From cutting edge to guideline: A first step in harmonization of the zebrafish embryotoxicity test (ZET) by describing the most optimal test conditions and morphology scoring system

In the last couple of years, the interest in the zebrafish embryotoxicity test (ZET) for use in developmental toxicity assessment has been growing exponentially. This is also evident from the recent proposal for updating the ICHS5 guideline. The methodology of the ZET used by the different groups varies greatly. To further evaluate its successfulness and to take the ZET to the next level, harmonization of procedures is crucial. In the present study, based on literature and empirical data, the most optimal study design regarding temperature, test chamber, exposure period, presence of chorion, solvent use, exposure method, choice of concentrations, and teratogenic classification is proposed. Furthermore, our morphology scoring system is reported in detail as protocol to further enhance study design harmonization.     

Peri-pubertal administration of 3-nitro-1,2,4-triazol-5-one (NTO) affects reproductive organ development in male but not female Sprague Dawley rats

Nitrotriazolone (3-nitro-1,2,4-triazol-5-one; NTO) is an insensitive munition that has demonstrated effects on reproductive organs in adult male rats. NTO was administered to male (0, 250, and 500 milligrams per kilogram per day (mg/kg-day)) and female (0, 500, and 1000 mg/kg-day) Sprague-Dawley rats (15/sex/group) via oral gavage from weaning through post-natal day 53/54 and 42/43, respectively. Age and body mass at vaginal opening (VO) and preputial separation (PPS), as well as all measures of estrous cyclicity were not affected by treatment with NTO. Males treated with NTO exhibited reductions in testis mass associated with tubular degeneration/atrophy. Less pronounced reductions in accessory sex organ masses were also observed in the 500 mg/kg-day group. Treatment with NTO did not affect thyroid hormone or testosterone levels. These findings suggest that NTO is not acting as an estrogen or thyroid active compound, but may indicate effects on steroidogenesis and/or direct testicular toxicity.     

The comparative epidemiology and outcomes of hospitalized patients treated with SGLT2 or DPP4 inhibitors

ObjectiveTo compare the outcomes of sodium glucose linked cotransporter 2 inhibitors (SGLT2i) and dipeptidyl peptidase 4 inhibitors (DPP4i) in hospitalized patients.Research design and methodsElectronic medical records-based cohort study. Identification of patients with type 2 diabetes and treatment with SGLT2i (n = 466) or DPP4i (n = 1541). Outcomes compared between those who received SGLT2i and those who received DPP4i. The primary outcome: adjusted percentage of blood glycemia within 4-10 mmol/L.ResultsAfter adjustment, SGLT2i use had a statistically equivalent percentage of glycemia within range (coefficient: 4.55, 95% CI -3.23 to 12.32, p = 0.25) or <4 mmol/L (coefficient −0.17, 95% CI −0.71 to 3.72, p = 0.54). There were no significant differences in hospital length of stay (p = 0.22), complications, (p = 0.11) or mortality (p = 0.57). When measured, ketone levels were higher in the SGLT2i group on admission, but lower on days 3, 4 and 5 (p < 0.001 for interaction). Bicarbonate levels were not statistically different between groups. Finally, 54% of patients whose SGLT2i was ceased during admission, were discharged home without it.ConclusionAmong inpatients with type 2 diabetes, SGLT2i use was associated with equivalent within-target glycaemia and no significant increase in hypoglycemia, ketonemia, or lower bicarbonate levels. These hypothesis-generating findings support further investigation of SGLT2i therapy in inpatients.     

Relationship between myeloperoxidase promotor polymorphism and disease severity in sarcoidosis

Previously, we demonstrated that the number of polymorphonuclear neutrophils (PMNs) in bronchoalveolar lavage fluid (BALF) is useful in distinguishing sarcoidosis patients with a favorable outcome from those having a more severe course of disease. Neutrophils contain the oxidant-generating enzyme myeloperoxidase (MPO). Cellular levels of MPO can be influenced by functional promotor polymorphisms, ?463G/A and ?129G/A, which may modify disease severity.     

Polyamine Levels in the Pancreas and the Blood Change according to the Severity of Pancreatitis

