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Existing models of mouse mammary carcinogenesis induced by the model polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA) typically use a small number of bolus doses applied intragastrically. In contrast to this, typical human exposures to carcinogens are thought to be at lower doses and to occur with chronic or sporadic timing. When the classical dosage (1 mg DMBA given once a week for 6 weeks) was split into five daily doses of 200 microg given intragastrically to female SENCAR mice each week for 6 weeks, toxicity was high and the major tumor type seen was lymphoma. Lowering the dose to 60 microg/day gave less toxicity, a 75% incidence of lymphoma and a 30% incidence of mammary carcinoma. However, 20 microg DMBA given five times per week for 6 weeks resulted in a 65-70% incidence of mammary carcinoma within approximately 50 weeks. This represents a 50-fold lower daily dosage of DMBA than that used in the classical model. DNA was prepared from 10 mammary adenocarcinomas and 10 lymphomas and exons 1 and 2 of the H-ras1, K-ras and N-ras genes were sequenced using PCR techniques. Mutations altering codons 12 or 61 of one of the ras family genes were found in 4/10 mammary carcinomas and 5/10 lymphomas. Three mammary tumors exhibited codon 61 mutations, one in each of the genes studied, and a fourth tumor contained a codon 12 mutation in the K-ras gene. Among the lymphomas, two mutations in codon 12 of K-ras, one mutation in codon 61 of K-ras and two mutations in codon 61 of N-ras were also found. Each of the mutations could be interpreted as a G-->T or A-->T transversion. It is suggested that the high incidence of lymphoma at the higher, repetitive doses may be related to immunotoxicity. These low dose models of lymphomagenesis and mammary carcinogenesis should prove useful for tests of chemopreventive agents that target the initiation phase of carcinogenesis. [ABSTRACT FROM PUBLISHER]

Myelinated nerve fibres isolated from Wistar rats chronically exposed to 2,5-hexanedione (0.8 ml/kg/day, intraperitoneally) over a period of 20 days, were stained with lectin-horseradish peroxidase conjugates. The lectins with high affinity for terminal D-galactopyranosyl residues, Bandeiraea simplicifolia-B4 (BSA I-B4) and peanut agglutinin (PNA), showed glycoconjugates in the control nodes of Ranvier. In the treated animals, application of PNA-HRP caused weak reactivity to the node of Ranvier; digestion with sialidase prior to the application of PNA-HRP conjugate enhanced reactivity, thus revealing the presence of a sialoglycoprotein. The results indicate that glycoconjugates of the Ranvier node undergo a rearrangement during exposure to 2,5-hexanedione. In particular, neutral glycoproteins with terminal galactose are replaced by sialoglycoproteins. These findings are consistent with the proposed role of polysialic acid as a regulator of axonal behaviour during regeneration. [ABSTRACT FROM AUTHOR]

Azurite, a natural mineral pigment consisting of basic copper carbonate (2CuCO 3 ·Cu(OH) 2 ), is one of the Middle Ages' most common blue pigments. Why paintings originally coated with azurite appear blackened today remains debated. Using a non-invasive multi-analytical approach, the study analysed several unexpectedly black-appearing details (objects such as books or clothing such as veils, robes, or mantles) in Antoine de Lonhy's works. The aim was to investigate if the black colour was due to intentional iconographic reasons, incautious restoration work, or painting deterioration. The analytical results displayed the presence of the blue pigment azurite, therefore, the expected original colour of various areas should be blue. To shed light on the discussion regarding the blackening, several other Renaissance paintings with similar black details were analysed, all from the same period and geographic area as de Lonhy's works and conserved under identical conditions. The reasons why the blackening takes place are still unclear. However, the combined use of X-ray fluorescence spectrometry (XRF), UV-visible diffuse reflectance spectrophotometry with optical fibres (FORS), portable X-ray diffraction (XRD), and the elemental mapping based on the XRF data revealed that these blackened areas were originally painted with azurite, suggesting they were once blue. This finding significantly changes the overall appreciation of these artworks.

