bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estradiol Secretion by Tadpole Ovaries Masculinized by Implanted Capsules of Cyanoketone
Authors: Chih‐Yun Hsu , Nai‐Wen Yu , Hung‐Hai Ku , Li‐Tze Chang , Hwan‐Wun Liu 
Published: January 2005

Female tadpoles of Rana catesbeiana were laparotomized at metamorphic stages XI‐XIII and an empty capsule or one containing cyanoketone (CK), which is an inhibitor of Δ5‐3β‐hydroxysteroid dehydrogenase (Δ5‐3β‐HSD), was implanted intraperitoneally. Ovarian activity of Δ5‐3β‐HSD was examined histochemically 2 months later, estradiol‐17β (E2) secretion by the ovaries was measured by RIA 4 months later and histological changes of the ovaries were examined 6 months later. The Δ5‐3β‐HSD activity of the CK‐treated ovaries was much lower than that of controls. E2 secretion per froglet by CK‐treated ovaries was about one third that of controls (p<0.001). Histological examination showed various degrees of masculinization of the ovaries, about 28% of which were totally transformed into testis‐like structures.As a result of suppressed Δ5‐3β‐HSD activity, dehydroepiandrosterone would have accumulated, resulting in deficient E2 secretion and, therefore, ovarian masculinization. In tadpoles, this effect does not depend on the pituitary, whereas interrenal hyperplasia and hyperactivity do, indicating that interrenal function is not essential for ovarian masculinization. From these findings and our previous results, we suggest that disturbance of steroidogenesis by CK in the ovaries results in their masculinization.
Polarization of the Surface Membrane and Cortical Layer of Sea Urchin Blastomeres, and its Inhibition by Cytochalasin B
Authors: Yazaki Ikuko 
Published: January 2005

Sea‐urchin blastomeres have two domains of the plasma membrane which can be distinguished immunocytochemically. An egg‐surface antibody (anti‐ES), which binds to the membrane of the entire surface region of eggs before cleavage, binds to the membrane of the outer surface region of blastomeres after cleavage, but not to that of the cleavage furrow region or interblastomeric surface region.The anti‐ES binding sites on the egg membrane were chased after cleavage by labeling the egg plasma membrane with FITC conjugated monovalent anti‐ES (FITC‐Fab anti‐ES) before the first cleavage, and then allowing the eggs to cleave. The surface fluorescence increased in intensity in the cleavage furrow region with progress of furrowing, but after completion of the furrowing, the fluorescence became uniform and finally decreased in the interblastomeric surface region.The distributions of pigment granules and NBD‐phallacidin stainable microfilaments in the cortex after completion of furrowing were polarized in the same way as the anti‐ES binding area. As cytochalasin B completely inhibited the polarization in both the surface and cortical layer but colchicine did not, polarization of the anti‐ES binding area was concluded to be due to the post‐cleavage polarized distribution of submembranous microfilaments in the cortical layer.
Subcortical Rotation and Specification of the Dorsoventral Axis in Newt Eggs
Authors: Fujisue Megumi , Sakai Masao , Yamanat Kiyotaka 
Published: January 2005

The specification of the dorsoventral axis in naturally polyspermic eggs of the Japanese newt, Cynops pyrrhogaster, was first examined by studies on the spatial relationship between the dorsal midline of the future body plan and the sperm entrance points (SEPs1). On local insemination, the dorsal blastopore lip was usually found to be formed opposite the SEPs, as in anuran monospermic eggs. Next the movements of the subcortical layer and the cortex were analyzed. “Subcortical rotation” was observed, similar to that of Xenopus laevis eggs with respect to its timing and extent, and its direction was shown to predict the embryonic axis of the eggs. Thus, the dorsoventral axis was concluded to be determined by essentially the same mechanism in the newt as in Xenopus.Owing to their large size and long first cell cycle, newt eggs appear to be suitable material for study of subcortical rotation, but their behavior is unique in that subcortical rotation occurs in only the vegetal hemisphere so that the subcortical layer stretches in the future dorsal side. Studies on the movement of Nile blue spots suggested that the cytoplasm under the cortex in newt eggs consists of two layers.
Ampulla Morphogenesis in Anural and Urodele Molgulid Ascidians
Authors: Bates William R. 
Published: January 2005

