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Context There are limited reports on the detailed examination of steroid profiles for setting algorithms for 21-hydroxylase deficiency (21OHD) screening by liquid chromatography–tandem mass spectrometry (LC-MS/MS). Objective We aimed to define an algorithm for newborn screening of 21OHD by LC-MS/MS, measuring a total of 2077 dried blood spot samples in Tokyo. Methods Five steroids (17α-hydroxyprogesterone [17αOHP], 21-deoxycortisol [21DOF], 11-deoxycortisol [11DOF], androstenedione [4AD], and cortisol [F]) were included in the panel of LC-MS/MS. Samples from 2 cohorts were assayed: Cohort A, 63 “screening positive” neonates who were referred to an endocrinologist (n = 26 with 21OHD; n = 37 false-positive; obtained from 2015 to 2020); and Cohort B, samples (n = 2014) with 17αOHP values in the 97th percentile or above, in the first-tier test with 17αOHP ELISA from 2020 to 2021. Results Analysis of Cohort A revealed that the 3 indexes 21DOF, 11DOF/17αOHP, and (4AD + 17αOHP)/F had higher area under the curve (AUC) values (0.999, 0.997, 0.989, respectively), while the 17αOHP AUC was lower (0.970). Accordingly, in addition to 17αOHP, the 3 markers were included for defining the screening algorithm. The assay of Cohort B revealed that the new algorithm gave 92% of predicted positive predictive value without false-negative cases. We also determined the reference values for the 5 steroids at 4 to 7 days after birth, according to sex and gestational age (GA), revealing extremely low levels of 21DOF at any GA irrespective of sex differences. Conclusion Our study demonstrated the high relevance of 21DOF, (4AD + 17αOHP)/F, and 11DOF/17αOHP, rather than 17αOHP, for 21OHD screening.

This study aims to examine the reliability and validity of Home-visit Nursing Quality Indicators for Children (HNQIC) with medical complexity in Japan that will enable measuring the quality of services provided by home-visit nursing agencies (HNA) for children with medical complexity (CMC) and their families.This study employed a model that measures medical quality as proposed by Donabedian in a conceptual framework. The HNQIC is comprised of a total of 42 items with responses in 5-point Likert scale: 8 items in "Structure", 24 items in "Process", and 10 items in "Outcome". A self-rating questionnaire survey was administered and responses from 57 home-visit nursing agencies were analyzed. An exploratory factor analysis was performed to examine the validity of the construct, and a covariance structure analysis was performed to examine the structural validity of the model that measures medical quality.The "Structure" and "Process" sections included 28 items in 5 factors, and the "Outcome" section included 7 items in 3 factors. The Cronbach's α coefficient for all of the items of "Structure" and "Process" was 0.93, and that of "Outcome" was 0.76. As a result of a covariance structure analysis, we obtained following goodness-of-fit indices: χ2 / df = 1.41, GFI = .897, AGFI = .794, CFI = .926, and for the coefficient of determination .14 ≤ R2 ≤ .68.As the statistical validity of the HNQIC was confirmed, we determined the goodness-of-fit indices of the model to be acceptable.The findings suggested that the HNQIC can be used as a quality indicator to access care effects objectively to provide better support.

BACKGROUND One of the major purposes of newborn screening for 21-hydroxylase deficiency (21OHD) is preventing life-threatening adrenal crisis. However, the details of adrenal crisis in newborns are not precisely documented. AIM We aimed to clarify the clinical details of salt-wasting in newborn 21OHD patients. METHODS Based on the follow-up survey of the screening in Tokyo from 1989 to 2017, we retrospectively analysed the conditions of classical 21OHD neonates before the initiation of therapy. RESULTS One hundred classical 21OHD patients (55 male, 45 female) were analysed. The age at the first hospital visit was 0-20 days with sex difference (male: 9.0 ± 3.5 days; female: 6.2 ± 3.9 days). Thirty-seven (37.4%) patients exhibited severe salt-wasting (SSW), that is, Na 7 mEq/L or Na/K ratio 7 mEq/L and Na/K

The number of rubella cases has increased in Japan, especially among adults. Rubella infection in pregnant females can lead to congenital rubella syndrome (CRS). The Japanese government is promoting vaccination to prevent CRS. This study performs a cost-effectiveness analysis of the following four methods: (1) females who wished to become pregnant and partners, with an antibody-titer test, (2) females only, with an antibody-titer test, (3) females and males, without an antibody-titer test, (4) females only, without an antibody-titer test. A decision tree model with a hypothetical cohort of 500 males and 500 females was used for the analysis, and the parameters were obtained from previous studies. The number of avoidances of CRS was defined as the effect. Compared to the case where methods were not implemented, the number of CRS cases that can be prevented by implementing the methods was 0.0115589 by (1) and (3) and 0.0147891 by (2) and (4). The cost effectiveness of (1) to (4) was 287,413,677 JPY, 135,050,529 JPY, 388,524,974 JPY, and 197,744,219 JPY, respectively (1 JPY = 0.00963247 USD). Method (2) was the most cost-effective and did not change by sensitivity analysis. We conclude that the vaccination for females only with an antibody-titer test is recommended.