The identification of gemstones is an important topic in the field of cultural heritage, given their enormous value. Particularly, the most important precious stones, namely diamond, emerald, ruby and sapphire, are frequently subjected to counterfeit by substitution with objects of lesser value with similar appearance, colour or shape. While a gemmologist is able to recognise a counterfeit in most instances, more generally, it is not easy to do this without resorting to instrumental methods. In this work, the use of UV-visible diffuse reflectance spectrophotometry with optic fibres (FORS) is proposed as a fast and easy method for the preliminary identification of gemstones, alternative to the classical methods used by gemmologists or to Raman spectroscopy, which is by far the instrumental method with the best diagnostic potential, but it cannot be used in situations of problematic geometric hindrance. The possibilities and the limitations given by the FORS technique are critically discussed together with the spectral features of the most important gemstones. Finally, the application of chemometric pattern recognition methods is described for the treatment of large sets of spectral data deriving from gemstones identification.

Asthma is the most common chronic disease in childhood. Overweight and obesity are included among the comorbidities considered in patients with difficult-to-treat asthma, suggesting a specific phenotype of the disease. Therefore, the constant increase in obesity prevalence in children and adolescents raises concerns about the parallel increase of obesity-associated asthma. The possible correlation between obesity and asthma has been investigated over the last decade by different authors, who suggest a complex multifactorial relationship. Although the particular non-eosinophilic endotype of obesity-related asthma supports the concept that high body weight precedes asthma development, there is ongoing debate about the direct causality of these two entities. A number of mechanisms may be involved in asthma in combination with obesity disease in children, including reduced physical activity, abnormal ventilation, chronic systemic inflammation, hormonal influences, genetics and additional comorbidities, such as gastroesophageal reflux and dysfunctional breathing. The identification of the obesity-related asthma phenotype is crucial to initiate specific therapeutic management. Besides the cornerstones of asthma treatment, lifestyle should be optimized, with interventions aiming to promote physical exercise, healthy diet, and comorbidities. Future studies should clarify the exact association between asthma and obesity and the mechanisms underlying the pathogenesis of these two related conditions with the aim to define personalized therapeutic strategies for asthma management in this population.

Duplication of the pituitary gland (DPG)-plus syndrome is a very rare developmental disorder with few cases described in the literature and characterized by multiple midline and central nervous system malformations. The hypothalamus and hypophysis involvement may be clinically associated with endocrine abnormalities. A 5.9-year-old female child was admitted to our Clinic for premature thelarche and acceleration of growth. DPG-plus syndrome with paired infundibula and pituitary glands was diagnosed after birth, when she appeared small for gestational age and she presented with lingual hypoplasia, cleft palate, right choanal stenosis, nasopharyngeal teratoma, and facial dysmorphisms. Neuroimaging revealed a duplication of the infundibula, the pituitary gland, and the dens of the epistropheus despite surgical removal of a rhino-pharyngeal mass performed at the age of two months. An array-CGH revealed a 2p12 deletion. At our evaluation, bone age assessment resulted advanced and initial pubertal activation was confirmed by Gonadotropin-Releasing Hormone stimulation test. Hormonal suppression treatment was started with satisfactory results. This case shows that DPG-plus syndrome must be considered in presence of midline and craniofacial malformations and endocrinological evaluations should be performed for the prompt and appropriate management of pubertal anomalies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Prezioso, Petraroli, Bergonzani, Davino, Labate, Ormitti, Anghinoni, Sesenna and Esposito.)

Incidence of inflammatory bowel diseases (IBDs), including Crohn's disease (CD) and ulcerative colitis (UC), is increasing worldwide. Children with IBDs have a dysfunctional immune system and they are frequently treated with immunomodulating drugs and biological therapy, which significantly impair immune system functions and lead to an increased risk of infections. Vaccines are essential to prevent at least part of these infections and this explains why strict compliance to the immunization guidelines specifically prepared for IBD patients is strongly recommended. However, several factors might lead to insufficient immunization. In this paper, present knowledge on the use of vaccines in children with IBDs is discussed. Literature review showed that despite a lack of detailed quantification of the risk of infections in children with IBDs, these children might have infections more frequently than age-matched healthy subjects, and at least in some cases, these infections might be even more severe. Fortunately, most of these infections could be prevented when recommended schedules of immunization are carefully followed. Vaccines given to children with IBDs generally have adequate immunogenicity and safety. Attention must be paid to live attenuated vaccines that can be administered only to children without or with mild immune system function impairment. Vaccination of their caregivers is also recommended. Unfortunately, compliance to these recommendations is generally low and multidisciplinary educational programs to improve vaccination coverage must be planned, in order to protect children with IBD from vaccine-preventable diseases.

