Displaying publications 1 - 20 of 42 in total

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  1. Jayaranee S, Sthaneshwar P
    Int J Lab Hematol, 2010 Oct;32(5):512-8.
    PMID: 20109166 DOI: 10.1111/j.1751-553X.2009.01215.x
    We evaluated the usefulness of RET-Y and RBC-Y in distinguishing functional iron deficiency from iron-deficiency anaemia (IDA) in patients with anaemia of inflammation (AI). Sixty healthy blood donors constituted the control group. We studied RET-Y and RBC-Y in 115 patients with hypochromic/microcytic anaemia. Of these 42 patients had uncomplicated IDA and 73 had AI. The AI patients were further subdivided into AI with IDA and AI with functional IDA based on soluble transferrin receptor (sTfR) levels. The mean RBC-Y and RET-Y values in iron-deficient patients were 122.4 and 119.8, respectively, which were significantly lower than the control (P < 0.001). The mean level of RET-Y in patients with AI associated with IDA was 149.3 and this level in AI patients with functional iron deficiency was 147.4. RET-Y levels in both subgroups of AI patients were significantly lower than control but no significant difference was observed between the two subgroups. Similar findings were observed for RBC-Y. Receiver operating characteristic analysis also showed lower specificity for RBC-Y and RET-Y compared with that of sTfR and its log ferritin ratio (F-index). RET-Y and RBC-Y are useful in the diagnosis of simple IDA but have limited utility in the diagnosis of IDA with AI.
  2. Jayaranee S, Sthaneshwar P
    Singapore Med J, 2006 Feb;47(2):138-42.
    PMID: 16435056
    The objective of this study was to assess the clinical significance of soluble transferrin receptor (sTfR) in hypochromic microcytic anaemia.
  3. Sthaneshwar P, Chan SP
    Malays J Pathol, 2010 Jun;32(1):43-7.
    PMID: 20614725 MyJurnal
    Type IV collagen is the principal component of glomerular basement membrane and messangial matrix. Studies have shown increased levels of urinary type IV collagen (uIV) in diabetic patients compared to healthy controls. The concentration of uIV increases gradually as diabetic nephropathy progresses.
    AIM AND METHOD: This study was carried out to determine whether urinary type IV collagen (uIV) can serve as an indicator of diabetic nephropathy. Using a sandwich enzyme immunoassay technique, uIV excretion was determined in 30 type 2 diabetic patients with normoalbuminuria and 20 patients with microalbuminuria.
    RESULTS: uIV excretion was significantly increased in type 2 diabetics, in both normoalbuminuric and microalbuminuric patients, compared with healthy controls. The increase in urinary type IV collagen was well correlated with the amount of urinary albumin but not with HbA1C.
    CONCLUSION: Our findings that uIV is higher in those with microalbuminuria and correlates with albuminuria, support uIV as an indicator of diabetic nephropathy. Whether the increased uIV excretion would predict the impending renal failure needs further confirmation.
  4. Jayaram G, Sthaneshwar P
    Diagn Cytopathol, 2002 Apr;26(4):222-7.
    PMID: 11933267
    Breast lesions with a significant spindle cell or mesenchymal component are not commonly encountered in fine-needle aspiration (FNA) cytologic material and include a heterologous variety of benign and malignant conditions, with phyllodes tumors (PTs) being the foremost differential diagnostic consideration. This study comprises 28 tumors diagnosed histologically as PT in which FNAC material was available for review. Histological sections and cytological smears from these cases were retrieved and subjected to detailed morphological review. Cytological parameters assessed included ratio of stroma to epithelium, pattern characteristics and cytological characteristics of the stromal, and epithelial components and the background cells. Large and hypercellular stroma fragments, dissociated spindle and plump stromal cells, often accompanied by large, folded sheets of epithelium were cytological features that characterized PT. Smears from malignant PT showed predominantly or solely mesenchymal components. FNAC was a highly reliable procedure for the diagnosis of PT, giving an accuracy rate of 92.8%.
  5. Mohamed Zainuddin N, Sthaneshwar P, Ratnasingam J
    Malays J Pathol, 2020 Aug;42(2):203-207.
    PMID: 32860372
    INTRODUCTION: Phaeochromocytoma may present with uncontrolled hypertension leading to haemorrhagic stroke (HS), ischaemic stroke (IS) and transient ischaemic attack (TIA). False elevation in the levels of CATS/ METS has been reported in acute cerebrovascular disease. Our aim was to analyse the frequency and pattern of elevations of CATS/METS in patients with acute cerebrovascular disease and to determine associated factors.

