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1.
Pediatr Surg Int ; 37(1): 1-15, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33392698

ABSTRACT

Short bowel syndrome in neonates is a severe and life-threatening disease after a major loss of small bowel with or without large bowel. Intestinal adaptation, by which the organism tries to restore digestive and absorptive capacities, is entirely dependent on stimulation of the active enterocytes by enteral nutrition. This review summarizes recent knowledge about the pathophysiologic consequences after the loss of different intestinal parts and outlines the options for enteral nutrition and pharmacological therapies to support the adaptation process.


Subject(s)
Enteral Nutrition/methods , Gastrointestinal Agents/therapeutic use , Short Bowel Syndrome/therapy , Humans , Infant , Infant, Newborn , Intestine, Small/physiopathology , Short Bowel Syndrome/drug therapy , Short Bowel Syndrome/physiopathology
2.
J Biomed Mater Res B Appl Biomater ; 107(4): 1304-1309, 2019 05.
Article in English | MEDLINE | ID: mdl-30312527

ABSTRACT

Intestinal circumferential expansion is essential for bowel lengthening in patients with Short Bowel Syndrome. We hypothesized use of an endoluminal osmotic hydrogel expander (EOHE) as a novel approach for intestinal expansion. An EOHE was introduced into an isolated intestinal segment of New Zealand rabbits, with a similar segment created as a control. After 4weeks, the segments were retrieved for analysis. Weight, inflammatory markers and fluoroscopy data was recorded weekly. EOHE allowed successful expansion of intestinal segments from 4.68 ± 0.35 to 9.79 ± 0.35 cm (p = 0.01). Increase in intestinal length was 167.8 ± 35.21% in segments with EOHE vs. 23.03 ± 4.2% in the control group (p < 0.01). A significant intestinal dilatation (214.4 ± 1.58 vs. 34.59 ± 1.23%, p < 0.01) was demonstrated. Hematoxylin and eosin stain revealed conservation of intestinal architecture with muscle hypertrophy and flattening of the epithelium possibly due to compression. No reduction of rabbit weight, inflammatory markers or liver damage was described. EOHE appears to produce safe intestinal expansion, achieving increased length and dilatation suitable for lengthening procedure. This approach may allow development of similar techniques to expand bowel in short bowel patients. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1304-1309, 2019.


Subject(s)
Hydrogels , Jejunum , Short Bowel Syndrome , Tissue Expansion Devices , Animals , Female , Hydrogels/chemistry , Hydrogels/pharmacology , Jejunum/metabolism , Jejunum/pathology , Jejunum/surgery , Male , Polyesters/chemistry , Polyesters/pharmacology , Rabbits , Short Bowel Syndrome/metabolism , Short Bowel Syndrome/pathology , Short Bowel Syndrome/surgery
3.
Org Biomol Chem ; 13(21): 6066-72, 2015 Jun 07.
Article in English | MEDLINE | ID: mdl-25952831

ABSTRACT

Phage display antibodies are widely used to follow heparan sulfate (HS) expression in tissues and cells. We demonstrate by ELISA, that cations alter phage display antibody binding profiles to HS and this is mediated by changes in polysaccharide conformation, demonstrated by circular dichroism spectroscopy. Native HS structures, expressed on the cell surfaces of neuroblastoma and fibroblast cells, also exhibited altered antibody binding profiles following exposure to low mM concentrations of these cations. Phage display antibodies recognise conformationally-defined HS epitopes, rather than sequence alone, as has been assumed, and resemble proteins in being sensitive to changes in both charge distribution and conformation following binding of cations to HS polysaccharides.


Subject(s)
Antibodies/immunology , Epitopes/immunology , Heparitin Sulfate/immunology , Animals , Carbohydrate Conformation , Carbohydrate Sequence , Cations/immunology , Cell Line , Enzyme-Linked Immunosorbent Assay , Epitopes/chemistry , Heparitin Sulfate/chemistry , Humans , Mice , Peptide Library
4.
Cancer Res ; 74(21): 5999-6009, 2014 Nov 01.
Article in English | MEDLINE | ID: mdl-25164011

