PubMed Health⌕ Search

Biomedical subjects

J Farber

Publications and source records attributed to J Farber.

At least 19 recordsLinked to original sources
PubMed1997

Thyroid volume and function after 131I treatment of diffuse non-toxic goitre.

OBJECTIVE: Traditional treatment of diffuse non-toxic goitre are thyroid hormone suppression or surgery. When treating nodular non-toxic goitre with 131I treatment a reduction in thyroid volume to about 50% has been observed. In the present study we evaluated the effect of 131I treatment of diffuse non-toxic goitre. DESIGN: Retrospective study of patients treated for a diffuse non-toxic goitre and followed by evaluation of thyroid volume measured by ultrasound. PATIENTS: Ten selected patients from our out-patient clinic with diffuse non-toxic goitre. MEASUREMENTS: Thyroid volume was measured by ultrasound and thyroid function by serum values of T4, T3, T3 uptake ratio, TSH, TSH receptor antibodies and thyroid peroxidase antibodies (anti-TPO). Measurements were performed before and 1, 3, 6 and 12 months (and 18 months (n = 7), thyroid volume measured in six patients)) after 131I treatment. RESULTS: Thyroid volume declined in all patients from median 41 (range 27-160) ml to 20 (range 9-108) ml over 1 year, a reduction of 47%. One patient developed transient and one persistent hypothyroidism in the follow-up period. Both had elevated anti-TPO levels before treatment (331 and 9185 U/ml) and demonstrated titre increases of 2.5 and 30 times after 3 and 6 months, respectively. Pretreatment values were reached after 1 year. The other eight patients had normal anti-TPO levels and free T4 and T3 indices did not change during follow-up, whereas serum TSH levels demonstrated upward trends within the normal range (P < 0.05). TSH receptor antibodies were normal and remained so in all patients. CONCLUSIONS: 131I treatment of diffuse non-toxic goitre reduces thyroid volume by approximately 50% within 12-18 months. Hypothyroidism, during a limited follow-up period, developed only in patients with positive anti-TPO levels before treatment.

Adult↗
PubMed1994

Plexiform granular cell tumor. A report of two cases.

A previously undescribed variant of granular cell tumor with an interesting plexiform pattern was found in the lower leg of a 10-year-old girl and on the back of a 12-year-old girl. Clinically, the patients presented with intradermal plaques that were accompanied by variable degrees of pain or tenderness. Histopathologic examination revealed granular cell tumors with various sized fascicles, particularly around nerve bundles, in a plexiform pattern. Cytoplasmic granules were PAS positive. Immunohistochemical studies showed tumor cells to be strongly positive with S-100 protein and weakly positive with alpha-1-antichymotrypsin and vimentin. These findings offer further support for a neural origin for granular cell tumors.

Back↗
PubMed1989

WR-2721 reduces bone loss after hindlimb tenotomy in rats.

WR-2721 is a thiophosphate analog of cysteamine that produces hypocalcemia in vivo. Previous studies suggest that WR-2721 produces hypocalcemia by independent inhibitory effects on parathyroid hormone (PTH) secretion, osteoclastic bone resorption, and tubular reabsorption of calcium. We sought to determine if WR-2721 would decrease bone loss in an animal model of disuse osteoporosis produced by unilateral knee tenotomy in the rat. Tenotomy significantly increased osteoclast number in tibias on the side of the procedure compared with tibias on the opposite side which had not undergone the procedure at 3 and 14 days. Femoral weight of tenotomized limbs were also reduced significantly compared with the contralateral limb at 3 and 14 days. WR-2721 treatment (240 mg/kg daily) prevented 26% of the loss of femoral dry weight and 29% of the loss of femoral ashed weight produced 14 days after tenotomy. In addition, WR-2721 treated (240 mg/kg daily) animals had fewer osteoclasts in tenotomized tibias than control animals at 3 days (6.6 +/- 0.7/mm versus 10.3 +/- 0.9/mm, p less than 0.02) and at 14 days (5.8 +/- 0.3/mm versus 8.7 +/- 0.4/mm, p less than 0.02). These data suggest that WR-2721 decreases bone loss in this model by decreasing osteoclastic bone resorption.

Amifostine↗
PubMed1987

An investigation of the metabolism of N-nitroso-N-methylaniline by phenobarbital- and pyrazole-induced Sprague-Dawley rat liver and esophagus derived S-9.

