Subretinal fluid is common in experimental non-arteritic anterior ischemic optic neuropathy.

PURPOSE: Anterior ischemic optic neuropathy (AION) is an important cause of acute vision loss for which several animal models exist. It has been associated with subretinal fluid in a previous study on patients but not yet so in animal models. PATIENTS AND METHODS: A patient presented with acute non-arteritic AION (NAION) and underwent ophthalmic evaluation and testing including fluorescein angiography and spectral-domain optical coherence tomography (SD-OCT). On the basis of the patient's findings, we used SD-OCT circular and volume scans to analyze retinal changes in a murine model of NAION. RESULTS: One week after left eye vision loss, the patient had clinical and imaging findings consistent with NAION. On SD-OCT, there was prominent peripapillary retinal thickening consistent with intra-retinal edema and sub-foveolar fluid. Inspired by the findings in human AION, we looked for similar changes in murine NAION using SD-OCT. The circular scan did not adequately detect the presence of subretinal fluid. Using the 25-line scan, which covered a larger part of the posterior pole, we found that 100% of murine AION resulted in subretinal fluid at day 1. The subretinal fluid resolved by week 1. CONCLUSION: This study detailed a case of clinical NAION associated with intra-retinal and subretinal fluid. We also found that subretinal fluid was common in murine photochemical thrombosis model of AION and could be found far away from the optic disc.

A rare combination of recurrent pneumonia, diarrhoea, and visual loss in a patient after thymectomy: good syndrome.

This report describes a 68-year-old Chinese man who was diagnosed with Good syndrome 6 years after initial presentation when he underwent thymectomy. He presented with recurrent pneumonia, diarrhoea, weight loss, and visual symptoms. Extensive examination for anaemia and neutropenia was done, yet no conclusive diagnosis could be derived. During his last admission for pneumonia, his history of AB thymoma suggested the possibility of Good syndrome. Immunological testing revealed low T cells, absent B cells, and low immunoglobulin M and immunoglobulin G levels. Moreover, he had histologically identified cytomegalovirus pneumonia, cytomegalovirus colitis, and fundoscopic features of cytomegalovirus retinitis. He was treated with a 2-week course of intravenous ganciclovir, lifelong oral valganciclovir, and monthly immunoglobulin infusion. It took 6 years for the diagnosis to be established, therefore, early attention and vigorous search for such potentially treatable conditions in post-thymectomy patients presenting with recurrent infections is recommended.

Review of children hospitalised for ingestion and poisoning at a tertiary centre.

INTRODUCTION: The main aim of this study is to determine the pattern of referrals of poisoning to a tertiary university hospital. The information will be used for poison prevention programme planning, and for educating and awareness promoting to the public. MATERIALS AND METHODS: All patients (under 21 years of age) admitted to the paediatric wards between January 1997 and December 2002 with a discharge diagnosis indicating unintentional (UP) or intentional poisoning (IP) were identified through the computerised discharge information. RESULTS: Sixty males and 98 females accounted for 161 admissions over the 6-year period. Their mean (standard deviation, SD) age was 8.2 (6.2) years. Sixty per cent of admissions involved UP. Females accounted for 47% of the UP but 86% of the IP [odds ratio of females for IP, 7.05; 95% confidence interval (CI) 2.95 to 17.28]. When compared with UP, IP patients were significantly older [mean (SD): 14.9 (1.7) versus 3.6 (3.3) years]. In 70% of the admissions, the patients ingested a single substance. Tablets and pills, especially in the IP adolescents, were more commonly ingested than syrups. The spectrum of substances ingested was vast but paracetamol, cough or cold medicines, and common adult household medications and agents accounted for the majority of medications ingested. The substances ingested were obtained at home in 81 cases (50%) and as over-the-counter medication in 33 (20%). The majority (92%) of patients presented within 24 hours of ingestion. On admission, 63% of UP and 45% of the IP were asymptomatic. No active treatment was required in 65% of patients. In IP, nearly 30% of IP who ingested paracetamol had toxic levels and received N-acteyl cysteine. A history of previous poisoning was more common and subsequent follow-up was offered to 74%. CONCLUSION: Young boys were more at risk of unintentional ingestion whereas adolescent girls were more likely to ingest medications as a gesture of suicide. Paracetamol is a frequently ingested medicinal for which an antidote is available.

