Universal newborn screening: A roadmap for action.

Newborn screening (NBS) prevents morbidity and mortality by screening babies for selected disorders in the first days of life so that early diagnosis and treatment can be initiated. Congenital disorders impact an estimated 8 million or 6% of annual births worldwide, and of the top five that contribute 25% to the global burden of these disorders, three can be identified and managed by NBS. There are determined pockets of activity in Latin America, Sub-Saharan Africa, and the Asia Pacific region, where partnerships among government, non-governmental organizations, academia, the private sector and civil society are developing novel NBS programs that are both saving lives and preventing disability in those who survive.

Mucosa-preferential DNA adduct formation by 2-amino-3-methylimidazo-[4,5-f]quinoline in the rat colonic wall.

The mechanism of mucosa-specific formation of DNA adducts, which was found recently in human intestines, was studied in male F344 rats treated with 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). There are three conceivable pathways for p.o. administered IQ to reach the target colonic mucosal cells: pathway 1, through the digestive canal which exposes from the lumenal direction; pathway 2, following enterohepatic circulation re-expose from the lumenal direction; and pathway 3, exposure via blood circulation. To investigate these possible pathways, the following surgical procedures were performed: (a) portal catheterization for IQ administration to eliminate pathway 1 and (b) choledochal catheterization for bile drainage to eliminate pathway 2. When both procedures are combined, only pathway 3 is active. Four types of IQ-DNA adducts were commonly observed in the colons of all experimental groups, with no qualitative difference between the mucosal and muscular layers. When IQ-HCl was administered by p.o. gavage at a dose of 100 mumol/kg body weight, approximately 70% of the IQ-DNA adducts in the colonic mucosa (13.1 +/- 4.3 adducts/10(7) nucleotides) was induced through pathway 1. Pathway 3 induced the remaining 30% of mucosal adducts, producing equal adduct levels in both layers. Pathway 2 did not work for adduct formation. The DNA adduct formation was unaffected in the presence of intestinal flora, indicating that detoxified IQ does not reactivate by floral enzymes. In conclusion, mucosa-specific DNA adduct formation in the colon is caused most likely by the absorption of carcinogens through the lumen.

Exploring individual differences in task switching: Persistence and other personality traits related to anterior cingulate cortex function.

Anterior cingulate cortex (ACC) is involved in cognitive control and decision-making but its precise function is still highly debated. Based on evidence from lesion, neurophysiological, and neuroimaging studies, we have recently proposed a critical role for ACC in motivating extended behaviors according to learned task values (Holroyd and Yeung, 2012). Computational simulations based on this theory suggest a hierarchical mechanism in which a caudal division of ACC selects and applies control over task execution, and a rostral division of ACC facilitates switches between tasks according to a higher task strategy (Holroyd and McClure, 2015). This theoretical framework suggests that ACC may contribute to personality traits related to persistence and reward sensitivity (Holroyd and Umemoto, 2016). To explore this possibility, we carried out a voluntary task switching experiment in which on each trial participants freely chose one of two tasks to perform, under the condition that they try to select the tasks "at random" and equally often. The participants also completed several questionnaires that assessed personality trait related to persistence, apathy, anhedonia, and rumination, in addition to the Big 5 personality inventory. Among other findings, we observed greater compliance with task instructions by persistent individuals, as manifested by a greater facility with switching between tasks, which is suggestive of increased engagement of rostral ACC.

Analysis system of submicron particle tracks in the fine-grained nuclear emulsion by a combination of hard x-ray and optical microscopy.

Analyses of nuclear emulsion detectors that can detect and identify charged particles or radiation as tracks have typically utilized optical microscope systems because the targets have lengths from several µm to more than 1000 µm. For recent new nuclear emulsion detectors that can detect tracks of submicron length or less, the current readout systems are insufficient due to their poor resolution. In this study, we developed a new system and method using an optical microscope system for rough candidate selection and the hard X-ray microscope system at SPring-8 for high-precision analysis with a resolution of better than 70 nm resolution. Furthermore, we demonstrated the analysis of submicron-length tracks with a matching efficiency of more than 99% and position accuracy of better than 5 µm. This system is now running semi-automatically.

The effect of the crp genotypes on the transformation efficiency in Escherichia coli.