Vascular ampulla morphogenesis was studied in two anural‐developing molgulids and one urodeledeveloping molgulid. In all three species, each juvenile developed one longer ampulla (termed the primary ampulla) and several shorter ampullae (termed secondary ampullae). Ampulla growth was accompanied by the formation of contraction rings that moved in a proximal to distal direction. Contraction ring formation was initiated by the epidermal cells situated in the proximal region of each ampulla. The formation of an expanding bubble‐like region within each lumen preceded ring formation. These rings moved at approximately 120 μm/min. Rings were produced for several days until the ampullae retracted towards the body wall.In all three species, hemoblast cells were evident at day 4 within the developing mantle sinus (hemocoel). Ampulla growth was studied by positioning chalk particles on the tunic surface near the tips of ampullae. During the growth phase, chalk particles moved towards the body of the zooid. This report is the first to describe contraction ring formation and the polarized transport of tunic components during ampulla morphogenesis in two anural ascidian species.
In Vivo Study of Vitellogenin‐Gold Transport in the Ovarian Follicle and Oocyte of Xenopus laevis
Authors: Yoshizaki Norio 
Published: January 2005

The transport of injected vitellogenin (VTG)‐gold in the ovarian follicle and developing oocyte in Xenopus is described. The gold particles reached the extracellular spaces of the theca and interfollicular spaces within 1 and 2 hr, respectively, after a tracer injection at 20°C. The tracers moved through channels between the constitutive cells of both the capillary endothelium and the follicle cell layer.Compartments in the peripheral cytoplasm of vitellogenic oocytes at stage IV, which relate to yolk formation, seemed to be segregated as follows: (a) internalization compartment consisting of coated pits and vesicles of the oolemma covering the oocyte “macrovilli”, (b) transport compartment of endosomes and multivesicular endosomes in the oocyte cortex, and (c) crystallization compartment of primordial yolk platelets (PYP) in the sub‐cortical region. The gold particles appeared in the internalization and transport compartments at 3–6 hr after the tracer injection and in the cystallization compartment at 12–18 hr. The VTG, internalized by receptor‐mediated endocytosis, was transferred from coated vesicles to multivesicular endosomes by vesicle‐to‐vesicle fusion. VTG crystallization took place in globular‐shaped PYPs of about 1 μm. At 24 hr after the tracer injection, the gold particles appeared in completely crystallized yolk platelets, most of them clustered in the superficial layer and some integrated into the crystals.
Some Properties of the Hardening Process in Chorions Isolated from Unfertilized Eggs of Medaka, Oryzias latipes
Authors: Masuda Kaori , Murata Kenji , Iuchi Ichiro , Yamagami Kenjiro 
Published: January 2005

Chorions isolated from unfertilized eggs of medaka, Oryzias latipes, harden during incubation with Ca2+ ions (Masuda et al., 1991). In this process, i.e. in vitro Ca2+‐hardening, the amounts of the major proteins of unfertilized egg chorions (83 K, 78 K and 51 K, corresponding to ZI‐1, 2 and 3 of oocyte chorions reported by Hamazaki et al, 1987) decreased and new proteins having molecular weights of 148 K or more appeared. Immunoblotting analysis using anti‐ZI‐1, 2 antisera and anti‐ZI‐3 antisera showed that the 148 K protein was an intermediate formed during polymerization of the original proteins.The mechanism of in vitro Ca2+‐hardening was studied by examining the decrease in ZI‐1, 2, and 3, the formation of 148 K protein, and the change in solubility of chorions in 6% sodium dodecylsulfate‐1% 2‐mercaptoethanol‐15% glycerol‐0.2 M Tris‐HCl (pH 6.8). In vitro Ca2+‐hardening was inhibited at temperatures higher than 70°C and its optimum pH was about 5.5. It was inhibited by neither aminotriazole nor cadaverine. The results suggested that in vitro Ca2+‐hardening was generated by some factor(s) other than ovoperoxidase and transglutaminase.
Reconstruction of Starfish Eggs by Electric Cell Fusion: A New Method of Detect the Cytoplasmic Determinant for Archenteron Formation
Authors: Kiyomoto Masato , Shirai Hiroko 
Published: January 2005

