Enhancing the Anti-tumor Potency of a Novel Siglec-15 Antibody by Engineering its Fc-mediated Effector Functions

Siglec-15, an inhibitory immune checkpoint, is an emerging target in cancer immunotherapy. Blocking the function of Siglec-15 is an excellent strategy for cancer treatment and antibody blockade has been used to target Siglec-15. However, whether Fc-mediated effector functions contribute to the therapeutic effect of antibodies remains unclear. Herein, we generated a monoclonal antibody, 1-15D1, which had a high binding affinity with Siglec-15 and strongly activated T-cell immune response in vitro. Subsequently, the Fc-mediated effector functions of 1-15D1 were explored in a Siglec-15 humanized mouse model, and further improvement in antitumor efficacy was observed in the mouse IgG2a isotype group. Thus, we demonstrate that the antitumor effects of 1-15D1 were mediated via multiple factors. In addition to the T-cell immune response, 2 novel mechanisms were explored, including the internalization of the cell surface Siglec-15 and Fc-mediated effector functions. In conclusion, our studies not only provide a potential agent for the improvement of cancer immunotherapy but also suggest that a specific role of Fc-mediated immune regulation may improve the therapeutic potency of Siglec-15 monoclonal antibody.

Efficacy and Safety of Probiotics in Geriatric Patients with Constipation: Systematic Review and Meta-Analysis

BACKGROUND

Probiotics may be an effective alternative to traditional drug therapy for constipation in the elderly.

OBJECTIVE

To assess the efficacy and safety of probiotics in managing constipation among the elderly.

METHODS

Eight databases were queried for randomized controlled trials (RCTs) investigating probiotics' efficacy in addressing constipation among the elderly until January 2023. The meta-analysis was conducted employing R software version 4.2.2. The Cochrane risk of bias tool was utilized to evaluate the risk of bias, and the GRADE approach was employed to assess the credibility of the evidence concerning the efficacy of probiotics in treating constipation in older individuals.

RESULTS

A total of six RCTs involving 444 patients were included. Two studies were rated as low risk of bias. The meta-analysis findings revealed that probiotics, when compared to a placebo, led to an increase in stool frequency (MD = 1.02,95% CI [0.21, 2.07], p<0.05, very low quality), the probiotic group exhibited a notable impact on ameliorating symptoms associated with constipation (OR = 11.28, 95%CI [7.21, 17.64], p < 0.05, very low quality), no significant disparities were observed in terms of efforts to evacuate, manual maneuvers, and the incidence of adverse events (p>0.05).

CONCLUSION

The available evidence indicates a degree of uncertainty, ranging from low-to-very low, suggesting the efficacy of probiotics in augmenting bowel frequency and ameliorating constipation-related symptoms among elderly patients with constipation. Nevertheless, given the quality of the studies included, it is advisable to conduct further well-designed investigations with substantial sample sizes to substantiate the findings of this study.

Selection of Payloads for Antibody-Drug Conjugates Targeting Ubiquitously Expressed Tumor-Associated Antigens: a Case Study

The main objective of this work was to demonstrate which kind of payload is the suitable choice for antibody-drug conjugates directed to widely expressed tumor-associated antigen. Trop-2 is overexpressed in various solid tumors, but it is also present on the epithelium of several normal tissues. A well-designed anti-Trop-2 ADC demands a good balance of efficacy and toxicity. In this research, MMAE, SN-38, and DXd were selected as candidates for payloads of the anti-Trop-2 mAb SY02. The antitumor activities and safety profiles of these ADCs were investigated to compare the therapeutic windows. Robust in vitro cytotoxicity was observed on human pancreatic cancer cell CFPAC-1 and breast cancer cell MDA-MB-468 with IC₅₀ generally in the subnanomolar range. Consistent with in vitro assay, SY02-DXd and SY02-SN-38 demonstrated superior efficacy in CFPAC-1 xenograft models with TGI rates of 98.2% and 87.3%, respectively. However, SY02-MMAE could hardly inhibit the tumor growth. Subsequently, antitumor activities of these ADCs were further compared in MDA-MB-468 xenograft model. Complete tumor regression was observed in SY02-DXd and SY02-MMAE groups, indicating their potent antitumor activities. In an exploratory safety and pharmacokinetic study, SY02-DXd demonstrated the best safety profile with minimal adverse events in cynomolgus monkeys, while SY02-MMAE exhibited severe on-target skin toxicity which caused death. In conclusion, SY02-DXd demonstrated superior efficacy and safety with the widest therapeutic window. Based on the efficacy and safety results, moderate cytotoxic payloads would be ideal choices for ADCs targeting ubiquitously expressed antigens.

An Innovative Site-Specific Anti-HER2 Antibody-Drug Conjugate with High Homogeneity and Improved Therapeutic Index

Purpose

Antibody-drug conjugates (ADCs) have emerged as a potent cancer therapeutic option in recent years. DP303c is a HER2-targeting ADC with a cleavable linker-MMAE payload. The current study aimed to evaluate the therapeutic potentials of DP303c in vitro as well as in vivo.

Materials and Methods

Size exclusion chromatography (SEC), reverse-phase high-performance liquid chromatography (RP-HPLC), and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to analyze the physicochemical characterization of DP303c. An enzyme-linked immunosorbent assay (ELISA), a cell-based assay, and bio-layer interferometry (BLI) were used to evaluate DP303c’s affinity with HER2 and Fc receptors. A confocal laser scanning microscopy was used to observe the internalization of DP303c. Antibody-dependent cell-mediated cytotoxicity (ADCC) and cytotoxicity assays were used to investigate the activity of DP303c in vitro. The antitumor activity of DP303c was assessed in vivo in the HER2-positive cell-derived xenograft model.

