Sevelamer reverses liver fibrosis by deactivation of hepatic stellate cells

Liver fibrosis is a chronic liver disease characterized by a progressive wound healing response caused by chronic liver injury. Currently, there are no approved clinical treatments for liver fibrosis. Sevelamer is used clinically to treat hyperphosphatemia and has shown potential therapeutic effects on liver diseases. However, there have been few studies evaluating the therapeutic effects of sevelamer on liver fibrosis, and the specific mechanisms are still unclear. In this study, we investigated the antifibrotic effects of sevelamer-induced low inorganic phosphate (Pi) stress in vitro and in vivo and analyzed the detailed mechanisms. We found that low Pi stress could inhibit the proliferation of activated hepatic stellate cells (HSCs) by promoting apoptosis, effectively suppressing the migration and epithelial-mesenchymal transition (EMT) of hepatic stellate cells. Additionally, low Pi stress significantly increased the antioxidant stress response. It is worth noting that low Pi stress indirectly inhibited the activation and migration of HSCs by suppressing transforming growth factor β (TGF-β) expression in macrophages. In a rat model of liver fibrosis, oral administration of sevelamer significantly decreased blood phosphorus levels, improved liver function, reduced liver inflammation, and increased the antioxidant stress response in the liver. Our study revealed that the key mechanism by which sevelamer inhibited liver fibrosis involved binding to gastrointestinal phosphate, resulting in a decrease in blood phosphorus levels, the downregulation of TGF-β expression in macrophages, and the inhibition of HSC migration and fibrosis-related protein expression. Therefore, our results suggest that sevelamer-induced low Pi stress can attenuate hepatic stellate cell activation and inhibit the progression of liver fibrosis, making it a potential option for the treatment of liver fibrosis and other refractory chronic liver diseases.

Th2-skewed peripheral T helper cells drives B cells in allergic bronchopulmonary aspergillosis

INTRODUCTION

Patients with allergic bronchopulmonary aspergillosis (ABPA) suffer from repeated exacerbations. However, the involvement of T cell subsets remains unclear.

METHODS

We enrolled ABPA patients, asthma patients and healthy controls. Th1, Th2, Th17, Treg and IL-21+CD4+T cells in total or sorted subsets of peripheral blood mononuclear cells (PBMCs) and ABPA Bronchoalveolar Lavage fluid (BALF) were analyzed by flow cytometry. RNA sequencing of subsets of CD4+T cells were done in exacerbated ABPA patients and healthy controls. Antibodies of T-B cell co-cultures in vitro were measured.

RESULTS

ABPA patients had increased Th2 cells, similar Treg cells and decreased circulating Th1 and Th17 cells. IL-5+IL-13+IL-21+CD4+T cells was rarely detected in healthy controls but significantly elevated in the blood of ABPA patients, especially the exacerbated ones. We found that IL-5+IL-13+IL-21+CD4+T cells were mainly peripheral T helper (Tph) cells (PD-1+CXCR5-), which also presented in the BALF of ABPA patients. The proportions of circulating Tph were similar among ABPA patients, asthma patients and healthy controls, while IL-5+IL-13+IL-21+ Tph cells significantly increased in ABPA patients. Transcriptome data showed that Tph cells of ABPA patients were Th2-skewed and exhibited signatures of follicular T helper (Tfh) cells. When co-cultured in vitro, Tph cells of ABPA patients induced the differentiation of autologous B cells into plasmablasts and significantly enhanced the production of IgE.

CONCLUSION

We identified a distinctly elevated population of circulating Th2-skewed Tph cells that induced the production of IgE in ABPA patients. It may be a biomarker and therapeutic target for ABPA.

