Radiological features of unusual ingested foreign bodies.

For patients who ingest foreign bodies, pre-operative radiography is an invaluable tool that allows the surgeon to confirm the presence of the foreign body, preempt potential difficulties and plan the best method for foreign body removal. This is particularly important when a foreign body is of usual shape and size. We present a series of radiographs and pictures of some of the retrieved foreign bodies of five patients who swallowed unusual foreign bodies.

Recurrent nasopharyngeal carcinoma presenting as diffuse dermal lymphatic infiltration in the neck: three case reports.

BACKGROUND: Any malignancy has the propensity to metastasize to skin. The frequency of skin metastases vary in different tumors and occur in about 0.7% to 10% of all patients diagnosed with cancer. It is rare in nasopharyngeal carcinoma. METHOD: Three cases of relapsed nasopharyngeal carcinoma with diffuse dermal involvement were described. Their clinical presentation, results of investigations, and response to treatment were reviewed. Literature review of similar forms of presentation was done by means of a MEDLINE search. RESULTS: At the time of dermal relapse, all three patients had a uniform clinical picture of facial, periorbital, and lip swelling associated with stridor and dysphagia. Histologic findings showed dermal infiltrates of malignant cells, and CT scan showed diffuse infiltration of the subcutaneous tissue. Despite chemotherapy, the clinical course was relentless. CONCLUSION: This report describes a presentation of disease that is underdiagnosed and heightens awareness of oncologists to this form of recurrence in nasopharyngeal carcinoma.

Features of the parkin/ariadne-like ubiquitin ligase, HHARI, that regulate its interaction with the ubiquitin-conjugating enzyme, Ubch7.

We recently reported the identification of a RING finger-containing protein, HHARI (human homologue of Drosophila ariadne), which binds to the human ubiquitin-conjugating enzyme UbcH7 in vitro. We now demonstrate that HHARI interacts and co-localizes with UbcH7 in mammalian cells, particularly in the perinuclear region. We have further defined a minimal interaction region of HHARI comprising residues 186-254, identified individual amino acid residues essential for the interaction, and determined that the distance between the RING1 finger and IBR (in between RING fingers) domains is critical to maintaining binding. We have also established that the RING1 finger of HHARI cannot be substituted for by the highly homologous RING finger domains of either of the ubiquitin-protein ligase components c-CBL or Parkin, despite their similarity in structure and their independent capabilities to bind UbcH7. Furthermore, mutation of the RING1 finger domain of HHARI from a RING-HC to a RING-H2 type abolishes interaction with UbcH7. These studies demonstrate that very subtle changes to the domains that regulate recognition between highly conserved components of the ubiquitin pathway can dramatically affect their ability to interact.

Characterisation of the human and mouse orthologues of the Drosophila ariadne gene.

The specificity of the ubiquitin degradation system is regulated through interaction between individual ubiquitin-conjugating enzymes (E2s) and multiple ubiquitin-protein ligases (E3s). Here we describe the characterisation of a novel gene (ARIH1) that encodes the human homologue of Drosophila ariadne which interacts with the E2s, UbcH7 and UbcH8 and represents a component of an E3 complex. Three PACs (189N19, 142P17 and 179H7) were isolated that contain this gene. Using these PACs as probes, we mapped ARIH1 to human chromosome 15q24 by fluorescence in situ hybridisation (FISH). Sequencing of the ARIH1 PACs showed that the gene has 13 introns. In addition, we isolated two PACs (345D8 and 571P19) containing the mouse orthologue (Arih1) of ARIH1. The intron-exon structure of Arih1 was identical to ARIH1 and the proteins demonstrated a 98% identity at the amino acid level. Furthermore, comparison of Drosophila ariadne with ARIH1 indicates an identity at the amino acid level of 70% and introns at 3/7 identical sites. The high degree of homology demonstrated by the mouse and human orthologues of Drosophila ariadne indicates an important, conserved biological function, consistent with a putative role in ubiquitylation.

Anaerobic biodegradability of alkylphenols and fuel oxygenates in the presence of alternative electron acceptors.

