Baseline gut microbiome and metabolites are correlated with alcohol consumption in a zonisamide clinical trial of heavy drinking alcoholic civilians

Development and severity of alcohol use disorder (AUD) has been linked to variations in gut microbiota and their associated metabolites in both animal and human studies. However, the involvement of the gut microbiome in alcohol consumption of individuals with AUD undergoing treatment remains unclear. To address this, stool samples (n=48) were collected at screening (baseline) and trial completion from a single site of a multi-site double-blind, placebo-controlled trial of Zonisamide in individuals with AUD. Alcohol consumption, gamma-glutamyl transferase (GGT), and phosphatidylethanol (PEth)levels were measured both at baseline and endpoint of 16-week trial period. Fecal microbiome was analyzed via 16S rRNA sequencing and metabolome via untargeted LC-MS. Both sex (p = 0.003) and psychotropic medication usage (p = 0.025) are associated with baseline microbiome composition. The relative abundance of 12 genera at baseline was correlated with percent drinking reduction, baseline and endpoint alcohol consumption, and changes in GGT and PeTH over the course of treatment (p.adj < 0.05). Overall microbiome community structure at baseline differed between high and low responders (67-100% and 0-33% drinking reduction, respectively; p = 0.03). A positive relationship between baseline fecal GABA levels and percent drinking reduction (R=0.43, p < 0.05) was identified by microbiome function prediction and confirmed by ELISA and metabolomics. Predicted microbiome function and metabolomics analysis have found that tryptophan metabolic pathways are over-represented in low responders. These findings highlight importance of baseline microbiome and metabolites in alcohol consumption in AUD patients undergoing zonisamide treatment.

Injectable hydrogels derived from marine polysaccharides as cell carriers for large corneal epithelial defects

Injectable hydrogels have been employed for sutureless repair of corneal epithelial defects, which can perfectly fit the defect sites and minimize the associated discomfort. However, numerous hydrogels are ineffective in treating large corneal epithelial defects and still suffer from poor biocompatibility or weak applicability when used as cell carriers. Herein, hydroxypropyl chitin/carboxymethyl chitosan (HPCT/CMCS) temperature-sensitive hydrogels are fabricated, and their physicochemical properties and suitability for corneal epithelial repair are investigated. The results demonstrate that HPCT/CMCS hydrogels have excellent temperature sensitivity between 20 and 25 °C and a transparency of over 80 %. Besides, HPCT/CMCS hydrogels can promote cell proliferation and facilitate cell migration of primary rabbit corneal epithelial cells (CEpCs). A rabbit large corneal epithelial defect model (6 mm) is established, and CEpCs are transplanted into defect sites by HPCT/CMCS hydrogels. The results suggest that HPCT/CMCS/CEpCs significantly enhance the repair of large corneal epithelial defects with a healing rate of 99.6 % on day 8, while reducing inflammatory responses and scarring formation. Furthermore, HPCT/CMCS/CEpCs can contribute to the reconstruction of damaged tissues and the recovery of functional capacities. Overall, HPCT/CMCS hydrogels may be a feasible corneal cell carrier material and can provide an alternative approach to large corneal epithelial defects.

Recent Review on Selected Xenobiotics and Their Impacts on Gut Microbiome and Metabolome

As it is well known, the gut is one of the primary sites in any host for xenobiotics, and the many microbial metabolites responsible for the interactions between the gut microbiome and the host. However, there is a growing concern about the negative impacts on human health induced by toxic xenobiotics. Metabolomics, broadly including lipidomics, is an emerging approach to studying thousands of metabolites in parallel. In this review, we summarized recent advancements in mass spectrometry (MS) technologies in metabolomics. In addition, we reviewed recent applications of MS-based metabolomics for the investigation of toxic effects of xenobiotics on microbial and host metabolism. It was demonstrated that metabolomics, gut microbiome profiling, and their combination have a high potential to identify metabolic and microbial markers of xenobiotic exposure and determine its mechanism. Further, there is increasing evidence supporting that reprogramming the gut microbiome could be a promising approach to the intervention of xenobiotic toxicity.

A Novel Porous Butyryl Chitin-Animal Derived Hydroxyapatite Composite Scaffold for Cranial Bone Defect Repair

Bone defects, a common orthopedic problem in clinical practice, are a serious threat to human health. As alternative materials to autologous bone grafts, synthetic cell-free functionalized scaffolds have been the focus of recent research in designing scaffolds for bone tissue engineering. Butyryl chitin (BC) is a derivative of chitin (CT) with improved solubility. It has good biocompatibility, but few studies have investigated its use in bone repair. In this study, BC was successfully synthesized with a degree of substitution of 2.1. BC films were prepared using the cast film method and showed strong tensile strength (47.8 ± 4.54 N) and hydrophobicity (86.4 ± 2.46°), which was favorable for mineral deposition. An in vitro cytological assay confirmed the excellent cell attachment and cytocompatibility of the BC film; meanwhile, in vivo degradation indicated the good biocompatibility of BC. Hydroxyapatite (HA), extracted from bovine cancellous bone, had good cytocompatibility and osteogenic induction activity for the mouse osteoblast cell line MC3T3-E1. With the aim of combining the advantages of BC and HA, a BC-HA composite scaffold, with a good pore structure and mechanical strength, was prepared by physical mixing. Administered into skull defects of rats, the scaffolds showed perfect bone-binding performance and effective structural support, and significantly promoted the regeneration of new bone. These results prove that the BC-HA porous scaffold is a successful bone tissue engineering scaffold and has strong potential to be further developed as a substitute for bone transplantation.