Prediction model of no-response before the first transarterial chemoembolization for hepatocellular carcinoma: TACF score

Previous clinic models for patients with hepatocellular carcinoma (HCC) receiving transarterial chemoembolization (TACE) mainly focused on the overall survival, whereas a simple-to-use tool for predicting the response to the first TACE and the management of risk classification before TACE are lacking. Our aim was to develop a scoring system calculated manually for these patients. A total of 437 patients with hepatocellular carcinoma (HCC) who underwent TACE treatment were carefully selected for analysis. They were then randomly divided into two groups: a training group comprising 350 patients and a validation group comprising 77 patients. Furthermore, 45 HCC patients who had recently undergone TACE treatment been included in the study to validate the model's efficacy and applicability. The factors selected for the predictive model were comprehensively based on the results of the LASSO, univariate and multivariate logistic regression analyses. The discrimination, calibration ability and clinic utility of models were evaluated in both the training and validation groups. A prediction model incorporated 3 objective imaging characteristics and 2 indicators of liver function. The model showed good discrimination, with AUROCs of 0.735, 0.706 and 0.884 and in the training group and validation groups, and good calibration. The model classified the patients into three groups based on the calculated score, including low risk, median risk and high-risk groups, with rates of no response to TACE of 26.3%, 40.2% and 76.8%, respectively. We derived and validated a model for predicting the response of patients with HCC before receiving the first TACE that had adequate performance and utility. This model may be a useful and layered management tool for patients with HCC undergoing TACE.

[The efficacy and safety analysis of cervical and abdominal double single-port minimally invasive esophagectomy]

Objective: To summarize the efficacy and safety of minimally invasive esophagectomy through cervical and abdominal double single-port. Methods: A total of 28 patients who underwent cervical and abdominal double single-port minimally invasive radical resection of esophageal cancer from January 2021 to October 2022 in the First Affiliated Hospital of Fujian Medical University were retrospectively collected, including 18 males and 10 females, aged 58-80 (72±4) years. All patients were placed in the supine position, the single port was operated through the cervical mediastinum first, then the single port was operated through the abdominal cavity, and finally the neck was anastomosed. The operative time, intraoperative blood loss, postoperative ambulation time, postoperative drainage tube removal time, postoperative complications, postoperative pathological examination results, postoperative discharge time of patients were recorded and followed. Results: In the included 28 patients, there were twenty-six patients successfully completed the cervical and abdominal double single-port minimally invasive radical resection of esophageal cancer, and two patients were transferred to the right thoracoscopic surgery due to oozing of blood and unclear visual field, without conversion to laparotomy or enlargement of the incision occurred. The operation time was 125 to 215 (152±32) minutes, including 43 to 100 (56±15) minutes in the mediastinum and 35 to 63 (40±5) minutes in the abdominal cavity. Intra-operative blood loss was 55-100 (45±20) ml. There were 8 to 14 (11±3) lymph nodes dissected in the mediastinum and 7 to 15 (9±3) lymph nodes dissected in the abdominal cavity. Twenty-eight patients were active in bed 1 to 2 days after surgery. The left cervical drainage tube was removed 2 days after surgery. There was no anastomotic fistula, anastomotic stenosis, pulmonary infection, chylothorax and stomach emptying disorder in the whole group. Pleural effusion occurred in 4 cases, all of them had pleural damage during the operation, and were cured after postoperative puncture and drainage; two cases had hoarseness and one case had cough after eating, all patients were discharged from hospital after eating liquid. Postoperative hospital median stay was [ M(Q₁, Q₃)] 7(6, 9) d. The postoperative pathological examination results of all patients were squamous cell carcinoma, and the postoperative pathological stage was pT1-3N0-1M0. The median postoperative follow-up was 25 (5, 35) months, and no patients had complications, recurrence, metastasis or death during the follow-up period. Conclusion: The cervical and abdominal double single-hole minimally invasive radical resection of esophageal cancer is safe and feasible, with good short-term efficacy, which provide an opportunity for radical surgery for patients with advanced age, poor cardiopulmonary function or insufficient thoracic conditions.