A method of detecting cytoplasm carrying the determinant for archenteron formation in starfish was established. Animal egg fragments (AEFs) which had been severed from the vegetal halves were fused electrically into pairs with fragments prepared from various regions of immature oocytes. It has been previously shown that the vegetal halves are exclusively endowed with the ability to form the archenteron; AEFs alone develop into so‐called permanent blastulae. Eggs thus reconstructed were allowed to develop in order to assess the presence of the determinant in the added fragments. Only AEFs fused with fragments from near the vegetal pole of the oocytes formed the archenteron and developed into bipinnariae and juveniles.Comparison between the inner and outer (including cortex) cytoplasm of small vegetal fragment showed that the outer cytoplasm gave the reconstructed egg a greater ability to form an archenteron than the inner cytoplasm.
Cell Sorting and Chondrogenic Aggregate Formation in Limb Bud Recombinants and in Culture
Authors: Wada Naoyuki , Uchiyama Kohji , Ide Hiroyuki 
Published: January 2005

The cartilage pattern of the developing chick limb changes along the proximal‐distal (PD) axis. It is assumed that these spatial changes are brought about by differences in the cellular properties of distal mesoderm, the progress zone (PZ). To examine whether these differences are actually maintained in the individual cells composing the PZ, we dissociated early (stage 20) and late (stage 25) PZ tissues into single cells, then mixed and recombined them with ectodermal jackets. The recombinants were grafted to limb bud stumps and allowed to develop into limb‐like structures. Early PZ cells were distributed within whole cartilage elements along the PD axis of the limb‐like structures, while cells from late PZ participated only in the formation of distal cartilage elements.A difference in distribution pattern between the cells of early and late PZ in mixed culture was also observed. Cells of early PZ aggregated rapidly in patches and formed cartilage nodules, while the cells of late PZ distributed in regions surrounding these cell aggregates and gradually differentiated to cartilage cells. These results suggest that the cellular properties in the PZ concerning the rate of chondrogenic aggregate formation change during limb bud development, and that this change may relate to the cartilage pattern formation along the PD axis.
Expression of Regeneration‐Associated Antigens in Normal and Retinoid‐Treated Regenerating Limbs of Ambystoma mexicanum
Authors: Koshiba Kazuko , Tamura Koji , Ide Hiroyuki 
Published: January 2005

The expression of two regeneration‐associated antigens in the blastemas of normal and retinoid‐treated regenerating limbs of axolotl (Ambystoma mexicanum) was examined.One antigen, 55C12, which was similar to tenascin in expression pattern and molecular weight profile, was weakly expressed in the perichondrium and tendon of normal limbs. In the regenerating limbs, the amount of 55C12 antigen increased near the amputation site within 7 days and almost all cells of the blastema mesenchyme came to be positive to the antigen at 20 days, although those of epidermis and most stump tissues were negative. When the regenerating limbs were treated with Am80, a synthetic retinoid, which induced proximo‐distal duplication, the expression of 55C12 antigen in the blastema became weak temporarily and was reactivated in the anterior region of the blastema. This expression pattern suggests that the duplicated limb is formed by the preferential growth of this 55C12‐positive anterior blastema region.The other antigen, 117C1, was faintly expressed in the epidermis, dermis, muscle, perichondrium and cartilage of normal limbs, and intensely expressed in the blastema mesenchyme and wound epidermis. The Am80 treatment, however, induced no changes in the expression pattern of 117C1.These results suggest that these antigens may distinguish two different regions of the blastema in normal regeneration and retinoid‐induced duplication.
The Developmental and Morphological Studies on the Neural and Skeletal Abnormalities in the T/btm Tailless Mice
Authors: Fujimoto Atsushi , Wakasugi Noboru , Tomita Takeshi 
Published: January 2005

