Machine learning-based clinical decision support using laboratory data

Artificial intelligence (AI) and machine learning (ML) are becoming vital in laboratory medicine and the broader context of healthcare. In this review article, we summarized the development of ML models and how they contribute to clinical laboratory workflow and improve patient outcomes. The process of ML model development involves data collection, data cleansing, feature engineering, model development, and optimization. These models, once finalized, are subjected to thorough performance assessments and validations. Recently, due to the complexity inherent in model development, automated ML tools were also introduced to streamline the process, enabling non-experts to create models. Clinical Decision Support Systems (CDSS) use ML techniques on large datasets to aid healthcare professionals in test result interpretation. They are revolutionizing laboratory medicine, enabling labs to work more efficiently with less human supervision across pre-analytical, analytical, and post-analytical phases. Despite contributions of the ML tools at all analytical phases, their integration presents challenges like potential model uncertainties, black-box algorithms, and deskilling of professionals. Additionally, acquiring diverse datasets is hard, and models' complexity can limit clinical use. In conclusion, ML-based CDSS in healthcare can greatly enhance clinical decision-making. However, successful adoption demands collaboration among professionals and stakeholders, utilizing hybrid intelligence, external validation, and performance assessments.

Training and Competency Strategies for Point-of-Care Testing

The increased availability and use of POCT are being influenced by many factors, such as; industry trends to move towards patient-centered care and healthcare decentralization, the increasing prevalence of infectious diseases also including the current use of Rapid SARS-CoV-2 Testing, a growing incidence of lifestyle diseases such as diabetes, heart disease, and hypertension, as well as advances in in-vitro diagnostic medical technologies. The use of POCT can increase the efficiency of services and improve outcomes for patients. However, the variability of the testing environment and conditions as well as the competency of staff performing the tests may have a significant impact on the quality and accuracy of POCT results. A majority of the staff who perform POCT are not trained laboratory staff and may not be as knowledgeable about the processes involved in testing, such as patient preparation, sample collection, management of equipment and supplies, instrument calibration and maintenance, the performance of the test, quality control, interpretation of the results, and reporting/documentation of results in each patient's context. Therefore, staff performing POCT must have the proper training and experience to ensure test results are accurate and reliable. This short communication outlines the specific requirements for staff training based on international standards which need to be considered to ensure the quality of test results and describes competency criteria required for compliance with POCT.

Vitamin D levels in patients with breast cancer: importance of dressing style

BACKGROUND

Vitamin D deficiency is a potentially modifiable risk factor that may be targeted for breast cancer (BC) prevention. It may also be related to prognosis after diagnosis and treatment. The aim of our study was to determine the prevalence of vitamin D deficiency as measured by serum 25-hydroxy vitamin D (25-OHD) levels in patients with BC and to evaluate its correlations with life-style and treatments.

MATERIALS AND METHODS

This study included 186 patients with stage 0-III BC treated in our breast center between 2010-2013. The correlation between serum baseline 25-OHD levels and supplement usage, age, menopausal status, diabetes mellitus, usage of bisphosphonates, body-mass index (BMI), season, dressing style, administration of systemic treatments and radiotherapy were investigated. The distribution of serum 25-OHD levels was categorized as deficient (<10ng/ ml), insufficient (10-24 ng/ml), and sufficient (25-80 ng/ml).

RESULTS

The median age of the patients was 51 years (range: 27-79 years) and 70% of them had deficient/insufficient 25-OHD levels. On univariate analysis, vitamin D deficiency/insufficiency was more common in patients with none or low dose vitamin D supplementation at the baseline, high BMI (≥25), no bisphosphonate usage, and a conservative dressing style. On multivariate analysis, none or low dose vitamin D supplementation, and decreased sun-exposure due to a conservative dressing style were found as independent factors increasing risk of vitamin D deficiency/insufficiency 28.7 (p=0.002) and 13.4 (p=0.003) fold, respectively.