Aim: The therapeutic model for severe obesity includes bariatric surgery, representing the safest way to keep weight down and to prevent relapses. The selection of patients for the most suitable type of surgery implies multidisciplinary approach (nutritionist, dietist, clinical psychologist and surgeon). The intragastric balloon may represent a relatively invasive method to help the medical team to select and prepare severely obese patients for restrictive bariatric surgery., Methods: In our study we considered 48 severely obese patients: initial weight 111+/-14.8 kg, BMI 43+/-5.02, excess weight 77.47+/-16.14%. These patients have been treated with intragastric balloon (BIB) filled to a volume of 500 cc for 6 months. We considered variations induced by BIB treatment on a number of parameters--clinical, anthropometric, food intake, partition of nourishing elements and psychological and psychometric data., Results: At the end of the treatment the patients showed significant reductions of excess weight (67.35+/-20.19%), of weight (103.4+/-16.72 kg) and food intake, without modification of the items in the EDI2 test, but with important motivational support for a change in life style between the beginning and the end of the treatment, clearly resulting from the medical, dietist and clinical-psychological follow-up., Conclusions: BIB is a relatively invasive means capable of modifying eating habits in the short term; it induces weight loss, may help to reduce the anaesthesiological risk and to foster a change in the patient's behaviour. In our experience treatment with BIB is useful from the educational point of view and can be used to select patients for bariatric surgery only within a multidisciplinary team. Further clinical studies are necessary.

The paper reports a histological and immunohistochemical description of oocyte growth and ultrastructural aspects of zona radiata (ZR) formation as well as the relationship between plasma estradiol-17beta, (E2) levels and ovarian development in swordfish (Xiphias gladius L.) from the Mediterranean Sea. Ovaries were inactive during March to mid April; maturation occurred during late April to June and spawning in June and July. Zona radiata formation starts, as Pas positive material, in oocytes at the lipid stage. In this stage a deposit of electrondense material between oolemma and follicular cells appears. In the cortical alveoli stage and through the early vitellogenic stage, the deposition of a moderately electrondense material occurred on the inner side of the ZR. Finally, in late vitellogenic oocytes a third layer, made of microfibrillar material, appeared. The immunohistochemical analyses revealed that the initial internalisation of hepatic zona radiata proteins (Zrp) in the swordfish oocyte starts before the uptake of vitellogenin (Vtg) and that it is associated with the low previtellogenic E2 plasma levels, while a significant E2 increase in plasma is associated with the beginning of Vtg uptake. This would appear to confirm the hypothesis that the differential and sequential induction of zonagenesis and vitellogenesis may reflect a general feature of teleost oogenesis.

Screening of newly synthesized organic peroxides for tumor initiating/promoting activity would be greatly facilitated if predictive methodologies could be developed using topical exposures shorter than those required for definitive tumor assessment in mouse skin models. Nine organic peroxides [benzoyl peroxide (BZP), di-t-butyl peroxide (DTBP), t-butyl peroxybenzoate (TBPB), p-t-butyl isopropylbenzene hydroperoxide (TBIBHP), cumene hydroperoxide (CHP), dicetyl peroxydicarbonate (DPD), dicumyl peroxide (DCP), methyl ethyl ketone peroxide (MEKP) and O,O-t-butyl-O-(2-ethylhexyl) monoperoxycarbonate (TBEC)] were evaluated for their ability to increase biomarkers of tumor promotion in mouse skin, i.e. sustained epidermal hyperplasia, dermal inflammation and oxidative DNA damage. Evaluations were performed using SENCAR mice exposed topically for 4 weeks. The organic peroxides varied in their effects on these biomarkers. BZP, TBPB and TBIBHP exhibited significant increases in all three biomarkers associated with tumor promoting activity, CHP produced increases only in sustained epidermal hyperplasia and dermal inflammation, MEKP and DCP produced increases only in sustained epidermal hyperplasia and TBEC produced an increase only in dermal inflammation. DTBP and DPD had no effect on the three parameters studied. TBPB and TBIBHP were selected for further examination of their ability to produce mutations in codons 12, 13 and 61 of the c-Ha-ras protooncogene, i.e. those mutations known to be involved in the initiation of mouse skin tumors, because they were the only peroxides to exhibit significant positive results in all assays except the Ha-ras mutation following 4 weeks of exposure. Evaluations were performed using SENCAR mice dosed topically for 8 or 12 weeks in a complete carcinogenesis protocol or 16 weeks in an initiation/promotion protocol using 7,12-dimethylbenz[a]anthracene, urethane, benzo[a]pyrene and N-methyl-N'-nitro-N-nitrosoguanidine as positive controls. Neither TBPB nor TBIBHP produced detectable mutations in the c-Ha-ras protooncogene, indicating that they are not likely to possess tumor initiating or complete carcinogenic activity.

