[Clinical analysis of 86 cases of acute fatty liver of pregnancy]

Objective: To investigate the clinical characteristics and maternal and fetal prognosis of pregnant women with acute fatty liver of pregnancy (AFLP). Methods: The clinical data of 86 AFLP pregnant women admitted to the Third Affiliated Hospital of Guangzhou Medical University from September 2017 to August 2022 were collected, and their general data, clinical characteristics, laboratory tests and maternal and fetal outcomes were retrospectively analyzed. Results: (1) General information: the age of the 86 pregnant women with AFLP was (30.8±5.4) years, and the body mass index was (21.0±2.5) kg/m2. There were 50 primiparas (58.1%, 50/86) and 36 multiparas (41.9%, 36/86). There were 64 singleton pregnancies (74.4%, 64/86) and 22 twin pregnancies (25.6%, 22/86). (2) Clinical characteristics: the main complaints of AFLP pregnant women were gastrointestinal symptoms, including epigastric pain (68.6%, 59/86), nausea (47.7%, 41/86), anorexia (46.5%, 40/86), vomiting (39.5%, 34/86). The main non-gastrointestinal symptoms were jaundice of skin and/or scleral (54.7%, 47/86), edema (38.4%, 33/86), fatigue (19.8%, 17/86), bleeding tendency (16.3%, 14/86), polydipsia or polyuria (14.0%, 12/86), skin itching (8.1%, 7/86), and 17.4% (15/86) AFLP pregnant women had no obvious symptoms. (3) Laboratory tests: the incidence of liver and kidney dysfunction and abnormal coagulation function in AFLP pregnant women was high, and the levels of blood ammonia, lactate dehydrogenase and lactic acid were increased, and the levels of hemoglobin, platelet and albumin decreased. However, only 24 cases (27.9%, 24/86) of AFLP pregnant women showed fatty liver by imageology examination. (4) Pregnancy outcomes: ① AFLP pregnant women had a high incidence of pregnancy complications, mainly including renal insufficiency (95.3%, 82/86), preterm birth (46.5%, 40/86), hypertensive disorders in pregnancy (30.2%, 26/86), gestational diabetes mellitus (36.0%, 31/86), fetal distress (24.4%, 21/86), pulmonary infection (23.3%, 20/86), disseminated intravascular coagulation (16.3%, 14/86), multiple organ dysfunction syndrome (16.3%, 14/86), hepatic encephalopathy (9.3%, 8/86), and intrauterine fetal death (2.3%, 2/86). ② Treatment and outcome of AFLP pregnant women: the intensive care unit transfer rate of AFLP pregnant women was 66.3% (57/86). 82 cases were improved and discharged after treatment, 2 cases were transferred to other hospitals for follow-up treatment, and 2 cases (2.3%, 2/86) died. ③ Neonatal outcomes: except for 2 cases of intrauterine death, a total of 106 neonates were delivered, including 39 cases (36.8%, 39/106) of neonatal asphyxia, 63 cases (59.4%, 63/106) of neonatal intensive care unit admission, and 3 cases (2.8%, 3/106) of neonatal death. Conclusions: AFLP is a severe obstetric complication, which is harmful to mother and fetus. In the process of clinical diagnosis and treatment, attention should be paid to the clinical manifestations and laboratory tests of pregnant women, early diagnosis and active treatment, so as to improve maternal and fetal outcomes.

A neotropical perspective on the uniqueness of the Holocene among interglacials

Understanding how tropical systems have responded to large-scale climate change, such as glacial-interglacial oscillations, and how human impacts have altered those responses is key to current and future ecology. A sedimentary record recovered from Lake Junín, in the Peruvian Andes (4085 m elevation) spans the last 670,000 years and represents the longest continuous and empirically-dated record of tropical vegetation change to date. Spanning seven glacial-interglacial oscillations, fossil pollen and charcoal recovered from the core showed the general dominance of grasslands, although during the warmest times some Andean forest trees grew above their modern limits near the lake. Fire was very rare until the last 12,000 years, when humans were in the landscape. Here we show that, due to human activity, our present interglacial, the Holocene, has a distinctive vegetation composition and ecological trajectory compared with six previous interglacials. Our data reinforce the view that modern vegetation assemblages of high Andean grasslands and the presence of a defined tree line are aspects of a human-modified landscape.

[To compare the efficacy and incidence of severe hematological adverse events of flumatinib and imatinib in patients newly diagnosed with chronic phase chronic myeloid leukemia]

Objective: To analyze and compare therapy responses, outcomes, and incidence of severe hematologic adverse events of flumatinib and imatinib in patients newly diagnosed with chronic phase chronic myeloid leukemia (CML) . Methods: Data of patients with chronic phase CML diagnosed between January 2006 and November 2022 from 76 centers, aged ≥18 years, and received initial flumatinib or imatinib therapy within 6 months after diagnosis in China were retrospectively interrogated. Propensity score matching (PSM) analysis was performed to reduce the bias of the initial TKI selection, and the therapy responses and outcomes of patients receiving initial flumatinib or imatinib therapy were compared. Results: A total of 4 833 adult patients with CML receiving initial imatinib (n=4 380) or flumatinib (n=453) therapy were included in the study. In the imatinib cohort, the median follow-up time was 54 [interquartile range (IQR), 31-85] months, and the 7-year cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) were 95.2%, 88.4%, 78.3%, and 63.0%, respectively. The 7-year FFS, PFS, and OS rates were 71.8%, 93.0%, and 96.9%, respectively. With the median follow-up of 18 (IQR, 13-25) months in the flumatinib cohort, the 2-year cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) were 95.4%, 86.5%, 58.4%, and 46.6%, respectively. The 2-year FFS, PFS, and OS rates were 80.1%, 95.0%, and 99.5%, respectively. The PSM analysis indicated that patients receiving initial flumatinib therapy had significantly higher cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) and higher probabilities of FFS than those receiving the initial imatinib therapy (all P<0.001), whereas the PFS (P=0.230) and OS (P=0.268) were comparable between the two cohorts. The incidence of severe hematologic adverse events (grade≥Ⅲ) was comparable in the two cohorts. Conclusion: Patients receiving initial flumatinib therapy had higher cumulative incidences of therapy responses and higher probability of FFS than those receiving initial imatinib therapy, whereas the incidence of severe hematologic adverse events was comparable between the two cohorts.

[Clinical presentation and prognosis in children over 10-year-old with primary nephrotic syndrome]

Objective: To summary the clinical presentation and prognosis of primary nephrotic syndrome (PNS) in teenagers. Methods: The clinical data, renal pathological types and prognosis of 118 children over 10-year-old with PNS treated in the Department of Nephrology of the Children's Hospital Affiliated to Capital Institute of Pediatrics from January 2010 to December 2020 were retrospectively analyzed, with 408 children ≤10-year-old as control group synchronously. Chi-square test was used to compare the difference of clinical types, pathologic types, response to steroids and tubulointerstitial changes between the groups. The teenagers with steroid resistant nephrotic syndrome (SRNS) were divided into initial non-responder group and late non-responder group. Kaplan-Meier method was used to compare the difference of persistent proteinuria, and Fisher's exact test for the histological types. Results: There were 118 children >10-year-old, including 74 males and 44 females, with the onset age of 12.1 (10.8, 13.4) years; and 408 children ≤10-year-old with the onset age of 4.5 (3.2, 6.8) years. The proportion of SRNS was significantly higher in patients >10-year-old than those ≤10-year-old (24.6% (29/118) vs. 15.9% (65/408), χ²=4.66, P=0.031). There was no statistical difference in the pathological types between >10-year-old and ≤10-year-old (P>0.05), with minimal change disease the most common type (56.0% (14/25) vs. 60.5% (26/43)). The percentage of cases with renal tubulointerstitial lesions was significantly higher in children >10-year-old compared to those ≤10-year-old (60.0% (15/25) vs. 23.3% (10/43), χ²=9.18, P=0.002). There were 29 cases presented with SRNS in PNS over 10-year-old, including 19 initial non-responders and 10 late non-responders. Analyzed by Kaplan-Meier curve, it was shown that the percentage of persistent proteinuria after 6 months of immunosuppressive treatments was significantly higher in initial non-responders than those of the late non-responders ((22±10)% vs. 0, χ²=14.68, P<0.001); the percentage of minimal change disease was significantly higher in patients of late non-responders than those of the initial non-responders (5/6 vs. 3/13, P=0.041). Of the 63 >10-year-old with steroid-sensitive nephrotic syndrome followed up more than one year, 38 cases (60.3%) had relapse, and 14 cases (22.2%) were frequent relapse nephrotic syndrome and steroid dependent nephrotic syndrome. Among the 45 patients followed up over 18-year-old, 22 cases (48.9%) had recurrent proteinuria continued to adulthood, 3 cases of SRNS progressed to kidney insufficiency, and one of them developed into end stage kidney disease and was administrated with hemodialysis. Conclusions: Cases over 10-year-old with PNS tend to present with SRNS and renal tubulointerstitial lesions. They have a favorable prognosis, but are liable to relapse in adulthood.

