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1.
Hum Mol Genet ; 31(16): 2779-2795, 2022 08 23.
Article in English | MEDLINE | ID: mdl-35348668

ABSTRACT

Hereditary spastic paraplegias (HSPs) comprise a large group of inherited neurologic disorders affecting the longest corticospinal axons (SPG1-86 plus others), with shared manifestations of lower extremity spasticity and gait impairment. Common autosomal dominant HSPs are caused by mutations in genes encoding the microtubule-severing ATPase spastin (SPAST; SPG4), the membrane-bound GTPase atlastin-1 (ATL1; SPG3A) and the reticulon-like, microtubule-binding protein REEP1 (REEP1; SPG31). These proteins bind one another and function in shaping the tubular endoplasmic reticulum (ER) network. Typically, mouse models of HSPs have mild, later onset phenotypes, possibly reflecting far shorter lengths of their corticospinal axons relative to humans. Here, we have generated a robust, double mutant mouse model of HSP in which atlastin-1 is genetically modified with a K80A knock-in (KI) missense change that abolishes its GTPase activity, whereas its binding partner Reep1 is knocked out. Atl1KI/KI/Reep1-/- mice exhibit early onset and rapidly progressive declines in several motor function tests. Also, ER in mutant corticospinal axons dramatically expands transversely and periodically in a mutation dosage-dependent manner to create a ladder-like appearance, on the basis of reconstructions of focused ion beam-scanning electron microscopy datasets using machine learning-based auto-segmentation. In lockstep with changes in ER morphology, axonal mitochondria are fragmented and proportions of hypophosphorylated neurofilament H and M subunits are dramatically increased in Atl1KI/KI/Reep1-/- spinal cord. Co-occurrence of these findings links ER morphology changes to alterations in mitochondrial morphology and cytoskeletal organization. Atl1KI/KI/Reep1-/- mice represent an early onset rodent HSP model with robust behavioral and cellular readouts for testing novel therapies.


Subject(s)
Disease Models, Animal , Membrane Proteins , Membrane Transport Proteins , Spastic Paraplegia, Hereditary , Animals , Axons/metabolism , Endoplasmic Reticulum/genetics , Endoplasmic Reticulum/metabolism , GTP Phosphohydrolases/genetics , Humans , Membrane Proteins/genetics , Membrane Transport Proteins/genetics , Mice , Mice, Knockout , Mutation , Spastic Paraplegia, Hereditary/genetics , Spastin/genetics
2.
Hepatology ; 59(6): 2207-15, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24425422

ABSTRACT

UNLABELLED: Limited data exist regarding metabolic risk factors for deaths from hepatocellular carcinoma (HCC) in aging individuals. We investigated the association between diabetes, dyslipidemia, and HCC mortality in those aged 40 years or more (middle-aged and elderly). In this prospective cohort study based on nationwide health screening units, we consecutively followed middle-aged and elderly participants who had no chronic hepatitis B or C virus infection and received health screening from January 1 1998 to December 31 2008. There were 235 deaths from HCC among 50,080 individuals, ascertained by validated death certificates and the national death registry. Diabetes (adjusted hazard ratio [HR], 3.38; 95% confidence interval [CI], 2.35 to 4.86) was positively associated with deaths from HCC. However, hypertriglyceridemia (HR, 0.38; 95% CI, 0.26 to 0.55) and hypercholesterolemia (HR, 0.50; 95% CI, 0.37 to 0.67) were inversely associated with HCC mortality. The above significant associations remained in the lag time analyses, applied to check for reverse causation. Metabolic syndrome, as defined by the American Heart Association / National Heart Lung Blood Institute criteria (HR, 0.63; 95% CI, 0.46 to 0.86) or by the International Diabetes Federation criteria (HR, 0.62; 95% CI, 0.43 to 0.89), was inversely associated with deaths from HCC, especially in men. CONCLUSION: Middle-aged and elderly individuals, once having diabetes, deserve HCC surveillance to reduce HCC mortality. More research is needed to elucidate why having baseline dyslipidemia relates to lower future HCC mortality.