Growth inhibitory activity of lemnabourside on human prostate cancer cells.

Induction of apoptosis and androgen ablation are two major approaches for treating human prostate carcinoma. In a study of the bioactive components of the soft coral Nephthea chabroli, we found that lemnabourside is a 5alpha-reductase inhibitor, as shown by its ability to inhibit the conversion of testosterone into the more potent dihydrotestosterone in rat prostate homogenate. The compound also inhibited the incorporation of tritiated thymidine into human prostate androgen-dependent carcinoma LNCaP cells, and thus blocking the cell proliferation (IC50 = 37.5 microM). The expression of prostate marker genes, including 5alpha-reductase, prostate-specific antigen, prostatic acid phosphatase and androgen receptor, and the anti-apoptotic bcl-2 gene were markedly reduced, but the transcription of apoptosis-related caspase 3 gene showed a dose-dependent increase in lemnabourside-treated LNCaP cells. Immunofluorescent microscopy and flow cytometric analysis further demonstrated apoptotic changes in these cells. Taken all results together, a relatively weak 5alpha-reductase inhibitory activity on LNCaP cells (EC50 > 250 microM), and a similar growth inhibitory activity on both androgen dependent- and independent-prostate cells (IC50 approximately 37.5 microM) indicated that caspase-3 apoptosis pathway is one of the possible antiproliferative activities mediated by lemnabourside.

Relaxant actions of nonprostanoid prostacyclin mimetics on human pulmonary artery.

The specific prostacyclin (IP) receptor agonist cicaprost relaxed human pulmonary artery preparations precontracted with phenylephrine [50% inhibitory concentration (IC50) approximately 0.6 nM], U-46619 (IC50 approximately 0.9 nM), and K+ (approximately 40% maximal relaxation); endothelium removal had little effect on relaxant activity. Ranking of relaxant potencies for prostacyclin and five of its analogs was 17 alpha, 20-dimethyl-delta 6,6a-6a-carba PGI1 (TEI-9063) > or = cicaprost > iloprost > prostacyclin > taprostene > benzodioxane prostacyclin > 15-deoxy-16 alpha-hydroxy-16 beta,20-dimethyl-delta 6,6a-6a-carba PGI1 (TEI-3356). The potency of the isocarbacyclin TEI-3356 may have been under-estimated because of its contractile (EP3 receptor agonist) activity. The potency ranking of four nonprostanoid prostacyclin mimetics was 3-[4-(4,5-diphenyl-2-oxazolyl)-5-oxazolyl]phenoxy] acetic acid (BMY 45778; IC50 approximately 2.5 nM) > > 2-[3-[2-(4, 5-diphenyl-2-oxazolyl)ethyl]phenoxy]acetic acid (BMY 42393) > octimibate > CU 23 (a novel diphenylindole). From IP receptor binding affinities obtained on human platelet membranes, it is suggested that the slightly shallower log concentration-response curves for BMY 45778, BMY 42393, and CU 23 may reflect the near-maximal receptor occupancy required for complete relaxation. A fifth nonprostanoid, CU 602, had much shallower log concentration-response curves than cicaprost against phenylephrine tone but not against U-46619 tone; this may indicate IP receptor partial agonism coupled with TP receptor antagonism. The relaxant actions of the nonprostanoid mimetics were more persistent than those of the prostacyclin analogs on washout of the organ bath; by the inhalation route, this type of compound may be retained within pulmonary tissue and thus afford greater pulmonary/systemic selectivity than currently used pulmonary vasodilators.

Benign giant cell tumor of bone with osteosarcomatous transformation ("dedifferentiated" primary malignant GCT): report of two cases.