We have found that a significant difference exists in transformation efficiency between the crp+/crp- isogenic pair of strains of Escherichia coli, with the efficiency being much higher in crp- than in crp+. The ratio of transformation efficiency between crp+ and crp- strains depends very little on the plasmid size. This observation suggests that the difference of the transformation efficiency is due to mechanisms other than a crp-regulated endonuclease. The crp gene is one of the first specific genes that have been shown to affect transformation efficiency.

Nested deletions from a fixed site as an aid to nucleotide sequencing: an in vitro system using Tn3 transposase.

We have previously constructed a cloning/sequencing vector, with an in vivo system capable of creating nested deletions from the end of transposon Tn3, which is useful for sequencing large DNAs. Here we report an in vitro system which uses an ammonium sulfate fraction of extract from E. coli cells harboring a Tn3 transposase overproducer plasmid to generate nested deletions. A key feature of the procedure is exhaustive digestion of the reaction products with a restriction enzyme that cleaves only between the Tn3 "right" terminus and the cloned fragment. This step reduces the noise level due to mechanisms other than deletions from the Tn3 terminus, and facilitates detection and isolation of the desired deletion products. This system enables us to save at least 2 days' time when obtaining the necessary deletions compared with the in vivo system.

Effects of dietary bile acids on formation of azoxymethane-induced aberrant crypt foci in F344 rats.

The present study has demonstrated the influence of bile acids (BAs) on the development and growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF). Male F344 rats were treated with two doses of AOM (15 mg/kg) at 7 days apart and fed either basal MF or MF plus 0.4% of cholic (CA), deoxycholic (DCA), chenodeoxycholic (CDCA), lithocholic (LCA) and ursodeoxycholic (UDCA) acid mixed diets for 8 weeks after the first AOM dose. The mean number of ACF/colon of the rats fed CA, DCA, CDCA and LCA were higher than that of MF-fed group and the differences were statistically significant (P < 0.005). But the mean number of ACFs/colon was significantly (P < 0.005) lower in UDCA diet-fed rats compared to MF. UDCA-fed rats also showed a significant decrease in average crypt multiplicity (number of crypts/focus) of ACF compared to MF alone. The mean number of ACF with > or =5 crypts was about 2.5-3.7 times higher in case of CA, DCA, CDCA and LCA and about 8.2 times lower in UDCA compared to the control MF diet group. In a parallel study, feeding for 18 weeks of the same BAs mixed diets without AOM administration did not significantly induce ACF. Therefore, these data suggest that dietary BAs by themselves do not induce ACF in F344 rats but enhance or, in the case of UDCA, suppress the development and growth of AOM-induced ACF.

Effect of bile acids on formation of azoxymethane-induced aberrant crypt foci in colostomized F344 rat colon.

The effect of bile acids on the formation of azoxymethane induced aberrant crypt foci (ACF) was investigated using the fecal stream-excluded colons of colostomized F344 rats. The excluded colon was irrigated with saline or bile acids (1 mg/0.5 ml per day, 5 days/week) for 4 weeks. The mean numbers of ACF per colon in rats given cholic acid, deoxycholic acid (DCA), chenodeoxycholic acid (CDCA), lithocholic acid, and ursodeoxycholic acid (UDCA) were 160.8, 118.2, 227.8, 150.7 and 87.3, respectively, while that of the control was 174.0. The number of ACF was significantly larger in CDCA, but smaller in UDCA and DCA-treated rats than the control (P<0.01). DCA did not induce apoptosis in the colon under the present conditions.

Metabolic aspects of pyrolysis mutagens in food.