[Clinical and genetic characteristics of young patients with myeloproliferative neoplasms]

Objectives: To investigate the clinical and genetic features of young Chinese patients with myeloproliferative neoplasms (MPN). Methods: In this cross-sectional study, anonymous questionnaires were distributed to patients with MPN patients nationwide. The respondents were divided into 3 groups based on their age at diagnosis: young (≤40 years) , middle-aged (41-60 years) , and elderly (>60 years) . We compared the clinical and genetic characteristics of three groups of MPN patients. Results: 1727 assessable questionnaires were collected. There were 453 (26.2%) young respondents with MPNs, including 274 with essential thrombocythemia (ET) , 80 with polycythemia vera (PV) , and 99 with myelofibrosis. Among the young group, 178 (39.3%) were male, and the median age was 31 (18-40) years. In comparison to middle-aged and elderly respondents, young respondents with MPN were more likely to present with a higher proportion of unmarried status (all P<0.001) , a higher education level (all P<0.001) , less comorbidity (ies) , fewer medications (all P<0.001) , and low-risk stratification (all P<0.001) . Younger respondents experienced headache (ET, P<0.001; PV, P=0.007; MF, P=0.001) at diagnosis, had splenomegaly at diagnosis (PV, P<0.001) , and survey (ET, P=0.052; PV, P=0.063) . Younger respondents had fewer thrombotic events at diagnosis (ET, P<0.001; PV, P=0.011) and during the survey (ET, P<0.001; PV, P=0.003) . JAK2 mutations were found in fewer young people (ET, P<0.001; PV, P<0.001; MF, P=0.013) ; however, CALR mutations were found in more young people (ET, P<0.001; MF, P=0.015) . Furthermore, mutations in non-driver genes (ET, P=0.042; PV, P=0.043; MF, P=0.004) and high-molecular risk mutations (ET, P=0.024; PV, P=0.023; MF, P=0.001) were found in fewer young respondents. Conclusion: Compared with middle-aged and elderly patients, young patients with MPN had unique clinical and genetic characteristics.

Effects of molecular weight fraction on antioxidation capacity of rice protein hydrolysates

Rice protein was used as a starting material to provide rice protein hydrolysates (RPH) through enzyme-assisted extraction. RPH was further fractionated using ultrafiltration membrane (UF) and classified by molecular weight (MW; MW < 1 kDa, MW 1-10 kDa, and MW > 10 kDa). Peptides with MW < 1 kDa possessed superior antioxidant properties (p < 0.05). Therefore, UF demonstrated great efficacy in selectively separating antioxidant peptides. A Pearson correlation analysis revealed that the total phenolic concentration was correlated with oxygen radical absorbance capacity (ORAC; r = 0.999, p < 0.05). Amino acid contents had negative correlations with the scavenging activity (specifically, IC50) of 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radicals (r =  - 0.986 to - 1.000). Reducing power was related to aromatic amino acid contents (r = 0.997, p < 0.05). In this study, enzymatic hydrolysis was discovered to be an effective method of extracting and isolating natural antioxidant proteins from broken rice, thus preserving the nutritional quality of rice and making those proteins more accessible in future applications.

[Effect of P311 microspheres-loaded thermosensitive chitosan hydrogel on the wound healing of full-thickness skin defects in rats]

Objective: To explore the effect of P311 microspheres-loaded thermosensitive chitosan hydrogel on the wound healing of full-thickness skin defects in rats. Methods: The method of experimental study was adopted. The polyvinyl alcohol/sodium alginate microspheres (simple microspheres), P311 microspheres, and bovine serum albumin labeled with fluorescein isothiocyanate (FITC-BSA) microspheres were prepared by water-in-oil emulsification, and then their morphology was observed under a light microscope/inverted fluorescence microscope. Chitosan solution was prepared, chitosan solution and β-glycerol phosphate disodium hydrate were mixed to prepare simple thermosensitive hydrogels, and thermosensitive hydrogels loaded with simple microspheres or P311 microspheres were prepared by adding corresponding substances in simple thermosensitive hydrogels. The morphological changes of the prepared four liquids in the state of tilt was observed at 37 ℃. After being freeze-dried, the micromorphology of the prepared four liquids was observed under a scanning electron microscope. Eighteen 3-4-week-old male Sprague-Dawley rats were divided into normal group without any treatment, dressing group, chitosan group, hydrogel alone group, simple microspheres-loaded hydrogel group, and P311 microspheres-loaded hydrogel group, which were inflicted with one full-thickness skin defect wound on both sides of the back spine and were dealt correspondingly, with 3 rats in each group. Rats with full-thickness skin defects in the five groups were collected, the wound healing was observed on post injury day (PID) 0 (immediately), 5, 10, and 15, and the wound healing rates on PID 5, 10, and 15 were calculated. The wound and wound margin tissue of rats with full-thickness skin defects in the five groups on PID 15 and normal skin tissue in the same site of rats in normal group were collected, hematoxylin and eosin staining was conducted to observe the histological changes, immunohistochemical staining was performed to observe the expressions of CD31 and vascular endothelial growth factor (VEGF), and Western blotting was conducted to detect the protein expressions of CD31 and VEGF. The number of samples was all three. Data were statistically analyzed with one-way analysis of variance, analysis of variance for repeated measurement, and Bonferroni correction. Results: Simple microspheres were spherical, with loose and porous surface. The surfaces of P311 microspheres and FITC-BSA microspheres were smooth without pores, and the FITC-BSA microspheres emitted uniform green fluorescence. The diameters of the three microspheres were basically consistent, being 33.1 to 37.7 μm. Compared with chitosan solution and simple thermosensitive hydrogel, the structures of the two microspheres-loaded hydrogels were more stable in the state of tilt at 37 ℃. The two microspheres-loaded hydrogels had denser network structures than those of chitosan solution and simple thermosensitive hydrogel, and in the cross section of which microspheres with a diameter of about 30 μm could be seen. Within PID 15, the wounds of rats in the five groups were healed to different degrees, and the wound healing of rats in P311 microspheres-loaded hydrogel group was the best. On PID 5, 10, and 15, the wound healing rates of rats in dressing group and chitosan group were (26.6±2.4)%, (38.5±3.1)%, (50.9±1.5)%, (47.6±2.0)%, (58.5±3.6)%, and (66.7±4.1)%, respectively, which were significantly lower than (59.3±4.8)%, (87.6±3.2)%, (97.2±1.0)% in P311 microspheres-loaded hydrogel group (P<0.05 or P<0.01). The wound healing rates of rats in hydrogel alone group on PID 10 and 15, and in simple microspheres-loaded hydrogel group on PID 15 were (76.0±3.3)%, (84.5±3.6)%, and (88.0±2.6)%, respectively, which were significantly lower than those in P311 microspheres-loaded hydrogel group (P<0.05). The epidermis, hair follicles, and sebaceous glands could be seen in the normal skin of rats in normal group, without positive expressions of CD31 or VEGF. The wounds of rats in P311 microspheres-loaded hydrogel group on PID 15 were almost completely epithelialized, with more blood vessels, hair follicles, sebaceous glands, and positive expressions of CD31 and VEGF in the wounds than those of rats with full-thickness skin defects in the other four groups, and more protein expressions of CD31 and VEGF than those of rats in the other five groups. Conclusions: The P311 microspheres-loaded thermosensitive chitosan hydrogel can release the encapsulated drug slowly, prolong the drug action time, and promote wound healing in rats with full-thickness skin defects by promoting wound angiogenesis and re-epithelialization.

Legacy effects of infection in patients with heart failure: a national cohort study of 31,318 patients in Taiwan

Background

Although infection is a common cause of hospitalization in patients (pts) with heart failure (HF), the long-term cardiovascular (CV) prognosis in HF after infection is not well studied.

Methods and results

From 2009 to 2015, 310,485 pts with their first HF admissions and survival to discharge were identified from the National Health Insurance Research Database. Among the pts, 103,505 (33.3%) were readmitted within 1 year after HF discharge for infection, including pneumonia (44.2%), urinary tract infection (UTI) (37.9%), skin and soft tissue infections (9.7%), and others (8.1%). Those without admission for any infection were controls. We compared the primary composite endpoint, including all-cause death, acute myocardial infarction (AMI), stroke, and hospitalization for HF (HHF) between the 2 groups after the infection episode. After propensity score matching, the clinical characteristics (age 71.7±13.9 years, male 52.0%) and treatment were similar between the groups (n=15,659 in each group). In a mean follow-up time of 4.3±2.9 years, 86.2% pts with a history of infection admission and 63.6% pts in the control group met the primary endpoint. Multivariate Cox proportional hazards analysis showed the infection group had a higher risk of the primary composite endpoint (HR 1.760, 95% CI 1.714–1.807), including all-cause death (HR 1.587, 95% CI: 1.540–1.636), HHF (HR 1.993, 95% CI 1.922–2.066), AMI (HR 1.332, 95% CI 1.224–1.450), and stroke (HR 1.769, 95% CI 1.664–1.882). In infection group, HHF was the earliest outcome event with a mean time of 17.5 months and mortality is the second early event with a mean time of 23 months after discharge from the infection episode. Pneumonia carried a higher risk than UTI for the primary composite endpoint (HR 1.140, 95% CI 1.104–1.178).

Conclusions

One-third of HF pts discharged from the hospital experienced acute infection that required readmission. The pts had worse CV prognosis after readmission for infectious disease compared to those without infection

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): This study is supported by National Cheng Kung University Hospital and Tainan Hospital, Ministry of Health and Welfare, Taiwan.