ABSTRACT

Heparan sulfate proteoglycans (HSPG) play a critical role in the interaction of tumor cells and their microenvironment. HSPG activity is dictated by sulfation patterns controlled by sulfotransferases, which add sulfate groups, and sulfatases (Sulf), which remove 6-O-sulfates. Here, we report altered expression of these enzymes in human neuroblastoma cells with higher levels of Sulf-2 expression, a specific feature of MYCN-amplified cells (MYCN-A cells) that represent a particularly aggressive subclass. Sulf-2 overexpression in neuroblastoma cells lacking MYCN amplification (MYCN-NA cells) increased their in vitro survival. Mechanistic investigations revealed evidence of a link between Sulf-2 expression and MYCN pathogenicity in vitro and in vivo. Analysis of Sulf-2 protein expression in 65 human neuroblastoma tumors demonstrated a higher level of Sulf-2 expression in MYCN-A tumors than in MYCN-NA tumors. In two different patient cohorts, we confirmed the association in expression patterns of Sulf-2 and MYCN and determined that Sulf-2 overexpression predicted poor outcomes in a nonindependent manner with MYCN. Our findings define Sulf-2 as a novel positive regulator of neuroblastoma pathogenicity that contributes to MYCN oncogenicity. Cancer Res; 74(21); 5999-6009. ©2014 AACR.


Subject(s)
Heparan Sulfate Proteoglycans/metabolism , Neuroblastoma/genetics , Nuclear Proteins/metabolism , Oncogene Proteins/metabolism , Sulfotransferases/biosynthesis , Cell Line, Tumor , Cell Survival , Gene Expression Regulation, Neoplastic , Humans , N-Myc Proto-Oncogene Protein , Neuroblastoma/pathology , Nuclear Proteins/genetics , Oncogene Proteins/genetics , Signal Transduction/genetics , Sulfatases , Sulfotransferases/genetics , Tumor Microenvironment/genetics
5.
J Pediatr Surg ; 46(5): e5-7, 2011 May.
Article in English | MEDLINE | ID: mdl-21616227

ABSTRACT

Life-threatening bleeding is a hazard of major tumor excision in children. However, fatalities from inadvertent arterial ligation should not be overlooked. Sacrococcygeal teratoma is the commonest neonatal tumor. Laparotomy to ligate the median sacral artery has been used to preempt potentially fatal resectional bleeding. Use of laparoscopy to achieve the same is an evolving technique, with only 7 neonatal cases described. As such, the Idea, Development, Exploration, Assessment, Long-term study (IDEAL) guidelines on surgical innovation recommend case reports addressing proof of concept, technical factors and safety tips. Fortunately, mistaken arterial division is so far unreported during laparoscopic median sacral artery ligation. However, as uptake widens, anatomical distortion by tumor and surgeon disorientation at endosurgery are risk factors for even such inconceivable complications. We report a successful case of laparoscopic vascular control for neonatal sacrococcygeal teratoma and demonstrate an observation that serves as a useful safety check for this procedure (as well as the open alternative).


Subject(s)
Hemostasis, Surgical/methods , Laparoscopy/methods , Spinal Neoplasms/surgery , Teratoma/surgery , Biomarkers, Tumor , Chorionic Gonadotropin/blood , Electrocoagulation , Hemostasis, Surgical/adverse effects , Humans , Infant, Newborn , Ischemia/prevention & control , Laparoscopy/adverse effects , Leg/blood supply , Ligation/methods , Postoperative Complications/prevention & control , Sacrococcygeal Region , Skin Ulcer/etiology , Spinal Neoplasms/blood , Spinal Neoplasms/blood supply , Teratoma/blood , Teratoma/blood supply , alpha-Fetoproteins/analysis
6.
J Pediatr Surg ; 46(3): e37-40, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21376186

ABSTRACT

Retroperitoneal teratomas are rare, often massive tumors usually presenting in infancy; being mostly mature lesions, their treatment is surgical but may represent a formidable challenge. Major vessel displacement may not be well demonstrated on imaging: vascular injuries are well-recognized surgical complications with urgent repair, ligation, or even segmental excision of major vessels being required. However, the literature provides few suggestions to avoid these problems. In our approach, we assessed the important effaced abdominal veins on imaging and at laparotomy to allow us to electively excise the suprarenal and infrarenal vena cava (with both renal vein ostia) and thereby resect a giant retroperitoneal teratoma without inadvertent vessel injury, major bleeding, renal disturbance, or tumor recurrence. Described for renal tumors, elective cavectomy has not been reported as a technique to manage primary retroperitoneal teratomas. In selected cases, with careful preservation of renal venous collaterals, we show this can be a well-tolerated, preemptive option to reduce the high risks of surgical complications.