Alkylphenols and fuel oxygenates are important environmental pollutants produced by the petrochemical industry. A batch biodegradability test was conducted with selected ortho-substituted alkylphenols (2-cresol, 2,6-dimethylphenol and 2-ethylphenol), fuel oxygenates (methyl tert-butyl ether, ethyl tert-butyl ether and tert-amylmethyl ether) and tert-butyl alcohol (TBA) as model compounds. The ortho-substituted alkylphenols were not biodegraded after 100 days of incubation under methanogenic, sulfate-, or nitrate-reducing conditions. However, biodegradation of 2-cresol and 2-ethylphenol (150 mg l(-1)) was observed in the presence of Mn (IV) as electron acceptor. The biodegradation of these two compounds took place in less than 15 days and more than 90% removal was observed for both compounds. Mineralization was indicated since no UV-absorbing metabolites accumulated after 23 days of incubation. These alkylphenols were also slowly chemically oxidized by Mn (IV). No biodegradation of fuel oxygenates or TBA (1 g l(-1)) was observed after 80 or more days of incubation under methanogenic, Fe (III)-, or Mn (IV)-reducing conditions, suggesting that these compounds are recalcitrant under anaerobic conditions. The fuel oxygenates caused no toxicity towards acetoclastic methanogens activity in anaerobic granular sludge.

Lymphocytic infiltration in undifferentiated nasopharyngeal cancer.

BACKGROUND: Undifferentiated nasopharyngeal carcinoma (NPC) is characterized by prominent lymphocytic infiltration. Although the lymphoid infiltrate in NPC has been examined extensively in morphologic and immunocytochemical studies, the significance of this lymphoid infiltrate and its correlation with prognosis has been a subject of controversy for years. OBJECTIVE: To elucidate the significance of lymphoid infiltration in undifferentiated NPC. DESIGN: Evaluation of the relationship between lymphocytic infiltration in NPC and cervical lymph node status, ultrastructural examination of the lymphoid infiltrate, and assessment of lymphocytic infiltration as an independent prognosticator of regional node metastasis. MATERIALS AND METHODS: Lymphocytic infiltration was evaluated quantitatively in 20 cases of undifferentiated NPC using light microscopy. Four cases of undifferentiated NPC were processed for conventional electron microscopy. The effects of degree of lymphocytic infiltration, age, and tumor stage on cervical nodal metastasis were analysed using the logistic regression model. RESULTS: The degree of lymphoid infiltration correlated with cervical nodal metastasis (P<.001). Ultrastructural evidence of lymphocytes destroying cancer cells was seen. Lymphocytic infiltration was found to be an independent factor affecting cervical nodal metastasis (P =.02, univariate analysis; P =.03, multivariate analysis). CONCLUSIONS: The lymphoid infiltrate is beneficial in undifferentiated NPC, and its presence may deter regional metastasis of cancer cells to the cervical nodes.

Proliferative potential in nasopharyngeal carcinoma: correlations with metallothionein expression and tissue zinc levels.

Metallothionein (MT) is a cysteine-rich protein with pleiotropic functions and a high binding affinity for heavy metals. The present study was designed to examine the relationship between MT expression and tissue zinc levels in conjunction with cell proliferation in nasopharyngeal cancer (NPC). Proliferative activity in NPC was quantified by Ki67 immunolabelling and MT expression was determined by immunohistochemistry. Total zinc and subcellular zinc fractions were analysed by flame atomic absorption spectrometry. MT immunostaining was observed in the nuclei of NPC cells, with the percentage MT immunopositivity ranging from 3.0 to 59.7%. Thirteen tumours displayed weak MT staining and the remaining 11 showed moderate to strong immunostaining. There was a significant positive correlation between MT and Ki67 positivity (P = 0.0127). Tissue zinc levels were higher in NPC as compared with benign nasopharyngeal tissues (4.800 +/- 0.4610 versus 2.889 +/- 0.4045 microgram/g dry wt tissue, respectively; P = 0.0122). Nuclear zinc levels in NPC were significantly higher than levels in membrane and cytosolic fractions (mean zinc levels 1.4840 +/- 0.1489, 0.6286 +/- 0.0789 and 0.3014 +/- 0.0250 microgram/mg protein, respectively). A linear relationship was also observed between nuclear zinc levels and MT immunostaining (P = 0.0024) as well as with Ki67 immunopositivity (P = 0.0123). Our results show that MT and zinc are correlated with proliferative activity in NPC, providing further insights into the biology of this enigmatic and aggressive tumour.

Infiltrating lymphocytes in undifferentiated nasopharyngeal cancer lack metallothionein expression.

Metallothionein (MT) is a metal-binding protein with functional roles in cell growth, repair and differentiation. MT is reported to be differentially expressed in lymphocytes of malignant gastrointestinal lesions. The level of MT protein was examined by immunohistochemical analysis at light microscopic and ultrastructural level in infiltrating lymphocytes from 20 cases of undifferentiated nasopharyngeal carcinoma (NPC). MT expression was found to be absent in the infiltrating lymphocytes of NPC and in reactive lymphocytes of lymphoid hyperplasia in nasopharyngeal tissues. Ultrastructural examination confirmed the absence of MT immunoreactivity in the lymphoid infiltrate of NPC. On the other hand, malignant lymphoblasts of diffuse large cell lymphoma, showed MT-immunopositivity by immunoelectron microscopy. This study demonstrates a lack of MT expression in the lymphoid stroma of undifferentiated NPC, a further characteristic of its non-neoplastic nature.

