Effect of high- and low-energy entrance surface dose allocation ratio for two-shot dual-energy subtraction imaging on low-contrast resolution.

INTRODUCTION: Dual-energy subtraction (DES) imaging can obtain chest radiographs with high contrast between nodules and healthy lung tissue, and evaluating of chest radiography and evaluating exposure conditions is crucial to obtain a high-quality diagnostic image. This study aimed to investigate the effect of the dose allocation ratio of entrance surface dose (ESD) between high- and low-energy projection in low-contrast resolution of soft-tissue images for two-shot DES imaging in digital radiography using a contrast-detail phantom (CD phantom). METHODS: A custom-made phantom mimicking a human chest that combined a CD phantom, polymethylmethacrylate square plate, and an aluminum plate (1-3 mm) was used. The tube voltage was 120 kVp (high-energy) and 60 kVp (low-energy). The ESD was changed from 0.1 to 0.5 mGy in 0.1 mGy increments. Dose allocation ratio of ESD between 120 kVp and 60 kVp projection was set at 1:1, 1:2, 1:3, and 2:1. Inverse image quality figure (IQFinv) was calculated from the custom-made phantom images. RESULTS: When the total ESD and aluminum thickness were constant, no significant difference in IQFinv was observed under most conditions of varied dose allocation ratio. Similarly, when the total ESD and the dose allocation ratio were constant, there was no significant difference in IQFinv based on the aluminum plate thickness. CONCLUSION: Using IQFinv to evaluate the quality of the two-shot DES image suggested that dose allocation ratio did not have a significant effect on low-contrast resolution of soft-tissue images. IMPLICATIONS FOR PRACTICE: The present results provide useful information for determining exposure conditions for two-shot DES imaging.

A multi-centre, retrospective case series of oocyte cryopreservation in unmarried women diagnosed with haematological malignancies.

STUDY QUESTION: Is oocyte cryopreservation an applicable option for fertility preservation in unmarried patients with haematological malignancies? SUMMARY ANSWER: Oocyte cryopreservation via the vitrification method is accessible and may be considered an option for fertility preservation in unmarried patients with haematological malignancies. WHAT IS KNOWN ALREADY: Haematological malignancies are most commonly observed amongst adolescent and young adult women. Although the survival rate and life expectancy of those with haematological malignancies have improved, chemotherapy and radiotherapy may impair their reproductive potential. Oocyte cryopreservation is thus an ideal option to preserve their fertility. STUDY DESIGN SIZE DURATION: This study retrospectively evaluated 193 unmarried patients (age: 26.2 ± 0.4 years) with haematological malignancies, who consulted for oocyte cryopreservation across 20 different fertility centres in Japan between February 2007 and January 2015. The primary outcome measures were the oocyte retrievals and oocyte cryopreservation outcomes. The secondary outcome measures were the outcomes following oocyte warming for IVF. PARTICIPANTS/MATERIALS SETTING METHODS: The patients had commenced ovarian stimulation cycles via antagonist, agonist, natural and minimal methods for oocyte retrievals, defined according to the treatment strategy of each respective fertility centre. A vitrification method using the Cryotop safety kit was used for oocyte cryopreservation. ICSIs were used for insemination of warmed oocytes. The endometrial preparation method for embryo transfer was hormonal replacement therapy, except in the case of a patient who underwent a spontaneous ovulatory cycle. MAIN RESULTS AND THE ROLE OF CHANCE: Among 193 patients, acute myeloid leukaemia (n = 45, 23.3%) was most common, followed by acute lymphoid leukaemia (n = 38, 19.7%) and Hodgkin's lymphoma (n = 30, 15.5%). In total, 162 patients (83.9%) underwent oocyte retrieval, and oocytes were successfully cryopreserved for 155 patients (80.3%). The mean number of oocyte retrieval cycles and cryopreserved oocytes were 1.7 ± 0.2 and 6.3 ± 0.4, respectively. As of December 2019, 14 patients (9.2%) had requested oocyte warming for IVF. The survival rate of oocytes after vitrification-warming was 85.2% (75/88). The rates of fertilisation and embryo development were 80.0% (60/75) and 46.7% (28/60), respectively. Ten patients (71.4%) had successful embryo transfers, and seven live births (50.0%) were achieved. LIMITATIONS REASONS FOR CAUTION: This study was limited by its retrospective nature. Additionally, there remains an insufficient number of cases regarding the warming of vitrified oocytes to reliably conclude whether oocyte cryopreservation is effective for patients with haematological malignancies. Further long-term follow-up study is required. WIDER IMPLICATIONS OF THE FINDINGS: Oocyte retrieval and oocyte cryopreservation were accessible for patients with haematological malignancies; however, the number of oocyte retrievals may have been limited due to the initiation of cancer treatments. Acceptable embryonic and pregnancy outcomes could be achieved following oocyte warming; therefore, our results suggest that oocyte cryopreservation can be considered an option for fertility preservation in patients with haematological malignancies. STUDY FUNDING/COMPETING INTERESTS: This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

