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We have investigated the possibility that structural alterations of the 'nuclear' oncogene family (c-myc, N-myc, L-myc, fos, myb and p53) leading to aberrant expression might, as in several other tumour types, play a role in the multi-stage development of tumorigenesis in the human thyroid follicular cell. Direct analysis of expression by slot and Northern blot RNA hybridisation showed that normal thyroid expresses surprisingly high levels of fos, and to a lesser extent c-myc, c-myc expression was markedly increased in all tumours, both benign and malignant, but no increase was seen in any other nuclear oncogene. fos expression was reduced specifically in one type of malignant tumour-follicular carcinoma-in inverse correlation with differentiation. Southern blot analysis showed no evidence of rearrangement or amplification of c-myc, or of any other 'nuclear' oncogene in any thyroid tumour. We conclude that there is no evidence that a primary abnormality of these genes plays a role in thyroid follicular cell tumorigenesis and suggest that the observed changes in expression can be adequately explained as secondary consequences of the tumour phenotype. Images Figure 1 Figure 2 Figure 3

The possibility of an association between restriction fragment length polymorphisms (RFLPs) at the Ha-ras gene locus and susceptibility to develop colorectal cancer has been investigated. Leucocyte DNA from 46 carcinoma patients and 49 controls was analysed by Southern blotting to determine the size distribution of restriction fragments containing the variable tandem repeat 3' to the Ha-ras gene. Four predominant allelic fragments were found in both groups (in AvaII digests having sizes of 1.55, 2.0, 2.65 and 3.15 kilobases [kb]), together with a variety of 'rare' alleles (with individual frequencies less than 5%). The overall prevalence of rare alleles was not significantly different between cancer and control groups. The distribution of the common alleles, however, differed significantly. The combined frequency of the two larger alleles (a3 and a4) was approximately twice as high in the cancer group (34%) as in controls (18%) (P less than 0.025), which was reflected in a highly significant increase in the proportion of individuals carrying an a3 or a4 allele. Images Figure 2 Figure 3

A recombinant murine retroviral vector encoding the SV40 virus large T antigen was used to infect stably an immortal line of differentiated rat thyroid epithelial cells, FRTL-5. Expression of SV40 T transformed these cells to anchorage independence and tumorigenicity but did not alter morphology or abolish tissue-specific functions and growth factor requirements. The resulting phenotype provides a model of well-differentiated human thyroid cancer. Images Figure 1 Figure 3

A questionnaire was sent to all the estimated 200 hospital departments providing nuclear medicine imaging services in the UK. Replies were received from 162 (81%). The questionnaire was brief, but covered a wide range of aspects of a nuclear medicine service. While all responses showed departments to have some quality control procedures in operation, they were often not used correctly. In most departments there appears to be scope for improvement so that departmental managers can monitor more closely the quality of service provided.

125I emits no β rays but part of its soft γ radiation is transformed into low energy electrons. Considering the short tissue path length (2-5 μm) of these electrons, it was postulated that its radiation effect on the thyroid might be different from that of 131I (path length 2000 μm). An experiment was designed to compare the biological effect of several dose levels of radiation from 125I on the rat thyroid gland with that from 131I. The effect of varying doses of each isotope on goitrogenesis (methylthiouracil induced) and on thyroid/serum radioiodide concentration (T/S) ratio was measured in animals radiated while on either a normal or a low iodide diet. In relation to 131I, the effect of 125I on goitrogenesis generally was much less than its effect on function. The low iodide diet group given 125I, surprisingly, showed markedly less inhibition of goitrogenesis than the normal diet group, an opposite effect to that attained with 131I. We suggest that the observed differences are due to the gradient of energy absorption in the follicular cell from irradiation from 125I stored in the colloid. The apical cytoplasm would absorb much more energy than the basal cytoplasm and the nucleus, in contrast to the uniform absorption of energy from 131I across the cell. The comparatively lower effect of 125I on goitrogenesis, and the paradoxical reduction in its effect in the low iodide diet groups, may be due to the low energy absorption by the nucleus, especially when, in a taller cell, the nucleus is farther from the colloid.

The applicability of a hapten-antihapten sandwich technique incorporating a monoclonal antihapten bridge antibody to localisation of tissue antigen is described. The results show that the method is both versatile and selective and has the potential of being even more sensitive than currently used immunoperoxidase methods.

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Publisher Summary This chapter discusses the role of 5-hydroxyindoles on thyroid gland. It presents a link between the morphology, histogenesis, and function of parafollicular cells with medullary carcinoma of the thyroid. It is suggested (1) that the lateral thyroid anlage plays a significant role in the development of the human thyroid, and that some of its derivatives persist throughout life; (2) that some cells from the lateral thyroid anlage give rise to the parafollicular system, which differs in morphology and function from the follicular. This cell system is able to concentrate 5-HTP and has a high content of 5-HT together with its enzymes of synthesis and degradation, 5-HTP decarboxylase and monoamine oxidase (MAO); (3) that medullary carcinoma of the thyroid is a tumor of parafollicular cells. It is associated with a clinical syndrome of watery diarrhea and may be associated with a raised 5-HIAA excretion; and (4) that the morphology, histogenesis, and function of medullary carcinoma distinguish it from other types of thyroid carcinoma.

The team of monitors was appointed as part of a settlementbetween CYFD, the state Human Services Department, and agroup of 14 foster children who sued the state. An experts' report found that New Mexico's child welfaresystem has housed foster kids in homeless shelters andother inappropriate settings, corroborating aninvestigation by ProPublica and Searchlight New Mexico. [Extracted from the article]

Papillary and follicular thyroid carcinomas show a different pattern of ras oncogene mutation

Teens in CYFD custody make up the majority of residents inchildren's crisis shelters across New Mexico, according tointerviews with shelter managers. New Mexico Is Putting Them in Homeless Shelters These Foster Kids Need Mental Health Care. Platero spent six months at the San Juan County shelter, right,while in CYFD custody. [Extracted from the article]

"We Know We Can Find Them Better Beds" The first residential treatment center in New Mexico to close, inearly 2019, was the state's largest: a 120-bed facility inAlbuquerque called Desert Hills that was the target of lawsuits andan investigation into physical and sexual abuse. Two and a half years after the state committed to reduce itsreliance on emergency placements, it continues to leave some of itsmost troubled teens without the mental health services they need. Several months before the New Mexico suit was filed, federallawmakers passed the Family First Prevention Services Act, whichredirected federal funding in order to pressure states into phasingout large residential treatment centers. [Extracted from the article]