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Fulltext Insights into potential causes of vascular hyperpermeability in dengue

Teo A, Chua CLL, Chia PY, Yeo TW

PLoS Pathog, 2021 Dec;17(12):e1010065.
PMID: 34882753 DOI: 10.1371/journal.ppat.1010065
Fulltext Reactions in Electrodeposited Cu/Sn and Cu/Ni/Sn Nanoscale Multilayers for Interconnects

Chia PY, Haseeb ASMA, Mannan SH

Materials (Basel), 2016 May 31;9(6).
PMID: 28773552 DOI: 10.3390/ma9060430

Miniaturization of electronic devices has led to the development of 3D IC packages which require ultra-small-scale interconnections. Such small interconnects can be completely converted into Cu-Sn based intermetallic compounds (IMCs) after reflow. In an effort to improve IMC based interconnects, an attempt is made to add Ni to Cu-Sn-based IMCs. Multilayer interconnects consisting of stacks of Cu/Sn/Cu/Sn/Cu or Cu/Ni/Sn/Ni/Sn/Cu/Ni/Sn/Ni/Cu with Ni = 35 nm, 70 nm, and 150 nm were electrodeposited sequentially using copper pyrophosphate, tin methanesulfonic, and nickel Watts baths, respectively. These multilayer interconnects were investigated under room temperature aging conditions and for solid-liquid reactions, where the samples were subjected to 250 °C reflow for 60 s and also 300 °C for 3600 s. The progress of the reaction in the multilayers was monitored by using X-ray Diffraction, Scanning Electron Microscope, and Energy dispersive X-ray Spectroscopy. FIB-milled samples were also prepared for investigation under room temperature aging conditions. Results show that by inserting a 70 nanometres thick Ni layer between copper and tin, premature reaction between Cu and Sn at room temperature can be avoided. During short reflow, the addition of Ni suppresses formation of Cu₃Sn IMC. With increasing Ni thickness, Cu consumption is decreased and Ni starts acting as a barrier layer. On the other hand, during long reflow, two types of IMC were found in the Cu/Ni/Sn samples which are the (Cu,Ni)₆Sn₅ and (Cu,Ni)₃Sn, respectively. Details of the reaction sequence and mechanisms are discussed.
Primary extragonadal vaginal yolk sac tumour: A case report

Wong YP, Yahaya A, Che Abdul Aziz R, Chia PY, Loh CK, Tan GC

Malays J Pathol, 2020 Aug;42(2):301-305.
PMID: 32860387

INTRODUCTION: Yolk sac tumour (YST) or endodermal sinus tumour is rare and typically seen in gonads.
CASE REPORT: We described a case of extragonadal vaginal YST in a one year and seven months old girl who presented with vaginal discharge and bleeding, and discuss its differential diagnosis and potential pitfalls in immunohistochemistry. She was found to have a suprapubic mass on examination. The serum alpha fetoprotein was 11919.4 ng/mL. Computed tomography of the pelvis revealed a large 6.4 cm heterogenous pelvic mass. Colposcopic examination of the pelvis showed a fungating vaginal mass that was subsequently confirmed as a yolk sac tumour. Immunohistochemically, the malignant cells were positive toward CKAE1/AE3, AFP and glypican-3, as well as CD117.
DISCUSSION: Solid pattern extragonadal vaginal YST may morphologically resemble dysgerminoma that is also CD117 positive, while the glandular pattern YST may have clear cytoplasm and is positive for cytokeratin; hence, may resemble clear cell carcinoma. Being mindful of these potential diagnostic caveats is necessary to prevent misdiagnosis.
Fulltext The role of hospital environment in transmissions of multidrug-resistant gram-negative organisms

Chia PY, Sengupta S, Kukreja A, S L Ponnampalavanar S, Ng OT, Marimuthu K

Antimicrob Resist Infect Control, 2020 02 11;9(1):29.
PMID: 32046775 DOI: 10.1186/s13756-020-0685-1

Infections by multidrug-resistant (MDR) Gram-negative organisms (GN) are associated with a high mortality rate and present an increasing challenge to the healthcare system worldwide. In recent years, increasing evidence supports the association between the healthcare environment and transmission of MDRGN to patients and healthcare workers. To better understand the role of the environment in transmission and acquisition of MDRGN, we conducted a utilitarian review based on literature published from 2014 until 2019.
Diagnostic utility of p57 immunohistochemistry and DNA ploidy analysis by fluorescence in situ hybridisation in hydatidiform moles

Wong YP, Chia WK, Selimin A, Chia PY, Mustangin M, Shuib S, et al.

