Complete mitochondrial genome of Dacus conopsoides (Insecta: Tephritidae) with tRNA gene duplication and molecular phylogeny of Dacini tribe

Sze-Looi Song,Hoi-Sen Yong,I. Wayan Suana,Phaik-Eem Lim,Praphathip Eamsobhana 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.3

To date there is only a single report on the complete mitochondrial genome of the Dacus fruit flies. We report here the whole mitogenome of Dacus conopsoides with first report of tRNA gene duplication in tephritid fruit flies determined using next-generation sequencing and discuss the molecular phylogeny of Dacini tribe. It had a total length of 15,852 bp, comprising 13 protein coding genes, 2 rRNA genes, 23 tRNA genes, and a non-coding region (A + T-rich control region). The 65-bp trnF gene was duplicated, and the 68-bp trnE gene was partially duplicated resulting in a 31-bp pseudogene. The cloverleaf structure for trnN, trnH, and trnF lacked the TΨC-loop, while trnS lacked the D-stem. The start codons for the protein coding genes included 6 ATG, 3 ATC, 2 ATA, and 1 each of ATT and TCG. Seven PCGs had TAA stop codon, two had TAG and four had incomplete T stop codon. Molecular phylogeny based on 15 mt-genes (13 PCGs +2 rRNA genes) and 30 taxa of Tephritidae indicated D. conopsoides forming a monophyletic sister group with D. longicornis supported by high bootstrap value. The lineage containing also the monophyletic genus Zeugodacus. The Dacini and Ceratitidini tribes of the subfamily Dacinae were monophyletic but the subfamilies Dacinae and Trypetinae were paraphyletic. A broader taxa sampling of the Tephritidae is needed to better elucidate the phylogenetics and systematics of the tribes and subfamilies of tephritid fruit flies.

Isolation of a Quinone-rich Fraction from Ardisia crispa Roots and its Attenuating Effects on Murine Skin Tumorigenesis

Yeong, Looi Ting,Hamid, Roslida Abdul,Yazan, Latifah Saiful,Khaza'ai, Huzwah Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Ardisia crispa (Family: Myrsinaceae) is an evergreen, fruiting shrub that has been traditionally used as folklore medicine. Despite a scarcity of research publications, we have succeeded in showing suppressive effects on murine skin papillomagenesis. In extension, the present research was aimed at determining the effect of a quinone-rich fraction (QRF) isolated from the same root hexane extract on both initiation and promotion stages of carcinogenesis, at the selected dose of 30 mg/kg. Mice (groups I-IV) were initiated with a single dose of 7,12-dimethylbenz(${\alpha}$)anthracene (DMBA, $100{\mu}g/100{\mu}l$) followed by repeated promotion of croton oil (1%) twice weekly for 20 weeks. In addition, group I (anti-initiation) received QRF 7 days before and after DMBA; group II (anti-promotion) received QRF 30 minutes before each croton oil application; group III (anti-initiation/promotion) was treated with QRF as a combination of group I and II. A further two groups served as vehicle control (group V) and treated control (group VI). As carcinogen control, group IV showed the highest tumor volume ($8.79{\pm}5.44$) and tumor burden ($3.60{\pm}1.17$). Comparatively, group III revealed only 20% of tumor incidence, tumor burden ($3.00{\pm}1.00$) and tumor volume ($2.40{\pm}1.12$), which were significantly different from group IV. Group II also showed significant reduction of tumor volume (3.11), tumor burden (3.00) and tumor incidence (11.11%), along with prominent increase of latency period of tumor formation (week 12). Group I, nonetheless, demonstrated marked increment of tumor incidence by 40% with prompted latency period of tumor formation (week 7). No tumor formation was observed in groups V and VI. This study provided clear evidence of inhibitory effects of QRF during promotion period which was in agreement with our previous findings. The mechanism(s) underlying such effects have yet to be elucidated.