Reduced marine phytoplankton sulphur emissions in the Southern Ocean during the past seven glacials.

Marine biogenic sulphur affects Earth's radiation budget and may be an indicator of primary productivity in the Southern Ocean, which is closely related to atmospheric CO2 variability through the biological pump. Previous ice-core studies in Antarctica show little climate dependence of marine biogenic sulphur emissions and hence primary productivity, contradictory to marine sediment records. Here we present new 720,000-year ice core records from Dome Fuji in East Antarctica and show that a large portion of non-sea-salt sulphate, which was traditionally used as a proxy for marine biogenic sulphate, likely originates from terrestrial dust during glacials. By correcting for this, we make a revised calculation of biogenic sulphate and find that its flux is reduced in glacial periods. Our results suggest reduced dimethylsulphide emissions in the Antarctic Zone of the Southern Ocean during glacials and provide new evidence for the coupling between climate and the Southern Ocean sulphur cycle.

Greenland records of aerosol source and atmospheric lifetime changes from the Eemian to the Holocene.

The Northern Hemisphere experienced dramatic changes during the last glacial, featuring vast ice sheets and abrupt climate events, while high northern latitudes during the last interglacial (Eemian) were warmer than today. Here we use high-resolution aerosol records from the Greenland NEEM ice core to reconstruct the environmental alterations in aerosol source regions accompanying these changes. Separating source and transport effects, we find strongly reduced terrestrial biogenic emissions during glacial times reflecting net loss of vegetated area in North America. Rapid climate changes during the glacial have little effect on terrestrial biogenic aerosol emissions. A strong increase in terrestrial dust emissions during the coldest intervals indicates higher aridity and dust storm activity in East Asian deserts. Glacial sea salt aerosol emissions in the North Atlantic region increase only moderately (50%), likely due to sea ice expansion. Lower aerosol concentrations in Eemian ice compared to the Holocene are mainly due to shortened atmospheric residence time, while emissions changed little.

Pancreatic metaplasia in the gastro-achlorhydria in WTC-dfk rat, a potassium channel Kcnq1 mutant.

The WTC-deafness Kyoto (dfk) rat is a new mutant characterized by deafness and abnormal, imbalanced behavior. WTC-dfk rats carry an intragenic deletion at the Kcnq1 gene; KCNQ1 plays an important role in K(+) homeostasis, and the mutation of Kcnq1 causes a cardiac long QT syndrome in humans. Here, we studied stomach lesions in these WTC-dfk rats. The most characteristic pathologic feature in the stomach was the appearance of hypertrophic gastric glands in the stomach body. The hypertrophic cells had many eosinophilic granules in their cytoplasm, and these granules were stained red with Azan stain; stained positively for trypsinogen, amylase, and chymotrypsin; and did not stain positively for pepsinogen when using immunohistochemical analysis. These staining results suggested a metaplasia toward a pancreatic acinar cells. Extensive fibrosis was found in the bottom part of the mucosa of 34-week-old WTC-dfk rats, suggesting a progression of stomach lesions with aging. Although cells that were positive for proliferating cell nuclear antigen were restricted in the area of the glandular neck in WTC control rats, positive cells in WTC-dfk rats were scattered throughout the mucosa. The parietal cells in WTC-dfk rats were negative for KCNQ1 immunohistochemical analysis. These findings indicate that a deficiency in rat Kcnq1 provokes an abnormal proliferation and differentiation of gastric glandular cells.