KLF14/miR-1283/TFAP2C axis inhibits HER2-positive breast cancer progression via declining tumor cell proliferation

MiR-1283 has been identified as a tumor suppressor in some malignancies. Whereas, the role of miR-1283 in HER2-positive (HER2+) breast cancer, particularly its role in regulating cell proliferation, one of the most significant features of tumor progression, is unclear. The related microRNA screened by the breast cancer sample GSE131599 dataset were detected in HER2+ breast cancer tissues and cell lines. Then, the obtained miR-1283 was overexpressed in SKBR3 and BT-474 cells followed by relevant functional assays concerning cell proliferation and apoptosis. The xenograft mouse model was induced and the effect of miR-1283 on tumor growth and cell proliferation was examined. The target of miR-1283 and the transcription factor regulating miR-1283 were predicted and identified. Finally, the influence of transcription factor KLF14 on cell proliferation and apoptosis was investigated. An integrated analysis confirmed that miR-1283 expression was significantly decreased in HER2+ breast cancer tissues. Also, by q-RT-PCR detection, miR-1283 expression was markedly reduced in HER2+ breast cancer tissues and cell lines. The miR-1283 overexpression prevented the proliferation and enhanced apoptosis of HER2+ breast cancer cells, as well as inhibited tumor growth. Mechanistically, miR-1283 inhibited TFAP2C expression by targeting the 3'-untranslated regions of TFAP2C messenger RNA, and the KLF14 enhanced miR-1283 level via binding to its promoter. The result subsequently confirmed the KLF14/miR-1283 signaling suppressed cell proliferation in HER2+ breast cancer. Our results suggested that the KLF14/miR-1283/TFAP2C axis inhibited HER2+ breast cancer progression, which might provide novel insight into mechanical exploration for this disease.

Evaluation of the safety and efficacy of transarterial sevelamer embolization in a rabbit liver cancer model: A challenge on the size rule for vascular occlusion

As the most efficient method to treat hepatocellular carcinoma in the immediate or advanced stage, transarterial chemoembolization (TACE) is coming into the era of microsphere (MP). Drug-eluting beads have shown their huge potential as an embolic agent and drug carrier for chemoembolization, but their sizes are strictly limited to be above 40 μm, which was considered to occlude vessels in a safe mode. microsphere smaller than 40 µm is easy to be washed out and transported to the normal liver lobe or other organs, causing severe adverse events and failed embolization. To determine whether sevelamer ultrafine particle (0.2-0.5 µm) is qualified as a safe and efficient embolic agent, we investigated the safety and therapeutic efficiency of transarterial sevelamer embolization (TASE) in the VX2 rabbit liver cancer model, aiming to challenge the "40 µm" rule on the selection criteria of the MP. In a four-arm study, blank bead (Callisphere, 100-300 µm), luminescent polystyrene microsphere (10, 100 µm), and sevelamer particle were transarterially administered to evaluate the threshold size of the MP size for intrahepatic or extrahepatic permeability. Another four-arm study was designed to clarify the safety and efficiency of preclinical transarterial sevelamer embolizationTASE tests over other techniques. Sham (saline), TASE, C-TACE, and D-TACE (n = 6) were compared in terms of serum chemistry, histopathology, and tumor necrosis ratio. In the first trials, the "40 µm" rule was detectable on the VX2 cancer model, but the regulation has no application to the new embolic agent as sevelamer ultrafine particles have not been found to leak out from the VX2 lesions, only found in the embolized vessels. Pathology proves that less viable tumor residue was found 2 weeks after the procedure, evidencing a better therapeutic outcome. No adverse events were found except for a short stress response. These results indicate that sevelamer is a safe and efficient embolic as an alternative to the current MP-based embolization therapy techniques.

Pi-inducedin-situaggregation of sevelamer nanoparticles for vascular embolization

Decades have witnessed rapid progress of polymeric materials for vascular embolic or chemoembolic applications. Commercially available polymeric embolics range from gelatin foam to synthetic polymers such as poly(vinyl alcohol). Current systems under investigation include tunable, bioresorbable microspheres composed of chitosan or poly(ethylene glycol) derivatives,in situgelling liquid embolics with improved safety profiles, and radiopaque embolics that are trackablein vivo. In this paper, we proposed a concept of 'responsive embolization'. Sevelamer, clinically proved as an inorganic phosphate binder, was ground into nanoparticles. Sevelamer nanoparticle is highly mobile and capable of swelling and aggregating in the presence of endogenous inorganic phosphate, thereby effectively occluding blood flow in the vessel as it was administered as an embolic agent for interventional therapy. Moreover, citrated sevelamer nanoparticles delayed the aggregation, preferable to penetrate deeply into the capillary system. On the rabbit VX2 liver cancer model, both sevelamer particles aggregates occlude the tumor feeding artery, but backflow was found for the pristine one, thereby citrate passivation of sevelamer nanoparticles endows it have potential from 'bench to bedside' as a new type of vascular embolic.

