year survival rates were 43.5% and 10.5%, respectively. The median survival time consistently decreased as the lymph node involvement increase follows the natural flow of lymph. CONCLUSIONS: Lymph node metastasis from hepatocellular carcinoma is sensitive to EBRT, although EBRT is palliative in intent, it is useful in the treatment with 50 Gy/25 Fx for those patients.

Randomized controlled trial of screening for hepatocellular carcinoma.

PURPOSE: Screening for hepatocellular carcinoma (HCC) has been conducted for over 20 years, but there is no conclusive evidence that screening may reduce HCC mortality. The aim of this study was to assess the effect of screening on HCC mortality in people at increased risk. METHODS: This study included 18,816 people, aged 35-59 years with hepatitis B virus infection or a history of chronic hepatitis in urban Shanghai, China. Participants were randomly allocated to a screening (9,373) or control (9,443) group. Controls received no screening and continued to use health-care facilities. Screening group participants were invited to have an AFP test and ultrasonography examination every 6 months. Screening was stopped in December 1997; by that time screening group participants had been offered five to ten times. All participants were followed up until December 1998. The primary outcome measure was HCC mortality. RESULTS: The screened group completed 58.2 percent of the screening offered. When the screening group was compared to the control group, the number of HCC was 86 versus 67; subclinical HCC being 52 (60.5%) versus 0; small HCC 39 (45.3%) versus 0; resection achieved 40 (46.5%) versus 5 (7.5%); 1-, 3,-, and 5-year survival rate 65.9%, 52.6%, 46.4% versus 31.2%, 7.2%, 0, respectively. Thirty-two people died from HCC in the screened group versus 54 in the control group, and the HCC mortality rate was significantly lower in the screened group than in controls, being 83.2/100,000 and 131.5/100,000, respectively, with a mortality rate ratio of 0.63 (95%CI 0.41-0.98). CONCLUSIONS: Our finding indicated that biannual screening reduced HCC mortality by 37%.

[Changes of clinical aspect of primary liver cancer in China during the past 30 years--control study for 3,250 cases with primary liver cancer].

OBJECTIVE: To study the changes of the clinical aspects of primary liver cancer (PLC) during the past 30 years. METHODS: The clinical data of 3,250 patients with PLC, from 10 regions of China were collected, analyzed, and compared with the clinical data of 3254 PLC cases 30 years before. RESULTS: The 3,250 patients were aged 1- 80, with an average age of 49.1 years, younger than those 30 years before (43.7 years). The male to female ratio was 2.3:1, lower than that 30 years before (7.7:1). 73.5% of them sought medical advice within 3 months after the onset in comparison of 63.8% 30 years before. Compared with those 30 years before the symptoms and signs were alleviated in general. The HBsAg positive rate was 81.0%, the HCV-Ag positive rate was 13.2%, and the alpha-fetoprotein positive rate was 75%. 1912 cases underwent pathological examination of which 91.8% were diagnosed as with hepatocellular carcinoma. The overall resection rate was 46,3%. Those of early, median, and late stages accounted for 29.9%, 51.5%, and 18.6% respectively in comparison with the rates of 0.4%, 47.0%, and 52.6% 30 years before. The one-year survival rate, three-year survival rate, and five-year survival rate were 66.1%, 39.7%, and 32.5% respectively for the whole group, 93.5%, 70.1%, and 59.1% for the early stage patients, and 65.3%, 30.5%, and 23.5% respectively for the median stage patients. The half-year survival rate and one-year survival rate of the late stage patients were 52.5% and 14.7% respectively. Compared with the data 30 years before a lower percentages of the patients died of hepatic coma, hemorrhage of upper digestive tract and hemorrhage due to rupture of tumor, and a higher percentage of then died of asthenia universalis and other causes. CONCLUSION: In comparison with the situation 30 years ago, PLC can be diagnosed earlier. More patients undergo resection. The prognosis of PLC has been improved greatly.

Comparison between radioimmunotherapy and external beam radiation therapy for patients with hepatocellular carcinoma.

