Displaying publications 1 - 20 of 106 in total

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  1. Sharma D, Kumar S, Narasimhan B, Ramasamy K, Lim SM, Shah SAA, et al.
    BMC Chem, 2019 Dec;13(1):60.
    PMID: 31384808 DOI: 10.1186/s13065-019-0575-x
    In order to overcome the challenges of microbial resistance as well as to improve the effectiveness and selectivity of chemotherapeutic agents against cancer, a novel series of 4-(4-bromophenyl)-thiazol-2-amine derivatives was synthesized and its molecular structures were confirmed by physicochemical and spectral characteristics. The synthesized compounds were further evaluated for their in vitro antimicrobial activity using turbidimetric method and anticancer activity against oestrogen receptor positive human breast adenocarcinoma cancer cell line (MCF7) by Sulforhodamine B (SRB) assay. The antimicrobial activity results revealed that compound p2, p3, p4 and p6 exhibited promising antimicrobial activity that are comparable to standard norfloxacin (antibacterial) and fluconazole (antifungal). Anticancer screening results demonstrated that compound p2 was found to be the most active one against cancer cell line when compared to the rest of the compounds and comparable to the standard drug (5-fluorouracil). The molecular docking study demonstrated that compounds, p2, p3, p4 and p6 displayed good docking score within binding pocket of the selected PDB ID (1JIJ, 4WMZ and 3ERT) and showed promising ADME properties.
    Matched MeSH terms: Receptors, Estrogen
  2. Adam SA, Kamaruddin KN, Abd Shukor N, Abdullah Suhaimi SN, Ismail F, Md Yasin M
    Am J Case Rep, 2023 Dec 04;24:e941448.
    PMID: 38048289 DOI: 10.12659/AJCR.941448
    BACKGROUND Breast squamous cell carcinoma (SCC) is a subtype of metaplastic breast carcinoma (MBC), which is a rare malignancy and accounts for 0.1% of all invasive breast carcinomas. Guidelines on definitive management and treatment of breast SCC are not well established, given its rarity and diverse immunohistochemistry (IHC) profile, and lack of clinical data. Most cases of breast SCC are triple-negative breast cancer - negative for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). This case report outlines the clinicopathological profile of a pure breast SCC case with a rare IHC profile; HER2 and ER positive. CASE REPORT A 41-year-old woman presented with a right breast mass that had been growing for 2 months. Biopsy confirmed breast SCC, a rare malignancy with IHC profile as follows: HER2 overexpression, ER positive, and PR negative. She underwent neoadjuvant chemotherapy for 3 months followed by right mastectomy with axillary clearance, adjuvant radiotherapy, and oral tamoxifen therapy. Unfortunately, she did not receive anti-HER2 therapy. She developed early locoregional recurrence at 2 months postoperatively, which was treated with excision of the right chest wall and transverse rectus abdominis musculocutaneous (TRAM) flap. She developed liver and lung metastasis and succumbed to her disease at 15 months post-diagnosis. CONCLUSIONS Breast SCC is a rare and aggressive tumor with heterogeneous clinicopathological features. Available guidelines do not outline the definitive treatment for breast SCC, given its rarity and heterogenous IHC profile, leading to a general lack of clinical data. Hence, due to the challenges in managing this rare condition, treatment modalities need to be individualized.
    Matched MeSH terms: Receptors, Estrogen/metabolism
  3. Abdul Wahab K, Ahmad FB, Din LB, Cheah SH, Mock SL
    Trop Biomed, 2004 Dec;21(2):139-44.
    PMID: 16493406 MyJurnal
    The crude methanol extracts of Gelsemium elegans leaves were assessed for their cytotoxic activity using the microculture 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cellular viability. This study utilized two different types of human cancer cell lines, CaOV-3 (human ovarian cancer cells) and MDA-MB-231 (human estrogen receptor negative breast cancer cells), allowing for comparison of toxicity of G. elegans against these two cancer cells lines. Our results showed that the methanol extract of G. elegans exhibited high cytotoxicity against the human ovarian cancer cell line CaOV-3 with an IC50 value of 5microg/ml after 96 h incubation. However, G. elegans displayed discernibly less toxicity against the MDA-MB-231 cells with an IC50 value 40microg/ml after 96 h incubation and this effect was dose- and time-dependent, up to 72h and 20-30 microg/ml. In conclusion, our results demonstrated that G. elegans is potently cytotoxic against the human ovarian cancer cell line CaOV-3 and to a lesser extend towards the human breast carcinoma cancer MDA-MB-231 cells, suggesting that the extract is selective towards CaOV-3 cells and may have a chemotherapeutic role for ovarian cancer treatment in the future.
    Matched MeSH terms: Receptors, Estrogen
  4. Chajès V, Assi N, Biessy C, Ferrari P, Rinaldi S, Slimani N, et al.
    Ann Oncol, 2017 Nov 01;28(11):2836-2842.
    PMID: 28950350 DOI: 10.1093/annonc/mdx482
    BACKGROUND: Intakes of specific fatty acids have been postulated to impact breast cancer risk but epidemiological data based on dietary questionnaires remain conflicting.