Subject(s)
Elective Surgical Procedures/methods , Retroperitoneal Neoplasms/surgery , Teratoma/surgery , Vena Cava, Inferior/surgery , Female , Humans , Infant , Kidney/blood supply , Laparotomy , Ligation , Renal Veins/surgery , Retroperitoneal Neoplasms/diagnostic imaging , Teratoma/diagnostic imaging , Tomography, X-Ray Computed , Ultrasonography , Vena Cava, Inferior/pathology
7.
J Pediatr Surg ; 46(2): e15-7, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21292064

ABSTRACT

Abdominal lymphatic malformations may be challenging to eradicate. Retroperitoneal lesions may more difficult to resect than mesenteric ones; however, the latter may predispose to intestinal volvulus, leading to calls for their prompt excision. Such lesions identified perinatally may pose particular challenges: in one case, respiratory failure caused by abdominal distension required emergency drainage followed by later laparoscopic excision; laparoscopy has also been used promptly to diagnose and resect neonatal mesenteric lymphatic malformations with their inherent volvulus risk. We illustrate that even if neonatal laparoscopy identifies a retroperitoneal rather than mesenteric lymphatic malformation, curative endosurgical excision remains feasible.


Subject(s)
Laparoscopy/methods , Lymphatic Abnormalities/surgery , Cryptorchidism/surgery , Humans , Infant, Newborn , Lymphangioma, Cystic/surgery , Lymphatic Abnormalities/diagnosis , Male , Mesenteric Cyst/surgery , Retroperitoneal Space
8.
J Pediatr Surg ; 46(1): e13-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21238625

ABSTRACT

Hypercalcaemia is a rare life-threatening complication of paediatric cancer that is commoner in haematological than solid malignancies and associated rarely with acute renal failure. Often refractory to medical therapy, control of hypercalcaemia in children with solid tumours may necessitate excision of localised tumours or urgent chemotherapy for metastatic ones. We present a child with refractory hypercalcaemia, bulky chemosensitive metastatic tumours and acute renal failure in whom chemotherapy posed high-risk of tumour lysis syndrome (TLS). Resection of the metastatic tumours successfully normalised the hypercalcaemia and represents a practical alternative control strategy in cases at high risk of TLS.


Subject(s)
Dysgerminoma/surgery , Hypercalcemia/prevention & control , Tumor Lysis Syndrome/prevention & control , Acute Kidney Injury/epidemiology , Child , Dysgerminoma/epidemiology , Dysgerminoma/secondary , Female , Humans , Risk Factors , Tumor Lysis Syndrome/etiology
9.
J Pediatr Surg ; 45(10): e29-32, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20920706

ABSTRACT

High retropharyngeal neuroblastic tumors in children have been excised and debulked transorally or cervically, often with a covering tracheostomy. Although we and others have approached high thoracic lesions thoracoscopically, the trapdoor incision (or modification thereof) is generally reserved for cervicothoracic tumors with significant vessel encasement around the thoracic inlet. We report a case of symptomatic ganglioneuroma extending from the nasopharynx, at the level of the skull base, down to the aortic arch: macroscopic clearance was achieved via an extended trapdoor incision and without recourse to tracheostomy, transoral surgery, or transfusion.


Subject(s)
Aorta, Thoracic/surgery , Ganglioneuroblastoma/surgery , Neurosurgical Procedures/methods , Skull Base Neoplasms/surgery , Aorta, Thoracic/pathology , Child, Preschool , Female , Ganglioneuroblastoma/pathology , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/surgery , Humans , Magnetic Resonance Imaging , Skull Base/pathology , Skull Base/surgery , Skull Base Neoplasms/pathology , Thoracic Neoplasms/pathology , Thoracic Neoplasms/surgery , Treatment Outcome
10.
J Urol ; 178(4 Pt 2): 1650-3, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17707032

ABSTRACT

PURPOSE: Familial clustering of vesicoureteral reflux suggests that genetic factors have an important role in the pathogenesis of vesicoureteral reflux. Transforming growth factor-beta1 is a multifunctional peptide that controls proliferation and differentiation in many cell types. Recently an association between the transforming growth factor-beta1 -509 and +869 gene polymorphism, and renal parenchymal scarring was reported. We investigated the genetic contribution of transforming growth factor-beta1 in familial vesicoureteral reflux by examining the genotype frequencies of transforming growth factor-beta1 polymorphic variants. MATERIALS AND METHODS: The study included 141 families in which 1 or more siblings had primary vesicoureteral reflux. Renal parenchymal scarring was assessed using dimercapto-succinic acid scans. Genotyping was performed in 280 patients with vesicoureteral reflux, including 133 index patients and 147 siblings, and in 74 controls for the position -509 and the coding region at position 10 (+869) of the transforming growth factor-beta1 gene polymorphism by polymerase chain reaction, gel analysis and appropriate restriction digest. RESULTS: The genotype frequency of -509CC was significantly increased in the familial vesicoureteral reflux group compared to controls (58% vs 33%, p <0.01), whereas -509TT genotype frequency was significantly lower in the familial vesicoureteral reflux group compared to controls (7.5% vs 28%, p <0.01). Similarly there was a significant increase in the +869TT genotype (52% vs 32%, p <0.05), while the +869CC genotype was significantly lower in patients with familial vesicoureteral reflux compared to controls (11% vs 24%, p <0.01). There were no significant differences in transforming growth factor-beta1 genotype distribution between patients with vesicoureteral reflux with and without renal parenchymal scarring. CONCLUSIONS: To our knowledge this study demonstrates for the first time the association of the cytokine transforming growth factor-beta1 gene polymorphism in patients with familial vesicoureteral reflux. Individuals with the transforming growth factor-beta1 -509CC and 869TT genotype may have increased susceptibility to vesicoureteral reflux.