Complete mitochondrial genome of Bactrocera ritsemai (Insecta: Tephritidae) and phylogenetic relationship with its congeners and related tephritid taxa

Sze-Looi Song,Hoi-Sen Yong,I. Wayan Suana,Phaik-Eem Lim 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.1

Bactrocera ritsemai is a dacine fruit fly found in Indonesia. We report here the complete mitogenome of this fruitfly from Lombok, Indonesia determined by Illumina MiSeq sequencing and its phylogenetic relationship with itscongeners and related tephritid taxa. The whole mitogenome of B. ritsemai had a total length of 15,927 bp,comprising 37 genes – 13 protein-coding genes (PCGs), 2 ribosomal ribonucleic acid (rRNA) and 22 transferribonucleic acid (tRNA) genes – and a control region (D-loop). Of the PCGs, 6 (atp6, cob, cox2, cox3, nad4, nad4l)had ATG start codon, 4 (nad2, nad3, nad5, nad6) had ATT, and one each had ATA (nad1), GTG (atp8) and TCG(cox1). Seven PCGs (atp6, atp8, cox2, cox3, nad2, nad4l, nad6) had TAA stop codon, 3 (cob, nad3, nad4) had TAG,and 3 had incomplete stop codon (cox1 – TA; nad1, nad5 – T). The TΨC-loop of tRNA was absent in trnF whiletrnS1 lacked the DHU-loop. Phylogenetic analysis based on 15 mt-genes (13 PCGs+2 rRNA genes) indicated B. ritsemai forming a sister group with B. umbrosa and the subgenus Bactrocera was monophyletic. The generaBactrocera and Zeugodacus were monophyletic while the subfamilies Dacinae and Tephritinae were paraphyletic. A broader taxa sampling of the Tephritidae is needed to better elucidate the phylogenetics and systematics of thetribes and subfamilies of tephritid fruit flies.

Investigation of photovoltaic thermoelectric air-conditioning system for room application under tropical climate

Kar Kin Looi,Aklilu Tesfamichael Baheta,Khairul Habib 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.5

Photovoltaic thermoelectric air-conditioning system (PT A/C) system could be a greater option compared to conventional A/C system as it is Freon-free and absence of moving parts. This study investigated the cooling and dehumidification performance of a PT A/C that is solely powered by solar energy under tropical climate conditions. The system is built with 9 pieces of thermoelectric to provide cooling for a test chamber of 3.6 m 3 volume. The effect of input current on the system’s cooling and moisture removal rate were investigated and results showed that 5 A is the optimum current level, providing an average of 181 W cooling capacity and 0.14 ltr/hour of moisture removal rate at the given ambient conditions. During the operation, indoor temperature of the test chamber was 4 °C lower than the unconditioned chamber and 7.7 °C compared to the ambient temperature. Whereas the indoor relative humidity varies between 58~83 %. Furthermore, for a 12 hours operation, the system consumes 1.45 kWh of energy, and delivered temperature between 23.8 to 27.8 ºC at 5 A.

Pulsed low-dose rate radiotherapy for recurrent bone sarcomas: case reports and brief review

Ru Xin Wong(Ru Xin Wong ),Zubin Master(Zubin Master ),Eric Pang(Eric Pang ),Valerie Yang(Valerie Yang ),Wen Shen Looi(Wen Shen Looi ) 대한방사선종양학회 2024 Radiation Oncology Journal Vol.42 No.1

Purpose: Re-irradiation for bulky recurrent sarcoma carries significant risks. Pulsed low-dose rate radiotherapy (PLDR) is an attractive option for re-irradiation due to inherent radiobiological advantages. Materials and Methods: We present two patients who underwent re-irradiation using PLDR technique, followed by a literature review. Results: The first case is that of a 76-year-old male who developed an in-field recurrence of a bulky pelvic bone high-grade chondrosarcoma after he was treated with definitive radiotherapy using helical TomoTherapy with a total dose of 66 Gy. The patient was re-irradiated using PLDR with a shrinking field technique; 50 Gy in 2 Gy fractions followed by a boost of 20 Gy in 2 Gy fractions. The patient remains disease-free without significant toxicity 60 months post-irradiation. The second case is that of an 82-year-old female who was treated with a definitive irradiation of 66 Gy in 33 fractions for a right shoulder grade II chondrosarcoma. She developed an in-field recurrence 28 months later and presented with bulky disease causing brachial plexopathy and lymphedema. The patient was re-irradiated with a palliative intent to a total dose of 50 Gy in 2 Gy fractions over 5 weeks using PLDR. Brachial plexopathy resolved shortly after re-irradiation, but local progression near the surface was evident 8 months later. She passed away from unrelated causes 11 months later. Conclusion: We present two cases highlighting our early experience with PLDR, which was effective in the re-irradiation of recurrent bony sarcoma. Our study highlights PLDR as an option for re-irradiation in recurrent unresectable tumors.

