Technique of management of subglottic stenosis

There have been innumerable approaches to the management of subglottic stenosis, which bear testimony to the difficulty in obtaining predictably satisfactory results. Management includes techniques of endoscopic dilation, laser resection, laryngofissure and stenting, and an ingenious array of plastic reconstructions with or without postoperative stenting. On occasion, permanent intubation with a conventional distal tracheotomy or a silicone rubber T tube may be used.     

Postintubation subglottic stenosis and cor pulmonale

In rats exposed to 400 revolutions (during 6 min and 40 sec) in rotating Noble-Collip drums essentially the same increase of the active form of hepatic glycogen phosphorylase as in animals studied 6 min and 40 sec after epinephrine (50 microgram/kg) or glucagon (100 microgram/kg), both i.v., was observed. However, in rats injured daily for 6 days, on day 7 this enzyme response was substantially blunted.     

Carbon dioxide laser serial microtrapdoor flap excision of subglottic stenosis

The recent development of microspot micromanipulators for the carbon dioxide laser with 250-microns spot sizes has greatly facilitated the extension of endolaryngeal procedures to children and neonates. It is possible to accurately develop microtrapdoor flaps within the limited exposures in the pediatric subglottis. We have used serial microtrapdoor flaps in the excision of subglottic scar tissue in eight children. In five children, the stenosis was improved with relief of stridor. In three children, the flaps were used as an adjunct to laryngotracheoplasty. The surgical techniques of this procedure are detailed in this report.     

The role of gentle ventilation in prevention of subglottic stenosis in the newborn

Although stuttering has long been acknowledged as a familial disorder, the nature of a genetic component remains unclear. Most previous data used in genetic studies were obtained primarily from adults who stutter and may be biased in several respects. The purpose of this investigation was to quantify the frequency of stuttering in relatives of preschool-age children who stutter, and who were first seen close to the onset of the disorder. Detailed pedigrees (family trees), including first-, second-, and third-degree relatives, were obtained from parents of 69 children who stuttered. We found, as have previous studies, that more male than female relatives ever stuttered, but that female subjects who stuttered had more female relatives who ever stuttered than did male subjects. In order to identify the genetic model most consistent with the observed patterns of stuttering transmission, we conducted segregation analyses. Results from these analyses suggest that transmission of a single major genetic locus increasing the liability to stuttering best accounts for the transmission of stuttering in families of preschool-age children who stutter.     

Growth factors in oncology

A patient with acquired pure red cell aplasia and agnogenic myeloid metaplasia (AMM) was treated with rHuEPO. She became transfusion independent. Weekly injections of rHuEPO have maintained the response without side-effects or disease progression. In addition, marrow fibrosis and splenomegaly have decreased. Therefore, rHuEPO may be effective therapy for some patients with acquired PRCA and/or AMM.     

Composite hyoid sternohyoid muscle grafts in humans. Its use in reconstruction of subglottic stenosis and the anterior tracheal wall

Successful results were achieved in three of four human cases of glottic, subglottic, and tracheal stenosis by using composite hyoid bone-muscle pedicle. A technique is used to create and interposition the grafts to widen the lumen and to provide structural support. The vital composite hyoid bone-muscle graft interposition technique offers a promising method for the solution of difficult cases of glottic, subglottic, and tracheal stenosis. Abandonment of previous long-term dilations is recommended in favor of early surgical restoration of a widened airway.     

Primary subglottic cancer

Ultraviolet (UV) light has been associated with the development of human non-melanoma skin cancers (NMSC). Such cancers often exhibit mutations in the p53 tumour suppressor gene. In order to determine the UV-induced p53 mutation spectrum, a yeast expression vector that harbours a human wild-type p53 cDNA was UV-irradiated in vitro and transfected into a yeast strain that contained the ADE2 gene regulated by a p53-responsive promoter. Forty-five mutant clones contained 51 mutations. Seven mutations were tandem base pair substitutions, four of which being CC-->TT, hallmark mutations of UV mutagenesis. Eighty percent (41/51) of the mutations were single or non-tandem base pair substitutions, the majority of which (27/41) were C-->T transitions. Ninety-five percent of such mutations occurred at dipyrimidine sites. Through a rigorous statistical test, the UV-induced p53 mutation spectrum appears to differ significantly (P < 0.008) from the one induced by the antineoplastic drug chloroethyl-cyclohexyl-nitrosourea, and to be indistinguishable from the one observed in NMSC (P = 0.4). These results demonstrate that the assay allows the determination of carcinogen-specific p53 mutation fingerprints and represents a new tool for molecular epidemiology.     

Growth factors in bladder cancer

This article is an overview of peptide growth factors, their receptors, and signal-transduction pathways that play a role in bladder cancer. Included in this overview are epidermal growth factor receptor and its ligands, erbB2, fibroblast growth factors, insulin-like growth factor, the transferrin receptor, and transforming growth factor-beta. The use of growth factors or growth factor receptors for diagnostic and therapeutic interventions is also discussed.     

Management of subglottic haemangioma

Two contrasting methods of treatment for paediatric subglottic haemangioma are presented. Dr Hoeve describes his results using intralesional steroids and short-term intubation, and Dr Froehlich discusses his outcomes with open surgical excision. Mr Bailey then reviews the currently available therapeutic options with special reference to each of the above techniques, and suggests an optimum plan of management given our current state of knowledge. The conclusion is that very small haemangiomas may not require treatment, or may be amenable to CO2 laser vaporization. Medium-sized lesions seem suitable for intra-lesional steroids and intubation, but large ones are probably best managed by primary submucous resection. Very large haemangiomas, and especially those which are circumferential or in which magnetic resonance imaging (MRI) shows extension down into the trachea and/or through the tracheal wall into the surrounding tissues, may be more safely dealt with by performing a tracheostomy and awaiting spontaneous involution.     