    MATERIALS AND METHODS: This is a retrospective study of 112 samples of CATS/ METS received by the laboratory over a two-year period, from patients with acute cerebrovascular disease. CATS/METS were measured using LC/MS/MS method. Clinical details and CATS/METS level were obtained from the database. Mann-Whitney U test and Kruskal Wallis test were used for statistical analysis. These statistical analyses were performed using SPSS v.20.0 (IBM Corp., Armonk, NY, USA).

    RESULTS: Of the 112 patients, 39% had HS, 54% had IS and 7% had TIA. A total of 29% of patients had elevated CATS/ METS. Elevated levels of CATS/METS were noted in 41% and 25% of HS and IS patients, respectively (p=0.53). Median norepinephrine, epinephrine and metanephrine levels in HS were significantly higher than IS (p< 0.05). Systolic blood pressure was higher in those who had elevated CATS/ METS (p=0.04). Only for two patients with elevated CATS/METS repeat testing was performed. Age, diastolic blood pressure and the time of sample collection in relation to the presentation, for CATS/METS were not significantly different between groups that had elevated levels of CATS/ METS versus those who did not.

    CONCLUSION: We noted that CATS/METS were elevated in one-third of patients, especially in patients with high systolic blood pressure. Increase in CATS/METS should be appropriately followed up with repeat testing. Since false elevation in CATS/METS has been reported in cerebrovascular disease, screening for phaeochromocytoma is best deferred for a month.

  6. Nadarajan VS, Sthaneshwar P, Jayaranee S
    Int J Lab Hematol, 2010 Apr;32(2):215-21.
    PMID: 19566741 DOI: 10.1111/j.1751-553X.2009.01174.x
    Individuals with alpha-thalassaemia (ATT), beta-thalassaemia (BTT) and HbE trait (HET) are often initially identified based on haematological parameters. However, the values of these parameters usually overlap with iron deficiency anaemia (IDA) and anaemia of chronic disease (ACD). We evaluated the use of RBC-Y in 156 normal individuals and 332 patients; ATT (n = 37), BTT (n = 61), HET (n = 25), HbH disease (n = 5), ACD (n = 67), IDA (n = 83) and ACD with IDA (n = 54). Diagnostic efficiency was analysed by receiver operating characteristics (ROC). MCH was better compared with RBC-Y in discriminating normal from abnormal with sensitivity and specificity of 94% at a cut-off of 26 pg. The Green and King (G&K) index performed the best in discriminating carriers from IDA and ACD with area under the ROC curve (AUC(ROC)) of 0.81. However, if ACD was excluded, RBC-Y/MCV was a good discriminator for carriers from IDA with AUC(ROC) = 0.845. In general screening of populations with ATT, BTT and HET, we propose that hypochromic individuals be first identified by MCH <26 pg and carriers distinguished within these hypochromic individuals from IDA by using RBC-Y/MCV. However, if the prevalence of ACD were high within the screening population, G&K index would be a more suitable discriminator.
  7. Nadarajan V, Sthaneshwar P, Eow GI
    Transfus Med, 2008 Jun;18(3):184-9.
    PMID: 18598281 DOI: 10.1111/j.1365-3148.2008.00862.x
    The objective of this study was to identify haematological parameters useful in screening for iron deficiency among blood donors. Iron deficiency is a common complication of blood donation and often goes unrecognized until anaemia develops. Biochemical markers such as soluble transferrin receptor (TfR), ferritin and log(TfR/F) have been proposed as more valid indicators of body iron status. Red blood cell (RBC) parameters are, however, more easily measured and have also been proposed as indicators of iron depletion. We measured ferritin and TfR in 192 blood donors together with RBC analysis, performed on two haematology analysers. Thirteen donors had parameters suggestive of haemoglobinopathy and were excluded from further analysis. Overall, 10% (18/179) of the remaining donors had iron deficiency, as defined by log(TfR/F) exceeding the 95th percentile of the value in the population of first-time donors. Using receiver operating characteristic analysis, the sensitivity of ferritin was 100%, with a specificity of 90% at a cut-off of 15 mug L(-1). The sensitivity and specificity of RBC-Y at a cut-off of 152 for detecting iron deficiency were 81 and 89%, respectively. Haemoglobin content of reticulocytes, meanwhile, showed sensitivity of 69% and specificity of 93% when a cut-off of 28 pg was used. Both measures compare favourably with haemoglobin which only showed a sensitivity of 50%, although specificity was 91% at a cut-off value of 125 g L(-1). The parameter RBC-Y can be useful as a screening measure for iron deficiency in blood donors.
  8. Jayaranee S, Sthaneshwar P, Sokkalingam S
    Pathology, 2009 Feb;41(2):178-82.
    PMID: 18972320 DOI: 10.1080/00313020802436840
    AIM: Hepcidin, a recently identified peptide, acts as a central regulator of iron metabolism. It is regarded as a factor regulating the uptake of dietary iron and its mobilisation from macrophages and hepatic stores. It is considered as a mediator of anaemia of inflammation. The aim of this study was to assess whether serum prohepcidin concentration is able to distinguish iron deficiency from anaemia of inflammation in patients with rheumatoid arthritis (RA).