The regional difference in the carbohydrate components of the ductus epididymis epithelium of a lizard was delineated by means of 13 lectins. Basal cells expressed only N-acetylglucosamine (GlcNAc). Throughout the ductus, the secretory cells showed oligosaccharides with terminal N-acetylneuraminic acid (Neu5Ac)alpha(2,6)galactose (Gal)/N-acetylgalactosamine (GalNAc) and internal mannose (Man) and/or glucose (Glc) in the whole cytoplasm, oligosaccharides terminating in Neu5Ac alpha(2,6)Gal beta(1,3)GalNAc, Neu5Ac alpha(2,6)Gal beta(1,4)GlcNAc, GalNAc, GlcNAc, and fucose (Fuc) in the supra-nuclear zone, and also glycans terminating in Neu5Ac alpha(2,3)Gal beta(1,4)GlcNAc, Neu5Ac alpha(2,6)Gal beta(1,3)GalNAc, Gal beta(1,4)GlcNAc on the luminal surface. In the caput and corpus regions, the supra-nuclear cytoplasm was characterized by terminal Gal beta(1,4)GlcNAc and alphaGalNAc, the luminal surface by alphaGalNAc and Gal. The Golgi zone, showing oligosaccharides with terminal Neu5Ac alpha(2,3)Gal beta(1,4)GlcNAc, Neu5Ac alpha(2,6)Gal beta(1,3)GalNAc, Neu5Ac alpha(2,6)Gal beta(1,4)GlcNAc, and internal GlcNAc, expressed terminal Gal beta(1,4)GlcNAc and alphaGalNAc in the caput, and terminal betaGalNAc in the corpus. The granules showed all the investigated carbohydrates in their peripheral zone except terminal betaGalNAc and Fuc, whereas internal Man/Glc and terminal Gal were expressed in the central core, and Fuc throughout the ductus, terminal GlcNAc in the caput and corpus, and terminal alphaGalNAc only in the corpus.

The pars distalis from the pituitary gland of adult male ruin lizards (Podarcis sicula campestris De Betta), captured during the five periods of the annual sexual cycle (emergence from hibernation, reproductive period, summer regression, autumnal recrudescence, winter arrest), was studied immunohistochemically using specific antibodies against hFSHbeta, hLHbeta, oFSHbeta, and oLHbeta with the avidin-biotin complex (ABC) procedure to monitor the seasonal changes in shape, size and percentage area taken up from gonadotropes. FSH containing cells were specifically identified with anti-hFSHbeta and anti-oFSHbeta sera, whereas the LH cells were localized by anti-hLHbeta. The anti-oLHbeta serum showed cross-reactivity with the cells immunostained by the three above antisera (anti-hFSHbeta, anti-oFSHbeta, and anti-hLHbeta). None of the cells contained both gonadotropic hormones as shown by the double-immunostaining procedure. Generally, FSH cells were larger and more numerous than LH cells. FSH cells were elongated or pyriform in shape from spring to autumn, whereas they were round or oval during the winter stasis and until the emergence from hibernation. The size and the percentage area occupied by FSH cells showed an annual pattern with two distinct peaks in the reproductive and in the autumnal recrudescence periods. LH cells did not show seasonal changes in shape, being round or oval throughout the reproductive cycle, whereas their size and the area they occupied underwent seasonal variations. The LH cells reached the largest size during the reproductive period and the smallest size during the summer regression. The percentage area occupied by LH cells in the pars distalis peaked at the emergence from hibernation and during the summer refractory period, when FSH cells displayed their lowest values.

