Optical coherence tomography in patients with a history of juvenile multiple sclerosis reveals early retinal damage.

BACKGROUND AND PURPOSE: Some 3%-10% of patients with multiple sclerosis (MS) experience disease onset before the age of 18 years ('early' onset MS, EOMS). Optical coherence tomography is a non-invasive method to measure retinal nerve fibre layer thickness (RNFLT) and total macular volume (TMV) and may be useful to differentiate axonal and neuronal damage in the retina of patients with a history of EOMS. Here RNFLT and TMV in EOMS patients after a mean disease duration of 11.6 years were compared with patients with age- or disease-duration-matched later onset MS (LOMS) and healthy controls (HCs). METHODS: In this observational cross-sectional study at two German academic MS centres, RNFLT and TMV were measured by spectral-domain optical coherence tomography in 32 HCs, 36 EOMS (mean age at onset 15.5 ± 2.0 years) and 58 LOMS patients. RESULTS: In comparison with HCs, EOMS patients displayed a significant reduction of RNFLT and TMV independently of a history of optic neuritis. In particular, RNFLT loss in EOMS was similar to that in LOMS and TMV loss was slightly higher compared with disease-duration-matched LOMS. In a generalized estimating model, the EOMS group also displayed a similar correlation between disease duration and RNFLT or TMV loss to LOMS patients. CONCLUSIONS: These data argue for a significant amount of axonal and neuronal damage in the retina of EOMS patients and may provide a structural basis for the observation that EOMS patients reach states of irreversible disability at a younger age than patients with LOMS.

Bicarbonate exporting transporters in the ovine ruminal epithelium.

In order to stabilize the intraruminal pH, bicarbonate secretion by the ruminal epithelium seems to be an important prerequisite. The present study therefore focussed on the characterization of bicarbonate exporting systems in ruminal epithelial cells. Intracellular pH (pH(i)) was measured spectrofluorometrically in primary cultured ruminal epithelial cells loaded with the pH-sensitive fluorescent dye, 2,7-bis(carboxyethyl)-5(6')-carboxyfluorescein acetomethyl ester. Switching from CO2/HCO3- -buffered to HEPES-buffered solution caused a rapid intracellular alkalinization followed by a counter-regulation towards initial pH(i). The recovery of pH(i) was dependent upon extracellular chloride, but independent of extracellular sodium. Adding 500 microM H2DIDS significantly reduced the increase of pH(i). For further characterization of the bicarbonate exporting systems, we tested the ability to reverse the direction from HCO3- export to import in the absence of sodium and chloride. Under sodium and chloride-free conditions, counter-regulation after CO2-induced pH(i) decrease did not differ from pH(i) recovery in the presence of sodium and chloride. Existence of bicarbonate exporting systems in cultured ruminal epithelial cells and intact ruminal epithelium was verified by reverse transcription polymerase chain reaction (RT-PCR). Using RT-PCR and subsequent sequencing, expression of mRNA encoding for AE2, DRA and PAT1 could be found. Bicarbonate exporting systems could therefore be detected both on the functional and structural level.

Molecular and functional evidence for a Na(+)-HCO3(-)-cotransporter in sheep ruminal epithelium.

The present study aimed to identify the HCO3(-)-dependent mechanisms contributing to the homeostasis of the intracellular pH (pHi) in ruminal epithelial cells of sheep. Therefore, pHi was measured spectrofluorometrically in primary cultured ruminal epithelial cells loaded with the pH-sensitive fluorescent dye, 2',7'-bis(carboxyethyl)-5(6')-carboxyfluorescein acetoxymethyl ester. Switching from a HEPES-buffered to a CO2/HCO3(-)-buffered solution caused a rapid intracellular acidification followed by a counter-regulation towards alkaline levels. The counter-regulation was totally dependent upon extracellular Na+, but independent of intracellular Cl-. Adding 30 microM EIPA to the solutions did not affect the pHi counter-regulation following the acidification. Presence of 500 M H2DIDS inhibited the counter-regulation of pHi by 67%. These results pointed to a Na(+)-HCO3(-)-cotransporter (NBC) as the main pHi regulatory mechanism in the presence of HCO3-. Existence of an NBC in both cultured ruminal epithelial cells and intact ruminal epithelium was verified by reverse transcription polymerase chain reaction (RT-PCR) studies. RT-PCR yielded a band of the expected molecular size of 333 bp in both cultured cells and intact epithelium. The mRNA sequences were identical and shared a homology of 62% with human kidney NBC (Genebank accession number AF007216), of 66% with rat kidney NBC (AF004017) and of 65% with mouse duodenal NBC (AF141934).

Calciphylaxis in a patient without renal failure or elevated parathyroid hormone: possible aetiological role of chemotherapy.

