Carcinoma of the gallbladder presenting as scalp tumour

Carcinoma of the gallbladder is characterized by rapid tumour growth associated with lymphatic and local tumour invasion. The peritoneum, GIT and lungs are common sites of seeding. Distant metastasis to bone rarely occurs. Here we document a case of silent gallbladder carcinoma presenting as scalp tumour with improved survival.

Kluver Bucy syndrome in young children

For the first time, Kluver Bucy syndrome (KBS) is described in young children who had no environmental learning of sex. The syndrome has so far been noted only in adults after bilateral temporal lobe affection. A few of its components, especially the hypersexuality and hypermetamorphosis, are likely to manifest differently in very young children. Seven patients in the pre-pubertal age group, who developed KBS as a post-encephalitic sequelae, are described. The patients, 2.5-6 years old, suffered from acute herpes simplex encephalitis (HSE) at 10 months-5.5 years of age and developed KBS on regaining consciousness and ambulation. Altered emotional behaviour, changes in dietary habits, hyperorality and hypersexuality were present in all, while psychic blindness and hypermetamorphosis were noted in a few of the patients. All showed marked indifference and lack of emotional attachment towards their close relatives. Apathy and easy distractibility were rare. Bulimia and strong urge to put non-food items into the mouth were common. Hypersexuality manifested as frequent holding of genitals, intermittent pelvic thrusting movements and rubbing of genitals to the bed on lying prone. Due to lack of environmental learning of sex and also, due to emotional and physical dependence on parents, the manifestations in young children showed modification over those of adults.

Time dependent selective recurrent discharge of motor units in F-response

The interaction among the recurrent discharge of motor units is studied in surface recorded composite F-response. In the first experiment, 200 serially elicited polyphasic F-responses from foot muscles of patients with different lower motor neurone (LMN) disorders were rearranged to understand the behaviour of individual negative and positive peaks. These peaks were considered on the basis of simultaneous recording with a single fibre EMG needle, to be the partial expression of either a single motor unit potential (MUP) or more than one MUP generated simultaneously. In another experiment, two serially averaged F-responses (50 each) were superimposed over each other to look for their similarities at 15 min intervals 6 times. Result analysis indicated interaction of MUPs by in-phase summation and out-of-phase subtraction. Less affected MUPs recurred as negative or positive peaks in morphologically different F-responses. Certain peaks were observed more frequently than the others. Two serially averaged F-responses were nearly identical on superimposition over each other but their morphologies differed at different time intervals. The study suggests more frequent generation of F-response in a specific group of alpha motoneurones at one point of time, which is replaced by another group at another point of time. The characteristic variation in F parameters is, however, mainly due to the interaction of these frequently generated F-response MUPs with other sporadically generated ones. This interaction can be appreciated on visual screening of F-responses in patients with lower motor neurone disorders, perhaps because of a reduction in the number of participating MUPs.

"Extensor toe sign" by various methods in spastic children with cerebral palsy

Upper motor neuron lesion in adults is usually associated with spasticity and "extensor toe sign" on plantar stimulation (extensor plantar response). There are various methods of eliciting this sign including the classic method by Babinski. Other methods produce this response when the area of reflexogenic zone is increased due to upper motor neuron lesion. There are varying reports of Babinski positivity in spastic cerebral palsy. This study was undertaken to assess the sensitivity of different methods of eliciting "extensor toe sign." An attempt has also been made to correlate the severity of spasticity with the combined "extensor toe sign" positivity by various methods and with the increase in reflexogenic zone. Eighty-one children with spastic cerebral palsy were examined. Twelve had hemiplegia; therefore, a total of 150 limbs were tested. "Extensor toe sign" was elicited by 12 different methods in each patient. The sensitivity of each method was calculated and compared with each other one. The assessment of spasticity was done using the Ashworth Tone Scale. The severity of spasticity was correlated with "extensor toe sign" positivity using various methods. Classic Babinski reflex was positive in 75% of cases, whereas Gonda-Allen sign was positive in 90% of cases followed by Allen-Cleckley (82%), Chaddock (74%), and Cornell (54%). All other signs had sensitivity of less than 30%. There was no increase in sensitivity after combining them. There was significant negative correlation between the spasticity and the combined "extensor toe sign" positivity (by all the methods). This study, therefore, suggests that the majority of patients with spastic cerebral palsy have positive "extensor toe sign." The Gonda-Allen method is more sensitive than the classic Babinski method. A positive "extensor toe sign" is negatively correlated to the degree of spasticity.

