Coordinate Normalization of Live-Cell Imaging Data Reveals Growth Dynamics of the Arabidopsis Zygote

Polarization of the zygote defines the body axis during plant development. In Arabidopsis (Arabidopsis thaliana), the zygote becomes polarized and elongates in the longitudinal direction, ultimately forming the apical-basal axis of the mature plant. Despite its importance, the mechanism for this elongation remains poorly understood. Based on live-cell imaging of the zygote, we developed new image analysis methods, referred to as coordinate normalization, that appropriately fix and align positions in an image, preventing fluctuation across a temporal sequence of images. Using these methods, we discovered that the zygote elongates only at its apical tip region, similar to tip-growing cells such as pollen tubes and root hairs. We also investigated the spatiotemporal dynamics of the apical tip contour of the zygote and observed that the zygote tip retains its isotropic, hemispherical apical shape during cell elongation. By looking at the elliptical fitting of the contour over time, we further discovered that the apical cell tip becomes thinner at first and then thickens, with a transient increase in growth speed that is followed by the first cell division. We performed the same series of analyses using root hairs and established that both the hemispherical tip shape and the changes in growth rate associated with changes in tip size are specific to the zygote. In summary, the Arabidopsis zygote undergoes directional elongation as a tip-growing cell, but its tip retains an unusual isotropic shape, and the manner of growth changes with the developmental stage.

Shoot gravitropism and organ straightening cooperate to arrive at a mechanically favorable shape in Arabidopsis

Gravitropism is the plant organ bending in response to gravity, while a straightening mechanism prevents bending beyond the gravitropic set-point angle. The promotion and prevention of bending occur simultaneously around the inflorescence stem tip. How these two opposing forces work together and what part of the stem they affect are unknown. To understand the mechanical forces involved, we rotated wild type and organ-straightening-deficient mutant (myosin xif xik) Arabidopsis plants to a horizontal position to initiate bending. The mutant stems started to bend before the wild-type stems, which led us to hypothesize that the force preventing bending was weaker in mutant. We modeled the wild-type and mutant stems as elastic rods, and evaluated two parameters: an organ-angle-dependent gravitropic-responsive parameter (β) and an organ-curvature-dependent proprioceptive-responsive parameter (γ). Our model showed that these two parameters were lower in mutant than in wild type, implying that, unexpectedly, both promotion and prevention of bending are weak in mutant. Subsequently, finite element method simulations revealed that the compressive stress in the middle of the stem was significantly lower in wild type than in mutant. The results of this study show that myosin-XIk-and-XIf-dependent organ straightening adjusts the stress distribution to achieve a mechanically favorable shape.

Thickness-stiffness trade-off improves lodging resistance in rice

Lodging of cereal crops significantly reduces grain yield and quality, making lodging resistance a prime target for breeding programs. However, lodging resistance among different rice (Oryza sativa L.) cultivars in the field remains largely unknown, as is the relationship between the major properties of culms such as their morphological and mechanical properties. Here, we investigated the morphological and mechanical properties of 12 rice cultivars by considering different internodes within culms. We detected variation in these two traits among cultivars: one set of cultivars had thicker but softer culms (thickness-type), while the other set of cultivars showed stiffer but thinner culms (stiffness-type). We designate this variation as a thickness-stiffness trade-off. We then constructed a mechanical model to dissect the mechanical and/or morphological constraints of rice culms subjected to their own weight (self-weight load). Through modeling, we discovered that ear weight and the morphology of the highest internode were important for reducing deflection, which may be important factors to achieve higher lodging resistance. The mechanical theory devised in this study could be used to predict the deflection of rice culms and may open new avenues for novel mechanics-based breeding techniques.

Pulvinar slits: Cellulose-deficient and de-methyl-esterified pectin-rich structures in a legume motor cell

The cortical motor cells (CMCs) in a legume pulvinus execute the reversible deformation in leaf movement that is driven by changes in turgor pressure. In contrast to the underlying osmotic regulation property, the cell wall structure of CMCs that contributes to the movement has yet to be characterized in detail. Here, we report that the cell wall of CMCs has circumferential slits with low levels of cellulose deposition, which are widely conserved among legume species. This structure is unique and distinct from that of any other primary cell walls reported so far; thus, we named them "pulvinar slits." Notably, we predominantly detected de-methyl-esterified homogalacturonan inside pulvinar slits, with a low deposition of highly methyl-esterified homogalacturonan, as with cellulose. In addition, Fourier transform infrared spectroscopy analysis indicated that the cell wall composition of pulvini is different from that of other axial organs, such as petioles or stems. Moreover, monosaccharide analysis showed that pulvini are pectin-rich organs like developing stems and that the amount of galacturonic acid in pulvini is greater than in developing stems. Computer modeling suggested that pulvinar slits facilitate anisotropic extension in the direction perpendicular to the slits in the presence of turgor pressure. When tissue slices of CMCs were transferred to different extracellular osmotic conditions, pulvinar slits altered their opening width, indicating their deformability. In this study, we thus characterized a distinctive cell wall structure of CMCs, adding to our knowledge of repetitive and reversible organ deformation as well as the structural diversity and function of the plant cell wall.

