Reaction mechanism of nanomedicine based on porphyrin skeleton and its application prospects

Research on porphyrin-based photosensitizing drugs is becoming increasingly popular. They possess unique diagnostic capabilities and therapeutic effects that have gained wide recognition in oncology drug development. In recent years, the rapid growth of nanotechnology has brought great hope for nanopharmaceutical formulations. By combining porphyrins with various nanomaterials, people have improved the properties of porphyrin compounds, making drug delivery easier. Porphyrin-based nanoparticles can enhance the effect of photodynamic therapy for cancer treatment, providing opportunities for achieving complex targeting strategies and versatility with promising applications in drug carriers, tumor imaging, and treatment. This paper reviews recent porphyrin nanodrugs, including inorganic-organic hybrid nanoparticles, nanomicelles, self-assembled nanoparticles, and combination therapeutic nanodrugs, and their actions and effects on cancer cells when performing photodynamic therapy. It also discusses the drawbacks as well as the prospects for development.

[Establishment of patient-derived salivary gland basal cell adenoma organoids]

Objective: To establish an in vitro organoid model of human salivary gland basal cell adenoma (BCA). Methods: Fresh tumor sample from a 66-year-old female patient diagnosed with salivary gland BCA was collected from the Dpartment of Oral pathology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine in October 2021. And the organoid culture was performed in vitro in a culture medium based on solid droplets of matrix gel, and the growth of the organoid was observed by inverted microscopy. After 14 days, the organoid was fixed in 10% neutral formalin and made into paraffin blocks by agar pre-embedding paraffin embedding method, sectioned. HE staining, morphological observation and immunohistochemical staining of p63, Ki-67, cytokeratin14 (CK14), β-catenin, S-100 and calponin were used for organoids identification. Results: The established BCA organoids were lobulated nodular locally under light microscopy, with deposition of eosinophilic glass-like material around the nests of organoid cells, similar to the morphological architectures of the parental BCA. Immunohistochemistry showed that organoids expressed CK14, p63, and β-catenin in various degree, which was consistent with the immunophenotypic characteristics of the parental BCA tumor cells. Conclusions: An in vitro culture system of BCA organoids was preliminarily established which provides a new model for the study of the pathogenesis of salivary gland tumors.

Porphyrin-Based Nanoparticles: A Promising Phototherapy Platform

Phototherapy, including photodynamic therapy and photothermal therapy, is an emerging form of non-invasive treatment. The combination of imaging technology and phototherapy is becoming an attractive development in the treatment of cancer, as it allows for highly effective therapeutic results through image-guided phototherapy. Porphyrins have attracted significant interest in the treatment and diagnosis of cancer due to their excellent phototherapeutic effects in phototherapy and their remarkable imaging capabilities in fluorescence imaging, magnetic resonance imaging and photoacoustic imaging. However, porphyrins suffer from poor water solubility, low near-infrared absorption and insufficient tumor accumulation. The development of nanotechnology provides an effective way to improve the bioavailability, phototherapeutic effect and imaging capability of porphyrins. This review highlights the research results of porphyrin-based small molecule nanoparticles in phototherapy and image-guided phototherapy in the last decade and discusses the challenges and directions for the development of porphyrin-based small molecule nanoparticles in phototherapy.

Application of metalloporphyrin sensitizers for the treatment or diagnosis of tumors

At present, metalloporphyrin compounds demonstrate three main uses as anticancer sensitizers: (1) photosensitizers, (2) photothermal conversion agents, and (3) ultrasound sensitizers. Developing efficient sensitizers for cancer with excellent controllability and biocompatibility is an important goal of oncology medicine. Because of the different structural diversity of anticancer sensitizers, such sensitizers are used for treating cancers by employing a variety of tumor treatment methods such as mature photodynamic therapy, commonly used clinically photothermal therapy and promising sonodynamic therapy. Among the many sensitizers, metalloporphyrin-complex sensitizers attract wide attention due to their excellent performance in tumor treatment and diagnosis. This review briefly describes some metalloporphyrin anticancer drugs and diagnostic agents related to photodynamic, photothermal and sonodynamic therapy, and discusses the roles of metal atoms in these drugs.

