1.Evaluation of different methods for the effective isolation of high-quality DNA from rodent faecal samples
Nik Amirah Auni Nik Mohd Asri ; Zarina Amin ; Yew Chee Wei
Malaysian Journal of Microbiology 2023;19(no.6):610-616
Aims:
The inefficient lysis of recalcitrant bacterial cell wall and subsequent isolation of DNA from environmental samples can lead to a bias in the qualitative and quantitative assessment of bacteria present in the sample. Thus, the selection of an optimum DNA isolation method is the important first step for biosurveillance and metagenomic analyses. This study aims to determine the optimal DNA isolation method out of four commercial DNA isolation kits (A, B, C and D) and two conventional methods (E and F), for rodent faecal droppings. The key selection criterion is the general bacterial diversity contained in the isolated DNA, as evaluated by the Shannon-Weaver index based on the maximal number of PCR-amplicons of partial 16S rRNA gene, derived from each method. The amplicons were separated in accordance with their difference in nucleotide sequences via DGGE.
Methodology and results:
Five faecal samples of wild rodents were collected from different sites and preserved in DNA/RNA shield reagent (Zymo Research). Each sample was extracted, and the DNA extracts were then subjected to amplification of the bacterial 16S rRNA and DGGE separation of the amplicons. Method E showed a higher yield of DNA (average 324.22 ng/µL) as compared to the other methods. However, the majority of the DNA extracts showed partial degradation. The DGGE profiles showed the highest number of amplicons were generated from DNA extracted from Method A and B with a total of 168 and 167 respectively. This is indicated by the Shannon-Weaver index which were 0.306 and 0.305, respectively.
Conclusion, significance and impact of study
Method A is the optimum DNA isolation method for rodent faecal samples as its isolated DNA contains the most diverse bacteria. The isolated DNA can then be used for PCR-biosurveillance or metagenomic sequencing and analyses.
2.Predictors and outcomes of high-flow nasal cannula failure following extubation: A multicentre observational study.
Amit KANSAL ; Shekhar DHANVIJAY ; Andrew LI ; Jason PHUA ; Matthew Edward COVE ; Wei Jun Dan ONG ; Ser Hon PUAH ; Vicky NG ; Qiao Li TAN ; Julipie Sumampong MANALANSAN ; Michael Sharey Nocon ZAMORA ; Michael Camba VIDANES ; Juliet Tolentino SAHAGUN ; Juvel TACULOD ; Addy Yong Hui TAN ; Chee Kiang TAY ; Yew Woon CHIA ; Duu Wen SEWA ; Meiying CHEW ; Sennen J W LEW ; Shirley GOH ; Jonathan Jit Ern TAN ; Kollengode RAMANATHAN ; Amartya MUKHOPADHYAY ; Kay Choong SEE
Annals of the Academy of Medicine, Singapore 2021;50(6):467-473
INTRODUCTION:
Despite adhering to criteria for extubation, up to 20% of intensive care patients require re-intubation, even with use of post-extubation high-flow nasal cannula (HFNC). This study aims to identify independent predictors and outcomes of extubation failure in patients who failed post-extubation HFNC.
METHODS:
We conducted a multicentre observational study involving 9 adult intensive care units (ICUs) across 5 public hospitals in Singapore. We included patients extubated to HFNC following spontaneous breathing trials. We compared patients who were successfully weaned off HFNC with those who failed HFNC (defined as re-intubation ≤7 days following extubation). Generalised additive logistic regression analysis was used to identify independent risk factors for failed HFNC.
RESULTS:
Among 244 patients (mean age: 63.92±15.51 years, 65.2% male, median APACHE II score 23.55±7.35), 41 (16.8%) failed HFNC; hypoxia, hypercapnia and excessive secretions were primary reasons. Stroke was an independent predictor of HFNC failure (odds ratio 2.48, 95% confidence interval 1.83-3.37). Failed HFNC, as compared to successful HFNC, was associated with increased median ICU length of stay (14 versus 7 days,
CONCLUSION
Post-extubation HFNC failure, especially in patients with stroke as a comorbidity, remains a clinical challenge and predicts poorer clinical outcomes. Our observational study highlights the need for future prospective trials to better identify patients at high risk of post-extubation HFNC failure.
Adult
;
Airway Extubation
;
Cannula
;
Critical Care
;
Female
;
Humans
;
Intensive Care Units
;
Male
;
Middle Aged
;
Respiratory Insufficiency/therapy*
;
Singapore/epidemiology*
3.A summary of the Malaysian Clinical Practice Guidelines on the management of postmenopausal osteoporosis, 2022
Terence Ing WEI ONG ; Lee Ling LIM ; Siew Pheng CHAN ; Winnie Siew SWEE CHEE ; Alan Swee HOCK CH’NG ; Elizabeth GAR MIT CHONG ; Premitha DAMODARAN ; Fen Lee HEW ; Luqman bin IBRAHIM ; Hui Min KHOR ; Pauline Siew MEI LAI ; Joon Kiong LEE ; Ai Lee LIM ; Boon Ping LIM ; Sharmila Sunita PARAMASIVAM ; Jeyakantha RATNASINGAM ; Yew Siong SIOW ; Alexander Tong BOON TAN ; Nagammai THIAGARAJAN ; Swan Sim YEAP
Osteoporosis and Sarcopenia 2023;9(2):60-69
Objectives:
The aim of these Clinical Practice Guidelines is to provide evidence-based recommendations to assist healthcare providers in the screening, diagnosis and management of patients with postmenopausal osteoporosis (OP).
Methods:
A list of key clinical questions on the assessment, diagnosis and treatment of OP was formulated. A literature search using the PubMed, Medline, Cochrane Databases of Systematic Reviews, and OVID electronic databases identified all relevant articles on OP based on the key clinical questions, from 2014 onwards, to update from the 2015 edition. The articles were graded using the SIGN50 format. For each statement, studies with the highest level of evidence were used to frame the recommendation.
Results:
This article summarizes the diagnostic and treatment pathways for postmenopausal OP. Risk stratification of patients with OP encompasses clinical risk factors, bone mineral density measurements and FRAX risk estimates. Non-pharmacological measures including adequate calcium and vitamin D, regular exercise and falls prevention are recommended. Pharmacological measures depend on patients’ fracture risk status. Very high-risk individuals are recommended for treatment with an anabolic agent, if available, followed by an anti-resorptive agent. Alternatively, parenteral anti-resorptive agents can be used. High-risk individuals should be treated with anti-resorptive agents. In low-risk individuals, menopausal hormone replacement or selective estrogen receptor modulators can be used, if indicated. Patients should be assessed regularly to monitor treatment response and treatment adjusted, as appropriate.
Conclusions
The pathways for the management of postmenopausal OP in Malaysia have been updated. Incorporation of fracture risk stratification can guide appropriate treatment.