Purpose: This study was undertaken to establish the pattern of specific p53 gene mutations in prostate cancer within primary tumors and distant metastases., Materials and Methods: We performed polymerase chain reaction-single-strand conformation polymorphism and sequencing analyses of p53 exons 5-8 in DNA extracted from 22 formalin-fixed, paraffin-embedded tissues from 17 patients. Samples from three patients included specimens from primary and metastatic sites (paired specimens)., Results: G:C-to-A:T transitions were the most common point mutations (64%). Six (55%) of 11 G:C-to-A:T transitions occurred at CpG dinucleotides in five hot-spot codons (175, 245, 248, 273, and 282). Sequencing analysis of the paired samples revealed that two of the three pairs had the same mutation in both. Sequencing analysis of DNA from a different area of one of the primary tumors revealed a different mutation in the p53 gene., Conclusions: Our results suggest that specific p53 mutations participate in the progression of human prostate cancer. These findings support those of others that indicate that the primary cancer is heterogeneous and clonal expansion occurs during the progression of clinically detectable prostate cancer. Our data also imply that p53 mutations at the primary site may be predictive of metastases.

Malignant mesothelioma is one of the very few extrarenal neoplasms in which the Wilms tumor suppressor gene (wt1) is expressed. We examined wt1 for alterations in rat mesotheliomas, a well characterized animal model for the human disease. Southern analysis revealed a 3.5 kb EcoRI wt1 fragment readily detectable in majority of mesothelioma cell lines and primary mesotheliomas but not in normal rat tissues. Cloning and sequencing of this fragment revealed that the presence of this EcoRI fragment resulted from an inability of this enzyme to cut at a EcoRI site in intron 1 of wt1. This site contains potential motifs for cytosine methylation and treatment of mesothelioma cells with 5-azadeoxycytosine restored the normal EcoRI digestion pattern of wt1 in these cells indicating that cleavage was inhibited by methylation at this site. Southern analysis using HpaII/MspI digestion revealed no differences in methylation between mesothelioma cell lines and normal mesothelium at other CpG sites in wt1 5' region. Renal cell carcinoma lines which did not express wt1 were also methylated at this EcoRI site. Our identification of a site frequently methylated in malignant cells, independent of gene expression, provides a new model system to study determinants of site-specific methylation in tumors.

The pars distalis from the pituitary gland of adult male ruin lizards (Podarcis sicula campestris De Betta), captured during the reproductive period (May and June), was studied immunohistochemically using specific antibodies against hFSH beta, hLH beta and oLH beta with the avidin-biotin-peroxidase complex (ABC) procedure to determine the localization of both gonadotropins. The immunostaining with anti-hFSH beta and anti-hLH beta allowed identification of morphologically distinct FSH containing cells and LH containing cells, whereas anti-oLH beta serum showed cross-reactivity with cells immunostained with the anti-hFSH beta and anti-hLH beta sera. The gonadotropic cells took up approximatively 10.5% of the area of the pars distalis: 10% was positive for FSH, whereas only 0.5% was positive for LH. The FSH cells were distributed throughout the pars distalis, whereas the LH cells were only located in the rostral region. Double-immunostaining procedure did not reveal cells containing both gonadotropic hormones. The findings indicate that FSH and LH are produced in separate pituitary cells.

