Identification of platelet receptors for bovine von Willebrand factor on human platelets by a new platelet receptor test.

A new test for the quantitation of platelet receptor activity for bovine von Willebrand factor in human platelet extracts is described. The test is based on the competition for the von Willebrand factor occurring between platelets, an antibody against von Willebrand factor, and platelet extracts containing the von Willebrand receptor. Bovine von Willebrand factor aggregates human platelets directly. In the presence of EDTA, anti-bovine von Willebrand factor antibody disaggregates platelet aggregates induced by bovine von Willebrand factor. Disaggregation is measured by following the decrease in light transmission accompanying disaggregation. Platelet extracts inhibited the disaggregating activity of the antibody, and the percent inhibition was directly proportional to the amount of the platelet extract added. The decrease in platelet disaggregating activity of the antibody was used as an indicator of platelet receptor activity in a system consisting of platelet-rich plasma, bovine von Willebrand factor, antibody and platelet extract. With this method we found von Willebrand factor receptors in the whole platelet extract, the Triton X-100 platelet membrane extract and in platelet extract material which bound to a bovine Willebrand factor-Sepharose 6MB affinity column.

The action of immobilized thrombin on factor VIII, fibrinogen and a synthetic tripeptide.

Bovine thrombin was insolubilized by attachment to cyanogen bromide-activated Sepharose (Sepharose-thrombin) or to activated (Affi-Gel 10) agarose containing a 10 A long arm (Affi-Gel-thrombin). Coupling in both instances approximated 7,000 units of thrombin per ml packed gel as determined by 125I-thrombin incorporation. The thrombin beads hydrolyzed the synthetic tripeptide Bz-Phe-Val-Arg-pNA (S-2160) at different rates, with the Sepharose-thrombin more active (220 esterase units per ml) than Affi-Gel thrombin (20.4 units per ml). The Km was significantly higher for the insolubilized thrombins (2 X 10(-3) M) than uncoupled thrombin (Km = 8 X 10(-5) M). The Sepharose-thrombin activated factor VIII significantly more rapidly than Affi-Gel-thrombin. Neither matrix-bound thrombin clotted a fibrinogen solution or liberated significant amounts of fibrinopeptides over 48 hr. This data indicates that a proteolysis of factor VIII, rather than a complex with thrombin, is the method of activation of factor VIII and that factor VIII is more accessible to the action of immobilized thrombin than is fibrinogen.

Small cell carcinoma of the head and neck.

Treatment methods for patients with small cell carcinoma of the head and neck are changing. Increasing clinical experience with these tumors and a better appreciation of patterns of recurrence, the need for thorough tumor staging, and the importance of chemotherapy as a form of primary therapy have contributed to these changes. Current concepts regarding small cell carcinoma arising in the head and neck are reviewed. Reported results of treatment for a variety of head and neck sites and site-specific relapse rates are summarized. New cases of small cell carcinoma arising in the hypopharynx, paranasal sinus, and from an unknown primary are added to the reported experience in the literature.

Preoperative assessment of tracheoesophageal speech.

Air insufflation testing of tracheoesophageal (TE) puncture candidates as currently practiced lacks objectivity and relies on subjective evaluation of the sound produced. Intraesophageal pressure measurements were obtained from 21 consecutive laryngectomized patients during air insufflation by either experienced examiners or a compressed air source at 1 liter or 3 liters per minute. Postoperatively, three levels of TE speech fluency were identified. Preoperative intraesophageal pressure measurements were associated with a specific post-TE puncture speech fluency result. Intraesophageal pressure measurements may offer a reliable objective preoperative assessment of post-TE puncture speech fluency and identify patients who would benefit from pharyngeal myotomy at the time of TE puncture.

Surgical treatment of pharyngoesophageal spasm.

The clinical course of 17 laryngectomees with pharyngoesophageal spasm who underwent pharyngeal myotomy was studied to determine clinical response and complications. The influence of speech therapy on the development of volitional control of pharyngoesophageal spasm, tracheoesophageal speech fluency, and the efficacy and complications of surgical treatment for pharyngoesophageal spasm were assessed. Volitional control of tracheoesophageal speech was never achieved. Ninety-four percent of the patients (16/17) were successfully rehabilitated following surgical therapy. The complications following pharyngeal myotomy were acceptable.

Small cell carcinoma of the larynx: results of therapy.

