Biomedical subjects
Publications and source records attributed to A Chakrabarty.
Metastatic tumours are the most common type of tumours in the spine of which only 10% occur in the cervical spine. We report a rare presentation of metastatic pheochromocytoma of the cervical spine which was successfully treated operatively. Adequate precautions should be taken during surgery as the tumour is very vascular. Radiotherapy is useful in the treatment of residual tumour.
The unusual presentation of Gorham's disease of skull base and cervical spine in a two-year-old female child with radiological signs mimicking those of raised intracranial pressure is discussed. The differential diagnosis consists of skull base tumours, meningitis, osteomyelitis of the base of skull, congenital hydrocephalaus and congenital syndromes involving the skull base. Pathologically it can be very difficult to differentiate it from lymphangioma of the bone. Difficulty in establishing the diagnosis is discussed along with failure of radiotherapy and palmidronate therapy to cause arrest of the disease process and failure of surgery to provide stabilisation. We describe the course of the disease in this child over the period of last eight years. To the best of our knowledge this is the youngest case of Gorham's described so far.
Primary presentation of an intradural Non-Hodgkin's lymphoma is rare. Recently these B cell lymphomas of mucosa associated lymphoid tissue (MALT) have gained acceptance as an important pathological subtype and are distinguishable from other primary CNS lymphomas that exhibit aggressive behaviour. Over the past decade a number of these lesions have been reported to resemble a meningioma both intra-operatively and radiologically. The authors outline such a case of marginal zone B cell lymphoma that clinically and radiologically resembled a meningioma. This case illustrates the rare occurrence of low grade dural B cell lymphoma and the need to consider this entity in the differential diagnosis of CNS lesions, if appropriate targeted therapy is to be administered.
A 72-year-old woman previously operated for a sphenoid-ridge meningioma, now presented with double vision. Histology showed a secretory meningioma with an epithelial-appearing, malignant component. Malignant transformation in a secretory meningioma is not known. This is the first report of such an occurrence.
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BACKGROUND/AIMS: To evaluate the need for routine histopathological analysis of enucleated/eviscerated eyes and changes in indications for eye removal. METHODS: Retrospective review of all enucleation/evisceration histopathology reports over 20 years. Clinical history was correlated with pathological findings. Two 10 year periods (1984-93, 1994-2003) were compared to detect changes in indications for eye removal. RESULTS: In total, 285 histopathology results were traced from 1984 to 2003; 161 and 124 were evisceration and enucleation specimens, respectively. Glaucoma, malignant melanoma, trauma, and retinal detachment were the most frequent diagnoses 1984-1993. Ocular trauma was the most frequent diagnosis 1994-2003, followed by phthisis bulbi and endophthalmitis. Three cases were diagnosed as metastatic carcinoma; all were suspected preoperatively. A fourth case was a diagnostic surprise: adenocarcinoma found in an eye removed for pain and phthisis. Comparison of two 10 year periods showed a decrease in the number of enucleations/eviscerations, perhaps reflecting a decrease in the number of specimens sent. A preference for eviscerations was evident over the 20 years. CONCLUSION: The number of eyes removed and histologically analysed decreased in the period 1994 to 2003, perhaps because of better treatment options, allowing globe preservation. There was a significant shift in the diagnosis in the two time periods, and a preference for evisceration in both. Only one diagnostic surprise was discovered (0.35%). This study does not support the need to send all globes/contents for histopathological examination. However, because of the one unexpected finding, it is recommended where the examination is incomplete or the history of visual loss is unclear.
BACKGROUND: Surgical excision of periocular skin cancer allows for optimum control in terms of tumour recurrence. Although Mohs' technique gives the best outcome, it is not widely available. Processing paraffin sections is slower but histologically superior to Mohs' frozen sections. We report the results of using a standard paraffin section (non-Mohs') technique to confirm histological clearance. METHOD: A retrospective study between 1/6/95 and 1/6/99 of all consecutive patients who had excision of periocular cancer was performed. All patients had surgical excision of the tumour with a 3-mm margin. Rapid (24-hour) paraffin sections were done and reconstruction performed if histological clearance was confirmed. If tumour was still present, a further 3-mm margin was excised at the appropriate edge(s) before reconstruction took place. RESULTS: This study yielded 93 basal cell carcinomas (BCCs) of which 86 were of primary origin and 7 were recurrent tumours. The tumour characteristics were as follows: 88% nodular BCCs, 82% had a maximum surface measurement less than or equal to 10 mm, 39.8% were inner canthal and 49.5% were localised to the lower lid. In the 30 (35.4%) cases that required further excision based on the initial histological reports, tumour was seen in only four (11.4%) cases. Overall histological clearance for primary BCCs was achieved in 81/86 (94.2%) cases. There was only one late recurrence at 4 years and 5 months. Among recurrent BCCs, there was one recurrence (12.5%) and this was despite histological clearance having been reported. CONCLUSION: For primary BCCs the recurrence rate in this study was low and comparable to that following Mohs' technique. This approach, using routine pathological facilities, therefore offers a viable technique for managing periocular BCCs.
The Herpesviridae family (Types 1-8) continues to inflict considerable morbidity and social stigma upon humanity. Once infected with the herpes viruses, especially Types 1-3, they establish permanent residence within our nervous system and reactivate during periods of stress, trauma, and/or other precipitating factors. To date, there is no cure for herpes viral infections but antivirals can attenuate the symptoms and duration of episodic outbreaks. Prophylactic therapy can suppress recurrences. The first antiviral with selective activity against virus-infected cells is considered to be acyclovir. Our article will highlight the clinical indications of the current generation, valacyclovir, which is a prodrug of acyclovir. We consider valacyclovir as a second-generation antiviral, having taken into account the initial selectivity and safety profile of its progenitor, acyclovir.
