Role of limited parotidectomy in management of pleomorphic adenoma

There is continued controversy over the extent of parotidectomy required for removal of a benign pleomorphic adenoma from the parotid gland. Currently, consensus exists that the integrity of the facial nerve must be preserved when the tumour is totally removed.

As a result of experience gained in the first half of the twentieth century, it was recommended that superficial parotidectomy with facial nerve dissection should be the minimal biopsy for pleomorphic adenoma. Since that time, however, research has indicated that partial parotidectomy or extracapsular dissection of benign pleomorphic adenoma can be accomplished with preservation of the facial nerve without an increase in tumour recurrence. Partial parotidectomy or extracapsular dissection results in impaired cosmetic results and a lower incidence of Frey's syndrome, and thus may be the preferred approach when undertaken by experienced surgeons.

Sinonasal inverted papillomas: recurrence, and synchronous and metachronous malignancy

INTRODUCTION

Inverted papillomas are relatively rare, benign epithelial tumours of the nasal cavity which generate considerable interest because they are locally aggressive, have a tendency to recur and are associated with malignancy.

AIMS

To review our experience of the management of inverted papillomas, and to review the literature in order to evaluate recurrence rates, rates of synchronous and metachronous carcinoma, and outcomes of treatment, both endoscopic and conventional.

METHODS

We retrospectively reviewed all cases of inverted papilloma that presented to our unit, a tertiary referral centre, over a 20-year period from 1985 to 2005. A Medline review of the literature was performed to identify published case series of inverted papillomas. We undertook a critical analysis of the literature.

RESULTS

We treated 65 patients with inverted papilloma over the 20-year period, with a mean follow up of five years (range one to 20 years). Fifty-eight patients initially underwent nasal biopsy, often with polypectomy. Thirty-six had endoscopic surgery, with five (14 per cent) suffering recurrence, whilst 16 had a lateral rhinotomy and medial maxillectomy, of which four (25 per cent) suffered a recurrence. Seven septal inverted papillomas required local resection, with no subsequent recurrences. There were seven (11 per cent) synchronous and two metachronous malignancies.Sixty-three case series with adequate data were identified from the literature. There were 163 (7.1 per cent) cases of synchronous carcinoma, out of 2297 cases. Metachronous carcinomas were reported in 74 out of 2047 cases, representing a transformation rate of 3.6 per cent. However, the true population base for these figures is uncertain, given that many series were reported from tertiary centres, where recurrent and problematic cases are likely to be over-represented. The recurrence rates were 12.8 per cent for endoscopic procedures, 17.0 per cent for lateral rhinotomy with medial maxillectomy, and 34.2 per cent for limited resections such as nasal polypectomy and Caldwell-Luc approaches. No significant association between atypia or dysplasia and recurrence or malignant transformation was found. The mean time taken to develop a metachronous carcinoma was 52 months (range six to 180 months). The estimated malignant potential for recurrent disease was up to 11 per cent.

CONCLUSION

Patients with inverted papilloma should undergo thorough surgery to remove all mucosal disease, most probably by the endoscopic, endonasal route when complete resection is possible. Cases demonstrating atypia or dysplasia may be treated by the endoscopic route. Recurrent disease and metachronous carcinoma can develop after a prolonged period of time. Long-term follow up is recommended to detect recurrence, as disease can become quite extensive before it becomes symptomatic.

An audit of clinical resources available for the care of head and neck cancer patients in England

Objective: To undertake a postal survey of cancer networks to define the services available for the diagnosis, treatment and support of patients with head and neck cancer in England.

Findings: Thirty-four cancer networks are now responsible for the delivery of head and neck cancer services in England and 52 cancer units responded to our questionnaire. Multidisciplinary team working was evident in all centres. However such team working was not always fully staffed, especially in areas of national staff shortages such as pathology, radiology, dietetics and speech therapy. Rapid referral pathways were present for initial assessment of patients but clinically significant delays were identified in the provision of complex investigations, in access to intensive care beds and for oncological care – especially radiotherapy.

Conclusions: Major changes in service configuration are likely to be required if the current national targets of time to diagnosis and treatment are to be met.

Occult carotid pseudoaneurysm following streptococcal throat infection

Pseudoaneurysm of the internal carotid artery (PAICA) is a rare complication of neck space infection. An 8-year-old girl presented with odynophagia (painful swallowing), trismus and left peritonsillar swelling. Abscess was suspected, but aspiration was dry. The PAICA was diagnosed on computed tomography. The aneurysm and involved left internal carotid artery were occluded endovascularly. She has made an uneventful recovery.

An Audit of Clinical Resources Available for the Care of Head and Neck Cancer Patients in England

AIMS

Thirty-four cancer networks are now responsible for the delivery of head and neck cancer services in England. A survey of all cancer networks was carried out to define the services available for the diagnosis, treatment and support of patients with head and neck cancer.