Context We previously reported that inorganic iodine therapy in lactating women with Graves disease (GD) did not affect the thyroid function in 25 of 26 infants despite their exposure to excess iodine via breast milk. Objective To further assess thyroid function in infants nursed by mothers with GD treated with inorganic iodine. Design Case series Setting Tajiri Thyroid Clinic, Japan Participants One hundred infants of lactating mothers with GD treated with potassium iodide (KI) for thyrotoxicosis Main Outcome Measures Infant blood thyrotropin (TSH) and free thyroxine (FT4) levels were measured by the filter paper method. Subclinical hypothyroidism was defined as TSH ≥10 μIU/mL and ≥5 μIU/mL in infants aged Results Overall, 210 blood samples were obtained from 100 infants. The median infant age was 5 (range, 0-23) months; median maternal KI dose, 50 (4-100) mg/day; median blood TSH level, 2.7 (0.1-12.3) μIU/mL; and median blood FT4 level, 1.04 (0.58-1.94) ng/dL. Blood TSH level was normal in 88/100 infants. Twelve infants had subclinical hypothyroidism; among them, blood TSH levels normalized after maternal KI withdrawal or stopping breastfeeding in 3 infants. In 7 infants, blood TSH levels normalized during KI administration without stopping breastfeeding. Two infants could not be followed up. Conclusion In Japan, inorganic iodine therapy for lactating women with GD did not affect thyroid function in most of the infants. Approximately 10% of infants had mild subclinical hypothyroidism, but blood TSH level normalized during continued or after discontinuing iodine exposure in all followed up infants.

Context: The effects of maternal inorganic iodine therapy on infant thyroid function are not well known. Objective: This study investigated the effects on infant thyroid function of maternal inorganic iodine therapy when administered to lactating mothers with Graves disease. Design and Setting: This study was a prospective case series performed at the Tajiri Thyroid Clinic, Kumamoto, Japan. Participants: Subjects were 26 infants of lactating mothers with Graves disease treated with potassium iodide (KI) for postpartum thyrotoxicosis. Main Outcome Measures: Infant blood levels of thyroid-stimulating hormone (TSH) and free thyroxine were measured using the dried filter-paper method. Iodine concentrations in breast milk and infant urine were measured on the same day. Subclinical hypothyroidism was defined as a blood TSH level of ≥10 or ≥5 μIU/mL in, Thyroid function was assessed in infants of lactating mothers with Graves disease who were treated with inorganic iodine. Despite iodine overload, thyroid function was not affected in most infants.

The Nankai Trough in Japan has been identified as a geological feature that could cause extensive damage in the event of a major earthquake. In this study, we investigated the impact of effective guidance signs for hearing-impaired individuals requiring special care when escaping to a tsunami evacuation building (emergency evacuation location) using geographical information system (GIS) and viewshed analysis. We selected an area we considered would suffer severe damage following a major earthquake and tsunami; we identified difficulties in the provision of escape routes. Using GIS, we determined the time required for escape and tsunami arrival time if effective signs were installed; we undertook such analysis using the height data of buildings in the target area. With effectively installed guidance signs, the average required evacuation time was 36.88 minutes; without such signs (which is currently the case in the target area), the average time was 47.10 minutes: that would result in citizens getting caught by the tsunami. Installing effective guidance signs would allow hearing-impaired individuals to escape to an evacuation building before being hit by the tsunami.

Background Congenital adrenal hyperplasia (CAH) cause life-threatening adrenal crisis. It also affects fetal sex development and can result in incorrect sex assignment at birth. In 1989, a newborn screening program for congenital adrenal hyperplasia (CAH) was introduced in Tokyo. Here we present the results of this screening program in order to clarify the efficiency of CAH screening and the incidence of CAH in Japan. Method From 1989 to 2013, a total of 2,105,108 infants were screened for CAH. The cutoff level for diagnosis of CAH was adjusted for gestational age and birth weight. Results A total of 410 infants were judged positive, and of these, 106 patients were diagnosed with CAH, indicating a positive predictive value (PPV) of 25.8 %. Of the 106 patients, 94 (88.7 %) were diagnosed with 21-OHD. Of these 94 patients, 73 were diagnosed with the salt wasting form, 14 with the simple virilising form and 7 with the nonclassical form (NC21OHD). The mean birth weight and gestational age were 3192 ± 385 g and 38.9 ± 1.38 weeks. 11 out of 44 female patients were assigned as female according to their screening result. Conclusions These data suggest that the newborn screening in Tokyo was effective, especially for sex assignment and preventing fatal adrenal crisis. The incidence of CAH was similar to that measured in previous Japanese screening studies, and it was also similar to that of western countries. The incidence of NC21OHD in Japan in the present study was lower than that in western countries as previous studies reported. The screening program achieved higher PPV than previous CAH screening studies, which might be due to the use of variable cutoffs according to gestational age and birth weight. However, most of the neonates born at 37 weeks or less that were referred to hospital were false-positives. Further changes are needed to reduce the number of false positive preterm neonates.