Subject(s)
Carcinoma, Hepatocellular/mortality , Diabetes Complications/mortality , Dyslipidemias/epidemiology , Liver Neoplasms/mortality , Adult , Aged , Carcinoma, Hepatocellular/therapy , Diabetes Complications/therapy , Dyslipidemias/therapy , Female , Humans , Liver Neoplasms/therapy , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Risk Factors , Taiwan/epidemiology
3.
Helicobacter ; 20(3): 184-91, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25582223

ABSTRACT

BACKGROUND: Helicobacter pylori infection and metabolic syndrome have been reported to be positively associated. However, only a few studies have focused on this issue, and H. pylori serum antigen was used to diagnose infection in most of them. We aimed to investigate the association between metabolic syndrome factors and H. pylori infection, as diagnosed via a (13)C-urea breath test. MATERIALS AND METHODS: This cross-sectional study consisted of 3578 subjects (18-64 years old) enrolled from one health management center between 2008 and 2013. H. pylori infection was defined as a positive urea breath test. The risk of metabolic syndrome from H. pylori infection was assessed using a multiple logistic regression model. RESULTS: The prevalence of the H. pylori was similar in both genders (20.6% in men and 19.7% in women). H. pylori -infected participants had significantly higher body mass index, fasting glucose, low-density lipoprotein, and triglycerides, and lower high-density lipoprotein (p < 0.05), than uninfected ones (p < 0.05). The prevalence of metabolic syndrome was higher in H. pylori -infected subjects than uninfected ones (men: 12.4% vs. 7.4%, p < 0.001; women: 7.4% vs. 2.5%, p < 0.001). Furthermore, H. pylori infection prevalence increased with metabolic score (P for trend <0.001, both sexes). Moreover, the association between metabolic syndrome and UBT positivity was significant in females (OR 1.91, 95% CI:1.03-3.53), but only borderline significant in males (OR 1.38, 95% CI: 0.97-1.95). CONCLUSION: H. pylori infection is positively associated with metabolic syndrome, especially in females. The causal relationship between H. pylori infection and metabolic syndrome warrants further investigation.


Subject(s)
Helicobacter Infections/complications , Helicobacter pylori/isolation & purification , Metabolic Syndrome/complications , Adolescent , Adult , Asian People , Breath Tests , Cross-Sectional Studies , Female , Helicobacter Infections/diagnosis , Helicobacter Infections/epidemiology , Humans , Lipoproteins, HDL/metabolism , Lipoproteins, LDL/metabolism , Logistic Models , Male , Metabolic Syndrome/epidemiology , Middle Aged , Prevalence , Taiwan/epidemiology , Urea/metabolism , Young Adult
4.
Nutr Cancer ; 61(5): 735-45, 2009.
Article in English | MEDLINE | ID: mdl-19838948

ABSTRACT

Hepatocellular carcinoma (HCC) is the leading cause of cancer mortality in Asia. This study evaluated the growth inhibition effect of quercetin and 2-methoxyestradiol in vitro in human HCC cell lines. Combination treatment enhanced the cytotoxic effect in HA22T/VGH and HepG2 cell lines as compared with quercetin or 2-methoxyestradiol alone. The cell population of sub-G0/G1 phase and the level of annexin V binding were increased synergistically after combination treatment with quercetin and 2-methoxyestradiol in both cell lines. Moreover, quercetin combined with 2-methoxyestradiol increased superoxide levels, mitochondrial superoxide dismutase (MnSOD) in mRNA, protein levels, and SOD activity. Finally, we also found the mitochondrial membrane potential was decreased after combination treatment. The changes of reactive oxygen species and mitochondrial disruption were likely to be involved in the mechanism for the synergistic cytotoxicity effects of combination treatment in human hepatoma cells. These results provided a basis for further study of the potential usage of quercetin combination with hormonal agents for the treatment of human hepatoma.