A mechanical theory of competition between plant root growth and soil pressure reveals a potential mechanism of root penetration

Root penetration into the soil is essential for plants to access water and nutrients, as well as to mechanically support aboveground structures. This requires a combination of healthy plant growth, adequate soil mechanical properties, and compatible plant-soil interactions. Despite the current knowledge of the static rheology driving the interactions at the root-soil interface, few theoretical approaches have attempted to describe root penetration with dynamic rheology. In this work, we experimentally showed that radish roots in contact with soil of specific density during a specific growth stage fail to penetrate the soil. To explore the mechanism of root penetration into the soil, we constructed a theoretical model to explore the relevant conditions amenable to root entry into the soil. The theory indicates that dimensionless parameters such as root growth anisotropy, static root-soil competition, and dynamic root-soil competition are important for root penetration. The consequent theoretical expectations were supported by finite element analysis, and a potential mechanism of root penetration into the soil is discussed.

Elastic shell theory for plant cell wall stiffness reveals contributions of cell wall elasticity and turgor pressure in AFM measurement

The stiffness of a plant cell in response to an applied force is determined not only by the elasticity of the cell wall but also by turgor pressure and cell geometry, which affect the tension of the cell wall. Although stiffness has been investigated using atomic force microscopy (AFM) and Young’s modulus of the cell wall has occasionally been estimated using the contact-stress theory (Hertz theory), the existence of tension has made the study of stiffness more complex. Elastic shell theory has been proposed as an alternative method; however, the estimation of elasticity remains ambiguous. Here, we used finite element method simulations to verify the formula of the elastic shell theory for onion (Allium cepa) cells. We applied the formula and simulations to successfully quantify the turgor pressure and elasticity of a cell in the plane direction using the cell curvature and apparent stiffness measured by AFM. We conclude that tension resulting from turgor pressure regulates cell stiffness, which can be modified by a slight adjustment of turgor pressure in the order of 0.1 MPa. This theoretical analysis reveals a path for understanding forces inherent in plant cells.

Tissue growth constrains root organ outlines into an isometrically scalable shape

Organ morphologies are diverse but also conserved under shared developmental constraints among species. Any geometrical similarities in the shape behind diversity and the underlying developmental constraints remain unclear. Plant root tip outlines commonly exhibit a dome shape, which likely performs physiological functions, despite the diversity in size and cellular organization among distinct root classes and/or species. We carried out morphometric analysis of the primary roots of ten angiosperm species and of the lateral roots (LRs) of Arabidopsis, and found that each root outline was isometrically scaled onto a parameter-free catenary curve, a stable structure adopted for arch bridges. Using the physical model for bridges, we analogized that localized and spatially uniform occurrence of oriented cell division and expansion force the LR primordia (LRP) tip to form a catenary curve. These growth rules for the catenary curve were verified by tissue growth simulation of developing LRP development based on time-lapse imaging. Consistently, LRP outlines of mutants compromised in these rules were found to deviate from catenary curves. Our analyses demonstrate that physics-inspired growth rules constrain plant root tips to form isometrically scalable catenary curves.

Highlighted Article: The dome-shaped outlines of plant root tips converge to a parameter-free catenary curve seen in arch bridges, owing to a constraint from anisotropic and localized tissue growth.

Root shape adaptation to mechanical stress derived from unidirectional vibrations in Populus nigra

While it is known that plant roots can change their shapes to the stress direction, it remains unclear if the root orientation can change as a means for mechanical reinforcement. When stress in form of a unidirectional vibration is applied to cuttings of Populus nigra for 5 min a day over a period of 20 days, the root system architecture changes. The contribution of roots with a diameter larger than 0.04 cm increases, while the allocation to roots smaller than 0.03 cm decreases. In addition to the root diameter allocation, the root orientation in the stem proximity was analyzed by appearance and with a nematic tensor analysis in an attempt to calculate the average root orientation. The significant different allocation to roots with a larger diameter, and the tendency of roots to align in the vicinity of the stress axis (not significantly different), are indicating a mechanical reinforcement to cope with the received strain. This work indicates an adaptive root system architecture and a possible adaptive root orientation for mechanical reinforcement.

Spatio-temporal kinematic analysis of shoot gravitropism in Arabidopsis thaliana

Plant shoots can bend upward against gravity, a behavior known as shoot gravitropism. The conventional quantification of shoot bending has been restricted to measurements of shoot tip angle, which cannot fully describe the spatio-temporal bending process. Recently, however, advanced imaging analyses have been developed to quantify in detail the spatio-temporal changes in inclination angle and curvature of the shoot. We used one such method (KymoRod) to analyze the gravitropism of the Arabidopsis thaliana inflorescence stem, and successfully extracted characteristics that capture when and where bending occurs. Furthermore, we implemented an elastic spring theoretical model and successfully determined best fitted parameters that may explain typical bending behaviors of the inflorescence stem. Overall, we propose a data-model combined framework to quantitatively investigate shoot gravitropism in plants.