Malays J Pathol, 2021 Dec;43(3):341-351.
PMID: 34958055

INTRODUCTION: Hydatidiform moles (HMs) include complete and partial moles, are the result of abnormal fertilisation. The accurate classification of HMs and its distinction from non-molar specimens is utmost important for clinical management and risk assessment. It is diagnostically challenging if the distinction is based solely on histomorphology with poor interobserver reproducibility, especially in early gestations. This study aimed to investigate the diagnostic ability of combined p57 immunohistochemistry and DNA ploidy analysis to distinguish between complete moles, partial moles and non-molar abortus.
MATERIALS AND METHODS: We included all HMs cases diagnosed in our centre over a six-year period. p57 immunohistochemistry stain was performed. Only nuclear immunoreactivity in >50% of cytotrophoblasts and villous stromal cells was regarded as positive for p57. DNA ploidy status was determined by fluorescence in situ hybridisation. A total of 250 cells from five chorionic villi were counted and were scored as diploid or triploid if more than 10% of nuclei demonstrated two or three signals, respectively.
RESULTS: A total of 51 cases originally diagnosed by histomorphology as complete mole (n = 18), partial mole (n = 24) and non-molar abortus (n = 9) were recruited. The cases were reclassified based on the p57 immunostaining pattern and DNA ploidy status, into 27 complete moles (p57-/diploid), 9 partial moles (p57+/triploid) and 15 non-molar abortus (p57+/diploid). The diagnostic accuracy by histomorphological features alone in each category: complete moles, partial moles and non-molar abortus was 78.4%, 70.6% and 88.2% respectively.
CONCLUSION: This study highlighted the importance of the utility of combined p57 immunostain and DNA ploidy analysis in arriving at an accurate diagnosis in HMs. An algorithmic approach utilising these ancillary techniques is advocated in routine diagnostic workup for a more refined diagnostic approach to HMs.
Fulltext Understanding antibody-dependent enhancement in dengue: Are afucosylated IgG1s a concern?

Teo A, Tan HD, Loy T, Chia PY, Chua CLL

PLoS Pathog, 2023 Mar;19(3):e1011223.
PMID: 36996026 DOI: 10.1371/journal.ppat.1011223
Predictors and Clinical Outcomes of Poor Platelet Recovery in Adult Dengue With Thrombocytopenia: A Multicenter, Prospective Study

Archuleta S, Chia PY, Wei Y, Syed-Omar SF, Low JG, Oh HM, et al.

Clin Infect Dis, 2020 07 11;71(2):383-389.
PMID: 31626692 DOI: 10.1093/cid/ciz850

BACKGROUND: Platelet transfusion is common in dengue patients with thrombocytopenia. We previously showed in a randomized clinical trial that prophylactic platelet transfusion did not reduce clinical bleeding. In this study, we aimed to characterize the predictors and clinical outcomes of poor platelet recovery in transfused and nontransfused participants.
METHODS: We analyzed patients from the Adult Dengue Platelet Study with laboratory-confirmed dengue with ≤20 000 platelets/μL and without persistent mild bleeding or any severe bleeding in a post hoc analysis. Poor platelet recovery was defined as a platelet count of ≤20 000/μL on Day 2. We recruited 372 participants from 5 acute care hospitals located in Singapore and Malaysia between 29 April 2010 and 9 December 2014. Of these, 188 were randomly assigned to the transfusion group and 184 to the control group.
RESULTS: Of 360 patients, 158 had poor platelet recovery. Age, white cell count, and day of illness at study enrollment were significant predictors of poor platelet recovery after adjustment for baseline characteristics and platelet transfusion. Patients with poor platelet recovery had longer hospitalizations but no significant difference in other clinical outcomes, regardless of transfusion. We found a significant interaction between platelet recovery and transfusion; patients with poor platelet recovery were more likely to bleed if given a prophylactic platelet transfusion (odds ratio 2.34, 95% confidence interval 1.18-4.63).
CONCLUSIONS: Dengue patients with thrombocytopenia who were older or presented earlier and with lower white cell counts were more likely to have poor platelet recovery. In patients with poor platelet recovery, platelet transfusion does not improve outcomes and may actually increase the risk of bleeding. The mechanisms of poor platelet recovery need to be determined.
CLINICAL TRIALS REGISTRATION: NCT01030211.