Mutations in a novel gene lead to kidney tumors, lung wall defects, and benign tumors of the hair follicle in patients with the Birt-Hogg-Dubé syndrome

Birt-Hogg-Dubé (BHD) syndrome is a rare inherited genodermatosis characterized by hair follicle hamartomas, kidney tumors, and spontaneous pneumothorax. Recombination mapping in BHD families delineated the susceptibility locus to 700 kb on chromosome 17p11.2. Protein-truncating mutations were identified in a novel candidate gene in a panel of BHD families, with a 44% frequency of insertion/deletion mutations within a hypermutable C(8) tract. Tissue expression of the 3.8 kb transcript was widespread, including kidney, lung, and skin. The full-length BHD sequence predicted a novel protein, folliculin, that was highly conserved across species. Discovery of disease-causing mutations in BHD, a novel kidney cancer gene associated with renal oncocytoma or chromophobe renal cancer, will contribute to understanding the role of folliculin in pathways common to skin, lung, and kidney development.

Risk of renal and colonic neoplasms and spontaneous pneumothorax in the Birt-Hogg-Dubé syndrome

The Birt-Hogg-Dubé syndrome, a genodermatosis characterized by benign tumors of the hair follicle, has been associated with renal and colonic neoplasms and spontaneous pneumothorax, but the risk of developing these disorders is unknown. We identified risk factors for renal tumors and spontaneous pneumothorax in 98 patients affected with the Birt-Hogg-Dubé syndrome, in 13 Birt-Hogg-Dubé haplotype carriers, and in 112 unaffected family members. Development of renal tumors was strongly associated with the Birt-Hogg-Dubé syndrome and age. The odds ratio for renal tumor in BHD-affected family members adjusted for age was 6.9 (95% confidence interval, 1.5-31.6) and approximately 9.0 for the other risk factors considered. Chromophobe renal carcinoma, an uncommon type of renal cancer, was the predominant type of renal cancer found. Spontaneous pneumothorax was also strongly associated with the Birt-Hogg-Dubé syndrome and age. The odds ratio for pneumothorax in BHD-affected individuals, adjusted for age, was 50.3 (95% confidence interval, 6.4-392), and about 32 times higher adjusting for the other risk variables. Colon cancer and colon polyps were not related to the Birt-Hogg-Dubé syndrome. The Birt-Hogg-Dubé syndrome confers an increased risk for the development of renal tumors and spontaneous pneumothorax. We found no increase in risk for the development of colon polyps or colon carcinomas.

An intronic polymorphism of the hMLH1 gene contributes toward incomplete genetic testing for HNPCC

Hereditary non-polyposis colorectal cancer (HNPCC) is a common hereditary cancer. Genetic testing is complicated by the multiple DNA mismatch repair genes that underlie the disorder. Many suspected HNPCC families have no germ-line mutation identified. We reassessed an unusual family that appeared to have 2 individuals homozygous for a germline mutation within exon 1 of the hMLH1 gene. A few rare individuals with two inherited mutations in one of the mismatch repair genes have been reported and appear to have a distinct clinical appearance. However, there were no clinical features in the family discussed here that were consistent with constitutive lack of hMLH1. Redesigning the intronic primers for exon 1 identified a common polymorphism located within the original intronic primer site. The polymorphism prevented amplification of the wild-type allele, giving the erroneous appearance of homozygous inheritance of the mutated allele. Likewise, common intronic polymorphisms, if located within primer sequences on the chromosome harboring the HNPCC germ-line mutation could restrict amplification to only the wild-type allele, which may contribute significantly to the low success rate of identifying mutations in HNPCC families.

Mammographic densities as a marker of human breast cancer risk and their use in chemoprevention

Differences in the parenchymal pattern of the breast on mammography reflect differences in the amounts of stromal, epithelial, and fat tissue present in the breast. Stroma and epithelium are radiologically dense, whereas fat is lucent. Extensive areas of mammographically dense breast tissue are strongly associated with an increased risk of breast cancer. A variety of interventions, including gonadotropin-releasing hormone inhibitor, tamoxifen, stopping hormone replacement therapy (HRT), and adopting a low-fat, high-carbohydrate diet, all influence the tissue composition of the breast and reduce mammographic densities. Of the interventions examined to date, only tamoxifen has been shown to reduce the incidence of breast cancer, at least in the short term. Conversely, HRT, which increases density, also increases risk of breast cancer. These results suggest that mammographic density may be a short-term marker of the effect on the breast of potential preventive interventions for breast cancer.

