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N Toran

Publications and source records attributed to N Toran.

At least 19 recordsLinked to original sources
PubMed2005

A histological study of fetoscopic membrane defects to document membrane healing.

OBJECTIVE: To evaluate the rate of spontaneous healing in human fetal membranes after fetoscopy. STUDY DESIGN: Membranes from patients that had undergone fetoscopic interventions and delivered in one of the two treatment centers were included in the study. The membranes were examined macroscopically for any remaining defects and if present, the size of the defect in chorion and amnion was measured. Subsequently, the defect was excised and stained with HE for histological evaluation. Additional immunohistochemical staining was performed with Ki-67, cytokeratin and vimentin. The proliferation index (percentage of proliferating cells) was calculated in amnion and chorion. RESULTS: Nineteen membrane defects were included in the study. The median time interval between invasive procedures and delivery was 60 days (range 3-112). All fetoscopic defects (n=19) could be identified in the gestational sac and in none spontaneous closure had occurred. Proliferation indices as measured by inmunohistochemistry were very low (median 2.8%, range 0-7%) in the chorion and 0% in the amnion. CONCLUSION: No evidence of spontaneous membrane healing was found after fetoscopic procedures, suggesting that the membrane defect normally persists until delivery. Absence of amniotic fluid leakage after invasive procedures may be based on mechanisms other than histologic membrane repair.

Amnion↗
PubMed2002

Pancreatectomy extension in persistent hyperinsulinaemic hypoglycaemia: a new strategy.

INTRODUCTION: Persistent neonatal and infantile hyperinsulinaemic hypoglycaemia (PNHH) is a rare entity which remains to be elucidated but is associated with severe lesions in paediatric patients. The aim of this study was to present our current surgical strategy with this disease, based on our pathologic findings and clinical experience. MATERIALS AND METHODS: This is a retrospective study of 29 patients treated, medically and surgically, at our centre. In 15 surgical patients, morphologic, morphometric and immunohistochemical studies for insulin, somatostatin and glucagon were performed and consequently it was possible to establish a focal and different forms of a diffuse type. RESULTS: Of 29 patients studied, 25 were diagnosed before one year of age and 4 between the first and second year of infancy. Of the first 25 patients, one died 7 hours post partum. Twelve patients received medical treatment alone: one died at 45 days of life and the remaining 11 had a good outcome. Another 12 patients additionally received surgical treatment. In 2 of these, adenoma were observed and removed and the patients cured. Subtotal pancreatectomy was performed in the remaining 10. (One case was normal and cured and the other 9 had the diffuse type.) Of these 9 patients with diffuse type, 4 died, 3 were cured and 2 underwent repeat surgery. Of the 4 patients diagnosed later, 3 underwent surgery (2 with adenomas and 1 diffuse type) and the other received medical treatment alone. CONCLUSIONS: We currently give medical treatment for all types and forms of PNHH. If the patient is resistant to therapy, adenoma is ruled out. If adenoma is diagnosed, it is removed. If the type is diffuse, near-total pancreatectomy is performed with a perioperative biopsy. In cases of hyperplasia or mixed forms we recommend total pancreatectomy and in cases of nesidioblastosis, partial pancreatectomy.

Adenoma, Islet Cell↗
PubMed2000

Identification of foetal brain proteins by two-dimensional gel electrophoresis and mass spectrometry comparison of samples from individuals with or without chromosome 21 trisomy.

Protein expression in foetal brain with or without chromosome 21 trisomy (Down's syndrome) was analyzed by two-dimensional gel electrophoresis and mass spectrometry. Data generated by in-gel digestion and matrix-assisted laser desorption/ionization mass spectrometry allowed identification of 40 proteins. Most of these are common to syndrome and healthy subjects and represent different types of protein. However, a few proteins, identified as truncated structural proteins (tubulin, actin), were present in part of the trisomy samples but absent from the controls. This is interpreted to indicate increased proteolysis in the syndrome samples but could also reflect some altered expression or processing. Independent of the apparently increased proteolysis in the syndrome samples, and in spite of the use of total brain tissues, the results show that two-dimensional protein separation patterns are largely similar between the syndrome and control samples upon silver-staining, but that differences associated with structural components can be detected and identified.

Brain↗
PubMed2000

Vascular endothelial growth factor is expressed in human fetal growth cartilage.