It has previously been observed in animal studies that, at equivalent doses, radioimmunotherapy (RIT) is 2.5 times more effective than multiple fractions of external beam radiation therapy (EBRT) in inhibiting tumour growth. In this study, we compared the use of RIT and EBRT in patients with hepatocellular carcinoma (HCC), treated during the past 10 years. Of 67 patients without extrahepatic involvement, 32 were treated with hepatic artery ligation combined with RIT (the RIT group) while 35 were treated with a combination of hepatic arterial chemo-embolisation and EBRT (the EBRT group). The patients in the RIT group received (131)I-Hepama-1 monoclonal antibody, which was infused through the hepatic artery catheter. The patients in the EBRT group received transcatheter arterial chemo-embolisation and limited-field EBRT using a linear accelerator. Parameters observed include tumour response, alpha-fetoprotein (AFP) level in serum, human anti-murine antibody (HAMA) assay, T lymphocyte subsets, survival rates, routine parameters, sequential resection rates and histopathological status of the resection specimens. The sequential resection rates were 53% (17/32) and 23% (8/35), and tumour response rates were 72% (23/32) and 86% (30/35) in the RIT and EBRT groups, respectively. The main side-effects in the RIT group were mild allergic reactions. The most common toxicity in the EBRT group was an increase in liver enzymes. The liver tissue in the target volume was injured by EBRT. The injured liver tissue revealed a low-attenuation area adjacent to the hepatic tumour within the target volume on follow-up computed tomography studies after EBRT. On pathological evaluation, the low-attenuation area revealed hyperaemia, distended hepatic sinusoids packed with erythrocytes and hepatic cell loss. The sequential resection specimens from both the RIT and the EBRT group showed residual cancer tissue located at the edge of the mass. The residual cancer cells presented as giant cells under microscopy. T lymphocyte subsets observed prior to treatment did not significantly change after RIT, but were significantly disturbed by EBRT. HAMA formation was the major reason for discontinuing RIT, the incidence being as high as 34% (11/32). Intrahepatic and pulmonary metastases occurred more frequently in the EBRT group (63%) than in the RIT group (22%). The 1-, 2-, 3- and 4-year survival rates were 50%, 41%, 34% and 31% in the RIT group, and 77%, 39%, 11% and 7% in the EBRT group, respectively. It is interesting that the serum AFP level showed a transient increase, the mechanism and importance of which are not known, but are discussed. Both RIT and EBRT are useful treatment modalities for unresectable HCC, serving to prolong survival. However, RIT is much less toxic than EBRT, the side-effects of which include radiation injury to the liver and disturbance of T lymphocyte subsets.

First example of an antibody-catalyzed aza Diels-Alder reaction.

Described herein is the synthesis of a hapten of biocyclo[2,2,2]octene 5 designed to mimic the exo transition-state of an aza Diels-Alder reaction. Immunization of rabbits with this hapten provided polyclonal antibodies, Aza-BSA-3, which were used to synthesize adduct 4b in the first reported antibody-catalyzed exo Diels-Alder reaction.

Enantioselective hydrolysis of naproxen ethyl ester catalyzed by monoclonal antibodies.

This report described that a hapten of racemic phosphonate 3 designed as the mimic of the transition state of hydrolysis of naproxen ethyl ester was successfully synthesized from easily available 2-acetyl-6-methoxy-naphthalene 5. Then BALB/C mice were immunized and one of the monoclonal catalytic antibodies, N116-27, which enantioselectively accelerated the hydrolysis of the R-(-)-naproxen ethyl ester was given. The Michaelis-Menton parameter for the catalyzed reaction was K(M)=6.67 mM and k(cat)/k(uncat)=5.8 x 10(4). This enantioselective result was explained by the fact that the R-isomer of rac-hapten was more immunogenic than the S-isomer.

Multimodality treatment of hepatocellular carcinoma.

By 1996, 2898 patients with pathologically proven hepatocellular carcinoma (HCC) had been treated at the Liver Cancer Institute of Shanghai Medical University. The 5 year survival in the entire series was 36.2%, being increased from 4.8% in 1958-70, 12.2% in 1971-83, to 50.5% in 1984-96 and 274 patients had survived more than 5 years. The increase in the survival rate could be attributed to the decreasing mean tumour diameter (11.7, 10.5 and 9.5 cm, respectively) and multimodality treatment. In addition to small HCC resection (5 year survival 64.9%, n = 735) and large HCC resection (5 year survival 37.4%, n = 1050), the following deserves to be mentioned. First, the 5 year survival of unresectable HCC treated by palliative surgery increased from 0% to 7.2% to 20.0%, which was related to the increase in use of multimodality treatment, particularly in those followed by second-stage resection. Second, cytoreduction and sequential resection is a new field with a significant potential in the treatment of localized unresectable HCC in a cirrhotic liver. Cytoreduction can be achieved by surgery, such as hepatic artery ligation, cannulation, cryosurgery and their combination, and followed by intrahepatic arterial chemoembolization, targeting therapy or regional radiotherapy. Ninety of 647 patients with unresectable HCC so treated had marked shrinkage of tumour and received second-stage resection; the 5 year survival was 71.4%. Third, non-surgical cytoreduction was mainly achieved by transcatheter arterial chemoembolization (TACE); for 70 patients with second-stage resection following TACE, the 5 year survival was 56.0%. Finally, re-resection of subclinical recurrence of tumour after curative HCC resection was performed in 155 patients; the 5 year survival calculated from the first resection was 50.9%, which played an important role in increasing the 5 year survival in the resection group (from 13.0% to 29.5% to 56.2%). It is concluded that multimodality treatment with combined and sequential use of different modalities and repeated use of some modalities is of substantial benefit for localized unresectable HCC.