Sparse and wavy hair: a new model for hypoplasia of hair follicle and mammary glands on rat chromosome 17.

Mutant animals in the skin and hair have been used to identify important genes in biomedical research. We describe a new mutant rat, sparse and wavy hair (swh), that spontaneously arose in a colony of inbred WTC rats. The mutant phenotype was characterized by sparse and wavy hair, which was most prominent at age 3-4 weeks, and was inherited in an autosomal recessive manner. The swh/swh rats showed impaired gain of body weight, and their hair follicles were reduced both in number and size, associated with hypoplasia of the sebaceous glands and the subcutaneous fat tissue. Female swh/swh rats were unable to suckle their offspring. Their mammary glands were hypoplastic, and differentiation of mammary epithelial and myoepithelial cells was impaired. Linkage analysis of 579 backcross rats localized the swh locus to a .35-cM region between D17Rat131 and D17Rat50 in the distal end of rat Chr 17. The swh locus spanned the 3.7-Mb genomic region where 24 genes have been mapped and corresponded to the centromere region of the mouse Chr 2 or the region of the human Chr 10p11.1-p14. None of the genes or loci described in mouse or human hair and skin diseases mapped to these regions. These findings suggest that the rat swh is a novel mutation associated with impaired development of the skin appendages, such as hair follicles, sebaceous glands, and mammary glands, and will provide an experimental model to clarify a gene and mechanisms for development of skin appendages.

Urinary bile alcohol profiles in healthy and cholestatic children.

BACKGROUND: Bile alcohols are normal constituents of urine. METHODS: To better understand bile alcohol profile in childhood, urinary specimens from 41 healthy children and 10 children with cholestasis, and 3 healthy adults, were analyzed by GLC and GC-MS. RESULTS: Five bile alcohols, 27-nor-5beta-cholestane-3alpha,7alpha,12alpha,24S,25R-pentol, 5beta-cholestane-3alpha,7alpha,12alpha,24S, 25-pentol, 5beta-cholestane-3alpha,7alpha,12alpha,24S,26-pentol, 5beta-cholestane-3alpha,7alpha, 12alpha,25,26-pentol, and 5beta-cholestane-3alpha,7alpha,12alpha,26,27-pentol were identified in all specimens. C(26)-Pentol was the most abundant constituent, constituting 29.5 to 65% of bile alcohols. Among healthy children (n=41), no significant relationship was seen between proportions of the C(26)-pentol and age, but older children (n=15, 6 to 14 years) showed a significantly greater mean percentage of the C(26)-pentol than young children (n=26, 0 to 5 years; 58.1+/-4.23% vs. 46.0+/-9.24%, p<0.001). In children with cholestatic liver diseases, the percentage of C(26)-pentol in urinary bile alcohols was significantly lower than age-matched controls. CONCLUSIONS: There is an increased composition of C(26)-pentol in older children and relatively decreased composition of C(26)-pentol in children with cholestatic liver diseases.

Effects of deoxycholic acid and its epimers on lipid peroxidation in isolated rat hepatocytes.

We studied the effects of deoxycholic acid and its three epimers with beta-hydroxyl groups (3alpha,12beta-, 3beta,12alpha-, and 3beta,12beta-dihydroxy-5beta-cholan-24-oic acids), which were hydrophilic and less cytotoxic, on lipid peroxidation to elucidate the relationship between structural features of bile acids and their effect on lipid peroxidation. Taurodeoxycholate markedly increased the production of thiobarbituric acid-reactive substances, end products of lipid peroxidation, in isolated rat hepatocytes, whereas epimers of taurodeoxycholate did not. Deoxycholic acid inhibited mitochondrial NADH dehydrogenase and NADH:ferricytochrome c oxidoreductase activities, leading to free radical generation, whereas epimers of deoxycholic acid had no effect on mitochondrial enzymes. These findings suggested that hydrophobic bile acids cause lipid peroxidation by impairment of mitochondrial function, leading to the generation of free radicals; and epimerization of alpha-hydroxyl groups in the steroid nucleus to beta-hydroxyl groups results in a decrease of the toxic effects of deoxycholic acid on lipid peroxidation.