Profiled polyethylene terephthalate filaments that incorporate collagen and calcium phosphate enhance ligamentisation and bone formation

Polyethylene terephthalate (PET) artificial ligaments offer an unlimited source of ligaments without donor-site-related morbidity and with good mechanical properties for a rapid return to sporting activities. Developing PET artificial ligaments with excellent ligamentisation and ligament-bone healing is still a considerable challenge. This study aimed to investigate the effects of the profiled PET/collagen/calcium phosphate (PET/C/CaP) ligament upon cell growth, ligamentisation and ligament-bone healing in vitro and in vivo. Profiled PET/C/CaP filaments were made by melt-spinning process with 2 % CaP hybrid spinning and collagen coating. Rat mesenchymal stem cells (MSCs) were cultured on the profiled PET/C filaments for cytotoxicity, viability, scanning electron microscopy (SEM) and ligament-related gene expression analysis. MSCs' osteogenic capacity on the profiled PET/CaP filaments was identified by detecting osteogenic gene expression and alizarin red S staining. For in vivo verification, an animal study was performed to evaluate the effect of the profiled PET/C/CaP ligament in a rabbit knee medial collateral ligament reinforcement reconstruction model. The graft ligamentisation and bone formation were investigated by SEM, histology, microcomputed tomography and mechanical tests. The profiled PET/C filaments enhanced MSC proliferation and ligament-related gene expression. Furthermore, they enhanced osteogenic gene expression, alkaline phosphatase activity and mineralisation of MSCs. The in vivo study indicated that the profiled PET/C/CaP ligament enhanced ligamentous matrix remodelling and bone formation. Therefore, their use is an effective strategy for promoting MSCs' ligamentous and osteogenic potential in vitro and enhancing ligamentous matrix remodelling and bone formation in vivo.

Thrombosis and major bleeding risk after primary percutaneous coronary intervention among patients with multi-vessels coronary artery disease

Background and aims

The present study aimed to develop and validate separate risk prediction models for thrombosis events (TEs) and major bleeding (MB) in patients with multi-vessel coronary artery lesions who had undergone primary percutaneous coronary intervention (PCI).

Methods and results

TEs were defined as the composite of myocardial infarction recurrence or ischemic cerebrovascular events, whereas MB was defined as the occurrence of bleeding academic research consortium (BARC) 3 or 5 bleeding. The derivation and validation cohorts comprised 2976 patients who underwent primary PCI between January 2010 and June 2017. At a median follow-up of 3.07 years (1122 days), TEs and MB occurred in 167 and 98 patients, respectively. Independent predictors of TEs were older age, prior PCI, non-ST elevated MI (NSTEMI), and stent thrombosis (ST). Independent predictors of MB were triple therapy at discharge, coronary artery bifurcation lesions, lesion restenosis, target lesion of the left main coronary artery, and PTCA. In the derivation and validation cohorts, the areas under the curve were 0.817 and 0.820 for thrombosis and 0.886 and 0.976 for bleeding, respectively. In the derivation cohort, high thrombotic risk (n=755) was associated with a higher 3-year incidence of TEs, major adverse cardiovascular events (MACEs), and all-cause death, compared to low risk (n=1275) (p=0.0022, 0.019, 0.012, respectively). High bleeding risk (n=1675) was associated with a higher incidence of bleeding, MACEs, cardiac death, compared to low risk (n=355) (p&lt;0.0001).

Conclusion

Simple risk scores can be useful in predicting the risks of ischemic and bleeding events after primary PCI, thereby stratifying thrombotic or MB risks and facilitating clinical decisions.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): This study was supported by the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (2016-I2M-1–009), National Natural Science Funds (number: 81970308) and the Fund of “Sanming” Project of Medicine in Shenzhen (number: SZSM201911017). Figure 2Figure 3

Phenotypic and genetic correlations of pork myoglobin content with meat colour and other traits in an eight breed-crossed heterogeneous population

Meat colour is one of the most important meat quality traits affecting consumption desire. Genetic improvement for meat colour traits is not so easy because pigs can be phenotyped only after slaughter. Besides the parameters from the optical instrument, other indexes that reflect the material basis of meat colour should be measured accurately and used in the genomic analysis. Myoglobin (Mb) is the main chemical component determining meat colour. However, to what extent the Mb content contributes to meat colour, and whether it can be used as a trait for pig breeding to improve meat colour, and the correlations of Mb content with complex porcine traits are largely unknown. To address these questions, we measured the muscle Mb content in 624 pigs from the 7th generation of a specially designed eight breed-crossed pig heterogeneous population, evaluated its phenotypic and genetic correlations with longissimus thoracis colour score at 24 h after slaughter. More than that, we also systematically phenotyped more than 100 traits on these animals to evaluate the potential correlations between muscle Mb content and economically important traits. Our results showed that the average muscle Mb content in the 624 pigs was 1.00 mg/g, ranging from 0.51 to 2.17 mg/g. We found that higher Mb content usually correlated with favourable meat colour, higher marbling score, less moisture content, and less drip loss. Genetic correlation analysis between muscle Mb content and 101 traits measured in this study shows that Mb content is also significantly correlated with 31 traits, including marbling, shear force, firmness, and juiciness. To our knowledge, this is one of the largest studies about the correlations of muscle Mb content with as many as 100 various traits in a large-scale genetically diversified population. Our results showed that the Mb content could be a selection parameter for the genetic improvement of meat colour. The selection for higher Mb content will also benefit marbling, shear force, firmness, and overall liking but might not affect the growth, carcass, and fat deposition traits.

Effects of Different Chenopodium formosanum Parts on Antioxidant Capacity and Optimal Extraction Analysis by Taguchi Method

Chenopodium formosanum (CF), rich in nutrients and antioxidants, is a native plant in Taiwan. During the harvest, the seeds are collected, while the roots, stems, and leaves remain on the field as agricultural waste. In this study, di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) radical scavenging ability and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging ability experiments of seeds, leaves, stems, and roots were designed using the Taguchi method (TM) under three conditions: Ethanol concentration (0-100%), temperature (25-65 °C), and extraction time (30-150 min). The result demonstrates that seeds and leaves have higher radical scavenging ability than stems and roots. Many studies focused on CF seeds. Therefore, this study selected CF leaves and optimized DPPH, ABTS, total phenol content (TPC), total flavonoid content (TFC), and reducing power (RP) through TM, showing that the predicted value of the leaf is close to the actual value. The optimized results of CF leaves were DPPH 85.22%, ABTS 46.51%, TPC 116.54 µg GAE/mL, TFC 143.46 µg QE/mL, and RP 23.29 µg VCE (vitamin C equivalent)/mL. The DPPH and ABTS of CF leaves were second only to the results of CF seeds. It can be seen that CF leaves have the potential as a source of antioxidants and help in waste reduction.

Evaluating the Antioxidants, Whitening and Antiaging Properties of Rice Protein Hydrolysates

Plant-derived protein hydrolysates have potential applications in nutrition. Rice protein hydrolysates (RPHs), an excellent source of proteins, have attracted attention for the development of cosmeceuticals. However, few studies have reported the potential application of RPH in analysis, and this study examined their antioxidant activities and the inhibitory activities of skin aging enzymes. The results indicated that the total phenolic and flavonoid concentrations were 2.06 ± 0.13 mg gallic acid equivalent/g RPHs and 25.96 ± 0.52 µg quercetin equivalent/g RPHs, respectively. RPHs demonstrated dose-dependent activity for scavenging free radicals from 1,1-diphenyl-2-picrylhydrazyl [half-maximal inhibitory concentration (IC50) = 42.58 ± 2.1 mg/g RPHs] and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (IC50 = 2.11 ± 0.88 mg/g RPHs), dose-dependent reduction capacity (6.95 ± 1.40 mg vitamin C equivalent/g RPHs) and oxygen radical absorbance capacity (473 µmol Trolox equivalent/g RPHs). The concentrations of the RPH solution required to achieve 50% inhibition of hyaluronidase and tyrosinase activities were determined to be 8.91 and 107.6 mg/mL, respectively. This study demonstrated that RPHs have antioxidant, antihyaluronidase, and antityrosinase activities for future cosmetic applications.

CgPBA1 may be involved in nuclear degradation during secretory cavity formation by programmed cell death in Citrus grandis 'Tomentosa' fruits

Caspase-3 is the crucial executor caspase of apoptosis in mammalian cells, which is essential for chromatin condensation and DNA fragmentation. Although plants have no caspase-3 homologs, PBA1 acts as a plant caspase-3-like enzyme in plant programmed cell death (PCD). PCD occurs during the formation of secretory cavities in Citrus fruits; hence, secretory cavities could be utilized as a new cell biology model for investigating the regulatory mechanisms of plant PCD. To further study the association between PBA1 and PCD during secretory cavity development in Citrus fruits, CgPBA1 was identified in the fruit of Citrus grandis 'Tomentosa'. The temporal and spatial expression of CgPBA1 during secretory cavity development were analyzed using quantitative real-time PCR and in situ hybridization, and the morphological changes in the apoptotic cell nuclei were observed using TUNEL assay and ultra-thin section technology. The results revealed that the full-length cDNA of CgPBA1 contains a 711 bp ORF that encodes a putative protein containing 236 amino acid with a proteasome-β-6 functional domain that belongs to the Ntn hydrolase super family. CgPBA1 was predominantly expressed in the secretory cavities; its expression changes coincided with the morphological changes and DNA fragmentation in apoptotic cell nuclei. The green fluorescent fusion protein of CgPBA1 is also located in the nucleus of tobacco epidermal cells. Based on previous research and the findings of the present study, we speculate that CgPBA1 is a highly functional conserved protein in plants, and it might be involved in nuclear degradation during PCD for secretory cavity formation in C. grandis 'Tomentosa' fruits.