Laser micromarking technique in studying the negative gravitropism in pea stem

A laser micromarking technique on plant epidermis was developed to study how a plant can reduce the stress in bending behavior by controlling the growth and morphogenesis. The negative gravitropism in a pea seedling (Pisum sativum L.) was discussed based on the time-dependent displacement of laser marking points which were formed by spatially-selective laser ablation of the cuticle layer that covers the outer surface of a plant. The elongation of the stem in the horizontal direction was remarkable in the first half of the gravitropism. The elongation percentages of the stem length between laser-marking points at around upper surface, middle, and bottom surface were evaluated to be 2.57, 4.87, and 7.70%, respectively. The characteristic feature of the stem bending in gravitropism is the elongation even at the upper surface region, that is, inside of the bending. This is a different feature from cantilever beams for structural materials like metals and polymers, where the compression of the upper surface and elongation of the bottom surface are caused by bending. Another laser micromarking technique was developed to improve the resolution of a dot-matrix pattern by fluorescent material transfer to a plant through a masking film with a micro-hole matrix pattern. Similar time-dependent displacement behavior was observed for a fluorescent dot-marked stem showing a feedback control loop in the mechanical optimization. These results suggested that plants solve the problem of the stress in stem bending through growth. The laser micromarking is an effective method for studying the mechanical optimization in plants.

Robust organ size requires robust timing of initiation orchestrated by focused auxin and cytokinin signalling

Organ size and shape are precisely regulated to ensure proper function. The four sepals in each Arabidopsis thaliana flower must maintain the same size throughout their growth to continuously enclose and protect the developing bud. Here we show that DEVELOPMENT RELATED MYB-LIKE 1 (DRMY1) is required for both timing of organ initiation and proper growth, leading to robust sepal size in Arabidopsis. Within each drmy1 flower, the initiation of some sepals is variably delayed. Late-initiating sepals in drmy1 mutants remain smaller throughout development, resulting in variability in sepal size. DRMY1 focuses the spatiotemporal signalling patterns of the plant hormones auxin and cytokinin, which jointly control the timing of sepal initiation. Our findings demonstrate that timing of organ initiation, together with growth and maturation, contribute to robust organ size.

A mathematical model explores the contributions of bending and stretching forces to shoot gravitropism in Arabidopsis

Plant shoot gravitropism is a complex phenomenon resulting from gravity sensing, curvature sensing (proprioception), the ability to uphold self-weight and growth. Although recent data analysis and modelling have revealed the detailed morphology of shoot bending, the relative contribution of bending force (derived from the gravi-proprioceptive response) and stretching force (derived from shoot axial growth) behind gravitropism remains poorly understood. To address this gap, we combined morphological data with a theoretical model to analyze shoot bending in wild-type and lazy1-like 1 mutant Arabidopsis thaliana. Using data from actual bending events, we searched for model parameters that minimized discrepancies between the data and mathematical model. The resulting model suggests that both the bending force and the stretching force differ significantly between the wild type and mutant. We discuss the implications of the mechanical forces associated with differential cell growth and present a plausible mechanical explanation of shoot gravitropism.

Heterogeneity and Robustness in Plant Morphogenesis: From Cells to Organs

Development is remarkably reproducible, producing organs with the same size, shape, and function repeatedly from individual to individual. For example, every flower on the Antirrhinum stalk has the same snapping dragon mouth. This reproducibility has allowed taxonomists to classify plants and animals according to their morphology. Yet these reproducible organs are composed of highly variable cells. For example, neighboring cells grow at different rates in Arabidopsis leaves, sepals, and shoot apical meristems. This cellular variability occurs in normal, wild-type organisms, indicating that cellular heterogeneity (or diversity in a characteristic such as growth rate) is either actively maintained or, at a minimum, not entirely suppressed. In fact, cellular heterogeneity can contribute to producing invariant organs. Here, we focus on how plant organs are reproducibly created during development from these highly variable cells.

Clones of cells switch from reduction to enhancement of size variability in Arabidopsis sepals

Organs form with remarkably consistent sizes and shapes during development, whereas a high variability in growth is observed at the cell level. Given this contrast, it is unclear how such consistency in organ scale can emerge from cellular behavior. Here, we examine an intermediate scale, the growth of clones of cells in Arabidopsis sepals. Each clone consists of the progeny of a single progenitor cell. At early stages, we find that clones derived from a small progenitor cell grow faster than those derived from a large progenitor cell. This results in a reduction in clone size variability, a phenomenon we refer to as size uniformization. By contrast, at later stages of clone growth, clones change their growth pattern to enhance size variability, when clones derived from larger progenitor cells grow faster than those derived from smaller progenitor cells. Finally, we find that, at early stages, fast growing clones exhibit greater cell growth heterogeneity. Thus, cellular variability in growth might contribute to a decrease in the variability of clones throughout the sepal.

Summary: Growth analyses of Arabidopsis sepals identify a tipping point in organ development, at which clones of cells change their growth pattern from size uniformization to size variability enhancement.

