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Binuclear Pd(II) and Pt(II) complexes supported by rac-dpmppm (bis[(diphenylphosphinomethyl)phenylphosphino]methane) in a triply-bridged Z-form, [M2Cl4(rac-dpmppm)] (M = Pd (3a), Pt (3b)), readily reacted with 2,6-xylyl isocyanide (XylNC) in the presence of NH4PF6 to afford [M2Cl2(rac-dpmppm)(XylNC)2](PF6)2 (M = Pd (4a), Pt (4b)), in which each metal center accommodates one isocyanide ligand at the trans position to the inner P atom of dpmppm. Similarly, treatment of 3a and 3b with axially chiral (R/S)-1,1'-binaphthyl-2,2'-bisisocyanide (rac-Binac) in the presence of NH4OTf gave cyclic tetranuclear complexes, [{M2Cl2(rac-dpmppm)(rac-Binac)}2](OTf)4 (M = Pd (5), Pt (8)), where two {M2Cl2(rac-dpmppm)}2+ fragments are connected by two rac-Binac ligands through chirality sorting of (R*,R*)-dpmppm and (R*)-Binac. Complex 5 could be transformed into the halide exchanged tetranuclear complexes, [{Pd2X2(rac-dpmppm)(rac-Binac)}2](OTf)4 (X = Br (6), I (7)), to show that the rectangular arrangement of four Pd(II) ions is elongated by repulsive interaction between halide ligands. By using (R)- and (S)-Binac, enantiopure Pd4 complexes, [{Pd2Cl2((R*,R*)-dpmppm)((R*)-Binac)}2](OTf)4 (5RR/R and 5SS/S), were successfully isolated as pure crystalline forms, from which enantiopure (R,R)- and (S,S)-dpmppm were obtained by treatment with NaCN aqueous solution. Namely, optical resolution of rac-dpmppm was established through the tetranuclear Pd complexes, which is the first example for methylene-bridged polyphosphines, R2P(CH2PR)nCH2PR2 (n > 0). Furthermore, chiral octapalladium chains, [Pd8((R*,R*)-dpmppm)4(N≡CCH3)2](BF4)4 (2RR and 2SS), were synthesized by reacting enantiopure P-chiral dpmppm with [Pd2(CH3CN)6](BF4)2 and [Pd2(dba)3]·C6H6 and were characterized by spectroscopic and X-ray crystallographic analyses, to determine the absolute configurational structures. The Pd8 chains are the longest enantiopure chiral single-metal-atom chains structurally characterized, thus far, and the electronic structures were examined on the basis of DFT calculations of 2RR.

A series of tetragold(I) complexes supported by tetraphosphine ligands, meso- and rac-bis[(diphenylphosphinomethyl)phenylphosphino]methane (meso- and rac-dpmppm) were synthesized and characterized to show that the tetranuclear Au(I) alignment varies depending on syn- and anti-arrangements of the two dpmppm ligands with respect to the metal chain. The structures of syn-[Au4 (meso-dpmppm)2X]X'3 (X = Cl; X' = Cl (4 a), PF6 (4 b), BF4 (4 c)) and syn-[Au4 (meso-dpmppm)2]X4 (X = PF6 (4 d), BF4 (4 e), TfO (4 f); TfO = triflate) involved a bent tetragold(I) core with a counter anion X incorporated into the bent pocket. Complexes anti-[Au4 (meso-dpmppm)2]X4 (X = PF6 (5 d), BF4 (5 e), TfO (5 f)) contain a linearly ordered Au4 string and complexes syn-[Au4 (rac-dpmppm)2X2]X'2 (X = Cl, X' = Cl (6 a), PF6 (6 b), BF4 (6 c)) and syn-[Au4 (rac-dpmppm)2]X4 (X = PF6 (6 d), BF4 (6 e), TfO (6 f)) consist of a zigzag tetragold(I) chain supported by the two syn-arranged rac-dpmppm ligands. Complexes 4 d-f, 5 d-f, and 6 d-f with non-coordinative large anions are strongly luminescent in the solid state (λmax = 475-515 nm, Φ = 0.67-0.85) and in acetonitrile (λmax = 491-520 nm, Φ = 0.33-0.97); the emission was assigned to phosphorescence from (3) [dσ*σ*σ* pσσσ] excited state of the Au4 centers on the basis of DFT calculations as well as the long lifetime (a few μs). The emission energy is predominantly determined by the HOMO and LUMO characters of the Au4 centers, which depend on the bent (4), linear (5), and zigzag (6) alignments. The strong emissions in acetonitrile were quenched by chloride anions through simultaneous dynamic and static quenching processes, in which static binding of chloride ions to the Au4 excited species should be the most effective. The present study demonstrates that the structures of linear tetranuclear gold(I) chains can be modified by utilizing the stereoisomeric tetraphosphines, meso- and rac-dpmppm, which may lead to fine tuning of the strongly luminescent properties intrinsic to the Au(I) 4 cluster centers.