Results

DP303c was a site-specific anti-HER2 antibody-drug conjugate with a monomethyl auristatin E (MMAE) with an average drug-to-antibody ratio (DAR) of 2.0. DP303c showed a high affinity with HER2 and could be effectively internalized. In vitro and in vivo, DP303c showed stronger antitumor activity as compared to trastuzumab-DM1 (T-DM1) in a series of HER2-positive cancer cells and cell-derived xenograft (CDX) models, especially in the lower HER2-expressing cells. DP303c also exhibited high serum stability and a good PK profile.

Conclusion

DP303c was a steady and homogenous DAR 2 ADC that was predicted to deliver MMAE inhibitor to tumor cells. DP303c demonstrated remarkable anticancer efficacy against T-DM1 in xenograft models. DP303c was a strong candidate for the treatment of patients with HER2-positive cancer.

Comparison of the prognostic value of stress and rest pulmonary transit time estimation using myocardial perfusion CMR

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Clinical Research Training Fellowship

Background

Pulmonary transit time (PTT) is a quantitative biomarker of cardiopulmonary status. Rest PTT was previously shown to predict outcomes in specific disease models, but clinical adoption is hindered but challenges in data acquisition. Whether evaluation of PTT during stress encodes incremental prognostic information has not been previously investigated as scale.

Objectives

To compare the prognostic value of stress and rest PTT derived from a fully automated, in-line method of estimation using perfusion CMR, in a large patient cohort.

Methods

A retrospective two-center study of patients referred clinically for adenosine stress myocardial perfusion assessment using CMR. Analysis of right and left ventricular cavity arterial input function curves from first pass perfusion was performed automatically, allowing the in-line estimation of both rest and stress PTT. Association with major adverse cardiovascular events (MACE) was evaluated. MACE was defined as a composite outcome of myocardial infarction, stroke, heart failure admission and ventricular tachycardia or appropriate ICD treatment (including ICD shock and/or anti-tachycardia pacing).

Results

985 patients (67% male, median age 62 years (IQR 52,71)) were included, with median left ventricular ejection fraction (LVEF) of 62% (IQR 54-69). Median stress PTT was shorter than rest PTT 6.2 (IQR 5.1, 7.7) seconds versus 7.7 (IQR, 6.4, 9.2) seconds. Stress and rest PTT were highly correlated (r = 0.69; p &lt; 0.001). Stress PTT also correlated with LVEF (r=-0.37), stress MBF (r=-0.31), LVEDVi (r = 0.24), LA area index (r = 0.32) (p &lt; 0.001 for all). Over a median follow-up period of 28.6 (IQR, 22.6 35,7) months, MACE occurred in 61 (6.2%) patients. After adjusting for prognostic factors, both rest and stress PTT, independently predicted MACE, but not all-cause mortality. For every 1xSD (2.39s) increase in rest PTT the adjusted hazard ratio (HR) for MACE was 1.43 (95% CI 1.10-1.85, p = 0.007). The hazard ratio for one standard deviation (2.64s) increase in stress PTT was 1.34 (95% CI 1.048-1.723; p = 0.020) after adjusting for age, LVEF, hypertension, diabetes, sex and presence of LGE

Conclusions

In this 2-center study of 985 patients, we deploy a fully automated method of PTT estimation using perfusion mapping with CMR and show that both stress and rest PTT are independently associated with adverse cardiovascular outcomes. In this patient cohort, there is no clear incremental prognostic value of stress PTT, over its evaluation during rest.

Figure 1. Stress and Rest Pulmonary Transit Time estimation using myocardial perfusion CMR

Figure 2. Event-free survival curves for major adverse cardiovascular events (Heart failure hospitalization, myocardial infarction, stroke and ventricular tachycardia/ICD treatment) according to mean rest PTT (8.05seconds) and mean stress PTT (6.7seconds). Log-rank for both p &lt; 0.05

[Site-specific monoPEGylated interferon alpha2a mediated by microbial transglutaminase]

PEGylation is considered one of the most successful techniques to improve the characteristics of protein drugs including to increase the circulating half-life of proteins in blood and to decrease their immunogenicity and antigenicity. One known PEG modification method is to attach PEG to the free amino group, typically at lysine residues or at the N-terminal amino acid with no selectivity, resulting in a heterogeneous product mixture. This lack of selectivity can present problems when a therapeutic PEGylated protein is being developed, because predictability of activity and manufacturing reproducibility are needed for regulatory approval. Enzymatic PEGylation of proteins is one route to overcome this limitation. Transglutaminases (TGase) are enzyme candidates for site-specific PEGylation. We use human interferon alpha 2a (IFN α2a) as a test case, and predict that the potential modification residues are Gln101 by computational approach as it contains 12 potential PEGylation sites. IFN α2a was PEGylated by Y shaped PEG40k-NH2 mediated by microbial transglutaminase. Our results show that the microbial transglutaminase mediated PEGylation of IFN α2a was site-specific only at the site of Gln101 in IFN α2a, yielding the single mono-conjugate PEG-Gln101-IFN α2a with a mass of 59 374.66 Da. Circular dichroism studies showed that PEG-Gln101-IFN α2a preserved the same secondary structures as native IFN α2a. As expected, the bioactivity and pharmacokinetic profile in rats of PEG-Gln101-IFN α2a revealed a significant improvement to unmodified IFN α2a, and better than PEGASYS.

[Expression, purification and characterization of N-glycosylation mutant human IFN-λ1 in Pichia pastoris]

IFN-λ1 is a member of a new family of interferons called type Ⅲ IFNs with similar functions to type ⅠIFNs. Previously we obtained recombinant soluble human rhIFN-λ1 from Pichia pastoris. However, the hyper-glycosylation from P. pastoris brings immunogenicity and low purification recovery rate. To overcome this disadvantage, in this study, we constructed an rhIFN-λ1 mutant (rhIFN-λ1-Nm) devoid of the potential N-glycosylation sites by site-directed mutagenesis. rhIFN-λ1-Nm was successfully expressed and secreted extracellularly in P. pastoris (GS115) using methanol inducible AOX1 promoter with α-mating factor signal sequence. rhIFN-λ1-Nm was purified and characterized. There was no significant difference between rhIFN-λ1-Nm and rhIFN-λ1 in structure and bioactivity. The molecular weight was low after N-glycosylation mutation whereas the glycosylation was much lower. The mutational rhIFN-λ1 (rhIFN-λ1-Nm) could legitimately be developed as substitutes for rhIFN-λ1, and thus it may be developed into a more promising therapeutic reagent in the future.