Extracting Subcellular Fibrillar Alignment with Error Estimation: Application to Microtubules

The order and orientation of cortical microtubule (CMT) arrays and their dynamics play an essential role in plant morphogenesis. To extract detailed CMT alignment structures in an objective, local, and accurate way, we propose an error-based extraction method that applies to general fluorescence intensity data on three-dimensional cell surfaces. Building on previous techniques to quantify alignments, our method can determine the statistical error for specific local regions, or the minimal scales of local regions for a desired accuracy goal. After validating our method with synthetic images with known alignments, we demonstrate the ability of our method to quantify subcellular CMT alignments on images with microtubules marked with green fluorescent protein in various cell types. Our method could also be applied to detect alignment structures in other fibrillar elements, such as actin filaments, cellulose, and collagen.

Muscle pathology in Marinesco-Sjogren syndrome: a unique ultrastructural feature

The light- and electron-microscopical findings in the skeletal muscle of a patient with Marinesco-Sjogren syndrome (MSS) are presented. Muscle biopsy specimens showed myopathy with slightly dystrophic changes including variation in fiber size, muscle fiber necrosis, regeneration and rimmed vacuole formation. Fiber type analysis with myosin ATPase staining showed a mild increase in type 2C fibers. Electron microscopy revealed autophagic vacuoles with numerous myeloid bodies, and a unique dense membranous structure associated with nuclei. We consider that this unique membranous structure is an important feature in the muscle pathology of MSS.

A case of carbamylphosphate synthetase-I deficiency associated with secondary carnitine deficiency--L-carnitine treatment of CPS-I deficiency

We describe a male infant with congenital hyperammonaemia due to partial carbamylphosphate synthetase-I (CPS-I) deficiency. At 21 days of age, he had convulsions and at 53 days of age hyperammonaemic coma. Therapy with sodium benzoate, L-arginine, essential amino acids, L-carnitine and peritoneal dialysis lowered the blood ammonia levels, and his clinical manifestations improved. The CPS-I activity in liver tissue obtained by open biopsy was about 25.6% of normal values. The serum and urine free carnitine levels in the patient decreased during the hyperammonaemic crisis and were low at 7 months of age. After oral administration of L-carnitine (10 mg/kg per day) at 7 months of age, the mean blood ammonia levels decreased significantly, accompanied by an increase in serum and urine free carnitine levels. We propose the use of L-carnitine therapy to prevent secondary carnitine deficiency in patients with CPS-I deficiency as well as ornithine transcarbamylase (OTC) deficiency.

Immunoglobulin A antibody response to respiratory syncytial virus structural proteins in colostrum and milk

Immunoglobulin A (IgA) antibody response to respiratory syncytial virus (RSV) structural proteins in colostrum and milk was investigated by a radioimmunoprecipitation assay. By using [35S]methionine-labeled RSV-infected HEp-2 cells and antiserum to human IgA as the capture antibody, IgA antibody responses to large glycoprotein, fusion protein, nucleoprotein, phosphoprotein, and matrix protein were demonstrated in colostrum and milk. The IgA antibody response was mainly directed against fusion protein, whereas IgA activity against matrix protein was more variable and was not comparable to the antibody responses to other structural proteins. Maternal mammary IgA response after RSV infection in the infant was monitored in four cases, and the appearance of anti-RSV IgA activity against several RSV structural proteins was observed in convalescent-stage milk samples of two mothers in whom RSV infection was demonstrated.

Antigenic variation of human RSV strains isolated in Japan

Antigenic variations of respiratory syncytial virus (RSV) strains were analyzed using a collection of nine, seven, two, and one monoclonal antibodies (MAbs), respectively, raised against the fusion protein (F), large glycoprotein (G), nucleoprotein (NP), and phosphoprotein (P) components of the Long strain of RSV. Competitive binding assay by these MAbs demonstrated eight, four, and two distinct epitopes on F, G, and NP components, respectively. Comparison of prototype Long with ten field strains isolated in Sapporo, Japan, during a 9-year period from 1980 to 1988 by radioimmunoprecipitation (RIP), immunofluorescence (IF), and enzyme-linked immunosorbent assay (ELISA) test revealed four different patterns of reaction to these MAbs. Thus, prototype Long reacted to all 19 MAbs. Six field strains have shown a different reactivity to one of nine anti-F and to one of seven anti-G antibodies (subgroup A). Three of the remaining isolates failed to react with three of nine anti-F and with all of seven anti-G antibodies (subgroup B). One strain (58-104) isolated in 1983 was similar to subgroup A except for a lack of reaction with two anti-G antibodies. All field strains reacted with two anti-NP and one anti-P antibodies. The numbers of altered epitopes in subgroup A were 1/8 and 1/4; in subgroup B, 3/8 and 4/4; and in 58-104, 1/8 and 2/4 on the F and G components, respectively. No other variations have been observed among field isolates tested.

Complementation analysis of beta-galactosidase deficiency by means of histochemical method

Cultured skin fibroblasts from 4 beta-galactosidase-deficient patients with different clinical features were hybridized and beta-galactosidase activities were measured using 4-methylumbelliferyl (4MU)-derivate and by means of indigogenic method. Compared with the assays of beta-galactosidase activity using 4MU-derivate, more clear-cut evidence was obtained in the indigogenic method for a judgement of complementation.