Video-assisted superior mediastinal lymphadenectomy for papillary thyroid cancer: a case report

Superior mediastinal lymph node metastases in papillary thyroid cancer are uncommon. The clinical characteristics and surgical strategy of superior mediastinal lymph node metastases remain unclear. Superior mediastinal lymphadenectomy can be accomplished either by a transcervical or transsternal approach. Transsternal approach for superior mediastinal lymphadenectomy can cause great damage; transcervical approach sometimes results in inadequate exposure. Here we report our experience of a papillary thyroid cancer patient with superior mediastinal lymph node metastases who underwent video-assisted superior mediastinal lymphadenectomy. A 49-year-old woman diagnosed with papillary thyroid cancer in left thyroid underwent unilateral lobectomy and ipsilateral central and lateral node dissection in the local hospital 4 years ago. Currently lymph node metastases were found in mediastinum and the right neck, some of which were adjacent to the right innominate vein. Unilateral lobectomy, ipsilateral central and lateral node dissection, and video-assisted superior mediastinal lymphadenectomy were successfully performed by transcervical approach. Subsequently, the patient received thyroxine suppression therapy and adjuvant radioiodine treatment. Video-assisted superior mediastinal lymphadenectomy, providing adequate exposure for a complete superior mediastinal lymphadenectomy, is proved to be safe and feasible.

Multifunctional effects of wound dressing based on chitosan-coordinated argentum with resistant bacterial penetration

Third-degree scald, causing serious tissue destruction with continuous pain, easily leads to microbial infections and delayed wound healing. Therefore, a multifunctional treatment is attractive for seriously damaged tissue. Herein, carboxymethyl chitosan-coordinated argentum (Ag-CMC) was synthesized via a complexation method, and then the Ag⁺ release, antibacterial activity, biocompatibility, pain relief and wound healing properties of Ag-CMC were investigated in vitro and in vivo. The results revealed that Ag⁺ had interacted with carboxymethyl chitosan, containing approximately 1.2% of silver. The Ag-CMC (50-200 μg/mL) with Ag⁺ sustained release exhibited significant antibacterial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, drug-resistant E. coli, PA, MRSA and good biocompatibility with L929 cells. Furthermore, antibacterial and wound healing experiments demonstrated that Ag-CMC achieved an effective contraction rate of 90% after 28 days by accelerating re-epithelialization, regulating inflammation response, relieving pain and infections. Therefore, Ag-CMC is a safe multifunctional treatment for wound healing and infections.

Functional thermosensitive hydrogels based on chitin as RIN-m5F cell carrier for the treatment of diabetes

Herein, the thermosensitive hydroxypropyl chitin (HPCT) hydrogel was prepared and the chemical structures, microstructures, rheological properties and degradation in vitro were investigated. The HPCT hydrogel possessed satisfactory biocompatibility in mouse fibroblast cells and Sprague Dawley rats. On the other hand, N-acetylglucosamine (NAG) and carboxymethyl chitosan (CMCS) provided favorable capacity for promoting cell proliferation, delaying cell apoptosis, and facilitating the insulin secretion of rat pancreatic beta cells (RIN-m5F) in three-dimensional culture. Most importantly, the effects of HPCT/NAG and HPCT/CMCS thermosensitive hydrogels as RIN-m5F cells carriers were evaluated via injection into different areas of diabetic rats. Our results demonstrated that HPCT/NAG and HPCT/CMCS hydrogels loaded RIN-m5F cells could keep cells survival, maintain insulin secretion and reduce blood glucose for one week. Overall, the functional thermosensitive hydrogels based on HPCT were effective cell carriers for RIN-m5F cells and might provide novel strategy for the treatment of diabetes via cell engineering.

Novel dopamine-modified oxidized sodium alginate hydrogels promote angiogenesis and accelerate healing of chronic diabetic wounds

Herein, the dopamine (DA) was grafted with oxidized sodium alginate (OSA) via Schiff base reduction reaction, aiming to fabricate novel DA-grafted OSA (OSA-DA) hydrogels with enhanced biocompatibility and suitable adhesion for clinical applications. The chemical structures of OSA-DA were characterized via UV-Vis, FTIR and ¹H NMR spectroscopy analysis. The hydrogel characteristics, biocompatibility, as well as the chronic diabetic wound healing efficacy were investigated. Our results demonstrated that DA was grafted with OSA successfully with highest grafting rate of 7.50%. Besides, OSA-DA hydrogels possessed suitable swelling ratio and appropriate adhesion characteristics. Additionally, OSA-DA exhibited satisfactory cytocompatibility and cell affinity in L-929 cells, and superior biocompatibility in SD rats. Moreover, OSA-DA exerted remarkable promoting effects on migration and tube formation of human umbilical vein endothelial cells (HUVECs). Studies on full-thickness excision chronic diabetic wounds further revealed that OSA-DA hydrogels could accelerate healing via promoting angiogenesis, reducing inflammation response, and stimulating collagen deposition. Overall, our studies would provide basis for SA-based hydrogels as clinical wound dressings.

Hemostatic performance of chitosan-based hydrogel and its study on biodistribution and biodegradability in rats

Hemostasis is of great significance regardless of the smooth operation or postoperative recovery. Therefore, it is urgent to develop a hemostatic material with excellent biodegradability and biocompatibility. It is well known that both carboxymethyl chitosan and hyaluronic acid with biodegradability and biocompatibility have wound healing promoting property. Here, a degradable chitosan-based hydrogel was prepared based on carboxymethyl chitosan and cross-linked by oxidized hyaluronic acid. The hemostatic performance of the hydrogel in rat liver resection injury was evaluated which results showed that the hydrogel exhibited comparable hemostatic properties compared with Fibrin Sealant. In addition, the hydrogel proved to be rapidly absorbed by the body without significant accumulation in vivo, demonstrating good biodegradability and biocompatibility. The overall results suggested the hydrogel will be a promising hemostatic hydrogel for controlling bleeding.