Individual variation in the growth of captive infant gorillas

Serial anthropometric data were obtained during the first year of life of six nursery-reared infant gorillas in the Columbus (Ohio) Zoo. Two of the infants are likely to be monozygotic twins as determined by DNA analysis. Growth curves were fitted to serial measures of cephalo-thoracic-abdominal length, arm length, leg length, head circumference, upper arm circumference, and weight from each gorilla, to describe individual patterns of variation in skeletal growth and body composition. Growth in skeletal measures tended to be curvilinear to varying degrees over the first year of life. Body composition varied more than skeletal measures throughout the first year as a consequence of individual health status. Individual growth and body composition variations appear to reflect both genetic and environmental influences in this small sample of captive infant gorillas.

Plasma D-dimer levels in operable breast cancer patients correlate with clinical stage and axillary lymph node status

PURPOSE

To investigate the relationship between preoperative plasma D-dimer levels and extent of tumor involvement in operable breast cancer patients.

PATIENTS AND METHODS

A total of 140 preoperative plasma specimens were obtained from women scheduled to undergo diagnostic breast biopsies. Ninety-five patients in the initial group went on to undergo axillary lymph node dissection. Of the 140 patients from whom plasma samples were obtained, 102 were subsequently diagnosed with invasive breast carcinoma, nine were subsequently diagnosed with ductal carcinoma-in-situ, and 20 were subsequently diagnosed with benign breast disease. Plasma D-dimer levels were quantitated using a commercially available immunoassay kit (DIMERTEST; American Diagnostica, Greenwich, CT). The relationships between plasma D-dimer and other prognostic variables (tumor size, estrogen receptor, progesterone receptor, nuclear grade, histologic grade, lymphovascular invasion, and clinical stage grouping) were then examined using univariate and multivariate linear and logistic regression analyses.

RESULTS

Median plasma D-dimer levels were significantly higher in patients with invasive carcinoma than those patients with either benign breast disease or carcinoma-in-situ (P =.0001). A significant relationship existed between the presence of elevated D-dimer (> 100 ng/mL) and involved axillary lymph nodes (chi(2) test; P =.001). Elevated D-dimer levels predicted positive lymph node involvement in both univariate regression (P =.0035) and multivariate linear regression (P =.012) models. In addition, elevated D-dimer levels predicted the presence of lymphovascular invasion in univariate logistic regression (P =. 0025) and multivariate logistic regression analysis (P =.0053). Quantitative D-dimer levels were highly correlated with clinical stage grouping (analysis of variance test; P =.002).

CONCLUSION

Plasma D-dimer levels were markers of lymphovascular invasion, clinical stage, and lymph node involvement in operable breast cancer. This correlation suggests that detectable fibrin degradation, as measured by plasma D-dimer, is a clinically important marker for lymphovascular invasion and early tumor metastasis in operable breast cancer.

Trimethylaminuria is caused by mutations of the FMO3 gene in a North American cohort

Trimethylaminuria (TMAuria) (McKusick 602079) first described in 1970 is an autosomal recessive condition caused by a partial or total incapacity to catalyze the N-oxygenation of the odorous compound trimethylamine (TMA). The result is a severe body odor and associated psychosocial conditions. This inborn error of metabolism, previously thought to be rare, is now being increasingly detected in severe and milder presentations. Mutations of a phase 1 detoxicating gene, flavin-containing monooxygenase 3 (FMO3), have been shown to cause TMAuria. Herein we describe a cohort of individuals ascertained in North America with severe TMAuria, defined by a reduction of TMA oxidation below 50% of normal with genotype-phenotype correlations. We detected four new FMO3 mutations; two were missense (A52T and R387L), one was nonsense (E314X). The fourth allele is apparently composed of two relatively common polymorphisms (K158-G308) found in the general population. On the basis of this study we conclude that one common mutation and an increasing number of private mutations in individuals of different ethnic origins cause TMAuria in this cohort.