The bipolar charge plasma spectrometer (BCPS) based on the 2π-field-of-view double-channel electrostatic analyzer

In this paper, we propose a bipolar charge plasma spectrometer based on the double-channel electrostatic analyzer for simultaneously measuring thermal ions and electrons with a 2π hemispherical field-of-view. Both ions and electrons within the wide field-of-view enter the spectrometer, pass through the variable geometric factor channel, and are then separated by the double-channel electric fields. Two microchannel plates are accommodated at the exit of the analyzer for ion and electron detection. The main performance of the spectrometer has been obtained from on-ground calibration. With the electrostatic deflectors and the cylindrically symmetric structure, the spectrometer provides simultaneous measurements of thermal ion and electron velocity distributions with a shared field-of-view of 360° (azimuth angle) by 90° (elevation angle) and a broad energy range for both ions and electrons. The ion analyzer constant and the electron analyzer constant are 11.1 and 9.7, respectively. The detecting energy range of 33.3-44.4 keV for ions and 29.1-38.8 keV for electrons can be obtained by using the sweeping electrostatic analyzer voltage range of 3-4000 V. The ion and electron energy resolutions are 9.6% and 6.1%, respectively. The variable geometric factor function provides a large geometric factor adjusting range for both ion and electron measurements by two orders of magnitude, which fulfills the requirements of a large dynamic flux range for simultaneous measurements of space thermal plasma in the solar wind and magnetosphere.

Video-assisted anal fistula treatment for complex anorectal fistulas in adults: a systematic review and meta-analysis

BACKGROUND

Video-assisted anal fistula treatment (VAAFT) has gained increasing acceptance as a sphincter-sparing procedure for treating complex anorectal fistulas (CAF), but no unequivocal conclusions can yet be drawn regarding its ultimate effectiveness. We reviewed the literature and performed a meta-analysis to evaluate the efficacy and safety of VAAFT in CAF patients.

METHODS

The study protocol was registered with the PROSPERO database (CRD42021279085). A systematic literature search was performed in the PubMed, Embase, and Cochrane Library databases up to June 2021 with no restriction on language based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We used the keywords video-assisted surgery, video-assisted anal fistula treatment, and complex anorectal fistula to identify relevant studies.

RESULTS

Fourteen trials (7 prospective and 7 retrospective) with a total of 1201 patients (mean age 43.5 years) were included. The median follow-up duration was 16.5(8-48) months. Pooled analysis showed that the rates of success, recurrence and postoperative complication across the studies were 83% (95% CI 81-85%, I² = 37.9%), 16% (95% CI 14-18%, I² = 4.8%), 11% (95% CI 7-15%, I² = 72.1%), respectively. The postoperative Jorge-Wexner score used to assess the level of anal incontinence was 1.09 (95% CI, 0.9-1.27, I² = 74.6%). The internal opening detection rate was 97.6% (95% CI 96.1-99.6%, I² = 48.2%). Recurrence rates varied according to the closure method of internal opening from 21.4% after using staplers, 18.7% after suturing, to 23.5% after advancement flap. The hospital stay was 3.15 days (95% CI 2.96-3.35, I² = 49.7%). Subgroup analysis indicated that the risk of heterogeneity in the urine retention group was higher  compared with that of the overall group and that retrospective studies may be the source of heterogeneity for postoperative anal incontinence. r . Sensitivity analysis confirmed the stability of the pooled results. Begg's and Egger's tests showed no evidence of publication bias.

CONCLUSIONS

According to the available evidence, VAAFT may be a valuable alternative to fistulotomy or seton in treating CAF and has the additional long-term benefits of reducing anal incontinence and surgical morbidity, permitting earlier healing and accelerated rehabilitation.