Angiogenesis is a crucial event in endochondral ossification. Chemoattractants and mitogens for endothelial cells (such as basic fibroblast growth factor [bFGF] and transforming growth factor beta [TGF-beta]), which act as local regulators of the process, are synthesized by chondrocytes under several stimuli and in relation to the differentiation stage of the cartilage. Vascular endothelial growth factor (VEGF) is a 44-kDa protein well known as a potent angiogenic molecule owing to its mitogenic and permeability-causing properties. In this work, VEGF was located by immunohistochemistry in growth plate cartilage of human fetuses (20-22 weeks old) and its expression was demonstrated by reverse-transcription polymerase chain reaction (RT-PCR). Primary culture of human fetal epiphyseal chondrocytes (HFEC) maintained VEGF expression at protein and messenger RNA (mRNA) levels and this expression was stimulated by cartilage-promoting growth factors incorporated into the culture media (rFGF-b, rTGF-beta1, and insulin-like growth factor [rFGF-b] at 50 ng/ml). The conditioned medium (CM) of HFEC stimulated the proliferation of endothelial cells, and this was partially blocked by anti-VEGF antibody. These studies showed VEGF production by chondrocytes of the epiphyseal growth cartilage and suggested a role of this factor in cartilage physiology and the angiogenic process.

Alternative Splicing↗
PubMed1998

Down's syndrome: altered chondrogenesis in fetal rib.

Down's syndrome (DS), a human genetic abnormality usually caused by an extra chromosome 21, presents a wide range of major and minor anomalies, the most significant of which are mental retardation and congenital heart defects. The anomalous phenotype also includes short stature and neck, thin calvaria, and cartilage hypoplasia. The genesis of these skeletal features is unknown. Histopathologic sections of fetal cartilage from skull, vertebra, rib, and femur were studied in 16 fetuses with DS (17-22 wk old) and 13 control non-DS fetuses (19-22 wk old) with other pathologies not directly affecting skeletal growth. Rib growth cartilage morphology showed a previously unreported structural anomaly in DS, an increase in the hypertrophic portion with a concomitant decrease in proliferative and resting zones. The hypertrophic chondrocytic zone was markedly increased in DS compared with non-DS (149 +/- 68 microm versus 36 +/- 20 microm, and 26 +/- 12 versus 7 +/- 3 expressed in percent of the total length; p < 0.0001), whereas the proliferative zone (114 +/- 58 microm versus 165 +/- 43 microm, 20 +/- 10 versus 33 +/- 4 in percent of the total length; p < 0.001) and the resting zone (53 +/- 4 versus 59 +/- 6 in %, p < 0.009) were decreased. These features were not found in the femoral epiphyseal growth plate or in cartilage from vertebra and skull. Our results demonstrate an imbalance toward the hypertrophic phenotype. This abnormality, found in DS fetuses 17-22 wk old, may represent an early manifestation of an abnormal growth cartilage maturation pattern, which manifests postnatally in long bones, leading to diminished growth rates.

Abortion, Therapeutic↗
PubMed1997

[The mixed gonadal dysgenesis. Diagnostic criteria and surgical treatment].

The Mixed Gonadal Dysgenesis represents the 7.6% of all our patients with intersexual states. We report 14 patients who present Mixed Gonadal Dysgenesis. We have studied: diagnosis age; external genitalia description; sex assigned in birth and if has changed; the karyotype; sex chromatine; hormonal study; genitography; internal genitalia and internal Mullerians ducts structures; gonadal histologycal study; surgical treatment and hormonal treatment. The results show that 50% of the cases presents a 46XY karyotype and the other 50% mosaicisme 45XO/46XY. The histological study is very distinctive. A vulvovagynoplasty and clitoroplasty was made in all the cases. Four patients must follow an hormonal treatment after reaching puberal age. Summing up, with patients having ambiguous genitalia we can suspect it consists of a Mixed Gonadal Dysgenesis. The diagnosis must be precocious. And this diagnosis will be based in an ambiguous genitalia, with a karyotype 46XY or 45XO/46XY, the persistence of the internal Müllerian duct structures, and the histological study with a dysgenetic testis. These patients should be raised as females because they can obtain a good morphological and functional development like a normal female.

Child, Preschool↗
PubMed1991

Preservation of the amputated canine hind limb by extracorporeal perfusion.

The hind limbs of six dogs were reimplanted immediately after amputation. Another nine were conserved by extracorporeal circulation for 24 h, and then examined histologically. A further six were conserved by the same method and then reimplanted after 24 h. Conservation by extracorporeal circulation maintained the limbs in good condition. Less than 5% of the muscle fibres showed abnormality when examined, and the lesions were reversible.

Amputation, Surgical↗
PubMed1989

Orbital metastasis, by transitional cell carcinoma of the bladder.

We report a new case of a patient with transitional cell carcinoma of the urinary bladder and a solitary metastasis to the orbita. A review of the literature shows two cases described previously. This case is interesting for the clinical features and evolution.

Carcinoma, Transitional Cell↗
PubMed1989

[Hypoplasia and pulmonary hypertension in Down syndrome: prognostic evaluation using pulmonary biopsy].