    MATERIALS AND METHODS: We assessed the association between plasma phospholipid fatty acids and breast cancer risk in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition study. Sixty fatty acids were measured by gas chromatography in pre-diagnostic plasma phospholipids from 2982 incident breast cancer cases matched to 2982 controls. Conditional logistic regression models were used to estimate relative risk of breast cancer by fatty acid level. The false discovery rate (q values) was computed to control for multiple comparisons. Subgroup analyses were carried out by estrogen receptor (ER) and progesterone receptor expression in the tumours.

    RESULTS: A high level of palmitoleic acid [odds ratio (OR) for the highest quartile compared with the lowest OR (Q4-Q1) 1.37; 95% confidence interval (CI), 1.14-1.64; P for trend = 0.0001, q value = 0.004] as well as a high desaturation index (DI16) (16:1n-7/16:0) [OR (Q4-Q1), 1.28; 95% C, 1.07-1.54; P for trend = 0.002, q value = 0.037], as biomarkers of de novo lipogenesis, were significantly associated with increased risk of breast cancer. Levels of industrial trans-fatty acids were positively associated with ER-negative tumours [OR for the highest tertile compared with the lowest (T3-T1)=2.01; 95% CI, 1.03-3.90; P for trend = 0.047], whereas no association was found for ER-positive tumours (P-heterogeneity =0.01). No significant association was found between n-3 polyunsaturated fatty acids and breast cancer risk, overall or by hormonal receptor.

    CONCLUSION: These findings suggest that increased de novo lipogenesis, acting through increased synthesis of palmitoleic acid, could be a relevant metabolic pathway for breast tumourigenesis. Dietary trans-fatty acids derived from industrial processes may specifically increase ER-negative breast cancer risk.