MATERIALS AND METHODS

Fifty-two cancer units were identified in England from the Cancer Services Collaborative 'Improvement Partnership', and approached through a variety of methods. One questionnaire was circulated to all 34 network leads to establish the services and resources in each network. A second questionnaire was circulated to all known head and neck teams in the UK.

RESULTS

Multidisciplinary team (MDT) working was evident in all centres, although frequently the MDT was not fully staffed, especially in areas of national staff shortages, such as in pathology, radiology, dietetics and speech therapy. Rapid referral pathways were present for initial assessment of patients, but clinically significant delays were identified in complex investigations, access to intensive care beds and oncological care, especially radiotherapy.

CONCLUSION

Major changes in service configuration are likely to be required if the current national targets of time to diagnosis and treatment are to be met.

Nasal dermoid sinus cysts in adults

Nasal dermoid sinus cysts (NDSC) are rare congenital lesions that most frequently present in children, but have been reported in adults. This article reviews adult (more than 16 years of age) nasal dermoid sinus cysts as they present, their radiological investigation, surgical approach and outcome. Thirty-eight previously published cases are reviewed, to which a further six cases are added. All 44 cases are tabulated and reviewed. The risk of intracranial extension is 27.5 per cent, especially men with a dermal sinus. Recurrences are likely if the NDSC is not completely excised. Curative treatment is surgical. It is recommended that all adults who present with a dermal cyst and/or sinus in the region of the nasal dorsum should be investigated by computed tomography (CT) and/or magnetic resonance (MRI). This is to delineate deep tissue involvement and to exclude a possible associated intracranial extension, prior to recommending surgical excision.

Management of chronic parotitis: a review

Chronic parotitis is an insidious inflammatory disorder, which is characterized by a recurrent, often painful, swelling of the gland or glands. Sialography remains the investigation of choice. Diagnostic siladenoscopy may complement or supersede sialography as the diagnostic procedure of choice, as more experience is gained in this technique and its use becomes more widespread. The management options are conservative or surgical, but controversy exists regarding the timing and method of surgical intervention. The surgical methods that have been described include injection of methyl violet - a sclerosing agent, ductal ligation, ductoplasty, tympanic neurectomy, and parotidectomy. Parotidectomy is considered the ultimate surgical option but because of its significant morbidity the exact technique and procedure that should be used remains contentious.

Are autopsies useful? Do premorbid findings predict postmortem results in head and neck cancer patients?

A total of 53 autopsies were analysed in patients with head and neck squamous carcinoma. The discordance rate, that is the proportion of autopsies that revealed new information, was 53%. One-third of patients did not die of cancer. Clinical findings either misdiagnosed or under-diagnosed loco regional disease in 34% of cases, and distant malignant disease in 36% of cases. It appears that the autopsy reveals new and useful information in the head and neck cancer patient, and consent should be sought.

Aggressive sino-nasal non-Hodgkin's lymphoma diagnosed in Nottinghamshire, UK, between 1987 and 1996

In the 10-year period 1987 to 1996, 24 patients were diagnosed with aggressive non-Hodgkin's lymphoma of the nasal cavities or paranasal sinuses. The disease occurred in a relatively elderly population of median age 72 years (range 42 to 96) with a male predominance (male 15; female nine). The histology on review was mostly of the large B-cell subtype (21 patients); peripheral T-cell subtype (one), anaplastic large cell of T-cell type (one) and T/natural killer cell nasal lymphoma (one). The disease was localized in 20 patients (Stage IEA). The overall survival at 5 years was 40% (95% confidence interval (CI) 19-61); at 10 years it was 33% (95% CI 12-54). The cause-specific survival (excluding deaths from causes other than lymphoma) at 5 years and 10 years was 62% (95% CI 39-86).

Pilomatrixoma in the parotid region

Pilomatrixoma is a benign neoplasm of the hair follicle that may present to the otolaryngologist as a palpable swelling in the head and neck area. The correct diagnosis may be difficult to confirm when it presents in the region of the parotid. The use of fine needle aspiration cytology (FNAC) and diagnostic imaging may help confirm the diagnosis. The correct treatment is surgical. However, should the tumour recur then the possibility of malignancy should be considered.

The pro region of Toxoplasma ROP1 is a rhoptry-targeting signal

The rhoptries of Toxoplasma gondii are regulated secretory organelles involved in the invasion of host cells. Rhoptry proteins are synthesised as pre-pro-proteins that are processed first to pro-proteins upon entrance into the secretory pathway, then processed again to their mature forms late in the secretory pathway. The pro-mature processing site of the rhoptry protein ROP1 has been determined, paving the way for understanding the role of the pro region in rhoptry protein function. We demonstrate here that the ROP1 pro region is sufficient for targeting a reporter protein (amino acids 34-471 of the Trypanosoma brucei VSG117 protein) to the rhoptries. These results, together with our previous work showing that rhoptry targeting is unaffected by deletion of the pro region, indicate that the ROP1 protein contains at least two signals that can function in rhoptry targeting.