Comparative enzymology of eleven acid hydrolases in cultured amniotic fluid cells, skin fibroblasts and embryonic lung fibroblasts, and the respective changes with the increasing age of the cell cultures

Assay conditions were studied for eleven lysosomal enzymes (beta-D-galactosidase, alpha-D-mannosidase, beta-hexosaminidase, beta-D-glucuronidase, alpha-D-galactosidase, alpha-D-glucosidase, arylsulfatase, beta-D-glucosidase, alpha-L-fucosidase, alpha-D-neuraminidase and alpha-L-iduronidase) in cultured amniotic fluid cells (CAFC), cultured skin fibroblasts (CSF) and cultured embryonic lung fibroblasts (CELF), and the properties of the enzymes were compared among these cultured cells. In addition, changes in these enzymes from the three cell types were investigated between 4-6 earlier passages and 24-26 later passages. With the exception of alpha-D-glucosidase, alpha-D-neuraminidase and alpha-L-fucosidase, all enzymes assayed for the 4-6 earlier passages and the 24-26 later passages had the same Km values and the same pH optima, and were also unchanged with the increasing age of cell cultures, with regard to their points. The specific activities of beta-D-glucuronidase, arylsulfatase, alpha-D-glucosidase and beta-D-glucosidase for the 4-6 earlier passages increased significantly with development, though no change was observed with development in the specific activities of other enzymes. Variations were observed between the levels of these enzymes in the three cell types with the increasing age of cell cultures, such as increases in some, decreases in others and no change in still others.

Heparan sulfate and dermatan sulfate from the liver of a patient with Hurler syndrome: high performance liquid chromatography of their degradation products after incubation with alpha-L-iduronidase-deficient fibroblasts

Using a high performance liquid chromatography method, degradation products of heparan sulfate (HS) and dermatan sulfate (DS) were investigated after incubation of control and alpha-L-iduronidase-deficient fibroblasts with HS or DS. Characteristic elution profiles of the degradation products were obtained from the respective alpha-L-iduronidase-deficient fibroblasts. Moreover, alpha-L-iduronidase in control fibroblasts was resolved into two distinct components, forms A and B, on DEAE-cellulose column chromatography. Form A alpha-L-iduronidase could degrade HS, but not DS. Conversely, form B alpha-L-iduronidase could not degrade HS, but could degrade DS.

Properties of alpha-L-iduronidase in cultured skin fibroblasts from alpha-L-iduronidase-deficient patients

On DEAE cellulose column chromatography, alpha-L-iduronidase in cultured skin fibroblasts was resolved into two distinct components, forms A and B. They had similar Km values for 4-methylumbelliferyl-alpha-L-iduronide, but differed in pH optima and thermal stability. Form B was more heat-stable than form A. Residual alpha-L-iduronidase activity in Hurler fibroblasts was heat-stable, while that in Scheie fibroblasts was heat-labile, and moreover, that in Hurler-Scheie compound fibroblasts lay intermediate between Hurler and Scheie syndromes. These findings demonstrated that Hurler syndrome, Scheie syndrome and Hurler-Scheie compound were enzymatically distinguishable.

Activities of sulfatases for the degradation of acidic glycosaminoglycans in cultured skin fibroblasts from two siblings with multiple sulfatase deficiency

Cultured skin fibroblasts from two siblings with multiple sulfatase deficiency (MSD) were assayed for the activities of sulfatases known to degrade acidic glycosaminoglycans (AGAG). There were iduronate sulfatase, arylsulfatase B, heparan sulfate (HS) sulfatase, N-acetylgalactosamine-6-sulfate sulfatase, HS-derived N-acetylglucosamine-6-sulfate sulfatase, and two keratan sulfate (KS)-derived N-acetylglucosamine-6-sulfate sulfatases. The activities of sulfatases required for the degradation of HS were reduced to a greater extent than those for the degradation of dermatan sulfate (DS), and those of sulfatases associated with basic defect of Morquio disease type A were moderately decreased or normal. On the other hand, urinary excretion of AGAG in both patients was increased about 10-fold compared to controls, and especially, the excretion of HS and DS was increased about 150-fold and 50-fold, respectively. Keratan sulfate was not detected. The results suggest that in patients with MSD the degradation of HS might be affected to a greater extent than that of DS.

Characterization of keratan sulfate isolated from liver affected by Morquio syndrome

Chemical structures of keratan sulfate (KS) isolated from the liver affected by Morquio syndrome type A (classical type) were investigated. In the KS from Morquio syndrome liver, the molar ratios of hexose, total sulfate, N-sulfate and sialic acid to hexosamine were 5.07, 0.90, 0.18 and 0.08, respectively, and about 10% of hexosamine consisted of galactosamine. The KS resulted in a production of oligosaccharides of relatively larger size after digestion with keratanase, as compared with bovine corneal KS. These findings strongly suggest that KS accumulated in the liver affected by Morquio syndrome may be derived from bony KS.