Postoperative urinary retention after inguinal hernia repair: a single institution experience

PURPOSE

Inguinal hernia repair is a common general surgery procedure with low morbidity. However, postoperative urinary retention (PUR) occurs in up to 22% of patients, resulting in further extraneous treatments.This single institution series investigates whether patient comorbidities, surgical approaches, and anesthesia methods are associated with developing PUR after inguinal hernia repairs.

METHODS

This is a single institution retrospective review of inguinal hernia from 2012 to 2015. PUR was defined as patients without a postoperative urinary catheter who subsequently required bladder decompression due to an inability to void. Univariate and multivariate logistic regressions were performed to quantify the associations between patient, surgical, and anesthetic factors with PUR. Stratification analysis was conducted at age of 50 years.

RESULTS

445 patients were included (42.9% laparoscopic and 57.1% open). Overall rate of PUR was 11.2% (12% laparoscopic, 10.6% open, and p = 0.64). In univariate analysis, PUR was significantly associated with patient age >50 and history of benign prostatic hyperplasia (BPH). Risk stratification for age >50 revealed in this cohort a 2.49 times increased PUR risk with lack of intraoperative bladder decompression (p = 0.013).

CONCLUSIONS

At our institution, we found that patient age, history of BPH, and bilateral repair were associated with PUR after inguinal hernia repair. No association was found with PUR and laparoscopic vs open approach. Older males may be at higher risk without intraoperative bladder decompression, and therefore, catheter placement should be considered in this population, regardless of surgical approach.

Effect of ultrasound and heat on percutaneous absorption of l-ascorbic acid: human in vitro studies on Franz cell and Petri dish systems

OBJECTIVE

Percutaneous absorption of l-ascorbic acid (LAA) is limited due to its high hydrophilicity and low stability. Here, we investigated the effect of post-dosing sonophoresis (329 kHz, 20 mW cm^-2 ) and heat (36°C) on transdermal delivery of LAA.

METHODS

Ultrasound/heat, heat and control treatments were applied on skin surface for 2 and 5 min after topical application of C14-labelled LAA aqueous solution. After 15 min post-exposure, radioactivity was measured in tape-striped stratum corneum (TS-SC), epidermis, dermis and receptor fluid. As Franz diffusion cell model may have different acoustic response than in vivo human tissues, a novel Petri dish model was developed and compared with Franz cell model on the effects of ultrasound/heat treatment on the skin permeability.

RESULTS

Five-min ultrasound/heat treatment significantly accelerated skin absorption/penetration of LAA; 2-min treatment showed no enhancement effect on Franz diffusion cell model at the end of experiment. The use of Petri dish model significantly increased LAA concentrations in epidermis after 5 min of ultrasound/heat treatment, compared to the results of Franz cell model.

CONCLUSION

Combination of ultrasound (329 kHz, 20 mW cm^-2 ) and heat (36°C) significantly enhanced LAA transdermal penetration, when the time of treatment was sufficient (5 min). As Petri dish model was designed to simulate acoustic respond of dense human tissue to ultrasound, the difference between Franz cell and Petri dish models suggests that the enhancement effect of ultrasound/heat on skin penetration in vivo may be greater than that determined on in vitro Franz cell model.

Therapeutic hypothermia protects against ischemia-induced impairment of synaptic plasticity following juvenile cardiac arrest in sex-dependent manner

Pediatric cardiac arrest (CA) often leads to poor neurologic outcomes, including deficits in learning and memory. The only approved treatment for CA is therapeutic hypothermia, although its utility in the pediatric population remains unclear. This study analyzed the effect of mild therapeutic hypothermia after CA in juvenile mice on hippocampal neuronal injury and the cellular model of learning and memory, termed long-term potentiation (LTP). Juvenile mice were subjected to cardiac arrest and cardiopulmonary resuscitation (CA/CPR) followed by normothermia (37°C) and hypothermia (30°C, 32°C). Histological injury of hippocampal CA1 neurons was performed 3days after resuscitation using hematoxylin and eosin (H&E) staining. Field excitatory post-synaptic potentials (fEPSPs) were recorded from acute hippocampal slices 7days after CA/CPR to determine LTP. Synaptic function was impaired 7days after CA/CPR. Mice exposed to hypothermia showed equivalent neuroprotection, but exhibited sexually dimorphic protection against ischemia-induced impairment of LTP. Hypothermia (32°C) protects synaptic plasticity more effectively in females, with males requiring a deeper level of hypothermia (30°C) for equivalent protection. In conclusion, male and female juvenile mice exhibit equivalent neuronal injury following CA/CPR and hypothermia protects both males and females. We made the surprising finding that juvenile mice have a sexually dimorphic response to mild therapeutic hypothermia protection of synaptic function, where males may need a deeper level of hypothermia for equivalent synaptic protection.