Effect of chitosan oligosaccharide-conjugated selenium on improving immune function and blocking gastric cancer growth

Selenium (Se) is a potential chemopreventive or chemotherapeutic agent against malignant tumor. Selenium-oligosaccharides are important selenium source of dietary supplementation. Due to the insufficient natural production, it is therefore urgent to develop selenium-oligosaccharides by artificial synthesis. Chitosan, the N-deacetylated derivative of chitin, has been applied widely in biomedical field, owing to its nontoxicity, hydrophilicity, biocompatibility, and biodegradation. While chitosan is water insoluble at neutral pH, limiting its application in physiological conditions. Chitosan oligosaccharide (COS), the hydrolysate of chitosan, is readily soluble in water because of the shorter chain lengths of the oligomers and the free amino groups in the D-glucosamine units. This study was aimed at preparing COS-conjugated selenium (COS-Se) and examining the toxicity and ability on improving immune function and blocking gastric cancer growth. Our results demonstrated that COS-Se displayed directly co-mitogenic and mitogenic actions on mouse splenocytes proliferation in vitro. Besides, COS-Se treatment could effectively elevate phagocytosis and increase the secretion of anti-inflammatory cytokine in mouse peritoneal macrophages. Further in vivo experiments showed that COS-Se exhibited immuno-enhancing effects through promoting the phagocytic index, spleen index and thymus index with no obvious toxicity to Kunming mice. Moreover, COS-Se inhibited proliferation and metastasis of human gastric cancer cells, with non-toxic effects on the normal fibroblast cells in vitro. COS-Se supplementation could significantly repress the growth of gastric adenocarcinoma through reducing levels of CD34, vascular endothelial growth factor and matrix metalloproteinase-9 of nude mice. In conclusion, COS-Se was non-toxic and showed great potential as a functional food ingredient in cancer prevention.

Efficacy and safety of endothelin receptor antagonists in type 2 diabetic kidney disease: A systematic review and meta-analysis of randomized controlled trials

AIM

To analyse the efficacy and safety of endothelin receptor antagonists for people with diabetic kidney disease.

METHODS

Randomized controlled trials comparing endothelin receptor antagonists with placebo in people with diabetic kidney disease were identified through PubMed, Embase and the Cochrane Library. We used a random-effect model to calculate the mean difference or risk ratio with the 95% CI.

RESULTS

Seven studies with a total of 4730 participants were included. Overall, endothelin receptor antagonists significantly reduced albuminuria compared with placebo (standardized mean difference -0.48, 95% CI -0.64 to -0.33). Atrasentan, in particular, effectively reduced albuminuria (standardized mean difference -0.58, 95% CI -1.00 to -0.17) and the risk of composite renal endpoints (risk ratio 0.65; 95% CI 0.49 to 0.88), with insignificant change in the rate of congestive heart failure (risk ratio 1.40, 95% CI 0.76 to 2.56) and mortality (risk ratio 1.11, 95% CI 0.77 to 1.61). In contrast, although avosentan reduced albuminuria (standardized mean difference -0.47, 95% CI -0.57 to -0.36) and the risk of composite renal endpoints (risk ratio 0.63, 95% CI 0.42 to 0.94), it was associated with a significant increase in congestive heart failure risk (risk ratio 2.61, 95% CI 1.36 to 5.00) and an insignificant increase in mortality risk (risk ratio 1.50, 95% CI 0.81, 2.78). No significant change in efficacy or safety outcomes with bosentan was detected. Dose-response analysis indicated that 0.75 mg/day atrasentan is expected to be optimal for renoprotection, with maximal albuminuria reduction and minimal fluid retention events.

CONCLUSIONS

Among the endothelin receptor antagonists, atrasentan and avosentan, but not bosentan, are effective for renoprotection in people with diabetic kidney disease. Compared with other types and doses, atrasentan 0.75 mg/day is the most promising, with maximal albuminuria reduction and minimal fluid retention. Vigilant monitoring of congestive heart failure risk is needed in future clinical practice. (PROSPERO registration no. CRD42020169840).

A self-healing and injectable hydrogel based on water-soluble chitosan and hyaluronic acid for vitreous substitute

Vitreous, an essential dioptric medium for the human eyes, must be filled with artificial materials once damaged. Carboxymethyl chitosan (CMCTS) is one of the most important water-soluble chitosan derivatives with improved biocompatibility and biodegradability. In this study, oxidized hyaluronic acid (OHA) was prepared as crosslinking reagent. CMCTS and OHA were used to develop a biocompatible, self-repairing and in-situ injectable hydrogel for vitreous substitutes. Results showed the hydrogel with controllable swelling properties, high transparency, acceptable cytocompatibility on mouse fibroblast L929 and histocompatibility in vivo. Furthermore, hydrogel was injected in-situ into the vitreous cavity after vitrectomy on New Zealand Rabbits, no significant and persistent adverse effects were observed during the 90-day follow-up period. In addition, the hydrogel maintained intraocular pressure of the operated eyes and the inherent position of the retina. Collectively, this injectable, biodegradable, nontoxic hydrogel possessed enormous potential to become a vitreous substitute material.