Benign salivary gland disease

The majority of benign clinical problems that present affect the major salivary glands--parotid and submandibular. However, there are numerous minor salivary glands located in the mucosa of the head and neck which have the same predilection to the same diseases that affect the major glands but to a lesser frequency.

Distant metastases from salivary glands cancer

Patients who present with malignant salivary glands should at their initial assessment have an X-ray of the chest to exclude the possibility of distant metastases. Patients who have other symptoms, bone pain etc., should be appropriately investigated. The likelihood of patients developing distant metastases is associated with high-grade tumors, most commonly adenoid cystic carcinoma, high-grade mucoepidermoid carcinoma, salivary duct carcinoma and tumors sited in the submandibular gland, posterior tongue and pharyngeal tumors. Patients who have had a high-grade tumor treated and survived without locoregional recurrence have the same risk of developing distant metastases as those patients who have locoregional recurrence. Other histological types of salivary tumors are associated with a lower risk of developing distant metastases but a real risk remains lifelong. It is recommended that all patients who have a malignant salivary gland tumor treated, any histology, should be followed up and clinically assessed at least once every 12 months for life.

MIB-1 and p53 expression in radiotherapy-resistant T1aN0M0 glottic squamous cell carcinoma

Radiotherapy of T1aN0M0 glottic carcinoma results in a local control rate of 80-94%. This homogenous group, which is the earliest recognisable invasive malignancy in the head and neck region, provides a 'unique model' for studying possible biological markers of radiosensitivity. p53 and MIB-1 were investigated as possible markers of radiosensitivity in such a group. In all, 107 patients with T1aN0M0 glottic squamous cell carcinoma treated with radiotherapy were identified. Cases not responsive to radiotherapy were compared with matched radiosensitive controls by immunohistochemistry using monoclonal primary antibodies to MIB-1 (n = 18; controls = 10) and p53 (n = 6; controls = 11). No significant difference in p53 expression was noted between the two groups (P = 0.73). A greater MIB-1 expression was found in the radiosensitive group but only a trend towards significance was observed (P = 0.06). MIB-1 is a potential marker of radiosensitivity. A larger multicentre study is required for a more definitive answer.

A randomised clinical trial of turbinectomy for compensatory turbinate hypertrophy in patients with anterior septal deviations

Turbinectomy is performed at the time of nasal septal surgery by many otolaryngologists. One reason given for this procedure is the presence of a hypertrophied contralateral inferior turbinate. A randomised trial was undertaken to evaluate the relief of nasal obstruction following contralateral turbinectomy with septal surgery. Patients presenting with nasal obstruction who had a unilateral septal deviation and contralateral inferior turbinate enlargement were prospectively randomized to contralateral turbinectomy or no turbinate surgery at the time of septal surgery. Questionnaires and active anterior rhinomanometry were used for evaluation. Twenty-six patients (mean age 31 years) demonstrated a reduction in subjective and objective measures of nasal obstruction (P < 0.05) 8 weeks after operation. There was no intergroup difference, the median total decongested nasal resistance postoperatively in the non-turbinectomized patients was 0.17 kPal-1 s and 0.21 kPal-1 s in the turbinectomized patients. Contralateral inferior turbinectomy does not add to the relief of nasal obstruction beyond that attained by septal surgery in these patients.

Toxoplasma gondii homologue of plasmodium apical membrane antigen 1 is involved in invasion of host cells

Proteins with constitutive or transient localization on the surface of Apicomplexa parasites are of particular interest for their potential role in the invasion of host cells. We describe the identification and characterization of TgAMA1, the Toxoplasma gondii homolog of the Plasmodium apical membrane antigen 1 (AMA1), which has been shown to elicit a protective immune response against merozoites dependent on the correct pairing of its numerous disulfide bonds. TgAMA1 shows between 19% (Plasmodium berghei) and 26% (Plasmodium yoelii) overall identity to the different Plasmodium AMA1 homologs and has a conserved arrangement of 16 cysteine residues and a putative transmembrane domain, indicating a similar architecture. The single-copy TgAMA1 gene is interrupted by seven introns and is transcribed into an mRNA of approximately 3.3 kb. The TgAMA1 protein is produced during intracellular tachyzoite replication and initially localizes to the micronemes, as determined by immunofluorescence assay and immunoelectron microscopy. Upon release of mature tachyzoites, TgAMA1 is found distributed predominantly on the apical end of the parasite surface. A approximately 54-kDa cleavage product of the large ectodomain is continuously released into the medium by extracellular parasites. Mouse antiserum against recombinant TgAMA1 blocked invasion of new host cells by approximately 40%. This and our inability to produce a viable TgAMA1 knock-out mutant indicate that this phylogenetically conserved protein fulfills a key function in the invasion of host cells by extracellular T. gondii tachyzoites.