Effects of intravenous analgesia with combined dezocine and butorphanol on postoperative cognitive function in elderly patients

The aim of this study was to observe the analgesic effects of the combination of dezocine and butorphanol on postoperative cognitive function in elderly patients. Forty elderly patients undergoing upper abdominal surgeries or thoracotomies with general anesthesia were randomly divided into the dezocine and butorphanol group or the butorphanol group (20 patients per group). A visual analog scale was used to evaluate analgesia and the degree of malignant vomiting. The Ramsay scoring method was used to evaluate sedation. The Mini-Mental State Examination (MMSE) was used to evaluate cognitive function. Forty-eight hours after the operation, the pain score of the dezocine and butorphanol group (means ± SD, 1.75 ± 0.44) was lower than that of the butorphanol group (2.25 ± 0.79; P < 0.05), and the nausea and vomiting score of the dezocine and butorphanol group (0) was lower than that of the butorphanol group (0.70 ± 1.30; P < 0.05). Six hours after the operation, the sedative score of the butorphanol group (3.75 ± 0.79) was higher than that of the dezocine and butorphanol group (2.15 ± 0.75; P < 0.05). Compared to 1 day before the operation, the MMSE scores of both groups decreased 6 h after the operation, and the MMSE score of the butorphanol group (15.00 ± 2.00) was lower than that of the dezocine and butorphanol group (20.95 ± 1.54; P < 0.05). Dezocine and butorphanol analgesia had transient effects on postoperative cognitive function in elderly patients, and the effect of the combination was superior than butorphanol only.

Emerging therapies for the treatment of ungual onychomycosis

INTRODUCTION

Onychomycosis, a common fungal infection in the finger and toe nails, affects approximately 2-8% of the worldwide population. Fungal infection is more complicated in those who suffer from conditions, such as diabetes, peripheral vascular diseases and compromised immune diseases.

AREA COVERED

Onychomycosis treatment has been classified on the basis of location of infection in the toes and fingers and infectious agents (dermatophytes fungi, yeast and non-dermatophyte molds). In this review, the available therapies (traditional and device based) and their limitations for the treatment of onychomycosis have been discussed.

EXPERT OPINION

The success rate with topical nail products has been minimal. The main reason for this poor success rate could be attributed to the lack of complete understanding of the pathophysiology of the disease and clinical pharmacokinetic data of drugs in the infected nail apparatus.

Effect of Tanshinone IIA intrathecal injections on pain and spinal inflammation in mice with bone tumors

The study aimed to investigate the effect of intrathecal injections of Tanshinone IIA on thermal hyperalgesia in a mouse model of bone cancer-pain. Spinal IL-1β, IL-6, TNF-α expression levels were analyzed. C3H/HeNCrlVr male mice were assigned to groups that either received dose-dependent injections of Tanshinone IIA, or the DMSO + Sham, Tanshinone IIA + Sham, DMSO + Tumor, and Control groups. Paw withdrawal thermal latency (PWTL) was measured with a radiant heat stimulus and mRNA expression levels were determined using real-time PCR. Fourteen days post-injection, PWTL in the DMSO + Tumor group was lower than that in the controls (P < 0.05). Twenty-one days post-injection, compared with the Control group, there was no significant difference in PWTL and IL-1β, IL-6, and TNF-α expression levels between the Tanshinone IIA + Sham and DMSO + Sham groups (P > 0.05). PWTL in the DMSO + Tumor group was significantly lower than the Control group (P < 0.05), while the expression levels of IL-1β, IL-6, and TNF-α were significantly higher than controls. Compared with the DMSO + Tumor group, PWTLs were higher in the Tanshinone IIA - 20-μg and 40-μg groups, while expression levels of IL-1β, IL-6, and TNF-α were significantly lower (P < 0.05). These measures were not significantly different between the Tanshinone IIA 10 μg and the DMSO + Tumor groups (P > 0.05). In conclusion, Tanshinone IIA may inhibit the release of inflammatory cytokines, such as, IL-1 β, IL-6 α, TNF-α.

Suppression of hepatocellular carcinoma proliferation and hepatitis B surface antigen secretion with interferon-λ1 or PEG-interferon-λ1

Hepatocellular carcinoma (HCC) is a common cancer associated with chronic hepatitis B virus (HBV) infection. Conventional interferon-α (IFN-α) and pegylated IFNs (PEG-IFNs) approved for chronic HBV infection treatment can reduce the risk of HCC but are not suitable for the majority of patients and cause significant side effects. IFN-λ1 is a type III IFN with antiviral, antiproliferative, and immunomodulatory functions similar to type I IFNs but with fewer side effects. However, the tolerability and antitumor activity of PEG-IFN-λ1 in HCC xenograft mice are unknown. In vitro IFN-λ1 treatment of Hep3B and Huh7 human hepatoma cell lines increased MHC class I expression, activated JAK-STAT signaling pathways, induced IFN-stimulated gene expression, and inhibited hepatitis B surface antigen (HBsAg) expression. IFN-λ1 treatment also caused 23.2 and 19.9% growth inhibition of Hep3B and Huh7 cells, respectively, and promoted cellular apoptosis. PEG-IFN-λ1, but not IFN-λ1 treatment, significantly suppressed tumor growth (P=0.002) and induced tumor cell apoptosis in a Hep3B cell xenograft mouse model without significant weight loss or toxicity. PEG-IFN-λ1 also significantly inhibited (P=0.000) serum HBsAg secretion from Hep3B xenograft tumors in vivo. Thus, PEG-IFN-λ1 can suppress Hep3B xenograft tumor growth and inhibit HBsAg production and may be a potential treatment for HBV-related HCC.

High-level expression, purification and characterization of active human C1q and tumour necrosis factor-related protein-1 in Escherichia coli

C1q and tumour necrosis factor-related proteins (CTRPs) are a family of adiponectin paralogues. CTRP1 plays important biological functions in diabetes, obesity and hypertension. To further explore the physiological roles of human CTRP1 and its mechanisms of action, hCTRP1 gene was expressed in Escherichia coli. In the E. coli expression system, a large amount of soluble thioredoxin (Trx)-hCTRP1 fusion protein could be produced using the expression plasmid pET32a (+) and induction with IPTG at 18°C, which accounts about 20% of the total soluble bacterial proteins. The recombinant Trx-hCTRP1 fusion protein was purified to an approx. 95% purity using Ni-NTA affinity chromatography and Superdex G-75 column with a yield of about 28-mg protein from 1-l bacterial cultures. The purified recombinant Trx-hCTRP1 was shown to be active under in vivo and in vitro assay conditions.