Hepatic uptake and gene expression mechanisms following intravenous administration of plasmid DNA by conventional and hydrodynamics-based procedures.

Hepatic uptake and gene expression mechanisms following intravenous administration of naked plasmid DNA (pDNA) by conventional and hydrodynamics-based procedures were studied in mice. After conventional (normal) intravenous injection, (32)P-labeled pDNA was rapidly eliminated from the circulation and predominantly taken up by the liver nonparenchymal cells while no significant gene expression was observed in this organ. The hepatic uptake process was saturable. Involvement of a specific mechanism was demonstrated since the hepatic uptake of [(32)P]pDNA was dramatically inhibited by cold pDNA, calf thymus DNA, and some polyanions [polyinosinic acid (poly I), dextran sulfate], but not by others (polycytidylic acid, chondroitin sulfate). The liver endothelial cells appeared to be a major contributor because gadolinium chloride (GdCl(3))-induced Kupffer cell blockade did not affect the hepatic uptake. After intravenous injection of naked pDNA with a large volume of saline at a high velocity (hydrodynamics-based procedure), the apparent hepatic uptake profile was similar to that after normal injection. The hepatic uptake was not inhibited by prior administration of polyanions, including poly I, dextran sulfate, and heparin. The hydrodynamics-based procedure resulted in marked gene expression in the liver, which was not inhibited by prior administration of polyanions or GdCl(3) treatment. These results indicate that pDNA uptake is a nonspecific process. This hypothesis was supported by the finding that significant hepatic uptake of bovine serum albumin and immunoglobulin G was observed after the hydrodynamics-based procedure.

Hypocholesterolemic effect of bile acid sulfonate analogs in hamsters.

We studied the effects of bile acid sulfonate analogs, namely, 3alpha,7alpha,12alpha-trihydroxy-5beta-cholane-24-sulfonate (C-sul), 3alpha,7alpha-dihydroxy-5beta-cholane-24-sulfonate (CDC-sul), and 3alpha,7beta-dihydroxy-5beta-cholane-24-sulfonate (UDC-sul), on serum and liver cholesterol levels, cholesterol 7alpha-hydroxylase activity, and biliary bile acid composition in hamsters fed cholesterol. Of the three analogs studied, UDC-sul slightly but significantly decreased free, esterified, and total cholesterol concentrations in the serum. UDC-sul and CDC-sul reduced liver total cholesterol levels by 25% and 18%, respectively, particularly in the esterified cholesterol fraction. Analysis of biliary bile acids showed the presence of the administered analogs, indicating that sulfonate analogs efficiently participate in enterohepatic cycling. The proportion of cholic acid was increased in all groups fed sulfonate analogs, but the ratio of glycine to taurine conjugated bile acids (G/T) was elevated only in UDC-sul feeding hamsters. There was no significant change in cholesterol 7alpha-hydroxylase activity in hamsters fed C-sul or CDC-sul, while UDC-sul slightly stimulated the enzyme activity compared to the control. The UDC-sul induced decrease in serum and liver cholesterol concentrations may be secondary to enhanced bile acid synthesis. This is supported by the increased cholesterol 7alpha-hydroxylase activity and elevated G/T ratio in biliary bile acids observed following UDC-sul administration.

Attractin/mahogany/zitter plays a critical role in myelination of the central nervous system.

The rat zitter (zi) mutation induces hypomyelination and vacuolation in the central nervous system (CNS), which result in early-onset tremor and progressive flaccid paresis. By positional cloning, we found a marked decrease in Attractin (Atrn) mRNA in the brain of the zi/zi rat and identified zi as an 8-bp deletion at a splice donor site of Atrn. Atrn has been known to play multiple roles in regulating physiological processes that are involved in monocyte-T cell interaction, agouti-related hair pigmentation, and control of energy homeostasis. Rat Atrn gene encoded two isoforms, a secreted and a membrane form, as a result of alternative splicing. The zi mutation at the Atrn locus darkened coat color when introduced into agouti rats, as also described in mahogany (mg) mice, carrying the homozygous mutation at the Atrn locus. Transgenic rescue experiments showed that the membrane-type Atrn complemented both neurological alteration and abnormal pigmentation in zi/zi rats, but that the secreted-type Atrn complemented neither mutant phenotype. Furthermore, we discovered that mg mice exhibited hypomyelination and vacuolation in the CNS associated with body tremor. We conclude from these results that the membrane Atrn has a critical role in normal myelination in the CNS and would provide insights into the physiology of myelination as well as the etiology of myelin diseases.

