A sequential study of visual evoked potential in patients with vitamin B12 deficiency neurological syndrome.

OBJECTIVE: Visual pathways are vulnerable to vitamin B(12) deficiency but there is paucity of studies evaluating visual evoked potential (VEP) changes following vitamin B(12) supplementation. Our aim was to evaluate the visual evoked potential changes in patients with vitamin B(12) deficiency neurological syndrome and their changes after vitamin B(12) therapy. METHODS: Seventeen patients with vitamin B(12) deficiency neurological syndromes diagnosed on the basis of megaloblastic bone marrow or low serum vitamin B(12) level or both were subjected to testing of visual acuity, field of vision, colour vision and neurological examination. Cranial magnetic resonance imaging was done in 9 patients and pattern reversal VEP was carried out on admission. P(100) latency and amplitude were measured. Visual function and VEP studies were repeated at 3 and 6 months after vitamin B(12) therapy. RESULTS: The patients' age ranged between 17 and 69 years; 7 were females and 16 were lactovegetarians. The duration of symptoms ranged between 10 days and 10 years. Visual acuity, colour vision, field of vision and fundus oculi were normal. VEP revealed prolongation of P(100) latency in 10 patients (17 eyes) which was mild in 2, moderate in 10 and marked in 5 eyes. Six months after treatment, P(100) latency improved to normal in all except 4 eyes. VEP abnormality was related to duration of illness and antiparietal cell antibodies. CONCLUSIONS: VEP is frequently prolonged in patients with vitamin B(12) deficiency neurological syndrome although asymptomatic. It usually returns to normal after treatment.     

Polymerization of vinyl monomers photoinitiated by benzoylated polystyrene

The rate of the polymerization of vinyl monomers photoinitiated (at λ = 365 nm) by benzoylated polystyrene in N,N-dimethylformamide (DMF) decreases in the sequence vinyl acetate>acrylonitrile>methyl methacrylate ? styrene ≈ 0 and is related to the rate constant of propagation of the mentioned monomers. In addition to DMF, aromatic hydrocarbons (benzene, toluene, p-xylene), cyclohexane and tetrahydrofuran were employed as hydrogen donors. The maximum polymerization rate was achieved in the system containing p-xylene; the system with benzene turned out inefficient for the initiation of acrylonitrile polymerization. Turbidimetric titration of a soluble fraction of the acrylonitrile polymerization in DMF in presence of benzoylated polystyrene showed that the soluble fraction does not contain graft copolymers of benzoylated polystyrene with acrylonitrile. It is assumed, however, that the polyacrylonitrile in the insoluble fraction is bound to benzoylated polystyrene in the form of graft copolymers.     

Evoked potential changes in ischaemic myelopathy

Somatosensory evoked potentials are employed in the intraoperative monitoring but there is paucity of information about the motor evoked potentials (MEP) in spinal cord ischaemia. Two patients aged 9 and 4 years developed paraplegia following surgery for coarctation of aorta. The aortic cross clamping time in these patients was 100 min and 30 min. respectively. The patient with longer clamping time had flaccid paraplegia and lower limb MEPs were not recordable; whereas the patient with shorter clamping time had spastic paraparesis and prolonged CMCT to right lower limb. The latter patient improved significantly. Tibial SEPs were normal in both the patients. Our results suggest that MEP may have a greater role than SEP in documenting and prognosticating ischaemic myelopathy.     

Urothelial signet-ring cell carcinoma of the renal pelvis with collagenous spherulosis: a case report