SIGNIFICANCE AND IMPACT OF THE STUDY

CTRP1 plays important biological functions and warrants further investigation. However, large-scale production of recombinant CTRP1 has been technically challenging, which becomes a major obstacle in the structural and functional analysis of this important family of proteins. To explore the possible clinical applications and mechanisms of its action, an efficient method to produce large amounts of active recombinant human CTRP1 is necessary. This study should facilitate basic functional and pharmacological studies of this important protein family.

Clinical and genetic features of 5 Chinese patients with X-linked lymphoproliferative syndrome

In this study, we report the clinical and genetic features of Chinese patients with X-linked lymphoproliferative syndrome (XLP). Male patients with fulminant infectious mononucleosis (FIM), Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) or persistent EBV viremia were enrolled in this study. Direct sequencing was used to detect SH2D1A/XIAP gene mutations. The patients' clinical features were assessed by retrieval of data from medical records. Twenty-one male patients with FIM, EBV-associated HLH or persistent EBV viremia were evaluated. Four patients had SH2D1A mutations, and one patient had an XIAP mutation. All five of these patients had symptoms of HLH and EBV infection. Among the five patients, the youngest one was only 1 month old at onset. One patient exhibited hypogammaglobulinemia. Of four patients evaluated for immunological function, all exhibited reduced CD4/CD8 ratios. Three patients had rapid disease progression and died. One patient received haematopoietic stem cell transplantation and is well. The overall clinical phenotypes of Chinese patients with XLP matched previous reports. For patients with severe EBV-associated HLH, our results indicate the need to examine the possibility of XLP.

Antitumor activities of recombinant human interferon (IFN)-λ1 in vitro and in xenograft models in vivo for colon cancer

Interferon (IFN)-λ1, as a newly identified IFN, interacts with the structurally unique IFN-λ1 receptor complex and exhibits antiviral and antiproliferation effects. The major focus of our work was to study the antitumor activities of recombinant human IFN-λ1 (rhIFN-λ1) in vivo and in vitro. The MTT analysis showed that rhIFN-λ1 inhibited the proliferation of HCT116 cells in a dose-dependent manner, but with a less efficacy in HT29 cells than HCT116 cells. IFN-λ1 also activated the STATs and induced apoptosis in both types of cells. In the in vivo study, we found that rhIFN-λ1 suppressed tumor growth in a dose-dependent fashion, with an inhibition rate of 52% of HCT116 (P<0.01) and 56% of HT29 (P<0.01). These results indicate that rhIFN-λ1 could be a new potential IFN reagent for cancer therapy.

Metallic liquids and glasses: atomic order and global packing

In this Letter, we have revealed the common structural behavior of metallic glasses through scrutinizing the evolution of pair distribution functions from metallic liquids to glasses and statistically analyzing pair distribution functions of 64 metallic glasses. It is found that the complex atomic configuration in metallic glasses can be interpreted globally as a combination of the spherical-periodic order and local translational symmetry. The implications of our study suggest that the glass transition could be visualized mainly as a process involving in local translational symmetry increased from the liquid to glassy states.

Stronger in vitro phagocytosis by monocytes-macrophages is indicative of greater pathogen clearance and antibody levels in vivo

Monocytes-macrophages are crucial players in specific and nonspecific immune responses to protect organisms from invasion of bacteria or viruses. In this study, monocytes in circulation from 2 lines of Silky and Starbro chickens with different disease resistance were separated and cultured in vitro. After identification with acridine orange (AO), Giemsa staining, and CD14 immunostaining, monocytes-macrophages were used for adherence and phagocytosis test. The overall percentages of adherence of Silky monocytes was 1.5 times greater than that of Starbro (P < 0.01), which were 26.85% +/- 8.24% and 18.34% +/- 8.15%, respectively (mean +/- SD). The monocytes-macrophages phagocytic index, phagocytic product, and percentage of phagocytosis in Silkies were greater than in Star-bros, respectively. The difference of phagocytic index was significant (P < 0.05), that is, 3.70 +/- 1.75 and 1.97 +/- 0.31, respectively (mean +/- SD). Then, 20 Silkies were divided into 2 groups according to phagocytic index: high phagocytic index (HPI) group and low phagocytic index (LPI) group, to study the relationship between phagocytic activity in vitro and pathogen clearance. After being challenged against Salmonella Pullorum C79-13, the Silky birds with HPI produced a 3-fold greater level of specific antibodies compared with those with LPI (P < 0.01), 50.21 +/- 6.67 and 16.85 +/- 4.52, respectively (mean +/- SD). In contrast to LPI birds, HPI birds shed less Salmonella Pullorum bacteria (P < 0.05), that is, 168.98 x 10(8) +/- 294.74 x 10(8) compared to 385.40 x 10(8) +/- 399.94 x 10(8) (mean +/- SD), and the shedding peak of Salmonella Pullorum in the test span appeared 4 d earlier. These results indicated that phagocytosis of monocytes-macrophages had strong effects on antibody titer and bacteria shedding postchallenge, which could be used to predict the disease resistance in animals.

Elevated plasma osteopontin level is predictive of cirrhosis in patients with hepatitis B infection

BACKGROUND

Osteopontin (OPN) was shown to play an important role in the pathogenesis of various inflammatory and fibrotic processes and elevated in fibrotic liver of mouse model. However, the significance of OPN in hepatitis B virus (HBV)-induced liver cirrhosis (LC) remains unclear and is therefore evaluated in this study.

METHODS

Thirty-nine patients with HBV-induced LC, 30 patients with HBV infection but without cirrhosis, 11 patients with HBV-related hepatocellular carcinoma (HCC) and 14 additional healthy controls were enrolled in this study. Plasma levels of OPN were measured with enzyme-linked immunosorbent assay and the relationship between OPN and clinical parameters was evaluated.