Subject(s)
Antineoplastic Agents/administration & dosage , Antineoplastic Agents/pharmacology , Apoptosis , Estradiol/analogs & derivatives , Oxidative Stress , Quercetin/administration & dosage , 2-Methoxyestradiol , Annexin A5/metabolism , Apoptosis/drug effects , Carcinoma, Hepatocellular/therapy , Cell Cycle/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Estradiol/pharmacology , Flow Cytometry , Gene Expression Regulation, Neoplastic , Hep G2 Cells , Humans , Membrane Potential, Mitochondrial/drug effects , RNA, Messenger/metabolism , Reactive Oxygen Species/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism
5.
iScience ; 12: 270-279, 2019 Feb 22.
Article in English | MEDLINE | ID: mdl-30716700

ABSTRACT

Congenital microcephaly occurs in utero during Zika virus (ZIKV) infection. The single-gene disorder, Majewski osteodysplastic primordial dwarfism type II (MOPDII), also leads to microcephaly and is concomitant with a decrease in the centrosomal protein, pericentrin (PCNT). This protein is a known contributor of mitotic spindle misorientation and ultimately, microcephaly. Similar to MOPDII, either viral infection or interferon (IFN)-α exposure reduced PCNT levels at the mitotic spindle poles. We unexpectedly found that infection of cells with any one of a diverse set of viruses, such as ZIKV, dengue virus, cytomegalovirus, influenza A virus, or hepatitis B virus, or treatment of cells with the anti-viral cytokine, IFN-α, produced mitotic spindle misorientation. These findings demonstrate a related mechanism for the development of microcephaly in viral infection, the host's antiviral IFN response, and primordial dwarfism.

6.
Obes Res Clin Pract ; 12(4): 365-371, 2018.
Article in English | MEDLINE | ID: mdl-28411022

ABSTRACT

OBJECTIVE: To examine the prevalence of obesity and related cardiovascular disease risk factors among Tibetan immigrants living in high altitude areas. RESEARCH METHODS & PROCEDURES: A total of 149 Tibetan immigrants aged 20 years and over were recruited in 2016 in Ladakh, India. Anthropometric indices and biochemical factors were measured. Using the provided Asia-Pacific criteria from the World Health Organization, overweight and obese status were determined. Metabolic syndrome (MetS) was defined according to the American Heart Association. RESULTS: In general, men were older, taller, and had a greater amount of fasting glucose, and uric acid when compared to women. The prevalence of overweight, general obesity, and central obesity was 23.4, 42.6, and 42.6% in men and 7.8, 64.7, and 69.6% in women, respectively. The prevalence of MetS was 10.6% in men and 33.3% in women, respectively. In older subjects, the prevalence of obesity and MetS was found to be greater. In both genders, the prevalence of hypertension, central obesity, and MetS was significantly different among these body mass index (BMI) groups. Compared to the non-central obesity group, the central obesity group has higher weight, BMI, body fat, hip circumference, systolic and diastolic BP, and prevalence of hypertension. No relationship was found between the prevalence of diabetes and fasting glucose and BMI groups or central obesity groups in both genders. CONCLUSIONS: Among this group of Tibetan immigrants living in high altitude areas, women have a higher prevalence of obesity and MetS than men. No relationship was found between diabetes and obesity.


Subject(s)
Metabolic Syndrome/ethnology , Obesity/ethnology , Adult , Age Factors , Aged , Altitude , Emigrants and Immigrants , Female , Humans , India/epidemiology , Male , Metabolic Syndrome/epidemiology , Middle Aged , Obesity/epidemiology , Prevalence , Sex Factors , Tibet/ethnology
7.
Int J Infect Dis ; 73: 102-108, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29906602