We present a unique case of urothelial carcinoma of the right renal pelvis. It occurred in a 58-year-old woman. The tumor was located in the renal pelvis with extension into the adjacent renal medulla and cortex. Two years after surgical excision the patient is free of recurrence and metastasis. The tumor was well demarcated, without capsule, firm, solid, and whitish on the cut surface. It was 3x4 cm in largest diameter and without signs of necroses and hemorrhages. The tumor did not infiltrate the ureter. Histologically the predominant pattern of the tumor was adenocarcinomatous differentiation, and only very rare foci of urothelial carcinoma composed of typical transitional cells were found. No signs of intestinal type of metaplasia and adenocarcinoma, changes similar to the cystitis cystica or cystitis glandularis, were found in the tumor or in its vicinity. Most of the tumor looked like solid nests composed of cells with intracytoplasmic lumens. The resulting appearance was that of typical signet-ring cell change. These solid nests were usually surrounded by columnar epithelium, which in many areas formed papillary structures. A very striking feature was formation of collagen spherules. Small collagen spherules were often surrounded by a layer of the neoplastic cells so that collagenous rosettes were formed. In some areas these collagenous spherules clustered together so that they formed areas of collagenous spherulosis. The collagen in the spherules reacted positively with collagen IV. Ultrastructurally these spherules were formed by basal membrane-like material. Intracytoplasmic lumens of the signet-ring cell change were endowed by slender microvilli at ultrastructural level.     

SPECT changes and their correlation with EEG changes in tuberculous meningitis

OBJECTIVE: In tuberculous meningitis (TBM) blood flow may be altered due to associated vasculitis, hydrocephalus and raised intracranial pressure. Electroencephalography (EEG) and single photon emission computed tomography (SPECT) provide information about electrical activity and regional cerebral blood flow respectively. This study aims at the correlation of EEG and SPECT changes in patients with TBM. METHOD: Sixteen patients with TBM whose age ranged between 5 and 62 years and 3 of whom were females were subjected to clinical, radiological (CT and/or MRI), EEG and SPECT studies using 99mTc ethylene cystine dimer (ECD). Ten patients were in stage III and 3 each in stage II and stage I meningitis. Cranial CT scan was carried out in 15 and MRI in 4 patients. Hydrocephalus was present in 9, infarction in 7 and tuberculoma in 5 patients. RESULTS: SPECT studies were abnormal in all except 2 patients revealing basal ganglionic hypoperfusion in 14 and focal cortical hypoperfusion in 9 patients. The EEG was abnormal in 11 patients which included delta slowing in 5, theta slowing in 6, frontal intermittent rhythmic delta activity (FIRDA) in 3 and epileptiform discharges in 2 patients. All the patients with abnormal EEG had abnormal SPECT study except 1. In 4 patients, EEG was normal although there was subcortical hypoperfusion on SPECT. In spite of high frequency of focal cortical hypoperfusion (9 patients), EEG revealed focal abnormality in 3 patients only. CONCLUSION: It can be concluded that the SPECT reveals more frequent abnormalities compared to EEG and CT scan. Cortical hypoperfusion with or without basal ganglia hypoperfusion is associated with FIRDA and diffuse delta slowing on EEG.     

Vitamin B12 deficiency neurological syndromes: a clinical,MRI and electrodiagnostic study

BACKGROUND: Vegetarianism is an important cause of vitamin B12 deficiency, especially in countries like India. We managed 17 patients with neurological syndrome due to vitamin B12 deficiency in a tertiary care referral teaching hospital which caters to relatively affluent population. AIM: To evaluate neurophysiological and MRI changes in patients presenting with vitamin B12 deficiency neurological syndrome and interpret these is the light of reported autopsy findings. SETTING: Tertiary care referral teaching hospital. METHODS: Patients with vitamin B12 deficiency neurological syndrome diagnosed by low serum vitamin B12 and/or megaloblastic bone marrow were subjected to clinical evaluation and spinal MRI. The neurophysiological tests included nerve conduction studies, tibial somatosensory evoked potential (SEP), motor evoked potential (MEP) and visual evoked potential (VEP) studies. The recovery was defined on the basis of 6 months Barthel Index score into complete, partial or poor. RESULTS: There were 17 patients with vitamin B12 deficiency neurological syndrome, 3 were females and 12 lactovegetarian. The clinical syndrome was that of myelopathy in 8, myeloneuropathy in 5, dementia myelopathy in 3 and neuropathy in 1 patient. All the patients had impaired joint position and vibration sensation in the lower limbs and 4 had in upper limbs as well. Lower limbs were spastic in 13 and upper limbs in 2 patients. Spinal MRI revealed T2 hyperintensity in cervicodorsal region in 6 and cord atrophy in 3 patients. Sural nerve conduction was abnormal in 8 and peroneal conduction in 5 patients. In one patient all sensory nerve conductions were unrecordable but motor conductions were normal. Tibial SEP was abnormal in 12 out of 15 and lower limb MEP in 8 out of 12 patients. P100 latency of VEP was prolonged in 7 out of 13 patients. Right to left asymmetry was present in tibial SEP in 4 and VEP in 2 patients. At 6 months followup 2 patients improved completely, 7 partially and 3 had poor recovery. Clinical recovery correlated with MEP but not with SEP or MRI changes. CONCLUSION: The evoked potential and MRI changes in vitamin B12 deficiency neurological syndrome are consistent with focal demyelination of white matter in spinal cord and optic nerve. Myelopathic presentation is commoner and SEP is more frequently abnormal. The outcome at 6 months correlated with MEP changes.     