The epididymal ductuli efferentes of the lizard Podarcis sicula campestris De Betta are lined with simple, columnar, nonciliated and ciliated cells. The use of lectin histochemistry has provided information about changes of sugars associated with glycoconjugates of epithelial cells and intraluminal spermatozoa which are conveyed from the longitudinal canal to the cranial region of the ductus epididymis. Epithelial cells exhibited residues of alpha-D-mannose, N-acetylglucosamine, and beta-D-galactose-(1-4)-N-acetylglucosamine as revealed with lectins Con A, WGA and RCA120, respectively, throughout the sexual cycle. An increase of RCA120 staining was observed on microvilli of nonciliated cells and in the cytoplasm of ciliated cells during the reproductive period. However, during the following refractory period, when the organ was in regression, there was a decreased staining with Con A on microvilli and the absorbent surface of nonciliated cells, with WGA in nonciliated cells and the cytoplasm of ciliated cells, and with RCA120 on microvilli and the cytoplasm of both cell types. Terminal alpha-D-galactose residues were increasingly stained from autumn up to the reproductive period with BS I-B4 on microvilli, the absorbent surface and cilia, whereas they were entirely lacking during the refractory period. UEA I revealed alpha-L-fucose residues on the absorbent surface of nonciliated cells during the abortive and reproductive periods, increasing in the latter period when cilia also expressed this sugar. Terminal alpha/beta-D-N-acetylgalactosamine was evidenced with SBA on the absorbent surface of nonciliated cells during the reproductive period. The terminal beta-D-galactose-(1-3)-N-acetylgalactosamine dimer was never found with PNA, whereas O- and N-linked sialoglycoconjugates were present only during the reproductive period. The spermatozoa head exhibited N-linked glycans with high-mannose content, and beta-D-galactose-(1-4)-N-acetylglucosamine as well as O- and N-linked sialoglycoconjugates throughout the year. During the reproductive period, oligosaccharides with alpha-D-mannose residues increased, and oligosaccharides with terminal alpha-D-galactose, alpha-L-fucose and sialic acid-N-acetylgalactosamine dimer were also present. Unlike spermatozoa of seminiferous tubules, the spermatozoa head of the lizard epididymal ductuli efferentes exhibited seasonal variability in the lectin binding pattern which may be related to time-dependent changes in the glycoconjugate profiles of epithelial cells.

Chemical induction of mammary tumors in mice requires usually a long latency period and is often complicated by high non-mammary tumor related mortality. Classically hormone stimulation has been used as the means to increase tumor incidence. The synthetic progestin medroxyprogesterone acetate (MPA) was postulated by some authors to increase mammary tumor incidence in various rodent models. However, controversy exists regarding the role of MPA in experimental and human carcinogenesis. In our study we tested the use of a protocol of combined MPA- and dimethylbenz[a]anthracene (DMBA) treatment for the obtention of mammary tumors with a short latency and with a lower toxicity than the classical multiple dose DMBA protocol. MPA was very effective in accelerating the development and increasing the incidence of mammary tumors induced by DMBA in CD2F1 mice. MPA by itself did not produce any mammary tumors. The mean latency for tumor development from the end of carcinogen treatment was 99 +/- 51 days in the group that received a combination of MPA and four DMBA doses. This group showed significantly earlier mammary tumor incidence (P < 0.0001) and higher tumor numbers than the groups that received only DMBA. Mammary tumors were also analyzed for effects on the mutation rate affecting the Ha-ras and Ki-ras genes. Our data is consistent with MPA probably increasing the number of target cells at risk for mutation by the chemical carcinogen DMBA and possibly promoting the faster development of tumors.

A previously published method for predicting the frequency of random occurrence of a completely specified DNA oligomer in a longer sequence dataset has been generalized to allow degeneracy in the oligomer sequence. With this enhancement, several datasets consisting of sequences from the human genome were searched for the occurrence of consensus binding sites for a set of 13 transcription factors. Although because of the biological significance of these sequences one might predict that they would occur more often than the random frequency, many of the consensus oligomers were found at lower than expected frequencies. Several (G+C)-rich oligomers were found to be moderately over-represented, but this could be accounted for, in part, by the occurrence of (G+C)-rich tracts in the human sequences. Regions very high in (G+C) were found to occur at much higher frequencies than expected in the human genome, and this severely limits the usefulness of this approach for predicting the frequency of (G+C)-rich oligomers. Unexpectedly, more than 1% of the human genome consists of tracts at least 28 bp in length with a (G+C) content greater than 85%.

