Next generation physiologically based kinetic (NG-PBK) models in support of regulatory decision making.

The fields of toxicology and chemical risk assessment seek to reduce, and eventually replace, the use of animals for the prediction of toxicity in humans. In this context, physiologically based kinetic (PBK) modelling based on in vitro and in silico kinetic data has the potential to a play significant role in reducing animal testing, by providing a methodology capable of incorporating in vitro human data to facilitate the development of in vitro to in vivo extrapolation of hazard information. In the present article, we discuss the challenges in: 1) applying PBK modelling to support regulatory decision making under the toxicology and risk-assessment paradigm shift towards animal replacement; 2) constructing PBK models without in vivo animal kinetic data, while relying solely on in vitro or in silico methods for model parameterization; and 3) assessing the validity and credibility of PBK models built largely using non-animal data. The strengths, uncertainties, and limitations of PBK models developed using in vitro or in silico data are discussed in an effort to establish a higher degree of confidence in the application of such models in a regulatory context. The article summarises the outcome of an expert workshop hosted by the European Commission Joint Research Centre (EC-JRC) - European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), on "Physiologically-Based Kinetic modelling in risk assessment - reaching a whole new level in regulatory decision-making" held in Ispra, Italy, in November 2016, along with results from an international survey conducted in 2017 and recently reported activities occurring within the PBK modelling field. The discussions presented herein highlight the potential applications of next generation (NG)-PBK modelling, based on new data streams.

[The effect of WT1 expression on the prognosis of allogeneic hematopoietic stem cell transplantation in acute leukemia].

Objective: To study the effect of WT1 expression on the prognosis of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in acute leukemia (AL) and its significance as molecular marker to dynamically monitor minimal residual disease (MRD) . Methods: Retrospectively analyzed those AL patients who underwent allo-HSCT in the First Hospital Affiliated to Zhejiang University School of Medicine during Jan 2016 to Dec 2017, a total number of 314 cases, 163 males and 151 females, median age was 30 (9-64) years old. Comparing the difference of WT1 expression at diagnosed, pre-HSCT and after HSCT. Using the receiver operating characteristic (ROC) curve to determine the WT1 threshold at different time so as to predict relapse. The threshold of WT1 expression before transplantation was 1.010%, within 3 months after HSCT was 0.079% and 6 months after HSCT was 0.375%. According to these thresholds, WT1 positive patients were divided into low expression groups and high expression groups. Analyzed the relationship between overall survival (OS) , disease-free survival (DFS) , cumulative incidence of relapse (CIR) and WT1 expression. Results: The OS and DFS of high expression group pre-HSCT were lower than low expression group [69.2% (9/13) vs 89.1% (57/64) , χ(2)=4.086, P=0.043; 53.8% (7/13) vs 87.5% (56/64) , χ(2)=9.766, P=0.002], CIR was higher than low expression group [30.8% (4/13) vs 7.8% (5/64) , P=0.017]. There was no significant difference of OS and DFS between high expression and low expression group of 3 months after HSCT (P=0.558, P=0.269) . The OS and DFS of high expression group of 6 months after transplantation were both lower than low expression group (P=0.049, P=0.035) . Multivariate analysis showed that WT1>0.375% when 6 months after transplantation was the only independent prognostic factor for shorter DFS (P=0.022) . There was no statistically significant difference in CIR between the high-expression group and the low-expression group 3 months after transplantation and 6 months after transplantation (P=0.114, P=0.306) . Conclusion: High expression of WT1 before and after HSCT was an adverse prognosis factor. It is of clinical practical value to use WT1 as a transplant recommendation index for patients with acute leukemia and as a marker to monitor MRD dynamically.

Intrinsic functional plasticity of the sensory-motor network in patients with cervical spondylotic myelopathy.