We have developed a novel mobile bioprobe using a conjugate of a kinesin-driven microtubule (MT) and malachite green (MG) as a platform for capturing MG RNA aptamers. The fluorescence of MG increases when it is bound to an MG aptamer, allowing MT-MG conjugates to work as sensors of RNA transcripts containing the MG aptamer sequence. Kinesin motor proteins provide an effective driving force to create mobile bioprobes without any manipulation. Although the fluorescence of a small number of MG-binding aptamers is low, the self-organization of tubulins into MTs enables the microscopic observation of the bound aptamers by collecting them on MTs. We demonstrate that MT-MG conjugates can select target aptamers from a transcription mixture and transport them without losing their inherent motility. Because the MG aptamer binds MG in a reversible manner, MT-MG conjugates can conditionally load and unload the target aptamers. This is one advantage of this system over the molecular probes developed previously in which reversible unloading is impossible due to high-affinity binding, such as between avidin and biotin. Furthermore, an MT-MG conjugate can be used as a platform for other MG aptameric sensors with recognition regions for various target analytes optimized by further selection procedures. This is the first step to applying living systems to in vitro devices. This technique could provide a new paradigm of mobile bioprobes establishing high-throughput in vitro selection systems using microfluidic devices operating in parallel.

To examine the functional role of the essential light chain (ELC) in the phosphorylation-dependent regulation of smooth muscle myosin, we replace the native light chain in smooth muscle myosin with bacterially expressed chimeric ELCs in which one or two of the four helix-loop-helix domains of chicken gizzard ELC were substituted by the corresponding domains of scallop (Aquipecten irradians) ELC. All of these myosins, regardless of the ELC mutations or regulatory light chain (RLC) phosphorylation, showed normal subunit constitutions and NH(4)(+)/EDTA-ATPase activities, both of which were similar to those of native myosin. None of the ELC mutations changed the actin-activated ATPase activity of myosin in the absence of RLC phosphorylation. However, in the presence of RLC phosphorylation, the substitution of domain 1 or 2 in the ELC significantly decreased the actin-activated ATPase activity, whereas the substitution of both of these domains did not change the activity. In contrast to myosin, the domain 2 substitution in the ELC did not affect the actin-activated ATPase activity of single-headed myosin subfragment 1. These results suggest an interhead interaction between domains 1 and 2 of ELCs which is required to attain the full actin-activated ATPase activity of smooth muscle myosin in the presence of RLC phosphorylation.

Previous studies indicated that single-headed smooth muscle myosin and S1 (a single head fragment) are not regulated through phosphorylation of the regulatory light chain (RLC). To investigate the importance of the double-headedness of myosin and of the S2 region for the phosphorylation-dependent regulation, we made three types of recombinant mutant smooth muscle HMMs with one intact head and an N-terminally truncated head. The truncated head of Delta MD lacked the motor domain, that of Delta(MD+ELC) lacked the motor and essential light chain binding domains, and single-headed HMM had one intact head alone. The basal ATPase activities of the three mutants decreased as the KCl concentration became less than 0.1 M. Such a decrease was not observed for S1, which had no S2 region, suggesting that S2 is necessary for this myosin behavior. This activity decrease also disappeared when RLCs of Delta MD and Delta(MD+ELC), but that of single-headed HMM, were phosphorylated. When their RLCs were unphosphorylated, the three mutants exhibited similar actin-activated ATPase levels. However, when they were phosphorylated, the actin-activated ATPase activities of Delta MD and Delta(MD+ELC) increased to the S1 level, while that of single-headed HMM remained unchanged. Even in the phosphorylated state, the actin-activated ATPase activities of the three mutants and S1 were much lower than that of wild-type HMM. We propose that S2 has an inhibitory function that is canceled by an interaction between two phosphorylated RLCs. We also propose that a cooperative interaction between two motor domains is required for a higher level of actin activation.

