A retrospective review of all bronchoscopy cases for investigation of lung cancer between January 1997 and December 1999 was done. The cases were included if endobronchial mass was visible (Group A) or when there was an abnormal mucosa and/or bronchial narrowing in the absence of a mass (Group B). All patients in Group A (n = 177) underwent endobronchial biopsy (EB) bronchial brushings (BB) and bronchial washings (BW). All cases in Group B underwent transbronchial biopsy (TBB), BB and BW. Only a small increase in the positive results for cancer was seen when cytology specimens (BB and BW) were added to EB (85.3% vs 88.1%, McNemar's P = 0.06) in Group A but there was a significant increase in Group B (37.3% vs 54.2%. McNemar's, P = 0.001). Therefore although cytology specimens did not significantly add to overall yield of positive results when endobronchial lesions were visible, when mass lesions were not visible, cytology specimens increased the yield by 16.9%.
Study site: Chest clinic, Hospital Sultanah Aminah (HSA), Johor Bahru, Johor, Malaysia
In this paper, single cells adhesion force was measured using a nanofork. The nanofork was used to pick up a single cell on a line array substrate inside an environmental scanning electron microscope (ESEM). The line array substrate was used to provide small gaps between the single cells and the substrate. Therefore, the nanofork could be inserted through these gaps in order to successfully pick up a single cell. Adhesion force was measured during the cell pick-up process from the deflection of the cantilever beam. The nanofork was fabricated using focused ion beam (FIB) etching process while the line array substrate was fabricated using nanoimprinting technology. As to investigate the effect of contact area on the strength of the adhesion force, two sizes of gap distance of line array substrate were used, i.e., 1 μm and 2 μm. Results showed that cells attached on the 1 μm gap line array substrate required more force to be released as compared to the cells attached on the 1 μm gap line array substrate.
Induced pluripotent stem cells (iPSC) are somatic cells reprogrammed to pluripotency by forced expression of pluripotency factors. These cells are shown to have the same pluripotent potential as embryonic stem cells (ESC) and considered as an alternative to the much controversial usage of ESC which involved human embryos. However, the traditional method in reprogramming cells into iPSC using genome-integrating retro- or lenti- viruses remains an obstacle for its application in clinical setting. Although numerous studies have been conducted for a safer DNA-based reprogramming, reprogramming of iPSC by genetic modifications may raise the possibility of malignant transformation and has been a major limitation for its usage in clinical applications. Therefore, there is a need for an alternative method to reprogram the cells without the use of gene editing and a much safer way to deliver transcription factors to induce pluripotency on target cells. Using protein transduction approach, a number of studies have demonstrated the generation of human iPSCs from human fibroblasts and mouse embryonic fibroblasts by direct delivery of reprogramming proteins. In this review, the definition and mechanism of HIV-TAT protein (a type of protein transduction domain) in delivering recombinant proteins, including the potential of protein-based delivery to induce iPSC were further discussed.
Drug-induced transformations in disease characteristics at the cellular and molecular level offers the opportunity to predict and evaluate the efficacy of pharmaceutical ingredients whilst enabling the optimal design of new and improved drugs with enhanced pharmacokinetics and pharmacodynamics. Machine learning is a promising in-silico tool used to simulate cells with specific disease properties and to determine their response toward drug uptake. Differences in the properties of normal and infected cells, including biophysical, biochemical and physiological characteristics, plays a key role in developing fundamental cellular probing platforms for machine learning applications. Cellular features can be extracted periodically from both the drug treated, infected, and normal cells via image segmentations in order to probe dynamic differences in cell behavior. Cellular segmentation can be evaluated to reflect the levels of drug effect on a distinct cell or group of cells via probability scoring. This article provides an account for the use of machine learning methods to probe differences in the biophysical, biochemical and physiological characteristics of infected cells in response to pharmacokinetics uptake of drug ingredients for application in cancer, diabetes and neurodegenerative disease therapies.
Cell contact formation, which is the process by which cells are brought into close proximity is an important biotechnological process in cell and molecular biology. Such manipulation is achieved by various means, among which dielectrophoresis (DEP) is widely used due to its simplicity. Here, we show the advantages in the judicious choice of the DEP microelectrode configuration in terms of limiting undesirable effects of dielectric heating on the cells, which could lead to their inactivation or death, as well as the possibility for cell clustering, which is particularly advantageous over the linear cell chain arrangement typically achieved to date with DEP. This study comprises of experimental work as well as mathematical modeling using COMSOL. In particular, we establish the parameters in a capillary-based microfluidic system giving rise to these optimum cell-cell contact configurations, together with the possibility for facilitating other cell manipulations such as spinning and rotation, thus providing useful protocols for application into microfluidic bioparticle manipulation systems for diagnostics, therapeutics or for furthering research in cellular bioelectricity and intercellular interactions.
