Biomedical subjects

J Vaid

Publications and source records attributed to J Vaid.

At least 19 recordsLinked to original sources

PubMed1995

Reversible hepatic dysfunction in association with cyclophosphamide therapy.

A 5.5-year-old child with nephrotic syndrome was treated with cyclophosphamide. After 9 weeks of therapy she developed jaundice and abnormal liver function tests. No infective aetiology was found and the abnormal liver function tests resolved within 5 weeks of discontinuing cyclophosphamide. Cyclophosphamide has rarely been reported to cause liver dysfunction, but not in children treated for nephrotic syndrome, and paediatricians should therefore be aware of its potential for inducing reversible hepatic dysfunction.

Child, Preschool↗

PubMed1993

Activation of number facts in bilinguals.

Two experiments examined the effect of the presentation format of numbers--digits versus word format in the first and in the second languages of bilinguals--on mental arithmetic. Speed of number-fact retrieval and the presence of interference produced by numbers that were either numerically close to or associatively related to the correct answers of stored arithmetic problems (e.g., 2+5 and 7x8) were compared across formats. The verification of true problems was increasingly slower and less accurate from the digit condition to the second-language condition. Interference was produced by both types of incorrect answers in the digit and first-language conditions, whereas in the second-language condition, it was constrained to answers that were numerically close to correct answers. Together, the results suggest that the retrieval of arithmetic facts and the automatic spreading of activation within the network of numerical facts are not only language-sensitive, but format-sensitive in general.

Adolescent↗

PubMed1992

The linguistic basis of left hemisphere specialization.

In humans the two cerebral hemispheres of the brain are functionally specialized with the left hemisphere predominantly mediating language skills. The basis of this lateralization has been proposed to be differential localization of the linguistic, the motoric, or the symbolic properties of language. To distinguish among these possibilities, lateralization of spoken language, signed language, and nonlinguistic gesture have been compared in deaf and hearing individuals. This analysis, plus additional clinical findings, support a linguistic basis of left hemisphere specialization.

Adult↗

PubMed1992

Biological action of lantadene C, a new hepatotoxicant from Lantana camara var. aculeata.

Lantadene C (22 beta-2-methylbutanoyloxy-3-oxoolean-12-en-28-oic acid) isolated from the leaves of the hepatotoxic plant Lantana camara var. aculeata (Red) has been found to be identical with dihydrolantadene A reported earlier. Molecular structure of lantadene C has been deduced from single crystal X-ray diffraction analysis. It resembles lantadene A in the pentacyclic portion of the molecule but differs in the side chain region. Atom C-34 is cis to C-35 in lantadene C but is trans in lantadene A. Semisynthetic lantadene C was prepared by catalytic hydrogenation of lantadene A. Lantadene C was obtained in two forms, I and II. Form I was crystalline while form II was amorphous. Unlike lantadene A, both form I and II of lantadene C elicited strong hepatotoxic response in guinea pigs associated with decrease in fecal output, feed intake, hepatomegaly, hepatic injury at the cellular and subcellular level, increase in plasma bilirubin, and acid phosphatase activity. All the clinical signs, hepatic lesions, and changes in blood plasma typified lantana toxicity. This is the first report on the hepatoxicity of lantadene C. The interrelation of molecular structure and biological activity of lantadene A and C has been discussed.

Acid Phosphatase↗

PubMed1991

The enzymatic profile of urine and plasma in bovine urinary bladder cancer (enzootic bovine haematuria).

The enzymatic profile of urine and plasma in field cases of bovine bladder cancer was studied. Urinary lactate dehydrogenase activity was significantly altered along with the isoenzyme pattern. Activity of alkaline phosphatase and beta-glucuronidase was decreased in the affected animals. No significant changes were observed in acid phosphatase, or arylsulphatase A and B activity. In plasma, lactate dehydrogenase activity was elevated without any change in the isoenzyme pattern. No significant changes were observed in the other plasma enzymes studied or in the sialic acid concentration.

Alkaline Phosphatase↗

PubMed1991

Bacteraemia in man and animals: an overview.

Bacteraemia signifies invasion of the bloodstream by bacteria. In most systemic infections in man and animals, bacteria enter the blood at some stage during the infection and are rapidly distributed throughout the body. A wide variety of organisms have been associated with bacteraemia. Prompt detection of the aetiological agents of bacteraemia is of prime importance in clinical microbiology. There are no defined recommendations for blood cultures in animals but both conventional and improved methods are available for detection of bacteraemia in man. The consequences of bacteraemia are as diverse as the potential aetiological agents. Monoclonal antibodies to the core glycolipid (lipid A) seems very promising for the treatment of bacteraemia and septic shock caused by Gram-negative bacteria in man and animals.