ABSTRACT

OBJECTIVES: Despite the fact that vaccination is an effective primary prevention strategy for the containment of influenza outbreaks, health policymakers have shown great concern over the enormous costs involved in universal immunization, particularly when resources are limited. METHODS: A two-arm cost-effectiveness analysis (CEA) was conducted that took into account the aspect of herd immunity. The analysis used a study cohort of 100000 residents with a demographic make-up identical to that of the underlying population in Taipei County, Taiwan, during the epidemic influenza season of 2001-2002. The parameters embedded in the dynamic process of infection were estimated through the application of the newly proposed susceptible-infection-complication-recovery (SICR) model to the empirical data, in order to compute the number of deaths and complications averted due to universal vaccination compared to no vaccination. Incremental cost-effectiveness ratios (ICERs) and the cost-effectiveness acceptability curve (CEAC) given maximum amount of willingness-to-pay (WTP) were calculated to delineate the results of the two-arm CEA. RESULTS: The incremental costs involved in the vaccinated group as compared to the unvaccinated group were $1195 to reduce one additional complication and $805 to avert one additional death, allowing for herd immunity. The corresponding figures were higher for the results without considering herd immunity. Given the ceiling ratio of WTP equal to $10000 (approximately two-thirds of GDP), the probability of the vaccination being cost-effective for averting death was 100% and for averting complications was 96.7%. CONCLUSIONS: Universal vaccination against seasonal influenza was found to be very cost-effective, particularly when herd immunity is considered. The probability of being cost-effective was almost certain given the maximum amount of WTP within two-thirds of the GDP.


Subject(s)
Influenza Vaccines/immunology , Vaccination/economics , Cohort Studies , Cost-Benefit Analysis , Humans , Immunity, Herd , Influenza, Human/prevention & control
8.
Cilia ; 5: 13, 2016.
Article in English | MEDLINE | ID: mdl-26981235

ABSTRACT

In human cells, the basal body (BB) core comprises a ninefold microtubule-triplet cylindrical structure. Distal and subdistal appendages are located at the distal end of BB, where they play indispensable roles in cilium formation and function. Most cells that arrest in the G0 stage of the cell cycle initiate BB docking at the plasma membrane followed by BB-mediated growth of a solitary primary cilium, a structure required for sensing the extracellular environment and cell signaling. In addition to the primary cilium, motile cilia are present in specialized cells, such as sperm and airway epithelium. Mutations that affect BB function result in cilia dysfunction. This can generate syndromic disorders, collectively called ciliopathies, for which there are no effective treatments. In this review, we focus on the features and functions of BBs and centrosomes in Homo sapiens.

9.
Curr Biol ; 26(6): 793-801, 2016 Mar 21.
Article in English | MEDLINE | ID: mdl-26948879

ABSTRACT

Establishing apical-basal polarity is instrumental in the functional shaping of a solitary lumen within an acinus. By exploiting micropatterned slides, wound healing assays, and three-dimensional culture systems, we identified a mother centriole subdistal appendage protein, cenexin, as a critical player in symmetric lumen expansion through the control of microtubule organization. In this regard, cenexin was required for both centrosome positioning in interphase cells and proper spindle orientation during mitosis. In contrast, the essential mother centriole distal appendage protein CEP164 did not play a role in either process, demonstrating the specificity of subdistal appendages for these events. Importantly, upon closer examination we found that cenexin depletion decreased astral microtubule length, disrupted astral microtubule minus-end organization, and increased levels of the polarity protein NuMA at the cell cortex. Interestingly, spindle misorientation and NuMA mislocalization were reversed by treatment with a low dose of the microtubule-stabilizing agent paclitaxel. Taken together, these results suggest that cenexin modulates microtubule organization and stability to mediate spindle orientation.