To confirm that the hamster cheek-pouch carcinogenesis model reflects development of human squamous cell carcinoma (SCC), we determined if and when p53 mutations occur in the development of SCC in this model by using immunohistochemical staining and polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) analysis plus direct DNA sequencing. Twenty-four hamster cheek-pouches were treated with a solution of 0.5% 7,12-dimethylbenz[a]anthracene in mineral oil three times a week for 16 wk. The malignant endophytic and exophytic tumors induced with this protocol are preceded by a sequence of premalignant lesions such as hyperplasia with or without dysplasia and carcinoma in situ, similar to the development of this cancer in humans. For this study, p53 protein accumulation was evaluated by immunostaining of various hamster cheek-pouch exophytic and endophytic SCCs as well as flat dysplastic hyperplasia and carcinomas in situ. A moderate percentage (33.3%) of exophytic lesions and most endophytic carcinomas (90%) showed positive p53 staining. In addition we also found p53-positive staining in a number of preneoplastic lesions, including areas of focal hyperplasia, dysplastic hyperplasia, and carcinomas in situ. To determine whether the alterations in p53 staining were due to p53 gene mutation, we used PCR-SSCP analysis and direct sequencing. PCR products corresponding to exons 5a, 6, 7, and 8 from 40 tumors with the highest percentage of p53-stained cells were analyzed. We detected shifted bands in 17 lesions. Direct sequencing of eight selected shifted bands revealed four mutations, including two G-->T transversions in codons 216 (tumor #1) and 252 (tumor #2) and one G-->C transversion in codon 282 (tumor #3). Tumor #4 contained a frameshift mutation in codon 251. These mutations are consistent with those reported in many human cancers. Therefore, we concluded that in the hamster cheek-pouch model, p53 protein accumulation occurs frequently and early in carcinogenesis, as it does in human SCCs, and some of these p53 alterations are due to p53 gene mutations. These findings may help us better define the mechanisms of carcinogenesis in the hamster cheek-pouch model, and p53 alterations may be an early biomarker of progression for chemoprevention studies.

The distribution of glycoconjugates in the testis of lizard Podarcis s. campestris De Betta was investigated by HRP-conjugated lectins during the annual spermatogenetic cycle. In addition, pretreatments of sections with neuraminidase and removal of alkali-labile O-linked sequences by beta-elimination allowed the structure of glycoconjugates to be further explored. Leydig cells displayed changes of lectin-binding sites during annual cycle, and during the abortive spermatogenesis period lacked N-linked sialylgalactosyl glycans. Sertoli cells stained by Con A, WGA, RCA120, BS I-B4, showed, except in July, O-linked sialylgalactosyl glycans. Spermatogonia bound Con A and WGA. Spermatocytes bound also BS I-B4, SBA, UEA I, and during spring spermatogenesis, revealed O-linked sialylgalactosyl glycans. The acrosomes of spermatids were also stained by RCA120 and PNA, whereas the heads of spermatozoa did not bind SBA and PNA. During the abortive spermatogenic period, the acrosomes showed O-linked sialylgalactosyl glycans and N-linked glycans terminating in beta-galactosyl residues. During the reproductive period, the acrosomes of spermatozoa expressed O- and N-linked sialylgalactosyl glycans and beta-galactosyl terminal residues on O- and N-linked glycans. This, in the testis of lizard, the two spermatogenesis periods show the emergence of different types of glycosylation.

Knowledge of the incidence of haemodynamic imbalance syndromes and consequent pathologies in growing children at various ages may be a useful aid to the preventive measures that make for effective treatment of the organs involved in the psychological and physical development of school children. The oscillation between haemodynamic balance and imbalance was monitored in 849 subjects aged 3-18 on the basis of periods of absence relatable to the biorhytmic cycle of each pupil within the daily and seasonable rhythm. The survey identifies the instruments that facilitate natural haemodynamic balance and reduce desynchronising stimuli.

In 25 heroin addicts examined an initial alteration in microcirculatory homeostasis was found ond held to be responsible for the addiction. As in other cases it is thought possible to use the chronobiological course of haemodynamic balance and imbalance as a biological marker for prevention and treatment.