Chemosensitivity of advanced larynx carcinoma cells in vitro and significance of multidrug resistance markers in these tumors

Thirty cases of previously untreated advanced larynx carcinoma were checked for in vitro chemosensitivity and presence of the resistance markers viz. P-glycoprotein (P-gp) glutathione-S-transferase-pi (GST-pi) and protein kinase C (PKC) overexpression. The cytotoxicity testing was done using MTT assay and the resistance markers were checked by immunohistochemical methods using monoclonal antibodies. The drug combinations employed in MIT assay were 5FU* + MTX*, 5FU + cisPt*, 5FU + Mito*, cisPt + Mito and MTX + Mito (*5FU = 5Fluorouracil, MTX-methotrexate, cisPt-cisplatin and Mito = mitomycin C). No statistically significant correlation was observed between resistance to the above drug combinations and presence of the resistance markers under consideration. A statistically significant correlation was observed between node positivity and expression of resistance markers which indicates that presence of one or more of these markers in these tumors may be considered as a negative prognosis marker. CisPt-Mito was found to be the most effective drug combination in vitro, in the cases studied.

Acute disseminated encephalomyelitis presenting as ataxic hemiparesis

A patient of acute disseminated encephalomyelitis (ADEM) with a rare clinical presentation is described. The temporal profile of the disease suggested parainfectious central demyelination. The magnetic resonance imaging (MRI) also showed large demyelinating lesions scattered bilaterally in the cerebral white matter, thalami and brain stem. However, clinically he had only right ataxic hemiparesis and dysphasia without any impairment of cognition or consciousness.

Measurement of magnetization transfer in different stages of neurocysticercosis

The purpose of this study was to establish magnetization transfer ratio (MTR) in different stages of neurocysticercosis. A total 2,532 cysticerci were studied prospectively in 15 cases. MTR from different regions of the lesions (ie, the cyst, the protoscolex or mural nodule, the granuloma wall) were calculated in different stages of evolution/degeneration in all cases. Of a total 2,532 lesions studied, 2,261 (89.29%) were seen on routine spin-echo (SE) imaging. The rest of the lesions were only seen on magnetization transfer (MT) SE imaging. Maximum MTR was calculated from healing lesions (mean + SD = 31.0+/-2.8) and from the core of SE invisible lesions (30.0+/-5.1). Innocuous cystic lesions, which were hyperintense on T2-weighted images, did not show any MT (MTR = 5.10+/-1.2), whereas degenerating T2 hyperintense lesions showed MTR of 26.40+/-2.7. Nondegenerating and degenerating scolices showed an intermediate MTR of 21.7+/-3.3 and 15.0+/-4.5, respectively. MT varies between different parts of the lesion and also from the same part in different stages of evolution/degeneration of the lesion. The visibility of a lesion on MT-SE sequence was dependent on its MTR and its location at a particular site (cortical gray matter, white matter, or deep gray matter). The difference in MTR of the lesion and the surrounding brain parenchyma decides the resulting contrast and visibility of the lesion.

Isolation, characterization and baculovirus-mediated expression of the cDNA encoding cytosine DNA methyltransferase from Pisum sativum