Inelastic neutron scattering, far-infrared spectroscopy, and cryogenic nuclear magnetic resonance are used to investigate the quantized rotation and ortho–para conversion of single water molecules trapped inside closed fullerene cages. The existence of metastable ortho -water molecules is demonstrated, and the interconversion of ortho -and para -water spin isomers is tracked in real time. Our investigation reveals that the ground state of encapsulated ortho water has a lifted degeneracy, associated with symmetry-breaking of the water environment.

The aim of this study was to evaluate the hypothesis that cerebral hemoglobin (Hb) oxygenation is related to phosphorylation potential during primary and secondary cerebral energy failure in newborn infants who have experienced birth asphyxia. We subjected newborn piglets to severe transient cerebral hypoxic-ischemia followed by resuscitation and examined cerebral energy metabolism by 31P-magnetic resonance spectroscopy and evaluated changes in cerebral Hb oxygen saturation (ScO2) using full-spectrum near-infrared spectroscopy before, during, and up to 54 h after the hypoxic-ischemic insult. ScO2 was significantly decreased during the hypoxic-ischemic insult compared with baseline values. During secondary energy failure, piglets were separated based on the relationship between the ratio of phosphocreatine to inorganic phosphate and ScO2; those with a negative correlation were less injured than those with a positive correlation. These results indicate that changes in ScO2 as measured by near-infrared spectroscopy are related to phosphorylation potential during secondary energy failure in asphyxiated infants.

Background: The light-emitting diode is used as one of the new light sources for phototherapy. NeoBLUE (Atom Medical, Tokyo, Japan) incorporates blue light-emitting diodes for the treatment of neonatal hyperbilirubinemia. The authors compared the in vitro efficacy of neoBLUE with conventional phototherapy devices. Methods: The three light devices used included neoBLUE and two conventional phototherapy devices with six blue–white (BW) or six green (GR) fluorescent tubes. A bilirubin/human serum albumin solution (15 mg/dL) in 200 × 300 mm elliptical bag was irradiated with each three light device. The average light intensity of neoBLUE, BW and GR was 22.5, 10.2 and 2.6 μW/cm2 per nm, respectively, for the irradiated area. Bilirubin photoisomers and native bilirubin were measured by high-performance liquid chromatography. Results: In neoBLUE, BW and GR, the respective production rate of cyclobilirubin was 6.0, 3.7 and 3.9 × 10−2 mg/dL/min, and the respective (4Z, 15E)-bilirubin/(4Z, 15Z)-bilirubin ratio after irradiation was 0.44, 0.33 and 0.12; the (4Z, 15Z)-bilirubin reduction rate at 20 min after irradiation was 60, 68 and 82%, respectively. The reduction rate of (4Z, 15Z)-bilirubin correlated with the (4Z, 15E)-bilirubin/(4Z, 15Z)-bilirubin ratio. Conclusion: Phototherapy using the neoBLUE under high level may be clinically more effective than therapy using the conventional light source from the results of the production rate of cyclobilirubin.