Oral Language Development in a Child With Floating-Harbor Syndrome

This clinical exchange presents a 3-year case study of oral language skill development in a child with Floating-Harbor syndrome (FHS). FHS is a rare condition that is characterized by short stature, expressive language delay, and triangular facies. Oral language skills were developed in the context of a naturalistic language intervention approach, within an early childhood schoolbased program. Initial presenting speech and language characteristics, as well as long-term needs, are discussed.

PFA-100 system: a new method for assessment of platelet dysfunction

The PFA-100 system is a platelet function analyzer designed to measure platelet-related primary hemostasis. The instrument uses two disposable cartridges: a collagen/epinephrine (CEPI) and a collagen/ADP (CADP) cartridge. Previous experience has shown that CEPI cartridges detect qualitative platelet defects, including acetylsalicylic acid (ASA)-induced abnormalities, while CADP cartridges detect only thrombocytopathies and not ASA use. In this seven-center trial, 206 healthy subjects and 176 persons with various platelet-related defects, including 127 ASA users, were studied. The platelet function status was determined by a platelet function test panel. Comparisons were made as to how well the defects were identified by the PFA-100 system and by platelet aggregometry. The reference intervals for both cartridges, testing the 206 healthy subjects, were similar to values described in smaller studies in the literature [mean closure time (CT) 132 s for CEPI and 93 s for CADP]. The use of different lot numbers of cartridges or duplicate versus singleton testing revealed no differences. Compared with the platelet function status, the PFA-100 system had a clinical sensitivity of 94.9% and a specificity of 88.8%. For aggregometry, a sensitivity of 94.3% and a specificity of 88.3% were obtained. These values are based on all 382 specimens. A separate analysis of sensitivity by type of platelet defect, ASA use versus congenital thrombocytopathies, revealed for the PFA-100 system a 94.5% sensitivity in identifying ASA users and a 95.9% sensitivity in identifying the other defects. For aggregometry, the values were 100% for ASA users and 79.6% for congenital defects. Analysis of concordance between the PFA-100 system and aggregometry revealed no difference in clinical sensitivity and specificity between the systems (p > 0.9999). The overall agreement was 87.5%, with a Kappa index of 0.751. The two tests are thus equivalent in their ability to identify normal and abnormal platelet defects. Testing 126 subjects who took 325 mg ASA revealed that the PFA-100 system (CEPI) was able to detect 71.7% of ASA-induced defects with a positive predictive value of 97.8%. The overall clinical accuracy of the system, calculated from the area under the ROC curve, was 0.977. The data suggest that the PFA-100 system is highly accurate in discriminating normal from abnormal platelet function. The ease of operation of the instrument makes it a useful tool to use in screening patients for platelet-related hemostasis defects.

Psychological support to an autologous bone marrow transplant unit in a community hospital: a pilot experience

Autologous Bone Marrow Transplantation (AuBMT) has emerged as an efficacious treatment for certain hematological and solid tumors. Some of the complications of allogeneic transplants are avoided with an autologous transplant. Due to the decreased toxicity of this procedure, AuBMT can be administered at a community hospital where the setting is less burdensome for patients and families. The latter can continue to provide support for the patient as relocation is not necessary and visiting is easier. This report is a case analysis of the first 30 patients to undergo an autologous transplant as a pilot study in such an environment. This pilot project--done in a community hospital in Connecticut--may provide cost effective, high quality care in a more personal environment in the patient's own community. The different neoplastic diagnoses are listed as well as the types of psychological interventions available for these patients. Two case studies are described for clinical illustration. A discussion presents how psycho-oncology can assist the multidisciplinary team.