Colorectal Carcinoma in Malaysians: DNA Mismatch Repair Pattern in a Multiethnic Population

Cheah, Phaik-Leng,Looi, Lai-Meng,Teoh, Kean-Hooi,Rahman, Nazarina Abdul,Wong, Li-Xuan,Tan, Soo-Yong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

Background: The interesting preponderance of Chinese with colorectal carcinoma (CRC) amongst the three major ethnic groups in Malaysia prompted a study to determine DNA mismatch repair (MMR) status in our CRC and attempt correlation with patient age, gender and ethnicity as well as location, grade, histological type and stage of tumour. Histologically re-confirmed CRC, diagnosed between $1^{st} $January 2005 and $31^{st}$ December 2007 at the Department of Pathology, University of Malaya Medical Centre, were immunohistochemically stained with monoclonal antibodies to MMR proteins, MLH1, MSH2, MSH6 and PMS2 on the Ventana Benchmark XT autostainer. Of the 142 CRC cases entered into the study, there were 82 males and 60 females (M:F=1.4:1). Ethnically, 81 (57.0%) were Chinese, 32 (22.5%) Malays and 29 (20.4%) Indians. The patient ages ranged between 15-87 years (mean=62.4 years) with 21 cases <50-years and 121 ${\geq}50$-years of age. 14 (9.9%) CRC showed deficient MMR (dMMR). Concurrent loss of MLH1 and PMS2 occurred in 10, MSH2 and MSH6 in 2 with isolated loss of MSH6 in 1 and PMS2 in 1. dMMR was noted less frequently amongst the Chinese (6.2%) in comparison with their combined Malay and Indian counterparts (14.8%), and was associated with right sided and poorly differentiated tumours (p<0.05). 3 of the 5 (60.0%) dMMR CRC cases amongst the Chinese and 1 of 9 cases (11.1%) amongst the combined Malay and Indian group were <50-years of age. No significant association of dMMR was noted with patient age and gender, tumour stage or mucinous type.

Assessing how an unofficial brand partnership affects a brand image: The case of the Satan Shoes

Song Y. Greg,Looi Jiemin,Kang Eun Yeon 한국마케팅과학회 2023 Journal of Global Fashion Marketing Vol.14 No.4

This study investigates how unofficial, third-party brand partner- ships detrimentally impact brand attitudes. It also addresses an underexplored research area by evaluating whether brands’ response strategies can effectively mitigate reputational damages incurred from paracrises – trivial yet publicly visible incidents alle- ging their involvement in socially irresponsible and unethical beha- viors. This study is premised upon the Satan Shoes scandal, in which musician Lil Nas X and the art collective MSCHF altered and sold Nike footwear without obtaining the company’s authorization, resulting in public backlash on social media and a lawsuit from Nike to recall the modified sneakers. Sentiment analysis indicated that consumers expressed negative brand attitudes toward Nike in response to the scandal. Topic modeling also revealed key themes regarding the product design, moral controversies surrounding the Satan Shoes, and Nike’s lawsuit against MSCHF. Time series analysis further demonstrated that the lawsuit effectively positioned Nike as a victim, thereby disassociating the brand from the paracrisis.

Cyclooxygenase-2 Expression in Invasive Breast Carcinomas of No Special Type and Correlation with Pathological Profiles Suggest a Role in Tumorigenesis Rather than Cancer Progression

Misron, Nurul Akmar,Looi, Lai-Meng,Mustapha, Nik Raihan Nik Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.4