Animals↗

PubMed1991

Sentence interpretation in normal and aphasic Hindi speakers.

In interpreting a sentence, listeners rely on a variety of linguistic cues to assign grammatical roles such as agent and patient. The present study considered the relative ranking of three cues to agenthood (word order, noun animacy, and subject-verb agreement) in normal and aphasic speakers of Hindi. Because animacy plays a grammatical role in Hindi (determining the nature and acceptability of sentences without accusative marking), this language is relevant to the claim that Broca's aphasia involves a dissociation between grammar and semantics. Results of Study 1 with normal Hindi-dominant speakers showed that animacy is the strongest cue in this language, while agreement is the weakest cue. In Study 2, Hindi-English bilinguals were tested in both their languages. Most showed the normal animacy-dominant monolingual pattern in Hindi, with a mixture of strategies from both languages in their interpretation of English. A substantial minority showed mixed strategies in both languages. Only 5 of 48 subjects displayed a complete separation between languages, with animacy dominance in Hindi and word order dominance in English. In Study 3, two Hindi-English bilinguals with Broca's aphasia were tested in both languages. Results indicate (a) greater use of animacy in Hindi than in English and (b) greater use of word order in English than in Hindi. The strategies displayed by these patients fall well within the range observed among bilingual normals. We conclude that the use of animacy in sentence interpretation by these aphasic patients reflects preservation of normal, language-specific processing strategies; it cannot be interpreted as a nonlinguistic strategy developed to compensate for receptive agrammatism. Results are discussed in light of other cross-linguistic evidence on sentence comprehension in monolingual and bilingual aphasics.

Adolescent↗

PubMed1991

Incidental memory for format of presentation of number stimuli: evidence from monolinguals and bilinguals.

Are numerical stimuli represented in an abstract code or is information about surface format preserved in memory? Three experiments bearing on this issue are reported. All used an incidental recall procedure. Two experiments examined memory for numeral versus word format in monolinguals and the third examined memory for words in the first versus second language of Spanish-English bilinguals. Across all studies, memory for format of number presentation was above chance and was as high as 76% under certain conditions. Implications for number representation are discussed.

Adult↗

PubMed1991

An outbreak of aflatoxicosis in Angora rabbits.

An outbreak of aflatoxicosis in Angora rabbits involving a large number of rabbitries was investigated. Mortality was more in weaners than in adults. Affected animals showed anorexia, dullness and weight loss followed by jaundice in terminal stages. Death occurred within 3-4 d of the appearance of clinical signs. Livers were moderately to severely congested, icteric and were hard to cut. Gall bladders were distended and had inspissated bile. Liver sections showed degenerative changes of hepatic cells along with dilatation and engorgement of sinusoids. Bile ducts had mild to severe periportal fibrosis. Focal areas of pseudolobulation and regenerative foci were also predominant. The level of aflatoxin B1 in feed samples from various farms submitted at the time of the investigation varied from 90 to 540 ug aflatoxin B1/kg of feed. Withdrawal of feed and supplementary therapy resulted in gradual disappearance of signs and mortality.

Aflatoxins↗

PubMed1990

Hemispheric involvement in shadowing vs. interpretation: a time-sharing study of simultaneous interpreters with matched bilingual and monolingual controls.

A time-sharing study used shadowing and interpretation/paraphrasing tasks to evaluate lateralization in professional interpreters individually matched to bilingual and monolingual controls. A two-step multivariate general linear model procedure was used to determine lateralized effects and extent of disruption produced by the tasks. Results revealed the monolingual group to be left lateralized for both tasks, but the two bilingual groups were lateralized in the LH only for shadowing. The monolingual group was significantly different from the bilingual groups in the pattern of hand asymmetry for interpretation/paraphrasing. The findings replicate outcomes of prior repeated measures analysis of variance procedures on percentage of change scores. However, new information is added by the more refined analysis. The findings are also discussed in terms of previous laterality studies using similar tasks and subject samples.

Adult↗

PubMed1989

Erythrocyte glutathione and its metabolizing enzymes in bovine urinary bladder cancer.

Glutathione and its metabolizing enzymes were studied in erythrocytes of cattle suffering from urinary bladder cancer and associated hematuria. The concentration of glutathione (GSH) and GSH peroxidase activity were subnormal in the affected animals, whereas activities of GSH reductase and GSH S-transferase were not altered. Decreased GSH and GSH peroxidase are likely to make erythrocytes of the affected animals more susceptible to oxygen-induced injury and the radiomimetic effect of bracken fern.

Animals↗

PubMed1989

Asymmetries in the perception of facial affect: is there an influence of reading habits?