The metabolism and mutagenicity of the esophageal carcinogen N-nitroso-N-methylaniline (NMA) was studied using hepatic and esophageal 9000 X g supernatant (S-9) preparations from Sprague-Dawley rats induced with pyrazole and phenobarbital. Only pyrazole-induced hepatic S-9 was able to dose-dependently activate NMA to a mutagen in the Ames assay and specifically in Salmonella typhimurium TA1537. NMA in the presence of phenobarbital-induced S-9 gave a very weak non-dose dependent mutagenic response. Metabolism of NMA by the two induced hepatic and esophageal S-9 fractions yielded aniline and N-methylaniline (MA). Phenobarbital-induced S-9 from both tissues also afforded phenol, while none was found with the pyrazole-induced preparations. Phenol formation presumably arose from the direct oxidative demethylation of NMA via a benzenediazonium ion (BDI) intermediate. The results indicate that an important metabolic pathway for NMA, with both inducing agents, entails an initial denitrosation to yield MA, which in turn rapidly undergoes oxidative demethylation to aniline. The conversion of NMA to phenol also suggests that direct demethylation of NMA in the phenobarbital-induced system is an important metabolic pathway.

Animals↗
PubMed1983

Activity of mesencephalic dopamine and non-dopamine neurons across stages of sleep and walking in the rat.

Single unit activity of dopamine and non-dopamine neurons in the substantia nigra and ventral tegmental area was recorded across stages of sleep and waking in the rat. These stages consisted of slow wave sleep (SWS), rapid eye movement (REM) sleep, awake-quiet (AQ) and awake-moving (AM). The dopamine neurons showed no change in mean firing rate across the stages of sleep or waking. During REM sleep, however, the dopamine cells fired with a more variable interspike interval than during SWS. In contrast, non-dopamine neurons in the substantia nigra and ventral tegmental area showed large increases in firing rate in REM compared to SWS, and in AM compared to AQ, without showing changes in interspike interval variability. In conclusion, whereas other monoaminergic neurons and various cortical and subcortical neurons exhibit marked changes in firing rate across the stages of sleep and waking, the dopamine neurons are unique in their lack of change in firing rate across stages.

Action Potentials↗
PubMed1983

Dopamine metabolism and receptor sensitivity in rat brain after REM sleep deprivation.

Different dopaminergic mechanisms that could explain behavioral supersensitivity to amphetamine or apomorphine in REM-deprived rats were examined. Four days of REM sleep deprivation induced a highly significant elevation in striatal DOPAC relative to normal controls, but not to stress controls. DOPAC levels in frontal cortex were not affected in any of the groups. Post synaptic D2 receptor number (Bmax) and affinity (Kd) were unchanged in both terminal regions. Similarly, no changes in pre-synaptic receptor sensitivity (apomorphine-induced inhibition of tyrosine hydroxylase) occurred in striatum. A stress control group exhibited no changes in any of the biochemical measures in comparison with either the REM deprived group or unstressed controls. Thus, the enhanced response to dopamine agonists reported previously is not due to altered dopamine receptor sensitivity. Alternative hypotheses to explain enhanced responses to direct and indirect acting dopamine agonists are discussed.

Animals↗
PubMed1981

Phasic influences during REM sleep upon dorsal lateral geniculate nucleus unit activity in the rat.

The single unit activity of dorsal lateral geniculate nucleus cells was recorded in freely moving, unanesthetized albino rats and studied in relation to the sleep-wake cycle and the occurrence of REM sleep ponto-geniculo-occipital (PGO) waves. Spontaneous mean discharge rates are shown to be significantly related to sleep-wake stages, and 70 percent of the units demonstrate a temporal relationship with hindbrain PGO waves. These data are consistent with the existence of a phasic event system in the rat.

Animals↗
PubMed1980

Rapid eye movement sleep PGO-type waves are present in the dorsal pons of the albino rat.

We have found rapid eye movement sleep central phasic activity in the form of episodic, repetitive, monophasic waves in the albino rat. This activity is recorded in discrete areas of the dorso-lateral pons, including the nucleus locus ceruleus. The vast majority of these waves occur during rapid eye movement sleep. Their distribution and electrophysiological characteristics are similar to those of ponto-geniculo-occipital waves in the cat.

Animals↗
PubMed1979

Harm-doing and victim's racial or orthopedic stigma as determinants of helping behavior.

Three experiments tested a prediction derived from an ambivalence theory of behavior toward the stigmatized. The prediction was that unintentional harm-doers would be more likely to make restitution by doing a favor for a stigmatized victim than for a nonstigmatized one. In Experiment 1 it was upheld for black versus white victims. In Experiment 2, where the victim of harm-doing was either physically handicapped or normal, the prediction was upheld only among older subjects, following the post hoc introduction of an age variable. Experiment 3 also used a physical disability variable. The data were consistent with the prediction, although the adequacy of the harm-doing manipulation was not checked empirically. On the whole, these results are seen as complementing previous findings of amplified post-harm-doing denigration of black and disabled victims. An assumption that the relationship between harm-doing and altruism was mediated by guilt arousal received only fragmentary support. That is, self-reports of guilt were highest in the harm-doing black confederate condition in Experiment 1, and self-reports of negative affect were highest in the harm-doing/wheelchair confederate condition in Experiment 3, but there were no significant relationships between individual differences in guilt or negative affect on the one hand, and amount of helping, on the other.

Adolescent↗