Correlation of metallothionein expression with apoptosis in nasopharyngeal carcinoma.

The expression of metallothionein (MT), an intracellular ubiquitous low molecular weight protein thiol with antioxidant properties, was studied in nasopharyngeal cancer (NPC) and correlated with the apoptotic index. Immunohistochemical staining of randomly selected, formalin-fixed and paraffin-embedded normal and malignant nasopharyngeal tissues were analysed for the expression of MT using the commercially available E9 antibody directed against MT I and MT II isoforms. The corresponding apoptosis labelling indices were evaluated by the TUNEL method. Localization of MT at the ultrastructural level was studied by immunogold labelling. All the tumour sections (17 specimens) showed MT-immunopositivity. A direct correlation between the percentage of MT-positive cells and the staining intensity was noted (P < 0.001; Pearson's r = 0.95). There was absence of cytoplasmic staining and only nuclear staining (with localization in the nucleoplasm) was demonstrated in the tumour cells. In normal epithelium of the nasopharynx, the basal layer was stained. An inverse relationship was observed between the level of MT expression and the apoptotic index in the NPC tissues (P = 0.0059; Pearson's r = -0.6380). The results suggest that overexpression of MT in NPC may protect the tumour cells from entering into the apoptotic process and thereby contribute to tumour expansion. Preferential localization of MT in the nuclei of NPC cells may possibly enhance radioresistance since radiotherapy is known to eradicate tumour cells by free radical-induced apoptosis.

Penetrating oesophageal foreign bodies in the thyroid gland.

Oesophageal penetration and migration of oesophageal foreign bodies into the thyroid gland is extremely rare with only occasional case reports appearing in the medical literature over the years. This is a retrospective review of four patients who were managed for penetrating oesophageal foreign bodies in the thyroid gland over an 11-year period. The clinical, radiological and intra-operative findings of the four cases are discussed.

An unusual case of sorethroat: nasopharyngeal melioidosis.

A 14-year-old Chinese female presented with severe sorethroat and swinging fever for two weeks despite one course of oral amoxycillin followed by one course of Unasyn (combination of sultamicillin, sulbactam and ampicillin). Throat swab grew Pseudomonas pseudomallel. Serology for its antibodies was very strongly positive (> 1:512). In this part of the world the IHA titre of 1:16 or greater is significant. She was successfully treated with intravenous ceftazidime. The swinging fever settled within two days. The nasopharyngeal and oropharyngeal lesions cleared after a week of therapy. A further two weeks of Ceftazidime were given to ensure a complete resolution of the infection. Oral tetracycline was given for maintenance therapy. Melioidosis involving various organs have been reported particularly pulmonary melioidosis. Nasopharyngeal melioidosis has not been reported, as far as we know. This is the first reported case.

Radiological features in a patient with Kimura's disease.

Kimura's disease is an immune mediated inflammatory disorder that usually involves the head and neck region, primarily affecting the salivary glands, adjacent muscle and regional lymph nodes. Peripheral blood eosinophilia is the norm. Clinically and radiologically, it is difficult to differentiate Kimura's disease from salivary gland malignancy, lymphoma or haemangioma. The radiological findings of a patient who presented with a left facial mass involving the left parotid gland and the adjacent muscles are discussed. We also propose that the difference in the degree of enhancement between the initial and subsequent computed tomography study done two and a half years later may be due to the development of increased fibrosis and sclerosis as the disease progresses.

Results from tattooing port-wine hemangiomas. A long-term follow-up.

Nineteen patients who had completed their course of dermatattoo treatment for the camouflage of port-wine hemangioma were evaluated at an average of 3.1 years following completion of treatment. A panel of 7 people evaluated preoperative and postoperative photographs and judged that none of the patients were more than "50 percent improved" in the camouflaging of their hemangioma, and that most of them (15 out of 19) were either "not improved" or "25 percent improved," as compared to their original photographs. We cannot rule out the possibility that this treatment may be effective in adults, as all of our patients at the time of their first treatment were between the ages of 4 and 20 years; and most of them were between 6 and 10 years old. On the basis of this evaluation, we no longer recommend the technique of dermatattoo for camouflage of port-wine hemangioma in patients in the younger age group.