Single-headed myosin was prepared by digestion of porcine aorta smooth muscle myosin with Staphylococcus aureus V8 protease in the presence of actin. The single-headed myosin preparation contained intact light chains, a rod fragment of a heavy chain, and a heavy chain of which only a minor fraction contained a nick in the head segment. Below 0.2 M NaCl, the single-headed myosin showed a decrease in Ca2+-ATPase activity and an increase in the elution time on gel filtration HPLC in a phosphorylation-dependent manner, indicating a phosphorylation-dependent conformational transition between the extended and folded forms. These conformations were confirmed by electron microscopic observation of rotary-shadowed samples of single-headed myosin. However, the conformational transition of single-headed myosin occurred in a narrower range with lower salt concentrations than that of double-headed myosin. The filament assembly of single-headed myosin was thus facilitated and phosphorylation-independent. The single-headed myosin also showed high actin-activated ATPase activity independent of phosphorylation. These results indicate that the two-headed structure of smooth muscle myosin is not essential for the conformational transition, but is required for the phosphorylation-dependent regulation of enzymatic activity and filament assembly.

The exchange of 17-kDa essential light chain (LC17) in smooth muscle myosin was carried out by incubating myosin with a 10-fold molar excess of exogenously added LC17 over the corresponding endogenous light chain in the presence of trifluoperazine and 4.5 m ammonium chloride. Porcine aorta myosin contains two kinds of LC17 isoform, LC17nm and LC17gi, while chicken gizzard myosin contains only one kind of LC17 isoform. As LC17gi can be separated from LC17nm and gizzard LC17 by urea–gel electrophoresis, LC17nm in aorta myosin and LC17 in gizzard myosin were exchanged with LC17gi and LC17gi in aorta myosin was exchanged with LC17nm, and the degree of exchange was estimated by urea–gel electrophoresis. Under the optimal conditions (6 and 10°C for aorta and gizzard myosin, respectively), nearly 90% of exchange, which is close to the theoretical value, was achieved for the former combinations, and a slightly lower exchange was obtained for the latter. The LC17-exchanged myosins contained stoichiometric amounts of the heavy and light chains and retained the original nature in the phosphorylation-dependent actin-activated ATPase activity, 6S–10S conformational transition, and filament assembly.

Selective photocrosslinking reaction between 3-cyanovinylcarbazole nucleoside (CNVK) and 5-methylcytosine (mC), which is known as epigenetic modification in genomic DNA, was developed. The reaction was completely finished within 5 s of 366 nm irradiation, and the rate of this photocrosslinking reaction was ca. 30-fold higher than that in the case of unmodified normal cytosine. There were no significant differences in the thermodynamic parameters and the kinetics of hybrid formation of oligonucleotide (ODN) containing CNVK and its complementary ODN containing C or mC at the photocrosslinking site, and suggesting that the quick and selective photoreaction has potential for the selective detection of mC in the DNA strand via the photocrosslinking reaction.

Local cerebral blood flow was measured in 10 high-risk infants with neonatal episodic neurological events at 41–44 post-conceptional weeks using N-isopropyl-p-[ 123 I]iodoamphetamine (IMP) and single photon emission computed tomography (SPECT). In 5 of the 7 infants with normal neurological outcome, prominent cerebral perfusion was found in the basal ganglia, brainstem, cerebellum, parietal white matter, and sensory motor cortex. The frontal lobes showed poor relative perfusion. In 3 infants with severe neurological deficits, SPECT demonstrated severe hypoperfusion of all parts of the brain except the basal ganglia, brainstem and sensorimotor cortex. However, MRI revealed non-specific changes, such as poor myelination and ventricular dilatation. SPECT, when performed in the first weeks of life, can be useful and may be more sensitive than MRI in predicting the occurrence of major neurological handicaps. However, because of the relatively invasive character and high cost of SPECT, SPECT should not necessarily be performed in all high-risk neonates.

The development of posture in the prone and supine positions was studied longitudinally in 10 low risk preterm infants between 31 and 39 weeks' postmenstrual age whose subsequent neurological development at 18 months old was normal. The infants were observed from one week after birth until the expected date of delivery. All postures were analysed according to the procedures described by Prechtl et al. There were large intraindividual and interindividual differences in posture in terms of the duration and incidence of the two positions. There was no age specific preferred posture found in either position. The posture duration in the prone position was longer than that in the supine position, but overall flexed and abducted posture were observed more often in the former. Turning of the head to the right side was also observed more often in the prone than in the supine position.