Low-dose CT of paediatric paranasal sinus using an ultra-low tube voltage (70 kVp) combined with the flash technique

AIM

To evaluate the radiation dose and diagnostic image quality of low-dose computed tomography (CT) of the paranasal sinus in children, with acquisition at an ultra-low tube voltage (70 kVp) combined with the Flash technique.

MATERIALS AND METHODS

Eighty paediatric patients underwent CT of the paranasal sinus and were divided into two groups according to different protocols (group A: 80 kVp protocol with conventional spiral mode [n=40] and group B: 70 kVp protocol with Flash scan mode [n=40]). For each examination, the CT dose index (CTDIvol), dose-length product (DLP), and effective dose (ED) were estimated. The image noise, signal-to-noise ratio (SNR), and overall subjective diagnostic image quality were also evaluated.

RESULTS

For radiation dose, the CTDIvol (mGy), DLP (mGy·cm), and ED (mSv) values of the 70 kVp protocol were significantly lower than those of the 80 kVp protocol (CTDIvol: 1.57±0.009 versus 0.39±0.004 mGy, p<0.001; DLP: 19.88±2.01 versus 6.31±0.52 mGy·cm, p<0.001; ED: 0.079±0.016 versus 0.024±0.005 mSv, p<0.001). Compared with those of the 80-kVp protocol, the image noise increased by 40.7% (p=0.113), the SNR_soft-tissue decreased by 48.9%, and the SNR_bone increased by 10.1% with the 70-kVp protocol (p=0.176 and 0.227, respectively). There was no significant difference in the overall subjective image quality grades between these two groups (p=0.15).

CONCLUSION

When imaging the paranasal sinus in children, an ultra-low tube voltage (70 kVp) combined with the Flash CT technique can reduce the radiation dose significantly while maintaining diagnostic image quality with clinically acceptable image noise.

Studies on anti-hepatocarcinoma effect, pharmacokinetics and tissue distribution of carboxymethyl chitosan based norcantharidin conjugates

Aiming to enhance therapeutic efficiency and reduce toxic effect of norcantharidin (NCTD), NCTD-conjugated carboxymethyl chitosan (CMCS) conjugates (CNC) were prepared and evaluated for the treatment of hepatocellular carcinoma. In vitro cellular assays revealed that CNC conjugates possessed potent inhibitory effects on the proliferation and migration of BEL-7402 cells. Besides, CNC could change nuclear morphology of tumor cells. In comparison with free NCTD at equivalent dose, CNC exerted enhanced therapeutic efficiency and diminished systemic toxicity in H22 tumor-bearing mice with a tumor inhibition rate of 56.20%. Further investigation about pharmacokinetics and tissue distribution by high performance liquid chromatography (HPLC) analysis indicated that CNC showed a longer retention time in blood circulation and reduced distribution in heart and kidney tissues, thereby exerting different antitumor efficacy and toxicity compared with free NCTD. Our results suggested that CNC conjugates based on CMCS as polymer carriers might be used as a potential clinical alternative for NCTD in tumor therapy.

Clinical outcomes of ultrasound-guided radiofrequency ablation for the treatment of primary papillary thyroid microcarcinoma

AIM

To evaluate the safety, efficacy, and long-term outcomes of ultrasound-guided radiofrequency ablation (RFA) for the treatment of primary papillary thyroid microcarcinoma (PTMC).

MATERIALS AND METHODS

A total of 37 patients with 38 PTMC nodules underwent RFA at a power of 20 W between September 2014 and December 2017. The clinical data of these patients were reviewed retrospectively and analysed. Imaging studies of the nodules were conducted, and the patients' thyroid function was assessed before RFA; 1, 3, 6, and 12 months after RFA; and every 6 months thereafter. The volumes and volume reduction rate (VRR) of the nodules were also calculated.

RESULTS

RFA with a low power of 20 W was used in the treatment of 37 patients with 38 PTMC nodules. All nodules achieved complete ablation, no complications occurred, and thyroid function was not affected. During follow-up, the volume of the nodules gradually decreased. Twelve months after ablation, the mean volumes of the nodules significantly decreased to 0.01±0.03 ml with a VRR of 99.34±3.49%. At a median follow-up of 6 (range: 1-18) months, 37 of the 38 nodules were completely absorbed, and no recurrence was observed in all 37 patients.

CONCLUSIONS

Low-power RFA showed good safety and promising efficacy outcomes for the treatment of PTMC. In addition to surgery and active surveillance, RFA may be an alternative treatment option for patients with PTMC.

Antitumor evaluation of carboxymethyl chitosan based norcantharidin conjugates against gastric cancer as novel polymer therapeutics

Novel polymer-drug conjugates (CNC) were prepared from carboxymethyl chitosan (CMCS) and norcantharidin (NCTD) via amidation reaction and characterized by FTIR and ¹H NMR spectroscopy. The aim of this study was to elucidate the antitumor efficacy of CNC on gastric cancer and the possible underlying mechanisms. The CNC conjugates possessed significant inhibitory effects on the proliferation of SGC-7901 cells and suppressed the migration as well as tube formation of HUVECs. Besides, Hoechst 33258 staining and Annexin V-FITC/PI detection suggested that the conjugates were more effective in triggering apoptosis of SGC-7901 cells compared with free NCTD. Moreover, CNC remarkably reduced systemic toxicity and enhanced the antitumor efficacy in vivo with a tumor suppression rate of 59.57% against SGC-7901 gastric tumor in BALB/c nude mice. Further investigation about the underlying mechanisms indicated that CNC could upregulate expressions of TNF-α and Bax, and downregulate expressions of VEGF, Bcl-2, MMP-2 and MMP-9, thereby inhibiting tumor metastasis and inducing apoptosis in vivo. Overall, our results demonstrated that CNC might be a promising and feasible polymer therapeutics for gastrointestinal tumor therapy.