Changes in bone mineral density in Down syndrome individuals: a systematic review and meta-analysis

Data evaluating changes in bone mineral density (BMD) in Down syndrome (DS) individuals remains controversial. Therefore, we conducted a systematic review and meta-analysis to better understand associations between BMD and DS. A systematic literature search of PubMed, EMBASE, Web of Science, and the Cochrane Library up until 1st January 2021 was conducted. We used the keywords "bone mineral density" and "Down Syndrome." Fifteen studies were included. Overall, our results showed a significant decrease in BMD of total body (TB BMD) [MD =  - 0.18; 95% CI (- 0.23 and - 0.12), P < 0.00001, I2 = 89%], total hip (TH BMD) [MD =  - 0.12; 95% CI (- 0.15 and - 0.10), P < 0.00001, I2 = 0%], lumbar spine (LS BMD) [MD =  - 0.12; 95% CI (- 0.14 and - 0.09), P < 0.00001, I2 = 18%], and femoral neck (FN BMD) [MD =  - 0.08; 95% CI (- 0.10 and - 0.06), P < 0.00001, I2 = 0%] in DS individuals when compared with controls. Moreover, the volumetric BMD of lumbar spine (LS vBMD) [MD =  - 0.01; 95% CI (- 0.02 and - 0.01), P = 0.0004, I2 = 19%] also showed a decreasing tendency while the volumetric BMD of the femoral neck (FN vBMD) [MD = 0.01; 95% CI (0.00 and 0.02), P = 0.02, I2 = 0%] was elevated in DS individuals versus controls. These findings demonstrated that individuals with DS had a decreased total and regional (TH, LS, and FN) BMD when compared with the general population. Additionally, when BMD was adjusted for skeletal volume, LS vBMD was also lower, while FN vBMD was elevated in DS individuals versus controls.

[Programmed death ligand 1 expression and CD8+T lymphocyte infiltration in salivary gland lymphoepithelial carcinoma]

Objective: To study the expression of programmed death ligand-1 (PD-L1) in tumor cells and CD8⁺T lymphocytes in tumor infiltrating lymphocytes, and to analyze the correlation of PD-L1 expression with infiltration of CD8⁺T lymphocytes and clinicopathologic features in salivary gland lymphoepithelial carcinoma (LEC). Methods: Forty-two cases of primary salivary LECs and 21 cases of secondary salivary LECs were enrolled at the Department of Oral Pathology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University between 2015 and 2017. The expression of Epstein-Barr (EB) virus, PD-L1 and CD8 was examined using chromogenic in situ hybridization (CISH) and immunohistochemistry (IHC) staining. The data were analyzed using SPSS 23.0 software package. Results: EB virus was detected in 61 cases (61/63, 96.8%), including 42 (42/42, 100%) primary LECs and 19 (19/21, 90.5%) secondary LECs. The PD-L1 positive rate (score ≥1) was 97.6% (41/42), and its high-expression rate (score ≥20) was 78.6% (33/42) in primary LECs. The PD-L1 positive rate (score ≥1) was 71.4% (15/21), and its high-expression rate (≥20) was 38.1% (8/21) in secondary LECs. However, the PD-L1 positive rate (score ≥1, P=0.004) and high-expression rate (score ≥20, P=0.001) in primary LECs were higher than those in secondary LECs. There was no difference in the infiltration degree of CD8⁺T lymphocytes between primary and secondary LECs. There was a significant correlation between the expression of PD-L1 and CD8 in primary LECs (P=0.001) and in secondary LECs (P=0.048), respectively. Conclusions: There is PD-L1 expression in primary and secondary salivary LECs, while the expression rate is higher in primary LECs than secondary LECs. The combination of PD-L1 expression and CD8⁺T lymphocytes' presence suggest that most LEC patients might be responsive to immunotherapy, and primary LECs might be more significantly responsive than secondary LECs.