[Clinical studies on cefadroxil in the field of pediatrics]

The newly developed cefadroxil (CDX) dry syrup in a mean daily dose of 32.9 mg/kg t.i.d. or q.i.d. was administered to children for a period of 8 days on the average; viz. a total of 64 cases consisting of 39 cases of tonsillitis, 2 of tonsillitis complicated with otitis media, 1 of bronchitis, 1 of pneumonia, 14 of scarlet fever, and 7 of urinary tract infections; and its clinical and bacteriological effects, and adverse reactions were examined, leading to the following results. 1. The clinical effects were "good" or "excellent" in any of 39 cases of tonsillitis, 2 of tonsillitis complicated with otitis media, 1 of pneumonia, 14 of scarlet fever, and 7 of urinary tract infections, and "fair" only in a case of bronchitis, showing the high efficacy of 98.4%. 2. The clinical effects by daily dose were compared only in the great cases of tonsillitis between the 2 daily dose groups of 30 mg/kg or below and 31 to 40 mg/kg, and both groups showed "good" or "excellent" results, but the latter group revealed that the excellent rate was greater by 20.8% than that of the former group. 3. The frequency of daily administration was 3 times or 4 times and the cases of 4 times administration were few in any disease. In comparison of clinical effects between the 3 times group and the 4 times group in the whole cases, no significant difference was observed between both groups but it is desirable to make the 4 times administration in view of the pharmacokinetics. 4. The bacteriological effects could be judged in 15 cases, namely bacteria were eradicated in 14 cases and unchanged in 1 case, showing a good result of the eradication rate as 93.3%. 5. No adverse reaction was observed and the laboratory test values showed eosinophilia in 7 cases (15.9%) and abnormal elevations of GPT in 1 case (4.5%), of GOT and GPT in 2 case (9.1%), of LDH in 1 case (4.8%) and of BUN in 1 case (4.8%), but 4 of the 7 cases with eosinophilia seemed attributable to underlying diseases or objective diseases. From the above it can be said that this preparation is a useful drug in mild bacterial diseases.

A case of pyruvate carboxylase deficiency with later prenatal diagnosis of an unaffected sibling

A severely mentally retarded infant with congenital lactic acidosis due to pyruvate carboxylase deficiency is reported. The patient suffered from vomiting and convulsions soon after birth and developed severe mental and motor retardation at 3 months of age. The persistent elevation of pyruvate and lactate in both blood and cerebrospinal fluid and hyperalanaemia suggested an impairment of pyruvate oxidation. The enzyme activities of pyruvate carboxylase in both liver tissues and cultured skin fibroblasts of the patient revealed values of about 5% of controls. However, pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase activities in liver tissues were within normal limits. The patient had no response to administration of large doses of thiamine, lipoic acid and biotin, clinically and biochemically. A prenatal diagnosis was performed in the second pregnancy and the pyruvate carboxylase activities of the cultured amniotic fluid cells obtained by amniocentesis were within normal limits.

A new type of hypermethioninemia in neonates

Eleven hypermethioninemic patients were found by mass screening tests of neonates. Three of these had persistent hypermethioninemia while in the others it was transient. Serum concentrations of methionine were constantly higher than those of controls, especially in the persistent group. The enzyme activities of methionine adenosyltransferase in the liver tissues of both groups of patients were within normal limits. Serum concentrations of total folate in the persistent group were strikingly elevated and fatty degeneration of the liver tissues was a constant feature. It improved after several months under a low-methionine diet. The hypermethioninemia reported here is not associated with any clinical or biochemical finding reported previously.

Acidic glycosaminoglycans and gangliosides in the brains from four patients with genetic mucopolysaccharidosis

Acidic glycosaminoglycans (GAGs) and gangliosides were analyzed in the brains from control fetuses, fetal Hurler syndrome, control children and three patients affected by genetic mucopolysaccharidosis (Hurler, Hunter and Morquio syndromes). GAGs contents in the brains from patients with Hurler and Hunter syndromes were approximately 1.5-3.0-fold greater as compared with those controls, and most of the GAGs were much more degraded than those from controls. Dermatan sulfate (DS), which was not identified in the control brains, comprised about 20--40% of the total GAGs. On the other hand, GAGs content and molecular weight distribution in the brain from the patient affected by Morquio syndrome were similar to those in the control brains. GAGs content in the brain from fetal Hurler syndrome was also 2.0-fold greater and DS, which was not detected in the control fetal brains, comprised 1.6% of the total GAGs. However, the molecular weight distribution of the GAGs was similar to those of the control fetal brains. The total amount of the brain gangliosides in all patients assayed here was similar to those in the control brains. However, a greater amount of GM1- and Gm2-gangliosides was observed in the brains from patients with Hurler and Hunter syndromes.