Perceptions of happy facial affect from asymmetric composite faces presented in free vision were compared in four groups: left-to-right readers (Hindi), right-to-left readers (Arabic), left-to-right and right-to-left readers (Hindi/Urdu) and illiterates (Hindi/Urdu). Right- and left-handed users of Hindi and Urdu were studied. The analysis of asymmetry scores revealed a significant effect of Group, such that a left hemifield preference was present only in the left-to-right (Hindi) group. There were no reliable differences between right- and left-handers. Furthermore, the leftward bias was present in a significantly larger proportion of Hindi than Urdu or Arabic readers. These results are taken to reflect an interaction between a cerebral laterality effect and a directional scanning effect in facial affect judgment.

Adult↗

PubMed1989

Hand dominance for signing: clues to brain lateralization of language.

Virtually all right-handed individuals are left hemisphere dominant for language. Sign languages of the deaf provide an unusual vehicle for exploring the link between handedness and hemispheric specialization for language since in sign language the hands themselves are the language articulators. Performance of the right and left hand was examined in deaf native users of American Sign Language (ASL) for speeded production of one-handed signs and for shadowing of signed discourse. Opposite patterns of asymmetries in hand performance were found in right- and left-handers. However, left-handers were more flexible than right-handers in signing with their non-preferred hand. Furthermore, unusual patterns of hand use for sign were found in a deaf signer with a left hemisphere lesion, possibly indexing increased mediation of the intact hemisphere. Implications for brain organization of language in a visual-gestural mode are discussed.

Adult↗

PubMed1989

Visual field asymmetries in numerical size comparisons of digits, words, and signs.

Visual field asymmetries were examined in American Sign Language-English bilinguals for speeded numerical size judgments of pairs of digits, number words, and number signs. Physical size of the number pairs was either congruent or incongruent with their numerical size. The results revealed a greater left visual field (LVF) interference for numbers represented as digits and a greater right visual field (RVF) interference for numbers represented as words or signs. Subjects' performance on number words and signs was also influenced by their skill in English and ASL: interference was greater in the RVF in the subjects' better language but was greater in the LVF for the less skilled language. These findings suggest that lateralization of numerical size judgments is moderated by the mode of number presentation and by prior language experience.

Adult↗

PubMed1989

Mirror writing: an advantage for the left-handed?

It has been claimed that left-handed individuals are better than right-handers at writing in a mirror script (R. Tankle & K. Heilman, 1983, Brain and Language, 19, 115-123). We tested this claim by comparing the mirror writing ability of normal right- and left-handed adults as a function of hand used and hand use order. Our results do not support the notion of a left-hander superiority in mirror writing since, in two different experiments, right-handed individuals were found to be as good as left-handers. Instead, we obtained evidence for an order effect such that in both experiments, mirror writing was faster in those who started the task with their right hand.

Adult↗

PubMed1988

Asymmetries in tachistoscopic word recognition: scanning effects re-examined.

To investigate the role of scanning biases in visual half field studies, native readers of Hindi (a language written and read from left-to-right) and Urdu (a language written and read from right to left) were tested in a language analogue of the Stroop paradigm. Subjects had to identify the script (Hindi vs. Urdu) in which the words referring to the two languages Hindi and Urdu were presented. Greater RVF than LVF interference was obtained in both groups, indicating a left hemisphere specialization for lexical functioning independent of scanning biases.

Dominance, Cerebral↗

PubMed1988

Erythrocyte membrane alterations in enzootic bovine hematuria.

Erythrocyte membrane enzymes and chemical constituents were studied in animals presenting enzootic bovine hematuria (EBH) and in normal animals. Mg2+-ATPase, Na+, K+, Mg2+-ATPase and ouabain insensitive Na+, K+, Mg2+-ATPase activity were decreased significantly in the affected animals. Cholesterol:phospholipid and sialic acid:phospholipid ratios also decreased in animals suffering from EBH. No significant changes were found in acetylcholinesterase, sialic acid, sulfhydryl groups and cholesterol in membranes of affected animals.

Animals↗

PubMed1987

Visual field asymmetries for rhyme and syntactic category judgments in monolinguals and fluent early and late bilinguals.

A tachistoscopic study investigated hemispheric specialization among monolingual and fluent French-English bilingual adults for speeded rhyme and syntactic category matching. A right visual field superiority was obtained for both types of verbal judgments. This effect was more pronounced in late bilinguals than in early bilinguals or monolinguals. In addition, bilingual subgroup differences in response latency and strategy were found, suggesting a preference for semantic processing among early bilinguals and for surface processing among late bilinguals, consistent with previous findings. Possible theoretical implications of these differences are outlined.

Adult↗