Intratumoral Pi deprivation benefits chemoembolization therapy via increased accumulation of intracellular doxorubicin

It is a decade-long controversy that transarterial chemoembolization (TACE) has definite priority over transarterial embolization (TAE) in treating patients with hepatocellular carcinoma (HCC), since HCC cells are regularly resistant to chemotherapy by enhanced expression of proteins that confer drug resistance, and ABC transporters pump the intracellular drug out of the cell. We addressed this issue by modulating the chemo-environment. In an animal model, sevelamer, a polymeric phosphate binder, was introduced as an embolic agent to induce intratumoral inorganic phosphate (Pi) starvation, and trans-arterially co-delivered with doxorubicin (DOX). The new type of TACE was named as DOX-TASE. This Pi-starved environment enhanced DOX tumoral accumulation and retention, and DOX-TASE thereby induced more severe tumor necrosis than that induced by conventional TACE (C-TACE) and drug-eluting bead TACE (D-TACE) at the same dose. In vitro tests showed that Pi starvation increased the cellular accumulation of DOX in an irreversible manner and enhanced cytotoxicity and cell apoptosis by suppressing the expression of ABC transporters (P-glycoprotein (P-gp), BCRP, and MRP1) and the production of intracellular ATP. Our results are indicative of an alternative interventional therapy combining chemotherapy with embolization more effectively.

Sevelamer arsenite nanoparticle as a Pi-responsive drug carrier and embolic agent for chemoembolization

Arsenic trioxide (As₂O₃, ATO) has limited therapeutic benefit to treat solid tumors, whether used alone or in combination. Nanoscale drug delivery vehicles have great potential to overcome the limitation of the utility of ATO by rapid renal clearance and dose-limiting toxicity. Polymeric materials ranging from gelatin foam to synthetic polymers such as poly(vinyl alcohol) were developed for vascular embolic or chemoembolic applications. Recently, we have introduced sevelamer, an oral phosphate binder, as a new polymeric embolic for vascular interventional therapy. In this paper, sevelamer arsenite nanoparticle with a polygonal shape and a size of 50–300 nm, synthesized by anionic exchange from sevelamer chloride, was developed as a Pi-responsive bifunctional drug carrier and embolic agent for chemoembolization therapy. At the same arsenic dosage, sevelamer arsenite-induced severer tumor necrosis than ATO on the VX2 cancer model. In vitro tests evidenced that Pi deprivation by sevelamer could enhance ATO’s anticancer effect. The results showed that ATO in Pi starvation reduced cell viability, induced more apoptosis, and diminished the mitochondrial membrane potential (Δψm) of cells since Pi starvation helps ATO to further down-regulate Bcl-2 expression, up-regulate Bax expression, enhance the activation of caspase-3 and increase the release of cytochrome c, and the production of excessive reactive oxygen species (ROS). Sevelamer arsenite not only plays a Pi-activated nano-drug delivery system but also integrated anticancer drug with embolic for interventional therapy. Therefore, our results presented a new administration route of ATO as well as an alternative chemoembolization therapy.

Circular RNA circ-ERBB2 promotes HER2-positive breast cancer progression and metastasis via sponging miR-136-5p and miR-198

Background

Circular RNAs (circRNAs) are pivotal regulators of various human cancers and circ-ERBB2 is abnormally expressed in breast cancer cells. However, the role and mechanism of circ-ERBB2 in HER2-positive breast cancer are still unknown.

Methods

The circ-ERBB2 expressions in the tumor tissues of HER2-positive breast cancer patients were tested using quantitative real-time PCR. The circ-ERBB2 function was investigated by cell counting kit 8 assay, Transwell, flow cytometry and Western blot. Mechanistically, fluorescence in situ hybridization, RNA immunoprecipitation, RNA pull-down and dual-luciferase reporter gene assays were conducted to confirm the interaction between circ-ERBB2 and miR-136-5p or miR-198 in HER2-positive breast cancer cells.