The first step in metabolic activation of mutagenic and carcinogenic heterocyclic amines has been elucidated to be N-hydroxylation by cytochrome P-448. N-Hydroxyamino compounds are further activated to form N-O-acyl derivatives that readily react with DNA. The adducts between the metabolites of Trp-P-2 and Glu-P-1 and DNA were shown to have a C8-guanylamino structure. In the case of Glu-P-1, modification of guanine in GC clusters occurred preferentially. Glutathione transferases and myeloperoxidase were shown to inactivate some heterocyclic amines or their active metabolites. Hemin and fatty acids bind to and inactivate them. Fibers and other factors from vegetables also work to inactivate heterocyclic amines. Nitrite at low pH also degraded some heterocyclic amines, but those with an imidazole moiety were resistant. Glu-P-1 induced intestinal tumors in a high incidence when fed orally to rats. When 14C-Glu-P-1 was administered by gavage into rats about 50% and 35% were excreted into feces and urine, respectively, within 24 hr. When the bile was collected, around 60% of radioactivity was excreted into it within 24 hr. In the bile, N-acetyl-Glu-P-1 was identified as one of the metabolites of Glu-P-1. It showed a mutagenic activity of about one fourth that of Glu-P-1 with S9 mix. Some radioactivity was also detected in the blood. At 24 hr after administration, most of the radioactivity was found to be bound to erythrocyte beta-globins and serum proteins including albumin.

The molecular basis of the instability of a crp- mutation in Escherichia coli.

We have described a rapid spontaneous conversion in the stationary phase of Escherichia coli strain DOO (crp-) cells as a whole population to crp+ state (Sugino and Morita, 1994). In this paper we have tried to elucidate the molecular basis of this unidirectional conversion by cloning and sequencing of the crp gene in their crp+ and crp- states. We have found that in the original crp- strain, an IS2 element has been inserted between its original promoter and the coding region of the crp gene in the so-called orientation II (Ahmed et al., 1981), accompanied by an 11 bp deletion. Unexpectedly, the crp+ "revertants" derived from the crp- mutant had no difference in sequence from the crp-, either in the coding or the regulatory region. This suggests that a change at another locus, such that this change somehow activates the expression of the crp gene to the level of a normal crp+, is responsible for the apparent reversion from crp- to crp+.

DNA adduct formation by 2-amino-3-methylimidazo [4,5-f] quinoline (IQ) in rat colon.

A food-born carcinogen, 2-amino-3-methylimidazo [4,5-f] quinoline (IQ) induces cancer in the rat colon. The mechanism for colonic DNA adduct formation leading to cancer by IQ was studied using a colostomized F344 rat model. In this model, the transverse colon of the rat was colostomized, which produced a fecal stream-positive proximal colon and a negative distal colon were produced. When IQ (50 mg/kg) was administered into the distal colon of the colostomized rats (n = 5), the ratio of the DNA adduct level of the distal colonic mucosa to the paired muscular layer 24 hr after dosage was 2.02, whereas that was 1.51 and 1.37 when IQ was administered into the stomach (n = 6) and the vein (n = 5), respectively. This suggested that luminal exposure of IQ induced DNA adduct formation. Since IQ (an amine form) has no reactivity toward DNA, these findings suggested that IQ was immediately activated in the absorbed mucosal cells and reacted with DNA. However, most of the IQ absorbed was metabolically activated in the liver, distributed by blood circulation, and formed DNA adducts in the colonic mucosa and muscular layer.

Non-enzymatic glutathione conjugation of 2-nitroso-6-methyldipyrido [1,2-a: 3',2'-d] imidazole (NO-Glu-P-1) in vitro: N-hydroxy-sulfonamide, a new binding form of arylnitroso compounds and thiols.

In order to study the possible detoxification mechanisms of the carcinogenic arylamine, 2-amino-6-methyldipyrido[1,2-a: 3',2'-d]imidazole (Glu-P-1), the in vitro non-enzymatic reaction of 2-nitroso-6-methyldipyrido[1,2-a: 3',2'-d]imidazole (NO-Glu-P-1) with reduced glutathione (GSH) was examined at pH 7.4 under both aerobic and anaerobic conditions. Two GSH-arylamine adducts were isolated and found to contain the Glu-P-1 and GSH moieties in a 1:1 molar ratio via an N-S linkage. Their structures were assigned as sulfinamide (-NH-SO-) and N-hydroxy-sulfonamide (-N(OH)-SO2-) by their behaviour under acidic and basic conditions and by UV-VIS, 1H-NMR, infrared and mass spectrometries. Also, a N-hydroxy-sulfonamide adduct was produced when NO-Glu-P-1 and cysteine were reacted at pH 7.4. The N-hydroxy-sulfonamide structure is a new binding form between arylnitroso compounds and thiols. The formation of these adducts may also take place in vivo as a detoxification of toxic arylamines since GSH is abundant in organs such as liver or kidney.