Non-Hodgkin's lymphoma of the sinonasal tract

OBJECTIVES

A review of the presenting features, management, and outcome of extranodal non-Hodgkin's lymphoma (NHL) of the sinonasal tract during a 10-year period in Nottingham, UK.

STUDY DESIGN

Twenty-four patients received a diagnosis of extranodal NHL of the nasal cavity, paranasal sinuses, or both, from 1987 to 1996. The patients' data were collected prospectively in the Nottinghamshire Lymphoma Registry.

METHODS

All patients' records and their histology were reviewed along with data entered into the Nottinghamshire Lymphoma Registry, noting the patient's age, sex, presenting symptoms and signs, staging, computed tomography findings, histology, treatment, complications, and outcome.

RESULTS

The 24 patients with extranodal NHL of the sinonasal tract represent 1.63% of the 1,457 patients with NHL seen in the 10-year period of this study in Nottinghamshire. The median age was 72 years (range, 42-96 y), with a male dominance (male-to-female ratio: 15:9). Most patients presented with nonspecific nasal symptoms such as nasal obstruction and epistaxis. Only one patient had a relapse involving the central nervous system after treatment. All the histology was reviewed and showed a predominance of large B-cell subtype (21 patients). The overall 5-year survival was 40% (95% CI, 19%-61%) and 33% for 10-year (95% CI, 12%-54%). The cause-specific survival at 5 years and 10 years was 62% (95% CI, 39%-86%).

CONCLUSIONS

A high degree of suspicion and appropriate use of computed tomography scans and surgical biopsy are the keys to the management of NHL.

Presence of a member of the mitochondrial carrier family in hydrogenosomes: conservation of membrane-targeting pathways between hydrogenosomes and mitochondria

A number of microaerophilic eukaryotes lack mitochondria but possess another organelle involved in energy metabolism, the hydrogenosome. Limited phylogenetic analyses of nuclear genes support a common origin for these two organelles. We have identified a protein of the mitochondrial carrier family in the hydrogenosome of Trichomonas vaginalis and have shown that this protein, Hmp31, is phylogenetically related to the mitochondrial ADP-ATP carrier (AAC). We demonstrate that the hydrogenosomal AAC can be targeted to the inner membrane of mitochondria isolated from Saccharomyces cerevisiae through the Tim9-Tim10 import pathway used for the assembly of mitochondrial carrier proteins. Conversely, yeast mitochondrial AAC can be targeted into the membranes of hydrogenosomes. The hydrogenosomal AAC contains a cleavable, N-terminal presequence; however, this sequence is not necessary for targeting the protein to the organelle. These data indicate that the membrane-targeting signal(s) for hydrogenosomal AAC is internal, similar to that found for mitochondrial carrier proteins. Our findings indicate that the membrane carriers and membrane protein-targeting machinery of hydrogenosomes and mitochondria have a common evolutionary origin. Together, they provide strong evidence that a single endosymbiont evolved into a progenitor organelle in early eukaryotic cells that ultimately give rise to these two distinct organelles and support the hydrogen hypothesis for the origin of the eukaryotic cell.

Competition and protease sensitivity assays provide evidence for the existence of a hydrogenosomal protein import machinery in Trichomonas vaginalis

Hydrogenosomes are double membrane bounded redox organelles found in a number of amitochondriate protists and fungi. They are involved in carbohydrate metabolism and ATP synthesis and thus resemble mitochondria. Molecular analysis of the hydrogenosomal heat shock proteins Hsp70, Hsp60 and Hsp10 in Trichomonas vaginalis, one of the deepest-branching eukaryotes known to date, has revealed that these group exclusively with mitochondrial heat shock proteins. This finding indicates strongly that a progenitor organelle which gave rise to contemporary mitochondria and hydrogenosomes existed early in eukaryotic life. This hypothesis is further supported by similarities of hydrogenosomal and mitochondrial biogenesis. It was shown that T. vaginalis hydrogenosomal proteins are synthesized on free ribosomes in the cytosol with an N-terminal presequence that carries targeting information and is cleaved upon import into the organelle. Furthermore, as in mitochondrial import, hydrogenosomal protein import requires ATP, an electrochemical transmembrane potential and cytosolic protein factor(s). Here we demonstrate that inhibition of hydrogenosomal protein import occurs (i) in the presence of a synthetic presequence peptide and (ii) after pretreatment of hydrogenosomes with the protease trypsin. Trypsin pretreatment affects two hydrogenosomal membrane proteins of 31 and 70 kDa, respectively. Thus, we present evidence that import is saturable and that proteinaceous hydrogenosomal import receptor(s) exist. These results are a first step towards a characterization of the hydrogenosomal import machinery which should provide further insights into the relationship of hydrogenosomes and mitochondria and the evolution of protein targeting into organelles of endosymbiotic origin.