Normal development and maturation in pre- and postnatal periods were studied using MR imaging. For this purpose, we performed MR imaging at a postmenstrual age of 37-44 weeks in both low-risk preterm and fullterm infants and assessed the myelination pattern and the dimension of the pituitary gland, corpus callosum, pons and cerebellar vermis. There were no differences in stages of myelination and the size of these structures in both groups. MR imaging was also performed in infants with various cerebral injuries. Focal or diffuse areas of hyperintensity on T2-weighted images and delayed myelination were the commonly observed abnormal findings in these infants.

We studied the frequency and clinical value of cerebrospinal fluid flow void in 49 normal children who underwent MRI on a 0.35 T unit. T2-weighted axial SE images were retrospectively analysed to determine relative signal intensities of the fourth, third and lateral ventricles and the cerebral aqueduct, rated as high intensity, low intensity, and no signal (flow void). Flow void was seen in the fourth ventricle in 20% of children up to 3 months of age, 67% from 4 to 6 months of age, in all children aged between 7 months and 2 years and in about half of those aged more than 3 years. In cerebral aqueduct the figures were 40% up to 1 month, age, 80% at 2-3 months and 100% above 4-6 months of age, and in the third ventricle 0% up to 1 month, 60% at 2-3 months, 67% at 4-6 months, and almost 100% in above 7 months. Flow void was much more frequent at 1-6 years of age than in adults and less frequent in neonates, which may reflect the different compliance of the growing brain.

Photo-induced artificial RNA editing was demonstrated using photo-reactive oligonucleotides containing 3-cyanovinylcarbazole nucleoside. This non-enzymatic and sequence-specific methodology will make a major contribution to the elucidation of RNA functions including non-coding RNAs and to the development of drugs based on sequence-specific RNA editing.

Normal brain maturation was evaluated with MR imaging of 36 neonate to 2-year-old patients. The myelination process in centrum semiovale was quantitatively assessed in 50 6-months- to 15-year-old children, and 40 adults aged 16-60 years. Imaging was performed with a 0.35 T superconducting MR unit using spin echo pulse sequences. On T1-weighted images, three stages of maturation could be observed: (1) neonates within 1 month; (2) 1-6 months of age; and (3) adult configuration after 6-7 months of age. Also on T2-weighted images three maturation stages could be defined: (1) neonatal pattern in the first 6 months of life; (2) signal inversion between 6-18 months; and (3) adult appearance after 18 months. Thus, the combination of T1- and T2-weighted images could lead us to the assessment of brain maturation in infants younger than 2 years. The myelination process in centrum semiovale was fast during the first 3 years followed by slow progression until 20-30 years of age.

Magnetic resonance imaging was performed in 9 preterm infants at 37–43 weeks postmenstrual age. They all were born at 26–35 weeks gestation. Myelination was graded according to its most cephalic location. Myelination pattern 2 (myelination observed in the posterior limb of the internal capsule and adjacent structures of the thalamus and lenticular nucleus) was demonstrated in 2 infants, pattern 3 (myelination of the corona radiata) in 3 infants, and pattern 4 (myelination of the centrum semiovale) in 4 infants. Bilateral low intensity areas were found on T 1 -weighted images in 7 infants and a ribbon-like, high intensity was observed in 5. These findings revealed a wide variety of magnetic resonance imaging appearance in apparently normal preterm infants. Caution is needed in interpreting the pathologic nature of such features in preterm infants during the perinatal period.

Twenty-one infants younger than 12 months of age were diagnosed as having periventricular hyperintensity (PVH) on T2-weighted magnetic resonance imaging. Ten infants had experienced neonatal asphyxia, 6 intracranial hemorrhage, 2 bacterial meningitis, and 3 apnea. PVH was classified according to its extent. Round foci of PVH surrounding the frontal and occipital horns of the lateral ventricles were observed in 4 infants (PVH pattern I). Continuous PVH was observed in 17 infants (PVH patterns II and III). Fourteen infants with continuous PVH had spastic diplegia or quadriplegia. Developmental delay was demonstrated in 15 infants with continuous PVH. No PVH pattern I infants had cerebral palsy; only 1 such infant had mild developmental delay. Our study suggests that the extent of PVH reflects the severity of brain damage in neonates with cerebral injuries.

DNA-loaded microtubules (MTs) moving on a kinesin motor protein-coated substrate can selectively hybridize with a target fully matched DNA over single-base mismatched DNA and transport it. This technique is capable of collecting target biomolecules toward one point site to design new methodology of DNA analysis.