Assessment of a food frequency questionnaire as a screening tool for low fat intakes

This study tested the ability of a self-administered food frequency questionnaire (FFQ) to identify women with low fat intakes. FFQs were completed by 95 control participants of a dietary trial at a mean 2.9 +/- 0.8 years post-randomization. Subjects were selected in approximately equal numbers from women who were low-fat eaters (< or = 30% of energy from fat) and high-fat eaters (> 30% of energy from fat). Percentage energy from fat derived from food records and FFQ were similar in both the low- and high-fat eaters. Percentage of energy from carbohydrate and total grams of carbohydrate (low-fat eaters only) were slightly higher measured by FFQ than by food records, and percentage of energy from protein was slightly lower. The correlation between nutrient intake measured by FFQ and food records for the whole group was 0.74 for percentage of energy from fat, 0.50 for total fat, 0.59 for percentage of energy from carbohydrate, 0.43 for total carbohydrate, 0.53 for percentage of energy from protein, 0.27 for total protein, and 0.32 for energy intake. Correlations were slightly lower when the low- and high-fat eaters were examined separately. The area under the receiver operating characteristic (ROC) curve, 0.83, was significantly above 0.5 (p < < 0.001), indicating that the FFQ discriminated between low- and high-fat eaters significantly better than chance. The FFQ cutoff point of 30% of energy from fat had a true positive rate of 0.63 and false positive rate of 0.24. The use of this cutoff point for screening would result in the loss of 36% of potential subjects and an estimated increase in baseline percentage of energy from fat intake of 2.3 percentage points.

Effects at two years of a low-fat, high-carbohydrate diet on radiologic features of the breast: results from a randomized trial. Canadian Diet and Breast Cancer Prevention Study Group

BACKGROUND

The appearance of breast tissue on mammography varies according to its composition. Fat is radiolucent and appears dark on mammography, while stromal and epithelial tissue has greater optical density and appears light. Extensive areas of radiologically dense breast tissue seen on mammography are associated with an increased risk of breast cancer.

PURPOSE

The purpose of the present study was to determine whether the adoption of a low-fat, high-carbohydrate diet for 2 years would reduce breast density.

METHODS

Women with radiologic densities in more than 50% of the breast area on mammography were recruited and randomly allocated to an intervention group taught to reduce intake of dietary fat (mean, 21% of calories) and increase complex carbohydrate (mean, 61% of calories) or to a control group (mean, 32% of calories from fat and 50% of calories from carbohydrates). Mammographic images from 817 subjects were taken at baseline and compared with those taken 2 years after random allocation by use of a quantitative image analysis system, without knowledge of the dietary group of the subjects or of the sequence in which pairs of images had been taken. The effects of the intervention on the mammographic features of breast area, area of dense tissues in the breast, and the percent of the breast occupied by dense tissue were examined using t tests. Multiple regression was used to examine these effects while accounting for age at trial entry, weight change, and menopausal status.

RESULTS

After 2 years, the total area of the breast was reduced by an average of 233.7 mm2 (2.4%) (95% confidence interval [CI] = 106.9-360.6) in the intervention group compared with an average increase of 26.3 mm2 (0.3%) (95% CI = -108.0-160.5) in the control group (P = .01). The area of density was reduced by 374.4 mm2 (6.1%) (95% CI = 235.1-513.8) in the intervention group compared with an average of 127.7 mm2 (2.1%) (95% CI = 8.6-246.7) in the control group (P = .01). Weight loss was associated with a reduction in breast area. The effect of the intervention on breast area was only marginally statistically significant after weight change, menopausal status, and age at trial entry were taken into account (P = .06). Greater weight loss and becoming postmenopausal were associated with statistically significant reductions in the area of density on the mammographic image at 2 years (P = .04 and P<.001, respectively). Age at entry into the trial was marginally significant in the same direction (P = .06). The effect of the intervention on area of density remained statistically significant after controlling for weight loss, age at entry, and menopausal status (P = .03). The change in the percentage of dense tissue in the mammographic image was not significantly different between the two groups (P = .71).

CONCLUSIONS AND IMPLICATIONS

These results show that after 2 years, a low-fat, high-carbohydrate diet reduced the area of mammographic density, a radiographic feature of the breast that is a risk factor for breast cancer. Longer observation of a larger number of subjects will be required to determine whether these effects are associated with changes in risk of breast cancer.

