No abstract available.

Background: Calibration is a critical component for the reliability, accuracy, and precision of mass spectrometry measurements. Optimal practice in the construction, evaluation, and implementation of a new calibration curve is often underappreciated. This systematic review examined how calibration practices are applied to liquid chromatography-tandem mass spectrometry measurement procedures. Methods: The electronic database PubMed was searched from the date of database inception to April 1, 2022. The search terms used were “calibration,” “mass spectrometry,” and “regression.” Twenty-one articles were identified and included in this review, following evaluation of the titles, abstracts, full text, and reference lists of the search results. Results: The use of matrix-matched calibrators and stable isotope-labeled internal standards helps to mitigate the impact of matrix effects. A higher number of calibration standards or replicate measurements improves the mapping of the detector response and hence the accuracy and precision of the regression model. Constructing a calibration curve with each analytical batch recharacterizes the instrument detector but does not reduce the actual variability. The analytical response and measurand concentrations should be considered when constructing a calibration curve, along with subsequent use of quality controls to confirm assay performance. It is important to assess the linearity of the calibration curve by using actual experimental data and appropriate statistics. The heteroscedasticity of the calibration data should be investigated, and appropriate weighting should be applied during regression modeling. Conclusions This review provides an outline and guidance for optimal calibration practices in clinical mass spectrometry laboratories.

Functional reference limits describe key changes in the physiological relationship between a pair of physiologically related components. Statistically, this can be represented by a significant change in the curvature of a mathematical function or curve (e.g., an observed plateau). The point at which the statistical relationship changes significantly is the point of curvature inflection and can be mathematically modeled from the relationship between the interrelated biomarkers. Conceptually, they reside between reference intervals, which describe the statistical boundaries of a single biomarker within the reference population, and clinical decision limits that are often linked to the risk of morbidity or mortality and set as thresholds. Functional reference limits provide important physiological and pathophysiological insights that can aid laboratory result interpretation. Laboratory professionals are in a unique position to harness data from laboratory information systems to derive clinically relevant values. Increasing research on and reporting of functional reference limits in the literature will enhance their contribution to laboratory medicine and widen the evidence base used in clinical decision limits, which are currently almost exclusively contributed to by clinical trials. Their inclusion in laboratory reports will enhance the intellectual value of laboratory professionals in clinical care beyond the statistical boundaries of a healthy reference population and pave the way to them being considered in shaping clinical decision limits. This review provides an overview of the concepts related to functional reference limits, clinical examples of their use, and the impetus to include them in laboratory reports.

Meningioma associated with intratumoral hemorrhage is rarely reported. We present two patients with intratumoral hemorrhage. One 70-year-old man was admitted to our department with a decreased level of consciousness and left hemiparesis. CT scan and MRI scan revealed huge tumor with intratumoral hemorrhage in the frontal lobe. After surgical removal of the tumor, histopathological diagnosis was a meningotheliomatous meningioma. The other seemed patients was 56-year-old woman with headache and vomiting. She showed no specific neurological deficit. CT and MRI scan revealed large size tumor with intratumoral hemorrhage that looks like meningioma. The patient died suddenly before surgery. We reviewed the relevant literature and discussed the possible mechanism of hemorrhage in the meningioma.
Aged ; Consciousness ; Diagnosis ; Female ; Frontal Lobe ; Headache ; Hemorrhage* ; Humans ; Magnetic Resonance Imaging ; Meningioma* ; Middle Aged ; Paresis ; Tomography, X-Ray Computed ; Vomiting

Four cases of primary transitional cell carcinoma (TCC) arising in the ovary (3 cases) and the parovarium (1 case) were collected for clinicopathologic analysis. The mean age was 46.2 years (range, 39-57 years). Two patients complained abdominal discomfort and vaginal discharge, respectively. Other 2 cases were incidentally found from routine check. Grossly, the tumors were solid and cystic (2 cases), solid (1 case) and surface papillary growth on capsule (1 case). Microscopically, the tumor showed almostly same to the histologic features of TCC of urinary bladder. Three cases were pure TCC, and one was mixed TCC and serous carcinoma. FIGO stage were 1 IIa, 2 IIc, and 1 IIIc. Treatment was surgery with adjuvant chemotherapy. Two patients are alive with no evidence of disease, and two have lung or brain metastasis.
Brain ; Carcinoma, Transitional Cell* ; Chemotherapy, Adjuvant ; Female ; Humans ; Lung ; Neoplasm Metastasis ; Ovary ; Urinary Bladder ; Vaginal Discharge