We measured saccadic response time (SRT) to investigate developmental changes related to spatially aligned or misaligned auditory and visual stimuli responses. We exposed 4-, 5-, and 11-month-old infants to ipsilateral or contralateral auditory-visual stimuli and monitored their eye movements using an electro-oculographic (EOG) system. The SRT analyses revealed four main results. First, saccades were triggered by visual stimuli but not always triggered by auditory stimuli. Second, SRTs became shorter as the children grew older. Third, SRTs for the ipsilateral and visual-only conditions were the same in all infants. Fourth, SRTs for the contralateral condition were longer than for the ipsilateral and visual-only conditions in 11-month-old infants but were the same for all three conditions in 4- and 5-month-old infants. These findings suggest that infants acquire the function of auditory-visual spatial integration underlying saccadic eye movement between the ages of 5 and 11 months. The dependency of SRTs on the spatial configuration of auditory and visual stimuli can be explained by cortical control of the superior colliculus. Our finding of no differences in SRTs between the ipsilateral and visual-only conditions suggests that there are multiple pathways for controlling the superior colliculus and that these pathways have different developmental time courses.

Kinesin is a linear motor protein driven by energy released by ATP hydrolysis. In the present work, we genetically installed an M13 peptide sequence into Loop 12 of kinesin, which is one of the major microtubule binding regions of the protein. Because the M13 sequence has high affinity for Ca(2+)-calmodulin, the association of the engineered kinesin with microtubules showed a steep Ca(2+)-dependency in ATPase activity at Ca(2+) concentrations of pCa 6.5-8. The calmodulin-binding domain of plant kinesin-like calmodulin-binding protein is also known to confer Ca(2+)-calmodulin regulation to kinesins. Unlike this plant kinesin, however, our novel engineered kinesin achieves this regulation while maintaining the interaction between kinesin and microtubules. The engineered kinesin is switched on/off reversibly by an external signal (i.e., Ca(2+)-calmodulin) and, thus, can be used as a model system for a bio/nano-actuator.

This investigation ascertains whether, in (smooth muscle) myosin, certain residues engage in functional interactions with their actin conjugates in an actomyosin complex. Such interactions have been postulated from putting together crystallographic models of the two proteins [Rayment, I., Rypniewski, W. R., Schmidt-Bäse, K., Smith, R., Tomchick, D. R., Benning, M. M., Winkelmann, D. A., Wesenberg, G., and Holden, H. M. (1993) Science 261, 50-58]. Here, in several instances, we ask whether mutation of a particular residue significantly impairs a function, and find that the answers are largely rationalized by the original postulation. Additionally, a novel element emerges from our investigation. To assess function, we test the wild type and mutant systems as they perform in the steady state of ATP degradation. In doing so, we assume, as usual, that degradation proceeds from an early stage in which the complex forms (and is described by parameter K(app)) to a later stage during which the product leaves the complex (and is described by parameter V(max)). Interestingly, certain defects induced by the mutations are associated with changes in K(app), and other defects are associated with changes in V(max), suggesting that our procedure at least roughly distinguishes between events according to the time in the degradation at which they occur. In this framework, we suggest that (1) in the actin-myosin association phase, cationic residues Lys-576 and Lys-578 interact with anionic residues of the so-called second actin, and (2) in the product leaving phase, hydrophobic residues Trp-546, Phe-547, and Pro-548, as well as the Thr-532/Asn-533/Pro-534/Pro-535 sequence, sever connections with the so-called first actin. The role of Glu-473 is also examined.

Initially, we asked which (of 10) smooth muscle myosin head residues responds to MgADP or MgATP binding with enhanced fluorescence emission (Trp-441 and Trp-512 were leading candidates)? To decide, we prepared sham-mutated smooth muscle heavy meromyosin (HMM), W441F HMM, and W512F HMM. On adding MgATP, emission of wild-type and W441F HMMs increased by 25–27%, but that of W512F HMM by 5%. So, in myosin, 512 is the “sensitive Trp.” Unexpectedly, properties of W512F HMM [elevated Ca 2+ -ATPase, depressed EDTA (K + )-ATPase, no regulation of its basal or actin-activated Mg 2+ -ATPase by phosphorylation of its “regulatory” light chain, limited actin activation, and inability to move actin filaments in a motility assay] are strikingly like those of smooth muscle myosin reacted at Cys-717 with thiol reagent. From crystallography-based [Houdusse, A., Kalabakis, V. N., Himmel, D., Szent-Györgyi, A. G. & Cohen, C. (1999) Cell 97, 459–470] simulations, we found that in wild-type HMM with MgADP added, Trp-512 is in a “hydrophobic pocket,” but that pocket becomes distorted in W512F HMM. We think that there is a “path of influence” from 512 to 717 to the active site. We suggest that the mutational changes at 512 are transmitted along this path to Cys-717, where they induce changes similar to those caused by reacting wild-type HMM with thiol reagent.