Subject(s)
Polymorphism, Genetic , Transforming Growth Factor beta/genetics , Vesico-Ureteral Reflux/genetics , Chi-Square Distribution , Child , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Polymerase Chain Reaction
11.
J Urol ; 174(4 Pt 2): 1609-11; discussion 1611, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16148664

ABSTRACT

PURPOSE: Reflux nephropathy (RN) is recognized as a major cause of end stage renal failure in children and young adults. Transforming growth factor-beta1 (TGF-beta1) is a potent proinflammatory and fibrogenetic cytokine known to have a key role in the regulation of renal tissue fibrosis. We investigate genotype frequencies for polymorphisms of the TGF-beta1 gene at position -509, codon 10 and 25, and examine circulating levels of TGF-beta1 in patients with reflux nephropathy. MATERIALS AND METHODS: Renal scaring was evaluated with 99technetium dimercapto-succinic acid renal scan. Genotyping was performed in 123 patients with severe to moderate reflux nephropathy and 58 controls for the position -509, the coding region at position 10 and 25 of the TGF-beta1 gene polymorphisms by polymerase chain reaction, gel analysis and appropriate restriction digest. TGF-beta1 serum levels were measured with standard ELISA technique. RESULTS: The genotype distribution of -509-CT was significantly increased in the RN group compared to controls, (82% vs 37%). Similarly, there was a significant increase in the CC Lue(10)-->Pro (codon 10) genotype (77% vs 27.5%, p <0.05), while TC Lue(10)-->Pro was significantly lower (7.3% vs 43%, p <0.05) in patients compared to controls. There was no significant difference in the Arg(25)-->Pro (codon 25) TGF-beta1 genotypes distribution between patients and controls. There were no statistically significant differences in the serum levels of TGF-beta1 in children with RN (4.2 +/- 0.3 mIU/ml) compared to controls (3.9 +/- 0.4 mIU/ml) (p >0.05). CONCLUSIONS: Patients with TGF-beta1 -509 and Lue(10)-->Pro gene polymorphisms may be at higher risk for reflux nephropathy.


Subject(s)
Polymorphism, Genetic/genetics , Transforming Growth Factor beta/genetics , Vesico-Ureteral Reflux/genetics , Adolescent , Case-Control Studies , Chi-Square Distribution , Child , Child, Preschool , Cicatrix/diagnostic imaging , Cicatrix/genetics , Enzyme-Linked Immunosorbent Assay , Genetic Predisposition to Disease , Genotype , Humans , Infant , Kidney Function Tests , Radioisotope Renography , Transforming Growth Factor beta1 , Vesico-Ureteral Reflux/diagnostic imaging
12.
Pediatr Surg Int ; 21(3): 143-7, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15756563

ABSTRACT

The high mortality in patients with congenital diaphragmatic hernia (CDH) has been attributed to pulmonary hypoplasia and persistent pulmonary hypertension (PPH). Endothelin-1 (ET-1), nitric oxide (NO), and calcitonin gene-related peptide (CGRP) have been reported to be important vasoactive mediators in the perinatal pulmonary circulation. The exact mechanism by which these vasoactive mediators interact to regulate the perinatal pulmonary vascular tone in CDH with PPH is not fully understood. We hypothesized that the altered pulmonary vascular reactivity in CDH is due to imbalance in vasoactive mediators. This study was designed to investigate mRNA expression of ET-1, eNOS, and CGRP in CDH lung in the perinatal period. A CDH model was induced in pregnant rats following administration of nitrofen. In control animals, the same dose of olive oil was given without nitrofen. Cesarean section was performed on day 21 of gestation. The newborn rats were intubated and ventilated, and ventilation was continued for 1-6 h. Left lungs were collected from both groups at 0, 1, and 6 h after ventilation (n=8 in each group). Reverse transcriptase-polymerase chain reaction on lung tissue was performed to evaluate the relative level of ET-1, eNOS, and CGRP mRNA expression. The results showed a significant increase in ET-1 mRNA in CDH lung at 1 and 6 h after ventilation compared with controls. In CDH lung, eNOS mRNA and CGRP mRNA levels were significantly increased at 1 h but were similar to control values at 6 h after ventilation. The increased expression of vasoconstrictor ET-1 mRNA and vasodilators eNOS mRNA and CGRP mRNA in the CDH lung at 1 h after ventilation suggests that pulmonary vascular tone is rapidly changing after birth. An imbalance in the production of vasoconstrictors and vasodilators by the CDH lung may contribute to high pulmonary vascular resistance.