[A new strategy for non-invasive diagnosis of liver diseases: DSA-FACE technology based-glycomics method]

Chronic liver disease has gradually become a serious health problem worldwide. Liver biopsy is the current gold standard to assess liver lesions; however, it is an invasive procedure that may cause severe complications. Therefore, there is an urgent need for an economical and rapid non-invasive detection method that can be used in clinic for diagnosis. In the past decade, protein glycosylation has become a research hotspot, and the concept of changes in serum proteoglycans structure has gradually been accepted by many researchers as an indication of liver injury. At the same time, N-linked glycans via DNA sequencing equipment-Fluorophore Assisted Carbohydrate Electrophoresis (DSA-FACE) has also brought high sensitivity and specificity diagnostic models (GlycoHepatoTest) for various chronic liver diseases, which is a new strategy for non-invasive diagnosis of liver diseases.

[Application of serum N -glycan profiling diagnostic model in evaluation of liver fibrosis in patients with hepatitis C]

Objective: To study the changes of serum N-glycan abundance in patients with liver fibrosis at different stages of hepatitis C, and to establish and evaluate the diagnostic model for clinical application value. Methods: Data of 169 hepatitis C virus-infected cases with liver fibrosis were enrolled. Nine kinds of serum N-glycans were detected and analyzed using DNA sequencer-assisted fluorophore-assisted capillary electrophoresis technology. A binary logistics regression method was used to establish a diagnostic model based on the changes in the relative content of N-glycans in each stage of liver fibrosis. Receiver operating characteristic curve was used to evaluate and compare the diagnostic efficacy with other liver fibrosis diagnostic models. Results: N-glycan diagnostic model (B and C) had highest AUROC= 0.776, 0.827 for distinguishing fibrosis S1~S2 to S3~S4 and S1~S3 to S4 than GlycoFibroTest (AUROC = 0.760, 0.807), GlycoCirrhoTest (AUROC = 0.722, 0.787), aspartate aminotransferase to platelet ratio index (AUROC = 0.755, 0.751), FIB-4 index (AUROC = 0.730, 0.774), and S-index (AUROC = 0.707, 0.744). However, the diagnostic efficacy of model A (AUROC = 0.752) for distinguishing fibrosis S1 with S2~S4 had lower diagnostic potency than that of the aspartate aminotransferase to platelet ratio index (AUROC = 0.807). Diagnostic efficiency was improved when the N-glycan profiling and the aspartate aminotransferase to platelet ratio index were combined to diagnose liver fibrosis in each stage, and the area under the receiver operating characteristic curve was 0.839, 0.825, and 0.837, respectively. Conclusion: The serum N-glycan profiling diagnostic model has potential clinical application value in the diagnosis of liver fibrosis in patients with hepatitis C.

Effects of Storage Time and Temperature on Antioxidants in Juice from Momordica charantia L. and Momordica charantia L. var. abbreviata Ser

This study determined the antioxidant activities of juice from Momordica charantia L. (MC) and MC var. abbreviata Ser. (MCVAS) by analyzing 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability, ferric reducing power (FRP), and total phenolic content (TPC). The effects of storage time and storage temperature on these antioxidant activities were investigated. Liquid chromatography-mass spectrometry was conducted to identify the major components of MC and MCVAS. The results revealed that the antioxidant activity of MCVAS was better than that of MC, possibly because of richer components of MCVAS. For MC and MCVAS, the scavenging concentrations of 50% DPPH were 3.33 and 1.19 mg/mL, respectively; moreover, the FRP values were 68.93 and 118.14 mg ascorbic acid equivalent/g dry weight, respectively; and the TPC values were 8.15 and 11.47 mg gallic acid equivalent/g dry weight, respectively. The antioxidant activities of MC and MCVAS decreased with storage time. High storage temperature decreased antioxidant activity more quickly than a low temperature. In addition, MC had exhibited a faster decline in DPPH scavenging ability and FRP than MCVAS during 24-day storage, but no difference was observed in TPC.

Colistin and tylosin enhances disaccharidase activities, and improves morphology and permeability of the intestine of broilers

1. The present study focused on the potential effects of antibiotics on intestinal digestion and integrity in broilers in terms of disaccharidase activity, electrophysiological properties and morphology. 2. One-day-old Arbour Acres birds were randomly allocated to one of four treatment groups for 42 days; control, colistin (20 mg/kg), tylosin (55 mg/kg) or chlortetracycline (CTC, 55 mg/kg) groups. Colistin and tylosin supplementation, but not CTC supplementation, caused an increase in body weight gain. 3. Colistin and tylosin elevated the activities of maltase and sucrase in the mucosa of the jejunum on d 42. Age caused a gradual decrease in the short-circuit current (Isc) and conductance (Gt) of the ileum, as a measure of permeability. The Isc and Gt of the ileum were higher in the colistin-supplemented broilers than in the control birds on d 42. Tylosin- and CTC-supplemented birds displayed Isc and Gt values similar to those of the control birds. 4. Colistin supplementation increased the villus area in the jejunum and thinned the muscularis mucosae in the ileum compared with the control group. Tylosin supplementation decreased the thickness of the muscularis mucosae and the depth of crypt in the jejunum. CTC thickened the muscularis mucosae in the jejunum and ileum. 5. Colistin and tylosin exhibited a beneficial effect on intestinal digestion and integrity by enhancing disaccharidase activities and improving gut morphology and permeability.

Hybridization Dynamics in CeCoIn_{5} Revealed by Ultrafast Optical Spectroscopy

We investigate the quasiparticle dynamics in the prototypical heavy fermion CeCoIn_{5} using ultrafast optical pump-probe spectroscopy. Our results indicate that this material system undergoes hybridization fluctuations before the establishment of heavy electron coherence, as the temperature decreases from ∼120  K (T^{†}) to ∼55  K (T^{*}). We reveal that the anomalous coherent phonon softening and damping reduction below T^{*} are directly associated with the emergence of collective hybridization. We also discover a distinct collective mode with an energy of ∼8  meV, which may be experimental evidence of the predicted unconventional density wave. Our findings provide important information for understanding the hybridization dynamics in heavy fermion systems.

264The long noncoding RNA H19 modulates cardiac remodeling after infarction

Noncoding RNAs account for 80% of human transcripts, but functional studies on noncoding RNAs are relatively few and limited. Long noncoding RNAs (lncRNAs) are known to have an important role in cardiac development, and lately, high-throughput RNA sequencing has been extensively utilized to profile and explore the transcriptome landscape of lncRNAs in failing hearts. These studies have revealed that lncRNAs are mostly dysregulated in failing hearts and their expression signature can discriminate failing hearts of different etiologies.

H19 is abundantly expressed in failing human hearts and its polymorphism was shown to possess a significant correlation with the risk of coronary artery diseases. In our study using murine hearts, we discovered that H19 was significantly up regulated in the heart after ischemic injury, with predominant expression in cardiac fibroblasts. This finding piqued our interest to further investigate the function of H19 in the heart.

We demonstrated that ectopic overexpression of H19 using the AAV approach led to severe cardiac fibrosis in mouse hearts following myocardial infarction. In light of this finding, we generated H19 knockout mice to further investigate the functionality of H19 and we found that cardiac fibrosis was attenuated in these mice. Altogether, these findings suggested that H19 is a fibrosis regulator during cardiac remodeling process after infarction. Due to the multiple regulatory roles of lncRNAs, we then took advantage of chromatin isolation by RNA purification (ChIRP) to identify the H19-interacting protein, YB-1. Surprisingly, mice with YB-1 knockdown displayed severe cardiac fibrosis even without injury. Furthermore, we demonstrated that YB-1 is a transcriptional suppressor of collagen 1A1. Knockout of H19 in YB-1 knockdown partially suppressed Col1a1 expression, which suggests a negative regulatory role of H19 on YB-1 towards the expression of Col1a1.

Taking into account all of these findings, we concluded that H19 mediates collagen expression in fibroblasts through the inhibition of YB-1 activity during cardiac remodeling.

P1604Validating previously reported Brugada syndrome-associated common variants identified in caucasian population in the Han Chinese BrS cohort in Taiwan: SADS-BrS registry

Background

Brugada syndrome (BrS) is a sudden arrhythmic death. The prevalence of BrS is higher in the Southeast Asian populations than that in Caucasian patients. A previous genome-wide association study (GWAS) has reported 13 SNPs significantly associated with BrS. However, no study was performed to validate whether these SNPs are enriched in BrS patients in Han Chinese (HC).

Purpose

Evaluating the common variants previously reported in Caucasian BrS patients could be generalized to HC BrS patients in Taiwan

Methods

We genotyped 200 unrelated BrS patients using Affymetrix TWB Array (N=653,291 SNPs, a customized array for HC in Taiwan). The controls are obtained from the Taiwan Biobank (N ≈ 16,000) using the same array. An imputation workflow was shown in Figure 1. To confirm the accuracy of the imputed genotype of each variant, Sanger sequencing was performed in 10% of randomly selected cases.

Results

Among the 3 most important common variants (rs11708996 in SCN5A, rs10428132 in SCN10A and rs9388451 in HEY2/NCOA7) reported in the previous GWAS mainly conducted in Caucasian BrS patients, 2 of them (rs10428132 and rs9388451) were successfully replicated in the HC population in Taiwan (P<0.01). We also found that the differences of minor allele frequency (dMAF: the MAF of cases minus the MAF of controls) of the two variants were relatively smaller between the BrS cases and healthy controls in HC population compared with that in Caucasian populations (dMAF, rs9388451: 0.15 (Caucasian) vs −0.07 (HC); rs10428132: 0.28 (Caucasian) vs 0.11 (HC)). For the remaining 10 common variants reaching genome-wide significance (P=5×10–8) in Caucasian BrS patients, 9 of them were also significantly enriched in the HC BrS patients after the Bonferroni correction (P<0.05/12=0.0042). We next analyzed the variants identified in the previous GWAS on ECG traits (PR interval, QRS duration, QTc interval, and heart rate) in the Caucasian population. Among the reported 75 variants associated with ECG traits, 5 common variants (rs6798015 (PR), rs1760876 (QRS), rs6795970 (PR/QRS), rs2074238 (QTc) and rs314370 (heart rate)) were significant after Bonferroni correction (P<0.05/75=0.00066).