Background: The clinical effect of phototherapy for neonatal hyperbilirubinemia is based on the production and elimination of cyclobilirubin. Generally, the clinical effect of light sources is estimated by the reduction in the total serum bilirubin level. One procedure with less invasiveness than blood collecting is urine collection. Whether the effectiveness of light sources used for phototherapy could be assessed using measurements of bilirubin photoisomers in urine was studied. Methods: This study was a retrospective analysis of 38 term infants with hyperbilirubinemia who underwent phototherapy. Bilirubin fractions in serum and urine before and 24 h after the phototherapy were measured by high-performance liquid chromatography. The light sources used for the phototherapy were blue-white light (n = 11), Biliblanket plus high output (n = 13) or green light (n = 14). The relationships between serum and urine bilirubin photoisomers after phototherapy and whether the levels of urine bilirubin photoisomer are affected by the light sources with different wavelength characteristic were analyzed. Results: There was no correlation between serum (ZE)-bilirubin and urine configurational isomers, but a weak positive correlation between serum (EZ)-cyclobilirubin and urine structural isomers after phototherapy. Although serum (ZE)-bilirubin levels depended on the wavelength characteristic of each light source during phototherapy, the urine configurational isomer levels did not depend on it. The increase in serum (EZ)-cyclobilirubin levels and the urine structural isomer levels were mostly in agreement. Conclusions: The urine bilirubin structural isomers may be used to estimate the serum (EZ)-cyclobilirubin levels and to evaluate the clinical effects of light sources.

A study was conducted to determine the length of exposure to heat necessary to kill water-imbibing weed seeds at 55 and 60°C. The examination covered ten upland weed species: Solanum carolinense L., S. americanum Mill., Abutilon theophrasti Medic., Phytolacca americana L., Amaranthus spinosus L., A. patulus Bertoloni, Persicaria lapathifolia (L.) S. F. Gray, Panicum dichotomiflorum Michx, Echinochloa crus-galli (L.) Beauv. var. crus-galli and Digitaria ciliaris (Retz.) Koeler. All seeds of each species were killed by exposure to heat at 55°C for 72hr and at 60°C for 24hr except for those of Abutilon theophrasti (dormant seed rate 80%) which were killed by exposure for 120 and 30hr at the respective temeratures.These weed species fell into four groups, categorized by a combination of short-duration heat-tolerance (SDHT) and long-duration heat-tolerance (LDHT). SDHT was determined by the viability of weed seeds when treated at 60°C for 3hr, with low and high subcategories of tolerance. LDHT was detemined by the duration required to kill all the seeds at 1% level of significance when treated at 60°C, into three subcategories (low, medium and high tolerance). Persicaria lapathifolia, E. crus-galli, and D. ciliaris were low for both SDHT and LDHT (Group I), and Amaranthus spinosus and Panicum dichotomiflorum were low-SDHT and medium-LDHT (Group II). Solanum species, Phytolacca americana, and Amaranthus patulus were high-SDHT and medium-LDHT (Group III), while Abutilon theophrasti was low-SDHT and high-LDHT (Group IV). The viability of seeds at short-duration heat treatment for Group I, II and IV was low, but the durations required to kill all seeds were different among the groups. Group III consisted of species for which the viability of seeds at short-duration heat treatment was high, and the fatal duration was medium.For Abutilon teophrasti which required the longest duration of heat exposure to kill all seeds at each temperature, 95% confidence intervals of LD90 values were calculated using the probit method, and were 42 to 58 and 10 to 17hr at 55 and 60°C, respectively.

Adenine phosphoribosyltransferase deficiency is a disorder in which 2,8-dihydroxyadenine (2,8-DHA) crystalluria is caused by a congenital deficiency in the enzyme adenine phosphoribosyltransferase (APRT). In most cases, APRT deficiency is caused by autosomal recessive inheritance of a homozygote of the mutant gene APRT*Q0 or APRT*J, but there are also some cases in which the disorder is caused by the compound heterozygote APRT*Q0 and APRT*J. In the patients described here, brown round crystals were found in their urinary sediment. Crystalluria was the first sign of APRT deficiency, thereafter confirmed by genetic screening for APRT*/Q0 and APRT*. We performed genetic screening for APRT*Q0 and APRT*J in two families and diagnosed three cases of APRT*Q0 /APRT*J compound heterozygote-type APRT deficiency. Genetic screening for APRT*Q0 and APRT*J of family members is effective for early diagnosis and early treatment for family members.