A case of type 2 Gm1-gangliosidosis with long survival

An 11-year-old boy with type 2 GM1-gangliosidosis was presented, providing further evidence for the clinical and biochemical heterogeneity of the disease. The patient had several characteristics of type 2 GM1-gangliosidosis, but was different from so-called typical type 2 GM1-gangliosidosis from the point of view of survival and the degree of GM1-ganglioside accumulation. GM1-gangliosidosis was diagnosed by absence of beta-galactosidase activity in leukocytes and the parents had the enzyme levels of heterozygotes. However, the amount of the brain GM1-ganglioside was accumulated to a less degree in comparison with that of typical type 2 GM1-gangliosidosis, though the activity of GM1-beta-galactosidase in the brain was deficient to the same degree as in the typical case.

Vitamin D dependent rickets: decreased sensitivity to 1,25-dihydroxyvitamin D

A patient with vitamin D dependent rickets with decreased sensitivity to 1,25-Dihydroxyvitamin D was observed. She suffered from bone pain of two years duration beginning at 12 years of age and was found to be suffering from hypocalcemia, secondary hyperparathyroidism and osteomalacia. Laboratory findings revealed normal serum 25-hydroxyvitamin D (27 ng/ml) and markedly elevated serum 1,25-dihydroxy-vitamin D (131.9 pg/ml). The hypocalcemia was refractory in spite of administration of 25,000 units of vitamin D2, but therapy with high doses of oral la-hydroxyvitamin D3 resulted in significant elevation of the serum calcium level. The clinical findings and course of the patient's disease were quite different from those of other patients with vitamin D dependent rickets reported by other authors.

Acidic glycosaminoglycans in liver from five patients with mucopolysaccharidosis and mucolipidosis

Content, composition and molecular weight distribution of acidic glycosaminoglycans (GAGs) were determined in liver from five patients with genetic lysosomal storage diseases (Hurler syndrome, Hunter syndrome of severe type, Morquio syndrome, GM1-gangliosidosis type II and I-cell disease). There was a 30- to 40-fold increase in GAGs content of liver from patients with Hurler and Hunter syndromes. The GAGs accumulated in the livers consisted mainly of heparan sulfate and dermatan sulfate, and had a much lower molecular weight than those from control liver. The major GAG accumulated in liver from Morquio syndrome was keratan sulfate, which was not found in the livers from control and other patients, and chondroitin-6-sulfate was also increased. The content and the composition of liver GAGs from GM1-gangliosidosis and I-cell disease were similar to those of control liver. However, there was about a 33-fold increase in the amount of hexose on the liver GAGs from GM1-gangliosidosis. A molar ratio of sialic acid to hexosamine was 1.35 for the liver GAGs from I-cell disease and that of hexose to hexosamine was 8.47, while they were 0.46 and 2.32, respectively, for the control liver.

A new transport interaction of dibasic amino acids and citrulline in human kidney

The oral loading tests of lysine in 9 healthy men and the intravenous loading tests of lysine, ornithine and arginine in 3 healthy men were carried out. The results indicated that the membrane transport system of citrulline in the human kidney was clearly inhibited by dibasic amino acids, lysine, ornithine, and arginine.

[Laboratory and clinical evaluation of cefoxitin in children (author's transl)]

Pharmacokinetics of cefoxitin, a new injectable semisynthetic-cephamycin, was studied in 12 healthy children and also was studied cerebrospinal fluid levels in 1 patient with bacterial meningitis received 44.5 mg/kg of cefoxitin and thoracic fluid levels in 2 patients were measured. Cefoxitin was administered intravenously to 50 patients with various types of infections an average dose of 130 mg/kg/day for an average of 9 days. The results were as follows: 1. Favorable plasma levels were obtained comparing with those off conventional injectable cephalosporins after 15 mg/kg and 25 mg/kg of cefoxitin for one shot intravenous injection. The half lives of cefoxitin in the plasma were about 15.9 minutes up to 1 hour and 25.5 minutes up to 2 hours after an intravenous administration of cefoxitin at a dose of 15 mg/kg, and while, those were 15.9 minutes and 27.5 minutes after an intravenous administration of cefoxitin at a dose of 25 mg/kg, respectively. 2. Cefoxitin was excreted with high concentration up to 2 hours after the administration and thereafter, urinary concentration of cefoxitin declined rapidly with the lapse of time. The time course urinary concentration reflected those of plasma levels. Approximately 94.7% and 90.6% of dosed cefoxitin were recovered in the urine for 6 hours after the administration at the dose of 15 mg/kg and 25 mg/kg, respectively. 3. The cerebrospinal fluid levels of cefoxitin were only determined in a patient of bacterial meningitis. Therefore, further study should be performed. 4. The thoracic fluid levels with 2 patients were higher than cerebrospinal fluid levels. 5. Among the 50 patients with various infections, cefoxitin was clinically effective in 84% and bacterial response in 87%. 6. As adverse reactions, in total 79 patients included exclusive 29 patients, diarrhea occurred in 1 patient, sweating and cough in 1 patient, rash with fever in 4 patients, vascular pain in 2 patients, and leukopenia was observed in 1 patient, eosinophilia in 1 patient, and increase of GOT and LDH were observed in each 2 patients. The other adverse reactions were not experienced.