The pulmonary hypoplasia, in Down's syndrome with congenital cardiac malformation, probably explains the poor behaviour of these patients, leading to early vascular pulmonary lesions, which progress quickly. We present a case, in which the lung biopsy, done before cardiac surgery, showed a lung hypoplasia and also enabled us to establish the grading of the pulmonary vascular disease. The pathologic evaluation is necessary to decide upon the intracardiac repair and to predict the child's outcome.

Abnormalities, Multiple↗
PubMed1985

Brown adipose tissue changes in anencephalic infants. Image analysis study.

Perirenal brown adipose tissue was studied in 49 liveborn anencephalic infants of appropriate weight, whose lifespan ranged from 2 hours to 6 days. An additional series of 187 full-term infants was used as control. Morphological evidence of active and marked BAT lipolysis was found in large number of anencephalic infants suggesting that activation of BAT metabolism leading to lipolysis in the newborn does not depend on a diencephalic pathway but on peripheral mechanisms. Image analysis study did not sustain significant differences in the intrauterine storage of lipids in brown adipose tissue cells for the anencephalic and control infants who died within 24 hours of birth.

Adipose Tissue, Brown↗
PubMed1984

Hypothalamo-hypophyseal-testicular function in prepubertal boys with acute lymphoblastic leukemia following chemotherapy and testicular radiotherapy.

Hypothalamo-hypophyseal-testicular function was studied in twenty-eight prepubertal boys with ALL in clinical and haematological remission. Eighteen were treated with combined systemic chemotherapy (24-36 months) and the other ten, who had testicular leukemic infiltrates, received chemotherapy (38-60 months) and testicular radiotherapy (2 000 rad). Plasma levels of LH and FSH were measured before and after stimulation with LHRH (100 micrograms i.v.) and plasma levels of testosterone before and after stimulation with hCG (1 500 IU/48 h/7 doses). In patients treated with chemotherapy alone, mean basal LH and FSH, mean responses to LHRH stimulation and mean testosterone levels after stimulation with hCG did not significantly differ from those of the controls. Five of these patients who had normal testosterone values after three doses of hCG had testosterone values below the normal range after seven doses. In patients treated with chemotherapy and testicular radiotherapy, mean basal FSH and mean responses to LHRH stimulation were significantly higher than those of the controls. Testosterone values after stimulation with hCG were low in three and very low in the other seven. In both groups of patients data from testicular biopsies were consistent with functional results. We conclude that chemotherapy causes slight testicular damage, but chemotherapy and testicular radiotherapy produce severe testicular damage in patients with testicular leukemic infiltrates.

Child↗
PubMedDate not supplied

Anomalous costochondral cartilage in fetal anencephaly.

Anencephaly is a human fetal malformation with absence of brain and calvarium superior to the orbits. The consequent absence of hypothalamus provides a unique model for studying human development, and therefore skeletal growth, in the absence of hypothalamic hormones and their regulatory functions. To assess the influence of hypothalamic insufficiency on cartilage development, we studied costochondral cartilage sections from eight anencephalic fetuses (18-22 weeks old) and seven controls (16-22 weeks old) with pathologies not directly related to skeletal growth. We found a previously undescribed anomalous organization of the cartilage in the anencephalic. The proliferative chondrocytes showed a disordered appearance with an increased proliferative zonal length (156 +/- 28 microm in anencephalic fetuses vs. 103 +/- 14 microm in controls, p = 0.006) and a concomitant decrease in the maturing portion, where cells form ordered isogenic groups (58 +/- 13 microm in anencephalic fetuses vs. 93 +/- 19 microm in controls, p = 0.003). In addition, cell density was significantly decreased in the proliferating and maturing zones in the anencephalic cases (84 +/- 21 vs. 130 +/- 21 cells/40 microm(2) in proliferating zone; 53 +/- 8 vs. 94 +/- 8 in maturing portion, p < 0.005). These alterations in the developing cartilage of the anencephalic may contribute to the observed growth retardation in these fetuses and reflect modifications in pituitary hormones and growth factors resulting from reduction in hypothalamopituitary function.

Anencephaly↗
PubMedDate not supplied

Image analysis of neuroblastomas-discrimination of prognostic patterns.

In a series of 52 neuroblastomas with a three-year follow-up textural analysis by means of sequential transformation of the image enabled us to establish a prognostic stratification of the cases taking the value of the specific area at the tenth closure as a discriminant of the grade of differentiation. The curves obtained plotting the closing function mainly yield information on the size distribution and characteristics of the intercellular stroma, which largely corresponds to the neurofibrillar set. The correlation between the specific area at the tenth closure and the age of the children prompt us to consider two different trends in neuroblastomas, those which invariably lead to death and whose grade of differentiation bears no correlation with the outcome, and those which undergo spontaneous or treatment-induced regression, and whose maturity has a linear relationship with the age of the child at diagnosis.

Age Factors↗