Pharyngeal pouch carcinoma: real or imaginary risks?

Pharyngeal pouch or Zenker's diverticulum presents to the otolaryngologist with symptoms of dysphagia. As supported by the published literature, the condition is more frequently seen in Northern Europe, especially the United Kingdom, than elsewhere in the world. The cause of the reported increased incidence in the United Kingdom is not known, but may be dietary. Surgical management is the treatment of choice and is directed at the cricopharyngeus muscle by either an external or an internal approach. There is a real risk of carcinoma or carcinoma in situ developing in a treated or untreated pharyngeal pouch. Excision of the pouch sac is recommended in younger patients, less than 65 years, and in patients who have a large pouch. If endoscopic diverticulotomy is performed, then long-term patient symptom follow-up is to be advocated.

Frey's syndrome following parotidectomy: prevention using a rotation sternocleidomastoid muscle flap

The benefit of using a sternocleidomastoid flap following parotidectomy to reduce the incidence of symptomatic gustatory sweating (Frey's syndrome) was reviewed. A retrospective study was undertaken to review subjective and objective symptoms of Frey's syndrome in two groups of patients, one of whom had undergone superficial parotidectomy with a sternocleidomastoid flap rotated at the time of surgery and a second group of patients who had undergone a standard superficial parotidectomy. A total of 22 patients, randomly sampled and willing to attend, were evaluated postoperatively, at a median time from surgery of 42 months (range 23-82 months) in the non-flap group and 44 months (range 14-66 months) in the flap group, by Minor's starch iodine test. In the 11 patients who had a sternocleidomastoid flap rotated, two had evidence of gustatory sweating. Of the 11 that had not undergone sternocleidomastoid flap rotation, nine patients showed evidence of gustatory sweating (P < 0.05, chi 2 test). There were two patients in total who had clinical symptoms of Frey's syndrome and both of these had not undergone flap rotation at the time of parotidectomy.

Identification of the pro-mature processing site of Toxoplasma ROP1 by mass spectrometry

The rhoptries are specialized secretory organelles that function during host cell invasion in the obligate intracellular parasite Toxoplasma gondii. All T. gondii rhoptry proteins studied to date are synthesized as pro-proteins that are then processed to their mature forms. To understand the role of the pro region in rhoptry protein function, we have precisely defined the processing site of the pro-region of the rhoptry protein ROP1. Efforts to determine such processing sites have been prevented by blocked N-termini of mature proteins isolated from T. gondii. To overcome this problem, we have used an engineered form of ROP1 and mass spectrometry to demonstrate that proROP1 is processed to its mature form between the glutamic acid at position 83 and alanine at position 84. These data also show that mature ROP1 lacks substantial post-translational modifications, a result which has important implications for targeting of rhoptry proteins.

Treatment of the patient with upper airway obstruction caused by cancer of the larynx

The treatment of a patient with imminent airway obstruction caused by a malignant tumor of the larynx is an uncommon clinical problem. These cases need to be evaluated, diagnosed, and managed with care, skill, speed, and above all, appropriateness of intervention. Three methods are available to control the airway: tracheostomy, emergency laryngectomy, and controlled tracheal intubation with or without tumor debulking. Two groups of patients had their airways managed either by tracheostomy and delayed elective surgery or by emergency laryngectomy. There was no survival advantage between the groups, and no increased risk of stomal recurrence was demonstrated. If time permits, the patient is considered suitable, and adequate anesthetic and surgical instrumentation is available, it is currently recommended that the obstructing laryngeal tumor be debulked by cold-steel or, preferably, CO2 laser and that the emergency situation be stabilized and the definitive treatment of the patient be converted to an elective procedure without the need to create a tracheostomy.

Nucleocapsid protein zinc-finger mutants of simian immunodeficiency virus strain mne produce virions that are replication defective in vitro and in vivo

All retroviruses (except the spumaretroviruses) contain a nucleocapsid (NC) protein that encodes one or two copies of the Zn2+-finger sequence -Cys-X2-Cys-X4-His-X4-Cys-. This region has been shown to be essential for recognition and packaging of the genomic RNA during virion particle assembly. Additionally, this region has been shown to be involved in early infection events in a wide spectrum of retroviruses, including mammalian type C [e.g., murine leukemia virus (MuLV)], human immunodeficiency virus type 1 (HIV-1), Rous sarcoma virus, and other retroviruses. Mutations in the two Zn2+-fingers of the NC protein of simian immunodeficiency virus strain Mne [SIV(Mne)] have been generated. The resulting virions contained the normal complement of processed viral proteins with densities indistinguishable from wild-type SIV(Mne). All of the mutants had electron micrograph morphologies similar to those of immature particles observed in wild-type preparations. RNA packaging was less affected by mutations in the NC protein of SIV(Mne) than has been observed for similar mutants in the MuLV and HIV-1 systems. Nevertheless, in vitro replication of SIV(Mne) NC mutants was impaired to levels comparable to those observed for MuLV and HIV-1 NC mutants; replication defective NC mutants are typically 10(5)- to 10(6)-fold less infectious than similar levels of wild-type virus. One mutant, DeltaCys33-Cys36, was also found to be noninfectious in vivo when mutant virus was administered intravenously to a pig-tailed macaque. NC mutations can therefore be used to generate replication defective virions for candidate vaccines in the SIV macaque model for primate lentiviral diseases.

