Consistency analysis of the Sysmex UF-5000 and Atellica UAS 800 urine sedimentation analyzers.

OBJECTIVE: To evaluate the consistency between the results of Sysmex UF-5000 system and Atellica® UAS 800 Urine Sediment Analyzer. METHODS: A total of 636 random urine samples were collected from inpatients and outpatients from March to September 2021. Urine was collected for analysis by the Sysmex UF-5000, Atellica UAS 800 systems, and manual microscopic examination. The results of manual microscopy as the gold standard, the coincidence rate and false-negative rate of Sysmex UF-5000 and Atellica UAS 800 systems in the detection of red blood cells, white blood cells, and casts were calculated. RESULTS: The coincidence rates of red blood cells, white blood cells, and cast, crystals, and other sediment components for the Sysmex UF-5000 system were 85.37%, 87.89%, 91.67%, 88.36%, and 71.86%. The false-negative rates were 28.47%, 3.75%, 68.97%, 37.25%, and 30.63%. The coincidence rates of red blood cells, white blood cells, and cast, crystals, and other sediment components for the Atellica UAS 800 system were 85.06%, 90.25%, 59.12%, 91.67%, and 67.45% and the false-negative rates were 60.42%, 21.25%, 36.21%, 19.64%, and 35.80%. CONCLUSION: Two instruments are superior in the detection of red blood cells and white blood cells. The Atellica UAS 800 system with image review has a good coincidence rate in the identification of crystals and casts. The identification of various sediment components in urine by both instruments meets the laboratory requirements. Two instruments with different methodologies have their own characteristics, and we should reasonably use them according to the conditions of the laboratory.

Characterization of a mouse model of headache.

Migraine and other primary headache disorders affect a large population and cause debilitating pain. Establishing animal models that display behavioral correlates of long-lasting and ongoing headache, the most common and disabling symptom of migraine, is vital for the elucidation of disease mechanisms and identification of drug targets. We have developed a mouse model of headache, using dural application of capsaicin along with a mixture of inflammatory mediators (IScap) to simulate the induction of a headache episode. This elicited intermittent head-directed wiping and scratching as well as the phosphorylation of c-Jun N-terminal kinase in trigeminal ganglion neurons. Interestingly, dural application of IScap preferentially induced FOS protein expression in the excitatory but not inhibitory cervical/medullary dorsal horn neurons. The duration of IScap-induced behavior and the number of FOS-positive neurons correlated positively in individual mice; both were reduced to the control level by the pretreatment of antimigraine drug sumatriptan. Dural application of CGRP(8-37), the calcitonin gene-related peptide (CGRP) receptor antagonist, also effectively blocked IScap-induced behavior, which suggests that the release of endogenous CGRP in the dura is necessary for IScap-induced nociception. These data suggest that dural IScap-induced nocifensive behavior in mice may be mechanistically related to the ongoing headache in humans. In addition, dural application of IScap increased resting time in female mice. Taken together, we present the first detailed study using dural application of IScap in mice. This headache model can be applied to genetically modified mice to facilitate research on the mechanisms and therapeutic targets for migraine headache.

TGF-beta1 induces the different expressions of lysyl oxidases and matrix metalloproteinases in anterior cruciate ligament and medial collateral ligament fibroblasts after mechanical injury.

The anterior cruciate ligament (ACL) is known to have a poor self-healing ability. In contrast, the medial collateral ligament (MCL) can heal relatively well and restore the joint function. Transforming growth factor-beta1 (TGF-ß1) is considered to be an important chemical mediator in the wound healing of the ligaments. While the role of TGF-ß1-induced expressions of the lysyl oxidases (LOXs) and matrix metalloproteinases (MMPs), which respectively facilitate the extracellular matrix (ECM) repair and degradation, is poorly understood. In this study, we used equibiaxial stretch chamber to mimic mechanical injury of ACL and MCL fibroblasts, and aimed to determine the intrinsic differences between ACL and MCL by characterizing the differential expressions of LOXs and MMPs in response to TGF-ß1 after mechanical injury. By using semi-quantitative PCR, quantitative real-time PCR, western blot and zymography, we found TGF-ß1 induced injured MCL to express more LOXs than injured ACL (up to 1.85-fold in LOX, 2.21-fold in LOXL-1, 1.71-fold in LOXL-2, 2.52-fold in LOXL-3 and 3.32-fold in LOXL-4). Meanwhile, TGF-ß1 induced injured ACL to express more MMPs than injured MCL fibroblasts (up to 2.33-fold in MMP-1, 2.45-fold in MMP-2, 1.89-fold in MMP-3 and 1.50-fold in MMP-12). The further protein results were coincident with the gene expressions above. The different expressions of LOXs and MMPs inferred the intrinsic differences between ACL and MCL, and the intrinsic differences could help to explain their differential healing abilities.