Uridine diphosphate galactose 4-epimerase deficiency

A case of uridine diphosphate galactose (UDP-Gal) 4-epimerase deficiency was discovered by mass screening of newborn infants. UDP-Gal 4-epimerase activity of red blood cells from the patient was found to be remarkably low, i.e., 7.5% of the level in normal controls at comparable ages. The parents showed intermediate values between those of the patient and controls. The enzyme activity in a specimen of liver tissue obtained from the patient by needle biopsy revealed a normal value. Subsequently, two other families with the condition were found by mass screening and these individuals were found to be heterozygotes.

Prenatal diagnosis of Hurler's syndrome--biochemical studies on the affected fetus

A prenatal diagnosis of Hurler's syndrome was made in a pregnancy at risk in a family with two affected children. The fetus was diagnosed as having Hurler's syndrome on the basis of a deficiency of alpha-L-iduronidase in the cultured amniotic cells. The glycosaminoglycans (GAG) content in the supernatant of the amniotic fluid was increased about 1.5 fold compared with that in the control, and increases of heparan sulfate and dermatan sulfate were observed on electrophoresis. The diagnosis could be confirmed by the deficiencies of alpha-L-iduronidase in the liver and brain from the affected fetus. GAG content in the liver from the affected fetus was increased approximately 10 fold as compared with that in the control fetal liver, and most of the GAG were degraded. The GAG content was observed to be increased two fold in the brain, and dermatan sulfate, which was not detected in normal fetal brain, was identified. beta-Galactosidase activities in the affected liver and brain were decreased to 30-50% of the control, and an altered hexosaminidase A was also observed in the liver.

[Treatment of whooping cough and whooping cough syndrome by cefoperazone (author's transl)]

Clinical trial of cefoperazone (CPZ) for the treatment of whooping cough and whooping cough syndrome was performed and the following results were obtained. 1) In 18 cases suffering from whooping cough, CPZ was given 47 approximately 106 mg/kg/day (average 72 mg/kg/day) by intravenous route. The clinical efficacy rates judged by doctors in charge were 44% on the 3 rd day, 75% on the 7 th day, 86% on the period day. And in these cases, the clinical efficacy rates judged by committee members were 56%, 83% and 86%. 2) In 6 cases diagnosed as whooping cough syndrome, CPZ was given 49 approximately 96 mg/kg/day (average 59 mg/kg/day) by the same route. The clinical efficacy rates judged by doctors in charge were 67% on the 3 rd day, 80% on the 7 th day and 75% on the period day. And in these cases, those judged by committee members were 83%, 80% and 100%. 3) In 1 case, Bordetella pertussis was searched and showed 0.012 mcg/ml of MIC. It was eliminated on the 1 st day after administration. 4) Doctors in charge judged the utility of CPZ for whooping cough. Twelve cases were useful and 6 cases were slightly useful. 5) No side effects were observed except for elevation of GOT and LDH. These results suggest that CPZ might be useful drug against whooping cough.

Activities of N-acetylgalactosamine-6-sulfate sulfatase in liver from two sisters with morquio syndrome

A 6-sulfated tetrasaccharide obtained by digesting chondroitin-6-sulfate with testicular hyaluronidase was used as a substrate for the determination of N-acetylgalactosamine-6-sulfate sulfatase activity. The activity was not detected in liver obtained from the elder sister with clinically classic Morquio syndrome and 4.7% of the control in liver from the younger sister with the same disease.

Identification of keratan sulfate in liver affected by Morquio syndrome

Glycosaminoglycan content, composition and molecular weight were determined in liver obtained from a patient with Morquio syndrome (Mucopolysaccharidosis IV). There was about a four-fold increase in glycosaminoglycan content (as hexosamine) of the affected liver as compared to the control liver. The major glycosaminoglycan accumulated in the liver was keratan sulfate, which was not found in the control liver. Chondroitin sulfates, especially chondroitin 6-sulfate, were also increased. Heparan sulfate isolated from the liver of a patient with Morquio syndrome was structurally different to that from control liver, and the glycosaminoglycans from Morquio syndrome were of a much lower molecular weight than those from control.

Prenatal diagnosis of GM1-gangliosidosis: biochemical manifestations in fetal tissues

A prenatal diagnosis of GM1-gangliosidosis was made in a pregnancy at risk, on the basis of a deficiency of beta-galactosidase activity demonstrated in cultured amniotic fluid cells. Biochemical analyses were performed in the aborted fetus. GM1-ganglioside beta-galactosidase activity was reduced to 1% of the control value in both the brain and liver of the affected fetus. Lamellar bodies suggestive of membranous cytoplasmic bodies were found in cells of basal ganglions, while the accumulation of GM1-ganglioside in the brain was not remarkable.

Atypical Hurler syndrome without alpha-L-iduronidase deficiency

Three atypical patients with clinical and laboratory findings of Hurler syndrome, but without alpha-L-iduronidase deficiency, are described. Clinical features included characteristic facies, mental retardation, corneal clouding, dysostosis multiplex, restriction of joint mobility, and hepatosplenomegaly. Excessive amounts of chondroitin sulfate B and heparitin sulfate were excreted in the urine. alpha-L-Iduronidase activities in leucocytes and liver tissues were within the normal range or somewhat elevated.