    METHOD: Blood samples were obtained from 20 healthy blood donors, 30 RA patients who presented with anaemia and 30 patients who had pure iron deficiency anaemia (IDA). The samples were analysed for full blood count, iron, ferritin, transferrin, soluble transferrin receptor and prohepcidin.

    RESULTS: The mean prohepcidin level in the control subjects was 256 microg/L. The prohepcidin level was significantly lower in IDA patients (100 microg/L; p < 0.0001) but not significantly different from that of control in RA patients (250 microg/L; p > 0.05). Higher serum soluble transferrin receptor (sTfR) levels were observed in IDA (p < 0.0001) but not in RA compared with that of control (p > 0.05). RA patients were divided into iron depleted and iron repleted subgroups based on the ferritin level. Prohepcidin in the iron depleted group was significantly lower than the iron repleted group and the control (p < 0.0001) and higher levels were observed in the iron repleted group (p < 0.01). sTfR levels in the iron depleted group were significantly higher than the control and the iron repleted patients (p < 0.001). In the iron repleted group, sTfR level was not statistically different from that of control (p > 0.05).

    CONCLUSION: Serum prohepcidin is clearly reduced in uncomplicated iron deficiency anaemia. The reduced prohepcidin levels in the iron depleted RA patients suggests that there may be conflicting signals regulating hepcidin production in RA patients. In RA patients who have reduced hepcidin in the iron depleted group (ferritin <60 microg/L) where sTfR levels are increased suggests that these patients are iron deficient. Further studies with a larger cohort of patients are required to substantiate this point.

  9. Nadaraja RND, Sthaneshwar P, Razali N
    Malays J Pathol, 2018 Apr;40(1):33-39.
    PMID: 29704382 MyJurnal
    INTRODUCTION: Hyperandrogenism remains as one of the key features in Polycystic Ovarian Syndrome (PCOS) and can be assessed clinically or determined by biochemical assays. Hirsutism is the most common clinical manifestation of hyperandrogenism. The clinical assessment is subjected to wide variability due to poor interobserver agreement and multiple population factors such as ethnic variation, cosmetic procedures and genetic trait. The difficulty in resolving the androgen excess biochemically is due to a lack of consensus as to which serum androgen should be measured for the diagnosis of PCOS. The aim of the study was to compare and establish the diagnostic cut off value for different androgen biomarker for the diagnosis of PCOS.

    MATERIALS AND METHODS: A total of 312 patients classified to PCOS (n = 164) and non PCOS (n = 148) cohorts were selected from the Laboratory Information System (LIS) based on serum total testosterone (TT) and sex hormone binding globulin (SHBG) from the period of 1st April 2015 to 31st March 2016. PCOS was diagnosed based on Rotterdam criteria. Clinical hyperandrogenism and ultrasound polycystic ovarian morphology were obtained from the clinical records. The other relevant biochemical results such as serum luteinizing hormone (LH), follicle stimulating hormone (FSH) and albumin were also obtained from LIS. Free androgen index (FAI), calculated free testosterone (cFT) and calculated bioavailable testosterone (cBT) were calculated for these patients. Receiver Operating Characteristic (ROC) curve analysis were performed for serum TT, SHBG, FAI, cFT, cBT and LH: FSH ratio to determine the best marker to diagnose PCOS.