ENT pathology and diplopia

ENT pathology causes diplopia in a minority of patients. Because the various ENT conditions that can produce diplopia are relatively unusual they often escape early detection. We describe the various ENT disorders that can produce diplopia and illustrate this with our experience between 1992 and 1998. We wish to emphasise the benefit which can be obtained from undertaking an ENT history and examination in arriving at the correct diagnosis.

Targeting and translocation of proteins into the hydrogenosome of the protist Trichomonas: similarities with mitochondrial protein import

Trichomonads are early-diverging eukaryotes that lack both mitochondria and peroxisomes. They do contain a double membrane-bound organelle, called the hydrogenosome, that metabolizes pyruvate and produces ATP. To address the origin and biological nature of hydrogenosomes, we have established an in vitro protein import assay. Using purified hydrogenosomes and radiolabeled hydrogenosomal precursor ferredoxin (pFd), we demonstrate that protein import requires intact organelles, ATP and N-ethylmaleimide-sensitive cytosolic factors. Protein import is also affected by high concentrations of the protonophore, m-chlorophenylhydrazone (CCCP). Binding and translocation of pFd into hydrogenosomes requires the presence of an eight amino acid N-terminal presequence that is similar to presequences found on all examined hydrogenosomal proteins. Upon import, pFd is processed to a size consistent with cleavage of the presequence. Mutation of a conserved leucine at position 2 in the presequence to a glycine disrupts import of pFd into the organelle. Interestingly, a comparison of hydrogenosomal and mitochondrial protein presequences reveals striking similarities. These data indicate that mechanisms underlying protein targeting and biogenesis of hydrogenosomes and mitochondria are similar, consistent with the notion that these two organelles arose from a common endosymbiont.

The role of endoscopy in the management of nasal neoplasia

Fiberoptic endoscopy has made a notable impact in rhinology over the last decade, mainly in the diagnosis and treatment of paranasal sinus inflammatory disease. The aim of this article is to review, discuss, and illustrate the role of endoscopy in the management of nasal neoplasia. We have reviewed our own experience and illustrate this with four cases. We discuss the role of endoscopy in the diagnosis, biopsy, resection, posttherapeutic surveillance, and palliation of these tumors.

Students Practice Essential Components of Community Health Nursing in Home Health Care

Because home health differs from community health nursing, using home health agencies as clinical sites to teach community health nursing may be inappropriate. This retrospective descriptive study compared the perceptions of students who took community health before it included a home health placement with those whose course included home health. Mailed surveys were returned from 28(63.6%) of the 44 students enrolled prior to the home health placements and from 30(60%) of the 50 students enrolled afterwards. Students whose experience included home health rated the home visit experience significantly better in terms of providing them an opportunity to perform health promotion and to care for family as client. They found the course more relevant, felt safer in making home visits, and were more likely to consider working in community health nursing. This study supports using home health agencies as clinical placements for community health nursing if they are supplemented with aggregate-level experiences.

A common evolutionary origin for mitochondria and hydrogenosomes

Trichomonads are among the earliest eukaryotes to diverge from the main line of eukaryotic descent. Keeping with their ancient nature, these facultative anaerobic protists lack two "hallmark" organelles found in most eukaryotes: mitochondria and peroxisomes. Trichomonads do, however, contain an unusual organelle involved in carbohydrate metabolism called the hydrogenosome. Like mitochondria, hydrogenosomes are double-membrane bounded organelles that produce ATP using pyruvate as the primary substrate. Hydrogenosomes are, however, markedly different from mitochondria as they lack DNA, cytochromes and the citric acid cycle. Instead, they contain enzymes typically found in anaerobic bacteria and are capable of producing molecular hydrogen. We show here that hydrogenosomes contain heat shock proteins, Hsp70, Hsp60, and Hsp10, with signature sequences that are conserved only in mitochondrial and alpha-Gram-negative purple bacterial Hsps. Biochemical analysis of hydrogenosomal Hsp60 shows that the mature protein isolated from the organelle lacks a short, N-terminal sequence, similar to that observed for most nuclear-encoded mitochondrial matrix proteins. Moreover, phylogenetic analyses of hydrogenosomal Hsp70, Hsp60, and Hsp10 show that these proteins branch within a monophyletic group composed exclusively of mitochondrial homologues. These data establish that mitochondria and hydrogenosomes have a common eubacterial ancestor and imply that the earliest-branching eukaryotes contained the endosymbiont that gave rise to mitochondria in higher eukaryotes.