    Matched MeSH terms: Receptors, Estrogen/metabolism
  5. Yip CH, Bhoo Pathy N, Teo SH
    Med J Malaysia, 2014 Aug;69 Suppl A:8-22.
    PMID: 25417947 MyJurnal
    Four hundred and nineteen articles related to breast cancer were found in a search through a database dedicated to indexing all original data relevant to medicine published in Malaysia between the years 2000-2013. One hundred and fifty four articles were selected and reviewed on the basis of clinical relevance and future research implications. Overall, Malaysian women have poor survival from breast cancer and it is estimated that half of the deaths due to breast cancer could be prevented. Five-year survival in Malaysia was low and varies among different institutions even within the same disease stage, suggesting an inequity of access to optimal treatment or a lack of compliance to optimal treatment. Malaysian women have poor knowledge of the risk factors, symptoms and methods for early detection of breast cancer, leading to late presentation. Moreover, Malaysian women experience cancer fatalism, belief in alternative medicine, and lack of autonomy in decision making resulting in delays in seeking or avoidance of evidence-based medicine. There are ethnic differences in estrogen receptor status, HER2 overexpression and incidence of triple negative breast cancer which warrant further investigation. Malay women present with larger tumours and at later stages, and even after adjustment for these and other prognostic factors (stage, pathology and treatment), Malay women have a poorer survival. Although the factors responsible for these ethnic differences have not been elucidated, it is thought that pharmacogenomics, lifestyle factors (such as weight-gain, diet and exercise), and psychosocial factors (such as acceptance of 2nd or 3rd line chemotherapy) may be responsible for the difference in survival. Notably, survivorship studies show self-management programmes and exercise improve quality of life, highlighting the need to evaluate the psychosocial impact of breast cancer on Malaysian women, and to design culturally-, religiously- and linguistically-appropriate psycho-education programmes to help women cope with the disease and improve their quality of life. Research done in the Caucasian populations may not necessarily apply to local settings and it is important to embark on local studies particularly prevention, screening, diagnostic, prognostic, therapeutic and psychosocial research.
    Matched MeSH terms: Receptors, Estrogen
  6. Teoh KH, Looi LM, Sabaratnam S, Cheah PL, Nazarina AR, Mun KS
    Malays J Pathol, 2011 Jun;33(1):35-42.
    PMID: 21874750 MyJurnal
    Predictive biomarkers such as oestrogen (ER) and progesterone (PR) receptors and c-erbB-2 oncoprotein have become a staple in breast cancer reports in the country as they increasingly play an important role in the treatment and prognosis of women with breast cancers. This study reviews the practice of histopathology reporting of these biomarkers in a Malaysian tertiary hospital setting. Retrospective data on demographic, pathological and biomarker profiles of patients with invasive ductal carcinoma who had undergone mastectomy or lumpectomy with axillary node clearance from 2005 to 2006 were retrieved from the Department of Pathology, Penang Hospital and analysed. The prevalence of ER positivity (55.8%), PR positivity (52.5%), c-erbB-2 oncoprotein overexpression (24%) and triple negativity (ER negative, PR negative, c-erbB-2 negative) (15%) by immunohistochemistry were comparable with other studies. Notably, c-erbB-2 overexpression was equivocal (2+) in 15% of cases. Since about a quarter of equivocal (2+) cases usually show amplification by FISH, a small but certain percentage of patients would miss the benefit of anti-c-erbB-2 antibody therapy if FISH is not performed. New ASCO/CAP guidelines on the quantitation of ER and PR will probably increase the prevalence of ER/PR positivity, invariably leading to significant ramifications on the management of patients as more patients would be deemed eligible for endocrine therapy, as well as categorisation of triple negative breast cancers.
    Matched MeSH terms: Receptors, Estrogen/biosynthesis; Receptors, Estrogen/genetics
  7. Naidu R, Har YC, Taib NA
    Scand J Clin Lab Invest, 2011 Oct;71(6):500-6.
    PMID: 21745146 DOI: 10.3109/00365513.2011.590223
    The purpose of this study was to investigate the association between the peptidyl-propyl-cis/trans isomerase 1 (PIN1) -842(G > C) and -667(T > C) polymorphic variants and breast cancer risk among Malaysian ethnic groups namely the Malays, Chinese and Indians, as well as clinico-pathological characteristics of the patients.
    Matched MeSH terms: Receptors, Estrogen/metabolism
  8. Rajaratinam H, Nafi SNM
    Malays J Med Sci, 2019 Sep;26(5):6-20.
    PMID: 31728115 MyJurnal DOI: 10.21315/mjms2019.26.5.2
    Oestrogen receptor (ER)-positive breast cancer is one of the common forms of breast cancer affecting women worldwide. ER-positive breast cancer patients are subjected to anti-oestrogen therapy such as selective oestrogen receptor modulator (SERM) and aromatase inhibitors (AIs). Recently, the emergence of resistance to anti-oestrogen treatment is under intensive focus. The different mechanisms postulated to explain the occurrence of resistance in ER-positive breast cancer treatment include the loss of ER function and the crosstalk between signalling pathways in cancer cells. Recent literature highlighted that the cholesterol biosynthesis pathway acts as a novel mechanism underlying resistance to oestrogen deprivation. The present study aimed to highlight the role of cholesterol biosynthesis in anti-oestrogen treatment resistance, putatively suggesting an alternative plant-based treatment using andrographolide from Andrographis paniculata. The hypolipidaemic effect of andrographolide can be utilised to prevent the resistance in the treatment of ER-positive breast cancer contributed by cholesterol biosynthesis.
    Matched MeSH terms: Receptors, Estrogen
  9. Hashim NM, Rahmani M, Ee GC, Sukari MA, Yahayu M, Oktima W, et al.
    J Biomed Biotechnol, 2012;2012:130627.
    PMID: 21960741 DOI: 10.1155/2012/130627
    An investigation of the chemical constituents in Artocarpus obtusus species led to the isolation of three new xanthones, pyranocycloartobiloxanthone A (1), dihydroartoindonesianin C (2), and pyranocycloartobiloxanthone B (3). The compounds were subjected to antiproliferative assay against human promyelocytic leukemia (HL60), human chronic myeloid leukemia (K562), and human estrogen receptor (ER+) positive breast cancer (MCF7) cell lines. Pyranocycloartobiloxanthone A (1) consistently showed strong cytotoxic activity against the three cell lines compared to the other two with IC(50) values of 0.5, 2.0 and 5.0 μg/mL, respectively. Compound (1) was also observed to exert antiproliferative activity and apoptotic promoter towards HL60 and MCF7 cell lines at respective IC(50) values. The compound (1) was not toxic towards normal cell lines human nontumorigenic breast cell line (MCF10A) and human peripheral blood mononuclear cells (PBMCs) with IC(50) values of more than 30 μg/mL.
    Matched MeSH terms: Receptors, Estrogen/analysis
  10. Kamil M, Khalid I, Hashim H, Biswas M, Kaur G, Islam R
    J Coll Physicians Surg Pak, 2010 Apr;20(4):250-2.
    PMID: 20392401 DOI: 04.2010/JCPSP.250252
    To determine the association between histological grade of tumour and estrogen progesterone receptors (ER/PR) expression in unselected invasive carcinoma of breast in Malaysian patients.
    Matched MeSH terms: Receptors, Estrogen/biosynthesis*; Receptors, Estrogen/genetics
  11. Al-Joudi, Fawwaz S., Iskandar Zulkarnain A.
    MyJurnal
    Bcl-2 is an anti-apoptotic protein belonging to a family of proteins that act as regulators of apoptosis in mammalian cells. Bcl-2 expression has previously been reported in normal breast ductal cells and its involvement in the hormonal regulation of hyperplasia and involution was further suggested, and it was thought to be expressed through hormonedependent pathways. Bcl-2 is a cytoplasmic oncoprotein which is highly expressed in human solid tumours. In breast cancer cells, however, Bcl-2 expression is down regulated, the exact mechanism and the effects of which are not clearly defined, as bcl-2 expression appears to be inversely correlated with the presence of p53 mutations. This work aimed at investigating the expression of bcl-2 in invasive ductal carcinoma of the breast utilizing an immunohistochemistry assay as well as studying the clinical correlations of bcl-2. Bcl-2 was detected in 43.7% of 382 invasive ductal carcinoma study cases. Its expression correlated positively, with lower age of patients, higher histological grades, large tumour sizes, estrogen receptor positivity and progesterone receptor negativity. However, the statistical correlations were weak. With the data obtained, it was found that the expression of bcl-2 correlated with unfavourable prognoses. Furthermore, bcl-2 detection alone may not be very helpful in consolidating a clinical diagnosis.