CONCLUSIONS

The prevalence of serum 25-OHD deficiency/insufficiency is high in our BC survivors. Vitamin D status should be routinely evaluated for all women, especially those with a conservative dressing style, as part of regular preventive care, and they should take supplemental vitamin D.

Detection of Epithelial Cell Transfer in Spinal Areas by Light Microscopy and Determining Any Tissue Coring via Cell Culture During Combined Spinal-Epidural Interventions

BACKGROUND AND OBJECTIVES

Epithelial tissue coring by spinal needles during subarachnoid injections may cause intraspinal epidermal tumors. Previous studies have investigated tissue transfer with different needle types during subarachnoid or epidural injection. This study deals with the transfer of epithelial tissue during combined spinal-epidural (CSE) anesthesia.

METHODS

We studied 68 American Society of Anesthesiologists I to III adult patients. CSE anesthesia was induced under aseptic conditions at the L2-3 or L3-4 interspace with patients in the lateral decubitus position. Cerebral spinal fluid, spinal needle stylet, fluid used to flush the interior of the spinal needle, fluid used to wash the exterior of the spinal needle, fluid used to flush the interior of the epidural needle, and fluid used to wash the exterior tip of the epidural needle were examined under light microscopy (n = 30 patients) or incubated in a cell-culture medium (n = 38 patients). Samples were incubated in cell-culture medium alone (n = 13) or in a cell-culture medium for 3 weeks and then in a medium with epidermal growth factor (n = 25). As a positive control, skin tissue samples were taken by punch biopsy from 10 randomly chosen patients who underwent CSE interventions. These samples were incubated in an enriched medium serum.

RESULTS

Light microscopy revealed that there was cell transfer in all phases in various rates: samples 1, 2, 3, 4, 5, and 6 contained epithelial cells and debris in ratios of 6.9%, 20.7%, 6.9%, 20.7%, 26.7%, and 33.3%, respectively. Epithelial cell colonization was detected in the cell-culture samples taken from the control group but not in the samples taken from the CSE group.

CONCLUSIONS

We could not reproduce the cells or cell debris obtained during the CSE interventions in vivo, which can be explained by a possible structural deformation of cells or the inadequacy of the amount of cells that were transferred.

Urinary nitrite excretion in low birth weight neonates with systemic inflammatory response syndrome

Increased nitric oxide (NO) levels are thought to play an important role in the pathophysiology of the systemic inflammatory response syndrome (SIRS) which is caused by disseminated vascular endothelial damage. Clinical studies have shown that urinary nitrite (NO2-) and nitrate (NO3-) excretions can be utilized as indexes of NO formation. The SIRS and NO relationship was investigated in 15 neonates with SIRS, gestational age 32.5 +/- 4.4 weeks and weight 1,737 +/- 753 g. The control group comprised 18 neonates with a gestational age of 32.8 +/- 3.5 weeks and a weight of 1,778 +/- 538 g. There was no significant difference in birth weights and gestational ages between the two groups (p > 0.05 and p > 0.05). The urinary nitrite levels obtained in the subjects were normalized for urinary creatinine concentrations. The mean urinary nitrite levels in the control group neonates were found to be 4.22 +/- 1.8 micromol/mmol creatinine on the 1st day, 4.09 +/- 2.28 on the 2nd, 3.62 +/- 1.6 on the 3rd, and 4.01 +/- 1.12 micromol/mmol creatinine on the 7th day. There were no statistically significant differences between these levels (p > 0.05). We determined urinary levels of nitrite in neonates in the study group within the first 24 h of SIRS symptoms and found these levels (18.35 +/- 11.16 micromol nitrite/mmol creatinine) to be elevated as compared with those of the control subjects on the 7th day of life (p < 0.0005). In conclusion, urinary nitrite excretion is significantly elevated in neonates with SIRS due to septic events, and these results suggest that NO might play a part in SIRS.