A series of overlapping clones complementary to the Arabidopsis cytosine-5 DNA methyltransferase (C-5 MTase) has been isolated from pea cDNA libraries. The assembled nucleic acid sequence contains an open reading frame of 4761 bp encoding a protein of 1554 amino acids. Like other eukaryotic C-5 MTases, the inferred protein has a presumed regulatory N-terminal region linked to a catalytic C-terminal domain, which has eight of the ten conserved motifs found in prokaryotic C-5 MTases. The pea C-5 MTase has 65% identity at the nucleotide level and 61% identity at the protein level, with the Arabidopsis C-5 MTase. The catalytic domain of the pea enzyme shares 78% identity with Arabidopsis and approximately 52% identity with murine and human C-5 MTases, including the relative position of the proline-cysteine dipeptides of the catalytic centre. Using the conserved region of the cDNA as a probe, we have identified a transcript of 5 kb. Southern blot analysis of pea genomic DNA with the above probe indicates the presence of a single gene. Using poly(A)+ RNA from different developmental stages and different tissues, we have observed that expression is confined mostly to the rapidly dividing tissues of the plant. Expression of this assembled cDNA in a baculovirus system gives a protein of approximately 174 kDa. The expressed protein can be cross-linked, in an AdoMet-dependent manner, to duplex oligonucleotide substrates containing FdC in place of target cytosines in either CG or CAG/CTG sequences.

Comparison of low molecular weight heparin (Fragmin) with sodium heparin for prophylaxis against postoperative thrombosis in women undergoing major gynaecological surgery

A randomized controlled trial was undertaken comparing the efficacy and safety of low molecular weight (LMW) heparin (Fragmin) with sodium heparin for prophylaxis against postoperative thromboembolic disease after major gynaecological surgery. Women were randomized to receive subcutaneous injections of 5,000 U of either once daily LMW heparin or twice daily sodium heparin. A total of 566 women were recruited, of whom 552 completed the study. Most women (461) had malignant disease and 430 of these underwent radical surgery. The remainder underwent major, but not radical surgery. There were 5 thromboembolic events in the LMW heparin group and 2 in the sodium heparin group, with no significant difference between these groups. No significant difference was found in the incidence of intraoperative or postoperative transfusion in the 2 groups. The decision of which heparin to use in routine practice cannot be made on clinical grounds.

Baculovirus-mediated expression and characterization of the full-length murine DNA methyltransferase

The original cDNA sequence reported for the murine DNA methyltransferase (MTase) was not full length. Recently, additional cDNA sequences have been reported that lie upstream of the original and contain an extended open reading frame with three additional ATGs in frame with the coding region [Tucker et al . (1996) Proc. Natl. Acad. Sci. USA , 93, 12920-12925; Yoder et al . (1996) J. Biol. Chem . 271, 31092-31097]. Genomic DNA upstream of this ATG contains two more ATGs in frame and no obvious splice site. We have constructed, and expressed in baculovirus, MTase clones that begin at each of these four ATGs and examined their properties. Constructs beginning with any of the first three ATGs as their initiator methionines give a predominant DNA MTase band of approximately 185 kDa on SDS-PAGE corresponding to translational initiation at the third ATG. The fourth ATG construct gives a much smaller protein band of 173 kDa. The 185 kDa protein was purified by HPLC, characterized by mass spectrometry and has a measured molecular mass of 184 +/- 0.5 kDa. All of these MTases were functional in vitro and steady state kinetic analysis showed that the recombinant proteins exhibit similar kinetic properties irrespective of their length. The homogeneous recombinant enzyme from the fourth ATG construct shows a 2.5-fold preference for a hemi-methylated DNA substrate as compared to an unmethylated substrate, whereas the 185 kDa protein is equally active on both substrates. The kinetic properties of the recombinant enzyme are similar to those reported for the native MTase derived from murine erythroleukemia cells. The new clones are capable of yielding large quantities of intact MTases for further structural and functional studies.

Interpatient variability: genetic predisposition and other genetic factors

Polymorphisms and other genetic factors related to enzymes metabolizing drugs and xenobiotic chemicals are well known. This article focuses on selected molecular mechanisms and introduces some of the clinical implications arising from genetically determined interpatient variability or expression in some of these enzymes. Selected are the polymorphic enzymes of cytochromes P-450 (CYP) as examples of phase I enzymes and methyl transferases, n-acetyl transferases, and glutathione-s-transferases as examples of phase II enzymes. The polymorphism surrounding arylhydrocarbon hydroxylase induction is briefly described. Phase I enzymatic reactions are predominantly oxidative, whereas phase II reactions often couple with the byproducts of phase I. Overall, in poor metabolizers, whether phase I or phase II, there is limited metabolism in most patients unless another major metabolic pathway involving other enzymes exists. Drug metabolism also depends on whether the parent compound is a prodrug that forms an active metabolite, and poor metabolizers under this condition will form only trace amounts of an active compound. Therefore, the clinical significance of genetic polymorphisms and other genetic factors may be related to substrate, metabolite, or the major elimination pathway.