    59-64

    Matched MeSH terms: Receptors, Estrogen
  12. Subramaniam S, Bhoo-Pathy N, Taib NA, Tan GH, See MH, Jamaris S, et al.
    World J Surg, 2015 Oct;39(10):2450-8.
    PMID: 26138872 DOI: 10.1007/s00268-015-3133-2
    Breast cancer can be divided into four subtypes based on the expressions of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor-2 (HER2). Each subtype has different clinicopathological features and outcomes.
    Matched MeSH terms: Receptors, Estrogen/metabolism
  13. Rhodes A, Teoh KH, See MH, Ganesan K, Looi LM
    Pathology, 2020 Apr;52(3):385-387.
    PMID: 32107079 DOI: 10.1016/j.pathol.2019.12.006
    Matched MeSH terms: Receptors, Estrogen/analysis*
  14. Leong BD, Chuah JA, Kumar VM, Yip CH
    Asian Pac J Cancer Prev, 2007 Oct-Dec;8(4):525-9.
    PMID: 18260722
    INTRODUCTION: Malaysian women have a 1 in 20 chance of developing breast cancer in their lifetime. Sabah, formerly known as North Borneo, is part of East Malaysia with a population of 3.39 million and more than 30 ethnic groups. We conducted a 2 year prospective epidemiological study to provide unreported data of breast cancer from this part of the world and to recognise which particular group of patients are more likely to present with advanced disease.