Structural and biosynthetic studies of a principal bile alcohol, 27-nor-5beta-cholestane-3alpha,7alpha,12alpha,24,25-pentol, in human urine.

The stereochemistry at C-24 and C-25 of 27-nor-5beta-cholestane-3alpha,7alpha,12alpha,24 ,25-pentol, a principal bile alcohol in human urine, and its biosynthesis are studied. Four stereoisomers of the C(26)-24,25-pentols were synthesized by reduction with LiAlH(4) of the corresponding epoxides prepared from (24S)- or (24R)-27-nor-5beta-cholest-25-ene-3alpha, 7alpha,12alpha,24-tetrol. The stereochemistries at C-25 were deduced by comparison of the C(26)-24,25-pentols with the oxidation products of (24Z)-27-nor-5beta-cholest-24-ene-3alpha,7alpha, 12alpha-triol with osmium tetraoxide. On the basis of this assignment, the principal bile alcohol excreted into human and rat urine was determined to be (24S,25R)-27-nor-5beta-cholestane-3alpha,7alpha, 12alpha,24,25-pentol, accompanied by a lesser amount of (24R, 25R)-isomer. To elucidate the biosynthesis of the C(26)-24,25-pentol, a putative intermediate, 3alpha,7alpha, 12alpha-trihydroxy-27-nor-5beta-cholestan-24-one, derived from 3alpha,7alpha, 12alpha-trihydroxy-24-oxo-5beta-cholestanoic acid by decarboxylation during the side-chain oxidation of 3alpha,7alpha, 12alpha-trihydroxy-5beta-cholestanoic acid, was incubated with rat liver homogenates. The 24-oxo-bile alcohol could be efficiently reduced to yield mainly (24R)-27-nor-5beta-cholestane-3alpha,7alpha, 12alpha,24-tetrol. If a 25R-hydroxylation of the latter steroid occurs, it should lead to formation of (24S,25R)-C(26)-24,25-pentol. Now it has appeared that a major bile alcohol excreted into human urine is (24S,25R)-27-nor-5beta-cholestane-3alpha,7alpha, 12alpha, 24, 25-pentol, which might be derived from 3alpha,7alpha, 12alpha-trihydroxy-27-nor-5beta-cholestan-24-one via (24R)-27-nor-5beta-cholestane-3alpha, 7alpha,12alpha,24-tetrol.

Bile acids in porcine fetal bile.

A study of the biliary bile acid composition in porcine fetus compared with that of the adult pig is described. Biles, collected during gestation (weeks 4, 15 to 17 and at birth), aged six months and two years old, were analyzed by gas-liquid chromatography and capillary GC-MS. Bile acids were separated into different conjugate groups by chromatography on the lipophilic anion exchange gel, piperidinohydroxypropyl Sephadex LH-20. All and one fourth of the total bile acids in the bile of weeks 4 and 15 of gestation, respectively, were present as unconjugated form, however, only a trace of unconjugated bile acids was present in bile of late gestation, the young and the adult pigs. The ratio of glycine/taurine (G/T) conjugates in the conjugated fraction of the fetal bile at 15 weeks gestation was less than 1, which markedly contrasted with the conjugation pattern for adult bile where the ratio of G/T conjugates was approximately more than 9. The predominant acids identified in porcine fetal bile of the 4 weeks gestation were cholic acid (3alpha,7alpha,12alpha-trihydroxy-5beta-chola n-24-oic acid) and chenodeoxycholic acid (3alpha,7alpha -dihydroxy-5beta-cholan-24-oic acid). However, cholic acid in late gestation, young, and adult bile was the smallest component, whereas chenodeoxycholic acid was still the major constituent of these biles. The presence of small but valuable amounts of allocholic acid (3alpha,7alpha,12alpha-trihydroxy-5alpha-chol an-24-oic acid) and cholic acid in early gestation suggested the presence of 12alpha-hydroxylase activity of steroid nucleus in fetal liver. Considerable amounts of glycine-conjugated hyodeoxycholic acid were found in the bile of the gestation periods, suggesting the placental transfer of this bile acid from maternal circulation.

