Phonation and swallowing considerations in pediatric laryngotracheal reconstruction.

Experience with laryngotracheal reconstruction (LTR) has resulted in and continues to yield modifications and refinements in approach and technique with the goal to restore and maintain total laryngeal function. In addition to airway obstruction, the laryngeal functions of phonation and swallowing also may be affected by the underlying injury as well as by procedures designed to enlarge the airway. This paper discusses various problems encountered with phonation and swallowing in pediatric patients who underwent LTR and postoperative patients who were seen during the year July 1, 1990, through June 30, 1991.

[Phenylalanine hydroxylase-like antibody in human chorionic villi].

An antigen similar by electrophoretic mobility to liver phenylalanine hydroxylase (PH) and cross-reacting with monoclonal antibody PH8 against liver PH was detected in extracts of soluble proteins in 6 from 23 samples of chorionic villi. An antigen with electrophoretic mobility corresponding to 40-41 kDa was detected in extracts of membrane proteins from these 23 samples by immunoblotting with monoclonal antibody PH8. Its molecular weight was similar to that of major chymotryptic peptide of human liver PH.

Nasal mass in a pediatric patient.

The consultants agreed that the differential diagnosis should focus on congenital masses, including an encephalocele, glioma, dermoid, hamartoma, hemangioma, rhabdomyosarcoma, neurofibroma, and nasolacrimal duct cyst. There was some disagreement as to which is the best way to evaluate the mass, ranging from an MRI (Dr. Reilly), to CT scan (Dr.

CpG hotspot causes second mutation in codon 408 of the phenylalanine hydroxylase gene.

A new mutation has been identified in exon 12 of the gene encoding phenylalanine hydroxylase at codon 408. The single base change from guanine to adenine changes the amino acid arginine to glutamine; thus, the mutation is defined as R408Q. This codon is the site of a mutation known to causes phenylketonuria.

Physical abuse of children. A retrospective review and an otolaryngology perspective.

Child abuse is a common problem seen by practicing physicians. To further define the incidence and the type of head and neck injury in children referred for evaluation of child abuse, a 5-year retrospective study of 4340 patients was undertaken. Of these patients, 2950 (68%) were victims of sexual abuse, while 1390 (32%) were victims of physical abuse.

Phenylalanine positively modulates the cAMP-dependent phosphorylation and negatively modulates the vasopressin-induced and okadaic-acid-induced phosphorylation of phenylalanine 4-monooxygenase in intact rat hepatocytes.

The state of phosphorylation of phenylalanine hydroxylase was determined in isolated intact rat hepatocytes. 32P-labeled phenylalanine hydroxylase was immunoisolated from cells loaded with 32Pi or from cell extracts 'back-phosphorylated' with [gamma-32P]ATP by cAMP-dependent protein kinase. The rate of phenylalanine hydroxylase phosphorylation in cells with elevated cAMP was similar to that observed for the isolated enzyme phosphorylated by homogeneous cAMP-dependent protein kinase.

The coding sequence of the hemolytically inactive C4A6 allotype of human complement component C4 reveals that a single arginine to tryptophan substitution at beta-chain residue 458 is the likely cause of the defect.

The C4A6 allotype of the human complement component C4 is known to be defective in C5 binding within the C5 convertase. To characterize the position and nature of the molecular defect in the C4A6 allotype we have isolated the C4A6 gene from a cosmid genomic DNA library. Direct sequencing of a 4.

Construction of protein analogues by site-specific condensation of unprotected fragments.

The extreme sensitivity to periodate of 1-amino, 2-hydroxy compounds permits the selective conversion of N-terminal serine and threonine to an aldehydic group. We have used this reaction to construct analogues of human granulocyte colony stimulating factor (G-CSF) by allowing such oxidized peptides to react with others that have had a hydrazide derivative attached to the C-terminus by reversed proteolysis. Two recombinant analogues of G-CSF were used as starting materials.

Isolation of deoxyribonucleic acid (DNA) from saliva and forensic science samples containing saliva.

Saliva and saliva-stained materials were examined as potential sources of deoxyribonucleic acid (DNA) for DNA analysis and identity testing. In this paper, the authors demonstrate that DNA was isolated and DNA banding patterns suitable for DNA typing were obtained from fresh saliva and various saliva-stained materials, such as envelopes, buccal swabs, gags, and cigarettes. Furthermore, DNA and DNA banding patterns were obtained from actual forensic evidentiary samples containing mixed saliva/semen stains.

Innovations in pediatric laryngotracheal reconstruction.

Techniques for the reconstruction of pediatric subglottic and tracheal stenoses continue to undergo modification and refinement. The modified Réthi procedure of anterior laryngotracheal division and posterior cricoidotomy may be supplemented by unilateral or bilateral division of the cricoid cartilage for increased expansion of the subglottic lumen. The resulting four-quadrant division of the cricoid cartilage can be used in conjunction with the placement of cartilaginous grafts and stenting techniques common to laryngotracheal reconstruction (LTR).