RESULTS

When compared to HBV infection group (median 2.16 ng/ml), plasma levels of OPN were significantly increased in cirrhosis (4.52 ng/ml, p < 0.001) and cancer group (13.38 ng/ml, p < 0.001). The OPN level was correlated with the severity of liver damage according to Child-Pugh classification (p = 0.003). It showed at least comparable sensitivity and specificity to predict cirrhosis as aspartate aminotransferase to platelet ratio index, a previously established non-invasive serum marker of cirrhosis.

CONCLUSIONS

These data suggest that OPN could be used to evaluate the existence of LC, as OPN has previously been reported to be increased in the HCC; this unique feature makes OPN a promising candidate for prediction biomarker in the long-time surveillance of patients with HBV infection to evaluate the risk of cirrhosis and cancer.

Skin decontamination of glyphosate from human skin in vitro

This study compared three model decontaminant solutions (tap water, isotonic saline, and hypertonic saline) for their ability to remove a model herbicide (glyphosate) from an in vitro human skin model. Human cadaver skin was dosed (approximately 375microg) of [14C]-glyphosate on 3cm2 per skin. After each exposure time (1, 3, and 30min post-dosing, respectively), the surface skin was washed three times (4ml per time) with each solution. After washing, the skin was stripped twice with tape discs. Lastly, the wash solutions, strippings, receptor fluid, and remainder of skin were liquid scintillation analyzer counted to determine the amount of glyphosate. There were no statistical differences among these groups at any time points. The total mass balance recovery at three time exposure points was between 94.8% and 102.4%. The wash off rates (glyphosate in wash solutions) at three different exposure times is 79-101.2%. Thus the three tested decontaminants possess similar effectiveness in removing glyphosate from skin. This in vitro model is not only economic and rapid, but also provides quantitative data that may aid screening for optimal decontaminants.

NifL, an antagonistic regulator of NifA interacting with NifA

Nitrogen fixation (nif) genes of diazotrophic enteric bacteria,Enterobacter cloacae orKlebsiella pneumoniae, are regulated bynif LA operon, in which thenif A product, NifA positively regulatesnif gene transcription, whereas the nifL product NifL represses it under oxygen or in excess of fixed nitrogen. Two-hybrid system was used to detect the possible interaction between NifA and NifL. The preliminary results illustrate that NifL does interact with NifA. The interaction between NifL and NtrC has also been shown.

In vitro model for decontamination of human skin: Formaldehyde

Decontamination of a chemical from skin is often an emergency measure. This study utilized an in vitro model to compare the decontamination capacity of three model decontaminant solutions (tap water, isotonic saline, and hypertonic saline). Human cadaver skin was dosed (approximately 0.25 microg on 3 cm(2) per skin) with radio-labeled [(14)C]-formaldehyde. After a defined exposure time (1, 3, and 30 min post-dosing, respectively), the surface skin was washed three times (4ml per time) with each solution. After washing, the skin was stripped with tape discs twice. Lastly, the wash solutions, strippings, receptor fluid, and remainder of skin were liquid scintillation analyzer counted to determine the amounts of formaldehyde. Additionally, an evaporation test at different exposure times (1min, 3min, 15min, 30min, and 60min, respectively) was conducted to monitor formaldehyde % evaporation. There were no statistical differences among these groups except isotonic saline, at 3min post-exposure (in wash solutions), showed a significantly difference (p<0.05) when compared to tap water. Formaldehyde % evaporation increased linearly with extending application times, and were 7.7%, 13.6%, 19.7%, 24.4%, and 35.9% (1min, 3min, 15min, 30min, and 60min, respectively). This data suggests that isotonic saline may be effective in removing formaldehyde from skin. However, results from this model need validation in vivo. The model may provide a facile and robust method of accelerating knowledge of decontamination mechanism and lead to enhanced efficacy.

Pharmacokinetic and local tissue disposition of [14C]sodium diclofenac following iontophoresis and systemic administration in rabbits

The systemic pharmacokinetics and local drug distribution of sodium diclofenac in skin and underlying tissues was studied. Iontophoresis facilitated local and systemic delivery of diclofenac sodium compared with passive diffusion. The maximum plasma concentration of sodium diclofenac was achieved within 1 h of iontophoresis, and the delivery was proportional to applied current density (371 +/- 141 and 132 +/- 62 microg/L at 0.5 and 0.2 mA/cm(2), respectively). The in vivo delivery efficiency for diclofenac in rabbit was 0.15 mg/mA.h. The concentrations of sodium diclofenac in the skin, subcutaneous tissue, and muscle beneath the drug application site (cathode) were significantly greater than plasma concentrations and concentrations of drug in similar tissues at the untreated sites. The results thus suggest that the cutaneous microvasculature is not always a perfect "sink" and that transdermal iontophoresis facilitated the direct penetration of diclofenac sodium to deeper tissues. No skin irritation was observed up to 0.5 mA/cm(2) current density and 7 mg/mL sodium diclofenac concentration.

Taurine protects against carbon tetrachloride toxicity in the cultured neurons and in vivo

Carbon tetrachloride (CCl4) has been found to induce cellular damage by generating oxygen free radicals. A study was carried out to investigate the effects of taurine (extracted from Pegasus laternarius Cuvier) on CCl4 intoxicated cultured neurons. CCl4 application (0.4 mmol x l(-1), 0.8 mmol x l( -1), 1.2 mmol x l (-1) and 1.6 mmol x l(-1 )) increased the lipid peroxidation product and decreased glutathione peroxidase (GPx) activity significantly in a concentration dependent manner. Pretreatment of cultures with taurine (10 micromol x l(-1), 30 micromol x l(-1) and 60 micromol x l(-1)) prevented the loss of GPx activity and lipid peroxidation. The effects of three different dosages of taurine (10 mg/kg body wt., 20 mg/kg body wt. and 40 mg/ kg body wt.) for 45 days on the activities of superoxide dismutase and glutathione peroxidase were examined in the cerebrum, cerebellum and medulla of normal and CCl4 treated mice. Treatment of mice with taurine provided protection against CCl4 toxicity as was evident by lipid peroxide status. Taurine was not so successful at inducing the activity of SOD in normal animals except in the medulla where it could increase the activity of SOD (p < 0.05). Taurine induces the GPx activity in a dose dependent manner in all regions of the brain studied. Also in the CCl4 poisoned mice taurine could augment the status of GPx activity in a dose dependent manner. Hence it is concluded that taurine can protects neurons from the oxidative stress induced by CCl4.

