Intussusception is a common cause of intestinal obstruction in infants aged 6-18 months. However, intussusception in preterm neonates (IPN) is an exceedingly rare disorder. The etiology of IPN remains unclear, but common prenatal injuries, such as those causing intestinal hypoxia/hypoperfusion, dysmotility, and strictures, have been proposed as possible contributing factors.
View Article and Find Full Text PDFPurpose: Testicular torsion requires emergency surgery; thus, prompt and correct diagnosis is very important. Ultrasound with color Doppler is usually the first-choice modality for diagnosis; however, skill and experience are required for confident diagnosis. Recently, contrast-enhanced ultrasound for the diagnosis of testicular torsion has been reported, but there have been only a few reports.
View Article and Find Full Text PDFBackground: Pleuropulmonary blastoma (PPB) is an extremely rare and malignant pediatric lung tumor. Purely cystic PPB has a more favorable prognosis than solid PPB, but may be difficult to distinguish from a certain type of "benign" congenital pulmonary airway malformation before and during surgery. The influence of tumor rupture on long life prognosis has not been clarified in detail.
View Article and Find Full Text PDFPurpose: Torsion of the appendix testis or epididymis is a cause of acute scrotum in children. Ultrasonography with color Doppler is the first-choice modality for diagnosis. However, this method requires skill and experience to make a diagnosis with confidence.
View Article and Find Full Text PDFBackground: Extremely low birth weight (< 1000 g) still influences postsurgical prognosis in the neonatal and infantile periods. Additionally, the life expectancy of neonates with trisomy 18 is extremely poor owing to various comorbidities. Therefore, it takes courage to perform laparotomy for the purpose of treatment of congenital multiple intestinal atresia in a baby with an unpredictable life prognosis.
View Article and Find Full Text PDFBackground: Thoracotomy with posterolateral incision (PLI) is commonly used for surgical repair of patent ductus arteriosus (PDA) in extremely low birth weight (ELBW) infants. Some reports have described thoracotomy for PDA using an axillary skin crease incision (ASCI) in consideration of cosmetic problems such as surgical wounds and thoracic deformities, but the details remain unclear.
Methods: In this study, we performed clipping ligation by thoracotomy with ASCI for ELBW infants with PDA from 2011 to 2015 for the purpose of improving cosmetic results, and retrospectively compared the results with those for conventional PLI cases performed from 2016 to 2020.
Background: Necrotizing fasciitis in neonates is a rare and life-threatening infection involving necrosis of the skin, subcutaneous tissues, deep fascia, and sometimes underlying muscles, with a fulminant course and high mortality rate. Necrotizing fasciitis with gas gangrene related to infection of a peripherally inserted central catheter is very rare.
Case Presentation: The patient was a full-term female neonate born by vaginal delivery.
Background: Repair of esophageal atresia is usually performed through the right thoracic cavity. However, when the upper pouch of the esophagus and tracheoesophageal fistula (TEF) is located in the thoracic inlet and completely on the left side of trachea, it is difficult to dissect and anastomose the esophagus through the right thoracic cavity. We present a case of esophageal atresia, with the esophageal upper pouch located high and completely on the left side of trachea, successfully repaired via the median sternotomy approach.
View Article and Find Full Text PDFHirschsprung disease (HSCR) is characterized by congenital absence of enteric neurons in distal portions of the gut. Although recent studies identified Schwann cell precursors (SCPs) as a novel cellular source of enteric neurons, it is unknown how SCPs contribute to the disease phenotype of HSCR. Using Schwann cell-specific genetic labeling, we investigated SCP-derived neurogenesis in two mouse models of HSCR; Sox10 haploinsufficient mice exhibiting distal colonic aganglionosis and Ednrb knockout mice showing small intestinal aganglionosis.
View Article and Find Full Text PDFMutations of the gene encoding the tyrosine kinase causes Hirschsprung's disease (HSCR) and medullary thyroid carcinoma (MTC). Current consensus holds that HSCR and MTC are induced by inactivating and activating RET mutations, respectively. However, it remains unknown whether activating mutations in the gene have adverse effects on ENS development We addressed this issue by examining mice engineered to express RET51(C618F), an activating mutation identified in MTC patients.
View Article and Find Full Text PDFMedullary thyroid carcinoma (MTC) develops from hyperplasia of thyroid C cells and represents one of the major causes of thyroid cancer mortality. Mutations in the cysteine-rich domain (CRD) of the RET gene are the most prevalent genetic cause of MTC. The current consensus holds that such cysteine mutations cause ligand-independent dimerization and constitutive activation of RET.