Cortistatin inhibits arterial calcification in rats via GSK3β/β-catenin and protein kinase C signalling but not c-Jun N-terminal kinase signalling

AIM

Cortistatin (CST) is a newly discovered endogenous active peptide that exerts protective effects on the cardiovascular system. However, the relationship between CST and aortic calcification and the underlying mechanism remain obscure. Therefore, we investigated effects of CST on aortic calcification and its signalling pathways.

METHODS

Calcium content and alkaline phosphatase (ALP) activity were measured using the o-cresolphthalein colorimetric method and ALP assay kit respectively. Protein expression of smooth muscle (SM)-ɑ-actin, osteocalcin (OCN), β-catenin, glycogen synthase kinase 3β (GSK3β), p-GSK3β, protein kinase C (PKC), p-PKC, c-Jun N-terminal kinase (JNK) and p-JNK was determined using Western blotting.

RESULTS

In aorta from a rat vitamin D3 calcification model, CST abrogated calcium deposition and pathological damage, decreased the protein expression of OCN and β-catenin and increased SM-ɑ-actin expression. In a rat cultured vascular smooth muscular cell (VSMC) calcification model induced by β-glycerophosphate (β-GP), CST inhibited the increase in ALP activity, calcium content and OCN protein and the decrease in SM-α-actin expression. CST also inhibited the β-GP-induced increase in p-GSK3β and β-catenin protein (both P < .05). The inhibitory effects of CST on ALP activity, calcium deposition and β-catenin protein were abolished by pretreatment with lithium chloride, a GSK3β inhibitor. CST promoted the protein expression of p-PKC by 68.5% (P < .01), but not p-JNK. The ability of CST to attenuate β-GP-induced increase in ALP activity, calcium content and OCN expression in the VSMC model was abolished by pretreatment with the PKC inhibitor Go6976.

CONCLUSION

These results indicate that CST inhibits aortic calcification and osteogenic differentiation of VSMCs likely via the GSK3β/β-catenin and PKC signalling pathways, but not JNK signalling pathway.

Eye on the B-ALL: B-cell receptor repertoires reveal persistence of numerous B-lymphoblastic leukemia subclones from diagnosis to relapse

The strongest predictor of relapse in B-cell acute lymphoblastic leukemia (B-ALL) is the level of persistence of tumor cells after initial therapy. The high mutation rate of the B-cell receptor (BCR) locus allows high-resolution tracking of the architecture, evolution and clonal dynamics of B-ALL. Using longitudinal BCR repertoire sequencing, we find that the BCR undergoes an unexpectedly high level of clonal diversification in B-ALL cells through both somatic hypermutation and secondary rearrangements, which can be used for tracking the subclonal composition of the disease and detect minimal residual disease with unprecedented sensitivity. We go on to investigate clonal dynamics of B-ALL using BCR phylogenetic analyses of paired diagnosis-relapse samples and find that large numbers of small leukemic subclones present at diagnosis re-emerge at relapse alongside a dominant clone. Our findings suggest that in all informative relapsed patients, the survival of large numbers of clonogenic cells beyond initial chemotherapy is a surrogate for inherent partial chemoresistance or inadequate therapy, providing an increased opportunity for subsequent emergence of fully resistant clones. These results frame early cytoreduction as an important determinant of long-term outcome.

GPU accelerated FDTD solver and its application in MRI

The finite difference time domain (FDTD) method is a popular technique for computational electromagnetics (CEM). The large computational power often required, however, has been a limiting factor for its applications. In this paper, we will present a graphics processing unit (GPU)-based parallel FDTD solver and its successful application to the investigation of a novel B1 shimming scheme for high-field magnetic resonance imaging (MRI). The optimized shimming scheme exhibits considerably improved transmit B(1) profiles. The GPU implementation dramatically shortened the runtime of FDTD simulation of electromagnetic field compared with its CPU counterpart. The acceleration in runtime has made such investigation possible, and will pave the way for other studies of large-scale computational electromagnetic problems in modern MRI which were previously impractical.

Comparative genomic and protein signatures and intratumoral treatment responses in patients with metastatic breast cancer (MBC) treated with paclitaxel (PTX) and 2-methoxyestradiol (2ME2)