Expression of the transient receptor potential channels TRPV1, TRPA1 and TRPM8 in mouse trigeminal primary afferent neurons innervating the dura.

BACKGROUND: Migraine and other headache disorders affect a large percentage of the population and cause debilitating pain. Activation and sensitization of the trigeminal primary afferent neurons innervating the dura and cerebral vessels is a crucial step in the "headache circuit". Many dural afferent neurons respond to algesic and inflammatory agents. Given the clear role of the transient receptor potential (TRP) family of channels in both sensing chemical stimulants and mediating inflammatory pain, we investigated the expression of TRP channels in dural afferent neurons. METHODS: We used two fluorescent tracers to retrogradely label dural afferent neurons in adult mice and quantified the abundance of peptidergic and non-peptidergic neuron populations using calcitonin gene-related peptide immunoreactivity (CGRP-ir) and isolectin B4 (IB4) binding as markers, respectively. Using immunohistochemistry, we compared the expression of TRPV1 and TRPA1 channels in dural afferent neurons with the expression in total trigeminal ganglion (TG) neurons. To examine the distribution of TRPM8 channels, we labeled dural afferent neurons in mice expressing farnesylated enhanced green fluorescent protein (EGFPf) from a TRPM8 locus. We used nearest-neighbor measurement to predict the spatial association between dural afferent neurons and neurons expressing TRPA1 or TRPM8 channels in the TG. RESULTS AND CONCLUSIONS: We report that the size of dural afferent neurons is significantly larger than that of total TG neurons and facial skin afferents. Approximately 40% of dural afferent neurons exhibit IB4 binding. Surprisingly, the percentage of dural afferent neurons containing CGRP-ir is significantly lower than those of total TG neurons and facial skin afferents. Both TRPV1 and TRPA1 channels are expressed in dural afferent neurons. Furthermore, nearest-neighbor measurement indicates that TRPA1-expressing neurons are clustered around a subset of dural afferent neurons. Interestingly, TRPM8-expressing neurons are virtually absent in the dural afferent population, nor do these neurons cluster around dural afferent neurons. Taken together, our results suggest that TRPV1 and TRPA1 but not TRPM8 channels likely contribute to the excitation of dural afferent neurons and the subsequent activation of the headache circuit. These results provide an anatomical basis for understanding further the functional significance of TRP channels in headache pathophysiology.

The mirror-image pain: an unclered phenomenon and its possible mechanism.

The contralateral allodynia to an injury has been described both in humans and various models of neuropathic and inflammatory pain in rats. In this article, the occurrence of mirror-image pain (MIP) in human beings and animals were reviewed and the possible mechanism of MIP reported was summarized. Last, according to the literature published, we raise some speculation about the possible mechanism underlying MIP.

Roles of TRESK, a novel two-pore domain K+ channel, in pain pathway and general anesthesia.

TRESK is the most recently reported two-pore domain K+ channel, and different from other two-pore domain channels in gene, molecular structure, electrophysiological and pharmacological properties. Although the current knowledge of this potassium channel is inadequate, researches have demonstrated that TRESK is remarkablely linked to acute and chronic pain by activation of calcineurin. The fact that TRESK is sensitive to volatile anesthetics and localization in central nerve system implies that TRESK may play a very important role in the mechanism mediating general anesthesia. The further research of TRESK may contribute to explore the underlying mechanism of some pathological conditions and yield novel treatments for some diseases.

Recent advance and possible future in TREK-2: a two-pore potassium channel may involved in the process of NPP, brain ischemia and memory impairment.

TREK-2, a new member of the mechanosensitive tandem-pore K+ channel family, share 65% amino acid sequence identity and some similar basic electrophysiological and pharmacological properties with TREK-1. It also has some specific regulatory pathway and tissue distribution contrasted with TREK-1 and TRAAK. TREK-2 distributes extensively in CNS and periphery tissue. It can be regulated by G-protein-coupled receptor (GPCR) and may involve in several of physiological and pathophysiological conditions. The long-chain unsaturated free fatty acids such as arachidonic acid (AA), PHi, pressure and temperature can increase the activity of TREK-2. The purpose of this review is to present the recent study and possible importance of TREK-2 in neuropathic pain, thereby emphasizing TREK-2 as one of the important mechanisms underlying. This information should be very useful and prospective for effective chronic pain therapy and future analgesic drug development. This review also further predicts the role of TREK-2 in brain ischemia, memory and other tissue. The specific location and function of TREK-2 in these tissues need further study.