Proanthocyanidin B_2(PAC-B_2), a polyphenolic dimeric compound comprising two epicatechin molecules linked by a C-C bond, is extensively found in traditional Chinese medicines, with anti-tumor and anti-oxidant activities. Given the limited bioavailability, a thorough investigation and comprehensive understanding of PAC-B_2 metabolism in vivo are essential for elucidating therapeutic forms and mechanisms. In the present study, ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) in the negative ion mode was employed to acquire the MS/MS information of PAC-B_2 and metabolites in urine and feces samples of the rats administrated with PAC-B_2. Online energy-resolved MS(ER-MS) was applied as supplementary to obtain the full collision energy ramp-MS~2 spectra(FCER-MS~2) of isomers-of-interest, which implied comprehensive MS~2 information of targeted compounds. Finally, the possible metabolic pathways of PAC-B_2 in rats were proposed. The primary fragmentation behaviors of PAC-B_2 in the negative ion mode included quinone methide fission between C_4-C_8 bond, retro Diels-Alder cracking of F-ring, heterocyclic ring fission of C-ring, and neutral loss of small molecules such as H_2O. A total of 25 metabolites were tentatively elucidated in urine and feces samples of rats administrated with PAC-B_2 by fragmentation pattern and reported literature. Two groups of isomers, M3/M4/M5 and M9/M11, were confirmatively differentiated based on the relationships between optimal collision energy provided by FCER-MS~2 and bond properties, including bond length and bond dissociation energy. In addition to the ring-opening and methylation, PAC-B_2 could also be metabolized into epicatechin and low molecular weight phenolic acids, which were subsequently subjected to dehydroxylation, ring-opening, methylation, sulfation, and glucuronidation. The structural information provided by online ER-MS and FCER-MS~2 enabled the differentiation of isomers and improved the identification confidence. More importantly, the present study deeply analyzes the in vivo metabolic pathways of PAC-B_2, providing a basis for the research on the pharmacological mechanism of this compound.
Animals ; Proanthocyanidins/urine* ; Rats ; Male ; Drugs, Chinese Herbal/chemistry* ; Rats, Sprague-Dawley ; Tandem Mass Spectrometry ; Chromatography, High Pressure Liquid ; Feces/chemistry* ; Molecular Structure

Oncological microdissection testicular sperm extraction (onco-micro-TESE) represents a significant breakthrough for patients with nonobstructive azoospermia (NOA) and a concomitant in situ testicular tumor, to be managed at the time of sperm retrieval. Onco-micro-TESE addresses the dual objectives of treating both infertility and the testicular tumor simultaneously. The technique is intricate, necessitating a comprehensive understanding of testicular anatomy, physiology, tumor biology, and advanced microsurgical methods. It aims to carefully extract viable spermatozoa while minimizing the risk of tumor dissemination. This review encapsulates the procedural intricacies, evaluates success determinants, including tumor pathology and spermatogenic tissue health, and discusses the implementation of imaging techniques for enhanced surgical precision. Ethical considerations are paramount, as the procedure implicates complex decision-making that weighs the potential oncological risks against the profound desire for fatherhood using the male gametes. The review aims to provide a holistic overview of onco-micro-TESE, detailing methodological advances, clinical outcomes, and the ethical landscape, thus offering an indispensable resource for clinicians navigating this multifaceted clinical scenario.
Humans ; Male ; Azoospermia/therapy* ; Testicular Neoplasms/pathology* ; Sperm Retrieval ; Microdissection/methods* ; Testis/surgery*