Background/Aims: Polyamines are essential to survival, growth, and proliferation of mammalian cells. Previous studies have suggested that the pancreatic polyamine levels may change in acute pancreatitis. In this study, the changes of polyamine levels in the pancreas have been studied with respect to the severity of pancreatitis. We investigated whether there is a relationship in polyamine levels between pancreas and blood, and whether pancreatic and blood polyamine levels change according to the severity of pancreatitis. Methods: In rats, sublethal pancreatitis was induced by intraductal infusion of 2% taurodeoxycholate, while lethal pancreatitis was induced with 6% taurodeoxycholate. Results: Infusion of 6% taurodeoxycholate as compared with 2% resulted in more severe pancreatitis, as revealed by mortality, histology, and serum amylase activity. Pancreatic spermidine/spermine N¹-acetyltransferase was induced early after pancreatitis and was associated with increased putrescine and decreased spermidine levels. The extent of pancreatic necrosis significantly correlated with the polyamine catabolism indicators pancreatic putrescine/spermidine ratio (r = 0.29, p < 0.01) and pancreatic putrescine/spermine ratio (r = 0.32, p < 0.01). The two pancreatic polyamine ratios correlated well also with the red blood cell polyamine ratios (r = 0.75 and r = 0.72, respectively, both p < 0.01). Furthermore, the extent of pancreatic necrosis correlated with red blood cell putrescine/spermidine (r = 0.32, p < 0.01) and putrescine/spermine (r = 0.37, p < 0.01) ratios. Conclusions: Acute experimental pancreatitis is associated with an early pancreatic spermidine/spermine N¹-acetyltransferase induction and consequent changes in polyamine levels in pancreas and red blood cells, depending on the severity of pancreatitis. Because changes in red blood cell spermidine, spermine, and putrescine levels evolve already early during the time course of pancreatitis, and correlate with the extent of pancreatic necrosis, their clinical value as early markers of the severity of acute pancreatitis needs to be further evaluated. Copyright © 2008 S. Karger AG, Basel and IAP     

Taurine improves neuron injuries and cognitive impairment in a mouse Parkinson’s disease model through inhibition of microglial activation

Clinical and experimental findings support the view that activation of hippocampus microglia through NADPH oxidase contributes to cognitive impairment in Parkinson's disease (PD). Taurine, an antioxidant, displays an exclusive physical property on brain function, such as learning and memory. To date, the role of taurine in improving cognitive impairment in PD is not fully uncovered. Hence, we evaluated the protective effect of taurine on cognitive ability and explored the related mechanism in the model built by paraquat and maneb (P + M)-induced PD mice. Then the ability of learning and memory was observed by Morris water maze, neuron loss was evaluated by immunohistochemistry in hippocampus, the level of postsynaptic density 95 (PSD95) and microglia activation was assessed by immunostaining, the molecules (gp91^phox, p47^phox, mac1, p-Src/Src and p-Erk/Erk) were examined by western blot. The results showed that taurine could alleviate the impairments in learning and memory induced by P + M injection in mice (decreased escape latency on day 4, P < 0.01; decreased swimming distance on day 4, P < 0.05; increased percent time in target quadrant, P < 0.05), corresponding with activation of microglia (decreased IBa-1 density, P < 0.001; decreased the protein expression of p47^phox, P < 0.05; decreased protein expression of gp91^phox, P < 0.01; decreased p-Src/Src, P < 0.01; decreased p-Erk/Erk, P < 0.01; decreased mac 1, P < 0.01), decreased neuron loss (increased number of NeurN⁺ neuron, P < 0.001; increased protein expression of NeruN, P < 0.01; decreased protein expression of caspase 3, P < 0.01) and increased PSD95 level in hippocampus (P < 0.01). The results indicated that mac1 and Src-Erk signaling was involved in increased NADPH oxidase expression in hippocampus microglia of P + M mice, and taurine could improve injuries in learning and memory through mac1 reduction. The new findings in mac1 triggering hippocampal microglia NADPH oxidase through Src/Erk pathway of the present study might provide a therapy target for PD.     

Metabolic profiling in human SH-SY5Y neuronal cells exposed to perfluorooctanoic acid (PFOA)