Several neuroimaging studies have suggested brain reorganisation in patients with cervical spondylotic myelopathy (CSM); however, the changes in spontaneous neuronal activity that are associated with connectedness remain largely unknown. In this study, functional connectivity strength (FCS), a data-driven degree centrality method based on a theoretical approach, was applied for the first time to investigate changes in the sensory-motor network (SMN) at the voxel level. Comparatively, CSM not only showed significantly decreased FCS in the operculum-integrated regions, which exhibited reduced resting-state functional connectivity (rsFC) around the Rolandic sulcus, but it also showed increased FCS in the premotor, primary somatosensory, and parietal-integrated areas, which primarily showed an enhanced rsFC pattern. Correlation analysis showed that altered FCS (in the left premotor-ventral/precentral-operculum, right operculum-parietale 4, and right S1) was associated with worsening Japanese Orthopaedic Association scores and that the rsFC pattern was influenced by cervical cord micro-structural damage at the C2 level. Together, these findings suggest that during myelopathy, the intrinsic functional plasticity of the SMN responds to the insufficient sensory and motor experience in CSM patients. This knowledge may improve our understanding of the comprehensive functional defects found in CSM patients and may inspire the development of new therapeutic strategies in the future.

Comparing performance of Chromameter®, Mexameter® and full-field laser perfusion imaging for measurement of ultraviolet B light-induced erythema.

Erythema induced by ultraviolet (UV)B light is a common skin reaction. Currently, three techniques, the Chromameter(®) CR-400, the Mexameter(®) MX16 and full-field laser perfusion imaging (FLPI), are widely used for dermatological evaluation of UVB-induced erythema. However, there is little known about the comparative performance of these three techniques. This study was therefore designed to evaluate the effectiveness of the three techniques. Our findings showed that the performance of Chromameter and Mexameter for measurement of UVB-induced erythema was very similar, while FLPI indicated acute erythema at D1 with the greatest fold change. Further studies of UVB dose-dependence need to be carried out.

Donor TLR9 gene tagSNPs influence susceptibility to aGVHD and CMV reactivation in the allo-HSCT setting without polymorphisms in the TLR4 and NOD2 genes.

Owing to ethnicity of the population, those best confirmed polymorphisms in the TLR (toll-like receptor)4 and NOD2 genes with significantly prognostic impact on allogeneic hematopoietic SCT (allo-HSCT) seem to be more applicable to Europeans and are nonpolymorphic in the Asian population. The influence of innate immunity gene polymorphisms on the outcomes of allo-HSCT in those populations has been questioned. We evaluated the influence of 10 candidate single nucleotide polymorphisms (SNPs) in the TLR1, TLR2, TLR3, TLR8 and TLR9 genes on the outcomes of allo-HSCT in a Chinese population including 138 pairs of patients and unrelated donors and a second cohort of 102 pairs of patients and HLA-identical sibling donors. We found that two tagSNPs in the TLR9 gene in the donor side, +1174 A/G (rs352139) and +1635 C/T (rs352140), influenced the risk of acute GVHD (aGVHD) and CMV reactivation. Furthermore, the presence of the susceptible haplotype (A-C) in donor may be an informative predicator of worse OS at 5 years compared with those with the G-C and G-T haplotypes (58% vs 82.9%, P=0.024). Our data suggested an unrecognized association between donor TLR9 tagSNPs and the risk of HSCT-related complications in a population without polymorphisms in the TLR4 and NOD2 genes.

Development of a consumer product ingredient database for chemical exposure screening and prioritization.

Consumer products are a primary source of chemical exposures, yet little structured information is available on the chemical ingredients of these products and the concentrations at which ingredients are present. To address this data gap, we created a database of chemicals in consumer products using product Material Safety Data Sheets (MSDSs) publicly provided by a large retailer. The resulting database represents 1797 unique chemicals mapped to 8921 consumer products and a hierarchy of 353 consumer product "use categories" within a total of 15 top-level categories. We examine the utility of this database and discuss ways in which it will support (i) exposure screening and prioritization, (ii) generic or framework formulations for several indoor/consumer product exposure modeling initiatives, (iii) candidate chemical selection for monitoring near field exposure from proximal sources, and (iv) as activity tracers or ubiquitous exposure sources using "chemical space" map analyses. Chemicals present at high concentrations and across multiple consumer products and use categories that hold high exposure potential are identified. Our database is publicly available to serve regulators, retailers, manufacturers, and the public for predictive screening of chemicals in new and existing consumer products on the basis of exposure and risk.