It is not uncommon for sarcomatous transformation of giant cell tumor (GCT) of bone to occur after radiation, but rarely does malignant transformation occur spontaneously, with less than 15 cases reported up to 1995. Only four of these cases have been documented in detail. We report two additional cases of GCT of bone spontaneously transforming or "dedifferentiating" into osteosarcoma without radiation therapy. The first case is absolutely unique and most interesting in that the dedifferentiation process occurred in one of multiple GCT lung metastases 6 years after successful eradication of a primary tibial tumor. The right lung was resected due to development of a large tumor, and at pathologic examination, demonstrated several small nodules of conventional GCT and a much larger, 14-cm mass composed of a mixture of GCT and high-grade osteosarcoma. The second case involved a physician, who had a large tumor in the sacrum with vague symptoms for 8 years. Open biopsy revealed conventional, benign GCT of bone with a secondary aneurysmal bone cyst. Complete curettage 2 weeks later revealed, in addition to areas of conventional, benign GCT a second component of very high grade osteosarcoma. Both patients died less than 1.5 years from diagnosis. This report of osteosarcomatous transformation of a conventional GCT of bone strengthens the theory that there is a mesenchymal cell line in GCT that may spontaneously transform to sarcoma.

Thoracoscopic talc insufflation versus talc slurry for symptomatic malignant pleural effusion.

BACKGROUND: Talc has been generally accepted to be the most effective sclerosant for chemical pleurodesis, although the optimal route of administration remains unclear. METHODS: We designed a prospective, randomized study to compare video-assisted thoracoscopic talc insufflation with bedside talc slurry in the treatment of malignant pleural effusion. From September 1993 to November 1995, 57 patients were recruited and randomized to either video-assisted thoracoscopic talc insufflation under general anesthesia (n = 28) or talc slurry by the bedside (n = 29). Patients with poor general condition (Karnofsky score less than 30%), poor pulmonary function (forced expiratory volume in 1 second less than 0.5 L), or trapped lungs were excluded from this study. Five grams of purified talc was used for either video-assisted thoracoscopic talc insufflation or talc slurry. RESULTS: There was no statistically significant difference between the two groups of patients with respect to age, sex ratio, chest drainage duration, postprocedural hospital stay, parenteral narcotics requirement, complications, or procedure failure (ie, recurrence). CONCLUSIONS: Video-assisted thoracoscopic talc insufflation has not been shown to be a superior approach compared with talc slurry in our study. Because the former demands more resources, we advocate that talc slurry should be considered as the procedure of choice in the treatment of symptomatic malignant pleural effusion in patients who do not have trapped lungs.

A case report of a large thymic carcinoid.

Thymic carcinoid is a rare tumour. A case of giant thymic carcinoid with extensive necrosis is reported in a 44-year-old Chinese male. Diagnosis was difficult to make before the operation and even intraoperatively. Subtotal excision was performed followed by adjuvant radiation therapy. The patient remained disease-free at the last follow-up 12 months after surgery. Complete excision remains the mainstay of treatment for this disease.

The use of liver grafts infested with Clonorchis sinensis for orthotopic liver transplantation.

In the Orient, millions are known to have Clonorchis sinensis (biliary trematodiasis) infestation. When these infested livers become available as donor organs, there are potentially serious implications that the transplant team would need to consider. We report the use of two such infested livers, one from a cadaveric donor and the other from a live related donor, for orthotopic liver transplantation. The parasite was encountered not only during organ procurement, but also caused early postoperative blockage of the hepatico-jejunostomy splintage tube and cessation of bile flow in the second recipient. Upon follow-up for four and two years, respectively, no other ill effect has been observed in either patient. Repeated examination of stool for ova of C sinensis in both patients during follow-up visits had been negative, indicating that all the parasites probably had been killed by the cold perfusion. In view of the severe shortage of liver grafts and the lack of serious morbidity associated with the use of these infested livers, we have adopted the policy to include these livers for future transplantation. Special considerations and precautions are, however, required during the perioperative period and on long-term follow-up.

Video assisted thoracoscopic staple resection of a giant bulla.

