Intravenous administration of vesicants or irritants frequently leads to chemical phlebitis. We aimed to establish a chemical phlebitis rat model by injection vinorelbine via dorsal pedal vein and evaluate the general symptoms as well as the pathological features of lesion venous tissues. Rats in 6 groups with each 8 were injected 0.1 mL saline or vinorelbine (1-5 mg/mL) via the dorsalis pedis vein in hind paw, respectively. The edema and pain were assessed daily by swelling rates (water displacement) and weight-bearing ratio (bipedal balance test), respectively. Phlebitis severity was evaluated by phlebitis scale. Venous tissues harvested on day 7 were underwent histopathological and ultrastructural evaluation. Vinorelbine administration elicited dose-dependent inflammatory responses, with erythema, edema, pain, palpable cord formation, and purulent drainage. Edema and pain peaked on day 3, as evidenced by increased swelling rates and reduced weight-bearing ratios. Persistent symptomatology was observed in the 3-5 mg/mL groups through day 7. Histopathological analysis demonstrated venous wall thickening characterized by intimal hyperplasia and collagen deposition, along with vascular lumen stenosis accompanied by thrombosis. Furthermore, disruption of the intimal lining was observed, with shrunken endothelial cells interspersed among extracellular matrix. These pathological changes also exhibited a dose-dependent exacerbation with increasing concentrations of vinorelbine. Dorsal pedal vein injection of 0.1 mL vinorelbine (3-5 mg/mL) successfully induced chemical phlebitis in rats, mimicking human clinical presentations. Furthermore, vinorelbine-induced endothelial damage resulted in distinct venous lesions, characterized by vascular wall thickening with intimal hyperplasia, luminal stenosis and thrombus.

Cerebrovascular disease is a prevalent condition among the elderly, with its incidence steadily rising. The basilar artery is a critical cerebral vessel that supplies the pons, cerebellum, posterior brain regions, and inner ear. Potassium (K+) channel activity plays a significant role in determining vascular tone by regulating the cell membrane potential. Activation of inward rectifying K+ (Kir) channels, like other K+ channels, leads to cell membrane hyperpolarization and vasodilation. In this study, freshly isolated smooth muscle cells from the basilar artery were used to record Kir currents via the whole-cell patch clamp technique. The effects of 100 µmol/L BaCl2, a Kir channel inhibitor, and 10 µmol/L sodium nitroprusside (SNP), a nitro vasodilator, on Kir channel currents were investigated. The results demonstrated that BaCl2 inhibited Kir channel currents in basilar artery smooth muscle cells, whereas SNP enhanced these currents. This protocol provides a comprehensive guide for preparing freshly isolated arterial smooth muscle cells and recording Kir channel currents using the patch clamp technique, offering a valuable resource for researchers seeking to master this method.

Background: Despite limited research on refractory and/or endocrine therapy failure in elderly metastatic breast cancer (MBC) patients, a prior study did show that low-dose oral cyclophosphamide (CY) can improve the overall survival rate of MBC, possibly through immunoregulation of regulatory T cells (Tregs). We performed a preliminary investigation of the combination of endocrine therapy (ET) with oral low-dose CY as salvage therapy in elderly patients with peripheral blood regulatory T cell analyses. In addition, we evaluated the association of tumor tertiary lymphoid structures (TLSs) with therapeutic outcomes. Patients and Methods: HR+/HER2˗ advanced breast cancer patients who received low-dose CY combined with ET or ET only from April 2015 to August 2021 were enrolled in this retrospective study. The primary outcome was the clinical control rate (CCR), and the secondary outcome was progression-free survival (PFS). Circulating T lymphocyte subpopulations represented by Tregs were monitored during treatment by flow cytometry methods. TLS diagnosis was confirmed by hematoxylin–eosin staining of pretreatment specimens, and CD3, CD4, and Foxp3 were stained using Opal multicolor immunofluorescence. Results:85 patients received CY + ET and 50 patients received ET only were enrolled, CCR was 73% (62/85) vs. 70% (45/50), and objective response rate (ORR) was 28% (24/85) vs. 24% (12/50). No deaths occurred during the study period. The median PFS time was 13 vs. 11 months (P = 0.03). In the CY + ET group, the decreases in CD4+/CD25+/Foxp3+ T cells (P<0.001) were favorable for both clinical control and prolonged PFS (P < 0.001), compared with patients without TLSs, those with TLSs were more likely to have better clinical control and PFS (mean time=6 months), and a higher level of Treg cells in TLSs pretreatment correlated with longer PFS (P=0.043). Conclusions: Oral low-dose CY combined with standard ET exerts immunological regulation by decreasing Treg to achieve improved clinical responses. Moreover, patients with TLSs might benefit more from such therapy than those without TLSs, and a high Treg count in TLSs before treatment predicts better therapy efficacy.

The vasodilator effect of apigenin (API) was demonstrated in a number of vascular beds. We aimed to characterize the vasospasmolytic and electrophysiological effects of apigenin (API) in intrarenal arteries (IRAs). The vascular tone of male rat isolated IRAs was recorded with a myograph. Transmembrane Cl ⁻ currents through Ca ²⁺ -activated Cl ⁻ channels (CaCCs), K ⁺ currents through voltage-gated K ⁺ (Kv) channels and inwardly rectifier K ⁺ (Kir) channels were recorded with patch clamp in the freshly isolated arterial smooth muscle cells (ASMCs). Preincubation with API (10-100 μM) concentration-dependently depressed the contractions induced by KCl, 9,11-dideoxy-9α,11α-methanoepoxy prostaglandin F _2α (U46619), phenylephrine and vasopressin without significant preference and the IC ₅₀ values were 13.27-26.26 μM. Acute application of API elicited instant relaxations in the IRAs precontracted with these vasoconstrictors and the RC ₅₀ values were 5.80-24.33 μM. API relaxation was attenuated by chloride deprivation, CaCC blockers, Kv blocker and nitric oxide synthase inhibitor, but not by Kir blocker and cyclooxygenase inhibitor. At 10-100 μM, API depressed CaCC currents and Kir currents while enhanced Kv currents of IRA ASMCs. The present results demonstrate that API counteracts various vasoconstrictors noncompetitively and nonspecifically and suggest that modulation of CaCCs, Kv and Kir channels of IRA ASMCs is involved in its vasospasmolytic effects.

Cerebrovascular disease is a prevalent condition among the elderly, with its incidence steadily rising. The basilar artery is a critical cerebral vessel that supplies the pons, cerebellum, posterior brain regions, and inner ear. Potassium (K+) channel activity plays a significant role in determining vascular tone by regulating the cell membrane potential. Activation of inward rectifying K+ (Kir) channels, like other K+ channels, leads to cell membrane hyperpolarization and vasodilation. In this study, freshly isolated smooth muscle cells from the basilar artery were used to record Kir currents via the whole-cell patch clamp technique. The effects of 100 µmol/L BaCl2, a Kir channel inhibitor, and 10 µmol/L sodium nitroprusside (SNP), a nitro vasodilator, on Kir channel currents were investigated. The results demonstrated that BaCl2 inhibited Kir channel currents in basilar artery smooth muscle cells, whereas SNP enhanced these currents. This protocol provides a comprehensive guide for preparing freshly isolated arterial smooth muscle cells and recording Kir channel currents using the patch clamp technique, offering a valuable resource for researchers seeking to master this method.