    RESULTS: All the androgen parameters (except SHBG) were significantly higher in PCOS patients than in control (p<0.0001). The highest area under curve (AUC) curve was found for cBT followed by cFT and FAI. TT and LH: FSH ratio recorded a lower AUC and the lowest AUC was seen for SHBG. cBT at a cut off value of 0.86 nmol/L had the highest specificity, 83% and positive likelihood ratio (LR) at 3.79. This is followed by FAI at a cut off value of 7.1% with specificity at 82% and cFT at a cut off value of 0.8 pmol/L with specificity at 80%. All three calculated androgen indices (FAI, cFT and cBT) showed good correlation with each other. Furthermore, cFT, FAI and calculated BT were shown to be more specific with higher positive likelihood ratio than measured androgen markers.

    CONCLUSIONS: Based on our study, the calculated testosterone indices such as FAI, cBT and cFT are useful markers to distinguish PCOS from non-PCOS. Owing to ease of calculation, FAI can be incorporated in LIS and can be reported with TT and SHBG. This will be helpful for clinician to diagnose hyperandrogenism in PCOS.

  10. Zakaria NH, Sthaneshwar P, Shanmugam H
    Malays J Pathol, 2017 Dec;39(3):317-320.
    PMID: 29279597 MyJurnal
    Hypophosphataemia is a metabolic disorder that is commonly encountered in critically ill patients. Phosphate has many roles in physiological functions, thus the depletion of serum phosphate could lead to impairment in multiple organ systems, which include the respiratory, cardiovascular, neurological and muscular systems and haematological and metabolic functions. Hypophosphataemia is defined as plasma phosphate level below 0.80 mmol per litre (mmol/L) and can be further divided into subgroups of mild (plasma phosphate of 0.66 to 0.79 mmol/L), moderate (plasma phosphate of 0.32 to 0.65 mmol/L) and severe (plasma phosphate of less than 0.32 mmol/L). The causes of hypophosphataemia include inadequate phosphate intake, decreased intestinal absorption, gastrointestinal or renal phosphate loss, and redistribution of phosphate into cells. Symptomatic hypophosphataemia associated with haematological malignancies has been reported infrequently. We report here a case of asymptomatic severe hypophosphataemia in a child with acute T-cell lymphoblastic leukaemia. A 14-year-old Chinese boy was diagnosed to have acute T cell lymphoblastic leukaemia (ALL). His serum biochemistry results were normal except inorganic phosphate and lactate dehydrogenase levels. The serum inorganic phosphate level was 0.1mmol/L and the level was low on repeated analysis. The child had no symptoms related to low phosphate levels. The possible causes of low phosphate were ruled out and urine Tmp/GFR was normal. Chemotherapy regime was started and the serum phosphate levels started to increase. Hypophosphataemia in leukaemia was attributed to shift of phosphorus into leukemic cells and excessive cellular phosphate consumption by rapidly proliferating cells. Several reports of symptomatic hypophosphataemia in myelogenous and lymphoblastic leukaemia in adults have been reported. To our knowledge this is the first case of severe asymptomatic hypophosphataemia in a child with ALL.
  11. Sthaneshwar P, Vethakkan SR, Wong CW
    Med J Malaysia, 2014 Aug;69(4):175-7.
    PMID: 25500845 MyJurnal
    INTRODUCTION: Glycohemoglobin (HbA1c) most accurately reflects the previous two to three months of glycaemic control. HbA1c should be measured regularly in all patients with diabetes, and values should be maintained below 7% to prevent the risk of chronic complications. Apart from the genetic variants of haemoglobins many other conditions also known to affect HbA1c measurements. In this study we evaluated the conditions that cause low HbA1c results.

    METHODS AND MATERIALS: The data was collected retrospectively HbA1c was measured in our laboratory by Biorad Variant II turbo 2.0. The method is based on chromatographic separation of HbA1c on a cation exchange cartridge. This method has been certified by National Glycohemoglobin Standardization Programme (NGSP). 58437 requests were received in a period of one year (January to December 2011). Medical records were reviewed to identify the conditions that might be associated with these low values.