Adjuvant hepatic intra-arterial iodine-131-lipiodol following curative resection of hepatocellular carcinoma: a prospective randomized trial.

BACKGROUND: The purpose of the present study was to determine whether intrahepatic injection of (131)I-lipiodol (Lipiodol) is effective against recurrence of surgically resected hepatocellular carcinoma (HCC). METHODS: From June 2001 through March 2007, this nationwide multi-center prospective randomized controlled trial enrolled 103 patients 4-6 weeks after curative resection of HCC with complete recovery (52: Lipiodol, 51: Control). Follow-up was every 3 months for 1 year, then every 6 months. Primary and secondary endpoints were recurrence-free survival (RFS) and overall survival (OS), respectively, both of which were evaluated by the Kaplan-Meier technique and summarized by the hazard ratio (HR). The design was based on information obtained from a similar trial that had been conducted in Hong Kong. RESULTS: The Lipiodol group showed a small, and nonsignificant, improvement over control in RFS (HR = 0.75; 95 % confidence interval [95 % CI] 0.46-1.23; p = 0.25) and OS (HR = 0.88; 95 % CI 0.51-1.51; p = 0.64). Only two serious adverse events were reported, both with hypothyroidism caused by (131)I-lipiodol and hepatic artery dissection during angiography. CONCLUSIONS: The randomized trial provides insufficient evidence to recommend the routine use of (131)I-lipiodol in these patients.

Pretransplant Model for End-stage Liver Disease score has no impact on posttransplant survival in living donor liver transplantation.

BACKGROUND: A high Model For End-stage Liver Disease (MELD) score≥25 has been reported to be associated with increased posttransplant mortality and morbidity among patients undergoing living donor liver transplantation (LDLT). We reviewed the results of patients undergoing LDLT at our transplant center for decompensated cirrhosis to determine whether a high MELD impacted posttransplant survival. METHODS: From April 2002 to May 2011, 86-176 patients (49%) who underwent LDLT at our center had the indication of decompensated cirrhosis without hepatocellular carcinoma. Data were expressed in mean values±standard error of the means (range). Patients survival rates were analyzed using Kaplan-Meier method. RESULTS: Among the 86 patients with decompensated cirrhosis: Age was 49±2 (1-68) years and 60 (70%) were of male gender. The causes in 25 (29%) were hepatitis B and 25 (29%) hepatitis C as well as one each for hepatitis B/C and B/D coinfections: 9 (10%), alcoholic cirrhosis. MELD score was 18±1 (range=6-40). In hospital mortality was 6/86 (7%). At 1152±95 (range=7-3317) days posttransplant follow-up 64 (74%) were alive with 1-, 3-, and 5-year survival rates of 84%, 70%, and 70%, respectively. MELD scores did not differ between those who survived and those who died (17.5±8.0 versus 17.8±8.4). No difference was noted in those with MELD<25 or ≥25. In fact, the recipient with the highest MELD score (40) survived. CONCLUSION: A high MELD score had no impact on posttransplant survival among cirrhotic patients undergoing LDLT. It should be considered to be an urgent indication rather than a contraindication to LDLT.

Younger age and presence of macrovascular invasion were independent significant factors associated with poor disease-free survival in hepatocellular carcinoma patients undergoing living donor liver transplantation.