Influence of exercise training and age on uncoupling protein mRNA expression in brown adipose tissue

The ability to regulate body temperature diminishes with age. Exercise training is known to increase cardiovascular performance, and there is some evidence of a cross-adaptation between exercise and cold tolerance in young rats. The present study was designed to examine the effects of physical training by treadmill running on the capacity for brown adipose tissue (BAT) thermogenesis in young and old rats. To this end, we assessed BAT uncoupling protein (UCP) mRNA expression in sedentary and exercise-trained 5- and 25-mo-old F-344 rats. The amount of UCP mRNA, whether expressed as per unit RNA or per BAT, did not change with either age or training. These data indicate that there is no cross-adaptation by exercise on adaptive thermogenesis in BAT in either young or old rats.

Nuclear casein kinase 2 (CK-2) activity in human normal, benign hyperplastic, and cancerous prostate

In previous work, we had observed that chromatin-associated nonhistone protein phosphorylation, catalyzed by intrinsic protein kinase reaction in chromatin preparations from human benign prostatic hyperplasia (BPH) prostate samples was markedly elevated, compared with the normal prostate chromatin samples [Rayan et al: Cancer Res 45:2277-2282, 1985]. The properties of this protein kinase reaction were suggestive of the involvement of casein kinase(s). By employing the specific synthetic substrate for casein kinase 2 (CK-2) for assays in cellular fractions, we have shown that this protein kinase is present in human prostate chromatin. Its activity is increased in BPH chromatin by about 25-fold, as compared with its activity in the normal prostate chromatin. This suggests that CK-2 is a possible mediator of the enhanced phosphorylation of chromosomal proteins in BPH chromatin. By comparison, CK-2 activity in chromatin preparations from prostatic carcinoma samples was markedly less elevated than that of the BPH chromatin. Immunohistochemical analysis of the enzyme in human frozen sections of prostate tissue samples showed that the enzyme immunostaining was diffuse in the cytoplasm, but more intense in the nucleus, especially in the nucleoli. In general, the staining corresponded with the enzymic data. However, sections from prostatic carcinoma samples appeared to show differential staining, depending on the Gleason's grade of the sample. The samples with higher Gleason's grade showed less intense immunostain in the nucleus, compared with samples of lower Gleason's grade. Further, regions of sections in samples with higher Gleason's grade did not show any immunostaining. These differences in the characteristics of CK-2 expression in prostatic carcinoma samples may be potentially significant, but need to be evaluated further for their significance to the pathobiology of prostatic neoplasia.

Association of casein kinase 2 with nuclear chromatin in relation to androgenic regulation of rat prostate

Casein kinase 2 (CK-2) is a ubiquitous messenger-independent protein serine/threonine kinase that has been implicated in growth control. We have studied the activity and subcellular location of CK-2 in adult rat ventral prostate in relation to androgen withdrawal and administration. Androgen deprivation by castration results in a faster decline in CK-2 activity associated with prostatic nuclei than that in the cytosol. Nuclear CK-2 associated with chromatin is reduced at an even greater rate than that in the total nucleus. Reversal of these events by administration of a single dose of 5 alpha-dihydrotestosterone to adult rats castrated 144 hr previously was accompanied by a differential early enhancement of chromatin-associated CK-2 activity, with a concomitant decrease in the CK-2 activity present in the cytosol. Changes in the nuclear CK-2 activity correlated with the immunostainable enzyme protein in the nucleus. We propose that androgens evoke translocation of CK-2 from the cytoplasm to the nucleus (nucleoplasm) where its enhanced association with the chromatin constituents takes place. Conversely, withdrawal of circulating androgens due to castration evokes a dissociation of CK-2 from chromatin and eventual translocation of nucleoplasmic CK-2 to the cytoplasm. Modulations in the association of CK-2 with nuclear chromatin may represent an important mechanism of post-transcriptional regulation of nuclear CK-2 in relation to androgen action in the prostate.