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1.
Polymers (Basel) ; 16(7)2024 Mar 24.
Article in English | MEDLINE | ID: mdl-38611147

ABSTRACT

The development of high-performance filtration materials is essential for the effective removal of airborne particles, and metal-organic frameworks (MOFs) anchored to organic polymer matrices are considered to be one of the most promising porous adsorbents for air pollutants. Nowadays, most air filters are generally based on synthetic fiber polymers derived from petroleum residues and have limited functionality, so the use of MOFs in combination with nanofiber air filters has received a lot of attention. Here, a conjugated electrostatic spinning method is demonstrated for the one-step preparation of poly(lactic acid) (PLA) nanofibrous membranes with a bimodal diameter distribution and the anchoring of Zeolitic Imidazolate Framework-8 (ZIF-8) by the introduction of TiO2 and in situ generation to construct favorable multiscale fibers and rough structures. The prepared PLA/TZ maintained a good PM2.5 capture efficiency of 99.97%, a filtration efficiency of 96.43% for PM0.3, and a pressure drop of 96.0 Pa, with the highest quality factor being 0.08449 Pa-1. Additionally, ZIF-8 was uniformly generated on the surface of PLA and TiO2 nanofibers, obtaining a roughened structure and a larger specific surface area. An enhanced filtration retention effect and electrostatic interactions, as well as active free radicals, can be generated for the deep inactivation of bacteria. Compared with the unmodified membrane, PLA/TZ prepared antibacterial characteristics induced by photocatalysis and Zn2+ release, with excellent bactericidal effects against S. aureus and E. coli. Overall, this work may provide a promising approach for the development of efficient biomass-based filtration materials with antimicrobial properties.

2.
RSC Adv ; 14(20): 14100-14113, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38686297

ABSTRACT

With the escalating air pollution and frequent outbreaks of airborne diseases, there is a growing demand for personal protective filtration media. Melt-blown nonwovens have proven to be highly effective in capturing tiny particles, but their tightly packed fiber assemblages are more resistant to airflow and less comfortable to breathe. Here, we present a one-step melt-blown spinning process for the production of bicomponent core/sheath (BCS) crimped fibers and their application in high-efficiency, low-resistance air filtration. Fiber curl is caused by unbalanced internal stresses resulting from differences in the structure components, resulting in uneven shrinkage inside and outside the fibers. The resulting CM@S-2 filtration media features a uniform fiber curl and a porous fiber mesh structure, which reduces air filtration resistance. Under the same filtration conditions, the filtration efficiency of CM@S-2 (96.58% vs. 95.58%), filtration resistance (56.1 Pa vs. 108.0 Pa), quality factor (0.061 Pa-1vs. 0.029 Pa-1), and dust holding capacity (10.60 g m-2vs. 9.10 g m-2) were comparable to those of the single-component polypropylene filters. The filtration efficiency of the CM@S-2 remained above 94.0% after 30 days of indoor storage. Computational Fluid Dynamics (CFD) simulation demonstrated that crimped fibers effectively reduce pressure surges on the filter media caused by fiber accumulation. In comparative tests with commercial masks, the CM@S-2 cartridge masks demonstrated superior air permeability compared to commercial masks under similar filtration conditions. In conclusion, the bicomponent core/sheath melt-blown fibers significantly reduce air resistance and show excellent potential for application in protective masks.