Subject(s)
Calcitonin Gene-Related Peptide/genetics , Endothelin-1/genetics , Gene Expression Regulation, Developmental , Hernia, Diaphragmatic/metabolism , Nitric Oxide Synthase/genetics , Respiration, Artificial , Vascular Resistance/physiology , Animals , Animals, Newborn , Calcitonin Gene-Related Peptide/metabolism , Disease Models, Animal , Endothelin-1/metabolism , Female , Gene Expression Regulation, Developmental/physiology , Herbicides/toxicity , Hernia, Diaphragmatic/chemically induced , Hernia, Diaphragmatic/therapy , Lung/blood supply , Maternal Exposure/adverse effects , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type III , Phenyl Ethers/toxicity , Pregnancy , Prenatal Exposure Delayed Effects , Pulmonary Circulation/physiology , RNA, Messenger/genetics , Random Allocation , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Vasoconstriction/physiology , Vasodilation/physiology
13.
J Urol ; 172(4 Pt 2): 1604-6; discussion 1606, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15371770

ABSTRACT

PURPOSE: Interstitial scarring contributes to the progression of renal failure in reflux nephropathy. The proinflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) has been implicated in the disease susceptibility and pathogenesis of several inflammatory diseases promoting interstitial infiltration of inflammatory cells. We evaluate the frequency of TNF-alpha gene polymorphism in patients with reflux nephropathy. MATERIAL AND METHODS: Renal scarring was evaluated with technetium dimercapto-succinic acid renal scan. Genotyping was performed on 104 patients with reflux nephropathy and 30 controls for the TNF-alpha gene polymorphisms using polymerase chain reaction and restriction digest. This polymorphism involved a guanidine to adenosine transition at position -308 and was designated as TNF1 (-308G) and TNF2 (-308A). RESULTS: The allele frequencies of TNF1 and TNF2 were 18.8% and 81.2% in patients with reflux nephropathy and 76.7% and 23.3% in controls, respectively. The genotype distribution of TNF-alpha-AA was significantly higher (66.4% vs 10%, p <0.05), while the TNF-alpha-GG was lower (13.4% vs 60%, p <0.05) in patients with reflux nephropathy compared to controls. CONCLUSIONS: This study demonstrates for the first time the association of the cytokine TNF-alpha gene polymorphism in patients with reflux nephropathy. Our data suggest that patients with vesicoureteral reflux and TNF-alpha AA genotype may have increased susceptibility to reflux nephropathy.


Subject(s)
Polymorphism, Genetic , Tumor Necrosis Factor-alpha/genetics , Vesico-Ureteral Reflux/genetics , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male
14.
J Urol ; 172(4 Pt 2): 1607-9, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15371771

ABSTRACT

PURPOSE: Erythropoietin (EPO) is the principal factor regulating red blood cell production in humans. It has been shown that EPO gradually decreases with the progression of diabetic nephropathy and may be used as a marker of severity of disease. In vitro studies have shown that interleukin-10 (IL-10) acts synergistically with EPO to increase stimulation of erythroid differentiation and proliferation. We evaluate serum levels of EPO and IL-10 in children with reflux nephropathy (RN). MATERIALS AND METHODS: Serum level of EPO and IL-10 were measured in 32 girls and 22 boys with RN, and in 22 boys and 10 girls who served as healthy controls. Renal scarring was evaluated with Technetium dimercapto-succinic acid scan. RN was severe (less than 20% uptake) in 16 children, moderate (20% to 40% uptake) in 25 and mild RN (greater than 40% uptake) in 13. Because anemia may further stimulate EPO production we also compared the index Hb (hemoglobin) x EPO in all patients. IL-10 and EPO were measured with standard enzyme-linked immunosorbent assay technique. The unpaired t test was used for statistical analysis. RESULTS: There were no statistically significant differences in the serum levels of EPO in children with RN (6.11 +/- 0.51 mIU/ml) compared to controls (6.42 +/- 0.46 mIU/ml) (p >0.5). Similarly the index Hb x EPO was 75.25 +/- 5.65 in children with RN compared to 73.76 +/- 5.48 in controls. Mean EPO levels were similar for mild, moderate and severe RN. There was no difference in the serum levels of IL-10 in children with RN (23.14 +/- 2.32 pg/ml) compared to controls (22.67 +/- 4.13 pg/ml) (p >0.5). CONCLUSIONS: Although EPO has been reported to be a marker of progressive renal disease in diabetic nephropathy, our data indicate that serum levels of EPO do not reflect the severity of renal parenchymal damage in children with RN.