Figure 1

Conclusions

The preliminary results indicated that 85% of common variants of SCN10A and HEY2/NCOA7 previously reported in Caucasian BrS patients are replicated in BrS patients in the HC population but not the common variant of SCN5A (rs11708996). Furthermore, the common variants of SCN10A and HEY2/NCOA7 related to cardiac depolarization or repolarization may also contribute to the development of BrS.

Acknowledgement/Funding

NTUH 106-S3469, NTUH106-S3458 and NTUH 106-018

[Impact of oxidative stress on renal dopamine D(1) receptor dysfunction in offspring of diabetic rat dams]

Objective: To explore the effects of oxidative stress on renal dopamine D(1) receptor dysfunction in offspring of diabetic rat dams. Methods: The pregnant Sprague Dawley (SD) rats (n=10) were randomly divided into the diabetic group (a single intraperitoneal injection of 35 mg/kg streptozotocin on day 0 of gestation) and control group (injected with the equal volume of 0.9% saline on day 0 of gestation) according to the random number table (n=5 each group). The offspring rats were divided into 4 groups including offspring of control dams treated with vehicle, offspring of control dams treated with antioxidant, offspring of diabetic dams treated with vehicle and offspring of diabetic dams treated with antioxidant (n=10 each group). After birth, the offspring rats were treated with normal drinking water or antioxidant (tempol, 1.0 mmol/L) from the age of 4 weeks until the end of the study (20 weeks). The blood pressure was monitored continuously by non-invasive tail-cuff method. The renal oxidative markers including superoxide dismutase (SOD) and malondialdehyde (MDA) activity and D(1) receptor agonist (fenoldopam)-mediated urinary and sodium excretion were detected. Furthermore, the protein expression of renal G protein-coupled receptor kinase 2 (GRK2), GRK4, dopamine D(1) receptor and the phosphorylation level of D(1) receptor were detected. Results: The mean arterial pressure of offspring from the diabetic dams treated with vehicle was significantly higher than that of offspring from control dams treated with vehicle (P=0.013), while the mean arterial pressure of offspring from diabetic dams treated with antioxidant was significantly lower than that of offspring from the diabetic dams treated with vehicle (P=0.038). The fenoldopam-mediated urinary flow and urinary sodium excretion rate were significantly lower in offspring of diabetic dams treated with vehicle than those in offspring of control dams treated with vehicle (P<0.01), which were significantly higher in offspring of diabetic dams treated with antioxidant as compared to offspring of diabetic dams treated with vehicle (both P<0.01). There was no significant difference in fenoldopam-mediated urinary flow and urinary sodium excretion rate in offspring of control dams treated with antioxidant or vehicle (urinary flow: P=0.772; urinary sodium excretion rate: P=0.716). Compared with offspring of control dams treated with vehicle, the renal MDA activity was significantly increased, while the SOD activity was significantly decreased in offspring of diabetic dams treated with vehicle (MDA: P<0.01; SOD: P=0.013). The renal MDA activity was significantly decreased, while the SOD activity was significantly increased in offspring of diabetic dams treated with antioxidant in comparison with offspring of diabetic dams treated with vehicle (MDA: P<0.01; SOD: P=0.035).The renal GRK2 and GRK4 protein expression in offspring of diabetic dams treated with vehicle were significantly higher than those in offspring of control dams treated with vehicle (P<0.01), while the expression levels of renal GRK2 and GRK4 in offspring of diabetic dams treated with antioxidant were significantly downregulated compared with offspring of diabetic dams treated with vehicle (P<0.01). There was no significant difference in the protein expression of dopamine D(1) receptor among 4 groups (P=0.735). The level of dopamine D(1) receptor phosphorylation in offspring of diabetic dams treated with vehicle was significantly higher than that in offspring of control dams treated with vehicle (P<0.01), while the dopamine D(1) receptor phosphorylation level was significantly lower in offspring of diabetic dams treated with antioxidant compared to that in offspring of diabetic dams treated with vehicle (P<0.01). Conclusion: Oxidative stress is involved in the dopamine D(1) receptors dysfunction in the offspring of diabetic dams.

Sediment organic carbon and temperature effects on methylmercury concentration: A mesocosm experiment

The fate and mobility of mercury, and its bioaccumulation primarily as methylmercury (MeHg), in marine ecosystems are influenced by climate related environmental factors, including increased temperature and carbon loading. To investigate the interactions between sediment organic carbon and temperature MeHg bioaccumulation, mesocosm experiments were conducted examining relationships between sediment, water column and biota (sediment-dwelling amphipod and juvenile oyster) MeHg concentration. Experimental treatments consisted of a two by two design of high and low temperature (15 & 25 °C) and high and low sediment organic carbon (4-5% and 13% LOI, pre-experiment). Sediment organic carbon had significant individual effects on MeHg concentration in water and biota, with higher carbon associated with lower MeHg. Temperature individual effects were significant for sediment, water, and only amphipod MeHg concentration, with higher temperature treatments indicating higher MeHg concentration. There were significant temperature × carbon interactions observed for sediment, dissolved, and oyster MeHg concentration. Sediment carbon reduction had greater influence than temperature on increasing MeHg concentrations in both the water column and biota. MeHg concentrations in the bulk sediment were not correlated with MeHg in the water column or in the biota, indicating that even when sediments are the only source of MeHg, bulk sediment measurements do not provide a good proxy for bioaccumulation and that the concentration in bulk sediments is not the primary determinant of MeHg entry into the food web.

[Mycophenolate mofetil versus cyclosporine A in children with primary refractory nephrotic syndrome]

Objective: To compare the efficacy and safety of mycophenolate mofetil versus cyclosporine A in treating children with primary refractory nephrotic syndrome. Methods: Conducted a prospective randomized controlled clinical trial in 62 pediatric patients (including 44 boys and 18 girls), age ranged from 2.1 to 17.0 years; 32 cases presented with frequently relapsing nephrotic syndrome (FRNS) and 30 cases presented with steroid-resistant nephrotic syndrome (SRNS), who were admitted to department of Nephrology, Children's Hospital Affiliated to Capital Institute of Pediatrics from October 2013 to October 2015. The patients received either mycophenolate mofetil (20-30)mg/(kg·d) or cyclosporine A (3-5)mg/(kg·d) randomly, on the basis of prednisone treatment. Follow-up interview was conducted regularly for at least one year. Efficacy rate, relapse rate, time required for induction of remission, relapse-free period and prednisone dosage were compared between the two groups. Results: (1) Renal histologic examination, which was available for 17 patients, revealed minimal change disease in 8 patients, mesangial proliferative glomerulonephritis (MsPGN) in five, membranous nephropathy in two, and focal segmental glomerulosclerosis (FSGS) in two. (2) Comparison of mycophenolate mofetil versus cyclosporine A in children with FRNS: There were 14 patients with FRNS in mycophenolate mofetil group and 18 patients with FRNS in cyclosporine A group respectively. The relapse rate (episodes/year) in cyclosporine A group was lower than that of mycophenolate mofetil group (1.0 (0.0, 1.0) vs. 1.0 (1.0, 3.0), Z=-2.405, P=0.016). The relapse-free period (months) in cyclosporine A group was longer than that of mycophenolate mofetil group (10.0 (5.7, 12.1) vs. 5.0 (1.0, 11.0), Z=-1.984, P=0.047). No significant difference in dosage of prednisone was found between cyclosporine A and mycophenolate mofetil groups when followed up for 1 year. (3) Comparison of mycophenolate mofetil versus cyclosporine A in children with SRNS: The efficacy rate was 6/14 in mycophenolate mofetil group and 13/16 in cyclosporine A group. The complete remission rate was 4/14 in mycophenolate mofetil group and 12/16 in cyclosporine A group (P<0.05). The time (months) required for induction of remission in cyclosporine A group was significantly shorter than that of mycophenolate mofetil group (1.0 (1.0, 2.0) vs. 3.0 (2.5, 4.0), Z=-2.529, P=0.011). No significant differences were found between the two groups with respect to relapse-free period and relapse rate. (4) Except that one patient developed hypertensive encephalopathy in cyclosporine A group, no other serious adverse events were recorded. There were no significant differences between two groups with respect to adverse events. Conclusion: Our results indicated that both mycophenolate mofetil and cyclosporine A were effective in the treatment of children with refractory nephrotic syndrome. Cyclosporine A was superior to mycophenolate mofetil in preventing relapses in patients with FRNS and inducing complete remission in patients with SRNS. Although most patients were able to tolerate mycophenolate mofetil and cyclosporine A, but the toxicity and safety of cyclosporine A should be monitored closely.

First trimester placental vascular indices and volume by three-dimensional ultrasound in pre-gravid overweight women

OBJECTIVES

To investigate changes of placental vascular indices and volume in pre-gravid overweight Chinese women during the first trimester using three-dimensional power Doppler ultrasound.