Results

Circ-ERBB2 was elevated in the tumor tissues of HER2-positive breast cancer patients. Functionally, the interference with circ-ERBB2 repressed HER2-positive breast cancer cell proliferation, migration, invasion and accelerated cell apoptosis. Furthermore, the mechanistic analysis corroborated that circ-ERBB2 acted as a competing endogenous RNA for miR-136-5p or miR-198 to relieve the repressive influence of miR-136-5p or miR-198 on its target transcription factor activator protein 2C (TFAP2C). Meanwhile, in vivo assays further corroborated the oncogenic function of circ-ERBB2 in HER2-positive breast cancer.

Conclusions

Circ-ERBB2 accelerated HER2-positive breast cancer progression through the circ-ERBB2/miR-136-5p/TFAP2C axis or the circ-ERBB2/miR-198/TFAP2C axis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-03114-8.

Intratumoral inorganic phosphate deprivation: A new anticancer strategy?

Tumor epidemiology, as well as tumor microenvironments and cancer cell signaling study, has been presented with statistical relevance of inorganic phosphate (Pi) to tumorigenesis. Although serum Pi is still not acknowledged as a clinical tumor biomarker, abnormally high Pi concentration in serum or tumor lesions is gradually recognized as a characteristic of malignancy. On the other hand, phosphate binder (e.g. La₂ (CO₃)₃, Fosrenols) has been clinically approved to treat hyperphosphatemia, a metabolic disease characterized by a high serum phosphate level. We hypothesize that, if reducing phosphate burden comes to benefit tumor therapy, could systemic or intratumoral administration of phosphate binder effectively deprive tumor Pi concentration, and then inhibit tumor growth and metastases? From the past clinical and preclinical outcomes, we'd conclude that Pi is not only a metabolite during tumor growth but also a force to trigger tumor progression and metastases. Two types of cancer models were developed to initiate this study. Firstly, a patient-derived xenograft mouse model of colorectal cancer was designed, where mice were administered systemically or intratumorally with lanthanum acetate (a molecular phosphate binder), and the serum or intratumoral Pi concentration levels were found to a dropdown. Secondly, a rabbit VX2 liver tumor was set up for the local-regional therapy model, where lanthanum acetate was intratumorally administered by the standard transcatheter arterial chemoembolization procedure, and it significantly reduced intratumoral Pi concentration. Therefore, Pi deprivation by phosphate binder might be a new anticancer strategy if reducing phosphate burden could effectively arrest tumor growth and delay metastatic progression.

Sustained release of arsenic trioxide benefits interventional therapy on rabbit VX2 liver tumor

The benefit of chemotherapy as a constituent of transcatheter arterial chemoembolization (TACE) is still in debate. Recently we have developed arsenic trioxide nanoparticle prodrug (ATONP) as a new anticancer drug, but its systemic toxicity is a big issue. In this preclinical TACE study, ATONP emulsified in lipiodol behaved as drug-eluting bead manner. Sustained release of arsenic from ATONP within occluded tumor caused very low arsenic level in plasma, avoiding the "rushing out" effect as ATO did. Correspondingly, intratumoral arsenic accumulation and inorganic phosphate deprivation were simultaneously observed, and arsenic concentration was much higher as ATONP was transarterially administered than ATO, or intravenously injected. Tumor necrosis and apoptosis were remarkably more severe in ATONP group than ATO, but no significant hepatic and renal toxicity was perceived. In brief, ATONP alleviated arsenic toxicity and boosted the therapeutic effect of TACE via Pi-activated drug sustainable release.

Diluted hydrochloric acid generates larger radiofrequency ablation lesions in excised porcine livers

PURPOSE

This study evaluated the influence of continuous infusion of diluted hydrochloric acid during radiofrequency ablation (RFA) on the size of ablated lesions.