The crosses, T/+ or T/tw2×btm/btm, give rise to 50% incidence of the tailless mice, development of which was investigated. No difference was seen in external appearance of the embryos at 9 days of gestation. However, some embryos showed fusion of the notochord and the neural tube at the posterior part of the body on the histological examination. The prospective tailless individuals were distinguishable from the normal littermates by the constriction of the root of the tail at 10 days of gestation. Thereafter, they showed several abnormalities such as the poor growth of the posterior part of the body, thinning of the tail and a blood blister at the tail tip or in the lumbosacral region. The abnormal embryos of 11–12 days showed severer abnormalities in the medio‐dorsal area, i.e., the notochord was branched or degenerated at several places and the neural tube was distorted, duplicated or fused with the mesenchyme. All the tailless newborn young had blood blisters or red scars on the dorsal skin at the middle of the lumbosacral region.Histologically, the spinal cord posterior to the lumbosacral level was revealed to be severely distorted or duplicated and completely devoid of the bony vertebrae, and the dorsal blood blister was found to be the meningomyelocele derived from the abnormal development of the spinal cord. Skeletal abnormalities of the tailless young were as follows. The sacral and caudal vertebrae were absent. The cervical vertebrae were mostly normal, but the thoracic and lumbar vertebrae showed several abnormalities such as fusion of the ribs, lack of the vertebral body and vertebral arch.
Nesiritide during extracorporeal membrane oxygenation
Authors: Smith Todd , Rosen David A. , Russo Pierantonio , Berkenbosch John W. , Gustafson Robert A. , Siu Benjamin L. , Rosen Kathleen R. , Tobias Joseph D. 
Published: January 2005

SummaryNesiritide is a recombinant formulation of B‐type natriuretic peptide (BNP). Preliminary experience in the adult population has shown nesiritide to be an effective agent in the treatment of decompensated congestive heart failure (CHF) in adults. Given its physiological effects, it may be an effective agent in other clinical scenarios. We report the use of nesiritide in two infants during extracorporeal membrane oxygenation (ECMO). In one patient, nesiritide in doses up to 0.09 μg·kg−1·min−1 were used to control mean arterial pressure while in the other patient, doses of 0.01–0.03 μg·kg−1·min−1 were used to augment urine output. The potential applications of nesiritide and dosing regimens for this agent in the ECMO population are discussed.
The optimal insertion length of central venous catheter via the femoral route for open‐heart surgery in infants and children1
Authors: SHINOHARA YUKA , ARAI TOSHIMI , YAMASITA MASAO 
Published: January 2005

SummaryBackground:  The recommended insertion length of central venous (CV) catheter via the internal jugular or subclavian vein has been determined in infants and children. However, the insertion length via the femoral vein has not been well‐studied. This study determined the optimal insertion length of CV catheter via the femoral vein.Methods:  Infants and children, who had undergone cardiac catheterization via the right femoral vein, were the subjects of the study. After routine cardiac catheterization, the distance from the femoral puncture site to the third lumbar vertebral body (L3) level, was measured and recorded. The femoral‐L3 length was termed as the optimal insertion length.Results:  This length was measured in 78 infants and children (age: 1–101 months, weight: 3.1–33.8 kg). The body weight of the patient and the length correlated well: the optimal insertion length (cm) = 0.45 × body weight (kg) + 8.13, coefficient of determination (R2) = 0.84.Conclusions:  It has been recommended to place the tip of the catheter below the level of renal veins to avoid blocking free flow of those veins. Therefore, we chose the mid‐point, L3 level as the optimal tip position of the femoral venous catheter. The length derived from the above formula could be used as a guideline for CV catheter insertion via the femoral vein in infants and children.
Estimation of circulating blood volume in infants using the pulse dye densitometry method
Authors: NAGANO KEIKO , KUSAKA TAKASHI , OKUBO KENSUKE , YASUDA SANEYUKI , OKADA HITOSHI , NAMBA MASANORI , KAWADA KOU , IMAI TADASHI , ISOBE KENICHI , ITOH SUSUMU 
Published: January 2005

SummaryBackground:  Estimation of hemodynamics is important for critically ill infants. Pulse dye densitometry (PDD) using indocyanine green (ICG), which enables measurements of circulating blood volume at the bedside, has recently been developed for adults.Methods:  We conducted a basic investigation to determine whether this method can be applied to infants and measured circulating blood volume in 25 infants whose gestational ages ranged from 24 to 40 weeks (median, 32 weeks). At first, to validate the accuracy of measurements, arterial ICG concentrations determined by blood sample measurements were compared using a spectrophotometer ([ICG blood]) and by noninvasive measurement using PDD ([ICG pdd]) in seven infants. Next, blood volumes in 25 infants were estimated by the PDD method.Results:  There was a positive relationships between [ICG blood] and [ICG pdd] (r = 0.913, P < 0.0001). Using Bland Altman analysis, the bias between the two methods was 0.24 ± 0.30 mg·l−1 (95% confidence interval: 0.39–0.09 mg·l−1) and the limits of agreement (2 sd) were −0.36  and 0.84 mg·l−1, respectively. Mean (sd) blood volume was 94.9 ml·kg−1 (24.3). The values obtained by this study are almost the same as previously reported values obtained by using other methods.Conclusions:  PDD using ICG can be used to monitor of hemodynamics in infants.
Ketorolac after congenital heart surgery: does it increase the risk of significant bleeding complications?
Authors: GUPTA ANUJA , DAGGETT CASEY , LUDWICK JOSEPH , WELLS WINFIELD , LEWIS ALAN 
Published: January 2005