N-acetyl derivative as the major active metabolite of 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole in rat bile.

2-Amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1) is a mutagen and carcinogen isolated from a glutamic acid pyrolysate. When this 14C-labeled compound was administered to male F344 rats at a dose of 0.3 mCi (20.8 mg)/kg b.w., 70% of the radioactivity was excreted into the bile in 24 h. On HPLC analysis of this bile, several metabolites of Glu-P-1 were found with unmetabolized Glu-P-1. One of the mutagenic metabolites was identified as N-acetyl-Glu-P-1. This metabolite had a specific mutagenic activity of about one quarter of that of Glu-P-1 and its amount in the bile corresponded to a few percent of the dose of Glu-P-1 administered.

DNA adduct formation by hormonal steroids in vitro.

We examined the binding of various steroid hormones to DNA in vitro by means of 32P-postlabeling. Seventeen steroid hormones and cholesterol (CS) were incubated with human liver DNA at 37 degrees C for 1 h under aerobic conditions in the absence of catalysis. The reaction mixtures were analyzed by the nuclease P-1 version of 32P-postlabeling. The results showed that cortexolone (CX), prednisolone (PS), cortisone (CN), cortisol (CL), tetrahydrocortisol (TC), corticosterone (CC), 11-deoxycorticosterone (DC), dexamethasone (DX), dihydrocortisol (DL), and aldosterone (AL) covalently bound with DNA. However, progesterone (PG), 17 alpha-hydroxyprogesterone (HG), estrone (E1), estradiol (E2), estriol (E3), testosterone (TS), cortol (CR) and the original compound for biosynthesis, CS, did not form adducts. In absence of DNA, the steroids themselves did not give rise to any spot on TLC under the same conditions. The dose-responses of DNA binding by DC, DL, CC, CL and CN were linear. The relative adduct labeling of reactive steroids at a concentration of 2 mM were as follows: 68.8 (CX), 53.2 (PS), 39.6 (CN), 29.9 (CL), 20.9 (TC), 12.9 (CC), 12.3 (DC), 7.5 (DX), 4.7 (DL), 1.2 (AL) adducts per 10(8) nucleotides. Reactive and nonreactive steroids were distinguishable by the presence or absence of the carbonyl group (-CO-CH2OH) at carbon seventeen (C17) of the cholesterol skeleton. This implies that the electrophilic carbonyl or a neighboring group perhaps involved in the formation of covalent bond with DNA. To investigate the nature of target base(s) of these DNA reactive steroids, mononucleotides of all four bases of DNA were reacted with CN, CL, CC and cochromatographed with the obtained spots of DNA reactions. The results of which stated that these steroids and guanine reaction gave the same spots as observed in DNA reaction, indicating guanine is the main target of these DNA reactive steroids. Hep G2 human hepatocellular carcinoma cells were used as an alternative model. Although nine steroids (CL, DL, TC, PS, DX, PG, E2, TX, CR) did not react with intracellular DNA under our experimental conditions, our findings suggested that some hormonal steroids can form covalent DNA adducts in vivo.

Activation of mutagenic and carcinogenic heterocyclic amines by S-9 from the liver of a rhesus monkey.

The mutagenicity of a series of heterocyclic amines isolated from various cooked foods and from pyrolysates of amino acids and protein was assayed in Salmonella typhimurium TA98 in the presence of an S-9 fraction prepared from the liver of an untreated male rhesus monkey (Macaca mulatta). All the compounds showed mutagenicity, which ranged from 1 to 2500 revertants/mug chemical/mg S-9 protein. 2-Amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) showed the highest specific mutagenic activity, followed by 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (7,8-DiMeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline 4,8-DiMeIQx, 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1) and 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAalphaC). 2-Amino-9H-pyrido[2,3-b]indole (AalphaC) and 2-aminodipyrido[1,2-a:3',2'-d]imidazole (Glu-P-2) also showed definite but weak mutagenicity. When compared with previously reported data, these specific mutagenic activities were very close to those of some heterocyclic amines assayed with the S-9 of human liver, slightly lower than those determined with the S-9 of untreated rat liver and much lower than those determined with S-9 from the liver of the untreated hamster or mouse. Most of the heterocyclic amines tested in this experiment have shown carcinogenicity in mice and rats. The experimental results now reported suggest the possible carcinogenicity of these heterocyclic amines in primates as well, including humans.