Near-infrared spectroscopy has been used for measurement of changes in cerebral Hb concentrations in infants to study cerebral oxygenation and hemodynamics. In this study, measurements by time-resolved spectroscopy (TRS) were performed in 22 neonates to estimate the values of light absorption coefficient and reduced scattering coefficient (mu'(s)), cerebral Hb oxygen saturation (SCO2), cerebral blood volume (CBV), and differential pathlength factor (DPF), and the relationships between postconceptional age and mu'(s), SCO2, CBV, and DPF were investigated. A portable three-wavelength TRS system with a probe attached to the head of the neonate was used. The mean mu'(s) values at 761, 795, and 835 nm in neonates were estimated to be (mean +/- SD) 6.46 +/- 1.21, 5.90 +/- 1.15 and 6.40 +/- 1.16/cm, respectively. There was a significant positive relationship between postconceptional age and mu'(s) at those three wavelengths. The mean SCO2 value was calculated to be 70.0 +/- 4.6%, and postconceptional age and SCO2 showed a negative linear relationship. The mean value of CBV was 2.31 +/- 0.56 mL/100 g. There was a significant positive relationship between postconceptional age and CBV. The mean DPF values at 761, 795, and 835 nm were estimated to be 4.58 +/- 0.41, 4.64 +/- 0.46, and 4.31 +/- 0.42, respectively. There was no relationship between postconceptional age and DPF at those three wavelengths. The results demonstrated that our near-infrared TRS method can be used to monitor mu'(s), SCO2, CBV, and DPF in the neonatal brain at the bedside in an intensive care unit.

Background Phototherapy has been a standard treatment for neonatal hyperbilirubinemia for more than 40 years, but it has remained sub-optimal. Aims To clarify the developmental changes in parameters of (4 E , 15 Z )-cyclobilirubin (( EZ )-C) elimination in order to obtain basic data for establishing optimal phototherapy. Study design Blood samples were taken at regular intervals after stopping phototherapy, and bilirubin fractions were analyzed by high-performance liquid chromatography. Subjects and methods The subjects were 46 infants with hyperbilirubinemia who underwent phototherapy. The gestational age and birth weight of the subjects ranged from 25.0 to 41.0 weeks and from 656 to 3810 g, respectively, and the age at cessation of phototherapy was a median of 5 days. A kinetic model of ( EZ )-C elimination was established, and the serum half-life of ( EZ )-C was calculated on the basis of the determined model. Relationships of the half-life of ( EZ )-C with birth weight and gestational age were investigated. Results Serum ( EZ )-C elimination followed a first-order kinetic model in 43 infants and a zero-order kinetic model in three extremely low birth weight infants. The half-life of ( EZ )-C calculated on the basis of a first-order elimination model in serum ranged from 68 to 274 min and showed weak negative correlations with birth weight and gestational age. Conclusions Serum ( EZ )-C excretion followed a first-order kinetic model in most of the neonates. The half-life of ( EZ )-C becomes more prolonged in the very low birth weight infant and early gestational age.

Nine species of plants having antifeeding activities for the larvae of the yellow butterfly, Eurema hecabe mandarina DE L'ORZA, were found. From one of them, Arachniodes standishii (MOORE) OHWI, the known compound, 1-(2, 4, 6-trimethoxyphenyl) but-trans-2-en-1-one (I), was isolated as an antifeedant. This compound was synthesized according to the Friedel-Crafts procedure, which also gave two new compounds, 1, 3-bis (2, 4, 6-trimethoxyphenyl) butan-1-one (VI) and 1-(2, 4, 6-trimethoxyphenyl)-3-[3-(2-trans-butenoyl)-2, 4, 6-trimethoxyphenyl] butan-1-one (VII), as by-products. Treatment of 1, 3, 5-trimethoxybenzene (V) with ferric chloride was found to afford 2, 2', 4, 4', 6, 6'-hexamethoxybiphenyl (VIII), which has been synthesized according to Ullmann's procedure.