Assessment of the percutaneous absorption of trichloroethylene in rats and humans using MS/MS real-time breath analysis and physiologically based pharmacokinetic modeling

The development and validation of noninvasive techniques for estimating the dermal bioavailability of solvents in contaminated soil and water can facilitate the overall understanding of human health risk. To assess the dermal bioavailability of trichloroethylene (TCE), exhaled breath was monitored in real time using an ion trap mass spectrometer (MS/MS) to track the uptake and elimination of TCE from dermal exposures in rats and humans. A physiologically based pharmacokinetic (PBPK) model was used to estimate total bioavailability. Male F344 rats were exposed to TCE in water or soil under occluded or nonoccluded conditions by applying a patch to a clipper-shaved area of the back. Rats were placed in off-gassing chambers and chamber air TCE concentration was quantified for 3-5 h postdosing using the MS/MS. Human volunteers were exposed either by whole-hand immersion or by attaching patches containing TCE in soil or water on each forearm. Volunteers were provided breathing air via a face mask to eliminate inhalation exposure, and exhaled breath was analyzed using the MS/MS. The total TCE absorbed and the dermal permeability coefficient (K(P)) were estimated for each individual by optimization of the PBPK model to the exhaled breath data and the changing media and/or dermal patch concentrations. Rat skin was significantly more permeable than human skin. Estimates for K(P) in a water matrix were 0.31 +/- 0.01 cm/h and 0.015 +/- 0.003 cm/h in rats and humans, respectively. K(P) estimates were more than three times higher from water than soil matrices in both species. K(P) values calculated using the standard Fick's Law equation were strongly affected by exposure length and volatilization of TCE. In comparison, K(P) values estimated using noninvasive real-time breath analysis coupled with the PBPK model were consistent, regardless of volatilization, exposure concentration, or duration.

A real-time in-vivo method for studying the percutaneous absorption of volatile chemicals

Realistic estimates of percutaneous absorption following exposures to solvents in the workplace, or through contaminated soil and water, are critical to understanding human health risks. A method was developed to determine dermal uptake of solvents under non-steady-state conditions using real-time breath analysis in rats, monkeys, and humans. The exhaled breath was analyzed using an ion-trap mass spectrometer, which can quantitate chemicals in the exhaled breath stream in the 1-5 ppb range. The resulting data were evaluated using physiologically-based pharmacokinetic (PBPK) models to estimate dermal permeability constants (Kp) under various exposure conditions. The effects of exposure matrix (soil versus water), occlusion versus non-occlusion, and species differences on the absorption of methyl chloroform, trichloroethylene, and benzene were compared. Exposure concentrations were analyzed before and at 0.5-hour intervals throughout the exposures. The percentage of each chemical absorbed and the corresponding Kp were estimated by optimization of the PBPK model to the medium concentration and the exhaled-breath data. The method was found to be sufficiently sensitive for animal and human dermal studies at low exposure concentrations over small body surface areas, for short periods, using non-steady-state exposure conditions.

Utility of real time breath analysis and physiologically based pharmacokinetic modeling to determine the percutaneous absorption of methyl chloroform in rats and humans

Due to the large surface area of the skin, percutaneous absorption has the potential to contribute significantly to the total bioavailability of some compounds. Breath elimination data, acquired in real-time using a novel MS/MS system, was assessed using a PBPK model with a dermal compartment to determine the percutaneous absorption of methyl chloroform (MC) in rats and humans from exposures to MC in non-occluded soil or occluded water matrices. Rats were exposed to MC using a dermal exposure cell attached to a clipper-shaved area on their back. The soil exposure cell was covered with a charcoal patch to capture volatilized MC and prevent contamination of exhaled breath. This technique allowed the determination of MC dermal absorption kinetics under realistic, non-occluded conditions. Human exposures were conducted by immersing one hand in 0.1% MC in water, or 0.75% MC in soil. The dermal PBPK model was used to estimate skin permeability (Kp) based on the fit of the exhaled breath data. Rat skin K(p)s were estimated to be 0.25 and 0.15 cm/h for MC in water and soil matrices, respectively. In comparison, human permeability coefficients for water matrix exposures were 40-fold lower at 0.006 cm/h. Due to evaporation and differences in apparent Kp, nearly twice as much MC was absorbed from the occluded water (61.3%) compared to the non-occluded soil (32.5%) system in the rat. The PBPK model was used to simulate dermal exposures to MC-contaminated water and soil in children and adults using worst-case EPA default assumptions. The simulations indicate that neither children nor adults will absorb significant amounts of MC from non-occluded exposures, independent of the length of exposure. The results from these simulations reiterate the importance of conducting dermal exposures under realistic conditions.

Improvement of impaired memory in mice by taurine

Taurine was extracted from Pegasus laternarius Cuvier to study its effects on learning and memory in mice. Mice were treated with different doses of taurine (10 mg/kg, 20 mg/kg, 40 mg/kg). The mice were treated with various chemical agents (pentobarbital, cycloheximide, sodium nitrite, alcohol) to disrupt the normal memory process. We measured the effect of taurine on step-down latency (SDL) and escape latency (EL) in a passive avoidance task after 10 or 30 days. Treatment with taurine alone did not change either SDL or EL. Taurine protected mice from the memory disruption induced by alcohol, pentobarbital, sodium nitrite, and cycloheximide but had no obvious effect on motor coordination, exploratory activity, or locomotor activity as measured using the rota-rod test and the hole board test. We conclude that taurine can be effective in attenuating the amnesia produced by alcohol, pentobarbital, cycloheximide, and sodium nitrite without compromising the behavioral aspects of the animals tested.