Video assisted thoracoscopic surgery (VATS) for spontaneous pneumothorax has been well described. However, there are few reports on the use of this technique on giant bullae. We report a 49 year old man with a symptomatic giant bulla who underwent a successful thoracoscopic staple resection. His chest drains were removed on the second postoperative day and he was discharged on the third postoperative day with virtually no discomfort. We conclude that thoracoscopic staple resection of a giant bulla is feasible technically and is an attractive alternative to the conventional open technique.

Immature mediastinal teratoma in a 2 1/2 year old Chinese girl.

Teratoma is a rare tumour in children accounting for about 3% of all childhood malignancy. A case of immature mediastinal teratoma in a young Chinese girl is reported.

Thoracoscopic management of malignant pleural effusions.

Malignant pleural effusion is a common condition and often presents a challenge for treatment. We report our experience from a single institution with the use of video-assisted thoracoscopic surgery (VATS) in the management of malignant effusions. From September 1992 to April 1995, 69 patients (31 men, 38 women; age range, 38 to 76 years) underwent diagnosis and/or treatment of malignant effusions; these included 46 pleural biopsies, 34 talc insufflations, and 16 limited decortications. There was no mortality and there were no intraoperative complications. Postoperative complications occurred in seven patients (10%). Specific histologic diagnoses were obtained in all but 6 patients (87%). Malignant effusion was confirmed in 25 of 46 cases (54%). Thoracoscopic talc insufflation with or without additional decortication was successful in 32 of 34 cases (94%) in controlling recurrence of effusion after a mean follow-up of 6 months among the survivors (22 patients died during the follow-up period without effusion reaccumulation). We conclude that VATS not only provides an accurate diagnosis but also allows effective therapeutic procedures to be performed for malignant effusions that are associated with an acceptable morbidity.

Thoracoscopic lobectomy for an infected intrapulmonary bronchogenic cyst.

A 19-year-old male who presented with cough and fever was found to have an 8-cm cyst in his left lung. Video-assisted thoracoscopic left lower lobectomy was performed. The cyst had to be decompressed by needle aspiration prior to retrieval through a 5-cm minithoracotomy. The patient was discharged on postoperative day 4 in good condition. The technical aspects form the basis of this report.

Video-assisted thoracoscopic anatomic lung resections. The initial Hong Kong experience.

We report our combined experience on video-assisted thoracoscopic (VAT) anatomic lung resections from two major hospitals in Hong Kong over a 17-month period. From August 1993 to December 1994, 82 cases of major lung resections were attempted using the VATS approach, of which 60 were successfully completed (55 lobectomies, 2 bilobectomies, 2 pneumonectomies, and 1 segmentectomy). Of these 60 cases, there were 43 men and 17 women with a mean age of 66 years (range, 37 to 85 years). The final pathologies were 52 primary lung cancers (37 adenocarcinoma, 11 squamous cell carcinoma, 2 bronchoalveolar carcinoma, 1 adenosquamous carcinoma, and 1 undifferentiated carcinoma); 1 pulmonary metastasis (from nasopharyngeal carcinoma); and 7 benign lesions (3 tuberculosis, 1 bronchiectasis, 1 sclerosing hemangioma, 2 organizing pneumonia). There was one postoperative death (mortality rate, 1.8%). Complications include persistent air leak over 10 days (four), wound infection (two), supraventricular tachycardia (three), and recurrence of tumor over the utility thoracotomy scar (one). All the patients were followed up from 8 weeks to 19 months (mean, 10 months). The mean duration of chest drainage was 5.4 days (range, 2 to 25 days). The mean hospital stay was 7.2 days (range, 4 to 35 days). The average postoperative parenteral narcotic (meperidine hydrochloride [Pethidine]) requirement by patient-controlled analgesia was 275 mg (range, 75 to 800 mg). This compared favorably with an age- and sex-matched historic group of patients who underwent posterolateral thoracotomy and had a hospital stay of 10.4 days (statistically non-significant) and narcotic requirement of 950 mg (statistically significant by paired t test). We conclude that VAT anatomic lung resection is technically feasible. However, there are some specific complications associated with major lung resection through minimal access. Refinement of our present technique and attention to details are important to improve our results.