View Article and Find Full Text PDFUrodele newts have the remarkable capability of organ regeneration, and have been used as a unique experimental model for more than a century. However, the mechanisms underlying regulation of the regeneration are not well understood, and gene functions in particular remain largely unknown. To elucidate gene function in regeneration, molecular genetic analyses are very powerful.
View Article and Find Full Text PDFBackground/purpose: Congenital subglottic stenosis is a rare anomaly caused by thickened cricoid cartilage. We report our surgical techniques, comprising anterior cricoid split (ACS), laryngotracheoplasty (LTP), KTP laser ablation, and application of a tracheal opening retainer (TOR) into the tracheostomy site.
Methods: Nine patients have been treated since 1988.
Purpose: When injured, the adult newt possesses the remarkable capability to regenerate tissues and organs with return of function and physiology. One example is the newt eye, in which regeneration can restore normal vision if the retina or lens has been removed. We wanted to examine how the retinotectal projections regenerate after removal of the brain's optic tectum and establish this animal as a model for retinal projection as well as a central nervous system regeneration model.
View Article and Find Full Text PDFLens regeneration in adult newts is a classic example of how cells can faithfully regenerate a complete organ through the process of transdifferentiation. After lens removal, the pigment epithelial cells of the dorsal, but not the ventral, iris dedifferentiate and then differentiate to form a new lens. Understanding how this process is regulated might provide clues about why lens regeneration does not occur in higher vertebrates.
View Article and Find Full Text PDFLens regeneration in newts occurs exclusively from the dorsal aspect of the iris pigment epithelium. Although the phenomenon has been a paradigm of experimental tissue regeneration, little is understood about how it is initiated and restricted to the dorsal iris. Here we show among various growth factors injected in an intact eye, a single injection of FGF2 specifically caused morphological changes of the iris characteristic of lens regeneration, induced expression of transcription factor genes Pax6, Sox2 and MafB, as well as endogenous Fgf2 in both dorsal and ventral halves, and provoked second lens development only from the dorsal iris.
View Article and Find Full Text PDFWhen a lens is removed from the newt eye, a new lens is regenerated from the pigmented epithelial cells of the dorsal iris, whereas the ventral iris never shows such an ability. It is important to clarify the nature of signaling molecules which act directly on the iris cells to accomplish lens regeneration from the iris and also to gain insight into the mechanism of dorso-ventral difference of the regeneration potential. To examine the effects of exogenous factors, we established an in vitro culture of reaggregates made from dissociated pigmented epithelial cells of dorsal or ventral halves of newt iris.
View Article and Find Full Text PDFDev Growth Differ
October 1995
Genetiç transduction of newt was undertaken in search of conditions allowing high exogenous gene expression in stages from late embryo to larva when regeneration experiments, which are advantageous for this group of animals, are possible. DNA of a β-galactosidase-encoding gene miwZ was injected in the cytoplasm of fertilized eggs in different molecular forms, and its fate and gene expression were studied in individual embryos. When DNA was injected in a linear form, DNA concatemerized quickly and the majority of the exogenous sequences were localized in the nuclear fraction from early gastrula onwards.
View Article and Find Full Text PDFTo investigate the effects of nickel subsulfide (Ni S ) on lens regeneration, Ni S was administered to the lentectomized newt eye by a single injection into the eye chamber. Lens regeneration was inhibited in the early stage of regeneration with about 60% of the treated eyes after 25 days, while all control eyes had a regenerating lens. The size of the regenerating lens in the treated eyes was the same as in controls.
View Article and Find Full Text PDFChanges in the fine structure, the location and the number of stacks of annulate lamellae during progesterone-induced maturation of oocytes of Xenopus were determined by electron microscopy. longitudinal sections of full-grown oocytes, about 260 stacks of annulate lamellae were observed with marked concentration in the subcortical layer, particularly in the vegetal hemisphere. After exposure to.
View Article and Find Full Text PDFDev Growth Differ
January 1975
The outermost cell layer of the animal half of the newt blastula (Triturus pyrrhogaster) was examined to investigate intercellular junctions by transmission and scanning electron microscopy. A unique structure is observed at the terminal region of the intercellular junction. The structures are cytoplasmic ridges elevated from the cell surfaces, and their inner part is filled with spaces of various sizes.
View Article and Find Full Text PDFA simple procedure is described for removing the jelly and vitelline membrane of Xenopus laevis embryos. The method is based on the observation that incubation of the embryos in the mixed solution of trypsin and sodium thioglycolate at pH 8.0 causes effective dissolution of these structures.
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