Issues inherent in measuring the impact of care coordination on pregnancy outcomes

Care coordination is a Medicaid benefit designed to help low-income women gain access to pregnancy-related services. Measuring the outcomes of care coordination is hampered because experimental designs are difficult to carry out on entitlement programs. The purpose of this study was to examine whether a care coordination-adequacy index, based on number of home visits, onset of home visits, and weeks' gestation at delivery, would outperform a simple count of the number of home visits in predicting birthweight. Data from a pilot project in Indianapolis were used. The adequacy index outperformed "number of home visits" in the prediction of birthweight with this sample. Those who received intermediate level of care coordination delivered infants weighing 162 g more than those who received inadequate care coordination. The adequate level of care coordination did not predict birthweight, which may have resulted from an insufficient number of participants in this category (n = 20). An inherent selection bias based on the length of gestation when admitted to the program is also discussed. Research on care coordination with clear delineation of the measurement issues involved must continue to ensure effective program design and continued funding.

The Netherlands' Maternal-Child Health Program: implications for the United States

The Netherlands has infant mortality rates that are consistently lower than those of the United States. The United States ranked 22nd in infant mortality in 1989, whereas the Netherlands ranked 5th. Several components of the Dutch health care system could be adapted in the United States to lower the infant mortality rate. The maternity care helper program is one such service.

Home healthcare nurses should regain their family focus

A study was conducted to examine how frequently family caregivers of home care clients may be potentially eligible for Medicare-reimbursable home health services. In a sample of 51 family caregivers, 90% had health-teaching needs, 94% needed referrals, and 28% were potentially eligible to receive Medicare-reimburseable home health services.

Carcinoma of the larynx and hypopharynx in the elderly

The outcome of a series of 68 patients over 75 years old with carcinoma of the larynx, and 33 patients over 75 years old with hypopharyngeal carcinoma managed by a single oncological team during a 10-year period was studied. Sixty-one of the patients with laryngeal carcinoma were treated with curative intent. The actuarial 3-year survival rate of the whole group was 45%. This contrasts with hypopharyngeal carcinoma in which we found a 3-year survival of 11% with only 17 of the 33 patients suitable for treatment with curative intent. In view of the anticipated poor prognosis of hypopharyngeal carcinoma in the elderly we conclude that treatment should be directed towards palliation without radical surgery whenever possible.

Langerhans' cell histiocytosis: head and neck manifestations in children

BACKGROUND

Langerhans' cell histiocytosis (LCH) is an uncommon, poorly understood granulomatous disease, characterized by the idiopathic proliferation of Langerhan's cells or their marrow precursors. In 1985, the Philadelphia Work-shop adopted the term "Langerhans' cell histiocytosis" (LCH) to differentiate it from reactive and neoplastic causes of histiocytosis.

METHODS

This study includes 73 pediatric patients diagnosed with this condition in Dublin, Ireland, and Nottingham, England, during a 34-year period (1959 to 1993). These patients are reviewed with respect to clinical presentation, difficulty with making a histological diagnosis, their management, and outcome.

RESULTS

A total of 49 patients (67%) had head and neck involvement. Bony involvement was the most frequent sign, most frequently located in the skull. There were 11 deaths (15%) in this series, all associated with multisystem disease, and nine of these deaths were in children younger than 2 years of age.

CONCLUSIONS

The role of otolaryngologists is important in the early and accurate evaluation, staging, and diagnosis of LCH. It may mimic more common diseases, such as otitis externa, acute mastoiditis, skin rash, gingivitis, or cervical lymphadenopathy. Patients with multisystem disease may be so ill at presentation that the head and neck lesions may be overlooked. The current management of LCH has become increasingly conservative, and in the 1990s, fewer cases are given chemotherapy or radiotherapy. The prognosis is very good for single-system disease and poor for multisystem disseminated disease with early onset.

The impact of home visits on enrollment patterns in pregnancy-related services among low-income women

Medicaid now reimburses for care-coordination services for pregnant women in about half of the states. This care-coordination project targeted low-income pregnant women in two Indianapolis neighborhoods that historically have had high black-infant mortality rates. The service provided home visits by teams of workers including registered nurses, social workers, and indigenous community health workers. This retrospective descriptive study evaluated the impact of the home visits on enrollment in pregnancy-related services. Data were collected from the care-coordination records of 381 participants who delivered infants between July 1, 1990, and January 1, 1992. The proportion of participants enrolled in prenatal care, the Special Supplemental Food Program for Women, Infants and Children (WIC), Medicaid, and Food Stamps increased significantly following admission to care coordination. The majority of participants who enrolled in prenatal care and WIC, after admission to care coordination, did so within one month of admission. Home visits were effective in stimulating enrollment in pregnancy-related services. Further studies need to be done to evaluate the impact of home visits on pregnancy outcomes as well as their cost-effectiveness.