Somatic and gonadal mosaicism of the Huntington disease gene CAG repeat in brain and sperm

Huntington disease is associated with an unstable and expanded (CAG) trinucleotide repeat. We have analysed the CAG expansion in different tissues from 12 affected individuals. All tissues examined were found to display some repeat mosaicism, with the greatest levels detected in brain and sperm. Regions within the brain showing most obvious neuropathology, such as the basal ganglia and the cerebral cortex, displayed the greatest mosaicism, whereas the cerebellar cortex, which is seldom involved, displayed the lowest degree of CAG instability. In two cases of childhood onset disease we detected differences of 8 and 13 trinucleotides between the cerebellum and other regions of the brain. Our results provide evidence for tissue specific instability of the CAG repeat, with the largest CAG repeat lengths in affected regions of the brain.

Molecular analysis of juvenile Huntington disease: the major influence on (CAG)n repeat length is the sex of the affected parent

Juvenile Huntington disease (HD), characterised by onset of symptoms before the age of 20 with rigidity and intellectual decline, is associated with a predominance of affected fathers. In order to investigate the molecular basis for the observed parental effect, we have analysed the CAG trinucleotide repeat within the HD gene in 42 juvenile onset cases from 34 families. A highly significant correlation was found between the repeat length and age of onset (r = -0.86, p < 10(-7) and it was determined that the sex of transmitting parent was the major influence on CAG expansion leading to earlier onset. Neither the size of the parental upper allele, the age of parent at conception of juvenile onset child, nor the grandparental sex conferred a significant effect upon expansion. Affected sib pair analysis of CAG repeat length, however, revealed a high correlation (r = 0.91, p < 10(-7). Furthermore, analysis of nuclear and extended families showed a familial predisposition to juvenile onset disease. This study demonstrates that the sex of transmitting parent is the major influence on trinucleotide expansion and clinical features in juvenile Huntington disease.

Interscalene block for shoulder arthroscopy: comparison with general anesthesia

Arthroscopic shoulder surgery can be performed under regional or general anesthesia. The objective of this study was to demonstrate that regional anesthesia has several benefits over general anesthesia for this type of surgery, particularly in the ambulatory patient. Forty patients received general anesthesia and 63 an interscalene block. The regional block was found to be safe and effective, with a high degree of patient acceptance. It provided excellent intraoperative analgesia and muscle relaxation. Postoperatively, regional anesthesia resulted in fewer side effects, fewer hospital admissions, and a shorter hospital stay than did general anesthesia.

Replacement of arginine 773 by cysteine or histidine in the human androgen receptor causes complete androgen insensitivity with different receptor phenotypes

We have discovered two different point mutations in a single codon of the X-linked androgen-receptor (AR) gene in two pairs of unrelated families who have complete androgen insensitivity (resistance) associated with different AR phenotypes in their genital skin fibroblasts. One mutation is a C-to-T transition at a CpG sequence near the 5' terminus of exon 6; it changes the sense of codon 773 from arginine to cysteine, ablates specific androgen-binding activity at 37 degrees C, and eliminates a unique KpnI site at the intron-exon boundary. The other mutation is a G-to-A transition that changes amino acid 773 to histidine and eliminates an SphI site. This mutant AR has a normal androgen-binding capacity at 37 degrees C but has a reduced affinity for androgens and is thermolabile in their presence. Transient transfection of COS cells with cDNA expression vectors yielded little androgen-binding activity at 37 degrees C from Arg773Cys and abundant activity with abnormal properties from Arg773His, thereby providing the pathogenicity of both sequence alterations. This conclusion coincides with the following facts about evolutionary preservation of the position homologous to Arg773 in the AR: it is occupied by Arg or lysine in the progesterone, glucocorticoid, and mineralocorticoid receptors, and it is within a 14-amino-acid region of their steroid-binding domains that share approximately 85% amino acid identity.