Effects of bile acids on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine-induced aberrant crypt foci and DNA adduct formation in the rat colon.

The effects of deoxycholic acid (DCA) and ursodeoxycholic acid (UDCA) on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced aberrant crypt foci (ACF) in the rat colon were examined. The effect of these bile acids on DNA adduct formation by PhIP in the colon was then analyzed, since the main action of PhIP is the formation of DNA adducts and subsequent gene mutations. For the ACF study, male F344 rats were administered PhIP-HCl (75 mg/kg, 10 doses) by gavage, and a diet containing bile acid (0.4% DCA or UDCA) was provided from 3 days before the first dose of PhIP for 8 weeks. The mean number of ACF per colon of DCA, UDCA and controls were 9.9, 2.4 and 5.5, respectively. The ACF number was significantly increased by DCA and decreased by UDCA (P<0.001). To examine the effect of bile acids on DNA adduct formation, male F344 rats were fed a diet supplemented with bile acids (0.1 or 0.4% of DCA and UDCA) 7 days prior to the PhIP administration. All rats were administered a single dose of PhIP-HCl (50 mg/kg) by gavage and sacrificed 48 hours later. DNA adduct levels of the 0.1% UDCA, 0.1% DCA and controls were 2.93 (adducts/10(7) nucleotides), 2.65 and 1.10, respectively. Those of 0.4% UDCA, 0.4% DCA and controls were 1.64, 1.30 and 1.00, respectively. The PhIP-DNA adduct level was significantly increased by administration of 0.1% UDCA, 0.1% DCA (P<0.05) and 0.4% UDCA (P<0.01). The increasing effect of both DCA and UDCA on PhIP-induced DNA adduct formation was unexpected, and was not directly associated with ACF formation.

[Effect of preoperative intra-arterial infusion of adriamycin on locally advanced breast cancer].

The effect of adriamycin (ADM) infused intraarterially as a preoperative procedure was analyzed retrospectively in 15 patients with primary advanced breast cancer. A high clinical response rate (CR+ PR) of 73% (11/15) was obtained by the treatment, and also remarkable degenerative changes of tumor cells were histologically noted in 10 out of 15 surgical specimens (67%). A correlation between the dose of ADM infused and the rate of tumor regression was observed. A significantly higher concentration of ADM was detected in metastatic lymph nodes and tumors obtained 3-4 weeks after intra-arterial infusion of ADM than that in normal mammary gland. As for side effects, alopecia, leukocytopenia, anorexia, nausea and vomiting occurred at high frequencies. The side effects due to this treatment were considered to be tolerable. Prognostically, a good survival rate was not observed using preoperative treatment with intra-arterial ADM infusion.

[A case of umbilical polyp with aberrant pancreas and small intestinal mucosa--analysis of cases of umbilical polyp reported in Japan].

We report a case of a 60 year-old man with an umbilical polyp composed of the aberrant pancreas and small intestinal mucosa. This is an extremely rare lesion which originates in remnants of omphalomesenteric duct and is usually diagnosed in the infant period. Microscopic examination disclosed the aberrant pancreas with exocrine glands and ducts, but no islets of Langerhans. The above findings suggested that the pancreas might have been HEINRICH II in type.

[Preservation of the nipple and areola for breast cancer--histopathological study on cancerous involvement of the nipple and areola].

In 141 mastectomy specimens, performed for invasive or non-invasive carcinomas, histopathologic study was performed to assess the extent of nipple-areola involvement by the tumor. In this study, patients were excluded when 1) the tumor was located beneath the areola, 2) nipple and/or areola abnormalities were clinically present. Tumor involvement of the nipple and/or areola was found in 44 of 141 specimens (31%), with intraductal growth in 36 (82%) of 44, stromal invasion in 3 (7%) and ductal & stromal invasion in 5 (11%). Analysis of nipple-areolar involvement with consideration of the different variables indicates that it occurred in association with tumor size, tumor-areola distance and histological type. Such information provides clinically relevant guide lines in decision making for limited breast surgery.