Subject(s)
Heat-Shock Proteins/metabolism , Spindle Apparatus/metabolism , Animals , Antigens, Nuclear/genetics , Antigens, Nuclear/metabolism , Cell Cycle Proteins , Cell Line , Cell Movement , Centrioles/metabolism , Centrosome/metabolism , Dogs , Epithelial Cells , Heat-Shock Proteins/genetics , Humans , Madin Darby Canine Kidney Cells , Microtubule Proteins/genetics , Microtubule Proteins/metabolism , Microtubules/drug effects , Microtubules/metabolism , Nocodazole/pharmacology , Nuclear Matrix-Associated Proteins/genetics , Nuclear Matrix-Associated Proteins/metabolism
10.
Sci Rep ; 6: 27034, 2016 06 01.
Article in English | MEDLINE | ID: mdl-27246655

ABSTRACT

Non-alcoholic fatty liver disease (NAFLD) is an emerging chronic liver disease that may lead to liver cirrhosis and hepatocellular carcinoma. We aimed to determine the association between the prevalence of metabolic syndrome (MetS) and NAFLD severity using semi-quantitative ultrasonography (US). A total of 614 participants were recruited from the community. NAFLD was evaluated according to the ultrasonographic Fatty Liver Indicator (US-FLI), which is a semi-quantitative liver ultrasound score. Insulin resistance was estimated with the homeostasis model assessment index for insulin resistance (HOMA-IR). NAFLD and MetS were found in 53.7 and 17.3% of the participants, respectively. Linear relationships were found between the severity of NAFLD and waist circumference, fasting glucose, HOMA-IR, triglycerides, HDL-C and blood pressure. After adjusting for confounding factors, i.e., body mass index and HOMA-IR, the odds ratios for MetS were 3.64 (95% confidence interval (CI): 1.5-8.83) for those with mild NAFLD and 9.4 (95% CI: 3.54-24.98) for those with moderate-to-severe NAFLD compared to those without NAFLD. The combination of the HOMA-IR and US-FLI scores better differentiated MetS than the HOMA-IR alone. In addition to obesity, the severity of NAFLD and the HOMA-IR both play important roles in MetS. Whether NAFLD is a component of MetS warrants further research.


Subject(s)
Insulin Resistance , Metabolic Syndrome/complications , Non-alcoholic Fatty Liver Disease/complications , Obesity, Abdominal/blood , Adult , Body Mass Index , China/epidemiology , Female , Humans , Insulin/blood , Male , Metabolic Syndrome/blood , Metabolic Syndrome/diagnostic imaging , Metabolic Syndrome/epidemiology , Middle Aged , Non-alcoholic Fatty Liver Disease/blood , Non-alcoholic Fatty Liver Disease/diagnostic imaging , Non-alcoholic Fatty Liver Disease/epidemiology , Obesity, Abdominal/diagnostic imaging , Obesity, Abdominal/epidemiology , Obesity, Abdominal/pathology , Odds Ratio , Prevalence , Risk Factors , Severity of Illness Index , Triglycerides/blood , Ultrasonography , Waist Circumference
11.
Methods Cell Biol ; 130: 47-58, 2015.
Article in English | MEDLINE | ID: mdl-26360027

ABSTRACT

For some time, it has been known that recycling endosomes (REs) are organized in a nebulous "pericentrosomal" region in interphase cells. However, the collective use of previously developed methods, including centrosome isolation, live cell imaging, and electron microscopy, suggested that there is much more going on between the centrosome and the RE than previously imagined. By exploiting these approaches, we uncovered novel roles of the centrosome in RE function and, conversely, novel roles for REs in centrosome function. We first found that REs dynamically localized to the centrosome throughout the cell cycle. More specifically, we found that REs interacted with appendages of the older centriole in interphase cells to control endosome recycling, and this interaction was governed by RE-machinery including the small GTPase Rab11. We next determined that REs carry centrosome proteins to spindle poles as part of the "centrosome maturation" process. Here we discuss the methods used and materials needed to complete these types of studies.