OBJECTIVES: To investigate the role and mechanism of copper overload-mediated endoplasmic reticulum stress (ERS) in vascular endothelial injury in Kawasaki disease (KD). METHODS: Four-week-old male C57BL/6 mice were randomly divided into four groups: control, KD, KD plus copper chelator tetrathiomolybdate (TTM), and KD plus ERS inhibitor AMG PERK 44 (AMG) (n=20 per group). A KD mouse model was established using Candida albicans extract. Human umbilical vein endothelial cells (HUVECs) were divided into control (intervention with healthy children's serum), KD (intervention with KD patients' serum), and KD+TTM (intervention with KD patients' serum plus 20 µmol/L TTM). Copper deposition in mouse heart tissue was assessed using rubeanic acid staining. Vascular pathological changes were observed using hematoxylin-eosin staining and measurement of abdominal aortic diameter and area. ERS activation was detected by transmission electron microscopy and immunofluorescence. HUVEC viability, apoptosis, and functional changes were evaluated using CCK8, flow cytometry, cell scratch assay, and angiogenesis experiments. ERS marker protein expression levels were measured by Western blot. RESULTS: Compared to the KD group, the KD+TTM and KD+AMG groups showed reduced copper deposition in the vascular wall, decreased swelling of coronary endothelial cells and endoplasmic reticulum, reduced inflammatory cell infiltration, and less abdominal aortic lesion expansion. The abdominal aortic diameter and area, and the fluorescence intensity of ERS marker proteins (GRP78 and CHOP) were significantly lower (P<0.05). Compared to the KD group, the KD+TTM group exhibited increased cell viability, tube number, and scratch healing rate, along with decreased apoptosis rate and expression of ERS marker proteins (GRP78, CHOP, ATF6, and p-PERK) (P<0.05). CONCLUSIONS Copper overload aggravates vascular endothelial injury in KD by activating the ERS pathway. TTM can exert protective effects on the endothelium by regulating copper metabolism and inhibiting the ERS pathway.
Endoplasmic Reticulum Stress ; Copper/toxicity* ; Male ; Mucocutaneous Lymph Node Syndrome/metabolism* ; Animals ; Humans ; Endoplasmic Reticulum Chaperone BiP ; Mice, Inbred C57BL ; Mice ; Human Umbilical Vein Endothelial Cells ; Apoptosis ; Endothelium, Vascular/injuries*

OBJECTIVE: To explore the effect of chitosan (CS) hydrogel loaded with tendon-derived stem cells (TDSCs; hereinafter referred to as TDSCs/CS hydrogel) on tendon-to-bone healing after rotator cuff repair in rabbits. METHODS: TDSCs were isolated from the rotator cuff tissue of 3 adult New Zealand white rabbits by Henderson step-by-step enzymatic digestion method and identified by multidirectional differentiation and flow cytometry. The 3rd generation TDSCs were encapsulated in CS to construct TDSCs/CS hydrogel. The cell counting kit 8 (CCK-8) assay was used to detect the proliferation of TDSCs in the hydrogel after 1-5 days of culture in vitro, and cell compatibility of TDSCs/CS hydrogel was evaluated by using TDSCs alone as control. Another 36 adult New Zealand white rabbits were randomly divided into 3 groups ( n=12): rotator cuff repair group (control group), rotator cuff repair+CS hydrogel injection group (CS group), and rotator cuff repair+TDSCs/CS hydrogel injection group (TDSCs/CS group). After establishing the rotator cuff repair models, the corresponding hydrogel was injected into the tendon-to-bone interface in the CS group and TDSCs/CS group, and no other treatment was performed in the control group. The general condition of the animals was observed after operation. At 4 and 8 weeks, real-time quantitative PCR (qPCR) was used to detect the relative expressions of tendon forming related genes (tenomodulin, scleraxis), chondrogenesis related genes (aggrecan, sex determining region Y-related high mobility group-box gene 9), and osteogenesis related genes (alkaline phosphatase, Runt-related transcription factor 2) at the tendon-to-bone interface. At 8 weeks, HE and Masson staining were used to observe the histological changes, and the biomechanical test was used to evaluate the ultimate load and the failure site of the repaired rotator cuff to evaluate the tendon-to-bone healing and biomechanical properties. RESULTS: CCK-8 assay showed that the CS hydrogel could promote the proliferation of TDSCs ( P<0.05). qPCR results showed that the expressions of tendon-to-bone interface related genes were significantly higher in the TDSCs/CS group than in the CS group and control group at 4 and 8 weeks after operation ( P<0.05). Moreover, the expressions of tendon-to-bone interface related genes at 8 weeks after operation were significantly higher than those at 4 weeks after operation in the TDSCs/CS group ( P<0.05). Histological staining showed the clear cartilage tissue and dense and orderly collagen formation at the tendon-to-bone interface in the TDSCs/CS group. The results of semi-quantitative analysis showed that compared with the control group, the number of cells, the proportion of collagen fiber orientation, and the histological score in the TDSCs/CS group increased, the vascularity decreased, showing significant differences ( P<0.05); compared with the CS group, the proportion of collagen fiber orientation and the histological score in the TDSCs/CS group significantly increased ( P<0.05), while there was no significant difference in the number of cells and vascularity ( P>0.05). All samples in biomechanical testing failed at the repair site during the testing process. The ultimate load of the TDSCs/CS group was significantly higher than that of the control group ( P<0.05), but there was no significant difference compared to the CS group ( P>0.05). CONCLUSION TDSCs/CS hydrogel can induce cartilage regeneration to promote rotator cuff tendon-to-bone healing.
Rabbits ; Animals ; Rotator Cuff/surgery* ; Chitosan ; Hydrogels ; Rotator Cuff Injuries/surgery* ; Wound Healing ; Tendons/surgery* ; Collagen ; Stem Cells ; Biomechanical Phenomena