The Emergence of Extended Metropolitan Regions in ASEAN: Towards the Year 2000

"This article analyses the growth of large Extended Metropolitan Regions in the Association of South East Asian Nations (ASEAN) in the period since 1960. The analysis reveals two trends. First, urbanization levels in ASEAN countries are rapidly increasing. By the year 2000, almost 40 per cent of the population will be urban residents. Second, these accelerating processes are creating giant urban regions, called Extended Metropolitan Regions. Analysis of demographic patterns of the emergence of the major urban regions of ASEAN...reveals that these are major areas of economic growth, with industrialization, building development and leisure activities fuelling this process. However, this rapid growth is causing major problems of urban infrastructure provision, land use conflict and environmental deterioration."

Cutaneous larva migrans due to Pelodera strongyloides

A twenty-year-old landscape worker was evaluated for a widespread cutaneous eruption consisting of papules, pustules, and burrows. Cutaneous scrapings revealed live and dead larvae of a free-living soil nematode, Pelodera strongyloides. This is the third instance of human dermatitis due to this organism, and the first reported in an adult host.

Superficial migratory thrombophlebitis and the lupus anticoagulant

The lupus anticoagulant is an antiphospholipid antibody found in association with systemic lupus erythematosus and in a variety of other diseases, as well as in healthy individuals. In the laboratory, the antibody interferes with the conversion of prothrombin to thrombin and prolongs the partial thromboplastin time. In vivo, it exerts a procoagulant effect resulting in thrombosis, mainly of the larger veins and arteries. The case of a young woman who developed superficial migratory thrombophlebitis in association with a high titer lupus anticoagulant is presented. Her diagnosis was initially missed because the partial thromboplastin time was not elevated. This appears to have resulted from the use of a specific thromboplastin relatively insensitive to the presence of the antibody. Retesting with a more sensitive reagent showed a markedly prolonged partial thromboplastin time.

Preoperative assessment of fragment D-dimer as a predictor of postoperative venous thrombosis

We used a latex agglutination assay to measure preoperative plasma fragment D-dimer levels in patients admitted to a gynecologic oncology service. Eight percent of 71 patients with gynecologic cancer had elevated fragment D-dimer levels; none of these patients developed postoperative deep venous thrombosis. Preoperative elevation of the fragment D-dimer level was not predictive of postoperative deep venous thrombosis.

ENT abnormalities associated with Fraser syndrome: case report and literature review

Fraser syndrome is an uncommon genetic disorder characterized by multiple congenital abnormalities. Newborns afflicted with this syndrome have abnormalities of the eyes, ears, nose, larynx, palate, extremities and urogenital system. A review of the literature shows a deficiency in the description of the ENT abnormalities. Most articles have appeared in the ophthalmologic literature with emphasis on the obvious ocular abnormalities. In this paper we will describe in detail, the ear, nose and throat abnormalities in a two-year-old child with Fraser syndrome.

Parathyroid hormone secretion: effect of estradiol and progesterone

Previous studies have shown that estrogen therapy in postmenopausal women results in an increase in serum immunoreactive parathyroid hormone (iPTH) levels. It has been assumed that this effect of estrogen on PTH secretion is indirect, being mediated via mild hypocalcemia resulting from an inhibition of bone resorption. We evaluated the direct effect of 17 beta-estradiol (E2) and of progesterone (Prog) on secretion of PTH from bovine parathyroid tissue in vitro. Both E2 and Prog caused a significant stimulation of PTH secretion within one hour, which was progressive for the three-hour observation period. The responses were dose-related from 10(-7) to 5 X 10(-10) mol/L. There was no PTH response to 10(-7) mol/L alpha-E2, 3-methoxy estriol, estrone, testosterone, or 20-alpha-hydroxy progesterone, indicating specificity of the responses to E2 and Prog. There was a minimal PTH secretory response to 10(-6) mol/L cortisol and 10(-6) mol/L estrone. The E2 receptor antagonist tamoxifen did not inhibit the E2 effect on PTH secretion. This observation plus the rapid PTH response suggests that this hormonal effect may not be via the conventional intracellular E2 receptor. Therefore, E2 and Prog can stimulate PTH secretion by rapid, direct, and specific effects on parathyroid cells. These gonadal hormones may, therefore, be important in calcium homeostasis via their direct stimulatory effect on PTH secretion.