Subject(s)
Centrosome/physiology , Endosomes/physiology , Centrosome/ultrastructure , Endosomes/ultrastructure , HeLa Cells , Humans , Microscopy, Confocal , Microscopy, Electron, Transmission , Mitosis
12.
Curr Biol ; 24(19): 2327-2334, 2014 Oct 06.
Article in English | MEDLINE | ID: mdl-25220058

ABSTRACT

Majewski osteodysplastic primordial dwarfism type II (MOPDII) is caused by mutations in the centrosome gene pericentrin (PCNT) that lead to severe pre- and postnatal growth retardation. As in MOPDII patients, disruption of pericentrin (Pcnt) in mice caused a number of abnormalities including microcephaly, aberrant hemodynamics analyzed by in utero echocardiography, and cardiovascular anomalies; the latter being associated with mortality, as in the human condition. To identify the mechanisms underlying these defects, we tested for changes in cell and molecular function. All Pcnt(-/-) mouse tissues and cells examined showed spindle misorientation. This mouse phenotype was associated with misdirected ventricular septal growth in the heart, decreased proliferative symmetric divisions in brain neural progenitors, and increased misoriented divisions in fibroblasts; the same phenotype was seen in fibroblasts from three MOPDII individuals. Misoriented spindles were associated with disrupted astral microtubules and near complete loss of a unique set of centrosome proteins from spindle poles (ninein, Cep215, centriolin). All these proteins appear to be crucial for microtubule anchoring and all interacted with Pcnt, suggesting that Pcnt serves as a molecular scaffold for this functionally linked set of spindle pole proteins. Importantly, Pcnt disruption had no detectable effect on localization of proteins involved in the cortical polarity pathway (NuMA, p150(glued), aPKC). Not only do these data reveal a spindle-pole-localized complex for spindle orientation, but they identify key spindle symmetry proteins involved in the pathogenesis of MOPDII.


Subject(s)
Antigens/genetics , Dwarfism/genetics , Fetal Growth Retardation/genetics , Microcephaly/genetics , Microtubules/genetics , Mitosis , Osteochondrodysplasias/genetics , Spindle Apparatus/genetics , Animals , Antigens/metabolism , Centrosome/metabolism , Disease Models, Animal , Dwarfism/physiopathology , Embryo, Mammalian/embryology , Fetal Growth Retardation/physiopathology , Humans , Mice , Microcephaly/physiopathology , Osteochondrodysplasias/physiopathology , Spindle Apparatus/metabolism , Spindle Poles/genetics , Spindle Poles/metabolism
13.
Oncol Rep ; 27(2): 529-34, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22076474

ABSTRACT

1,6-Bis[4-(4-amino-3-hydroxyphenoxy)phenyl]diamantane (DPD) induces growth inhibition in human cancer cells. In our previous study, we discovered that DPD irreversibly inhibits the growth of Colo 205 colon cancer cells at the G0/G1 phase and induces cell differentiation. However, the detailed mechanism is still unknown. In this study, we examined the functional importance of p21 and p53 in DPD-induced anticancer effects. We used three isogenic cell lines, HCT-116, HCT-116 p53-/- and HCT-116 p21-/-, to evaluate the roles of p21 and p53 in the inĀ vitro anticancer effects of DPD. The inĀ vivo anti-proliferative effect of DPD was demonstrated by HCT-116 and HCT-116 p21-/- xenograft models. DPD significantly inhibited the growth as well as increased the number of HCT-116 cells in the G0/G1 phase, but not in HCT-116 p53-/- and HCT-116 p21-/- cells examined by flow cytometry. Additionally, western blot analysis showed that DPD treatment induced p21, but not p53 protein expression in HCT-116 cells. The p21-associated cell cycle regulated proteins, such as cyclin D, CDK4 and pRb were decreased after DPD treatment in HCT-116 cells. The DPD-increased G0/G1 phase and induced cell cycle regulated protein expression were not observed in HCT-116 p21-/- and HCT-116 p53-/- cells. DPD decreased cell migration in HCT-116 and HCT-116 p53-/- but not in HCT-116 p21-/- cells. p21 was required for the DPD-induced inĀ vitro anti-colon cancer effect. The inĀ vivo study also showed that DPD significantly inhibited tumor growth through p21 signaling. Our results clearly demonstrate that DPD-induced inĀ vitro and inĀ vivo anticancer effects through the activation of p21 in HCT-116 cells.