    METHODS: All newly diagnosed breast cancers seen at the Queen Elizabeth Hospital, Kota Kinabalu, from January 2005 to December 2006 were included in the study. Patient and tumour characteristics, including age, race, education, socioeconomic background, parity, practice of breast feeding, hormonal medication intake, menopausal status, family history, mode of presentation, histology, grade, stage of disease and hormonal receptors status were collected and analysed.

    RESULTS: A total of 186 patients were seen. The commonest age group was 40 to 49 years old (32.3%). Chinese was the commonest race (30.6%) followed by Kadazan-Dusun (24.2%). The commonest histology was invasive ductal carcinoma (88.4%). Stages at presentation were Stage 0- 4.8%, Stage I- 12.9%, Stage II- 30.1%, Stage III- 36.6% and Stage IV- 15.6%. The estrogen and progesterone receptor status was positive in 59.1% and 54.8% of cases, respectively. 73.7% of Chinese patients presented with early cancer compared to 36.4% of the other races. Patients who presented with advanced disease were also poor, non-educated and from rural areas. 20.4% of patients defaulted treatment; most of them opted for traditional alternatives.

    CONCLUSIONS: Sabahan women with breast cancer present late. Great efforts are needed to improve public awareness of breast cancer, especially among those who have higher risk of presenting with advanced disease.
    Matched MeSH terms: Receptors, Estrogen/metabolism
  15. Abubakar M, Sung H, Bcr D, Guida J, Tang TS, Pfeiffer RM, et al.
    Breast Cancer Res, 2018 09 18;20(1):114.
    PMID: 30227867 DOI: 10.1186/s13058-018-1033-8
    BACKGROUND: Limited evidence, mostly from studies in Western populations, suggests that the prognostic effects of lifestyle-related risk factors may be molecular subtype-dependent. Here, we examined whether pre-diagnostic lifestyle-related risk factors for breast cancer are associated with clinical outcomes by molecular subtype among patients from an understudied Asian population.

    METHODS: In this population-based case series, we evaluated breast cancer risk factors in relation to 10-year all-cause mortality (ACM) and 5-year recurrence by molecular subtype among 3012 women with invasive breast cancer in Sarawak, Malaysia. A total of 579 deaths and 314 recurrence events occurred during a median follow-up period of ~ 24 months. Subtypes (luminal A-like, luminal B-like, HER2-enriched, triple-negative) were defined using immunohistochemical markers for hormone receptors and human epidermal growth factor receptor 2 (HER2) in conjunction with histologic grade. Hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between risk factors and ACM/recurrence were estimated in subtype-specific Cox regression models.

    RESULTS: We observed heterogeneity in the relationships between parity/breastfeeding, age at first full-term pregnancy (FFP), family history, body mass index (BMI), and tumor subtype (p value  30 vs 