3.
RSC Adv ; 13(44): 30680-30689, 2023 Oct 18.
Article in English | MEDLINE | ID: mdl-37869388

ABSTRACT

Electrospun nanofiber membranes have been extensively studied as air filters. However, their limited filtration efficiency for submicron inhalable particulate matter (PM), high resistance to filtration, and limited capacity to hold dust have hindered their widespread use. The majority of materials come from petroleum, and the use of organic solvents during the spinning process has a significant negative impact on the environment. In this work, a sustainable method has been proposed for producing filters using poly(lactic acid) (PLA) with a bimodal diameter distribution through conjugated electrospinning. This technique allows for the continuous production of interconnected micro/nano hybrid porous membranes, resulting in reduced resistance and improved dust holding capacity. The filtration efficiency, pressure drop, long-term filtration performance, and actual performance of the conjugated bimodal membrane (CBM) were extensively investigated. The results indicate that the filter has a high capacity for retaining particles, with filtration efficiencies of 99.94% for PM 0.3 and 99.96% for PM 2.5. It also demonstrates a high quality factor (0.078 Pa-1 for PM 0.3 and 0.084 Pa-1 for PM 2.5), long-term stability (a decrease of 2.35% for PM 0.3 and 0.05% for PM 2.5 over a period of 60 days) and outstanding dust holding capacity (9.17 g m-2). The conjugated bimodal membrane (CBM) shows a 22.64% decrease in resistance compared to the non-conjugated bimodal membrane (BM). In general, the approach outlined in this work provides valuable insights into the development of high-performance biodegradable air filters. These filters have improved filtration efficiency and reduced resistance.

4.
Polymers (Basel) ; 15(16)2023 Aug 10.
Article in English | MEDLINE | ID: mdl-37631422

ABSTRACT

Particulate matter (PM) and airborne viruses pose significant threats to both the environment and public health. As the most viable solution to prevent the inhalation of these pollutants, there is an urgent demand for face masks with excellent filtration efficiency and low-pressure drop. In this study, a crimped masterbatch (CM) is added to polypropylene feedstocks to produce curling fibers through melt-blown spinning. These curled fibers exhibit low filtration resistance and effective dust-holding performances when used for air filtration. The effect of adding CM on fiber diameter, pore size, crimp, porosity, roughness, and surface potential was studied. The filtration performance of the materials, including the PM filtration capabilities, recirculation filtration, and loading test performance, were also investigated. The results demonstrate that the degree of fiber crimp can be adjusted by incorporating varying amounts of CM. This curling was caused by the uneven shrinkage that occurred due to variations in thermal contraction between these polymers. The curled fibers created a fluffy structure in the fiber network and modified the distribution of pore sizes within it. Under the same filtration conditions as sodium chloride aerogel, CM-2 (PP:CM 8:2) exhibited similar filtration efficiency (95.54% vs. 94.74%), lower filtration resistance (88.68 Pa vs. 108.88 Pa), higher quality factor (0.035 Pa-1 vs. 0.028 Pa-1) and better dust holding capacity (10.39 g/m2 vs. 9.20 g/m2) compared to CM-0 (PP:CM 10:0). After 30 days of indoor storage, the filtration efficiency of CM-2 remained above 94%. The self-curling melt-blown filtration material developed here could potentially be applied in the field of protective masks.

5.
Polymers (Basel) ; 15(6)2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36987239

ABSTRACT

Particulate matter (PM) with a diameter of 0.3 µm is inhalable and brings great threats to human health. Traditional meltblown nonwovens used for air filtration need to be treated by high voltage corona charging, which has the problem of electrostatic dissipation and thus reduces the filtration efficiency. In this work, a kind of composite air-filter with high efficiency and low resistance was fabricated by alternating lamination of ultrathin electronspun nano-layer and melt-blown layer without corona charging treatment. The effects of fiber diameter, pore size, porosity, layer number, and weight on filtration performance were investigated. Meanwhile, the surface hydrophobicity, loading capacity, and storage stability of the composite filter were studied. The results indicate that the filters (18.5 gsm) laminated by 10 layers fiber-webs present excellent filtration efficiency (97.94%), low pressure drop (53.2 Pa), high quality factor (QF 0.073 Pa-1), and high dust holding capacity (9.72 g/m2) for NaCl aerosol particles. Increasing the layers and reducing individual layer weight can significantly improve filtration efficiency and reduce pressure drop of the filter. The filtration efficiency decayed slightly from 97.94% to 96.48% after 80 days storage. The alternate arrangement of ultra-thin nano and melt-blown layers constructed a layer-by-layer interception and collaborative filtering effect in the composite filter, realizing the high filtration efficiency and low resistance without high voltage corona charging. These results provided new insights for the application of nonwoven fabrics in air filtration.

