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Michael J Nowicki

Publications and source records attributed to Michael J Nowicki.

11 recordsLinked to original sources
PubMed2005

Colonic chicken-skin mucosa in children with polyps is not a preneoplastic lesion.

Colonic polyps are common both in adults and children; however, the malignant potential varies according to the type of polyp. Most childhood polyps are solitary juvenile polyps, which have negligible malignant potential. Chicken-skin mucosa (CSM) is an endoscopic finding initially described associated with adenomatous polyps and adenocarcinoma, suggesting a preneoplastic lesion. Subsequently, CSM was described in association with juvenile polyps, suggesting that this mucosal finding is not a precursor to dysplasia. To determine whether CSM represents a preneoplastic lesion, we studied endoscopic colonic mucosal biopsies for markers of cell replication (Ki-67) and malignant transformation (p53) in mucosal biopsies of CSM, normal colonic tissue, tubular adenomas, and adenocarcinomas. Samples were subjected to immunostaining for the presence of Ki-67 and p53. The degree of Ki-67-positive staining cells was similar for CSM and normal colonic tissue, whereas there was significantly increased staining for both tubular adenomas and adenocarcinomas. There was no evidence of p53 staining in CSM and normal colonic mucosa, whereas there was varying degrees of staining in tubular adenomas and adenocarcinomas. The association of CSM with benign juvenile polyps and the absence of histologic markers for increased replication and malignant transformation support the notion that this endoscopic finding is not preneoplastic. Rather, CSM arises in proximity to polyps of all histologic types because of local mucosal damage.

Adenocarcinoma↗
PubMed2005

The role of UGT1A1*28 mutation in jaundiced infants with hypertrophic pyloric stenosis.

Hypertrophic pyloric stenosis (HPS) may be accompanied by jaundice, a condition referred to as the icteropyloric syndrome (IPS). It has long been suspected that the etiology of IPS is an early manifestation of Gilbert's syndrome (GS). Clinical features common to both GS and IPS include jaundice precipitated by fasting and improved with feeding. Prevalence of jaundice in HPS is similar to that of clinically apparent GS in the general population. Discovery of a mutation in the promoter region of the bilirubin uridine diphosphate glucuronosyl transferase gene (UGT1A1*28) as the most common cause of GS has provided a tool to determine the role of GS in IPS. The aims of this study were to determine 1) the prevalence of IPS in a large group of infants with HPS, 2) whether disease severity contributed to the manifestation of IPS, and 3) whether GS played a role in IPS. Radioactive PCR and sequencing were used to determine the presence of UGT1A1*28 mutations. We determined a prevalence of IPS of 14.3% in HPS. Infants with IPS had significantly higher levels of alkalosis than infants with HPS alone. GS mutations were 4-fold higher in IPS (43.8%) than HPS (10.7%). In conclusion, the frequency of jaundice in HPS is similar to that of clinically apparent GS in the general population. Manifestation of IPS results from a more severe degree of metabolic disturbance and the presence of GS mutations.

Base Sequence↗
PubMed2003

Developmental expression of endothelial nitric oxide synthase (eNOS) in the rat liver.

Transition from fetal to postnatal life requires significant changes in cardiac, pulmonary, and hepatic blood flow. As such, there must be changes in vascular control in these vascular systems. Vascular resistance, a major contributor to blood flow, is mediated in the ductus arteriosus and pulmonary vasculature by endothelial nitric oxide synthase (eNOS). This study was conducted to determine the ontogeny of hepatic eNOS expression and activity. Additionally, the expression and activity of inducible nitric oxide synthase (iNOS) was measured to determine whether perinatal hypoxia resulted in detectable levels. NOS mRNA and proteins were determined by reverse transcription PCR assay and semiquantitative Western blot analysis, respectively. NOS activity was measured by the formation of [14C]-citrulline from [14C]-arginine. Localization of eNOS within the liver was determined by immunohistochemistry. eNOS mRNA was detectable at low levels at 18-d gestation and increased after birth, reaching a maximum level (4.5-fold increase) at 20 d of life. Parallel patterns for eNOS protein and activity were seen, with 6.9-fold and 16.1-fold increases, respectively. In the prenatal rat, eNOS was localized to areas of extramedullary hematopoiesis, with little signal in the sinusoids. Postnatally, there was a decrease in staining in the hematopoietic cells and a gradual increase in the staining of the endothelium of the sinusoids and central veins. iNOS mRNA and protein could not be detected at any age. eNOS expression and activity are developmentally regulated, increasing after birth coincident with an initial relative hypoxia and an increase in shear forces upon closure of the ductus venosus.

Animals↗
PubMed2003

The helpful colon.

Explore the source record for details and available documents.

Colonic Diseases↗
PubMed2002

Unsedated upper endoscopy in children.

BACKGROUND: EGD is essential to the investigation and treatment of GI disorders in children. Although safe, EGD has the potential for complications, in particular cardiopulmonary abnormalities associated with intravenous sedation. EGD is often performed in adults without sedation. Unsedated EGD is occasionally performed in children but has not been subjected to study. This study assessed the safety, efficacy, and feasibility of unsedated EGD in children. METHODS: Selected, highly motivated children requiring EGD were offered the choice of sedation or no sedation for the procedure. Children recorded scores for pain (face scale) and anxiety (vertical visual analogue scale) before and after EGD. In addition, the times required to prepare the patient, perform the EGD, and recover the patient were recorded. RESULTS: There was no difference in age, gender, or pre-EGD pain scores between children selecting sedation or no sedation. However, children selecting sedation had significantly higher pre-EGD anxiety scores than those who chose no sedation. Successful completion of EGD was similar for sedated (96.3%) and unsedated (95.2%) children. Post-EGD scores for anxiety were significantly decreased in those receiving sedation and unchanged in children who received no sedation. There was no significant change in post-EGD pain score in either group. Nearly 80% of children undergoing unsedated EGD would elect to forego sedation if EGD was needed again. Total procedure time was significantly longer in sedated versus unsedated children, reflecting longer preparation and recovery. CONCLUSIONS: Unsedated EGD can be performed safely and successfully in children with good patient tolerance. There was a significant decrease in total procedure time for children who have unsedated EGD. Unsedated EGD should be considered a viable option for motivated children.

Adolescent↗
PubMed2002

The inflammatory polyp-fold complex in children.

The inflammatory polyp-fold complex (IPFC) is an uncommon endoscopic or radiologic finding in children. In this complex, an inflammatory polyp at the gastroesophageal junction is present, often in continuity with a prominent gastric fold. Histologically, there is an inflammatory infiltrate in otherwise benign gastric and esophageal mucosa. We report four cases of IPFC in children, all associated with reflux esophagitis. In two patients who underwent repeat endoscopy, acid suppression therapy led to a decrease in the size of the polyp and histologic improvement of esophagitis. Four case studies in children with IPFC are presented, followed by a literature review of this endoscopic finding as it applies to children.

Adolescent↗