    RESULTS: Among 58437 samples analysed, 53 patients had HbA1c levels < 4.0%. Fourteen patients had haemoglobinopathy. In 34 patients without Hb variants had conditions such as chronic liver disease, chronic kidney disease, haemolytic anaemia, pregnancy, and anaemia of chronic disease. Five non-pregnant individuals who were screened for diabetes mellitus had HbA1c levels < 4%.

    CONCLUSION: Our study underscores the importance of that both laboratories and the physicians should be aware of the factors that can influence the HbA1c results. The haematological status should be taken into consideration for proper interpretation of HbA1c results.
  12. Sockalingam S, Chow SK, Sthaneshwar P
    Int J Rheum Dis, 2009 Sep;12(3):211-5.
    PMID: 20374348 DOI: 10.1111/j.1756-185X.2009.01412.x
    AIM: The objectives of this study are to provide data regarding the prevalence of anti-cyclic citrullinated peptide (CCP) antibodies in Malaysian rheumatoid arthritis (RA) patients and to correlate the levels of anti-CCP antibody with the Disease Activity Score (DAS).
    METHOD: We studied the prevalence of anti-CCP antibodies in 51 RA patients attending our clinic and 29 controls. We also looked for correlation between anti-CCP antibody levels with the DAS and parameters such as duration of disease, rheumatoid factor (RF) and disease-modifying anti rheumatic drug (DMARD) usage.
    RESULTS: None of the controls demonstrated anti-CCP antibodies. Forty-one out of 51 patients (80.4%) were positive for anti-CCP antibodies. Sensitivity and specificity were 80.4% and 100% respectively in this study. Anti-CCP levels correlated significantly with rheumatoid factor, but no correlation was observed with the other parameters.
    CONCLUSIONS: Anti-CCP antibody is prevalent in Malaysian RA patients at 80.4% and more sensitive than RF in our cohort of established RA patients. Even though the anti-CCP levels correlated with RF, it did not show correlation with DAS.
  13. Sthaneshwar P, Prathibha R, Yap SF
    Malays J Pathol, 2005 Jun;27(1):29-32.
    PMID: 16676690
    Thyrotoxic periodic paralysis (TPP) is a medical emergency characterised by sudden onset of muscle weakness with hypokalemia that resolves with the treatment of hyperthyroidism. We report three cases of thyrotoxic periodic paralysis seen at the Accident and Emergency Care Department, University of Malaya Medical Centre in a period of four months. We also review the clinical presentation, pathophysiology, biochemical features and management of TPP. All three patients were young Asian males, presenting with muscle weakness of sudden onset. The first patient presented with lower limb weakness and had symptoms of thyrotoxicosis and goitre. He had a previous similar episode which resolved spontaneously. The second patient presented with quadriplegia, respiratory acidosis and had no signs and symptoms of thyrotoxicosis. The electrocardiogram of this patient showed normal sinus rhythm with U wave in V3 and a flat T wave, which are characteristic of hypokalaemia. The third patient, who was a known case of thyrotoxicosis, was admitted thrice for hypokalemic paralysis during the study period. All cases had low serum potassium, suppressed TSH and elevated T4 confirming thyrotoxic periodic paralysis. Potassium therapy was useful during the crisis; however prophylactic potassium has not been shown to prevent attacks as seen in one of our cases.
  14. Sthaneshwar P, Yap SF, Jayaram G
    Malays J Pathol, 2002 Jun;24(1):53-8.
    PMID: 16329556
    Pleural effusion is a common diagnostic problem. The analysis of serum and pleural fluid for tumour markers is widely used as a diagnostic aid in clinical practice. The aim of the present study was to determine the usefulness of simultaneous quantification of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA-125) in distinction of malignant from benign effusion. Data from a total of 78 patients including 53 patients with benign and 25 patients with malignant effusion was evaluated. The cut-off values for differentiating benign from malignant effusions were determined using results obtained from patients with known benign effusions (mean + 2 SD, 95% confidence interval). The cut-off for CEA and CA-125 were 5.1 ng/ml and 1707 IU/ml respectively. CEA assay in pleural fluid had an acceptable sensitivity and good specificity of 64% and 98% respectively. CA-125 had a sensitivity of 36% and specificity of 94%. The combination of the two tumour markers gave a sensitivity of 72% and specificity of 92.4%. We suggest a good clinical strategy may be to begin with CEA measurement (assay specificity 98%); if CEA is below the cut-off value (negative), CA-125 could then be measured to improve the sensitivity of detection of malignant effusions. However, measurement of these tumour markers is not cost effective from the point of view that it does not give information on the type of malignancy present. The latter has to be determined either by histological or cytological study.
  15. Azizi A, Sthaneshwar P, Shanmugam H, Arumugam S
    Pathology, 2015 Aug;47(5):495-7.
    PMID: 26126045 DOI: 10.1097/PAT.0000000000000286
  16. Sthaneshwar P, Jamaluddin FA, Fan YS
    Pathology, 2010;42(5):454-6.
    PMID: 20632822 DOI: 10.3109/00313025.2010.493861
    The aim of this study was to evaluate the distribution of cardiac troponin I (cTnI) values, measured by the ADVIA TnI-Ultra method in a multi-ethnic group and to determine the imprecision of the assay.
  17. Zainuddin NM, Sthaneshwar P, Vethakkan SRDB
    Malays J Pathol, 2019 Dec;41(3):369-372.
    PMID: 31901925
    INTRODUCTION: Hyponatraemia is one of the most frequent laboratory findings in hospitalised patients. We present an unusual case of hyponatraemia in a 23-year-old female secondary to acute intermittent porphyria (AIP), a rare inborn error of metabolism.