6.
Comput Math Methods Med ; 2022: 6879035, 2022.
Article in English | MEDLINE | ID: mdl-36118840

ABSTRACT

Objective: This study is aimed at exploring the efficacy of transarterial chemotherapy embolization (TACE)+radiofrequency ablation+sorafenib in the treatment of patients with recurrent liver cancer and at constructing its prediction model. Methods: A total of 60 patients with recurrent liver cancer treated in our hospital from March 2020 to March 2022 were enrolled and divided into two groups according to treatment methods, with 30 patients in each group. Group A adopted TACE+radiofrequency ablation+sorafenib therapy while group B adopted TACE+radiofrequency ablation therapy. Clinical efficacy, complications, and adverse reactions of the two groups were observed. A total of 30 patients with nonrecurrent liver cancer in the same period were enrolled. 60 patients with recurrent liver cancer and 30 patients with nonrecurrent liver cancer were taken as the recurrence group and the nonrecurrence group, respectively. The baseline data and clinical data of the patients were queried by the Hospital Information System. The data included age, gender, Child-Pugh grade, HBV/HCV infection, portal vein tumor thrombus, degree of differentiation, vascular invasion, serum alpha fetal protein (AFP) level, number of tumors, maximum diameter of tumors, and number of nodules. The logistic regression analysis was used to analyze the independent risk factors for liver cancer recurrence. The Hosmer-Lemeshow test was used to analyze the degree of fitting between the prediction model and the standard curve. The ROC curve was used to analyze the predictive value of the model for liver cancer recurrence. Results: The objective effective rate and disease control rate in group A (33.33% and 70.00%) were higher than those in group B (10.00% and 43.33%), and the differences were statistically significant (both P < 0.05). There were no significant differences in the incidence of complications such as embolism syndrome, hand and foot skin reaction, gastrointestinal reaction, hypertension, diaphragmatic injury and bleeding, and biliary leakage and fever between the two groups (all P > 0.05). The proportions of patients in the recurrence group with portal vein tumor thrombus (PVTT), medium and high degree of differentiation, combined with vascular invasion, serum AFP level ≥ 400 ng/dL, multiple tumors, maximum tumor diameter ≥ 5 cm, combined with cirrhosis, and polynodules were all higher than those in the nonrecurrence group; the differences were statistically significant (all P < 0.05). Complication of PVTT, the degree of medium and high differentiation, and the maximum tumor diameter ≥ 5 cm were independent risk factors for recurrence of liver cancer (all P < 0.05). The prediction model of liver cancer recurrence was obtained by multiple regression analysis, P = 1/[1 + e -(-5.441 + 6.154∗PVTT + 3.475∗differentiateddegree + 3.001∗maximumdiameteroftumor)]. The Hosmer-Lemeshow test showed that χ 2 = 1.558 (P = 0.992). According to the ROC curve analysis, the AUC, SE, and 95% CI value of the prediction model for liver cancer recurrence were 0.977, 0.012, and 0.953-1.000, respectively. Conclusion: TACE+radiofrequency ablation+sorafenib is effective in the treatment of recurrent liver cancer, and the prediction model established based on the risk factor has high predictive value for patients with recurrent liver cancer.