MATERIALS AND METHODS

Experiments were performed in 20 excised porcine livers using three different treatment modalities: (1) normal saline-enhanced RFA (NS-RFA), which was normal saline pumped into ablated tissue during RFA; (2) diluted hydrochloric acid ablation (DHAA), which was 3 mol/L diluted hydrochloric acid (HCl) injected into hepatic tissue without RFA; and (3) HCl-enhanced RFA (HCl-RFA), which was 3 mol/L diluted HCl continuously infused into ablated tissue during RFA. We produced 20 HCl-RFA and NS-RFA lesions, respectively, using a monopolar perfusion electrode connected to a commercially available radiofrequency generator, and 20 DHAA lesions using an 18-gauge Chiba needle. The ablated lesions were evaluated both macroscopically and histologically. Dimensions of lesions were compared among HCl-RFA, NS-RFA, and DHAA.

RESULTS

The ablated lesions had an elliptical-like shape and were well-demarcated with normal liver tissue. The mean volume, longitudinal diameter, and transverse diameter of NS-RFA lesions were 11.24±0.29 cm(3), 3.4±0.07 cm, and 2.48±0.03 cm, those of HCl-RFA lesions were 58.14±3.05 cm(3), 5.51±0.05 cm, and 4.49±0.11 cm, and those of DHAA lesions were 4.41±0.16 cm(3), 2.43±0.08 cm, and 1.8±0.03 cm, respectively. The mean dimensions of HCl-RFA lesions were the largest among the three types of ablation (P < 0.001).

CONCLUSION

Under the present experimental conditions, the continuous infusion of diluted HCl during RFA can generate larger ablated lesions than NS-RFA or DHAA in excised porcine livers.

Transarterial embolization ablation of hepatocellular carcinoma with a lipiodol-ethanol mixture

AIM: To determine the safety and effectiveness of transarterial embolization ablation (TEA) of hepatocellular carcinoma (HCC) with a lipiodol-ethanol mixture.

METHODS: Between January 1 and December 31, 2009, 15 patients with HCC (13 men/two women, aged 38-75 years) accepted TEA treatment and were enrolled in this study, including five newly diagnosed patients and 10 with refractory disease. Two months after TEA, angiography and contrast computed tomography (CT) were performed, and responses were assessed using a modified version of Response Evaluation Criteria in Solid Tumors (RECIST version 1.1). The follow-up period was to June 30, 2010.

RESULTS: Every new case was treated once. Angiography was performed immediately after TEA, and showed that the tumor-feeding vessels were completely embolized and that lipiodol was densely deposited inside tumors. Two months after treatment, contrast CT showed no enhanced lesions. Alpha fetoprotein levels returned to normal in four patients and markedly decreased in another. mean ± SD survival after treatment was 10.8 ± 4.5 mo. All five patients survived during the follow-up period. Ten patients with refractory disease were treated a total of 14 times. Angiography immediately after TEA showed that blood flow to the tumors was obviously decreased in all cases, and contrast CT showed obvious depositions of lipiodol. Two months after treatment, the tumors had shrunk (6/10) or were stable (3/10). One had progressed after 2 mo and died of tumor rupture 3 mo after TEA. mean ± SD survival after treatment was 8.6 ± 4.3 mo; two patients survived during the follow-up period. Adverse effects included reversible hepatic decompensation, upper abdominal pain, and fever.

CONCLUSION: TEA is an effective therapy for patients with HCC and might be more effective than transcather arterial chemoembolization for treating refractory disease.

[Experimental radiofrequency ablation in porcine liver ex vivo with "wet" unipolar electrode]

OBJECTIVE

To observe the effects of radiofrequency ablation in porcine liver ex vivo with "wet" RITA UniBlate unipolar electrode, evaluate the morphologic characteristic of the ablated zones and explore the impact upon the ablation lesions of time, temperature and set power of "wet" monopolar electrodes.

METHODS

The maximal effective ablation electrode length of this "wet" unipolar electrode is 2.5 cm. According to ablation time, temperature and power respectively, the experiment was divided into three major groups of A, B, C (11 sub-groups). The investigators observed the morphological characteristics of ablation lesions, measured the longitudinal and transverse distance of ablation beyond the electrode tip and calculated the volume of ablation lesion. Statistical analysis was performed with one-way ANOVA upon the above-mentioned four parameters. And the pathological examinations were made with HE staining.