OBJECTIVE: Patients with hepatocellular carcinoma (HCC) exceeding the University of California, San Francisco (UCSF) criteria are normally rejected for cadaveric liver transplants. However, whether they should be allowed to undergo living donor liver transplantation (LDLT) has been controversial. We reviewed the outcome of patients with advanced HCC who underwent LDLT at our center. METHODS: From April 2002 to May 2011, 176 patients underwent LDLT at our center; of these, 77 (44%) had HCC at the explant liver. Patient overall survival and recurrence-free survival (RFS) was analyzed using Kaplan-Meier method. Multivariate analysis was performed by Cox analysis. RESULTS: Age was 56±1 (56, 29-71) years; 62 (80.5%) were male; Model for End-stage Liver Disease Score was 11±1 (9, 6-36), alpha fetoprotein (AFP) was 3683±2019 (69, 3-139,591) ng/L; maximum tumor size was 4.5 (0.5-15) cm. Number or tumor nodules was 5 (1-10), and 32 (42%) had macrovascular invasion diagnosed pretransplant. Eleven (14%) were within UCSF criteria. After follow-up of 953±90 (744, 2-2989) days, 53 (69%) were alive and 48 (62%) were recurrence-free. One-, 3- and 5-year overall survival (OS) and recurrence-free survival (RFS) were 80%, 70%, and 57% and 80%, 65%, and 48%, respectively. Five-year OS and RFS for those within UCSF criteria were both 78% versus 55% and 46% outside UCSF criteria (P=not significant). At multivariate analysis, high AFP, younger age, and macrovascular invasion were associated with both poor RFS. CONCLUSION: In HCC patients exceeding UCSF criteria, a reasonable 5-year overall survival of 55% post-LDLT can be obtained. Patients with HCC exceeding the UCSF criteria, especially in the older age group with no portal vein invasion and lower AFP level, should be actively considered for LDLT.

Twin pregnancy and childbirth after reduced-intensity conditioning allogeneic haematopoietic stem cell transplantation combined with imatinib mesylate for chronic myeloid leukaemia: case report and literature review.

The successful outcome of a pregnancy in a woman who had received reduced-intensity conditioning (RIC) allogeneic haematopoietic stem cell transplantation (allo-HSCT) for chronic myeloid leukaemia is reported; publications on recovery of ovarian function and pregnancy following myeloablative conditioning (MAC) or RIC allo-HSCT for haematological disorders are reviewed. Research suggests that RIC allo-HSCT may facilitate ovarian recovery. Indeed, in the case study presented, the patient had a successful twin pregnancy and delivery, subsequent to treatment. After a 5-year follow-up, the patient survives disease-free with a sustained molecular response; her children are both healthy, with no physical defects. These findings suggest that RIC allo-HSCT combined with short-term imatinib mesylate does not necessarily have profound effects on female fertility.

Haploidentical allogeneic haematopoietic stem cell transplantation as salvage therapy for engraftment failure after unrelated and autologous stem cell transplantation: a case report and review of the literature.

Engraftment failure is a rare but life-threatening complication of haematopoietic stem cell transplantation (HSCT) and treatment of this condition is often challenging. This case report describes a patient with acute myeloid leukaemia and engraftment failure after unrelated donor allogeneic stem cell transplantation. Rescue treatment with granulocyte-colony stimulating factor and reinfusion of autologous 'back-up' stem cells failed, but transplantation of haploidentical donor stem cells following a fludarabine and antithymocyte globulin (ATG)-based conditioning regimen resulted in haematological reconstitution and long-term disease-free survival. The use of haploidentical donor stem cell transplantation as salvage therapy after engraftment failure in adult patients has not, to the authors' knowledge, been previously reported. Additionally, a review of the relevant literature is presented. This case report and literature review suggest that reinfusion of cryopreserved 'back-up' haematopoietic stem cells is a safe and effective salvage therapy for engraftment failure after allogeneic HSCT. Haploidentical donor stem cell transplantation after a fludarabine and ATG-based conditioning regimen could provide effective second-line therapy in adult patients.

Combined heart-liver transplantation with extended cardiopulmonary bypass.

We report a case of combined heart and liver transplantation for familial amyloid polyneuropathy. This is the first such combined transplant performed in Asia, and differs from previously described cases, in that cardiopulmonary bypass was continued at partial flow during liver transplantation in our case. This was done in order to provide haemodynamic support to the cardiac graft and to protect it from the impending reperfusion insult that frequently accompanies liver transplantation. The utility of this management course is discussed, along with its actual and potential complications. We also describe the impact of a lung-protective ventilation strategy employed during cardiac transplantation.