Subject(s)
Carcinoma, Hepatocellular , Catheter Ablation , Chemoembolization, Therapeutic , Liver Neoplasms , Thrombosis , Carcinoma, Hepatocellular/surgery , Catheter Ablation/adverse effects , Chemoembolization, Therapeutic/methods , Chronic Disease , Combined Modality Therapy , Humans , Liver Neoplasms/surgery , Sorafenib/therapeutic use , Thrombosis/therapy , alpha-Fetoproteins/therapeutic use
7.
BMJ Nutr Prev Health ; 5(1): 1-9, 2022.
Article in English | MEDLINE | ID: mdl-35814719

ABSTRACT

Ultra-processed food intake has been linked to an increased risk of breast cancer in Western populations. No data are available in the Latin American population although the consumption of ultra-processed foods is increasing rapidly in this region. We evaluated the association of ultra-processed food intake to breast cancer risk in a case-control study including 525 cases (women aged 20-45 years) and 525 matched population-based controls from Chile, Colombia, Costa Rica and Mexico. The degree of processing of foods was classified according to the NOVA classification. Overall, the major contributors to ultra-processed food intake were ready-to-eat/heat foods (18.2%), cakes and desserts (16.7%), carbonated and industrial fruit juice beverages (16.7%), breakfast cereals (12.9%), sausages and reconstituted meat products (12.1%), industrial bread (6.1%), dairy products and derivatives (7.6%) and package savoury snacks (6.1%). Ultra-processed food intake was positively associated with the risk of breast cancer in adjusted models (OR T3-T1=1.93; 95% CI=1.11 to 3.35). Specifically, a higher risk was observed with oestrogen receptor positive breast cancer (ORT3-T1=2.44, (95% CI=1.01 to 5.90, P-trend=0.049), while no significant association was observed with oestrogen receptor negative breast cancer (ORT3-T1=1.87, 95% CI=0.43 to 8.13, P-trend=0.36). Our findings suggest that the consumption of ultra-processed foods might increase the risk of breast cancer in young women in Latin America. Further studies should confirm these findings and disentangle specific mechanisms relating ultra-processed food intake and carcinogenic processes in the breast.

8.
Sci Rep ; 10(1): 2294, 2020 02 10.
Article in English | MEDLINE | ID: mdl-32042008

ABSTRACT

Cumulating evidence in Caucasian women suggests a positive association between height and premenopausal breast cancer risk and a negative association with overall adiposity; however data from Latin America are scarce. We investigated the associations between excess adiposity, body shape evolution across life, and risk of premenopausal breast cancer among 406 cases (women aged 20-45) and 406 matched population-based controls from Chile, Colombia, Costa Rica, and Mexico. Negative associations between adult adiposity and breast cancer risk were observed in adjusted models (body mass index (BMI): Odds ratio (OR) per 1 kg/m2 = 0.93; 95% confidence interval = 0.89-0.96; waist circumference (WC): OR per 10 cm = 0.81 (0.69-0.96); hip circumference (HC): OR per 10 cm = 0.80 (0.67-0.95)). Height and leg length were not associated with risk. In normal weight women (18.5 ≤ BMI < 25), women with central obesity (WC > 88 cm) had an increased risk compared to women with normal WC (OR = 3.60(1.47-8.79)). Residuals of WC over BMI showed positive associations when adjusted for BMI (OR per 10 cm = 1.38 (0.98-1.94)). Body shape at younger ages and body shape evolution were not associated with risk. No heterogeneity was observed by receptor status. In this population of Latin American premenopausal women, different fat distributions in adulthood were differentially associated with risk of breast cancer.


Subject(s)
Adiposity/physiology , Breast Neoplasms/epidemiology , Obesity, Abdominal/epidemiology , Premenopause , Waist Circumference/physiology , Adult , Body Mass Index , Breast Neoplasms/physiopathology , Case-Control Studies , Female , Humans , Incidence , Latin America/epidemiology , Middle Aged , Obesity, Abdominal/physiopathology , Risk Factors , Young Adult
9.
Nutr Res ; 36(8): 863-71, 2016 08.
Article in English | MEDLINE | ID: mdl-27440541