METHODS

This was a prospective observational study of the morphology of placentas in pre-gravid overweight (body mass index (BMI) ≥ 24 kg/m²) and non-overweight (BMI < 24 kg/m²) Chinese women during the first trimester of pregnancy. Data on placental vascular indices (vascularization index, flow index, and vascularization flow index (VFI)), placental volume, uterine artery pulsatility index (PI), and neonatal outcomes were obtained during the first trimester and analyzed. Linear regression analysis was used to evaluate confounding factors between BMI and ultrasound indices.

RESULTS

Of the 429 pregnant women enrolled, 68 (15.9%) were pre-gravid overweight. Placental VFI was significantly lower in the overweight group (p = 0.037). Conversely, placental volume was significantly larger in the overweight group (p = 0.044), and uterine artery PI was significantly higher in the overweight group (p = 0.021). After adjustments for confounding factors, there were still significant differences in placental VFI (unstandardized coefficient (B) -0.666, 95% confidence interval (CI) -1.306 - (-0.025)), placental volume (B 2.458, 95% CI 0.071-4.844), and uterine artery PI (B 0.152, 95% CI 0.030-0.274) between the two groups.

CONCLUSIONS

Placental vascular indices using three-dimensional power Doppler ultrasound can provide an insight into placental vascularization in pre-gravid overweight women in early pregnancy. Alterations in placental VFI, placental volume, and uterine artery PI occur during the first trimester in pre-gravid overweight women.

Organic carbon content drives methylmercury levels in the water column and in estuarine food webs across latitudes in the Northeast United States

Estuaries are dynamic ecosystems which vary widely in loading of the contaminant methylmercury (MeHg), and in environmental factors which control MeHg exposure to the estuarine foodweb. Inputs of organic carbon and rates of primary production are important influences on MeHg loading and bioaccumulation, and are predicted to increase with changes in climate and land use pressures. To further understand these influences on MeHg levels in estuarine biota, we used a field study approach in sites across different temperature regions, and with varying organic carbon levels. In paired comparisons of sites with high vs. low organic carbon, fish had lower MeHg bioaccumulation factors (normalized to water concentrations) in high carbon sites, particularly subsites with large coastal wetlands and large variability in dissolved organic carbon levels in the water column. Across sites, MeHg level in the water column was strongly tied to dissolved organic carbon, and was the major driver of MeHg concentrations in fish and invertebrates. Higher primary productivity (chlorophyll-a) was associated with increased MeHg partitioning to suspended particulates, but not to the biota. These findings suggest that increased inputs of MeHg and loss of wetlands associated with climate change and anthropogenic land use pressure will increase MeHg concentrations in estuarine food webs.

Modelling the outbreak of infectious disease following mutation from a non-transmissible strain

In-host mutation of a cross-species infectious disease to a form that is transmissible between humans has resulted with devastating global pandemics in the past. We use simple mathematical models to describe this process with the aim to better understand the emergence of an epidemic resulting from such a mutation and the extent of measures that are needed to control it. The feared outbreak of a human–human transmissible form of avian influenza leading to a global epidemic is the paradigm for this study. We extend the SIR approach to derive a deterministic and a stochastic formulation to describe the evolution of two classes of susceptible and infected states and a removed state, leading to a system of ordinary differential equations and a stochastic equivalent based on a Markov process. For the deterministic model, the contrasting timescale of the mutation process and disease infectiousness is exploited in two limits using asymptotic analysis in order to determine, in terms of the model parameters, necessary conditions for an epidemic to take place and timescales for the onset of the epidemic, the size and duration of the epidemic and the maximum level of the infected individuals at one time. Furthermore, the basic reproduction number R0 is determined from asymptotic analysis of a distinguished limit. Comparisons between the deterministic and stochastic model demonstrate that stochasticity has little effect on most aspects of an epidemic, but does have significant impact on its onset particularly for smaller populations and lower mutation rates for representatively large populations. The deterministic model is extended to investigate a range of quarantine and vaccination programmes, whereby in the two asymptotic limits analysed, quantitative estimates on the outcomes and effectiveness of these control measures are established.

[Lipoxin A4 inhibits the invasion and migration of endometrial stromal cells by down-regulating NF-κB signaling-mediated autophagy]

Objective: To investigate whether the suppressive effects of lipoxin A4 (LXA4) on endometriosis are mediated by the regulation of autophagic activity, and to further explore the actual molecular mechanism. Methods: (1) Eutopic and ectopic endometria were obtained from 13 patients with endometriosis, and 10 eutopic endometria collected from non-endometriosis patients were used as control. The expression of the autophagy-related biochemical markers [microtubule-associated protein 1 light chain 3 (LC3) and p62] were detected by western blot. Levels of LXA4 in the biopsies were measured by ELISA. (2) Primary human endometrial stromal cells (ESC) were isolated and cultured in vitro from eutopic endometria of infertility patients with endometriosis. After treatment with exogenous LXA4 or autophagy inhibitor 3-methyladenine (3-MA) or autophagy inducer rapamycin, cell migration and invasion were evaluated by transwell assay, and autophagy was detected by western blot. (3) ESC were treated with LXA4, the gene expressions of nuclear factor kappa B (NF-κB) etc. were examined by quantitative real-time PCR, and the activation of NF-κB signaling was detected by western blot. (4) ESC were incubated with 10 μmol/L NF-κB inhibitor BAY11-7080, the autophagic activation was detected by western blot. Results: (1) Autophagy-related marker, LC3-Ⅱ and LC3-Ⅱ/LC3-Ⅰ ratio, showed a significant up-regulation in ectopic lesions of endometriosis compared with eutopic endometria of affected or healthy women (all P<0.05) . However, the LXA4 level significantly decreased in ectopic tissue (P<0.05) . There was a significant negative correlation between LXA4 concentration and relative expression of LC3-Ⅱ in ectopic lesions (r= -0.780, P=0.002) . (2) 10 and 100 nmol/L exogenous LXA4 could significantly down-regulate the LC3-Ⅱ protein expression and up-regulate the p62 protein expression (all P<0.05) . LXA4 markedly inhibited the invasion and migration of ESC (P<0.05) ;while the reactivation of autophagy by rapamycin almost reversed the anti-invasion and anti-migration effects of LXA4. (3) After LXA4 treatment, the expression level of NF-κB gene significantly decreased (P<0.05) . Furthermore, the results of western blot analysis showed that the nuclear translocation of NF-κB p65 was markedly down-regulated under LXA4 treatment (P<0.05) . (4) The NF-κB inhibitor BAY11-7080 markedly suppressed the autophagic activation of LXA4 (P<0.05) . Conclusion: LXA4 could inhibit the invasion and migration of ESC by down-regulating the NF-κB signaling-mediated autophagy.

Obesity-associated cardiac pathogenesis in broiler breeder hens: Development of metabolic cardiomyopathy

Feed intake is typically restricted (R) in broiler hens to avoid obesity and improve egg production and livability. To determine whether improved heart health contributes to improved livability, fully adult 45-week-old R hens were allowed to consume feed to appetite (ad libitum; AL) up to 10 wk (70 d). Mortality, contractile functions, and morphology at 70 d, and measurements of cardiac hypertrophic remodeling at 7 d and 21 d were made and compared between R and AL hens. Outcomes for cardiac electrophysiology and mortality, reported separately, found increased mortality in AL hens in association with cardiac pathological hypertrophy and contractile dysfunction. The present study aimed to delineate metabolic cardiomyopathies underlying the etiology of obesity-associated cardiac pathology. Metabolic measurements were made in hens continued on R rations or assigned to AL feeding after 7 d and 21 days. AL feeding increased plasma insulin, glucose, and non-esterified fatty acid (NEFA) concentrations by 21 d (P < 0.05). Metabolic cardiomyopathy in AL-hens was confirmed by cardiac triacylglycerol (TG) and ceramide accumulation consistent with up-regulation of related enzyme gene expressions, and by increased indices of oxidation stress (P < 0.05). In contrast to R hens, cardiac pyruvate dehydrogenase (PDH) activity and glucose transporter (GLUT) gene expressions increased progressively while carnitine palmitoyltransferase-1 (CPT-1) transcript levels in AL hens declined from 7 d to 21 d (P < 0.05), reflecting a shift from an oxidative to a more glycolytic metabolism, a typical metabolic derangement associated with cardiac hypertrophic remodeling. Cardiac pathogenesis in AL hens was further indicated by increased leukocyte infiltrates, interleukin-1β (IL-1β) and IL-6 production, cellular apoptosis, interstitial fibrosis, and expression of the heart failure marker myosin heavy chain (MHC-β; cardiac muscle beta) (P < 0.05). Results support the conclusion that diabetic conditions, cardiac inflammation and lipotoxic metabolic derangements act as pathological cues to trigger pathogenic changes along cardiac hypertrophy in AL hens.