e22049

Background: Tumors respond to both chemotherapy and radiation through a number of poorly understood survival mechanisms. These potential mechanisms include upregulation of anti-apoptotic and pro-angiogenic pathways, including those regulated by HIF-1α. Sequential MBC biopsies were used to examine 1) the effects of PTX on intratumoral HIF-1α mediated pathways; and 2) the ability of a HIF-1α inhibitor (2ME2) to modulate the tumor's HIF- 1α response to PTX. Methods: Key eligibility included pts with MBC, ECOG 0–2, unlimited prior therapies, and biopsiable tumors. Pts were treated on a 28-day schedule with weekly PTX (90 mg/m2 D1, D8, D15) and daily oral 2ME2 (1000, 1250,1500 or 2000 mg qid starting D8) and had 3 tumor biopsies: baseline (A); D8 post-PTX/pre-2ME2 (B); D22 post-PTX/post- 2ME2 (C). Serial biopsies were compared for genomic and single protein changes. Results: 20 pts (median age 52 yrs [31- 75]) were treated. 60% had ≥2 prior regimens for MBC, 35% had ≥3. No unexpected grade 3/4 toxicities were seen: neutropenia (n=6), anemia (2), hypophosphatemia (2), PE (1). The clinical benefit rate was 25% (4 PR, 1 SD). There were 13 pairs of tumor biopsies to compare points A/B and 10 to compare B/C. There were no consistent gene expression changes between A and B. Significant differences at C vs. B included changes in hypoxia-responsive genes (including CA9, HIF-2α) and upregulation of pro- angiogenic factors and hemoglobin transcripts. For the B/C comparison, 2 distinct groups emerged: the first (biopsy site liver) showed downregulation of gene expression programs driven by ER and the second (lymph node, breast) showed upregulation of endothelial cell- related genes. Conclusions: Combination therapy with PTX and 2ME2 is a well-tolerated and viable option for delaying disease progression for patients with heavily pretreated MBC. Significant gene expression changes before and after exposure to 2ME2 may reflect changes in tumor microcirculation consistent with the idea of vascular normalization. The potential significance of the differences in gene expression observed in the 2 distinct groups remains to be investigated. Supported by Komen Grant BCTR0504044 (MWD).

[Table: see text]

The effects of paclitaxel (PTX) and 2-methoxyestradiol (2-ME2) on tumor oxygenation and HIF-1α in breast cancer

3517

Background: Radiation activates HIF-1a via a free radical mediated mechanism associated with reoxygenation. This response could be inhibited, resulting in reduced tumor vascularity and proliferation. Preclinical breast cancer models and a Phase Ib clinical trial (CT) were employed to look at the effects of chemo with or without an oral HIF-1a inhibitor, 2-ME2 (EntreMed) on tumor oxygenation and HIF-1a. Methods: Preclinical models of chemo effects on HIF-1a/oxygenation used 4T1 tumors and either doxorubicin (DOX) or cyclophosphamide (CTX). In addition, MDA-MB-231 tumors were treated with 2-ME2 (5days), and HIF-1a/MVD was assessed. In the CT, up to 15 pts with metastatic breast cancer, and biopsiable (>2 cm) non-bone sites were eligible. Tx was: D 1: PTX, 90 mg/m2; D 8: PTX, 90 mg/m2 with 2-ME2 (cohorts of 1,000/1,250/1,500 mg, qid). PTX was given 3 out of 4 wks. Bxs were done at enrollment, D8 (post-PTX), and D22 (post-PTX/2-ME2). Tumors were examined for changes in HIF-1a and CA9 levels, MVD, and genomic signatures of hypoxia. Plasma was obtained for osteoponin, PAI-1, and VEGF. Results: DOX and CTX both led to increases in HIF-1a, oxygenation, vascularity, and proliferation 4–10 days post treatment in the 4T1 model, while 2-ME2 reduced HIF-1a and MVD post treatment (5 d) in the MDA-MB-231 model. The CT opened in 6–2006, 9 pts have consented and 8 pts have undergone sequential biopsies and accrual continues. No DLT have been seen. Biopsy sites include chest wall, liver, and LN. Sufficient tissue/RNA/plasma has been obtained and the planned analyses will be presented. Conclusions: HIF-1a and tumor oxygenation appear to be modulated as a response to chemotherapy. The combination of PTX and 2-ME2 is clinically active, well-tolerated, and could serve as one of the first approaches to target HIF-1a in order to optimize therapy. Supported by Komen Grant BCTR0504044.

[Table: see text]

Characterization of nelfinavir binding to plasma proteins and the lack of drug displacement interactions

OBJECTIVES

To determine the characteristics of the binding of nelfinavir and active M8 to alpha1-acid glycoprotein (AAG) and human serum albumin (HSA), and to examine the displacement effects of drugs binding extensively to AAG (ritonavir and saquinavir) or to HSA (salicylic acid and valproic acid).

METHODS

Free drugs were separated by equilibrium dialysis after incubation with human plasma or purified plasma proteins and after co-incubation with potential displacers. Association constants were estimated from double-reciprocal plots of the data.

RESULTS

Nelfinavir and M8 free fractions [fractions of unbound drug (fus)] were 0.42+/-0.08% (mean+/-standard deviation) and 0.64+/-0.07%, respectively. For the two analytes, respectively, association constants were 7.25 x 10(7)/m and 3.33 x 10(7)/m for AAG and 1.11 x 10(6)/m and 7.92 x 10(5)/m for HSA. Nelfinavir fu in an AAG solution was significantly (P < 0.01) increased by the addition of ritonavir or saquinavir, whereas it was unaltered by addition of these drugs to whole plasma. Similarly, fu in an HSA solution was significantly increased (P < 0.01) by the addition of salicylic acid or valproic acid, whereas there was no difference in the free fraction in plasma.

CONCLUSIONS

The affinity of nelfinavir for human plasma proteins was higher than that of M8, and both nelfinavir and M8 showed higher affinity to AAG than to HSA. The free fraction of nelfinavir was not affected by drugs that bind extensively to AAG or albumin when these drugs were added to whole plasma in combination, suggesting a compensatory effect of alternate binding proteins.