Primary small cell carcinoma of the larynx is a rare malignancy with a dismal prognosis. A survey of the long-term follow-up from reported cases of small cell carcinoma of the larynx and a review of the recent experience with this tumor at the University of Michigan Hospitals was undertaken to determine if newer treatment approaches incorporating adjuvant chemotherapy were associated with prolonged survival. Median survival for those patients receiving adjuvant chemotherapy was 19 months compared to 11 months for patients treated with surgery and/or radiation therapy alone. Among patients treated initially with primary radiation therapy and adjuvant chemotherapy median survival was 55 months, which was significantly longer than any other treatment regimen (P = 0.02). Systemic chemotherapy and therapeutic irradiation appears to offer the least disabling and most efficacious form of current therapy.

Aldred Scott Warthin. The man behind the tumor.

The personal milestones of Aldred Scott Warthin are detailed. One of the pathologic specimens that served as the basis for his original description of papillary cystadenoma lymphomatosum is reviewed.

Otolaryngologic features of Laurence-Moon-Bardet-Biedl syndrome.

The most common otolaryngologic features associated with LMBBS include SNHL, speech and language disorders, and oral and dental abnormalities. Early otolaryngologic, audiologic, speech pathology, and dental evaluation of these individuals is recommended. This is the first reported case of bifid epiglottis, a rare congenital laryngeal anomaly, found in association with LMBBS. Most patients with bifid epiglottis have additional congenital anomalies, most commonly polysyndactyly. Polysyndactyly is a feature of both LMBBS and bifid epiglottis and may be an early hallmark for the presence of other congenital anomalies.

Carcinoid (neuroendocrine carcinoma) of the larynx.

Carcinoid of the larynx is a rare aggressive malignancy with few long-term survivors. Three cases of laryngeal carcinoid treated at the University of Michigan and 23 cases reported previously are reviewed. The clinical behavior, patterns of metastasis, and response to therapy were analyzed to determine optimal therapeutic evaluation and treatment strategies. Patient survival did not correlate with clinically evident regional adenopathy, length of symptoms, extent of laryngeal surgery, or retrospective staging according to American Joint Committee guidelines on cancer of the larynx (AJC-1980). Distant metastatic spread occurred frequently and was the most common cause of death. Surgical therapy is currently the only effective treatment for primary or recurrent disease. Future treatment regimens must address distant spread of tumor.

Heparin monitoring in the coronary care unit after percutaneous transluminal coronary angioplasty.

The rate of acute restenosis in patients after percutaneous transluminal coronary angioplasty (PTCA) is related to thrombotic complications triggered by the PTCA. This risk is reduced by anticoagulating the patients with heparin after the procedure. The anticoagulation state of patients receiving heparin therapy is routinely monitored with the activated partial thromboplastin time (APTT) test. In an effort to provide more timely results regarding the status of patients who are receiving heparin after PTCA, a study was conducted to see whether low-range activated clotting time measurement (LR ACT) performed at the bedside could provide information comparable to that from APTT values determined in the laboratory. The study showed that the LR ACT values were comparable to laboratory-generated APTT values (R2 = 0.68). The LR ACT data generated were superior to the APTT data in terms of timeliness and the wider range of heparin levels covered. Having these values available allowed the CCU staff to react rapidly to changes in the patient's coagulation status.

Otolaryngology manifestation of postpolio syndrome.

Twenty-one patients with postpolio syndrome were surveyed to determine otolaryngologic symptoms. An alteration in voice, dysphagia, and fatigue were the most common symptoms reported. Prevailing etiologic theories are presented, and treatment recommendations are offered.

Tonsillar abscess.

This article presents seven cases of patients with tonsillar abscess formation and discusses the pathophysiology of intratonsillar abscess formation.

Airway manifestations of chondrodysplasia punctata.

Chondrodysplasia punctata is a heterogeneous skeletal dysplasia characterized by small focal calcifications in articular and other cartilages in infancy, referred to as stippled epiphyses, with subsequent epiphysial dysplasia and associated anomalies of the face, eyes and skin. Nasal hypoplasia is commonly seen but secondary respiratory distress is infrequently described. We present two siblings with different degrees of involvement and a review of the different forms of this disorder. When an infant presents with a small nasal airway, the diagnosis of chondrodysplasia punctata should be considered and appropriate evaluations obtained.

Eagle's syndrome: a reappraisal.

W.W. Eagle in 1937 described two patients with elongated styloid processes, cervico-facial pain and a history of pharyngeal trauma. Selected case reports are used to illustrate the spectrum of Eagle's Syndrome. An analysis of the prevailing theories of etiology and causation is undertaken correlating anatomy, embryology, and physiology to derive a clearer understanding of Eagle's Syndrome.