ABSTRACT

Equol (a bacterial metabolite of the soy isoflavone daidzein) is produced by 30% to 50% of humans and may be associated with health outcomes. We hypothesized that plasma equol would be inversely associated with risks of fibrocystic breast conditions (FBC) and breast cancer (BC). Plasma from women in a breast self-examination trial in Shanghai with BC (n=269) or FBC (n=443), and age-matched controls (n=1027) was analyzed for isoflavones. Equol was grouped into categories (<20, 20-<45, and ≥45nmol/L) and, among women with daidzein ≥20nmol/L, the log10 equol:daidzein ratio was grouped into tertiles. Where available, non-cancerous tissue (NCT) adjacent to the carcinomas from women with BC were classified as non-proliferative or proliferative (n=130 and 172, respectively). The lesions from women with FBC were similarly classified (n=99 and 92, respectively). Odds ratios (OR) and 95% confidence intervals (CI) were calculated across equol categories and tertiles of log10 equol:daidzein ratio. Equol categories were not associated with FBC or BC (P>.05). For log10 equol:daidzein, compared to controls there were positive associations in the mid tertile for proliferative FBC (OR 2.06, 95% CI 1.08-3.93), BC with proliferative NCT (OR 2.95, 95% CI 1.37-6.35), and all BC regardless of histology (OR 2.37, 95% CI 1.43-3.95). However, trends in ORs with increasing plasma equol values or equol:daidzein ratios were not observed (P>.05). The results of this study do not provide evidence that equol plays a role in the etiology of these breast conditions. However, further work is needed to confirm or refute this conclusion.


Subject(s)
Breast Neoplasms/blood , Equol/blood , Fibrocystic Breast Disease/blood , Adult , Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Breast Self-Examination , Case-Control Studies , China/epidemiology , Female , Fibrocystic Breast Disease/epidemiology , Fibrocystic Breast Disease/pathology , Humans , Isoflavones/blood , Middle Aged , Odds Ratio
10.
NPJ Breast Cancer ; 2: 16014, 2016.
Article in English | MEDLINE | ID: mdl-28721378

ABSTRACT

Pathological analysis of the nuclear proliferation biomarker Ki67 has multiple potential roles in breast and other cancers. However, clinical utility of the immunohistochemical (IHC) assay for Ki67 immunohistochemistry has been hampered by unacceptable between-laboratory analytical variability. The International Ki67 Working Group has conducted a series of studies aiming to decrease this variability and improve the evaluation of Ki67. This study tries to assess whether acceptable performance can be achieved on prestained core-cut biopsies using a standardized scoring method. Sections from 30 primary ER+ breast cancer core biopsies were centrally stained for Ki67 and circulated among 22 laboratories in 11 countries. Each laboratory scored Ki67 using three methods: (1) global (4 fields of 100 cells each); (2) weighted global (same as global but weighted by estimated percentages of total area); and (3) hot-spot (single field of 500 cells). The intraclass correlation coefficient (ICC), a measure of interlaboratory agreement, for the unweighted global method (0.87; 95% credible interval (CI): 0.81-0.93) met the prespecified success criterion for scoring reproducibility, whereas that for the weighted global (0.87; 95% CI: 0.7999-0.93) and hot-spot methods (0.84; 95% CI: 0.77-0.92) marginally failed to do so. The unweighted global assessment of Ki67 IHC analysis on core biopsies met the prespecified criterion of success for scoring reproducibility. A few cases still showed large scoring discrepancies. Establishment of external quality assessment schemes is likely to improve the agreement between laboratories further. Additional evaluations are needed to assess staining variability and clinical validity in appropriate cohorts of samples.