Expression of the SART3 tumor-rejection antigen in brain tumors and induction of cytotoxic T lymphocytes by its peptides.

The authors recently reported on the SART3 tumor-rejection antigen, which possesses epitopes that can induce cytotoxic T lymphocytes (CTLs) in patients with epithelial cancer. To explore a new modality for treatment of patients with brain tumors, this study investigated the expression of the SART3 antigen in patients with brain tumors and the ability of SART3 peptides to induce CTLs from peripheral blood mononuclear cells (PBMCs) of these patients. The SART3 antigen was detected in the cytoplasmic fraction of all 18 glioma cell lines examined and in the majority (31 of 34; 91%) of brain tumor tissues irrespective of their histologies. It was also expressed in the nuclear fraction of all 18 glioma cell lines and in the majority (26 of 34; 76%) of brain tumor tissues. In contrast, the SART3 was not expressed in nontumorous brain tissues. Cytotoxic T lymphocytes were induced in patients with glioma by stimulation with two epitope peptides of SART3. These CTLs could eliminate glioma cells in a HLA-A24-restricted manner. Therefore, the SART3 peptides may be appropriate molecules for use in peptide-based specific immunotherapy of HLA-A24+ patients with brain tumors.

Accumulation of N-acetyl-L-aspartate in the brain of the tremor rat, a mutant exhibiting absence-like seizure and spongiform degeneration in the central nervous system.

The tremor rat is a mutant that exhibits absence-like seizure and spongiform degeneration in the CNS. By positional cloning, a genomic deletion was found within the critical region in which the aspartoacylase gene is located. Accordingly, no aspartoacylase expression was detected in any of the tissues examined, and abnormal accumulation of N-acetyl-L-aspartate (NAA) was shown in the mutant brain, in correlation with the severity of the vacuole formation. Therefore, the tremor rat may be regarded as a suitable animal model of human Canavan disease, characterized by spongy leukodystrophy that is caused by aspartoacylase deficiency. Interestingly, direct injection of NAA into normal rat cerebroventricle induced 4- to 10-Hz polyspikes or spikewave-like complexes in cortical and hippocampal EEG, concomitantly with behavior characterized by sudden immobility and staring. These results suggested that accumulated NAA in the CNS would induce neuroexcitation and neurodegeneration directly or indirectly.

Asymmetric reduction of ethyl 2-methyl e-oxobutanoate by fungi.

Seven fungi, which are found to reduce ethyl 3-oxobutanoate in high yields, were tested for their reducing ability for ethyl 2-methyl 3-oxobutanoate. We obtained some interesting findings. In particular, Penicillium purpurogenum reduced ethyl 2-methyl 3-oxobutanoate to the corresponding alcohols with the diastereomer (anti/syn) ratio of 93/7 with the enantiomeric excess of anti-(2S,3S)- and syn-(2S,3R)- hydroxy esters of 90 and >99 ee%, respectively.

Enhancing effect of 5 alpha-cyprinol sulfate on mucosal membrane permeability to sodium ampicillin in rats.

Effect of 5 alpha-cyprinol sulfate, a bile alcohol sulfate specific to carp bile, on rectal membrane permeability to sodium ampicillin (AMP Na) was examined in rats. AMP Na is not easily absorbed through rat rectal membrane without aid. 5 alpha-Cyprinol sulfate significantly enhanced the rectal membrane permeability to AMP Na even at a low concentration (6.25 mM), though sodium taurocholate needed a higher concentration (25 mM). Co-administration of phosphatidylcholine significantly suppressed the enhancing action of both sodium taurocholate and 5 alpha-cyprinol sulfate. On the other hand, calcium ion did not suppress the action of 5 alpha-cyprinol sulfate, although it did clearly suppress the action of sodium taurocholate. In conclusion, 5 alpha-cyprinol sulfate was found to have a potent enhancing effect on mucosal membrane permeability to water-soluble compounds. The enhancing mechanism of 5 alpha-cyprinol sulfate appeared to be different from that of sodium taurocholate.