New insights into the karyotypic relationships of Chinese muntjac (Muntiacus reevesi), forest musk deer (Moschus berezovskii) and gayal (Bos frontalis)

To investigate the karyotypic relationships between Chinese muntjac (Muntiacus reevesi), forest musk deer (Moschus berezovskii) and gayal (Bos frontalis), a complete set of Chinese muntjac chromosome-specific painting probes has been assigned to G-banded chromosomes of these three species. Sixteen autosomal probes (i.e. 6-10, 12-22) of the Chinese muntjac each delineated one pair of conserved segments in the forest musk deer and gayal, respectively. The remaining six autosomal probes (1-5, and 11) each delineated two to five pairs of conserved segments. In total, the 22 autosomal painting probes of Chinese muntjac delineated 33 and 34 conserved chromosomal segments in the genomes of forest musk deer and gayal, respectively. The combined analysis of comparative chromosome painting and G-band comparison reveals that most interspecific homologous segments show a high degree of conservation in G-banding patterns. Eleven chromosome fissions and five chromosome fusions differentiate the karyotypes of Chinese muntjac and forest musk deer; twelve chromosome fissions and six fusions are required to convert the Chinese muntjac karyotype to that of gayal; one chromosome fission and one fusion separate the forest musk deer and gayal. The musk deer has retained a highly conserved karyotype that closely resembles the proposed ancestral pecoran karyotype but shares none of the rearrangements characteristic for the Cervidae and Bovidae. Our results substantiate that chromosomes 1-5 and 11 of Chinese muntjac originated through exclusive centromere-to-telomere fusions of ancestral acrocentric chromosomes.

Effect of Anti-Cancer Drugs on the Binding of 125I-Fibrinogen to Two Leukaemia Cell Lines In Vitro

Anti-cancer drugs may be able to inhibit tumour growth and metastasis by blocking fibrinogen- and/or fibrin-related pathways. To test this hypothesis, the effect of various anti-neoplastic drugs on the binding of 125I-Fibrinogen to two leukaemia cell lines, HL60 and P388, was investigated. All the drugs tested inhibited the binding of fibrinogen to leukaemia cells. This effect was particularly marked for drugs that act as inhibitors of protein synthesis. Since these anti-neoplastic drugs do not have anti-coagulant actions, these results provide evidence for the potential of targeting tumour fibrinogen as a new form of cancer chemotherapy.

A direct determination of thymidine triphosphate concentrations without dephosphorylation in peripheral blood mononuclear cells by LC/MS/MS

A rapid, sensitive and specific analytical method with minimal sample preparation for the measurement of thymidine triphosphate (TTP) in peripheral blood mononuclear cells (PBMC) by LC/MS/MS has been developed. PBMC were separated from whole blood or buffy coat. The analyte and internal standard were extracted from PBMC with 70% methanol (pH 7.2). These extracts after centrifugation were directly injected onto LC/MS/MS without need for any further sample preparation. The calibration curve was linear over the range 0.8-800 ng/ml. Mean inter- and intra-assay coefficients of variation (CVs) over the range of the standard curve were less than 10%. The overall recovery of TTP was 103.5%.

Age changes in orthodontic treatment need: a longitudinal study of 10- and 13-year-old children, using the Dental Aesthetic Index

The Dental Aesthetic Index (DAI) was used to assess the prevalence of unmet orthodontic treatment need in 150 13-year-old schoolchildren in Dunedin, New Zealand, and to compare the findings with those obtained in the same children at 10 years of age. Fewer 13-year-olds (27%) had a "mandatory" need of orthodontic treatment than when they were 10 years old (33%), 20% had "no/little" need for orthodontic treatment, 33% had an "elective" need for treatment and 20% had a "desirable" need for treatment. The fall in DAI scores is attributed to over-sensitivity of the Index to mixed dentition traits. When the individual scores were analysed, only 7% of the 10-year-olds were given the same scores as when they were 13 years old, 52% were given higher scores and 41% were given lower scores. This disagreement between scores was masked to a limited extent by the DAI categories: 49% of the 10-year-olds were assigned to the same DAI category at 13 years of age, 20% to a greater treatment-need category and approximately 30% to a lower treatment-need category. The DAI, in common with other malocclusion indices, is unreliable over time because it is affected by developmental changes in the occlusal traits measured.

Incidence of presbycusis of Korean populations in Seoul, Kyunggi and Kangwon provinces

Presbycusis, a bilateral sensorineural hearing loss caused by changes in the inner ear, is related to multiple factors such as noise exposure and otologic disease. In institute-based studies, we tried to determine the incidence of presbycusis in Korean populations living in Seoul, Kyunggi and Kangwon provinces by gender and age groups. The subjects were people who had visited health promotion centers. Pure tone audiometry was done over 20 years on 6,028 subjects. In a community-based study, the subjects were elderly residents of Kanghwa-do area. There were no obvious factors that could cause hearing impairment in the subjects. For the pure tone audiometry, hearing threshold was obtained by using the six-dimension method. The incidence of presbycusis for subjects aged 65 years and older was 37.8% and 8.3% for > or = 27 dB HL criterion and > or = 41 dB HL criterion, respectively. The incidence increased with age. A statistically significant difference in the hearing threshold was found between men and women aged 65 years or older. No differences were found between the community-based study and the institute- based studies. There was a high incidence (about 40%) of presbycusis among Koreans aged 65 years or older (for > or = 27 dB HL criterion). With an aging population, we anticipate that this report could be used to provide a basic data for the study of presbycusis.