Use of the chemical cleavage of mismatch method for prenatal diagnosis of alpha-1-antitrypsin deficiency.

The most common mutation in alpha-1-antitrypsin deficiency, conversion of a G to an A at base 9989 (PI-Z), was detected with the chemical cleavage of mismatch method, demonstrating the power of the method for prenatal diagnosis. Exon V of the gene was amplified using the polymerase chain reaction and heteroduplexes were formed to test for the presence of the mutation. The predicted C mismatch was readily detectable with hydroxylamine, and by making the probe from the chorionic villus sample it was possible to determine that the fetus was heterozygous, not homozygous, for the mutation.

Detection of mutations in DNA.

Methods for detecting known and unknown mutations are becoming increasingly important as new disease genes are identified and new mutations are found in them. These methods are also expensive and time consuming. Over the past year major efforts have been directed towards developing new assays and making current assays faster and cheaper.

Anastomosis of the cervical trachea in children.

Numerous techniques for the surgical management of laryngotracheal stenosis in children have been described in the literature. These surgical modalities include endoscopic management and open laryngotracheal reconstruction using costal cartilage grafts for expansion of the stenotic subglottic region. Although tracheal resection with primary reanastomosis for the management of tracheal stenosis is reported frequently in the adult population, children rarely have stenotic lesions that are amenable to this particular technique.

Diabetic glomerulosclerosis without diabetes mellitus--two case reports and a review of the literature.

The duration of diabetes mellitus and presence of hyperglycaemia appear to be important in the development of diabetic nephropathy. The presence of nodular glomerulosclerosis is thought to be pathognomonic of the condition. We report two patients with histological features of diabetic glomerulosclerosis who did not have diabetes mellitus.

Illegitimate transcription of phenylalanine hydroxylase for detection of mutations in patients with phenylketonuria.

Illegitimately transcribed phenylalanine hydroxylase mRNA was amplified using the polymerase chain reaction from both fibroblasts and Epstein-Barr virus-transformed lymphocytes. This method was used to study mutations of this gene in patients with phenylketonuria and known point mutations were easily detected. Illegitimate transcription was successful for studying splicing defects and it was found that the previously described mutation which changes G to A at the 5' donor site of intron 7 causes exon 7 to be spliced out.

Complete mutation detection using unlabeled chemical cleavage.

We have developed a strategy for the complete detection of point mutations, small insertions and deletions by chemical cleavage based on the methodology of Cotton et al. (1988). The technique was extended by the development of a nonisotopic cleavage product detection system using silver staining after gel electrophoresis.

Brain stem serotonin-synthesizing neurons in Alzheimer's disease: a clinicopathological correlation.

The location and number of brain stem serotonin-synthesizing neurons were analyzed in 11 patients with Alzheimer's disease (AD) and 5 age-matched controls using immunohistochemical techniques. In addition, the number of neuritic plaques and neurofibrillary tangles in the cortex and brain stem raphe was evaluated, as was the number of Nissl-stained raphe neurons. AD patients could be classified into two groups based on their raphe pathology; patients with such pathology (AD+) and those without (AD-).

A controlled trial of synthetic surfactant in infants weighing 1250 g or more with respiratory distress syndrome. The American Exosurf Neonatal Study Group I, and the Canadian Exosurf Neonatal Study Group.

Background: Surfactant-replacement therapy is now recognized as a life-saving and safe intervention in small premature infants, but there is little evidence concerning its risks and benefits in larger premature infants.

Methods: We conducted a placebo-controlled, blinded trial in 1237 infants with respiratory distress who were enrolled at 23 hospitals in the United States and 13 hospitals in Canada. At entry all the infants weighed at least 1250 g, were receiving mechanical ventilation, and had a ratio of arterial to alveolar oxygen tension below 0.

Functional endoscopic sinus surgery in the immunocompromised child.

Fungal sinusitis in the immunocompromised child is an aggressive, invasive process that may result in a fatal outcome if not diagnosed early. As a result of increasing use of bone marrow transplantation and new cytotoxic chemotherapeutic agents resulting in severe agranulocytopenia, more patients have become susceptible to fungal sinus disease. Functional endoscopic sinus surgery has emerged recently as an important surgical modality in the treatment of sinus disease in adults and children.

The problem of pediatric laryngotracheal stenosis: a clinical and experimental study on the efficacy of autogenous cartilaginous grafts placed between the vertically divided halves of the posterior lamina of the cricoid cartilage.

Acquired laryngotracheal stenosis is a well-documented complication of endotracheal intubation. Severe acquired laryngotracheal stenosis in children responds to surgical reconstruction, including the use of grafts and stents. The most commonly described graft material is autogenous cartilage, placed in the anterior laryngotracheal complex.

Atypical tracheobronchial vascular compression.

Vascular compression of the tracheobronchial tree frequently presents early in infancy with significant airway compromise. For this reason, the pediatric otolaryngologist is often consulted early in the assessment of these patients. Three unusual cases of tracheobronchial vascular compression are presented.