Subject(s)
Adamantane/analogs & derivatives , Antineoplastic Agents/pharmacology , Carcinoma/metabolism , Colonic Neoplasms/metabolism , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Adamantane/pharmacology , Animals , Antineoplastic Agents/therapeutic use , Carcinoma/drug therapy , Carcinoma/genetics , Cell Cycle/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Cell Movement/genetics , Cell Proliferation/drug effects , Colonic Neoplasms/drug therapy , Colonic Neoplasms/genetics , Cyclin-Dependent Kinase Inhibitor p21/genetics , HCT116 Cells , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Signal Transduction/drug effects , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
14.
Pharmacoeconomics ; 29(12): 1063-73, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22077578

ABSTRACT

BACKGROUND: As neonates born to mothers with positive hepatitis B e antigen may not be completely protected by hepatitis B vaccination, prophylactic lamivudine use in mothers with high viraemia has been proposed. However, the overall effectiveness and the balance between cost and benefit for such a prophylactic strategy have rarely been addressed. OBJECTIVE: Using a review of recent literature, we aimed to assess the cost effectiveness, from the Taiwanese societal perspective, of administering prophylactic lamivudine to mothers to reduce vertical transmission of hepatitis B virus and its long-term sequelae in neonates. METHODS: A meta-analysis of three randomized controlled trials was conducted to evaluate the efficacy of lamivudine versus placebo. A Markov decision model was constructed in which in both treatment arms infants received active and passive immunoprophylaxis. An economic evaluation was performed to calculate costs, acute infections averted, and QALYs gained. Probabilistic sensitivity analyses were conducted and a cost-effectiveness acceptability curve drawn. All these analyses were from the societal perspective. Costs ($US) were valued in year 2008 prices. RESULT: Supplemental lamivudine use gained an additional 0.0024 QALYs and averted 0.23 acute infections per birth compared with the routine active-passive immunization without lamivudine. The cost-effectiveness analysis suggested that the use of additional prophylactic lamivudine dominated the routine strategy. The acceptability curve suggested that the probability of being cost effective under the willingness-to-pay threshold of $US20,000 was 94%. CONCLUSION: This analysis suggests that supplemental use of lamivudine in mothers with high hepatitis B viraemia is effective in reducing vertical transmission and may be cost effective, from a Taiwanese societal perspective, compared with the routine active-passive immunization without lamivudine.


Subject(s)
Antiviral Agents/economics , Health Care Costs/statistics & numerical data , Hepatitis B/economics , Infectious Disease Transmission, Vertical/prevention & control , Lamivudine/economics , Primary Prevention/economics , Antiviral Agents/therapeutic use , Cost of Illness , Cost-Benefit Analysis , Hepatitis B/drug therapy , Hepatitis B/prevention & control , Hepatitis B/transmission , Hepatitis B virus/immunology , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/economics , Hepatitis B, Chronic/prevention & control , Hepatitis B, Chronic/transmission , Humans , Lamivudine/therapeutic use , Quality-Adjusted Life Years , Taiwan
16.
J Eval Clin Pract ; 17(6): 1050-8, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21679279