Mixed epithelial and stromal tumors of the kidney. A report of 22 cases

Mixed epithelial and stromal tumor of the kidney (MESTK) is a recently described subset of renal neoplasm that tends to occur in middle-aged and older women and is characterized by a distinctive histological appearance. To further characterize this lesion, we report the clinicopathological and immunohistochemical features of 22 additional cases from our institutional files. Grossly, the tumors ranged in size from 1 cm to 14 cm (mean 6.7 cm), were well circumscribed but unencapsulated, and showed a cystic cut surface. The tumors were composed of a spindle cell proliferation that resembled ovarian stroma, as well as an epithelial component lining the cystic structures, which usually consisted of flat to hobnailed cells typical of collecting-duct epithelium. Areas displaying features of Müllerian differentiation were also documented in 6 cases, including epithelium of endometrioid, tubal, clear cell and squamous cell type as well as one case showing an architecture that closely resembled Müllerian adenofibroma and adenosarcoma. Follow-up in 14 patients (average 4.4 years) showed no evidence of recurrence or metastasis. We believe these tumors represent the renal counterpart of similar mixed epithelial and stromal neoplasms occurring in the biliary tract and pancreas, which is also characterized by cystic structures lined by epithelium, admixed with ovarian-type stroma. The differential diagnosis for these tumors includes cystic nephroma and cystic partially differentiated nephroblastoma, which we believe to represent clinically and morphologically distinct entities from MESTK. In particular, the distinction from cystic nephroma in adult male patients is emphasized, and two cases of this entity are included in the study for comparison.     

Krill Oil Supplementation Reduces Exacerbated Hepatic Steatosis Induced by Thermoneutral Housing in Mice with Diet-Induced Obesity

Preclinical evidence suggests that n-3 fatty acids EPA and DHA (Omega-3) supplemented as phospholipids (PLs) may be more effective than triacylglycerols (TAGs) in reducing hepatic steatosis. To further test the ability of Omega-3 PLs to alleviate liver steatosis, we used a model of exacerbated non-alcoholic fatty liver disease based on high-fat feeding at thermoneutral temperature. Male C57BL/6N mice were fed for 24 weeks a lard-based diet given either alone (LHF) or supplemented with Omega-3 (30 mg/g diet) as PLs (krill oil; ω3PL) or TAGs (Epax 3000TG concentrate; ω3TG), which had a similar total content of EPA and DHA and their ratio. Substantial levels of TAG accumulation (~250 mg/g) but relatively low inflammation/fibrosis levels were achieved in the livers of control LHF mice. Liver steatosis was reduced by >40% in the ω3PL but not ω3TG group, and plasma ALT levels were markedly reduced (by 68%) in ω3PL mice as well. Krill oil administration also improved hepatic insulin sensitivity, and its effects were associated with high plasma adiponectin levels (150% of LHF mice) along with superior bioavailability of EPA, increased content of alkaloids stachydrine and trigonelline, suppression of lipogenic gene expression, and decreased diacylglycerol levels in the liver. This study reveals that in addition to Omega-3 PLs, other constituents of krill oil, such as alkaloids, may contribute to its strong antisteatotic effects in the liver.