Leigh's disease : analysis of clinical and imaging characteristics with possible therapeutic implications

The symptoms and signs of Leigh's disease are so variable that the diagnosis is extremely difficult. The disease was so far being confirmed only at autopsy. Antemortem clinical diagnosis, however, is important, as some of these patients may respond to high dose of vitamin B-1. We report two patients of Leigh's disease suspected clinically and confirmed on MR imaging. Both the patients responded partially to parenteral thiamine and subsequently remained stable on convenient oral dosage during one year of observation. Follow-up MRI done on patient showed resolution of some of the lesions, no change in some and appearance of some new lesions. There was no definite correlation between the thiamine related clinical recovery and the structural changes observed on MRI. The extreme rarity of involvement of medulla and cervical spinal cord as observed in one of the patients and of external capsule as seen in the other patient, is highlighted.

Selective involvement of basal ganglia and occipital cortex in a patient with acute endosulfan poisoning

We report a teenage girl with acute endosulfan poisoning who developed psychosis, generalized tonic-clonic seizures, myoclonic jerks, cortical blindness and limb rigidity. Serial magnetic resonance imaging (MRI) showed bilateral reversible lesions localized to caudate nucleus, putamen and occipital cortex; internal capsule and thalamus were spared. This selective involvement may have a bearing on mechanisms underlying endosulfan toxicity.

Parainfectious myelitis: three distinct clinico-imagiological patterns with prognostic implications

Seventeen parainfectious myelitis patients were studied for site, extent and severity of lesions. Three patterns were observed each having distinct clinical, electrophysiological and MRI features: 1) focal segmental myelitis--focal cord lesion with long tract signs and good prognosis; 2) ascending myelitis--continuous lesion from conus to mid-cord with upper and lower motor neuron signs (not necessarily spinal shock), dysautonomia and poor outcome; 3) disseminated myelitis--discrete lesions scattered throughout the cord with subtle signs in spinal segmental distribution, above and below the transverse level and moderate outcome. Severe autonomic dysfunction, denervation of paraspinal muscles, "dense" lesion on imaging and often (but not always) the absent somatosensory evoked potentials carried poor outcome. In conclusion "parainfectious myelitis" is a better term to describe transverse myelitis, as the lesion extends to a large vertical extent. Further classification into 3 subgroups may improve understanding of anatomical and physiological dysfunction and prediction of outcome.

Magnetic resonance imaging in juvenile asymmetric segmental spinal muscular atrophy

Magnetic resonance imaging (MRI) of cervical spine was performed in 16 patients of juvenile asymmetric segmental spinal muscular atrophy (JASSMA) in neutral and flexed positions to look for abnormalities in the spinal cord and the surrounding structures. The study included 5 normal individuals and 5 disease-negative controls who had spinal cord atrophy due to amyotrophic lateral sclerosis. In normal and disease-negative controls, lower cervical spinal cord moved forward and got mildly flattened against the vertebral bodies during flexion. The subarachnoid space increased behind the cord with no significant forward movement of the posterior dura mater; epidural space was just visible. The patients of JASSMA showed spinal cord atrophy in a small vertical segment in front of cervical 4 to 7 vertebral bodies. In addition, 9 patients had high cord signal on T2 weighted images, mainly localized to anterior and lateral horns of the grey matter. In flexion, there was marked anterior displacement and anteroposterior flattening of lower cervical cord against the vertebral bodies; posterior dura mater also moved forward obliterating subarachnoid space in all the patients. A large posterior epidural space was visible which showed enhancement after gadolinium-DTPA administration. Twelve patients had prominent blood vessels in this epidural space. These findings suggest that MRI done in neck flexion may have diagnostic significance in JASSMA.