ABSTRACT

INTRODUCTION: As the effectiveness of cytology-based screening programme for cervical cancer in mortality reduction has reached a plateau, various preventive strategies have been considered, including intensive Pap smear screening and the supplemental use of human papillomavirus (HPV) DNA test or HPV vaccination. Cost and effectiveness of these various preventive strategies are therefore of great concern for health policy makers. OBJECTIVE: We intended to assess whether the combination of HPV DNA testing or HPV vaccination with Pap smear screening programme or the sole annual Pap smear screening is more effective and cost-effective in prevention of cervical cancer than the existing triennial Pap smear screening programme. METHODS: A Markov decision model was constructed to compare total costs and effectiveness between different preventive strategies (including annual Pap smear, HPV DNA testing or HPV vaccination together with Pap smear screening programme) as opposed to the triennial Pap smear screening alone (the comparator). Probabilistic cost-effectiveness (C-E) analysis was adopted to plot a series of simulated incremental C-E ratios scattered over C-E plane and also to yield the acceptability curve for different comparisons of strategies. The threshold of vaccine cost and the influence of attendance rate were also investigated. RESULTS: Compared with triennial Pap smear screening programme, most of preventive strategies cost more but gain additional life years (quadrant I of C-E plane) except HPV DNA testing with Pap smear every 5 years dominated by triennial Pap smear screening programme. The most cost-effective strategy was annual Pap smear (incremental C-E ratio = $31 698), followed by HPV DNA testing with Pap smear every 3 years ($36 627), and vaccination programme with triennial Pap smear screening ($44 688) with the corresponding cost-effective probabilities by the acceptability curve being 65.52%, 52.08% and 35.84% given the threshold of $40 000 of willingness to pay. Vaccination combined with triennial Pap smear would be as cost-effective as annual Pap smear provided the cost of vaccination was lowered to $250 per full course of injection. CONCLUSIONS: Among various preventive strategies annual Pap smear screening programme is still the most cost-effective and additional HPV DNA testing is a cost-effective choice under a reasonable threshold of willingness to pay. Vaccination programme in combination with triennial screening would be cost-effective if vaccine cost can be greatly reduced in a large economic scale.


Subject(s)
Alphapapillomavirus/genetics , DNA, Viral/genetics , Papanicolaou Test , Papillomavirus Vaccines/administration & dosage , Papillomavirus Vaccines/economics , Uterine Cervical Neoplasms/prevention & control , Vaginal Smears/economics , Cost-Benefit Analysis , Female , Humans , Markov Chains , Mass Screening/economics , Taiwan , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/economics
17.
Vaccine ; 27(48): 6770-6, 2009 Nov 12.
Article in English | MEDLINE | ID: mdl-19735755

ABSTRACT

AIM: To assess cost-effectiveness of hepatitis B virus (HBV) vaccination strategies from health care payer and societal perspectives, focusing on the long-term effect, in Taiwan where prevalence of HBV and Hepatitis B e Antigen (HBeAg) is high. METHODS: A decision analysis was performed to compare total costs and effectiveness between two vaccination strategies: universal vaccination and no-vaccination. The Markov process was defined as a series of states including acute HBV infection, asymptomatic carrier, chronic hepatitis, compensated and decompensated liver cirrhosis, hepatoma, and death. Direct and indirect costs were also imputed based on estimates. The incremental cost-effectiveness ratio (ICER) per life-year gained and quality-adjusted life years gained were calculated at a 3% discount rate. By assigning a series of specific distributions to each parameter, a probabilistic cost-effective analysis using Monte Carlo simulation was conducted to yield 5000 ICER replicates. RESULTS: The effectiveness of a universal vaccination program for reducing hepatocellular carcinoma cases and deaths was approximately 86%. The average life years gained per subject as a result of such a universal vaccination was 3.9. The vaccination program dominated over a no-vaccination program (less cost and more effectiveness). CONCLUSIONS: A universal vaccination program against hepatitis B infection is not only effective for reducing long-term sequelae but is also a cost-saving primary preventive strategy, which supports a universal infant immunization in endemic area with high prevalence of HBV and HBeAg.


Subject(s)
Hepatitis B Vaccines/economics , Hepatitis B/epidemiology , Immunization Programs/economics , Carcinoma, Hepatocellular/epidemiology , Carcinoma, Hepatocellular/prevention & control , Cost-Benefit Analysis , Decision Support Techniques , Hepatitis B/prevention & control , Hepatitis B e Antigens/immunology , Humans , Infant , Infant, Newborn , Markov Chains , Mass Vaccination , Models, Economic , Monte Carlo Method , Prevalence , Quality-Adjusted Life Years , Taiwan/epidemiology
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