Obesity-associated cardiac pathogenesis in broiler breeder hens: Pathological adaption of cardiac hypertrophy

Broiler hens consuming feed to appetite (ad libitum; AL) show increased mortality. Feed restriction (R) typically improves reproductive performance and livability of hens. Rapidly growing broilers can exhibit increased mortality due to cardiac insufficiency but it is unknown whether the increased mortality of non-R broiler hens is also due to cardiac compromise. To assess cardiac growth and physiology in fully mature birds, 45-week-old hens were either continued on R rations or assigned to AL feeding for 7 or 21 days. AL hens exhibited increased bodyweight, adiposity, absolute and relative heart weight, ventricular hypertrophy, and cardiac protein/DNA ratio by d 21 (P < 0.05). Increased heart weights due to hypertrophic growth was attributed to enhanced IGF-1-Akt-FoxO1 signaling and its downstream target, translation initiation factor 4E-BP1 in conjunction with down-regulation of ubiquitin ligase atrogin-1/MAFbx (P < 0.05). Reduced activation of cardiac AMPK and downstream activation of ACC-1 in parallel with increased cardiac nitric oxide levels, calcineurin activity, and MAPK activation in AL hens (P < 0.05) suggested that metabolic derangement develops along the cardiovascular remodeling. These indictors of cardiac maladaptive hypertrophic growth were further supported by uregulation of heart failure markers, BNP and MHC-β (P < 0.05). Hens allowed AL feeding for 70 d exhibited a higher incidence of mortality (40% vs. 10%) in association with ascites, pericardial effusion, and ventricle dilation. A higher incidence of irregular ECG patterns and rhythmicity consistent with persistently elevated systolic blood pressure and ventricle fibrosis were observed in AL hens (P < 0.05). These observations support the conclusion that AL feeding in broiler hens results in maladaptive cardiac hypertrophy that progresses to overt pathogenesis in contractility and thereby increases mortality. Feed restriction provides clear physiological benefit to heart function of adult broiler hens.

Technical note: Impact of pedigree depth on convergence of single-step genomic BLUP in a purebred swine population

In genomic evaluations, it is desirable to have low computing cost while retaining high accuracy of evaluation for young animals. When the population is large but only few animals have phenotypes, especially for low heritability traits, the convergence rate of BLUP or single-step genomic BLUP (ssGBLUP) can be very slow. This study investigates the effect of pedigree truncation on convergence rate and solutions of ssGBLUP for data exhibiting slow convergence. The data consisted of 216,000, 221,000, 732,000, and 579,000 phenotypes on 4 traits. Heritabilities were less than 0.1 for 2 traits and greater than 0.2 for the other 2 traits. The full pedigree consisted of 2.4 million animals. Genotypes were available for 33,000 animals and consisted of 60,000 SNP. Two bivariate animal models were fit using pedigree-based BLUP or ssGBLUP. Either a regular or the algorithm for proven and young (APY) inverse was used for the genomic relationship matrix. Different pedigree depths were analyzed including full pedigree and 1 to 5 ancestral generations. Pedigree depths were defined as n ancestral generations for animals with phenotypes. The number of animals in the reduced pedigrees varied from 226,000 and 760,000 for 1 generation to 228,000 and 767,000 for 5 generations. Genomic EBV (GEBV) for genotyped animals had correlations greater than 0.99 between runs with the full and reduced pedigrees with 2 to 5 generations. A single generation of pedigree was not sufficient to obtain the same GEBV as full pedigree. The convergence rate was the worst with the full pedigree and generally improved with reduced pedigrees. Using ssGBLUP with the APY inverse improved convergence without affecting accuracy. Reducing pedigrees and the APY are important tools to reduce the computational cost in the implementation of ssGBLUP.

Anesthesia for patients with tracheal bronchus

Tracheal bronchus is a congenital anatomical variant of patients with accessory bronchus in the right upper lobe deriving directly from the supracarinal trachea. Pre-operative consultation with the anesthesiologist is important for patient safety and can avoid adverse effects induced by endotracheal intubation. In this report, we described a case of tracheal bronchus in which general anesthesia was performed for video-assisted thoracoscopic surgery. We discussed some of the issues surrounding to complications in tracheal bronchus.

T1 mapping combined with Gd-EOB-DTPA-enhanced magnetic resonance imaging in predicting the pathologic grading of hepatocellular carcinoma

The aim of this study was to investigate the value of Gd-EOB-DTPA-enhanced MRI on hepatobiliary phase (HBP) imaging and T1 mapping sequence in the differentiation of hepatocellular carcinoma (HCC). A total of 45 patients with HCC who were to undergo a resection were enrolled in this study. Gd-EOB-DTPA-enhanced magnetic resonance examination was performed prior to resection. T1 mapping was performed before and 20 min after injection of Gd-EOB-DTPA. T1 values of the lesions were measured on pre-contrast (T1p) and during HBP (T1-HBP) on T1 maps. The signal intensity, the diameter and the margin of HCC lesions on HBP images were analyzed. The reduction in T1 value (T1d) and the reduction rate (ΔT1%) of T1 mapping between pre-contrast and HBP were calculated. The Edmondson-Steiner classification of each lesion was made after surgery. The SPSS software package was used for statistical analysis and the analysis of receiver operator characteristic (ROC) curve and area under the curve (AUC) were carried out by using MedCalc software package. Mean values of T1p and T1-HBP were 1935.4±730.8 ms and 1257.1±529.1 ms, respectively. T1p accuracy (AUC = 0.685, p = 0.037) in predicting pathological grading was similar to that of T1-HBP (AUC = 0.751, p = 0.005). A T1p of 1648.2 ms or greater had a sensitivity and specificity of 85.19% and 61.11%, respectively. A T1-HBP of 1006 ms or greater had a sensitivity and specificity of 81.84% and 61.11%, respectively. The number of HCCs with a non-smooth tumor margin was 20 (44.4%), and a non-smooth tumor margin correlated moderately with the Edmondson-Steiner grade (Spearman r = 0.491, p = 0.041). There was no significant correlation between T1d, ΔT1%, HCC signal intensity on HBP image and lesion diameter with pathologic grading. T1 mapping in pre-contrast and HBP of Gd-EOB-DTPA-enhanced MRI, a non-smooth tumor margin in the HBP of Gd-EOB-DTPA-enhanced MRI, are useful in predicting the pathologic grading of HCC.

[Helicobacter pylori eradication and gastroesophageal reflux disease: a Meta-analysis]

OBJECTIVE

To systematically evaluate whether eradication of Helicobacter pylori (H.pylori) is associated with the development of endoscopic gastroesophageal reflux disease (GERD) and reflux symptoms.

METHODS

PubMed, CENTRAL, Embase, CNKI and Wanfang Database from April 1978 to April 2015 were retrieved to collect the randomized controlled trials (RCTs) comparing the incidence of reflux symptoms or reflux esophagitis in patients receiving H. pylori eradication treatment and those without treatment. The quality of trials was evaluated by the Cochrane Collaboration's tool for assessing risk of bias and Jadad scoring. A Meta-analysis was conducted by using RevMan 5.20 software.

RESULTS

Twenty RCTs involving 6 575 cases were included. Meta-analysis showed that: (1) There was a positive link between H. pylori eradication and endoscopic reflux esophagitis. The diagnostic rate of endoscopic reflux esophagitis after H. pylori eradication therapy was higher than that of control group(7.25% vs 4.20%; OR=1.62, 95%CI 1.20-2.19, P=0.002). Subgroup analysis found that Asian patients, 40 to 50 years old, follow-up time more than 1 year, and peptic ulcer had higher incidence of endoscopic reflux esophagitis; (2) The incidence of reflux symptoms was not significantly different between H. pylori eradication group and control group (25.2% vs 24.6%; OR=1.03, 95%CI 0.87-1.21, P=0.76). Further analysis indicated that reflux symptoms were not related to some relevant factors, such as races, age at diagnosis, follow-up time and underlying diseases.

CONCLUSIONS

The eradication of H. pylori is considered as one of risk factors for GERD, especially in Asian populations, long time follow-up, 40 to 50 years old and patients with peptic ulcer. Meanwhile, the eradication of H. pylori does not suggest the correlation with reflux symptoms. H. pylori eradication therapy should be administrated according to patients' individual conditions.

[Changes of adherens junctions between the epithelial cells of intestinal mucosal barrier in irritable bowel syndrome]

Objective: To investigate whether there are changes in adherens junctions(AJ), including E-cadherin (E-cad) and β-catenin (β-cat), in the colonic mucosa of irritable bowel syndrome (IBS). Methods: Colorectal dilatation combined with restraint stress was used to establish IBS SD rat model. There were 8 rats in the model group and 8 rats in normal control group. From each rat, the colon tissue 5 centimeters away from ileocecum (I) and the junction of the rectum and sigmoid colon (R) were taken, in which E-cad and β-cat mRNA, protein level and structural changes were detected using real-time quantitative-PCR, Western blot, and immunofluorescence. According to the Rome Ⅲ criteria, IBS with diarrhea (IBS-D) patients receiving colonoscopy (n=17) and healthy volunteers (n=17) were enrolled in Center of Endoscopy of the First Affiliated Hospital of Zhejiang Chinese Medicine University. The colon tissues of I and R locations were collected from them. Colonic epithelial cell AJ protein expression and AJ structural changes in the tissues were detected using Western blot, immunofluorescence and transmission electron microscope (TEM). Results: (1)Both in I and R sites, the mRNA and protein expression of E-cad in IBS rats were both significantly lower than in normal SD rats (all P<0.05). The mRNA expression of β-cat showed no significant change in IBS SD rats compared with the normal SD rats; the protein expression of β-cat was decreased in I(P<0.05), no significantly different in R. (2)In I and R of IBS-D patients, the expression of E-cad protein were significantly decreased(I: 0.85±0.30 vs 1.24±0.34, P=0.00; R: 0.86±0.17 vs 1.14±0.48, P=0.05); the protein expression of β-cat also showed significant reduction both in I(0.85±0.39 vs 1.22±0.51, P=0.04)and R (0.92±0.22 vs 1.16±0.31, P=0.02) of IBS-D patients, compared with the healthy controls. Immunofluorescence results showed that E-cad and β-cat in colonic epithelial cells of I and R in the healthy controls were distributed along the cell membrane, demonstrating honeycomb linear fluorescence; however, in IBS-D patients, the structure of E-cad and β-cat were fuzzy, with disrupted distribution in the cytoplasm. Under TEM, the gaps of AJ in I and R of IBS-D patients appeared wider than in the healthy volunteers. Conclusions: In IBS-D patients, there are wider gaps of AJ, and decreased expression with structural disorder of E-cad and β-cat in the colon. The change of AJ plays an important role in the damage of colonic mucosal barrier and the increase of intestinal epithelial permeability in IBS-D patients, but the mechanism is yet to be further explored.