RESULTS

(1) All of ablated zones were ellipsoid. The cross-section of ablation lesions appeared to have 3 zones from the inside out: central zone, coagulated zone, hemorrhage and edema zone. (2) When ablating time and temperature increased to 15 min and 103 degrees C respectively, the ablated zones peaked: longitudinal diameter, transverse diameter, ablation distance beyond electrode tip and volume of each ablated zone was (3.49 +/- 0.09) cm, (2.40 +/- 0.13) cm, (0.79 +/- 0.09) cm and (10.6 +/- 1.3) cm(3) respectively. With power as a variable, different sizes between ablated zones showed no statistical significance. (3) The morphology of ablated zones became irregular when the electrodes were located around larger blood vessels.

CONCLUSION

The ablating time and temperature are the major factors of affecting the size of radiofrequency ablation lesion with RITA "wet" unipolar electrode.

Computed tomography and magnetic resonance imaging findings of solitary fibrous tumors in the pelvis: correlation with histopathological findings

OBJECTIVE

We aimed to analyze the computed tomography (CT) and magnetic resonance imaging (MRI) findings of pelvic solitary fibrous tumors (SFTs) and to improve the diagnostic efficacy for such tumors.

METHODS

Six cases of pelvic SFTs confirmed by histopathology were analyzed retrospectively. Of the 6 patients, 4 had undergone CT scanning, and 2 had undergone magnetic resonance imaging. All the patients had undergone unenhanced and contrast-enhanced examinations, and 2 had also undergone dynamic CT enhancement examination. Image characteristics such as shape, size, number, edge, attenuation or intensity for each lesion before and after contrast enhancement were analyzed and compared with the pathomorphology of the tumors.

RESULTS

All the 6 cases showed oval or rounded and well-defined masses. Unenhanced CT images showed heterogeneous masses with patchy, necrotic foci in 3 cases and homogeneous mass in 1 case. None of the tumors showed calcification. Contrast-enhanced CT images showed marked, heterogeneous enhancement in the first and second cases. Dynamic enhancement scan demonstrated mild homogeneous enhancement in the third case and mild prolonged, delayed enhancement and washout in the fourth case. T1-weighted MR images showed heterogeneous mild hypointense lesion with linear hyperintensity in 1 case, and homogeneous isointensity in the other. T2-weighted images showed heterogeneous mixed intensity in 1 case and mostly hyperintensive lesion with hypointense foci in another case. A case showed marked heterogeneous enhancement and another showed marked homogeneous enhancement on contrast-enhanced T1-weighted images.

CONCLUSION

Radiological findings of pelvic SFTs are variable and nonspecific. However, a well-defined, ovoid or rounded mass with hypointense on MR T2-weighted images and variable enhancement on CT and MR images may suggest the diagnosis of SFTs. Pelvic SFTs should be included in the differential diagnosis of regional tumors.

[Experimental study of CT-guided percutaneous ethanol ablation in rabbit renal VX2 tumor]

BACKGROUND AND OBJECTIVE

CT-guided percutaneous ethanol ablation (PEA) has been widely used in treating solid tumors such as hepatoma, lung cancer, adrenal nonfunctional adenoma. This study was to explore the efficacy, safety and feasibility of CT-guided PEA in treating renal tumor in rabbit.

METHODS

Twenty-five rabbits carrying VX2 tumor were randomized into PEA group (15 rabbits) and control group (10 rabbits). After CT-guided PEA, the area of the largest cross section lipiodol deposition in PEA group was measured. After one week, the kidneys carrying VX2 tumor were removed, tumor size in both groups and the area of the largest cross section coagulation necrosis in PEA group were measured. Wound infection and the changes of living habits of the rabbits were observed after experiment.

RESULTS

A total of 25 VX2 tumors were developed in the 25 rabbits. The area of the largest cross section was 1.38-2.25 cm(2), with an average of (1.61+/-0.04) cm(2). There was no significant difference in tumor size between the two groups. After ablation, the area of lipiodol deposition in PEA group was 1.31-1.85 cm(2), with an average of (1.56+/-0.05) cm(2). At one week after ablation, the area of the largest cross section of tumors was significant smaller in PEA group than in control group [(1.58+/-0.03) cm(2) vs. (1.94+/-0.03) cm(2), P<0.05]; the area of coagulation necrosis in PEA group was 1.27-1.78 cm(2), with an average of (1.54 +/-0.04) cm(2), and was similar to the area of lipiodol deposition (P>0.05). Tumor tissue in ablation areas showed acidophilia changes and irregular coagulation necrosis. There was no obvious complication in PEA group.