Subject(s)
Erythropoietin/blood , Kidney Diseases/blood , Vesico-Ureteral Reflux/blood , Child , Female , Humans , Kidney Diseases/etiology , Male , Severity of Illness Index , Vesico-Ureteral Reflux/complications
15.
BJU Int ; 94(3): 392-9, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15291875

ABSTRACT

OBJECTIVE: To investigate the role of nitric oxide (NO) in the pathogenesis of injury to the bladder mucosa after bladder outlet obstruction (BOO). MATERIALS AND METHODS: The response of bladder mucosa to BOO consists of thickening with fibrous connective tissue; NO is a multipurpose messenger important in blood vessel relaxation, neuronal communication and inflammatory activities of macrophages, and is synthesized by NO synthase (NOS), with three distinct isoforms; inducible (iNOS), endothelial (eNOS) and neuronal (nNOS). Fifteen male guinea pigs had a silk ligature placed around the bladder neck to induce BOO; controls included five sham-operated animals. The animals were killed at 2, 4, 6, 8 and 12 weeks after BOO. NADPH-diaphorase staining was used as a nonspecific method to determine NOS isoform distribution. Single- and double-label immunofluorescence histochemistry for iNOS, eNOS, nNOS and macrophage colony stimulating factor (M-CSF) were used, with laser scanning confocal microscopy to assess the results. The relative amount of iNOS mRNA was evaluated using reverse-transcription-polymerase chain reaction (RT-PCR), and a standard method to determine the degree of apoptosis. RESULTS: Bladder mucosa had a markedly increased intensity of NADPH-diaphorase staining 2 weeks after BOO. iNOS immunoreactivity was markedly greater in the bladder mucosa 2 weeks after BOO than in controls. The immunolocalization of iNOS and M-CSF was identical in bladder mucosa after BOO. RT-PCR showed stronger iNOS mRNA expression in the obstructed bladder mucosa 2 weeks after BOO than in controls. eNOS and nNOS expression was detected only 8 weeks after BOO, with markedly more immunoreactivity 12 weeks after initiating BOO. Increased eNOS and nNOS immunoreactivity strongly correlated with the induction of apoptosis in the bladder mucosa. CONCLUSION: There was overexpression of iNOS by activated macrophages in the early stages of BOO. This overexpression did not induce apoptosis in the iNOS-expressing cells of bladder mucosa in the early stages. After long-term BOO bladder mucosa showed strong eNOS and nNOS immunoreactivity, correlating with apoptosis. Thus we suggest that eNOS and nNOS, by triggering cell death, may be important in eliminating hyperplastic urothelial cells, reflecting the plasticity of the bladder response to obstructive stimuli.


Subject(s)
Nitric Oxide/physiology , Urinary Bladder Neck Obstruction/etiology , Urinary Bladder/enzymology , Animals , Apoptosis , Guinea Pigs , Immunohistochemistry/methods , Male , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Reverse Transcriptase Polymerase Chain Reaction/methods , Urinary Bladder Neck Obstruction/enzymology , Urothelium/metabolism
16.
BJU Int ; 94(1): 143-6, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15217450

ABSTRACT

OBJECTIVE: To investigate the distribution of c-kit-positive interstitial cells of Cajal (ICCs) in normal bladder and bladders from patients with megacystis-microcolon-intestinal peristalsis syndrome (MMIHS, a rare congenital and generally fatal cause of functional intestinal obstruction in the newborn), the most characteristic feature of which is abdominal distension caused by a distended unobstructed urinary bladder. PATIENTS AND METHODS: Full-thickness bladder specimens were obtained from four infants with MMIHS and four controls, and processed as paraffin-wax and frozen sections. Sections were assessed using single immunohistochemistry with monoclonal and polyclonal anti-c-kit antibodies. Anti-alpha-smooth muscle actin (SMA) antibody was used to investigate the contractile apparatus in smooth muscle cells of the urinary bladder. Specimens were examined using light and confocal scanning microscopy. RESULTS: There were many c-kit positive ICCs in the normal urinary bladder, appearing as small, long, bipolar cells with only two long and several short processes. In contrast, ICCs were absent in the MMIHS bladder. alpha-SMA immunoreactivity was lower in MMIHS urinary bladder than in control sections. CONCLUSION: This study shows for the first time the presence of c-kit-positive ICCs in the normal human urinary bladder. The lack of ICCs in the MMIHS bladder may contribute to the voiding dysfunction in this disease.