Calciphylaxis is a rare, often fatal disease characterized clinically by progressive cutaneous necrosis and ulceration, and histologically by vascular calcification and thrombosis. It has been described in association with end-stage renal disease, after initiation of dialysis, following renal transplantation, and in patients with hyperparathyroidism. We present the first case of calciphylaxis occurring in a patient with both normal renal function and parathyroid hormone level and discuss the possible aetiological role of chemotherapy-induced functional protein C and protein S deficiency.

The Xiphophorus-derived antibody, XMEL, shows sensitivity and specificity for human cutaneous melanoma but is not a prognostic marker.

XMEL is a monoclonal antibody raised against part of the extracellular domain of the putative tyrosine kinase receptor protein implicated in the pathogenesis of melanoma formation in the Xiphophorus fish melanoma model. Our objective in this study was to determine the diagnostic and prognostic utility of XMEL for human melanoma. Formalin-fixed tissue from 82 melanomas, 42 carcinomas, 23 neural tumors, 12 lymphomas and 12 sarcomas were immunostained with XMEL and compared with a widely used melanoma antibody, HMB-45. The sensitivity of HMB-45 (83.1%) was similar to that of XMEL (79.8%). XMEL detected 7 melanomas that were HMB-45 negative. Specificity for detection of melanoma was greater with HMB-45 (95.5%) as compared to XMEL (80.9%). Of interest, all 4 prostatic adenocarcinomas were XMEL positive. These data suggest that XMEL is as sensitive but not as specific as HMB-45 in the detection of cutaneous melanoma but may serve as an ancillary antibody to improve diagnostic yield. The consistent positivity of XMEL in melanoma lends support to the hypothesis that the detected protein plays a role in melanoma pathogenesis. XMEL reactivity is not an independent prognosticator of death from melanoma in 37 melanomas from patients with at least 10 years' follow-up. These data and the fact that XMEL shows variable reactivity with metastatic melanomas but almost 100% reactivity with the primary melanomas suggest that the antigen recognized by the XMEL antibody may be important in the early stages of melanoma progression. This is supported by our earlier observation that XMEL is reactive with dysplastic nevi, a precursor of malignant melanoma.

Neutrophilic spongiosis in pemphigus herpetiformis.

Pemphigus herpetiformis is a rare pemphigus variant with light microscopic features that have historically been described as either "acantholytic dermatitis herpetiformis" or as "eosinophilic spongiosis in pemphigus". The clinical features of this form of pemphigus are reminiscent of dermatitis herpetiformis; however, the direct immunofluorescence finding of epidermal inter-cellular IgG deposition is that of the pemphigus group. We report two patients with clinical presentations suggestive of dermatitis herpetiformis in whom the histopathologic features were those of a neutrophilic intraepidermal blistering disorder. Biopsies showed marked epidermal spongiosis with midepidermal acantholytic vesicles containing predominantly neutrophils and a few eosinophils. Direct immunofluorescence was positive for epidermal intercellular IgG; IgA deposition was not present. Neutrophilic spongiosis, in the absence of a prominent eosinophilic infiltrate, should be recognized as an early finding in some cases of pemphigus, and immunofluorescence studies are justified when this histologic feature is encountered in a skin biopsy.

Cytometric analysis of ventricular myocyte nuclei in idiopathic dilated cardiomyopathy: a tool for evaluation of disease progression?

The progression of idiopathic dilated cardiomyopathy (IDC) is governed by factors that remain obscure. The disease pathway toward cell degeneration or death results in irreversible myocyte change including nuclear cytometric alterations which may be evaluable and ultimately correlated with other measures of disease evolution. Using a novel image cytometry system, we analysed differences in ventricular myocyte nuclear morphology and DNA content and distribution in right and left ventricular free wall myocardium and in ventricular septal myocardium from 11 normal and 13 IDC human autopsy hearts. Nine morphological features of IDC myocyte nuclei differed significantly (P < 0.001) from normal. These were used to establish a classification matrix and cytometry-based assessment and allowed correct categorization of left and right ventricular and ventricular septal myocyte nuclei in concordance with their respective pathological diagnosis (i.e. normal or IDC) 71%, 81% and 77% of the time. Additionally, four photometric features were significantly different (P < 0.005) in IDC versus normal hearts, as were three discrete texture features (P < 0.001). Thus, the spectrum of myocyte nuclei seen in IDC have highly characteristic and measurable morphologic, photometric and texture features. Our findings indicate the potential value of cytometry in the classification of myocytes with regards to a disease continuum and suggest its applicability in both clinical and experimental studies.

Critical clue to ethylene glycol poisoning.

The authors report the case of a man 49 years of age with near-fatal ethylene glycol poisoning. Detection of calcium oxalate monohydrate crystals in the urine was the only real-time confirmation of the diagnosis. The case illustrates that, if the toxin has already been metabolized, familiarity with the appearance and significance of this unusual form of calcium oxalate crystal may be the key to an accurate diagnosis.