SummaryBackground:  The routine use of ketorolac after congenital heart surgery in infants and children is limited by concerns for postoperative bleeding complications. The object of this study was to determine if the use of ketorolac is associated with an increased risk of significant postoperative bleeding after congenital heart surgery in infants and children.Methods:  A retrospective chart review was performed. The exposure of interest was postoperative use of ketorolac after congenital heart surgery in infants and children. The outcome measured was postoperative bleeding requiring surgical exploration. The patients who received ketorolac were compared with an age‐ and diagnosis‐matched comparison group who did not receive ketorolac.Results:  Records of 842 infants and children who underwent congenital heart surgery between July 2001 and October 2002 were reviewed. 94 (11.1%) patients were treated with ketorolac postoperatively. The comparison group consisted of 94 matched subjects selected from the patients that did not receive ketorolac. The mean age of patient in the ketorolac group was 8.5 (±6.1) years. No (0%) patients in the ketorolac group and four (4.2%) patients in the nonketorolac group developed postoperative bleeding requiring surgical exploration. The relative risk for postoperative bleeding that required surgical exploration in the ketorolac group compared with the nonketorolac group was 0.2 (95% CI 0.02–1.67).Conclusions:  The use of ketorolac after congenital heart surgery in infants and children does not significantly increase the risk of bleeding complications requiring surgical exploration.
Topiramate and metabolic acidosis: a case series and review of the literature
Authors: GROEPER KELLY , McCANN MARY ELLEN 
Published: January 2005

SummaryTopiramate is a new anticonvulsant drug recommended for treatment of partial and generalized seizures in children and adults. It has been found to cause a nonanion gap metabolic acidosis in some patients, which is related to carbonic anhydrase inhibition. This adverse reaction is more common in children than adults and is rarely symptomatic. Clinicians need to be aware of this potential side effect especially in children undergoing major surgery. Children who are treated with topiramate should have a careful history taken preoperatively looking for signs of a metabolic acidosis and baseline blood chemistries should be measured prior to surgery to detect an asymptomatic metabolic acidosis.
Longitudinal Study of Changes in Hip Bone Mineral Density in Caucasian and African‐American Women
Authors: Cauley Jane A. , Lui Li‐Yung , Stone Katie L. , Hillier Teresa A. , Zmuda Joseph M. , Hochberg Marc , Beck Thomas J. , Ensrud Kristine E. 
Published: January 2005

Objectives: To determine whether changes in hip bone mineral density (BMD) differ in Caucasian and African American women.Design: Longitudinal study of changes in hip BMD.Setting: Four U.S. clinical centers.Participants: Six thousand seven Caucasian (mean age 73) and 482 African‐American (mean age 75) women enrolled in the Study of Osteoporotic Fractures.Measurements: Total hip and femoral neck BMD were measured an average of 3.5 years apart (Caucasian) and 2.0 years apart (African American). Annual absolute and percentage changes in BMD and bone mineral apparent density (BMAD) were calculated.Results: The multivariate adjusted annual percentage change in BMD was greater in Caucasian than African‐American women at the total hip (−0.574%/y vs −0.334%/y) and femoral neck (−0.515%/y vs −0.203%/y) (both, P<.001). Similar findings were observed for BMAD. The average annualized rate of BMD loss was twice as high in women aged 75 and older as in women younger than 75 in both ethnic groups. The annual percentage loss in femoral neck BMD in nonusers versus hormone therapy users was (−0.57% vs −0.22%) in Caucasians and (−0.35% vs 0.64%) in African Americans (interaction P=.03).Conclusion: The average rate of hip BMD loss is approximately twice as great in Caucasian as African‐American women and increases with age in both groups. The hormonal and biochemical factors that contribute to ethnic differences and the increase in bone loss with advancing age need to be identified.