A longitudinal study of orthodontic treatment need in Dunedin schoolchildren

The Index of Orthodontic Treatment Need (IOTN) was used to assess unmet orthodontic treatment need in 152 13-year-old Dunedin schoolchildren, and to compare the findings with those obtained in the same children 3 years previously. The children were randomly selected from Dunedin schools as 10-year-olds, and had not received orthodontic treatment. Approximately 86 percent of the 13-year-old children had "No-little" need for orthodontic treatment when assessed by the child-assessed Aesthetic Component (AC) and the examiner-assessed AC. Slightly less than half the children had "No-little" need for orthodontic treatment when assessed with the Dental Health Component (DHC). More 10- and 13-year-old children "Needed" orthodontic treatment with the DHC than with the AC. Both the examiner-assessed AC and the DHC assessed significantly fewer 13-year-olds as needing orthodontic treatment than the same children as 10-year-olds. Complete agreement between the grades assigned at 10 and 13 years occurred in 30-43 percent of the children and, in the treatment-need categories, between 53 percent (DHC) and 84 percent (child-assessed AC) of the children. The fall in treatment need over the 3-year period may be due to selection bias, over-sensitivity of the IOTN to mixed dentition traits, or both. Although a number of 10-year-old children were assigned different grades as 13-year-olds, many remained within the same treatment category. The apparent stability of the IOTN to assess treatment need in 10- and 13-year-old children is attributed to the grouping of different occlusal traits in the same treatment-need category, and to the small number of treatment-need categories in each component.

Induction of gastritis and gastric ulcer in Mongolian gerbils infected with Helicobacter pylori

OBJECTIVE

To induce the model of Mongolian gerbil infected by Helicobacter pylori (HP) and to observe the changes of the infiltration and the proliferation of inflammatory cells before and after the bactericidal treatment.

METHODS

The animal model of HP infection was induced by inoculating the HP strain (American Type Culture Collection) to male Mongolian gerbil MGS/Sea (SPF). Half a month, 1 month and 3 months after inoculation, kill the animals and make HE staining and immunohistochemistry staining of the stomach to observe the pathological changes.

RESULTS

The infiltration of a great number of inflammatory cells was observed with the center of the mucosa of pylorus at the second week of HP infection. At the 3rd month of infection, ulcer appeared near the lesser curvature side of the pylorus. On the early stage of infection, the lesion was acute inflammation characterized by the neutrophilic infiltration, and then transformed into the chronic inflammation characterized by the lymphatic infiltration and the wide formation of lymphatic follicles.

CONCLUSION

Mongolian gerbil is an ideal and standard animal model of HP infection.

Neuroendocrine evidence for dopaminergic actions of hypericum extract (LI 160) in healthy volunteers

BACKGROUND

We studied the effect of a single dose of a formulation of a methanolic extract of Hypericum perforatum (HP), also known as St. John's wort, on plasma concentrations of growth hormone (GH), prolactin (PRL), and cortisol (CORT) in 12 healthy male volunteers.

METHODS

Subjects received 9 tablets of the finished product Jarsin 300 and placebo in a double-blind, balanced-order, cross-over design.

RESULTS

Following HP relative to placebo, there was a significant increase in plasma GH and a significant decrease in plasma PRL. Plasma CORT levels were unchanged.

CONCLUSIONS

Taken together with data from animal experimental studies, the findings suggest that this dose of HP may increase some aspects of brain dopamine function in humans.

Globular domains of agrin are functional units that collaborate to induce acetylcholine receptor clustering

Agrin, an extracellular matrix protein involved in neuromuscular junction formation, directs clustering of postsynaptic molecules, including acetylcholine receptors (AChRs). This activity resides entirely in the C-terminal portion of the protein, which consists of three laminin-like globular domains (G-domains: G1, G2 and G3) and four EGF-like repeats. Additionally, alternate mRNA splicing yields G-domain variants G2(0,4) with 0- or 4-amino-acid inserts, and G3(0, 8,11,19) with 0-, 8-, 11- or 19-amino-acid inserts. In order to better understand the contributions of individual domains and alternate splicing to agrin activity, single G-domains and covalently linked pairs of G-domains were expressed as soluble proteins and their AChR clustering activity measured on cultured C2 myotubes. These analyses reveal the following: (1) While only G3(8) exhibits detectable activity by itself, all G-domains studied (G1, G2(0), G2(4), G3(0) and G3(8)) enhance G3(8) activity when physically linked to G3(8). This effect is most pronounced when G2(4) is linked to G3(8) and is independent of the order of the G-domains. (2) The deletion of EGF-like repeats enhances activity. (3) Increasing the physical separation between linked G1 and G3(8) domains produces a significant increase in activity; similar alterations to linked G2 and G3(8) domains are without effect. (4) Clusters induced by two concatenated G3(8) domains are significantly smaller than all other agrin forms studied. These data suggest that agrin G-domains are the functional units which interact independently of their specific organization to yield AChR clustering. G-domain synergism resulting in biological output could be due to physical interactions between G-domains or, alternatively, independent interactions of G-domains with cell surface receptors which require spatially localized coactivation for optimal signal transduction.

Elongated stylohyoid process: a report of three cases

The stylohyoid process is part of the stylohyoid chain--the styloid process, the stylohyoid ligament, and the lesser cornu of the hyoid bone. The stylohyoid chain is derived from the second branchial arch. Mineralisation of the stylohyoid ligament and ossification at the tip may increase the length of the styloid process. An elongated stylohyoid or styloid process is considered to be the source of craniofacial and cervical pain commonly known as Eagle's syndrome. In some instances the stylohyoid process may be considerably elongated, yet remain asymptomatic. This paper reports three patients with elongated stylohyoid processes discovered incidentally on routine radiographic examination.

[A flavonoid compound in Ginkgo biloba L. leaves]

One compound was isolated for the first time from ethyl acetate extract of Ginkgo biloba leaves and identified as kaempferol-3-O-rhamnoside by spectroscopic methods.