11.
Mod Pathol ; 28(6): 778-86, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25698062

ABSTRACT

Although an important biomarker in breast cancer, Ki67 lacks scoring standardization, which has limited its clinical use. Our previous study found variability when laboratories used their own scoring methods on centrally stained tissue microarray slides. In this current study, 16 laboratories from eight countries calibrated to a specific Ki67 scoring method and then scored 50 centrally MIB-1 stained tissue microarray cases. Simple instructions prescribed scoring pattern and staining thresholds for determination of the percentage of stained tumor cells. To calibrate, laboratories scored 18 'training' and 'test' web-based images. Software tracked object selection and scoring. Success for the calibration was prespecified as Root Mean Square Error of scores compared with reference <0.6 and Maximum Absolute Deviation from reference <1.0 (log2-transformed data). Prespecified success criteria for tissue microarray scoring required intraclass correlation significantly >0.70 but aiming for observed intraclass correlation ≥0.90. Laboratory performance showed non-significant but promising trends of improvement through the calibration exercise (mean Root Mean Square Error decreased from 0.6 to 0.4, Maximum Absolute Deviation from 1.6 to 0.9; paired t-test: P=0.07 for Root Mean Square Error, 0.06 for Maximum Absolute Deviation). For tissue microarray scoring, the intraclass correlation estimate was 0.94 (95% credible interval: 0.90-0.97), markedly and significantly >0.70, the prespecified minimum target for success. Some discrepancies persisted, including around clinically relevant cutoffs. After calibrating to a common scoring method via a web-based tool, laboratories can achieve high inter-laboratory reproducibility in Ki67 scoring on centrally stained tissue microarray slides. Although these data are potentially encouraging, suggesting that it may be possible to standardize scoring of Ki67 among pathology laboratories, clinically important discrepancies persist. Before this biomarker could be recommended for clinical use, future research will need to extend this approach to biopsies and whole sections, account for staining variability, and link to outcomes.


Subject(s)
Biomarkers, Tumor/analysis , Breast Neoplasms/pathology , Immunohistochemistry/standards , Ki-67 Antigen/analysis , Tissue Array Analysis/standards , Female , Humans
12.
Int J Cancer ; 125(5): 1110-7, 2009 Sep 01.
Article in English | MEDLINE | ID: mdl-19444907

ABSTRACT

Increases in risk of breast cancer in successive generations of migrants to the United States from China and rapid temporal changes in incidence rates in China following social and economic changes clearly implicate environmental factors in the etiology of this disease. Case-control and cohort studies have provided evidence that at least some of these factors may be dietary. Iron, an essential element necessary for cell function, has also been demonstrated to have potential carcinogenic and co-carcinogenic activities. Iron overload, which was previously uncommon, has become more common in the United States than iron deficiency and may be increasing in China concurrently with dramatic increases in meat consumption. A case-control study nested in a cohort of women in Shanghai, China, was conducted to evaluate possible associations between risk of proliferative and nonproliferative fibrocystic changes as well as breast cancer and dietary iron intake and plasma ferritin levels. Plasma ferritin levels and reported dietary iron intake were compared in 346 women with fibrocystic changes, 248 breast cancer cases and 1,040 controls. Increasing ferritin levels were significantly associated with increasing risk of nonproliferative fibrocystic changes (OR: 2.51, 95% CI: 1.16-5.45, p trend = 0.04). Similar, but weaker, trends were observed for proliferative changes and for breast cancer. Risk of breast cancer relative to the risk of fibrocystic changes was associated with dietary iron intake in women with nonproliferative fibrocystic changes (OR: 2.63, 95% CI: 1.04-6.68, p = 0.02). In conclusion, this study finds significant associations between iron (stored and dietary) and fibrocystic disease and breast cancer.


Subject(s)
Breast Neoplasms/epidemiology , Fibrocystic Breast Disease/epidemiology , Iron Compounds/metabolism , Iron, Dietary , Adult , Case-Control Studies , China/epidemiology , Female , Ferritins/blood , Humans , Middle Aged , Risk Factors
13.
Am J Clin Nutr ; 89(1): 265-76, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19056601