Rabbit skeletal myosin forms stable filaments under physiological conditions, and only a small amount stays as a monomer in equilibrium with filaments. The myosin monomers were observed in two conformational states, as extended and folded forms upon electron microscopy and gel filtration high performance liquid chromatography. The fraction of monomers in the folded conformation increased with a decrease in the concentration of NaCl below 0.2 M, and the conformational state was affected neither by the presence of ATP nor by the phosphorylation of regulatory light chain. In most of the folded monomers, the tail bent back toward the heads at one region, 45 nm apart from the head-tail junction, and the remaining tail portion containing the C-terminal tip appeared to interact with the head-tail junction. Only a small percentage of the folded monomers was in a more compact conformation close to the 10 S conformation of vertebrate smooth muscle and non-muscle myosins. The folded monomers, however, may not trap the products of ATP hydrolysis as assessed by single turnover experiments. The percentage of monomers in the 10 S-like conformation was increased by the exchange of a regulatory light chain with the smooth muscle light chain, indicating the participation of head-tail junction, including the regulatory light chain in the formation of folded conformation. The folded conformation may be common to various myosin IIs, suggestive of common roles for the folded monomers.

The laterality of head position, spontaneous finger movements, hand-face contact, and hand-mouth contact was studied in low-risk preterm infants of 31 to < 37 weeks postconceptional age (intrauterine + neonatal period at time of study). The head was predominantly turned towards the right side during the preterm period. Hand-mouth contact was more frequent on the right side and coincided well with the side to which the head was turned. Other hand movements, too, were more frequent on the right side than on the left, but these were also seen in the fingers contralateral to the direction in which the head was turned. These findings suggest that even before birth a spontaneous preference for head position is present and is already associated with asymmetry in coordinated finger movements.

Magnetic resonance imaging (MRI) was performed on five patients with infantile spasms who were treated with relatively low doses of adrenocorticotrophic hormone (ACTH) to study the extent of brain shrinkage induced by ACTH therapy. MRI prior to ACTH therapy revealed periventricular hyperintensity (PVH) areas and poor myelination in four patients. In one case, MRI performed 2 days after initiation of ACTH therapy also showed PVH and poor myelination. Brain shrinkage was observed 2 weeks after initiation of ACTH therapy. The most impressive follow-up finding upon MRI was the decrease in PVH found in four patients. The differentiation between myelinated white matter and surrounding cortex became poorer in three cases. Cortical atrophy progressed in all patients but ventricular dilation progressed in only one patient. At the end of ACTH therapy, ventricular dilation progressed in all cases. These findings suggest that loss of water not only from periventricular white matter but also from cortex is the main etiological factor of brain shrinkage induced by ACTH.

A Japanese boy aged 13 months was referred to us because thickened ribs had been observed on a chest X-ray taken during a respiratory infection. mucopolysaccharidosis type VI (MPS VI) was diagnosed based on urinary glycosaminoglycan analysis and low activity of arylsulfatase B in peripheral leukocytes. He had mild pupillary membrane remnants, but no corneal opacities. The auditory brainstem response revealed moderate hearing impairment, which may have caused his subnormal DQ score of 85 at the age of 19 months. Although MPS VI is characterized by normal intellectual development with normal hearing in early infancy, it is important to examine for hearing loss, especially when an infant with this disease shows developmental delay.

SUMMARY The growth pattern of the pituitary gland of 86 infants, children and adolescents without pituitary or hypothalamic dysfunction was studied with sagittal magnetic resonance imaging. Postnatally the gland grew rapidly, reaching a plateau at almost three years after birth, and growing rapidly again between the age of 10 to 13 years. Pituitary gland area showed a similar growth pattern to gland height. The pituitary glands of seven patients with pituitary adenomata were also examined. All had convex upper-gland margins, with height and area significantly greater than those of normal controls of the same age. RESUME Allure de la croissance de l'hypophyse normale et dans l'adenome hypophysaire L'allure de la croissance de l'hypophyse a ete etudiee par imagerie de resonance magnetique sagittale chez 86 nourrissons, enfants et adolescents sans trouble de la fonction hypophysaire ou hypothalamique. Apres la naissance, la glande grossit rapidement, atteignant un plateau a presque trois ans apres la naissance, et a nouveau rapidement entre 10 et 13 ans. La surface hypophysaire presentait une allure de croissance comparable a la hauteur de la glande. Les hypophyses de sept patients porteurs d'adenome hypophysaire furent aussi examinees. Toutes presentaient une marge superieure convexe, avec une hauteur et une surface significativement plus grandes que celles des controles normaux de meme âge. ZUSAMMENFASSUNG Wachstumsmuster der normalen Hypophyse und beim Hypophysenadenom Bei 86 Sauglingen, Kindern und Jugundlichen ohne Hypophysenoder Hypothalamusdysfunktion wurde mit der sagittalen Kernspinntomographie das Wachstumsmuster der Hypophyse untersucht. Nach der Gebert wuchs die Druse sehr schnell, erreichte mit fast drei Jahren nach der Geburt ein Plateau und wuchs dann nochmal rapide zwischen 10 und 13 Jahren. Die Flache der Hypophyse zeigte ein ahnliches Wachstumsmuster wie die Hohne der Druse. Auzerdem wurden die Hypophysen von sieben Patienten mit Hypophysenadenomen untersucht. Alle hatten einen konvexen oberen Rand und eine signifikant grozere Hohe und Flache als die der normalen Kontrollen desselben Alters. RESUMEN Esquemas de crecimiento de la pituitaria normal y del adenoma de hipofisis Los patrones de crecimiento de la glandula pituitaria de 86 lactantes, ninos y adolescentes, sin disfuntion pituitaria o hipotalamica fueron estudiados por medio de la Resonancia Magnetica sagital. Despues del nacimiento, la glandula crecio rapidamente alcanzando una meseta a casi tres anos despues de nacimiento, creciendo despues de nuevo entre los 10 y 13 anos. El area de la glandula pituitaria mostro un patron de crecimiento similar al patron de la altura de la glandula. Se examinaron tambien las glandulas pituitarias de siete pacientes con adenoma pituitario. Todos tenian unos margenes superiores convexos, con el area y la altura significativamente mas grandes que los de los controles normales de la misma edad.