Proportion and pattern of dystrophin gene deletions in north Indian Duchenne and Becker muscular dystrophy patients

Population-based variations in frequency and distribution of dystrophin gene deletions have been recognized in Duchenne/Becker (DMD/BMD) muscular dystrophy patients. In the present study, DNA samples from 121 unrelated DMD/BMD patients from North India were analyzed for deletional studies with multiplex PCR and Southern hybridization. A total of 88 (73%) patients showed intragenic deletions in the dystrophin gene. The observed proportion of gene deletions is relatively high, particularly compared with that of Asian counterparts. However, the distribution of breakpoints across the gene does not show significant variations.

Genotype-phenotype correlation in Duchenne/Becker muscular dystrophy patients seen at Lucknow

The molecular basis of two allelic forms of muscular dystrophy, Duchenne (DMD) and Becker (BMD), has been explained by frame shift hypothesis. In order to test this hypothesis, deletional mutations in 59 patients confirmed to have DMD and 11 BMD patients were analysed using multiplex polymerase chain reaction and Southern hybridization with dystrophin cDNA probes. Translational reading frame of the dystrophin gene was derived from 'Border type' analysis of exons flanking the intragenic deletions. The correlation between genotype (reading frame) and phenotype (clinical severity) showed higher number of DMD patients (approximately 20%) deviating from the frame shift hypothesis. The patients who deviated had deletions at the central hot spot region of the dystrophin gene. The presence of these deviations in a large number of DMD patients highlights the difficulties in predicting the clinical progression of the disease based only on DNA profile.

F-response multiplicity in lower motor neuron disorders

Multiple F-response following a single supramaximal distal nerve stimulation was observed in about 4% of the patients suffering from disorders of lower motor neuron. The phenomenon was observed in old poliomyelitis, entrapment neuropathies, axonopathies and demyelinating neuropathies. Thirty healthy subjects and 30 patients of upper motor neuron disorder were also studied for this purpose but none showed F-multiplicity. On repeated stimulation at sufficient intervals, some or all the components of the multiple F-response could be reproduced individually or in different combinations with similar latency and morphology. These responses had all the characteristics of F-response and were distinguishable from H-reflex or axon reflex. Increase in the number and frequency of repeater F-response and markedly increased chronodispersion were also observed consistently in association with multiple F-responses. Multiplicity in the F-response is a hitherto unknown phenomenon of relatively rare occurrence, presence of which however, is always indicative of disease of the lower motor neuron. The possible mechanisms of its generation are discussed.

Antemortem diagnosis of Leigh's disease: role of magnetic resonance studies

A two-and-a-half-year-old male child presented with recurrent attacks of intractable vomiting, psychomotor retardation since 14 months of age. He had also lower cranial nerve palsy and corticospinal involvement. Magnetic resonance imaging had shown multiple well circumscribed areas of hypointusity in T1 weighted image which were brightly hyperintense in heavily T2-weighted image. The lesions were seen in basal ganglia, thalamii and brainstem and spared mamillary bodies. Magnetic resonance spectroscopy demonstrated lactate peak in the affected areas confirming the diagnosis of Leigh's disease. The child responded well to large dose of vitamin 'B' therapy.

DNA binding and methyl transfer catalysed by mouse DNA methyltransferase

By using a purified fraction of mouse DNA methyltransferase we have shown, by gel-retardation analysis, that the enzyme forms a low-affinity complex preferentially with hemimethylated DNA; the complexes formed with unmethylated or with fully methylated DNA are of even lower affinity, and only very weak interaction occurs with DNA lacking CG dinucleotides. Interaction is inhibited by N-ethylmaleimide. Methyl transfer from S-adenosyl-methionine is associated with the release of the fully methylated product from the complex. Complexes formed with the intact enzyme are extremely large, but limited trypsin treatment allows a major complex to enter the gel. DNA binding is not inhibited by this limited proteolysis of the native enzyme.

Central pontine myelinolysis following 'slow' correction of hyponatremia

Two patients with central pontine myelinolysis are described for the peculiar mode of development. Both patients were in chronic renal failure and admitted in a stuporous state due to hyponatremia. Both developed central pontine myelinolysis during the hospital stay following slow and judicious correction of hyponatremia. The role of chronicity of hyponatremia prior to its correction, in the genesis of central pontine myelinolysis, particularly in the patients who have chronic debilitating illness, septicemia or malnutrition, is highlighted.