Increased subglottic gallium uptake in relapsing polychondritis

Gallium scintigraphy was performed on a 14-yr-old girl with subglottic airway narrowing that caused wheezing and dyspnea. The study showed increased gallium uptake in the neck. A biopsy was performed on the subglottic region, and the histology was compatible with relapsing polychondritis. After treatment with steroids, laboratory data that had indicated active inflammation soon normalized. Repeat gallium scintigraphy showed diminished uptake, although the subglottic stenosis did not improve. These results suggest that gallium scintigraphy is valuable for evaluating inflammatory activity in relapsing polychondritis.     

Growth factors and cytokines in uterine leiomyomas

Uterine leiomyomas, hard masses of smooth muscle-like tissue embedded in the myometrium, may be the most common tumors among humans. These tumors enlarge in as many as 30% of women over 30 years of age, cause significant morbidity, and are the most frequent indication for hysterectomy. Many researchers and clinicians have recently directed their attentions to understanding the etiology of these benign tumors, the conditions which cause their enlargement, and appropriate therapies which may be used as alternatives to hysterectomy. The ovarian steroid hormones estrogen and progesterone are known to play a central role in the pathology of leiomyomas. Both estrogen and progesterone contribute to the pathology of leiomyomas through gene regulation, but in opposing ways. During the follicular phase, estrogen maintains high expression of several genes which are normally expressed in the differentiated myometrium of pregnancy. During the luteal phase, progesterone can increase the mitotic activity of leiomyomas, particularly in younger women. Progesterone may act by inducing the production of growth factors and/or their respective receptors. This article surveys growth factors which may promote enlargement of susceptible leiomyomas. A potential role for cytokines in leiomyoma pathology is also discussed.     

Risk factors for restenosis after balloon angioplasty in focal iliac stenosis

BACKGROUND: The risk factors for restenosis after angioplasty have not yet been established because of the inconsistencies among treated lesions, differences in the techniques used, and variable end points. We evaluated the predictive variables relating to postangioplasty restenosis. METHODS: One hundred sixty-one transluminal balloon angioplasties were studied in 138 consecutive patients with focal iliac arterial stenosis (< or = 4 cm) caused by arteriosclerosis between January 1981 and December 1995. Restenosis was diagnosed on the basis of recurrent symptoms associated with an apparent drop in the ankle-brachial pressure index and angiographic visualization of restenosis. RESULTS: Being younger than 60 years (risk ratio 2.585) and poor runoff (risk ratio 2.328) were found to be important variables predicting restenosis by the Cox regression model. The restenosis-free patency rates were significantly better in patients older than 60 years of age (p = 0.0242), with good distal runoff (p = 0.0487), and without diabetes (p = 0.0111). CONCLUSIONS: Being younger than 60 years of age and poor distal runoff are important predictors of restenosis after iliac balloon angioplasty.     

Growth factors and the kidney in diabetes mellitus

Nephromegaly and mesangial matrix expansion observed in the diabetic kidney are all clues of a role of growth factors in the pathogenesis of these lesions. A growing body of evidence shows that changes in (1) insulin-like growth factor I regulation, and (2) the transforming growth factor beta loop exist in the kidney in the diabetic hypertrophic kidney and in diabetic glomerulosclerosis. However, other growth factors may be involved in some diabetic renal changes. The abnormalities in growth factor content and regulation, the role of growth factors in the diabetic kidney, and the effect of hyperglycemia and advanced glycosylation end products on growth factors in the kidney are reviewed.     

Growth factors and the gastrointestinal tract

This paper reviews areas of interest in gut mucosal growth factor physiology. Several epidermal growth factor (EGF)-like peptides (EGF, transforming growth factor [TGF]-alpha, heparin-binding EGF-like peptide, amphiregulin, and betacellulin) have been identified in the gut, EGF is produced by the salivary glands and is present in milk. It may act on the mucosa from the lumen as a surveillance peptide promoting mucosal repair. A stem-cell-derived "ulcer-associated cell lineage" develops adjacent to ulcers and produces EGF, which may play a role in ulcer healing. TGF-alpha is expressed by villus enterocytes and may have an important role in mucosal healing. The Trefoil peptides (pS2, spasmolytic polypeptide, intestinal trefoil factor) are protease resistant molecules secreted by mucin cells throughout the gut, with a role in mucosal healing. The TGF-beta family inhibit cell proliferation, and promote cell differentiation. TGF-beta has a gradient of expression along the crypt villus axis, with maximum production at the villus tip. It is suspected that it may prevent cell proliferation and support differentiation of villus enterocytes. Hepatocyte growth factor is a multifunctional growth factor expressed in many tissues, including the gastrointestinal tract. It has a role in organogenesis. Intestinal adaptation is highly dependent on enteral nutrition, and it is likely that growth factors are involved in adaptation. Little is known, however, about interactions between nutrients and growth factors. Milk contains a range of potentially important growth factors. Their biological significance is uncertain, and this is an area of active research.     

The open surgical approach to subglottic hemangioma

The monthly distribution of relapses in ulcerative colitis was analysed retrospectively to assess seasonal variation. In 338 patients who were regularly followed up at the colitis clinic, 1013 relapses occurred during the period 1977 to 1988. A peak of relapses occurred in the spring and autumn, with a decrease in the summer; the ratio of the observed to expected number of relapses was 201:255.3 for the summer, 289:252.6 for the autumn, 243:249.8 for the winter, and 280:255.3 for the spring. In contrast, month of diagnosis was evenly distributed without seasonality. The data support the concept that exacerbations in ulcerative colitis are influenced by seasonal factors.