Background: COX-2 has been shown to play an important role in the development of breast cancer and increased expression has been mooted as a poor prognostic factor. The purpose of this study was to investigate the relationship between COX-2 immunohistochemical expression and known predictive and prognostic factors in breast cancer in a routine diagnostic histopathology setting. Materials and Methods: Formalin-fixed paraffin-embedded tumour tissue of 144 no special type (NST) invasive breast carcinomas histologically diagnosed between January 2009 and December 2012 in Hospital Sultanah Bahiyah, Alor Setar, Kedah were immunostained with COX-2 antibody. COX-2 overexpression was analysed against demographic data, hormone receptor status, HER2-neu overexpression, histological grade, tumour size and lymph node status. Results: COX-2 was overexpressed in 108/144 (75%) tumours and was significantly more prevalent (87%) in hormone receptor-positive tumours. There was no correlation between COX-2 overexpression and HER2/neu status. Triple negative cancers had the lowest prevalence (46%) (p<0.05). A rising trend of COX-2 overexpression with increasing age was observed. There was a significant inverse relationship with tumour grade (p<0.05), prevalences being 94%, 83% and 66% in grades 1, 2 and 3 tumours, respectively. A higher prevalence of COX-2 overexpression in smaller size tumours was observed but this did not reach statistical significance. There was no relationship between COX-2 expression and lymph node status. Conclusions: This study did not support the generally held notion that COX-2 overexpression is linked to poor prognosis, rather supporting a role in tumorigenesis. Larger scale studies with outcome data and basic studies on cancer pathogenetic pathways will be required to cast further light on whether COX-2 inhibitors would have clinical utility in cancer prevention or blockage of cancer progression. In either setting, the pathological assessment for COX-2 overexpression in breast cancers would have an important role in the selection of cancer patients for personalized therapy with COX-2 inhibitors.

p16^INK4a is a Useful Marker of Human Papillomavirus Integration Allowing Risk Stratification for Cervical Malignancies

Cheah, Phaik-Leng,Looi, Lai-Meng,Teoh, Kean-Hooi,Mun, Kein-Seong,Nazarina, Abdul Rahman Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.2

The present study was conducted to assess utility of $p16^{INK4a}$ immunopositivity as a surrogate marker for genomic integration of high-risk human papillomavirus infection (hrHPV). A total of 29 formalin-fixed, paraffin-embedded cervical low-grade squamous intraepithelial lesions (LSILs), 27 high-grade squamous intraepithelial lesions (HSILs) and 53 invasive squamous cell carcinomas (SCCs), histologically-diagnosed between 1st January 2006 to 31st December 2008 at the University of Malaya Medical Centre were stained for $p^{16INK4a}$ (CINtec Histology Kit (REF 9511, mtm laboratories AG, Heidelberg, Germany). Immunopositvity was defined as diffuse staining of the squamous cell cytoplasm and or nucleus (involving > 75% of the intraepithelial lesions or SCCs). Staining of basal and parabasal layers of intraepithelial lesions was pre-requisite. One (3.4%) LSIL, 24 (88.9%) HSIL and 46 (86.8%) SCC were $p^{16INK4a}$ immunopositive. All normal squamous epithelium did not express $p16^{INK4a}$. $p16^{INK4a}$ expression was significantly lower (p<0.05) in LSIL compared with HSIL and SCC with no difference in expression between HSIL and SCC. The increased $p16^{INK4a}$ immunopositivity in HSIL and SCC appears in line with the integrated existence of the hrHPV and may provide more insightful information on risk of malignant transformation of cervical squamous intraepithelial lesions than mere hrHPV detection.

Tissue Microarray Immunohistochemical Profiles of p53 and pRB in Hepatocellular Carcinoma and Hepatoblastoma

Azlin, Abdul Hadi,Looi, Lai Meng,Cheah, Phaik Leng Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.9

The tumour suppressor genes, p53 and pRb, are known to play important roles in neoplastic transformation. While molecular routes to the uncontrolled growth of hepatocytes, leading to primary liver cancer have generated considerable interest, the roles of p53 and pRb mutations in hepatocellular carcinoma (HCC) and hepatoblastoma (HB) remain to be clarified. We examined the immunohistochemical expression of p53 and pRb gene products in 26 HCC and 9 HB, sampled into tissue microarray blocks. 10 (38%) of 26 HCC showed > 10% tumour nuclear staining for p53 protein, 3 of these also being HbsAg positive. Conversely, none of 9 HB expressed nuclear p53 immunopositivity. Some 24 (92%) HCC and 8 (89%) HB showed loss of pRb nuclear expression. Two of the 26 HCC and one of the 9 HB showed >10% tumour nuclear staining for pRb protein. Our results suggest that p53 does not have an important role in the development of HB but may contribute in HCC. There is also loss of pRb expression in the majority of HCC and HB, supporting loss of pRb gene function in the hepatocarcinogenesis pathway. However, a comparison of the staining profiles of p53 and pRb proteins in HCC and HB did not reveal a consistent pattern to differentiate between the two types of tumours immunohistochemically. Hence the use of p53 and pRB protein expression has no contribution in the situation where there is a diagnostic difficulty in deciding between HCC and HB.