PTEN (phosphatase and tensin homolog) is a dual specific phosphatase antagonizing phosphoinositide 3-kinase activity, and has first been cloned as a tumor suppressor for glioma. Although the role of PTEN as a tumor suppressor has been well studied, little is known about signaling mechanisms regulating expression and/or activity of PTEN in the central nervous system. In this study, we investigated whether PTEN expression is regulated by sensory deprivation. P5 rat pups were unilaterally naris-closed, and olfactory bulbs were immunohistochemically analyzed with PTEN antibody at the 7th day after naris closure. PTEN immunoreactivity was found to be down-regulated in both glomerular, external plexiform and subependymal cell layers, suggesting that odor deprivation signals down-regulate expression of PTEN in the olfactory bulb. To the best of our knowledge, this is the first report to suggest that PTEN expression is regulated by sensory deprivation signals in neonatal rats.
Animals ; Central Nervous System ; Clone Cells ; Glioma ; Odors ; Olfactory Bulb* ; Rats* ; Sensory Deprivation

Kainic acid (KA) is a structural analogue of glutamate that interacts with specific presynaptic and postsynaptic receptors to potentiate the release and excitatory actions of glutamate. Systemic or intracerebroventricular (i.c.v.) administration of KA to experimental animals elicits multifocal seizures with a predominantly limbic localization, and results in neuronal death of cornu ammonia 1 (CA1), reactive gliosis and biochemical changes in the hippocampus and other limbic structures. Several lines of evidence suggest that reactive oxygen species (ROS) play a pivotal role in the pathogenesis of excitotoxic death by KA. Curcumin has been known to possess anti-oxidative and anti-inflammatory activities. In this study, the effects of curcumin on KA induced hippocampal cell death, reactive gliosis and biochemical changes in reactive glia were investigated by immunohistochemical methods. Our data demonstrated that curcumin attenuated KA-induced astroglial and microglial activation although it did not protect KA-induced hippocampal cell death.
Ammonia ; Animals ; Astrocytes ; Cell Death* ; Curcumin* ; Gliosis ; Glutamic Acid ; Hippocampus ; Kainic Acid ; Microglia ; Neuroglia* ; Neurons* ; Reactive Oxygen Species ; Seizures

Patient-based real-time QC (PBRTQC) uses patient-derived data to assess assay performance. PBRTQC algorithms have advanced in parallel with developments in computer science and the increased availability of more powerful computers. The uptake of Artificial Intelligence in PBRTQC has been rapid, with many stated advantages over conventional approaches. However, until this review, there has been no critical comparison of these. The PBRTQC algorithms based on moving averages, regression-adjusted real-time QC, neural networks and anomaly detection are described and contrasted. As Artificial Intelligence tools become more available to laboratories, user-friendly and computationally efficient, the major disadvantages, such as complexity and the need for high computing resources, are reduced and become attractive to implement in PBRTQC applications.

Patient-based real-time QC (PBRTQC) uses patient-derived data to assess assay performance. PBRTQC algorithms have advanced in parallel with developments in computer science and the increased availability of more powerful computers. The uptake of Artificial Intelligence in PBRTQC has been rapid, with many stated advantages over conventional approaches. However, until this review, there has been no critical comparison of these. The PBRTQC algorithms based on moving averages, regression-adjusted real-time QC, neural networks and anomaly detection are described and contrasted. As Artificial Intelligence tools become more available to laboratories, user-friendly and computationally efficient, the major disadvantages, such as complexity and the need for high computing resources, are reduced and become attractive to implement in PBRTQC applications.

Patient-based real-time QC (PBRTQC) uses patient-derived data to assess assay performance. PBRTQC algorithms have advanced in parallel with developments in computer science and the increased availability of more powerful computers. The uptake of Artificial Intelligence in PBRTQC has been rapid, with many stated advantages over conventional approaches. However, until this review, there has been no critical comparison of these. The PBRTQC algorithms based on moving averages, regression-adjusted real-time QC, neural networks and anomaly detection are described and contrasted. As Artificial Intelligence tools become more available to laboratories, user-friendly and computationally efficient, the major disadvantages, such as complexity and the need for high computing resources, are reduced and become attractive to implement in PBRTQC applications.