CONCLUSION

CT-guided PEA can effectively inactivate rabbit kidney VX2 tumors, and it is a safe and feasible treatment without obvious complications.

Chiral synthesis and enzymatic resolution of (S)-(-)piperazine-2-carboxylic acid using enzyme alcalase

Enantiomerically pure (S)-piperazine-2-carboxylic acid was synthesized by kinetic resolution of methyl-4-(tert-butyroxycarbonyl)-piperazine-2-carboxylate using a low cost enzyme alcalase.

Pressure and flux profiles in bead-filled ultrafiltration/microfiltration hollow fiber membrane modules

A general mathematical model for the prediction of pressure, flow rate, and flux profiles in an ultrafiltration/microfiltration hollow fiber membrane module whose shell side is filled with beads has been developed. The model was studied for a variety of operational modes in such modules, e.g., ultrafiltration/microfiltration, permeate flow rate control, Starling flow (encountered in hollow fiber bioreactors), and tube-side elution (encountered in filtration-cum-chromatography processes), etc., with or without a bead-filled extended section at the permeate outlet. An algorithm is provided to determine the model parameters from experimental data using the model equations. The solutions developed have been used to study the uniformity of transmembrane pressure profile along the module length using a quantity called the uniformity factor alpha. This factor shows that the model can be a useful tool for achieving the desired module performance in a number of quite different applications. The model predicts successfully the nature of the transmembrane pressure profile and the solvent flux profile in situations that are quite different, namely, conventional ultrafiltration and Starling flow. The approach used in this study can also be adopted to develop a model for description of other operational modes such as backflushing and shell-side elution used in the processes of filtration-cum-chromatography. Those applications employing similar device configurations may also use this model to predict the pressure and flux profiles to facilitate the design of the process and the operation conditions.

An integrated process for biomolecule isolation and purification

Biomolecule isolation and purification from a fermentation broth usually involve centrifugation, filtration, adsorption, and chromatography steps. Each step contributes to the product cost and product loss. In this research, a cyclic process integrating commercially available ultrafiltration membranes and chromatographic resin beads was developed to achieve the same goal in one device. The device consisted of ion exchange beads on the shell side of a hollow fiber ultrafiltration module. Loading of proteins on the stationary phase on the shell side was carried out for a period of 5-20 min from the permeate on the shell side produced from tube-side feed in ultrafiltration. The eluent was then introduced either from the shell-side inlet or tube-side inlet; the chromatographic fractions were collected from the shell-side outlet. The column was regenerated/washed next to start a new cycle. Systems studied in this cyclic process include the following binary mixtures: myoglobin and beta-lactoglobulin; hemoglobin and bovine serum albumin; and myoglobin and alpha-lactalbumin. Excellent resolutions of the proteins were obtained. A yeast-based cellular suspension containing a mixture of myoglobin and alpha-lactalbumin was also applied to this device. The target proteins were recovered and purified successfully. The cyclic process-based device integrates clarification, concentration, and chromatographic purification of biomolecules and is suitable for both extracellular and intracellular products.

Chromatographic removal of endotoxin from hemoglobin preparations. Effects of solution conditions on endotoxin removal efficiency and protein recovery

In this work, affinity chromatography was used to remove endotoxin from human hemoglobin preparations with a Sterogene Acticlean Etox column. The effects of solution conditions on endotoxin removal efficiency and protein recovery have been investigated. It has been found that cations Na(+) or Ca(2+) reduced endotoxin removal efficiency from 73% (sample prepared with endotoxin-free water) to 31% (sample prepared with 0.15 M NaCl, ionic strength, I = 0.15 M), and from 73% sample prepared with endotoxin-free water) to 9% (sample prepared with 0.05 M CaCl2, ionic strength, I = 0.15 M). It has also been found that the protein recovery was increased from 90% to 99%, respectively.