Perfluorooctanoic acid (PFOA) is an abundant per- and polyfluoroalkyl substance (PFAS) detected in both indoor and outdoor environments. While studies suggest exposure concerns for humans, studies investigating PFOA-induced neurotoxicity are lacking. To address this gap, we exposed differentiated human SH-SY5Y cells to PFOA (0.1 μM up to 500 μM) at different time points (4, 24, 48, and 72 h) and measured cell viability, Casp3/7 activity, ATP levels, ATP synthase enzyme activity, mitochondrial membrane potential, reactive oxygen species (ROS), oxygen consumption rates for mitochondrial stress test (XFe24 Flux analyzer), glucose utilization, and global metabolome profiles to assess the potential for PFOA-induced neurotoxicity. Treatment with 10 or 100 μM PFOA did not compromise cell viability nor induce cytotoxicity to SH-SY5Y cells over a 48-hour exposure period. However, >250 μM PFOA compromised cell viability, induced cytotoxicity, and induced caspase 3/7 activity at 48 h. ATP levels were reduced in cells treated with 400 μM PFOA for 24 and 48 h, and with 100 μM PFOA and higher at 72 h. ATP synthase activity was inhibited by 250 μM PFOA but was unchanged by PFOA treatment at 200 μM or less. Conversely, mitochondrial membrane potential was reduced by >10 μM PFOA after 24 h. Total ROS was increased with 100 μM PFOA and higher after 4 h of exposure. Several mitochondria-related endpoints (basal respiration, ATP production, maximum respiration) were negatively affected at 250 μM PFOA at both 24- and 48-hour exposure, but were unaltered at concentrations of 100 μM PFOA or less. One exception was mitochondrial spare capacity, which was reduced by 100 μM PFOA after 24-hour exposure. Similarly, glycolysis, glycolytic capacity, and glycolytic reserve of SH-SY5Y cells were not altered by 10 nor 100 μM PFOA. Nontargeted metabolomics was conducted in cells treated with either 10 or 100 μM PFOA for 48 h, as these two concentrations were not cytotoxic and 28 metabolites differed among treatments. Notable was that 10 μM PFOA had little effect on the SH-SY5Y metabolome, and the metabolic profile was not statistically different from media nor solvent controls. On the other hand, 100 μM PFOA shifted the metabolic signature of the neuronal cells, leading to reduced abundance of ATP-related metabolites (adenine, nicotinamide), neurotransmitter precursors (DL-tryptophan, l-tyrosine), and metabolites that protect mitochondria during oxidative stress (betaine, orotic acid, and l-acetyl carnitine). We hypothesize that this metabolic signature may be associated with the reduced mitochondrial membrane potential observed at lower PFOA concentrations. Metabolic shifts appear to precede compromised cell viability, cytotoxicity, and apoptosis. This study generates mechanistic knowledge regarding PFOA-induced neurotoxicity, focusing on mitochondrial oxidative respiration and the neuronal metabolome.     

Multispectral characterization of tissues encountered during laparoscopic colorectal surgery

AimsThis study investigated the feasibility of automated differentiation between essential tissue types encountered during laparoscopic colorectal surgery using spectral analysis.MethodsWide band (440–1830 nm) spectra were collected using an optical fiber probe and spectrometer from freshly explanted, ex vivo, human colonic specimens. These data were normalized at 810 nm (an isobestic wavelength for hemoglobin and oxy-hemoglobin) and mathematically analyzed using total principal component regression (TPCR).Results929 spectra were collected from specimens of 19 patients, distinguishing 5 tissue types: mesenteric fat (MF, n = 269), blood vessels (BV, n = 377), colonic tissue (CT, n = 213), ureter (UR, n = 10) and tumorous tissue in colon (TT, n = 60). For each individual tissue type the distinctive ability was determined against all other tissue types pooled as a group. Paired probability density function (PDF) of “tissue” (centered around label 1) versus “all other pooled tissues” (centered around label 0) and the cumulative distribution function (CDF) at label crossover value 0.5 was determined for each tissue type (MF: CDF = 0.99 [SD = 0.19]; BV: CDF = 0.95 [SD = 0.29]; CT: CDF = 0.98 [SD = 0.22]; UR: CDF = 0.99 [SD = 0.09]; TT: CDF = 0.99 [SD = 0.18]).ConclusionAutomated spectral differentiation of blood vessel, ureter, mesenteric adipose tissue, colonic tissue and tumorous tissue in colon, is feasible in freshly explanted human colonic specimens. These results may be exploited for further steps toward multi- or hyperspectrally enhanced in vivo (laparoscopic) surgical imaging.     

Recovery of live virus after storage at ambient temperature using ViveST™

BackgroundA major impediment to performing virological field studies in developing nations is the lack of ultra-low freezers as well as the expense and difficulty of shipping frozen samples. A commercially available product, ViveST?, was developed to preserve nucleic acids at ambient temperature for use in specimen storage and transportation. However, its applications as a viral storage, transport and recovery device have not been evaluated.ObjectiveTo examine the ability of ViveST to preserve live virus following storage at ambient temperature.Study designA panel of six viruses was stored at ambient temperature (～22 °C) in ViveST with fetal bovine serum (FBS), or ViveST with minimal essential media (MEM) and compared with virus stored in universal transport media (M4RT), MEM, and FBS alone. Stored viruses included: human adenovirus (14p), dengue virus 2 (16608), echovirus 3 (Morrisey), human rhinovirus 15 (1734), Coxsackie virus B5 (Faulkner), and herpes simplex virus 1 (HF). After 7 days storage at ambient temperature, virus recovery was measured via titration using viral plaque assays or focus-forming unit assays.ResultsViral titer studies indicate that ViveST with either FBS or M4RT preserved/recovered 5 different viruses for 1 week at ambient temperature. MEM preserved 4 viruses while FBS and ViveST with MEM preserved 3 viruses each. Statistical analyses indicate that M4RT and ViveST with FBS preserved significantly more virus than the other treatments.ConclusionsThese data suggest that ViveST with either FBS or M4RT may be useful in field specimen collection scenarios where ultra-cold storage is not available.