[Value of MDM2, CDK4 and SATB2 immunohistochemistry in histologic diagnosis of low-grade osteosarcoma]

OBJECTIVE

To investigate the value of combined application of MDM2, CDK4 and SATB2 immunohistochemistry in pathological diagnosis of low-grade osteosarcoma.

METHODS

Forty-seven cases of low grade osteosarcoma, including low grade central osteosarcoma (n=20) and parosteal osteosarcoma (n=27), were selected from Shanghai Jiaotong University Affiliated the Sixth People's Hospital. The clinical, radiography and histopathology were reviewed. The sensitivity and specificity of MDM2, CDK4 and SATB2 immunohistochemistry in the diagnosis of low-grade osteosarcoma were assessed along with an evaluation of their expressions in fibrous dysplasia, desmoplastic fibroma, low-grade fibrosarcoma and other fibrous tumors.

RESULTS

Low-grade osteosarcoma had protracted clinical course, occurring mostly in elder adults and mainly involving long bones. Radiographic studies showed that low-grade central osteosarcoma had a mainly malignant lytic presentation, however about 5/18 of tumors overlapping with intermediate and benign bone diseases, while parosteal osteosarcoma was characterized by a densely sclerotic malignant appearance. Histologically, low-grade osteosarcomas were characterized by well-differentiated spindle tumor cells, various mature tumor bones and an aggressive growth pattern. The positive expression rates of MDM2 and CDK4 in low-grade osteosarcoma were 74.5% and 55.3%, respectively. Eighty-three percent of low-grade osteosarcoma expressed one or both markers. Low-grade osteosarcoma and fibrous dysplasia were both positive for SATB2, while desmoplastic fibroma, low-grade fibrosacoma and other fibrous tumors were negative for SATB2.

CONCLUSIONS

Accurate diagnosis of low-grade osteosarcoma should be based on combination of clinical presentation, imaging and histopathology, with immunohistochemistry as a diagnostic adjunct. Positive immunostaining for CDK4 and/or MDM2 supports the diagnosis of low-grade osteosarcoma, but the negative one does not rule out such lesion. The negative expression of SATB2 is helpful to exclude fibrous tumors originating from bone with the exception of fibrous dysplasia.

Trajectories of Nutritional Status and Cognitive Impairment among Older Taiwanese with Hip Fracture

OBJECTIVE

This paper describes the trajectories of nutritional status and cognitive impairment and their correlation among older Taiwanese over 1 year after hip-fracture surgery.

DESIGN

Secondary analysis of data from a clinical trial evaluating the effects of three types of post-discharge care for 292 older hip-fracture patients (age >60 years).

MEASUREMENTS

Nutritional status was assessed by the Mini Nutritional Assessment before and 1, 3, 6, 12 months after hospital discharge. Cognitive function was measured by the Mini-Mental State Examination before surgery, at hospital discharge, 6 and 12 months after discharge. Trajectories of nutritional status and cognitive impairment were depicted by latent class growth modeling, whereas linkages between nutritional-status and cognitive-impairment trajectories were assessed by multinomial logistic regression.

RESULTS

Nutritional status in general improved significantly, particularly during the first 3 months after discharge. We identified three trajectories of nutritional status: malnourished (15.4%), at risk for malnutrition (38.9%), and well-nourished (45.7%). In contrast, cognitive changes followed four largely linear but distinct trajectories: moderately impaired (12.2%), mildly impaired (27.8%), borderline impaired (21.8%), and cognitively intact (38.2%). Trajectories of nutritional status were significantly associated with cognitive-function trajectories. For instance, relative to malnourished patients, well-nourished patients were 95% less likely (OR=0.05, CI =0.01-0.24) to be moderately cognitively impaired.

CONCLUSION

A good nutritional-status trajectory after hip fracture was associated with better cognitive function. To treat and care for elderly hip-fractured patients, specific interventions need to target those who are malnourished or at risk of malnutrition to decrease their risk for cognitive impairment.

Impact of platelet pathogen inactivation on blood component utilization and patient safety in a large Austrian Regional Medical Centre

BACKGROUND

In clinical studies, pathogen inactivation (PI) of platelet concentrates (PC) with amotosalen and UVA light did not impact patient risk for haemorrhage but may affect transfusion frequency and component utilization. We evaluated the influence of platelet PI on PC, red cell concentrate (RCC) and plasma use and safety in routine practice in a large regional hospital.

STUDY DESIGN AND METHODS

Comparative effectiveness of conventional vs. PI-treated PC was analysed during two 21-month periods, before and after PI implementation.

RESULTS

Similar numbers of patients were transfused in the pre-PI (control, 1797) and post-PI (test, 1694) periods with comparable numbers of PC (8611 and 7705, respectively). The mean numbers of PC per patient transfused (4·8 vs. 4·5, P = 0·43) were not different but days of PC support (5·9 vs. 5·0, P < 0·01) decreased. Most patients received RCC (86·8% control vs. 84·8% test, P = 0·90) with similar mean numbers transfused (10·8 vs. 10·2 RCC, P = 0·22), and fewer patients (55·4% control vs. 44·7% test, P < 0·01) received less plasma units (mean 9·9 vs. 7·8, respectively, P < 0·01) in the test period. The frequencies of transfusion-related adverse events (AE) were comparable (1·3% vs. 1·4%, P = 0·95). Analysis of haematology-oncology (522 control, 452 test), cardiac surgery (739 control, 711 test), paediatric (157 control, 130 test) and neonate (23 control, 20 test) patients revealed no increase in PC, plasma and RCC utilization, or AE.

CONCLUSION

Component utilization and patient safety were not impacted by adoption of PI for PC. RCC use per patient was comparable, suggestive of no increase in significant bleeding.

Crossbreed evaluations in single-step genomic best linear unbiased predictor using adjusted realized relationship matrices

Combining purebreed and crossbreed information is beneficial for genetic evaluation of some livestock species. Genetic evaluations can use relationships based on genomic information, relying on allele frequencies that are breed specific. Single-step genomic BLUP (ssGBLUP) does not account for different allele frequencies, which could limit the genetic gain in crossbreed evaluations. In this study, we tested the performance of different breed-specific genomic relationship matrices () in ssGBLUP for crossbreed evaluations; we also tested the importance of genotyping crossbred animals. Genotypes were available for purebreeds (AA and BB) and crossbreeds (F) in simulated and real pig populations. The number of genotyped animals was, on average, 4,315 for the simulated population and 15,798 for the real population. Cross-validation was performed on 1,200 and 3,117 F animals in the simulated and real populations, respectively. Simulated scenarios were under no artificial selection, mass selection, or BLUP selection. Two genomic relationship matrices were constructed based on breed-specific allele frequencies: 1) , a genomic relationship matrix centered by breed-specific allele frequencies, and 2) , a genomic relationship matrix centered and scaled by breed-specific allele frequencies. All (the across-breed genomic relationship matrix), , and were also tuned to account for selective genotyping. Using breed-specific allele frequencies reduced the number of negative relationships between 2 purebreeds, pulling the average closer to 0, as in the pedigree-based relationship matrix. For simulated populations that included mass selection, genomic EBV (GEBV) in F, when using and , were, on average, 10% more accurate than ; however, after tuning to account for selective genotyping, provided the same accuracy as for breed-specific genomic relationship matrices. For the real population, accuracies for litter size in F were 0.62 for , , and , and tuning had no impact on accuracy, except for , which was 1 percentage point less accurate. Accuracy of GEBV for number of stillborns in F1 was 0.5 for all tested genomic relationship matrices with no changes after tuning. We observed that genotyping F increased accuracies of GEBV for the same animals by up to 39% compared with having genotypes for only AA and BB. In crossbreed evaluations, accounting for breed-specific allele frequencies promoted changes in G that were not influential enough to improve accuracy of GEBV. Therefore, the best performance of ssGBLUP for crossbreed evaluations requires genotypes for pure- and crossbreeds and no breed-specific adjustments in the realized relationship matrix.

Single toxin dose-response models revisited

The goal of this paper is to offer a rigorous analysis of the sigmoid shape single toxin dose-response relationship. The toxin efficacy function is introduced and four special points, including maximum toxin efficacy and inflection points, on the dose-response curve are defined. The special points define three phases of the toxin effect on mortality: (1) toxin concentrations smaller than the first inflection point or (2) larger then the second inflection point imply low mortality rate, and (3) concentrations between the first and the second inflection points imply high mortality rate. Probabilistic interpretation and mathematical analysis for each of the four models, Hill, logit, probit, and Weibull is provided. Two general model extensions are introduced: (1) the multi-target hit model that accounts for the existence of several vital receptors affected by the toxin, and (2) model with a nonzero mortality at zero concentration to account for natural mortality. Special attention is given to statistical estimation in the framework of the generalized linear model with the binomial dependent variable as the mortality count in each experiment, contrary to the widespread nonlinear regression treating the mortality rate as continuous variable. The models are illustrated using standard EPA Daphnia acute (48h) toxicity tests with mortality as a function of NiCl or CuSO₄ toxin.