Purpose: Guidelines advocate cystoscopy surveillance (CS) for non-muscle invasive bladder cancer (NMIBC) post-resection. However, cystoscopy is operator dependent and may miss upper tract lesions or carcinoma in-situ (CIS). Urine cytology is a common adjunct but lacks sensitivity and specificity in detecting recurrence. A new mRNA biomarker (CxBladder) was compared with urine cytology as an adjunct to cystoscopy in detecting a positive cystoscopy findings during surveillance cystoscopy in our center. Materials and Methods: Consented patients older than 18, undergoing CS for NMIBC, provide paired urine samples for cytology and CxBladder test. Patients with positive cystoscopy findings would undergo re-Trans Urethral Resection of Bladder Tumor (TURBT). Results: Thirty-five patients were enrolled from April to June 2019. Seven contaminated urine samples were excluded. The remaining cohort of 23 (82%) and 5 (18%) females had a mean age of 66.69 (36-89). Eight (29%) patients with positive cystoscopy finding underwent TURBT. All 8 patients also had positive CxBladder result. This shows that CxBladder has a sensitivity and negative predictive value (NPV) of 100%, specificity of 75% and positive predictive value (PPV) of 62% in predicting a positive cystoscopy finding. TURBT Histo-pathological findings showed Low-grade Ta NMIBC in one patient (4%), and 7 (25%) patients had inflammatory changes. Urine cytology was only positive in one patient with a positive cystoscopy finding. This led to a sensitivity of merely 13% and NPV of 74%, while specificity and PPV was 100% in predicting a positive cystoscopy finding. Conclusion: CxBladder had high NPV and sensitivity which accurately predicted suspicious cystoscopy findings leading to further investigation. It has great potential for use as adjunct to cystoscopy for surveillance of NMIBC.
To study the nature of endotoxin or lipopolysaccharide (LPS) induced inflammation, we developed a method of quantifying intracellular human neutrophil elastase (HNE) in lysed sputum polymorphs as a means to study the degranulation status of LPS-recruited neutrophils. Induced sputum, blood and exhaled nitric oxide (NO) were collected from 10 healthy non-atopic human subjects after inhaling a single 15 microg dose of Escherichia coil LPS in an open study. At 6 hours, LPS inhalation caused significant increase of sputum and blood neutrophils but without parallel increase in myeloperoxidase, HNE or interleukin-8 (IL-8) in sputum sol and blood, or exhaled NO. Intracellular HNE in lysed sputum polymorphs or purified blood neutrophils did not show any significant changes between inhaled LPS and saline, nor was there any appreciable change in percentage HNE release induced by N-Formyl-Met-Leu-Phe (fMLP) in vitro. We concluded that in healthy humans, the transient neutrophilic inflammation induced by a single dose of inhaled 15 microg LPS is mainly characterized by cell recruitment, not enhanced secretion of granular mediators or increased exhaled NO based on our experimental conditions.
The quantitative buffy coat (QBC) technique and conventional Giemsa thin blood smear was compared to determine the sensitivity and specificity of the technique in detecting blood parasitic infection of the rodent populations from four urban cities in Peninsular Malaysia. A total of 432 blood samples from four rat species (Rattus norvegicus, Rattus rattus diardii, Rattus exulans and Rattus argentiventer) were screened using both techniques and successfully detected two blood protozoan species (Trypanosoma lewisi and Plasmodium sp.) with Trypanosoma lewisi predominantly infecting the population. Results showed that Giemsa-stained thin film (GTF) was the better detection method on blood parasitemia (46.7%) compared to Quantitative Buffy Coat method (38.9%) with overall detection technique sensitivity and specificity at 83.2% and 74.8% respectively. The sensitivity in detection of Trypanosoma lewisi was 84.4% with value slightly lower for Plasmodium sp. infections at 76.6%. Statistical analysis proved that GTF technique was significantly more sensitive in the detection of blood protozoan infections in the rodent population compared to QBC (p<0.05).
Amyloid β (Aβ) deposition is a hallmark of Alzheimer's disease (AD). Vascular modifications, including altered brain endothelial cell function and structural viability of the blood-brain barrier due to vascular pulsatility, are implicated in AD pathology. Pulsatility of phenomena in the cerebral vasculature are often not considered in in vitro models of the blood-brain barrier. We demonstrate, for the first time, that pulsatile stretch of brain vascular endothelial cells modulates amyloid precursor protein (APP) expression and the APP processing enzyme, β-secretase 1, eventuating increased-Aβ generation and secretion. Concurrent modulation of intercellular adhesion molecule 1 and endothelial nitric oxide synthase (eNOS) signaling (expression and phosphorylation of eNOS) in response to pulsatile stretch indicates parallel activation of endothelial inflammatory pathways. These findings mechanistically support vascular pulsatility contributing towards cerebral Aβ levels.