1.Chemoprevention of gastric cancer: current status.
Harry Hua-Xiang XIA ; Benjiamin Chun-Yu WONG ; Shiu-Kum LAM
Chinese Medical Journal 2003;116(1):5-10
The development of gastric cancer is a multi-factor process. In addition to genetic factors, environmental factors including smoking, low gastric acidity, excessive intake of salt or salty food and low consumption of fresh fruits and vegetables all contribute to the development of gastric cancer. Of particular interest, epidemiological and experimental studies have demonstrated that Helicobacter pylori (H. pylori) infection is causally linked to gastric cancer. Most studies using micronutrient supplementation have failed to demonstrate any preventive effect against the development of gastric cancer. The use of non-steroidal anti-inflammatory drugs has been consistently observed to protect against the development of gastric cancer. Recently, eradication of H. pylori infection by a chemopreventative approach is being studied in a number of trials. Studies using precancerous lesions as an end point of the treatment have produced conflicting and mostly negative results. Trials using cancer as an end point are being cautiously carried out in high-risk populations, and will provide the definitive answer to this important question. In the end, vaccination may be proven to be the optimal strategy in human for the management of H. pylori infection and prevention of gastric cancer.
Anti-Inflammatory Agents, Non-Steroidal
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therapeutic use
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Anticarcinogenic Agents
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therapeutic use
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Dietary Supplements
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Helicobacter Infections
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complications
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drug therapy
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prevention & control
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Humans
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Stomach Neoplasms
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etiology
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prevention & control
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Vaccination
2.Effects of octreotide on expression of L-type voltage-operated calcium channels and on intracellular Ca2+ in activated hepatic stellate cells.
Hui-guo DING ; Bao-en WANG ; Ji-dong JIA ; Hua-xiang Harry XIA ; Chun-yu Benjamin WONG ; Chun-hui ZHAO ; Yan-lin XU
Chinese Medical Journal 2004;117(6):913-916
BACKGROUNDThe contractility of hepatic stellate cells (HSCs) may play an important role in the pathogenesis of cirrhosis with portal hypertension. The aim of this study was to research the effects of octreotide, an analogue of somatostatin, on intracellular Ca2+ and on the expression of L-type voltage-operated calcium channels (L-VOCCs) in activated HSCs, and to try to survey the use of octreotide in treatment and prevention of cirrhosis with portal hypertension complications.
METHODSHSC-T6, an activated HSCs line, was plated on small glass coverslips in 35-mm culture dishes at a density of 1 x 10(5)/ml, and incubated in DMEM media for 24 hours. After the cells were loaded with Fluo-3/AM, intracellular Ca2+ was measured by Laser Scanning Confocal Microscopy (LSCM). The dynamic changes in activated HSCs of intracellular Ca2+, stimulated by octreotide, endothelin-1, and KCl, respectively, were also determined by LSCM. Each experiment was repeated six times. L-VOCC expression in HSCs was estimated by immunocytochemistry.
RESULTSAfter octreotide stimulation, a significant decrease in the intracellular Ca2+ of activated HSCs was observed. However, octreotide did not inhibit the increases in intracellular Ca2+ after stimulation by KCl and endothelin-1. Moreover, octreotide did not significantly affect L-VOCC expression. These results suggest that neither L-VOCC nor endothelin-1 receptors in activated HSCs are inhibited by octreotide.
CONCLUSIONSOctreotide may decrease portal hypertension and intrahepatic vascular tension by inhibiting activated HSCs contractility through decreases in intracellular Ca2+. The somatostatin receptors in activated HSCs may be inhibited by octreotide.
Calcium ; analysis ; Calcium Channels, L-Type ; analysis ; Cells, Cultured ; Hepatocytes ; chemistry ; cytology ; drug effects ; Microscopy, Confocal ; Octreotide ; pharmacology
3.Circulation of influenza and other respiratory viruses during the COVID-19 pandemic in Australia and New Zealand, 2020–2021
Genevieve K O' ; Neill ; Janette Taylor ; Jen Kok ; Dominic E Dwyer ; Meik Dilcher ; Harry Hua ; Avram Levy ; David Smith ; Cara A Minney-Smith ; Timothy Wood ; Lauren Jelley ; Q Sue Huang ; Adrian Trenholme ; Gary McAuliffe ; Ian Barr ; Sheena G Sullivan
Western Pacific Surveillance and Response 2023;14(3):13-22
Objective: Circulation patterns of influenza and other respiratory viruses have been globally disrupted since the emergence of coronavirus disease (COVID-19) and the introduction of public health and social measures (PHSMs) aimed at reducing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission.
Methods: We reviewed respiratory virus laboratory data, Google mobility data and PHSMs in five geographically diverse regions in Australia and New Zealand. We also described respiratory virus activity from January 2017 to August 2021.
Results: We observed a change in the prevalence of circulating respiratory viruses following the emergence of SARS-CoV-2 in early 2020. Influenza activity levels were very low in all regions, lower than those recorded in 2017–2019, with less than 1% of laboratory samples testing positive for influenza virus. In contrast, rates of human rhinovirus infection were increased. Respiratory syncytial virus (RSV) activity was delayed; however, once it returned, most regions experienced activity levels well above those seen in 2017–2019. The timing of the resurgence in the circulation of both rhinovirus and RSV differed within and between the two countries.
Discussion: The findings of this study suggest that as domestic and international borders are opened up and other COVID-19 PHSMs are lifted, clinicians and public health professionals should be prepared for resurgences in influenza and other respiratory viruses. Recent patterns in RSV activity suggest that these resurgences in non-COVID-19 viruses have the potential to occur out of season and with increased impact.