Relationship between TNFA, TNFB and TNFRII gene polymorphisms and outcome after unrelated hematopoietic cell transplantation in a Chinese population.

This study aimed to analyze the association between cytokine gene polymorphisms and outcome following allogeneic hematopoietic SCT (allo-HSCT). A total of 138 unrelated donor/recipient pairs who underwent allo-HSCT from 2001 to 2009 were tested for TNFA-1031 (T>C), -863 (C>A), -857 (C>T), -238 (G>A), TNFB+252 (A>G) and TNFRII codon 196 (T>G) single nucleotide polymorphisms by multiplex SnaPshot analysis. Transplantation involving recipients and/or donors with TNFA-857 C/C genotype or TNFB+252 G allele-positivity resulted in a higher incidence of acute GVHD (aGVHD), which was independent of HLA mismatching. In multivariate analysis, TNFA-857 C/C genotype donors (relative risk (RR)=2.29, P=0.006) and TNFB+252 G allele-positive recipients (RR=1.789, P=0.036) were found to be significantly associated with an increased incidence of aGVHD. TNFA-857 C/C genotype donors (RR=3.748, P=0.002) and TNFB+252 G allele-positive recipients (RR=1.823, P=0.063) were also associated with the development of grades II-IV aGVHD. TNFRII polymorphism in recipients was also related to relapse rate, but no significant associations were found between TNFA, TNFB or TNFRII 196 genotype and cGVHD, relapse or overall survival after transplantation. These results provide the first report of an association between TNFA, TNFB and TNFRII polymorphic features and outcome of allo-HSCT in a Chinese population, and suggest an interaction between TNFA-857 and TNFB+252 genotypes and risk of aGVHD.

The beneficial impact of missing KIR ligands and absence of donor KIR2DS3 gene on outcome following unrelated hematopoietic SCT for myeloid leukemia in the Chinese population.

The effect of natural killer (NK) cell alloreactivity on the outcome of unrelated hematopoietic SCT (HSCT) remains a topic of debate. NK cell alloreactivity after allogeneic HSCT is regulated by killer-cell Ig-like receptors (KIRs). To investigate the influence of KIRs on outcome after unrelated HSCT, we retrospectively analyzed the HLA and KIR genotypes of 116 donor-recipient pairs. We found that missing KIR ligands in recipients were significantly associated with a decreased leukemic relapse risk (P=0.019, HR=0.329), mainly in myeloid disease (P=0.003, HR=0.193). This beneficial effect was seen in AML/myelodysplastic syndrome and also in chronic myeloid leukemia. In myeloid disease, missing KIR ligands also improved 5-year OS (P=0.034, HR=0.430) and disease-free survival (DFS) (P=0.024, HR=0.445). Meanwhile, the presence of donor-activating KIR2DS3 gene was associated with increased relapse risk (P=0.003, HR=5.046), decreased OS (P=0.004, HR=3.181) and DFS (P=0.003, HR=2.919) in myeloid disease. No effect was seen in patients with lymphoid disease. Our study indicated that, in unrelated HSCT for myeloid leukemia, missing KIR ligands in recipients offered a lower relapse risk and a long-term survival advantage. The presence of KIR2DS3 in the donor was an important risk factor for myeloid leukemia.

Distribution of killer-cell immunoglobulin-like receptor genes in Eastern mainland Chinese Han and Taiwanese Han populations.

The interaction between killer-cell immunoglobulin-like receptors (KIRs) and human leukocyte antigen (HLA) molecules expressed on target cells is known to modulate the cytolytic activity of natural killer (NK) cells. To date, a wide range of KIR genotypes has been observed, which varies among different ethnic populations. We report here comparison of the KIR gene content and genotypic structure of KIRs in 106 individuals from Eastern mainland Chinese Han and 97 from Taiwanese Han. All 17 KIR genes were observed in the two populations. Framework genes 2DL4, 3DL2, 3DL3 and 3DP1 were present in all individuals. The two populations had very similar frequencies in most loci, however, significant differences were noted in the frequencies of KIR3DS1 and KIR2DS4D (KIR2DS4 deletant variant). A total of 35 and 29 genotypes were identified in the individuals from the Eastern mainland Chinese and the Taiwanese Hans, respectively. Some pairs of KIRs showed significant positive and negative linkage disequilibrium (LD). Our data showed that there were minor distinctions in KIR gene frequencies, genotypes and LD between the two populations, which shed light on a possible geographic genetic demarcation among different Chinese communities.

