Unusual Physiologic Melanin Pigmentation of the Tongue

A patient had extensive congenital oral hyperpigmentation of the tongue. The clinical and histologic features set this case apart from any well-delineated disease. Clinically, the congenital onset, the appearance of large black-brownish lesions, the lack of associated systemic abnormalities, and the histologic findings of prominent deposition of melanin in the basal layer support the diagnosis of physiologic melanosis. The macular lesions of the tongue represent discrete depositions of melanin and exemplify soft tissue pigmentation of developmental origin.     

Studies on the Level of Natural Antibodies Reactive with Various Tumor Cells during Urethane Carcinogenesis in BALB/c Mice

Serum from young normal BALB/c mice was found to contain IgM antibodies able tomediate complement-dependent lysis of certain syngeneic or allogeneic tumor target cells. The titer of such naturally occurring antitumor antibodies (NATA) was found to increase with aging.A longitudinal serological study comparing the cytotoxicity potential of NATA fromnormal and from urethan-treated BALB/c mice was performed. It was found that urethan-treated mice that did not develop primary lung-adenomas within the duration of the experi-ment had significantly lower NATA titers, against one out of 4 target cells assayed, than urethan-treated animals that developed lung adenomas. This difference was evident in two independent experiments. The results suggested that the lower NATA activity of the urethan-treated mice that did not develop tumors existed even before exposure to the carcinogenic insult. This raises the possibility that certain populations could be segregated according to their natural antibody profile into those individuals which will develop primary tumors within a certain period if exposed to a subthreshold amount of carcinogen, and those which will not.     

Linkage disequilibrium patterns of the human genome across populations

We studied the patterns of linkage disequilibrium (LD) in the human genome among three populations: African Americans, Caucasians and Ashkenazi Jews. These three populations represent admixed, outbred and isolated populations, respectively. The study examined defined chromosomal regions across the whole genome. We found that SNP allele frequencies are highly correlated between Ashkenazi Jews and Caucasians and somewhat distinct in African Americans. In addition, Ashkenazi Jews have a modest increase in LD compared with Caucasians, and both have greater LD than African Americans. The three populations differed more significantly with regard to haplotype heterogeneity. We found, as expected, that Ashkenazi Jews display the greatest extent of homogeneity and African Americans the greatest extent of heterogeneity. We found that most of the variance in LD can be attributed to the difference between regions and markers rather than to that between different population types. The average recombination rates estimated by low-resolution genetic maps can only explain a small fraction of the variance between regions. We found that LD (in terms of r(2)) decreases as a function of distance even within the so-called 'haplotype blocks'. This has significant consequences when using LD mapping for the genetic dissection of complex traits, as higher density SNP maps will be required to scan the genome.     

Women's post-chemotherapy parity is affected by offspring number and marital status

Childbearing rates post-chemotherapy for breast cancer (BC) are affected by age and chemotherapy-type but may also depend on personal characteristics. In this single institution retrospective study we evaluated post-chemotherapy fertility and its association with offspring number and marital-status at the time of BC diagnosis.We identified 65 fertile BC patients under 38y, who received adjuvant-chemotherapy. Menses resumption and pregnancies along with offspring-number and marital-status were recorded. Menses resumed in 95.4% and 33.8% gave birth. Of those who did not give birth 46.5% had at least three children at diagnosis and of those without children 83% were unmarried. Our data associates multiparity with lower childbearing post-chemotherapy, suggesting it as a possible surrogate for women's preferences in retrospective studies. Unlike multiparity, marital status association with lower childbearing may be culture-dependent and not a universal surrogate for women's intentions and would be best investigated prospectively.     