Subject(s)
Colon/abnormalities , Colonic Diseases/pathology , Intestinal Obstruction/pathology , Peristalsis , Proto-Oncogene Proteins c-kit/metabolism , Urinary Bladder/abnormalities , Colon/metabolism , Colonic Diseases/congenital , Connective Tissue Cells/metabolism , Dilatation, Pathologic/congenital , Dilatation, Pathologic/metabolism , Humans , Immunohistochemistry , Infant , Intestinal Obstruction/congenital , Mast Cells/metabolism , Muscle, Smooth/metabolism , Syndrome , Urinary Bladder/metabolism , Urinary Retention/congenital , Urinary Retention/pathology
17.
Pediatr Surg Int ; 20(4): 243-7, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15064961

ABSTRACT

Renal dysplasia (RD) is a disorganised development of renal parenchyma that results in a deficit of functional renal tissue. It is known that the epidermal growth factor (EGF) and the transforming growth factor-alpha (TGF-alpha) enhance renal cell proliferation, migration and differentiation during kidney development through binding to the same EGF receptor (EGFR). The aim of the study was to analyse the expression of TGF-alpha and EGFR in the dysplastic kidney. The specimens of dysplastic upper poles duplex kidneys were surgically resected from 19 patients. Indirect immunohistochemistry was performed using the ABC method employing antibodies against EGFR and TGF-alpha, and gene expression using primers specific to the human genes. There was absent or weak EGFR and TGF-alpha immunoreactivity in normal kidney tissue. In dysplastic kidneys, there was strong TGF-alpha and EGFR immunoreactivity in the epithelium of primitive tubules and strong EGFR immunoreactivity in the connective tissue around the primitive tubules. Our findings of markedly increased local expression of EGFR and TGF-alpha in primitive tubules suggest that EGFR and TGF-alpha may play an important role in altering renal morphogenesis resulting in renal dysplasia.


Subject(s)
ErbB Receptors/biosynthesis , Kidney/metabolism , Transforming Growth Factor alpha/biosynthesis , Urogenital Abnormalities/metabolism , Child , Child, Preschool , ErbB Receptors/metabolism , Female , Humans , Infant , Kidney/abnormalities , Male , Transforming Growth Factor alpha/metabolism
18.
Pediatr Surg Int ; 20(3): 192-6, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15088113

ABSTRACT

The newborn with congenital diaphragmatic hernia (CDH) is at high risk of developing persistent pulmonary hypertension (PPH). Recently, smooth muscle K(+) channels have been implicated in hypoxic pulmonary vasoconstriction in adults. We hypothesized that the hyperreactivity of the newborn pulmonary vasculature in CDH might reflect a relatively low level of smooth muscle K(+) channel activity because of hypoxemia, which could give rise to excessive smooth muscle cell depolarisation and lead to failure of the pulmonary vasculature to adapt to extrauterine life. We therefore investigated K(+) channel subunits in pulmonary artery smooth muscle cells (PASMC) in the nitrofen-induced CDH lung in rats. The CDH model was induced in pregnant rats after administration of 100 mg nitrofen on day 9.5 of gestation (term = 22 days). Dexamethasone (0.25 mg/kg) was given on days 18.5 and 19.5 of gestation. Cesarean section was performed on day 21. Fetuses were divided into three groups: group I, normal control; group II, nitrofen-induced CDH; and group III, nitrofen-induced CDH with antenatal dexamethasone treatment. Reverse transcription polymerase chain reaction (RT-PCR) was performed to evaluate the relative amount of the potassium channels Kv1.2, Kv2.1, and KvCa mRNA. Indirect immunohistochemistry was performed using a laser scanning confocal microscope with anti-Kv1.2, -Kv2.1, and -KvCa antibodies. In the CDH lung, Kv1.2, Kv2.1, and KvCa immunoreactivity was markedly decreased in PASMC compared with controls. Relative mRNA levels of potassium channel anti-Kv1.2, -Kv2.1, and -KvCa were significantly decreased in the CDH lung compared with controls (p<0.05). Dexamethasone treatment increased Kv1.2, Kv2.1, and KvCa immunoreactivity and mRNA levels in the CDH lung. Changes in voltage-gate K(+) channel subunits expression in the CDH lung suggest that potassium channels may play an important role in the development of pulmonary hypertension. Antenatal dexamethasone may modulate pulmonary vascular tone in the CDH hypoplastic lung by selectively upregulating local expression of Kv1.2, Kv2.1, and KvCa.