The usefulness of proliferation marker MIB1 in predicting recurrences in cranial meningiomas when other clinical and pathological factors are considered was assessed. Data from 65 patients with meningiomas were analysed and their clinical notes reviewed to define the Simpson grade of surgical excision, the location of tumour, amongst other clinical factors. The diagnosis was reviewed; immunohistochemical staining for a proliferation marker MIB1 was carried out on archival formalin-fixed, paraffin-embedded tumour and a labelling index for MIB1 (MIB1 L1) calculated. Analysis was undertaken of the impact of histology, grade of excision, tumour location and proliferation index on the risk of recurrence. The grade of surgical resection and histology type were the most important factors likely to predict recurrence. MIB1 LI was not considered useful in predicting tumour recurrence.
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The expression of heme oxygenase-1 (HO-1) is increased in the CNS of mice and rats with experimental allergic encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). To investigate the role of HO-1 in EAE, a putative inhibitor [tin-protoporphyrin IX (Sn-PP IX)] of HO-1 was administered to SJL mice during active disease. Sn-PP IX (200 micromol/kg) attenuated clinical scores, weight loss, and some signs of pathology in comparison to vehicle treatment. Glutathione levels were greater in treated EAE mice than in those receiving vehicle, indicating lower oxidative stress in the former group. These data suggest that inhibition of HO-1 attenuated disease and suppressed free radical production. In the SJL model of EAE, extravasated blood is present in the CNS, and iron released by HO-1 from this heme source may not be adequately sequestered by ferritin, allowing for iron-mediated tissue damage. Thus, HO-1 may act to amplify the disease process in this model.
Experimental allergic encephalomyelitis (EAE) is an autoimmune disease characterized by demyelination and inflammatory infiltrates in the CNS, and it is an animal model of multiple sclerosis. Piperonyl butoxide (PBO) suppresses disease in EAE mice, and it exhibits a dual effect on cytochrome P450s that manifests in a transient inhibitory phase followed by induction. In order to identify the expression of proteins associated with EAE, a proteomic screening was performed on hindbrain microsomes from control + vehicle, control + PBO, EAE + vehicle, and EAE + PBO female mice. Glucose regulated protein 94 (Grp94) and coagulation factor VIII were among the proteins identified in EAE + vehicle and EAE + PBO mice. Immunohistochemical staining of Grp94 was present in some neurons and oligodendrocytes in hindbrain sections from control animals, and in some cells within inflammatory infiltrates in EAE animals. Since Grp94 (also known as Gp96) can partake in antigen presentation and induction of proinflammatory cytokine expression, its presence in these cells suggests that it may play a role in the pathogenesis of EAE. Coagulation factor VIII is carried and protected by von Willebrand factor. Immunohistochemical staining of von Willebrand factor revealed its presence in some vessels within hindbrain sections from control animals. In EAE animals, the number of labeled vessels was significantly increased, and extracellular granular deposits were observed around labeled vessels indicating that the breakdown of the blood-brain barrier that occurs in EAE permitted its extravasation into the CNS. Additional proteins were identified in the different groups of mice by proteomic screening, but confirmation of their expression profile awaits investigations by independent measures.
Globoid cell leukodystrophy (Krabbe disease) is caused by mutations in galactosylceramidase, a lysosomal enzyme that acts to digest galactosylceramide, a glycolipid concentrated in myelin, and psychosine (galactosylsphingosine). Globoid cell leukodystrophy has been identified in many species including humans and twitcher mice. Several studies on human tissue have examined the lipid profile in this disease by gas, liquid or thin layer chromatography. Electrospray ionization tandem mass spectrometry combined with reverse phase HPLC has become a powerful alternative strategy, used here to compare the sphingolipid profile of pons/medulla tissue from twitcher mice with control tissue. In this lipidomics LC-MS approach, we scanned for precursors of m/z 264 to obtain a semi-quantitative profile of ceramides and galactosylceramides. Sphingosine-1-phosphate, C18:0 ceramide, C22:0 ceramide and C24:0 ceramide levels were reduced in the pons/medulla of twitcher mice compared to levels in control mice at 31 and 35-37 days of age. The levels of C22:0 and C24:0 galactosylceramide were similar between twitcher and control specimens and there was a trend toward reduced levels of C24:1 galactosylceramide and C24:1 hydroxy-galactosylceramide in twitcher specimens. Psychosine, C 16:0 ceramide and C 18:0 galactosylceramide levels were increased in the CNS of twitcher mice compared to levels in control mice. These data indicate that there is a trend toward decreased levels of long chain fatty acids and increased levels of shorter chain fatty acids in galactosylceramides and ceramides from twitcher mice compared with control mice, and such changes may be due to demyelination characteristic of acute pathology.
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PURPOSE: To report a case of pseudophakic endophthalmitis with secondary keratitis caused by Curvularia lunata. METHODS: A 40-year-old man presented with a fluffy mass in the anterior chamber with low-grade delayed postoperative inflammation in the right eye. RESULTS: The anterior chamber and vitreous aspirate demonstrated C. lunata. A large corneal infiltrate developed after aspiration of the mass. Treatment with systemic, topical, and intraocular antifungal agents cleared the vitreous, but the cornea perforated. CONCLUSION: Delayed low-grade infection with a fluffy mass in the anterior chamber after cataract surgery can rarely be a clinical presentation of dematiaceous fungal infection. Secondary keratitis may result after a diagnostic aspiration.
There are two reported cases of ependymomas arising in the pituitary fossa; one in a human, the other in a horse. Both died during their stay in hospital. The case presented here is the first published case of a patient who is well 3 months after surgery.
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