    Matched MeSH terms: Receptors, Estrogen/metabolism
  16. Fernandopulle SM, Cher-Siangang P, Tan PH
    Pathology, 2006 Jun;38(3):219-22.
    PMID: 16753742
    To document the pathological features of breast carcinoma diagnosed in women aged 35 years or less.
    Matched MeSH terms: Receptors, Estrogen/analysis
  17. Looi LM, Cheah PL
    Malays J Pathol, 1998 Jun;20(1):19-23.
    PMID: 10879259
    Eighty-six infiltrating ductal carcinoma of breast were studied by the standard avidin-biotin complex immunoperoxidase method on formalin-fixed, paraffin-embedded tissue sections, for oestrogen receptor (ER) protein and c-erbB-2 oncoprotein expression. They were categorized according to the modified Bloom and Richardson criteria into three histological grades. 21% tumours were ER positive while 44% were c-erbB-2 positive. Of ER positive tumours, 33.3% were c-erbB-2 positive whereas the c-erbB-2 positivity rate was much higher (47.1%) in ER negative tumours. Only 16% of c-erbB-2 positive tumours were ER positive while 25% of c-erbB-2 negative tumours were ER positive. This negative relationship between ER and c-erbB-2 expression was statistically significant (Mc Nemar's test, p < 0.005). The ER positivity rate did not vary significantly with histological grade. However, c-erbB-2 overexpression was significantly more prevalent in grade III tumours compared with grade I and II tumours (Chi-square test, p < 0.005). Since the c-erbB-2 oncogene has extensive structural homology to the epidermal growth factor receptor (EGFR) gene, we expect that c-erbB-2 oncoprotein would share functional similarities with EGFR leading to both loss of oestrogen receptor and poor prognosis in breast cancer. Its overexpression can be expected to relate to more aggressive tumour proliferation and may explain its correlation with high histological grade, a known indicator of aggressive cancer behaviour. As there is no indication that ER protein activity contributes to advancement in histological grade, it would appear that cellular dedifferentiation precedes ER loss during malignant transformation. It has been mooted that ER positive breast cancers which also show c-erbB-2 oncoprotein overexpression have a poorer response to hormonal therapy. The use of this parameter in the routine assessment of breast cancer patients may identify subsets of patients for more aggressive therapy.
    Matched MeSH terms: Receptors, Estrogen/metabolism*
  18. Chin KY, Ima-Nirwana S
    Curr Drug Targets, 2013 Dec;14(14):1632-41.
    PMID: 24354587
    The Asian population whose soy intake is higher compared to Western populations shows a significantly lower incidence of osteoporotic fracture. Several meta-analyses have revealed that supplementation of soy isoflavones improve bone health status in women. This review examined the current evidence as to whether soy could exhibit similar bone protective effects on the male population. In vivo studies revealed that supplementation of soy protein or soy isoflavones improved bone health in both normal and osteoporotic male rodents. Cell culture studies showed that soy isoflavones influenced osteogenesis and osteoclastogenesis through mechanisms such as estrogen receptor binding activity, antiinflammatory activity and anti-parathyroid hormone activity. Soy isoflavones also affected calcium channel signaling and might exhibit direct effects on the osteoblastogenesis modulator, core binding factor 1. However, limited clinical trials involving soy intervention in males generally showed insignificant results. This could be attributed to the short duration of intervention, characteristics of the subjects or method of bone health assessment. More well-planned clinical trials are required to establish possible bone protective effects of soy in men.
    Matched MeSH terms: Receptors, Estrogen/metabolism
  19. Kwan TK, Thambyrajah V
    Med J Malaysia, 1978 Mar;32(3):236-41.
    PMID: 683049
    Matched MeSH terms: Receptors, Estrogen/isolation & purification; Receptors, Estrogen/metabolism*
  20. Ch'ng ES, Tuan Sharif SE, Jaafar H
    Asian Pac J Cancer Prev, 2012;13(9):4445-52.
    PMID: 23167359
    BACKGROUND: Prognosis of breast cancer depends on classic pathological factors and also tumor angiogenesis. This study aimed to evaluate the clinicopathological factors of breast cancer in a tertiary centre with a focus on the relationship between tumor angiogenesis and clinicopathological factors.

    METHODS: Clinicopathological data were retrieved from the archived formal pathology reports for surgical specimens diagnosed as invasive ductal carcinoma, NOS. Microvessels were immunohistochemically stained with anti-CD34 antibody and quantified as microvessel density.

    RESULTS: At least 50% of 94 cases of invasive breast ductal carcinoma in the study were advanced stage. The majority had poor prognosis factors such as tumor size larger than 50mm (48.9%), positive lymph node metastasis (60.6%), and tumor grade III (52.1%). Higher percentages of estrogen and progesterone receptor negative cases were recorded (46.8% and 46.8% respectively). Her-2 overexpression cases and triple negative breast cancers constituted 24.5% and 22.3% respectively. Significantly higher microvessel density was observed in the younger patient age group (p=0.012). There were no significant associations between microvessel density and other clinicopathological factors (p>0.05).

    CONCLUSIONS: Majority of the breast cancer patients of this institution had advanced stage disease with poorer prognostic factors as compared to other local and western studies. Breast cancer in younger patients might be more proangiogenic.

    Matched MeSH terms: Receptors, Estrogen/metabolism
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