Subject(s)
Hernias, Diaphragmatic, Congenital , Muscle, Smooth, Vascular/metabolism , Persistent Fetal Circulation Syndrome/physiopathology , Potassium Channels/metabolism , Pulmonary Artery/metabolism , Analysis of Variance , Animals , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Dexamethasone/pharmacology , Dexamethasone/therapeutic use , Disease Susceptibility , Hernia, Diaphragmatic/complications , Humans , Infant, Newborn , Persistent Fetal Circulation Syndrome/complications , Persistent Fetal Circulation Syndrome/drug therapy , Potassium Channels/drug effects , Potassium Channels/genetics , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Up-Regulation
19.
J Pediatr Surg ; 39(3): 302-6; discussion 302-6, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15017542

ABSTRACT

BACKGROUND/PURPOSE: The renin-angiotensin system plays an important role in pulmonary artery remodelling. Several polymorphisms of genes encoding for components of the renin angiotensin system such as the angiotensin converting enzyme (ACE), the angiotensinogen (AGT) gene, and the angiotensin II type 1 receptor (ATIR) have been associated with the development of pulmonary hypertension. The aim of this study was to investigate the ACE I/D genotype, the M235 T polymorphism of the AGT gene and the A1166 C polymorphism of AT1R in the lungs of congenital diaphragmatic hernia (CDH) complicated by persistent pulmonary hypertension (PPH) in the newborn. METHODS: Genomic DNA was extracted from archival paraffin-embedded lung tissue from 13 newborns with CDH complicated by PPH and from 9 controls. Genotyping for the I/D-ACE, the M235 T-AGT, and the A1166 C-ATIR gene polymorphisms were determined by a polymerase chain reaction-based method with appropriate restriction digest when required. RESULTS: In controls, ACE genotype distribution of DD, ID, and II was 11%, 33%, and 55%, respectively, whereas in CDH it was 70%, 15%, and 15%, respectively. The ACE-DD genotype was significantly higher in CDH compared with controls (P <.05). In CDH samples, the prevalence of AGT-MM genotype was lower (8% v. 33%; P <.05), whereas the AGT-TT genotype was higher (61% v. 22%; P <.05) compared with controls. There were no differences in allele frequencies of AT1R between CDH patients and controls. CONCLUSIONS: These data suggest that D allele of the ACE gene insertion/deletion polymorphism and angiotensinogen M235 T polymorphism may be associated with PPH in newborns with congenital diaphragmatic hernia.


Subject(s)
Hernia, Diaphragmatic/genetics , Hernias, Diaphragmatic, Congenital , Hypertension, Pulmonary/congenital , Hypertension, Pulmonary/genetics , Renin-Angiotensin System/genetics , Alleles , Angiotensin II , Angiotensinogen/genetics , Case-Control Studies , Gene Frequency , Hernia, Diaphragmatic/complications , Humans , Hypertension, Pulmonary/complications , Infant, Newborn , Peptidyl-Dipeptidase A/genetics , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Receptors, Angiotensin/genetics
20.
Pediatr Surg Int ; 19(12): 755-9, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14714133

ABSTRACT

Newborn infants with congenital diaphragmatic hernia (CDH) still have a high mortality rate. Epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) are peptide growth factors involved in the fetal lung growth and development. The EGF and TGF-alpha have been reported to promote pulmonary branching activity and alveolar type-II pneumocyte proliferation. Epidermal growth factor and TGF-alpha immunoreactivity and mRNA expression in the bronchial and bronchiolar epithelium is maximal during early fetal life and barely detectable in the proximal airways of neonatal lung. The purpose of this study was to determine protein and gene expression of EGF and TGF-alpha in CDH lung in order to elucidate the potential role of these growth factors in the pathogenesis of pulmonary hypoplasia in CDH. Lung tissue specimens were obtained from archival lung tissue from 11 patients with CDH and 5 controls. Indirect immunohistochemistry was performed using ABC method with anti-EGF and anti-TGF-alpha antibodies. In situ hybridization was performed using EGF and TGF-alpha specific digoxigenin-labeled oligonucleotide probes. The most striking difference between hypoplastic CDH lung and control lung was the strong EGF and TGF-alpha mRNA expression and immunoreactivity in the bronchial and bronchiolar epithelium in CDH lung. The upregulated protein and gene expression of EGF and TGF-alpha in the proximal airways in the CDH hypoplastic lung suggests persistence of fetal stage of pulmonary airway development in CDH.


Subject(s)
Epidermal Growth Factor/biosynthesis , Hernia, Diaphragmatic/complications , Lung Diseases/metabolism , Respiratory Mucosa/pathology , Transforming Growth Factor alpha/biosynthesis , Epidermal Growth Factor/genetics , Gene Expression , Humans , Infant, Newborn , Lung Diseases/congenital , Lung Diseases/genetics , Lung Diseases/pathology , Transforming Growth Factor alpha/genetics , Up-Regulation
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