17 Beta-estradiol suppresses AMPA-induced increases in regional cerebral O2 consumption

We tested the hypothesis that 17 beta-estradiol would reduce the cerebral O2 consumption response resulting from glutamate receptor stimulation by alpha amino-3-hydroxy-5-methyl-isoxazole-4-propionate (AMPA). Fourteen ovariectomized rats were separated into 17 beta-estradiol (0.5 mg 21 day release pellet) and control (placebo pellet) groups to determine cerebral blood flow (14C-iodoantipyrine) and O2 consumption (microspectrophotometry). After topical cortical stimulation with 10(-3) M and 10(-4) M AMPA, cerebral blood flow increased significantly in both groups in a concentration-dependent manner. Cerebral O2 extraction was not significantly different in any region of the 17 beta-estradiol treated group. In the placebo treated group, the O2 extraction in the saline treated cortex and in the 10(-3) M AMPA treated cortex was significantly higher when compared to the 10(-4) M AMPA treated cortex. Cerebral O2 consumption in the control group increased by 20%, from 5.2 +/- 0.6 to 6.1 +/- 0.7, with 10(-4) M AMPA and significantly increased by 64% to 8.5 +/- 0.8 ml O2 min-1 100 g-1 with 10(-3) M AMPA. The 17 beta-estradiol group demonstrated no statistically significant difference in O2 consumption between the saline treated and AMPA treated cortex. Thus, 17 beta-estradiol reduced the effects of AMPA in increasing cerebral O2 consumption.     

DESIGN OF A PHOTOAFFINITY LABEL FOR THE HORMONE BINDING SITE OF NEUROPHYSIN

The photolabile peptide, L-methionyl-L-tyrosyl-p-azido-L-phenylalaninamide, was synthesized by solution methods. This peptide, as well as the analogous species containing tritiated methionine, were found to bind reversibly and specifically, in the dark, to bovine neurophysin II. The dissociation constant, stoichiometry, and pH-dependence of this noncovalent interaction are typical of those properties for hormone (oxytocin) and hormone-like ligand binding to neurophysin II. Under photolytic conditions, methionyl-tyrosyl-p-azidophenylalaninamide causes irreversible inhibition of the noncovalent ligand binding activity of neurophysin II. This inactivation was achieved to the extent of about 90%. Both the dark and light (photolytic) interactions of the photolabile peptide with neurophysin II indicate its reaction at the hormone binding site of the protein and thus its potential use to identify amino acid residues at this site by covalent photoaffinity labelling.     

Peritoneal cyst--a case report

Peritoneal cysts are rare benign tumors of the abdominal and pelvic peritoneum. We present a case of 26 year old patient with a peritoneal cyst treated operatively.     

Radiological features of glandular odontogenic cyst

OBJECTIVES: To present five new cases of glandular odontogenic cyst (GOC) and to review the radiological features at presentation as reported in the English literature. METHODS: From 1993 to 2002, five patients in our department were diagnosed with GOC based on histopathological findings and supported by radiography and CT. The radiographic features of the new GOC cases were analysed in addition to 51 literature cases. RESULTS: There were 31 male and 25 female patients, aged 14-90 years (mean 50 years). The mandible was involved in 80% and the maxilla in 20%; most of the lesions were located in the anterior jaw. Radiographically, 52% of the lesions were unilocular and 48% were multilocular; 94.5% showed well defined borders, which were sclerotic in 7.7% and scalloped in 13%. Information on cortical plate integrity was available in only 24 cases: 50% showed perforation, 8.3% erosion of the cortical plates and 8.3% thinning of the cortical plates. Root resorption was reported in 22% of patients and tooth displacement in 24.4%. CONCLUSIONS: Data collected indicate that GOC has potentially aggressive behaviour, with expansion and perforation in a significant number of cases. We recommend the use of multiple plane radiographs, with CT reserved for large lesions, especially those that are multilocular or involve extragnathic structures.     

The effect of neck dissection on human fat transport

This study examines the effect of neck dissection and thoracic duct ligation on lipid metabolism. Included were 23 patients undergoing neck dissection with thoracic duct ligation. The results showed a temporary reduction in lipid metabolism in approximately half the patients who had a left neck dissection. This effect subsided within 6 months, possibly because of the development of alternative lymph channels. The reduction in fat metabolism in selected cases may have therapeutic effects on patients with morbid hypertriglyceridemia or those who receive chemopreventive regimens. To the best of our knowledge, no similar studies have been reported heretofore in humans.