Assessment of survival advantage in ampullary carcinoma in relation to tumour biology and morphology.

INTRODUCTION: Carcinoma of the ampulla of Vater is said to carry a significantly better prognosis than pancreatic ductal adenocarcinomas arising in the pancreatic head. However, it is uncertain as to whether this is due to the fact that they have differing oncological characteristics or simply an earlier presentation as a result of the exophytic morphology of ampullary lesions causing obstruction of the bile ducts. METHODS: All patients undergoing pancreaticoduodenectomy between January 1998 and December 2004 were identified from a prospectively maintained database. Patients with a pathologically confirmed ampullary (AMP) tumour were compared to those with a carcinoma of the head of the pancreas (HOP). Tumour characteristics including size, stage and degree of differentiation were analysed as were survival data. RESULTS: 71 AMP and 144 HOP tumours were resected during the period studied and had full histology reports available for assessment. The median diameter of the AMP tumours was significantly less than those of the HOP (2 cm vs. 3 cm; p = 0.04). The T stage distribution differed significantly between the AMP and HOP tumours in favour of the former (Stages I--10 vs. 0 (p = 0.03); II--29 vs. 13 (p = 0.04); III--25 vs. 121 (p = 0.01); IV--7 vs. 10). The number of resection specimens with positive lymph nodes was lower in the AMP group (31 vs. 121; p = 0.03) as was the prevalence of vascular invasion (33 vs. 114; p = 0.006) and neural invasion (23 vs. 134; p = 0.009). There was no difference in the degree of differentiation of the AMP and HOP tumours. The 5-year survival rates were significantly better in the AMP group at 60% vs. 20% (p = 0.008). Subdivision of AMP carcinoma into polypoid (60%) and ulcerating (40%) lesions revealed a non-significant survival advantage in favour of polypoid tumours at (64% vs. 60%; p = 0.07) at 5 years. CONCLUSIONS: The outcome of resection for AMP is significantly better than for pancreatic ductal adenocarcinomas arising in the periampullary region. Although the anatomical position of AMP tumours may contribute to this survival advantage, the HOP tumours exhibit more adverse histological features suggesting that they are different diseases and hence the difference in survival.

Surgery for the palliation of intestinal obstruction in advanced abdominal malignancy.

INTRODUCTION: Intestinal obstruction commonly occurs in advanced abdominal and pelvic malignancy. Management of these patients is difficult, as it is uncertain which patients benefit from palliative surgery and which benefit from medical management. METHODS: Clinical records for patients who underwent surgery for palliation of bowel obstruction were reviewed retrospectively. All had metastatic malignant disease and were seen by the general surgical department for intestinal obstruction. The following factors were examined: preoperative albumin, APACHE II score, age, site of metastases, presence of ascites, operative findings and type of operative procedure performed, length of postoperative stay and mortality. RESULTS: 27 palliative operations for intestinal obstruction for metastatic malignancy were performed during this period. This included two patients who were re-operated on for recurrence of intestinal obstruction after recovering from the first operation. All patients had radiological evidence of intestinal obstruction preoperatively. All patients who survived were discharged from hospital without requiring parenteral nutrition or hydration, and were able to tolerate oral medication and feeds. In this small series, site of metastases, presence of ascites, APACHE II score and gender were not predictive of mortality. An albumin level of 21 g/L or less was predictive of mortality. Almost 50 percent of these patients would require a stoma. Our series had a 30-day mortality rate of 20 percent. CONCLUSION: Surgery does have a role in palliation of symptoms of intestinal obstruction in carefully selected patients with advanced abdominal and pelvic malignancy. Patients should be counselled on the likelihood of a stoma and the 30-day mortality risk.