ABSTRACT

BACKGROUND: Although benign breast changes are more common than breast cancer, little evidence regarding risk factors for benign breast conditions is available. Omega-3 (n-3) fatty acids have antiinflammatory and antiproliferative actions and may be important in reducing the risk of benign conditions. There is a lack of research on the association of n-3 fatty acids with risk of benign fibrocystic breast changes. OBJECTIVES: The objectives of the study were to evaluate the role of n-3 and other fatty acids in the development of benign proliferative fibrocystic conditions (PFCs) and nonproliferative fibrocystic conditions (NPFCs) in the breast and to evaluate the progression of fibrocystic changes in breast cancer. DESIGN: We conducted a case-control study to determine erythrocyte fatty acid concentrations in 155 women with NPFCs, 185 women with PFCs, 241 women with breast cancer (127 with nonproliferative and 114 with proliferative changes in the noncancerous extratumoral mammary epithelium), and 1,030 control subjects. We estimated the relative risk of NPFCs, PFCs, and breast cancer with proliferative and nonproliferative changes in extratumoral tissue compared with the risk of these changes alone. RESULTS: Women in the highest quartile of eicosapentaenoic acid concentrations were 67% less likely to have an NPFC alone or with breast cancer and 49% less likely to have breast cancer than were women with PFCs. gamma-Linolenic acid (18:3n-6) was positively associated with all fibrocystic and cancerous conditions. Palmitic:palmitoleic acid (n-7 saturation index) was inversely associated with risk in all comparisons. CONCLUSION: Our results support a protective effects of n-3 fatty acid intake and the n-7 saturation index against benign fibrocystic breast changes and the progression of proliferative changes to breast cancer.


Subject(s)
Breast Neoplasms/blood , Diet , Erythrocytes/chemistry , Fatty Acids, Omega-3/administration & dosage , Fatty Acids, Omega-3/analysis , Fibrocystic Breast Disease/blood , Adult , Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Case-Control Studies , China/epidemiology , Female , Fibrocystic Breast Disease/epidemiology , Fibrocystic Breast Disease/pathology , Humans , Middle Aged , Randomized Controlled Trials as Topic , Risk Factors , Young Adult
14.
Cancer Epidemiol Biomarkers Prev ; 16(12): 2579-86, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18086761

ABSTRACT

BACKGROUND: Proliferative benign breast conditions are associated with elevated risk of breast cancer, whereas nonproliferative conditions are not strongly associated with risk. Factors acting before onset of hyperplasia might be associated with both benign conditions and breast cancer, whereas those on the proliferative disease-to-cancer pathway would be associated only with cancer. Soy isoflavone exposure may influence breast cancer risk, but little is known of its association with benign conditions. MATERIALS AND METHODS: We examined possible relationships between plasma genistein and daidzein concentrations and risk of breast disease in women, in a breast self-examination trial in Shanghai, China, diagnosed with breast cancer (n = 196) or a benign breast condition (n = 304), and 1,002 age-matched controls with no known breast disease. Benign conditions were classified as nonproliferative (n = 131) or proliferative with or without atypia (n = 173). RESULTS: Isoflavone concentrations were inversely associated with risk of nonproliferative and proliferative benign fibrocystic conditions, as well as with breast cancer, both with and without concomitant proliferative changes in ipsilateral noncancerous mammary epithelium (P(trend) < 0.01 for all comparisons with controls). Women in the highest quartile of plasma genistein (>76.95 ng/mL) were less likely to have breast cancer (odds ratio, 0.26; 95% confidence interval, 0.13-0.50) or benign conditions (odds ratio, 0.40; 95% confidence interval, 0.23-0.70) compared with women in the lowest quartile (<9.42 ng/mL). Observed risks for breast cancer with and without surrounding proliferative changes were not different, respectively, from observed risks for benign proliferative and nonproliferative conditions alone. CONCLUSION: Isoflavone exposure was inversely associated with fibrocystic breast conditions and breast cancer, and the results suggest that effects on cancer risk occur early in carcinogenesis.