HPLC-accelerator MS measurement of atrazine metabolites in human urine after dermal exposure

Metabolites of atrazine were measured in human urine after dermal exposure using HPLC to separate and identify metabolites and accelerator mass spectrometry (AMS) to quantify them. Ring-labeled [14C]atrazine was applied for 24 h with a dermal patch to human volunteers at low (0.167 mg, 6.45 muCi) and high (1.98 mg, 24.7 muCi) doses. Urine was collected for 7 days. The urine was centrifuged to remove solids, and the supernatant was measured by liquid scintillation counting prior to injection on the HPLC to ensure that < 0.17 Bq (4.5 pCi) was injected on the column. A reversed-phase gradient of 0.1% acetic acid in water and 0.1% acetic acid in acetonitrile became less polar with increasing time and separated the parent compound and major atrazine metabolites over 31 min on an octadecylsilane column. Peaks were identified by coelution with known standards. Elution fractions were collected in 1-min increments; half of each fraction was analyzed by AMS to obtain limits of quantitation of 14 amol. Mercapturate metabolites of atrazine and dealkylated atrazine dominated the early metabolic time points, accounting for approximately 90% of the 14C in the urine. No parent compound was detected. The excreted atrazine metabolites became more polar with increasing time, and an unidentified polar metabolite that was present in all samples became as prevalent as any of the known ring metabolites several days after the dose was delivered. Knowledge of metabolite dynamics is crucial to developing useful assays for monitoring atrazine exposure in agricultural workers.

In vivo skin decontamination of methylene bisphenyl isocyanate (MDI): soap and water ineffective compared to polypropylene glycol, polyglycol-based cleanser, and corn oil

In the home and workplace, decontamination of a chemical from skin is traditionally done with a soap-and-water wash, although some workplaces may have emergency showers. It has been assumed that these procedures are effective, yet workplace illness and even death occur from chemical contamination. Water, or soap and water, may not be the most effective means of skin decontamination, particularly for fat-soluble materials. This study was undertaken to help determine whether there are more effective means of removing methylene bisphenyl isocyanate (MDI), a potent contact sensitizer, from the skin. MDI is an industrial chemical for which skin decontamination, using traditional soap and water and nontraditional polypropylene glycol, a polyglycol-based cleanser (PG-C), and corn oil were all tried in vivo on the rhesus monkey, over 8 h. Water, alone and with soap (5% and 50% soap), were partially effective in the first h after exposure, removing 51-69% of the applied dose. However, decontamination fell to 40-52% at 4 h and 29-46% by 8 h. Thus, the majority of MDI was not removed by the traditional soap-and-water wash; skin tape stripping after washing confirmed that MDI was still on the skin. In contrast, polypropylene glycol, PG-C, and corn oil all removed 68-86% of the MDI in the first h, 74-79% at 4 h, and 72-86% at 8 h. Statistically, polypropylene glycol, PG-C, and corn oil were all better (p < 0.05) than soap and water at 4 and 8 h after dose application. These results indicate that a traditional soap-and-water wash and the emergency water shower are relatively ineffective at removing MDI from the skin. More effective decontamination procedures, as shown here, are available. These procedures are consistent with the partial miscibility of MDI in corn oil and polyglycols.

In vivo bioavailability and metabolism of topical diclofenac lotion in human volunteers

PURPOSE

The primary objective of this study was to determine the rate and extent of transdermal absorption for systemic delivery of diclofenac from Pennsaid (Dimethaid Research, Inc.) topical lotion into the systemic circulation after the lotion was applied to human volunteers, in an open treatment, non-blinded, non-vehicle controlled study. In addition, the in vivo metabolism of this topical diclofenac lotion has also been studied.

METHODS

Human volunteers were dosed with topical [14C]-diclofenac sodium 1.5% lotion on the knee for 24 h. Sequential time blood and urine samples were taken to determine pharmacokinetics, bioavailability and metabolism.

RESULTS

Topical absorption was 6.6% of applied dose. Peak plasma 14C occurred at 30 h after dosing, and peak urinary 14C excretion was at 24-48 h. The urinary 14C excretion pattern exhibits more elimination towards 24 h and beyond, as opposed to early urinary 14C excretion. This suggests a continuous delivery of [14C]-diclofenac sodium from the lotion into and through skin which only ceased when the dosing site was washed. Skin surface residue at 24 h was 26 +/- 9.5% dose (remainder assumed lost to clothing and bedding). Extraction of metabolites from urine amounted to 7.4-22.7% in untreated urine, suggesting substantial diclofenac metabolism to more water soluble metabolites, probably conjugates, which could not be extracted by the method employed. Two Dimensional TLC analysis of untreated urine showed minimal or no diclofenac, again emphasizing the extensive in vivo metabolism of this drug. Treatment of the same urine samples with the enzymes sulfatase and beta-glucuronidase showed a substantial increase in the extractable material. Three spots were consistently present in each sample run, namely diclofenac, 3'hydroxy diclofenac and an intermediate polar metabolite (probably a hydroxylated metabolite). Therefore, there was significant sulfation and glucuronidation of both diclofenac and numerous hydroxy metabolites of diclofenac, but many of the metabolites/conjugates remain unidentified. CONCLUSIONS; There was a continuous delivery of diclofenac sodium from the lotion into and through the skin, which ceased after the dosing site was washed. The majority of the material excreted in the urine were conjugates of hydroxylated metabolites, and not the parent chemical, although further identification is required.