The annual sequence of sickness leaves was studied in 162 industrial workers with a high absenteeism level. An investigation of the swings in haemodynamic balance, and imbalances linked to alternations in vessel constriction and dilation throughout the biorhythmic cycle influenced by the alternation of night and day, hot and cold seasons, showed that each period of sick leave coincided with each period of haemodynamic balance caused by particular shifts. It was thus possible to identify groups of workers with syndromic sub groups whose performance was affected by night work and particular seasons. For optimal shift-worker deployment it is therefore suggested that workers should be assigned to shifts to which they are biologically suited.

GAP-43 (a.k.a. B-50, F1, pp46, or neuromodulin) is a major growth cone membrane protein whose expression is widely correlated with successful axon elongation, but whose function remains unknown. To distinguish the structural features of GAP-43 most relevant to its cellular functions, we have determined features of the protein that are most highly conserved in vertebrate evolution. Comparison of fish and mammalian GAP-43 distinguishes two domains of the protein. A strictly conserved amino-terminal domain contains the putative site for fatty acylation and membrane attachment, a calmodulin binding domain, and a proposed phosphorylation site. In the much larger carboxy-terminal domain, amino acid composition is strongly conserved without extensive sequence conservation. This amino acid composition predicts an extended, negatively charged rod conformation with some similarity to the side arms of neurofilaments. The results suggest that the biological roles of GAP-43 may depend on an ability to form a dynamic membrane-cytoskeleton-calmodulin complex.

The compounds 3-hydroxy-3-methylglutaric acid (HMG) and HMG diethylester were administered to laying Coturnix hens to evaluate their potential in reducing yolk cholesterol concentrations. The administration of HMG did not produce consistent differences from controls in tissue levels of either cholesterol or triglycerides. The administration of HMG diethylester appeared to increase the de novo synthesis of cholesterol and the mobilization of cholesterol from liver to serum, as assayed by the uptake and conversion of [1-14C]acetate into 14C-cholesterol. Neither HMG diethylester nor HMG significantly decreased the amount of cholesterol deposited in egg yolk.

Studies were undertaken to determine the effect of inhibitors of cholesterol synthesis on deposition of cholesterol in eggs of Japanese quail. Results indicate that this bird responds similarly to the laying hen, making it a useful screening device for these types of compounds. Administration of either triparanol or 20,25 diazacholesterol resulted in a decreased cholesterol content of the yolk. Concomitant with this decrease was an increase in desmosterol deposition. Beta sitosterol (2%) fed either alone or with lecithin (2%) did not result in a decrease in egg yolk cholesterol. No beta-sitosterol was found in the egg yolk. Diazacholesterol fed either with sitosterol, or sitosterol plus lecithin, was not effective in reducing the total sterol content of egg.

Estradiol transiently increases the rate of peptide elongation on uterine ribosomes from ovariectomized mature rats during the first 2 h after hormone injection, suggesting the existence of direct or indirect estradiol receptor interaction with ribosomes. Characterization of estradiol-binding components on isolated uterine ribosomes, microsomes, and cytosol under identical assay conditions indicated that microsomes and cytosol contain estradiol-binding components with similar affinities for estradiol (Kd = 0.5 nM) and sucrose gradient sedimentation characteristics (3.8S and 5.2S for preparations incubated at 0 and 30 C for 1 h, respectively). Those on ribosomes exhibited a higher affinity for estradiol (Kd = 0.14 nM) and had heterogeneous and more dense sedimentation characteristics (5.5-6.0S). The ribosome-associated estradiol binder was clearly different from transformed cytosol and nuclear estradiol receptors based on sedimentation characteristics under identical conditions. Like cytosol and nuclear receptors, microsomal and ribosomal estradiol binding underwent exchange reactions in vitro at 30 C, but not at 0 C. All in vitro bound, but not all in vivo bound, [3H] estradiol could be exchanged from microsomes or ribosomes by estradiol. [3H]Estradiol could be exchanged from ribosomes by a variety of estrogens, but not by progestins, glucocorticoids, or androgens. The amount of estradiol-binding activity on ribosomes decreased after estradiol administration in vivo and was inversely correlated with the rate of peptide elongation by the ribosomes in a cell-free protein synthesis system. These results suggest that accumulation of an estradiol-binding protein, perhaps a nascent estradiol receptor, on ribosomes in the absence of in vivo estradiol may directly or indirectly inhibit the peptide elongation reaction.