Subject(s)
Breast Neoplasms/blood , Fibrocystic Breast Disease/blood , Genistein/blood , Isoflavones/blood , Adult , Breast Neoplasms/epidemiology , Case-Control Studies , China/epidemiology , Chromatography, Liquid , Diet , Female , Fibrocystic Breast Disease/epidemiology , Humans , Mass Spectrometry , Middle Aged , Randomized Controlled Trials as Topic , Risk Factors , Soybean Proteins
15.
Zhonghua Zhong Liu Za Zhi ; 27(6): 350-4, 2005 Jun.
Article in Chinese | MEDLINE | ID: mdl-16117898

ABSTRACT

OBJECTIVE: A randomized trial of breast self-examination (BSE) program was carried out to evaluate whether the intensive BSE can reduce the death number of women from breast cancer. METHODS: A total of 266,064 women (age of 30 to 64 years) associated with 519 textile factories in Shanghai had been randomly assigned to a BSE instruction group (132,979 women) or a control group (133,085 women) since 1989. Initial instruction in BSE group included demonstration of proper palpation techniques. It was followed by 2 reinforcement sessions during the subsequent 4 years including video shows, BSE instruction sessions and BSE practice under medical supervision. These activities were continued for 5 years. Attendance at all events was recorded. The cohort was followed through July 2000 for development of breast diseases, and the breast cancer cases were followed up through 2001 for vital status. The data analysis methods used included Kaplan-Meier plots, Log-rank test and Cox modeling. RESULTS: Among women under instruction, 864 breast cancers were detected and 133 breast cancer deaths occurred, and 896 breast cancers were detected and 130 deaths recorded in the control group. The tumor size (P = 0.07), TNM stage (P = 0.39) and cumulative breast cancer mortality rate (P = 0.72) were not significantly different between the 2 groups. However, more and smaller fibroadenomas were detected in the instruction group than in the control group (P < 0.01). CONCLUSION: Intensive instruction in BSE can not reduce mortality rate of breast cancer, but more and smaller benign breast lumps can be detected.


Subject(s)
Breast Neoplasms/diagnosis , Breast Neoplasms/prevention & control , Breast Self-Examination , Adult , Breast Neoplasms/epidemiology , China/epidemiology , Female , Humans , Incidence , Mass Screening , Middle Aged
16.
Int J Cancer ; 115(6): 981-93, 2005 Jul 20.
Article in English | MEDLINE | ID: mdl-15723298

ABSTRACT

Risk of breast cancer is increased in women with proliferative benign breast conditions. Most of these conditions, however, do not progress to breast cancer. The purpose of our study was to identify factors possibly associated with this progression. Women with proliferative fibrocystic breast conditions alone (214), and women with proliferative fibrocystic breast conditions and concurrent breast cancer (130), were compared to each other, and each of these groups of women were also compared to 1,070 controls; and 176 women with non-proliferative benign breast conditions alone, and 155 also with breast cancer, were similarly compared. All study subjects were selected from a cohort of women enrolled in a trial of breast self-examination in Shanghai. Women were interviewed to ascertain information on suspected risk factors for breast cancer and dietary habits. Conditional logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). Increased risks of both proliferative fibrocystic breast conditions alone, and with breast cancer, were associated with low parity, a prior benign breast lump and breast cancer in a first-degree relative. Decreasing trends in the risk of both conditions with increasing intake of fruits and vegetables were observed. No factors were significantly associated with risk of breast cancer relative to risk of proliferative changes. Similar, but in some instances weaker, associations were observed for non-proliferative fibrocystic conditions with and without breast cancer. The possible risk or protective factors that were observed in our study most likely alter the risk of breast cancer at an early stage in the carcinogenic process, and probably do not alter risk of progression from proliferative fibrocystic breast conditions to breast cancer.


Subject(s)
Breast Neoplasms/etiology , Diet , Fibrocystic Breast Disease/etiology , Parity , Adult , Breast Neoplasms/complications , Case-Control Studies , China , Disease Progression , Female , Fibrocystic Breast Disease/complications , Fruit , Humans , Maternal Age , Middle Aged , Risk Factors , Vegetables
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