Mitochondrial dehydrogenases are differentially stimulated by Ca²⁺. Ca²⁺ has also diverse regulatory effects on mitochondrial transporters and other enzymes. However, the consequences of these regulatory effects on mitochondrial oxidative phosphorylation (OxPhos) and ATP production, and the dependencies of these consequences on respiratory substrates, have not been investigated between the kidney and heart despite the fact that kidney energy requirements are second only to those of the heart. Our objective was, therefore, to elucidate these relationships in isolated mitochondria from the kidney outer medulla (OM) and heart. ADP-induced mitochondrial respiration was measured at different CaCl₂ concentrations in the presence of various respiratory substrates, including pyruvate + malate (PM), glutamate + malate (GM), alpha-ketoglutarate + malate (AM), palmitoyl-carnitine + malate (PCM), and succinate + rotenone (SUC + ROT). The results showed that, in both heart and OM mitochondria, and for most complex I substrates, Ca²⁺ effects are biphasic: small increases in Ca²⁺ concentration stimulated, while large increases inhibited mitochondrial respiration. Furthermore, significant differences in substrate- and Ca²⁺-dependent O₂ utilization towards ATP production between heart and OM mitochondria were observed. With PM and PCM substrates, Ca²⁺ showed more prominent stimulatory effects in OM than in heart mitochondria, while with GM and AM substrates, Ca²⁺ had similar biphasic regulatory effects in both OM and heart mitochondria. In contrast, with complex II substrate SUC + ROT, only inhibitory effects on mitochondrial respiration was observed in both the heart and the OM. We conclude that the regulatory effects of Ca²⁺ on mitochondrial OxPhos and ATP synthesis are biphasic, substrate-dependent, and tissue-specific.

Visual inspection via laparoscopy is considered the gold standard for the diagnosis of deep infiltrating endometriosis. Laparoscopy is an invasive procedure; therefore, it would be beneficial to patients if accurate non‑invasive modalities were available for the diagnosis of deep infiltrating endometriosis. The purpose of the current review and meta‑analysis was to assess the diagnostic accuracy of clinical examination, transvaginal ultrasound (TVUS), transrectal ultrasound (TRUS) and MRI as alternative methods for diagnosis of deep infiltrating endometriosis. A systematic search of the Medline, Scopus, Embase and Cochrane library databases, between their inception and September 2019, was performed. The quality of trials was assessed using the quality assessment of diagnostic accuracy studies‑2 tool. Meta‑analyses were conducted to obtain the pooled sensitivity, specificity, positive and negative likelihood ratios and diagnostic odds ratio for each of the three imaging modalities and clinical examination. A total of 30 studies with 4,565 participants were included in the review. Physical examination had a pooled sensitivity of 71% and a specificity of 69%, with an average diagnostic accuracy [area under the curve (AUC) =0.76]. TVUS had a pooled sensitivity of 76% and a specificity of 94%, with higher diagnostic accuracy than physical examination (AUC =0.92). TRUS had a pooled sensitivity of 91% and a specificity of 80% with an AUC of 0.93. MRI had a pooled sensitivity of 82% and a specificity of 87% with higher diagnostic accuracy than physical examination (AUC =0.91). All the imaging modalities had good clinical utility, as indicated by the Fagan plot. The present analysis demonstrates that the imaging modalities TVUS, TRUS and MRI may be highly useful alternatives to laparoscopy for diagnosis of deep infiltrating endometriosis and that these techniques have a high sensitivity and specificity.

X-ray computed tomography (XCT) and X-ray fluorescence (XRF) imaging are two non-invasive imaging techniques to study cellular structures and chemical element distributions, respectively. However, correlative X-ray computed tomography and fluorescence imaging for the same cell have yet to be routinely realized due to challenges in sample preparation and X-ray radiation damage. Here we report an integrated experimental and computational workflow for achieving correlative multi-modality X-ray imaging of a single cell. The method consists of the preparation of radiation-resistant single-cell samples using live-cell imaging-assisted chemical fixation and freeze-drying procedures, targeting and labeling cells for correlative XCT and XRF measurement, and computational reconstruction of the correlative and multi-modality images. With XCT, cellular structures including the overall structure and intracellular organelles are visualized, while XRF imaging reveals the distribution of multiple chemical elements within the same cell. Our correlative method demonstrates the feasibility and broad applicability of using X-rays to understand cellular structures and the roles of chemical elements and related proteins in signaling and other biological processes.

Segmentation of three-dimensional (3D) cellular images is fundamental for studying and understanding cell structure and function. However, 3D cellular segmentation is challenging, particularly for dense cells and tissues. This challenge arises mainly from the complex contextual information within 3D images, anisotropic properties, and the sensitivity to internal cellular structures, which often lead to incorrect segmentation. In this work, we introduce SwinCell, a 3D transformer-based framework that leverages Swin-transformer to predict flow and differentiate individual cell instances. We demonstrate SwinCell’s utility in the segmentation of nuclei, colon tissue cells, and densely cultured cells. SwinCell strikes a balance between maintaining detailed local feature recognition and understanding broader contextual information. Through extensive testing with both public and in-house 3D cell imaging datasets, SwinCell shows utility in segmenting dense cells, making it a valuable tool for 3D segmentation in cellular analysis that could expedite research in cell biology and tissue engineering.