Video-assisted thoracoscopic thymectomy for myasthenia gravis.

Video-assisted thoracoscopic surgery (VATS) provides a new approach to thymectomy. From June 1993 to December 1994, we performed a total of eight thymectomies for myasthenia gravis (MG). There were four male and four female patients with ages ranging from 9 to 76 years. Three of the eight patients had associated thymoma. We believe that complete thymectomy was accomplished in all cases by examination of the thymic bed and resected specimen. There was no mortality or intraoperative complications. The median postoperative hospital stay was 5 days (range, 2 to 37 days). One patient required ventilatory support postoperatively. Clinical improvement was observed in all patients after a mean follow-up of 10 months (range, 2 to 21 months). Compared with a comparable historical group of patients with MG who underwent transsternal thymectomy, the VATS group was associated with significantly less analgesic requirement and shortened hospital stay. We conclude that VAT thymectomy is technically feasible and is associated with a favorable postoperative course compared with the transsternal approach. We believe that complete thymectomy can be achieved by this approach. Further investigation with long-term follow-up is needed to further clarify the role of VAT thymectomy in thoracic surgery.

Video-assisted thoracoscopic wedge resections of pulmonary metastatic osteosarcoma: should it be performed?

We studied the use of video-assisted thoracoscopic (VAT) surgery in the management of metastatic osteosarcoma. From September 1993 to March 1994, we performed a total of 11 VAT wedge resections of pulmonary metastatic osteosarcoma in seven patients (six males, one female, age 12 to 46 years). Three patients had bilateral procedures performed either under the same anaesthesia or in stages. One patient had two operations on the same side. The average number of nodules excised was three. Two patients subsequently required formal lobectomies when the metastatic tumours were either too big or too close to the hilum for safe wedge resections. There was one death on postoperative day 3 due to dysrhythmia. One patient died 5 months later from a progression of his underlying disease. Two patients remained disease free up to 8 and 12 months, respectively, from their first operations. The average postoperative chest drain duration was 1.4 +/- 0.7 days and hospital stay 2.3 +/- 1.1 days. The procedure was well tolerated and postoperative morbidity was minimal. We conclude that although VAT wedge resection of pulmonary metastatic osteosarcoma is feasible technically and is associated with a short hospital stay and minimal morbidity, this approach cannot be recommended when complete resection of all metastases is the goal as the technique relies heavily on computed tomographic scans to detect nodules. Recurrence of metastasis from 4 to 6 months in three of seven patients argues against VAT surgery being an adequate procedure. The high cost of the staplers, in addition, is a secondary consideration.

Interactions of a very long chain fatty acid with model membranes and serum albumin. Implications for the pathogenesis of adrenoleukodystrophy.

Adrenoleukodystrophy (ALD) is an inherited disorder of fatty acid metabolism marked by accumulation of very long chain saturated fatty acids (VLCFA), especially the 26-carbon acid, hexacosanoic acid (HA), in membranes and tissues. We have studied interactions of 13C-enriched HA with model membranes (phospholipid bilayer vesicles) and bovine serum albumin (BSA) by 13C NMR spectroscopy to compare properties of HA with those of typical dietary fatty acids. In phospholipid bilayers the carboxyl group of HA is localized in the aqueous interface, with an apparent pKa (7.4) similar to other fatty acids; the acyl chain must then penetrate very deeply into the membrane. Desorption of HA from vesicles (t1+2 = 3 h) is orders of magnitude slower than shorter chain fatty acids. In mixtures of vesicles and BSA, HA partitions much more favorably to phospholipid bilayers than typical fatty acids. BSA binds a maximum of only 1 mole of HA at one binding site. Calorimetric experiments show strong perturbations of acyl chains of phospholipids by HA. We predict that disruptive effects of VLCFA on cell membrane structure and function may explain the neurological manifestations of ALD patients. These effects will be further amplified by slow desorption of VLCFA from membranes and by the ineffective binding to serum albumin.