A three year-eight month old Japanese girl with Niemann-Pick disease type B was reported. She was short in stature. There was a hepatosplenomegaly and an abnormality on the chest X-ray. Bone marrow aspiration smear showed typical Niemann-Pick cells.

The development and aging of four brain midline structures--the pituitary gland, pons, cerebellar vermis, and corpus callosum--were studied. The dimensions and area of these structures were measured by means of midsagittal magnetic resonance imaging. The study group consisted of 94 patients newborn to 15 years old and 49 patients and seven volunteers 16-60 years old. Except for growth spurts in the 1st year and in the 10-15-year age range, the pituitary gland showed linear growth. The pons, cerebellar vermis, and corpus callosum all showed exponential growth. The cerebellar vermis showed the sharpest 1st-year growth spurt, followed by the corpus callosum and the pons. The pituitary gland showed a decrease in size in the 51-60-year age range. The corpus callosum also showed a tendency to diminish in size but to a lesser degree. There were no statistically significant declines in the size of either the pons or the cerebellar vermis in the 51-60-year age range.

A 21-month-old boy with septo-optic dysplasia and infantile spasms is reported. Eighteen hours after birth he had generalized convulsions, dyspnea, and hypoglycemia which were followed by recurrent clonic seizures despite administration of phenobarbital and valproic acid. At 16 months of age he had hypoglycemia and apnea attacks during varicella infection. At 19 months of age left hemiconvulsions and left hemiparesis occurred; his mental and motor development, which had been delayed but progressive, deteriorated. Tonic spasms appeared at 21 months of age and electroencephalography revealed multifocal spikes. At 27 months of age electroencephalography disclosed hypsarrhythmia. Cranial computed tomography depicted brain atrophy, right microphthalmia, and intact septum pellucidum. Magnetic resonance imaging demonstrated hypoplasia of the corpus callosum and a small pituitary gland. Coloboma of the right optic disc was detected. Physical examination revealed short stature, left hemiparesis, micropenis, and cryptorchidism. Endocrinologic loading tests revealed hypofunction of the hypophysial anterior lobe.

Three neonatal patients with superior sagittal sinus thrombosis are reported. The neurologic signs were bulging of the anterior fontanel and clonic hemi-convulsions. Neonatal polycythemia was believed to be an etiologic factor in two patients. Computed tomography revealed massive edema with slit-like ventricles in two patients. Increased density of the torcular Herophili and straight sinus also were demonstrated in two patients. The diagnosis of superior sagittal sinus thrombosis was confirmed by cerebral angiography in one patient and by digital subtraction angiography in the other two patients. Digital subtraction angiography appears to offer a definite advantage in the diagnosis of cerebral sinus thrombosis in the neonatal period.

Magnetic resonance imaging was performed in 8 patients with muscle disease and 6 normal controls. High intensity areas of varying dimensions were found in thigh muscles of the patients with progressive muscular dystrophy (PMD) and congenital myopathy. Shortened T, and prolonged T2 values with disease progression were characteristic. The T, values were variable and prolonged, T2 values were more characteristic of progressive muscular degeneration. The T, value may help to detect the early stage of PMD. Magnetic resonance imaging is useful in detecting the muscle lesions in PMD and essential for selection of a biopsy site.