Tumor-associated tissue eosinophilia and long-term prognosis for carcinoma of the larynx

Tumor-associated tissue eosinophilia (TATE) has been previously reported to be associated with a favorable prognosis for a variety of carcinomas, including head and neck cancer. We have examined this relationship in a series of 104 patients with laryngeal cancer who were observed for 5 years or more. Patients were followed up for a minimum of 5 years or until death. The original laryngeal biopsy histologic slides were examined and graded for TATE. Tumor-associated tissue eosinophilia was absent in 73 of the 104 biopsy specimens, and 25 of these 73 patients died directly of laryngeal carcinoma within 5 years. In all, 31 patients had TATE and only 3 subsequently died of laryngeal carcinoma within 5 years (P = 0.009, chi-square test). It appears, therefore, that TATE is associated with a good long-term prognosis for laryngeal carcinoma.

Molecular characterization of the alpha-subunit of Trichomonas vaginalis hydrogenosomal succinyl CoA synthetase

The anaerobic, parasitic protist, Trichomonas vaginalis, is characterized by the absence of mitochondria and the presence of double membrane bound organelles called hydrogenosomes. Succinyl-coenzyme A synthetase is a hydrogenosomal enzyme which catalyzes the formation of ATP via substrate-level phosphorylation. We have characterized genes encoding the alpha subunit of the hydrogenosomal protein succinyl-coenzyme A synthetase (SCS). The alpha-SCS of T. vaginalis is encoded by a multigene family composed of 3 similar genes that do not appear allelic. These 3 alpha-SCS genes encode a protein with a calculated molecular mass of approximately 32.5 kDa that has > 50% identity (> 70% similarity with alpha-SCSs from Escherichia coli, Thermus flavus, and rat liver mitochondria. Antibodies raised against recombinant T vaginalis alpha-SCS expressed in bacteria were used to isolate alpha-SCS proteins from purified hydrogenosomes. These proteins partition into the soluble fraction of hydrogenosomes treated with sodium carbonate at high pH, consistent with a matrix localization in the organelle. Amino-terminal sequencing of purified alpha-SCS proteins shows that mature proteins lack a short, leader sequence of 9 amino acids. These amino terminal sequences which are cleaved from T. vaginalis alpha-SCSs are similar to each other and to all other leader sequences identifed on hydrogenosomal proteins.

The Nottingham System: objective assessment of facial nerve function in the clinic

The House-Brackmann is the most widely accepted system for the clinical assessment of facial nerve function. It is, however, being subjective and discontinuous, prone to interobserver variation. The need for an objective system persists. The Nottingham System is described and compared to the Burres-Fisch system in a study of 29 subjects with varying degrees of facial nerve function, ranging from normal to total paralysis. Within-group component of variance analysis was 7% for the Nottingham System compared to 26% for the Burres-Fisch system. Bland and Altmans' analysis showed the Burres-Fisch system to be biased, overestimating small percentage scores, and underestimating large ones. The Nottingham System proved unbiased. The Nottingham System is recommended as an accurate objective continuous grading system for the rapid assessment of facial nerve function in the clinic.

Biogenesis of the hydrogenosome in the anaerobic protist Trichomonas vaginalis

Trichomonas vaginalis is a primitive protist that lacks mitochondria and peroxisomes. This aerotolerant anaerobe does, however, contain a specialized organelle involved in carbohydrate metabolism called the hydrogenosome. Hydrogenosomes are the site of fermentative oxidation of pyruvate, coupled to ATP production via substrate level phosphorylation. The organelle is surrounded by 2 membranes and appears to contain no genetic material. Hydrogenosomes are proposed to have arisen either through the conversion of mitochondria or via endosymbiosis with an anaerobic bacterium. Our studies show that hydrogenosomal proteins are synthesized on free polyribosomes and are, thus, posttranslationally translocated into the organelle. The 2 hydrogenosomal proteins we have examined in detail, ferredoxin and the beta subunit of succinyl CoA synthetase, appear to be synthesized as larger precursors that contain an 8- or 9-amino acid amino-terminal extension, respectively. These apparent leader sequences are absent from the mature proteins found in hydrogenosomes. The biochemical properties of the amino-terminal extensions are similar to one another and to mitochondrial presequences. These observations are consistent with the hypotheses that the specificity of protein translocation into hydrogenosomes is conferred by a short amino-terminal signal sequence and that the mechanisms underlying translocation are similar to that of mitochondria. Using in vitro import assays, we have shown that this short leader sequence is absolutely required for association of hydrogenosomal proteins with the organelle and that this association is dependent on ATP, temperature, and the presence of intact organelles.