    CASE REPORT: The patient presented with upper respiratory tract infection, fever, seizures and abdominal pain. An initial diagnosis of encephalitis was made. In view of the unexplained abdominal pain with other clinical findings such as posterior reversible encephalopathy syndrome by CT brain, temporary blindness as well as hyponatraemia, acute intermittent porphyria was suspected. Urine delta aminolaevulinic acid (δ-ALA) and porphobilinogen were elevated confirming the diagnosis of AIP. Genetic studies were done for this patient. The patient had a complete resolution of her symptoms with carbohydrate loading and high caloric diet.

    CONCLUSION: Although rare, AIP should be considered as a cause of hyponatraemia in a patient who presents with signs and/or symptoms that are characteristic of this disease.

  18. Zulkufli NS, Sthaneshwar P, Chan WK
    Singapore Med J, 2023 Mar;64(3):188-195.
    PMID: 35139628 DOI: 10.11622/smedj.2022019
    INTRODUCTION: The diagnosis of Wilson disease (WD) is plagued by biochemical and clinical uncertainties. Thus, calculated parameters have been proposed. This study aimed to: (a) compare the diagnostic values of non-caeruloplasmin copper (NCC), NCC percentage (NCC%), copper-caeruloplasmin ratio (CCR) and adjusted copper in WD; and (b) derive and evaluate a discriminant function in diagnosing WD.

    METHODS: A total of 213 subjects across all ages who were investigated for WD were recruited. WD was confirmed in 55 patients, and the rest were WD free. Based on serum copper and caeruloplasmin values, NCC, NCC%, CCR and adjusted copper were calculated for each subject. A function was derived using discriminant analysis, and the cut-off value was determined through receiver operating characteristic analysis. Classification accuracy was found by cross-tabulation.

    RESULTS: Caeruloplasmin, total copper, NCC, NCC%, CCR, adjusted copper and discriminant function were significantly lower in WD compared to non-WD. Discriminant function showed the best diagnostic specificity (99.4%), sensitivity (98.2%) and classification accuracy (99.1%). Caeruloplasmin levels <0.14 g/L showed higher accuracy than the recommended 0.20 g/L cut-off value (97.7% vs. 87.8%). Similarly, molar NCC below the European cut-off of 1.6 umol/L showed higher accuracy than the American cut-off of 3.9 umol/L (80.3% vs. 59.6%) (P < 0.001). NCC%, mass NCC, CCR and adjusted copper showed poorer performances.

    CONCLUSION: Discriminant function differentiates WD from non-WD with excellent specificity, sensitivity and accuracy. Performance of serum caeruloplasmin <0.14 g/L was better than that of <0.20 g/L. NCC, NCC%, CCR and adjusted copper are not helpful in diagnosing WD.

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